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 | |
1da177e4 LT |
46 | #include <linux/module.h> |
47 | #include <linux/slab.h> | |
1da177e4 LT |
48 | #include <linux/highmem.h> |
49 | #include <linux/bitops.h> | |
f6705578 | 50 | #include <linux/kthread.h> |
1da177e4 | 51 | #include <asm/atomic.h> |
16a53ecc | 52 | #include "raid6.h" |
1da177e4 | 53 | |
72626685 N |
54 | #include <linux/raid/bitmap.h> |
55 | ||
1da177e4 LT |
56 | /* |
57 | * Stripe cache | |
58 | */ | |
59 | ||
60 | #define NR_STRIPES 256 | |
61 | #define STRIPE_SIZE PAGE_SIZE | |
62 | #define STRIPE_SHIFT (PAGE_SHIFT - 9) | |
63 | #define STRIPE_SECTORS (STRIPE_SIZE>>9) | |
64 | #define IO_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 | */ | |
83 | #define RAID5_DEBUG 0 | |
84 | #define RAID5_PARANOIA 1 | |
85 | #if RAID5_PARANOIA && defined(CONFIG_SMP) | |
86 | # define CHECK_DEVLOCK() assert_spin_locked(&conf->device_lock) | |
87 | #else | |
88 | # define CHECK_DEVLOCK() | |
89 | #endif | |
90 | ||
91 | #define PRINTK(x...) ((void)(RAID5_DEBUG && printk(x))) | |
92 | #if RAID5_DEBUG | |
93 | #define inline | |
94 | #define __inline__ | |
95 | #endif | |
96 | ||
16a53ecc N |
97 | #if !RAID6_USE_EMPTY_ZERO_PAGE |
98 | /* In .bss so it's zeroed */ | |
99 | const char raid6_empty_zero_page[PAGE_SIZE] __attribute__((aligned(256))); | |
100 | #endif | |
101 | ||
102 | static inline int raid6_next_disk(int disk, int raid_disks) | |
103 | { | |
104 | disk++; | |
105 | return (disk < raid_disks) ? disk : 0; | |
106 | } | |
1da177e4 LT |
107 | static void print_raid5_conf (raid5_conf_t *conf); |
108 | ||
858119e1 | 109 | static void __release_stripe(raid5_conf_t *conf, struct stripe_head *sh) |
1da177e4 LT |
110 | { |
111 | if (atomic_dec_and_test(&sh->count)) { | |
78bafebd ES |
112 | BUG_ON(!list_empty(&sh->lru)); |
113 | BUG_ON(atomic_read(&conf->active_stripes)==0); | |
1da177e4 | 114 | if (test_bit(STRIPE_HANDLE, &sh->state)) { |
7c785b7a | 115 | if (test_bit(STRIPE_DELAYED, &sh->state)) { |
1da177e4 | 116 | list_add_tail(&sh->lru, &conf->delayed_list); |
7c785b7a N |
117 | blk_plug_device(conf->mddev->queue); |
118 | } else if (test_bit(STRIPE_BIT_DELAY, &sh->state) && | |
ae3c20cc | 119 | sh->bm_seq - conf->seq_write > 0) { |
72626685 | 120 | list_add_tail(&sh->lru, &conf->bitmap_list); |
7c785b7a N |
121 | blk_plug_device(conf->mddev->queue); |
122 | } else { | |
72626685 | 123 | clear_bit(STRIPE_BIT_DELAY, &sh->state); |
1da177e4 | 124 | list_add_tail(&sh->lru, &conf->handle_list); |
72626685 | 125 | } |
1da177e4 LT |
126 | md_wakeup_thread(conf->mddev->thread); |
127 | } else { | |
128 | if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
129 | atomic_dec(&conf->preread_active_stripes); | |
130 | if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD) | |
131 | md_wakeup_thread(conf->mddev->thread); | |
132 | } | |
1da177e4 | 133 | atomic_dec(&conf->active_stripes); |
ccfcc3c1 N |
134 | if (!test_bit(STRIPE_EXPANDING, &sh->state)) { |
135 | list_add_tail(&sh->lru, &conf->inactive_list); | |
1da177e4 | 136 | wake_up(&conf->wait_for_stripe); |
46031f9a RBJ |
137 | if (conf->retry_read_aligned) |
138 | md_wakeup_thread(conf->mddev->thread); | |
ccfcc3c1 | 139 | } |
1da177e4 LT |
140 | } |
141 | } | |
142 | } | |
143 | static void release_stripe(struct stripe_head *sh) | |
144 | { | |
145 | raid5_conf_t *conf = sh->raid_conf; | |
146 | unsigned long flags; | |
16a53ecc | 147 | |
1da177e4 LT |
148 | spin_lock_irqsave(&conf->device_lock, flags); |
149 | __release_stripe(conf, sh); | |
150 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
151 | } | |
152 | ||
fccddba0 | 153 | static inline void remove_hash(struct stripe_head *sh) |
1da177e4 LT |
154 | { |
155 | PRINTK("remove_hash(), stripe %llu\n", (unsigned long long)sh->sector); | |
156 | ||
fccddba0 | 157 | hlist_del_init(&sh->hash); |
1da177e4 LT |
158 | } |
159 | ||
16a53ecc | 160 | static inline void insert_hash(raid5_conf_t *conf, struct stripe_head *sh) |
1da177e4 | 161 | { |
fccddba0 | 162 | struct hlist_head *hp = stripe_hash(conf, sh->sector); |
1da177e4 LT |
163 | |
164 | PRINTK("insert_hash(), stripe %llu\n", (unsigned long long)sh->sector); | |
165 | ||
166 | CHECK_DEVLOCK(); | |
fccddba0 | 167 | hlist_add_head(&sh->hash, hp); |
1da177e4 LT |
168 | } |
169 | ||
170 | ||
171 | /* find an idle stripe, make sure it is unhashed, and return it. */ | |
172 | static struct stripe_head *get_free_stripe(raid5_conf_t *conf) | |
173 | { | |
174 | struct stripe_head *sh = NULL; | |
175 | struct list_head *first; | |
176 | ||
177 | CHECK_DEVLOCK(); | |
178 | if (list_empty(&conf->inactive_list)) | |
179 | goto out; | |
180 | first = conf->inactive_list.next; | |
181 | sh = list_entry(first, struct stripe_head, lru); | |
182 | list_del_init(first); | |
183 | remove_hash(sh); | |
184 | atomic_inc(&conf->active_stripes); | |
185 | out: | |
186 | return sh; | |
187 | } | |
188 | ||
189 | static void shrink_buffers(struct stripe_head *sh, int num) | |
190 | { | |
191 | struct page *p; | |
192 | int i; | |
193 | ||
194 | for (i=0; i<num ; i++) { | |
195 | p = sh->dev[i].page; | |
196 | if (!p) | |
197 | continue; | |
198 | sh->dev[i].page = NULL; | |
2d1f3b5d | 199 | put_page(p); |
1da177e4 LT |
200 | } |
201 | } | |
202 | ||
203 | static int grow_buffers(struct stripe_head *sh, int num) | |
204 | { | |
205 | int i; | |
206 | ||
207 | for (i=0; i<num; i++) { | |
208 | struct page *page; | |
209 | ||
210 | if (!(page = alloc_page(GFP_KERNEL))) { | |
211 | return 1; | |
212 | } | |
213 | sh->dev[i].page = page; | |
214 | } | |
215 | return 0; | |
216 | } | |
217 | ||
218 | static void raid5_build_block (struct stripe_head *sh, int i); | |
219 | ||
7ecaa1e6 | 220 | static void init_stripe(struct stripe_head *sh, sector_t sector, int pd_idx, int disks) |
1da177e4 LT |
221 | { |
222 | raid5_conf_t *conf = sh->raid_conf; | |
7ecaa1e6 | 223 | int i; |
1da177e4 | 224 | |
78bafebd ES |
225 | BUG_ON(atomic_read(&sh->count) != 0); |
226 | BUG_ON(test_bit(STRIPE_HANDLE, &sh->state)); | |
1da177e4 LT |
227 | |
228 | CHECK_DEVLOCK(); | |
229 | PRINTK("init_stripe called, stripe %llu\n", | |
230 | (unsigned long long)sh->sector); | |
231 | ||
232 | remove_hash(sh); | |
16a53ecc | 233 | |
1da177e4 LT |
234 | sh->sector = sector; |
235 | sh->pd_idx = pd_idx; | |
236 | sh->state = 0; | |
237 | ||
7ecaa1e6 N |
238 | sh->disks = disks; |
239 | ||
240 | for (i = sh->disks; i--; ) { | |
1da177e4 LT |
241 | struct r5dev *dev = &sh->dev[i]; |
242 | ||
243 | if (dev->toread || dev->towrite || dev->written || | |
244 | test_bit(R5_LOCKED, &dev->flags)) { | |
245 | printk("sector=%llx i=%d %p %p %p %d\n", | |
246 | (unsigned long long)sh->sector, i, dev->toread, | |
247 | dev->towrite, dev->written, | |
248 | test_bit(R5_LOCKED, &dev->flags)); | |
249 | BUG(); | |
250 | } | |
251 | dev->flags = 0; | |
252 | raid5_build_block(sh, i); | |
253 | } | |
254 | insert_hash(conf, sh); | |
255 | } | |
256 | ||
7ecaa1e6 | 257 | static struct stripe_head *__find_stripe(raid5_conf_t *conf, sector_t sector, int disks) |
1da177e4 LT |
258 | { |
259 | struct stripe_head *sh; | |
fccddba0 | 260 | struct hlist_node *hn; |
1da177e4 LT |
261 | |
262 | CHECK_DEVLOCK(); | |
263 | PRINTK("__find_stripe, sector %llu\n", (unsigned long long)sector); | |
fccddba0 | 264 | hlist_for_each_entry(sh, hn, stripe_hash(conf, sector), hash) |
7ecaa1e6 | 265 | if (sh->sector == sector && sh->disks == disks) |
1da177e4 LT |
266 | return sh; |
267 | PRINTK("__stripe %llu not in cache\n", (unsigned long long)sector); | |
268 | return NULL; | |
269 | } | |
270 | ||
271 | static void unplug_slaves(mddev_t *mddev); | |
272 | static void raid5_unplug_device(request_queue_t *q); | |
273 | ||
7ecaa1e6 N |
274 | static struct stripe_head *get_active_stripe(raid5_conf_t *conf, sector_t sector, int disks, |
275 | int pd_idx, int noblock) | |
1da177e4 LT |
276 | { |
277 | struct stripe_head *sh; | |
278 | ||
279 | PRINTK("get_stripe, sector %llu\n", (unsigned long long)sector); | |
280 | ||
281 | spin_lock_irq(&conf->device_lock); | |
282 | ||
283 | do { | |
72626685 N |
284 | wait_event_lock_irq(conf->wait_for_stripe, |
285 | conf->quiesce == 0, | |
286 | conf->device_lock, /* nothing */); | |
7ecaa1e6 | 287 | sh = __find_stripe(conf, sector, disks); |
1da177e4 LT |
288 | if (!sh) { |
289 | if (!conf->inactive_blocked) | |
290 | sh = get_free_stripe(conf); | |
291 | if (noblock && sh == NULL) | |
292 | break; | |
293 | if (!sh) { | |
294 | conf->inactive_blocked = 1; | |
295 | wait_event_lock_irq(conf->wait_for_stripe, | |
296 | !list_empty(&conf->inactive_list) && | |
5036805b N |
297 | (atomic_read(&conf->active_stripes) |
298 | < (conf->max_nr_stripes *3/4) | |
1da177e4 LT |
299 | || !conf->inactive_blocked), |
300 | conf->device_lock, | |
f4370781 | 301 | raid5_unplug_device(conf->mddev->queue) |
1da177e4 LT |
302 | ); |
303 | conf->inactive_blocked = 0; | |
304 | } else | |
7ecaa1e6 | 305 | init_stripe(sh, sector, pd_idx, disks); |
1da177e4 LT |
306 | } else { |
307 | if (atomic_read(&sh->count)) { | |
78bafebd | 308 | BUG_ON(!list_empty(&sh->lru)); |
1da177e4 LT |
309 | } else { |
310 | if (!test_bit(STRIPE_HANDLE, &sh->state)) | |
311 | atomic_inc(&conf->active_stripes); | |
ff4e8d9a N |
312 | if (list_empty(&sh->lru) && |
313 | !test_bit(STRIPE_EXPANDING, &sh->state)) | |
16a53ecc N |
314 | BUG(); |
315 | list_del_init(&sh->lru); | |
1da177e4 LT |
316 | } |
317 | } | |
318 | } while (sh == NULL); | |
319 | ||
320 | if (sh) | |
321 | atomic_inc(&sh->count); | |
322 | ||
323 | spin_unlock_irq(&conf->device_lock); | |
324 | return sh; | |
325 | } | |
326 | ||
3f294f4f | 327 | static int grow_one_stripe(raid5_conf_t *conf) |
1da177e4 LT |
328 | { |
329 | struct stripe_head *sh; | |
3f294f4f N |
330 | sh = kmem_cache_alloc(conf->slab_cache, GFP_KERNEL); |
331 | if (!sh) | |
332 | return 0; | |
333 | memset(sh, 0, sizeof(*sh) + (conf->raid_disks-1)*sizeof(struct r5dev)); | |
334 | sh->raid_conf = conf; | |
335 | spin_lock_init(&sh->lock); | |
336 | ||
337 | if (grow_buffers(sh, conf->raid_disks)) { | |
338 | shrink_buffers(sh, conf->raid_disks); | |
339 | kmem_cache_free(conf->slab_cache, sh); | |
340 | return 0; | |
341 | } | |
7ecaa1e6 | 342 | sh->disks = conf->raid_disks; |
3f294f4f N |
343 | /* we just created an active stripe so... */ |
344 | atomic_set(&sh->count, 1); | |
345 | atomic_inc(&conf->active_stripes); | |
346 | INIT_LIST_HEAD(&sh->lru); | |
347 | release_stripe(sh); | |
348 | return 1; | |
349 | } | |
350 | ||
351 | static int grow_stripes(raid5_conf_t *conf, int num) | |
352 | { | |
e18b890b | 353 | struct kmem_cache *sc; |
1da177e4 LT |
354 | int devs = conf->raid_disks; |
355 | ||
ad01c9e3 N |
356 | sprintf(conf->cache_name[0], "raid5/%s", mdname(conf->mddev)); |
357 | sprintf(conf->cache_name[1], "raid5/%s-alt", mdname(conf->mddev)); | |
358 | conf->active_name = 0; | |
359 | sc = kmem_cache_create(conf->cache_name[conf->active_name], | |
1da177e4 LT |
360 | sizeof(struct stripe_head)+(devs-1)*sizeof(struct r5dev), |
361 | 0, 0, NULL, NULL); | |
362 | if (!sc) | |
363 | return 1; | |
364 | conf->slab_cache = sc; | |
ad01c9e3 | 365 | conf->pool_size = devs; |
16a53ecc | 366 | while (num--) |
3f294f4f | 367 | if (!grow_one_stripe(conf)) |
1da177e4 | 368 | return 1; |
1da177e4 LT |
369 | return 0; |
370 | } | |
29269553 N |
371 | |
372 | #ifdef CONFIG_MD_RAID5_RESHAPE | |
ad01c9e3 N |
373 | static int resize_stripes(raid5_conf_t *conf, int newsize) |
374 | { | |
375 | /* Make all the stripes able to hold 'newsize' devices. | |
376 | * New slots in each stripe get 'page' set to a new page. | |
377 | * | |
378 | * This happens in stages: | |
379 | * 1/ create a new kmem_cache and allocate the required number of | |
380 | * stripe_heads. | |
381 | * 2/ gather all the old stripe_heads and tranfer the pages across | |
382 | * to the new stripe_heads. This will have the side effect of | |
383 | * freezing the array as once all stripe_heads have been collected, | |
384 | * no IO will be possible. Old stripe heads are freed once their | |
385 | * pages have been transferred over, and the old kmem_cache is | |
386 | * freed when all stripes are done. | |
387 | * 3/ reallocate conf->disks to be suitable bigger. If this fails, | |
388 | * we simple return a failre status - no need to clean anything up. | |
389 | * 4/ allocate new pages for the new slots in the new stripe_heads. | |
390 | * If this fails, we don't bother trying the shrink the | |
391 | * stripe_heads down again, we just leave them as they are. | |
392 | * As each stripe_head is processed the new one is released into | |
393 | * active service. | |
394 | * | |
395 | * Once step2 is started, we cannot afford to wait for a write, | |
396 | * so we use GFP_NOIO allocations. | |
397 | */ | |
398 | struct stripe_head *osh, *nsh; | |
399 | LIST_HEAD(newstripes); | |
400 | struct disk_info *ndisks; | |
401 | int err = 0; | |
e18b890b | 402 | struct kmem_cache *sc; |
ad01c9e3 N |
403 | int i; |
404 | ||
405 | if (newsize <= conf->pool_size) | |
406 | return 0; /* never bother to shrink */ | |
407 | ||
2a2275d6 N |
408 | md_allow_write(conf->mddev); |
409 | ||
ad01c9e3 N |
410 | /* Step 1 */ |
411 | sc = kmem_cache_create(conf->cache_name[1-conf->active_name], | |
412 | sizeof(struct stripe_head)+(newsize-1)*sizeof(struct r5dev), | |
413 | 0, 0, NULL, NULL); | |
414 | if (!sc) | |
415 | return -ENOMEM; | |
416 | ||
417 | for (i = conf->max_nr_stripes; i; i--) { | |
418 | nsh = kmem_cache_alloc(sc, GFP_KERNEL); | |
419 | if (!nsh) | |
420 | break; | |
421 | ||
422 | memset(nsh, 0, sizeof(*nsh) + (newsize-1)*sizeof(struct r5dev)); | |
423 | ||
424 | nsh->raid_conf = conf; | |
425 | spin_lock_init(&nsh->lock); | |
426 | ||
427 | list_add(&nsh->lru, &newstripes); | |
428 | } | |
429 | if (i) { | |
430 | /* didn't get enough, give up */ | |
431 | while (!list_empty(&newstripes)) { | |
432 | nsh = list_entry(newstripes.next, struct stripe_head, lru); | |
433 | list_del(&nsh->lru); | |
434 | kmem_cache_free(sc, nsh); | |
435 | } | |
436 | kmem_cache_destroy(sc); | |
437 | return -ENOMEM; | |
438 | } | |
439 | /* Step 2 - Must use GFP_NOIO now. | |
