Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * raid5.c : Multiple Devices driver for Linux | |
3 | * Copyright (C) 1996, 1997 Ingo Molnar, Miguel de Icaza, Gadi Oxman | |
4 | * Copyright (C) 1999, 2000 Ingo Molnar | |
16a53ecc | 5 | * Copyright (C) 2002, 2003 H. Peter Anvin |
1da177e4 | 6 | * |
16a53ecc N |
7 | * RAID-4/5/6 management functions. |
8 | * Thanks to Penguin Computing for making the RAID-6 development possible | |
9 | * by donating a test server! | |
1da177e4 LT |
10 | * |
11 | * This program is free software; you can redistribute it and/or modify | |
12 | * it under the terms of the GNU General Public License as published by | |
13 | * the Free Software Foundation; either version 2, or (at your option) | |
14 | * any later version. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License | |
17 | * (for example /usr/src/linux/COPYING); if not, write to the Free | |
18 | * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | |
19 | */ | |
20 | ||
ae3c20cc N |
21 | /* |
22 | * BITMAP UNPLUGGING: | |
23 | * | |
24 | * The sequencing for updating the bitmap reliably is a little | |
25 | * subtle (and I got it wrong the first time) so it deserves some | |
26 | * explanation. | |
27 | * | |
28 | * We group bitmap updates into batches. Each batch has a number. | |
29 | * We may write out several batches at once, but that isn't very important. | |
30 | * conf->bm_write is the number of the last batch successfully written. | |
31 | * conf->bm_flush is the number of the last batch that was closed to | |
32 | * new additions. | |
33 | * When we discover that we will need to write to any block in a stripe | |
34 | * (in add_stripe_bio) we update the in-memory bitmap and record in sh->bm_seq | |
35 | * the number of the batch it will be in. This is bm_flush+1. | |
36 | * When we are ready to do a write, if that batch hasn't been written yet, | |
37 | * we plug the array and queue the stripe for later. | |
38 | * When an unplug happens, we increment bm_flush, thus closing the current | |
39 | * batch. | |
40 | * When we notice that bm_flush > bm_write, we write out all pending updates | |
41 | * to the bitmap, and advance bm_write to where bm_flush was. | |
42 | * This may occasionally write a bit out twice, but is sure never to | |
43 | * miss any bits. | |
44 | */ | |
1da177e4 | 45 | |
bff61975 | 46 | #include <linux/blkdev.h> |
f6705578 | 47 | #include <linux/kthread.h> |
f701d589 | 48 | #include <linux/raid/pq.h> |
91c00924 | 49 | #include <linux/async_tx.h> |
bff61975 | 50 | #include <linux/seq_file.h> |
43b2e5d8 | 51 | #include "md.h" |
bff61975 | 52 | #include "raid5.h" |
ef740c37 | 53 | #include "bitmap.h" |
72626685 | 54 | |
1da177e4 LT |
55 | /* |
56 | * Stripe cache | |
57 | */ | |
58 | ||
59 | #define NR_STRIPES 256 | |
60 | #define STRIPE_SIZE PAGE_SIZE | |
61 | #define STRIPE_SHIFT (PAGE_SHIFT - 9) | |
62 | #define STRIPE_SECTORS (STRIPE_SIZE>>9) | |
63 | #define IO_THRESHOLD 1 | |
8b3e6cdc | 64 | #define BYPASS_THRESHOLD 1 |
fccddba0 | 65 | #define NR_HASH (PAGE_SIZE / sizeof(struct hlist_head)) |
1da177e4 LT |
66 | #define HASH_MASK (NR_HASH - 1) |
67 | ||
fccddba0 | 68 | #define stripe_hash(conf, sect) (&((conf)->stripe_hashtbl[((sect) >> STRIPE_SHIFT) & HASH_MASK])) |
1da177e4 LT |
69 | |
70 | /* bio's attached to a stripe+device for I/O are linked together in bi_sector | |
71 | * order without overlap. There may be several bio's per stripe+device, and | |
72 | * a bio could span several devices. | |
73 | * When walking this list for a particular stripe+device, we must never proceed | |
74 | * beyond a bio that extends past this device, as the next bio might no longer | |
75 | * be valid. | |
76 | * This macro is used to determine the 'next' bio in the list, given the sector | |
77 | * of the current stripe+device | |
78 | */ | |
79 | #define r5_next_bio(bio, sect) ( ( (bio)->bi_sector + ((bio)->bi_size>>9) < sect + STRIPE_SECTORS) ? (bio)->bi_next : NULL) | |
80 | /* | |
81 | * The following can be used to debug the driver | |
82 | */ | |
1da177e4 LT |
83 | #define RAID5_PARANOIA 1 |
84 | #if RAID5_PARANOIA && defined(CONFIG_SMP) | |
85 | # define CHECK_DEVLOCK() assert_spin_locked(&conf->device_lock) | |
86 | #else | |
87 | # define CHECK_DEVLOCK() | |
88 | #endif | |
89 | ||
45b4233c | 90 | #ifdef DEBUG |
1da177e4 LT |
91 | #define inline |
92 | #define __inline__ | |
93 | #endif | |
94 | ||
6be9d494 BS |
95 | #define printk_rl(args...) ((void) (printk_ratelimit() && printk(args))) |
96 | ||
960e739d | 97 | /* |
5b99c2ff JA |
98 | * We maintain a biased count of active stripes in the bottom 16 bits of |
99 | * bi_phys_segments, and a count of processed stripes in the upper 16 bits | |
960e739d JA |
100 | */ |
101 | static inline int raid5_bi_phys_segments(struct bio *bio) | |
102 | { | |
5b99c2ff | 103 | return bio->bi_phys_segments & 0xffff; |
960e739d JA |
104 | } |
105 | ||
106 | static inline int raid5_bi_hw_segments(struct bio *bio) | |
107 | { | |
5b99c2ff | 108 | return (bio->bi_phys_segments >> 16) & 0xffff; |
960e739d JA |
109 | } |
110 | ||
111 | static inline int raid5_dec_bi_phys_segments(struct bio *bio) | |
112 | { | |
113 | --bio->bi_phys_segments; | |
114 | return raid5_bi_phys_segments(bio); | |
115 | } | |
116 | ||
117 | static inline int raid5_dec_bi_hw_segments(struct bio *bio) | |
118 | { | |
119 | unsigned short val = raid5_bi_hw_segments(bio); | |
120 | ||
121 | --val; | |
5b99c2ff | 122 | bio->bi_phys_segments = (val << 16) | raid5_bi_phys_segments(bio); |
960e739d JA |
123 | return val; |
124 | } | |
125 | ||
126 | static inline void raid5_set_bi_hw_segments(struct bio *bio, unsigned int cnt) | |
127 | { | |
5b99c2ff | 128 | bio->bi_phys_segments = raid5_bi_phys_segments(bio) || (cnt << 16); |
960e739d JA |
129 | } |
130 | ||
d0dabf7e N |
131 | /* Find first data disk in a raid6 stripe */ |
132 | static inline int raid6_d0(struct stripe_head *sh) | |
133 | { | |
67cc2b81 N |
134 | if (sh->ddf_layout) |
135 | /* ddf always start from first device */ | |
136 | return 0; | |
137 | /* md starts just after Q block */ | |
d0dabf7e N |
138 | if (sh->qd_idx == sh->disks - 1) |
139 | return 0; | |
140 | else | |
141 | return sh->qd_idx + 1; | |
142 | } | |
16a53ecc N |
143 | static inline int raid6_next_disk(int disk, int raid_disks) |
144 | { | |
145 | disk++; | |
146 | return (disk < raid_disks) ? disk : 0; | |
147 | } | |
a4456856 | 148 | |
d0dabf7e N |
149 | /* When walking through the disks in a raid5, starting at raid6_d0, |
150 | * We need to map each disk to a 'slot', where the data disks are slot | |
151 | * 0 .. raid_disks-3, the parity disk is raid_disks-2 and the Q disk | |
152 | * is raid_disks-1. This help does that mapping. | |
153 | */ | |
67cc2b81 N |
154 | static int raid6_idx_to_slot(int idx, struct stripe_head *sh, |
155 | int *count, int syndrome_disks) | |
d0dabf7e N |
156 | { |
157 | int slot; | |
67cc2b81 | 158 | |
d0dabf7e | 159 | if (idx == sh->pd_idx) |
67cc2b81 | 160 | return syndrome_disks; |
d0dabf7e | 161 | if (idx == sh->qd_idx) |
67cc2b81 | 162 | return syndrome_disks + 1; |
d0dabf7e N |
163 | slot = (*count)++; |
164 | return slot; | |
165 | } | |
166 | ||
a4456856 DW |
167 | static void return_io(struct bio *return_bi) |
168 | { | |
169 | struct bio *bi = return_bi; | |
170 | while (bi) { | |
a4456856 DW |
171 | |
172 | return_bi = bi->bi_next; | |
173 | bi->bi_next = NULL; | |
174 | bi->bi_size = 0; | |
0e13fe23 | 175 | bio_endio(bi, 0); |
a4456856 DW |
176 | bi = return_bi; |
177 | } | |
178 | } | |
179 | ||
1da177e4 LT |
180 | static void print_raid5_conf (raid5_conf_t *conf); |
181 | ||
600aa109 DW |
182 | static int stripe_operations_active(struct stripe_head *sh) |
183 | { | |
184 | return sh->check_state || sh->reconstruct_state || | |
185 | test_bit(STRIPE_BIOFILL_RUN, &sh->state) || | |
186 | test_bit(STRIPE_COMPUTE_RUN, &sh->state); | |
187 | } | |
188 | ||
858119e1 | 189 | static void __release_stripe(raid5_conf_t *conf, struct stripe_head *sh) |
1da177e4 LT |
190 | { |
191 | if (atomic_dec_and_test(&sh->count)) { | |
78bafebd ES |
192 | BUG_ON(!list_empty(&sh->lru)); |
193 | BUG_ON(atomic_read(&conf->active_stripes)==0); | |
1da177e4 | 194 | if (test_bit(STRIPE_HANDLE, &sh->state)) { |
7c785b7a | 195 | if (test_bit(STRIPE_DELAYED, &sh->state)) { |
1da177e4 | 196 | list_add_tail(&sh->lru, &conf->delayed_list); |
7c785b7a N |
197 | blk_plug_device(conf->mddev->queue); |
198 | } else if (test_bit(STRIPE_BIT_DELAY, &sh->state) && | |
ae3c20cc | 199 | sh->bm_seq - conf->seq_write > 0) { |
72626685 | 200 | list_add_tail(&sh->lru, &conf->bitmap_list); |
7c785b7a N |
201 | blk_plug_device(conf->mddev->queue); |
202 | } else { | |
72626685 | 203 | clear_bit(STRIPE_BIT_DELAY, &sh->state); |
1da177e4 | 204 | list_add_tail(&sh->lru, &conf->handle_list); |
72626685 | 205 | } |
1da177e4 LT |
206 | md_wakeup_thread(conf->mddev->thread); |
207 | } else { | |
600aa109 | 208 | BUG_ON(stripe_operations_active(sh)); |
1da177e4 LT |
209 | if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { |
210 | atomic_dec(&conf->preread_active_stripes); | |
211 | if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD) | |
212 | md_wakeup_thread(conf->mddev->thread); | |
213 | } | |
1da177e4 | 214 | atomic_dec(&conf->active_stripes); |
ccfcc3c1 N |
215 | if (!test_bit(STRIPE_EXPANDING, &sh->state)) { |
216 | list_add_tail(&sh->lru, &conf->inactive_list); | |
1da177e4 | 217 | wake_up(&conf->wait_for_stripe); |
46031f9a RBJ |
218 | if (conf->retry_read_aligned) |
219 | md_wakeup_thread(conf->mddev->thread); | |
ccfcc3c1 | 220 | } |
1da177e4 LT |
221 | } |
222 | } | |
223 | } | |
d0dabf7e | 224 | |
1da177e4 LT |
225 | static void release_stripe(struct stripe_head *sh) |
226 | { | |
227 | raid5_conf_t *conf = sh->raid_conf; | |
228 | unsigned long flags; | |
16a53ecc | 229 | |
1da177e4 LT |
230 | spin_lock_irqsave(&conf->device_lock, flags); |
231 | __release_stripe(conf, sh); | |
232 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
233 | } | |
234 | ||
fccddba0 | 235 | static inline void remove_hash(struct stripe_head *sh) |
1da177e4 | 236 | { |
45b4233c DW |
237 | pr_debug("remove_hash(), stripe %llu\n", |
238 | (unsigned long long)sh->sector); | |
1da177e4 | 239 | |
fccddba0 | 240 | hlist_del_init(&sh->hash); |
1da177e4 LT |
241 | } |
242 | ||
16a53ecc | 243 | static inline void insert_hash(raid5_conf_t *conf, struct stripe_head *sh) |
1da177e4 | 244 | { |
fccddba0 | 245 | struct hlist_head *hp = stripe_hash(conf, sh->sector); |
1da177e4 | 246 | |
45b4233c DW |
247 | pr_debug("insert_hash(), stripe %llu\n", |
248 | (unsigned long long)sh->sector); | |
1da177e4 LT |
249 | |
250 | CHECK_DEVLOCK(); | |
fccddba0 | 251 | hlist_add_head(&sh->hash, hp); |
1da177e4 LT |
252 | } |
253 | ||
254 | ||
255 | /* find an idle stripe, make sure it is unhashed, and return it. */ | |
256 | static struct stripe_head *get_free_stripe(raid5_conf_t *conf) | |
257 | { | |
258 | struct stripe_head *sh = NULL; | |
259 | struct list_head *first; | |
260 | ||
261 | CHECK_DEVLOCK(); | |
262 | if (list_empty(&conf->inactive_list)) | |
263 | goto out; | |
264 | first = conf->inactive_list.next; | |
265 | sh = list_entry(first, struct stripe_head, lru); | |
266 | list_del_init(first); | |
267 | remove_hash(sh); | |
268 | atomic_inc(&conf->active_stripes); | |
269 | out: | |
270 | return sh; | |
271 | } | |
272 | ||
273 | static void shrink_buffers(struct stripe_head *sh, int num) | |
274 | { | |
275 | struct page *p; | |
276 | int i; | |
277 | ||
278 | for (i=0; i<num ; i++) { | |
279 | p = sh->dev[i].page; | |
280 | if (!p) | |
281 | continue; | |
282 | sh->dev[i].page = NULL; | |
2d1f3b5d | 283 | put_page(p); |
1da177e4 LT |
284 | } |
285 | } | |
286 | ||
287 | static int grow_buffers(struct stripe_head *sh, int num) | |
288 | { | |
289 | int i; | |
290 | ||
291 | for (i=0; i<num; i++) { | |
292 | struct page *page; | |
293 | ||
294 | if (!(page = alloc_page(GFP_KERNEL))) { | |
295 | return 1; | |
296 | } | |
297 | sh->dev[i].page = page; | |
298 | } | |
299 | return 0; | |
300 | } | |
301 | ||
784052ec | 302 | static void raid5_build_block(struct stripe_head *sh, int i, int previous); |
911d4ee8 N |
303 | static void stripe_set_idx(sector_t stripe, raid5_conf_t *conf, int previous, |
304 | struct stripe_head *sh); | |
1da177e4 | 305 | |
b5663ba4 | 306 | static void init_stripe(struct stripe_head *sh, sector_t sector, int previous) |
1da177e4 LT |
307 | { |
308 | raid5_conf_t *conf = sh->raid_conf; | |
7ecaa1e6 | 309 | int i; |
1da177e4 | 310 | |
78bafebd ES |
311 | BUG_ON(atomic_read(&sh->count) != 0); |
312 | BUG_ON(test_bit(STRIPE_HANDLE, &sh->state)); | |
600aa109 | 313 | BUG_ON(stripe_operations_active(sh)); |
d84e0f10 | 314 | |
1da177e4 | 315 | CHECK_DEVLOCK(); |
45b4233c | 316 | pr_debug("init_stripe called, stripe %llu\n", |
1da177e4 LT |
317 | (unsigned long long)sh->sector); |
318 | ||
319 | remove_hash(sh); | |
16a53ecc | 320 | |
86b42c71 | 321 | sh->generation = conf->generation - previous; |
b5663ba4 | 322 | sh->disks = previous ? conf->previous_raid_disks : conf->raid_disks; |
1da177e4 | 323 | sh->sector = sector; |
911d4ee8 | 324 | stripe_set_idx(sector, conf, previous, sh); |
1da177e4 LT |
325 | sh->state = 0; |
326 | ||
7ecaa1e6 N |
327 | |
328 | for (i = sh->disks; i--; ) { | |
1da177e4 LT |
329 | struct r5dev *dev = &sh->dev[i]; |
330 | ||
d84e0f10 | 331 | if (dev->toread || dev->read || dev->towrite || dev->written || |
1da177e4 | 332 | test_bit(R5_LOCKED, &dev->flags)) { |
d84e0f10 | 333 | printk(KERN_ERR "sector=%llx i=%d %p %p %p %p %d\n", |
1da177e4 | 334 | (unsigned long long)sh->sector, i, dev->toread, |
d84e0f10 | 335 | dev->read, dev->towrite, dev->written, |
1da177e4 LT |
336 | test_bit(R5_LOCKED, &dev->flags)); |
337 | BUG(); | |
338 | } | |
339 | dev->flags = 0; | |
784052ec | 340 | raid5_build_block(sh, i, previous); |
1da177e4 LT |
341 | } |
342 | insert_hash(conf, sh); | |
343 | } | |
344 | ||
86b42c71 N |
345 | static struct stripe_head *__find_stripe(raid5_conf_t *conf, sector_t sector, |
346 | short generation) | |
1da177e4 LT |
347 | { |
348 | struct stripe_head *sh; | |
fccddba0 | 349 | struct hlist_node *hn; |
1da177e4 LT |
350 | |
351 | CHECK_DEVLOCK(); | |
45b4233c | 352 | pr_debug("__find_stripe, sector %llu\n", (unsigned long long)sector); |
fccddba0 | 353 | hlist_for_each_entry(sh, hn, stripe_hash(conf, sector), hash) |
86b42c71 | 354 | if (sh->sector == sector && sh->generation == generation) |
1da177e4 | 355 | return sh; |
45b4233c | 356 | pr_debug("__stripe %llu not in cache\n", (unsigned long long)sector); |
1da177e4 LT |
357 | return NULL; |
358 | } | |
359 | ||
360 | static void unplug_slaves(mddev_t *mddev); | |
165125e1 | 361 | static void raid5_unplug_device(struct request_queue *q); |
1da177e4 | 362 | |
b5663ba4 N |
363 | static struct stripe_head * |
364 | get_active_stripe(raid5_conf_t *conf, sector_t sector, | |
365 | int previous, int noblock) | |
1da177e4 LT |
366 | { |
367 | struct stripe_head *sh; | |
368 | ||
45b4233c | 369 | pr_debug("get_stripe, sector %llu\n", (unsigned long long)sector); |
1da177e4 LT |
370 | |
371 | spin_lock_irq(&conf->device_lock); | |
372 | ||
373 | do { | |
72626685 N |
374 | wait_event_lock_irq(conf->wait_for_stripe, |
375 | conf->quiesce == 0, | |
376 | conf->device_lock, /* nothing */); | |
86b42c71 | 377 | sh = __find_stripe(conf, sector, conf->generation - previous); |
1da177e4 LT |
378 | if (!sh) { |
379 | if (!conf->inactive_blocked) | |
380 | sh = get_free_stripe(conf); | |
381 | if (noblock && sh == NULL) | |
382 | break; | |
383 | if (!sh) { | |
384 | conf->inactive_blocked = 1; | |
385 | wait_event_lock_irq(conf->wait_for_stripe, | |
386 | !list_empty(&conf->inactive_list) && | |
5036805b N |
387 | (atomic_read(&conf->active_stripes) |
388 | < (conf->max_nr_stripes *3/4) | |
1da177e4 LT |
389 | || !conf->inactive_blocked), |
390 | conf->device_lock, | |
f4370781 | 391 | raid5_unplug_device(conf->mddev->queue) |
1da177e4 LT |
392 | ); |
393 | conf->inactive_blocked = 0; | |
394 | } else | |
b5663ba4 | 395 | init_stripe(sh, sector, previous); |
1da177e4 LT |
396 | } else { |
397 | if (atomic_read(&sh->count)) { | |
ab69ae12 N |
398 | BUG_ON(!list_empty(&sh->lru) |
399 | && !test_bit(STRIPE_EXPANDING, &sh->state)); | |
1da177e4 LT |
400 | } else { |
401 | if (!test_bit(STRIPE_HANDLE, &sh->state)) | |
402 | atomic_inc(&conf->active_stripes); | |
ff4e8d9a N |
403 | if (list_empty(&sh->lru) && |
404 | !test_bit(STRIPE_EXPANDING, &sh->state)) | |
16a53ecc N |
405 | BUG(); |
406 | list_del_init(&sh->lru); | |
1da177e4 LT |
407 | } |
408 | } | |
409 | } while (sh == NULL); | |
410 | ||
411 | if (sh) | |
412 | atomic_inc(&sh->count); | |
413 | ||
414 | spin_unlock_irq(&conf->device_lock); | |
415 | return sh; | |
416 | } | |
417 | ||
6712ecf8 N |
418 | static void |
419 | raid5_end_read_request(struct bio *bi, int error); | |
420 | static void | |
421 | raid5_end_write_request(struct bio *bi, int error); | |
91c00924 | 422 | |
c4e5ac0a | 423 | static void ops_run_io(struct stripe_head *sh, struct stripe_head_state *s) |
91c00924 DW |
424 | { |
425 | raid5_conf_t *conf = sh->raid_conf; | |
426 | int i, disks = sh->disks; | |
427 | ||
428 | might_sleep(); | |
429 | ||
430 | for (i = disks; i--; ) { | |
431 | int rw; | |
432 | struct bio *bi; | |
433 | mdk_rdev_t *rdev; | |
434 | if (test_and_clear_bit(R5_Wantwrite, &sh->dev[i].flags)) | |
435 | rw = WRITE; | |
436 | else if (test_and_clear_bit(R5_Wantread, &sh->dev[i].flags)) | |
437 | rw = READ; | |
438 | else | |
439 | continue; | |
440 | ||
441 | bi = &sh->dev[i].req; | |
442 | ||
443 | bi->bi_rw = rw; | |
444 | if (rw == WRITE) | |
445 | bi->bi_end_io = raid5_end_write_request; | |
446 | else | |
447 | bi->bi_end_io = raid5_end_read_request; | |
448 | ||
449 | rcu_read_lock(); | |
450 | rdev = rcu_dereference(conf->disks[i].rdev); | |
451 | if (rdev && test_bit(Faulty, &rdev->flags)) | |
452 | rdev = NULL; | |
453 | if (rdev) | |
454 | atomic_inc(&rdev->nr_pending); | |
455 | rcu_read_unlock(); | |
456 | ||
457 | if (rdev) { | |
c4e5ac0a | 458 | if (s->syncing || s->expanding || s->expanded) |
91c00924 DW |
459 | md_sync_acct(rdev->bdev, STRIPE_SECTORS); |
460 | ||
2b7497f0 DW |
461 | set_bit(STRIPE_IO_STARTED, &sh->state); |
462 | ||
91c00924 DW |
463 | bi->bi_bdev = rdev->bdev; |
464 | pr_debug("%s: for %llu schedule op %ld on disc %d\n", | |
e46b272b | 465 | __func__, (unsigned long long)sh->sector, |
91c00924 DW |
466 | bi->bi_rw, i); |
467 | atomic_inc(&sh->count); | |
468 | bi->bi_sector = sh->sector + rdev->data_offset; | |
469 | bi->bi_flags = 1 << BIO_UPTODATE; | |
470 | bi->bi_vcnt = 1; | |
471 | bi->bi_max_vecs = 1; | |
472 | bi->bi_idx = 0; | |
473 | bi->bi_io_vec = &sh->dev[i].vec; | |
474 | bi->bi_io_vec[0].bv_len = STRIPE_SIZE; | |
475 | bi->bi_io_vec[0].bv_offset = 0; | |
476 | bi->bi_size = STRIPE_SIZE; | |
477 | bi->bi_next = NULL; | |
478 | if (rw == WRITE && | |
479 | test_bit(R5_ReWrite, &sh->dev[i].flags)) | |
480 | atomic_add(STRIPE_SECTORS, | |
481 | &rdev->corrected_errors); | |
482 | generic_make_request(bi); | |
483 | } else { | |
484 | if (rw == WRITE) | |
485 | set_bit(STRIPE_DEGRADED, &sh->state); | |
486 | pr_debug("skip op %ld on disc %d for sector %llu\n", | |
487 | bi->bi_rw, i, (unsigned long long)sh->sector); | |
488 | clear_bit(R5_LOCKED, &sh->dev[i].flags); | |
489 | set_bit(STRIPE_HANDLE, &sh->state); | |
490 | } | |
491 | } | |
492 | } | |
493 | ||
494 | static struct dma_async_tx_descriptor * | |
495 | async_copy_data(int frombio, struct bio *bio, struct page *page, | |
496 | sector_t sector, struct dma_async_tx_descriptor *tx) | |
497 | { | |
498 | struct bio_vec *bvl; | |
499 | struct page *bio_page; | |
500 | int i; | |
501 | int page_offset; | |
502 | ||
503 | if (bio->bi_sector >= sector) | |
504 | page_offset = (signed)(bio->bi_sector - sector) * 512; | |
505 | else | |
506 | page_offset = (signed)(sector - bio->bi_sector) * -512; | |
507 | bio_for_each_segment(bvl, bio, i) { | |
508 | int len = bio_iovec_idx(bio, i)->bv_len; | |
509 | int clen; | |
510 | int b_offset = 0; | |
511 | ||
512 | if (page_offset < 0) { | |
513 | b_offset = -page_offset; | |
514 | page_offset += b_offset; | |
515 | len -= b_offset; | |
516 | } | |
517 | ||
518 | if (len > 0 && page_offset + len > STRIPE_SIZE) | |
519 | clen = STRIPE_SIZE - page_offset; | |
520 | else | |
521 | clen = len; | |
522 | ||
523 | if (clen > 0) { | |
524 | b_offset += bio_iovec_idx(bio, i)->bv_offset; | |
525 | bio_page = bio_iovec_idx(bio, i)->bv_page; | |
526 | if (frombio) | |
527 | tx = async_memcpy(page, bio_page, page_offset, | |
528 | b_offset, clen, | |
eb0645a8 | 529 | ASYNC_TX_DEP_ACK, |
91c00924 DW |
530 | tx, NULL, NULL); |
531 | else | |
532 | tx = async_memcpy(bio_page, page, b_offset, | |
533 | page_offset, clen, | |
eb0645a8 | 534 | ASYNC_TX_DEP_ACK, |
91c00924 DW |
535 | tx, NULL, NULL); |
536 | } | |
537 | if (clen < len) /* hit end of page */ | |
538 | break; | |
539 | page_offset += len; | |
540 | } | |
541 | ||
542 | return tx; | |
543 | } | |
544 | ||
545 | static void ops_complete_biofill(void *stripe_head_ref) | |
546 | { | |
547 | struct stripe_head *sh = stripe_head_ref; | |
548 | struct bio *return_bi = NULL; | |
549 | raid5_conf_t *conf = sh->raid_conf; | |
e4d84909 | 550 | int i; |
91c00924 | 551 | |
e46b272b | 552 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
553 | (unsigned long long)sh->sector); |
554 | ||
555 | /* clear completed biofills */ | |
83de75cc | 556 | spin_lock_irq(&conf->device_lock); |
91c00924 DW |
557 | for (i = sh->disks; i--; ) { |
558 | struct r5dev *dev = &sh->dev[i]; | |
91c00924 DW |
559 | |
560 | /* acknowledge completion of a biofill operation */ | |
e4d84909 DW |
561 | /* and check if we need to reply to a read request, |
562 | * new R5_Wantfill requests are held off until | |
83de75cc | 563 | * !STRIPE_BIOFILL_RUN |
e4d84909 DW |
564 | */ |
565 | if (test_and_clear_bit(R5_Wantfill, &dev->flags)) { | |
91c00924 | 566 | struct bio *rbi, *rbi2; |
91c00924 | 567 | |
91c00924 DW |
568 | BUG_ON(!dev->read); |
569 | rbi = dev->read; | |
570 | dev->read = NULL; | |
571 | while (rbi && rbi->bi_sector < | |
572 | dev->sector + STRIPE_SECTORS) { | |
573 | rbi2 = r5_next_bio(rbi, dev->sector); | |
960e739d | 574 | if (!raid5_dec_bi_phys_segments(rbi)) { |
91c00924 DW |
575 | rbi->bi_next = return_bi; |
576 | return_bi = rbi; | |
577 | } | |
91c00924 DW |
578 | rbi = rbi2; |
579 | } | |
580 | } | |
581 | } | |
83de75cc DW |
582 | spin_unlock_irq(&conf->device_lock); |
583 | clear_bit(STRIPE_BIOFILL_RUN, &sh->state); | |
91c00924 DW |
584 | |
585 | return_io(return_bi); | |
586 | ||
e4d84909 | 587 | set_bit(STRIPE_HANDLE, &sh->state); |
91c00924 DW |
588 | release_stripe(sh); |
589 | } | |
590 | ||
591 | static void ops_run_biofill(struct stripe_head *sh) | |
592 | { | |
593 | struct dma_async_tx_descriptor *tx = NULL; | |
594 | raid5_conf_t *conf = sh->raid_conf; | |
595 | int i; | |
596 | ||
e46b272b | 597 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
598 | (unsigned long long)sh->sector); |
599 | ||
600 | for (i = sh->disks; i--; ) { | |
601 | struct r5dev *dev = &sh->dev[i]; | |
602 | if (test_bit(R5_Wantfill, &dev->flags)) { | |
603 | struct bio *rbi; | |
604 | spin_lock_irq(&conf->device_lock); | |
605 | dev->read = rbi = dev->toread; | |
606 | dev->toread = NULL; | |
607 | spin_unlock_irq(&conf->device_lock); | |
608 | while (rbi && rbi->bi_sector < | |
609 | dev->sector + STRIPE_SECTORS) { | |
610 | tx = async_copy_data(0, rbi, dev->page, | |
611 | dev->sector, tx); | |
612 | rbi = r5_next_bio(rbi, dev->sector); | |
613 | } | |
614 | } | |
615 | } | |
616 | ||
617 | atomic_inc(&sh->count); | |
618 | async_trigger_callback(ASYNC_TX_DEP_ACK | ASYNC_TX_ACK, tx, | |
619 | ops_complete_biofill, sh); | |
620 | } | |
621 | ||
622 | static void ops_complete_compute5(void *stripe_head_ref) | |
623 | { | |
624 | struct stripe_head *sh = stripe_head_ref; | |
625 | int target = sh->ops.target; | |
626 | struct r5dev *tgt = &sh->dev[target]; | |
627 | ||
e46b272b | 628 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
629 | (unsigned long long)sh->sector); |
630 | ||
631 | set_bit(R5_UPTODATE, &tgt->flags); | |
632 | BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags)); | |
633 | clear_bit(R5_Wantcompute, &tgt->flags); | |
ecc65c9b DW |
634 | clear_bit(STRIPE_COMPUTE_RUN, &sh->state); |
635 | if (sh->check_state == check_state_compute_run) | |
636 | sh->check_state = check_state_compute_result; | |
91c00924 DW |
637 | set_bit(STRIPE_HANDLE, &sh->state); |
638 | release_stripe(sh); | |
639 | } | |
640 | ||
7b3a871e | 641 | static struct dma_async_tx_descriptor *ops_run_compute5(struct stripe_head *sh) |
91c00924 DW |
642 | { |
643 | /* kernel stack size limits the total number of disks */ | |
644 | int disks = sh->disks; | |
645 | struct page *xor_srcs[disks]; | |
646 | int target = sh->ops.target; | |
647 | struct r5dev *tgt = &sh->dev[target]; | |
648 | struct page *xor_dest = tgt->page; | |
649 | int count = 0; | |
650 | struct dma_async_tx_descriptor *tx; | |
651 | int i; | |
652 | ||
653 | pr_debug("%s: stripe %llu block: %d\n", | |
e46b272b | 654 | __func__, (unsigned long long)sh->sector, target); |
91c00924 DW |
655 | BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags)); |
656 | ||
657 | for (i = disks; i--; ) | |
658 | if (i != target) | |
659 | xor_srcs[count++] = sh->dev[i].page; | |
660 | ||
661 | atomic_inc(&sh->count); | |
662 | ||
663 | if (unlikely(count == 1)) | |
664 | tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE, | |
665 | 0, NULL, ops_complete_compute5, sh); | |
666 | else | |
667 | tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, | |
668 | ASYNC_TX_XOR_ZERO_DST, NULL, | |
669 | ops_complete_compute5, sh); | |
670 | ||
91c00924 DW |
671 | return tx; |
672 | } | |
673 | ||
674 | static void ops_complete_prexor(void *stripe_head_ref) | |
675 | { | |
676 | struct stripe_head *sh = stripe_head_ref; | |
677 | ||
e46b272b | 678 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 | 679 | (unsigned long long)sh->sector); |
91c00924 DW |
680 | } |
681 | ||
682 | static struct dma_async_tx_descriptor * | |
683 | ops_run_prexor(struct stripe_head *sh, struct dma_async_tx_descriptor *tx) | |
684 | { | |
685 | /* kernel stack size limits the total number of disks */ | |
686 | int disks = sh->disks; | |
687 | struct page *xor_srcs[disks]; | |
688 | int count = 0, pd_idx = sh->pd_idx, i; | |
689 | ||
690 | /* existing parity data subtracted */ | |
691 | struct page *xor_dest = xor_srcs[count++] = sh->dev[pd_idx].page; | |
692 | ||
e46b272b | 693 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
694 | (unsigned long long)sh->sector); |
695 | ||
696 | for (i = disks; i--; ) { | |
697 | struct r5dev *dev = &sh->dev[i]; | |
698 | /* Only process blocks that are known to be uptodate */ | |
d8ee0728 | 699 | if (test_bit(R5_Wantdrain, &dev->flags)) |
91c00924 DW |
700 | xor_srcs[count++] = dev->page; |
701 | } | |
702 | ||
703 | tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, | |
