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 | ||
d710e138 | 302 | static void raid5_build_block(struct stripe_head *sh, int i); |
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 | |
b5663ba4 | 321 | sh->disks = previous ? conf->previous_raid_disks : conf->raid_disks; |
1da177e4 | 322 | sh->sector = sector; |
911d4ee8 | 323 | stripe_set_idx(sector, conf, previous, sh); |
1da177e4 LT |
324 | sh->state = 0; |
325 | ||
7ecaa1e6 N |
326 | |
327 | for (i = sh->disks; i--; ) { | |
1da177e4 LT |
328 | struct r5dev *dev = &sh->dev[i]; |
329 | ||
d84e0f10 | 330 | if (dev->toread || dev->read || dev->towrite || dev->written || |
1da177e4 | 331 | test_bit(R5_LOCKED, &dev->flags)) { |
d84e0f10 | 332 | printk(KERN_ERR "sector=%llx i=%d %p %p %p %p %d\n", |
1da177e4 | 333 | (unsigned long long)sh->sector, i, dev->toread, |
d84e0f10 | 334 | dev->read, dev->towrite, dev->written, |
1da177e4 LT |
335 | test_bit(R5_LOCKED, &dev->flags)); |
336 | BUG(); | |
337 | } | |
338 | dev->flags = 0; | |
339 | raid5_build_block(sh, i); | |
340 | } | |
341 | insert_hash(conf, sh); | |
342 | } | |
343 | ||
7ecaa1e6 | 344 | static struct stripe_head *__find_stripe(raid5_conf_t *conf, sector_t sector, int disks) |
1da177e4 LT |
345 | { |
346 | struct stripe_head *sh; | |
fccddba0 | 347 | struct hlist_node *hn; |
1da177e4 LT |
348 | |
349 | CHECK_DEVLOCK(); | |
45b4233c | 350 | pr_debug("__find_stripe, sector %llu\n", (unsigned long long)sector); |
fccddba0 | 351 | hlist_for_each_entry(sh, hn, stripe_hash(conf, sector), hash) |
7ecaa1e6 | 352 | if (sh->sector == sector && sh->disks == disks) |
1da177e4 | 353 | return sh; |
45b4233c | 354 | pr_debug("__stripe %llu not in cache\n", (unsigned long long)sector); |
1da177e4 LT |
355 | return NULL; |
356 | } | |
357 | ||
358 | static void unplug_slaves(mddev_t *mddev); | |
165125e1 | 359 | static void raid5_unplug_device(struct request_queue *q); |
1da177e4 | 360 | |
b5663ba4 N |
361 | static struct stripe_head * |
362 | get_active_stripe(raid5_conf_t *conf, sector_t sector, | |
363 | int previous, int noblock) | |
1da177e4 LT |
364 | { |
365 | struct stripe_head *sh; | |
b5663ba4 | 366 | int disks = previous ? conf->previous_raid_disks : conf->raid_disks; |
1da177e4 | 367 | |
45b4233c | 368 | pr_debug("get_stripe, sector %llu\n", (unsigned long long)sector); |
1da177e4 LT |
369 | |
370 | spin_lock_irq(&conf->device_lock); | |
371 | ||
372 | do { | |
72626685 N |
373 | wait_event_lock_irq(conf->wait_for_stripe, |
374 | conf->quiesce == 0, | |
375 | conf->device_lock, /* nothing */); | |
7ecaa1e6 | 376 | sh = __find_stripe(conf, sector, disks); |
1da177e4 LT |
377 | if (!sh) { |
378 | if (!conf->inactive_blocked) | |
379 | sh = get_free_stripe(conf); | |
380 | if (noblock && sh == NULL) | |
381 | break; | |
382 | if (!sh) { | |
383 | conf->inactive_blocked = 1; | |
384 | wait_event_lock_irq(conf->wait_for_stripe, | |
385 | !list_empty(&conf->inactive_list) && | |
5036805b N |
386 | (atomic_read(&conf->active_stripes) |
387 | < (conf->max_nr_stripes *3/4) | |
1da177e4 LT |
388 | || !conf->inactive_blocked), |
389 | conf->device_lock, | |
f4370781 | 390 | raid5_unplug_device(conf->mddev->queue) |
1da177e4 LT |
391 | ); |
392 | conf->inactive_blocked = 0; | |
393 | } else | |
b5663ba4 | 394 | init_stripe(sh, sector, previous); |
1da177e4 LT |
395 | } else { |
396 | if (atomic_read(&sh->count)) { | |
78bafebd | 397 | BUG_ON(!list_empty(&sh->lru)); |
1da177e4 LT |
398 | } else { |
399 | if (!test_bit(STRIPE_HANDLE, &sh->state)) | |
400 | atomic_inc(&conf->active_stripes); | |
ff4e8d9a N |
401 | if (list_empty(&sh->lru) && |
402 | !test_bit(STRIPE_EXPANDING, &sh->state)) | |
16a53ecc N |
403 | BUG(); |
404 | list_del_init(&sh->lru); | |
1da177e4 LT |
405 | } |
406 | } | |
407 | } while (sh == NULL); | |
408 | ||
409 | if (sh) | |
410 | atomic_inc(&sh->count); | |
411 | ||
412 | spin_unlock_irq(&conf->device_lock); | |
413 | return sh; | |
414 | } | |
415 | ||
6712ecf8 N |
416 | static void |
417 | raid5_end_read_request(struct bio *bi, int error); | |
418 | static void | |
419 | raid5_end_write_request(struct bio *bi, int error); | |
91c00924 | 420 | |
c4e5ac0a | 421 | static void ops_run_io(struct stripe_head *sh, struct stripe_head_state *s) |
91c00924 DW |
422 | { |
423 | raid5_conf_t *conf = sh->raid_conf; | |
424 | int i, disks = sh->disks; | |
425 | ||
426 | might_sleep(); | |
427 | ||
428 | for (i = disks; i--; ) { | |
429 | int rw; | |
430 | struct bio *bi; | |
431 | mdk_rdev_t *rdev; | |
432 | if (test_and_clear_bit(R5_Wantwrite, &sh->dev[i].flags)) | |
433 | rw = WRITE; | |
434 | else if (test_and_clear_bit(R5_Wantread, &sh->dev[i].flags)) | |
435 | rw = READ; | |
436 | else | |
437 | continue; | |
438 | ||
439 | bi = &sh->dev[i].req; | |
440 | ||
441 | bi->bi_rw = rw; | |
442 | if (rw == WRITE) | |
443 | bi->bi_end_io = raid5_end_write_request; | |
444 | else | |
445 | bi->bi_end_io = raid5_end_read_request; | |
446 | ||
447 | rcu_read_lock(); | |
448 | rdev = rcu_dereference(conf->disks[i].rdev); | |
449 | if (rdev && test_bit(Faulty, &rdev->flags)) | |
450 | rdev = NULL; | |
451 | if (rdev) | |
452 | atomic_inc(&rdev->nr_pending); | |
453 | rcu_read_unlock(); | |
454 | ||
455 | if (rdev) { | |
c4e5ac0a | 456 | if (s->syncing || s->expanding || s->expanded) |
91c00924 DW |
457 | md_sync_acct(rdev->bdev, STRIPE_SECTORS); |
458 | ||
2b7497f0 DW |
459 | set_bit(STRIPE_IO_STARTED, &sh->state); |
460 | ||
91c00924 DW |
461 | bi->bi_bdev = rdev->bdev; |
462 | pr_debug("%s: for %llu schedule op %ld on disc %d\n", | |
e46b272b | 463 | __func__, (unsigned long long)sh->sector, |
91c00924 DW |
464 | bi->bi_rw, i); |
465 | atomic_inc(&sh->count); | |
466 | bi->bi_sector = sh->sector + rdev->data_offset; | |
467 | bi->bi_flags = 1 << BIO_UPTODATE; | |
468 | bi->bi_vcnt = 1; | |
469 | bi->bi_max_vecs = 1; | |
470 | bi->bi_idx = 0; | |
471 | bi->bi_io_vec = &sh->dev[i].vec; | |
472 | bi->bi_io_vec[0].bv_len = STRIPE_SIZE; | |
473 | bi->bi_io_vec[0].bv_offset = 0; | |
474 | bi->bi_size = STRIPE_SIZE; | |
475 | bi->bi_next = NULL; | |
476 | if (rw == WRITE && | |
477 | test_bit(R5_ReWrite, &sh->dev[i].flags)) | |
478 | atomic_add(STRIPE_SECTORS, | |
479 | &rdev->corrected_errors); | |
480 | generic_make_request(bi); | |
481 | } else { | |
482 | if (rw == WRITE) | |
483 | set_bit(STRIPE_DEGRADED, &sh->state); | |
484 | pr_debug("skip op %ld on disc %d for sector %llu\n", | |
485 | bi->bi_rw, i, (unsigned long long)sh->sector); | |
486 | clear_bit(R5_LOCKED, &sh->dev[i].flags); | |
487 | set_bit(STRIPE_HANDLE, &sh->state); | |
488 | } | |
489 | } | |
490 | } | |
491 | ||
492 | static struct dma_async_tx_descriptor * | |
493 | async_copy_data(int frombio, struct bio *bio, struct page *page, | |
494 | sector_t sector, struct dma_async_tx_descriptor *tx) | |
495 | { | |
496 | struct bio_vec *bvl; | |
497 | struct page *bio_page; | |
498 | int i; | |
499 | int page_offset; | |
500 | ||
501 | if (bio->bi_sector >= sector) | |
502 | page_offset = (signed)(bio->bi_sector - sector) * 512; | |
503 | else | |
504 | page_offset = (signed)(sector - bio->bi_sector) * -512; | |
505 | bio_for_each_segment(bvl, bio, i) { | |
506 | int len = bio_iovec_idx(bio, i)->bv_len; | |
507 | int clen; | |
508 | int b_offset = 0; | |
509 | ||
510 | if (page_offset < 0) { | |
511 | b_offset = -page_offset; | |
512 | page_offset += b_offset; | |
513 | len -= b_offset; | |
514 | } | |
515 | ||
516 | if (len > 0 && page_offset + len > STRIPE_SIZE) | |
517 | clen = STRIPE_SIZE - page_offset; | |
518 | else | |
519 | clen = len; | |
520 | ||
521 | if (clen > 0) { | |
522 | b_offset += bio_iovec_idx(bio, i)->bv_offset; | |
523 | bio_page = bio_iovec_idx(bio, i)->bv_page; | |
524 | if (frombio) | |
525 | tx = async_memcpy(page, bio_page, page_offset, | |
526 | b_offset, clen, | |
eb0645a8 | 527 | ASYNC_TX_DEP_ACK, |
91c00924 DW |
528 | tx, NULL, NULL); |
529 | else | |
530 | tx = async_memcpy(bio_page, page, b_offset, | |
531 | page_offset, clen, | |
eb0645a8 | 532 | ASYNC_TX_DEP_ACK, |
91c00924 DW |
533 | tx, NULL, NULL); |
534 | } | |
535 | if (clen < len) /* hit end of page */ | |
536 | break; | |
537 | page_offset += len; | |
538 | } | |
539 | ||
540 | return tx; | |
541 | } | |
542 | ||
543 | static void ops_complete_biofill(void *stripe_head_ref) | |
544 | { | |
545 | struct stripe_head *sh = stripe_head_ref; | |
546 | struct bio *return_bi = NULL; | |
547 | raid5_conf_t *conf = sh->raid_conf; | |
e4d84909 | 548 | int i; |
91c00924 | 549 | |
e46b272b | 550 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
551 | (unsigned long long)sh->sector); |
552 | ||
553 | /* clear completed biofills */ | |
83de75cc | 554 | spin_lock_irq(&conf->device_lock); |
91c00924 DW |
555 | for (i = sh->disks; i--; ) { |
556 | struct r5dev *dev = &sh->dev[i]; | |
91c00924 DW |
557 | |
558 | /* acknowledge completion of a biofill operation */ | |
e4d84909 DW |
559 | /* and check if we need to reply to a read request, |
560 | * new R5_Wantfill requests are held off until | |
83de75cc | 561 | * !STRIPE_BIOFILL_RUN |
e4d84909 DW |
562 | */ |
563 | if (test_and_clear_bit(R5_Wantfill, &dev->flags)) { | |
91c00924 | 564 | struct bio *rbi, *rbi2; |
91c00924 | 565 | |
91c00924 DW |
566 | BUG_ON(!dev->read); |
567 | rbi = dev->read; | |
568 | dev->read = NULL; | |
569 | while (rbi && rbi->bi_sector < | |
570 | dev->sector + STRIPE_SECTORS) { | |
571 | rbi2 = r5_next_bio(rbi, dev->sector); | |
960e739d | 572 | if (!raid5_dec_bi_phys_segments(rbi)) { |
91c00924 DW |
573 | rbi->bi_next = return_bi; |
574 | return_bi = rbi; | |
575 | } | |
91c00924 DW |
576 | rbi = rbi2; |
577 | } | |
578 | } | |
579 | } | |
83de75cc DW |
580 | spin_unlock_irq(&conf->device_lock); |
581 | clear_bit(STRIPE_BIOFILL_RUN, &sh->state); | |
91c00924 DW |
582 | |
583 | return_io(return_bi); | |
584 | ||
e4d84909 | 585 | set_bit(STRIPE_HANDLE, &sh->state); |
91c00924 DW |
586 | release_stripe(sh); |
587 | } | |
588 | ||
589 | static void ops_run_biofill(struct stripe_head *sh) | |
590 | { | |
591 | struct dma_async_tx_descriptor *tx = NULL; | |
592 | raid5_conf_t *conf = sh->raid_conf; | |
593 | int i; | |
594 | ||
e46b272b | 595 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
596 | (unsigned long long)sh->sector); |
597 | ||
598 | for (i = sh->disks; i--; ) { | |
599 | struct r5dev *dev = &sh->dev[i]; | |
600 | if (test_bit(R5_Wantfill, &dev->flags)) { | |
601 | struct bio *rbi; | |
602 | spin_lock_irq(&conf->device_lock); | |
603 | dev->read = rbi = dev->toread; | |
604 | dev->toread = NULL; | |
605 | spin_unlock_irq(&conf->device_lock); | |
606 | while (rbi && rbi->bi_sector < | |
607 | dev->sector + STRIPE_SECTORS) { | |
608 | tx = async_copy_data(0, rbi, dev->page, | |
609 | dev->sector, tx); | |
610 | rbi = r5_next_bio(rbi, dev->sector); | |
611 | } | |
612 | } | |
613 | } | |
614 | ||
615 | atomic_inc(&sh->count); | |
616 | async_trigger_callback(ASYNC_TX_DEP_ACK | ASYNC_TX_ACK, tx, | |
617 | ops_complete_biofill, sh); | |
618 | } | |
619 | ||
620 | static void ops_complete_compute5(void *stripe_head_ref) | |
621 | { | |
622 | struct stripe_head *sh = stripe_head_ref; | |
623 | int target = sh->ops.target; | |
624 | struct r5dev *tgt = &sh->dev[target]; | |
625 | ||
e46b272b | 626 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
627 | (unsigned long long)sh->sector); |
628 | ||
629 | set_bit(R5_UPTODATE, &tgt->flags); | |
630 | BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags)); | |
631 | clear_bit(R5_Wantcompute, &tgt->flags); | |
ecc65c9b DW |
632 | clear_bit(STRIPE_COMPUTE_RUN, &sh->state); |
633 | if (sh->check_state == check_state_compute_run) | |
634 | sh->check_state = check_state_compute_result; | |
91c00924 DW |
635 | set_bit(STRIPE_HANDLE, &sh->state); |
636 | release_stripe(sh); | |
637 | } | |
638 | ||
7b3a871e | 639 | static struct dma_async_tx_descriptor *ops_run_compute5(struct stripe_head *sh) |
91c00924 DW |
640 | { |
641 | /* kernel stack size limits the total number of disks */ | |
642 | int disks = sh->disks; | |
643 | struct page *xor_srcs[disks]; | |
644 | int target = sh->ops.target; | |
645 | struct r5dev *tgt = &sh->dev[target]; | |
646 | struct page *xor_dest = tgt->page; | |
647 | int count = 0; | |
648 | struct dma_async_tx_descriptor *tx; | |
649 | int i; | |
650 | ||
651 | pr_debug("%s: stripe %llu block: %d\n", | |
e46b272b | 652 | __func__, (unsigned long long)sh->sector, target); |
91c00924 DW |
653 | BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags)); |
654 | ||
655 | for (i = disks; i--; ) | |
656 | if (i != target) | |
657 | xor_srcs[count++] = sh->dev[i].page; | |
658 | ||
659 | atomic_inc(&sh->count); | |
660 | ||
661 | if (unlikely(count == 1)) | |
662 | tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE, | |
663 | 0, NULL, ops_complete_compute5, sh); | |
664 | else | |
665 | tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, | |
666 | ASYNC_TX_XOR_ZERO_DST, NULL, | |
667 | ops_complete_compute5, sh); | |
668 | ||
91c00924 DW |
669 | return tx; |
670 | } | |
671 | ||
672 | static void ops_complete_prexor(void *stripe_head_ref) | |
673 | { | |
674 | struct stripe_head *sh = stripe_head_ref; | |
675 | ||
e46b272b | 676 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 | 677 | (unsigned long long)sh->sector); |
91c00924 DW |
678 | } |
679 | ||
680 | static struct dma_async_tx_descriptor * | |
681 | ops_run_prexor(struct stripe_head *sh, struct dma_async_tx_descriptor *tx) | |
682 | { | |
683 | /* kernel stack size limits the total number of disks */ | |
684 | int disks = sh->disks; | |
685 | struct page *xor_srcs[disks]; | |
686 | int count = 0, pd_idx = sh->pd_idx, i; | |
687 | ||
688 | /* existing parity data subtracted */ | |
689 | struct page *xor_dest = xor_srcs[count++] = sh->dev[pd_idx].page; | |
690 | ||
e46b272b | 691 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
692 | (unsigned long long)sh->sector); |
693 | ||
694 | for (i = disks; i--; ) { | |
695 | struct r5dev *dev = &sh->dev[i]; | |
696 | /* Only process blocks that are known to be uptodate */ | |
d8ee0728 | 697 | if (test_bit(R5_Wantdrain, &dev->flags)) |
91c00924 DW |
698 | xor_srcs[count++] = dev->page; |
699 | } | |
700 | ||
701 | tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, | |
702 | ASYNC_TX_DEP_ACK | ASYNC_TX_XOR_DROP_DST, tx, | |
703 | ops_complete_prexor, sh); | |
704 | ||
705 | return tx; | |
706 | } | |
707 | ||
708 | static struct dma_async_tx_descriptor * | |
d8ee0728 | 709 | ops_run_biodrain(struct stripe_head *sh, struct dma_async_tx_descriptor *tx) |
91c00924 DW |
710 | { |
711 | int disks = sh->disks; | |
d8ee0728 | 712 | int i; |
91c00924 | 713 | |
e46b272b | 714 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
715 | (unsigned long long)sh->sector); |
716 | ||
717 | for (i = disks; i--; ) { | |
718 | struct r5dev *dev = &sh->dev[i]; | |
719 | struct bio *chosen; | |
91c00924 | 720 | |
d8ee0728 | 721 | if (test_and_clear_bit(R5_Wantdrain, &dev->flags)) { |
91c00924 DW |
722 | struct bio *wbi; |
723 | ||
724 | spin_lock(&sh->lock); | |
725 | chosen = dev->towrite; | |
726 | dev->towrite = NULL; | |
727 | BUG_ON(dev->written); | |
728 | wbi = dev->written = chosen; | |
729 | spin_unlock(&sh->lock); | |
730 | ||
731 | while (wbi && wbi->bi_sector < | |
732 | dev->sector + STRIPE_SECTORS) { | |
733 | tx = async_copy_data(1, wbi, dev->page, | |
734 | dev->sector, tx); | |
735 | wbi = r5_next_bio(wbi, dev->sector); | |
736 | } | |
737 | } | |
738 | } | |
739 | ||
740 | return tx; | |
741 | } | |
742 | ||
743 | static void ops_complete_postxor(void *stripe_head_ref) | |
91c00924 DW |
744 | { |
745 | struct stripe_head *sh = stripe_head_ref; | |
746 | int disks = sh->disks, i, pd_idx = sh->pd_idx; | |
747 | ||
e46b272b | 748 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
749 | (unsigned long long)sh->sector); |
750 | ||
751 | for (i = disks; i--; ) { | |
752 | struct r5dev *dev = &sh->dev[i]; | |
753 | if (dev->written || i == pd_idx) | |
754 | set_bit(R5_UPTODATE, &dev->flags); | |
755 | } | |
756 | ||
d8ee0728 DW |
757 | if (sh->reconstruct_state == reconstruct_state_drain_run) |
758 | sh->reconstruct_state = reconstruct_state_drain_result; | |
759 | else if (sh->reconstruct_state == reconstruct_state_prexor_drain_run) | |
760 | sh->reconstruct_state = reconstruct_state_prexor_drain_result; | |
761 | else { | |
762 | BUG_ON(sh->reconstruct_state != reconstruct_state_run); | |
763 | sh->reconstruct_state = reconstruct_state_result; | |
764 | } | |
91c00924 DW |
765 | |
766 | set_bit(STRIPE_HANDLE, &sh->state); | |
767 | release_stripe(sh); | |
768 | } | |
769 | ||
770 | static void | |
d8ee0728 | 771 | ops_run_postxor(struct stripe_head *sh, struct dma_async_tx_descriptor *tx) |
91c00924 DW |
772 | { |
773 | /* kernel stack size limits the total number of disks */ | |
774 | int disks = sh->disks; | |
775 | struct page *xor_srcs[disks]; | |
776 | ||
777 | int count = 0, pd_idx = sh->pd_idx, i; | |
778 | struct page *xor_dest; | |
d8ee0728 | 779 | int prexor = 0; |
91c00924 | 780 | unsigned long flags; |
91c00924 | 781 | |
e46b272b | 782 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
783 | (unsigned long long)sh->sector); |
784 | ||
785 | /* check if prexor is active which means only process blocks | |
786 | * that are part of a read-modify-write (written) | |
787 | */ | |
d8ee0728 DW |
788 | if (sh->reconstruct_state == reconstruct_state_prexor_drain_run) { |
789 | prexor = 1; | |
91c00924 DW |
790 | xor_dest = xor_srcs[count++] = sh->dev[pd_idx].page; |
791 | for (i = disks; i--; ) { | |
792 | struct r5dev *dev = &sh->dev[i]; | |
793 | if (dev->written) | |
794 | xor_srcs[count++] = dev->page; | |
795 | } | |
796 | } else { | |
797 | xor_dest = sh->dev[pd_idx].page; | |
798 | for (i = disks; i--; ) { | |
799 | struct r5dev *dev = &sh->dev[i]; | |
800 | if (i != pd_idx) | |
801 | xor_srcs[count++] = dev->page; | |
802 | } | |
803 | } | |
804 | ||
91c00924 DW |
805 | /* 1/ if we prexor'd then the dest is reused as a source |
806 | * 2/ if we did not prexor then we are redoing the parity | |
807 | * set ASYNC_TX_XOR_DROP_DST and ASYNC_TX_XOR_ZERO_DST | |
808 | * for the synchronous xor case | |
809 | */ | |
810 | flags = ASYNC_TX_DEP_ACK | ASYNC_TX_ACK | | |
811 | (prexor ? ASYNC_TX_XOR_DROP_DST : ASYNC_TX_XOR_ZERO_DST); | |
812 | ||
813 | atomic_inc(&sh->count); | |
814 | ||
815 | if (unlikely(count == 1)) { | |
816 | flags &= ~(ASYNC_TX_XOR_DROP_DST | ASYNC_TX_XOR_ZERO_DST); | |
817 | tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE, | |
d8ee0728 | 818 | flags, tx, ops_complete_postxor, sh); |
91c00924 DW |
819 | } else |
820 | tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, | |
d8ee0728 | 821 | flags, tx, ops_complete_postxor, sh); |
91c00924 DW |
822 | } |
823 | ||
824 | static void ops_complete_check(void *stripe_head_ref) | |
825 | { | |
826 | struct stripe_head *sh = stripe_head_ref; | |
91c00924 | 827 | |
e46b272b | 828 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
829 | (unsigned long long)sh->sector); |
830 | ||
ecc65c9b | 831 | sh->check_state = check_state_check_result; |
91c00924 DW |
832 | set_bit(STRIPE_HANDLE, &sh->state); |
833 | release_stripe(sh); | |
834 | } | |
835 | ||
836 | static void ops_run_check(struct stripe_head *sh) | |
837 | { | |
838 | /* kernel stack size limits the total number of disks */ | |
839 | int disks = sh->disks; | |
840 | struct page *xor_srcs[disks]; | |
841 | struct dma_async_tx_descriptor *tx; | |
842 | ||
843 | int count = 0, pd_idx = sh->pd_idx, i; | |
844 | struct page *xor_dest = xor_srcs[count++] = sh->dev[pd_idx].page; | |
845 | ||
e46b272b | 846 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
847 | (unsigned long long)sh->sector); |
848 | ||
849 | for (i = disks; i--; ) { | |
850 | struct r5dev *dev = &sh->dev[i]; | |
851 | if (i != pd_idx) | |
852 | xor_srcs[count++] = dev->page; | |
853 | } | |
854 | ||
855 | tx = async_xor_zero_sum(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, | |
856 | &sh->ops.zero_sum_result, 0, NULL, NULL, NULL); | |
857 | ||
91c00924 DW |
858 | atomic_inc(&sh->count); |
859 | tx = async_trigger_callback(ASYNC_TX_DEP_ACK | ASYNC_TX_ACK, tx, | |
860 | ops_complete_check, sh); | |
861 | } | |
862 | ||
600aa109 | 863 | static void raid5_run_ops(struct stripe_head *sh, unsigned long ops_request) |
91c00924 DW |
864 | { |
865 | int overlap_clear = 0, i, disks = sh->disks; | |
866 | struct dma_async_tx_descriptor *tx = NULL; | |
867 | ||
83de75cc | 868 | if (test_bit(STRIPE_OP_BIOFILL, &ops_request)) { |
91c00924 DW |
869 | ops_run_biofill(sh); |
870 | overlap_clear++; | |
871 | } | |
872 | ||
7b3a871e DW |
873 | if (test_bit(STRIPE_OP_COMPUTE_BLK, &ops_request)) { |
874 | tx = ops_run_compute5(sh); | |
875 | /* terminate the chain if postxor is not set to be run */ | |
876 | if (tx && !test_bit(STRIPE_OP_POSTXOR, &ops_request)) | |
877 | async_tx_ack(tx); | |
878 | } | |
91c00924 | 879 | |
600aa109 | 880 | if (test_bit(STRIPE_OP_PREXOR, &ops_request)) |
91c00924 DW |
881 | tx = ops_run_prexor(sh, tx); |
882 | ||
600aa109 | 883 | if (test_bit(STRIPE_OP_BIODRAIN, &ops_request)) { |
d8ee0728 | 884 | tx = ops_run_biodrain(sh, tx); |
91c00924 DW |
885 | overlap_clear++; |
886 | } | |
887 | ||
600aa109 | 888 | if (test_bit(STRIPE_OP_POSTXOR, &ops_request)) |
d8ee0728 | 889 | ops_run_postxor(sh, tx); |
91c00924 | 890 | |
ecc65c9b | 891 | if (test_bit(STRIPE_OP_CHECK, &ops_request)) |
91c00924 DW |
892 | ops_run_check(sh); |
893 | ||
91c00924 DW |
894 | if (overlap_clear) |
895 | for (i = disks; i--; ) { | |
896 | struct r5dev *dev = &sh->dev[i]; | |
897 | if (test_and_clear_bit(R5_Overlap, &dev->flags)) | |
898 | wake_up(&sh->raid_conf->wait_for_overlap); | |
899 | } | |
900 | } | |
901 | ||
3f294f4f | 902 | static int grow_one_stripe(raid5_conf_t *conf) |
1da177e4 LT |
903 | { |
904 | struct stripe_head *sh; | |
3f294f4f N |
905 | sh = kmem_cache_alloc(conf->slab_cache, GFP_KERNEL); |
906 | if (!sh) | |
907 | return 0; | |
908 | memset(sh, 0, sizeof(*sh) + (conf->raid_disks-1)*sizeof(struct r5dev)); | |
909 | sh->raid_conf = conf; | |
910 | spin_lock_init(&sh->lock); | |
911 | ||
912 | if (grow_buffers(sh, conf->raid_disks)) { | |
913 | shrink_buffers(sh, conf->raid_disks); | |
914 | kmem_cache_free(conf->slab_cache, sh); | |
915 | return 0; | |
916 | } | |
7ecaa1e6 | 917 | sh->disks = conf->raid_disks; |
3f294f4f N |
918 | /* we just created an active stripe so... */ |
919 | atomic_set(&sh->count, 1); | |
920 | atomic_inc(&conf->active_stripes); | |
921 | INIT_LIST_HEAD(&sh->lru); | |
922 | release_stripe(sh); | |
923 | return 1; | |
924 | } | |
925 | ||
926 | static int grow_stripes(raid5_conf_t *conf, int num) | |
927 | { | |
e18b890b | 928 | struct kmem_cache *sc; |
1da177e4 LT |
929 | int devs = conf->raid_disks; |
930 | ||
245f46c2 N |
931 | sprintf(conf->cache_name[0], |
932 | "raid%d-%s", conf->level, mdname(conf->mddev)); | |
933 | sprintf(conf->cache_name[1], | |
934 | "raid%d-%s-alt", conf->level, mdname(conf->mddev)); | |
ad01c9e3 N |
935 | conf->active_name = 0; |
936 | sc = kmem_cache_create(conf->cache_name[conf->active_name], | |
1da177e4 | 937 | sizeof(struct stripe_head)+(devs-1)*sizeof(struct r5dev), |
20c2df83 | 938 | 0, 0, NULL); |
1da177e4 LT |
939 | if (!sc) |
940 | return 1; | |
941 | conf->slab_cache = sc; | |
ad01c9e3 | 942 | conf->pool_size = devs; |
16a53ecc | 943 | while (num--) |
3f294f4f | 944 | if (!grow_one_stripe(conf)) |
1da177e4 | 945 | return 1; |
1da177e4 LT |
946 | return 0; |
947 | } | |
29269553 N |
948 | |
949 | #ifdef CONFIG_MD_RAID5_RESHAPE | |
ad01c9e3 N |
950 | static int resize_stripes(raid5_conf_t *conf, int newsize) |
951 | { | |
952 | /* Make all the stripes able to hold 'newsize' devices. | |
953 | * New slots in each stripe get 'page' set to a new page. | |