440 | * OK, we have enough stripes, start collecting inactive | |
441 | * stripes and copying them over | |
442 | */ | |
443 | list_for_each_entry(nsh, &newstripes, lru) { | |
444 | spin_lock_irq(&conf->device_lock); | |
445 | wait_event_lock_irq(conf->wait_for_stripe, | |
446 | !list_empty(&conf->inactive_list), | |
447 | conf->device_lock, | |
b3b46be3 | 448 | unplug_slaves(conf->mddev) |
ad01c9e3 N |
449 | ); |
450 | osh = get_free_stripe(conf); | |
451 | spin_unlock_irq(&conf->device_lock); | |
452 | atomic_set(&nsh->count, 1); | |
453 | for(i=0; i<conf->pool_size; i++) | |
454 | nsh->dev[i].page = osh->dev[i].page; | |
455 | for( ; i<newsize; i++) | |
456 | nsh->dev[i].page = NULL; | |
457 | kmem_cache_free(conf->slab_cache, osh); | |
458 | } | |
459 | kmem_cache_destroy(conf->slab_cache); | |
460 | ||
461 | /* Step 3. | |
462 | * At this point, we are holding all the stripes so the array | |
463 | * is completely stalled, so now is a good time to resize | |
464 | * conf->disks. | |
465 | */ | |
466 | ndisks = kzalloc(newsize * sizeof(struct disk_info), GFP_NOIO); | |
467 | if (ndisks) { | |
468 | for (i=0; i<conf->raid_disks; i++) | |
469 | ndisks[i] = conf->disks[i]; | |
470 | kfree(conf->disks); | |
471 | conf->disks = ndisks; | |
472 | } else | |
473 | err = -ENOMEM; | |
474 | ||
475 | /* Step 4, return new stripes to service */ | |
476 | while(!list_empty(&newstripes)) { | |
477 | nsh = list_entry(newstripes.next, struct stripe_head, lru); | |
478 | list_del_init(&nsh->lru); | |
479 | for (i=conf->raid_disks; i < newsize; i++) | |
480 | if (nsh->dev[i].page == NULL) { | |
481 | struct page *p = alloc_page(GFP_NOIO); | |
482 | nsh->dev[i].page = p; | |
483 | if (!p) | |
484 | err = -ENOMEM; | |
485 | } | |
486 | release_stripe(nsh); | |
487 | } | |
488 | /* critical section pass, GFP_NOIO no longer needed */ | |
489 | ||
490 | conf->slab_cache = sc; | |
491 | conf->active_name = 1-conf->active_name; | |
492 | conf->pool_size = newsize; | |
493 | return err; | |
494 | } | |
29269553 | 495 | #endif |
1da177e4 | 496 | |
3f294f4f | 497 | static int drop_one_stripe(raid5_conf_t *conf) |
1da177e4 LT |
498 | { |
499 | struct stripe_head *sh; | |
500 | ||
3f294f4f N |
501 | spin_lock_irq(&conf->device_lock); |
502 | sh = get_free_stripe(conf); | |
503 | spin_unlock_irq(&conf->device_lock); | |
504 | if (!sh) | |
505 | return 0; | |
78bafebd | 506 | BUG_ON(atomic_read(&sh->count)); |
ad01c9e3 | 507 | shrink_buffers(sh, conf->pool_size); |
3f294f4f N |
508 | kmem_cache_free(conf->slab_cache, sh); |
509 | atomic_dec(&conf->active_stripes); | |
510 | return 1; | |
511 | } | |
512 | ||
513 | static void shrink_stripes(raid5_conf_t *conf) | |
514 | { | |
515 | while (drop_one_stripe(conf)) | |
516 | ; | |
517 | ||
29fc7e3e N |
518 | if (conf->slab_cache) |
519 | kmem_cache_destroy(conf->slab_cache); | |
1da177e4 LT |
520 | conf->slab_cache = NULL; |
521 | } | |
522 | ||
4e5314b5 | 523 | static int raid5_end_read_request(struct bio * bi, unsigned int bytes_done, |
1da177e4 LT |
524 | int error) |
525 | { | |
526 | struct stripe_head *sh = bi->bi_private; | |
527 | raid5_conf_t *conf = sh->raid_conf; | |
7ecaa1e6 | 528 | int disks = sh->disks, i; |
1da177e4 | 529 | int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags); |
d6950432 N |
530 | char b[BDEVNAME_SIZE]; |
531 | mdk_rdev_t *rdev; | |
1da177e4 LT |
532 | |
533 | if (bi->bi_size) | |
534 | return 1; | |
535 | ||
536 | for (i=0 ; i<disks; i++) | |
537 | if (bi == &sh->dev[i].req) | |
538 | break; | |
539 | ||
540 | PRINTK("end_read_request %llu/%d, count: %d, uptodate %d.\n", | |
541 | (unsigned long long)sh->sector, i, atomic_read(&sh->count), | |
542 | uptodate); | |
543 | if (i == disks) { | |
544 | BUG(); | |
545 | return 0; | |
546 | } | |
547 | ||
548 | if (uptodate) { | |
1da177e4 | 549 | set_bit(R5_UPTODATE, &sh->dev[i].flags); |
4e5314b5 | 550 | if (test_bit(R5_ReadError, &sh->dev[i].flags)) { |
d6950432 N |
551 | rdev = conf->disks[i].rdev; |
552 | printk(KERN_INFO "raid5:%s: read error corrected (%lu sectors at %llu on %s)\n", | |
553 | mdname(conf->mddev), STRIPE_SECTORS, | |
554 | (unsigned long long)sh->sector + rdev->data_offset, | |
555 | bdevname(rdev->bdev, b)); | |
4e5314b5 N |
556 | clear_bit(R5_ReadError, &sh->dev[i].flags); |
557 | clear_bit(R5_ReWrite, &sh->dev[i].flags); | |
558 | } | |
ba22dcbf N |
559 | if (atomic_read(&conf->disks[i].rdev->read_errors)) |
560 | atomic_set(&conf->disks[i].rdev->read_errors, 0); | |
1da177e4 | 561 | } else { |
d6950432 | 562 | const char *bdn = bdevname(conf->disks[i].rdev->bdev, b); |
ba22dcbf | 563 | int retry = 0; |
d6950432 N |
564 | rdev = conf->disks[i].rdev; |
565 | ||
1da177e4 | 566 | clear_bit(R5_UPTODATE, &sh->dev[i].flags); |
d6950432 | 567 | atomic_inc(&rdev->read_errors); |
ba22dcbf | 568 | if (conf->mddev->degraded) |
d6950432 N |
569 | printk(KERN_WARNING "raid5:%s: read error not correctable (sector %llu on %s).\n", |
570 | mdname(conf->mddev), | |
571 | (unsigned long long)sh->sector + rdev->data_offset, | |
572 | bdn); | |
ba22dcbf | 573 | else if (test_bit(R5_ReWrite, &sh->dev[i].flags)) |
4e5314b5 | 574 | /* Oh, no!!! */ |
d6950432 N |
575 | printk(KERN_WARNING "raid5:%s: read error NOT corrected!! (sector %llu on %s).\n", |
576 | mdname(conf->mddev), | |
577 | (unsigned long long)sh->sector + rdev->data_offset, | |
578 | bdn); | |
579 | else if (atomic_read(&rdev->read_errors) | |
ba22dcbf | 580 | > conf->max_nr_stripes) |
14f8d26b | 581 | printk(KERN_WARNING |
d6950432 N |
582 | "raid5:%s: Too many read errors, failing device %s.\n", |
583 | mdname(conf->mddev), bdn); | |
ba22dcbf N |
584 | else |
585 | retry = 1; | |
586 | if (retry) | |
587 | set_bit(R5_ReadError, &sh->dev[i].flags); | |
588 | else { | |
4e5314b5 N |
589 | clear_bit(R5_ReadError, &sh->dev[i].flags); |
590 | clear_bit(R5_ReWrite, &sh->dev[i].flags); | |
d6950432 | 591 | md_error(conf->mddev, rdev); |
ba22dcbf | 592 | } |
1da177e4 LT |
593 | } |
594 | rdev_dec_pending(conf->disks[i].rdev, conf->mddev); | |
1da177e4 LT |
595 | clear_bit(R5_LOCKED, &sh->dev[i].flags); |
596 | set_bit(STRIPE_HANDLE, &sh->state); | |
597 | release_stripe(sh); | |
598 | return 0; | |
599 | } | |
600 | ||
601 | static int raid5_end_write_request (struct bio *bi, unsigned int bytes_done, | |
602 | int error) | |
603 | { | |
604 | struct stripe_head *sh = bi->bi_private; | |
605 | raid5_conf_t *conf = sh->raid_conf; | |
7ecaa1e6 | 606 | int disks = sh->disks, i; |
1da177e4 LT |
607 | int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags); |
608 | ||
609 | if (bi->bi_size) | |
610 | return 1; | |
611 | ||
612 | for (i=0 ; i<disks; i++) | |
613 | if (bi == &sh->dev[i].req) | |
614 | break; | |
615 | ||
616 | PRINTK("end_write_request %llu/%d, count %d, uptodate: %d.\n", | |
617 | (unsigned long long)sh->sector, i, atomic_read(&sh->count), | |
618 | uptodate); | |
619 | if (i == disks) { | |
620 | BUG(); | |
621 | return 0; | |
622 | } | |
623 | ||
1da177e4 LT |
624 | if (!uptodate) |
625 | md_error(conf->mddev, conf->disks[i].rdev); | |
626 | ||
627 | rdev_dec_pending(conf->disks[i].rdev, conf->mddev); | |
628 | ||
629 | clear_bit(R5_LOCKED, &sh->dev[i].flags); | |
630 | set_bit(STRIPE_HANDLE, &sh->state); | |
c04be0aa | 631 | release_stripe(sh); |
1da177e4 LT |
632 | return 0; |
633 | } | |
634 | ||
635 | ||
636 | static sector_t compute_blocknr(struct stripe_head *sh, int i); | |
637 | ||
638 | static void raid5_build_block (struct stripe_head *sh, int i) | |
639 | { | |
640 | struct r5dev *dev = &sh->dev[i]; | |
641 | ||
642 | bio_init(&dev->req); | |
643 | dev->req.bi_io_vec = &dev->vec; | |
644 | dev->req.bi_vcnt++; | |
645 | dev->req.bi_max_vecs++; | |
646 | dev->vec.bv_page = dev->page; | |
647 | dev->vec.bv_len = STRIPE_SIZE; | |
648 | dev->vec.bv_offset = 0; | |
649 | ||
650 | dev->req.bi_sector = sh->sector; | |
651 | dev->req.bi_private = sh; | |
652 | ||
653 | dev->flags = 0; | |
16a53ecc | 654 | dev->sector = compute_blocknr(sh, i); |
1da177e4 LT |
655 | } |
656 | ||
657 | static void error(mddev_t *mddev, mdk_rdev_t *rdev) | |
658 | { | |
659 | char b[BDEVNAME_SIZE]; | |
660 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; | |
661 | PRINTK("raid5: error called\n"); | |
662 | ||
b2d444d7 | 663 | if (!test_bit(Faulty, &rdev->flags)) { |
850b2b42 | 664 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
c04be0aa N |
665 | if (test_and_clear_bit(In_sync, &rdev->flags)) { |
666 | unsigned long flags; | |
667 | spin_lock_irqsave(&conf->device_lock, flags); | |
1da177e4 | 668 | mddev->degraded++; |
c04be0aa | 669 | spin_unlock_irqrestore(&conf->device_lock, flags); |
1da177e4 LT |
670 | /* |
671 | * if recovery was running, make sure it aborts. | |
672 | */ | |
673 | set_bit(MD_RECOVERY_ERR, &mddev->recovery); | |
674 | } | |
b2d444d7 | 675 | set_bit(Faulty, &rdev->flags); |
1da177e4 LT |
676 | printk (KERN_ALERT |
677 | "raid5: Disk failure on %s, disabling device." | |
678 | " Operation continuing on %d devices\n", | |
02c2de8c | 679 | bdevname(rdev->bdev,b), conf->raid_disks - mddev->degraded); |
1da177e4 | 680 | } |
16a53ecc | 681 | } |
1da177e4 LT |
682 | |
683 | /* | |
684 | * Input: a 'big' sector number, | |
685 | * Output: index of the data and parity disk, and the sector # in them. | |
686 | */ | |
687 | static sector_t raid5_compute_sector(sector_t r_sector, unsigned int raid_disks, | |
688 | unsigned int data_disks, unsigned int * dd_idx, | |
689 | unsigned int * pd_idx, raid5_conf_t *conf) | |
690 | { | |
691 | long stripe; | |
692 | unsigned long chunk_number; | |
693 | unsigned int chunk_offset; | |
694 | sector_t new_sector; | |
695 | int sectors_per_chunk = conf->chunk_size >> 9; | |
696 | ||
697 | /* First compute the information on this sector */ | |
698 | ||
699 | /* | |
700 | * Compute the chunk number and the sector offset inside the chunk | |
701 | */ | |
702 | chunk_offset = sector_div(r_sector, sectors_per_chunk); | |
703 | chunk_number = r_sector; | |
704 | BUG_ON(r_sector != chunk_number); | |
705 | ||
706 | /* | |
707 | * Compute the stripe number | |
708 | */ | |
709 | stripe = chunk_number / data_disks; | |
710 | ||
711 | /* | |
712 | * Compute the data disk and parity disk indexes inside the stripe | |
713 | */ | |
714 | *dd_idx = chunk_number % data_disks; | |
715 | ||
716 | /* | |
717 | * Select the parity disk based on the user selected algorithm. | |
718 | */ | |
16a53ecc N |
719 | switch(conf->level) { |
720 | case 4: | |
1da177e4 | 721 | *pd_idx = data_disks; |
16a53ecc N |
722 | break; |
723 | case 5: | |
724 | switch (conf->algorithm) { | |
1da177e4 LT |
725 | case ALGORITHM_LEFT_ASYMMETRIC: |
726 | *pd_idx = data_disks - stripe % raid_disks; | |
727 | if (*dd_idx >= *pd_idx) | |
728 | (*dd_idx)++; | |
729 | break; | |
730 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
731 | *pd_idx = stripe % raid_disks; | |
732 | if (*dd_idx >= *pd_idx) | |
733 | (*dd_idx)++; | |
734 | break; | |
735 | case ALGORITHM_LEFT_SYMMETRIC: | |
736 | *pd_idx = data_disks - stripe % raid_disks; | |
737 | *dd_idx = (*pd_idx + 1 + *dd_idx) % raid_disks; | |
738 | break; | |
739 | case ALGORITHM_RIGHT_SYMMETRIC: | |
740 | *pd_idx = stripe % raid_disks; | |
741 | *dd_idx = (*pd_idx + 1 + *dd_idx) % raid_disks; | |
742 | break; | |
743 | default: | |
14f8d26b | 744 | printk(KERN_ERR "raid5: unsupported algorithm %d\n", |
1da177e4 | 745 | conf->algorithm); |
16a53ecc N |
746 | } |
747 | break; | |
748 | case 6: | |
749 | ||
750 | /**** FIX THIS ****/ | |
751 | switch (conf->algorithm) { | |
752 | case ALGORITHM_LEFT_ASYMMETRIC: | |
753 | *pd_idx = raid_disks - 1 - (stripe % raid_disks); | |
754 | if (*pd_idx == raid_disks-1) | |
755 | (*dd_idx)++; /* Q D D D P */ | |
756 | else if (*dd_idx >= *pd_idx) | |
757 | (*dd_idx) += 2; /* D D P Q D */ | |
758 | break; | |
759 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
760 | *pd_idx = stripe % raid_disks; | |
761 | if (*pd_idx == raid_disks-1) | |
762 | (*dd_idx)++; /* Q D D D P */ | |
763 | else if (*dd_idx >= *pd_idx) | |
764 | (*dd_idx) += 2; /* D D P Q D */ | |
765 | break; | |
766 | case ALGORITHM_LEFT_SYMMETRIC: | |
767 | *pd_idx = raid_disks - 1 - (stripe % raid_disks); | |
768 | *dd_idx = (*pd_idx + 2 + *dd_idx) % raid_disks; | |
769 | break; | |
770 | case ALGORITHM_RIGHT_SYMMETRIC: | |
771 | *pd_idx = stripe % raid_disks; | |
772 | *dd_idx = (*pd_idx + 2 + *dd_idx) % raid_disks; | |
773 | break; | |
774 | default: | |
775 | printk (KERN_CRIT "raid6: unsupported algorithm %d\n", | |
776 | conf->algorithm); | |
777 | } | |
778 | break; | |
1da177e4 LT |
779 | } |
780 | ||
781 | /* | |
782 | * Finally, compute the new sector number | |
783 | */ | |
784 | new_sector = (sector_t)stripe * sectors_per_chunk + chunk_offset; | |
785 | return new_sector; | |
786 | } | |
787 | ||
788 | ||
789 | static sector_t compute_blocknr(struct stripe_head *sh, int i) | |
790 | { | |
791 | raid5_conf_t *conf = sh->raid_conf; | |
b875e531 N |
792 | int raid_disks = sh->disks; |
793 | int data_disks = raid_disks - conf->max_degraded; | |
1da177e4 LT |
794 | sector_t new_sector = sh->sector, check; |
795 | int sectors_per_chunk = conf->chunk_size >> 9; | |
796 | sector_t stripe; | |
797 | int chunk_offset; | |
798 | int chunk_number, dummy1, dummy2, dd_idx = i; | |
799 | sector_t r_sector; | |
800 | ||
16a53ecc | 801 | |
1da177e4 LT |
802 | chunk_offset = sector_div(new_sector, sectors_per_chunk); |
803 | stripe = new_sector; | |
804 | BUG_ON(new_sector != stripe); | |
805 | ||
16a53ecc N |
806 | if (i == sh->pd_idx) |
807 | return 0; | |
808 | switch(conf->level) { | |
809 | case 4: break; | |
810 | case 5: | |
811 | switch (conf->algorithm) { | |
1da177e4 LT |
812 | case ALGORITHM_LEFT_ASYMMETRIC: |
813 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
814 | if (i > sh->pd_idx) | |
815 | i--; | |
816 | break; | |
817 | case ALGORITHM_LEFT_SYMMETRIC: | |
818 | case ALGORITHM_RIGHT_SYMMETRIC: | |
819 | if (i < sh->pd_idx) | |
820 | i += raid_disks; | |
821 | i -= (sh->pd_idx + 1); | |
822 | break; | |
823 | default: | |
14f8d26b | 824 | printk(KERN_ERR "raid5: unsupported algorithm %d\n", |
16a53ecc N |
825 | conf->algorithm); |