704 | ASYNC_TX_DEP_ACK | ASYNC_TX_XOR_DROP_DST, tx, | |
705 | ops_complete_prexor, sh); | |
706 | ||
707 | return tx; | |
708 | } | |
709 | ||
710 | static struct dma_async_tx_descriptor * | |
d8ee0728 | 711 | ops_run_biodrain(struct stripe_head *sh, struct dma_async_tx_descriptor *tx) |
91c00924 DW |
712 | { |
713 | int disks = sh->disks; | |
d8ee0728 | 714 | int i; |
91c00924 | 715 | |
e46b272b | 716 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
717 | (unsigned long long)sh->sector); |
718 | ||
719 | for (i = disks; i--; ) { | |
720 | struct r5dev *dev = &sh->dev[i]; | |
721 | struct bio *chosen; | |
91c00924 | 722 | |
d8ee0728 | 723 | if (test_and_clear_bit(R5_Wantdrain, &dev->flags)) { |
91c00924 DW |
724 | struct bio *wbi; |
725 | ||
726 | spin_lock(&sh->lock); | |
727 | chosen = dev->towrite; | |
728 | dev->towrite = NULL; | |
729 | BUG_ON(dev->written); | |
730 | wbi = dev->written = chosen; | |
731 | spin_unlock(&sh->lock); | |
732 | ||
733 | while (wbi && wbi->bi_sector < | |
734 | dev->sector + STRIPE_SECTORS) { | |
735 | tx = async_copy_data(1, wbi, dev->page, | |
736 | dev->sector, tx); | |
737 | wbi = r5_next_bio(wbi, dev->sector); | |
738 | } | |
739 | } | |
740 | } | |
741 | ||
742 | return tx; | |
743 | } | |
744 | ||
745 | static void ops_complete_postxor(void *stripe_head_ref) | |
91c00924 DW |
746 | { |
747 | struct stripe_head *sh = stripe_head_ref; | |
748 | int disks = sh->disks, i, pd_idx = sh->pd_idx; | |
749 | ||
e46b272b | 750 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
751 | (unsigned long long)sh->sector); |
752 | ||
753 | for (i = disks; i--; ) { | |
754 | struct r5dev *dev = &sh->dev[i]; | |
755 | if (dev->written || i == pd_idx) | |
756 | set_bit(R5_UPTODATE, &dev->flags); | |
757 | } | |
758 | ||
d8ee0728 DW |
759 | if (sh->reconstruct_state == reconstruct_state_drain_run) |
760 | sh->reconstruct_state = reconstruct_state_drain_result; | |
761 | else if (sh->reconstruct_state == reconstruct_state_prexor_drain_run) | |
762 | sh->reconstruct_state = reconstruct_state_prexor_drain_result; | |
763 | else { | |
764 | BUG_ON(sh->reconstruct_state != reconstruct_state_run); | |
765 | sh->reconstruct_state = reconstruct_state_result; | |
766 | } | |
91c00924 DW |
767 | |
768 | set_bit(STRIPE_HANDLE, &sh->state); | |
769 | release_stripe(sh); | |
770 | } | |
771 | ||
772 | static void | |
d8ee0728 | 773 | ops_run_postxor(struct stripe_head *sh, struct dma_async_tx_descriptor *tx) |
91c00924 DW |
774 | { |
775 | /* kernel stack size limits the total number of disks */ | |
776 | int disks = sh->disks; | |
777 | struct page *xor_srcs[disks]; | |
778 | ||
779 | int count = 0, pd_idx = sh->pd_idx, i; | |
780 | struct page *xor_dest; | |
d8ee0728 | 781 | int prexor = 0; |
91c00924 | 782 | unsigned long flags; |
91c00924 | 783 | |
e46b272b | 784 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
785 | (unsigned long long)sh->sector); |
786 | ||
787 | /* check if prexor is active which means only process blocks | |
788 | * that are part of a read-modify-write (written) | |
789 | */ | |
d8ee0728 DW |
790 | if (sh->reconstruct_state == reconstruct_state_prexor_drain_run) { |
791 | prexor = 1; | |
91c00924 DW |
792 | xor_dest = xor_srcs[count++] = sh->dev[pd_idx].page; |
793 | for (i = disks; i--; ) { | |
794 | struct r5dev *dev = &sh->dev[i]; | |
795 | if (dev->written) | |
796 | xor_srcs[count++] = dev->page; | |
797 | } | |
798 | } else { | |
799 | xor_dest = sh->dev[pd_idx].page; | |
800 | for (i = disks; i--; ) { | |
801 | struct r5dev *dev = &sh->dev[i]; | |
802 | if (i != pd_idx) | |
803 | xor_srcs[count++] = dev->page; | |
804 | } | |
805 | } | |
806 | ||
91c00924 DW |
807 | /* 1/ if we prexor'd then the dest is reused as a source |
808 | * 2/ if we did not prexor then we are redoing the parity | |
809 | * set ASYNC_TX_XOR_DROP_DST and ASYNC_TX_XOR_ZERO_DST | |
810 | * for the synchronous xor case | |
811 | */ | |
812 | flags = ASYNC_TX_DEP_ACK | ASYNC_TX_ACK | | |
813 | (prexor ? ASYNC_TX_XOR_DROP_DST : ASYNC_TX_XOR_ZERO_DST); | |
814 | ||
815 | atomic_inc(&sh->count); | |
816 | ||
817 | if (unlikely(count == 1)) { | |
818 | flags &= ~(ASYNC_TX_XOR_DROP_DST | ASYNC_TX_XOR_ZERO_DST); | |
819 | tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE, | |
d8ee0728 | 820 | flags, tx, ops_complete_postxor, sh); |
91c00924 DW |
821 | } else |
822 | tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, | |
d8ee0728 | 823 | flags, tx, ops_complete_postxor, sh); |
91c00924 DW |
824 | } |
825 | ||
826 | static void ops_complete_check(void *stripe_head_ref) | |
827 | { | |
828 | struct stripe_head *sh = stripe_head_ref; | |
91c00924 | 829 | |
e46b272b | 830 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
831 | (unsigned long long)sh->sector); |
832 | ||
ecc65c9b | 833 | sh->check_state = check_state_check_result; |
91c00924 DW |
834 | set_bit(STRIPE_HANDLE, &sh->state); |
835 | release_stripe(sh); | |
836 | } | |
837 | ||
838 | static void ops_run_check(struct stripe_head *sh) | |
839 | { | |
840 | /* kernel stack size limits the total number of disks */ | |
841 | int disks = sh->disks; | |
842 | struct page *xor_srcs[disks]; | |
843 | struct dma_async_tx_descriptor *tx; | |
844 | ||
845 | int count = 0, pd_idx = sh->pd_idx, i; | |
846 | struct page *xor_dest = xor_srcs[count++] = sh->dev[pd_idx].page; | |
847 | ||
e46b272b | 848 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
849 | (unsigned long long)sh->sector); |
850 | ||
851 | for (i = disks; i--; ) { | |
852 | struct r5dev *dev = &sh->dev[i]; | |
853 | if (i != pd_idx) | |
854 | xor_srcs[count++] = dev->page; | |
855 | } | |
856 | ||
099f53cb | 857 | tx = async_xor_val(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, |
91c00924 DW |
858 | &sh->ops.zero_sum_result, 0, NULL, NULL, NULL); |
859 | ||
91c00924 DW |
860 | atomic_inc(&sh->count); |
861 | tx = async_trigger_callback(ASYNC_TX_DEP_ACK | ASYNC_TX_ACK, tx, | |
862 | ops_complete_check, sh); | |
863 | } | |
864 | ||
600aa109 | 865 | static void raid5_run_ops(struct stripe_head *sh, unsigned long ops_request) |
91c00924 DW |
866 | { |
867 | int overlap_clear = 0, i, disks = sh->disks; | |
868 | struct dma_async_tx_descriptor *tx = NULL; | |
869 | ||
83de75cc | 870 | if (test_bit(STRIPE_OP_BIOFILL, &ops_request)) { |
91c00924 DW |
871 | ops_run_biofill(sh); |
872 | overlap_clear++; | |
873 | } | |
874 | ||
7b3a871e DW |
875 | if (test_bit(STRIPE_OP_COMPUTE_BLK, &ops_request)) { |
876 | tx = ops_run_compute5(sh); | |
877 | /* terminate the chain if postxor is not set to be run */ | |
878 | if (tx && !test_bit(STRIPE_OP_POSTXOR, &ops_request)) | |
879 | async_tx_ack(tx); | |
880 | } | |
91c00924 | 881 | |
600aa109 | 882 | if (test_bit(STRIPE_OP_PREXOR, &ops_request)) |
91c00924 DW |
883 | tx = ops_run_prexor(sh, tx); |
884 | ||
600aa109 | 885 | if (test_bit(STRIPE_OP_BIODRAIN, &ops_request)) { |
d8ee0728 | 886 | tx = ops_run_biodrain(sh, tx); |
91c00924 DW |
887 | overlap_clear++; |
888 | } | |
889 | ||
600aa109 | 890 | if (test_bit(STRIPE_OP_POSTXOR, &ops_request)) |
d8ee0728 | 891 | ops_run_postxor(sh, tx); |
91c00924 | 892 | |
ecc65c9b | 893 | if (test_bit(STRIPE_OP_CHECK, &ops_request)) |
91c00924 DW |
894 | ops_run_check(sh); |
895 | ||
91c00924 DW |
896 | if (overlap_clear) |
897 | for (i = disks; i--; ) { | |
898 | struct r5dev *dev = &sh->dev[i]; | |
899 | if (test_and_clear_bit(R5_Overlap, &dev->flags)) | |
900 | wake_up(&sh->raid_conf->wait_for_overlap); | |
901 | } | |
902 | } | |
903 | ||
3f294f4f | 904 | static int grow_one_stripe(raid5_conf_t *conf) |
1da177e4 LT |
905 | { |
906 | struct stripe_head *sh; | |
3f294f4f N |
907 | sh = kmem_cache_alloc(conf->slab_cache, GFP_KERNEL); |
908 | if (!sh) | |
909 | return 0; | |
910 | memset(sh, 0, sizeof(*sh) + (conf->raid_disks-1)*sizeof(struct r5dev)); | |
911 | sh->raid_conf = conf; | |
912 | spin_lock_init(&sh->lock); | |
913 | ||
914 | if (grow_buffers(sh, conf->raid_disks)) { | |
915 | shrink_buffers(sh, conf->raid_disks); | |
916 | kmem_cache_free(conf->slab_cache, sh); | |
917 | return 0; | |
918 | } | |
7ecaa1e6 | 919 | sh->disks = conf->raid_disks; |
3f294f4f N |
920 | /* we just created an active stripe so... */ |
921 | atomic_set(&sh->count, 1); | |
922 | atomic_inc(&conf->active_stripes); | |
923 | INIT_LIST_HEAD(&sh->lru); | |
924 | release_stripe(sh); | |
925 | return 1; | |
926 | } | |
927 | ||
928 | static int grow_stripes(raid5_conf_t *conf, int num) | |
929 | { | |
e18b890b | 930 | struct kmem_cache *sc; |
1da177e4 LT |
931 | int devs = conf->raid_disks; |
932 | ||
245f46c2 N |
933 | sprintf(conf->cache_name[0], |
934 | "raid%d-%s", conf->level, mdname(conf->mddev)); | |
935 | sprintf(conf->cache_name[1], | |
936 | "raid%d-%s-alt", conf->level, mdname(conf->mddev)); | |
ad01c9e3 N |
937 | conf->active_name = 0; |
938 | sc = kmem_cache_create(conf->cache_name[conf->active_name], | |
1da177e4 | 939 | sizeof(struct stripe_head)+(devs-1)*sizeof(struct r5dev), |
20c2df83 | 940 | 0, 0, NULL); |
1da177e4 LT |
941 | if (!sc) |
942 | return 1; | |
943 | conf->slab_cache = sc; | |
ad01c9e3 | 944 | conf->pool_size = devs; |
16a53ecc | 945 | while (num--) |
3f294f4f | 946 | if (!grow_one_stripe(conf)) |
1da177e4 | 947 | return 1; |
1da177e4 LT |
948 | return 0; |
949 | } | |
29269553 | 950 | |
ad01c9e3 N |
951 | static int resize_stripes(raid5_conf_t *conf, int newsize) |
952 | { | |
953 | /* Make all the stripes able to hold 'newsize' devices. | |
954 | * New slots in each stripe get 'page' set to a new page. | |
955 | * | |
956 | * This happens in stages: | |
957 | * 1/ create a new kmem_cache and allocate the required number of | |
958 | * stripe_heads. | |
959 | * 2/ gather all the old stripe_heads and tranfer the pages across | |
960 | * to the new stripe_heads. This will have the side effect of | |
961 | * freezing the array as once all stripe_heads have been collected, | |
962 | * no IO will be possible. Old stripe heads are freed once their | |
963 | * pages have been transferred over, and the old kmem_cache is | |
964 | * freed when all stripes are done. | |
965 | * 3/ reallocate conf->disks to be suitable bigger. If this fails, | |
966 | * we simple return a failre status - no need to clean anything up. | |
967 | * 4/ allocate new pages for the new slots in the new stripe_heads. | |
968 | * If this fails, we don't bother trying the shrink the | |
969 | * stripe_heads down again, we just leave them as they are. | |
970 | * As each stripe_head is processed the new one is released into | |
971 | * active service. | |
972 | * | |
973 | * Once step2 is started, we cannot afford to wait for a write, | |
974 | * so we use GFP_NOIO allocations. | |
975 | */ | |
976 | struct stripe_head *osh, *nsh; | |
977 | LIST_HEAD(newstripes); | |
978 | struct disk_info *ndisks; | |
b5470dc5 | 979 | int err; |
e18b890b | 980 | struct kmem_cache *sc; |
ad01c9e3 N |
981 | int i; |
982 | ||
983 | if (newsize <= conf->pool_size) | |
984 | return 0; /* never bother to shrink */ | |
985 | ||
b5470dc5 DW |
986 | err = md_allow_write(conf->mddev); |
987 | if (err) | |
988 | return err; | |
2a2275d6 | 989 | |
ad01c9e3 N |
990 | /* Step 1 */ |
991 | sc = kmem_cache_create(conf->cache_name[1-conf->active_name], | |
992 | sizeof(struct stripe_head)+(newsize-1)*sizeof(struct r5dev), | |
20c2df83 | 993 | 0, 0, NULL); |
ad01c9e3 N |
994 | if (!sc) |
995 | return -ENOMEM; | |
996 | ||
997 | for (i = conf->max_nr_stripes; i; i--) { | |
998 | nsh = kmem_cache_alloc(sc, GFP_KERNEL); | |
999 | if (!nsh) | |
1000 | break; | |
1001 | ||
1002 | memset(nsh, 0, sizeof(*nsh) + (newsize-1)*sizeof(struct r5dev)); | |
1003 | ||
1004 | nsh->raid_conf = conf; | |
1005 | spin_lock_init(&nsh->lock); | |
1006 | ||
1007 | list_add(&nsh->lru, &newstripes); | |
1008 | } | |
1009 | if (i) { | |
1010 | /* didn't get enough, give up */ | |
1011 | while (!list_empty(&newstripes)) { | |
1012 | nsh = list_entry(newstripes.next, struct stripe_head, lru); | |
1013 | list_del(&nsh->lru); | |
1014 | kmem_cache_free(sc, nsh); | |
1015 | } | |
1016 | kmem_cache_destroy(sc); | |
1017 | return -ENOMEM; | |
1018 | } | |
1019 | /* Step 2 - Must use GFP_NOIO now. | |
1020 | * OK, we have enough stripes, start collecting inactive | |
1021 | * stripes and copying them over | |
1022 | */ | |
1023 | list_for_each_entry(nsh, &newstripes, lru) { | |
1024 | spin_lock_irq(&conf->device_lock); | |
1025 | wait_event_lock_irq(conf->wait_for_stripe, | |
1026 | !list_empty(&conf->inactive_list), | |
1027 | conf->device_lock, | |
b3b46be3 | 1028 | unplug_slaves(conf->mddev) |
ad01c9e3 N |
1029 | ); |
1030 | osh = get_free_stripe(conf); | |
1031 | spin_unlock_irq(&conf->device_lock); | |
1032 | atomic_set(&nsh->count, 1); | |
1033 | for(i=0; i<conf->pool_size; i++) | |
1034 | nsh->dev[i].page = osh->dev[i].page; | |
1035 | for( ; i<newsize; i++) | |
1036 | nsh->dev[i].page = NULL; | |
1037 | kmem_cache_free(conf->slab_cache, osh); | |
1038 | } | |
1039 | kmem_cache_destroy(conf->slab_cache); | |
1040 | ||
1041 | /* Step 3. | |
1042 | * At this point, we are holding all the stripes so the array | |
1043 | * is completely stalled, so now is a good time to resize | |
1044 | * conf->disks. | |
1045 | */ | |
1046 | ndisks = kzalloc(newsize * sizeof(struct disk_info), GFP_NOIO); | |
1047 | if (ndisks) { | |
1048 | for (i=0; i<conf->raid_disks; i++) | |
1049 | ndisks[i] = conf->disks[i]; | |
1050 | kfree(conf->disks); | |
1051 | conf->disks = ndisks; | |
1052 | } else | |
1053 | err = -ENOMEM; | |
1054 | ||
1055 | /* Step 4, return new stripes to service */ | |
1056 | while(!list_empty(&newstripes)) { | |
1057 | nsh = list_entry(newstripes.next, struct stripe_head, lru); | |
1058 | list_del_init(&nsh->lru); | |
1059 | for (i=conf->raid_disks; i < newsize; i++) | |
1060 | if (nsh->dev[i].page == NULL) { | |
1061 | struct page *p = alloc_page(GFP_NOIO); | |
1062 | nsh->dev[i].page = p; | |
1063 | if (!p) | |
1064 | err = -ENOMEM; | |
1065 | } | |
1066 | release_stripe(nsh); | |
1067 | } | |
1068 | /* critical section pass, GFP_NOIO no longer needed */ | |
1069 | ||
1070 | conf->slab_cache = sc; | |
1071 | conf->active_name = 1-conf->active_name; | |
1072 | conf->pool_size = newsize; | |
1073 | return err; | |
1074 | } | |
1da177e4 | 1075 | |
3f294f4f | 1076 | static int drop_one_stripe(raid5_conf_t *conf) |
1da177e4 LT |
1077 | { |
1078 | struct stripe_head *sh; | |
1079 | ||
3f294f4f N |
1080 | spin_lock_irq(&conf->device_lock); |
1081 | sh = get_free_stripe(conf); | |
1082 | spin_unlock_irq(&conf->device_lock); | |
1083 | if (!sh) | |
1084 | return 0; | |
78bafebd | 1085 | BUG_ON(atomic_read(&sh->count)); |
ad01c9e3 | 1086 | shrink_buffers(sh, conf->pool_size); |
3f294f4f N |
1087 | kmem_cache_free(conf->slab_cache, sh); |
1088 | atomic_dec(&conf->active_stripes); | |
1089 | return 1; | |
1090 | } | |
1091 | ||
1092 | static void shrink_stripes(raid5_conf_t *conf) | |
1093 | { | |
1094 | while (drop_one_stripe(conf)) | |
1095 | ; | |
1096 | ||
29fc7e3e N |
1097 | if (conf->slab_cache) |
1098 | kmem_cache_destroy(conf->slab_cache); | |
1da177e4 LT |
1099 | conf->slab_cache = NULL; |
1100 | } | |
1101 | ||
6712ecf8 | 1102 | static void raid5_end_read_request(struct bio * bi, int error) |
1da177e4 | 1103 | { |
99c0fb5f | 1104 | struct stripe_head *sh = bi->bi_private; |
1da177e4 | 1105 | raid5_conf_t *conf = sh->raid_conf; |
7ecaa1e6 | 1106 | int disks = sh->disks, i; |
1da177e4 | 1107 | int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags); |
d6950432 N |
1108 | char b[BDEVNAME_SIZE]; |
1109 | mdk_rdev_t *rdev; | |
1da177e4 | 1110 | |
1da177e4 LT |
1111 | |
1112 | for (i=0 ; i<disks; i++) | |
1113 | if (bi == &sh->dev[i].req) | |
1114 | break; | |
1115 | ||
45b4233c DW |
1116 | pr_debug("end_read_request %llu/%d, count: %d, uptodate %d.\n", |
1117 | (unsigned long long)sh->sector, i, atomic_read(&sh->count), | |
1da177e4 LT |
1118 | uptodate); |
1119 | if (i == disks) { | |
1120 | BUG(); | |
6712ecf8 | 1121 | return; |
1da177e4 LT |
1122 | } |
1123 | ||
1124 | if (uptodate) { | |
1da177e4 | 1125 | set_bit(R5_UPTODATE, &sh->dev[i].flags); |
4e5314b5 | 1126 | if (test_bit(R5_ReadError, &sh->dev[i].flags)) { |
d6950432 | 1127 | rdev = conf->disks[i].rdev; |
6be9d494 BS |
1128 | printk_rl(KERN_INFO "raid5:%s: read error corrected" |
1129 | " (%lu sectors at %llu on %s)\n", | |
1130 | mdname(conf->mddev), STRIPE_SECTORS, | |
1131 | (unsigned long long)(sh->sector | |
1132 | + rdev->data_offset), | |
1133 | bdevname(rdev->bdev, b)); | |
4e5314b5 N |
1134 | clear_bit(R5_ReadError, &sh->dev[i].flags); |
1135 | clear_bit(R5_ReWrite, &sh->dev[i].flags); | |
1136 | } | |
ba22dcbf N |
1137 | if (atomic_read(&conf->disks[i].rdev->read_errors)) |
1138 | atomic_set(&conf->disks[i].rdev->read_errors, 0); | |
1da177e4 | 1139 | } else { |
d6950432 | 1140 | const char *bdn = bdevname(conf->disks[i].rdev->bdev, b); |
ba22dcbf | 1141 | int retry = 0; |
d6950432 N |
1142 | rdev = conf->disks[i].rdev; |
1143 | ||
1da177e4 | 1144 | clear_bit(R5_UPTODATE, &sh->dev[i].flags); |
d6950432 | 1145 | atomic_inc(&rdev->read_errors); |
ba22dcbf | 1146 | if (conf->mddev->degraded) |
6be9d494 BS |
1147 | printk_rl(KERN_WARNING |
1148 | "raid5:%s: read error not correctable " | |
1149 | "(sector %llu on %s).\n", | |
1150 | mdname(conf->mddev), | |
1151 | (unsigned long long)(sh->sector | |
1152 | + rdev->data_offset), | |
1153 | bdn); | |
ba22dcbf | 1154 | else if (test_bit(R5_ReWrite, &sh->dev[i].flags)) |
4e5314b5 | 1155 | /* Oh, no!!! */ |
6be9d494 BS |
1156 | printk_rl(KERN_WARNING |
1157 | "raid5:%s: read error NOT corrected!! " | |
1158 | "(sector %llu on %s).\n", | |
1159 | mdname(conf->mddev), | |
1160 | (unsigned long long)(sh->sector | |
1161 | + rdev->data_offset), | |
1162 | bdn); | |
d6950432 | 1163 | else if (atomic_read(&rdev->read_errors) |
ba22dcbf | 1164 | > conf->max_nr_stripes) |
14f8d26b | 1165 | printk(KERN_WARNING |
d6950432 N |
1166 | "raid5:%s: Too many read errors, failing device %s.\n", |
1167 | mdname(conf->mddev), bdn); | |
ba22dcbf N |
1168 | else |
1169 | retry = 1; | |
1170 | if (retry) | |
1171 | set_bit(R5_ReadError, &sh->dev[i].flags); | |
1172 | else { | |
4e5314b5 N |
1173 | clear_bit(R5_ReadError, &sh->dev[i].flags); |
1174 | clear_bit(R5_ReWrite, &sh->dev[i].flags); | |
d6950432 | 1175 | md_error(conf->mddev, rdev); |
ba22dcbf | 1176 | } |
1da177e4 LT |
1177 | } |
1178 | rdev_dec_pending(conf->disks[i].rdev, conf->mddev); | |
1da177e4 LT |
1179 | clear_bit(R5_LOCKED, &sh->dev[i].flags); |
1180 | set_bit(STRIPE_HANDLE, &sh->state); | |
1181 | release_stripe(sh); | |
1da177e4 LT |
1182 | } |
1183 | ||
d710e138 | 1184 | static void raid5_end_write_request(struct bio *bi, int error) |
1da177e4 | 1185 | { |
99c0fb5f | 1186 | struct stripe_head *sh = bi->bi_private; |
1da177e4 | 1187 | raid5_conf_t *conf = sh->raid_conf; |
7ecaa1e6 | 1188 | int disks = sh->disks, i; |
1da177e4 LT |
1189 | int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags); |
1190 | ||
1da177e4 LT |
1191 | for (i=0 ; i<disks; i++) |
1192 | if (bi == &sh->dev[i].req) | |
1193 | break; | |
1194 | ||
45b4233c | 1195 | pr_debug("end_write_request %llu/%d, count %d, uptodate: %d.\n", |
1da177e4 LT |
1196 | (unsigned long long)sh->sector, i, atomic_read(&sh->count), |
1197 | uptodate); | |
1198 | if (i == disks) { | |
1199 | BUG(); | |
6712ecf8 | 1200 | return; |
1da177e4 LT |
1201 | } |
1202 | ||
1da177e4 LT |
1203 | if (!uptodate) |
1204 | md_error(conf->mddev, conf->disks[i].rdev); | |
1205 | ||
1206 | rdev_dec_pending(conf->disks[i].rdev, conf->mddev); | |
1207 | ||
1208 | clear_bit(R5_LOCKED, &sh->dev[i].flags); | |
1209 | set_bit(STRIPE_HANDLE, &sh->state); | |
c04be0aa | 1210 | release_stripe(sh); |
1da177e4 LT |
1211 | } |
1212 | ||
1213 | ||
784052ec | 1214 | static sector_t compute_blocknr(struct stripe_head *sh, int i, int previous); |
1da177e4 | 1215 | |
784052ec | 1216 | static void raid5_build_block(struct stripe_head *sh, int i, int previous) |
1da177e4 LT |
1217 | { |
1218 | struct r5dev *dev = &sh->dev[i]; | |
1219 | ||
1220 | bio_init(&dev->req); | |
1221 | dev->req.bi_io_vec = &dev->vec; | |
1222 | dev->req.bi_vcnt++; | |
1223 | dev->req.bi_max_vecs++; | |
1224 | dev->vec.bv_page = dev->page; | |
1225 | dev->vec.bv_len = STRIPE_SIZE; | |
1226 | dev->vec.bv_offset = 0; | |
1227 | ||
1228 | dev->req.bi_sector = sh->sector; | |
1229 | dev->req.bi_private = sh; | |
1230 | ||
1231 | dev->flags = 0; | |
784052ec | 1232 | dev->sector = compute_blocknr(sh, i, previous); |
1da177e4 LT |
1233 | } |
1234 | ||
1235 | static void error(mddev_t *mddev, mdk_rdev_t *rdev) | |
1236 | { | |
1237 | char b[BDEVNAME_SIZE]; | |
1238 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; | |
45b4233c | 1239 | pr_debug("raid5: error called\n"); |
1da177e4 | 1240 | |
b2d444d7 | 1241 | if (!test_bit(Faulty, &rdev->flags)) { |
850b2b42 | 1242 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
c04be0aa N |
1243 | if (test_and_clear_bit(In_sync, &rdev->flags)) { |
1244 | unsigned long flags; | |
1245 | spin_lock_irqsave(&conf->device_lock, flags); | |
1da177e4 | 1246 | mddev->degraded++; |
c04be0aa | 1247 | spin_unlock_irqrestore(&conf->device_lock, flags); |
1da177e4 LT |
1248 | /* |
1249 | * if recovery was running, make sure it aborts. | |
1250 | */ | |
dfc70645 | 1251 | set_bit(MD_RECOVERY_INTR, &mddev->recovery); |
1da177e4 | 1252 | } |
b2d444d7 | 1253 | set_bit(Faulty, &rdev->flags); |
d710e138 N |
1254 | printk(KERN_ALERT |
1255 | "raid5: Disk failure on %s, disabling device.\n" | |
1256 | "raid5: Operation continuing on %d devices.\n", | |
1257 | bdevname(rdev->bdev,b), conf->raid_disks - mddev->degraded); | |
1da177e4 | 1258 | } |
16a53ecc | 1259 | } |
1da177e4 LT |
1260 | |
1261 | /* | |
1262 | * Input: a 'big' sector number, | |
1263 | * Output: index of the data and parity disk, and the sector # in them. | |
1264 | */ | |
112bf897 | 1265 | static sector_t raid5_compute_sector(raid5_conf_t *conf, sector_t r_sector, |
911d4ee8 N |
1266 | int previous, int *dd_idx, |
1267 | struct stripe_head *sh) | |
1da177e4 LT |
1268 | { |
1269 | long stripe; | |
1270 | unsigned long chunk_number; | |
1271 | unsigned int chunk_offset; | |
911d4ee8 | 1272 | int pd_idx, qd_idx; |
67cc2b81 | 1273 | int ddf_layout = 0; |
1da177e4 | 1274 | sector_t new_sector; |
e183eaed N |
1275 | int algorithm = previous ? conf->prev_algo |
1276 | : conf->algorithm; | |
784052ec N |
1277 | int sectors_per_chunk = previous ? (conf->prev_chunk >> 9) |
1278 | : (conf->chunk_size >> 9); | |
112bf897 N |
1279 | int raid_disks = previous ? conf->previous_raid_disks |
1280 | : conf->raid_disks; | |
1281 | int data_disks = raid_disks - conf->max_degraded; | |
1da177e4 LT |
1282 | |
1283 | /* First compute the information on this sector */ | |
1284 | ||
1285 | /* | |
1286 | * Compute the chunk number and the sector offset inside the chunk | |
1287 | */ | |
1288 | chunk_offset = sector_div(r_sector, sectors_per_chunk); | |
1289 | chunk_number = r_sector; | |
1290 | BUG_ON(r_sector != chunk_number); | |
1291 | ||
1292 | /* | |
1293 | * Compute the stripe number | |
1294 | */ | |
1295 | stripe = chunk_number / data_disks; | |
1296 | ||
1297 | /* | |
1298 | * Compute the data disk and parity disk indexes inside the stripe | |
1299 | */ | |
1300 | *dd_idx = chunk_number % data_disks; | |
1301 | ||
1302 | /* | |
1303 | * Select the parity disk based on the user selected algorithm. | |
1304 | */ | |
911d4ee8 | 1305 | pd_idx = qd_idx = ~0; |
16a53ecc N |
1306 | switch(conf->level) { |
1307 | case 4: | |
911d4ee8 | 1308 | pd_idx = data_disks; |
16a53ecc N |
1309 | break; |
1310 | case 5: | |
e183eaed | 1311 | switch (algorithm) { |
1da177e4 | 1312 | case ALGORITHM_LEFT_ASYMMETRIC: |
911d4ee8 N |
1313 | pd_idx = data_disks - stripe % raid_disks; |
1314 | if (*dd_idx >= pd_idx) | |
1da177e4 LT |
1315 | (*dd_idx)++; |
1316 | break; | |
1317 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
911d4ee8 N |
1318 | pd_idx = stripe % raid_disks; |
1319 | if (*dd_idx >= pd_idx) | |
1da177e4 LT |
1320 | (*dd_idx)++; |
1321 | break; | |
1322 | case ALGORITHM_LEFT_SYMMETRIC: | |
911d4ee8 N |
1323 | pd_idx = data_disks - stripe % raid_disks; |
1324 | *dd_idx = (pd_idx + 1 + *dd_idx) % raid_disks; | |
1da177e4 LT |
1325 | break; |
1326 | case ALGORITHM_RIGHT_SYMMETRIC: | |
911d4ee8 N |
1327 | pd_idx = stripe % raid_disks; |
1328 | *dd_idx = (pd_idx + 1 + *dd_idx) % raid_disks; | |
1da177e4 | 1329 | break; |
99c0fb5f N |
1330 | case ALGORITHM_PARITY_0: |
1331 | pd_idx = 0; | |
1332 | (*dd_idx)++; | |
1333 | break; | |
1334 | case ALGORITHM_PARITY_N: | |
1335 | pd_idx = data_disks; | |
1336 | break; | |
1da177e4 | 1337 | default: |
14f8d26b | 1338 | printk(KERN_ERR "raid5: unsupported algorithm %d\n", |
e183eaed | 1339 | algorithm); |
99c0fb5f | 1340 | BUG(); |
16a53ecc N |
1341 | } |
1342 | break; | |
1343 | case 6: | |
1344 | ||
e183eaed | 1345 | switch (algorithm) { |
16a53ecc | 1346 | case ALGORITHM_LEFT_ASYMMETRIC: |
911d4ee8 N |
1347 | pd_idx = raid_disks - 1 - (stripe % raid_disks); |
1348 | qd_idx = pd_idx + 1; | |
1349 | if (pd_idx == raid_disks-1) { | |
99c0fb5f | 1350 | (*dd_idx)++; /* Q D D D P */ |
911d4ee8 N |
1351 | qd_idx = 0; |
1352 | } else if (*dd_idx >= pd_idx) | |
16a53ecc N |
1353 | (*dd_idx) += 2; /* D D P Q D */ |
1354 | break; | |
1355 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
911d4ee8 N |
1356 | pd_idx = stripe % raid_disks; |
1357 | qd_idx = pd_idx + 1; | |
1358 | if (pd_idx == raid_disks-1) { | |
99c0fb5f | 1359 | (*dd_idx)++; /* Q D D D P */ |
911d4ee8 N |
1360 | qd_idx = 0; |
1361 | } else if (*dd_idx >= pd_idx) | |
16a53ecc N |
1362 | (*dd_idx) += 2; /* D D P Q D */ |
1363 | break; | |
1364 | case ALGORITHM_LEFT_SYMMETRIC: | |
911d4ee8 N |
1365 | pd_idx = raid_disks - 1 - (stripe % raid_disks); |
1366 | qd_idx = (pd_idx + 1) % raid_disks; | |
1367 | *dd_idx = (pd_idx + 2 + *dd_idx) % raid_disks; | |
16a53ecc N |
1368 | break; |
1369 | case ALGORITHM_RIGHT_SYMMETRIC: | |
911d4ee8 N |
1370 | pd_idx = stripe % raid_disks; |
1371 | qd_idx = (pd_idx + 1) % raid_disks; | |
1372 | *dd_idx = (pd_idx + 2 + *dd_idx) % raid_disks; | |
16a53ecc | 1373 | break; |
99c0fb5f N |
1374 | |
1375 | case ALGORITHM_PARITY_0: | |
1376 | pd_idx = 0; | |
1377 | qd_idx = 1; | |
1378 | (*dd_idx) += 2; | |
1379 | break; | |
1380 | case ALGORITHM_PARITY_N: | |
1381 | pd_idx = data_disks; | |
1382 | qd_idx = data_disks + 1; | |
1383 | break; | |
1384 | ||
1385 | case ALGORITHM_ROTATING_ZERO_RESTART: | |
1386 | /* Exactly the same as RIGHT_ASYMMETRIC, but or | |
1387 | * of blocks for computing Q is different. | |
1388 | */ | |
1389 | pd_idx = stripe % raid_disks; | |
1390 | qd_idx = pd_idx + 1; | |
1391 | if (pd_idx == raid_disks-1) { | |
1392 | (*dd_idx)++; /* Q D D D P */ | |
1393 | qd_idx = 0; | |
1394 | } else if (*dd_idx >= pd_idx) | |
1395 | (*dd_idx) += 2; /* D D P Q D */ | |
67cc2b81 | 1396 | ddf_layout = 1; |
99c0fb5f N |
1397 | break; |
1398 | ||
1399 | case ALGORITHM_ROTATING_N_RESTART: | |
1400 | /* Same a left_asymmetric, by first stripe is | |