954 | * | |
955 | * This happens in stages: | |
956 | * 1/ create a new kmem_cache and allocate the required number of | |
957 | * stripe_heads. | |
958 | * 2/ gather all the old stripe_heads and tranfer the pages across | |
959 | * to the new stripe_heads. This will have the side effect of | |
960 | * freezing the array as once all stripe_heads have been collected, | |
961 | * no IO will be possible. Old stripe heads are freed once their | |
962 | * pages have been transferred over, and the old kmem_cache is | |
963 | * freed when all stripes are done. | |
964 | * 3/ reallocate conf->disks to be suitable bigger. If this fails, | |
965 | * we simple return a failre status - no need to clean anything up. | |
966 | * 4/ allocate new pages for the new slots in the new stripe_heads. | |
967 | * If this fails, we don't bother trying the shrink the | |
968 | * stripe_heads down again, we just leave them as they are. | |
969 | * As each stripe_head is processed the new one is released into | |
970 | * active service. | |
971 | * | |
972 | * Once step2 is started, we cannot afford to wait for a write, | |
973 | * so we use GFP_NOIO allocations. | |
974 | */ | |
975 | struct stripe_head *osh, *nsh; | |
976 | LIST_HEAD(newstripes); | |
977 | struct disk_info *ndisks; | |
b5470dc5 | 978 | int err; |
e18b890b | 979 | struct kmem_cache *sc; |
ad01c9e3 N |
980 | int i; |
981 | ||
982 | if (newsize <= conf->pool_size) | |
983 | return 0; /* never bother to shrink */ | |
984 | ||
b5470dc5 DW |
985 | err = md_allow_write(conf->mddev); |
986 | if (err) | |
987 | return err; | |
2a2275d6 | 988 | |
ad01c9e3 N |
989 | /* Step 1 */ |
990 | sc = kmem_cache_create(conf->cache_name[1-conf->active_name], | |
991 | sizeof(struct stripe_head)+(newsize-1)*sizeof(struct r5dev), | |
20c2df83 | 992 | 0, 0, NULL); |
ad01c9e3 N |
993 | if (!sc) |
994 | return -ENOMEM; | |
995 | ||
996 | for (i = conf->max_nr_stripes; i; i--) { | |
997 | nsh = kmem_cache_alloc(sc, GFP_KERNEL); | |
998 | if (!nsh) | |
999 | break; | |
1000 | ||
1001 | memset(nsh, 0, sizeof(*nsh) + (newsize-1)*sizeof(struct r5dev)); | |
1002 | ||
1003 | nsh->raid_conf = conf; | |
1004 | spin_lock_init(&nsh->lock); | |
1005 | ||
1006 | list_add(&nsh->lru, &newstripes); | |
1007 | } | |
1008 | if (i) { | |
1009 | /* didn't get enough, give up */ | |
1010 | while (!list_empty(&newstripes)) { | |
1011 | nsh = list_entry(newstripes.next, struct stripe_head, lru); | |
1012 | list_del(&nsh->lru); | |
1013 | kmem_cache_free(sc, nsh); | |
1014 | } | |
1015 | kmem_cache_destroy(sc); | |
1016 | return -ENOMEM; | |
1017 | } | |
1018 | /* Step 2 - Must use GFP_NOIO now. | |
1019 | * OK, we have enough stripes, start collecting inactive | |
1020 | * stripes and copying them over | |
1021 | */ | |
1022 | list_for_each_entry(nsh, &newstripes, lru) { | |
1023 | spin_lock_irq(&conf->device_lock); | |
1024 | wait_event_lock_irq(conf->wait_for_stripe, | |
1025 | !list_empty(&conf->inactive_list), | |
1026 | conf->device_lock, | |
b3b46be3 | 1027 | unplug_slaves(conf->mddev) |
ad01c9e3 N |
1028 | ); |
1029 | osh = get_free_stripe(conf); | |
1030 | spin_unlock_irq(&conf->device_lock); | |
1031 | atomic_set(&nsh->count, 1); | |
1032 | for(i=0; i<conf->pool_size; i++) | |
1033 | nsh->dev[i].page = osh->dev[i].page; | |
1034 | for( ; i<newsize; i++) | |
1035 | nsh->dev[i].page = NULL; | |
1036 | kmem_cache_free(conf->slab_cache, osh); | |
1037 | } | |
1038 | kmem_cache_destroy(conf->slab_cache); | |
1039 | ||
1040 | /* Step 3. | |
1041 | * At this point, we are holding all the stripes so the array | |
1042 | * is completely stalled, so now is a good time to resize | |
1043 | * conf->disks. | |
1044 | */ | |
1045 | ndisks = kzalloc(newsize * sizeof(struct disk_info), GFP_NOIO); | |
1046 | if (ndisks) { | |
1047 | for (i=0; i<conf->raid_disks; i++) | |
1048 | ndisks[i] = conf->disks[i]; | |
1049 | kfree(conf->disks); | |
1050 | conf->disks = ndisks; | |
1051 | } else | |
1052 | err = -ENOMEM; | |
1053 | ||
1054 | /* Step 4, return new stripes to service */ | |
1055 | while(!list_empty(&newstripes)) { | |
1056 | nsh = list_entry(newstripes.next, struct stripe_head, lru); | |
1057 | list_del_init(&nsh->lru); | |
1058 | for (i=conf->raid_disks; i < newsize; i++) | |
1059 | if (nsh->dev[i].page == NULL) { | |
1060 | struct page *p = alloc_page(GFP_NOIO); | |
1061 | nsh->dev[i].page = p; | |
1062 | if (!p) | |
1063 | err = -ENOMEM; | |
1064 | } | |
1065 | release_stripe(nsh); | |
1066 | } | |
1067 | /* critical section pass, GFP_NOIO no longer needed */ | |
1068 | ||
1069 | conf->slab_cache = sc; | |
1070 | conf->active_name = 1-conf->active_name; | |
1071 | conf->pool_size = newsize; | |
1072 | return err; | |
1073 | } | |
29269553 | 1074 | #endif |
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 | ||
1214 | static sector_t compute_blocknr(struct stripe_head *sh, int i); | |
1215 | ||
d710e138 | 1216 | static void raid5_build_block(struct stripe_head *sh, int i) |
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; | |
16a53ecc | 1232 | dev->sector = compute_blocknr(sh, i); |
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 LT |
1274 | sector_t new_sector; |
1275 | int sectors_per_chunk = conf->chunk_size >> 9; | |
112bf897 N |
1276 | int raid_disks = previous ? conf->previous_raid_disks |
1277 | : conf->raid_disks; | |
1278 | int data_disks = raid_disks - conf->max_degraded; | |
1da177e4 LT |
1279 | |
1280 | /* First compute the information on this sector */ | |
1281 | ||
1282 | /* | |
1283 | * Compute the chunk number and the sector offset inside the chunk | |
1284 | */ | |
1285 | chunk_offset = sector_div(r_sector, sectors_per_chunk); | |
1286 | chunk_number = r_sector; | |
1287 | BUG_ON(r_sector != chunk_number); | |
1288 | ||
1289 | /* | |
1290 | * Compute the stripe number | |
1291 | */ | |
1292 | stripe = chunk_number / data_disks; | |
1293 | ||
1294 | /* | |
1295 | * Compute the data disk and parity disk indexes inside the stripe | |
1296 | */ | |
1297 | *dd_idx = chunk_number % data_disks; | |
1298 | ||
1299 | /* | |
1300 | * Select the parity disk based on the user selected algorithm. | |
1301 | */ | |
911d4ee8 | 1302 | pd_idx = qd_idx = ~0; |
16a53ecc N |
1303 | switch(conf->level) { |
1304 | case 4: | |
911d4ee8 | 1305 | pd_idx = data_disks; |
16a53ecc N |
1306 | break; |
1307 | case 5: | |
1308 | switch (conf->algorithm) { | |
1da177e4 | 1309 | case ALGORITHM_LEFT_ASYMMETRIC: |
911d4ee8 N |
1310 | pd_idx = data_disks - stripe % raid_disks; |
1311 | if (*dd_idx >= pd_idx) | |
1da177e4 LT |
1312 | (*dd_idx)++; |
1313 | break; | |
1314 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
911d4ee8 N |
1315 | pd_idx = stripe % raid_disks; |
1316 | if (*dd_idx >= pd_idx) | |
1da177e4 LT |
1317 | (*dd_idx)++; |
1318 | break; | |
1319 | case ALGORITHM_LEFT_SYMMETRIC: | |
911d4ee8 N |
1320 | pd_idx = data_disks - stripe % raid_disks; |
1321 | *dd_idx = (pd_idx + 1 + *dd_idx) % raid_disks; | |
1da177e4 LT |
1322 | break; |
1323 | case ALGORITHM_RIGHT_SYMMETRIC: | |
911d4ee8 N |
1324 | pd_idx = stripe % raid_disks; |
1325 | *dd_idx = (pd_idx + 1 + *dd_idx) % raid_disks; | |
1da177e4 | 1326 | break; |
99c0fb5f N |
1327 | case ALGORITHM_PARITY_0: |
1328 | pd_idx = 0; | |
1329 | (*dd_idx)++; | |
1330 | break; | |
1331 | case ALGORITHM_PARITY_N: | |
1332 | pd_idx = data_disks; | |
1333 | break; | |
1da177e4 | 1334 | default: |
14f8d26b | 1335 | printk(KERN_ERR "raid5: unsupported algorithm %d\n", |
1da177e4 | 1336 | conf->algorithm); |
99c0fb5f | 1337 | BUG(); |
16a53ecc N |
1338 | } |
1339 | break; | |
1340 | case 6: | |
1341 | ||
16a53ecc N |
1342 | switch (conf->algorithm) { |
1343 | case ALGORITHM_LEFT_ASYMMETRIC: | |
911d4ee8 N |
1344 | pd_idx = raid_disks - 1 - (stripe % raid_disks); |
1345 | qd_idx = pd_idx + 1; | |
1346 | if (pd_idx == raid_disks-1) { | |
99c0fb5f | 1347 | (*dd_idx)++; /* Q D D D P */ |
911d4ee8 N |
1348 | qd_idx = 0; |
1349 | } else if (*dd_idx >= pd_idx) | |
16a53ecc N |
1350 | (*dd_idx) += 2; /* D D P Q D */ |
1351 | break; | |
1352 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
911d4ee8 N |
1353 | pd_idx = stripe % raid_disks; |
1354 | qd_idx = pd_idx + 1; | |
1355 | if (pd_idx == raid_disks-1) { | |
99c0fb5f | 1356 | (*dd_idx)++; /* Q D D D P */ |
911d4ee8 N |
1357 | qd_idx = 0; |
1358 | } else if (*dd_idx >= pd_idx) | |
16a53ecc N |
1359 | (*dd_idx) += 2; /* D D P Q D */ |
1360 | break; | |
1361 | case ALGORITHM_LEFT_SYMMETRIC: | |
911d4ee8 N |
1362 | pd_idx = raid_disks - 1 - (stripe % raid_disks); |
1363 | qd_idx = (pd_idx + 1) % raid_disks; | |
1364 | *dd_idx = (pd_idx + 2 + *dd_idx) % raid_disks; | |
16a53ecc N |
1365 | break; |
1366 | case ALGORITHM_RIGHT_SYMMETRIC: | |
911d4ee8 N |
1367 | pd_idx = stripe % raid_disks; |
1368 | qd_idx = (pd_idx + 1) % raid_disks; | |
1369 | *dd_idx = (pd_idx + 2 + *dd_idx) % raid_disks; | |
16a53ecc | 1370 | break; |
99c0fb5f N |
1371 | |
1372 | case ALGORITHM_PARITY_0: | |
1373 | pd_idx = 0; | |
1374 | qd_idx = 1; | |
1375 | (*dd_idx) += 2; | |
1376 | break; | |
1377 | case ALGORITHM_PARITY_N: | |
1378 | pd_idx = data_disks; | |
1379 | qd_idx = data_disks + 1; | |
1380 | break; | |
1381 | ||
1382 | case ALGORITHM_ROTATING_ZERO_RESTART: | |
1383 | /* Exactly the same as RIGHT_ASYMMETRIC, but or | |
1384 | * of blocks for computing Q is different. | |
1385 | */ | |
1386 | pd_idx = stripe % raid_disks; | |
1387 | qd_idx = pd_idx + 1; | |
1388 | if (pd_idx == raid_disks-1) { | |
1389 | (*dd_idx)++; /* Q D D D P */ | |
1390 | qd_idx = 0; | |
1391 | } else if (*dd_idx >= pd_idx) | |
1392 | (*dd_idx) += 2; /* D D P Q D */ | |
67cc2b81 | 1393 | ddf_layout = 1; |
99c0fb5f N |
1394 | break; |
1395 | ||
1396 | case ALGORITHM_ROTATING_N_RESTART: | |
1397 | /* Same a left_asymmetric, by first stripe is | |
1398 | * D D D P Q rather than | |
1399 | * Q D D D P | |
1400 | */ | |
1401 | pd_idx = raid_disks - 1 - ((stripe + 1) % raid_disks); | |
1402 | qd_idx = pd_idx + 1; | |
1403 | if (pd_idx == raid_disks-1) { | |
1404 | (*dd_idx)++; /* Q D D D P */ | |
1405 | qd_idx = 0; | |
1406 | } else if (*dd_idx >= pd_idx) | |
1407 | (*dd_idx) += 2; /* D D P Q D */ | |
67cc2b81 | 1408 | ddf_layout = 1; |
99c0fb5f N |
1409 | break; |
1410 | ||
1411 | case ALGORITHM_ROTATING_N_CONTINUE: | |
1412 | /* Same as left_symmetric but Q is before P */ | |
1413 | pd_idx = raid_disks - 1 - (stripe % raid_disks); | |
1414 | qd_idx = (pd_idx + raid_disks - 1) % raid_disks; | |
1415 | *dd_idx = (pd_idx + 1 + *dd_idx) % raid_disks; | |
67cc2b81 | 1416 | ddf_layout = 1; |
99c0fb5f N |
1417 | break; |
1418 | ||
1419 | case ALGORITHM_LEFT_ASYMMETRIC_6: | |
1420 | /* RAID5 left_asymmetric, with Q on last device */ | |
1421 | pd_idx = data_disks - stripe % (raid_disks-1); | |
1422 | if (*dd_idx >= pd_idx) | |
1423 | (*dd_idx)++; | |
1424 | qd_idx = raid_disks - 1; | |
1425 | break; | |
1426 | ||
1427 | case ALGORITHM_RIGHT_ASYMMETRIC_6: | |
1428 | pd_idx = stripe % (raid_disks-1); | |
1429 | if (*dd_idx >= pd_idx) | |
1430 | (*dd_idx)++; | |
1431 | qd_idx = raid_disks - 1; | |
1432 | break; | |
1433 | ||
1434 | case ALGORITHM_LEFT_SYMMETRIC_6: | |
1435 | pd_idx = data_disks - stripe % (raid_disks-1); | |
1436 | *dd_idx = (pd_idx + 1 + *dd_idx) % (raid_disks-1); | |
1437 | qd_idx = raid_disks - 1; | |
1438 | break; | |
1439 | ||
1440 | case ALGORITHM_RIGHT_SYMMETRIC_6: | |
1441 | pd_idx = stripe % (raid_disks-1); | |
1442 | *dd_idx = (pd_idx + 1 + *dd_idx) % (raid_disks-1); | |
1443 | qd_idx = raid_disks - 1; | |
1444 | break; | |
1445 | ||
1446 | case ALGORITHM_PARITY_0_6: | |
1447 | pd_idx = 0; | |
1448 | (*dd_idx)++; | |
1449 | qd_idx = raid_disks - 1; | |
1450 | break; | |
1451 | ||
1452 | ||
16a53ecc | 1453 | default: |
d710e138 N |
1454 | printk(KERN_CRIT "raid6: unsupported algorithm %d\n", |
1455 | conf->algorithm); | |
99c0fb5f | 1456 | BUG(); |
16a53ecc N |
1457 | } |
1458 | break; | |
1da177e4 LT |
1459 | } |
1460 | ||
911d4ee8 N |
1461 | if (sh) { |
1462 | sh->pd_idx = pd_idx; | |
1463 | sh->qd_idx = qd_idx; | |
67cc2b81 | 1464 | sh->ddf_layout = ddf_layout; |
911d4ee8 | 1465 | } |
1da177e4 LT |
1466 | /* |
1467 | * Finally, compute the new sector number | |
1468 | */ | |
1469 | new_sector = (sector_t)stripe * sectors_per_chunk + chunk_offset; | |
1470 | return new_sector; | |
1471 | } | |
1472 | ||
1473 | ||
1474 | static sector_t compute_blocknr(struct stripe_head *sh, int i) | |
1475 | { | |
1476 | raid5_conf_t *conf = sh->raid_conf; | |
b875e531 N |
1477 | int raid_disks = sh->disks; |
1478 | int data_disks = raid_disks - conf->max_degraded; | |
1da177e4 LT |
1479 | sector_t new_sector = sh->sector, check; |
1480 | int sectors_per_chunk = conf->chunk_size >> 9; | |
1481 | sector_t stripe; | |
1482 | int chunk_offset; | |
911d4ee8 | 1483 | int chunk_number, dummy1, dd_idx = i; |
1da177e4 | 1484 | sector_t r_sector; |
911d4ee8 | 1485 | struct stripe_head sh2; |
1da177e4 | 1486 | |
16a53ecc | 1487 | |
1da177e4 LT |
1488 | chunk_offset = sector_div(new_sector, sectors_per_chunk); |
1489 | stripe = new_sector; | |
1490 | BUG_ON(new_sector != stripe); | |
1491 | ||
16a53ecc N |
1492 | if (i == sh->pd_idx) |
1493 | return 0; | |
1494 | switch(conf->level) { | |
1495 | case 4: break; | |
1496 | case 5: | |
1497 | switch (conf->algorithm) { | |
1da177e4 LT |
1498 | case ALGORITHM_LEFT_ASYMMETRIC: |
1499 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
1500 | if (i > sh->pd_idx) | |
1501 | i--; | |
1502 | break; | |
1503 | case ALGORITHM_LEFT_SYMMETRIC: | |
1504 | case ALGORITHM_RIGHT_SYMMETRIC: | |
1505 | if (i < sh->pd_idx) | |
1506 | i += raid_disks; | |
1507 | i -= (sh->pd_idx + 1); | |
1508 | break; | |
99c0fb5f N |
1509 | case ALGORITHM_PARITY_0: |
1510 | i -= 1; | |
1511 | break; | |
1512 | case ALGORITHM_PARITY_N: | |
1513 | break; | |
1da177e4 | 1514 | default: |
14f8d26b | 1515 | printk(KERN_ERR "raid5: unsupported algorithm %d\n", |
16a53ecc | 1516 | conf->algorithm); |
99c0fb5f | 1517 | BUG(); |
16a53ecc N |
1518 | } |
1519 | break; | |
1520 | case 6: | |
d0dabf7e | 1521 | if (i == sh->qd_idx) |
16a53ecc N |
1522 | return 0; /* It is the Q disk */ |
1523 | switch (conf->algorithm) { | |
1524 | case ALGORITHM_LEFT_ASYMMETRIC: | |
1525 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
99c0fb5f N |
1526 | case ALGORITHM_ROTATING_ZERO_RESTART: |
1527 | case ALGORITHM_ROTATING_N_RESTART: | |
1528 | if (sh->pd_idx == raid_disks-1) | |
1529 | i--; /* Q D D D P */ | |
16a53ecc N |
1530 | else if (i > sh->pd_idx) |
1531 | i -= 2; /* D D P Q D */ | |
1532 | break; | |
1533 | case ALGORITHM_LEFT_SYMMETRIC: | |
1534 | case ALGORITHM_RIGHT_SYMMETRIC: | |
1535 | if (sh->pd_idx == raid_disks-1) | |
1536 | i--; /* Q D D D P */ | |
1537 | else { | |
1538 | /* D D P Q D */ | |
1539 | if (i < sh->pd_idx) | |
1540 | i += raid_disks; | |
1541 | i -= (sh->pd_idx + 2); | |
1542 | } | |
1543 | break; | |
99c0fb5f N |
1544 | case ALGORITHM_PARITY_0: |
1545 | i -= 2; | |
1546 | break; | |
1547 | case ALGORITHM_PARITY_N: | |
1548 | break; | |
1549 | case ALGORITHM_ROTATING_N_CONTINUE: | |
1550 | if (sh->pd_idx == 0) | |
1551 | i--; /* P D D D Q */ | |
1552 | else if (i > sh->pd_idx) | |
1553 | i -= 2; /* D D Q P D */ | |
1554 | break; | |
1555 | case ALGORITHM_LEFT_ASYMMETRIC_6: | |
1556 | case ALGORITHM_RIGHT_ASYMMETRIC_6: | |
1557 | if (i > sh->pd_idx) | |
1558 | i--; | |
1559 | break; | |
1560 | case ALGORITHM_LEFT_SYMMETRIC_6: | |
1561 | case ALGORITHM_RIGHT_SYMMETRIC_6: | |
1562 | if (i < sh->pd_idx) | |
1563 | i += data_disks + 1; | |
1564 | i -= (sh->pd_idx + 1); | |
1565 | break; | |
1566 | case ALGORITHM_PARITY_0_6: | |
1567 | i -= 1; | |
1568 | break; | |
16a53ecc | 1569 | default: |
d710e138 N |
1570 | printk(KERN_CRIT "raid6: unsupported algorithm %d\n", |
1571 | conf->algorithm); | |
99c0fb5f | 1572 | BUG(); |
16a53ecc N |
1573 | } |
1574 | break; | |
1da177e4 LT |
1575 | } |
1576 | ||
1577 | chunk_number = stripe * data_disks + i; | |
1578 | r_sector = (sector_t)chunk_number * sectors_per_chunk + chunk_offset; | |
1579 | ||
112bf897 N |
1580 | check = raid5_compute_sector(conf, r_sector, |
1581 | (raid_disks != conf->raid_disks), | |
911d4ee8 N |
1582 | &dummy1, &sh2); |
1583 | if (check != sh->sector || dummy1 != dd_idx || sh2.pd_idx != sh->pd_idx | |
1584 | || sh2.qd_idx != sh->qd_idx) { | |
14f8d26b | 1585 | printk(KERN_ERR "compute_blocknr: map not correct\n"); |
1da177e4 LT |
1586 | return 0; |
1587 | } | |
1588 | return r_sector; | |
1589 | } | |
1590 | ||
1591 | ||
1592 | ||
1593 | /* | |
16a53ecc N |
1594 | * Copy data between a page in the stripe cache, and one or more bion |
1595 | * The page could align with the middle of the bio, or there could be | |
1596 | * several bion, each with several bio_vecs, which cover part of the page | |
1597 | * Multiple bion are linked together on bi_next. There may be extras | |
1598 | * at the end of this list. We ignore them. | |
1da177e4 LT |
1599 | */ |
1600 | static void copy_data(int frombio, struct bio *bio, | |
1601 | struct page *page, | |
1602 | sector_t sector) | |
1603 | { | |
1604 | char *pa = page_address(page); | |
1605 | struct bio_vec *bvl; | |
1606 | int i; | |
1607 | int page_offset; | |
1608 | ||
1609 | if (bio->bi_sector >= sector) | |
1610 | page_offset = (signed)(bio->bi_sector - sector) * 512; | |
1611 | else | |
1612 | page_offset = (signed)(sector - bio->bi_sector) * -512; | |
1613 | bio_for_each_segment(bvl, bio, i) { | |
1614 | int len = bio_iovec_idx(bio,i)->bv_len; | |
1615 | int clen; | |
1616 | int b_offset = 0; | |
1617 | ||
1618 | if (page_offset < 0) { | |
1619 | b_offset = -page_offset; | |
1620 | page_offset += b_offset; | |
1621 | len -= b_offset; | |
1622 | } | |
1623 | ||
1624 | if (len > 0 && page_offset + len > STRIPE_SIZE) | |
1625 | clen = STRIPE_SIZE - page_offset; | |
1626 | else clen = len; | |
16a53ecc | 1627 | |
1da177e4 LT |
1628 | if (clen > 0) { |
1629 | char *ba = __bio_kmap_atomic(bio, i, KM_USER0); | |
1630 | if (frombio) | |
1631 | memcpy(pa+page_offset, ba+b_offset, clen); | |
1632 | else | |
1633 | memcpy(ba+b_offset, pa+page_offset, clen); | |
1634 | __bio_kunmap_atomic(ba, KM_USER0); | |
1635 | } | |
1636 | if (clen < len) /* hit end of page */ | |
1637 | break; | |
1638 | page_offset += len; | |
1639 | } | |
1640 | } | |
1641 | ||
9bc89cd8 DW |
1642 | #define check_xor() do { \ |
1643 | if (count == MAX_XOR_BLOCKS) { \ | |
1644 | xor_blocks(count, STRIPE_SIZE, dest, ptr);\ | |
1645 | count = 0; \ | |
1646 | } \ | |
1da177e4 LT |
1647 | } while(0) |
1648 | ||
16a53ecc N |
1649 | static void compute_parity6(struct stripe_head *sh, int method) |
1650 | { | |
bff61975 | 1651 | raid5_conf_t *conf = sh->raid_conf; |
d0dabf7e | 1652 | int i, pd_idx, qd_idx, d0_idx, disks = sh->disks, count; |
67cc2b81 | 1653 | int syndrome_disks = sh->ddf_layout ? disks : (disks - 2); |
16a53ecc N |
1654 | struct bio *chosen; |
1655 | /**** FIX THIS: This could be very bad if disks is close to 256 ****/ | |
67cc2b81 | 1656 | void *ptrs[syndrome_disks+2]; |
16a53ecc | 1657 | |
d0dabf7e N |
1658 | pd_idx = sh->pd_idx; |
1659 | qd_idx = sh->qd_idx; | |
1660 | d0_idx = raid6_d0(sh); | |
16a53ecc | 1661 | |
45b4233c | 1662 | pr_debug("compute_parity, stripe %llu, method %d\n", |
16a53ecc N |
1663 | (unsigned long long)sh->sector, method); |
1664 | ||
1665 | switch(method) { | |
1666 | case READ_MODIFY_WRITE: | |
1667 | BUG(); /* READ_MODIFY_WRITE N/A for RAID-6 */ | |
1668 | case RECONSTRUCT_WRITE: | |
1669 | for (i= disks; i-- ;) | |
1670 | if ( i != pd_idx && i != qd_idx && sh->dev[i].towrite ) { | |
1671 | chosen = sh->dev[i].towrite; | |
1672 | sh->dev[i].towrite = NULL; | |
1673 | ||
1674 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) | |
1675 | wake_up(&conf->wait_for_overlap); | |
1676 | ||
52e5f9d1 | 1677 | BUG_ON(sh->dev[i].written); |
16a53ecc N |
1678 | sh->dev[i].written = chosen; |
1679 | } | |
1680 | break; | |
1681 | case CHECK_PARITY: | |
1682 | BUG(); /* Not implemented yet */ | |
1683 | } | |
1684 | ||
1685 | for (i = disks; i--;) | |
1686 | if (sh->dev[i].written) { | |
1687 | sector_t sector = sh->dev[i].sector; | |
1688 | struct bio *wbi = sh->dev[i].written; | |
1689 | while (wbi && wbi->bi_sector < sector + STRIPE_SECTORS) { | |
1690 | copy_data(1, wbi, sh->dev[i].page, sector); | |
1691 | wbi = r5_next_bio(wbi, sector); | |
1692 | } | |
1693 | ||
1694 | set_bit(R5_LOCKED, &sh->dev[i].flags); | |
1695 | set_bit(R5_UPTODATE, &sh->dev[i].flags); | |
1696 | } | |
1697 | ||
d0dabf7e | 1698 | /* Note that unlike RAID-5, the ordering of the disks matters greatly.*/ |
67cc2b81 N |
1699 | |
1700 | for (i = 0; i < disks; i++) | |
1701 | ptrs[i] = (void *)raid6_empty_zero_page; | |
1702 | ||
d0dabf7e N |
1703 | count = 0; |
1704 | i = d0_idx; | |
1705 | do { | |
67cc2b81 N |
1706 | int slot = raid6_idx_to_slot(i, sh, &count, syndrome_disks); |
1707 | ||
d0dabf7e | 1708 | ptrs[slot] = page_address(sh->dev[i].page); |
67cc2b81 | 1709 | if (slot < syndrome_disks && |
d0dabf7e N |
1710 | !test_bit(R5_UPTODATE, &sh->dev[i].flags)) { |
1711 | printk(KERN_ERR "block %d/%d not uptodate " | |
1712 | "on parity calc\n", i, count); | |
1713 | BUG(); | |
1714 | } | |
67cc2b81 | 1715 | |
d0dabf7e N |
1716 | i = raid6_next_disk(i, disks); |
1717 | } while (i != d0_idx); | |
67cc2b81 | 1718 | BUG_ON(count != syndrome_disks); |
16a53ecc | 1719 | |
67cc2b81 | 1720 | raid6_call.gen_syndrome(syndrome_disks+2, STRIPE_SIZE, ptrs); |
16a53ecc N |
1721 | |
1722 | switch(method) { | |
1723 | case RECONSTRUCT_WRITE: | |
1724 | set_bit(R5_UPTODATE, &sh->dev[pd_idx].flags); | |
1725 | set_bit(R5_UPTODATE, &sh->dev[qd_idx].flags); | |
1726 | set_bit(R5_LOCKED, &sh->dev[pd_idx].flags); | |
1727 | set_bit(R5_LOCKED, &sh->dev[qd_idx].flags); | |
1728 | break; | |
1729 | case UPDATE_PARITY: | |
1730 | set_bit(R5_UPTODATE, &sh->dev[pd_idx].flags); | |
1731 | set_bit(R5_UPTODATE, &sh->dev[qd_idx].flags); | |
1732 | break; | |
1733 | } | |
1734 | } | |
1735 | ||
1736 | ||
1737 | /* Compute one missing block */ | |
1738 | static void compute_block_1(struct stripe_head *sh, int dd_idx, int nozero) | |
1739 | { | |
f416885e | 1740 | int i, count, disks = sh->disks; |
9bc89cd8 | 1741 | void *ptr[MAX_XOR_BLOCKS], *dest, *p; |
d0dabf7e | 1742 | int qd_idx = sh->qd_idx; |
16a53ecc | 1743 | |
45b4233c | 1744 | pr_debug("compute_block_1, stripe %llu, idx %d\n", |
16a53ecc N |
1745 | (unsigned long long)sh->sector, dd_idx); |
1746 | ||
1747 | if ( dd_idx == qd_idx ) { | |
1748 | /* We're actually computing the Q drive */ | |
1749 | compute_parity6(sh, UPDATE_PARITY); | |
1750 | } else { | |
9bc89cd8 DW |
1751 | dest = page_address(sh->dev[dd_idx].page); |
1752 | if (!nozero) memset(dest, 0, STRIPE_SIZE); | |
1753 | count = 0; | |
16a53ecc N |
1754 | for (i = disks ; i--; ) { |
1755 | if (i == dd_idx || i == qd_idx) | |
1756 | continue; | |
1757 | p = page_address(sh->dev[i].page); | |
1758 | if (test_bit(R5_UPTODATE, &sh->dev[i].flags)) | |
1759 | ptr[count++] = p; | |
1760 | else | |
1761 | printk("compute_block() %d, stripe %llu, %d" | |
1762 | " not present\n", dd_idx, | |
1763 | (unsigned long long)sh->sector, i); | |
1764 | ||
1765 | check_xor(); | |
1766 | } | |
9bc89cd8 DW |
1767 | if (count) |
1768 | xor_blocks(count, STRIPE_SIZE, dest, ptr); | |
16a53ecc N |
1769 | if (!nozero) set_bit(R5_UPTODATE, &sh->dev[dd_idx].flags); |
1770 | else clear_bit(R5_UPTODATE, &sh->dev[dd_idx].flags); | |
1771 | } | |
1772 | } | |
1773 | ||
1774 | /* Compute two missing blocks */ | |
1775 | static void compute_block_2(struct stripe_head *sh, int dd_idx1, int dd_idx2) | |
1776 | { | |
f416885e | 1777 | int i, count, disks = sh->disks; |
67cc2b81 | 1778 | int syndrome_disks = sh->ddf_layout ? disks : disks-2; |
d0dabf7e N |
1779 | int d0_idx = raid6_d0(sh); |
1780 | int faila = -1, failb = -1; | |