826 | } | |
827 | break; | |
828 | case 6: | |
16a53ecc N |
829 | if (i == raid6_next_disk(sh->pd_idx, raid_disks)) |
830 | return 0; /* It is the Q disk */ | |
831 | switch (conf->algorithm) { | |
832 | case ALGORITHM_LEFT_ASYMMETRIC: | |
833 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
834 | if (sh->pd_idx == raid_disks-1) | |
835 | i--; /* Q D D D P */ | |
836 | else if (i > sh->pd_idx) | |
837 | i -= 2; /* D D P Q D */ | |
838 | break; | |
839 | case ALGORITHM_LEFT_SYMMETRIC: | |
840 | case ALGORITHM_RIGHT_SYMMETRIC: | |
841 | if (sh->pd_idx == raid_disks-1) | |
842 | i--; /* Q D D D P */ | |
843 | else { | |
844 | /* D D P Q D */ | |
845 | if (i < sh->pd_idx) | |
846 | i += raid_disks; | |
847 | i -= (sh->pd_idx + 2); | |
848 | } | |
849 | break; | |
850 | default: | |
851 | printk (KERN_CRIT "raid6: unsupported algorithm %d\n", | |
1da177e4 | 852 | conf->algorithm); |
16a53ecc N |
853 | } |
854 | break; | |
1da177e4 LT |
855 | } |
856 | ||
857 | chunk_number = stripe * data_disks + i; | |
858 | r_sector = (sector_t)chunk_number * sectors_per_chunk + chunk_offset; | |
859 | ||
860 | check = raid5_compute_sector (r_sector, raid_disks, data_disks, &dummy1, &dummy2, conf); | |
861 | if (check != sh->sector || dummy1 != dd_idx || dummy2 != sh->pd_idx) { | |
14f8d26b | 862 | printk(KERN_ERR "compute_blocknr: map not correct\n"); |
1da177e4 LT |
863 | return 0; |
864 | } | |
865 | return r_sector; | |
866 | } | |
867 | ||
868 | ||
869 | ||
870 | /* | |
16a53ecc N |
871 | * Copy data between a page in the stripe cache, and one or more bion |
872 | * The page could align with the middle of the bio, or there could be | |
873 | * several bion, each with several bio_vecs, which cover part of the page | |
874 | * Multiple bion are linked together on bi_next. There may be extras | |
875 | * at the end of this list. We ignore them. | |
1da177e4 LT |
876 | */ |
877 | static void copy_data(int frombio, struct bio *bio, | |
878 | struct page *page, | |
879 | sector_t sector) | |
880 | { | |
881 | char *pa = page_address(page); | |
882 | struct bio_vec *bvl; | |
883 | int i; | |
884 | int page_offset; | |
885 | ||
886 | if (bio->bi_sector >= sector) | |
887 | page_offset = (signed)(bio->bi_sector - sector) * 512; | |
888 | else | |
889 | page_offset = (signed)(sector - bio->bi_sector) * -512; | |
890 | bio_for_each_segment(bvl, bio, i) { | |
891 | int len = bio_iovec_idx(bio,i)->bv_len; | |
892 | int clen; | |
893 | int b_offset = 0; | |
894 | ||
895 | if (page_offset < 0) { | |
896 | b_offset = -page_offset; | |
897 | page_offset += b_offset; | |
898 | len -= b_offset; | |
899 | } | |
900 | ||
901 | if (len > 0 && page_offset + len > STRIPE_SIZE) | |
902 | clen = STRIPE_SIZE - page_offset; | |
903 | else clen = len; | |
16a53ecc | 904 | |
1da177e4 LT |
905 | if (clen > 0) { |
906 | char *ba = __bio_kmap_atomic(bio, i, KM_USER0); | |
907 | if (frombio) | |
908 | memcpy(pa+page_offset, ba+b_offset, clen); | |
909 | else | |
910 | memcpy(ba+b_offset, pa+page_offset, clen); | |
911 | __bio_kunmap_atomic(ba, KM_USER0); | |
912 | } | |
913 | if (clen < len) /* hit end of page */ | |
914 | break; | |
915 | page_offset += len; | |
916 | } | |
917 | } | |
918 | ||
919 | #define check_xor() do { \ | |
920 | if (count == MAX_XOR_BLOCKS) { \ | |
921 | xor_block(count, STRIPE_SIZE, ptr); \ | |
922 | count = 1; \ | |
923 | } \ | |
924 | } while(0) | |
925 | ||
926 | ||
927 | static void compute_block(struct stripe_head *sh, int dd_idx) | |
928 | { | |
7ecaa1e6 | 929 | int i, count, disks = sh->disks; |
1da177e4 LT |
930 | void *ptr[MAX_XOR_BLOCKS], *p; |
931 | ||
932 | PRINTK("compute_block, stripe %llu, idx %d\n", | |
933 | (unsigned long long)sh->sector, dd_idx); | |
934 | ||
935 | ptr[0] = page_address(sh->dev[dd_idx].page); | |
936 | memset(ptr[0], 0, STRIPE_SIZE); | |
937 | count = 1; | |
938 | for (i = disks ; i--; ) { | |
939 | if (i == dd_idx) | |
940 | continue; | |
941 | p = page_address(sh->dev[i].page); | |
942 | if (test_bit(R5_UPTODATE, &sh->dev[i].flags)) | |
943 | ptr[count++] = p; | |
944 | else | |
14f8d26b | 945 | printk(KERN_ERR "compute_block() %d, stripe %llu, %d" |
1da177e4 LT |
946 | " not present\n", dd_idx, |
947 | (unsigned long long)sh->sector, i); | |
948 | ||
949 | check_xor(); | |
950 | } | |
951 | if (count != 1) | |
952 | xor_block(count, STRIPE_SIZE, ptr); | |
953 | set_bit(R5_UPTODATE, &sh->dev[dd_idx].flags); | |
954 | } | |
955 | ||
16a53ecc | 956 | static void compute_parity5(struct stripe_head *sh, int method) |
1da177e4 LT |
957 | { |
958 | raid5_conf_t *conf = sh->raid_conf; | |
7ecaa1e6 | 959 | int i, pd_idx = sh->pd_idx, disks = sh->disks, count; |
1da177e4 LT |
960 | void *ptr[MAX_XOR_BLOCKS]; |
961 | struct bio *chosen; | |
962 | ||
16a53ecc | 963 | PRINTK("compute_parity5, stripe %llu, method %d\n", |
1da177e4 LT |
964 | (unsigned long long)sh->sector, method); |
965 | ||
966 | count = 1; | |
967 | ptr[0] = page_address(sh->dev[pd_idx].page); | |
968 | switch(method) { | |
969 | case READ_MODIFY_WRITE: | |
78bafebd | 970 | BUG_ON(!test_bit(R5_UPTODATE, &sh->dev[pd_idx].flags)); |
1da177e4 LT |
971 | for (i=disks ; i-- ;) { |
972 | if (i==pd_idx) | |
973 | continue; | |
974 | if (sh->dev[i].towrite && | |
975 | test_bit(R5_UPTODATE, &sh->dev[i].flags)) { | |
976 | ptr[count++] = page_address(sh->dev[i].page); | |
977 | chosen = sh->dev[i].towrite; | |
978 | sh->dev[i].towrite = NULL; | |
979 | ||
980 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) | |
981 | wake_up(&conf->wait_for_overlap); | |
982 | ||
78bafebd | 983 | BUG_ON(sh->dev[i].written); |
1da177e4 LT |
984 | sh->dev[i].written = chosen; |
985 | check_xor(); | |
986 | } | |
987 | } | |
988 | break; | |
989 | case RECONSTRUCT_WRITE: | |
990 | memset(ptr[0], 0, STRIPE_SIZE); | |
991 | for (i= disks; i-- ;) | |
992 | if (i!=pd_idx && sh->dev[i].towrite) { | |
993 | chosen = sh->dev[i].towrite; | |
994 | sh->dev[i].towrite = NULL; | |
995 | ||
996 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) | |
997 | wake_up(&conf->wait_for_overlap); | |
998 | ||
78bafebd | 999 | BUG_ON(sh->dev[i].written); |
1da177e4 LT |
1000 | sh->dev[i].written = chosen; |
1001 | } | |
1002 | break; | |
1003 | case CHECK_PARITY: | |
1004 | break; | |
1005 | } | |
1006 | if (count>1) { | |
1007 | xor_block(count, STRIPE_SIZE, ptr); | |
1008 | count = 1; | |
1009 | } | |
1010 | ||
1011 | for (i = disks; i--;) | |
1012 | if (sh->dev[i].written) { | |
1013 | sector_t sector = sh->dev[i].sector; | |
1014 | struct bio *wbi = sh->dev[i].written; | |
1015 | while (wbi && wbi->bi_sector < sector + STRIPE_SECTORS) { | |
1016 | copy_data(1, wbi, sh->dev[i].page, sector); | |
1017 | wbi = r5_next_bio(wbi, sector); | |
1018 | } | |
1019 | ||
1020 | set_bit(R5_LOCKED, &sh->dev[i].flags); | |
1021 | set_bit(R5_UPTODATE, &sh->dev[i].flags); | |
1022 | } | |
1023 | ||
1024 | switch(method) { | |
1025 | case RECONSTRUCT_WRITE: | |
1026 | case CHECK_PARITY: | |
1027 | for (i=disks; i--;) | |
1028 | if (i != pd_idx) { | |
1029 | ptr[count++] = page_address(sh->dev[i].page); | |
1030 | check_xor(); | |
1031 | } | |
1032 | break; | |
1033 | case READ_MODIFY_WRITE: | |
1034 | for (i = disks; i--;) | |
1035 | if (sh->dev[i].written) { | |
1036 | ptr[count++] = page_address(sh->dev[i].page); | |
1037 | check_xor(); | |
1038 | } | |
1039 | } | |
1040 | if (count != 1) | |
1041 | xor_block(count, STRIPE_SIZE, ptr); | |
1042 | ||
1043 | if (method != CHECK_PARITY) { | |
1044 | set_bit(R5_UPTODATE, &sh->dev[pd_idx].flags); | |
1045 | set_bit(R5_LOCKED, &sh->dev[pd_idx].flags); | |
1046 | } else | |
1047 | clear_bit(R5_UPTODATE, &sh->dev[pd_idx].flags); | |
1048 | } | |
1049 | ||
16a53ecc N |
1050 | static void compute_parity6(struct stripe_head *sh, int method) |
1051 | { | |
1052 | raid6_conf_t *conf = sh->raid_conf; | |
1053 | int i, pd_idx = sh->pd_idx, qd_idx, d0_idx, disks = conf->raid_disks, count; | |
1054 | struct bio *chosen; | |
1055 | /**** FIX THIS: This could be very bad if disks is close to 256 ****/ | |
1056 | void *ptrs[disks]; | |
1057 | ||
1058 | qd_idx = raid6_next_disk(pd_idx, disks); | |
1059 | d0_idx = raid6_next_disk(qd_idx, disks); | |
1060 | ||
1061 | PRINTK("compute_parity, stripe %llu, method %d\n", | |
1062 | (unsigned long long)sh->sector, method); | |
1063 | ||
1064 | switch(method) { | |
1065 | case READ_MODIFY_WRITE: | |
1066 | BUG(); /* READ_MODIFY_WRITE N/A for RAID-6 */ | |
1067 | case RECONSTRUCT_WRITE: | |
1068 | for (i= disks; i-- ;) | |
1069 | if ( i != pd_idx && i != qd_idx && sh->dev[i].towrite ) { | |
1070 | chosen = sh->dev[i].towrite; | |
1071 | sh->dev[i].towrite = NULL; | |
1072 | ||
1073 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) | |
1074 | wake_up(&conf->wait_for_overlap); | |
1075 | ||
52e5f9d1 | 1076 | BUG_ON(sh->dev[i].written); |
16a53ecc N |
1077 | sh->dev[i].written = chosen; |
1078 | } | |
1079 | break; | |
1080 | case CHECK_PARITY: | |
1081 | BUG(); /* Not implemented yet */ | |
1082 | } | |
1083 | ||
1084 | for (i = disks; i--;) | |
1085 | if (sh->dev[i].written) { | |
1086 | sector_t sector = sh->dev[i].sector; | |
1087 | struct bio *wbi = sh->dev[i].written; | |
1088 | while (wbi && wbi->bi_sector < sector + STRIPE_SECTORS) { | |
1089 | copy_data(1, wbi, sh->dev[i].page, sector); | |
1090 | wbi = r5_next_bio(wbi, sector); | |
1091 | } | |
1092 | ||
1093 | set_bit(R5_LOCKED, &sh->dev[i].flags); | |
1094 | set_bit(R5_UPTODATE, &sh->dev[i].flags); | |
1095 | } | |
1096 | ||
1097 | // switch(method) { | |
1098 | // case RECONSTRUCT_WRITE: | |
1099 | // case CHECK_PARITY: | |
1100 | // case UPDATE_PARITY: | |
1101 | /* Note that unlike RAID-5, the ordering of the disks matters greatly. */ | |
1102 | /* FIX: Is this ordering of drives even remotely optimal? */ | |
1103 | count = 0; | |
1104 | i = d0_idx; | |
1105 | do { | |
1106 | ptrs[count++] = page_address(sh->dev[i].page); | |
1107 | if (count <= disks-2 && !test_bit(R5_UPTODATE, &sh->dev[i].flags)) | |
1108 | printk("block %d/%d not uptodate on parity calc\n", i,count); | |
1109 | i = raid6_next_disk(i, disks); | |
1110 | } while ( i != d0_idx ); | |
1111 | // break; | |
1112 | // } | |
1113 | ||
1114 | raid6_call.gen_syndrome(disks, STRIPE_SIZE, ptrs); | |
1115 | ||
1116 | switch(method) { | |
1117 | case RECONSTRUCT_WRITE: | |
1118 | set_bit(R5_UPTODATE, &sh->dev[pd_idx].flags); | |
1119 | set_bit(R5_UPTODATE, &sh->dev[qd_idx].flags); | |
1120 | set_bit(R5_LOCKED, &sh->dev[pd_idx].flags); | |
1121 | set_bit(R5_LOCKED, &sh->dev[qd_idx].flags); | |
1122 | break; | |
1123 | case UPDATE_PARITY: | |
1124 | set_bit(R5_UPTODATE, &sh->dev[pd_idx].flags); | |
1125 | set_bit(R5_UPTODATE, &sh->dev[qd_idx].flags); | |
1126 | break; | |
1127 | } | |
1128 | } | |
1129 | ||
1130 | ||
1131 | /* Compute one missing block */ | |
1132 | static void compute_block_1(struct stripe_head *sh, int dd_idx, int nozero) | |
1133 | { | |
1134 | raid6_conf_t *conf = sh->raid_conf; | |
1135 | int i, count, disks = conf->raid_disks; | |
1136 | void *ptr[MAX_XOR_BLOCKS], *p; | |
1137 | int pd_idx = sh->pd_idx; | |
1138 | int qd_idx = raid6_next_disk(pd_idx, disks); | |
1139 | ||
1140 | PRINTK("compute_block_1, stripe %llu, idx %d\n", | |
1141 | (unsigned long long)sh->sector, dd_idx); | |
1142 | ||
1143 | if ( dd_idx == qd_idx ) { | |
1144 | /* We're actually computing the Q drive */ | |
1145 | compute_parity6(sh, UPDATE_PARITY); | |
1146 | } else { | |
1147 | ptr[0] = page_address(sh->dev[dd_idx].page); | |
1148 | if (!nozero) memset(ptr[0], 0, STRIPE_SIZE); | |
1149 | count = 1; | |
1150 | for (i = disks ; i--; ) { | |
1151 | if (i == dd_idx || i == qd_idx) | |
1152 | continue; | |
1153 | p = page_address(sh->dev[i].page); | |
1154 | if (test_bit(R5_UPTODATE, &sh->dev[i].flags)) | |
1155 | ptr[count++] = p; | |
1156 | else | |
1157 | printk("compute_block() %d, stripe %llu, %d" | |
1158 | " not present\n", dd_idx, | |
1159 | (unsigned long long)sh->sector, i); | |
1160 | ||
1161 | check_xor(); | |
1162 | } | |
1163 | if (count != 1) | |
1164 | xor_block(count, STRIPE_SIZE, ptr); | |
1165 | if (!nozero) set_bit(R5_UPTODATE, &sh->dev[dd_idx].flags); | |
1166 | else clear_bit(R5_UPTODATE, &sh->dev[dd_idx].flags); | |
1167 | } | |
1168 | } | |
1169 | ||
1170 | /* Compute two missing blocks */ | |
1171 | static void compute_block_2(struct stripe_head *sh, int dd_idx1, int dd_idx2) | |
1172 | { | |
1173 | raid6_conf_t *conf = sh->raid_conf; | |
1174 | int i, count, disks = conf->raid_disks; | |
1175 | int pd_idx = sh->pd_idx; | |
1176 | int qd_idx = raid6_next_disk(pd_idx, disks); | |
1177 | int d0_idx = raid6_next_disk(qd_idx, disks); | |
1178 | int faila, failb; | |
1179 | ||
1180 | /* faila and failb are disk numbers relative to d0_idx */ | |
1181 | /* pd_idx become disks-2 and qd_idx become disks-1 */ | |
1182 | faila = (dd_idx1 < d0_idx) ? dd_idx1+(disks-d0_idx) : dd_idx1-d0_idx; | |
1183 | failb = (dd_idx2 < d0_idx) ? dd_idx2+(disks-d0_idx) : dd_idx2-d0_idx; | |
1184 | ||
1185 | BUG_ON(faila == failb); | |
1186 | if ( failb < faila ) { int tmp = faila; faila = failb; failb = tmp; } | |
1187 | ||
1188 | PRINTK("compute_block_2, stripe %llu, idx %d,%d (%d,%d)\n", | |
1189 | (unsigned long long)sh->sector, dd_idx1, dd_idx2, faila, failb); | |
1190 | ||
1191 | if ( failb == disks-1 ) { | |
1192 | /* Q disk is one of the missing disks */ | |
1193 | if ( faila == disks-2 ) { | |
1194 | /* Missing P+Q, just recompute */ | |
1195 | compute_parity6(sh, UPDATE_PARITY); | |
1196 | return; | |
1197 | } else { | |
1198 | /* We're missing D+Q; recompute D from P */ | |
1199 | compute_block_1(sh, (dd_idx1 == qd_idx) ? dd_idx2 : dd_idx1, 0); | |
1200 | compute_parity6(sh, UPDATE_PARITY); /* Is this necessary? */ | |
1201 | return; | |
1202 | } | |
1203 | } | |
1204 | ||
1205 | /* We're missing D+P or D+D; build pointer table */ | |
1206 | { | |
1207 | /**** FIX THIS: This could be very bad if disks is close to 256 ****/ | |
1208 | void *ptrs[disks]; | |
1209 | ||
1210 | count = 0; | |
1211 | i = d0_idx; | |
1212 | do { | |
1213 | ptrs[count++] = page_address(sh->dev[i].page); | |
1214 | i = raid6_next_disk(i, disks); | |
1215 | if (i != dd_idx1 && i != dd_idx2 && | |