1401 | * D D D P Q rather than | |
1402 | * Q D D D P | |
1403 | */ | |
1404 | pd_idx = raid_disks - 1 - ((stripe + 1) % raid_disks); | |
1405 | qd_idx = pd_idx + 1; | |
1406 | if (pd_idx == raid_disks-1) { | |
1407 | (*dd_idx)++; /* Q D D D P */ | |
1408 | qd_idx = 0; | |
1409 | } else if (*dd_idx >= pd_idx) | |
1410 | (*dd_idx) += 2; /* D D P Q D */ | |
67cc2b81 | 1411 | ddf_layout = 1; |
99c0fb5f N |
1412 | break; |
1413 | ||
1414 | case ALGORITHM_ROTATING_N_CONTINUE: | |
1415 | /* Same as left_symmetric but Q is before P */ | |
1416 | pd_idx = raid_disks - 1 - (stripe % raid_disks); | |
1417 | qd_idx = (pd_idx + raid_disks - 1) % raid_disks; | |
1418 | *dd_idx = (pd_idx + 1 + *dd_idx) % raid_disks; | |
67cc2b81 | 1419 | ddf_layout = 1; |
99c0fb5f N |
1420 | break; |
1421 | ||
1422 | case ALGORITHM_LEFT_ASYMMETRIC_6: | |
1423 | /* RAID5 left_asymmetric, with Q on last device */ | |
1424 | pd_idx = data_disks - stripe % (raid_disks-1); | |
1425 | if (*dd_idx >= pd_idx) | |
1426 | (*dd_idx)++; | |
1427 | qd_idx = raid_disks - 1; | |
1428 | break; | |
1429 | ||
1430 | case ALGORITHM_RIGHT_ASYMMETRIC_6: | |
1431 | pd_idx = stripe % (raid_disks-1); | |
1432 | if (*dd_idx >= pd_idx) | |
1433 | (*dd_idx)++; | |
1434 | qd_idx = raid_disks - 1; | |
1435 | break; | |
1436 | ||
1437 | case ALGORITHM_LEFT_SYMMETRIC_6: | |
1438 | pd_idx = data_disks - stripe % (raid_disks-1); | |
1439 | *dd_idx = (pd_idx + 1 + *dd_idx) % (raid_disks-1); | |
1440 | qd_idx = raid_disks - 1; | |
1441 | break; | |
1442 | ||
1443 | case ALGORITHM_RIGHT_SYMMETRIC_6: | |
1444 | pd_idx = stripe % (raid_disks-1); | |
1445 | *dd_idx = (pd_idx + 1 + *dd_idx) % (raid_disks-1); | |
1446 | qd_idx = raid_disks - 1; | |
1447 | break; | |
1448 | ||
1449 | case ALGORITHM_PARITY_0_6: | |
1450 | pd_idx = 0; | |
1451 | (*dd_idx)++; | |
1452 | qd_idx = raid_disks - 1; | |
1453 | break; | |
1454 | ||
1455 | ||
16a53ecc | 1456 | default: |
d710e138 | 1457 | printk(KERN_CRIT "raid6: unsupported algorithm %d\n", |
e183eaed | 1458 | algorithm); |
99c0fb5f | 1459 | BUG(); |
16a53ecc N |
1460 | } |
1461 | break; | |
1da177e4 LT |
1462 | } |
1463 | ||
911d4ee8 N |
1464 | if (sh) { |
1465 | sh->pd_idx = pd_idx; | |
1466 | sh->qd_idx = qd_idx; | |
67cc2b81 | 1467 | sh->ddf_layout = ddf_layout; |
911d4ee8 | 1468 | } |
1da177e4 LT |
1469 | /* |
1470 | * Finally, compute the new sector number | |
1471 | */ | |
1472 | new_sector = (sector_t)stripe * sectors_per_chunk + chunk_offset; | |
1473 | return new_sector; | |
1474 | } | |
1475 | ||
1476 | ||
784052ec | 1477 | static sector_t compute_blocknr(struct stripe_head *sh, int i, int previous) |
1da177e4 LT |
1478 | { |
1479 | raid5_conf_t *conf = sh->raid_conf; | |
b875e531 N |
1480 | int raid_disks = sh->disks; |
1481 | int data_disks = raid_disks - conf->max_degraded; | |
1da177e4 | 1482 | sector_t new_sector = sh->sector, check; |
784052ec N |
1483 | int sectors_per_chunk = previous ? (conf->prev_chunk >> 9) |
1484 | : (conf->chunk_size >> 9); | |
e183eaed N |
1485 | int algorithm = previous ? conf->prev_algo |
1486 | : conf->algorithm; | |
1da177e4 LT |
1487 | sector_t stripe; |
1488 | int chunk_offset; | |
911d4ee8 | 1489 | int chunk_number, dummy1, dd_idx = i; |
1da177e4 | 1490 | sector_t r_sector; |
911d4ee8 | 1491 | struct stripe_head sh2; |
1da177e4 | 1492 | |
16a53ecc | 1493 | |
1da177e4 LT |
1494 | chunk_offset = sector_div(new_sector, sectors_per_chunk); |
1495 | stripe = new_sector; | |
1496 | BUG_ON(new_sector != stripe); | |
1497 | ||
16a53ecc N |
1498 | if (i == sh->pd_idx) |
1499 | return 0; | |
1500 | switch(conf->level) { | |
1501 | case 4: break; | |
1502 | case 5: | |
e183eaed | 1503 | switch (algorithm) { |
1da177e4 LT |
1504 | case ALGORITHM_LEFT_ASYMMETRIC: |
1505 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
1506 | if (i > sh->pd_idx) | |
1507 | i--; | |
1508 | break; | |
1509 | case ALGORITHM_LEFT_SYMMETRIC: | |
1510 | case ALGORITHM_RIGHT_SYMMETRIC: | |
1511 | if (i < sh->pd_idx) | |
1512 | i += raid_disks; | |
1513 | i -= (sh->pd_idx + 1); | |
1514 | break; | |
99c0fb5f N |
1515 | case ALGORITHM_PARITY_0: |
1516 | i -= 1; | |
1517 | break; | |
1518 | case ALGORITHM_PARITY_N: | |
1519 | break; | |
1da177e4 | 1520 | default: |
14f8d26b | 1521 | printk(KERN_ERR "raid5: unsupported algorithm %d\n", |
e183eaed | 1522 | algorithm); |
99c0fb5f | 1523 | BUG(); |
16a53ecc N |
1524 | } |
1525 | break; | |
1526 | case 6: | |
d0dabf7e | 1527 | if (i == sh->qd_idx) |
16a53ecc | 1528 | return 0; /* It is the Q disk */ |
e183eaed | 1529 | switch (algorithm) { |
16a53ecc N |
1530 | case ALGORITHM_LEFT_ASYMMETRIC: |
1531 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
99c0fb5f N |
1532 | case ALGORITHM_ROTATING_ZERO_RESTART: |
1533 | case ALGORITHM_ROTATING_N_RESTART: | |
1534 | if (sh->pd_idx == raid_disks-1) | |
1535 | i--; /* Q D D D P */ | |
16a53ecc N |
1536 | else if (i > sh->pd_idx) |
1537 | i -= 2; /* D D P Q D */ | |
1538 | break; | |
1539 | case ALGORITHM_LEFT_SYMMETRIC: | |
1540 | case ALGORITHM_RIGHT_SYMMETRIC: | |
1541 | if (sh->pd_idx == raid_disks-1) | |
1542 | i--; /* Q D D D P */ | |
1543 | else { | |
1544 | /* D D P Q D */ | |
1545 | if (i < sh->pd_idx) | |
1546 | i += raid_disks; | |
1547 | i -= (sh->pd_idx + 2); | |
1548 | } | |
1549 | break; | |
99c0fb5f N |
1550 | case ALGORITHM_PARITY_0: |
1551 | i -= 2; | |
1552 | break; | |
1553 | case ALGORITHM_PARITY_N: | |
1554 | break; | |
1555 | case ALGORITHM_ROTATING_N_CONTINUE: | |
1556 | if (sh->pd_idx == 0) | |
1557 | i--; /* P D D D Q */ | |
1558 | else if (i > sh->pd_idx) | |
1559 | i -= 2; /* D D Q P D */ | |
1560 | break; | |
1561 | case ALGORITHM_LEFT_ASYMMETRIC_6: | |
1562 | case ALGORITHM_RIGHT_ASYMMETRIC_6: | |
1563 | if (i > sh->pd_idx) | |
1564 | i--; | |
1565 | break; | |
1566 | case ALGORITHM_LEFT_SYMMETRIC_6: | |
1567 | case ALGORITHM_RIGHT_SYMMETRIC_6: | |
1568 | if (i < sh->pd_idx) | |
1569 | i += data_disks + 1; | |
1570 | i -= (sh->pd_idx + 1); | |
1571 | break; | |
1572 | case ALGORITHM_PARITY_0_6: | |
1573 | i -= 1; | |
1574 | break; | |
16a53ecc | 1575 | default: |
d710e138 | 1576 | printk(KERN_CRIT "raid6: unsupported algorithm %d\n", |
e183eaed | 1577 | algorithm); |
99c0fb5f | 1578 | BUG(); |
16a53ecc N |
1579 | } |
1580 | break; | |
1da177e4 LT |
1581 | } |
1582 | ||
1583 | chunk_number = stripe * data_disks + i; | |
1584 | r_sector = (sector_t)chunk_number * sectors_per_chunk + chunk_offset; | |
1585 | ||
112bf897 | 1586 | check = raid5_compute_sector(conf, r_sector, |
784052ec | 1587 | previous, &dummy1, &sh2); |
911d4ee8 N |
1588 | if (check != sh->sector || dummy1 != dd_idx || sh2.pd_idx != sh->pd_idx |
1589 | || sh2.qd_idx != sh->qd_idx) { | |
14f8d26b | 1590 | printk(KERN_ERR "compute_blocknr: map not correct\n"); |
1da177e4 LT |
1591 | return 0; |
1592 | } | |
1593 | return r_sector; | |
1594 | } | |
1595 | ||
1596 | ||
1597 | ||
1598 | /* | |
16a53ecc N |
1599 | * Copy data between a page in the stripe cache, and one or more bion |
1600 | * The page could align with the middle of the bio, or there could be | |
1601 | * several bion, each with several bio_vecs, which cover part of the page | |
1602 | * Multiple bion are linked together on bi_next. There may be extras | |
1603 | * at the end of this list. We ignore them. | |
1da177e4 LT |
1604 | */ |
1605 | static void copy_data(int frombio, struct bio *bio, | |
1606 | struct page *page, | |
1607 | sector_t sector) | |
1608 | { | |
1609 | char *pa = page_address(page); | |
1610 | struct bio_vec *bvl; | |
1611 | int i; | |
1612 | int page_offset; | |
1613 | ||
1614 | if (bio->bi_sector >= sector) | |
1615 | page_offset = (signed)(bio->bi_sector - sector) * 512; | |
1616 | else | |
1617 | page_offset = (signed)(sector - bio->bi_sector) * -512; | |
1618 | bio_for_each_segment(bvl, bio, i) { | |
1619 | int len = bio_iovec_idx(bio,i)->bv_len; | |
1620 | int clen; | |
1621 | int b_offset = 0; | |
1622 | ||
1623 | if (page_offset < 0) { | |
1624 | b_offset = -page_offset; | |
1625 | page_offset += b_offset; | |
1626 | len -= b_offset; | |
1627 | } | |
1628 | ||
1629 | if (len > 0 && page_offset + len > STRIPE_SIZE) | |
1630 | clen = STRIPE_SIZE - page_offset; | |
1631 | else clen = len; | |
16a53ecc | 1632 | |
1da177e4 LT |
1633 | if (clen > 0) { |
1634 | char *ba = __bio_kmap_atomic(bio, i, KM_USER0); | |
1635 | if (frombio) | |
1636 | memcpy(pa+page_offset, ba+b_offset, clen); | |
1637 | else | |
1638 | memcpy(ba+b_offset, pa+page_offset, clen); | |
1639 | __bio_kunmap_atomic(ba, KM_USER0); | |
1640 | } | |
1641 | if (clen < len) /* hit end of page */ | |
1642 | break; | |
1643 | page_offset += len; | |
1644 | } | |
1645 | } | |
1646 | ||
9bc89cd8 DW |
1647 | #define check_xor() do { \ |
1648 | if (count == MAX_XOR_BLOCKS) { \ | |
1649 | xor_blocks(count, STRIPE_SIZE, dest, ptr);\ | |
1650 | count = 0; \ | |
1651 | } \ | |
1da177e4 LT |
1652 | } while(0) |
1653 | ||
16a53ecc N |
1654 | static void compute_parity6(struct stripe_head *sh, int method) |
1655 | { | |
bff61975 | 1656 | raid5_conf_t *conf = sh->raid_conf; |
d0dabf7e | 1657 | int i, pd_idx, qd_idx, d0_idx, disks = sh->disks, count; |
67cc2b81 | 1658 | int syndrome_disks = sh->ddf_layout ? disks : (disks - 2); |
16a53ecc N |
1659 | struct bio *chosen; |
1660 | /**** FIX THIS: This could be very bad if disks is close to 256 ****/ | |
67cc2b81 | 1661 | void *ptrs[syndrome_disks+2]; |
16a53ecc | 1662 | |
d0dabf7e N |
1663 | pd_idx = sh->pd_idx; |
1664 | qd_idx = sh->qd_idx; | |
1665 | d0_idx = raid6_d0(sh); | |
16a53ecc | 1666 | |
45b4233c | 1667 | pr_debug("compute_parity, stripe %llu, method %d\n", |
16a53ecc N |
1668 | (unsigned long long)sh->sector, method); |
1669 | ||
1670 | switch(method) { | |
1671 | case READ_MODIFY_WRITE: | |
1672 | BUG(); /* READ_MODIFY_WRITE N/A for RAID-6 */ | |
1673 | case RECONSTRUCT_WRITE: | |
1674 | for (i= disks; i-- ;) | |
1675 | if ( i != pd_idx && i != qd_idx && sh->dev[i].towrite ) { | |
1676 | chosen = sh->dev[i].towrite; | |
1677 | sh->dev[i].towrite = NULL; | |
1678 | ||
1679 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) | |
1680 | wake_up(&conf->wait_for_overlap); | |
1681 | ||
52e5f9d1 | 1682 | BUG_ON(sh->dev[i].written); |
16a53ecc N |
1683 | sh->dev[i].written = chosen; |
1684 | } | |
1685 | break; | |
1686 | case CHECK_PARITY: | |
1687 | BUG(); /* Not implemented yet */ | |
1688 | } | |
1689 | ||
1690 | for (i = disks; i--;) | |
1691 | if (sh->dev[i].written) { | |
1692 | sector_t sector = sh->dev[i].sector; | |
1693 | struct bio *wbi = sh->dev[i].written; | |
1694 | while (wbi && wbi->bi_sector < sector + STRIPE_SECTORS) { | |
1695 | copy_data(1, wbi, sh->dev[i].page, sector); | |
1696 | wbi = r5_next_bio(wbi, sector); | |
1697 | } | |
1698 | ||
1699 | set_bit(R5_LOCKED, &sh->dev[i].flags); | |
1700 | set_bit(R5_UPTODATE, &sh->dev[i].flags); | |
1701 | } | |
1702 | ||
d0dabf7e | 1703 | /* Note that unlike RAID-5, the ordering of the disks matters greatly.*/ |
67cc2b81 N |
1704 | |
1705 | for (i = 0; i < disks; i++) | |
1706 | ptrs[i] = (void *)raid6_empty_zero_page; | |
1707 | ||
d0dabf7e N |
1708 | count = 0; |
1709 | i = d0_idx; | |
1710 | do { | |
67cc2b81 N |
1711 | int slot = raid6_idx_to_slot(i, sh, &count, syndrome_disks); |
1712 | ||
d0dabf7e | 1713 | ptrs[slot] = page_address(sh->dev[i].page); |
67cc2b81 | 1714 | if (slot < syndrome_disks && |
d0dabf7e N |
1715 | !test_bit(R5_UPTODATE, &sh->dev[i].flags)) { |
1716 | printk(KERN_ERR "block %d/%d not uptodate " | |
1717 | "on parity calc\n", i, count); | |
1718 | BUG(); | |
1719 | } | |
67cc2b81 | 1720 | |
d0dabf7e N |
1721 | i = raid6_next_disk(i, disks); |
1722 | } while (i != d0_idx); | |
67cc2b81 | 1723 | BUG_ON(count != syndrome_disks); |
16a53ecc | 1724 | |
67cc2b81 | 1725 | raid6_call.gen_syndrome(syndrome_disks+2, STRIPE_SIZE, ptrs); |
16a53ecc N |
1726 | |
1727 | switch(method) { | |
1728 | case RECONSTRUCT_WRITE: | |
1729 | set_bit(R5_UPTODATE, &sh->dev[pd_idx].flags); | |
1730 | set_bit(R5_UPTODATE, &sh->dev[qd_idx].flags); | |
1731 | set_bit(R5_LOCKED, &sh->dev[pd_idx].flags); | |
1732 | set_bit(R5_LOCKED, &sh->dev[qd_idx].flags); | |
1733 | break; | |
1734 | case UPDATE_PARITY: | |
1735 | set_bit(R5_UPTODATE, &sh->dev[pd_idx].flags); | |
1736 | set_bit(R5_UPTODATE, &sh->dev[qd_idx].flags); | |
1737 | break; | |
1738 | } | |
1739 | } | |
1740 | ||
1741 | ||
1742 | /* Compute one missing block */ | |
1743 | static void compute_block_1(struct stripe_head *sh, int dd_idx, int nozero) | |
1744 | { | |
f416885e | 1745 | int i, count, disks = sh->disks; |
9bc89cd8 | 1746 | void *ptr[MAX_XOR_BLOCKS], *dest, *p; |
d0dabf7e | 1747 | int qd_idx = sh->qd_idx; |
16a53ecc | 1748 | |
45b4233c | 1749 | pr_debug("compute_block_1, stripe %llu, idx %d\n", |
16a53ecc N |
1750 | (unsigned long long)sh->sector, dd_idx); |
1751 | ||
1752 | if ( dd_idx == qd_idx ) { | |
1753 | /* We're actually computing the Q drive */ | |
1754 | compute_parity6(sh, UPDATE_PARITY); | |
1755 | } else { | |
9bc89cd8 DW |
1756 | dest = page_address(sh->dev[dd_idx].page); |
1757 | if (!nozero) memset(dest, 0, STRIPE_SIZE); | |
1758 | count = 0; | |
16a53ecc N |
1759 | for (i = disks ; i--; ) { |
1760 | if (i == dd_idx || i == qd_idx) | |
1761 | continue; | |
1762 | p = page_address(sh->dev[i].page); | |
1763 | if (test_bit(R5_UPTODATE, &sh->dev[i].flags)) | |
1764 | ptr[count++] = p; | |
1765 | else | |
1766 | printk("compute_block() %d, stripe %llu, %d" | |
1767 | " not present\n", dd_idx, | |
1768 | (unsigned long long)sh->sector, i); | |
1769 | ||
1770 | check_xor(); | |
1771 | } | |
9bc89cd8 DW |
1772 | if (count) |
1773 | xor_blocks(count, STRIPE_SIZE, dest, ptr); | |
16a53ecc N |
1774 | if (!nozero) set_bit(R5_UPTODATE, &sh->dev[dd_idx].flags); |
1775 | else clear_bit(R5_UPTODATE, &sh->dev[dd_idx].flags); | |
1776 | } | |
1777 | } | |
1778 | ||
1779 | /* Compute two missing blocks */ | |
1780 | static void compute_block_2(struct stripe_head *sh, int dd_idx1, int dd_idx2) | |
1781 | { | |
f416885e | 1782 | int i, count, disks = sh->disks; |
67cc2b81 | 1783 | int syndrome_disks = sh->ddf_layout ? disks : disks-2; |
d0dabf7e N |
1784 | int d0_idx = raid6_d0(sh); |
1785 | int faila = -1, failb = -1; | |
1786 | /**** FIX THIS: This could be very bad if disks is close to 256 ****/ | |
67cc2b81 | 1787 | void *ptrs[syndrome_disks+2]; |
16a53ecc | 1788 | |
67cc2b81 N |
1789 | for (i = 0; i < disks ; i++) |
1790 | ptrs[i] = (void *)raid6_empty_zero_page; | |
d0dabf7e N |
1791 | count = 0; |
1792 | i = d0_idx; | |
1793 | do { | |
67cc2b81 N |
1794 | int slot = raid6_idx_to_slot(i, sh, &count, syndrome_disks); |
1795 | ||
d0dabf7e | 1796 | ptrs[slot] = page_address(sh->dev[i].page); |
67cc2b81 | 1797 | |
d0dabf7e N |
1798 | if (i == dd_idx1) |
1799 | faila = slot; | |
1800 | if (i == dd_idx2) | |
1801 | failb = slot; | |
1802 | i = raid6_next_disk(i, disks); | |
1803 | } while (i != d0_idx); | |
67cc2b81 | 1804 | BUG_ON(count != syndrome_disks); |
16a53ecc N |
1805 | |
1806 | BUG_ON(faila == failb); | |
1807 | if ( failb < faila ) { int tmp = faila; faila = failb; failb = tmp; } | |
1808 | ||
45b4233c | 1809 | pr_debug("compute_block_2, stripe %llu, idx %d,%d (%d,%d)\n", |
d0dabf7e N |
1810 | (unsigned long long)sh->sector, dd_idx1, dd_idx2, |
1811 | faila, failb); | |
16a53ecc | 1812 | |
67cc2b81 | 1813 | if (failb == syndrome_disks+1) { |
16a53ecc | 1814 | /* Q disk is one of the missing disks */ |
67cc2b81 | 1815 | if (faila == syndrome_disks) { |
16a53ecc N |
1816 | /* Missing P+Q, just recompute */ |
1817 | compute_parity6(sh, UPDATE_PARITY); | |
1818 | return; | |
1819 | } else { | |
1820 | /* We're missing D+Q; recompute D from P */ | |
d0dabf7e N |
1821 | compute_block_1(sh, ((dd_idx1 == sh->qd_idx) ? |
1822 | dd_idx2 : dd_idx1), | |
1823 | 0); | |
16a53ecc N |
1824 | compute_parity6(sh, UPDATE_PARITY); /* Is this necessary? */ |
1825 | return; | |
1826 | } | |
1827 | } | |
1828 | ||
d0dabf7e | 1829 | /* We're missing D+P or D+D; */ |
67cc2b81 | 1830 | if (failb == syndrome_disks) { |
d0dabf7e | 1831 | /* We're missing D+P. */ |
67cc2b81 | 1832 | raid6_datap_recov(syndrome_disks+2, STRIPE_SIZE, faila, ptrs); |
d0dabf7e N |
1833 | } else { |
1834 | /* We're missing D+D. */ | |
67cc2b81 N |
1835 | raid6_2data_recov(syndrome_disks+2, STRIPE_SIZE, faila, failb, |
1836 | ptrs); | |
16a53ecc | 1837 | } |
d0dabf7e N |
1838 | |
1839 | /* Both the above update both missing blocks */ | |
1840 | set_bit(R5_UPTODATE, &sh->dev[dd_idx1].flags); | |
1841 | set_bit(R5_UPTODATE, &sh->dev[dd_idx2].flags); | |
16a53ecc N |
1842 | } |
1843 | ||
600aa109 | 1844 | static void |
1fe797e6 | 1845 | schedule_reconstruction5(struct stripe_head *sh, struct stripe_head_state *s, |
600aa109 | 1846 | int rcw, int expand) |
e33129d8 DW |
1847 | { |
1848 | int i, pd_idx = sh->pd_idx, disks = sh->disks; | |
e33129d8 DW |
1849 | |
1850 | if (rcw) { | |
1851 | /* if we are not expanding this is a proper write request, and | |
1852 | * there will be bios with new data to be drained into the | |
1853 | * stripe cache | |
1854 | */ | |
1855 | if (!expand) { | |
600aa109 DW |
1856 | sh->reconstruct_state = reconstruct_state_drain_run; |
1857 | set_bit(STRIPE_OP_BIODRAIN, &s->ops_request); | |
1858 | } else | |
1859 | sh->reconstruct_state = reconstruct_state_run; | |
16a53ecc | 1860 | |
600aa109 | 1861 | set_bit(STRIPE_OP_POSTXOR, &s->ops_request); |
e33129d8 DW |
1862 | |
1863 | for (i = disks; i--; ) { | |
1864 | struct r5dev *dev = &sh->dev[i]; | |
1865 | ||
1866 | if (dev->towrite) { | |
1867 | set_bit(R5_LOCKED, &dev->flags); | |
d8ee0728 | 1868 | set_bit(R5_Wantdrain, &dev->flags); |
e33129d8 DW |
1869 | if (!expand) |
1870 | clear_bit(R5_UPTODATE, &dev->flags); | |
600aa109 | 1871 | s->locked++; |
e33129d8 DW |
1872 | } |
1873 | } | |
600aa109 | 1874 | if (s->locked + 1 == disks) |
8b3e6cdc DW |
1875 | if (!test_and_set_bit(STRIPE_FULL_WRITE, &sh->state)) |
1876 | atomic_inc(&sh->raid_conf->pending_full_writes); | |
e33129d8 DW |
1877 | } else { |
1878 | BUG_ON(!(test_bit(R5_UPTODATE, &sh->dev[pd_idx].flags) || | |
1879 | test_bit(R5_Wantcompute, &sh->dev[pd_idx].flags))); | |
1880 | ||
d8ee0728 | 1881 | sh->reconstruct_state = reconstruct_state_prexor_drain_run; |
600aa109 DW |
1882 | set_bit(STRIPE_OP_PREXOR, &s->ops_request); |
1883 | set_bit(STRIPE_OP_BIODRAIN, &s->ops_request); | |
1884 | set_bit(STRIPE_OP_POSTXOR, &s->ops_request); | |
e33129d8 DW |
1885 | |
1886 | for (i = disks; i--; ) { | |
1887 | struct r5dev *dev = &sh->dev[i]; | |
1888 | if (i == pd_idx) | |
1889 | continue; | |
1890 | ||
e33129d8 DW |
1891 | if (dev->towrite && |
1892 | (test_bit(R5_UPTODATE, &dev->flags) || | |
d8ee0728 DW |
1893 | test_bit(R5_Wantcompute, &dev->flags))) { |
1894 | set_bit(R5_Wantdrain, &dev->flags); | |
e33129d8 DW |
1895 | set_bit(R5_LOCKED, &dev->flags); |
1896 | clear_bit(R5_UPTODATE, &dev->flags); | |
600aa109 | 1897 | s->locked++; |
e33129d8 DW |
1898 | } |
1899 | } | |
1900 | } | |
1901 | ||
1902 | /* keep the parity disk locked while asynchronous operations | |
1903 | * are in flight | |
1904 | */ | |
1905 | set_bit(R5_LOCKED, &sh->dev[pd_idx].flags); | |
1906 | clear_bit(R5_UPTODATE, &sh->dev[pd_idx].flags); | |
600aa109 | 1907 | s->locked++; |
e33129d8 | 1908 | |
600aa109 | 1909 | pr_debug("%s: stripe %llu locked: %d ops_request: %lx\n", |
e46b272b | 1910 | __func__, (unsigned long long)sh->sector, |
600aa109 | 1911 | s->locked, s->ops_request); |
e33129d8 | 1912 | } |
16a53ecc | 1913 | |
1da177e4 LT |
1914 | /* |
1915 | * Each stripe/dev can have one or more bion attached. | |
16a53ecc | 1916 | * toread/towrite point to the first in a chain. |
1da177e4 LT |
1917 | * The bi_next chain must be in order. |
1918 | */ | |
1919 | static int add_stripe_bio(struct stripe_head *sh, struct bio *bi, int dd_idx, int forwrite) | |
1920 | { | |
1921 | struct bio **bip; | |
1922 | raid5_conf_t *conf = sh->raid_conf; | |
72626685 | 1923 | int firstwrite=0; |
1da177e4 | 1924 | |
45b4233c | 1925 | pr_debug("adding bh b#%llu to stripe s#%llu\n", |
1da177e4 LT |
1926 | (unsigned long long)bi->bi_sector, |
1927 | (unsigned long long)sh->sector); | |
1928 | ||
1929 | ||
1930 | spin_lock(&sh->lock); | |
1931 | spin_lock_irq(&conf->device_lock); | |
72626685 | 1932 | if (forwrite) { |
1da177e4 | 1933 | bip = &sh->dev[dd_idx].towrite; |
72626685 N |
1934 | if (*bip == NULL && sh->dev[dd_idx].written == NULL) |
1935 | firstwrite = 1; | |
1936 | } else | |
1da177e4 LT |
1937 | bip = &sh->dev[dd_idx].toread; |
1938 | while (*bip && (*bip)->bi_sector < bi->bi_sector) { | |
1939 | if ((*bip)->bi_sector + ((*bip)->bi_size >> 9) > bi->bi_sector) | |
1940 | goto overlap; | |
1941 | bip = & (*bip)->bi_next; | |
1942 | } | |
1943 | if (*bip && (*bip)->bi_sector < bi->bi_sector + ((bi->bi_size)>>9)) | |
1944 | goto overlap; | |
1945 | ||
78bafebd | 1946 | BUG_ON(*bip && bi->bi_next && (*bip) != bi->bi_next); |
1da177e4 LT |
1947 | if (*bip) |
1948 | bi->bi_next = *bip; | |
1949 | *bip = bi; | |
960e739d | 1950 | bi->bi_phys_segments++; |
1da177e4 LT |
1951 | spin_unlock_irq(&conf->device_lock); |
1952 | spin_unlock(&sh->lock); | |
1953 | ||
45b4233c | 1954 | pr_debug("added bi b#%llu to stripe s#%llu, disk %d.\n", |
1da177e4 LT |
1955 | (unsigned long long)bi->bi_sector, |
1956 | (unsigned long long)sh->sector, dd_idx); | |
1957 | ||
72626685 | 1958 | if (conf->mddev->bitmap && firstwrite) { |
72626685 N |
1959 | bitmap_startwrite(conf->mddev->bitmap, sh->sector, |
1960 | STRIPE_SECTORS, 0); | |
ae3c20cc | 1961 | sh->bm_seq = conf->seq_flush+1; |
72626685 N |
1962 | set_bit(STRIPE_BIT_DELAY, &sh->state); |
1963 | } | |
1964 | ||
1da177e4 LT |
1965 | if (forwrite) { |
1966 | /* check if page is covered */ | |
1967 | sector_t sector = sh->dev[dd_idx].sector; | |
1968 | for (bi=sh->dev[dd_idx].towrite; | |
1969 | sector < sh->dev[dd_idx].sector + STRIPE_SECTORS && | |
1970 | bi && bi->bi_sector <= sector; | |
1971 | bi = r5_next_bio(bi, sh->dev[dd_idx].sector)) { | |
1972 | if (bi->bi_sector + (bi->bi_size>>9) >= sector) | |
1973 | sector = bi->bi_sector + (bi->bi_size>>9); | |
1974 | } | |
1975 | if (sector >= sh->dev[dd_idx].sector + STRIPE_SECTORS) | |
1976 | set_bit(R5_OVERWRITE, &sh->dev[dd_idx].flags); | |
1977 | } | |
1978 | return 1; | |
1979 | ||
1980 | overlap: | |
1981 | set_bit(R5_Overlap, &sh->dev[dd_idx].flags); | |
1982 | spin_unlock_irq(&conf->device_lock); | |
1983 | spin_unlock(&sh->lock); | |
1984 | return 0; | |
1985 | } | |
1986 | ||
29269553 N |
1987 | static void end_reshape(raid5_conf_t *conf); |
1988 | ||
16a53ecc N |
1989 | static int page_is_zero(struct page *p) |
1990 | { | |
1991 | char *a = page_address(p); | |
1992 | return ((*(u32*)a) == 0 && | |
1993 | memcmp(a, a+4, STRIPE_SIZE-4)==0); | |
1994 | } | |
1995 | ||
911d4ee8 N |
1996 | static void stripe_set_idx(sector_t stripe, raid5_conf_t *conf, int previous, |
1997 | struct stripe_head *sh) | |
ccfcc3c1 | 1998 | { |
784052ec N |
1999 | int sectors_per_chunk = |
2000 | previous ? (conf->prev_chunk >> 9) | |
2001 | : (conf->chunk_size >> 9); | |
911d4ee8 | 2002 | int dd_idx; |
2d2063ce | 2003 | int chunk_offset = sector_div(stripe, sectors_per_chunk); |
112bf897 | 2004 | int disks = previous ? conf->previous_raid_disks : conf->raid_disks; |
2d2063ce | 2005 | |
112bf897 N |
2006 | raid5_compute_sector(conf, |
2007 | stripe * (disks - conf->max_degraded) | |
b875e531 | 2008 | *sectors_per_chunk + chunk_offset, |
112bf897 | 2009 | previous, |
911d4ee8 | 2010 | &dd_idx, sh); |
ccfcc3c1 N |
2011 | } |
2012 | ||
a4456856 | 2013 | static void |
1fe797e6 | 2014 | handle_failed_stripe(raid5_conf_t *conf, struct stripe_head *sh, |
a4456856 DW |
2015 | struct stripe_head_state *s, int disks, |
2016 | struct bio **return_bi) | |
2017 | { | |
2018 | int i; | |
2019 | for (i = disks; i--; ) { | |
2020 | struct bio *bi; | |
2021 | int bitmap_end = 0; | |
2022 | ||
2023 | if (test_bit(R5_ReadError, &sh->dev[i].flags)) { | |
2024 | mdk_rdev_t *rdev; | |
2025 | rcu_read_lock(); | |
2026 | rdev = rcu_dereference(conf->disks[i].rdev); | |
2027 | if (rdev && test_bit(In_sync, &rdev->flags)) | |
2028 | /* multiple read failures in one stripe */ | |
2029 | md_error(conf->mddev, rdev); | |
2030 | rcu_read_unlock(); | |
2031 | } | |
2032 | spin_lock_irq(&conf->device_lock); | |
2033 | /* fail all writes first */ | |
2034 | bi = sh->dev[i].towrite; | |
2035 | sh->dev[i].towrite = NULL; | |
2036 | if (bi) { | |
2037 | s->to_write--; | |
2038 | bitmap_end = 1; | |
2039 | } | |
2040 | ||
2041 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) | |
2042 | wake_up(&conf->wait_for_overlap); | |
2043 | ||
2044 | while (bi && bi->bi_sector < | |
2045 | sh->dev[i].sector + STRIPE_SECTORS) { | |
2046 | struct bio *nextbi = r5_next_bio(bi, sh->dev[i].sector); | |
2047 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
960e739d | 2048 | if (!raid5_dec_bi_phys_segments(bi)) { |
a4456856 DW |
2049 | md_write_end(conf->mddev); |
2050 | bi->bi_next = *return_bi; | |
2051 | *return_bi = bi; | |
2052 | } | |
2053 | bi = nextbi; | |
2054 | } | |
2055 | /* and fail all 'written' */ | |
2056 | bi = sh->dev[i].written; | |
2057 | sh->dev[i].written = NULL; | |
2058 | if (bi) bitmap_end = 1; | |
2059 | while (bi && bi->bi_sector < | |
2060 | sh->dev[i].sector + STRIPE_SECTORS) { | |
2061 | struct bio *bi2 = r5_next_bio(bi, sh->dev[i].sector); | |
2062 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
960e739d | 2063 | if (!raid5_dec_bi_phys_segments(bi)) { |
a4456856 DW |
2064 | md_write_end(conf->mddev); |
2065 | bi->bi_next = *return_bi; | |
2066 | *return_bi = bi; | |
2067 | } | |
2068 | bi = bi2; | |
2069 | } | |
2070 | ||
b5e98d65 DW |
2071 | /* fail any reads if this device is non-operational and |
2072 | * the data has not reached the cache yet. | |
2073 | */ | |
2074 | if (!test_bit(R5_Wantfill, &sh->dev[i].flags) && | |
2075 | (!test_bit(R5_Insync, &sh->dev[i].flags) || | |
2076 | test_bit(R5_ReadError, &sh->dev[i].flags))) { | |
a4456856 DW |
2077 | bi = sh->dev[i].toread; |
2078 | sh->dev[i].toread = NULL; | |
2079 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) | |
2080 | wake_up(&conf->wait_for_overlap); | |
2081 | if (bi) s->to_read--; | |
2082 | while (bi && bi->bi_sector < | |
2083 | sh->dev[i].sector + STRIPE_SECTORS) { | |
2084 | struct bio *nextbi = | |
2085 | r5_next_bio(bi, sh->dev[i].sector); | |
2086 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
960e739d | 2087 | if (!raid5_dec_bi_phys_segments(bi)) { |
a4456856 DW |
2088 | bi->bi_next = *return_bi; |
2089 | *return_bi = bi; | |
2090 | } | |
2091 | bi = nextbi; | |
2092 | } | |
2093 | } | |
2094 | spin_unlock_irq(&conf->device_lock); | |
2095 | if (bitmap_end) | |
2096 | bitmap_endwrite(conf->mddev->bitmap, sh->sector, | |
2097 | STRIPE_SECTORS, 0, 0); | |
2098 | } | |
2099 | ||
8b3e6cdc DW |
2100 | if (test_and_clear_bit(STRIPE_FULL_WRITE, &sh->state)) |
2101 | if (atomic_dec_and_test(&conf->pending_full_writes)) | |
2102 | md_wakeup_thread(conf->mddev->thread); | |
a4456856 DW |
2103 | } |
2104 | ||
1fe797e6 DW |
2105 | /* fetch_block5 - checks the given member device to see if its data needs |