1781 | /**** FIX THIS: This could be very bad if disks is close to 256 ****/ | |
67cc2b81 | 1782 | void *ptrs[syndrome_disks+2]; |
16a53ecc | 1783 | |
67cc2b81 N |
1784 | for (i = 0; i < disks ; i++) |
1785 | ptrs[i] = (void *)raid6_empty_zero_page; | |
d0dabf7e N |
1786 | count = 0; |
1787 | i = d0_idx; | |
1788 | do { | |
67cc2b81 N |
1789 | int slot = raid6_idx_to_slot(i, sh, &count, syndrome_disks); |
1790 | ||
d0dabf7e | 1791 | ptrs[slot] = page_address(sh->dev[i].page); |
67cc2b81 | 1792 | |
d0dabf7e N |
1793 | if (i == dd_idx1) |
1794 | faila = slot; | |
1795 | if (i == dd_idx2) | |
1796 | failb = slot; | |
1797 | i = raid6_next_disk(i, disks); | |
1798 | } while (i != d0_idx); | |
67cc2b81 | 1799 | BUG_ON(count != syndrome_disks); |
16a53ecc N |
1800 | |
1801 | BUG_ON(faila == failb); | |
1802 | if ( failb < faila ) { int tmp = faila; faila = failb; failb = tmp; } | |
1803 | ||
45b4233c | 1804 | pr_debug("compute_block_2, stripe %llu, idx %d,%d (%d,%d)\n", |
d0dabf7e N |
1805 | (unsigned long long)sh->sector, dd_idx1, dd_idx2, |
1806 | faila, failb); | |
16a53ecc | 1807 | |
67cc2b81 | 1808 | if (failb == syndrome_disks+1) { |
16a53ecc | 1809 | /* Q disk is one of the missing disks */ |
67cc2b81 | 1810 | if (faila == syndrome_disks) { |
16a53ecc N |
1811 | /* Missing P+Q, just recompute */ |
1812 | compute_parity6(sh, UPDATE_PARITY); | |
1813 | return; | |
1814 | } else { | |
1815 | /* We're missing D+Q; recompute D from P */ | |
d0dabf7e N |
1816 | compute_block_1(sh, ((dd_idx1 == sh->qd_idx) ? |
1817 | dd_idx2 : dd_idx1), | |
1818 | 0); | |
16a53ecc N |
1819 | compute_parity6(sh, UPDATE_PARITY); /* Is this necessary? */ |
1820 | return; | |
1821 | } | |
1822 | } | |
1823 | ||
d0dabf7e | 1824 | /* We're missing D+P or D+D; */ |
67cc2b81 | 1825 | if (failb == syndrome_disks) { |
d0dabf7e | 1826 | /* We're missing D+P. */ |
67cc2b81 | 1827 | raid6_datap_recov(syndrome_disks+2, STRIPE_SIZE, faila, ptrs); |
d0dabf7e N |
1828 | } else { |
1829 | /* We're missing D+D. */ | |
67cc2b81 N |
1830 | raid6_2data_recov(syndrome_disks+2, STRIPE_SIZE, faila, failb, |
1831 | ptrs); | |
16a53ecc | 1832 | } |
d0dabf7e N |
1833 | |
1834 | /* Both the above update both missing blocks */ | |
1835 | set_bit(R5_UPTODATE, &sh->dev[dd_idx1].flags); | |
1836 | set_bit(R5_UPTODATE, &sh->dev[dd_idx2].flags); | |
16a53ecc N |
1837 | } |
1838 | ||
600aa109 | 1839 | static void |
1fe797e6 | 1840 | schedule_reconstruction5(struct stripe_head *sh, struct stripe_head_state *s, |
600aa109 | 1841 | int rcw, int expand) |
e33129d8 DW |
1842 | { |
1843 | int i, pd_idx = sh->pd_idx, disks = sh->disks; | |
e33129d8 DW |
1844 | |
1845 | if (rcw) { | |
1846 | /* if we are not expanding this is a proper write request, and | |
1847 | * there will be bios with new data to be drained into the | |
1848 | * stripe cache | |
1849 | */ | |
1850 | if (!expand) { | |
600aa109 DW |
1851 | sh->reconstruct_state = reconstruct_state_drain_run; |
1852 | set_bit(STRIPE_OP_BIODRAIN, &s->ops_request); | |
1853 | } else | |
1854 | sh->reconstruct_state = reconstruct_state_run; | |
16a53ecc | 1855 | |
600aa109 | 1856 | set_bit(STRIPE_OP_POSTXOR, &s->ops_request); |
e33129d8 DW |
1857 | |
1858 | for (i = disks; i--; ) { | |
1859 | struct r5dev *dev = &sh->dev[i]; | |
1860 | ||
1861 | if (dev->towrite) { | |
1862 | set_bit(R5_LOCKED, &dev->flags); | |
d8ee0728 | 1863 | set_bit(R5_Wantdrain, &dev->flags); |
e33129d8 DW |
1864 | if (!expand) |
1865 | clear_bit(R5_UPTODATE, &dev->flags); | |
600aa109 | 1866 | s->locked++; |
e33129d8 DW |
1867 | } |
1868 | } | |
600aa109 | 1869 | if (s->locked + 1 == disks) |
8b3e6cdc DW |
1870 | if (!test_and_set_bit(STRIPE_FULL_WRITE, &sh->state)) |
1871 | atomic_inc(&sh->raid_conf->pending_full_writes); | |
e33129d8 DW |
1872 | } else { |
1873 | BUG_ON(!(test_bit(R5_UPTODATE, &sh->dev[pd_idx].flags) || | |
1874 | test_bit(R5_Wantcompute, &sh->dev[pd_idx].flags))); | |
1875 | ||
d8ee0728 | 1876 | sh->reconstruct_state = reconstruct_state_prexor_drain_run; |
600aa109 DW |
1877 | set_bit(STRIPE_OP_PREXOR, &s->ops_request); |
1878 | set_bit(STRIPE_OP_BIODRAIN, &s->ops_request); | |
1879 | set_bit(STRIPE_OP_POSTXOR, &s->ops_request); | |
e33129d8 DW |
1880 | |
1881 | for (i = disks; i--; ) { | |
1882 | struct r5dev *dev = &sh->dev[i]; | |
1883 | if (i == pd_idx) | |
1884 | continue; | |
1885 | ||
e33129d8 DW |
1886 | if (dev->towrite && |
1887 | (test_bit(R5_UPTODATE, &dev->flags) || | |
d8ee0728 DW |
1888 | test_bit(R5_Wantcompute, &dev->flags))) { |
1889 | set_bit(R5_Wantdrain, &dev->flags); | |
e33129d8 DW |
1890 | set_bit(R5_LOCKED, &dev->flags); |
1891 | clear_bit(R5_UPTODATE, &dev->flags); | |
600aa109 | 1892 | s->locked++; |
e33129d8 DW |
1893 | } |
1894 | } | |
1895 | } | |
1896 | ||
1897 | /* keep the parity disk locked while asynchronous operations | |
1898 | * are in flight | |
1899 | */ | |
1900 | set_bit(R5_LOCKED, &sh->dev[pd_idx].flags); | |
1901 | clear_bit(R5_UPTODATE, &sh->dev[pd_idx].flags); | |
600aa109 | 1902 | s->locked++; |
e33129d8 | 1903 | |
600aa109 | 1904 | pr_debug("%s: stripe %llu locked: %d ops_request: %lx\n", |
e46b272b | 1905 | __func__, (unsigned long long)sh->sector, |
600aa109 | 1906 | s->locked, s->ops_request); |
e33129d8 | 1907 | } |
16a53ecc | 1908 | |
1da177e4 LT |
1909 | /* |
1910 | * Each stripe/dev can have one or more bion attached. | |
16a53ecc | 1911 | * toread/towrite point to the first in a chain. |
1da177e4 LT |
1912 | * The bi_next chain must be in order. |
1913 | */ | |
1914 | static int add_stripe_bio(struct stripe_head *sh, struct bio *bi, int dd_idx, int forwrite) | |
1915 | { | |
1916 | struct bio **bip; | |
1917 | raid5_conf_t *conf = sh->raid_conf; | |
72626685 | 1918 | int firstwrite=0; |
1da177e4 | 1919 | |
45b4233c | 1920 | pr_debug("adding bh b#%llu to stripe s#%llu\n", |
1da177e4 LT |
1921 | (unsigned long long)bi->bi_sector, |
1922 | (unsigned long long)sh->sector); | |
1923 | ||
1924 | ||
1925 | spin_lock(&sh->lock); | |
1926 | spin_lock_irq(&conf->device_lock); | |
72626685 | 1927 | if (forwrite) { |
1da177e4 | 1928 | bip = &sh->dev[dd_idx].towrite; |
72626685 N |
1929 | if (*bip == NULL && sh->dev[dd_idx].written == NULL) |
1930 | firstwrite = 1; | |
1931 | } else | |
1da177e4 LT |
1932 | bip = &sh->dev[dd_idx].toread; |
1933 | while (*bip && (*bip)->bi_sector < bi->bi_sector) { | |
1934 | if ((*bip)->bi_sector + ((*bip)->bi_size >> 9) > bi->bi_sector) | |
1935 | goto overlap; | |
1936 | bip = & (*bip)->bi_next; | |
1937 | } | |
1938 | if (*bip && (*bip)->bi_sector < bi->bi_sector + ((bi->bi_size)>>9)) | |
1939 | goto overlap; | |
1940 | ||
78bafebd | 1941 | BUG_ON(*bip && bi->bi_next && (*bip) != bi->bi_next); |
1da177e4 LT |
1942 | if (*bip) |
1943 | bi->bi_next = *bip; | |
1944 | *bip = bi; | |
960e739d | 1945 | bi->bi_phys_segments++; |
1da177e4 LT |
1946 | spin_unlock_irq(&conf->device_lock); |
1947 | spin_unlock(&sh->lock); | |
1948 | ||
45b4233c | 1949 | pr_debug("added bi b#%llu to stripe s#%llu, disk %d.\n", |
1da177e4 LT |
1950 | (unsigned long long)bi->bi_sector, |
1951 | (unsigned long long)sh->sector, dd_idx); | |
1952 | ||
72626685 | 1953 | if (conf->mddev->bitmap && firstwrite) { |
72626685 N |
1954 | bitmap_startwrite(conf->mddev->bitmap, sh->sector, |
1955 | STRIPE_SECTORS, 0); | |
ae3c20cc | 1956 | sh->bm_seq = conf->seq_flush+1; |
72626685 N |
1957 | set_bit(STRIPE_BIT_DELAY, &sh->state); |
1958 | } | |
1959 | ||
1da177e4 LT |
1960 | if (forwrite) { |
1961 | /* check if page is covered */ | |
1962 | sector_t sector = sh->dev[dd_idx].sector; | |
1963 | for (bi=sh->dev[dd_idx].towrite; | |
1964 | sector < sh->dev[dd_idx].sector + STRIPE_SECTORS && | |
1965 | bi && bi->bi_sector <= sector; | |
1966 | bi = r5_next_bio(bi, sh->dev[dd_idx].sector)) { | |
1967 | if (bi->bi_sector + (bi->bi_size>>9) >= sector) | |
1968 | sector = bi->bi_sector + (bi->bi_size>>9); | |
1969 | } | |
1970 | if (sector >= sh->dev[dd_idx].sector + STRIPE_SECTORS) | |
1971 | set_bit(R5_OVERWRITE, &sh->dev[dd_idx].flags); | |
1972 | } | |
1973 | return 1; | |
1974 | ||
1975 | overlap: | |
1976 | set_bit(R5_Overlap, &sh->dev[dd_idx].flags); | |
1977 | spin_unlock_irq(&conf->device_lock); | |
1978 | spin_unlock(&sh->lock); | |
1979 | return 0; | |
1980 | } | |
1981 | ||
29269553 N |
1982 | static void end_reshape(raid5_conf_t *conf); |
1983 | ||
16a53ecc N |
1984 | static int page_is_zero(struct page *p) |
1985 | { | |
1986 | char *a = page_address(p); | |
1987 | return ((*(u32*)a) == 0 && | |
1988 | memcmp(a, a+4, STRIPE_SIZE-4)==0); | |
1989 | } | |
1990 | ||
911d4ee8 N |
1991 | static void stripe_set_idx(sector_t stripe, raid5_conf_t *conf, int previous, |
1992 | struct stripe_head *sh) | |
ccfcc3c1 N |
1993 | { |
1994 | int sectors_per_chunk = conf->chunk_size >> 9; | |
911d4ee8 | 1995 | int dd_idx; |
2d2063ce | 1996 | int chunk_offset = sector_div(stripe, sectors_per_chunk); |
112bf897 | 1997 | int disks = previous ? conf->previous_raid_disks : conf->raid_disks; |
2d2063ce | 1998 | |
112bf897 N |
1999 | raid5_compute_sector(conf, |
2000 | stripe * (disks - conf->max_degraded) | |
b875e531 | 2001 | *sectors_per_chunk + chunk_offset, |
112bf897 | 2002 | previous, |
911d4ee8 | 2003 | &dd_idx, sh); |
ccfcc3c1 N |
2004 | } |
2005 | ||
a4456856 | 2006 | static void |
1fe797e6 | 2007 | handle_failed_stripe(raid5_conf_t *conf, struct stripe_head *sh, |
a4456856 DW |
2008 | struct stripe_head_state *s, int disks, |
2009 | struct bio **return_bi) | |
2010 | { | |
2011 | int i; | |
2012 | for (i = disks; i--; ) { | |
2013 | struct bio *bi; | |
2014 | int bitmap_end = 0; | |
2015 | ||
2016 | if (test_bit(R5_ReadError, &sh->dev[i].flags)) { | |
2017 | mdk_rdev_t *rdev; | |
2018 | rcu_read_lock(); | |
2019 | rdev = rcu_dereference(conf->disks[i].rdev); | |
2020 | if (rdev && test_bit(In_sync, &rdev->flags)) | |
2021 | /* multiple read failures in one stripe */ | |
2022 | md_error(conf->mddev, rdev); | |
2023 | rcu_read_unlock(); | |
2024 | } | |
2025 | spin_lock_irq(&conf->device_lock); | |
2026 | /* fail all writes first */ | |
2027 | bi = sh->dev[i].towrite; | |
2028 | sh->dev[i].towrite = NULL; | |
2029 | if (bi) { | |
2030 | s->to_write--; | |
2031 | bitmap_end = 1; | |
2032 | } | |
2033 | ||
2034 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) | |
2035 | wake_up(&conf->wait_for_overlap); | |
2036 | ||
2037 | while (bi && bi->bi_sector < | |
2038 | sh->dev[i].sector + STRIPE_SECTORS) { | |
2039 | struct bio *nextbi = r5_next_bio(bi, sh->dev[i].sector); | |
2040 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
960e739d | 2041 | if (!raid5_dec_bi_phys_segments(bi)) { |
a4456856 DW |
2042 | md_write_end(conf->mddev); |
2043 | bi->bi_next = *return_bi; | |
2044 | *return_bi = bi; | |
2045 | } | |
2046 | bi = nextbi; | |
2047 | } | |
2048 | /* and fail all 'written' */ | |
2049 | bi = sh->dev[i].written; | |
2050 | sh->dev[i].written = NULL; | |
2051 | if (bi) bitmap_end = 1; | |
2052 | while (bi && bi->bi_sector < | |
2053 | sh->dev[i].sector + STRIPE_SECTORS) { | |
2054 | struct bio *bi2 = r5_next_bio(bi, sh->dev[i].sector); | |
2055 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
960e739d | 2056 | if (!raid5_dec_bi_phys_segments(bi)) { |
a4456856 DW |
2057 | md_write_end(conf->mddev); |
2058 | bi->bi_next = *return_bi; | |
2059 | *return_bi = bi; | |
2060 | } | |
2061 | bi = bi2; | |
2062 | } | |
2063 | ||
b5e98d65 DW |
2064 | /* fail any reads if this device is non-operational and |
2065 | * the data has not reached the cache yet. | |
2066 | */ | |
2067 | if (!test_bit(R5_Wantfill, &sh->dev[i].flags) && | |
2068 | (!test_bit(R5_Insync, &sh->dev[i].flags) || | |
2069 | test_bit(R5_ReadError, &sh->dev[i].flags))) { | |
a4456856 DW |
2070 | bi = sh->dev[i].toread; |
2071 | sh->dev[i].toread = NULL; | |
2072 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) | |
2073 | wake_up(&conf->wait_for_overlap); | |
2074 | if (bi) s->to_read--; | |
2075 | while (bi && bi->bi_sector < | |
2076 | sh->dev[i].sector + STRIPE_SECTORS) { | |
2077 | struct bio *nextbi = | |
2078 | r5_next_bio(bi, sh->dev[i].sector); | |
2079 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
960e739d | 2080 | if (!raid5_dec_bi_phys_segments(bi)) { |
a4456856 DW |
2081 | bi->bi_next = *return_bi; |
2082 | *return_bi = bi; | |
2083 | } | |
2084 | bi = nextbi; | |
2085 | } | |
2086 | } | |
2087 | spin_unlock_irq(&conf->device_lock); | |
2088 | if (bitmap_end) | |
2089 | bitmap_endwrite(conf->mddev->bitmap, sh->sector, | |
2090 | STRIPE_SECTORS, 0, 0); | |
2091 | } | |
2092 | ||
8b3e6cdc DW |
2093 | if (test_and_clear_bit(STRIPE_FULL_WRITE, &sh->state)) |
2094 | if (atomic_dec_and_test(&conf->pending_full_writes)) | |
2095 | md_wakeup_thread(conf->mddev->thread); | |
a4456856 DW |
2096 | } |
2097 | ||
1fe797e6 DW |
2098 | /* fetch_block5 - checks the given member device to see if its data needs |
2099 | * to be read or computed to satisfy a request. | |
2100 | * | |
2101 | * Returns 1 when no more member devices need to be checked, otherwise returns | |
2102 | * 0 to tell the loop in handle_stripe_fill5 to continue | |
f38e1219 | 2103 | */ |
1fe797e6 DW |
2104 | static int fetch_block5(struct stripe_head *sh, struct stripe_head_state *s, |
2105 | int disk_idx, int disks) | |
f38e1219 DW |
2106 | { |
2107 | struct r5dev *dev = &sh->dev[disk_idx]; | |
2108 | struct r5dev *failed_dev = &sh->dev[s->failed_num]; | |
2109 | ||
f38e1219 DW |
2110 | /* is the data in this block needed, and can we get it? */ |
2111 | if (!test_bit(R5_LOCKED, &dev->flags) && | |
1fe797e6 DW |
2112 | !test_bit(R5_UPTODATE, &dev->flags) && |
2113 | (dev->toread || | |
2114 | (dev->towrite && !test_bit(R5_OVERWRITE, &dev->flags)) || | |
2115 | s->syncing || s->expanding || | |
2116 | (s->failed && | |
2117 | (failed_dev->toread || | |
2118 | (failed_dev->towrite && | |
2119 | !test_bit(R5_OVERWRITE, &failed_dev->flags)))))) { | |
976ea8d4 DW |
2120 | /* We would like to get this block, possibly by computing it, |
2121 | * otherwise read it if the backing disk is insync | |
f38e1219 DW |
2122 | */ |
2123 | if ((s->uptodate == disks - 1) && | |
ecc65c9b | 2124 | (s->failed && disk_idx == s->failed_num)) { |
976ea8d4 DW |
2125 | set_bit(STRIPE_COMPUTE_RUN, &sh->state); |
2126 | set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request); | |
f38e1219 DW |
2127 | set_bit(R5_Wantcompute, &dev->flags); |
2128 | sh->ops.target = disk_idx; | |
2129 | s->req_compute = 1; | |
f38e1219 DW |
2130 | /* Careful: from this point on 'uptodate' is in the eye |
2131 | * of raid5_run_ops which services 'compute' operations | |
2132 | * before writes. R5_Wantcompute flags a block that will | |
2133 | * be R5_UPTODATE by the time it is needed for a | |
2134 | * subsequent operation. | |
2135 | */ | |
2136 | s->uptodate++; | |
1fe797e6 | 2137 | return 1; /* uptodate + compute == disks */ |
7a1fc53c | 2138 | } else if (test_bit(R5_Insync, &dev->flags)) { |
f38e1219 DW |
2139 | set_bit(R5_LOCKED, &dev->flags); |
2140 | set_bit(R5_Wantread, &dev->flags); | |
f38e1219 DW |
2141 | s->locked++; |
2142 | pr_debug("Reading block %d (sync=%d)\n", disk_idx, | |
2143 | s->syncing); | |
2144 | } | |
2145 | } | |
2146 | ||
1fe797e6 | 2147 | return 0; |
f38e1219 DW |
2148 | } |
2149 | ||
1fe797e6 DW |
2150 | /** |
2151 | * handle_stripe_fill5 - read or compute data to satisfy pending requests. | |
2152 | */ | |
2153 | static void handle_stripe_fill5(struct stripe_head *sh, | |
a4456856 DW |
2154 | struct stripe_head_state *s, int disks) |
2155 | { | |
2156 | int i; | |
f38e1219 | 2157 | |
f38e1219 DW |
2158 | /* look for blocks to read/compute, skip this if a compute |
2159 | * is already in flight, or if the stripe contents are in the | |
2160 | * midst of changing due to a write | |
2161 | */ | |
976ea8d4 | 2162 | if (!test_bit(STRIPE_COMPUTE_RUN, &sh->state) && !sh->check_state && |
1fe797e6 | 2163 | !sh->reconstruct_state) |
f38e1219 | 2164 | for (i = disks; i--; ) |
1fe797e6 | 2165 | if (fetch_block5(sh, s, i, disks)) |
f38e1219 | 2166 | break; |
a4456856 DW |
2167 | set_bit(STRIPE_HANDLE, &sh->state); |
2168 | } | |
2169 | ||
1fe797e6 | 2170 | static void handle_stripe_fill6(struct stripe_head *sh, |
a4456856 DW |
2171 | struct stripe_head_state *s, struct r6_state *r6s, |
2172 | int disks) | |
2173 | { | |
2174 | int i; | |
2175 | for (i = disks; i--; ) { | |
2176 | struct r5dev *dev = &sh->dev[i]; | |
2177 | if (!test_bit(R5_LOCKED, &dev->flags) && | |
2178 | !test_bit(R5_UPTODATE, &dev->flags) && | |
2179 | (dev->toread || (dev->towrite && | |
2180 | !test_bit(R5_OVERWRITE, &dev->flags)) || | |
2181 | s->syncing || s->expanding || | |
2182 | (s->failed >= 1 && | |
2183 | (sh->dev[r6s->failed_num[0]].toread || | |
2184 | s->to_write)) || | |
2185 | (s->failed >= 2 && | |
2186 | (sh->dev[r6s->failed_num[1]].toread || | |
2187 | s->to_write)))) { | |
2188 | /* we would like to get this block, possibly | |
2189 | * by computing it, but we might not be able to | |
2190 | */ | |
c337869d DW |
2191 | if ((s->uptodate == disks - 1) && |
2192 | (s->failed && (i == r6s->failed_num[0] || | |
2193 | i == r6s->failed_num[1]))) { | |
45b4233c | 2194 | pr_debug("Computing stripe %llu block %d\n", |
a4456856 DW |
2195 | (unsigned long long)sh->sector, i); |
2196 | compute_block_1(sh, i, 0); | |
2197 | s->uptodate++; | |
2198 | } else if ( s->uptodate == disks-2 && s->failed >= 2 ) { | |
2199 | /* Computing 2-failure is *very* expensive; only | |
2200 | * do it if failed >= 2 | |
2201 | */ | |
2202 | int other; | |
2203 | for (other = disks; other--; ) { | |
2204 | if (other == i) | |
2205 | continue; | |
2206 | if (!test_bit(R5_UPTODATE, | |
2207 | &sh->dev[other].flags)) | |
2208 | break; | |
2209 | } | |
2210 | BUG_ON(other < 0); | |
45b4233c | 2211 | pr_debug("Computing stripe %llu blocks %d,%d\n", |
a4456856 DW |
2212 | (unsigned long long)sh->sector, |
2213 | i, other); | |
2214 | compute_block_2(sh, i, other); | |
2215 | s->uptodate += 2; | |
2216 | } else if (test_bit(R5_Insync, &dev->flags)) { | |
2217 | set_bit(R5_LOCKED, &dev->flags); | |
2218 | set_bit(R5_Wantread, &dev->flags); | |
2219 | s->locked++; | |
45b4233c | 2220 | pr_debug("Reading block %d (sync=%d)\n", |
a4456856 DW |
2221 | i, s->syncing); |
2222 | } | |
2223 | } | |
2224 | } | |
2225 | set_bit(STRIPE_HANDLE, &sh->state); | |
2226 | } | |
2227 | ||
2228 | ||
1fe797e6 | 2229 | /* handle_stripe_clean_event |
a4456856 DW |
2230 | * any written block on an uptodate or failed drive can be returned. |
2231 | * Note that if we 'wrote' to a failed drive, it will be UPTODATE, but | |
2232 | * never LOCKED, so we don't need to test 'failed' directly. | |
2233 | */ | |
1fe797e6 | 2234 | static void handle_stripe_clean_event(raid5_conf_t *conf, |
a4456856 DW |
2235 | struct stripe_head *sh, int disks, struct bio **return_bi) |
2236 | { | |
2237 | int i; | |
2238 | struct r5dev *dev; | |
2239 | ||
2240 | for (i = disks; i--; ) | |
2241 | if (sh->dev[i].written) { | |
2242 | dev = &sh->dev[i]; | |
2243 | if (!test_bit(R5_LOCKED, &dev->flags) && | |
2244 | test_bit(R5_UPTODATE, &dev->flags)) { | |
2245 | /* We can return any write requests */ | |
2246 | struct bio *wbi, *wbi2; | |
2247 | int bitmap_end = 0; | |
45b4233c | 2248 | pr_debug("Return write for disc %d\n", i); |
a4456856 DW |
2249 | spin_lock_irq(&conf->device_lock); |
2250 | wbi = dev->written; | |
2251 | dev->written = NULL; | |
2252 | while (wbi && wbi->bi_sector < | |
2253 | dev->sector + STRIPE_SECTORS) { | |
2254 | wbi2 = r5_next_bio(wbi, dev->sector); | |
960e739d | 2255 | if (!raid5_dec_bi_phys_segments(wbi)) { |
a4456856 DW |
2256 | md_write_end(conf->mddev); |
2257 | wbi->bi_next = *return_bi; | |
2258 | *return_bi = wbi; | |
2259 | } | |
2260 | wbi = wbi2; | |
2261 | } | |
2262 | if (dev->towrite == NULL) | |
2263 | bitmap_end = 1; | |
2264 | spin_unlock_irq(&conf->device_lock); | |
2265 | if (bitmap_end) | |
2266 | bitmap_endwrite(conf->mddev->bitmap, | |
2267 | sh->sector, | |
2268 | STRIPE_SECTORS, | |
2269 | !test_bit(STRIPE_DEGRADED, &sh->state), | |
2270 | 0); | |
2271 | } | |
2272 | } | |
8b3e6cdc DW |
2273 | |
2274 | if (test_and_clear_bit(STRIPE_FULL_WRITE, &sh->state)) | |
2275 | if (atomic_dec_and_test(&conf->pending_full_writes)) | |
2276 | md_wakeup_thread(conf->mddev->thread); | |
a4456856 DW |
2277 | } |
2278 | ||
1fe797e6 | 2279 | static void handle_stripe_dirtying5(raid5_conf_t *conf, |
a4456856 DW |
2280 | struct stripe_head *sh, struct stripe_head_state *s, int disks) |
2281 | { | |
2282 | int rmw = 0, rcw = 0, i; | |
2283 | for (i = disks; i--; ) { | |
2284 | /* would I have to read this buffer for read_modify_write */ | |
2285 | struct r5dev *dev = &sh->dev[i]; | |
2286 | if ((dev->towrite || i == sh->pd_idx) && | |
2287 | !test_bit(R5_LOCKED, &dev->flags) && | |
f38e1219 DW |
2288 | !(test_bit(R5_UPTODATE, &dev->flags) || |
2289 | test_bit(R5_Wantcompute, &dev->flags))) { | |
a4456856 DW |
2290 | if (test_bit(R5_Insync, &dev->flags)) |
2291 | rmw++; | |
2292 | else | |
2293 | rmw += 2*disks; /* cannot read it */ | |
2294 | } | |
2295 | /* Would I have to read this buffer for reconstruct_write */ | |
2296 | if (!test_bit(R5_OVERWRITE, &dev->flags) && i != sh->pd_idx && | |
2297 | !test_bit(R5_LOCKED, &dev->flags) && | |
f38e1219 DW |
2298 | !(test_bit(R5_UPTODATE, &dev->flags) || |
2299 | test_bit(R5_Wantcompute, &dev->flags))) { | |
2300 | if (test_bit(R5_Insync, &dev->flags)) rcw++; | |
a4456856 DW |
2301 | else |
2302 | rcw += 2*disks; | |
2303 | } | |
2304 | } | |
45b4233c | 2305 | pr_debug("for sector %llu, rmw=%d rcw=%d\n", |
a4456856 DW |
2306 | (unsigned long long)sh->sector, rmw, rcw); |
2307 | set_bit(STRIPE_HANDLE, &sh->state); | |
2308 | if (rmw < rcw && rmw > 0) | |
2309 | /* prefer read-modify-write, but need to get some data */ | |
2310 | for (i = disks; i--; ) { | |
2311 | struct r5dev *dev = &sh->dev[i]; | |
2312 | if ((dev->towrite || i == sh->pd_idx) && | |
2313 | !test_bit(R5_LOCKED, &dev->flags) && | |
f38e1219 DW |
2314 | !(test_bit(R5_UPTODATE, &dev->flags) || |
2315 | test_bit(R5_Wantcompute, &dev->flags)) && | |
a4456856 DW |
2316 | test_bit(R5_Insync, &dev->flags)) { |
2317 | if ( | |
2318 | test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
45b4233c | 2319 | pr_debug("Read_old block " |
a4456856 DW |
2320 | "%d for r-m-w\n", i); |
2321 | set_bit(R5_LOCKED, &dev->flags); | |
2322 | set_bit(R5_Wantread, &dev->flags); | |
2323 | s->locked++; | |
2324 | } else { | |
2325 | set_bit(STRIPE_DELAYED, &sh->state); | |
2326 | set_bit(STRIPE_HANDLE, &sh->state); | |
2327 | } | |
2328 | } | |
2329 | } | |
2330 | if (rcw <= rmw && rcw > 0) | |
2331 | /* want reconstruct write, but need to get some data */ | |
2332 | for (i = disks; i--; ) { | |
2333 | struct r5dev *dev = &sh->dev[i]; | |
2334 | if (!test_bit(R5_OVERWRITE, &dev->flags) && | |
2335 | i != sh->pd_idx && | |
2336 | !test_bit(R5_LOCKED, &dev->flags) && | |
f38e1219 DW |
2337 | !(test_bit(R5_UPTODATE, &dev->flags) || |
2338 | test_bit(R5_Wantcompute, &dev->flags)) && | |
a4456856 DW |
2339 | test_bit(R5_Insync, &dev->flags)) { |
2340 | if ( | |
2341 | test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
45b4233c | 2342 | pr_debug("Read_old block " |
a4456856 DW |
2343 | "%d for Reconstruct\n", i); |
2344 | set_bit(R5_LOCKED, &dev->flags); | |
2345 | set_bit(R5_Wantread, &dev->flags); | |
2346 | s->locked++; | |
2347 | } else { | |
2348 | set_bit(STRIPE_DELAYED, &sh->state); | |
2349 | set_bit(STRIPE_HANDLE, &sh->state); | |
2350 | } | |
2351 | } | |
2352 | } | |
2353 | /* now if nothing is locked, and if we have enough data, | |
2354 | * we can start a write request | |
2355 | */ | |
f38e1219 DW |
2356 | /* since handle_stripe can be called at any time we need to handle the |
2357 | * case where a compute block operation has been submitted and then a | |