1216 | !test_bit(R5_UPTODATE, &sh->dev[i].flags)) | |
1217 | printk("compute_2 with missing block %d/%d\n", count, i); | |
1218 | } while ( i != d0_idx ); | |
1219 | ||
1220 | if ( failb == disks-2 ) { | |
1221 | /* We're missing D+P. */ | |
1222 | raid6_datap_recov(disks, STRIPE_SIZE, faila, ptrs); | |
1223 | } else { | |
1224 | /* We're missing D+D. */ | |
1225 | raid6_2data_recov(disks, STRIPE_SIZE, faila, failb, ptrs); | |
1226 | } | |
1227 | ||
1228 | /* Both the above update both missing blocks */ | |
1229 | set_bit(R5_UPTODATE, &sh->dev[dd_idx1].flags); | |
1230 | set_bit(R5_UPTODATE, &sh->dev[dd_idx2].flags); | |
1231 | } | |
1232 | } | |
1233 | ||
1234 | ||
1235 | ||
1da177e4 LT |
1236 | /* |
1237 | * Each stripe/dev can have one or more bion attached. | |
16a53ecc | 1238 | * toread/towrite point to the first in a chain. |
1da177e4 LT |
1239 | * The bi_next chain must be in order. |
1240 | */ | |
1241 | static int add_stripe_bio(struct stripe_head *sh, struct bio *bi, int dd_idx, int forwrite) | |
1242 | { | |
1243 | struct bio **bip; | |
1244 | raid5_conf_t *conf = sh->raid_conf; | |
72626685 | 1245 | int firstwrite=0; |
1da177e4 LT |
1246 | |
1247 | PRINTK("adding bh b#%llu to stripe s#%llu\n", | |
1248 | (unsigned long long)bi->bi_sector, | |
1249 | (unsigned long long)sh->sector); | |
1250 | ||
1251 | ||
1252 | spin_lock(&sh->lock); | |
1253 | spin_lock_irq(&conf->device_lock); | |
72626685 | 1254 | if (forwrite) { |
1da177e4 | 1255 | bip = &sh->dev[dd_idx].towrite; |
72626685 N |
1256 | if (*bip == NULL && sh->dev[dd_idx].written == NULL) |
1257 | firstwrite = 1; | |
1258 | } else | |
1da177e4 LT |
1259 | bip = &sh->dev[dd_idx].toread; |
1260 | while (*bip && (*bip)->bi_sector < bi->bi_sector) { | |
1261 | if ((*bip)->bi_sector + ((*bip)->bi_size >> 9) > bi->bi_sector) | |
1262 | goto overlap; | |
1263 | bip = & (*bip)->bi_next; | |
1264 | } | |
1265 | if (*bip && (*bip)->bi_sector < bi->bi_sector + ((bi->bi_size)>>9)) | |
1266 | goto overlap; | |
1267 | ||
78bafebd | 1268 | BUG_ON(*bip && bi->bi_next && (*bip) != bi->bi_next); |
1da177e4 LT |
1269 | if (*bip) |
1270 | bi->bi_next = *bip; | |
1271 | *bip = bi; | |
1272 | bi->bi_phys_segments ++; | |
1273 | spin_unlock_irq(&conf->device_lock); | |
1274 | spin_unlock(&sh->lock); | |
1275 | ||
1276 | PRINTK("added bi b#%llu to stripe s#%llu, disk %d.\n", | |
1277 | (unsigned long long)bi->bi_sector, | |
1278 | (unsigned long long)sh->sector, dd_idx); | |
1279 | ||
72626685 | 1280 | if (conf->mddev->bitmap && firstwrite) { |
72626685 N |
1281 | bitmap_startwrite(conf->mddev->bitmap, sh->sector, |
1282 | STRIPE_SECTORS, 0); | |
ae3c20cc | 1283 | sh->bm_seq = conf->seq_flush+1; |
72626685 N |
1284 | set_bit(STRIPE_BIT_DELAY, &sh->state); |
1285 | } | |
1286 | ||
1da177e4 LT |
1287 | if (forwrite) { |
1288 | /* check if page is covered */ | |
1289 | sector_t sector = sh->dev[dd_idx].sector; | |
1290 | for (bi=sh->dev[dd_idx].towrite; | |
1291 | sector < sh->dev[dd_idx].sector + STRIPE_SECTORS && | |
1292 | bi && bi->bi_sector <= sector; | |
1293 | bi = r5_next_bio(bi, sh->dev[dd_idx].sector)) { | |
1294 | if (bi->bi_sector + (bi->bi_size>>9) >= sector) | |
1295 | sector = bi->bi_sector + (bi->bi_size>>9); | |
1296 | } | |
1297 | if (sector >= sh->dev[dd_idx].sector + STRIPE_SECTORS) | |
1298 | set_bit(R5_OVERWRITE, &sh->dev[dd_idx].flags); | |
1299 | } | |
1300 | return 1; | |
1301 | ||
1302 | overlap: | |
1303 | set_bit(R5_Overlap, &sh->dev[dd_idx].flags); | |
1304 | spin_unlock_irq(&conf->device_lock); | |
1305 | spin_unlock(&sh->lock); | |
1306 | return 0; | |
1307 | } | |
1308 | ||
29269553 N |
1309 | static void end_reshape(raid5_conf_t *conf); |
1310 | ||
16a53ecc N |
1311 | static int page_is_zero(struct page *p) |
1312 | { | |
1313 | char *a = page_address(p); | |
1314 | return ((*(u32*)a) == 0 && | |
1315 | memcmp(a, a+4, STRIPE_SIZE-4)==0); | |
1316 | } | |
1317 | ||
ccfcc3c1 N |
1318 | static int stripe_to_pdidx(sector_t stripe, raid5_conf_t *conf, int disks) |
1319 | { | |
1320 | int sectors_per_chunk = conf->chunk_size >> 9; | |
ccfcc3c1 | 1321 | int pd_idx, dd_idx; |
2d2063ce CQH |
1322 | int chunk_offset = sector_div(stripe, sectors_per_chunk); |
1323 | ||
b875e531 N |
1324 | raid5_compute_sector(stripe * (disks - conf->max_degraded) |
1325 | *sectors_per_chunk + chunk_offset, | |
1326 | disks, disks - conf->max_degraded, | |
1327 | &dd_idx, &pd_idx, conf); | |
ccfcc3c1 N |
1328 | return pd_idx; |
1329 | } | |
1330 | ||
1da177e4 LT |
1331 | |
1332 | /* | |
1333 | * handle_stripe - do things to a stripe. | |
1334 | * | |
1335 | * We lock the stripe and then examine the state of various bits | |
1336 | * to see what needs to be done. | |
1337 | * Possible results: | |
1338 | * return some read request which now have data | |
1339 | * return some write requests which are safely on disc | |
1340 | * schedule a read on some buffers | |
1341 | * schedule a write of some buffers | |
1342 | * return confirmation of parity correctness | |
1343 | * | |
1344 | * Parity calculations are done inside the stripe lock | |
1345 | * buffers are taken off read_list or write_list, and bh_cache buffers | |
1346 | * get BH_Lock set before the stripe lock is released. | |
1347 | * | |
1348 | */ | |
1349 | ||
16a53ecc | 1350 | static void handle_stripe5(struct stripe_head *sh) |
1da177e4 LT |
1351 | { |
1352 | raid5_conf_t *conf = sh->raid_conf; | |
7ecaa1e6 | 1353 | int disks = sh->disks; |
1da177e4 LT |
1354 | struct bio *return_bi= NULL; |
1355 | struct bio *bi; | |
1356 | int i; | |
ccfcc3c1 | 1357 | int syncing, expanding, expanded; |
1da177e4 LT |
1358 | int locked=0, uptodate=0, to_read=0, to_write=0, failed=0, written=0; |
1359 | int non_overwrite = 0; | |
1360 | int failed_num=0; | |
1361 | struct r5dev *dev; | |
1362 | ||
1363 | PRINTK("handling stripe %llu, cnt=%d, pd_idx=%d\n", | |
1364 | (unsigned long long)sh->sector, atomic_read(&sh->count), | |
1365 | sh->pd_idx); | |
1366 | ||
1367 | spin_lock(&sh->lock); | |
1368 | clear_bit(STRIPE_HANDLE, &sh->state); | |
1369 | clear_bit(STRIPE_DELAYED, &sh->state); | |
1370 | ||
1371 | syncing = test_bit(STRIPE_SYNCING, &sh->state); | |
ccfcc3c1 N |
1372 | expanding = test_bit(STRIPE_EXPAND_SOURCE, &sh->state); |
1373 | expanded = test_bit(STRIPE_EXPAND_READY, &sh->state); | |
1da177e4 LT |
1374 | /* Now to look around and see what can be done */ |
1375 | ||
9910f16a | 1376 | rcu_read_lock(); |
1da177e4 LT |
1377 | for (i=disks; i--; ) { |
1378 | mdk_rdev_t *rdev; | |
1379 | dev = &sh->dev[i]; | |
1380 | clear_bit(R5_Insync, &dev->flags); | |
1da177e4 LT |
1381 | |
1382 | PRINTK("check %d: state 0x%lx read %p write %p written %p\n", | |
1383 | i, dev->flags, dev->toread, dev->towrite, dev->written); | |
1384 | /* maybe we can reply to a read */ | |
1385 | if (test_bit(R5_UPTODATE, &dev->flags) && dev->toread) { | |
1386 | struct bio *rbi, *rbi2; | |
1387 | PRINTK("Return read for disc %d\n", i); | |
1388 | spin_lock_irq(&conf->device_lock); | |
1389 | rbi = dev->toread; | |
1390 | dev->toread = NULL; | |
1391 | if (test_and_clear_bit(R5_Overlap, &dev->flags)) | |
1392 | wake_up(&conf->wait_for_overlap); | |
1393 | spin_unlock_irq(&conf->device_lock); | |
1394 | while (rbi && rbi->bi_sector < dev->sector + STRIPE_SECTORS) { | |
1395 | copy_data(0, rbi, dev->page, dev->sector); | |
1396 | rbi2 = r5_next_bio(rbi, dev->sector); | |
1397 | spin_lock_irq(&conf->device_lock); | |
1398 | if (--rbi->bi_phys_segments == 0) { | |
1399 | rbi->bi_next = return_bi; | |
1400 | return_bi = rbi; | |
1401 | } | |
1402 | spin_unlock_irq(&conf->device_lock); | |
1403 | rbi = rbi2; | |
1404 | } | |
1405 | } | |
1406 | ||
1407 | /* now count some things */ | |
1408 | if (test_bit(R5_LOCKED, &dev->flags)) locked++; | |
1409 | if (test_bit(R5_UPTODATE, &dev->flags)) uptodate++; | |
1410 | ||
1411 | ||
1412 | if (dev->toread) to_read++; | |
1413 | if (dev->towrite) { | |
1414 | to_write++; | |
1415 | if (!test_bit(R5_OVERWRITE, &dev->flags)) | |
1416 | non_overwrite++; | |
1417 | } | |
1418 | if (dev->written) written++; | |
9910f16a | 1419 | rdev = rcu_dereference(conf->disks[i].rdev); |
b2d444d7 | 1420 | if (!rdev || !test_bit(In_sync, &rdev->flags)) { |
14f8d26b | 1421 | /* The ReadError flag will just be confusing now */ |
4e5314b5 N |
1422 | clear_bit(R5_ReadError, &dev->flags); |
1423 | clear_bit(R5_ReWrite, &dev->flags); | |
1424 | } | |
b2d444d7 | 1425 | if (!rdev || !test_bit(In_sync, &rdev->flags) |
4e5314b5 | 1426 | || test_bit(R5_ReadError, &dev->flags)) { |
1da177e4 LT |
1427 | failed++; |
1428 | failed_num = i; | |
1429 | } else | |
1430 | set_bit(R5_Insync, &dev->flags); | |
1431 | } | |
9910f16a | 1432 | rcu_read_unlock(); |
1da177e4 LT |
1433 | PRINTK("locked=%d uptodate=%d to_read=%d" |
1434 | " to_write=%d failed=%d failed_num=%d\n", | |
1435 | locked, uptodate, to_read, to_write, failed, failed_num); | |
1436 | /* check if the array has lost two devices and, if so, some requests might | |
1437 | * need to be failed | |
1438 | */ | |
1439 | if (failed > 1 && to_read+to_write+written) { | |
1da177e4 | 1440 | for (i=disks; i--; ) { |
72626685 | 1441 | int bitmap_end = 0; |
4e5314b5 N |
1442 | |
1443 | if (test_bit(R5_ReadError, &sh->dev[i].flags)) { | |
9910f16a N |
1444 | mdk_rdev_t *rdev; |
1445 | rcu_read_lock(); | |
1446 | rdev = rcu_dereference(conf->disks[i].rdev); | |
b2d444d7 | 1447 | if (rdev && test_bit(In_sync, &rdev->flags)) |
4e5314b5 N |
1448 | /* multiple read failures in one stripe */ |
1449 | md_error(conf->mddev, rdev); | |
9910f16a | 1450 | rcu_read_unlock(); |
4e5314b5 N |
1451 | } |
1452 | ||
72626685 | 1453 | spin_lock_irq(&conf->device_lock); |
1da177e4 LT |
1454 | /* fail all writes first */ |
1455 | bi = sh->dev[i].towrite; | |
1456 | sh->dev[i].towrite = NULL; | |
72626685 | 1457 | if (bi) { to_write--; bitmap_end = 1; } |
1da177e4 LT |
1458 | |
1459 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) | |
1460 | wake_up(&conf->wait_for_overlap); | |
1461 | ||
1462 | while (bi && bi->bi_sector < sh->dev[i].sector + STRIPE_SECTORS){ | |
1463 | struct bio *nextbi = r5_next_bio(bi, sh->dev[i].sector); | |
1464 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
1465 | if (--bi->bi_phys_segments == 0) { | |
1466 | md_write_end(conf->mddev); | |
1467 | bi->bi_next = return_bi; | |
1468 | return_bi = bi; | |
1469 | } | |
1470 | bi = nextbi; | |
1471 | } | |
1472 | /* and fail all 'written' */ | |
1473 | bi = sh->dev[i].written; | |
1474 | sh->dev[i].written = NULL; | |
72626685 | 1475 | if (bi) bitmap_end = 1; |
1da177e4 LT |
1476 | while (bi && bi->bi_sector < sh->dev[i].sector + STRIPE_SECTORS) { |
1477 | struct bio *bi2 = r5_next_bio(bi, sh->dev[i].sector); | |
1478 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
1479 | if (--bi->bi_phys_segments == 0) { | |
1480 | md_write_end(conf->mddev); | |
1481 | bi->bi_next = return_bi; | |
1482 | return_bi = bi; | |
1483 | } | |
1484 | bi = bi2; | |
1485 | } | |
1486 | ||
1487 | /* fail any reads if this device is non-operational */ | |
4e5314b5 N |
1488 | if (!test_bit(R5_Insync, &sh->dev[i].flags) || |
1489 | test_bit(R5_ReadError, &sh->dev[i].flags)) { | |
1da177e4 LT |
1490 | bi = sh->dev[i].toread; |
1491 | sh->dev[i].toread = NULL; | |
1492 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) | |
1493 | wake_up(&conf->wait_for_overlap); | |
1494 | if (bi) to_read--; | |
1495 | while (bi && bi->bi_sector < sh->dev[i].sector + STRIPE_SECTORS){ | |
1496 | struct bio *nextbi = r5_next_bio(bi, sh->dev[i].sector); | |
1497 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
1498 | if (--bi->bi_phys_segments == 0) { | |
1499 | bi->bi_next = return_bi; | |
1500 | return_bi = bi; | |
1501 | } | |
1502 | bi = nextbi; | |
1503 | } | |
1504 | } | |
72626685 N |
1505 | spin_unlock_irq(&conf->device_lock); |
1506 | if (bitmap_end) | |
1507 | bitmap_endwrite(conf->mddev->bitmap, sh->sector, | |
1508 | STRIPE_SECTORS, 0, 0); | |
1da177e4 | 1509 | } |
1da177e4 LT |
1510 | } |
1511 | if (failed > 1 && syncing) { | |
1512 | md_done_sync(conf->mddev, STRIPE_SECTORS,0); | |
1513 | clear_bit(STRIPE_SYNCING, &sh->state); | |
1514 | syncing = 0; | |
1515 | } | |
1516 | ||
1517 | /* might be able to return some write requests if the parity block | |
1518 | * is safe, or on a failed drive | |
1519 | */ | |
1520 | dev = &sh->dev[sh->pd_idx]; | |
1521 | if ( written && | |
1522 | ( (test_bit(R5_Insync, &dev->flags) && !test_bit(R5_LOCKED, &dev->flags) && | |
1523 | test_bit(R5_UPTODATE, &dev->flags)) | |
1524 | || (failed == 1 && failed_num == sh->pd_idx)) | |
1525 | ) { | |
1526 | /* any written block on an uptodate or failed drive can be returned. | |
1527 | * Note that if we 'wrote' to a failed drive, it will be UPTODATE, but | |
1528 | * never LOCKED, so we don't need to test 'failed' directly. | |
1529 | */ | |
1530 | for (i=disks; i--; ) | |
1531 | if (sh->dev[i].written) { | |
1532 | dev = &sh->dev[i]; | |
1533 | if (!test_bit(R5_LOCKED, &dev->flags) && | |
1534 | test_bit(R5_UPTODATE, &dev->flags) ) { | |
1535 | /* We can return any write requests */ | |
1536 | struct bio *wbi, *wbi2; | |
72626685 | 1537 | int bitmap_end = 0; |
1da177e4 LT |
1538 | PRINTK("Return write for disc %d\n", i); |
1539 | spin_lock_irq(&conf->device_lock); | |
1540 | wbi = dev->written; | |
1541 | dev->written = NULL; | |
1542 | while (wbi && wbi->bi_sector < dev->sector + STRIPE_SECTORS) { | |
1543 | wbi2 = r5_next_bio(wbi, dev->sector); | |
1544 | if (--wbi->bi_phys_segments == 0) { | |
1545 | md_write_end(conf->mddev); | |
1546 | wbi->bi_next = return_bi; | |
1547 | return_bi = wbi; | |
1548 | } | |
1549 | wbi = wbi2; | |
1550 | } | |
72626685 N |
1551 | if (dev->towrite == NULL) |
1552 | bitmap_end = 1; | |
1da177e4 | 1553 | spin_unlock_irq(&conf->device_lock); |
72626685 N |
1554 | if (bitmap_end) |
1555 | bitmap_endwrite(conf->mddev->bitmap, sh->sector, | |
1556 | STRIPE_SECTORS, | |
1557 | !test_bit(STRIPE_DEGRADED, &sh->state), 0); | |
1da177e4 LT |
1558 | } |
1559 | } | |
1560 | } | |
1561 | ||
1562 | /* Now we might consider reading some blocks, either to check/generate | |
1563 | * parity, or to satisfy requests | |