2106 | * to be read or computed to satisfy a request. | |
2107 | * | |
2108 | * Returns 1 when no more member devices need to be checked, otherwise returns | |
2109 | * 0 to tell the loop in handle_stripe_fill5 to continue | |
f38e1219 | 2110 | */ |
1fe797e6 DW |
2111 | static int fetch_block5(struct stripe_head *sh, struct stripe_head_state *s, |
2112 | int disk_idx, int disks) | |
f38e1219 DW |
2113 | { |
2114 | struct r5dev *dev = &sh->dev[disk_idx]; | |
2115 | struct r5dev *failed_dev = &sh->dev[s->failed_num]; | |
2116 | ||
f38e1219 DW |
2117 | /* is the data in this block needed, and can we get it? */ |
2118 | if (!test_bit(R5_LOCKED, &dev->flags) && | |
1fe797e6 DW |
2119 | !test_bit(R5_UPTODATE, &dev->flags) && |
2120 | (dev->toread || | |
2121 | (dev->towrite && !test_bit(R5_OVERWRITE, &dev->flags)) || | |
2122 | s->syncing || s->expanding || | |
2123 | (s->failed && | |
2124 | (failed_dev->toread || | |
2125 | (failed_dev->towrite && | |
2126 | !test_bit(R5_OVERWRITE, &failed_dev->flags)))))) { | |
976ea8d4 DW |
2127 | /* We would like to get this block, possibly by computing it, |
2128 | * otherwise read it if the backing disk is insync | |
f38e1219 DW |
2129 | */ |
2130 | if ((s->uptodate == disks - 1) && | |
ecc65c9b | 2131 | (s->failed && disk_idx == s->failed_num)) { |
976ea8d4 DW |
2132 | set_bit(STRIPE_COMPUTE_RUN, &sh->state); |
2133 | set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request); | |
f38e1219 DW |
2134 | set_bit(R5_Wantcompute, &dev->flags); |
2135 | sh->ops.target = disk_idx; | |
2136 | s->req_compute = 1; | |
f38e1219 DW |
2137 | /* Careful: from this point on 'uptodate' is in the eye |
2138 | * of raid5_run_ops which services 'compute' operations | |
2139 | * before writes. R5_Wantcompute flags a block that will | |
2140 | * be R5_UPTODATE by the time it is needed for a | |
2141 | * subsequent operation. | |
2142 | */ | |
2143 | s->uptodate++; | |
1fe797e6 | 2144 | return 1; /* uptodate + compute == disks */ |
7a1fc53c | 2145 | } else if (test_bit(R5_Insync, &dev->flags)) { |
f38e1219 DW |
2146 | set_bit(R5_LOCKED, &dev->flags); |
2147 | set_bit(R5_Wantread, &dev->flags); | |
f38e1219 DW |
2148 | s->locked++; |
2149 | pr_debug("Reading block %d (sync=%d)\n", disk_idx, | |
2150 | s->syncing); | |
2151 | } | |
2152 | } | |
2153 | ||
1fe797e6 | 2154 | return 0; |
f38e1219 DW |
2155 | } |
2156 | ||
1fe797e6 DW |
2157 | /** |
2158 | * handle_stripe_fill5 - read or compute data to satisfy pending requests. | |
2159 | */ | |
2160 | static void handle_stripe_fill5(struct stripe_head *sh, | |
a4456856 DW |
2161 | struct stripe_head_state *s, int disks) |
2162 | { | |
2163 | int i; | |
f38e1219 | 2164 | |
f38e1219 DW |
2165 | /* look for blocks to read/compute, skip this if a compute |
2166 | * is already in flight, or if the stripe contents are in the | |
2167 | * midst of changing due to a write | |
2168 | */ | |
976ea8d4 | 2169 | if (!test_bit(STRIPE_COMPUTE_RUN, &sh->state) && !sh->check_state && |
1fe797e6 | 2170 | !sh->reconstruct_state) |
f38e1219 | 2171 | for (i = disks; i--; ) |
1fe797e6 | 2172 | if (fetch_block5(sh, s, i, disks)) |
f38e1219 | 2173 | break; |
a4456856 DW |
2174 | set_bit(STRIPE_HANDLE, &sh->state); |
2175 | } | |
2176 | ||
1fe797e6 | 2177 | static void handle_stripe_fill6(struct stripe_head *sh, |
a4456856 DW |
2178 | struct stripe_head_state *s, struct r6_state *r6s, |
2179 | int disks) | |
2180 | { | |
2181 | int i; | |
2182 | for (i = disks; i--; ) { | |
2183 | struct r5dev *dev = &sh->dev[i]; | |
2184 | if (!test_bit(R5_LOCKED, &dev->flags) && | |
2185 | !test_bit(R5_UPTODATE, &dev->flags) && | |
2186 | (dev->toread || (dev->towrite && | |
2187 | !test_bit(R5_OVERWRITE, &dev->flags)) || | |
2188 | s->syncing || s->expanding || | |
2189 | (s->failed >= 1 && | |
2190 | (sh->dev[r6s->failed_num[0]].toread || | |
2191 | s->to_write)) || | |
2192 | (s->failed >= 2 && | |
2193 | (sh->dev[r6s->failed_num[1]].toread || | |
2194 | s->to_write)))) { | |
2195 | /* we would like to get this block, possibly | |
2196 | * by computing it, but we might not be able to | |
2197 | */ | |
c337869d DW |
2198 | if ((s->uptodate == disks - 1) && |
2199 | (s->failed && (i == r6s->failed_num[0] || | |
2200 | i == r6s->failed_num[1]))) { | |
45b4233c | 2201 | pr_debug("Computing stripe %llu block %d\n", |
a4456856 DW |
2202 | (unsigned long long)sh->sector, i); |
2203 | compute_block_1(sh, i, 0); | |
2204 | s->uptodate++; | |
2205 | } else if ( s->uptodate == disks-2 && s->failed >= 2 ) { | |
2206 | /* Computing 2-failure is *very* expensive; only | |
2207 | * do it if failed >= 2 | |
2208 | */ | |
2209 | int other; | |
2210 | for (other = disks; other--; ) { | |
2211 | if (other == i) | |
2212 | continue; | |
2213 | if (!test_bit(R5_UPTODATE, | |
2214 | &sh->dev[other].flags)) | |
2215 | break; | |
2216 | } | |
2217 | BUG_ON(other < 0); | |
45b4233c | 2218 | pr_debug("Computing stripe %llu blocks %d,%d\n", |
a4456856 DW |
2219 | (unsigned long long)sh->sector, |
2220 | i, other); | |
2221 | compute_block_2(sh, i, other); | |
2222 | s->uptodate += 2; | |
2223 | } else if (test_bit(R5_Insync, &dev->flags)) { | |
2224 | set_bit(R5_LOCKED, &dev->flags); | |
2225 | set_bit(R5_Wantread, &dev->flags); | |
2226 | s->locked++; | |
45b4233c | 2227 | pr_debug("Reading block %d (sync=%d)\n", |
a4456856 DW |
2228 | i, s->syncing); |
2229 | } | |
2230 | } | |
2231 | } | |
2232 | set_bit(STRIPE_HANDLE, &sh->state); | |
2233 | } | |
2234 | ||
2235 | ||
1fe797e6 | 2236 | /* handle_stripe_clean_event |
a4456856 DW |
2237 | * any written block on an uptodate or failed drive can be returned. |
2238 | * Note that if we 'wrote' to a failed drive, it will be UPTODATE, but | |
2239 | * never LOCKED, so we don't need to test 'failed' directly. | |
2240 | */ | |
1fe797e6 | 2241 | static void handle_stripe_clean_event(raid5_conf_t *conf, |
a4456856 DW |
2242 | struct stripe_head *sh, int disks, struct bio **return_bi) |
2243 | { | |
2244 | int i; | |
2245 | struct r5dev *dev; | |
2246 | ||
2247 | for (i = disks; i--; ) | |
2248 | if (sh->dev[i].written) { | |
2249 | dev = &sh->dev[i]; | |
2250 | if (!test_bit(R5_LOCKED, &dev->flags) && | |
2251 | test_bit(R5_UPTODATE, &dev->flags)) { | |
2252 | /* We can return any write requests */ | |
2253 | struct bio *wbi, *wbi2; | |
2254 | int bitmap_end = 0; | |
45b4233c | 2255 | pr_debug("Return write for disc %d\n", i); |
a4456856 DW |
2256 | spin_lock_irq(&conf->device_lock); |
2257 | wbi = dev->written; | |
2258 | dev->written = NULL; | |
2259 | while (wbi && wbi->bi_sector < | |
2260 | dev->sector + STRIPE_SECTORS) { | |
2261 | wbi2 = r5_next_bio(wbi, dev->sector); | |
960e739d | 2262 | if (!raid5_dec_bi_phys_segments(wbi)) { |
a4456856 DW |
2263 | md_write_end(conf->mddev); |
2264 | wbi->bi_next = *return_bi; | |
2265 | *return_bi = wbi; | |
2266 | } | |
2267 | wbi = wbi2; | |
2268 | } | |
2269 | if (dev->towrite == NULL) | |
2270 | bitmap_end = 1; | |
2271 | spin_unlock_irq(&conf->device_lock); | |
2272 | if (bitmap_end) | |
2273 | bitmap_endwrite(conf->mddev->bitmap, | |
2274 | sh->sector, | |
2275 | STRIPE_SECTORS, | |
2276 | !test_bit(STRIPE_DEGRADED, &sh->state), | |
2277 | 0); | |
2278 | } | |
2279 | } | |
8b3e6cdc DW |
2280 | |
2281 | if (test_and_clear_bit(STRIPE_FULL_WRITE, &sh->state)) | |
2282 | if (atomic_dec_and_test(&conf->pending_full_writes)) | |
2283 | md_wakeup_thread(conf->mddev->thread); | |
a4456856 DW |
2284 | } |
2285 | ||
1fe797e6 | 2286 | static void handle_stripe_dirtying5(raid5_conf_t *conf, |
a4456856 DW |
2287 | struct stripe_head *sh, struct stripe_head_state *s, int disks) |
2288 | { | |
2289 | int rmw = 0, rcw = 0, i; | |
2290 | for (i = disks; i--; ) { | |
2291 | /* would I have to read this buffer for read_modify_write */ | |
2292 | struct r5dev *dev = &sh->dev[i]; | |
2293 | if ((dev->towrite || i == sh->pd_idx) && | |
2294 | !test_bit(R5_LOCKED, &dev->flags) && | |
f38e1219 DW |
2295 | !(test_bit(R5_UPTODATE, &dev->flags) || |
2296 | test_bit(R5_Wantcompute, &dev->flags))) { | |
a4456856 DW |
2297 | if (test_bit(R5_Insync, &dev->flags)) |
2298 | rmw++; | |
2299 | else | |
2300 | rmw += 2*disks; /* cannot read it */ | |
2301 | } | |
2302 | /* Would I have to read this buffer for reconstruct_write */ | |
2303 | if (!test_bit(R5_OVERWRITE, &dev->flags) && i != sh->pd_idx && | |
2304 | !test_bit(R5_LOCKED, &dev->flags) && | |
f38e1219 DW |
2305 | !(test_bit(R5_UPTODATE, &dev->flags) || |
2306 | test_bit(R5_Wantcompute, &dev->flags))) { | |
2307 | if (test_bit(R5_Insync, &dev->flags)) rcw++; | |
a4456856 DW |
2308 | else |
2309 | rcw += 2*disks; | |
2310 | } | |
2311 | } | |
45b4233c | 2312 | pr_debug("for sector %llu, rmw=%d rcw=%d\n", |
a4456856 DW |
2313 | (unsigned long long)sh->sector, rmw, rcw); |
2314 | set_bit(STRIPE_HANDLE, &sh->state); | |
2315 | if (rmw < rcw && rmw > 0) | |
2316 | /* prefer read-modify-write, but need to get some data */ | |
2317 | for (i = disks; i--; ) { | |
2318 | struct r5dev *dev = &sh->dev[i]; | |
2319 | if ((dev->towrite || i == sh->pd_idx) && | |
2320 | !test_bit(R5_LOCKED, &dev->flags) && | |
f38e1219 DW |
2321 | !(test_bit(R5_UPTODATE, &dev->flags) || |
2322 | test_bit(R5_Wantcompute, &dev->flags)) && | |
a4456856 DW |
2323 | test_bit(R5_Insync, &dev->flags)) { |
2324 | if ( | |
2325 | test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
45b4233c | 2326 | pr_debug("Read_old block " |
a4456856 DW |
2327 | "%d for r-m-w\n", i); |
2328 | set_bit(R5_LOCKED, &dev->flags); | |
2329 | set_bit(R5_Wantread, &dev->flags); | |
2330 | s->locked++; | |
2331 | } else { | |
2332 | set_bit(STRIPE_DELAYED, &sh->state); | |
2333 | set_bit(STRIPE_HANDLE, &sh->state); | |
2334 | } | |
2335 | } | |
2336 | } | |
2337 | if (rcw <= rmw && rcw > 0) | |
2338 | /* want reconstruct write, but need to get some data */ | |
2339 | for (i = disks; i--; ) { | |
2340 | struct r5dev *dev = &sh->dev[i]; | |
2341 | if (!test_bit(R5_OVERWRITE, &dev->flags) && | |
2342 | i != sh->pd_idx && | |
2343 | !test_bit(R5_LOCKED, &dev->flags) && | |
f38e1219 DW |
2344 | !(test_bit(R5_UPTODATE, &dev->flags) || |
2345 | test_bit(R5_Wantcompute, &dev->flags)) && | |
a4456856 DW |
2346 | test_bit(R5_Insync, &dev->flags)) { |
2347 | if ( | |
2348 | test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
45b4233c | 2349 | pr_debug("Read_old block " |
a4456856 DW |
2350 | "%d for Reconstruct\n", i); |
2351 | set_bit(R5_LOCKED, &dev->flags); | |
2352 | set_bit(R5_Wantread, &dev->flags); | |
2353 | s->locked++; | |
2354 | } else { | |
2355 | set_bit(STRIPE_DELAYED, &sh->state); | |
2356 | set_bit(STRIPE_HANDLE, &sh->state); | |
2357 | } | |
2358 | } | |
2359 | } | |
2360 | /* now if nothing is locked, and if we have enough data, | |
2361 | * we can start a write request | |
2362 | */ | |
f38e1219 DW |
2363 | /* since handle_stripe can be called at any time we need to handle the |
2364 | * case where a compute block operation has been submitted and then a | |
2365 | * subsequent call wants to start a write request. raid5_run_ops only | |
2366 | * handles the case where compute block and postxor are requested | |
2367 | * simultaneously. If this is not the case then new writes need to be | |
2368 | * held off until the compute completes. | |
2369 | */ | |
976ea8d4 DW |
2370 | if ((s->req_compute || !test_bit(STRIPE_COMPUTE_RUN, &sh->state)) && |
2371 | (s->locked == 0 && (rcw == 0 || rmw == 0) && | |
2372 | !test_bit(STRIPE_BIT_DELAY, &sh->state))) | |
1fe797e6 | 2373 | schedule_reconstruction5(sh, s, rcw == 0, 0); |
a4456856 DW |
2374 | } |
2375 | ||
1fe797e6 | 2376 | static void handle_stripe_dirtying6(raid5_conf_t *conf, |
a4456856 DW |
2377 | struct stripe_head *sh, struct stripe_head_state *s, |
2378 | struct r6_state *r6s, int disks) | |
2379 | { | |
2380 | int rcw = 0, must_compute = 0, pd_idx = sh->pd_idx, i; | |
34e04e87 | 2381 | int qd_idx = sh->qd_idx; |
a4456856 DW |
2382 | for (i = disks; i--; ) { |
2383 | struct r5dev *dev = &sh->dev[i]; | |
2384 | /* Would I have to read this buffer for reconstruct_write */ | |
2385 | if (!test_bit(R5_OVERWRITE, &dev->flags) | |
2386 | && i != pd_idx && i != qd_idx | |
2387 | && (!test_bit(R5_LOCKED, &dev->flags) | |
2388 | ) && | |
2389 | !test_bit(R5_UPTODATE, &dev->flags)) { | |
2390 | if (test_bit(R5_Insync, &dev->flags)) rcw++; | |
2391 | else { | |
45b4233c | 2392 | pr_debug("raid6: must_compute: " |
a4456856 DW |
2393 | "disk %d flags=%#lx\n", i, dev->flags); |
2394 | must_compute++; | |
2395 | } | |
2396 | } | |
2397 | } | |
45b4233c | 2398 | pr_debug("for sector %llu, rcw=%d, must_compute=%d\n", |
a4456856 DW |
2399 | (unsigned long long)sh->sector, rcw, must_compute); |
2400 | set_bit(STRIPE_HANDLE, &sh->state); | |
2401 | ||
2402 | if (rcw > 0) | |
2403 | /* want reconstruct write, but need to get some data */ | |
2404 | for (i = disks; i--; ) { | |
2405 | struct r5dev *dev = &sh->dev[i]; | |
2406 | if (!test_bit(R5_OVERWRITE, &dev->flags) | |
2407 | && !(s->failed == 0 && (i == pd_idx || i == qd_idx)) | |
2408 | && !test_bit(R5_LOCKED, &dev->flags) && | |
2409 | !test_bit(R5_UPTODATE, &dev->flags) && | |
2410 | test_bit(R5_Insync, &dev->flags)) { | |
2411 | if ( | |
2412 | test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
45b4233c | 2413 | pr_debug("Read_old stripe %llu " |
a4456856 DW |
2414 | "block %d for Reconstruct\n", |
2415 | (unsigned long long)sh->sector, i); | |
2416 | set_bit(R5_LOCKED, &dev->flags); | |
2417 | set_bit(R5_Wantread, &dev->flags); | |
2418 | s->locked++; | |
2419 | } else { | |
45b4233c | 2420 | pr_debug("Request delayed stripe %llu " |
a4456856 DW |
2421 | "block %d for Reconstruct\n", |
2422 | (unsigned long long)sh->sector, i); | |
2423 | set_bit(STRIPE_DELAYED, &sh->state); | |
2424 | set_bit(STRIPE_HANDLE, &sh->state); | |
2425 | } | |
2426 | } | |
2427 | } | |
2428 | /* now if nothing is locked, and if we have enough data, we can start a | |
2429 | * write request | |
2430 | */ | |
2431 | if (s->locked == 0 && rcw == 0 && | |
2432 | !test_bit(STRIPE_BIT_DELAY, &sh->state)) { | |
2433 | if (must_compute > 0) { | |
2434 | /* We have failed blocks and need to compute them */ | |
2435 | switch (s->failed) { | |
2436 | case 0: | |
2437 | BUG(); | |
2438 | case 1: | |
2439 | compute_block_1(sh, r6s->failed_num[0], 0); | |
2440 | break; | |
2441 | case 2: | |
2442 | compute_block_2(sh, r6s->failed_num[0], | |
2443 | r6s->failed_num[1]); | |
2444 | break; | |
2445 | default: /* This request should have been failed? */ | |
2446 | BUG(); | |
2447 | } | |
2448 | } | |
2449 | ||
45b4233c | 2450 | pr_debug("Computing parity for stripe %llu\n", |
a4456856 DW |
2451 | (unsigned long long)sh->sector); |
2452 | compute_parity6(sh, RECONSTRUCT_WRITE); | |
2453 | /* now every locked buffer is ready to be written */ | |
2454 | for (i = disks; i--; ) | |
2455 | if (test_bit(R5_LOCKED, &sh->dev[i].flags)) { | |
45b4233c | 2456 | pr_debug("Writing stripe %llu block %d\n", |
a4456856 DW |
2457 | (unsigned long long)sh->sector, i); |
2458 | s->locked++; | |
2459 | set_bit(R5_Wantwrite, &sh->dev[i].flags); | |
2460 | } | |
8b3e6cdc DW |
2461 | if (s->locked == disks) |
2462 | if (!test_and_set_bit(STRIPE_FULL_WRITE, &sh->state)) | |
2463 | atomic_inc(&conf->pending_full_writes); | |
a4456856 DW |
2464 | /* after a RECONSTRUCT_WRITE, the stripe MUST be in-sync */ |
2465 | set_bit(STRIPE_INSYNC, &sh->state); | |
2466 | ||
2467 | if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
2468 | atomic_dec(&conf->preread_active_stripes); | |
2469 | if (atomic_read(&conf->preread_active_stripes) < | |
2470 | IO_THRESHOLD) | |
2471 | md_wakeup_thread(conf->mddev->thread); | |
2472 | } | |
2473 | } | |
2474 | } | |
2475 | ||
2476 | static void handle_parity_checks5(raid5_conf_t *conf, struct stripe_head *sh, | |
2477 | struct stripe_head_state *s, int disks) | |
2478 | { | |
ecc65c9b | 2479 | struct r5dev *dev = NULL; |
bd2ab670 | 2480 | |
a4456856 | 2481 | set_bit(STRIPE_HANDLE, &sh->state); |
e89f8962 | 2482 | |
ecc65c9b DW |
2483 | switch (sh->check_state) { |
2484 | case check_state_idle: | |
2485 | /* start a new check operation if there are no failures */ | |
bd2ab670 | 2486 | if (s->failed == 0) { |
bd2ab670 | 2487 | BUG_ON(s->uptodate != disks); |
ecc65c9b DW |
2488 | sh->check_state = check_state_run; |
2489 | set_bit(STRIPE_OP_CHECK, &s->ops_request); | |
bd2ab670 | 2490 | clear_bit(R5_UPTODATE, &sh->dev[sh->pd_idx].flags); |
bd2ab670 | 2491 | s->uptodate--; |
ecc65c9b | 2492 | break; |
bd2ab670 | 2493 | } |
ecc65c9b DW |
2494 | dev = &sh->dev[s->failed_num]; |
2495 | /* fall through */ | |
2496 | case check_state_compute_result: | |
2497 | sh->check_state = check_state_idle; | |
2498 | if (!dev) | |
2499 | dev = &sh->dev[sh->pd_idx]; | |
2500 | ||
2501 | /* check that a write has not made the stripe insync */ | |
2502 | if (test_bit(STRIPE_INSYNC, &sh->state)) | |
2503 | break; | |
c8894419 | 2504 | |
a4456856 | 2505 | /* either failed parity check, or recovery is happening */ |
a4456856 DW |
2506 | BUG_ON(!test_bit(R5_UPTODATE, &dev->flags)); |
2507 | BUG_ON(s->uptodate != disks); | |
2508 | ||
2509 | set_bit(R5_LOCKED, &dev->flags); | |
ecc65c9b | 2510 | s->locked++; |
a4456856 | 2511 | set_bit(R5_Wantwrite, &dev->flags); |
830ea016 | 2512 | |
a4456856 | 2513 | clear_bit(STRIPE_DEGRADED, &sh->state); |
a4456856 | 2514 | set_bit(STRIPE_INSYNC, &sh->state); |
ecc65c9b DW |
2515 | break; |
2516 | case check_state_run: | |
2517 | break; /* we will be called again upon completion */ | |
2518 | case check_state_check_result: | |
2519 | sh->check_state = check_state_idle; | |
2520 | ||
2521 | /* if a failure occurred during the check operation, leave | |
2522 | * STRIPE_INSYNC not set and let the stripe be handled again | |
2523 | */ | |
2524 | if (s->failed) | |
2525 | break; | |
2526 | ||
2527 | /* handle a successful check operation, if parity is correct | |
2528 | * we are done. Otherwise update the mismatch count and repair | |
2529 | * parity if !MD_RECOVERY_CHECK | |
2530 | */ | |
2531 | if (sh->ops.zero_sum_result == 0) | |
2532 | /* parity is correct (on disc, | |
2533 | * not in buffer any more) | |
2534 | */ | |
2535 | set_bit(STRIPE_INSYNC, &sh->state); | |
2536 | else { | |
2537 | conf->mddev->resync_mismatches += STRIPE_SECTORS; | |
2538 | if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery)) | |
2539 | /* don't try to repair!! */ | |
2540 | set_bit(STRIPE_INSYNC, &sh->state); | |
2541 | else { | |
2542 | sh->check_state = check_state_compute_run; | |
976ea8d4 | 2543 | set_bit(STRIPE_COMPUTE_RUN, &sh->state); |
ecc65c9b DW |
2544 | set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request); |
2545 | set_bit(R5_Wantcompute, | |
2546 | &sh->dev[sh->pd_idx].flags); | |
2547 | sh->ops.target = sh->pd_idx; | |
2548 | s->uptodate++; | |
2549 | } | |
2550 | } | |
2551 | break; | |
2552 | case check_state_compute_run: | |
2553 | break; | |
2554 | default: | |
2555 | printk(KERN_ERR "%s: unknown check_state: %d sector: %llu\n", | |
2556 | __func__, sh->check_state, | |
2557 | (unsigned long long) sh->sector); | |
2558 | BUG(); | |
a4456856 DW |
2559 | } |
2560 | } | |
2561 | ||
2562 | ||
2563 | static void handle_parity_checks6(raid5_conf_t *conf, struct stripe_head *sh, | |
2564 | struct stripe_head_state *s, | |
2565 | struct r6_state *r6s, struct page *tmp_page, | |
2566 | int disks) | |
2567 | { | |
2568 | int update_p = 0, update_q = 0; | |
2569 | struct r5dev *dev; | |
2570 | int pd_idx = sh->pd_idx; | |
34e04e87 | 2571 | int qd_idx = sh->qd_idx; |
a4456856 DW |
2572 | |
2573 | set_bit(STRIPE_HANDLE, &sh->state); | |
2574 | ||
2575 | BUG_ON(s->failed > 2); | |
2576 | BUG_ON(s->uptodate < disks); | |
2577 | /* Want to check and possibly repair P and Q. | |
2578 | * However there could be one 'failed' device, in which | |
2579 | * case we can only check one of them, possibly using the | |
2580 | * other to generate missing data | |
2581 | */ | |
2582 | ||
2583 | /* If !tmp_page, we cannot do the calculations, | |
2584 | * but as we have set STRIPE_HANDLE, we will soon be called | |
2585 | * by stripe_handle with a tmp_page - just wait until then. | |
2586 | */ | |
2587 | if (tmp_page) { | |
2588 | if (s->failed == r6s->q_failed) { | |
2589 | /* The only possible failed device holds 'Q', so it | |
2590 | * makes sense to check P (If anything else were failed, | |
2591 | * we would have used P to recreate it). | |
2592 | */ | |
2593 | compute_block_1(sh, pd_idx, 1); | |
2594 | if (!page_is_zero(sh->dev[pd_idx].page)) { | |
2595 | compute_block_1(sh, pd_idx, 0); | |
2596 | update_p = 1; | |
2597 | } | |
2598 | } | |
2599 | if (!r6s->q_failed && s->failed < 2) { | |
2600 | /* q is not failed, and we didn't use it to generate | |
2601 | * anything, so it makes sense to check it | |
2602 | */ | |
2603 | memcpy(page_address(tmp_page), | |
2604 | page_address(sh->dev[qd_idx].page), | |
2605 | STRIPE_SIZE); | |
2606 | compute_parity6(sh, UPDATE_PARITY); | |
2607 | if (memcmp(page_address(tmp_page), | |
2608 | page_address(sh->dev[qd_idx].page), | |
2609 | STRIPE_SIZE) != 0) { | |
2610 | clear_bit(STRIPE_INSYNC, &sh->state); | |
2611 | update_q = 1; | |
2612 | } | |
2613 | } | |
2614 | if (update_p || update_q) { | |
2615 | conf->mddev->resync_mismatches += STRIPE_SECTORS; | |
2616 | if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery)) | |
2617 | /* don't try to repair!! */ | |
2618 | update_p = update_q = 0; | |
2619 | } | |
2620 | ||
2621 | /* now write out any block on a failed drive, | |
2622 | * or P or Q if they need it | |
2623 | */ | |
2624 | ||
2625 | if (s->failed == 2) { | |
2626 | dev = &sh->dev[r6s->failed_num[1]]; | |
2627 | s->locked++; | |
2628 | set_bit(R5_LOCKED, &dev->flags); | |
2629 | set_bit(R5_Wantwrite, &dev->flags); | |
2630 | } | |
2631 | if (s->failed >= 1) { | |
2632 | dev = &sh->dev[r6s->failed_num[0]]; | |
2633 | s->locked++; | |
2634 | set_bit(R5_LOCKED, &dev->flags); | |
2635 | set_bit(R5_Wantwrite, &dev->flags); | |
2636 | } | |
2637 | ||
2638 | if (update_p) { | |
2639 | dev = &sh->dev[pd_idx]; | |
2640 | s->locked++; | |
2641 | set_bit(R5_LOCKED, &dev->flags); | |
2642 | set_bit(R5_Wantwrite, &dev->flags); | |
2643 | } | |
2644 | if (update_q) { | |
2645 | dev = &sh->dev[qd_idx]; | |
2646 | s->locked++; | |
2647 | set_bit(R5_LOCKED, &dev->flags); | |
2648 | set_bit(R5_Wantwrite, &dev->flags); | |
2649 | } | |
2650 | clear_bit(STRIPE_DEGRADED, &sh->state); | |
2651 | ||
2652 | set_bit(STRIPE_INSYNC, &sh->state); | |
2653 | } | |
2654 | } | |
2655 | ||
2656 | static void handle_stripe_expansion(raid5_conf_t *conf, struct stripe_head *sh, | |
2657 | struct r6_state *r6s) | |
2658 | { | |
2659 | int i; | |
2660 | ||
2661 | /* We have read all the blocks in this stripe and now we need to | |
2662 | * copy some of them into a target stripe for expand. | |
2663 | */ | |
f0a50d37 | 2664 | struct dma_async_tx_descriptor *tx = NULL; |
a4456856 DW |
2665 | clear_bit(STRIPE_EXPAND_SOURCE, &sh->state); |
2666 | for (i = 0; i < sh->disks; i++) | |
34e04e87 | 2667 | if (i != sh->pd_idx && i != sh->qd_idx) { |
911d4ee8 | 2668 | int dd_idx, j; |
a4456856 DW |
2669 | struct stripe_head *sh2; |
2670 | ||
784052ec | 2671 | sector_t bn = compute_blocknr(sh, i, 1); |
911d4ee8 N |
2672 | sector_t s = raid5_compute_sector(conf, bn, 0, |
2673 | &dd_idx, NULL); | |
b5663ba4 | 2674 | sh2 = get_active_stripe(conf, s, 0, 1); |
a4456856 DW |
2675 | if (sh2 == NULL) |
2676 | /* so far only the early blocks of this stripe | |
2677 | * have been requested. When later blocks | |
2678 | * get requested, we will try again | |
2679 | */ | |
2680 | continue; | |
2681 | if (!test_bit(STRIPE_EXPANDING, &sh2->state) || | |
2682 | test_bit(R5_Expanded, &sh2->dev[dd_idx].flags)) { | |
2683 | /* must have already done this block */ | |
2684 | release_stripe(sh2); | |
2685 | continue; | |
2686 | } | |
f0a50d37 DW |
2687 | |
2688 | /* place all the copies on one channel */ | |
2689 | tx = async_memcpy(sh2->dev[dd_idx].page, | |
2690 | sh->dev[i].page, 0, 0, STRIPE_SIZE, | |
2691 | ASYNC_TX_DEP_ACK, tx, NULL, NULL); | |
2692 | ||
a4456856 DW |
2693 | set_bit(R5_Expanded, &sh2->dev[dd_idx].flags); |
2694 | set_bit(R5_UPTODATE, &sh2->dev[dd_idx].flags); | |
2695 | for (j = 0; j < conf->raid_disks; j++) | |
2696 | if (j != sh2->pd_idx && | |
d0dabf7e | 2697 | (!r6s || j != sh2->qd_idx) && |
a4456856 DW |
2698 | !test_bit(R5_Expanded, &sh2->dev[j].flags)) |
2699 | break; | |
2700 | if (j == conf->raid_disks) { | |
2701 | set_bit(STRIPE_EXPAND_READY, &sh2->state); | |
2702 | set_bit(STRIPE_HANDLE, &sh2->state); | |
2703 | } | |
2704 | release_stripe(sh2); | |
f0a50d37 | 2705 | |
a4456856 | 2706 | } |
a2e08551 N |
2707 | /* done submitting copies, wait for them to complete */ |
2708 | if (tx) { | |
2709 | async_tx_ack(tx); | |
2710 | dma_wait_for_async_tx(tx); | |
2711 | } | |
a4456856 | 2712 | } |
1da177e4 | 2713 | |
6bfe0b49 | 2714 | |
1da177e4 LT |
2715 | /* |
2716 | * handle_stripe - do things to a stripe. | |
2717 | * | |
2718 | * We lock the stripe and then examine the state of various bits | |
2719 | * to see what needs to be done. | |
2720 | * Possible results: | |
2721 | * return some read request which now have data | |
2722 | * return some write requests which are safely on disc | |
2723 | * schedule a read on some buffers | |
2724 | * schedule a write of some buffers | |
2725 | * return confirmation of parity correctness | |
2726 | * | |
1da177e4 LT |
2727 | * buffers are taken off read_list or write_list, and bh_cache buffers |
2728 | * get BH_Lock set before the stripe lock is released. | |
2729 | * | |
2730 | */ | |
a4456856 | 2731 | |
df10cfbc | 2732 | static bool handle_stripe5(struct stripe_head *sh) |
1da177e4 LT |
2733 | { |
2734 | raid5_conf_t *conf = sh->raid_conf; | |
a4456856 DW |
2735 | int disks = sh->disks, i; |
2736 | struct bio *return_bi = NULL; | |
2737 | struct stripe_head_state s; | |
1da177e4 | 2738 | struct r5dev *dev; |
6bfe0b49 | 2739 | mdk_rdev_t *blocked_rdev = NULL; |
e0a115e5 | 2740 | int prexor; |
1da177e4 | 2741 | |
a4456856 | 2742 | memset(&s, 0, sizeof(s)); |
600aa109 DW |
2743 | pr_debug("handling stripe %llu, state=%#lx cnt=%d, pd_idx=%d check:%d " |
2744 | "reconstruct:%d\n", (unsigned long long)sh->sector, sh->state, | |
2745 | atomic_read(&sh->count), sh->pd_idx, sh->check_state, | |
2746 | sh->reconstruct_state); | |
1da177e4 LT |
2747 | |
2748 | spin_lock(&sh->lock); | |
2749 | clear_bit(STRIPE_HANDLE, &sh->state); | |
2750 | clear_bit(STRIPE_DELAYED, &sh->state); | |
2751 | ||
a4456856 DW |
2752 | s.syncing = test_bit(STRIPE_SYNCING, &sh->state); |
2753 | s.expanding = test_bit(STRIPE_EXPAND_SOURCE, &sh->state); | |
2754 | s.expanded = test_bit(STRIPE_EXPAND_READY, &sh->state); | |
def6ae26 | 2755 | |
83de75cc | 2756 | /* Now to look around and see what can be done */ |
9910f16a | 2757 | rcu_read_lock(); |
1da177e4 LT |
2758 | for (i=disks; i--; ) { |
2759 | mdk_rdev_t *rdev; | |
a4456856 | 2760 | struct r5dev *dev = &sh->dev[i]; |
1da177e4 | 2761 | clear_bit(R5_Insync, &dev->flags); |
1da177e4 | 2762 | |
b5e98d65 DW |