2358 | * subsequent call wants to start a write request. raid5_run_ops only | |
2359 | * handles the case where compute block and postxor are requested | |
2360 | * simultaneously. If this is not the case then new writes need to be | |
2361 | * held off until the compute completes. | |
2362 | */ | |
976ea8d4 DW |
2363 | if ((s->req_compute || !test_bit(STRIPE_COMPUTE_RUN, &sh->state)) && |
2364 | (s->locked == 0 && (rcw == 0 || rmw == 0) && | |
2365 | !test_bit(STRIPE_BIT_DELAY, &sh->state))) | |
1fe797e6 | 2366 | schedule_reconstruction5(sh, s, rcw == 0, 0); |
a4456856 DW |
2367 | } |
2368 | ||
1fe797e6 | 2369 | static void handle_stripe_dirtying6(raid5_conf_t *conf, |
a4456856 DW |
2370 | struct stripe_head *sh, struct stripe_head_state *s, |
2371 | struct r6_state *r6s, int disks) | |
2372 | { | |
2373 | int rcw = 0, must_compute = 0, pd_idx = sh->pd_idx, i; | |
34e04e87 | 2374 | int qd_idx = sh->qd_idx; |
a4456856 DW |
2375 | for (i = disks; i--; ) { |
2376 | struct r5dev *dev = &sh->dev[i]; | |
2377 | /* Would I have to read this buffer for reconstruct_write */ | |
2378 | if (!test_bit(R5_OVERWRITE, &dev->flags) | |
2379 | && i != pd_idx && i != qd_idx | |
2380 | && (!test_bit(R5_LOCKED, &dev->flags) | |
2381 | ) && | |
2382 | !test_bit(R5_UPTODATE, &dev->flags)) { | |
2383 | if (test_bit(R5_Insync, &dev->flags)) rcw++; | |
2384 | else { | |
45b4233c | 2385 | pr_debug("raid6: must_compute: " |
a4456856 DW |
2386 | "disk %d flags=%#lx\n", i, dev->flags); |
2387 | must_compute++; | |
2388 | } | |
2389 | } | |
2390 | } | |
45b4233c | 2391 | pr_debug("for sector %llu, rcw=%d, must_compute=%d\n", |
a4456856 DW |
2392 | (unsigned long long)sh->sector, rcw, must_compute); |
2393 | set_bit(STRIPE_HANDLE, &sh->state); | |
2394 | ||
2395 | if (rcw > 0) | |
2396 | /* want reconstruct write, but need to get some data */ | |
2397 | for (i = disks; i--; ) { | |
2398 | struct r5dev *dev = &sh->dev[i]; | |
2399 | if (!test_bit(R5_OVERWRITE, &dev->flags) | |
2400 | && !(s->failed == 0 && (i == pd_idx || i == qd_idx)) | |
2401 | && !test_bit(R5_LOCKED, &dev->flags) && | |
2402 | !test_bit(R5_UPTODATE, &dev->flags) && | |
2403 | test_bit(R5_Insync, &dev->flags)) { | |
2404 | if ( | |
2405 | test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
45b4233c | 2406 | pr_debug("Read_old stripe %llu " |
a4456856 DW |
2407 | "block %d for Reconstruct\n", |
2408 | (unsigned long long)sh->sector, i); | |
2409 | set_bit(R5_LOCKED, &dev->flags); | |
2410 | set_bit(R5_Wantread, &dev->flags); | |
2411 | s->locked++; | |
2412 | } else { | |
45b4233c | 2413 | pr_debug("Request delayed stripe %llu " |
a4456856 DW |
2414 | "block %d for Reconstruct\n", |
2415 | (unsigned long long)sh->sector, i); | |
2416 | set_bit(STRIPE_DELAYED, &sh->state); | |
2417 | set_bit(STRIPE_HANDLE, &sh->state); | |
2418 | } | |
2419 | } | |
2420 | } | |
2421 | /* now if nothing is locked, and if we have enough data, we can start a | |
2422 | * write request | |
2423 | */ | |
2424 | if (s->locked == 0 && rcw == 0 && | |
2425 | !test_bit(STRIPE_BIT_DELAY, &sh->state)) { | |
2426 | if (must_compute > 0) { | |
2427 | /* We have failed blocks and need to compute them */ | |
2428 | switch (s->failed) { | |
2429 | case 0: | |
2430 | BUG(); | |
2431 | case 1: | |
2432 | compute_block_1(sh, r6s->failed_num[0], 0); | |
2433 | break; | |
2434 | case 2: | |
2435 | compute_block_2(sh, r6s->failed_num[0], | |
2436 | r6s->failed_num[1]); | |
2437 | break; | |
2438 | default: /* This request should have been failed? */ | |
2439 | BUG(); | |
2440 | } | |
2441 | } | |
2442 | ||
45b4233c | 2443 | pr_debug("Computing parity for stripe %llu\n", |
a4456856 DW |
2444 | (unsigned long long)sh->sector); |
2445 | compute_parity6(sh, RECONSTRUCT_WRITE); | |
2446 | /* now every locked buffer is ready to be written */ | |
2447 | for (i = disks; i--; ) | |
2448 | if (test_bit(R5_LOCKED, &sh->dev[i].flags)) { | |
45b4233c | 2449 | pr_debug("Writing stripe %llu block %d\n", |
a4456856 DW |
2450 | (unsigned long long)sh->sector, i); |
2451 | s->locked++; | |
2452 | set_bit(R5_Wantwrite, &sh->dev[i].flags); | |
2453 | } | |
8b3e6cdc DW |
2454 | if (s->locked == disks) |
2455 | if (!test_and_set_bit(STRIPE_FULL_WRITE, &sh->state)) | |
2456 | atomic_inc(&conf->pending_full_writes); | |
a4456856 DW |
2457 | /* after a RECONSTRUCT_WRITE, the stripe MUST be in-sync */ |
2458 | set_bit(STRIPE_INSYNC, &sh->state); | |
2459 | ||
2460 | if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
2461 | atomic_dec(&conf->preread_active_stripes); | |
2462 | if (atomic_read(&conf->preread_active_stripes) < | |
2463 | IO_THRESHOLD) | |
2464 | md_wakeup_thread(conf->mddev->thread); | |
2465 | } | |
2466 | } | |
2467 | } | |
2468 | ||
2469 | static void handle_parity_checks5(raid5_conf_t *conf, struct stripe_head *sh, | |
2470 | struct stripe_head_state *s, int disks) | |
2471 | { | |
ecc65c9b | 2472 | struct r5dev *dev = NULL; |
bd2ab670 | 2473 | |
a4456856 | 2474 | set_bit(STRIPE_HANDLE, &sh->state); |
e89f8962 | 2475 | |
ecc65c9b DW |
2476 | switch (sh->check_state) { |
2477 | case check_state_idle: | |
2478 | /* start a new check operation if there are no failures */ | |
bd2ab670 | 2479 | if (s->failed == 0) { |
bd2ab670 | 2480 | BUG_ON(s->uptodate != disks); |
ecc65c9b DW |
2481 | sh->check_state = check_state_run; |
2482 | set_bit(STRIPE_OP_CHECK, &s->ops_request); | |
bd2ab670 | 2483 | clear_bit(R5_UPTODATE, &sh->dev[sh->pd_idx].flags); |
bd2ab670 | 2484 | s->uptodate--; |
ecc65c9b | 2485 | break; |
bd2ab670 | 2486 | } |
ecc65c9b DW |
2487 | dev = &sh->dev[s->failed_num]; |
2488 | /* fall through */ | |
2489 | case check_state_compute_result: | |
2490 | sh->check_state = check_state_idle; | |
2491 | if (!dev) | |
2492 | dev = &sh->dev[sh->pd_idx]; | |
2493 | ||
2494 | /* check that a write has not made the stripe insync */ | |
2495 | if (test_bit(STRIPE_INSYNC, &sh->state)) | |
2496 | break; | |
c8894419 | 2497 | |
a4456856 | 2498 | /* either failed parity check, or recovery is happening */ |
a4456856 DW |
2499 | BUG_ON(!test_bit(R5_UPTODATE, &dev->flags)); |
2500 | BUG_ON(s->uptodate != disks); | |
2501 | ||
2502 | set_bit(R5_LOCKED, &dev->flags); | |
ecc65c9b | 2503 | s->locked++; |
a4456856 | 2504 | set_bit(R5_Wantwrite, &dev->flags); |
830ea016 | 2505 | |
a4456856 | 2506 | clear_bit(STRIPE_DEGRADED, &sh->state); |
a4456856 | 2507 | set_bit(STRIPE_INSYNC, &sh->state); |
ecc65c9b DW |
2508 | break; |
2509 | case check_state_run: | |
2510 | break; /* we will be called again upon completion */ | |
2511 | case check_state_check_result: | |
2512 | sh->check_state = check_state_idle; | |
2513 | ||
2514 | /* if a failure occurred during the check operation, leave | |
2515 | * STRIPE_INSYNC not set and let the stripe be handled again | |
2516 | */ | |
2517 | if (s->failed) | |
2518 | break; | |
2519 | ||
2520 | /* handle a successful check operation, if parity is correct | |
2521 | * we are done. Otherwise update the mismatch count and repair | |
2522 | * parity if !MD_RECOVERY_CHECK | |
2523 | */ | |
2524 | if (sh->ops.zero_sum_result == 0) | |
2525 | /* parity is correct (on disc, | |
2526 | * not in buffer any more) | |
2527 | */ | |
2528 | set_bit(STRIPE_INSYNC, &sh->state); | |
2529 | else { | |
2530 | conf->mddev->resync_mismatches += STRIPE_SECTORS; | |
2531 | if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery)) | |
2532 | /* don't try to repair!! */ | |
2533 | set_bit(STRIPE_INSYNC, &sh->state); | |
2534 | else { | |
2535 | sh->check_state = check_state_compute_run; | |
976ea8d4 | 2536 | set_bit(STRIPE_COMPUTE_RUN, &sh->state); |
ecc65c9b DW |
2537 | set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request); |
2538 | set_bit(R5_Wantcompute, | |
2539 | &sh->dev[sh->pd_idx].flags); | |
2540 | sh->ops.target = sh->pd_idx; | |
2541 | s->uptodate++; | |
2542 | } | |
2543 | } | |
2544 | break; | |
2545 | case check_state_compute_run: | |
2546 | break; | |
2547 | default: | |
2548 | printk(KERN_ERR "%s: unknown check_state: %d sector: %llu\n", | |
2549 | __func__, sh->check_state, | |
2550 | (unsigned long long) sh->sector); | |
2551 | BUG(); | |
a4456856 DW |
2552 | } |
2553 | } | |
2554 | ||
2555 | ||
2556 | static void handle_parity_checks6(raid5_conf_t *conf, struct stripe_head *sh, | |
2557 | struct stripe_head_state *s, | |
2558 | struct r6_state *r6s, struct page *tmp_page, | |
2559 | int disks) | |
2560 | { | |
2561 | int update_p = 0, update_q = 0; | |
2562 | struct r5dev *dev; | |
2563 | int pd_idx = sh->pd_idx; | |
34e04e87 | 2564 | int qd_idx = sh->qd_idx; |
a4456856 DW |
2565 | |
2566 | set_bit(STRIPE_HANDLE, &sh->state); | |
2567 | ||
2568 | BUG_ON(s->failed > 2); | |
2569 | BUG_ON(s->uptodate < disks); | |
2570 | /* Want to check and possibly repair P and Q. | |
2571 | * However there could be one 'failed' device, in which | |
2572 | * case we can only check one of them, possibly using the | |
2573 | * other to generate missing data | |
2574 | */ | |
2575 | ||
2576 | /* If !tmp_page, we cannot do the calculations, | |
2577 | * but as we have set STRIPE_HANDLE, we will soon be called | |
2578 | * by stripe_handle with a tmp_page - just wait until then. | |
2579 | */ | |
2580 | if (tmp_page) { | |
2581 | if (s->failed == r6s->q_failed) { | |
2582 | /* The only possible failed device holds 'Q', so it | |
2583 | * makes sense to check P (If anything else were failed, | |
2584 | * we would have used P to recreate it). | |
2585 | */ | |
2586 | compute_block_1(sh, pd_idx, 1); | |
2587 | if (!page_is_zero(sh->dev[pd_idx].page)) { | |
2588 | compute_block_1(sh, pd_idx, 0); | |
2589 | update_p = 1; | |
2590 | } | |
2591 | } | |
2592 | if (!r6s->q_failed && s->failed < 2) { | |
2593 | /* q is not failed, and we didn't use it to generate | |
2594 | * anything, so it makes sense to check it | |
2595 | */ | |
2596 | memcpy(page_address(tmp_page), | |
2597 | page_address(sh->dev[qd_idx].page), | |
2598 | STRIPE_SIZE); | |
2599 | compute_parity6(sh, UPDATE_PARITY); | |
2600 | if (memcmp(page_address(tmp_page), | |
2601 | page_address(sh->dev[qd_idx].page), | |
2602 | STRIPE_SIZE) != 0) { | |
2603 | clear_bit(STRIPE_INSYNC, &sh->state); | |
2604 | update_q = 1; | |
2605 | } | |
2606 | } | |
2607 | if (update_p || update_q) { | |
2608 | conf->mddev->resync_mismatches += STRIPE_SECTORS; | |
2609 | if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery)) | |
2610 | /* don't try to repair!! */ | |
2611 | update_p = update_q = 0; | |
2612 | } | |
2613 | ||
2614 | /* now write out any block on a failed drive, | |
2615 | * or P or Q if they need it | |
2616 | */ | |
2617 | ||
2618 | if (s->failed == 2) { | |
2619 | dev = &sh->dev[r6s->failed_num[1]]; | |
2620 | s->locked++; | |
2621 | set_bit(R5_LOCKED, &dev->flags); | |
2622 | set_bit(R5_Wantwrite, &dev->flags); | |
2623 | } | |
2624 | if (s->failed >= 1) { | |
2625 | dev = &sh->dev[r6s->failed_num[0]]; | |
2626 | s->locked++; | |
2627 | set_bit(R5_LOCKED, &dev->flags); | |
2628 | set_bit(R5_Wantwrite, &dev->flags); | |
2629 | } | |
2630 | ||
2631 | if (update_p) { | |
2632 | dev = &sh->dev[pd_idx]; | |
2633 | s->locked++; | |
2634 | set_bit(R5_LOCKED, &dev->flags); | |
2635 | set_bit(R5_Wantwrite, &dev->flags); | |
2636 | } | |
2637 | if (update_q) { | |
2638 | dev = &sh->dev[qd_idx]; | |
2639 | s->locked++; | |
2640 | set_bit(R5_LOCKED, &dev->flags); | |
2641 | set_bit(R5_Wantwrite, &dev->flags); | |
2642 | } | |
2643 | clear_bit(STRIPE_DEGRADED, &sh->state); | |
2644 | ||
2645 | set_bit(STRIPE_INSYNC, &sh->state); | |
2646 | } | |
2647 | } | |
2648 | ||
2649 | static void handle_stripe_expansion(raid5_conf_t *conf, struct stripe_head *sh, | |
2650 | struct r6_state *r6s) | |
2651 | { | |
2652 | int i; | |
2653 | ||
2654 | /* We have read all the blocks in this stripe and now we need to | |
2655 | * copy some of them into a target stripe for expand. | |
2656 | */ | |
f0a50d37 | 2657 | struct dma_async_tx_descriptor *tx = NULL; |
a4456856 DW |
2658 | clear_bit(STRIPE_EXPAND_SOURCE, &sh->state); |
2659 | for (i = 0; i < sh->disks; i++) | |
34e04e87 | 2660 | if (i != sh->pd_idx && i != sh->qd_idx) { |
911d4ee8 | 2661 | int dd_idx, j; |
a4456856 DW |
2662 | struct stripe_head *sh2; |
2663 | ||
2664 | sector_t bn = compute_blocknr(sh, i); | |
911d4ee8 N |
2665 | sector_t s = raid5_compute_sector(conf, bn, 0, |
2666 | &dd_idx, NULL); | |
b5663ba4 | 2667 | sh2 = get_active_stripe(conf, s, 0, 1); |
a4456856 DW |
2668 | if (sh2 == NULL) |
2669 | /* so far only the early blocks of this stripe | |
2670 | * have been requested. When later blocks | |
2671 | * get requested, we will try again | |
2672 | */ | |
2673 | continue; | |
2674 | if (!test_bit(STRIPE_EXPANDING, &sh2->state) || | |
2675 | test_bit(R5_Expanded, &sh2->dev[dd_idx].flags)) { | |
2676 | /* must have already done this block */ | |
2677 | release_stripe(sh2); | |
2678 | continue; | |
2679 | } | |
f0a50d37 DW |
2680 | |
2681 | /* place all the copies on one channel */ | |
2682 | tx = async_memcpy(sh2->dev[dd_idx].page, | |
2683 | sh->dev[i].page, 0, 0, STRIPE_SIZE, | |
2684 | ASYNC_TX_DEP_ACK, tx, NULL, NULL); | |
2685 | ||
a4456856 DW |
2686 | set_bit(R5_Expanded, &sh2->dev[dd_idx].flags); |
2687 | set_bit(R5_UPTODATE, &sh2->dev[dd_idx].flags); | |
2688 | for (j = 0; j < conf->raid_disks; j++) | |
2689 | if (j != sh2->pd_idx && | |
d0dabf7e | 2690 | (!r6s || j != sh2->qd_idx) && |
a4456856 DW |
2691 | !test_bit(R5_Expanded, &sh2->dev[j].flags)) |
2692 | break; | |
2693 | if (j == conf->raid_disks) { | |
2694 | set_bit(STRIPE_EXPAND_READY, &sh2->state); | |
2695 | set_bit(STRIPE_HANDLE, &sh2->state); | |
2696 | } | |
2697 | release_stripe(sh2); | |
f0a50d37 | 2698 | |
a4456856 | 2699 | } |
a2e08551 N |
2700 | /* done submitting copies, wait for them to complete */ |
2701 | if (tx) { | |
2702 | async_tx_ack(tx); | |
2703 | dma_wait_for_async_tx(tx); | |
2704 | } | |
a4456856 | 2705 | } |
1da177e4 | 2706 | |
6bfe0b49 | 2707 | |
1da177e4 LT |
2708 | /* |
2709 | * handle_stripe - do things to a stripe. | |
2710 | * | |
2711 | * We lock the stripe and then examine the state of various bits | |
2712 | * to see what needs to be done. | |
2713 | * Possible results: | |
2714 | * return some read request which now have data | |
2715 | * return some write requests which are safely on disc | |
2716 | * schedule a read on some buffers | |
2717 | * schedule a write of some buffers | |
2718 | * return confirmation of parity correctness | |
2719 | * | |
1da177e4 LT |
2720 | * buffers are taken off read_list or write_list, and bh_cache buffers |
2721 | * get BH_Lock set before the stripe lock is released. | |
2722 | * | |
2723 | */ | |
a4456856 | 2724 | |
df10cfbc | 2725 | static bool handle_stripe5(struct stripe_head *sh) |
1da177e4 LT |
2726 | { |
2727 | raid5_conf_t *conf = sh->raid_conf; | |
a4456856 DW |
2728 | int disks = sh->disks, i; |
2729 | struct bio *return_bi = NULL; | |
2730 | struct stripe_head_state s; | |
1da177e4 | 2731 | struct r5dev *dev; |
6bfe0b49 | 2732 | mdk_rdev_t *blocked_rdev = NULL; |
e0a115e5 | 2733 | int prexor; |
1da177e4 | 2734 | |
a4456856 | 2735 | memset(&s, 0, sizeof(s)); |
600aa109 DW |
2736 | pr_debug("handling stripe %llu, state=%#lx cnt=%d, pd_idx=%d check:%d " |
2737 | "reconstruct:%d\n", (unsigned long long)sh->sector, sh->state, | |
2738 | atomic_read(&sh->count), sh->pd_idx, sh->check_state, | |
2739 | sh->reconstruct_state); | |
1da177e4 LT |
2740 | |
2741 | spin_lock(&sh->lock); | |
2742 | clear_bit(STRIPE_HANDLE, &sh->state); | |
2743 | clear_bit(STRIPE_DELAYED, &sh->state); | |
2744 | ||
a4456856 DW |
2745 | s.syncing = test_bit(STRIPE_SYNCING, &sh->state); |
2746 | s.expanding = test_bit(STRIPE_EXPAND_SOURCE, &sh->state); | |
2747 | s.expanded = test_bit(STRIPE_EXPAND_READY, &sh->state); | |
def6ae26 | 2748 | |
83de75cc | 2749 | /* Now to look around and see what can be done */ |
9910f16a | 2750 | rcu_read_lock(); |
1da177e4 LT |
2751 | for (i=disks; i--; ) { |
2752 | mdk_rdev_t *rdev; | |
a4456856 | 2753 | struct r5dev *dev = &sh->dev[i]; |
1da177e4 | 2754 | clear_bit(R5_Insync, &dev->flags); |
1da177e4 | 2755 | |
b5e98d65 DW |
2756 | pr_debug("check %d: state 0x%lx toread %p read %p write %p " |
2757 | "written %p\n", i, dev->flags, dev->toread, dev->read, | |
2758 | dev->towrite, dev->written); | |
2759 | ||
2760 | /* maybe we can request a biofill operation | |
2761 | * | |
2762 | * new wantfill requests are only permitted while | |
83de75cc | 2763 | * ops_complete_biofill is guaranteed to be inactive |
b5e98d65 DW |
2764 | */ |
2765 | if (test_bit(R5_UPTODATE, &dev->flags) && dev->toread && | |
83de75cc | 2766 | !test_bit(STRIPE_BIOFILL_RUN, &sh->state)) |
b5e98d65 | 2767 | set_bit(R5_Wantfill, &dev->flags); |
1da177e4 LT |
2768 | |
2769 | /* now count some things */ | |
a4456856 DW |
2770 | if (test_bit(R5_LOCKED, &dev->flags)) s.locked++; |
2771 | if (test_bit(R5_UPTODATE, &dev->flags)) s.uptodate++; | |
f38e1219 | 2772 | if (test_bit(R5_Wantcompute, &dev->flags)) s.compute++; |
1da177e4 | 2773 | |
b5e98d65 DW |
2774 | if (test_bit(R5_Wantfill, &dev->flags)) |
2775 | s.to_fill++; | |
2776 | else if (dev->toread) | |
a4456856 | 2777 | s.to_read++; |
1da177e4 | 2778 | if (dev->towrite) { |
a4456856 | 2779 | s.to_write++; |
1da177e4 | 2780 | if (!test_bit(R5_OVERWRITE, &dev->flags)) |
a4456856 | 2781 | s.non_overwrite++; |
1da177e4 | 2782 | } |
a4456856 DW |
2783 | if (dev->written) |
2784 | s.written++; | |
9910f16a | 2785 | rdev = rcu_dereference(conf->disks[i].rdev); |
ac4090d2 N |
2786 | if (blocked_rdev == NULL && |
2787 | rdev && unlikely(test_bit(Blocked, &rdev->flags))) { | |
6bfe0b49 DW |
2788 | blocked_rdev = rdev; |
2789 | atomic_inc(&rdev->nr_pending); | |
6bfe0b49 | 2790 | } |
b2d444d7 | 2791 | if (!rdev || !test_bit(In_sync, &rdev->flags)) { |
14f8d26b | 2792 | /* The ReadError flag will just be confusing now */ |
4e5314b5 N |
2793 | clear_bit(R5_ReadError, &dev->flags); |
2794 | clear_bit(R5_ReWrite, &dev->flags); | |
2795 | } | |
b2d444d7 | 2796 | if (!rdev || !test_bit(In_sync, &rdev->flags) |
4e5314b5 | 2797 | || test_bit(R5_ReadError, &dev->flags)) { |
a4456856 DW |
2798 | s.failed++; |
2799 | s.failed_num = i; | |
1da177e4 LT |
2800 | } else |
2801 | set_bit(R5_Insync, &dev->flags); | |
2802 | } | |
9910f16a | 2803 | rcu_read_unlock(); |
b5e98d65 | 2804 | |
6bfe0b49 | 2805 | if (unlikely(blocked_rdev)) { |
ac4090d2 N |
2806 | if (s.syncing || s.expanding || s.expanded || |
2807 | s.to_write || s.written) { | |
2808 | set_bit(STRIPE_HANDLE, &sh->state); | |
2809 | goto unlock; | |
2810 | } | |
2811 | /* There is nothing for the blocked_rdev to block */ | |
2812 | rdev_dec_pending(blocked_rdev, conf->mddev); | |
2813 | blocked_rdev = NULL; | |
6bfe0b49 DW |
2814 | } |
2815 | ||
83de75cc DW |
2816 | if (s.to_fill && !test_bit(STRIPE_BIOFILL_RUN, &sh->state)) { |
2817 | set_bit(STRIPE_OP_BIOFILL, &s.ops_request); | |
2818 | set_bit(STRIPE_BIOFILL_RUN, &sh->state); | |
2819 | } | |
b5e98d65 | 2820 | |
45b4233c | 2821 | pr_debug("locked=%d uptodate=%d to_read=%d" |
1da177e4 | 2822 | " to_write=%d failed=%d failed_num=%d\n", |
a4456856 DW |
2823 | s.locked, s.uptodate, s.to_read, s.to_write, |
2824 | s.failed, s.failed_num); | |
1da177e4 LT |
2825 | /* check if the array has lost two devices and, if so, some requests might |
2826 | * need to be failed | |
2827 | */ | |
a4456856 | 2828 | if (s.failed > 1 && s.to_read+s.to_write+s.written) |
1fe797e6 | 2829 | handle_failed_stripe(conf, sh, &s, disks, &return_bi); |
a4456856 | 2830 | if (s.failed > 1 && s.syncing) { |
1da177e4 LT |
2831 | md_done_sync(conf->mddev, STRIPE_SECTORS,0); |
2832 | clear_bit(STRIPE_SYNCING, &sh->state); | |
a4456856 | 2833 | s.syncing = 0; |
1da177e4 LT |
2834 | } |
2835 | ||
2836 | /* might be able to return some write requests if the parity block | |
2837 | * is safe, or on a failed drive | |
2838 | */ | |
2839 | dev = &sh->dev[sh->pd_idx]; | |
a4456856 DW |
2840 | if ( s.written && |
2841 | ((test_bit(R5_Insync, &dev->flags) && | |
2842 | !test_bit(R5_LOCKED, &dev->flags) && | |
2843 | test_bit(R5_UPTODATE, &dev->flags)) || | |
2844 | (s.failed == 1 && s.failed_num == sh->pd_idx))) | |
1fe797e6 | 2845 | handle_stripe_clean_event(conf, sh, disks, &return_bi); |
1da177e4 LT |
2846 | |
2847 | /* Now we might consider reading some blocks, either to check/generate | |
2848 | * parity, or to satisfy requests | |
2849 | * or to load a block that is being partially written. | |
2850 | */ | |
a4456856 | 2851 | if (s.to_read || s.non_overwrite || |
976ea8d4 | 2852 | (s.syncing && (s.uptodate + s.compute < disks)) || s.expanding) |
1fe797e6 | 2853 | handle_stripe_fill5(sh, &s, disks); |
1da177e4 | 2854 | |
e33129d8 DW |
2855 | /* Now we check to see if any write operations have recently |
2856 | * completed | |
2857 | */ | |
e0a115e5 | 2858 | prexor = 0; |
d8ee0728 | 2859 | if (sh->reconstruct_state == reconstruct_state_prexor_drain_result) |
e0a115e5 | 2860 | prexor = 1; |
d8ee0728 DW |
2861 | if (sh->reconstruct_state == reconstruct_state_drain_result || |
2862 | sh->reconstruct_state == reconstruct_state_prexor_drain_result) { | |
600aa109 | 2863 | sh->reconstruct_state = reconstruct_state_idle; |
e33129d8 DW |
2864 | |
2865 | /* All the 'written' buffers and the parity block are ready to | |
2866 | * be written back to disk | |
2867 | */ | |
2868 | BUG_ON(!test_bit(R5_UPTODATE, &sh->dev[sh->pd_idx].flags)); | |
2869 | for (i = disks; i--; ) { | |
2870 | dev = &sh->dev[i]; | |
2871 | if (test_bit(R5_LOCKED, &dev->flags) && | |
2872 | (i == sh->pd_idx || dev->written)) { | |
2873 | pr_debug("Writing block %d\n", i); | |
2874 | set_bit(R5_Wantwrite, &dev->flags); | |
e0a115e5 DW |
2875 | if (prexor) |
2876 | continue; | |
e33129d8 DW |
2877 | if (!test_bit(R5_Insync, &dev->flags) || |
2878 | (i == sh->pd_idx && s.failed == 0)) | |
2879 | set_bit(STRIPE_INSYNC, &sh->state); | |
2880 | } | |
2881 | } | |
2882 | if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
2883 | atomic_dec(&conf->preread_active_stripes); | |
2884 | if (atomic_read(&conf->preread_active_stripes) < | |
2885 | IO_THRESHOLD) | |
2886 | md_wakeup_thread(conf->mddev->thread); | |
2887 | } | |
2888 | } | |
2889 | ||
2890 | /* Now to consider new write requests and what else, if anything | |
2891 | * should be read. We do not handle new writes when: | |
2892 | * 1/ A 'write' operation (copy+xor) is already in flight. | |
2893 | * 2/ A 'check' operation is in flight, as it may clobber the parity | |
2894 | * block. | |
2895 | */ | |
600aa109 | 2896 | if (s.to_write && !sh->reconstruct_state && !sh->check_state) |
1fe797e6 | 2897 | handle_stripe_dirtying5(conf, sh, &s, disks); |
1da177e4 LT |
2898 | |
2899 | /* maybe we need to check and possibly fix the parity for this stripe | |
e89f8962 DW |
2900 | * Any reads will already have been scheduled, so we just see if enough |
2901 | * data is available. The parity check is held off while parity | |
2902 | * dependent operations are in flight. | |
1da177e4 | 2903 | */ |
ecc65c9b DW |
2904 | if (sh->check_state || |
2905 | (s.syncing && s.locked == 0 && | |
976ea8d4 | 2906 | !test_bit(STRIPE_COMPUTE_RUN, &sh->state) && |
ecc65c9b | 2907 | !test_bit(STRIPE_INSYNC, &sh->state))) |
a4456856 | 2908 | handle_parity_checks5(conf, sh, &s, disks); |
e89f8962 | 2909 | |
a4456856 | 2910 | if (s.syncing && s.locked == 0 && test_bit(STRIPE_INSYNC, &sh->state)) { |
1da177e4 LT |
2911 | md_done_sync(conf->mddev, STRIPE_SECTORS,1); |
2912 | clear_bit(STRIPE_SYNCING, &sh->state); | |
2913 | } | |
4e5314b5 N |
2914 | |
2915 | /* If the failed drive is just a ReadError, then we might need to progress | |
2916 | * the repair/check process | |
2917 | */ | |
a4456856 DW |
2918 | if (s.failed == 1 && !conf->mddev->ro && |
2919 | test_bit(R5_ReadError, &sh->dev[s.failed_num].flags) | |