1564 | * or to load a block that is being partially written. | |
1565 | */ | |
ccfcc3c1 | 1566 | if (to_read || non_overwrite || (syncing && (uptodate < disks)) || expanding) { |
1da177e4 LT |
1567 | for (i=disks; i--;) { |
1568 | dev = &sh->dev[i]; | |
1569 | if (!test_bit(R5_LOCKED, &dev->flags) && !test_bit(R5_UPTODATE, &dev->flags) && | |
1570 | (dev->toread || | |
1571 | (dev->towrite && !test_bit(R5_OVERWRITE, &dev->flags)) || | |
1572 | syncing || | |
ccfcc3c1 | 1573 | expanding || |
1da177e4 LT |
1574 | (failed && (sh->dev[failed_num].toread || |
1575 | (sh->dev[failed_num].towrite && !test_bit(R5_OVERWRITE, &sh->dev[failed_num].flags)))) | |
1576 | ) | |
1577 | ) { | |
1578 | /* we would like to get this block, possibly | |
1579 | * by computing it, but we might not be able to | |
1580 | */ | |
1581 | if (uptodate == disks-1) { | |
1582 | PRINTK("Computing block %d\n", i); | |
1583 | compute_block(sh, i); | |
1584 | uptodate++; | |
1585 | } else if (test_bit(R5_Insync, &dev->flags)) { | |
1586 | set_bit(R5_LOCKED, &dev->flags); | |
1587 | set_bit(R5_Wantread, &dev->flags); | |
1da177e4 LT |
1588 | locked++; |
1589 | PRINTK("Reading block %d (sync=%d)\n", | |
1590 | i, syncing); | |
1da177e4 LT |
1591 | } |
1592 | } | |
1593 | } | |
1594 | set_bit(STRIPE_HANDLE, &sh->state); | |
1595 | } | |
1596 | ||
1597 | /* now to consider writing and what else, if anything should be read */ | |
1598 | if (to_write) { | |
1599 | int rmw=0, rcw=0; | |
1600 | for (i=disks ; i--;) { | |
1601 | /* would I have to read this buffer for read_modify_write */ | |
1602 | dev = &sh->dev[i]; | |
1603 | if ((dev->towrite || i == sh->pd_idx) && | |
1604 | (!test_bit(R5_LOCKED, &dev->flags) | |
1da177e4 LT |
1605 | ) && |
1606 | !test_bit(R5_UPTODATE, &dev->flags)) { | |
1607 | if (test_bit(R5_Insync, &dev->flags) | |
1608 | /* && !(!mddev->insync && i == sh->pd_idx) */ | |
1609 | ) | |
1610 | rmw++; | |
1611 | else rmw += 2*disks; /* cannot read it */ | |
1612 | } | |
1613 | /* Would I have to read this buffer for reconstruct_write */ | |
1614 | if (!test_bit(R5_OVERWRITE, &dev->flags) && i != sh->pd_idx && | |
1615 | (!test_bit(R5_LOCKED, &dev->flags) | |
1da177e4 LT |
1616 | ) && |
1617 | !test_bit(R5_UPTODATE, &dev->flags)) { | |
1618 | if (test_bit(R5_Insync, &dev->flags)) rcw++; | |
1619 | else rcw += 2*disks; | |
1620 | } | |
1621 | } | |
1622 | PRINTK("for sector %llu, rmw=%d rcw=%d\n", | |
1623 | (unsigned long long)sh->sector, rmw, rcw); | |
1624 | set_bit(STRIPE_HANDLE, &sh->state); | |
1625 | if (rmw < rcw && rmw > 0) | |
1626 | /* prefer read-modify-write, but need to get some data */ | |
1627 | for (i=disks; i--;) { | |
1628 | dev = &sh->dev[i]; | |
1629 | if ((dev->towrite || i == sh->pd_idx) && | |
1630 | !test_bit(R5_LOCKED, &dev->flags) && !test_bit(R5_UPTODATE, &dev->flags) && | |
1631 | test_bit(R5_Insync, &dev->flags)) { | |
1632 | if (test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) | |
1633 | { | |
1634 | PRINTK("Read_old block %d for r-m-w\n", i); | |
1635 | set_bit(R5_LOCKED, &dev->flags); | |
1636 | set_bit(R5_Wantread, &dev->flags); | |
1637 | locked++; | |
1638 | } else { | |
1639 | set_bit(STRIPE_DELAYED, &sh->state); | |
1640 | set_bit(STRIPE_HANDLE, &sh->state); | |
1641 | } | |
1642 | } | |
1643 | } | |
1644 | if (rcw <= rmw && rcw > 0) | |
1645 | /* want reconstruct write, but need to get some data */ | |
1646 | for (i=disks; i--;) { | |
1647 | dev = &sh->dev[i]; | |
1648 | if (!test_bit(R5_OVERWRITE, &dev->flags) && i != sh->pd_idx && | |
1649 | !test_bit(R5_LOCKED, &dev->flags) && !test_bit(R5_UPTODATE, &dev->flags) && | |
1650 | test_bit(R5_Insync, &dev->flags)) { | |
1651 | if (test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) | |
1652 | { | |
1653 | PRINTK("Read_old block %d for Reconstruct\n", i); | |
1654 | set_bit(R5_LOCKED, &dev->flags); | |
1655 | set_bit(R5_Wantread, &dev->flags); | |
1656 | locked++; | |
1657 | } else { | |
1658 | set_bit(STRIPE_DELAYED, &sh->state); | |
1659 | set_bit(STRIPE_HANDLE, &sh->state); | |
1660 | } | |
1661 | } | |
1662 | } | |
1663 | /* now if nothing is locked, and if we have enough data, we can start a write request */ | |
72626685 N |
1664 | if (locked == 0 && (rcw == 0 ||rmw == 0) && |
1665 | !test_bit(STRIPE_BIT_DELAY, &sh->state)) { | |
1da177e4 | 1666 | PRINTK("Computing parity...\n"); |
16a53ecc | 1667 | compute_parity5(sh, rcw==0 ? RECONSTRUCT_WRITE : READ_MODIFY_WRITE); |
1da177e4 LT |
1668 | /* now every locked buffer is ready to be written */ |
1669 | for (i=disks; i--;) | |
1670 | if (test_bit(R5_LOCKED, &sh->dev[i].flags)) { | |
1671 | PRINTK("Writing block %d\n", i); | |
1672 | locked++; | |
1673 | set_bit(R5_Wantwrite, &sh->dev[i].flags); | |
1674 | if (!test_bit(R5_Insync, &sh->dev[i].flags) | |
1675 | || (i==sh->pd_idx && failed == 0)) | |
1676 | set_bit(STRIPE_INSYNC, &sh->state); | |
1677 | } | |
1678 | if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
1679 | atomic_dec(&conf->preread_active_stripes); | |
1680 | if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD) | |
1681 | md_wakeup_thread(conf->mddev->thread); | |
1682 | } | |
1683 | } | |
1684 | } | |
1685 | ||
1686 | /* maybe we need to check and possibly fix the parity for this stripe | |
1687 | * Any reads will already have been scheduled, so we just see if enough data | |
1688 | * is available | |
1689 | */ | |
1690 | if (syncing && locked == 0 && | |
14f8d26b | 1691 | !test_bit(STRIPE_INSYNC, &sh->state)) { |
1da177e4 LT |
1692 | set_bit(STRIPE_HANDLE, &sh->state); |
1693 | if (failed == 0) { | |
78bafebd | 1694 | BUG_ON(uptodate != disks); |
16a53ecc | 1695 | compute_parity5(sh, CHECK_PARITY); |
1da177e4 | 1696 | uptodate--; |
16a53ecc | 1697 | if (page_is_zero(sh->dev[sh->pd_idx].page)) { |
1da177e4 LT |
1698 | /* parity is correct (on disc, not in buffer any more) */ |
1699 | set_bit(STRIPE_INSYNC, &sh->state); | |
9d88883e N |
1700 | } else { |
1701 | conf->mddev->resync_mismatches += STRIPE_SECTORS; | |
1702 | if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery)) | |
1703 | /* don't try to repair!! */ | |
1704 | set_bit(STRIPE_INSYNC, &sh->state); | |
14f8d26b N |
1705 | else { |
1706 | compute_block(sh, sh->pd_idx); | |
1707 | uptodate++; | |
1708 | } | |
1da177e4 LT |
1709 | } |
1710 | } | |
1711 | if (!test_bit(STRIPE_INSYNC, &sh->state)) { | |
14f8d26b | 1712 | /* either failed parity check, or recovery is happening */ |
1da177e4 LT |
1713 | if (failed==0) |
1714 | failed_num = sh->pd_idx; | |
1da177e4 | 1715 | dev = &sh->dev[failed_num]; |
14f8d26b N |
1716 | BUG_ON(!test_bit(R5_UPTODATE, &dev->flags)); |
1717 | BUG_ON(uptodate != disks); | |
1718 | ||
1da177e4 LT |
1719 | set_bit(R5_LOCKED, &dev->flags); |
1720 | set_bit(R5_Wantwrite, &dev->flags); | |
72626685 | 1721 | clear_bit(STRIPE_DEGRADED, &sh->state); |
1da177e4 LT |
1722 | locked++; |
1723 | set_bit(STRIPE_INSYNC, &sh->state); | |
1da177e4 LT |
1724 | } |
1725 | } | |
1726 | if (syncing && locked == 0 && test_bit(STRIPE_INSYNC, &sh->state)) { | |
1727 | md_done_sync(conf->mddev, STRIPE_SECTORS,1); | |
1728 | clear_bit(STRIPE_SYNCING, &sh->state); | |
1729 | } | |
4e5314b5 N |
1730 | |
1731 | /* If the failed drive is just a ReadError, then we might need to progress | |
1732 | * the repair/check process | |
1733 | */ | |
ba22dcbf N |
1734 | if (failed == 1 && ! conf->mddev->ro && |
1735 | test_bit(R5_ReadError, &sh->dev[failed_num].flags) | |
4e5314b5 N |
1736 | && !test_bit(R5_LOCKED, &sh->dev[failed_num].flags) |
1737 | && test_bit(R5_UPTODATE, &sh->dev[failed_num].flags) | |
1738 | ) { | |
1739 | dev = &sh->dev[failed_num]; | |
1740 | if (!test_bit(R5_ReWrite, &dev->flags)) { | |
1741 | set_bit(R5_Wantwrite, &dev->flags); | |
1742 | set_bit(R5_ReWrite, &dev->flags); | |
1743 | set_bit(R5_LOCKED, &dev->flags); | |
ccfcc3c1 | 1744 | locked++; |
4e5314b5 N |
1745 | } else { |
1746 | /* let's read it back */ | |
1747 | set_bit(R5_Wantread, &dev->flags); | |
1748 | set_bit(R5_LOCKED, &dev->flags); | |
ccfcc3c1 | 1749 | locked++; |
4e5314b5 N |
1750 | } |
1751 | } | |
1752 | ||
ccfcc3c1 N |
1753 | if (expanded && test_bit(STRIPE_EXPANDING, &sh->state)) { |
1754 | /* Need to write out all blocks after computing parity */ | |
1755 | sh->disks = conf->raid_disks; | |
1756 | sh->pd_idx = stripe_to_pdidx(sh->sector, conf, conf->raid_disks); | |
16a53ecc | 1757 | compute_parity5(sh, RECONSTRUCT_WRITE); |
ccfcc3c1 N |
1758 | for (i= conf->raid_disks; i--;) { |
1759 | set_bit(R5_LOCKED, &sh->dev[i].flags); | |
1760 | locked++; | |
1761 | set_bit(R5_Wantwrite, &sh->dev[i].flags); | |
1762 | } | |
1763 | clear_bit(STRIPE_EXPANDING, &sh->state); | |
1764 | } else if (expanded) { | |
1765 | clear_bit(STRIPE_EXPAND_READY, &sh->state); | |
f6705578 | 1766 | atomic_dec(&conf->reshape_stripes); |
ccfcc3c1 N |
1767 | wake_up(&conf->wait_for_overlap); |
1768 | md_done_sync(conf->mddev, STRIPE_SECTORS, 1); | |
1769 | } | |
1770 | ||
1771 | if (expanding && locked == 0) { | |
1772 | /* We have read all the blocks in this stripe and now we need to | |
1773 | * copy some of them into a target stripe for expand. | |
1774 | */ | |
1775 | clear_bit(STRIPE_EXPAND_SOURCE, &sh->state); | |
1776 | for (i=0; i< sh->disks; i++) | |
1777 | if (i != sh->pd_idx) { | |
1778 | int dd_idx, pd_idx, j; | |
1779 | struct stripe_head *sh2; | |
1780 | ||
1781 | sector_t bn = compute_blocknr(sh, i); | |
1782 | sector_t s = raid5_compute_sector(bn, conf->raid_disks, | |
1783 | conf->raid_disks-1, | |
1784 | &dd_idx, &pd_idx, conf); | |
1785 | sh2 = get_active_stripe(conf, s, conf->raid_disks, pd_idx, 1); | |
1786 | if (sh2 == NULL) | |
1787 | /* so far only the early blocks of this stripe | |
1788 | * have been requested. When later blocks | |
1789 | * get requested, we will try again | |
1790 | */ | |
1791 | continue; | |
1792 | if(!test_bit(STRIPE_EXPANDING, &sh2->state) || | |
1793 | test_bit(R5_Expanded, &sh2->dev[dd_idx].flags)) { | |
1794 | /* must have already done this block */ | |
1795 | release_stripe(sh2); | |
1796 | continue; | |
1797 | } | |
1798 | memcpy(page_address(sh2->dev[dd_idx].page), | |
1799 | page_address(sh->dev[i].page), | |
1800 | STRIPE_SIZE); | |
1801 | set_bit(R5_Expanded, &sh2->dev[dd_idx].flags); | |
1802 | set_bit(R5_UPTODATE, &sh2->dev[dd_idx].flags); | |
1803 | for (j=0; j<conf->raid_disks; j++) | |
1804 | if (j != sh2->pd_idx && | |
1805 | !test_bit(R5_Expanded, &sh2->dev[j].flags)) | |
1806 | break; | |
1807 | if (j == conf->raid_disks) { | |
1808 | set_bit(STRIPE_EXPAND_READY, &sh2->state); | |
1809 | set_bit(STRIPE_HANDLE, &sh2->state); | |
1810 | } | |
1811 | release_stripe(sh2); | |
1812 | } | |
1813 | } | |
1814 | ||
1da177e4 LT |
1815 | spin_unlock(&sh->lock); |
1816 | ||
1817 | while ((bi=return_bi)) { | |
1818 | int bytes = bi->bi_size; | |
1819 | ||
1820 | return_bi = bi->bi_next; | |
1821 | bi->bi_next = NULL; | |
1822 | bi->bi_size = 0; | |
c2b00852 N |
1823 | bi->bi_end_io(bi, bytes, |
1824 | test_bit(BIO_UPTODATE, &bi->bi_flags) | |
1825 | ? 0 : -EIO); | |
1da177e4 LT |
1826 | } |
1827 | for (i=disks; i-- ;) { | |
1828 | int rw; | |
1829 | struct bio *bi; | |
1830 | mdk_rdev_t *rdev; | |
1831 | if (test_and_clear_bit(R5_Wantwrite, &sh->dev[i].flags)) | |
802ba064 | 1832 | rw = WRITE; |
1da177e4 | 1833 | else if (test_and_clear_bit(R5_Wantread, &sh->dev[i].flags)) |
802ba064 | 1834 | rw = READ; |
1da177e4 LT |
1835 | else |
1836 | continue; | |
1837 | ||
1838 | bi = &sh->dev[i].req; | |
1839 | ||
1840 | bi->bi_rw = rw; | |
802ba064 | 1841 | if (rw == WRITE) |
1da177e4 LT |
1842 | bi->bi_end_io = raid5_end_write_request; |
1843 | else | |
1844 | bi->bi_end_io = raid5_end_read_request; | |
1845 | ||
1846 | rcu_read_lock(); | |
d6065f7b | 1847 | rdev = rcu_dereference(conf->disks[i].rdev); |
b2d444d7 | 1848 | if (rdev && test_bit(Faulty, &rdev->flags)) |
1da177e4 LT |
1849 | rdev = NULL; |
1850 | if (rdev) | |
1851 | atomic_inc(&rdev->nr_pending); | |
1852 | rcu_read_unlock(); | |
1853 | ||
1854 | if (rdev) { | |
ccfcc3c1 | 1855 | if (syncing || expanding || expanded) |
1da177e4 LT |
1856 | md_sync_acct(rdev->bdev, STRIPE_SECTORS); |
1857 | ||
1858 | bi->bi_bdev = rdev->bdev; | |
1859 | PRINTK("for %llu schedule op %ld on disc %d\n", | |
1860 | (unsigned long long)sh->sector, bi->bi_rw, i); | |
1861 | atomic_inc(&sh->count); | |
1862 | bi->bi_sector = sh->sector + rdev->data_offset; | |
1863 | bi->bi_flags = 1 << BIO_UPTODATE; | |
1864 | bi->bi_vcnt = 1; | |
1865 | bi->bi_max_vecs = 1; | |
1866 | bi->bi_idx = 0; | |
1867 | bi->bi_io_vec = &sh->dev[i].vec; | |
1868 | bi->bi_io_vec[0].bv_len = STRIPE_SIZE; | |
1869 | bi->bi_io_vec[0].bv_offset = 0; | |
1870 | bi->bi_size = STRIPE_SIZE; | |
1871 | bi->bi_next = NULL; | |
4dbcdc75 N |
1872 | if (rw == WRITE && |
1873 | test_bit(R5_ReWrite, &sh->dev[i].flags)) | |
1874 | atomic_add(STRIPE_SECTORS, &rdev->corrected_errors); | |
1da177e4 LT |
1875 | generic_make_request(bi); |
1876 | } else { | |
802ba064 | 1877 | if (rw == WRITE) |
72626685 | 1878 | set_bit(STRIPE_DEGRADED, &sh->state); |
1da177e4 LT |
1879 | PRINTK("skip op %ld on disc %d for sector %llu\n", |
1880 | bi->bi_rw, i, (unsigned long long)sh->sector); | |
1881 | clear_bit(R5_LOCKED, &sh->dev[i].flags); | |
1882 | set_bit(STRIPE_HANDLE, &sh->state); | |
1883 | } | |
1884 | } | |
1885 | } | |
1886 | ||
16a53ecc | 1887 | static void handle_stripe6(struct stripe_head *sh, struct page *tmp_page) |
1da177e4 | 1888 | { |
16a53ecc N |
1889 | raid6_conf_t *conf = sh->raid_conf; |
1890 | int disks = conf->raid_disks; | |
1891 | struct bio *return_bi= NULL; | |
1892 | struct bio *bi; | |
1893 | int i; | |
1894 | int syncing; | |
1895 | int locked=0, uptodate=0, to_read=0, to_write=0, failed=0, written=0; | |
1896 | int non_overwrite = 0; | |
1897 | int failed_num[2] = {0, 0}; | |
1898 | struct r5dev *dev, *pdev, *qdev; | |
1899 | int pd_idx = sh->pd_idx; | |
1900 | int qd_idx = raid6_next_disk(pd_idx, disks); | |
1901 | int p_failed, q_failed; | |
1da177e4 | 1902 | |
16a53ecc N |
1903 | PRINTK("handling stripe %llu, state=%#lx cnt=%d, pd_idx=%d, qd_idx=%d\n", |
1904 | (unsigned long long)sh->sector, sh->state, atomic_read(&sh->count), | |