2763 | pr_debug("check %d: state 0x%lx toread %p read %p write %p " |
2764 | "written %p\n", i, dev->flags, dev->toread, dev->read, | |
2765 | dev->towrite, dev->written); | |
2766 | ||
2767 | /* maybe we can request a biofill operation | |
2768 | * | |
2769 | * new wantfill requests are only permitted while | |
83de75cc | 2770 | * ops_complete_biofill is guaranteed to be inactive |
b5e98d65 DW |
2771 | */ |
2772 | if (test_bit(R5_UPTODATE, &dev->flags) && dev->toread && | |
83de75cc | 2773 | !test_bit(STRIPE_BIOFILL_RUN, &sh->state)) |
b5e98d65 | 2774 | set_bit(R5_Wantfill, &dev->flags); |
1da177e4 LT |
2775 | |
2776 | /* now count some things */ | |
a4456856 DW |
2777 | if (test_bit(R5_LOCKED, &dev->flags)) s.locked++; |
2778 | if (test_bit(R5_UPTODATE, &dev->flags)) s.uptodate++; | |
f38e1219 | 2779 | if (test_bit(R5_Wantcompute, &dev->flags)) s.compute++; |
1da177e4 | 2780 | |
b5e98d65 DW |
2781 | if (test_bit(R5_Wantfill, &dev->flags)) |
2782 | s.to_fill++; | |
2783 | else if (dev->toread) | |
a4456856 | 2784 | s.to_read++; |
1da177e4 | 2785 | if (dev->towrite) { |
a4456856 | 2786 | s.to_write++; |
1da177e4 | 2787 | if (!test_bit(R5_OVERWRITE, &dev->flags)) |
a4456856 | 2788 | s.non_overwrite++; |
1da177e4 | 2789 | } |
a4456856 DW |
2790 | if (dev->written) |
2791 | s.written++; | |
9910f16a | 2792 | rdev = rcu_dereference(conf->disks[i].rdev); |
ac4090d2 N |
2793 | if (blocked_rdev == NULL && |
2794 | rdev && unlikely(test_bit(Blocked, &rdev->flags))) { | |
6bfe0b49 DW |
2795 | blocked_rdev = rdev; |
2796 | atomic_inc(&rdev->nr_pending); | |
6bfe0b49 | 2797 | } |
b2d444d7 | 2798 | if (!rdev || !test_bit(In_sync, &rdev->flags)) { |
14f8d26b | 2799 | /* The ReadError flag will just be confusing now */ |
4e5314b5 N |
2800 | clear_bit(R5_ReadError, &dev->flags); |
2801 | clear_bit(R5_ReWrite, &dev->flags); | |
2802 | } | |
b2d444d7 | 2803 | if (!rdev || !test_bit(In_sync, &rdev->flags) |
4e5314b5 | 2804 | || test_bit(R5_ReadError, &dev->flags)) { |
a4456856 DW |
2805 | s.failed++; |
2806 | s.failed_num = i; | |
1da177e4 LT |
2807 | } else |
2808 | set_bit(R5_Insync, &dev->flags); | |
2809 | } | |
9910f16a | 2810 | rcu_read_unlock(); |
b5e98d65 | 2811 | |
6bfe0b49 | 2812 | if (unlikely(blocked_rdev)) { |
ac4090d2 N |
2813 | if (s.syncing || s.expanding || s.expanded || |
2814 | s.to_write || s.written) { | |
2815 | set_bit(STRIPE_HANDLE, &sh->state); | |
2816 | goto unlock; | |
2817 | } | |
2818 | /* There is nothing for the blocked_rdev to block */ | |
2819 | rdev_dec_pending(blocked_rdev, conf->mddev); | |
2820 | blocked_rdev = NULL; | |
6bfe0b49 DW |
2821 | } |
2822 | ||
83de75cc DW |
2823 | if (s.to_fill && !test_bit(STRIPE_BIOFILL_RUN, &sh->state)) { |
2824 | set_bit(STRIPE_OP_BIOFILL, &s.ops_request); | |
2825 | set_bit(STRIPE_BIOFILL_RUN, &sh->state); | |
2826 | } | |
b5e98d65 | 2827 | |
45b4233c | 2828 | pr_debug("locked=%d uptodate=%d to_read=%d" |
1da177e4 | 2829 | " to_write=%d failed=%d failed_num=%d\n", |
a4456856 DW |
2830 | s.locked, s.uptodate, s.to_read, s.to_write, |
2831 | s.failed, s.failed_num); | |
1da177e4 LT |
2832 | /* check if the array has lost two devices and, if so, some requests might |
2833 | * need to be failed | |
2834 | */ | |
a4456856 | 2835 | if (s.failed > 1 && s.to_read+s.to_write+s.written) |
1fe797e6 | 2836 | handle_failed_stripe(conf, sh, &s, disks, &return_bi); |
a4456856 | 2837 | if (s.failed > 1 && s.syncing) { |
1da177e4 LT |
2838 | md_done_sync(conf->mddev, STRIPE_SECTORS,0); |
2839 | clear_bit(STRIPE_SYNCING, &sh->state); | |
a4456856 | 2840 | s.syncing = 0; |
1da177e4 LT |
2841 | } |
2842 | ||
2843 | /* might be able to return some write requests if the parity block | |
2844 | * is safe, or on a failed drive | |
2845 | */ | |
2846 | dev = &sh->dev[sh->pd_idx]; | |
a4456856 DW |
2847 | if ( s.written && |
2848 | ((test_bit(R5_Insync, &dev->flags) && | |
2849 | !test_bit(R5_LOCKED, &dev->flags) && | |
2850 | test_bit(R5_UPTODATE, &dev->flags)) || | |
2851 | (s.failed == 1 && s.failed_num == sh->pd_idx))) | |
1fe797e6 | 2852 | handle_stripe_clean_event(conf, sh, disks, &return_bi); |
1da177e4 LT |
2853 | |
2854 | /* Now we might consider reading some blocks, either to check/generate | |
2855 | * parity, or to satisfy requests | |
2856 | * or to load a block that is being partially written. | |
2857 | */ | |
a4456856 | 2858 | if (s.to_read || s.non_overwrite || |
976ea8d4 | 2859 | (s.syncing && (s.uptodate + s.compute < disks)) || s.expanding) |
1fe797e6 | 2860 | handle_stripe_fill5(sh, &s, disks); |
1da177e4 | 2861 | |
e33129d8 DW |
2862 | /* Now we check to see if any write operations have recently |
2863 | * completed | |
2864 | */ | |
e0a115e5 | 2865 | prexor = 0; |
d8ee0728 | 2866 | if (sh->reconstruct_state == reconstruct_state_prexor_drain_result) |
e0a115e5 | 2867 | prexor = 1; |
d8ee0728 DW |
2868 | if (sh->reconstruct_state == reconstruct_state_drain_result || |
2869 | sh->reconstruct_state == reconstruct_state_prexor_drain_result) { | |
600aa109 | 2870 | sh->reconstruct_state = reconstruct_state_idle; |
e33129d8 DW |
2871 | |
2872 | /* All the 'written' buffers and the parity block are ready to | |
2873 | * be written back to disk | |
2874 | */ | |
2875 | BUG_ON(!test_bit(R5_UPTODATE, &sh->dev[sh->pd_idx].flags)); | |
2876 | for (i = disks; i--; ) { | |
2877 | dev = &sh->dev[i]; | |
2878 | if (test_bit(R5_LOCKED, &dev->flags) && | |
2879 | (i == sh->pd_idx || dev->written)) { | |
2880 | pr_debug("Writing block %d\n", i); | |
2881 | set_bit(R5_Wantwrite, &dev->flags); | |
e0a115e5 DW |
2882 | if (prexor) |
2883 | continue; | |
e33129d8 DW |
2884 | if (!test_bit(R5_Insync, &dev->flags) || |
2885 | (i == sh->pd_idx && s.failed == 0)) | |
2886 | set_bit(STRIPE_INSYNC, &sh->state); | |
2887 | } | |
2888 | } | |
2889 | if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
2890 | atomic_dec(&conf->preread_active_stripes); | |
2891 | if (atomic_read(&conf->preread_active_stripes) < | |
2892 | IO_THRESHOLD) | |
2893 | md_wakeup_thread(conf->mddev->thread); | |
2894 | } | |
2895 | } | |
2896 | ||
2897 | /* Now to consider new write requests and what else, if anything | |
2898 | * should be read. We do not handle new writes when: | |
2899 | * 1/ A 'write' operation (copy+xor) is already in flight. | |
2900 | * 2/ A 'check' operation is in flight, as it may clobber the parity | |
2901 | * block. | |
2902 | */ | |
600aa109 | 2903 | if (s.to_write && !sh->reconstruct_state && !sh->check_state) |
1fe797e6 | 2904 | handle_stripe_dirtying5(conf, sh, &s, disks); |
1da177e4 LT |
2905 | |
2906 | /* maybe we need to check and possibly fix the parity for this stripe | |
e89f8962 DW |
2907 | * Any reads will already have been scheduled, so we just see if enough |
2908 | * data is available. The parity check is held off while parity | |
2909 | * dependent operations are in flight. | |
1da177e4 | 2910 | */ |
ecc65c9b DW |
2911 | if (sh->check_state || |
2912 | (s.syncing && s.locked == 0 && | |
976ea8d4 | 2913 | !test_bit(STRIPE_COMPUTE_RUN, &sh->state) && |
ecc65c9b | 2914 | !test_bit(STRIPE_INSYNC, &sh->state))) |
a4456856 | 2915 | handle_parity_checks5(conf, sh, &s, disks); |
e89f8962 | 2916 | |
a4456856 | 2917 | if (s.syncing && s.locked == 0 && test_bit(STRIPE_INSYNC, &sh->state)) { |
1da177e4 LT |
2918 | md_done_sync(conf->mddev, STRIPE_SECTORS,1); |
2919 | clear_bit(STRIPE_SYNCING, &sh->state); | |
2920 | } | |
4e5314b5 N |
2921 | |
2922 | /* If the failed drive is just a ReadError, then we might need to progress | |
2923 | * the repair/check process | |
2924 | */ | |
a4456856 DW |
2925 | if (s.failed == 1 && !conf->mddev->ro && |
2926 | test_bit(R5_ReadError, &sh->dev[s.failed_num].flags) | |
2927 | && !test_bit(R5_LOCKED, &sh->dev[s.failed_num].flags) | |
2928 | && test_bit(R5_UPTODATE, &sh->dev[s.failed_num].flags) | |
4e5314b5 | 2929 | ) { |
a4456856 | 2930 | dev = &sh->dev[s.failed_num]; |
4e5314b5 N |
2931 | if (!test_bit(R5_ReWrite, &dev->flags)) { |
2932 | set_bit(R5_Wantwrite, &dev->flags); | |
2933 | set_bit(R5_ReWrite, &dev->flags); | |
2934 | set_bit(R5_LOCKED, &dev->flags); | |
a4456856 | 2935 | s.locked++; |
4e5314b5 N |
2936 | } else { |
2937 | /* let's read it back */ | |
2938 | set_bit(R5_Wantread, &dev->flags); | |
2939 | set_bit(R5_LOCKED, &dev->flags); | |
a4456856 | 2940 | s.locked++; |
4e5314b5 N |
2941 | } |
2942 | } | |
2943 | ||
600aa109 DW |
2944 | /* Finish reconstruct operations initiated by the expansion process */ |
2945 | if (sh->reconstruct_state == reconstruct_state_result) { | |
ab69ae12 N |
2946 | struct stripe_head *sh2 |
2947 | = get_active_stripe(conf, sh->sector, 1, 1); | |
2948 | if (sh2 && test_bit(STRIPE_EXPAND_SOURCE, &sh2->state)) { | |
2949 | /* sh cannot be written until sh2 has been read. | |
2950 | * so arrange for sh to be delayed a little | |
2951 | */ | |
2952 | set_bit(STRIPE_DELAYED, &sh->state); | |
2953 | set_bit(STRIPE_HANDLE, &sh->state); | |
2954 | if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE, | |
2955 | &sh2->state)) | |
2956 | atomic_inc(&conf->preread_active_stripes); | |
2957 | release_stripe(sh2); | |
2958 | goto unlock; | |
2959 | } | |
2960 | if (sh2) | |
2961 | release_stripe(sh2); | |
2962 | ||
600aa109 | 2963 | sh->reconstruct_state = reconstruct_state_idle; |
f0a50d37 | 2964 | clear_bit(STRIPE_EXPANDING, &sh->state); |
23397883 | 2965 | for (i = conf->raid_disks; i--; ) { |
ccfcc3c1 | 2966 | set_bit(R5_Wantwrite, &sh->dev[i].flags); |
23397883 | 2967 | set_bit(R5_LOCKED, &sh->dev[i].flags); |
efe31143 | 2968 | s.locked++; |
23397883 | 2969 | } |
f0a50d37 DW |
2970 | } |
2971 | ||
2972 | if (s.expanded && test_bit(STRIPE_EXPANDING, &sh->state) && | |
600aa109 | 2973 | !sh->reconstruct_state) { |
f0a50d37 DW |
2974 | /* Need to write out all blocks after computing parity */ |
2975 | sh->disks = conf->raid_disks; | |
911d4ee8 | 2976 | stripe_set_idx(sh->sector, conf, 0, sh); |
1fe797e6 | 2977 | schedule_reconstruction5(sh, &s, 1, 1); |
600aa109 | 2978 | } else if (s.expanded && !sh->reconstruct_state && s.locked == 0) { |
ccfcc3c1 | 2979 | clear_bit(STRIPE_EXPAND_READY, &sh->state); |
f6705578 | 2980 | atomic_dec(&conf->reshape_stripes); |
ccfcc3c1 N |
2981 | wake_up(&conf->wait_for_overlap); |
2982 | md_done_sync(conf->mddev, STRIPE_SECTORS, 1); | |
2983 | } | |
2984 | ||
0f94e87c | 2985 | if (s.expanding && s.locked == 0 && |
976ea8d4 | 2986 | !test_bit(STRIPE_COMPUTE_RUN, &sh->state)) |
a4456856 | 2987 | handle_stripe_expansion(conf, sh, NULL); |
ccfcc3c1 | 2988 | |
6bfe0b49 | 2989 | unlock: |
1da177e4 LT |
2990 | spin_unlock(&sh->lock); |
2991 | ||
6bfe0b49 DW |
2992 | /* wait for this device to become unblocked */ |
2993 | if (unlikely(blocked_rdev)) | |
2994 | md_wait_for_blocked_rdev(blocked_rdev, conf->mddev); | |
2995 | ||
600aa109 DW |
2996 | if (s.ops_request) |
2997 | raid5_run_ops(sh, s.ops_request); | |
d84e0f10 | 2998 | |
c4e5ac0a | 2999 | ops_run_io(sh, &s); |
1da177e4 | 3000 | |
a4456856 | 3001 | return_io(return_bi); |
df10cfbc DW |
3002 | |
3003 | return blocked_rdev == NULL; | |
1da177e4 LT |
3004 | } |
3005 | ||
df10cfbc | 3006 | static bool handle_stripe6(struct stripe_head *sh, struct page *tmp_page) |
1da177e4 | 3007 | { |
bff61975 | 3008 | raid5_conf_t *conf = sh->raid_conf; |
f416885e | 3009 | int disks = sh->disks; |
a4456856 | 3010 | struct bio *return_bi = NULL; |
34e04e87 | 3011 | int i, pd_idx = sh->pd_idx, qd_idx = sh->qd_idx; |
a4456856 DW |
3012 | struct stripe_head_state s; |
3013 | struct r6_state r6s; | |
16a53ecc | 3014 | struct r5dev *dev, *pdev, *qdev; |
6bfe0b49 | 3015 | mdk_rdev_t *blocked_rdev = NULL; |
1da177e4 | 3016 | |
45b4233c | 3017 | pr_debug("handling stripe %llu, state=%#lx cnt=%d, " |
a4456856 DW |
3018 | "pd_idx=%d, qd_idx=%d\n", |
3019 | (unsigned long long)sh->sector, sh->state, | |
34e04e87 | 3020 | atomic_read(&sh->count), pd_idx, qd_idx); |
a4456856 | 3021 | memset(&s, 0, sizeof(s)); |
72626685 | 3022 | |
16a53ecc N |
3023 | spin_lock(&sh->lock); |
3024 | clear_bit(STRIPE_HANDLE, &sh->state); | |
3025 | clear_bit(STRIPE_DELAYED, &sh->state); | |
3026 | ||
a4456856 DW |
3027 | s.syncing = test_bit(STRIPE_SYNCING, &sh->state); |
3028 | s.expanding = test_bit(STRIPE_EXPAND_SOURCE, &sh->state); | |
3029 | s.expanded = test_bit(STRIPE_EXPAND_READY, &sh->state); | |
16a53ecc | 3030 | /* Now to look around and see what can be done */ |
1da177e4 LT |
3031 | |
3032 | rcu_read_lock(); | |
16a53ecc N |
3033 | for (i=disks; i--; ) { |
3034 | mdk_rdev_t *rdev; | |
3035 | dev = &sh->dev[i]; | |
3036 | clear_bit(R5_Insync, &dev->flags); | |
1da177e4 | 3037 | |
45b4233c | 3038 | pr_debug("check %d: state 0x%lx read %p write %p written %p\n", |
16a53ecc N |
3039 | i, dev->flags, dev->toread, dev->towrite, dev->written); |
3040 | /* maybe we can reply to a read */ | |
3041 | if (test_bit(R5_UPTODATE, &dev->flags) && dev->toread) { | |
3042 | struct bio *rbi, *rbi2; | |
45b4233c | 3043 | pr_debug("Return read for disc %d\n", i); |
16a53ecc N |
3044 | spin_lock_irq(&conf->device_lock); |
3045 | rbi = dev->toread; | |
3046 | dev->toread = NULL; | |
3047 | if (test_and_clear_bit(R5_Overlap, &dev->flags)) | |
3048 | wake_up(&conf->wait_for_overlap); | |
3049 | spin_unlock_irq(&conf->device_lock); | |
3050 | while (rbi && rbi->bi_sector < dev->sector + STRIPE_SECTORS) { | |
3051 | copy_data(0, rbi, dev->page, dev->sector); | |
3052 | rbi2 = r5_next_bio(rbi, dev->sector); | |
3053 | spin_lock_irq(&conf->device_lock); | |
960e739d | 3054 | if (!raid5_dec_bi_phys_segments(rbi)) { |
16a53ecc N |
3055 | rbi->bi_next = return_bi; |
3056 | return_bi = rbi; | |
3057 | } | |
3058 | spin_unlock_irq(&conf->device_lock); | |
3059 | rbi = rbi2; | |
3060 | } | |
3061 | } | |
1da177e4 | 3062 | |
16a53ecc | 3063 | /* now count some things */ |
a4456856 DW |
3064 | if (test_bit(R5_LOCKED, &dev->flags)) s.locked++; |
3065 | if (test_bit(R5_UPTODATE, &dev->flags)) s.uptodate++; | |
1da177e4 | 3066 | |
16a53ecc | 3067 | |
a4456856 DW |
3068 | if (dev->toread) |
3069 | s.to_read++; | |
16a53ecc | 3070 | if (dev->towrite) { |
a4456856 | 3071 | s.to_write++; |
16a53ecc | 3072 | if (!test_bit(R5_OVERWRITE, &dev->flags)) |
a4456856 | 3073 | s.non_overwrite++; |
16a53ecc | 3074 | } |
a4456856 DW |
3075 | if (dev->written) |
3076 | s.written++; | |
16a53ecc | 3077 | rdev = rcu_dereference(conf->disks[i].rdev); |
ac4090d2 N |
3078 | if (blocked_rdev == NULL && |
3079 | rdev && unlikely(test_bit(Blocked, &rdev->flags))) { | |
6bfe0b49 DW |
3080 | blocked_rdev = rdev; |
3081 | atomic_inc(&rdev->nr_pending); | |
6bfe0b49 | 3082 | } |
16a53ecc N |
3083 | if (!rdev || !test_bit(In_sync, &rdev->flags)) { |
3084 | /* The ReadError flag will just be confusing now */ | |
3085 | clear_bit(R5_ReadError, &dev->flags); | |
3086 | clear_bit(R5_ReWrite, &dev->flags); | |
1da177e4 | 3087 | } |
16a53ecc N |
3088 | if (!rdev || !test_bit(In_sync, &rdev->flags) |
3089 | || test_bit(R5_ReadError, &dev->flags)) { | |
a4456856 DW |
3090 | if (s.failed < 2) |
3091 | r6s.failed_num[s.failed] = i; | |
3092 | s.failed++; | |
16a53ecc N |
3093 | } else |
3094 | set_bit(R5_Insync, &dev->flags); | |
1da177e4 LT |
3095 | } |
3096 | rcu_read_unlock(); | |
6bfe0b49 DW |
3097 | |
3098 | if (unlikely(blocked_rdev)) { | |
ac4090d2 N |
3099 | if (s.syncing || s.expanding || s.expanded || |
3100 | s.to_write || s.written) { | |
3101 | set_bit(STRIPE_HANDLE, &sh->state); | |
3102 | goto unlock; | |
3103 | } | |
3104 | /* There is nothing for the blocked_rdev to block */ | |
3105 | rdev_dec_pending(blocked_rdev, conf->mddev); | |
3106 | blocked_rdev = NULL; | |
6bfe0b49 | 3107 | } |
ac4090d2 | 3108 | |
45b4233c | 3109 | pr_debug("locked=%d uptodate=%d to_read=%d" |
16a53ecc | 3110 | " to_write=%d failed=%d failed_num=%d,%d\n", |
a4456856 DW |
3111 | s.locked, s.uptodate, s.to_read, s.to_write, s.failed, |
3112 | r6s.failed_num[0], r6s.failed_num[1]); | |
3113 | /* check if the array has lost >2 devices and, if so, some requests | |
3114 | * might need to be failed | |
16a53ecc | 3115 | */ |
a4456856 | 3116 | if (s.failed > 2 && s.to_read+s.to_write+s.written) |
1fe797e6 | 3117 | handle_failed_stripe(conf, sh, &s, disks, &return_bi); |
a4456856 | 3118 | if (s.failed > 2 && s.syncing) { |
16a53ecc N |
3119 | md_done_sync(conf->mddev, STRIPE_SECTORS,0); |
3120 | clear_bit(STRIPE_SYNCING, &sh->state); | |
a4456856 | 3121 | s.syncing = 0; |
16a53ecc N |
3122 | } |
3123 | ||
3124 | /* | |
3125 | * might be able to return some write requests if the parity blocks | |
3126 | * are safe, or on a failed drive | |
3127 | */ | |
3128 | pdev = &sh->dev[pd_idx]; | |
a4456856 DW |
3129 | r6s.p_failed = (s.failed >= 1 && r6s.failed_num[0] == pd_idx) |
3130 | || (s.failed >= 2 && r6s.failed_num[1] == pd_idx); | |
34e04e87 N |
3131 | qdev = &sh->dev[qd_idx]; |
3132 | r6s.q_failed = (s.failed >= 1 && r6s.failed_num[0] == qd_idx) | |
3133 | || (s.failed >= 2 && r6s.failed_num[1] == qd_idx); | |
a4456856 DW |
3134 | |
3135 | if ( s.written && | |
3136 | ( r6s.p_failed || ((test_bit(R5_Insync, &pdev->flags) | |
16a53ecc | 3137 | && !test_bit(R5_LOCKED, &pdev->flags) |
a4456856 DW |
3138 | && test_bit(R5_UPTODATE, &pdev->flags)))) && |
3139 | ( r6s.q_failed || ((test_bit(R5_Insync, &qdev->flags) | |
16a53ecc | 3140 | && !test_bit(R5_LOCKED, &qdev->flags) |
a4456856 | 3141 | && test_bit(R5_UPTODATE, &qdev->flags))))) |
1fe797e6 | 3142 | handle_stripe_clean_event(conf, sh, disks, &return_bi); |
16a53ecc N |
3143 | |
3144 | /* Now we might consider reading some blocks, either to check/generate | |
3145 | * parity, or to satisfy requests | |
3146 | * or to load a block that is being partially written. | |
3147 | */ | |
a4456856 DW |
3148 | if (s.to_read || s.non_overwrite || (s.to_write && s.failed) || |
3149 | (s.syncing && (s.uptodate < disks)) || s.expanding) | |
1fe797e6 | 3150 | handle_stripe_fill6(sh, &s, &r6s, disks); |
16a53ecc N |
3151 | |
3152 | /* now to consider writing and what else, if anything should be read */ | |
a4456856 | 3153 | if (s.to_write) |
1fe797e6 | 3154 | handle_stripe_dirtying6(conf, sh, &s, &r6s, disks); |
16a53ecc N |
3155 | |
3156 | /* maybe we need to check and possibly fix the parity for this stripe | |
a4456856 DW |
3157 | * Any reads will already have been scheduled, so we just see if enough |
3158 | * data is available | |
16a53ecc | 3159 | */ |
a4456856 DW |
3160 | if (s.syncing && s.locked == 0 && !test_bit(STRIPE_INSYNC, &sh->state)) |
3161 | handle_parity_checks6(conf, sh, &s, &r6s, tmp_page, disks); | |
16a53ecc | 3162 | |
a4456856 | 3163 | if (s.syncing && s.locked == 0 && test_bit(STRIPE_INSYNC, &sh->state)) { |
16a53ecc N |
3164 | md_done_sync(conf->mddev, STRIPE_SECTORS,1); |
3165 | clear_bit(STRIPE_SYNCING, &sh->state); | |
3166 | } | |
3167 | ||
3168 | /* If the failed drives are just a ReadError, then we might need | |
3169 | * to progress the repair/check process | |
3170 | */ | |
a4456856 DW |
3171 | if (s.failed <= 2 && !conf->mddev->ro) |
3172 | for (i = 0; i < s.failed; i++) { | |
3173 | dev = &sh->dev[r6s.failed_num[i]]; | |
16a53ecc N |
3174 | if (test_bit(R5_ReadError, &dev->flags) |
3175 | && !test_bit(R5_LOCKED, &dev->flags) | |
3176 | && test_bit(R5_UPTODATE, &dev->flags) | |
3177 | ) { | |
3178 | if (!test_bit(R5_ReWrite, &dev->flags)) { | |
3179 | set_bit(R5_Wantwrite, &dev->flags); | |
3180 | set_bit(R5_ReWrite, &dev->flags); | |
3181 | set_bit(R5_LOCKED, &dev->flags); | |
3182 | } else { | |
3183 | /* let's read it back */ | |
3184 | set_bit(R5_Wantread, &dev->flags); | |
3185 | set_bit(R5_LOCKED, &dev->flags); | |
3186 | } | |
3187 | } | |
3188 | } | |
f416885e | 3189 | |
a4456856 | 3190 | if (s.expanded && test_bit(STRIPE_EXPANDING, &sh->state)) { |
ab69ae12 N |
3191 | struct stripe_head *sh2 |
3192 | = get_active_stripe(conf, sh->sector, 1, 1); | |
3193 | if (sh2 && test_bit(STRIPE_EXPAND_SOURCE, &sh2->state)) { | |
3194 | /* sh cannot be written until sh2 has been read. | |
3195 | * so arrange for sh to be delayed a little | |
3196 | */ | |
3197 | set_bit(STRIPE_DELAYED, &sh->state); | |
3198 | set_bit(STRIPE_HANDLE, &sh->state); | |
3199 | if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE, | |
3200 | &sh2->state)) | |
3201 | atomic_inc(&conf->preread_active_stripes); | |
3202 | release_stripe(sh2); | |
3203 | goto unlock; | |
3204 | } | |
3205 | if (sh2) | |
3206 | release_stripe(sh2); | |
3207 | ||
f416885e N |
3208 | /* Need to write out all blocks after computing P&Q */ |
3209 | sh->disks = conf->raid_disks; | |
911d4ee8 | 3210 | stripe_set_idx(sh->sector, conf, 0, sh); |
f416885e N |
3211 | compute_parity6(sh, RECONSTRUCT_WRITE); |
3212 | for (i = conf->raid_disks ; i-- ; ) { | |
3213 | set_bit(R5_LOCKED, &sh->dev[i].flags); | |
a4456856 | 3214 | s.locked++; |
f416885e N |
3215 | set_bit(R5_Wantwrite, &sh->dev[i].flags); |
3216 | } | |
3217 | clear_bit(STRIPE_EXPANDING, &sh->state); | |
a4456856 | 3218 | } else if (s.expanded) { |
f416885e N |
3219 | clear_bit(STRIPE_EXPAND_READY, &sh->state); |
3220 | atomic_dec(&conf->reshape_stripes); | |
3221 | wake_up(&conf->wait_for_overlap); | |
3222 | md_done_sync(conf->mddev, STRIPE_SECTORS, 1); | |
3223 | } | |
3224 | ||
0f94e87c | 3225 | if (s.expanding && s.locked == 0 && |
976ea8d4 | 3226 | !test_bit(STRIPE_COMPUTE_RUN, &sh->state)) |
a4456856 | 3227 | handle_stripe_expansion(conf, sh, &r6s); |
f416885e | 3228 | |
6bfe0b49 | 3229 | unlock: |
16a53ecc N |
3230 | spin_unlock(&sh->lock); |
3231 | ||
6bfe0b49 DW |
3232 | /* wait for this device to become unblocked */ |
3233 | if (unlikely(blocked_rdev)) | |
3234 | md_wait_for_blocked_rdev(blocked_rdev, conf->mddev); | |
3235 | ||
f0e43bcd | 3236 | ops_run_io(sh, &s); |
16a53ecc | 3237 | |
f0e43bcd | 3238 | return_io(return_bi); |
df10cfbc DW |
3239 | |
3240 | return blocked_rdev == NULL; | |
16a53ecc N |
3241 | } |
3242 | ||
df10cfbc DW |
3243 | /* returns true if the stripe was handled */ |
3244 | static bool handle_stripe(struct stripe_head *sh, struct page *tmp_page) | |
16a53ecc N |
3245 | { |
3246 | if (sh->raid_conf->level == 6) | |
df10cfbc | 3247 | return handle_stripe6(sh, tmp_page); |
16a53ecc | 3248 | else |
df10cfbc | 3249 | return handle_stripe5(sh); |
16a53ecc N |
3250 | } |
3251 | ||
3252 | ||
3253 | ||
3254 | static void raid5_activate_delayed(raid5_conf_t *conf) | |
3255 | { | |
3256 | if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD) { | |
3257 | while (!list_empty(&conf->delayed_list)) { | |
3258 | struct list_head *l = conf->delayed_list.next; | |
3259 | struct stripe_head *sh; | |
3260 | sh = list_entry(l, struct stripe_head, lru); | |
3261 | list_del_init(l); | |
3262 | clear_bit(STRIPE_DELAYED, &sh->state); | |
3263 | if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) | |
3264 | atomic_inc(&conf->preread_active_stripes); | |
8b3e6cdc | 3265 | list_add_tail(&sh->lru, &conf->hold_list); |
16a53ecc | 3266 | } |
6ed3003c N |
3267 | } else |
3268 | blk_plug_device(conf->mddev->queue); | |
16a53ecc N |
3269 | } |
3270 | ||
3271 | static void activate_bit_delay(raid5_conf_t *conf) | |
3272 | { | |
3273 | /* device_lock is held */ | |
3274 | struct list_head head; | |
3275 | list_add(&head, &conf->bitmap_list); | |
3276 | list_del_init(&conf->bitmap_list); | |
3277 | while (!list_empty(&head)) { | |
3278 | struct stripe_head *sh = list_entry(head.next, struct stripe_head, lru); | |
3279 | list_del_init(&sh->lru); | |
3280 | atomic_inc(&sh->count); | |
3281 | __release_stripe(conf, sh); | |
3282 | } | |
3283 | } | |
3284 | ||
3285 | static void unplug_slaves(mddev_t *mddev) | |
3286 | { | |
3287 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
3288 | int i; | |
3289 | ||
3290 | rcu_read_lock(); | |
3291 | for (i=0; i<mddev->raid_disks; i++) { | |
3292 | mdk_rdev_t *rdev = rcu_dereference(conf->disks[i].rdev); | |
3293 | if (rdev && !test_bit(Faulty, &rdev->flags) && atomic_read(&rdev->nr_pending)) { | |
165125e1 | 3294 | struct request_queue *r_queue = bdev_get_queue(rdev->bdev); |
16a53ecc N |
3295 | |
3296 | atomic_inc(&rdev->nr_pending); | |
3297 | rcu_read_unlock(); | |
3298 | ||
2ad8b1ef | 3299 | blk_unplug(r_queue); |
16a53ecc N |
3300 | |
3301 | rdev_dec_pending(rdev, mddev); | |
3302 | rcu_read_lock(); | |
3303 | } | |
3304 | } | |
3305 | rcu_read_unlock(); | |
3306 | } | |
3307 | ||
165125e1 | 3308 | static void raid5_unplug_device(struct request_queue *q) |
16a53ecc N |
3309 | { |
3310 | mddev_t *mddev = q->queuedata; | |
3311 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
3312 | unsigned long flags; | |
3313 | ||
3314 | spin_lock_irqsave(&conf->device_lock, flags); | |
3315 | ||
3316 | if (blk_remove_plug(q)) { | |
3317 | conf->seq_flush++; | |
3318 | raid5_activate_delayed(conf); | |
72626685 | 3319 | } |
1da177e4 LT |
3320 | md_wakeup_thread(mddev->thread); |
3321 | ||
3322 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
3323 | ||
3324 | unplug_slaves(mddev); | |
3325 | } | |
3326 | ||
f022b2fd N |
3327 | static int raid5_congested(void *data, int bits) |
3328 | { | |
3329 | mddev_t *mddev = data; | |
3330 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
3331 | ||
3332 | /* No difference between reads and writes. Just check | |
3333 | * how busy the stripe_cache is | |
3334 | */ | |
3335 | if (conf->inactive_blocked) | |
3336 | return 1; | |
3337 | if (conf->quiesce) | |
3338 | return 1; | |
3339 | if (list_empty_careful(&conf->inactive_list)) | |
3340 | return 1; | |
3341 | ||
3342 | return 0; | |
3343 | } | |
3344 | ||
23032a0e RBJ |
3345 | /* We want read requests to align with chunks where possible, |
3346 | * but write requests don't need to. | |
3347 | */ | |
cc371e66 AK |
3348 | static int raid5_mergeable_bvec(struct request_queue *q, |
3349 | struct bvec_merge_data *bvm, | |
3350 | struct bio_vec *biovec) | |
23032a0e RBJ |
3351 | { |
3352 | mddev_t *mddev = q->queuedata; | |
cc371e66 | 3353 | sector_t sector = bvm->bi_sector + get_start_sect(bvm->bi_bdev); |
23032a0e RBJ |
3354 | int max; |
3355 | unsigned int chunk_sectors = mddev->chunk_size >> 9; | |
cc371e66 | 3356 | unsigned int bio_sectors = bvm->bi_size >> 9; |
23032a0e | 3357 | |
cc371e66 | 3358 | if ((bvm->bi_rw & 1) == WRITE) |
23032a0e RBJ |
3359 | return biovec->bv_len; /* always allow writes to be mergeable */ |
3360 | ||
784052ec N |
3361 | if (mddev->new_chunk < mddev->chunk_size) |
3362 | chunk_sectors = mddev->new_chunk >> 9; | |
23032a0e RBJ |
3363 | max = (chunk_sectors - ((sector & (chunk_sectors - 1)) + bio_sectors)) << 9; |
3364 | if (max < 0) max = 0; | |
3365 | if (max <= biovec->bv_len && bio_sectors == 0) | |
3366 | return biovec->bv_len; | |
3367 | else | |
3368 | return max; | |
3369 | } | |
3370 | ||
f679623f RBJ |
3371 | |
3372 | static int in_chunk_boundary(mddev_t *mddev, struct bio *bio) | |
3373 | { | |
3374 | sector_t sector = bio->bi_sector + get_start_sect(bio->bi_bdev); | |
3375 | unsigned int chunk_sectors = mddev->chunk_size >> 9; | |
3376 | unsigned int bio_sectors = bio->bi_size >> 9; | |
3377 | ||
784052ec N |
3378 | if (mddev->new_chunk < mddev->chunk_size) |
3379 | chunk_sectors = mddev->new_chunk >> 9; | |
f679623f RBJ |
3380 | return chunk_sectors >= |