2920 | && !test_bit(R5_LOCKED, &sh->dev[s.failed_num].flags) | |
2921 | && test_bit(R5_UPTODATE, &sh->dev[s.failed_num].flags) | |
4e5314b5 | 2922 | ) { |
a4456856 | 2923 | dev = &sh->dev[s.failed_num]; |
4e5314b5 N |
2924 | if (!test_bit(R5_ReWrite, &dev->flags)) { |
2925 | set_bit(R5_Wantwrite, &dev->flags); | |
2926 | set_bit(R5_ReWrite, &dev->flags); | |
2927 | set_bit(R5_LOCKED, &dev->flags); | |
a4456856 | 2928 | s.locked++; |
4e5314b5 N |
2929 | } else { |
2930 | /* let's read it back */ | |
2931 | set_bit(R5_Wantread, &dev->flags); | |
2932 | set_bit(R5_LOCKED, &dev->flags); | |
a4456856 | 2933 | s.locked++; |
4e5314b5 N |
2934 | } |
2935 | } | |
2936 | ||
600aa109 DW |
2937 | /* Finish reconstruct operations initiated by the expansion process */ |
2938 | if (sh->reconstruct_state == reconstruct_state_result) { | |
2939 | sh->reconstruct_state = reconstruct_state_idle; | |
f0a50d37 | 2940 | clear_bit(STRIPE_EXPANDING, &sh->state); |
23397883 | 2941 | for (i = conf->raid_disks; i--; ) { |
ccfcc3c1 | 2942 | set_bit(R5_Wantwrite, &sh->dev[i].flags); |
23397883 | 2943 | set_bit(R5_LOCKED, &sh->dev[i].flags); |
efe31143 | 2944 | s.locked++; |
23397883 | 2945 | } |
f0a50d37 DW |
2946 | } |
2947 | ||
2948 | if (s.expanded && test_bit(STRIPE_EXPANDING, &sh->state) && | |
600aa109 | 2949 | !sh->reconstruct_state) { |
f0a50d37 DW |
2950 | /* Need to write out all blocks after computing parity */ |
2951 | sh->disks = conf->raid_disks; | |
911d4ee8 | 2952 | stripe_set_idx(sh->sector, conf, 0, sh); |
1fe797e6 | 2953 | schedule_reconstruction5(sh, &s, 1, 1); |
600aa109 | 2954 | } else if (s.expanded && !sh->reconstruct_state && s.locked == 0) { |
ccfcc3c1 | 2955 | clear_bit(STRIPE_EXPAND_READY, &sh->state); |
f6705578 | 2956 | atomic_dec(&conf->reshape_stripes); |
ccfcc3c1 N |
2957 | wake_up(&conf->wait_for_overlap); |
2958 | md_done_sync(conf->mddev, STRIPE_SECTORS, 1); | |
2959 | } | |
2960 | ||
0f94e87c | 2961 | if (s.expanding && s.locked == 0 && |
976ea8d4 | 2962 | !test_bit(STRIPE_COMPUTE_RUN, &sh->state)) |
a4456856 | 2963 | handle_stripe_expansion(conf, sh, NULL); |
ccfcc3c1 | 2964 | |
6bfe0b49 | 2965 | unlock: |
1da177e4 LT |
2966 | spin_unlock(&sh->lock); |
2967 | ||
6bfe0b49 DW |
2968 | /* wait for this device to become unblocked */ |
2969 | if (unlikely(blocked_rdev)) | |
2970 | md_wait_for_blocked_rdev(blocked_rdev, conf->mddev); | |
2971 | ||
600aa109 DW |
2972 | if (s.ops_request) |
2973 | raid5_run_ops(sh, s.ops_request); | |
d84e0f10 | 2974 | |
c4e5ac0a | 2975 | ops_run_io(sh, &s); |
1da177e4 | 2976 | |
a4456856 | 2977 | return_io(return_bi); |
df10cfbc DW |
2978 | |
2979 | return blocked_rdev == NULL; | |
1da177e4 LT |
2980 | } |
2981 | ||
df10cfbc | 2982 | static bool handle_stripe6(struct stripe_head *sh, struct page *tmp_page) |
1da177e4 | 2983 | { |
bff61975 | 2984 | raid5_conf_t *conf = sh->raid_conf; |
f416885e | 2985 | int disks = sh->disks; |
a4456856 | 2986 | struct bio *return_bi = NULL; |
34e04e87 | 2987 | int i, pd_idx = sh->pd_idx, qd_idx = sh->qd_idx; |
a4456856 DW |
2988 | struct stripe_head_state s; |
2989 | struct r6_state r6s; | |
16a53ecc | 2990 | struct r5dev *dev, *pdev, *qdev; |
6bfe0b49 | 2991 | mdk_rdev_t *blocked_rdev = NULL; |
1da177e4 | 2992 | |
45b4233c | 2993 | pr_debug("handling stripe %llu, state=%#lx cnt=%d, " |
a4456856 DW |
2994 | "pd_idx=%d, qd_idx=%d\n", |
2995 | (unsigned long long)sh->sector, sh->state, | |
34e04e87 | 2996 | atomic_read(&sh->count), pd_idx, qd_idx); |
a4456856 | 2997 | memset(&s, 0, sizeof(s)); |
72626685 | 2998 | |
16a53ecc N |
2999 | spin_lock(&sh->lock); |
3000 | clear_bit(STRIPE_HANDLE, &sh->state); | |
3001 | clear_bit(STRIPE_DELAYED, &sh->state); | |
3002 | ||
a4456856 DW |
3003 | s.syncing = test_bit(STRIPE_SYNCING, &sh->state); |
3004 | s.expanding = test_bit(STRIPE_EXPAND_SOURCE, &sh->state); | |
3005 | s.expanded = test_bit(STRIPE_EXPAND_READY, &sh->state); | |
16a53ecc | 3006 | /* Now to look around and see what can be done */ |
1da177e4 LT |
3007 | |
3008 | rcu_read_lock(); | |
16a53ecc N |
3009 | for (i=disks; i--; ) { |
3010 | mdk_rdev_t *rdev; | |
3011 | dev = &sh->dev[i]; | |
3012 | clear_bit(R5_Insync, &dev->flags); | |
1da177e4 | 3013 | |
45b4233c | 3014 | pr_debug("check %d: state 0x%lx read %p write %p written %p\n", |
16a53ecc N |
3015 | i, dev->flags, dev->toread, dev->towrite, dev->written); |
3016 | /* maybe we can reply to a read */ | |
3017 | if (test_bit(R5_UPTODATE, &dev->flags) && dev->toread) { | |
3018 | struct bio *rbi, *rbi2; | |
45b4233c | 3019 | pr_debug("Return read for disc %d\n", i); |
16a53ecc N |
3020 | spin_lock_irq(&conf->device_lock); |
3021 | rbi = dev->toread; | |
3022 | dev->toread = NULL; | |
3023 | if (test_and_clear_bit(R5_Overlap, &dev->flags)) | |
3024 | wake_up(&conf->wait_for_overlap); | |
3025 | spin_unlock_irq(&conf->device_lock); | |
3026 | while (rbi && rbi->bi_sector < dev->sector + STRIPE_SECTORS) { | |
3027 | copy_data(0, rbi, dev->page, dev->sector); | |
3028 | rbi2 = r5_next_bio(rbi, dev->sector); | |
3029 | spin_lock_irq(&conf->device_lock); | |
960e739d | 3030 | if (!raid5_dec_bi_phys_segments(rbi)) { |
16a53ecc N |
3031 | rbi->bi_next = return_bi; |
3032 | return_bi = rbi; | |
3033 | } | |
3034 | spin_unlock_irq(&conf->device_lock); | |
3035 | rbi = rbi2; | |
3036 | } | |
3037 | } | |
1da177e4 | 3038 | |
16a53ecc | 3039 | /* now count some things */ |
a4456856 DW |
3040 | if (test_bit(R5_LOCKED, &dev->flags)) s.locked++; |
3041 | if (test_bit(R5_UPTODATE, &dev->flags)) s.uptodate++; | |
1da177e4 | 3042 | |
16a53ecc | 3043 | |
a4456856 DW |
3044 | if (dev->toread) |
3045 | s.to_read++; | |
16a53ecc | 3046 | if (dev->towrite) { |
a4456856 | 3047 | s.to_write++; |
16a53ecc | 3048 | if (!test_bit(R5_OVERWRITE, &dev->flags)) |
a4456856 | 3049 | s.non_overwrite++; |
16a53ecc | 3050 | } |
a4456856 DW |
3051 | if (dev->written) |
3052 | s.written++; | |
16a53ecc | 3053 | rdev = rcu_dereference(conf->disks[i].rdev); |
ac4090d2 N |
3054 | if (blocked_rdev == NULL && |
3055 | rdev && unlikely(test_bit(Blocked, &rdev->flags))) { | |
6bfe0b49 DW |
3056 | blocked_rdev = rdev; |
3057 | atomic_inc(&rdev->nr_pending); | |
6bfe0b49 | 3058 | } |
16a53ecc N |
3059 | if (!rdev || !test_bit(In_sync, &rdev->flags)) { |
3060 | /* The ReadError flag will just be confusing now */ | |
3061 | clear_bit(R5_ReadError, &dev->flags); | |
3062 | clear_bit(R5_ReWrite, &dev->flags); | |
1da177e4 | 3063 | } |
16a53ecc N |
3064 | if (!rdev || !test_bit(In_sync, &rdev->flags) |
3065 | || test_bit(R5_ReadError, &dev->flags)) { | |
a4456856 DW |
3066 | if (s.failed < 2) |
3067 | r6s.failed_num[s.failed] = i; | |
3068 | s.failed++; | |
16a53ecc N |
3069 | } else |
3070 | set_bit(R5_Insync, &dev->flags); | |
1da177e4 LT |
3071 | } |
3072 | rcu_read_unlock(); | |
6bfe0b49 DW |
3073 | |
3074 | if (unlikely(blocked_rdev)) { | |
ac4090d2 N |
3075 | if (s.syncing || s.expanding || s.expanded || |
3076 | s.to_write || s.written) { | |
3077 | set_bit(STRIPE_HANDLE, &sh->state); | |
3078 | goto unlock; | |
3079 | } | |
3080 | /* There is nothing for the blocked_rdev to block */ | |
3081 | rdev_dec_pending(blocked_rdev, conf->mddev); | |
3082 | blocked_rdev = NULL; | |
6bfe0b49 | 3083 | } |
ac4090d2 | 3084 | |
45b4233c | 3085 | pr_debug("locked=%d uptodate=%d to_read=%d" |
16a53ecc | 3086 | " to_write=%d failed=%d failed_num=%d,%d\n", |
a4456856 DW |
3087 | s.locked, s.uptodate, s.to_read, s.to_write, s.failed, |
3088 | r6s.failed_num[0], r6s.failed_num[1]); | |
3089 | /* check if the array has lost >2 devices and, if so, some requests | |
3090 | * might need to be failed | |
16a53ecc | 3091 | */ |
a4456856 | 3092 | if (s.failed > 2 && s.to_read+s.to_write+s.written) |
1fe797e6 | 3093 | handle_failed_stripe(conf, sh, &s, disks, &return_bi); |
a4456856 | 3094 | if (s.failed > 2 && s.syncing) { |
16a53ecc N |
3095 | md_done_sync(conf->mddev, STRIPE_SECTORS,0); |
3096 | clear_bit(STRIPE_SYNCING, &sh->state); | |
a4456856 | 3097 | s.syncing = 0; |
16a53ecc N |
3098 | } |
3099 | ||
3100 | /* | |
3101 | * might be able to return some write requests if the parity blocks | |
3102 | * are safe, or on a failed drive | |
3103 | */ | |
3104 | pdev = &sh->dev[pd_idx]; | |
a4456856 DW |
3105 | r6s.p_failed = (s.failed >= 1 && r6s.failed_num[0] == pd_idx) |
3106 | || (s.failed >= 2 && r6s.failed_num[1] == pd_idx); | |
34e04e87 N |
3107 | qdev = &sh->dev[qd_idx]; |
3108 | r6s.q_failed = (s.failed >= 1 && r6s.failed_num[0] == qd_idx) | |
3109 | || (s.failed >= 2 && r6s.failed_num[1] == qd_idx); | |
a4456856 DW |
3110 | |
3111 | if ( s.written && | |
3112 | ( r6s.p_failed || ((test_bit(R5_Insync, &pdev->flags) | |
16a53ecc | 3113 | && !test_bit(R5_LOCKED, &pdev->flags) |
a4456856 DW |
3114 | && test_bit(R5_UPTODATE, &pdev->flags)))) && |
3115 | ( r6s.q_failed || ((test_bit(R5_Insync, &qdev->flags) | |
16a53ecc | 3116 | && !test_bit(R5_LOCKED, &qdev->flags) |
a4456856 | 3117 | && test_bit(R5_UPTODATE, &qdev->flags))))) |
1fe797e6 | 3118 | handle_stripe_clean_event(conf, sh, disks, &return_bi); |
16a53ecc N |
3119 | |
3120 | /* Now we might consider reading some blocks, either to check/generate | |
3121 | * parity, or to satisfy requests | |
3122 | * or to load a block that is being partially written. | |
3123 | */ | |
a4456856 DW |
3124 | if (s.to_read || s.non_overwrite || (s.to_write && s.failed) || |
3125 | (s.syncing && (s.uptodate < disks)) || s.expanding) | |
1fe797e6 | 3126 | handle_stripe_fill6(sh, &s, &r6s, disks); |
16a53ecc N |
3127 | |
3128 | /* now to consider writing and what else, if anything should be read */ | |
a4456856 | 3129 | if (s.to_write) |
1fe797e6 | 3130 | handle_stripe_dirtying6(conf, sh, &s, &r6s, disks); |
16a53ecc N |
3131 | |
3132 | /* maybe we need to check and possibly fix the parity for this stripe | |
a4456856 DW |
3133 | * Any reads will already have been scheduled, so we just see if enough |
3134 | * data is available | |
16a53ecc | 3135 | */ |
a4456856 DW |
3136 | if (s.syncing && s.locked == 0 && !test_bit(STRIPE_INSYNC, &sh->state)) |
3137 | handle_parity_checks6(conf, sh, &s, &r6s, tmp_page, disks); | |
16a53ecc | 3138 | |
a4456856 | 3139 | if (s.syncing && s.locked == 0 && test_bit(STRIPE_INSYNC, &sh->state)) { |
16a53ecc N |
3140 | md_done_sync(conf->mddev, STRIPE_SECTORS,1); |
3141 | clear_bit(STRIPE_SYNCING, &sh->state); | |
3142 | } | |
3143 | ||
3144 | /* If the failed drives are just a ReadError, then we might need | |
3145 | * to progress the repair/check process | |
3146 | */ | |
a4456856 DW |
3147 | if (s.failed <= 2 && !conf->mddev->ro) |
3148 | for (i = 0; i < s.failed; i++) { | |
3149 | dev = &sh->dev[r6s.failed_num[i]]; | |
16a53ecc N |
3150 | if (test_bit(R5_ReadError, &dev->flags) |
3151 | && !test_bit(R5_LOCKED, &dev->flags) | |
3152 | && test_bit(R5_UPTODATE, &dev->flags) | |
3153 | ) { | |
3154 | if (!test_bit(R5_ReWrite, &dev->flags)) { | |
3155 | set_bit(R5_Wantwrite, &dev->flags); | |
3156 | set_bit(R5_ReWrite, &dev->flags); | |
3157 | set_bit(R5_LOCKED, &dev->flags); | |
3158 | } else { | |
3159 | /* let's read it back */ | |
3160 | set_bit(R5_Wantread, &dev->flags); | |
3161 | set_bit(R5_LOCKED, &dev->flags); | |
3162 | } | |
3163 | } | |
3164 | } | |
f416885e | 3165 | |
a4456856 | 3166 | if (s.expanded && test_bit(STRIPE_EXPANDING, &sh->state)) { |
f416885e N |
3167 | /* Need to write out all blocks after computing P&Q */ |
3168 | sh->disks = conf->raid_disks; | |
911d4ee8 | 3169 | stripe_set_idx(sh->sector, conf, 0, sh); |
f416885e N |
3170 | compute_parity6(sh, RECONSTRUCT_WRITE); |
3171 | for (i = conf->raid_disks ; i-- ; ) { | |
3172 | set_bit(R5_LOCKED, &sh->dev[i].flags); | |
a4456856 | 3173 | s.locked++; |
f416885e N |
3174 | set_bit(R5_Wantwrite, &sh->dev[i].flags); |
3175 | } | |
3176 | clear_bit(STRIPE_EXPANDING, &sh->state); | |
a4456856 | 3177 | } else if (s.expanded) { |
f416885e N |
3178 | clear_bit(STRIPE_EXPAND_READY, &sh->state); |
3179 | atomic_dec(&conf->reshape_stripes); | |
3180 | wake_up(&conf->wait_for_overlap); | |
3181 | md_done_sync(conf->mddev, STRIPE_SECTORS, 1); | |
3182 | } | |
3183 | ||
0f94e87c | 3184 | if (s.expanding && s.locked == 0 && |
976ea8d4 | 3185 | !test_bit(STRIPE_COMPUTE_RUN, &sh->state)) |
a4456856 | 3186 | handle_stripe_expansion(conf, sh, &r6s); |
f416885e | 3187 | |
6bfe0b49 | 3188 | unlock: |
16a53ecc N |
3189 | spin_unlock(&sh->lock); |
3190 | ||
6bfe0b49 DW |
3191 | /* wait for this device to become unblocked */ |
3192 | if (unlikely(blocked_rdev)) | |
3193 | md_wait_for_blocked_rdev(blocked_rdev, conf->mddev); | |
3194 | ||
f0e43bcd | 3195 | ops_run_io(sh, &s); |
16a53ecc | 3196 | |
f0e43bcd | 3197 | return_io(return_bi); |
df10cfbc DW |
3198 | |
3199 | return blocked_rdev == NULL; | |
16a53ecc N |
3200 | } |
3201 | ||
df10cfbc DW |
3202 | /* returns true if the stripe was handled */ |
3203 | static bool handle_stripe(struct stripe_head *sh, struct page *tmp_page) | |
16a53ecc N |
3204 | { |
3205 | if (sh->raid_conf->level == 6) | |
df10cfbc | 3206 | return handle_stripe6(sh, tmp_page); |
16a53ecc | 3207 | else |
df10cfbc | 3208 | return handle_stripe5(sh); |
16a53ecc N |
3209 | } |
3210 | ||
3211 | ||
3212 | ||
3213 | static void raid5_activate_delayed(raid5_conf_t *conf) | |
3214 | { | |
3215 | if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD) { | |
3216 | while (!list_empty(&conf->delayed_list)) { | |
3217 | struct list_head *l = conf->delayed_list.next; | |
3218 | struct stripe_head *sh; | |
3219 | sh = list_entry(l, struct stripe_head, lru); | |
3220 | list_del_init(l); | |
3221 | clear_bit(STRIPE_DELAYED, &sh->state); | |
3222 | if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) | |
3223 | atomic_inc(&conf->preread_active_stripes); | |
8b3e6cdc | 3224 | list_add_tail(&sh->lru, &conf->hold_list); |
16a53ecc | 3225 | } |
6ed3003c N |
3226 | } else |
3227 | blk_plug_device(conf->mddev->queue); | |
16a53ecc N |
3228 | } |
3229 | ||
3230 | static void activate_bit_delay(raid5_conf_t *conf) | |
3231 | { | |
3232 | /* device_lock is held */ | |
3233 | struct list_head head; | |
3234 | list_add(&head, &conf->bitmap_list); | |
3235 | list_del_init(&conf->bitmap_list); | |
3236 | while (!list_empty(&head)) { | |
3237 | struct stripe_head *sh = list_entry(head.next, struct stripe_head, lru); | |
3238 | list_del_init(&sh->lru); | |
3239 | atomic_inc(&sh->count); | |
3240 | __release_stripe(conf, sh); | |
3241 | } | |
3242 | } | |
3243 | ||
3244 | static void unplug_slaves(mddev_t *mddev) | |
3245 | { | |
3246 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
3247 | int i; | |
3248 | ||
3249 | rcu_read_lock(); | |
3250 | for (i=0; i<mddev->raid_disks; i++) { | |
3251 | mdk_rdev_t *rdev = rcu_dereference(conf->disks[i].rdev); | |
3252 | if (rdev && !test_bit(Faulty, &rdev->flags) && atomic_read(&rdev->nr_pending)) { | |
165125e1 | 3253 | struct request_queue *r_queue = bdev_get_queue(rdev->bdev); |
16a53ecc N |
3254 | |
3255 | atomic_inc(&rdev->nr_pending); | |
3256 | rcu_read_unlock(); | |
3257 | ||
2ad8b1ef | 3258 | blk_unplug(r_queue); |
16a53ecc N |
3259 | |
3260 | rdev_dec_pending(rdev, mddev); | |
3261 | rcu_read_lock(); | |
3262 | } | |
3263 | } | |
3264 | rcu_read_unlock(); | |
3265 | } | |
3266 | ||
165125e1 | 3267 | static void raid5_unplug_device(struct request_queue *q) |
16a53ecc N |
3268 | { |
3269 | mddev_t *mddev = q->queuedata; | |
3270 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
3271 | unsigned long flags; | |
3272 | ||
3273 | spin_lock_irqsave(&conf->device_lock, flags); | |
3274 | ||
3275 | if (blk_remove_plug(q)) { | |
3276 | conf->seq_flush++; | |
3277 | raid5_activate_delayed(conf); | |
72626685 | 3278 | } |
1da177e4 LT |
3279 | md_wakeup_thread(mddev->thread); |
3280 | ||
3281 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
3282 | ||
3283 | unplug_slaves(mddev); | |
3284 | } | |
3285 | ||
f022b2fd N |
3286 | static int raid5_congested(void *data, int bits) |
3287 | { | |
3288 | mddev_t *mddev = data; | |
3289 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
3290 | ||
3291 | /* No difference between reads and writes. Just check | |
3292 | * how busy the stripe_cache is | |
3293 | */ | |
3294 | if (conf->inactive_blocked) | |
3295 | return 1; | |
3296 | if (conf->quiesce) | |
3297 | return 1; | |
3298 | if (list_empty_careful(&conf->inactive_list)) | |
3299 | return 1; | |
3300 | ||
3301 | return 0; | |
3302 | } | |
3303 | ||
23032a0e RBJ |
3304 | /* We want read requests to align with chunks where possible, |
3305 | * but write requests don't need to. | |
3306 | */ | |
cc371e66 AK |
3307 | static int raid5_mergeable_bvec(struct request_queue *q, |
3308 | struct bvec_merge_data *bvm, | |
3309 | struct bio_vec *biovec) | |
23032a0e RBJ |
3310 | { |
3311 | mddev_t *mddev = q->queuedata; | |
cc371e66 | 3312 | sector_t sector = bvm->bi_sector + get_start_sect(bvm->bi_bdev); |
23032a0e RBJ |
3313 | int max; |
3314 | unsigned int chunk_sectors = mddev->chunk_size >> 9; | |
cc371e66 | 3315 | unsigned int bio_sectors = bvm->bi_size >> 9; |
23032a0e | 3316 | |
cc371e66 | 3317 | if ((bvm->bi_rw & 1) == WRITE) |
23032a0e RBJ |
3318 | return biovec->bv_len; /* always allow writes to be mergeable */ |
3319 | ||
3320 | max = (chunk_sectors - ((sector & (chunk_sectors - 1)) + bio_sectors)) << 9; | |
3321 | if (max < 0) max = 0; | |
3322 | if (max <= biovec->bv_len && bio_sectors == 0) | |
3323 | return biovec->bv_len; | |
3324 | else | |
3325 | return max; | |
3326 | } | |
3327 | ||
f679623f RBJ |
3328 | |
3329 | static int in_chunk_boundary(mddev_t *mddev, struct bio *bio) | |
3330 | { | |
3331 | sector_t sector = bio->bi_sector + get_start_sect(bio->bi_bdev); | |
3332 | unsigned int chunk_sectors = mddev->chunk_size >> 9; | |
3333 | unsigned int bio_sectors = bio->bi_size >> 9; | |
3334 | ||
3335 | return chunk_sectors >= | |
3336 | ((sector & (chunk_sectors - 1)) + bio_sectors); | |
3337 | } | |
3338 | ||
46031f9a RBJ |
3339 | /* |
3340 | * add bio to the retry LIFO ( in O(1) ... we are in interrupt ) | |
3341 | * later sampled by raid5d. | |
3342 | */ | |
3343 | static void add_bio_to_retry(struct bio *bi,raid5_conf_t *conf) | |
3344 | { | |
3345 | unsigned long flags; | |
3346 | ||
3347 | spin_lock_irqsave(&conf->device_lock, flags); | |
3348 | ||
3349 | bi->bi_next = conf->retry_read_aligned_list; | |
3350 | conf->retry_read_aligned_list = bi; | |
3351 | ||
3352 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
3353 | md_wakeup_thread(conf->mddev->thread); | |
3354 | } | |
3355 | ||
3356 | ||
3357 | static struct bio *remove_bio_from_retry(raid5_conf_t *conf) | |
3358 | { | |
3359 | struct bio *bi; | |
3360 | ||
3361 | bi = conf->retry_read_aligned; | |
3362 | if (bi) { | |
3363 | conf->retry_read_aligned = NULL; | |
3364 | return bi; | |
3365 | } | |
3366 | bi = conf->retry_read_aligned_list; | |
3367 | if(bi) { | |
387bb173 | 3368 | conf->retry_read_aligned_list = bi->bi_next; |
46031f9a | 3369 | bi->bi_next = NULL; |
960e739d JA |
3370 | /* |
3371 | * this sets the active strip count to 1 and the processed | |
3372 | * strip count to zero (upper 8 bits) | |
3373 | */ | |
46031f9a | 3374 | bi->bi_phys_segments = 1; /* biased count of active stripes */ |
46031f9a RBJ |
3375 | } |
3376 | ||
3377 | return bi; | |
3378 | } | |
3379 | ||
3380 | ||
f679623f RBJ |
3381 | /* |
3382 | * The "raid5_align_endio" should check if the read succeeded and if it | |
3383 | * did, call bio_endio on the original bio (having bio_put the new bio | |
3384 | * first). | |
3385 | * If the read failed.. | |
3386 | */ | |
6712ecf8 | 3387 | static void raid5_align_endio(struct bio *bi, int error) |
f679623f RBJ |
3388 | { |
3389 | struct bio* raid_bi = bi->bi_private; | |
46031f9a RBJ |
3390 | mddev_t *mddev; |
3391 | raid5_conf_t *conf; | |
3392 | int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags); | |
3393 | mdk_rdev_t *rdev; | |
3394 | ||
f679623f | 3395 | bio_put(bi); |
46031f9a RBJ |
3396 | |
3397 | mddev = raid_bi->bi_bdev->bd_disk->queue->queuedata; | |
3398 | conf = mddev_to_conf(mddev); | |
3399 | rdev = (void*)raid_bi->bi_next; | |
3400 | raid_bi->bi_next = NULL; | |
3401 | ||
3402 | rdev_dec_pending(rdev, conf->mddev); | |
3403 | ||
3404 | if (!error && uptodate) { | |
6712ecf8 | 3405 | bio_endio(raid_bi, 0); |
46031f9a RBJ |
3406 | if (atomic_dec_and_test(&conf->active_aligned_reads)) |
3407 | wake_up(&conf->wait_for_stripe); | |
6712ecf8 | 3408 | return; |
46031f9a RBJ |
3409 | } |
3410 | ||
3411 | ||
45b4233c | 3412 | pr_debug("raid5_align_endio : io error...handing IO for a retry\n"); |
46031f9a RBJ |
3413 | |
3414 | add_bio_to_retry(raid_bi, conf); | |
f679623f RBJ |
3415 | } |
3416 | ||
387bb173 NB |
3417 | static int bio_fits_rdev(struct bio *bi) |
3418 | { | |
165125e1 | 3419 | struct request_queue *q = bdev_get_queue(bi->bi_bdev); |
387bb173 NB |
3420 | |
3421 | if ((bi->bi_size>>9) > q->max_sectors) | |
3422 | return 0; | |
3423 | blk_recount_segments(q, bi); | |
960e739d | 3424 | if (bi->bi_phys_segments > q->max_phys_segments) |
387bb173 NB |
3425 | return 0; |
3426 | ||
3427 | if (q->merge_bvec_fn) | |
3428 | /* it's too hard to apply the merge_bvec_fn at this stage, | |
3429 | * just just give up | |
3430 | */ | |
3431 | return 0; | |
3432 | ||
3433 | return 1; | |
3434 | } | |
3435 | ||
3436 | ||
165125e1 | 3437 | static int chunk_aligned_read(struct request_queue *q, struct bio * raid_bio) |
f679623f RBJ |
3438 | { |
3439 | mddev_t *mddev = q->queuedata; | |
3440 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
911d4ee8 | 3441 | unsigned int dd_idx; |
f679623f RBJ |
3442 | struct bio* align_bi; |
3443 | mdk_rdev_t *rdev; | |
3444 | ||
3445 | if (!in_chunk_boundary(mddev, raid_bio)) { | |
45b4233c | 3446 | pr_debug("chunk_aligned_read : non aligned\n"); |
f679623f RBJ |
3447 | return 0; |
3448 | } | |
3449 | /* | |
99c0fb5f | 3450 | * use bio_clone to make a copy of the bio |
f679623f RBJ |
3451 | */ |
3452 | align_bi = bio_clone(raid_bio, GFP_NOIO); | |
3453 | if (!align_bi) | |
3454 | return 0; | |
3455 | /* | |
3456 | * set bi_end_io to a new function, and set bi_private to the | |
3457 | * original bio. | |
3458 | */ | |
3459 | align_bi->bi_end_io = raid5_align_endio; | |
3460 | align_bi->bi_private = raid_bio; | |
3461 | /* | |
3462 | * compute position | |
3463 | */ | |
112bf897 N |
3464 | align_bi->bi_sector = raid5_compute_sector(conf, raid_bio->bi_sector, |
3465 | 0, | |
911d4ee8 | 3466 | &dd_idx, NULL); |
f679623f RBJ |
3467 | |
3468 | rcu_read_lock(); | |
3469 | rdev = rcu_dereference(conf->disks[dd_idx].rdev); | |
3470 | if (rdev && test_bit(In_sync, &rdev->flags)) { | |
f679623f RBJ |
3471 | atomic_inc(&rdev->nr_pending); |
3472 | rcu_read_unlock(); | |
46031f9a RBJ |
3473 | raid_bio->bi_next = (void*)rdev; |
3474 | align_bi->bi_bdev = rdev->bdev; | |
3475 | align_bi->bi_flags &= ~(1 << BIO_SEG_VALID); | |
3476 | align_bi->bi_sector += rdev->data_offset; | |
3477 | ||
387bb173 NB |
3478 | if (!bio_fits_rdev(align_bi)) { |
3479 | /* too big in some way */ | |
3480 | bio_put(align_bi); | |
3481 | rdev_dec_pending(rdev, mddev); | |
3482 | return 0; | |
3483 | } | |
3484 | ||
46031f9a RBJ |
3485 | spin_lock_irq(&conf->device_lock); |
3486 | wait_event_lock_irq(conf->wait_for_stripe, | |
3487 | conf->quiesce == 0, | |
3488 | conf->device_lock, /* nothing */); | |
3489 | atomic_inc(&conf->active_aligned_reads); | |
3490 | spin_unlock_irq(&conf->device_lock); | |
3491 | ||
f679623f RBJ |
3492 | generic_make_request(align_bi); |
3493 | return 1; | |
3494 | } else { | |
3495 | rcu_read_unlock(); | |
46031f9a | 3496 | bio_put(align_bi); |
f679623f RBJ |
3497 | return 0; |
3498 | } | |
3499 | } | |
3500 | ||
8b3e6cdc DW |
3501 | /* __get_priority_stripe - get the next stripe to process |
3502 | * | |
3503 | * Full stripe writes are allowed to pass preread active stripes up until | |