1905 | pd_idx, qd_idx); | |
72626685 | 1906 | |
16a53ecc N |
1907 | spin_lock(&sh->lock); |
1908 | clear_bit(STRIPE_HANDLE, &sh->state); | |
1909 | clear_bit(STRIPE_DELAYED, &sh->state); | |
1910 | ||
1911 | syncing = test_bit(STRIPE_SYNCING, &sh->state); | |
1912 | /* Now to look around and see what can be done */ | |
1da177e4 LT |
1913 | |
1914 | rcu_read_lock(); | |
16a53ecc N |
1915 | for (i=disks; i--; ) { |
1916 | mdk_rdev_t *rdev; | |
1917 | dev = &sh->dev[i]; | |
1918 | clear_bit(R5_Insync, &dev->flags); | |
1da177e4 | 1919 | |
16a53ecc N |
1920 | PRINTK("check %d: state 0x%lx read %p write %p written %p\n", |
1921 | i, dev->flags, dev->toread, dev->towrite, dev->written); | |
1922 | /* maybe we can reply to a read */ | |
1923 | if (test_bit(R5_UPTODATE, &dev->flags) && dev->toread) { | |
1924 | struct bio *rbi, *rbi2; | |
1925 | PRINTK("Return read for disc %d\n", i); | |
1926 | spin_lock_irq(&conf->device_lock); | |
1927 | rbi = dev->toread; | |
1928 | dev->toread = NULL; | |
1929 | if (test_and_clear_bit(R5_Overlap, &dev->flags)) | |
1930 | wake_up(&conf->wait_for_overlap); | |
1931 | spin_unlock_irq(&conf->device_lock); | |
1932 | while (rbi && rbi->bi_sector < dev->sector + STRIPE_SECTORS) { | |
1933 | copy_data(0, rbi, dev->page, dev->sector); | |
1934 | rbi2 = r5_next_bio(rbi, dev->sector); | |
1935 | spin_lock_irq(&conf->device_lock); | |
1936 | if (--rbi->bi_phys_segments == 0) { | |
1937 | rbi->bi_next = return_bi; | |
1938 | return_bi = rbi; | |
1939 | } | |
1940 | spin_unlock_irq(&conf->device_lock); | |
1941 | rbi = rbi2; | |
1942 | } | |
1943 | } | |
1da177e4 | 1944 | |
16a53ecc N |
1945 | /* now count some things */ |
1946 | if (test_bit(R5_LOCKED, &dev->flags)) locked++; | |
1947 | if (test_bit(R5_UPTODATE, &dev->flags)) uptodate++; | |
1da177e4 | 1948 | |
16a53ecc N |
1949 | |
1950 | if (dev->toread) to_read++; | |
1951 | if (dev->towrite) { | |
1952 | to_write++; | |
1953 | if (!test_bit(R5_OVERWRITE, &dev->flags)) | |
1954 | non_overwrite++; | |
1955 | } | |
1956 | if (dev->written) written++; | |
1957 | rdev = rcu_dereference(conf->disks[i].rdev); | |
1958 | if (!rdev || !test_bit(In_sync, &rdev->flags)) { | |
1959 | /* The ReadError flag will just be confusing now */ | |
1960 | clear_bit(R5_ReadError, &dev->flags); | |
1961 | clear_bit(R5_ReWrite, &dev->flags); | |
1da177e4 | 1962 | } |
16a53ecc N |
1963 | if (!rdev || !test_bit(In_sync, &rdev->flags) |
1964 | || test_bit(R5_ReadError, &dev->flags)) { | |
1965 | if ( failed < 2 ) | |
1966 | failed_num[failed] = i; | |
1967 | failed++; | |
1968 | } else | |
1969 | set_bit(R5_Insync, &dev->flags); | |
1da177e4 LT |
1970 | } |
1971 | rcu_read_unlock(); | |
16a53ecc N |
1972 | PRINTK("locked=%d uptodate=%d to_read=%d" |
1973 | " to_write=%d failed=%d failed_num=%d,%d\n", | |
1974 | locked, uptodate, to_read, to_write, failed, | |
1975 | failed_num[0], failed_num[1]); | |
1976 | /* check if the array has lost >2 devices and, if so, some requests might | |
1977 | * need to be failed | |
1978 | */ | |
1979 | if (failed > 2 && to_read+to_write+written) { | |
1980 | for (i=disks; i--; ) { | |
1981 | int bitmap_end = 0; | |
1da177e4 | 1982 | |
16a53ecc N |
1983 | if (test_bit(R5_ReadError, &sh->dev[i].flags)) { |
1984 | mdk_rdev_t *rdev; | |
1985 | rcu_read_lock(); | |
1986 | rdev = rcu_dereference(conf->disks[i].rdev); | |
1987 | if (rdev && test_bit(In_sync, &rdev->flags)) | |
1988 | /* multiple read failures in one stripe */ | |
1989 | md_error(conf->mddev, rdev); | |
1990 | rcu_read_unlock(); | |
1991 | } | |
1da177e4 | 1992 | |
16a53ecc N |
1993 | spin_lock_irq(&conf->device_lock); |
1994 | /* fail all writes first */ | |
1995 | bi = sh->dev[i].towrite; | |
1996 | sh->dev[i].towrite = NULL; | |
1997 | if (bi) { to_write--; bitmap_end = 1; } | |
1da177e4 | 1998 | |
16a53ecc N |
1999 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) |
2000 | wake_up(&conf->wait_for_overlap); | |
2001 | ||
2002 | while (bi && bi->bi_sector < sh->dev[i].sector + STRIPE_SECTORS){ | |
2003 | struct bio *nextbi = r5_next_bio(bi, sh->dev[i].sector); | |
2004 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
2005 | if (--bi->bi_phys_segments == 0) { | |
2006 | md_write_end(conf->mddev); | |
2007 | bi->bi_next = return_bi; | |
2008 | return_bi = bi; | |
2009 | } | |
2010 | bi = nextbi; | |
2011 | } | |
2012 | /* and fail all 'written' */ | |
2013 | bi = sh->dev[i].written; | |
2014 | sh->dev[i].written = NULL; | |
2015 | if (bi) bitmap_end = 1; | |
2016 | while (bi && bi->bi_sector < sh->dev[i].sector + STRIPE_SECTORS) { | |
2017 | struct bio *bi2 = r5_next_bio(bi, sh->dev[i].sector); | |
2018 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
2019 | if (--bi->bi_phys_segments == 0) { | |
2020 | md_write_end(conf->mddev); | |
2021 | bi->bi_next = return_bi; | |
2022 | return_bi = bi; | |
2023 | } | |
2024 | bi = bi2; | |
2025 | } | |
2026 | ||
2027 | /* fail any reads if this device is non-operational */ | |
2028 | if (!test_bit(R5_Insync, &sh->dev[i].flags) || | |
2029 | test_bit(R5_ReadError, &sh->dev[i].flags)) { | |
2030 | bi = sh->dev[i].toread; | |
2031 | sh->dev[i].toread = NULL; | |
2032 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) | |
2033 | wake_up(&conf->wait_for_overlap); | |
2034 | if (bi) to_read--; | |
2035 | while (bi && bi->bi_sector < sh->dev[i].sector + STRIPE_SECTORS){ | |
2036 | struct bio *nextbi = r5_next_bio(bi, sh->dev[i].sector); | |
2037 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
2038 | if (--bi->bi_phys_segments == 0) { | |
2039 | bi->bi_next = return_bi; | |
2040 | return_bi = bi; | |
2041 | } | |
2042 | bi = nextbi; | |
2043 | } | |
2044 | } | |
2045 | spin_unlock_irq(&conf->device_lock); | |
2046 | if (bitmap_end) | |
2047 | bitmap_endwrite(conf->mddev->bitmap, sh->sector, | |
2048 | STRIPE_SECTORS, 0, 0); | |
2049 | } | |
2050 | } | |
2051 | if (failed > 2 && syncing) { | |
2052 | md_done_sync(conf->mddev, STRIPE_SECTORS,0); | |
2053 | clear_bit(STRIPE_SYNCING, &sh->state); | |
2054 | syncing = 0; | |
2055 | } | |
2056 | ||
2057 | /* | |
2058 | * might be able to return some write requests if the parity blocks | |
2059 | * are safe, or on a failed drive | |
2060 | */ | |
2061 | pdev = &sh->dev[pd_idx]; | |
2062 | p_failed = (failed >= 1 && failed_num[0] == pd_idx) | |
2063 | || (failed >= 2 && failed_num[1] == pd_idx); | |
2064 | qdev = &sh->dev[qd_idx]; | |
2065 | q_failed = (failed >= 1 && failed_num[0] == qd_idx) | |
2066 | || (failed >= 2 && failed_num[1] == qd_idx); | |
2067 | ||
2068 | if ( written && | |
2069 | ( p_failed || ((test_bit(R5_Insync, &pdev->flags) | |
2070 | && !test_bit(R5_LOCKED, &pdev->flags) | |
2071 | && test_bit(R5_UPTODATE, &pdev->flags))) ) && | |
2072 | ( q_failed || ((test_bit(R5_Insync, &qdev->flags) | |
2073 | && !test_bit(R5_LOCKED, &qdev->flags) | |
2074 | && test_bit(R5_UPTODATE, &qdev->flags))) ) ) { | |
2075 | /* any written block on an uptodate or failed drive can be | |
2076 | * returned. Note that if we 'wrote' to a failed drive, | |
2077 | * it will be UPTODATE, but never LOCKED, so we don't need | |
2078 | * to test 'failed' directly. | |
2079 | */ | |
2080 | for (i=disks; i--; ) | |
2081 | if (sh->dev[i].written) { | |
2082 | dev = &sh->dev[i]; | |
2083 | if (!test_bit(R5_LOCKED, &dev->flags) && | |
2084 | test_bit(R5_UPTODATE, &dev->flags) ) { | |
2085 | /* We can return any write requests */ | |
2086 | int bitmap_end = 0; | |
2087 | struct bio *wbi, *wbi2; | |
2088 | PRINTK("Return write for stripe %llu disc %d\n", | |
2089 | (unsigned long long)sh->sector, i); | |
2090 | spin_lock_irq(&conf->device_lock); | |
2091 | wbi = dev->written; | |
2092 | dev->written = NULL; | |
2093 | while (wbi && wbi->bi_sector < dev->sector + STRIPE_SECTORS) { | |
2094 | wbi2 = r5_next_bio(wbi, dev->sector); | |
2095 | if (--wbi->bi_phys_segments == 0) { | |
2096 | md_write_end(conf->mddev); | |
2097 | wbi->bi_next = return_bi; | |
2098 | return_bi = wbi; | |
2099 | } | |
2100 | wbi = wbi2; | |
2101 | } | |
2102 | if (dev->towrite == NULL) | |
2103 | bitmap_end = 1; | |
2104 | spin_unlock_irq(&conf->device_lock); | |
2105 | if (bitmap_end) | |
2106 | bitmap_endwrite(conf->mddev->bitmap, sh->sector, | |
2107 | STRIPE_SECTORS, | |
2108 | !test_bit(STRIPE_DEGRADED, &sh->state), 0); | |
2109 | } | |
2110 | } | |
2111 | } | |
2112 | ||
2113 | /* Now we might consider reading some blocks, either to check/generate | |
2114 | * parity, or to satisfy requests | |
2115 | * or to load a block that is being partially written. | |
2116 | */ | |
2117 | if (to_read || non_overwrite || (to_write && failed) || (syncing && (uptodate < disks))) { | |
2118 | for (i=disks; i--;) { | |
2119 | dev = &sh->dev[i]; | |
2120 | if (!test_bit(R5_LOCKED, &dev->flags) && !test_bit(R5_UPTODATE, &dev->flags) && | |
2121 | (dev->toread || | |
2122 | (dev->towrite && !test_bit(R5_OVERWRITE, &dev->flags)) || | |
2123 | syncing || | |
2124 | (failed >= 1 && (sh->dev[failed_num[0]].toread || to_write)) || | |
2125 | (failed >= 2 && (sh->dev[failed_num[1]].toread || to_write)) | |
2126 | ) | |
2127 | ) { | |
2128 | /* we would like to get this block, possibly | |
2129 | * by computing it, but we might not be able to | |
2130 | */ | |
2131 | if (uptodate == disks-1) { | |
2132 | PRINTK("Computing stripe %llu block %d\n", | |
2133 | (unsigned long long)sh->sector, i); | |
2134 | compute_block_1(sh, i, 0); | |
2135 | uptodate++; | |
2136 | } else if ( uptodate == disks-2 && failed >= 2 ) { | |
2137 | /* Computing 2-failure is *very* expensive; only do it if failed >= 2 */ | |
2138 | int other; | |
2139 | for (other=disks; other--;) { | |
2140 | if ( other == i ) | |
2141 | continue; | |
2142 | if ( !test_bit(R5_UPTODATE, &sh->dev[other].flags) ) | |
2143 | break; | |
2144 | } | |
2145 | BUG_ON(other < 0); | |
2146 | PRINTK("Computing stripe %llu blocks %d,%d\n", | |
2147 | (unsigned long long)sh->sector, i, other); | |
2148 | compute_block_2(sh, i, other); | |
2149 | uptodate += 2; | |
2150 | } else if (test_bit(R5_Insync, &dev->flags)) { | |
2151 | set_bit(R5_LOCKED, &dev->flags); | |
2152 | set_bit(R5_Wantread, &dev->flags); | |
16a53ecc N |
2153 | locked++; |
2154 | PRINTK("Reading block %d (sync=%d)\n", | |
2155 | i, syncing); | |
2156 | } | |
2157 | } | |
2158 | } | |
2159 | set_bit(STRIPE_HANDLE, &sh->state); | |
2160 | } | |
2161 | ||
2162 | /* now to consider writing and what else, if anything should be read */ | |
2163 | if (to_write) { | |
2164 | int rcw=0, must_compute=0; | |
2165 | for (i=disks ; i--;) { | |
2166 | dev = &sh->dev[i]; | |
2167 | /* Would I have to read this buffer for reconstruct_write */ | |
2168 | if (!test_bit(R5_OVERWRITE, &dev->flags) | |
2169 | && i != pd_idx && i != qd_idx | |
2170 | && (!test_bit(R5_LOCKED, &dev->flags) | |
16a53ecc N |
2171 | ) && |
2172 | !test_bit(R5_UPTODATE, &dev->flags)) { | |
2173 | if (test_bit(R5_Insync, &dev->flags)) rcw++; | |
2174 | else { | |
2175 | PRINTK("raid6: must_compute: disk %d flags=%#lx\n", i, dev->flags); | |
2176 | must_compute++; | |
2177 | } | |
2178 | } | |
2179 | } | |
2180 | PRINTK("for sector %llu, rcw=%d, must_compute=%d\n", | |
2181 | (unsigned long long)sh->sector, rcw, must_compute); | |
2182 | set_bit(STRIPE_HANDLE, &sh->state); | |
2183 | ||
2184 | if (rcw > 0) | |
2185 | /* want reconstruct write, but need to get some data */ | |
2186 | for (i=disks; i--;) { | |
2187 | dev = &sh->dev[i]; | |
2188 | if (!test_bit(R5_OVERWRITE, &dev->flags) | |
2189 | && !(failed == 0 && (i == pd_idx || i == qd_idx)) | |
2190 | && !test_bit(R5_LOCKED, &dev->flags) && !test_bit(R5_UPTODATE, &dev->flags) && | |
2191 | test_bit(R5_Insync, &dev->flags)) { | |
2192 | if (test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) | |
2193 | { | |
2194 | PRINTK("Read_old stripe %llu block %d for Reconstruct\n", | |
2195 | (unsigned long long)sh->sector, i); | |
2196 | set_bit(R5_LOCKED, &dev->flags); | |
2197 | set_bit(R5_Wantread, &dev->flags); | |
2198 | locked++; | |
2199 | } else { | |
2200 | PRINTK("Request delayed stripe %llu block %d for Reconstruct\n", | |
2201 | (unsigned long long)sh->sector, i); | |
2202 | set_bit(STRIPE_DELAYED, &sh->state); | |
2203 | set_bit(STRIPE_HANDLE, &sh->state); | |
2204 | } | |
2205 | } | |
2206 | } | |
2207 | /* now if nothing is locked, and if we have enough data, we can start a write request */ | |
2208 | if (locked == 0 && rcw == 0 && | |
2209 | !test_bit(STRIPE_BIT_DELAY, &sh->state)) { | |
2210 | if ( must_compute > 0 ) { | |
2211 | /* We have failed blocks and need to compute them */ | |
2212 | switch ( failed ) { | |
2213 | case 0: BUG(); | |
2214 | case 1: compute_block_1(sh, failed_num[0], 0); break; | |
2215 | case 2: compute_block_2(sh, failed_num[0], failed_num[1]); break; | |
2216 | default: BUG(); /* This request should have been failed? */ | |
2217 | } | |
2218 | } | |
2219 | ||
2220 | PRINTK("Computing parity for stripe %llu\n", (unsigned long long)sh->sector); | |
2221 | compute_parity6(sh, RECONSTRUCT_WRITE); | |
2222 | /* now every locked buffer is ready to be written */ | |
2223 | for (i=disks; i--;) | |
2224 | if (test_bit(R5_LOCKED, &sh->dev[i].flags)) { | |
2225 | PRINTK("Writing stripe %llu block %d\n", | |
2226 | (unsigned long long)sh->sector, i); | |
2227 | locked++; | |
2228 | set_bit(R5_Wantwrite, &sh->dev[i].flags); | |
2229 | } | |
2230 | /* after a RECONSTRUCT_WRITE, the stripe MUST be in-sync */ | |
2231 | set_bit(STRIPE_INSYNC, &sh->state); | |
2232 | ||
2233 | if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
2234 | atomic_dec(&conf->preread_active_stripes); | |
2235 | if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD) | |
2236 | md_wakeup_thread(conf->mddev->thread); | |
2237 | } | |
2238 | } | |
2239 | } | |
2240 | ||
2241 | /* maybe we need to check and possibly fix the parity for this stripe | |
2242 | * Any reads will already have been scheduled, so we just see if enough data | |
2243 | * is available | |
2244 | */ | |
2245 | if (syncing && locked == 0 && !test_bit(STRIPE_INSYNC, &sh->state)) { | |
2246 | int update_p = 0, update_q = 0; | |
2247 | struct r5dev *dev; | |
2248 | ||
2249 | set_bit(STRIPE_HANDLE, &sh->state); | |