3381 | ((sector & (chunk_sectors - 1)) + bio_sectors); | |
3382 | } | |
3383 | ||
46031f9a RBJ |
3384 | /* |
3385 | * add bio to the retry LIFO ( in O(1) ... we are in interrupt ) | |
3386 | * later sampled by raid5d. | |
3387 | */ | |
3388 | static void add_bio_to_retry(struct bio *bi,raid5_conf_t *conf) | |
3389 | { | |
3390 | unsigned long flags; | |
3391 | ||
3392 | spin_lock_irqsave(&conf->device_lock, flags); | |
3393 | ||
3394 | bi->bi_next = conf->retry_read_aligned_list; | |
3395 | conf->retry_read_aligned_list = bi; | |
3396 | ||
3397 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
3398 | md_wakeup_thread(conf->mddev->thread); | |
3399 | } | |
3400 | ||
3401 | ||
3402 | static struct bio *remove_bio_from_retry(raid5_conf_t *conf) | |
3403 | { | |
3404 | struct bio *bi; | |
3405 | ||
3406 | bi = conf->retry_read_aligned; | |
3407 | if (bi) { | |
3408 | conf->retry_read_aligned = NULL; | |
3409 | return bi; | |
3410 | } | |
3411 | bi = conf->retry_read_aligned_list; | |
3412 | if(bi) { | |
387bb173 | 3413 | conf->retry_read_aligned_list = bi->bi_next; |
46031f9a | 3414 | bi->bi_next = NULL; |
960e739d JA |
3415 | /* |
3416 | * this sets the active strip count to 1 and the processed | |
3417 | * strip count to zero (upper 8 bits) | |
3418 | */ | |
46031f9a | 3419 | bi->bi_phys_segments = 1; /* biased count of active stripes */ |
46031f9a RBJ |
3420 | } |
3421 | ||
3422 | return bi; | |
3423 | } | |
3424 | ||
3425 | ||
f679623f RBJ |
3426 | /* |
3427 | * The "raid5_align_endio" should check if the read succeeded and if it | |
3428 | * did, call bio_endio on the original bio (having bio_put the new bio | |
3429 | * first). | |
3430 | * If the read failed.. | |
3431 | */ | |
6712ecf8 | 3432 | static void raid5_align_endio(struct bio *bi, int error) |
f679623f RBJ |
3433 | { |
3434 | struct bio* raid_bi = bi->bi_private; | |
46031f9a RBJ |
3435 | mddev_t *mddev; |
3436 | raid5_conf_t *conf; | |
3437 | int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags); | |
3438 | mdk_rdev_t *rdev; | |
3439 | ||
f679623f | 3440 | bio_put(bi); |
46031f9a RBJ |
3441 | |
3442 | mddev = raid_bi->bi_bdev->bd_disk->queue->queuedata; | |
3443 | conf = mddev_to_conf(mddev); | |
3444 | rdev = (void*)raid_bi->bi_next; | |
3445 | raid_bi->bi_next = NULL; | |
3446 | ||
3447 | rdev_dec_pending(rdev, conf->mddev); | |
3448 | ||
3449 | if (!error && uptodate) { | |
6712ecf8 | 3450 | bio_endio(raid_bi, 0); |
46031f9a RBJ |
3451 | if (atomic_dec_and_test(&conf->active_aligned_reads)) |
3452 | wake_up(&conf->wait_for_stripe); | |
6712ecf8 | 3453 | return; |
46031f9a RBJ |
3454 | } |
3455 | ||
3456 | ||
45b4233c | 3457 | pr_debug("raid5_align_endio : io error...handing IO for a retry\n"); |
46031f9a RBJ |
3458 | |
3459 | add_bio_to_retry(raid_bi, conf); | |
f679623f RBJ |
3460 | } |
3461 | ||
387bb173 NB |
3462 | static int bio_fits_rdev(struct bio *bi) |
3463 | { | |
165125e1 | 3464 | struct request_queue *q = bdev_get_queue(bi->bi_bdev); |
387bb173 NB |
3465 | |
3466 | if ((bi->bi_size>>9) > q->max_sectors) | |
3467 | return 0; | |
3468 | blk_recount_segments(q, bi); | |
960e739d | 3469 | if (bi->bi_phys_segments > q->max_phys_segments) |
387bb173 NB |
3470 | return 0; |
3471 | ||
3472 | if (q->merge_bvec_fn) | |
3473 | /* it's too hard to apply the merge_bvec_fn at this stage, | |
3474 | * just just give up | |
3475 | */ | |
3476 | return 0; | |
3477 | ||
3478 | return 1; | |
3479 | } | |
3480 | ||
3481 | ||
165125e1 | 3482 | static int chunk_aligned_read(struct request_queue *q, struct bio * raid_bio) |
f679623f RBJ |
3483 | { |
3484 | mddev_t *mddev = q->queuedata; | |
3485 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
911d4ee8 | 3486 | unsigned int dd_idx; |
f679623f RBJ |
3487 | struct bio* align_bi; |
3488 | mdk_rdev_t *rdev; | |
3489 | ||
3490 | if (!in_chunk_boundary(mddev, raid_bio)) { | |
45b4233c | 3491 | pr_debug("chunk_aligned_read : non aligned\n"); |
f679623f RBJ |
3492 | return 0; |
3493 | } | |
3494 | /* | |
99c0fb5f | 3495 | * use bio_clone to make a copy of the bio |
f679623f RBJ |
3496 | */ |
3497 | align_bi = bio_clone(raid_bio, GFP_NOIO); | |
3498 | if (!align_bi) | |
3499 | return 0; | |
3500 | /* | |
3501 | * set bi_end_io to a new function, and set bi_private to the | |
3502 | * original bio. | |
3503 | */ | |
3504 | align_bi->bi_end_io = raid5_align_endio; | |
3505 | align_bi->bi_private = raid_bio; | |
3506 | /* | |
3507 | * compute position | |
3508 | */ | |
112bf897 N |
3509 | align_bi->bi_sector = raid5_compute_sector(conf, raid_bio->bi_sector, |
3510 | 0, | |
911d4ee8 | 3511 | &dd_idx, NULL); |
f679623f RBJ |
3512 | |
3513 | rcu_read_lock(); | |
3514 | rdev = rcu_dereference(conf->disks[dd_idx].rdev); | |
3515 | if (rdev && test_bit(In_sync, &rdev->flags)) { | |
f679623f RBJ |
3516 | atomic_inc(&rdev->nr_pending); |
3517 | rcu_read_unlock(); | |
46031f9a RBJ |
3518 | raid_bio->bi_next = (void*)rdev; |
3519 | align_bi->bi_bdev = rdev->bdev; | |
3520 | align_bi->bi_flags &= ~(1 << BIO_SEG_VALID); | |
3521 | align_bi->bi_sector += rdev->data_offset; | |
3522 | ||
387bb173 NB |
3523 | if (!bio_fits_rdev(align_bi)) { |
3524 | /* too big in some way */ | |
3525 | bio_put(align_bi); | |
3526 | rdev_dec_pending(rdev, mddev); | |
3527 | return 0; | |
3528 | } | |
3529 | ||
46031f9a RBJ |
3530 | spin_lock_irq(&conf->device_lock); |
3531 | wait_event_lock_irq(conf->wait_for_stripe, | |
3532 | conf->quiesce == 0, | |
3533 | conf->device_lock, /* nothing */); | |
3534 | atomic_inc(&conf->active_aligned_reads); | |
3535 | spin_unlock_irq(&conf->device_lock); | |
3536 | ||
f679623f RBJ |
3537 | generic_make_request(align_bi); |
3538 | return 1; | |
3539 | } else { | |
3540 | rcu_read_unlock(); | |
46031f9a | 3541 | bio_put(align_bi); |
f679623f RBJ |
3542 | return 0; |
3543 | } | |
3544 | } | |
3545 | ||
8b3e6cdc DW |
3546 | /* __get_priority_stripe - get the next stripe to process |
3547 | * | |
3548 | * Full stripe writes are allowed to pass preread active stripes up until | |
3549 | * the bypass_threshold is exceeded. In general the bypass_count | |
3550 | * increments when the handle_list is handled before the hold_list; however, it | |
3551 | * will not be incremented when STRIPE_IO_STARTED is sampled set signifying a | |
3552 | * stripe with in flight i/o. The bypass_count will be reset when the | |
3553 | * head of the hold_list has changed, i.e. the head was promoted to the | |
3554 | * handle_list. | |
3555 | */ | |
3556 | static struct stripe_head *__get_priority_stripe(raid5_conf_t *conf) | |
3557 | { | |
3558 | struct stripe_head *sh; | |
3559 | ||
3560 | pr_debug("%s: handle: %s hold: %s full_writes: %d bypass_count: %d\n", | |
3561 | __func__, | |
3562 | list_empty(&conf->handle_list) ? "empty" : "busy", | |
3563 | list_empty(&conf->hold_list) ? "empty" : "busy", | |
3564 | atomic_read(&conf->pending_full_writes), conf->bypass_count); | |
3565 | ||
3566 | if (!list_empty(&conf->handle_list)) { | |
3567 | sh = list_entry(conf->handle_list.next, typeof(*sh), lru); | |
3568 | ||
3569 | if (list_empty(&conf->hold_list)) | |
3570 | conf->bypass_count = 0; | |
3571 | else if (!test_bit(STRIPE_IO_STARTED, &sh->state)) { | |
3572 | if (conf->hold_list.next == conf->last_hold) | |
3573 | conf->bypass_count++; | |
3574 | else { | |
3575 | conf->last_hold = conf->hold_list.next; | |
3576 | conf->bypass_count -= conf->bypass_threshold; | |
3577 | if (conf->bypass_count < 0) | |
3578 | conf->bypass_count = 0; | |
3579 | } | |
3580 | } | |
3581 | } else if (!list_empty(&conf->hold_list) && | |
3582 | ((conf->bypass_threshold && | |
3583 | conf->bypass_count > conf->bypass_threshold) || | |
3584 | atomic_read(&conf->pending_full_writes) == 0)) { | |
3585 | sh = list_entry(conf->hold_list.next, | |
3586 | typeof(*sh), lru); | |
3587 | conf->bypass_count -= conf->bypass_threshold; | |
3588 | if (conf->bypass_count < 0) | |
3589 | conf->bypass_count = 0; | |
3590 | } else | |
3591 | return NULL; | |
3592 | ||
3593 | list_del_init(&sh->lru); | |
3594 | atomic_inc(&sh->count); | |
3595 | BUG_ON(atomic_read(&sh->count) != 1); | |
3596 | return sh; | |
3597 | } | |
f679623f | 3598 | |
165125e1 | 3599 | static int make_request(struct request_queue *q, struct bio * bi) |
1da177e4 LT |
3600 | { |
3601 | mddev_t *mddev = q->queuedata; | |
3602 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
911d4ee8 | 3603 | int dd_idx; |
1da177e4 LT |
3604 | sector_t new_sector; |
3605 | sector_t logical_sector, last_sector; | |
3606 | struct stripe_head *sh; | |
a362357b | 3607 | const int rw = bio_data_dir(bi); |
c9959059 | 3608 | int cpu, remaining; |
1da177e4 | 3609 | |
e5dcdd80 | 3610 | if (unlikely(bio_barrier(bi))) { |
6712ecf8 | 3611 | bio_endio(bi, -EOPNOTSUPP); |
e5dcdd80 N |
3612 | return 0; |
3613 | } | |
3614 | ||
3d310eb7 | 3615 | md_write_start(mddev, bi); |
06d91a5f | 3616 | |
074a7aca TH |
3617 | cpu = part_stat_lock(); |
3618 | part_stat_inc(cpu, &mddev->gendisk->part0, ios[rw]); | |
3619 | part_stat_add(cpu, &mddev->gendisk->part0, sectors[rw], | |
3620 | bio_sectors(bi)); | |
3621 | part_stat_unlock(); | |
1da177e4 | 3622 | |
802ba064 | 3623 | if (rw == READ && |
52488615 RBJ |
3624 | mddev->reshape_position == MaxSector && |
3625 | chunk_aligned_read(q,bi)) | |
99c0fb5f | 3626 | return 0; |
52488615 | 3627 | |
1da177e4 LT |
3628 | logical_sector = bi->bi_sector & ~((sector_t)STRIPE_SECTORS-1); |
3629 | last_sector = bi->bi_sector + (bi->bi_size>>9); | |
3630 | bi->bi_next = NULL; | |
3631 | bi->bi_phys_segments = 1; /* over-loaded to count active stripes */ | |
06d91a5f | 3632 | |
1da177e4 LT |
3633 | for (;logical_sector < last_sector; logical_sector += STRIPE_SECTORS) { |
3634 | DEFINE_WAIT(w); | |
16a53ecc | 3635 | int disks, data_disks; |
b5663ba4 | 3636 | int previous; |
b578d55f | 3637 | |
7ecaa1e6 | 3638 | retry: |
b5663ba4 | 3639 | previous = 0; |
b0f9ec04 | 3640 | disks = conf->raid_disks; |
b578d55f | 3641 | prepare_to_wait(&conf->wait_for_overlap, &w, TASK_UNINTERRUPTIBLE); |
b0f9ec04 | 3642 | if (unlikely(conf->reshape_progress != MaxSector)) { |
fef9c61f | 3643 | /* spinlock is needed as reshape_progress may be |
df8e7f76 N |
3644 | * 64bit on a 32bit platform, and so it might be |
3645 | * possible to see a half-updated value | |
fef9c61f | 3646 | * Ofcourse reshape_progress could change after |
df8e7f76 N |
3647 | * the lock is dropped, so once we get a reference |
3648 | * to the stripe that we think it is, we will have | |
3649 | * to check again. | |
3650 | */ | |
7ecaa1e6 | 3651 | spin_lock_irq(&conf->device_lock); |
fef9c61f N |
3652 | if (mddev->delta_disks < 0 |
3653 | ? logical_sector < conf->reshape_progress | |
3654 | : logical_sector >= conf->reshape_progress) { | |
7ecaa1e6 | 3655 | disks = conf->previous_raid_disks; |
b5663ba4 N |
3656 | previous = 1; |
3657 | } else { | |
fef9c61f N |
3658 | if (mddev->delta_disks < 0 |
3659 | ? logical_sector < conf->reshape_safe | |
3660 | : logical_sector >= conf->reshape_safe) { | |
b578d55f N |
3661 | spin_unlock_irq(&conf->device_lock); |
3662 | schedule(); | |
3663 | goto retry; | |
3664 | } | |
3665 | } | |
7ecaa1e6 N |
3666 | spin_unlock_irq(&conf->device_lock); |
3667 | } | |
16a53ecc N |
3668 | data_disks = disks - conf->max_degraded; |
3669 | ||
112bf897 N |
3670 | new_sector = raid5_compute_sector(conf, logical_sector, |
3671 | previous, | |
911d4ee8 | 3672 | &dd_idx, NULL); |
45b4233c | 3673 | pr_debug("raid5: make_request, sector %llu logical %llu\n", |
1da177e4 LT |
3674 | (unsigned long long)new_sector, |
3675 | (unsigned long long)logical_sector); | |
3676 | ||
b5663ba4 N |
3677 | sh = get_active_stripe(conf, new_sector, previous, |
3678 | (bi->bi_rw&RWA_MASK)); | |
1da177e4 | 3679 | if (sh) { |
b0f9ec04 | 3680 | if (unlikely(previous)) { |
7ecaa1e6 | 3681 | /* expansion might have moved on while waiting for a |
df8e7f76 N |
3682 | * stripe, so we must do the range check again. |
3683 | * Expansion could still move past after this | |
3684 | * test, but as we are holding a reference to | |
3685 | * 'sh', we know that if that happens, | |
3686 | * STRIPE_EXPANDING will get set and the expansion | |
3687 | * won't proceed until we finish with the stripe. | |
7ecaa1e6 N |
3688 | */ |
3689 | int must_retry = 0; | |
3690 | spin_lock_irq(&conf->device_lock); | |
b0f9ec04 N |
3691 | if (mddev->delta_disks < 0 |
3692 | ? logical_sector >= conf->reshape_progress | |
3693 | : logical_sector < conf->reshape_progress) | |
7ecaa1e6 N |
3694 | /* mismatch, need to try again */ |
3695 | must_retry = 1; | |
3696 | spin_unlock_irq(&conf->device_lock); | |
3697 | if (must_retry) { | |
3698 | release_stripe(sh); | |
3699 | goto retry; | |
3700 | } | |
3701 | } | |
e464eafd N |
3702 | /* FIXME what if we get a false positive because these |
3703 | * are being updated. | |
3704 | */ | |
3705 | if (logical_sector >= mddev->suspend_lo && | |
3706 | logical_sector < mddev->suspend_hi) { | |
3707 | release_stripe(sh); | |
3708 | schedule(); | |
3709 | goto retry; | |
3710 | } | |
7ecaa1e6 N |
3711 | |
3712 | if (test_bit(STRIPE_EXPANDING, &sh->state) || | |
3713 | !add_stripe_bio(sh, bi, dd_idx, (bi->bi_rw&RW_MASK))) { | |
3714 | /* Stripe is busy expanding or | |
3715 | * add failed due to overlap. Flush everything | |
1da177e4 LT |
3716 | * and wait a while |
3717 | */ | |
3718 | raid5_unplug_device(mddev->queue); | |
3719 | release_stripe(sh); | |
3720 | schedule(); | |
3721 | goto retry; | |
3722 | } | |
3723 | finish_wait(&conf->wait_for_overlap, &w); | |
6ed3003c N |
3724 | set_bit(STRIPE_HANDLE, &sh->state); |
3725 | clear_bit(STRIPE_DELAYED, &sh->state); | |
1da177e4 | 3726 | release_stripe(sh); |
1da177e4 LT |
3727 | } else { |
3728 | /* cannot get stripe for read-ahead, just give-up */ | |
3729 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
3730 | finish_wait(&conf->wait_for_overlap, &w); | |
3731 | break; | |
3732 | } | |
3733 | ||
3734 | } | |
3735 | spin_lock_irq(&conf->device_lock); | |
960e739d | 3736 | remaining = raid5_dec_bi_phys_segments(bi); |
f6344757 N |
3737 | spin_unlock_irq(&conf->device_lock); |
3738 | if (remaining == 0) { | |
1da177e4 | 3739 | |
16a53ecc | 3740 | if ( rw == WRITE ) |
1da177e4 | 3741 | md_write_end(mddev); |
6712ecf8 | 3742 | |
0e13fe23 | 3743 | bio_endio(bi, 0); |
1da177e4 | 3744 | } |
1da177e4 LT |
3745 | return 0; |
3746 | } | |
3747 | ||
b522adcd DW |
3748 | static sector_t raid5_size(mddev_t *mddev, sector_t sectors, int raid_disks); |
3749 | ||
52c03291 | 3750 | static sector_t reshape_request(mddev_t *mddev, sector_t sector_nr, int *skipped) |
1da177e4 | 3751 | { |
52c03291 N |
3752 | /* reshaping is quite different to recovery/resync so it is |
3753 | * handled quite separately ... here. | |
3754 | * | |
3755 | * On each call to sync_request, we gather one chunk worth of | |
3756 | * destination stripes and flag them as expanding. | |
3757 | * Then we find all the source stripes and request reads. | |
3758 | * As the reads complete, handle_stripe will copy the data | |
3759 | * into the destination stripe and release that stripe. | |
3760 | */ | |
1da177e4 LT |
3761 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; |
3762 | struct stripe_head *sh; | |
ccfcc3c1 | 3763 | sector_t first_sector, last_sector; |
f416885e N |
3764 | int raid_disks = conf->previous_raid_disks; |
3765 | int data_disks = raid_disks - conf->max_degraded; | |
3766 | int new_data_disks = conf->raid_disks - conf->max_degraded; | |
52c03291 N |
3767 | int i; |
3768 | int dd_idx; | |
c8f517c4 | 3769 | sector_t writepos, readpos, safepos; |
ec32a2bd | 3770 | sector_t stripe_addr; |
7a661381 | 3771 | int reshape_sectors; |
ab69ae12 | 3772 | struct list_head stripes; |
52c03291 | 3773 | |
fef9c61f N |
3774 | if (sector_nr == 0) { |
3775 | /* If restarting in the middle, skip the initial sectors */ | |
3776 | if (mddev->delta_disks < 0 && | |
3777 | conf->reshape_progress < raid5_size(mddev, 0, 0)) { | |
3778 | sector_nr = raid5_size(mddev, 0, 0) | |
3779 | - conf->reshape_progress; | |
3780 | } else if (mddev->delta_disks > 0 && | |
3781 | conf->reshape_progress > 0) | |
3782 | sector_nr = conf->reshape_progress; | |
f416885e | 3783 | sector_div(sector_nr, new_data_disks); |
fef9c61f N |
3784 | if (sector_nr) { |
3785 | *skipped = 1; | |
3786 | return sector_nr; | |
3787 | } | |
52c03291 N |
3788 | } |
3789 | ||
7a661381 N |
3790 | /* We need to process a full chunk at a time. |
3791 | * If old and new chunk sizes differ, we need to process the | |
3792 | * largest of these | |
3793 | */ | |
3794 | if (mddev->new_chunk > mddev->chunk_size) | |
3795 | reshape_sectors = mddev->new_chunk / 512; | |
3796 | else | |
3797 | reshape_sectors = mddev->chunk_size / 512; | |
3798 | ||
52c03291 N |
3799 | /* we update the metadata when there is more than 3Meg |
3800 | * in the block range (that is rather arbitrary, should | |
3801 | * probably be time based) or when the data about to be | |
3802 | * copied would over-write the source of the data at | |
3803 | * the front of the range. | |
fef9c61f N |
3804 | * i.e. one new_stripe along from reshape_progress new_maps |
3805 | * to after where reshape_safe old_maps to | |
52c03291 | 3806 | */ |
fef9c61f | 3807 | writepos = conf->reshape_progress; |
f416885e | 3808 | sector_div(writepos, new_data_disks); |
c8f517c4 N |
3809 | readpos = conf->reshape_progress; |
3810 | sector_div(readpos, data_disks); | |
fef9c61f | 3811 | safepos = conf->reshape_safe; |
f416885e | 3812 | sector_div(safepos, data_disks); |
fef9c61f | 3813 | if (mddev->delta_disks < 0) { |
7a661381 | 3814 | writepos -= reshape_sectors; |
c8f517c4 | 3815 | readpos += reshape_sectors; |
7a661381 | 3816 | safepos += reshape_sectors; |
fef9c61f | 3817 | } else { |
7a661381 | 3818 | writepos += reshape_sectors; |
c8f517c4 | 3819 | readpos -= reshape_sectors; |
7a661381 | 3820 | safepos -= reshape_sectors; |
fef9c61f | 3821 | } |
52c03291 | 3822 | |
c8f517c4 N |
3823 | /* 'writepos' is the most advanced device address we might write. |
3824 | * 'readpos' is the least advanced device address we might read. | |
3825 | * 'safepos' is the least address recorded in the metadata as having | |
3826 | * been reshaped. | |
3827 | * If 'readpos' is behind 'writepos', then there is no way that we can | |
3828 | * ensure safety in the face of a crash - that must be done by userspace | |
3829 | * making a backup of the data. So in that case there is no particular | |
3830 | * rush to update metadata. | |
3831 | * Otherwise if 'safepos' is behind 'writepos', then we really need to | |
3832 | * update the metadata to advance 'safepos' to match 'readpos' so that | |
3833 | * we can be safe in the event of a crash. | |
3834 | * So we insist on updating metadata if safepos is behind writepos and | |
3835 | * readpos is beyond writepos. | |
3836 | * In any case, update the metadata every 10 seconds. | |
3837 | * Maybe that number should be configurable, but I'm not sure it is | |
3838 | * worth it.... maybe it could be a multiple of safemode_delay??? | |
3839 | */ | |
fef9c61f | 3840 | if ((mddev->delta_disks < 0 |
c8f517c4 N |
3841 | ? (safepos > writepos && readpos < writepos) |
3842 | : (safepos < writepos && readpos > writepos)) || | |
3843 | time_after(jiffies, conf->reshape_checkpoint + 10*HZ)) { | |
52c03291 N |
3844 | /* Cannot proceed until we've updated the superblock... */ |
3845 | wait_event(conf->wait_for_overlap, | |
3846 | atomic_read(&conf->reshape_stripes)==0); | |
fef9c61f | 3847 | mddev->reshape_position = conf->reshape_progress; |
c8f517c4 | 3848 | conf->reshape_checkpoint = jiffies; |
850b2b42 | 3849 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
52c03291 | 3850 | md_wakeup_thread(mddev->thread); |
850b2b42 | 3851 | wait_event(mddev->sb_wait, mddev->flags == 0 || |
52c03291 N |
3852 | kthread_should_stop()); |
3853 | spin_lock_irq(&conf->device_lock); | |
fef9c61f | 3854 | conf->reshape_safe = mddev->reshape_position; |
52c03291 N |
3855 | spin_unlock_irq(&conf->device_lock); |
3856 | wake_up(&conf->wait_for_overlap); | |
3857 | } | |
3858 | ||
ec32a2bd N |
3859 | if (mddev->delta_disks < 0) { |
3860 | BUG_ON(conf->reshape_progress == 0); | |
3861 | stripe_addr = writepos; | |
3862 | BUG_ON((mddev->dev_sectors & | |
7a661381 N |
3863 | ~((sector_t)reshape_sectors - 1)) |
3864 | - reshape_sectors - stripe_addr | |
ec32a2bd N |
3865 | != sector_nr); |
3866 | } else { | |
7a661381 | 3867 | BUG_ON(writepos != sector_nr + reshape_sectors); |
ec32a2bd N |
3868 | stripe_addr = sector_nr; |
3869 | } | |
ab69ae12 | 3870 | INIT_LIST_HEAD(&stripes); |
7a661381 | 3871 | for (i = 0; i < reshape_sectors; i += STRIPE_SECTORS) { |
52c03291 N |
3872 | int j; |
3873 | int skipped = 0; | |
ec32a2bd | 3874 | sh = get_active_stripe(conf, stripe_addr+i, 0, 0); |
52c03291 N |
3875 | set_bit(STRIPE_EXPANDING, &sh->state); |
3876 | atomic_inc(&conf->reshape_stripes); | |
3877 | /* If any of this stripe is beyond the end of the old | |
3878 | * array, then we need to zero those blocks | |
3879 | */ | |
3880 | for (j=sh->disks; j--;) { | |
3881 | sector_t s; | |
3882 | if (j == sh->pd_idx) | |
3883 | continue; | |
f416885e | 3884 | if (conf->level == 6 && |
d0dabf7e | 3885 | j == sh->qd_idx) |
f416885e | 3886 | continue; |
784052ec | 3887 | s = compute_blocknr(sh, j, 0); |
b522adcd | 3888 | if (s < raid5_size(mddev, 0, 0)) { |
52c03291 N |
3889 | skipped = 1; |
3890 | continue; | |
3891 | } | |
3892 | memset(page_address(sh->dev[j].page), 0, STRIPE_SIZE); | |
3893 | set_bit(R5_Expanded, &sh->dev[j].flags); | |
3894 | set_bit(R5_UPTODATE, &sh->dev[j].flags); | |
3895 | } | |
3896 | if (!skipped) { | |
3897 | set_bit(STRIPE_EXPAND_READY, &sh->state); | |
3898 | set_bit(STRIPE_HANDLE, &sh->state); | |
3899 | } | |
ab69ae12 | 3900 | list_add(&sh->lru, &stripes); |
52c03291 N |
3901 | } |
3902 | spin_lock_irq(&conf->device_lock); | |
fef9c61f | 3903 | if (mddev->delta_disks < 0) |
7a661381 | 3904 | conf->reshape_progress -= reshape_sectors * new_data_disks; |
fef9c61f | 3905 | else |
7a661381 | 3906 | conf->reshape_progress += reshape_sectors * new_data_disks; |
52c03291 N |
3907 | spin_unlock_irq(&conf->device_lock); |
3908 | /* Ok, those stripe are ready. We can start scheduling | |
3909 | * reads on the source stripes. | |
3910 | * The source stripes are determined by mapping the first and last | |
3911 | * block on the destination stripes. | |
3912 | */ | |
52c03291 | 3913 | first_sector = |
ec32a2bd | 3914 | raid5_compute_sector(conf, stripe_addr*(new_data_disks), |
911d4ee8 | 3915 | 1, &dd_idx, NULL); |
52c03291 | 3916 | last_sector = |
ec32a2bd | 3917 | raid5_compute_sector(conf, ((stripe_addr+conf->chunk_size/512) |
112bf897 | 3918 | *(new_data_disks) - 1), |
911d4ee8 | 3919 | 1, &dd_idx, NULL); |
58c0fed4 AN |
3920 | if (last_sector >= mddev->dev_sectors) |
3921 | last_sector = mddev->dev_sectors - 1; | |
52c03291 | 3922 | while (first_sector <= last_sector) { |
b5663ba4 | 3923 | sh = get_active_stripe(conf, first_sector, 1, 0); |
52c03291 N |
3924 | set_bit(STRIPE_EXPAND_SOURCE, &sh->state); |
3925 | set_bit(STRIPE_HANDLE, &sh->state); | |
3926 | release_stripe(sh); | |
3927 | first_sector += STRIPE_SECTORS; | |
3928 | } | |
ab69ae12 N |
3929 | /* Now that the sources are clearly marked, we can release |
3930 | * the destination stripes | |
3931 | */ | |
3932 | while (!list_empty(&stripes)) { | |
3933 | sh = list_entry(stripes.next, struct stripe_head, lru); | |
3934 | list_del_init(&sh->lru); | |
3935 | release_stripe(sh); | |
3936 | } | |
c6207277 N |
3937 | /* If this takes us to the resync_max point where we have to pause, |
3938 | * then we need to write out the superblock. | |
3939 | */ | |
7a661381 | 3940 | sector_nr += reshape_sectors; |
c6207277 N |
3941 | if (sector_nr >= mddev->resync_max) { |
3942 | /* Cannot proceed until we've updated the superblock... */ | |
3943 | wait_event(conf->wait_for_overlap, | |
3944 | atomic_read(&conf->reshape_stripes) == 0); | |
fef9c61f | 3945 | mddev->reshape_position = conf->reshape_progress; |
c8f517c4 | 3946 | conf->reshape_checkpoint = jiffies; |
c6207277 N |
3947 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
3948 | md_wakeup_thread(mddev->thread); | |
3949 | wait_event(mddev->sb_wait, | |
3950 | !test_bit(MD_CHANGE_DEVS, &mddev->flags) | |
3951 | || kthread_should_stop()); | |
3952 | spin_lock_irq(&conf->device_lock); | |
fef9c61f | 3953 | conf->reshape_safe = mddev->reshape_position; |
c6207277 N |
3954 | spin_unlock_irq(&conf->device_lock); |
3955 | wake_up(&conf->wait_for_overlap); | |
3956 | } | |
7a661381 | 3957 | return reshape_sectors; |
52c03291 N |
3958 | } |
3959 | ||
3960 | /* FIXME go_faster isn't used */ | |
3961 | static inline sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, int go_faster) | |
3962 | { | |
3963 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; | |
3964 | struct stripe_head *sh; | |
58c0fed4 | 3965 | sector_t max_sector = mddev->dev_sectors; |
72626685 | 3966 | int sync_blocks; |
16a53ecc N |
3967 | int still_degraded = 0; |
3968 | int i; | |
1da177e4 | 3969 | |
72626685 | 3970 | if (sector_nr >= max_sector) { |
1da177e4 LT |
3971 | /* just being told to finish up .. nothing much to do */ |
3972 | unplug_slaves(mddev); | |
cea9c228 | 3973 | |
29269553 N |
3974 | if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) { |
3975 | end_reshape(conf); | |
3976 | return 0; | |
3977 | } | |
72626685 N |
3978 | |
3979 | if (mddev->curr_resync < max_sector) /* aborted */ | |
3980 | bitmap_end_sync(mddev->bitmap, mddev->curr_resync, | |
3981 | &sync_blocks, 1); | |
16a53ecc | 3982 | else /* completed sync */ |
72626685 N |
3983 | conf->fullsync = 0; |
3984 | bitmap_close_sync(mddev->bitmap); | |
3985 | ||
1da177e4 LT |
3986 | return 0; |
3987 | } | |
ccfcc3c1 | 3988 | |
52c03291 N |
3989 | if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) |
3990 | return reshape_request(mddev, sector_nr, skipped); | |
f6705578 | 3991 | |
c6207277 N |
3992 | /* No need to check resync_max as we never do more than one |
3993 | * stripe, and as resync_max will always be on a chunk boundary, | |
3994 | * if the check in md_do_sync didn't fire, there is no chance | |
3995 | * of overstepping resync_max here | |
3996 | */ | |
3997 | ||
16a53ecc | 3998 | /* if there is too many failed drives and we are trying |
1da177e4 LT |
3999 | * to resync, then assert that we are finished, because there is |
4000 | * nothing we can do. | |
4001 | */ | |
3285edf1 | 4002 | if (mddev->degraded >= conf->max_degraded && |
16a53ecc | 4003 | test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) { |
58c0fed4 | 4004 | sector_t rv = mddev->dev_sectors - sector_nr; |
57afd89f | 4005 | *skipped = 1; |
1da177e4 LT |
4006 | return rv; |
4007 | } | |
72626685 | 4008 | if (!bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, 1) && |
3855ad9f | 4009 | !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) && |
72626685 N |
4010 | !conf->fullsync && sync_blocks >= STRIPE_SECTORS) { |
4011 | /* we can skip this block, and probably more */ | |
4012 | sync_blocks /= STRIPE_SECTORS; | |
4013 | *skipped = 1; | |