3504 | * the bypass_threshold is exceeded. In general the bypass_count | |
3505 | * increments when the handle_list is handled before the hold_list; however, it | |
3506 | * will not be incremented when STRIPE_IO_STARTED is sampled set signifying a | |
3507 | * stripe with in flight i/o. The bypass_count will be reset when the | |
3508 | * head of the hold_list has changed, i.e. the head was promoted to the | |
3509 | * handle_list. | |
3510 | */ | |
3511 | static struct stripe_head *__get_priority_stripe(raid5_conf_t *conf) | |
3512 | { | |
3513 | struct stripe_head *sh; | |
3514 | ||
3515 | pr_debug("%s: handle: %s hold: %s full_writes: %d bypass_count: %d\n", | |
3516 | __func__, | |
3517 | list_empty(&conf->handle_list) ? "empty" : "busy", | |
3518 | list_empty(&conf->hold_list) ? "empty" : "busy", | |
3519 | atomic_read(&conf->pending_full_writes), conf->bypass_count); | |
3520 | ||
3521 | if (!list_empty(&conf->handle_list)) { | |
3522 | sh = list_entry(conf->handle_list.next, typeof(*sh), lru); | |
3523 | ||
3524 | if (list_empty(&conf->hold_list)) | |
3525 | conf->bypass_count = 0; | |
3526 | else if (!test_bit(STRIPE_IO_STARTED, &sh->state)) { | |
3527 | if (conf->hold_list.next == conf->last_hold) | |
3528 | conf->bypass_count++; | |
3529 | else { | |
3530 | conf->last_hold = conf->hold_list.next; | |
3531 | conf->bypass_count -= conf->bypass_threshold; | |
3532 | if (conf->bypass_count < 0) | |
3533 | conf->bypass_count = 0; | |
3534 | } | |
3535 | } | |
3536 | } else if (!list_empty(&conf->hold_list) && | |
3537 | ((conf->bypass_threshold && | |
3538 | conf->bypass_count > conf->bypass_threshold) || | |
3539 | atomic_read(&conf->pending_full_writes) == 0)) { | |
3540 | sh = list_entry(conf->hold_list.next, | |
3541 | typeof(*sh), lru); | |
3542 | conf->bypass_count -= conf->bypass_threshold; | |
3543 | if (conf->bypass_count < 0) | |
3544 | conf->bypass_count = 0; | |
3545 | } else | |
3546 | return NULL; | |
3547 | ||
3548 | list_del_init(&sh->lru); | |
3549 | atomic_inc(&sh->count); | |
3550 | BUG_ON(atomic_read(&sh->count) != 1); | |
3551 | return sh; | |
3552 | } | |
f679623f | 3553 | |
165125e1 | 3554 | static int make_request(struct request_queue *q, struct bio * bi) |
1da177e4 LT |
3555 | { |
3556 | mddev_t *mddev = q->queuedata; | |
3557 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
911d4ee8 | 3558 | int dd_idx; |
1da177e4 LT |
3559 | sector_t new_sector; |
3560 | sector_t logical_sector, last_sector; | |
3561 | struct stripe_head *sh; | |
a362357b | 3562 | const int rw = bio_data_dir(bi); |
c9959059 | 3563 | int cpu, remaining; |
1da177e4 | 3564 | |
e5dcdd80 | 3565 | if (unlikely(bio_barrier(bi))) { |
6712ecf8 | 3566 | bio_endio(bi, -EOPNOTSUPP); |
e5dcdd80 N |
3567 | return 0; |
3568 | } | |
3569 | ||
3d310eb7 | 3570 | md_write_start(mddev, bi); |
06d91a5f | 3571 | |
074a7aca TH |
3572 | cpu = part_stat_lock(); |
3573 | part_stat_inc(cpu, &mddev->gendisk->part0, ios[rw]); | |
3574 | part_stat_add(cpu, &mddev->gendisk->part0, sectors[rw], | |
3575 | bio_sectors(bi)); | |
3576 | part_stat_unlock(); | |
1da177e4 | 3577 | |
802ba064 | 3578 | if (rw == READ && |
52488615 RBJ |
3579 | mddev->reshape_position == MaxSector && |
3580 | chunk_aligned_read(q,bi)) | |
99c0fb5f | 3581 | return 0; |
52488615 | 3582 | |
1da177e4 LT |
3583 | logical_sector = bi->bi_sector & ~((sector_t)STRIPE_SECTORS-1); |
3584 | last_sector = bi->bi_sector + (bi->bi_size>>9); | |
3585 | bi->bi_next = NULL; | |
3586 | bi->bi_phys_segments = 1; /* over-loaded to count active stripes */ | |
06d91a5f | 3587 | |
1da177e4 LT |
3588 | for (;logical_sector < last_sector; logical_sector += STRIPE_SECTORS) { |
3589 | DEFINE_WAIT(w); | |
16a53ecc | 3590 | int disks, data_disks; |
b5663ba4 | 3591 | int previous; |
b578d55f | 3592 | |
7ecaa1e6 | 3593 | retry: |
b5663ba4 | 3594 | previous = 0; |
b578d55f | 3595 | prepare_to_wait(&conf->wait_for_overlap, &w, TASK_UNINTERRUPTIBLE); |
fef9c61f | 3596 | if (likely(conf->reshape_progress == MaxSector)) |
7ecaa1e6 N |
3597 | disks = conf->raid_disks; |
3598 | else { | |
fef9c61f | 3599 | /* spinlock is needed as reshape_progress may be |
df8e7f76 N |
3600 | * 64bit on a 32bit platform, and so it might be |
3601 | * possible to see a half-updated value | |
fef9c61f | 3602 | * Ofcourse reshape_progress could change after |
df8e7f76 N |
3603 | * the lock is dropped, so once we get a reference |
3604 | * to the stripe that we think it is, we will have | |
3605 | * to check again. | |
3606 | */ | |
7ecaa1e6 N |
3607 | spin_lock_irq(&conf->device_lock); |
3608 | disks = conf->raid_disks; | |
fef9c61f N |
3609 | if (mddev->delta_disks < 0 |
3610 | ? logical_sector < conf->reshape_progress | |
3611 | : logical_sector >= conf->reshape_progress) { | |
7ecaa1e6 | 3612 | disks = conf->previous_raid_disks; |
b5663ba4 N |
3613 | previous = 1; |
3614 | } else { | |
fef9c61f N |
3615 | if (mddev->delta_disks < 0 |
3616 | ? logical_sector < conf->reshape_safe | |
3617 | : logical_sector >= conf->reshape_safe) { | |
b578d55f N |
3618 | spin_unlock_irq(&conf->device_lock); |
3619 | schedule(); | |
3620 | goto retry; | |
3621 | } | |
3622 | } | |
7ecaa1e6 N |
3623 | spin_unlock_irq(&conf->device_lock); |
3624 | } | |
16a53ecc N |
3625 | data_disks = disks - conf->max_degraded; |
3626 | ||
112bf897 N |
3627 | new_sector = raid5_compute_sector(conf, logical_sector, |
3628 | previous, | |
911d4ee8 | 3629 | &dd_idx, NULL); |
45b4233c | 3630 | pr_debug("raid5: make_request, sector %llu logical %llu\n", |
1da177e4 LT |
3631 | (unsigned long long)new_sector, |
3632 | (unsigned long long)logical_sector); | |
3633 | ||
b5663ba4 N |
3634 | sh = get_active_stripe(conf, new_sector, previous, |
3635 | (bi->bi_rw&RWA_MASK)); | |
1da177e4 | 3636 | if (sh) { |
fef9c61f | 3637 | if (unlikely(conf->reshape_progress != MaxSector)) { |
7ecaa1e6 | 3638 | /* expansion might have moved on while waiting for a |
df8e7f76 N |
3639 | * stripe, so we must do the range check again. |
3640 | * Expansion could still move past after this | |
3641 | * test, but as we are holding a reference to | |
3642 | * 'sh', we know that if that happens, | |
3643 | * STRIPE_EXPANDING will get set and the expansion | |
3644 | * won't proceed until we finish with the stripe. | |
7ecaa1e6 N |
3645 | */ |
3646 | int must_retry = 0; | |
3647 | spin_lock_irq(&conf->device_lock); | |
fef9c61f N |
3648 | if ((mddev->delta_disks < 0 |
3649 | ? logical_sector >= conf->reshape_progress | |
3650 | : logical_sector < conf->reshape_progress) | |
3651 | && disks == conf->previous_raid_disks) | |
7ecaa1e6 N |
3652 | /* mismatch, need to try again */ |
3653 | must_retry = 1; | |
3654 | spin_unlock_irq(&conf->device_lock); | |
3655 | if (must_retry) { | |
3656 | release_stripe(sh); | |
3657 | goto retry; | |
3658 | } | |
3659 | } | |
e464eafd N |
3660 | /* FIXME what if we get a false positive because these |
3661 | * are being updated. | |
3662 | */ | |
3663 | if (logical_sector >= mddev->suspend_lo && | |
3664 | logical_sector < mddev->suspend_hi) { | |
3665 | release_stripe(sh); | |
3666 | schedule(); | |
3667 | goto retry; | |
3668 | } | |
7ecaa1e6 N |
3669 | |
3670 | if (test_bit(STRIPE_EXPANDING, &sh->state) || | |
3671 | !add_stripe_bio(sh, bi, dd_idx, (bi->bi_rw&RW_MASK))) { | |
3672 | /* Stripe is busy expanding or | |
3673 | * add failed due to overlap. Flush everything | |
1da177e4 LT |
3674 | * and wait a while |
3675 | */ | |
3676 | raid5_unplug_device(mddev->queue); | |
3677 | release_stripe(sh); | |
3678 | schedule(); | |
3679 | goto retry; | |
3680 | } | |
3681 | finish_wait(&conf->wait_for_overlap, &w); | |
6ed3003c N |
3682 | set_bit(STRIPE_HANDLE, &sh->state); |
3683 | clear_bit(STRIPE_DELAYED, &sh->state); | |
1da177e4 | 3684 | release_stripe(sh); |
1da177e4 LT |
3685 | } else { |
3686 | /* cannot get stripe for read-ahead, just give-up */ | |
3687 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
3688 | finish_wait(&conf->wait_for_overlap, &w); | |
3689 | break; | |
3690 | } | |
3691 | ||
3692 | } | |
3693 | spin_lock_irq(&conf->device_lock); | |
960e739d | 3694 | remaining = raid5_dec_bi_phys_segments(bi); |
f6344757 N |
3695 | spin_unlock_irq(&conf->device_lock); |
3696 | if (remaining == 0) { | |
1da177e4 | 3697 | |
16a53ecc | 3698 | if ( rw == WRITE ) |
1da177e4 | 3699 | md_write_end(mddev); |
6712ecf8 | 3700 | |
0e13fe23 | 3701 | bio_endio(bi, 0); |
1da177e4 | 3702 | } |
1da177e4 LT |
3703 | return 0; |
3704 | } | |
3705 | ||
b522adcd DW |
3706 | static sector_t raid5_size(mddev_t *mddev, sector_t sectors, int raid_disks); |
3707 | ||
52c03291 | 3708 | static sector_t reshape_request(mddev_t *mddev, sector_t sector_nr, int *skipped) |
1da177e4 | 3709 | { |
52c03291 N |
3710 | /* reshaping is quite different to recovery/resync so it is |
3711 | * handled quite separately ... here. | |
3712 | * | |
3713 | * On each call to sync_request, we gather one chunk worth of | |
3714 | * destination stripes and flag them as expanding. | |
3715 | * Then we find all the source stripes and request reads. | |
3716 | * As the reads complete, handle_stripe will copy the data | |
3717 | * into the destination stripe and release that stripe. | |
3718 | */ | |
1da177e4 LT |
3719 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; |
3720 | struct stripe_head *sh; | |
ccfcc3c1 | 3721 | sector_t first_sector, last_sector; |
f416885e N |
3722 | int raid_disks = conf->previous_raid_disks; |
3723 | int data_disks = raid_disks - conf->max_degraded; | |
3724 | int new_data_disks = conf->raid_disks - conf->max_degraded; | |
52c03291 N |
3725 | int i; |
3726 | int dd_idx; | |
3727 | sector_t writepos, safepos, gap; | |
ec32a2bd | 3728 | sector_t stripe_addr; |
52c03291 | 3729 | |
fef9c61f N |
3730 | if (sector_nr == 0) { |
3731 | /* If restarting in the middle, skip the initial sectors */ | |
3732 | if (mddev->delta_disks < 0 && | |
3733 | conf->reshape_progress < raid5_size(mddev, 0, 0)) { | |
3734 | sector_nr = raid5_size(mddev, 0, 0) | |
3735 | - conf->reshape_progress; | |
3736 | } else if (mddev->delta_disks > 0 && | |
3737 | conf->reshape_progress > 0) | |
3738 | sector_nr = conf->reshape_progress; | |
f416885e | 3739 | sector_div(sector_nr, new_data_disks); |
fef9c61f N |
3740 | if (sector_nr) { |
3741 | *skipped = 1; | |
3742 | return sector_nr; | |
3743 | } | |
52c03291 N |
3744 | } |
3745 | ||
3746 | /* we update the metadata when there is more than 3Meg | |
3747 | * in the block range (that is rather arbitrary, should | |
3748 | * probably be time based) or when the data about to be | |
3749 | * copied would over-write the source of the data at | |
3750 | * the front of the range. | |
fef9c61f N |
3751 | * i.e. one new_stripe along from reshape_progress new_maps |
3752 | * to after where reshape_safe old_maps to | |
52c03291 | 3753 | */ |
fef9c61f | 3754 | writepos = conf->reshape_progress; |
f416885e | 3755 | sector_div(writepos, new_data_disks); |
fef9c61f | 3756 | safepos = conf->reshape_safe; |
f416885e | 3757 | sector_div(safepos, data_disks); |
fef9c61f N |
3758 | if (mddev->delta_disks < 0) { |
3759 | writepos -= conf->chunk_size/512; | |
3760 | safepos += conf->chunk_size/512; | |
3761 | gap = conf->reshape_safe - conf->reshape_progress; | |
3762 | } else { | |
3763 | writepos += conf->chunk_size/512; | |
3764 | safepos -= conf->chunk_size/512; | |
3765 | gap = conf->reshape_progress - conf->reshape_safe; | |
3766 | } | |
52c03291 | 3767 | |
fef9c61f N |
3768 | if ((mddev->delta_disks < 0 |
3769 | ? writepos < safepos | |
3770 | : writepos > safepos) || | |
f416885e | 3771 | gap > (new_data_disks)*3000*2 /*3Meg*/) { |
52c03291 N |
3772 | /* Cannot proceed until we've updated the superblock... */ |
3773 | wait_event(conf->wait_for_overlap, | |
3774 | atomic_read(&conf->reshape_stripes)==0); | |
fef9c61f | 3775 | mddev->reshape_position = conf->reshape_progress; |
850b2b42 | 3776 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
52c03291 | 3777 | md_wakeup_thread(mddev->thread); |
850b2b42 | 3778 | wait_event(mddev->sb_wait, mddev->flags == 0 || |
52c03291 N |
3779 | kthread_should_stop()); |
3780 | spin_lock_irq(&conf->device_lock); | |
fef9c61f | 3781 | conf->reshape_safe = mddev->reshape_position; |
52c03291 N |
3782 | spin_unlock_irq(&conf->device_lock); |
3783 | wake_up(&conf->wait_for_overlap); | |
3784 | } | |
3785 | ||
ec32a2bd N |
3786 | if (mddev->delta_disks < 0) { |
3787 | BUG_ON(conf->reshape_progress == 0); | |
3788 | stripe_addr = writepos; | |
3789 | BUG_ON((mddev->dev_sectors & | |
3790 | ~((sector_t)mddev->chunk_size / 512 - 1)) | |
3791 | - (conf->chunk_size / 512) - stripe_addr | |
3792 | != sector_nr); | |
3793 | } else { | |
3794 | BUG_ON(writepos != sector_nr + conf->chunk_size / 512); | |
3795 | stripe_addr = sector_nr; | |
3796 | } | |
52c03291 N |
3797 | for (i=0; i < conf->chunk_size/512; i+= STRIPE_SECTORS) { |
3798 | int j; | |
3799 | int skipped = 0; | |
ec32a2bd | 3800 | sh = get_active_stripe(conf, stripe_addr+i, 0, 0); |
52c03291 N |
3801 | set_bit(STRIPE_EXPANDING, &sh->state); |
3802 | atomic_inc(&conf->reshape_stripes); | |
3803 | /* If any of this stripe is beyond the end of the old | |
3804 | * array, then we need to zero those blocks | |
3805 | */ | |
3806 | for (j=sh->disks; j--;) { | |
3807 | sector_t s; | |
3808 | if (j == sh->pd_idx) | |
3809 | continue; | |
f416885e | 3810 | if (conf->level == 6 && |
d0dabf7e | 3811 | j == sh->qd_idx) |
f416885e | 3812 | continue; |
52c03291 | 3813 | s = compute_blocknr(sh, j); |
b522adcd | 3814 | if (s < raid5_size(mddev, 0, 0)) { |
52c03291 N |
3815 | skipped = 1; |
3816 | continue; | |
3817 | } | |
3818 | memset(page_address(sh->dev[j].page), 0, STRIPE_SIZE); | |
3819 | set_bit(R5_Expanded, &sh->dev[j].flags); | |
3820 | set_bit(R5_UPTODATE, &sh->dev[j].flags); | |
3821 | } | |
3822 | if (!skipped) { | |
3823 | set_bit(STRIPE_EXPAND_READY, &sh->state); | |
3824 | set_bit(STRIPE_HANDLE, &sh->state); | |
3825 | } | |
3826 | release_stripe(sh); | |
3827 | } | |
3828 | spin_lock_irq(&conf->device_lock); | |
fef9c61f N |
3829 | if (mddev->delta_disks < 0) |
3830 | conf->reshape_progress -= i * new_data_disks; | |
3831 | else | |
3832 | conf->reshape_progress += i * new_data_disks; | |
52c03291 N |
3833 | spin_unlock_irq(&conf->device_lock); |
3834 | /* Ok, those stripe are ready. We can start scheduling | |
3835 | * reads on the source stripes. | |
3836 | * The source stripes are determined by mapping the first and last | |
3837 | * block on the destination stripes. | |
3838 | */ | |
52c03291 | 3839 | first_sector = |
ec32a2bd | 3840 | raid5_compute_sector(conf, stripe_addr*(new_data_disks), |
911d4ee8 | 3841 | 1, &dd_idx, NULL); |
52c03291 | 3842 | last_sector = |
ec32a2bd | 3843 | raid5_compute_sector(conf, ((stripe_addr+conf->chunk_size/512) |
112bf897 | 3844 | *(new_data_disks) - 1), |
911d4ee8 | 3845 | 1, &dd_idx, NULL); |
58c0fed4 AN |
3846 | if (last_sector >= mddev->dev_sectors) |
3847 | last_sector = mddev->dev_sectors - 1; | |
52c03291 | 3848 | while (first_sector <= last_sector) { |
b5663ba4 | 3849 | sh = get_active_stripe(conf, first_sector, 1, 0); |
52c03291 N |
3850 | set_bit(STRIPE_EXPAND_SOURCE, &sh->state); |
3851 | set_bit(STRIPE_HANDLE, &sh->state); | |
3852 | release_stripe(sh); | |
3853 | first_sector += STRIPE_SECTORS; | |
3854 | } | |
c6207277 N |
3855 | /* If this takes us to the resync_max point where we have to pause, |
3856 | * then we need to write out the superblock. | |
3857 | */ | |
3858 | sector_nr += conf->chunk_size>>9; | |
3859 | if (sector_nr >= mddev->resync_max) { | |
3860 | /* Cannot proceed until we've updated the superblock... */ | |
3861 | wait_event(conf->wait_for_overlap, | |
3862 | atomic_read(&conf->reshape_stripes) == 0); | |
fef9c61f | 3863 | mddev->reshape_position = conf->reshape_progress; |
c6207277 N |
3864 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
3865 | md_wakeup_thread(mddev->thread); | |
3866 | wait_event(mddev->sb_wait, | |
3867 | !test_bit(MD_CHANGE_DEVS, &mddev->flags) | |
3868 | || kthread_should_stop()); | |
3869 | spin_lock_irq(&conf->device_lock); | |
fef9c61f | 3870 | conf->reshape_safe = mddev->reshape_position; |
c6207277 N |
3871 | spin_unlock_irq(&conf->device_lock); |
3872 | wake_up(&conf->wait_for_overlap); | |
3873 | } | |
52c03291 N |
3874 | return conf->chunk_size>>9; |
3875 | } | |
3876 | ||
3877 | /* FIXME go_faster isn't used */ | |
3878 | static inline sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, int go_faster) | |
3879 | { | |
3880 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; | |
3881 | struct stripe_head *sh; | |
58c0fed4 | 3882 | sector_t max_sector = mddev->dev_sectors; |
72626685 | 3883 | int sync_blocks; |
16a53ecc N |
3884 | int still_degraded = 0; |
3885 | int i; | |
1da177e4 | 3886 | |
72626685 | 3887 | if (sector_nr >= max_sector) { |
1da177e4 LT |
3888 | /* just being told to finish up .. nothing much to do */ |
3889 | unplug_slaves(mddev); | |
cea9c228 | 3890 | |
29269553 N |
3891 | if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) { |
3892 | end_reshape(conf); | |
3893 | return 0; | |
3894 | } | |
72626685 N |
3895 | |
3896 | if (mddev->curr_resync < max_sector) /* aborted */ | |
3897 | bitmap_end_sync(mddev->bitmap, mddev->curr_resync, | |
3898 | &sync_blocks, 1); | |
16a53ecc | 3899 | else /* completed sync */ |
72626685 N |
3900 | conf->fullsync = 0; |
3901 | bitmap_close_sync(mddev->bitmap); | |
3902 | ||
1da177e4 LT |
3903 | return 0; |
3904 | } | |
ccfcc3c1 | 3905 | |
52c03291 N |
3906 | if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) |
3907 | return reshape_request(mddev, sector_nr, skipped); | |
f6705578 | 3908 | |
c6207277 N |
3909 | /* No need to check resync_max as we never do more than one |
3910 | * stripe, and as resync_max will always be on a chunk boundary, | |
3911 | * if the check in md_do_sync didn't fire, there is no chance | |
3912 | * of overstepping resync_max here | |
3913 | */ | |
3914 | ||
16a53ecc | 3915 | /* if there is too many failed drives and we are trying |
1da177e4 LT |
3916 | * to resync, then assert that we are finished, because there is |
3917 | * nothing we can do. | |
3918 | */ | |
3285edf1 | 3919 | if (mddev->degraded >= conf->max_degraded && |
16a53ecc | 3920 | test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) { |
58c0fed4 | 3921 | sector_t rv = mddev->dev_sectors - sector_nr; |
57afd89f | 3922 | *skipped = 1; |
1da177e4 LT |
3923 | return rv; |
3924 | } | |
72626685 | 3925 | if (!bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, 1) && |
3855ad9f | 3926 | !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) && |
72626685 N |
3927 | !conf->fullsync && sync_blocks >= STRIPE_SECTORS) { |
3928 | /* we can skip this block, and probably more */ | |
3929 | sync_blocks /= STRIPE_SECTORS; | |
3930 | *skipped = 1; | |
3931 | return sync_blocks * STRIPE_SECTORS; /* keep things rounded to whole stripes */ | |
3932 | } | |
1da177e4 | 3933 | |
b47490c9 N |
3934 | |
3935 | bitmap_cond_end_sync(mddev->bitmap, sector_nr); | |
3936 | ||
b5663ba4 | 3937 | sh = get_active_stripe(conf, sector_nr, 0, 1); |
1da177e4 | 3938 | if (sh == NULL) { |
b5663ba4 | 3939 | sh = get_active_stripe(conf, sector_nr, 0, 0); |
1da177e4 | 3940 | /* make sure we don't swamp the stripe cache if someone else |
16a53ecc | 3941 | * is trying to get access |
1da177e4 | 3942 | */ |
66c006a5 | 3943 | schedule_timeout_uninterruptible(1); |
1da177e4 | 3944 | } |
16a53ecc N |
3945 | /* Need to check if array will still be degraded after recovery/resync |
3946 | * We don't need to check the 'failed' flag as when that gets set, | |
3947 | * recovery aborts. | |
3948 | */ | |
3949 | for (i=0; i<mddev->raid_disks; i++) | |
3950 | if (conf->disks[i].rdev == NULL) | |
3951 | still_degraded = 1; | |
3952 | ||
3953 | bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, still_degraded); | |
3954 | ||
3955 | spin_lock(&sh->lock); | |
1da177e4 LT |
3956 | set_bit(STRIPE_SYNCING, &sh->state); |
3957 | clear_bit(STRIPE_INSYNC, &sh->state); | |
3958 | spin_unlock(&sh->lock); | |
3959 | ||
df10cfbc DW |
3960 | /* wait for any blocked device to be handled */ |
3961 | while(unlikely(!handle_stripe(sh, NULL))) | |
3962 | ; | |
1da177e4 LT |
3963 | release_stripe(sh); |
3964 | ||
3965 | return STRIPE_SECTORS; | |
3966 | } | |
3967 | ||
46031f9a RBJ |
3968 | static int retry_aligned_read(raid5_conf_t *conf, struct bio *raid_bio) |
3969 | { | |
3970 | /* We may not be able to submit a whole bio at once as there | |
3971 | * may not be enough stripe_heads available. | |
3972 | * We cannot pre-allocate enough stripe_heads as we may need | |
3973 | * more than exist in the cache (if we allow ever large chunks). | |
3974 | * So we do one stripe head at a time and record in | |
3975 | * ->bi_hw_segments how many have been done. | |
3976 | * | |
3977 | * We *know* that this entire raid_bio is in one chunk, so | |
3978 | * it will be only one 'dd_idx' and only need one call to raid5_compute_sector. | |
3979 | */ | |
3980 | struct stripe_head *sh; | |
911d4ee8 | 3981 | int dd_idx; |
46031f9a RBJ |
3982 | sector_t sector, logical_sector, last_sector; |
3983 | int scnt = 0; | |
3984 | int remaining; | |
3985 | int handled = 0; | |
3986 | ||
3987 | logical_sector = raid_bio->bi_sector & ~((sector_t)STRIPE_SECTORS-1); | |
112bf897 | 3988 | sector = raid5_compute_sector(conf, logical_sector, |
911d4ee8 | 3989 | 0, &dd_idx, NULL); |
46031f9a RBJ |
3990 | last_sector = raid_bio->bi_sector + (raid_bio->bi_size>>9); |
3991 | ||
3992 | for (; logical_sector < last_sector; | |
387bb173 NB |
3993 | logical_sector += STRIPE_SECTORS, |
3994 | sector += STRIPE_SECTORS, | |
3995 | scnt++) { | |
46031f9a | 3996 | |
960e739d | 3997 | if (scnt < raid5_bi_hw_segments(raid_bio)) |
46031f9a RBJ |
3998 | /* already done this stripe */ |
3999 | continue; | |
4000 | ||
b5663ba4 | 4001 | sh = get_active_stripe(conf, sector, 0, 1); |
46031f9a RBJ |
4002 | |
4003 | if (!sh) { | |
4004 | /* failed to get a stripe - must wait */ | |
960e739d | 4005 | raid5_set_bi_hw_segments(raid_bio, scnt); |
46031f9a RBJ |
4006 | conf->retry_read_aligned = raid_bio; |
4007 | return handled; | |
4008 | } | |
4009 | ||
4010 | set_bit(R5_ReadError, &sh->dev[dd_idx].flags); | |
387bb173 NB |
4011 | if (!add_stripe_bio(sh, raid_bio, dd_idx, 0)) { |
4012 | release_stripe(sh); | |
960e739d | 4013 | raid5_set_bi_hw_segments(raid_bio, scnt); |
387bb173 NB |
4014 | conf->retry_read_aligned = raid_bio; |
4015 | return handled; | |
4016 | } | |
4017 | ||
46031f9a RBJ |
4018 | handle_stripe(sh, NULL); |
4019 | release_stripe(sh); | |
4020 | handled++; | |
4021 | } | |
4022 | spin_lock_irq(&conf->device_lock); | |
960e739d | 4023 | remaining = raid5_dec_bi_phys_segments(raid_bio); |
46031f9a | 4024 | spin_unlock_irq(&conf->device_lock); |
0e13fe23 NB |
4025 | if (remaining == 0) |
4026 | bio_endio(raid_bio, 0); | |
46031f9a RBJ |
4027 | if (atomic_dec_and_test(&conf->active_aligned_reads)) |
4028 | wake_up(&conf->wait_for_stripe); | |
4029 | return handled; | |
4030 | } | |
4031 | ||
4032 | ||
4033 | ||
1da177e4 LT |
4034 | /* |
4035 | * This is our raid5 kernel thread. | |
4036 | * | |
4037 | * We scan the hash table for stripes which can be handled now. | |
4038 | * During the scan, completed stripes are saved for us by the interrupt | |
4039 | * handler, so that they will not have to wait for our next wakeup. | |
4040 | */ | |
6ed3003c | 4041 | static void raid5d(mddev_t *mddev) |
1da177e4 LT |
4042 | { |
4043 | struct stripe_head *sh; | |
4044 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4045 | int handled; | |
4046 | ||
45b4233c | 4047 | pr_debug("+++ raid5d active\n"); |
1da177e4 LT |
4048 | |
4049 | md_check_recovery(mddev); | |
1da177e4 LT |
4050 | |