2250 | ||
2251 | BUG_ON(failed>2); | |
2252 | BUG_ON(uptodate < disks); | |
2253 | /* Want to check and possibly repair P and Q. | |
2254 | * However there could be one 'failed' device, in which | |
2255 | * case we can only check one of them, possibly using the | |
2256 | * other to generate missing data | |
2257 | */ | |
2258 | ||
2259 | /* If !tmp_page, we cannot do the calculations, | |
2260 | * but as we have set STRIPE_HANDLE, we will soon be called | |
2261 | * by stripe_handle with a tmp_page - just wait until then. | |
2262 | */ | |
2263 | if (tmp_page) { | |
2264 | if (failed == q_failed) { | |
2265 | /* The only possible failed device holds 'Q', so it makes | |
2266 | * sense to check P (If anything else were failed, we would | |
2267 | * have used P to recreate it). | |
2268 | */ | |
2269 | compute_block_1(sh, pd_idx, 1); | |
2270 | if (!page_is_zero(sh->dev[pd_idx].page)) { | |
2271 | compute_block_1(sh,pd_idx,0); | |
2272 | update_p = 1; | |
2273 | } | |
2274 | } | |
2275 | if (!q_failed && failed < 2) { | |
2276 | /* q is not failed, and we didn't use it to generate | |
2277 | * anything, so it makes sense to check it | |
2278 | */ | |
2279 | memcpy(page_address(tmp_page), | |
2280 | page_address(sh->dev[qd_idx].page), | |
2281 | STRIPE_SIZE); | |
2282 | compute_parity6(sh, UPDATE_PARITY); | |
2283 | if (memcmp(page_address(tmp_page), | |
2284 | page_address(sh->dev[qd_idx].page), | |
2285 | STRIPE_SIZE)!= 0) { | |
2286 | clear_bit(STRIPE_INSYNC, &sh->state); | |
2287 | update_q = 1; | |
2288 | } | |
2289 | } | |
2290 | if (update_p || update_q) { | |
2291 | conf->mddev->resync_mismatches += STRIPE_SECTORS; | |
2292 | if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery)) | |
2293 | /* don't try to repair!! */ | |
2294 | update_p = update_q = 0; | |
2295 | } | |
2296 | ||
2297 | /* now write out any block on a failed drive, | |
2298 | * or P or Q if they need it | |
2299 | */ | |
2300 | ||
2301 | if (failed == 2) { | |
2302 | dev = &sh->dev[failed_num[1]]; | |
2303 | locked++; | |
2304 | set_bit(R5_LOCKED, &dev->flags); | |
2305 | set_bit(R5_Wantwrite, &dev->flags); | |
2306 | } | |
2307 | if (failed >= 1) { | |
2308 | dev = &sh->dev[failed_num[0]]; | |
2309 | locked++; | |
2310 | set_bit(R5_LOCKED, &dev->flags); | |
2311 | set_bit(R5_Wantwrite, &dev->flags); | |
2312 | } | |
2313 | ||
2314 | if (update_p) { | |
2315 | dev = &sh->dev[pd_idx]; | |
2316 | locked ++; | |
2317 | set_bit(R5_LOCKED, &dev->flags); | |
2318 | set_bit(R5_Wantwrite, &dev->flags); | |
2319 | } | |
2320 | if (update_q) { | |
2321 | dev = &sh->dev[qd_idx]; | |
2322 | locked++; | |
2323 | set_bit(R5_LOCKED, &dev->flags); | |
2324 | set_bit(R5_Wantwrite, &dev->flags); | |
2325 | } | |
2326 | clear_bit(STRIPE_DEGRADED, &sh->state); | |
2327 | ||
2328 | set_bit(STRIPE_INSYNC, &sh->state); | |
2329 | } | |
2330 | } | |
2331 | ||
2332 | if (syncing && locked == 0 && test_bit(STRIPE_INSYNC, &sh->state)) { | |
2333 | md_done_sync(conf->mddev, STRIPE_SECTORS,1); | |
2334 | clear_bit(STRIPE_SYNCING, &sh->state); | |
2335 | } | |
2336 | ||
2337 | /* If the failed drives are just a ReadError, then we might need | |
2338 | * to progress the repair/check process | |
2339 | */ | |
2340 | if (failed <= 2 && ! conf->mddev->ro) | |
2341 | for (i=0; i<failed;i++) { | |
2342 | dev = &sh->dev[failed_num[i]]; | |
2343 | if (test_bit(R5_ReadError, &dev->flags) | |
2344 | && !test_bit(R5_LOCKED, &dev->flags) | |
2345 | && test_bit(R5_UPTODATE, &dev->flags) | |
2346 | ) { | |
2347 | if (!test_bit(R5_ReWrite, &dev->flags)) { | |
2348 | set_bit(R5_Wantwrite, &dev->flags); | |
2349 | set_bit(R5_ReWrite, &dev->flags); | |
2350 | set_bit(R5_LOCKED, &dev->flags); | |
2351 | } else { | |
2352 | /* let's read it back */ | |
2353 | set_bit(R5_Wantread, &dev->flags); | |
2354 | set_bit(R5_LOCKED, &dev->flags); | |
2355 | } | |
2356 | } | |
2357 | } | |
2358 | spin_unlock(&sh->lock); | |
2359 | ||
2360 | while ((bi=return_bi)) { | |
2361 | int bytes = bi->bi_size; | |
2362 | ||
2363 | return_bi = bi->bi_next; | |
2364 | bi->bi_next = NULL; | |
2365 | bi->bi_size = 0; | |
c2b00852 N |
2366 | bi->bi_end_io(bi, bytes, |
2367 | test_bit(BIO_UPTODATE, &bi->bi_flags) | |
2368 | ? 0 : -EIO); | |
16a53ecc N |
2369 | } |
2370 | for (i=disks; i-- ;) { | |
2371 | int rw; | |
2372 | struct bio *bi; | |
2373 | mdk_rdev_t *rdev; | |
2374 | if (test_and_clear_bit(R5_Wantwrite, &sh->dev[i].flags)) | |
802ba064 | 2375 | rw = WRITE; |
16a53ecc | 2376 | else if (test_and_clear_bit(R5_Wantread, &sh->dev[i].flags)) |
802ba064 | 2377 | rw = READ; |
16a53ecc N |
2378 | else |
2379 | continue; | |
2380 | ||
2381 | bi = &sh->dev[i].req; | |
2382 | ||
2383 | bi->bi_rw = rw; | |
802ba064 | 2384 | if (rw == WRITE) |
16a53ecc N |
2385 | bi->bi_end_io = raid5_end_write_request; |
2386 | else | |
2387 | bi->bi_end_io = raid5_end_read_request; | |
2388 | ||
2389 | rcu_read_lock(); | |
2390 | rdev = rcu_dereference(conf->disks[i].rdev); | |
2391 | if (rdev && test_bit(Faulty, &rdev->flags)) | |
2392 | rdev = NULL; | |
2393 | if (rdev) | |
2394 | atomic_inc(&rdev->nr_pending); | |
2395 | rcu_read_unlock(); | |
2396 | ||
2397 | if (rdev) { | |
2398 | if (syncing) | |
2399 | md_sync_acct(rdev->bdev, STRIPE_SECTORS); | |
2400 | ||
2401 | bi->bi_bdev = rdev->bdev; | |
2402 | PRINTK("for %llu schedule op %ld on disc %d\n", | |
2403 | (unsigned long long)sh->sector, bi->bi_rw, i); | |
2404 | atomic_inc(&sh->count); | |
2405 | bi->bi_sector = sh->sector + rdev->data_offset; | |
2406 | bi->bi_flags = 1 << BIO_UPTODATE; | |
2407 | bi->bi_vcnt = 1; | |
2408 | bi->bi_max_vecs = 1; | |
2409 | bi->bi_idx = 0; | |
2410 | bi->bi_io_vec = &sh->dev[i].vec; | |
2411 | bi->bi_io_vec[0].bv_len = STRIPE_SIZE; | |
2412 | bi->bi_io_vec[0].bv_offset = 0; | |
2413 | bi->bi_size = STRIPE_SIZE; | |
2414 | bi->bi_next = NULL; | |
2415 | if (rw == WRITE && | |
2416 | test_bit(R5_ReWrite, &sh->dev[i].flags)) | |
2417 | atomic_add(STRIPE_SECTORS, &rdev->corrected_errors); | |
2418 | generic_make_request(bi); | |
2419 | } else { | |
802ba064 | 2420 | if (rw == WRITE) |
16a53ecc N |
2421 | set_bit(STRIPE_DEGRADED, &sh->state); |
2422 | PRINTK("skip op %ld on disc %d for sector %llu\n", | |
2423 | bi->bi_rw, i, (unsigned long long)sh->sector); | |
2424 | clear_bit(R5_LOCKED, &sh->dev[i].flags); | |
2425 | set_bit(STRIPE_HANDLE, &sh->state); | |
2426 | } | |
2427 | } | |
2428 | } | |
2429 | ||
2430 | static void handle_stripe(struct stripe_head *sh, struct page *tmp_page) | |
2431 | { | |
2432 | if (sh->raid_conf->level == 6) | |
2433 | handle_stripe6(sh, tmp_page); | |
2434 | else | |
2435 | handle_stripe5(sh); | |
2436 | } | |
2437 | ||
2438 | ||
2439 | ||
2440 | static void raid5_activate_delayed(raid5_conf_t *conf) | |
2441 | { | |
2442 | if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD) { | |
2443 | while (!list_empty(&conf->delayed_list)) { | |
2444 | struct list_head *l = conf->delayed_list.next; | |
2445 | struct stripe_head *sh; | |
2446 | sh = list_entry(l, struct stripe_head, lru); | |
2447 | list_del_init(l); | |
2448 | clear_bit(STRIPE_DELAYED, &sh->state); | |
2449 | if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) | |
2450 | atomic_inc(&conf->preread_active_stripes); | |
2451 | list_add_tail(&sh->lru, &conf->handle_list); | |
2452 | } | |
2453 | } | |
2454 | } | |
2455 | ||
2456 | static void activate_bit_delay(raid5_conf_t *conf) | |
2457 | { | |
2458 | /* device_lock is held */ | |
2459 | struct list_head head; | |
2460 | list_add(&head, &conf->bitmap_list); | |
2461 | list_del_init(&conf->bitmap_list); | |
2462 | while (!list_empty(&head)) { | |
2463 | struct stripe_head *sh = list_entry(head.next, struct stripe_head, lru); | |
2464 | list_del_init(&sh->lru); | |
2465 | atomic_inc(&sh->count); | |
2466 | __release_stripe(conf, sh); | |
2467 | } | |
2468 | } | |
2469 | ||
2470 | static void unplug_slaves(mddev_t *mddev) | |
2471 | { | |
2472 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
2473 | int i; | |
2474 | ||
2475 | rcu_read_lock(); | |
2476 | for (i=0; i<mddev->raid_disks; i++) { | |
2477 | mdk_rdev_t *rdev = rcu_dereference(conf->disks[i].rdev); | |
2478 | if (rdev && !test_bit(Faulty, &rdev->flags) && atomic_read(&rdev->nr_pending)) { | |
2479 | request_queue_t *r_queue = bdev_get_queue(rdev->bdev); | |
2480 | ||
2481 | atomic_inc(&rdev->nr_pending); | |
2482 | rcu_read_unlock(); | |
2483 | ||
2484 | if (r_queue->unplug_fn) | |
2485 | r_queue->unplug_fn(r_queue); | |
2486 | ||
2487 | rdev_dec_pending(rdev, mddev); | |
2488 | rcu_read_lock(); | |
2489 | } | |
2490 | } | |
2491 | rcu_read_unlock(); | |
2492 | } | |
2493 | ||
2494 | static void raid5_unplug_device(request_queue_t *q) | |
2495 | { | |
2496 | mddev_t *mddev = q->queuedata; | |
2497 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
2498 | unsigned long flags; | |
2499 | ||
2500 | spin_lock_irqsave(&conf->device_lock, flags); | |
2501 | ||
2502 | if (blk_remove_plug(q)) { | |
2503 | conf->seq_flush++; | |
2504 | raid5_activate_delayed(conf); | |
72626685 | 2505 | } |
1da177e4 LT |
2506 | md_wakeup_thread(mddev->thread); |
2507 | ||
2508 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
2509 | ||
2510 | unplug_slaves(mddev); | |
2511 | } | |
2512 | ||
2513 | static int raid5_issue_flush(request_queue_t *q, struct gendisk *disk, | |
2514 | sector_t *error_sector) | |
2515 | { | |
2516 | mddev_t *mddev = q->queuedata; | |
2517 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
2518 | int i, ret = 0; | |
2519 | ||
2520 | rcu_read_lock(); | |
2521 | for (i=0; i<mddev->raid_disks && ret == 0; i++) { | |
d6065f7b | 2522 | mdk_rdev_t *rdev = rcu_dereference(conf->disks[i].rdev); |
b2d444d7 | 2523 | if (rdev && !test_bit(Faulty, &rdev->flags)) { |
1da177e4 LT |
2524 | struct block_device *bdev = rdev->bdev; |
2525 | request_queue_t *r_queue = bdev_get_queue(bdev); | |
2526 | ||
2527 | if (!r_queue->issue_flush_fn) | |
2528 | ret = -EOPNOTSUPP; | |
2529 | else { | |
2530 | atomic_inc(&rdev->nr_pending); | |
2531 | rcu_read_unlock(); | |
2532 | ret = r_queue->issue_flush_fn(r_queue, bdev->bd_disk, | |
2533 | error_sector); | |
2534 | rdev_dec_pending(rdev, mddev); | |
2535 | rcu_read_lock(); | |
2536 | } | |
2537 | } | |
2538 | } | |
2539 | rcu_read_unlock(); | |
2540 | return ret; | |
2541 | } | |
2542 | ||
f022b2fd N |
2543 | static int raid5_congested(void *data, int bits) |
2544 | { | |
2545 | mddev_t *mddev = data; | |
2546 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
2547 | ||
2548 | /* No difference between reads and writes. Just check | |
2549 | * how busy the stripe_cache is | |
2550 | */ | |
2551 | if (conf->inactive_blocked) | |
2552 | return 1; | |
2553 | if (conf->quiesce) | |
2554 | return 1; | |
2555 | if (list_empty_careful(&conf->inactive_list)) | |
2556 | return 1; | |
2557 | ||
2558 | return 0; | |
2559 | } | |
2560 | ||
23032a0e RBJ |
2561 | /* We want read requests to align with chunks where possible, |
2562 | * but write requests don't need to. | |
2563 | */ | |
2564 | static int raid5_mergeable_bvec(request_queue_t *q, struct bio *bio, struct bio_vec *biovec) | |
2565 | { | |
2566 | mddev_t *mddev = q->queuedata; | |
2567 | sector_t sector = bio->bi_sector + get_start_sect(bio->bi_bdev); | |
2568 | int max; | |
2569 | unsigned int chunk_sectors = mddev->chunk_size >> 9; | |
2570 | unsigned int bio_sectors = bio->bi_size >> 9; | |
2571 | ||
802ba064 | 2572 | if (bio_data_dir(bio) == WRITE) |
23032a0e RBJ |
2573 | return biovec->bv_len; /* always allow writes to be mergeable */ |
2574 | ||
2575 | max = (chunk_sectors - ((sector & (chunk_sectors - 1)) + bio_sectors)) << 9; | |
2576 | if (max < 0) max = 0; | |
2577 | if (max <= biovec->bv_len && bio_sectors == 0) | |
2578 | return biovec->bv_len; | |
2579 | else | |
2580 | return max; | |
2581 | } | |
2582 | ||
f679623f RBJ |
2583 | |
2584 | static int in_chunk_boundary(mddev_t *mddev, struct bio *bio) | |
2585 | { | |
2586 | sector_t sector = bio->bi_sector + get_start_sect(bio->bi_bdev); | |
2587 | unsigned int chunk_sectors = mddev->chunk_size >> 9; | |
2588 | unsigned int bio_sectors = bio->bi_size >> 9; | |
2589 | ||
2590 | return chunk_sectors >= | |
2591 | ((sector & (chunk_sectors - 1)) + bio_sectors); | |
2592 | } | |
2593 | ||
46031f9a RBJ |
2594 | /* |
2595 | * add bio to the retry LIFO ( in O(1) ... we are in interrupt ) | |
2596 | * later sampled by raid5d. | |
2597 | */ | |
2598 | static void add_bio_to_retry(struct bio *bi,raid5_conf_t *conf) | |
2599 | { | |
2600 | unsigned long flags; | |
2601 | ||
2602 | spin_lock_irqsave(&conf->device_lock, flags); | |
2603 | ||
2604 | bi->bi_next = conf->retry_read_aligned_list; | |
2605 | conf->retry_read_aligned_list = bi; | |
2606 | ||
2607 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
2608 | md_wakeup_thread(conf->mddev->thread); | |
2609 | } | |
2610 | ||
2611 | ||
2612 | static struct bio *remove_bio_from_retry(raid5_conf_t *conf) | |
2613 | { | |
2614 | struct bio *bi; | |
2615 | ||
2616 | bi = conf->retry_read_aligned; | |
2617 | if (bi) { | |
2618 | conf->retry_read_aligned = NULL; | |
2619 | return bi; | |
2620 | } | |
2621 | bi = conf->retry_read_aligned_list; | |
2622 | if(bi) { | |
2623 | conf->retry_read_aligned = bi->bi_next; | |
2624 | bi->bi_next = NULL; | |
2625 | bi->bi_phys_segments = 1; /* biased count of active stripes */ | |
2626 | bi->bi_hw_segments = 0; /* count of processed stripes */ | |
2627 | } | |
2628 | ||
2629 | return bi; | |
2630 | } | |
2631 | ||
2632 | ||
f679623f RBJ |
2633 | /* |
2634 | * The "raid5_align_endio" should check if the read succeeded and if it | |
2635 | * did, call bio_endio on the original bio (having bio_put the new bio | |
2636 | * first). | |
2637 | * If the read failed.. | |
2638 | */ | |
46031f9a | 2639 | static int raid5_align_endio(struct bio *bi, unsigned int bytes, int error) |
f679623f RBJ |
2640 | { |
2641 | struct bio* raid_bi = bi->bi_private; | |
46031f9a RBJ |
2642 | mddev_t *mddev; |
2643 | raid5_conf_t *conf; | |
2644 | int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags); | |
2645 | mdk_rdev_t *rdev; | |
2646 | ||
f679623f RBJ |