4014 | return sync_blocks * STRIPE_SECTORS; /* keep things rounded to whole stripes */ | |
4015 | } | |
1da177e4 | 4016 | |
b47490c9 N |
4017 | |
4018 | bitmap_cond_end_sync(mddev->bitmap, sector_nr); | |
4019 | ||
b5663ba4 | 4020 | sh = get_active_stripe(conf, sector_nr, 0, 1); |
1da177e4 | 4021 | if (sh == NULL) { |
b5663ba4 | 4022 | sh = get_active_stripe(conf, sector_nr, 0, 0); |
1da177e4 | 4023 | /* make sure we don't swamp the stripe cache if someone else |
16a53ecc | 4024 | * is trying to get access |
1da177e4 | 4025 | */ |
66c006a5 | 4026 | schedule_timeout_uninterruptible(1); |
1da177e4 | 4027 | } |
16a53ecc N |
4028 | /* Need to check if array will still be degraded after recovery/resync |
4029 | * We don't need to check the 'failed' flag as when that gets set, | |
4030 | * recovery aborts. | |
4031 | */ | |
4032 | for (i=0; i<mddev->raid_disks; i++) | |
4033 | if (conf->disks[i].rdev == NULL) | |
4034 | still_degraded = 1; | |
4035 | ||
4036 | bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, still_degraded); | |
4037 | ||
4038 | spin_lock(&sh->lock); | |
1da177e4 LT |
4039 | set_bit(STRIPE_SYNCING, &sh->state); |
4040 | clear_bit(STRIPE_INSYNC, &sh->state); | |
4041 | spin_unlock(&sh->lock); | |
4042 | ||
df10cfbc DW |
4043 | /* wait for any blocked device to be handled */ |
4044 | while(unlikely(!handle_stripe(sh, NULL))) | |
4045 | ; | |
1da177e4 LT |
4046 | release_stripe(sh); |
4047 | ||
4048 | return STRIPE_SECTORS; | |
4049 | } | |
4050 | ||
46031f9a RBJ |
4051 | static int retry_aligned_read(raid5_conf_t *conf, struct bio *raid_bio) |
4052 | { | |
4053 | /* We may not be able to submit a whole bio at once as there | |
4054 | * may not be enough stripe_heads available. | |
4055 | * We cannot pre-allocate enough stripe_heads as we may need | |
4056 | * more than exist in the cache (if we allow ever large chunks). | |
4057 | * So we do one stripe head at a time and record in | |
4058 | * ->bi_hw_segments how many have been done. | |
4059 | * | |
4060 | * We *know* that this entire raid_bio is in one chunk, so | |
4061 | * it will be only one 'dd_idx' and only need one call to raid5_compute_sector. | |
4062 | */ | |
4063 | struct stripe_head *sh; | |
911d4ee8 | 4064 | int dd_idx; |
46031f9a RBJ |
4065 | sector_t sector, logical_sector, last_sector; |
4066 | int scnt = 0; | |
4067 | int remaining; | |
4068 | int handled = 0; | |
4069 | ||
4070 | logical_sector = raid_bio->bi_sector & ~((sector_t)STRIPE_SECTORS-1); | |
112bf897 | 4071 | sector = raid5_compute_sector(conf, logical_sector, |
911d4ee8 | 4072 | 0, &dd_idx, NULL); |
46031f9a RBJ |
4073 | last_sector = raid_bio->bi_sector + (raid_bio->bi_size>>9); |
4074 | ||
4075 | for (; logical_sector < last_sector; | |
387bb173 NB |
4076 | logical_sector += STRIPE_SECTORS, |
4077 | sector += STRIPE_SECTORS, | |
4078 | scnt++) { | |
46031f9a | 4079 | |
960e739d | 4080 | if (scnt < raid5_bi_hw_segments(raid_bio)) |
46031f9a RBJ |
4081 | /* already done this stripe */ |
4082 | continue; | |
4083 | ||
b5663ba4 | 4084 | sh = get_active_stripe(conf, sector, 0, 1); |
46031f9a RBJ |
4085 | |
4086 | if (!sh) { | |
4087 | /* failed to get a stripe - must wait */ | |
960e739d | 4088 | raid5_set_bi_hw_segments(raid_bio, scnt); |
46031f9a RBJ |
4089 | conf->retry_read_aligned = raid_bio; |
4090 | return handled; | |
4091 | } | |
4092 | ||
4093 | set_bit(R5_ReadError, &sh->dev[dd_idx].flags); | |
387bb173 NB |
4094 | if (!add_stripe_bio(sh, raid_bio, dd_idx, 0)) { |
4095 | release_stripe(sh); | |
960e739d | 4096 | raid5_set_bi_hw_segments(raid_bio, scnt); |
387bb173 NB |
4097 | conf->retry_read_aligned = raid_bio; |
4098 | return handled; | |
4099 | } | |
4100 | ||
46031f9a RBJ |
4101 | handle_stripe(sh, NULL); |
4102 | release_stripe(sh); | |
4103 | handled++; | |
4104 | } | |
4105 | spin_lock_irq(&conf->device_lock); | |
960e739d | 4106 | remaining = raid5_dec_bi_phys_segments(raid_bio); |
46031f9a | 4107 | spin_unlock_irq(&conf->device_lock); |
0e13fe23 NB |
4108 | if (remaining == 0) |
4109 | bio_endio(raid_bio, 0); | |
46031f9a RBJ |
4110 | if (atomic_dec_and_test(&conf->active_aligned_reads)) |
4111 | wake_up(&conf->wait_for_stripe); | |
4112 | return handled; | |
4113 | } | |
4114 | ||
4115 | ||
4116 | ||
1da177e4 LT |
4117 | /* |
4118 | * This is our raid5 kernel thread. | |
4119 | * | |
4120 | * We scan the hash table for stripes which can be handled now. | |
4121 | * During the scan, completed stripes are saved for us by the interrupt | |
4122 | * handler, so that they will not have to wait for our next wakeup. | |
4123 | */ | |
6ed3003c | 4124 | static void raid5d(mddev_t *mddev) |
1da177e4 LT |
4125 | { |
4126 | struct stripe_head *sh; | |
4127 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4128 | int handled; | |
4129 | ||
45b4233c | 4130 | pr_debug("+++ raid5d active\n"); |
1da177e4 LT |
4131 | |
4132 | md_check_recovery(mddev); | |
1da177e4 LT |
4133 | |
4134 | handled = 0; | |
4135 | spin_lock_irq(&conf->device_lock); | |
4136 | while (1) { | |
46031f9a | 4137 | struct bio *bio; |
1da177e4 | 4138 | |
ae3c20cc | 4139 | if (conf->seq_flush != conf->seq_write) { |
72626685 | 4140 | int seq = conf->seq_flush; |
700e432d | 4141 | spin_unlock_irq(&conf->device_lock); |
72626685 | 4142 | bitmap_unplug(mddev->bitmap); |
700e432d | 4143 | spin_lock_irq(&conf->device_lock); |
72626685 N |
4144 | conf->seq_write = seq; |
4145 | activate_bit_delay(conf); | |
4146 | } | |
4147 | ||
46031f9a RBJ |
4148 | while ((bio = remove_bio_from_retry(conf))) { |
4149 | int ok; | |
4150 | spin_unlock_irq(&conf->device_lock); | |
4151 | ok = retry_aligned_read(conf, bio); | |
4152 | spin_lock_irq(&conf->device_lock); | |
4153 | if (!ok) | |
4154 | break; | |
4155 | handled++; | |
4156 | } | |
4157 | ||
8b3e6cdc DW |
4158 | sh = __get_priority_stripe(conf); |
4159 | ||
c9f21aaf | 4160 | if (!sh) |
1da177e4 | 4161 | break; |
1da177e4 LT |
4162 | spin_unlock_irq(&conf->device_lock); |
4163 | ||
4164 | handled++; | |
16a53ecc | 4165 | handle_stripe(sh, conf->spare_page); |
1da177e4 LT |
4166 | release_stripe(sh); |
4167 | ||
4168 | spin_lock_irq(&conf->device_lock); | |
4169 | } | |
45b4233c | 4170 | pr_debug("%d stripes handled\n", handled); |
1da177e4 LT |
4171 | |
4172 | spin_unlock_irq(&conf->device_lock); | |
4173 | ||
c9f21aaf | 4174 | async_tx_issue_pending_all(); |
1da177e4 LT |
4175 | unplug_slaves(mddev); |
4176 | ||
45b4233c | 4177 | pr_debug("--- raid5d inactive\n"); |
1da177e4 LT |
4178 | } |
4179 | ||
3f294f4f | 4180 | static ssize_t |
007583c9 | 4181 | raid5_show_stripe_cache_size(mddev_t *mddev, char *page) |
3f294f4f | 4182 | { |
007583c9 | 4183 | raid5_conf_t *conf = mddev_to_conf(mddev); |
96de1e66 N |
4184 | if (conf) |
4185 | return sprintf(page, "%d\n", conf->max_nr_stripes); | |
4186 | else | |
4187 | return 0; | |
3f294f4f N |
4188 | } |
4189 | ||
4190 | static ssize_t | |
007583c9 | 4191 | raid5_store_stripe_cache_size(mddev_t *mddev, const char *page, size_t len) |
3f294f4f | 4192 | { |
007583c9 | 4193 | raid5_conf_t *conf = mddev_to_conf(mddev); |
4ef197d8 | 4194 | unsigned long new; |
b5470dc5 DW |
4195 | int err; |
4196 | ||
3f294f4f N |
4197 | if (len >= PAGE_SIZE) |
4198 | return -EINVAL; | |
96de1e66 N |
4199 | if (!conf) |
4200 | return -ENODEV; | |
3f294f4f | 4201 | |
4ef197d8 | 4202 | if (strict_strtoul(page, 10, &new)) |
3f294f4f N |
4203 | return -EINVAL; |
4204 | if (new <= 16 || new > 32768) | |
4205 | return -EINVAL; | |
4206 | while (new < conf->max_nr_stripes) { | |
4207 | if (drop_one_stripe(conf)) | |
4208 | conf->max_nr_stripes--; | |
4209 | else | |
4210 | break; | |
4211 | } | |
b5470dc5 DW |
4212 | err = md_allow_write(mddev); |
4213 | if (err) | |
4214 | return err; | |
3f294f4f N |
4215 | while (new > conf->max_nr_stripes) { |
4216 | if (grow_one_stripe(conf)) | |
4217 | conf->max_nr_stripes++; | |
4218 | else break; | |
4219 | } | |
4220 | return len; | |
4221 | } | |
007583c9 | 4222 | |
96de1e66 N |
4223 | static struct md_sysfs_entry |
4224 | raid5_stripecache_size = __ATTR(stripe_cache_size, S_IRUGO | S_IWUSR, | |
4225 | raid5_show_stripe_cache_size, | |
4226 | raid5_store_stripe_cache_size); | |
3f294f4f | 4227 | |
8b3e6cdc DW |
4228 | static ssize_t |
4229 | raid5_show_preread_threshold(mddev_t *mddev, char *page) | |
4230 | { | |
4231 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4232 | if (conf) | |
4233 | return sprintf(page, "%d\n", conf->bypass_threshold); | |
4234 | else | |
4235 | return 0; | |
4236 | } | |
4237 | ||
4238 | static ssize_t | |
4239 | raid5_store_preread_threshold(mddev_t *mddev, const char *page, size_t len) | |
4240 | { | |
4241 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4ef197d8 | 4242 | unsigned long new; |
8b3e6cdc DW |
4243 | if (len >= PAGE_SIZE) |
4244 | return -EINVAL; | |
4245 | if (!conf) | |
4246 | return -ENODEV; | |
4247 | ||
4ef197d8 | 4248 | if (strict_strtoul(page, 10, &new)) |
8b3e6cdc | 4249 | return -EINVAL; |
4ef197d8 | 4250 | if (new > conf->max_nr_stripes) |
8b3e6cdc DW |
4251 | return -EINVAL; |
4252 | conf->bypass_threshold = new; | |
4253 | return len; | |
4254 | } | |
4255 | ||
4256 | static struct md_sysfs_entry | |
4257 | raid5_preread_bypass_threshold = __ATTR(preread_bypass_threshold, | |
4258 | S_IRUGO | S_IWUSR, | |
4259 | raid5_show_preread_threshold, | |
4260 | raid5_store_preread_threshold); | |
4261 | ||
3f294f4f | 4262 | static ssize_t |
96de1e66 | 4263 | stripe_cache_active_show(mddev_t *mddev, char *page) |
3f294f4f | 4264 | { |
007583c9 | 4265 | raid5_conf_t *conf = mddev_to_conf(mddev); |
96de1e66 N |
4266 | if (conf) |
4267 | return sprintf(page, "%d\n", atomic_read(&conf->active_stripes)); | |
4268 | else | |
4269 | return 0; | |
3f294f4f N |
4270 | } |
4271 | ||
96de1e66 N |
4272 | static struct md_sysfs_entry |
4273 | raid5_stripecache_active = __ATTR_RO(stripe_cache_active); | |
3f294f4f | 4274 | |
007583c9 | 4275 | static struct attribute *raid5_attrs[] = { |
3f294f4f N |
4276 | &raid5_stripecache_size.attr, |
4277 | &raid5_stripecache_active.attr, | |
8b3e6cdc | 4278 | &raid5_preread_bypass_threshold.attr, |
3f294f4f N |
4279 | NULL, |
4280 | }; | |
007583c9 N |
4281 | static struct attribute_group raid5_attrs_group = { |
4282 | .name = NULL, | |
4283 | .attrs = raid5_attrs, | |
3f294f4f N |
4284 | }; |
4285 | ||
80c3a6ce DW |
4286 | static sector_t |
4287 | raid5_size(mddev_t *mddev, sector_t sectors, int raid_disks) | |
4288 | { | |
4289 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4290 | ||
4291 | if (!sectors) | |
4292 | sectors = mddev->dev_sectors; | |
7ec05478 N |
4293 | if (!raid_disks) { |
4294 | /* size is defined by the smallest of previous and new size */ | |
4295 | if (conf->raid_disks < conf->previous_raid_disks) | |
4296 | raid_disks = conf->raid_disks; | |
4297 | else | |
4298 | raid_disks = conf->previous_raid_disks; | |
4299 | } | |
80c3a6ce DW |
4300 | |
4301 | sectors &= ~((sector_t)mddev->chunk_size/512 - 1); | |
784052ec | 4302 | sectors &= ~((sector_t)mddev->new_chunk/512 - 1); |
80c3a6ce DW |
4303 | return sectors * (raid_disks - conf->max_degraded); |
4304 | } | |
4305 | ||
91adb564 | 4306 | static raid5_conf_t *setup_conf(mddev_t *mddev) |
1da177e4 LT |
4307 | { |
4308 | raid5_conf_t *conf; | |
4309 | int raid_disk, memory; | |
4310 | mdk_rdev_t *rdev; | |
4311 | struct disk_info *disk; | |
1da177e4 | 4312 | |
91adb564 N |
4313 | if (mddev->new_level != 5 |
4314 | && mddev->new_level != 4 | |
4315 | && mddev->new_level != 6) { | |
16a53ecc | 4316 | printk(KERN_ERR "raid5: %s: raid level not set to 4/5/6 (%d)\n", |
91adb564 N |
4317 | mdname(mddev), mddev->new_level); |
4318 | return ERR_PTR(-EIO); | |
1da177e4 | 4319 | } |
91adb564 N |
4320 | if ((mddev->new_level == 5 |
4321 | && !algorithm_valid_raid5(mddev->new_layout)) || | |
4322 | (mddev->new_level == 6 | |
4323 | && !algorithm_valid_raid6(mddev->new_layout))) { | |
99c0fb5f | 4324 | printk(KERN_ERR "raid5: %s: layout %d not supported\n", |
91adb564 N |
4325 | mdname(mddev), mddev->new_layout); |
4326 | return ERR_PTR(-EIO); | |
99c0fb5f | 4327 | } |
91adb564 N |
4328 | if (mddev->new_level == 6 && mddev->raid_disks < 4) { |
4329 | printk(KERN_ERR "raid6: not enough configured devices for %s (%d, minimum 4)\n", | |
4330 | mdname(mddev), mddev->raid_disks); | |
4331 | return ERR_PTR(-EINVAL); | |
4bbf3771 N |
4332 | } |
4333 | ||
91adb564 N |
4334 | if (!mddev->new_chunk || mddev->new_chunk % PAGE_SIZE) { |
4335 | printk(KERN_ERR "raid5: invalid chunk size %d for %s\n", | |
4336 | mddev->new_chunk, mdname(mddev)); | |
4337 | return ERR_PTR(-EINVAL); | |
f6705578 N |
4338 | } |
4339 | ||
91adb564 N |
4340 | conf = kzalloc(sizeof(raid5_conf_t), GFP_KERNEL); |
4341 | if (conf == NULL) | |
1da177e4 | 4342 | goto abort; |
91adb564 N |
4343 | |
4344 | conf->raid_disks = mddev->raid_disks; | |
4345 | if (mddev->reshape_position == MaxSector) | |
4346 | conf->previous_raid_disks = mddev->raid_disks; | |
4347 | else | |
f6705578 | 4348 | conf->previous_raid_disks = mddev->raid_disks - mddev->delta_disks; |
f6705578 N |
4349 | |
4350 | conf->disks = kzalloc(conf->raid_disks * sizeof(struct disk_info), | |
b55e6bfc N |
4351 | GFP_KERNEL); |
4352 | if (!conf->disks) | |
4353 | goto abort; | |
9ffae0cf | 4354 | |
1da177e4 LT |
4355 | conf->mddev = mddev; |
4356 | ||
fccddba0 | 4357 | if ((conf->stripe_hashtbl = kzalloc(PAGE_SIZE, GFP_KERNEL)) == NULL) |
1da177e4 | 4358 | goto abort; |
1da177e4 | 4359 | |
91adb564 | 4360 | if (mddev->new_level == 6) { |
16a53ecc N |
4361 | conf->spare_page = alloc_page(GFP_KERNEL); |
4362 | if (!conf->spare_page) | |
4363 | goto abort; | |
4364 | } | |
1da177e4 LT |
4365 | spin_lock_init(&conf->device_lock); |
4366 | init_waitqueue_head(&conf->wait_for_stripe); | |
4367 | init_waitqueue_head(&conf->wait_for_overlap); | |
4368 | INIT_LIST_HEAD(&conf->handle_list); | |
8b3e6cdc | 4369 | INIT_LIST_HEAD(&conf->hold_list); |
1da177e4 | 4370 | INIT_LIST_HEAD(&conf->delayed_list); |
72626685 | 4371 | INIT_LIST_HEAD(&conf->bitmap_list); |
1da177e4 LT |
4372 | INIT_LIST_HEAD(&conf->inactive_list); |
4373 | atomic_set(&conf->active_stripes, 0); | |
4374 | atomic_set(&conf->preread_active_stripes, 0); | |
46031f9a | 4375 | atomic_set(&conf->active_aligned_reads, 0); |
8b3e6cdc | 4376 | conf->bypass_threshold = BYPASS_THRESHOLD; |
1da177e4 | 4377 | |
45b4233c | 4378 | pr_debug("raid5: run(%s) called.\n", mdname(mddev)); |
1da177e4 | 4379 | |
159ec1fc | 4380 | list_for_each_entry(rdev, &mddev->disks, same_set) { |
1da177e4 | 4381 | raid_disk = rdev->raid_disk; |
f6705578 | 4382 | if (raid_disk >= conf->raid_disks |
1da177e4 LT |
4383 | || raid_disk < 0) |
4384 | continue; | |
4385 | disk = conf->disks + raid_disk; | |
4386 | ||
4387 | disk->rdev = rdev; | |
4388 | ||
b2d444d7 | 4389 | if (test_bit(In_sync, &rdev->flags)) { |
1da177e4 LT |
4390 | char b[BDEVNAME_SIZE]; |
4391 | printk(KERN_INFO "raid5: device %s operational as raid" | |
4392 | " disk %d\n", bdevname(rdev->bdev,b), | |
4393 | raid_disk); | |
8c2e870a NB |
4394 | } else |
4395 | /* Cannot rely on bitmap to complete recovery */ | |
4396 | conf->fullsync = 1; | |
1da177e4 LT |
4397 | } |
4398 | ||
91adb564 N |
4399 | conf->chunk_size = mddev->new_chunk; |
4400 | conf->level = mddev->new_level; | |
16a53ecc N |
4401 | if (conf->level == 6) |
4402 | conf->max_degraded = 2; | |
4403 | else | |
4404 | conf->max_degraded = 1; | |
91adb564 | 4405 | conf->algorithm = mddev->new_layout; |
1da177e4 | 4406 | conf->max_nr_stripes = NR_STRIPES; |
fef9c61f | 4407 | conf->reshape_progress = mddev->reshape_position; |
e183eaed | 4408 | if (conf->reshape_progress != MaxSector) { |
784052ec | 4409 | conf->prev_chunk = mddev->chunk_size; |
e183eaed N |
4410 | conf->prev_algo = mddev->layout; |
4411 | } | |
1da177e4 | 4412 | |
91adb564 N |
4413 | memory = conf->max_nr_stripes * (sizeof(struct stripe_head) + |
4414 | conf->raid_disks * ((sizeof(struct bio) + PAGE_SIZE))) / 1024; | |
4415 | if (grow_stripes(conf, conf->max_nr_stripes)) { | |
4416 | printk(KERN_ERR | |
4417 | "raid5: couldn't allocate %dkB for buffers\n", memory); | |
4418 | goto abort; | |
4419 | } else | |
4420 | printk(KERN_INFO "raid5: allocated %dkB for %s\n", | |
4421 | memory, mdname(mddev)); | |
1da177e4 | 4422 | |
91adb564 N |
4423 | conf->thread = md_register_thread(raid5d, mddev, "%s_raid5"); |
4424 | if (!conf->thread) { | |
4425 | printk(KERN_ERR | |
4426 | "raid5: couldn't allocate thread for %s\n", | |
4427 | mdname(mddev)); | |
16a53ecc N |
4428 | goto abort; |
4429 | } | |
91adb564 N |
4430 | |
4431 | return conf; | |
4432 | ||
4433 | abort: | |
4434 | if (conf) { | |
4435 | shrink_stripes(conf); | |
4436 | safe_put_page(conf->spare_page); | |
4437 | kfree(conf->disks); | |
4438 | kfree(conf->stripe_hashtbl); | |
4439 | kfree(conf); | |
4440 | return ERR_PTR(-EIO); | |
4441 | } else | |
4442 | return ERR_PTR(-ENOMEM); | |
4443 | } | |
4444 | ||
4445 | static int run(mddev_t *mddev) | |
4446 | { | |
4447 | raid5_conf_t *conf; | |
4448 | int working_disks = 0; | |
4449 | mdk_rdev_t *rdev; | |
4450 | ||
4451 | if (mddev->reshape_position != MaxSector) { | |
4452 | /* Check that we can continue the reshape. | |
4453 | * Currently only disks can change, it must | |
4454 | * increase, and we must be past the point where | |
4455 | * a stripe over-writes itself | |
4456 | */ | |
4457 | sector_t here_new, here_old; | |
4458 | int old_disks; | |
18b00334 | 4459 | int max_degraded = (mddev->level == 6 ? 2 : 1); |
91adb564 | 4460 | |
88ce4930 | 4461 | if (mddev->new_level != mddev->level) { |
91adb564 N |
4462 | printk(KERN_ERR "raid5: %s: unsupported reshape " |
4463 | "required - aborting.\n", | |
4464 | mdname(mddev)); | |
4465 | return -EINVAL; | |
4466 | } | |
91adb564 N |
4467 | old_disks = mddev->raid_disks - mddev->delta_disks; |
4468 | /* reshape_position must be on a new-stripe boundary, and one | |
4469 | * further up in new geometry must map after here in old | |
4470 | * geometry. | |
4471 | */ | |
4472 | here_new = mddev->reshape_position; | |
784052ec | 4473 | if (sector_div(here_new, (mddev->new_chunk>>9)* |
91adb564 N |
4474 | (mddev->raid_disks - max_degraded))) { |
4475 | printk(KERN_ERR "raid5: reshape_position not " | |
4476 | "on a stripe boundary\n"); | |
4477 | return -EINVAL; | |
4478 | } | |
4479 | /* here_new is the stripe we will write to */ | |
4480 | here_old = mddev->reshape_position; | |
4481 | sector_div(here_old, (mddev->chunk_size>>9)* | |
4482 | (old_disks-max_degraded)); | |
4483 | /* here_old is the first stripe that we might need to read | |
4484 | * from */ | |
4485 | if (here_new >= here_old) { | |
4486 | /* Reading from the same stripe as writing to - bad */ | |
4487 | printk(KERN_ERR "raid5: reshape_position too early for " | |
4488 | "auto-recovery - aborting.\n"); | |
4489 | return -EINVAL; | |
4490 | } | |
4491 | printk(KERN_INFO "raid5: reshape will continue\n"); | |
4492 | /* OK, we should be able to continue; */ | |
4493 | } else { | |
4494 | BUG_ON(mddev->level != mddev->new_level); | |
4495 | BUG_ON(mddev->layout != mddev->new_layout); | |
4496 | BUG_ON(mddev->chunk_size != mddev->new_chunk); | |
4497 | BUG_ON(mddev->delta_disks != 0); | |
1da177e4 | 4498 | } |
91adb564 | 4499 | |
245f46c2 N |
4500 | if (mddev->private == NULL) |
4501 | conf = setup_conf(mddev); | |
4502 | else | |
4503 | conf = mddev->private; | |
4504 | ||
91adb564 N |
4505 | if (IS_ERR(conf)) |
4506 | return PTR_ERR(conf); | |
4507 | ||
4508 | mddev->thread = conf->thread; | |
4509 | conf->thread = NULL; | |
4510 | mddev->private = conf; | |
4511 | ||
4512 | /* | |
4513 | * 0 for a fully functional array, 1 or 2 for a degraded array. | |
4514 | */ | |
4515 | list_for_each_entry(rdev, &mddev->disks, same_set) | |
4516 | if (rdev->raid_disk >= 0 && | |
4517 | test_bit(In_sync, &rdev->flags)) | |
4518 | working_disks++; | |
4519 | ||
4520 | mddev->degraded = conf->raid_disks - working_disks; | |
4521 | ||
16a53ecc | 4522 | if (mddev->degraded > conf->max_degraded) { |
1da177e4 LT |
4523 | printk(KERN_ERR "raid5: not enough operational devices for %s" |
4524 | " (%d/%d failed)\n", | |
02c2de8c | 4525 | mdname(mddev), mddev->degraded, conf->raid_disks); |
1da177e4 LT |
4526 | goto abort; |
4527 | } | |
4528 | ||
91adb564 N |
4529 | /* device size must be a multiple of chunk size */ |
4530 | mddev->dev_sectors &= ~(mddev->chunk_size / 512 - 1); | |
4531 | mddev->resync_max_sectors = mddev->dev_sectors; | |
4532 | ||
16a53ecc | 4533 | if (mddev->degraded > 0 && |
1da177e4 | 4534 | mddev->recovery_cp != MaxSector) { |
6ff8d8ec N |
4535 | if (mddev->ok_start_degraded) |
4536 | printk(KERN_WARNING | |
4537 | "raid5: starting dirty degraded array: %s" | |
4538 | "- data corruption possible.\n", | |
4539 | mdname(mddev)); | |
4540 | else { | |
4541 | printk(KERN_ERR | |
4542 | "raid5: cannot start dirty degraded array for %s\n", | |
4543 | mdname(mddev)); | |
4544 | goto abort; | |
4545 | } | |
1da177e4 LT |
4546 | } |
4547 | ||
1da177e4 LT |
4548 | if (mddev->degraded == 0) |
4549 | printk("raid5: raid level %d set %s active with %d out of %d" | |
e183eaed N |
4550 | " devices, algorithm %d\n", conf->level, mdname(mddev), |
4551 | mddev->raid_disks-mddev->degraded, mddev->raid_disks, | |
4552 | mddev->new_layout); | |
1da177e4 LT |
4553 | else |
4554 | printk(KERN_ALERT "raid5: raid level %d set %s active with %d" | |
4555 | " out of %d devices, algorithm %d\n", conf->level, | |
4556 | mdname(mddev), mddev->raid_disks - mddev->degraded, | |
e183eaed | 4557 | mddev->raid_disks, mddev->new_layout); |
1da177e4 LT |
4558 | |
4559 | print_raid5_conf(conf); | |
4560 | ||
fef9c61f | 4561 | if (conf->reshape_progress != MaxSector) { |
f6705578 | 4562 | printk("...ok start reshape thread\n"); |
fef9c61f | 4563 | conf->reshape_safe = conf->reshape_progress; |
f6705578 N |
4564 | atomic_set(&conf->reshape_stripes, 0); |
4565 | clear_bit(MD_RECOVERY_SYNC, &mddev->recovery); | |
4566 | clear_bit(MD_RECOVERY_CHECK, &mddev->recovery); | |
4567 | set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery); | |
4568 | set_bit(MD_RECOVERY_RUNNING, &mddev->recovery); | |
4569 | mddev->sync_thread = md_register_thread(md_do_sync, mddev, | |
4570 | "%s_reshape"); | |
f6705578 N |
4571 | } |
4572 | ||
1da177e4 | 4573 | /* read-ahead size must cover two whole stripes, which is |
16a53ecc | 4574 | * 2 * (datadisks) * chunksize where 'n' is the number of raid devices |
1da177e4 LT |
4575 | */ |
4576 | { | |
16a53ecc N |
4577 | int data_disks = conf->previous_raid_disks - conf->max_degraded; |
4578 | int stripe = data_disks * | |
8932c2e0 | 4579 | (mddev->chunk_size / PAGE_SIZE); |
1da177e4 LT |
4580 | if (mddev->queue->backing_dev_info.ra_pages < 2 * stripe) |
4581 | mddev->queue->backing_dev_info.ra_pages = 2 * stripe; | |
4582 | } | |
4583 | ||
4584 | /* Ok, everything is just fine now */ | |
5e55e2f5 N |
4585 | if (sysfs_create_group(&mddev->kobj, &raid5_attrs_group)) |
4586 | printk(KERN_WARNING | |
4587 | "raid5: failed to create sysfs attributes for %s\n", | |
4588 | mdname(mddev)); | |
7a5febe9 | 4589 | |
91adb564 N |
4590 | mddev->queue->queue_lock = &conf->device_lock; |
4591 | ||
7a5febe9 | 4592 | mddev->queue->unplug_fn = raid5_unplug_device; |
f022b2fd | 4593 | mddev->queue->backing_dev_info.congested_data = mddev; |
041ae52e | 4594 | mddev->queue->backing_dev_info.congested_fn = raid5_congested; |
f022b2fd | 4595 | |
1f403624 | 4596 | md_set_array_sectors(mddev, raid5_size(mddev, 0, 0)); |
7a5febe9 | 4597 | |
23032a0e RBJ |
4598 | blk_queue_merge_bvec(mddev->queue, raid5_mergeable_bvec); |
4599 | ||
1da177e4 LT |
4600 | return 0; |
4601 | abort: | |
e0cf8f04 | 4602 | md_unregister_thread(mddev->thread); |
91adb564 | 4603 | mddev->thread = NULL; |
1da177e4 | 4604 | if (conf) { |
91adb564 | 4605 | shrink_stripes(conf); |
1da177e4 | 4606 | print_raid5_conf(conf); |
16a53ecc | 4607 | safe_put_page(conf->spare_page); |
b55e6bfc | 4608 | kfree(conf->disks); |
fccddba0 | 4609 | kfree(conf->stripe_hashtbl); |
1da177e4 LT |
4610 | kfree(conf); |
4611 | } | |
4612 | mddev->private = NULL; | |
4613 | printk(KERN_ALERT "raid5: failed to run raid set %s\n", mdname(mddev)); | |
4614 | return -EIO; | |
4615 | } | |
4616 | ||
4617 | ||
4618 | ||
3f294f4f | 4619 | static int stop(mddev_t *mddev) |
1da177e4 LT |
4620 | { |
4621 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; | |
4622 | ||
4623 | md_unregister_thread(mddev->thread); | |
4624 | mddev->thread = NULL; | |
4625 | shrink_stripes(conf); | |
fccddba0 | 4626 | kfree(conf->stripe_hashtbl); |
041ae52e | 4627 | mddev->queue->backing_dev_info.congested_fn = NULL; |
1da177e4 | 4628 | blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/ |
007583c9 | 4629 | sysfs_remove_group(&mddev->kobj, &raid5_attrs_group); |
b55e6bfc | 4630 | kfree(conf->disks); |
96de1e66 | 4631 | kfree(conf); |
1da177e4 LT |
4632 | mddev->private = NULL; |
4633 | return 0; | |
4634 | } | |
4635 | ||
45b4233c | 4636 | #ifdef DEBUG |
d710e138 | 4637 | static void print_sh(struct seq_file *seq, struct stripe_head *sh) |
1da177e4 LT |
4638 | { |
4639 | int i; | |
4640 | ||
16a53ecc N |
4641 | seq_printf(seq, "sh %llu, pd_idx %d, state %ld.\n", |
4642 | (unsigned long long)sh->sector, sh->pd_idx, sh->state); | |
4643 | seq_printf(seq, "sh %llu, count %d.\n", | |
4644 | (unsigned long long)sh->sector, atomic_read(&sh->count)); | |
4645 | seq_printf(seq, "sh %llu, ", (unsigned long long)sh->sector); | |
7ecaa1e6 | 4646 | for (i = 0; i < sh->disks; i++) { |
16a53ecc N |
4647 | seq_printf(seq, "(cache%d: %p %ld) ", |
4648 | i, sh->dev[i].page, sh->dev[i].flags); | |
1da177e4 | 4649 | } |
16a53ecc | 4650 | seq_printf(seq, "\n"); |
1da177e4 LT |
4651 | } |
4652 | ||
d710e138 | 4653 | static void printall(struct seq_file *seq, raid5_conf_t *conf) |
1da177e4 LT |
4654 | { |
4655 | struct stripe_head *sh; | |
fccddba0 | 4656 | struct hlist_node *hn; |
1da177e4 LT |
4657 | int i; |
4658 | ||
4659 | spin_lock_irq(&conf->device_lock); | |
4660 | for (i = 0; i < NR_HASH; i++) { | |
fccddba0 | 4661 | hlist_for_each_entry(sh, hn, &conf->stripe_hashtbl[i], hash) { |
1da177e4 LT |
4662 | if (sh->raid_conf != conf) |
4663 | continue; | |
16a53ecc | 4664 | print_sh(seq, sh); |
1da177e4 LT |
4665 | } |
4666 | } | |
4667 | spin_unlock_irq(&conf->device_lock); | |
4668 | } | |
4669 | #endif | |
4670 | ||
d710e138 | 4671 | static void status(struct seq_file *seq, mddev_t *mddev) |
1da177e4 LT |
4672 | { |
4673 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; | |
4674 | int i; | |
4675 | ||
4676 | seq_printf (seq, " level %d, %dk chunk, algorithm %d", mddev->level, mddev->chunk_size >> 10, mddev->layout); | |
02c2de8c | 4677 | seq_printf (seq, " [%d/%d] [", conf->raid_disks, conf->raid_disks - mddev->degraded); |
1da177e4 LT |
4678 | for (i = 0; i < conf->raid_disks; i++) |
4679 | seq_printf (seq, "%s", | |
4680 | conf->disks[i].rdev && | |
b2d444d7 | 4681 | test_bit(In_sync, &conf->disks[i].rdev->flags) ? "U" : "_"); |
1da177e4 | 4682 | seq_printf (seq, "]"); |
45b4233c | 4683 | #ifdef DEBUG |
16a53ecc N |
4684 | seq_printf (seq, "\n"); |
4685 | printall(seq, conf); | |
1da177e4 LT |
4686 | #endif |