4051 | handled = 0; | |
4052 | spin_lock_irq(&conf->device_lock); | |
4053 | while (1) { | |
46031f9a | 4054 | struct bio *bio; |
1da177e4 | 4055 | |
ae3c20cc | 4056 | if (conf->seq_flush != conf->seq_write) { |
72626685 | 4057 | int seq = conf->seq_flush; |
700e432d | 4058 | spin_unlock_irq(&conf->device_lock); |
72626685 | 4059 | bitmap_unplug(mddev->bitmap); |
700e432d | 4060 | spin_lock_irq(&conf->device_lock); |
72626685 N |
4061 | conf->seq_write = seq; |
4062 | activate_bit_delay(conf); | |
4063 | } | |
4064 | ||
46031f9a RBJ |
4065 | while ((bio = remove_bio_from_retry(conf))) { |
4066 | int ok; | |
4067 | spin_unlock_irq(&conf->device_lock); | |
4068 | ok = retry_aligned_read(conf, bio); | |
4069 | spin_lock_irq(&conf->device_lock); | |
4070 | if (!ok) | |
4071 | break; | |
4072 | handled++; | |
4073 | } | |
4074 | ||
8b3e6cdc DW |
4075 | sh = __get_priority_stripe(conf); |
4076 | ||
c9f21aaf | 4077 | if (!sh) |
1da177e4 | 4078 | break; |
1da177e4 LT |
4079 | spin_unlock_irq(&conf->device_lock); |
4080 | ||
4081 | handled++; | |
16a53ecc | 4082 | handle_stripe(sh, conf->spare_page); |
1da177e4 LT |
4083 | release_stripe(sh); |
4084 | ||
4085 | spin_lock_irq(&conf->device_lock); | |
4086 | } | |
45b4233c | 4087 | pr_debug("%d stripes handled\n", handled); |
1da177e4 LT |
4088 | |
4089 | spin_unlock_irq(&conf->device_lock); | |
4090 | ||
c9f21aaf | 4091 | async_tx_issue_pending_all(); |
1da177e4 LT |
4092 | unplug_slaves(mddev); |
4093 | ||
45b4233c | 4094 | pr_debug("--- raid5d inactive\n"); |
1da177e4 LT |
4095 | } |
4096 | ||
3f294f4f | 4097 | static ssize_t |
007583c9 | 4098 | raid5_show_stripe_cache_size(mddev_t *mddev, char *page) |
3f294f4f | 4099 | { |
007583c9 | 4100 | raid5_conf_t *conf = mddev_to_conf(mddev); |
96de1e66 N |
4101 | if (conf) |
4102 | return sprintf(page, "%d\n", conf->max_nr_stripes); | |
4103 | else | |
4104 | return 0; | |
3f294f4f N |
4105 | } |
4106 | ||
4107 | static ssize_t | |
007583c9 | 4108 | raid5_store_stripe_cache_size(mddev_t *mddev, const char *page, size_t len) |
3f294f4f | 4109 | { |
007583c9 | 4110 | raid5_conf_t *conf = mddev_to_conf(mddev); |
4ef197d8 | 4111 | unsigned long new; |
b5470dc5 DW |
4112 | int err; |
4113 | ||
3f294f4f N |
4114 | if (len >= PAGE_SIZE) |
4115 | return -EINVAL; | |
96de1e66 N |
4116 | if (!conf) |
4117 | return -ENODEV; | |
3f294f4f | 4118 | |
4ef197d8 | 4119 | if (strict_strtoul(page, 10, &new)) |
3f294f4f N |
4120 | return -EINVAL; |
4121 | if (new <= 16 || new > 32768) | |
4122 | return -EINVAL; | |
4123 | while (new < conf->max_nr_stripes) { | |
4124 | if (drop_one_stripe(conf)) | |
4125 | conf->max_nr_stripes--; | |
4126 | else | |
4127 | break; | |
4128 | } | |
b5470dc5 DW |
4129 | err = md_allow_write(mddev); |
4130 | if (err) | |
4131 | return err; | |
3f294f4f N |
4132 | while (new > conf->max_nr_stripes) { |
4133 | if (grow_one_stripe(conf)) | |
4134 | conf->max_nr_stripes++; | |
4135 | else break; | |
4136 | } | |
4137 | return len; | |
4138 | } | |
007583c9 | 4139 | |
96de1e66 N |
4140 | static struct md_sysfs_entry |
4141 | raid5_stripecache_size = __ATTR(stripe_cache_size, S_IRUGO | S_IWUSR, | |
4142 | raid5_show_stripe_cache_size, | |
4143 | raid5_store_stripe_cache_size); | |
3f294f4f | 4144 | |
8b3e6cdc DW |
4145 | static ssize_t |
4146 | raid5_show_preread_threshold(mddev_t *mddev, char *page) | |
4147 | { | |
4148 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4149 | if (conf) | |
4150 | return sprintf(page, "%d\n", conf->bypass_threshold); | |
4151 | else | |
4152 | return 0; | |
4153 | } | |
4154 | ||
4155 | static ssize_t | |
4156 | raid5_store_preread_threshold(mddev_t *mddev, const char *page, size_t len) | |
4157 | { | |
4158 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4ef197d8 | 4159 | unsigned long new; |
8b3e6cdc DW |
4160 | if (len >= PAGE_SIZE) |
4161 | return -EINVAL; | |
4162 | if (!conf) | |
4163 | return -ENODEV; | |
4164 | ||
4ef197d8 | 4165 | if (strict_strtoul(page, 10, &new)) |
8b3e6cdc | 4166 | return -EINVAL; |
4ef197d8 | 4167 | if (new > conf->max_nr_stripes) |
8b3e6cdc DW |
4168 | return -EINVAL; |
4169 | conf->bypass_threshold = new; | |
4170 | return len; | |
4171 | } | |
4172 | ||
4173 | static struct md_sysfs_entry | |
4174 | raid5_preread_bypass_threshold = __ATTR(preread_bypass_threshold, | |
4175 | S_IRUGO | S_IWUSR, | |
4176 | raid5_show_preread_threshold, | |
4177 | raid5_store_preread_threshold); | |
4178 | ||
3f294f4f | 4179 | static ssize_t |
96de1e66 | 4180 | stripe_cache_active_show(mddev_t *mddev, char *page) |
3f294f4f | 4181 | { |
007583c9 | 4182 | raid5_conf_t *conf = mddev_to_conf(mddev); |
96de1e66 N |
4183 | if (conf) |
4184 | return sprintf(page, "%d\n", atomic_read(&conf->active_stripes)); | |
4185 | else | |
4186 | return 0; | |
3f294f4f N |
4187 | } |
4188 | ||
96de1e66 N |
4189 | static struct md_sysfs_entry |
4190 | raid5_stripecache_active = __ATTR_RO(stripe_cache_active); | |
3f294f4f | 4191 | |
007583c9 | 4192 | static struct attribute *raid5_attrs[] = { |
3f294f4f N |
4193 | &raid5_stripecache_size.attr, |
4194 | &raid5_stripecache_active.attr, | |
8b3e6cdc | 4195 | &raid5_preread_bypass_threshold.attr, |
3f294f4f N |
4196 | NULL, |
4197 | }; | |
007583c9 N |
4198 | static struct attribute_group raid5_attrs_group = { |
4199 | .name = NULL, | |
4200 | .attrs = raid5_attrs, | |
3f294f4f N |
4201 | }; |
4202 | ||
80c3a6ce DW |
4203 | static sector_t |
4204 | raid5_size(mddev_t *mddev, sector_t sectors, int raid_disks) | |
4205 | { | |
4206 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4207 | ||
4208 | if (!sectors) | |
4209 | sectors = mddev->dev_sectors; | |
7ec05478 N |
4210 | if (!raid_disks) { |
4211 | /* size is defined by the smallest of previous and new size */ | |
4212 | if (conf->raid_disks < conf->previous_raid_disks) | |
4213 | raid_disks = conf->raid_disks; | |
4214 | else | |
4215 | raid_disks = conf->previous_raid_disks; | |
4216 | } | |
80c3a6ce DW |
4217 | |
4218 | sectors &= ~((sector_t)mddev->chunk_size/512 - 1); | |
4219 | return sectors * (raid_disks - conf->max_degraded); | |
4220 | } | |
4221 | ||
91adb564 | 4222 | static raid5_conf_t *setup_conf(mddev_t *mddev) |
1da177e4 LT |
4223 | { |
4224 | raid5_conf_t *conf; | |
4225 | int raid_disk, memory; | |
4226 | mdk_rdev_t *rdev; | |
4227 | struct disk_info *disk; | |
1da177e4 | 4228 | |
91adb564 N |
4229 | if (mddev->new_level != 5 |
4230 | && mddev->new_level != 4 | |
4231 | && mddev->new_level != 6) { | |
16a53ecc | 4232 | printk(KERN_ERR "raid5: %s: raid level not set to 4/5/6 (%d)\n", |
91adb564 N |
4233 | mdname(mddev), mddev->new_level); |
4234 | return ERR_PTR(-EIO); | |
1da177e4 | 4235 | } |
91adb564 N |
4236 | if ((mddev->new_level == 5 |
4237 | && !algorithm_valid_raid5(mddev->new_layout)) || | |
4238 | (mddev->new_level == 6 | |
4239 | && !algorithm_valid_raid6(mddev->new_layout))) { | |
99c0fb5f | 4240 | printk(KERN_ERR "raid5: %s: layout %d not supported\n", |
91adb564 N |
4241 | mdname(mddev), mddev->new_layout); |
4242 | return ERR_PTR(-EIO); | |
99c0fb5f | 4243 | } |
91adb564 N |
4244 | if (mddev->new_level == 6 && mddev->raid_disks < 4) { |
4245 | printk(KERN_ERR "raid6: not enough configured devices for %s (%d, minimum 4)\n", | |
4246 | mdname(mddev), mddev->raid_disks); | |
4247 | return ERR_PTR(-EINVAL); | |
4bbf3771 N |
4248 | } |
4249 | ||
91adb564 N |
4250 | if (!mddev->new_chunk || mddev->new_chunk % PAGE_SIZE) { |
4251 | printk(KERN_ERR "raid5: invalid chunk size %d for %s\n", | |
4252 | mddev->new_chunk, mdname(mddev)); | |
4253 | return ERR_PTR(-EINVAL); | |
f6705578 N |
4254 | } |
4255 | ||
91adb564 N |
4256 | conf = kzalloc(sizeof(raid5_conf_t), GFP_KERNEL); |
4257 | if (conf == NULL) | |
1da177e4 | 4258 | goto abort; |
91adb564 N |
4259 | |
4260 | conf->raid_disks = mddev->raid_disks; | |
4261 | if (mddev->reshape_position == MaxSector) | |
4262 | conf->previous_raid_disks = mddev->raid_disks; | |
4263 | else | |
f6705578 | 4264 | conf->previous_raid_disks = mddev->raid_disks - mddev->delta_disks; |
f6705578 N |
4265 | |
4266 | conf->disks = kzalloc(conf->raid_disks * sizeof(struct disk_info), | |
b55e6bfc N |
4267 | GFP_KERNEL); |
4268 | if (!conf->disks) | |
4269 | goto abort; | |
9ffae0cf | 4270 | |
1da177e4 LT |
4271 | conf->mddev = mddev; |
4272 | ||
fccddba0 | 4273 | if ((conf->stripe_hashtbl = kzalloc(PAGE_SIZE, GFP_KERNEL)) == NULL) |
1da177e4 | 4274 | goto abort; |
1da177e4 | 4275 | |
91adb564 | 4276 | if (mddev->new_level == 6) { |
16a53ecc N |
4277 | conf->spare_page = alloc_page(GFP_KERNEL); |
4278 | if (!conf->spare_page) | |
4279 | goto abort; | |
4280 | } | |
1da177e4 LT |
4281 | spin_lock_init(&conf->device_lock); |
4282 | init_waitqueue_head(&conf->wait_for_stripe); | |
4283 | init_waitqueue_head(&conf->wait_for_overlap); | |
4284 | INIT_LIST_HEAD(&conf->handle_list); | |
8b3e6cdc | 4285 | INIT_LIST_HEAD(&conf->hold_list); |
1da177e4 | 4286 | INIT_LIST_HEAD(&conf->delayed_list); |
72626685 | 4287 | INIT_LIST_HEAD(&conf->bitmap_list); |
1da177e4 LT |
4288 | INIT_LIST_HEAD(&conf->inactive_list); |
4289 | atomic_set(&conf->active_stripes, 0); | |
4290 | atomic_set(&conf->preread_active_stripes, 0); | |
46031f9a | 4291 | atomic_set(&conf->active_aligned_reads, 0); |
8b3e6cdc | 4292 | conf->bypass_threshold = BYPASS_THRESHOLD; |
1da177e4 | 4293 | |
45b4233c | 4294 | pr_debug("raid5: run(%s) called.\n", mdname(mddev)); |
1da177e4 | 4295 | |
159ec1fc | 4296 | list_for_each_entry(rdev, &mddev->disks, same_set) { |
1da177e4 | 4297 | raid_disk = rdev->raid_disk; |
f6705578 | 4298 | if (raid_disk >= conf->raid_disks |
1da177e4 LT |
4299 | || raid_disk < 0) |
4300 | continue; | |
4301 | disk = conf->disks + raid_disk; | |
4302 | ||
4303 | disk->rdev = rdev; | |
4304 | ||
b2d444d7 | 4305 | if (test_bit(In_sync, &rdev->flags)) { |
1da177e4 LT |
4306 | char b[BDEVNAME_SIZE]; |
4307 | printk(KERN_INFO "raid5: device %s operational as raid" | |
4308 | " disk %d\n", bdevname(rdev->bdev,b), | |
4309 | raid_disk); | |
8c2e870a NB |
4310 | } else |
4311 | /* Cannot rely on bitmap to complete recovery */ | |
4312 | conf->fullsync = 1; | |
1da177e4 LT |
4313 | } |
4314 | ||
91adb564 N |
4315 | conf->chunk_size = mddev->new_chunk; |
4316 | conf->level = mddev->new_level; | |
16a53ecc N |
4317 | if (conf->level == 6) |
4318 | conf->max_degraded = 2; | |
4319 | else | |
4320 | conf->max_degraded = 1; | |
91adb564 | 4321 | conf->algorithm = mddev->new_layout; |
1da177e4 | 4322 | conf->max_nr_stripes = NR_STRIPES; |
fef9c61f | 4323 | conf->reshape_progress = mddev->reshape_position; |
1da177e4 | 4324 | |
91adb564 N |
4325 | memory = conf->max_nr_stripes * (sizeof(struct stripe_head) + |
4326 | conf->raid_disks * ((sizeof(struct bio) + PAGE_SIZE))) / 1024; | |
4327 | if (grow_stripes(conf, conf->max_nr_stripes)) { | |
4328 | printk(KERN_ERR | |
4329 | "raid5: couldn't allocate %dkB for buffers\n", memory); | |
4330 | goto abort; | |
4331 | } else | |
4332 | printk(KERN_INFO "raid5: allocated %dkB for %s\n", | |
4333 | memory, mdname(mddev)); | |
1da177e4 | 4334 | |
91adb564 N |
4335 | conf->thread = md_register_thread(raid5d, mddev, "%s_raid5"); |
4336 | if (!conf->thread) { | |
4337 | printk(KERN_ERR | |
4338 | "raid5: couldn't allocate thread for %s\n", | |
4339 | mdname(mddev)); | |
16a53ecc N |
4340 | goto abort; |
4341 | } | |
91adb564 N |
4342 | |
4343 | return conf; | |
4344 | ||
4345 | abort: | |
4346 | if (conf) { | |
4347 | shrink_stripes(conf); | |
4348 | safe_put_page(conf->spare_page); | |
4349 | kfree(conf->disks); | |
4350 | kfree(conf->stripe_hashtbl); | |
4351 | kfree(conf); | |
4352 | return ERR_PTR(-EIO); | |
4353 | } else | |
4354 | return ERR_PTR(-ENOMEM); | |
4355 | } | |
4356 | ||
4357 | static int run(mddev_t *mddev) | |
4358 | { | |
4359 | raid5_conf_t *conf; | |
4360 | int working_disks = 0; | |
4361 | mdk_rdev_t *rdev; | |
4362 | ||
4363 | if (mddev->reshape_position != MaxSector) { | |
4364 | /* Check that we can continue the reshape. | |
4365 | * Currently only disks can change, it must | |
4366 | * increase, and we must be past the point where | |
4367 | * a stripe over-writes itself | |
4368 | */ | |
4369 | sector_t here_new, here_old; | |
4370 | int old_disks; | |
18b00334 | 4371 | int max_degraded = (mddev->level == 6 ? 2 : 1); |
91adb564 N |
4372 | |
4373 | if (mddev->new_level != mddev->level || | |
4374 | mddev->new_layout != mddev->layout || | |
4375 | mddev->new_chunk != mddev->chunk_size) { | |
4376 | printk(KERN_ERR "raid5: %s: unsupported reshape " | |
4377 | "required - aborting.\n", | |
4378 | mdname(mddev)); | |
4379 | return -EINVAL; | |
4380 | } | |
91adb564 N |
4381 | old_disks = mddev->raid_disks - mddev->delta_disks; |
4382 | /* reshape_position must be on a new-stripe boundary, and one | |
4383 | * further up in new geometry must map after here in old | |
4384 | * geometry. | |
4385 | */ | |
4386 | here_new = mddev->reshape_position; | |
4387 | if (sector_div(here_new, (mddev->chunk_size>>9)* | |
4388 | (mddev->raid_disks - max_degraded))) { | |
4389 | printk(KERN_ERR "raid5: reshape_position not " | |
4390 | "on a stripe boundary\n"); | |
4391 | return -EINVAL; | |
4392 | } | |
4393 | /* here_new is the stripe we will write to */ | |
4394 | here_old = mddev->reshape_position; | |
4395 | sector_div(here_old, (mddev->chunk_size>>9)* | |
4396 | (old_disks-max_degraded)); | |
4397 | /* here_old is the first stripe that we might need to read | |
4398 | * from */ | |
4399 | if (here_new >= here_old) { | |
4400 | /* Reading from the same stripe as writing to - bad */ | |
4401 | printk(KERN_ERR "raid5: reshape_position too early for " | |
4402 | "auto-recovery - aborting.\n"); | |
4403 | return -EINVAL; | |
4404 | } | |
4405 | printk(KERN_INFO "raid5: reshape will continue\n"); | |
4406 | /* OK, we should be able to continue; */ | |
4407 | } else { | |
4408 | BUG_ON(mddev->level != mddev->new_level); | |
4409 | BUG_ON(mddev->layout != mddev->new_layout); | |
4410 | BUG_ON(mddev->chunk_size != mddev->new_chunk); | |
4411 | BUG_ON(mddev->delta_disks != 0); | |
1da177e4 | 4412 | } |
91adb564 | 4413 | |
245f46c2 N |
4414 | if (mddev->private == NULL) |
4415 | conf = setup_conf(mddev); | |
4416 | else | |
4417 | conf = mddev->private; | |
4418 | ||
91adb564 N |
4419 | if (IS_ERR(conf)) |
4420 | return PTR_ERR(conf); | |
4421 | ||
4422 | mddev->thread = conf->thread; | |
4423 | conf->thread = NULL; | |
4424 | mddev->private = conf; | |
4425 | ||
4426 | /* | |
4427 | * 0 for a fully functional array, 1 or 2 for a degraded array. | |
4428 | */ | |
4429 | list_for_each_entry(rdev, &mddev->disks, same_set) | |
4430 | if (rdev->raid_disk >= 0 && | |
4431 | test_bit(In_sync, &rdev->flags)) | |
4432 | working_disks++; | |
4433 | ||
4434 | mddev->degraded = conf->raid_disks - working_disks; | |
4435 | ||
16a53ecc | 4436 | if (mddev->degraded > conf->max_degraded) { |
1da177e4 LT |
4437 | printk(KERN_ERR "raid5: not enough operational devices for %s" |
4438 | " (%d/%d failed)\n", | |
02c2de8c | 4439 | mdname(mddev), mddev->degraded, conf->raid_disks); |
1da177e4 LT |
4440 | goto abort; |
4441 | } | |
4442 | ||
91adb564 N |
4443 | /* device size must be a multiple of chunk size */ |
4444 | mddev->dev_sectors &= ~(mddev->chunk_size / 512 - 1); | |
4445 | mddev->resync_max_sectors = mddev->dev_sectors; | |
4446 | ||
16a53ecc | 4447 | if (mddev->degraded > 0 && |
1da177e4 | 4448 | mddev->recovery_cp != MaxSector) { |
6ff8d8ec N |
4449 | if (mddev->ok_start_degraded) |
4450 | printk(KERN_WARNING | |
4451 | "raid5: starting dirty degraded array: %s" | |
4452 | "- data corruption possible.\n", | |
4453 | mdname(mddev)); | |
4454 | else { | |
4455 | printk(KERN_ERR | |
4456 | "raid5: cannot start dirty degraded array for %s\n", | |
4457 | mdname(mddev)); | |
4458 | goto abort; | |
4459 | } | |
1da177e4 LT |
4460 | } |
4461 | ||
1da177e4 LT |
4462 | if (mddev->degraded == 0) |
4463 | printk("raid5: raid level %d set %s active with %d out of %d" | |
4464 | " devices, algorithm %d\n", conf->level, mdname(mddev), | |
4465 | mddev->raid_disks-mddev->degraded, mddev->raid_disks, | |
4466 | conf->algorithm); | |
4467 | else | |
4468 | printk(KERN_ALERT "raid5: raid level %d set %s active with %d" | |
4469 | " out of %d devices, algorithm %d\n", conf->level, | |
4470 | mdname(mddev), mddev->raid_disks - mddev->degraded, | |
4471 | mddev->raid_disks, conf->algorithm); | |
4472 | ||
4473 | print_raid5_conf(conf); | |
4474 | ||
fef9c61f | 4475 | if (conf->reshape_progress != MaxSector) { |
f6705578 | 4476 | printk("...ok start reshape thread\n"); |
fef9c61f | 4477 | conf->reshape_safe = conf->reshape_progress; |
f6705578 N |
4478 | atomic_set(&conf->reshape_stripes, 0); |
4479 | clear_bit(MD_RECOVERY_SYNC, &mddev->recovery); | |
4480 | clear_bit(MD_RECOVERY_CHECK, &mddev->recovery); | |
4481 | set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery); | |
4482 | set_bit(MD_RECOVERY_RUNNING, &mddev->recovery); | |
4483 | mddev->sync_thread = md_register_thread(md_do_sync, mddev, | |
4484 | "%s_reshape"); | |
f6705578 N |
4485 | } |
4486 | ||
1da177e4 | 4487 | /* read-ahead size must cover two whole stripes, which is |
16a53ecc | 4488 | * 2 * (datadisks) * chunksize where 'n' is the number of raid devices |
1da177e4 LT |
4489 | */ |
4490 | { | |
16a53ecc N |
4491 | int data_disks = conf->previous_raid_disks - conf->max_degraded; |
4492 | int stripe = data_disks * | |
8932c2e0 | 4493 | (mddev->chunk_size / PAGE_SIZE); |
1da177e4 LT |
4494 | if (mddev->queue->backing_dev_info.ra_pages < 2 * stripe) |
4495 | mddev->queue->backing_dev_info.ra_pages = 2 * stripe; | |
4496 | } | |
4497 | ||
4498 | /* Ok, everything is just fine now */ | |
5e55e2f5 N |
4499 | if (sysfs_create_group(&mddev->kobj, &raid5_attrs_group)) |
4500 | printk(KERN_WARNING | |
4501 | "raid5: failed to create sysfs attributes for %s\n", | |
4502 | mdname(mddev)); | |
7a5febe9 | 4503 | |
91adb564 N |
4504 | mddev->queue->queue_lock = &conf->device_lock; |
4505 | ||
7a5febe9 | 4506 | mddev->queue->unplug_fn = raid5_unplug_device; |
f022b2fd | 4507 | mddev->queue->backing_dev_info.congested_data = mddev; |
041ae52e | 4508 | mddev->queue->backing_dev_info.congested_fn = raid5_congested; |
f022b2fd | 4509 | |
1f403624 | 4510 | md_set_array_sectors(mddev, raid5_size(mddev, 0, 0)); |
7a5febe9 | 4511 | |
23032a0e RBJ |
4512 | blk_queue_merge_bvec(mddev->queue, raid5_mergeable_bvec); |
4513 | ||
1da177e4 LT |
4514 | return 0; |
4515 | abort: | |
e0cf8f04 | 4516 | md_unregister_thread(mddev->thread); |
91adb564 | 4517 | mddev->thread = NULL; |
1da177e4 | 4518 | if (conf) { |
91adb564 | 4519 | shrink_stripes(conf); |
1da177e4 | 4520 | print_raid5_conf(conf); |
16a53ecc | 4521 | safe_put_page(conf->spare_page); |
b55e6bfc | 4522 | kfree(conf->disks); |
fccddba0 | 4523 | kfree(conf->stripe_hashtbl); |
1da177e4 LT |
4524 | kfree(conf); |
4525 | } | |
4526 | mddev->private = NULL; | |
4527 | printk(KERN_ALERT "raid5: failed to run raid set %s\n", mdname(mddev)); | |
4528 | return -EIO; | |
4529 | } | |
4530 | ||
4531 | ||
4532 | ||
3f294f4f | 4533 | static int stop(mddev_t *mddev) |
1da177e4 LT |
4534 | { |
4535 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; | |
4536 | ||
4537 | md_unregister_thread(mddev->thread); | |
4538 | mddev->thread = NULL; | |
4539 | shrink_stripes(conf); | |
fccddba0 | 4540 | kfree(conf->stripe_hashtbl); |
041ae52e | 4541 | mddev->queue->backing_dev_info.congested_fn = NULL; |
1da177e4 | 4542 | blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/ |
007583c9 | 4543 | sysfs_remove_group(&mddev->kobj, &raid5_attrs_group); |
b55e6bfc | 4544 | kfree(conf->disks); |
96de1e66 | 4545 | kfree(conf); |
1da177e4 LT |
4546 | mddev->private = NULL; |
4547 | return 0; | |
4548 | } | |
4549 | ||
45b4233c | 4550 | #ifdef DEBUG |
d710e138 | 4551 | static void print_sh(struct seq_file *seq, struct stripe_head *sh) |
1da177e4 LT |
4552 | { |
4553 | int i; | |
4554 | ||
16a53ecc N |
4555 | seq_printf(seq, "sh %llu, pd_idx %d, state %ld.\n", |
4556 | (unsigned long long)sh->sector, sh->pd_idx, sh->state); | |
4557 | seq_printf(seq, "sh %llu, count %d.\n", | |
4558 | (unsigned long long)sh->sector, atomic_read(&sh->count)); | |
4559 | seq_printf(seq, "sh %llu, ", (unsigned long long)sh->sector); | |
7ecaa1e6 | 4560 | for (i = 0; i < sh->disks; i++) { |
16a53ecc N |
4561 | seq_printf(seq, "(cache%d: %p %ld) ", |
4562 | i, sh->dev[i].page, sh->dev[i].flags); | |
1da177e4 | 4563 | } |
16a53ecc | 4564 | seq_printf(seq, "\n"); |
1da177e4 LT |
4565 | } |
4566 | ||
d710e138 | 4567 | static void printall(struct seq_file *seq, raid5_conf_t *conf) |
1da177e4 LT |
4568 | { |
4569 | struct stripe_head *sh; | |
fccddba0 | 4570 | struct hlist_node *hn; |
1da177e4 LT |
4571 | int i; |
4572 | ||
4573 | spin_lock_irq(&conf->device_lock); | |
4574 | for (i = 0; i < NR_HASH; i++) { | |
fccddba0 | 4575 | hlist_for_each_entry(sh, hn, &conf->stripe_hashtbl[i], hash) { |
1da177e4 LT |
4576 | if (sh->raid_conf != conf) |
4577 | continue; | |
16a53ecc | 4578 | print_sh(seq, sh); |
1da177e4 LT |
4579 | } |
4580 | } | |
4581 | spin_unlock_irq(&conf->device_lock); | |
4582 | } | |
4583 | #endif | |
4584 | ||
d710e138 | 4585 | static void status(struct seq_file *seq, mddev_t *mddev) |
1da177e4 LT |
4586 | { |
4587 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; | |
4588 | int i; | |
4589 | ||
4590 | seq_printf (seq, " level %d, %dk chunk, algorithm %d", mddev->level, mddev->chunk_size >> 10, mddev->layout); | |
02c2de8c | 4591 | seq_printf (seq, " [%d/%d] [", conf->raid_disks, conf->raid_disks - mddev->degraded); |
1da177e4 LT |
4592 | for (i = 0; i < conf->raid_disks; i++) |
4593 | seq_printf (seq, "%s", | |
4594 | conf->disks[i].rdev && | |
b2d444d7 | 4595 | test_bit(In_sync, &conf->disks[i].rdev->flags) ? "U" : "_"); |
1da177e4 | 4596 | seq_printf (seq, "]"); |
45b4233c | 4597 | #ifdef DEBUG |
16a53ecc N |
4598 | seq_printf (seq, "\n"); |
4599 | printall(seq, conf); | |
1da177e4 LT |
4600 | #endif |
4601 | } | |
4602 | ||
4603 | static void print_raid5_conf (raid5_conf_t *conf) | |
4604 | { | |
4605 | int i; | |
4606 | struct disk_info *tmp; | |
4607 | ||
4608 | printk("RAID5 conf printout:\n"); | |
4609 | if (!conf) { | |
4610 | printk("(conf==NULL)\n"); | |
4611 | return; | |
4612 | } | |
02c2de8c N |
4613 | printk(" --- rd:%d wd:%d\n", conf->raid_disks, |
4614 | conf->raid_disks - conf->mddev->degraded); | |
1da177e4 LT |
4615 | |
4616 | for (i = 0; i < conf->raid_disks; i++) { | |
4617 | char b[BDEVNAME_SIZE]; | |
4618 | tmp = conf->disks + i; | |
4619 | if (tmp->rdev) | |
4620 | printk(" disk %d, o:%d, dev:%s\n", | |
b2d444d7 | 4621 | i, !test_bit(Faulty, &tmp->rdev->flags), |
1da177e4 LT |
4622 | bdevname(tmp->rdev->bdev,b)); |
4623 | } | |
4624 | } | |
4625 | ||
4626 | static int raid5_spare_active(mddev_t *mddev) | |
4627 | { | |
4628 | int i; | |
4629 | raid5_conf_t *conf = mddev->private; | |
4630 | struct disk_info *tmp; | |
4631 | ||
4632 | for (i = 0; i < conf->raid_disks; i++) { | |
4633 | tmp = conf->disks + i; | |
4634 | if (tmp->rdev | |
b2d444d7 | 4635 | && !test_bit(Faulty, &tmp->rdev->flags) |
c04be0aa N |
4636 | && !test_and_set_bit(In_sync, &tmp->rdev->flags)) { |
4637 | unsigned long flags; | |
4638 | spin_lock_irqsave(&conf->device_lock, flags); | |
1da177e4 | 4639 | mddev->degraded--; |
c04be0aa | 4640 | spin_unlock_irqrestore(&conf->device_lock, flags); |
1da177e4 LT |
4641 | } |
4642 | } | |
4643 | print_raid5_conf(conf); | |
4644 | return 0; | |
4645 | } | |
4646 | ||
4647 | static int raid5_remove_disk(mddev_t *mddev, int number) | |
4648 | { | |
4649 | raid5_conf_t *conf = mddev->private; | |
4650 | int err = 0; | |
4651 | mdk_rdev_t *rdev; | |
4652 | struct disk_info *p = conf->disks + number; | |
4653 | ||
4654 | print_raid5_conf(conf); | |
4655 | rdev = p->rdev; | |
4656 | if (rdev) { | |
ec32a2bd N |
4657 | if (number >= conf->raid_disks && |
4658 | conf->reshape_progress == MaxSector) | |
4659 | clear_bit(In_sync, &rdev->flags); | |
4660 | ||
b2d444d7 | 4661 | if (test_bit(In_sync, &rdev->flags) || |
1da177e4 LT |
4662 | atomic_read(&rdev->nr_pending)) { |
4663 | err = -EBUSY; | |
4664 | goto abort; | |
4665 | } | |
dfc70645 N |
4666 | /* Only remove non-faulty devices if recovery |
4667 | * isn't possible. | |
4668 | */ | |
4669 | if (!test_bit(Faulty, &rdev->flags) && | |
ec32a2bd N |
4670 | mddev->degraded <= conf->max_degraded && |
4671 | number < conf->raid_disks) { | |
dfc70645 N |
4672 | err = -EBUSY; |
4673 | goto abort; | |
4674 | } | |
1da177e4 | 4675 | p->rdev = NULL; |
fbd568a3 | 4676 | synchronize_rcu(); |
1da177e4 LT |
4677 | if (atomic_read(&rdev->nr_pending)) { |
4678 | /* lost the race, try later */ | |
4679 | err = -EBUSY; | |
4680 | p->rdev = rdev; | |
4681 | } | |
4682 | } | |
4683 | abort: | |
4684 | ||
4685 | print_raid5_conf(conf); | |
4686 | return err; | |
4687 | } | |
4688 | ||
4689 | static int raid5_add_disk(mddev_t *mddev, mdk_rdev_t *rdev) | |
4690 | { | |
4691 | raid5_conf_t *conf = mddev->private; | |
199050ea | 4692 | int err = -EEXIST; |
1da177e4 LT |
4693 | int disk; |
4694 | struct disk_info *p; | |
6c2fce2e NB |
4695 | int first = 0; |
4696 | int last = conf->raid_disks - 1; | |
1da177e4 | 4697 | |
16a53ecc | 4698 | if (mddev->degraded > conf->max_degraded) |
1da177e4 | 4699 | /* no point adding a device */ |
199050ea | 4700 | return -EINVAL; |
1da177e4 | 4701 | |
6c2fce2e NB |
4702 | if (rdev->raid_disk >= 0) |
4703 | first = last = rdev->raid_disk; | |
1da177e4 LT |
4704 | |
4705 | /* | |
16a53ecc N |
4706 | * find the disk ... but prefer rdev->saved_raid_disk |
4707 | * if possible. | |
1da177e4 | 4708 | */ |
16a53ecc | 4709 | if (rdev->saved_raid_disk >= 0 && |
6c2fce2e | 4710 | rdev->saved_raid_disk >= first && |
16a53ecc N |
4711 | conf->disks[rdev->saved_raid_disk].rdev == NULL) |
4712 | disk = rdev->saved_raid_disk; | |
4713 | else | |
6c2fce2e NB |
4714 | disk = first; |
4715 | for ( ; disk <= last ; disk++) | |
1da177e4 | 4716 | if ((p=conf->disks + disk)->rdev == NULL) { |
b2d444d7 | 4717 | clear_bit(In_sync, &rdev->flags); |
1da177e4 | 4718 | rdev->raid_disk = disk; |
199050ea | 4719 | err = 0; |
72626685 N |
4720 | if (rdev->saved_raid_disk != disk) |
4721 | conf->fullsync = 1; | |
d6065f7b | 4722 | rcu_assign_pointer(p->rdev, rdev); |
1da177e4 LT |
4723 | break; |
4724 | } | |
4725 | print_raid5_conf(conf); | |
199050ea | 4726 | return err; |
1da177e4 LT |
4727 | } |
4728 | ||
4729 | static int raid5_resize(mddev_t *mddev, sector_t sectors) | |
4730 | { | |
4731 | /* no resync is happening, and there is enough space | |
4732 | * on all devices, so we can resize. | |
4733 | * We need to make sure resync covers any new space. | |
4734 | * If the array is shrinking we should possibly wait until | |
4735 | * any io in the removed space completes, but it hardly seems | |
4736 | * worth it. | |
4737 | */ | |
4738 | sectors &= ~((sector_t)mddev->chunk_size/512 - 1); | |
1f403624 DW |
4739 | md_set_array_sectors(mddev, raid5_size(mddev, sectors, |
4740 | mddev->raid_disks)); | |
b522adcd DW |
4741 | if (mddev->array_sectors > |
4742 | raid5_size(mddev, sectors, mddev->raid_disks)) | |
4743 | return -EINVAL; | |
f233ea5c | 4744 | set_capacity(mddev->gendisk, mddev->array_sectors); |
44ce6294 | 4745 | mddev->changed = 1; |
58c0fed4 AN |
4746 | if (sectors > mddev->dev_sectors && mddev->recovery_cp == MaxSector) { |
4747 | mddev->recovery_cp = mddev->dev_sectors; | |
1da177e4 LT |
4748 | set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); |
4749 | } | |
58c0fed4 | 4750 | mddev->dev_sectors = sectors; |
4b5c7ae8 | 4751 | mddev->resync_max_sectors = sectors; |
1da177e4 LT |
4752 | return 0; |
4753 | } | |
4754 | ||
29269553 | 4755 | #ifdef CONFIG_MD_RAID5_RESHAPE |
63c70c4f | 4756 | static int raid5_check_reshape(mddev_t *mddev) |
29269553 N |
4757 | { |
4758 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
29269553 | 4759 | |
63c70c4f | 4760 | if (mddev->delta_disks == 0) |
29269553 | 4761 | return 0; /* nothing to do */ |
dba034ee N |
4762 | if (mddev->bitmap) |
4763 | /* Cannot grow a bitmap yet */ | |
4764 | return -EBUSY; | |
ec32a2bd N |
4765 | if (mddev->degraded > conf->max_degraded) |
4766 | return -EINVAL; | |
4767 | if (mddev->delta_disks < 0) { | |
4768 | /* We might be able to shrink, but the devices must | |
4769 | * be made bigger first. | |
4770 | * For raid6, 4 is the minimum size. | |
4771 | * Otherwise 2 is the minimum | |
4772 | */ | |
4773 | int min = 2; | |
4774 | if (mddev->level == 6) | |
4775 | min = 4; | |
4776 | if (mddev->raid_disks + mddev->delta_disks < min) | |
4777 | return -EINVAL; | |
4778 | } | |
29269553 N |
4779 | |
4780 | /* Can only proceed if there are plenty of stripe_heads. | |
4781 | * We need a minimum of one full stripe,, and for sensible progress | |
4782 | * it is best to have about 4 times that. | |
4783 | * If we require 4 times, then the default 256 4K stripe_heads will | |
4784 | * allow for chunk sizes up to 256K, which is probably OK. | |
4785 | * If the chunk size is greater, user-space should request more | |
4786 | * stripe_heads first. | |
4787 | */ | |
63c70c4f N |
4788 | if ((mddev->chunk_size / STRIPE_SIZE) * 4 > conf->max_nr_stripes || |
4789 | (mddev->new_chunk / STRIPE_SIZE) * 4 > conf->max_nr_stripes) { | |
29269553 N |
4790 | printk(KERN_WARNING "raid5: reshape: not enough stripes. Needed %lu\n", |
4791 | (mddev->chunk_size / STRIPE_SIZE)*4); | |
4792 | return -ENOSPC; | |
4793 | } | |
4794 | ||
ec32a2bd | 4795 | return resize_stripes(conf, conf->raid_disks + mddev->delta_disks); |
63c70c4f N |
4796 | } |
4797 | ||
4798 | static int raid5_start_reshape(mddev_t *mddev) | |
4799 | { | |
4800 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4801 | mdk_rdev_t *rdev; | |
63c70c4f N |
4802 | int spares = 0; |
4803 | int added_devices = 0; | |
c04be0aa | 4804 | unsigned long flags; |
63c70c4f | 4805 | |
f416885e | 4806 | if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) |
63c70c4f N |
4807 | return -EBUSY; |
4808 | ||
159ec1fc | 4809 | list_for_each_entry(rdev, &mddev->disks, same_set) |
29269553 N |
4810 | if (rdev->raid_disk < 0 && |
4811 | !test_bit(Faulty, &rdev->flags)) | |
4812 | spares++; | |
63c70c4f | 4813 | |
f416885e | 4814 | if (spares - mddev->degraded < mddev->delta_disks - conf->max_degraded) |
29269553 N |
4815 | /* Not enough devices even to make a degraded array |
4816 | * of that size | |
4817 | */ | |
4818 | return -EINVAL; | |
4819 | ||
ec32a2bd N |
4820 | /* Refuse to reduce size of the array. Any reductions in |
4821 | * array size must be through explicit setting of array_size | |
4822 | * attribute. | |
4823 | */ | |
4824 | if (raid5_size(mddev, 0, conf->raid_disks + mddev->delta_disks) | |
4825 | < mddev->array_sectors) { | |
4826 | printk(KERN_ERR "md: %s: array size must be reduced " | |
4827 | "before number of disks\n", mdname(mddev)); | |
4828 | return -EINVAL; | |
4829 | } | |
4830 | ||
f6705578 | 4831 | atomic_set(&conf->reshape_stripes, 0); |
29269553 N |
4832 | spin_lock_irq(&conf->device_lock); |
4833 | conf->previous_raid_disks = conf->raid_disks; | |
63c70c4f | 4834 | conf->raid_disks += mddev->delta_disks; |
fef9c61f N |
4835 | if (mddev->delta_disks < 0) |
4836 | conf->reshape_progress = raid5_size(mddev, 0, 0); | |
4837 | else | |
4838 | conf->reshape_progress = 0; | |
4839 | conf->reshape_safe = conf->reshape_progress; | |
29269553 N |
4840 | spin_unlock_irq(&conf->device_lock); |
4841 | ||
4842 | /* Add some new drives, as many as will fit. | |
4843 | * We know there are enough to make the newly sized array work. | |
4844 | */ | |
159ec1fc | 4845 | list_for_each_entry(rdev, &mddev->disks, same_set) |
29269553 N |
4846 | if (rdev->raid_disk < 0 && |
4847 | !test_bit(Faulty, &rdev->flags)) { | |
199050ea | 4848 | if (raid5_add_disk(mddev, rdev) == 0) { |
29269553 N |
4849 | char nm[20]; |
4850 | set_bit(In_sync, &rdev->flags); | |
29269553 | 4851 | added_devices++; |
5fd6c1dc | 4852 | rdev->recovery_offset = 0; |
29269553 | 4853 | sprintf(nm, "rd%d", rdev->raid_disk); |
5e55e2f5 N |
4854 | if (sysfs_create_link(&mddev->kobj, |
4855 | &rdev->kobj, nm)) | |
4856 | printk(KERN_WARNING | |
4857 | "raid5: failed to create " | |
4858 | " link %s for %s\n", | |
4859 | nm, mdname(mddev)); | |
29269553 N |
4860 | } else |
4861 | break; | |
4862 | } | |
4863 | ||
ec32a2bd N |
4864 | if (mddev->delta_disks > 0) { |
4865 | spin_lock_irqsave(&conf->device_lock, flags); | |
4866 | mddev->degraded = (conf->raid_disks - conf->previous_raid_disks) | |
4867 | - added_devices; | |
4868 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
4869 | } | |
63c70c4f | 4870 | mddev->raid_disks = conf->raid_disks; |
f6705578 | 4871 | mddev->reshape_position = 0; |
850b2b42 | 4872 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
f6705578 | 4873 | |
29269553 N |
4874 | clear_bit(MD_RECOVERY_SYNC, &mddev->recovery); |
4875 | clear_bit(MD_RECOVERY_CHECK, &mddev->recovery); | |
4876 | set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery); | |
4877 | set_bit(MD_RECOVERY_RUNNING, &mddev->recovery); | |
4878 | mddev->sync_thread = md_register_thread(md_do_sync, mddev, | |
4879 | "%s_reshape"); | |
4880 | if (!mddev->sync_thread) { | |
4881 | mddev->recovery = 0; | |
4882 | spin_lock_irq(&conf->device_lock); | |
4883 | mddev->raid_disks = conf->raid_disks = conf->previous_raid_disks; | |
fef9c61f | 4884 | conf->reshape_progress = MaxSector; |
29269553 N |
4885 | spin_unlock_irq(&conf->device_lock); |
4886 | return -EAGAIN; | |
4887 | } | |
4888 | md_wakeup_thread(mddev->sync_thread); | |
4889 | md_new_event(mddev); | |
4890 | return 0; | |
4891 | } | |
4892 | #endif | |
4893 | ||
ec32a2bd N |
4894 | /* This is called from the reshape thread and should make any |
4895 | * changes needed in 'conf' | |
4896 | */ | |
29269553 N |
4897 | static void end_reshape(raid5_conf_t *conf) |
4898 | { | |
29269553 | 4899 | |
f6705578 | 4900 | if (!test_bit(MD_RECOVERY_INTR, &conf->mddev->recovery)) { |
f6705578 | 4901 | |
f6705578 | 4902 | spin_lock_irq(&conf->device_lock); |
cea9c228 | 4903 | conf->previous_raid_disks = conf->raid_disks; |
fef9c61f | 4904 | conf->reshape_progress = MaxSector; |
f6705578 | 4905 | spin_unlock_irq(&conf->device_lock); |
16a53ecc N |
4906 | |
4907 | /* read-ahead size must cover two whole stripes, which is | |
4908 | * 2 * (datadisks) * chunksize where 'n' is the number of raid devices | |
4909 | */ | |
4910 | { | |
cea9c228 N |
4911 | int data_disks = conf->raid_disks - conf->max_degraded; |
4912 | int stripe = data_disks * (conf->chunk_size | |
4913 | / PAGE_SIZE); | |
16a53ecc N |
4914 | if (conf->mddev->queue->backing_dev_info.ra_pages < 2 * stripe) |
4915 | conf->mddev->queue->backing_dev_info.ra_pages = 2 * stripe; | |
4916 | } | |
29269553 | 4917 | } |
29269553 N |
4918 | } |
4919 | ||
ec32a2bd N |
4920 | /* This is called from the raid5d thread with mddev_lock held. |
4921 | * It makes config changes to the device. | |
4922 | */ | |
cea9c228 N |
4923 | static void raid5_finish_reshape(mddev_t *mddev) |
4924 | { | |
4925 | struct block_device *bdev; | |
4926 | ||
4927 | if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery)) { | |
4928 | ||
ec32a2bd N |
4929 | if (mddev->delta_disks > 0) { |
4930 | md_set_array_sectors(mddev, raid5_size(mddev, 0, 0)); | |
4931 | set_capacity(mddev->gendisk, mddev->array_sectors); | |
4932 | mddev->changed = 1; | |
4933 | ||
4934 | bdev = bdget_disk(mddev->gendisk, 0); | |
4935 | if (bdev) { | |
4936 | mutex_lock(&bdev->bd_inode->i_mutex); | |
4937 | i_size_write(bdev->bd_inode, | |
4938 | (loff_t)mddev->array_sectors << 9); | |
4939 | mutex_unlock(&bdev->bd_inode->i_mutex); | |
4940 | bdput(bdev); | |
4941 | } | |
4942 | } else { | |
4943 | int d; | |
4944 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4945 | mddev->degraded = conf->raid_disks; | |
4946 | for (d = 0; d < conf->raid_disks ; d++) | |
4947 | if (conf->disks[d].rdev && | |
4948 | test_bit(In_sync, | |
4949 | &conf->disks[d].rdev->flags)) | |
4950 | mddev->degraded--; | |
4951 | for (d = conf->raid_disks ; | |
4952 | d < conf->raid_disks - mddev->delta_disks; | |
4953 | d++) | |
4954 | raid5_remove_disk(mddev, d); | |
cea9c228 | 4955 | } |
ec32a2bd N |
4956 | mddev->reshape_position = MaxSector; |
4957 | mddev->delta_disks = 0; | |
cea9c228 N |
4958 | } |
4959 | } | |
4960 | ||
72626685 N |
4961 | static void raid5_quiesce(mddev_t *mddev, int state) |
4962 | { | |
4963 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4964 | ||
4965 | switch(state) { | |
e464eafd N |
4966 | case 2: /* resume for a suspend */ |
4967 | wake_up(&conf->wait_for_overlap); | |
4968 | break; | |
4969 | ||
72626685 N |
4970 | case 1: /* stop all writes */ |
4971 | spin_lock_irq(&conf->device_lock); | |
4972 | conf->quiesce = 1; | |
4973 | wait_event_lock_irq(conf->wait_for_stripe, | |
46031f9a RBJ |
4974 | atomic_read(&conf->active_stripes) == 0 && |
4975 | atomic_read(&conf->active_aligned_reads) == 0, | |
72626685 N |
4976 | conf->device_lock, /* nothing */); |
4977 | spin_unlock_irq(&conf->device_lock); | |
4978 | break; | |
4979 | ||
4980 | case 0: /* re-enable writes */ | |
4981 | spin_lock_irq(&conf->device_lock); | |
4982 | conf->quiesce = 0; | |
4983 | wake_up(&conf->wait_for_stripe); | |
e464eafd | 4984 | wake_up(&conf->wait_for_overlap); |
72626685 N |
4985 | spin_unlock_irq(&conf->device_lock); |
4986 | break; | |
4987 | } | |
72626685 | 4988 | } |
b15c2e57 | 4989 | |
d562b0c4 N |
4990 | |
4991 | static void *raid5_takeover_raid1(mddev_t *mddev) | |
4992 | { | |
4993 | int chunksect; | |
4994 | ||
4995 | if (mddev->raid_disks != 2 || | |
4996 | mddev->degraded > 1) | |
4997 | return ERR_PTR(-EINVAL); | |
4998 | ||
4999 | /* Should check if there are write-behind devices? */ | |
5000 | ||
5001 | chunksect = 64*2; /* 64K by default */ | |
5002 | ||
5003 | /* The array must be an exact multiple of chunksize */ | |
5004 | while (chunksect && (mddev->array_sectors & (chunksect-1))) | |
5005 | chunksect >>= 1; | |
5006 | ||
5007 | if ((chunksect<<9) < STRIPE_SIZE) | |
5008 | /* array size does not allow a suitable chunk size */ | |
5009 | return ERR_PTR(-EINVAL); | |
5010 | ||
5011 | mddev->new_level = 5; | |
5012 | mddev->new_layout = ALGORITHM_LEFT_SYMMETRIC; | |
5013 | mddev->new_chunk = chunksect << 9; | |
5014 | ||
5015 | return setup_conf(mddev); | |
5016 | } | |
5017 | ||
fc9739c6 N |
5018 | static void *raid5_takeover_raid6(mddev_t *mddev) |
5019 | { | |
5020 | int new_layout; | |
5021 | ||
5022 | switch (mddev->layout) { | |
5023 | case ALGORITHM_LEFT_ASYMMETRIC_6: | |
5024 | new_layout = ALGORITHM_LEFT_ASYMMETRIC; | |
5025 | break; | |
5026 | case ALGORITHM_RIGHT_ASYMMETRIC_6: | |
5027 | new_layout = ALGORITHM_RIGHT_ASYMMETRIC; | |
5028 | break; | |
5029 | case ALGORITHM_LEFT_SYMMETRIC_6: | |
5030 | new_layout = ALGORITHM_LEFT_SYMMETRIC; | |
5031 | break; | |
5032 | case ALGORITHM_RIGHT_SYMMETRIC_6: | |
5033 | new_layout = ALGORITHM_RIGHT_SYMMETRIC; | |
5034 | break; | |
5035 | case ALGORITHM_PARITY_0_6: | |
5036 | new_layout = ALGORITHM_PARITY_0; | |
5037 | break; | |
5038 | case ALGORITHM_PARITY_N: | |
5039 | new_layout = ALGORITHM_PARITY_N; | |
5040 | break; | |
5041 | default: | |
5042 | return ERR_PTR(-EINVAL); | |
5043 | } | |
5044 | mddev->new_level = 5; | |
5045 | mddev->new_layout = new_layout; | |
5046 | mddev->delta_disks = -1; | |
5047 | mddev->raid_disks -= 1; | |
5048 | return setup_conf(mddev); | |
5049 | } | |
5050 | ||
d562b0c4 | 5051 | |
b3546035 N |
5052 | static int raid5_reconfig(mddev_t *mddev, int new_layout, int new_chunk) |
5053 | { | |
5054 | /* Currently the layout and chunk size can only be changed | |
5055 | * for a 2-drive raid array, as in that case no data shuffling | |
5056 | * is required. | |
5057 | * Later we might validate these and set new_* so a reshape | |
5058 | * can complete the change. | |
5059 | */ | |
5060 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
5061 | ||
5062 | if (new_layout >= 0 && !algorithm_valid_raid5(new_layout)) | |
5063 | return -EINVAL; | |
5064 | if (new_chunk > 0) { | |
5065 | if (new_chunk & (new_chunk-1)) | |
5066 | /* not a power of 2 */ | |
5067 | return -EINVAL; | |
5068 | if (new_chunk < PAGE_SIZE) | |
5069 | return -EINVAL; | |
5070 | if (mddev->array_sectors & ((new_chunk>>9)-1)) | |
5071 | /* not factor of array size */ | |
5072 | return -EINVAL; | |
5073 | } | |
5074 | ||
5075 | /* They look valid */ | |
5076 | ||
5077 | if (mddev->raid_disks != 2) | |
5078 | return -EINVAL; | |
5079 | ||
5080 | if (new_layout >= 0) { | |
5081 | conf->algorithm = new_layout; | |
5082 | mddev->layout = mddev->new_layout = new_layout; | |
5083 | } | |
5084 | if (new_chunk > 0) { | |
5085 | conf->chunk_size = new_chunk; | |
5086 | mddev->chunk_size = mddev->new_chunk = new_chunk; | |
5087 | } | |
5088 | set_bit(MD_CHANGE_DEVS, &mddev->flags); | |
5089 | md_wakeup_thread(mddev->thread); | |
5090 | return 0; | |
5091 | } | |
5092 | ||
d562b0c4 N |
5093 | static void *raid5_takeover(mddev_t *mddev) |
5094 | { | |
5095 | /* raid5 can take over: | |
5096 | * raid0 - if all devices are the same - make it a raid4 layout | |
5097 | * raid1 - if there are two drives. We need to know the chunk size | |
5098 | * raid4 - trivial - just use a raid4 layout. | |
5099 | * raid6 - Providing it is a *_6 layout | |
5100 | * | |
5101 | * For now, just do raid1 | |
5102 | */ | |
5103 | ||
5104 | if (mddev->level == 1) | |
5105 | return raid5_takeover_raid1(mddev); | |
e9d4758f N |
5106 | if (mddev->level == 4) { |
5107 | mddev->new_layout = ALGORITHM_PARITY_N; | |
5108 | mddev->new_level = 5; | |
5109 | return setup_conf(mddev); | |
5110 | } | |
fc9739c6 N |
5111 | if (mddev->level == 6) |
5112 | return raid5_takeover_raid6(mddev); | |
d562b0c4 N |
5113 | |
5114 | return ERR_PTR(-EINVAL); | |
5115 | } | |
5116 | ||
5117 | ||
245f46c2 N |
5118 | static struct mdk_personality raid5_personality; |
5119 | ||
5120 | static void *raid6_takeover(mddev_t *mddev) | |
5121 | { | |
5122 | /* Currently can only take over a raid5. We map the | |
5123 | * personality to an equivalent raid6 personality | |
5124 | * with the Q block at the end. | |
5125 | */ | |
5126 | int new_layout; | |
5127 | ||
5128 | if (mddev->pers != &raid5_personality) | |
5129 | return ERR_PTR(-EINVAL); | |
5130 | if (mddev->degraded > 1) | |
5131 | return ERR_PTR(-EINVAL); | |
5132 | if (mddev->raid_disks > 253) | |
5133 | return ERR_PTR(-EINVAL); | |
5134 | if (mddev->raid_disks < 3) | |
5135 | return ERR_PTR(-EINVAL); | |
5136 | ||
5137 | switch (mddev->layout) { | |
5138 | case ALGORITHM_LEFT_ASYMMETRIC: | |
5139 | new_layout = ALGORITHM_LEFT_ASYMMETRIC_6; | |
5140 | break; | |
5141 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
5142 | new_layout = ALGORITHM_RIGHT_ASYMMETRIC_6; | |
5143 | break; | |
5144 | case ALGORITHM_LEFT_SYMMETRIC: | |
5145 | new_layout = ALGORITHM_LEFT_SYMMETRIC_6; | |
5146 | break; | |
5147 | case ALGORITHM_RIGHT_SYMMETRIC: | |
5148 | new_layout = ALGORITHM_RIGHT_SYMMETRIC_6; | |
5149 | break; | |
5150 | case ALGORITHM_PARITY_0: | |
5151 | new_layout = ALGORITHM_PARITY_0_6; | |
5152 | break; | |
5153 | case ALGORITHM_PARITY_N: | |
5154 | new_layout = ALGORITHM_PARITY_N; | |
5155 | break; | |
5156 | default: | |
5157 | return ERR_PTR(-EINVAL); | |
5158 | } | |
5159 | mddev->new_level = 6; | |
5160 | mddev->new_layout = new_layout; | |
5161 | mddev->delta_disks = 1; | |
5162 | mddev->raid_disks += 1; | |
5163 | return setup_conf(mddev); | |
5164 | } | |
5165 | ||
5166 | ||
16a53ecc N |
5167 | static struct mdk_personality raid6_personality = |
5168 | { | |
5169 | .name = "raid6", | |
5170 | .level = 6, | |
5171 | .owner = THIS_MODULE, | |
5172 | .make_request = make_request, | |
5173 | .run = run, | |
5174 | .stop = stop, | |
5175 | .status = status, | |
5176 | .error_handler = error, | |
5177 | .hot_add_disk = raid5_add_disk, | |
5178 | .hot_remove_disk= raid5_remove_disk, | |
5179 | .spare_active = raid5_spare_active, | |
5180 | .sync_request = sync_request, | |
5181 | .resize = raid5_resize, | |
80c3a6ce | 5182 | .size = raid5_size, |
f416885e N |
5183 | #ifdef CONFIG_MD_RAID5_RESHAPE |
5184 | .check_reshape = raid5_check_reshape, | |
5185 | .start_reshape = raid5_start_reshape, | |
cea9c228 | 5186 | .finish_reshape = raid5_finish_reshape, |
f416885e | 5187 | #endif |
16a53ecc | 5188 | .quiesce = raid5_quiesce, |
245f46c2 | 5189 | .takeover = raid6_takeover, |
16a53ecc | 5190 | }; |
2604b703 | 5191 | static struct mdk_personality raid5_personality = |
1da177e4 LT |
5192 | { |
5193 | .name = "raid5", | |
2604b703 | 5194 | .level = 5, |
1da177e4 LT |
5195 | .owner = THIS_MODULE, |
5196 | .make_request = make_request, | |
5197 | .run = run, | |
5198 | .stop = stop, | |
5199 | .status = status, | |
5200 | .error_handler = error, | |
5201 | .hot_add_disk = raid5_add_disk, | |
5202 | .hot_remove_disk= raid5_remove_disk, | |
5203 | .spare_active = raid5_spare_active, | |
5204 | .sync_request = sync_request, | |
5205 | .resize = raid5_resize, | |
80c3a6ce | 5206 | .size = raid5_size, |
29269553 | 5207 | #ifdef CONFIG_MD_RAID5_RESHAPE |
63c70c4f N |
5208 | .check_reshape = raid5_check_reshape, |
5209 | .start_reshape = raid5_start_reshape, | |
cea9c228 | 5210 | .finish_reshape = raid5_finish_reshape, |
29269553 | 5211 | #endif |
72626685 | 5212 | .quiesce = raid5_quiesce, |
d562b0c4 | 5213 | .takeover = raid5_takeover, |
b3546035 | 5214 | .reconfig = raid5_reconfig, |
1da177e4 LT |
5215 | }; |
5216 | ||
2604b703 | 5217 | static struct mdk_personality raid4_personality = |
1da177e4 | 5218 | { |
2604b703 N |
5219 | .name = "raid4", |
5220 | .level = 4, | |
5221 | .owner = THIS_MODULE, | |
5222 | .make_request = make_request, | |
5223 | .run = run, | |
5224 | .stop = stop, | |
5225 | .status = status, | |
5226 | .error_handler = error, | |
5227 | .hot_add_disk = raid5_add_disk, | |
5228 | .hot_remove_disk= raid5_remove_disk, | |
5229 | .spare_active = raid5_spare_active, | |
5230 | .sync_request = sync_request, | |
5231 | .resize = raid5_resize, | |
80c3a6ce | 5232 | .size = raid5_size, |
3d37890b N |
5233 | #ifdef CONFIG_MD_RAID5_RESHAPE |
5234 | .check_reshape = raid5_check_reshape, | |
5235 | .start_reshape = raid5_start_reshape, | |
cea9c228 | 5236 | .finish_reshape = raid5_finish_reshape, |
3d37890b | 5237 | #endif |
2604b703 N |
5238 | .quiesce = raid5_quiesce, |
5239 | }; | |
5240 | ||
5241 | static int __init raid5_init(void) | |
5242 | { | |
16a53ecc | 5243 | register_md_personality(&raid6_personality); |
2604b703 N |
5244 | register_md_personality(&raid5_personality); |
5245 | register_md_personality(&raid4_personality); | |
5246 | return 0; | |
1da177e4 LT |
5247 | } |
5248 | ||
2604b703 | 5249 | static void raid5_exit(void) |
1da177e4 | 5250 | { |
16a53ecc | 5251 | unregister_md_personality(&raid6_personality); |
2604b703 N |
5252 | unregister_md_personality(&raid5_personality); |
5253 | unregister_md_personality(&raid4_personality); | |
1da177e4 LT |
5254 | } |
5255 | ||
5256 | module_init(raid5_init); | |
5257 | module_exit(raid5_exit); | |
5258 | MODULE_LICENSE("GPL"); | |
5259 | MODULE_ALIAS("md-personality-4"); /* RAID5 */ | |
d9d166c2 N |
5260 | MODULE_ALIAS("md-raid5"); |
5261 | MODULE_ALIAS("md-raid4"); | |
2604b703 N |
5262 | MODULE_ALIAS("md-level-5"); |
5263 | MODULE_ALIAS("md-level-4"); | |
16a53ecc N |
5264 | MODULE_ALIAS("md-personality-8"); /* RAID6 */ |
5265 | MODULE_ALIAS("md-raid6"); | |
5266 | MODULE_ALIAS("md-level-6"); | |
5267 | ||
5268 | /* This used to be two separate modules, they were: */ | |
5269 | MODULE_ALIAS("raid5"); | |
5270 | MODULE_ALIAS("raid6"); |