4687 | } | |
4688 | ||
4689 | static void print_raid5_conf (raid5_conf_t *conf) | |
4690 | { | |
4691 | int i; | |
4692 | struct disk_info *tmp; | |
4693 | ||
4694 | printk("RAID5 conf printout:\n"); | |
4695 | if (!conf) { | |
4696 | printk("(conf==NULL)\n"); | |
4697 | return; | |
4698 | } | |
02c2de8c N |
4699 | printk(" --- rd:%d wd:%d\n", conf->raid_disks, |
4700 | conf->raid_disks - conf->mddev->degraded); | |
1da177e4 LT |
4701 | |
4702 | for (i = 0; i < conf->raid_disks; i++) { | |
4703 | char b[BDEVNAME_SIZE]; | |
4704 | tmp = conf->disks + i; | |
4705 | if (tmp->rdev) | |
4706 | printk(" disk %d, o:%d, dev:%s\n", | |
b2d444d7 | 4707 | i, !test_bit(Faulty, &tmp->rdev->flags), |
1da177e4 LT |
4708 | bdevname(tmp->rdev->bdev,b)); |
4709 | } | |
4710 | } | |
4711 | ||
4712 | static int raid5_spare_active(mddev_t *mddev) | |
4713 | { | |
4714 | int i; | |
4715 | raid5_conf_t *conf = mddev->private; | |
4716 | struct disk_info *tmp; | |
4717 | ||
4718 | for (i = 0; i < conf->raid_disks; i++) { | |
4719 | tmp = conf->disks + i; | |
4720 | if (tmp->rdev | |
b2d444d7 | 4721 | && !test_bit(Faulty, &tmp->rdev->flags) |
c04be0aa N |
4722 | && !test_and_set_bit(In_sync, &tmp->rdev->flags)) { |
4723 | unsigned long flags; | |
4724 | spin_lock_irqsave(&conf->device_lock, flags); | |
1da177e4 | 4725 | mddev->degraded--; |
c04be0aa | 4726 | spin_unlock_irqrestore(&conf->device_lock, flags); |
1da177e4 LT |
4727 | } |
4728 | } | |
4729 | print_raid5_conf(conf); | |
4730 | return 0; | |
4731 | } | |
4732 | ||
4733 | static int raid5_remove_disk(mddev_t *mddev, int number) | |
4734 | { | |
4735 | raid5_conf_t *conf = mddev->private; | |
4736 | int err = 0; | |
4737 | mdk_rdev_t *rdev; | |
4738 | struct disk_info *p = conf->disks + number; | |
4739 | ||
4740 | print_raid5_conf(conf); | |
4741 | rdev = p->rdev; | |
4742 | if (rdev) { | |
ec32a2bd N |
4743 | if (number >= conf->raid_disks && |
4744 | conf->reshape_progress == MaxSector) | |
4745 | clear_bit(In_sync, &rdev->flags); | |
4746 | ||
b2d444d7 | 4747 | if (test_bit(In_sync, &rdev->flags) || |
1da177e4 LT |
4748 | atomic_read(&rdev->nr_pending)) { |
4749 | err = -EBUSY; | |
4750 | goto abort; | |
4751 | } | |
dfc70645 N |
4752 | /* Only remove non-faulty devices if recovery |
4753 | * isn't possible. | |
4754 | */ | |
4755 | if (!test_bit(Faulty, &rdev->flags) && | |
ec32a2bd N |
4756 | mddev->degraded <= conf->max_degraded && |
4757 | number < conf->raid_disks) { | |
dfc70645 N |
4758 | err = -EBUSY; |
4759 | goto abort; | |
4760 | } | |
1da177e4 | 4761 | p->rdev = NULL; |
fbd568a3 | 4762 | synchronize_rcu(); |
1da177e4 LT |
4763 | if (atomic_read(&rdev->nr_pending)) { |
4764 | /* lost the race, try later */ | |
4765 | err = -EBUSY; | |
4766 | p->rdev = rdev; | |
4767 | } | |
4768 | } | |
4769 | abort: | |
4770 | ||
4771 | print_raid5_conf(conf); | |
4772 | return err; | |
4773 | } | |
4774 | ||
4775 | static int raid5_add_disk(mddev_t *mddev, mdk_rdev_t *rdev) | |
4776 | { | |
4777 | raid5_conf_t *conf = mddev->private; | |
199050ea | 4778 | int err = -EEXIST; |
1da177e4 LT |
4779 | int disk; |
4780 | struct disk_info *p; | |
6c2fce2e NB |
4781 | int first = 0; |
4782 | int last = conf->raid_disks - 1; | |
1da177e4 | 4783 | |
16a53ecc | 4784 | if (mddev->degraded > conf->max_degraded) |
1da177e4 | 4785 | /* no point adding a device */ |
199050ea | 4786 | return -EINVAL; |
1da177e4 | 4787 | |
6c2fce2e NB |
4788 | if (rdev->raid_disk >= 0) |
4789 | first = last = rdev->raid_disk; | |
1da177e4 LT |
4790 | |
4791 | /* | |
16a53ecc N |
4792 | * find the disk ... but prefer rdev->saved_raid_disk |
4793 | * if possible. | |
1da177e4 | 4794 | */ |
16a53ecc | 4795 | if (rdev->saved_raid_disk >= 0 && |
6c2fce2e | 4796 | rdev->saved_raid_disk >= first && |
16a53ecc N |
4797 | conf->disks[rdev->saved_raid_disk].rdev == NULL) |
4798 | disk = rdev->saved_raid_disk; | |
4799 | else | |
6c2fce2e NB |
4800 | disk = first; |
4801 | for ( ; disk <= last ; disk++) | |
1da177e4 | 4802 | if ((p=conf->disks + disk)->rdev == NULL) { |
b2d444d7 | 4803 | clear_bit(In_sync, &rdev->flags); |
1da177e4 | 4804 | rdev->raid_disk = disk; |
199050ea | 4805 | err = 0; |
72626685 N |
4806 | if (rdev->saved_raid_disk != disk) |
4807 | conf->fullsync = 1; | |
d6065f7b | 4808 | rcu_assign_pointer(p->rdev, rdev); |
1da177e4 LT |
4809 | break; |
4810 | } | |
4811 | print_raid5_conf(conf); | |
199050ea | 4812 | return err; |
1da177e4 LT |
4813 | } |
4814 | ||
4815 | static int raid5_resize(mddev_t *mddev, sector_t sectors) | |
4816 | { | |
4817 | /* no resync is happening, and there is enough space | |
4818 | * on all devices, so we can resize. | |
4819 | * We need to make sure resync covers any new space. | |
4820 | * If the array is shrinking we should possibly wait until | |
4821 | * any io in the removed space completes, but it hardly seems | |
4822 | * worth it. | |
4823 | */ | |
4824 | sectors &= ~((sector_t)mddev->chunk_size/512 - 1); | |
1f403624 DW |
4825 | md_set_array_sectors(mddev, raid5_size(mddev, sectors, |
4826 | mddev->raid_disks)); | |
b522adcd DW |
4827 | if (mddev->array_sectors > |
4828 | raid5_size(mddev, sectors, mddev->raid_disks)) | |
4829 | return -EINVAL; | |
f233ea5c | 4830 | set_capacity(mddev->gendisk, mddev->array_sectors); |
44ce6294 | 4831 | mddev->changed = 1; |
58c0fed4 AN |
4832 | if (sectors > mddev->dev_sectors && mddev->recovery_cp == MaxSector) { |
4833 | mddev->recovery_cp = mddev->dev_sectors; | |
1da177e4 LT |
4834 | set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); |
4835 | } | |
58c0fed4 | 4836 | mddev->dev_sectors = sectors; |
4b5c7ae8 | 4837 | mddev->resync_max_sectors = sectors; |
1da177e4 LT |
4838 | return 0; |
4839 | } | |
4840 | ||
63c70c4f | 4841 | static int raid5_check_reshape(mddev_t *mddev) |
29269553 N |
4842 | { |
4843 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
29269553 | 4844 | |
88ce4930 N |
4845 | if (mddev->delta_disks == 0 && |
4846 | mddev->new_layout == mddev->layout && | |
4847 | mddev->new_chunk == mddev->chunk_size) | |
4848 | return -EINVAL; /* nothing to do */ | |
dba034ee N |
4849 | if (mddev->bitmap) |
4850 | /* Cannot grow a bitmap yet */ | |
4851 | return -EBUSY; | |
ec32a2bd N |
4852 | if (mddev->degraded > conf->max_degraded) |
4853 | return -EINVAL; | |
4854 | if (mddev->delta_disks < 0) { | |
4855 | /* We might be able to shrink, but the devices must | |
4856 | * be made bigger first. | |
4857 | * For raid6, 4 is the minimum size. | |
4858 | * Otherwise 2 is the minimum | |
4859 | */ | |
4860 | int min = 2; | |
4861 | if (mddev->level == 6) | |
4862 | min = 4; | |
4863 | if (mddev->raid_disks + mddev->delta_disks < min) | |
4864 | return -EINVAL; | |
4865 | } | |
29269553 N |
4866 | |
4867 | /* Can only proceed if there are plenty of stripe_heads. | |
4868 | * We need a minimum of one full stripe,, and for sensible progress | |
4869 | * it is best to have about 4 times that. | |
4870 | * If we require 4 times, then the default 256 4K stripe_heads will | |
4871 | * allow for chunk sizes up to 256K, which is probably OK. | |
4872 | * If the chunk size is greater, user-space should request more | |
4873 | * stripe_heads first. | |
4874 | */ | |
63c70c4f N |
4875 | if ((mddev->chunk_size / STRIPE_SIZE) * 4 > conf->max_nr_stripes || |
4876 | (mddev->new_chunk / STRIPE_SIZE) * 4 > conf->max_nr_stripes) { | |
29269553 | 4877 | printk(KERN_WARNING "raid5: reshape: not enough stripes. Needed %lu\n", |
784052ec N |
4878 | (max(mddev->chunk_size, mddev->new_chunk) |
4879 | / STRIPE_SIZE)*4); | |
29269553 N |
4880 | return -ENOSPC; |
4881 | } | |
4882 | ||
ec32a2bd | 4883 | return resize_stripes(conf, conf->raid_disks + mddev->delta_disks); |
63c70c4f N |
4884 | } |
4885 | ||
4886 | static int raid5_start_reshape(mddev_t *mddev) | |
4887 | { | |
4888 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4889 | mdk_rdev_t *rdev; | |
63c70c4f N |
4890 | int spares = 0; |
4891 | int added_devices = 0; | |
c04be0aa | 4892 | unsigned long flags; |
63c70c4f | 4893 | |
f416885e | 4894 | if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) |
63c70c4f N |
4895 | return -EBUSY; |
4896 | ||
159ec1fc | 4897 | list_for_each_entry(rdev, &mddev->disks, same_set) |
29269553 N |
4898 | if (rdev->raid_disk < 0 && |
4899 | !test_bit(Faulty, &rdev->flags)) | |
4900 | spares++; | |
63c70c4f | 4901 | |
f416885e | 4902 | if (spares - mddev->degraded < mddev->delta_disks - conf->max_degraded) |
29269553 N |
4903 | /* Not enough devices even to make a degraded array |
4904 | * of that size | |
4905 | */ | |
4906 | return -EINVAL; | |
4907 | ||
ec32a2bd N |
4908 | /* Refuse to reduce size of the array. Any reductions in |
4909 | * array size must be through explicit setting of array_size | |
4910 | * attribute. | |
4911 | */ | |
4912 | if (raid5_size(mddev, 0, conf->raid_disks + mddev->delta_disks) | |
4913 | < mddev->array_sectors) { | |
4914 | printk(KERN_ERR "md: %s: array size must be reduced " | |
4915 | "before number of disks\n", mdname(mddev)); | |
4916 | return -EINVAL; | |
4917 | } | |
4918 | ||
f6705578 | 4919 | atomic_set(&conf->reshape_stripes, 0); |
29269553 N |
4920 | spin_lock_irq(&conf->device_lock); |
4921 | conf->previous_raid_disks = conf->raid_disks; | |
63c70c4f | 4922 | conf->raid_disks += mddev->delta_disks; |
88ce4930 N |
4923 | conf->prev_chunk = conf->chunk_size; |
4924 | conf->chunk_size = mddev->new_chunk; | |
4925 | conf->prev_algo = conf->algorithm; | |
4926 | conf->algorithm = mddev->new_layout; | |
fef9c61f N |
4927 | if (mddev->delta_disks < 0) |
4928 | conf->reshape_progress = raid5_size(mddev, 0, 0); | |
4929 | else | |
4930 | conf->reshape_progress = 0; | |
4931 | conf->reshape_safe = conf->reshape_progress; | |
86b42c71 | 4932 | conf->generation++; |
29269553 N |
4933 | spin_unlock_irq(&conf->device_lock); |
4934 | ||
4935 | /* Add some new drives, as many as will fit. | |
4936 | * We know there are enough to make the newly sized array work. | |
4937 | */ | |
159ec1fc | 4938 | list_for_each_entry(rdev, &mddev->disks, same_set) |
29269553 N |
4939 | if (rdev->raid_disk < 0 && |
4940 | !test_bit(Faulty, &rdev->flags)) { | |
199050ea | 4941 | if (raid5_add_disk(mddev, rdev) == 0) { |
29269553 N |
4942 | char nm[20]; |
4943 | set_bit(In_sync, &rdev->flags); | |
29269553 | 4944 | added_devices++; |
5fd6c1dc | 4945 | rdev->recovery_offset = 0; |
29269553 | 4946 | sprintf(nm, "rd%d", rdev->raid_disk); |
5e55e2f5 N |
4947 | if (sysfs_create_link(&mddev->kobj, |
4948 | &rdev->kobj, nm)) | |
4949 | printk(KERN_WARNING | |
4950 | "raid5: failed to create " | |
4951 | " link %s for %s\n", | |
4952 | nm, mdname(mddev)); | |
29269553 N |
4953 | } else |
4954 | break; | |
4955 | } | |
4956 | ||
ec32a2bd N |
4957 | if (mddev->delta_disks > 0) { |
4958 | spin_lock_irqsave(&conf->device_lock, flags); | |
4959 | mddev->degraded = (conf->raid_disks - conf->previous_raid_disks) | |
4960 | - added_devices; | |
4961 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
4962 | } | |
63c70c4f | 4963 | mddev->raid_disks = conf->raid_disks; |
f6705578 | 4964 | mddev->reshape_position = 0; |
850b2b42 | 4965 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
f6705578 | 4966 | |
29269553 N |
4967 | clear_bit(MD_RECOVERY_SYNC, &mddev->recovery); |
4968 | clear_bit(MD_RECOVERY_CHECK, &mddev->recovery); | |
4969 | set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery); | |
4970 | set_bit(MD_RECOVERY_RUNNING, &mddev->recovery); | |
4971 | mddev->sync_thread = md_register_thread(md_do_sync, mddev, | |
4972 | "%s_reshape"); | |
4973 | if (!mddev->sync_thread) { | |
4974 | mddev->recovery = 0; | |
4975 | spin_lock_irq(&conf->device_lock); | |
4976 | mddev->raid_disks = conf->raid_disks = conf->previous_raid_disks; | |
fef9c61f | 4977 | conf->reshape_progress = MaxSector; |
29269553 N |
4978 | spin_unlock_irq(&conf->device_lock); |
4979 | return -EAGAIN; | |
4980 | } | |
c8f517c4 | 4981 | conf->reshape_checkpoint = jiffies; |
29269553 N |
4982 | md_wakeup_thread(mddev->sync_thread); |
4983 | md_new_event(mddev); | |
4984 | return 0; | |
4985 | } | |
29269553 | 4986 | |
ec32a2bd N |
4987 | /* This is called from the reshape thread and should make any |
4988 | * changes needed in 'conf' | |
4989 | */ | |
29269553 N |
4990 | static void end_reshape(raid5_conf_t *conf) |
4991 | { | |
29269553 | 4992 | |
f6705578 | 4993 | if (!test_bit(MD_RECOVERY_INTR, &conf->mddev->recovery)) { |
f6705578 | 4994 | |
f6705578 | 4995 | spin_lock_irq(&conf->device_lock); |
cea9c228 | 4996 | conf->previous_raid_disks = conf->raid_disks; |
fef9c61f | 4997 | conf->reshape_progress = MaxSector; |
f6705578 | 4998 | spin_unlock_irq(&conf->device_lock); |
b0f9ec04 | 4999 | wake_up(&conf->wait_for_overlap); |
16a53ecc N |
5000 | |
5001 | /* read-ahead size must cover two whole stripes, which is | |
5002 | * 2 * (datadisks) * chunksize where 'n' is the number of raid devices | |
5003 | */ | |
5004 | { | |
cea9c228 N |
5005 | int data_disks = conf->raid_disks - conf->max_degraded; |
5006 | int stripe = data_disks * (conf->chunk_size | |
5007 | / PAGE_SIZE); | |
16a53ecc N |
5008 | if (conf->mddev->queue->backing_dev_info.ra_pages < 2 * stripe) |
5009 | conf->mddev->queue->backing_dev_info.ra_pages = 2 * stripe; | |
5010 | } | |
29269553 | 5011 | } |
29269553 N |
5012 | } |
5013 | ||
ec32a2bd N |
5014 | /* This is called from the raid5d thread with mddev_lock held. |
5015 | * It makes config changes to the device. | |
5016 | */ | |
cea9c228 N |
5017 | static void raid5_finish_reshape(mddev_t *mddev) |
5018 | { | |
5019 | struct block_device *bdev; | |
88ce4930 | 5020 | raid5_conf_t *conf = mddev_to_conf(mddev); |
cea9c228 N |
5021 | |
5022 | if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery)) { | |
5023 | ||
ec32a2bd N |
5024 | if (mddev->delta_disks > 0) { |
5025 | md_set_array_sectors(mddev, raid5_size(mddev, 0, 0)); | |
5026 | set_capacity(mddev->gendisk, mddev->array_sectors); | |
5027 | mddev->changed = 1; | |
5028 | ||
5029 | bdev = bdget_disk(mddev->gendisk, 0); | |
5030 | if (bdev) { | |
5031 | mutex_lock(&bdev->bd_inode->i_mutex); | |
5032 | i_size_write(bdev->bd_inode, | |
5033 | (loff_t)mddev->array_sectors << 9); | |
5034 | mutex_unlock(&bdev->bd_inode->i_mutex); | |
5035 | bdput(bdev); | |
5036 | } | |
5037 | } else { | |
5038 | int d; | |
ec32a2bd N |
5039 | mddev->degraded = conf->raid_disks; |
5040 | for (d = 0; d < conf->raid_disks ; d++) | |
5041 | if (conf->disks[d].rdev && | |
5042 | test_bit(In_sync, | |
5043 | &conf->disks[d].rdev->flags)) | |
5044 | mddev->degraded--; | |
5045 | for (d = conf->raid_disks ; | |
5046 | d < conf->raid_disks - mddev->delta_disks; | |
5047 | d++) | |
5048 | raid5_remove_disk(mddev, d); | |
cea9c228 | 5049 | } |
88ce4930 N |
5050 | mddev->layout = conf->algorithm; |
5051 | mddev->chunk_size = conf->chunk_size; | |
ec32a2bd N |
5052 | mddev->reshape_position = MaxSector; |
5053 | mddev->delta_disks = 0; | |
cea9c228 N |
5054 | } |
5055 | } | |
5056 | ||
72626685 N |
5057 | static void raid5_quiesce(mddev_t *mddev, int state) |
5058 | { | |
5059 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
5060 | ||
5061 | switch(state) { | |
e464eafd N |
5062 | case 2: /* resume for a suspend */ |
5063 | wake_up(&conf->wait_for_overlap); | |
5064 | break; | |
5065 | ||
72626685 N |
5066 | case 1: /* stop all writes */ |
5067 | spin_lock_irq(&conf->device_lock); | |
5068 | conf->quiesce = 1; | |
5069 | wait_event_lock_irq(conf->wait_for_stripe, | |
46031f9a RBJ |
5070 | atomic_read(&conf->active_stripes) == 0 && |
5071 | atomic_read(&conf->active_aligned_reads) == 0, | |
72626685 N |
5072 | conf->device_lock, /* nothing */); |
5073 | spin_unlock_irq(&conf->device_lock); | |
5074 | break; | |
5075 | ||
5076 | case 0: /* re-enable writes */ | |
5077 | spin_lock_irq(&conf->device_lock); | |
5078 | conf->quiesce = 0; | |
5079 | wake_up(&conf->wait_for_stripe); | |
e464eafd | 5080 | wake_up(&conf->wait_for_overlap); |
72626685 N |
5081 | spin_unlock_irq(&conf->device_lock); |
5082 | break; | |
5083 | } | |
72626685 | 5084 | } |
b15c2e57 | 5085 | |
d562b0c4 N |
5086 | |
5087 | static void *raid5_takeover_raid1(mddev_t *mddev) | |
5088 | { | |
5089 | int chunksect; | |
5090 | ||
5091 | if (mddev->raid_disks != 2 || | |
5092 | mddev->degraded > 1) | |
5093 | return ERR_PTR(-EINVAL); | |
5094 | ||
5095 | /* Should check if there are write-behind devices? */ | |
5096 | ||
5097 | chunksect = 64*2; /* 64K by default */ | |
5098 | ||
5099 | /* The array must be an exact multiple of chunksize */ | |
5100 | while (chunksect && (mddev->array_sectors & (chunksect-1))) | |
5101 | chunksect >>= 1; | |
5102 | ||
5103 | if ((chunksect<<9) < STRIPE_SIZE) | |
5104 | /* array size does not allow a suitable chunk size */ | |
5105 | return ERR_PTR(-EINVAL); | |
5106 | ||
5107 | mddev->new_level = 5; | |
5108 | mddev->new_layout = ALGORITHM_LEFT_SYMMETRIC; | |
5109 | mddev->new_chunk = chunksect << 9; | |
5110 | ||
5111 | return setup_conf(mddev); | |
5112 | } | |
5113 | ||
fc9739c6 N |
5114 | static void *raid5_takeover_raid6(mddev_t *mddev) |
5115 | { | |
5116 | int new_layout; | |
5117 | ||
5118 | switch (mddev->layout) { | |
5119 | case ALGORITHM_LEFT_ASYMMETRIC_6: | |
5120 | new_layout = ALGORITHM_LEFT_ASYMMETRIC; | |
5121 | break; | |
5122 | case ALGORITHM_RIGHT_ASYMMETRIC_6: | |
5123 | new_layout = ALGORITHM_RIGHT_ASYMMETRIC; | |
5124 | break; | |
5125 | case ALGORITHM_LEFT_SYMMETRIC_6: | |
5126 | new_layout = ALGORITHM_LEFT_SYMMETRIC; | |
5127 | break; | |
5128 | case ALGORITHM_RIGHT_SYMMETRIC_6: | |
5129 | new_layout = ALGORITHM_RIGHT_SYMMETRIC; | |
5130 | break; | |
5131 | case ALGORITHM_PARITY_0_6: | |
5132 | new_layout = ALGORITHM_PARITY_0; | |
5133 | break; | |
5134 | case ALGORITHM_PARITY_N: | |
5135 | new_layout = ALGORITHM_PARITY_N; | |
5136 | break; | |
5137 | default: | |
5138 | return ERR_PTR(-EINVAL); | |
5139 | } | |
5140 | mddev->new_level = 5; | |
5141 | mddev->new_layout = new_layout; | |
5142 | mddev->delta_disks = -1; | |
5143 | mddev->raid_disks -= 1; | |
5144 | return setup_conf(mddev); | |
5145 | } | |
5146 | ||
d562b0c4 | 5147 | |
b3546035 N |
5148 | static int raid5_reconfig(mddev_t *mddev, int new_layout, int new_chunk) |
5149 | { | |
88ce4930 N |
5150 | /* For a 2-drive array, the layout and chunk size can be changed |
5151 | * immediately as not restriping is needed. | |
5152 | * For larger arrays we record the new value - after validation | |
5153 | * to be used by a reshape pass. | |
b3546035 N |
5154 | */ |
5155 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
5156 | ||
5157 | if (new_layout >= 0 && !algorithm_valid_raid5(new_layout)) | |
5158 | return -EINVAL; | |
5159 | if (new_chunk > 0) { | |
5160 | if (new_chunk & (new_chunk-1)) | |
5161 | /* not a power of 2 */ | |
5162 | return -EINVAL; | |
5163 | if (new_chunk < PAGE_SIZE) | |
5164 | return -EINVAL; | |
5165 | if (mddev->array_sectors & ((new_chunk>>9)-1)) | |
5166 | /* not factor of array size */ | |
5167 | return -EINVAL; | |
5168 | } | |
5169 | ||
5170 | /* They look valid */ | |
5171 | ||
88ce4930 | 5172 | if (mddev->raid_disks == 2) { |
b3546035 | 5173 | |
88ce4930 N |
5174 | if (new_layout >= 0) { |
5175 | conf->algorithm = new_layout; | |
5176 | mddev->layout = mddev->new_layout = new_layout; | |
5177 | } | |
5178 | if (new_chunk > 0) { | |
5179 | conf->chunk_size = new_chunk; | |
5180 | mddev->chunk_size = mddev->new_chunk = new_chunk; | |
5181 | } | |
5182 | set_bit(MD_CHANGE_DEVS, &mddev->flags); | |
5183 | md_wakeup_thread(mddev->thread); | |
5184 | } else { | |
5185 | if (new_layout >= 0) | |
5186 | mddev->new_layout = new_layout; | |
5187 | if (new_chunk > 0) | |
5188 | mddev->new_chunk = new_chunk; | |
b3546035 | 5189 | } |
88ce4930 N |
5190 | return 0; |
5191 | } | |
5192 | ||
5193 | static int raid6_reconfig(mddev_t *mddev, int new_layout, int new_chunk) | |
5194 | { | |
5195 | if (new_layout >= 0 && !algorithm_valid_raid6(new_layout)) | |
5196 | return -EINVAL; | |
b3546035 | 5197 | if (new_chunk > 0) { |
88ce4930 N |
5198 | if (new_chunk & (new_chunk-1)) |
5199 | /* not a power of 2 */ | |
5200 | return -EINVAL; | |
5201 | if (new_chunk < PAGE_SIZE) | |
5202 | return -EINVAL; | |
5203 | if (mddev->array_sectors & ((new_chunk>>9)-1)) | |
5204 | /* not factor of array size */ | |
5205 | return -EINVAL; | |
b3546035 | 5206 | } |
88ce4930 N |
5207 | |
5208 | /* They look valid */ | |
5209 | ||
5210 | if (new_layout >= 0) | |
5211 | mddev->new_layout = new_layout; | |
5212 | if (new_chunk > 0) | |
5213 | mddev->new_chunk = new_chunk; | |
5214 | ||
b3546035 N |
5215 | return 0; |
5216 | } | |
5217 | ||
d562b0c4 N |
5218 | static void *raid5_takeover(mddev_t *mddev) |
5219 | { | |
5220 | /* raid5 can take over: | |
5221 | * raid0 - if all devices are the same - make it a raid4 layout | |
5222 | * raid1 - if there are two drives. We need to know the chunk size | |
5223 | * raid4 - trivial - just use a raid4 layout. | |
5224 | * raid6 - Providing it is a *_6 layout | |
5225 | * | |
5226 | * For now, just do raid1 | |
5227 | */ | |
5228 | ||
5229 | if (mddev->level == 1) | |
5230 | return raid5_takeover_raid1(mddev); | |
e9d4758f N |
5231 | if (mddev->level == 4) { |
5232 | mddev->new_layout = ALGORITHM_PARITY_N; | |
5233 | mddev->new_level = 5; | |
5234 | return setup_conf(mddev); | |
5235 | } | |
fc9739c6 N |
5236 | if (mddev->level == 6) |
5237 | return raid5_takeover_raid6(mddev); | |
d562b0c4 N |
5238 | |
5239 | return ERR_PTR(-EINVAL); | |
5240 | } | |
5241 | ||
5242 | ||
245f46c2 N |
5243 | static struct mdk_personality raid5_personality; |
5244 | ||
5245 | static void *raid6_takeover(mddev_t *mddev) | |
5246 | { | |
5247 | /* Currently can only take over a raid5. We map the | |
5248 | * personality to an equivalent raid6 personality | |
5249 | * with the Q block at the end. | |
5250 | */ | |
5251 | int new_layout; | |
5252 | ||
5253 | if (mddev->pers != &raid5_personality) | |
5254 | return ERR_PTR(-EINVAL); | |
5255 | if (mddev->degraded > 1) | |
5256 | return ERR_PTR(-EINVAL); | |
5257 | if (mddev->raid_disks > 253) | |
5258 | return ERR_PTR(-EINVAL); | |
5259 | if (mddev->raid_disks < 3) | |
5260 | return ERR_PTR(-EINVAL); | |
5261 | ||
5262 | switch (mddev->layout) { | |
5263 | case ALGORITHM_LEFT_ASYMMETRIC: | |
5264 | new_layout = ALGORITHM_LEFT_ASYMMETRIC_6; | |
5265 | break; | |
5266 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
5267 | new_layout = ALGORITHM_RIGHT_ASYMMETRIC_6; | |
5268 | break; | |
5269 | case ALGORITHM_LEFT_SYMMETRIC: | |
5270 | new_layout = ALGORITHM_LEFT_SYMMETRIC_6; | |
5271 | break; | |
5272 | case ALGORITHM_RIGHT_SYMMETRIC: | |
5273 | new_layout = ALGORITHM_RIGHT_SYMMETRIC_6; | |
5274 | break; | |
5275 | case ALGORITHM_PARITY_0: | |
5276 | new_layout = ALGORITHM_PARITY_0_6; | |
5277 | break; | |
5278 | case ALGORITHM_PARITY_N: | |
5279 | new_layout = ALGORITHM_PARITY_N; | |
5280 | break; | |
5281 | default: | |
5282 | return ERR_PTR(-EINVAL); | |
5283 | } | |
5284 | mddev->new_level = 6; | |
5285 | mddev->new_layout = new_layout; | |
5286 | mddev->delta_disks = 1; | |
5287 | mddev->raid_disks += 1; | |
5288 | return setup_conf(mddev); | |
5289 | } | |
5290 | ||
5291 | ||
16a53ecc N |
5292 | static struct mdk_personality raid6_personality = |
5293 | { | |
5294 | .name = "raid6", | |
5295 | .level = 6, | |
5296 | .owner = THIS_MODULE, | |
5297 | .make_request = make_request, | |
5298 | .run = run, | |
5299 | .stop = stop, | |
5300 | .status = status, | |
5301 | .error_handler = error, | |
5302 | .hot_add_disk = raid5_add_disk, | |
5303 | .hot_remove_disk= raid5_remove_disk, | |
5304 | .spare_active = raid5_spare_active, | |
5305 | .sync_request = sync_request, | |
5306 | .resize = raid5_resize, | |
80c3a6ce | 5307 | .size = raid5_size, |
f416885e N |
5308 | .check_reshape = raid5_check_reshape, |
5309 | .start_reshape = raid5_start_reshape, | |
cea9c228 | 5310 | .finish_reshape = raid5_finish_reshape, |
16a53ecc | 5311 | .quiesce = raid5_quiesce, |
245f46c2 | 5312 | .takeover = raid6_takeover, |
88ce4930 | 5313 | .reconfig = raid6_reconfig, |
16a53ecc | 5314 | }; |
2604b703 | 5315 | static struct mdk_personality raid5_personality = |
1da177e4 LT |
5316 | { |
5317 | .name = "raid5", | |
2604b703 | 5318 | .level = 5, |
1da177e4 LT |
5319 | .owner = THIS_MODULE, |
5320 | .make_request = make_request, | |
5321 | .run = run, | |
5322 | .stop = stop, | |
5323 | .status = status, | |
5324 | .error_handler = error, | |
5325 | .hot_add_disk = raid5_add_disk, | |
5326 | .hot_remove_disk= raid5_remove_disk, | |
5327 | .spare_active = raid5_spare_active, | |
5328 | .sync_request = sync_request, | |
5329 | .resize = raid5_resize, | |
80c3a6ce | 5330 | .size = raid5_size, |
63c70c4f N |
5331 | .check_reshape = raid5_check_reshape, |
5332 | .start_reshape = raid5_start_reshape, | |
cea9c228 | 5333 | .finish_reshape = raid5_finish_reshape, |
72626685 | 5334 | .quiesce = raid5_quiesce, |
d562b0c4 | 5335 | .takeover = raid5_takeover, |
b3546035 | 5336 | .reconfig = raid5_reconfig, |
1da177e4 LT |
5337 | }; |
5338 | ||
2604b703 | 5339 | static struct mdk_personality raid4_personality = |
1da177e4 | 5340 | { |
2604b703 N |
5341 | .name = "raid4", |
5342 | .level = 4, | |
5343 | .owner = THIS_MODULE, | |
5344 | .make_request = make_request, | |
5345 | .run = run, | |
5346 | .stop = stop, | |
5347 | .status = status, | |
5348 | .error_handler = error, | |
5349 | .hot_add_disk = raid5_add_disk, | |
5350 | .hot_remove_disk= raid5_remove_disk, | |
5351 | .spare_active = raid5_spare_active, | |
5352 | .sync_request = sync_request, | |
5353 | .resize = raid5_resize, | |
80c3a6ce | 5354 | .size = raid5_size, |
3d37890b N |
5355 | .check_reshape = raid5_check_reshape, |
5356 | .start_reshape = raid5_start_reshape, | |
cea9c228 | 5357 | .finish_reshape = raid5_finish_reshape, |
2604b703 N |
5358 | .quiesce = raid5_quiesce, |
5359 | }; | |
5360 | ||
5361 | static int __init raid5_init(void) | |
5362 | { | |
16a53ecc | 5363 | register_md_personality(&raid6_personality); |
2604b703 N |
5364 | register_md_personality(&raid5_personality); |
5365 | register_md_personality(&raid4_personality); | |
5366 | return 0; | |
1da177e4 LT |
5367 | } |
5368 | ||
2604b703 | 5369 | static void raid5_exit(void) |
1da177e4 | 5370 | { |
16a53ecc | 5371 | unregister_md_personality(&raid6_personality); |
2604b703 N |
5372 | unregister_md_personality(&raid5_personality); |
5373 | unregister_md_personality(&raid4_personality); | |
1da177e4 LT |
5374 | } |
5375 | ||
5376 | module_init(raid5_init); | |
5377 | module_exit(raid5_exit); | |
5378 | MODULE_LICENSE("GPL"); | |
5379 | MODULE_ALIAS("md-personality-4"); /* RAID5 */ | |
d9d166c2 N |
5380 | MODULE_ALIAS("md-raid5"); |
5381 | MODULE_ALIAS("md-raid4"); | |
2604b703 N |
5382 | MODULE_ALIAS("md-level-5"); |
5383 | MODULE_ALIAS("md-level-4"); | |
16a53ecc N |
5384 | MODULE_ALIAS("md-personality-8"); /* RAID6 */ |
5385 | MODULE_ALIAS("md-raid6"); | |
5386 | MODULE_ALIAS("md-level-6"); | |
5387 | ||
5388 | /* This used to be two separate modules, they were: */ | |
5389 | MODULE_ALIAS("raid5"); | |
5390 | MODULE_ALIAS("raid6"); |