2647 | if (bi->bi_size) |
2648 | return 1; | |
2649 | bio_put(bi); | |
46031f9a RBJ |
2650 | |
2651 | mddev = raid_bi->bi_bdev->bd_disk->queue->queuedata; | |
2652 | conf = mddev_to_conf(mddev); | |
2653 | rdev = (void*)raid_bi->bi_next; | |
2654 | raid_bi->bi_next = NULL; | |
2655 | ||
2656 | rdev_dec_pending(rdev, conf->mddev); | |
2657 | ||
2658 | if (!error && uptodate) { | |
2659 | bio_endio(raid_bi, bytes, 0); | |
2660 | if (atomic_dec_and_test(&conf->active_aligned_reads)) | |
2661 | wake_up(&conf->wait_for_stripe); | |
2662 | return 0; | |
2663 | } | |
2664 | ||
2665 | ||
2666 | PRINTK("raid5_align_endio : io error...handing IO for a retry\n"); | |
2667 | ||
2668 | add_bio_to_retry(raid_bi, conf); | |
f679623f RBJ |
2669 | return 0; |
2670 | } | |
2671 | ||
2672 | static int chunk_aligned_read(request_queue_t *q, struct bio * raid_bio) | |
2673 | { | |
2674 | mddev_t *mddev = q->queuedata; | |
2675 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
2676 | const unsigned int raid_disks = conf->raid_disks; | |
46031f9a | 2677 | const unsigned int data_disks = raid_disks - conf->max_degraded; |
f679623f RBJ |
2678 | unsigned int dd_idx, pd_idx; |
2679 | struct bio* align_bi; | |
2680 | mdk_rdev_t *rdev; | |
2681 | ||
2682 | if (!in_chunk_boundary(mddev, raid_bio)) { | |
c20086de | 2683 | PRINTK("chunk_aligned_read : non aligned\n"); |
f679623f RBJ |
2684 | return 0; |
2685 | } | |
2686 | /* | |
2687 | * use bio_clone to make a copy of the bio | |
2688 | */ | |
2689 | align_bi = bio_clone(raid_bio, GFP_NOIO); | |
2690 | if (!align_bi) | |
2691 | return 0; | |
2692 | /* | |
2693 | * set bi_end_io to a new function, and set bi_private to the | |
2694 | * original bio. | |
2695 | */ | |
2696 | align_bi->bi_end_io = raid5_align_endio; | |
2697 | align_bi->bi_private = raid_bio; | |
2698 | /* | |
2699 | * compute position | |
2700 | */ | |
2701 | align_bi->bi_sector = raid5_compute_sector(raid_bio->bi_sector, | |
2702 | raid_disks, | |
2703 | data_disks, | |
2704 | &dd_idx, | |
2705 | &pd_idx, | |
2706 | conf); | |
2707 | ||
2708 | rcu_read_lock(); | |
2709 | rdev = rcu_dereference(conf->disks[dd_idx].rdev); | |
2710 | if (rdev && test_bit(In_sync, &rdev->flags)) { | |
f679623f RBJ |
2711 | atomic_inc(&rdev->nr_pending); |
2712 | rcu_read_unlock(); | |
46031f9a RBJ |
2713 | raid_bio->bi_next = (void*)rdev; |
2714 | align_bi->bi_bdev = rdev->bdev; | |
2715 | align_bi->bi_flags &= ~(1 << BIO_SEG_VALID); | |
2716 | align_bi->bi_sector += rdev->data_offset; | |
2717 | ||
2718 | spin_lock_irq(&conf->device_lock); | |
2719 | wait_event_lock_irq(conf->wait_for_stripe, | |
2720 | conf->quiesce == 0, | |
2721 | conf->device_lock, /* nothing */); | |
2722 | atomic_inc(&conf->active_aligned_reads); | |
2723 | spin_unlock_irq(&conf->device_lock); | |
2724 | ||
f679623f RBJ |
2725 | generic_make_request(align_bi); |
2726 | return 1; | |
2727 | } else { | |
2728 | rcu_read_unlock(); | |
46031f9a | 2729 | bio_put(align_bi); |
f679623f RBJ |
2730 | return 0; |
2731 | } | |
2732 | } | |
2733 | ||
2734 | ||
7ecaa1e6 | 2735 | static int make_request(request_queue_t *q, struct bio * bi) |
1da177e4 LT |
2736 | { |
2737 | mddev_t *mddev = q->queuedata; | |
2738 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
1da177e4 LT |
2739 | unsigned int dd_idx, pd_idx; |
2740 | sector_t new_sector; | |
2741 | sector_t logical_sector, last_sector; | |
2742 | struct stripe_head *sh; | |
a362357b | 2743 | const int rw = bio_data_dir(bi); |
f6344757 | 2744 | int remaining; |
1da177e4 | 2745 | |
e5dcdd80 N |
2746 | if (unlikely(bio_barrier(bi))) { |
2747 | bio_endio(bi, bi->bi_size, -EOPNOTSUPP); | |
2748 | return 0; | |
2749 | } | |
2750 | ||
3d310eb7 | 2751 | md_write_start(mddev, bi); |
06d91a5f | 2752 | |
a362357b JA |
2753 | disk_stat_inc(mddev->gendisk, ios[rw]); |
2754 | disk_stat_add(mddev->gendisk, sectors[rw], bio_sectors(bi)); | |
1da177e4 | 2755 | |
802ba064 | 2756 | if (rw == READ && |
52488615 RBJ |
2757 | mddev->reshape_position == MaxSector && |
2758 | chunk_aligned_read(q,bi)) | |
2759 | return 0; | |
2760 | ||
1da177e4 LT |
2761 | logical_sector = bi->bi_sector & ~((sector_t)STRIPE_SECTORS-1); |
2762 | last_sector = bi->bi_sector + (bi->bi_size>>9); | |
2763 | bi->bi_next = NULL; | |
2764 | bi->bi_phys_segments = 1; /* over-loaded to count active stripes */ | |
06d91a5f | 2765 | |
1da177e4 LT |
2766 | for (;logical_sector < last_sector; logical_sector += STRIPE_SECTORS) { |
2767 | DEFINE_WAIT(w); | |
16a53ecc | 2768 | int disks, data_disks; |
b578d55f | 2769 | |
7ecaa1e6 | 2770 | retry: |
b578d55f | 2771 | prepare_to_wait(&conf->wait_for_overlap, &w, TASK_UNINTERRUPTIBLE); |
7ecaa1e6 N |
2772 | if (likely(conf->expand_progress == MaxSector)) |
2773 | disks = conf->raid_disks; | |
2774 | else { | |
df8e7f76 N |
2775 | /* spinlock is needed as expand_progress may be |
2776 | * 64bit on a 32bit platform, and so it might be | |
2777 | * possible to see a half-updated value | |
2778 | * Ofcourse expand_progress could change after | |
2779 | * the lock is dropped, so once we get a reference | |
2780 | * to the stripe that we think it is, we will have | |
2781 | * to check again. | |
2782 | */ | |
7ecaa1e6 N |
2783 | spin_lock_irq(&conf->device_lock); |
2784 | disks = conf->raid_disks; | |
2785 | if (logical_sector >= conf->expand_progress) | |
2786 | disks = conf->previous_raid_disks; | |
b578d55f N |
2787 | else { |
2788 | if (logical_sector >= conf->expand_lo) { | |
2789 | spin_unlock_irq(&conf->device_lock); | |
2790 | schedule(); | |
2791 | goto retry; | |
2792 | } | |
2793 | } | |
7ecaa1e6 N |
2794 | spin_unlock_irq(&conf->device_lock); |
2795 | } | |
16a53ecc N |
2796 | data_disks = disks - conf->max_degraded; |
2797 | ||
2798 | new_sector = raid5_compute_sector(logical_sector, disks, data_disks, | |
7ecaa1e6 | 2799 | &dd_idx, &pd_idx, conf); |
1da177e4 LT |
2800 | PRINTK("raid5: make_request, sector %llu logical %llu\n", |
2801 | (unsigned long long)new_sector, | |
2802 | (unsigned long long)logical_sector); | |
2803 | ||
7ecaa1e6 | 2804 | sh = get_active_stripe(conf, new_sector, disks, pd_idx, (bi->bi_rw&RWA_MASK)); |
1da177e4 | 2805 | if (sh) { |
7ecaa1e6 N |
2806 | if (unlikely(conf->expand_progress != MaxSector)) { |
2807 | /* expansion might have moved on while waiting for a | |
df8e7f76 N |
2808 | * stripe, so we must do the range check again. |
2809 | * Expansion could still move past after this | |
2810 | * test, but as we are holding a reference to | |
2811 | * 'sh', we know that if that happens, | |
2812 | * STRIPE_EXPANDING will get set and the expansion | |
2813 | * won't proceed until we finish with the stripe. | |
7ecaa1e6 N |
2814 | */ |
2815 | int must_retry = 0; | |
2816 | spin_lock_irq(&conf->device_lock); | |
2817 | if (logical_sector < conf->expand_progress && | |
2818 | disks == conf->previous_raid_disks) | |
2819 | /* mismatch, need to try again */ | |
2820 | must_retry = 1; | |
2821 | spin_unlock_irq(&conf->device_lock); | |
2822 | if (must_retry) { | |
2823 | release_stripe(sh); | |
2824 | goto retry; | |
2825 | } | |
2826 | } | |
e464eafd N |
2827 | /* FIXME what if we get a false positive because these |
2828 | * are being updated. | |
2829 | */ | |
2830 | if (logical_sector >= mddev->suspend_lo && | |
2831 | logical_sector < mddev->suspend_hi) { | |
2832 | release_stripe(sh); | |
2833 | schedule(); | |
2834 | goto retry; | |
2835 | } | |
7ecaa1e6 N |
2836 | |
2837 | if (test_bit(STRIPE_EXPANDING, &sh->state) || | |
2838 | !add_stripe_bio(sh, bi, dd_idx, (bi->bi_rw&RW_MASK))) { | |
2839 | /* Stripe is busy expanding or | |
2840 | * add failed due to overlap. Flush everything | |
1da177e4 LT |
2841 | * and wait a while |
2842 | */ | |
2843 | raid5_unplug_device(mddev->queue); | |
2844 | release_stripe(sh); | |
2845 | schedule(); | |
2846 | goto retry; | |
2847 | } | |
2848 | finish_wait(&conf->wait_for_overlap, &w); | |
16a53ecc | 2849 | handle_stripe(sh, NULL); |
1da177e4 | 2850 | release_stripe(sh); |
1da177e4 LT |
2851 | } else { |
2852 | /* cannot get stripe for read-ahead, just give-up */ | |
2853 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
2854 | finish_wait(&conf->wait_for_overlap, &w); | |
2855 | break; | |
2856 | } | |
2857 | ||
2858 | } | |
2859 | spin_lock_irq(&conf->device_lock); | |
f6344757 N |
2860 | remaining = --bi->bi_phys_segments; |
2861 | spin_unlock_irq(&conf->device_lock); | |
2862 | if (remaining == 0) { | |
1da177e4 LT |
2863 | int bytes = bi->bi_size; |
2864 | ||
16a53ecc | 2865 | if ( rw == WRITE ) |
1da177e4 LT |
2866 | md_write_end(mddev); |
2867 | bi->bi_size = 0; | |
c2b00852 N |
2868 | bi->bi_end_io(bi, bytes, |
2869 | test_bit(BIO_UPTODATE, &bi->bi_flags) | |
2870 | ? 0 : -EIO); | |
1da177e4 | 2871 | } |
1da177e4 LT |
2872 | return 0; |
2873 | } | |
2874 | ||
52c03291 | 2875 | static sector_t reshape_request(mddev_t *mddev, sector_t sector_nr, int *skipped) |
1da177e4 | 2876 | { |
52c03291 N |
2877 | /* reshaping is quite different to recovery/resync so it is |
2878 | * handled quite separately ... here. | |
2879 | * | |
2880 | * On each call to sync_request, we gather one chunk worth of | |
2881 | * destination stripes and flag them as expanding. | |
2882 | * Then we find all the source stripes and request reads. | |
2883 | * As the reads complete, handle_stripe will copy the data | |
2884 | * into the destination stripe and release that stripe. | |
2885 | */ | |
1da177e4 LT |
2886 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; |
2887 | struct stripe_head *sh; | |
ccfcc3c1 N |
2888 | int pd_idx; |
2889 | sector_t first_sector, last_sector; | |
52c03291 N |
2890 | int raid_disks; |
2891 | int data_disks; | |
2892 | int i; | |
2893 | int dd_idx; | |
2894 | sector_t writepos, safepos, gap; | |
2895 | ||
2896 | if (sector_nr == 0 && | |
2897 | conf->expand_progress != 0) { | |
2898 | /* restarting in the middle, skip the initial sectors */ | |
2899 | sector_nr = conf->expand_progress; | |
2900 | sector_div(sector_nr, conf->raid_disks-1); | |
2901 | *skipped = 1; | |
2902 | return sector_nr; | |
2903 | } | |
2904 | ||
2905 | /* we update the metadata when there is more than 3Meg | |
2906 | * in the block range (that is rather arbitrary, should | |
2907 | * probably be time based) or when the data about to be | |
2908 | * copied would over-write the source of the data at | |
2909 | * the front of the range. | |
2910 | * i.e. one new_stripe forward from expand_progress new_maps | |
2911 | * to after where expand_lo old_maps to | |
2912 | */ | |
2913 | writepos = conf->expand_progress + | |
2914 | conf->chunk_size/512*(conf->raid_disks-1); | |
2915 | sector_div(writepos, conf->raid_disks-1); | |
2916 | safepos = conf->expand_lo; | |
2917 | sector_div(safepos, conf->previous_raid_disks-1); | |
2918 | gap = conf->expand_progress - conf->expand_lo; | |
2919 | ||
2920 | if (writepos >= safepos || | |
2921 | gap > (conf->raid_disks-1)*3000*2 /*3Meg*/) { | |
2922 | /* Cannot proceed until we've updated the superblock... */ | |
2923 | wait_event(conf->wait_for_overlap, | |
2924 | atomic_read(&conf->reshape_stripes)==0); | |
2925 | mddev->reshape_position = conf->expand_progress; | |
850b2b42 | 2926 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
52c03291 | 2927 | md_wakeup_thread(mddev->thread); |
850b2b42 | 2928 | wait_event(mddev->sb_wait, mddev->flags == 0 || |
52c03291 N |
2929 | kthread_should_stop()); |
2930 | spin_lock_irq(&conf->device_lock); | |
2931 | conf->expand_lo = mddev->reshape_position; | |
2932 | spin_unlock_irq(&conf->device_lock); | |
2933 | wake_up(&conf->wait_for_overlap); | |
2934 | } | |
2935 | ||
2936 | for (i=0; i < conf->chunk_size/512; i+= STRIPE_SECTORS) { | |
2937 | int j; | |
2938 | int skipped = 0; | |
2939 | pd_idx = stripe_to_pdidx(sector_nr+i, conf, conf->raid_disks); | |
2940 | sh = get_active_stripe(conf, sector_nr+i, | |
2941 | conf->raid_disks, pd_idx, 0); | |
2942 | set_bit(STRIPE_EXPANDING, &sh->state); | |
2943 | atomic_inc(&conf->reshape_stripes); | |
2944 | /* If any of this stripe is beyond the end of the old | |
2945 | * array, then we need to zero those blocks | |
2946 | */ | |
2947 | for (j=sh->disks; j--;) { | |
2948 | sector_t s; | |
2949 | if (j == sh->pd_idx) | |
2950 | continue; | |
2951 | s = compute_blocknr(sh, j); | |
2952 | if (s < (mddev->array_size<<1)) { | |
2953 | skipped = 1; | |
2954 | continue; | |
2955 | } | |
2956 | memset(page_address(sh->dev[j].page), 0, STRIPE_SIZE); | |
2957 | set_bit(R5_Expanded, &sh->dev[j].flags); | |
2958 | set_bit(R5_UPTODATE, &sh->dev[j].flags); | |
2959 | } | |
2960 | if (!skipped) { | |
2961 | set_bit(STRIPE_EXPAND_READY, &sh->state); | |
2962 | set_bit(STRIPE_HANDLE, &sh->state); | |
2963 | } | |
2964 | release_stripe(sh); | |
2965 | } | |
2966 | spin_lock_irq(&conf->device_lock); | |
2967 | conf->expand_progress = (sector_nr + i)*(conf->raid_disks-1); | |
2968 | spin_unlock_irq(&conf->device_lock); | |
2969 | /* Ok, those stripe are ready. We can start scheduling | |
2970 | * reads on the source stripes. | |
2971 | * The source stripes are determined by mapping the first and last | |
2972 | * block on the destination stripes. | |
2973 | */ | |
2974 | raid_disks = conf->previous_raid_disks; | |
2975 | data_disks = raid_disks - 1; | |
2976 | first_sector = | |
2977 | raid5_compute_sector(sector_nr*(conf->raid_disks-1), | |
2978 | raid_disks, data_disks, | |
2979 | &dd_idx, &pd_idx, conf); | |
2980 | last_sector = | |
2981 | raid5_compute_sector((sector_nr+conf->chunk_size/512) | |
2982 | *(conf->raid_disks-1) -1, | |
2983 | raid_disks, data_disks, | |
2984 | &dd_idx, &pd_idx, conf); | |
2985 | if (last_sector >= (mddev->size<<1)) | |
2986 | last_sector = (mddev->size<<1)-1; | |
2987 | while (first_sector <= last_sector) { | |
2988 | pd_idx = stripe_to_pdidx(first_sector, conf, conf->previous_raid_disks); | |
2989 | sh = get_active_stripe(conf, first_sector, | |
2990 | conf->previous_raid_disks, pd_idx, 0); | |
2991 | set_bit(STRIPE_EXPAND_SOURCE, &sh->state); | |
2992 | set_bit(STRIPE_HANDLE, &sh->state); | |
2993 | release_stripe(sh); | |
2994 | first_sector += STRIPE_SECTORS; | |
2995 | } | |
2996 | return conf->chunk_size>>9; | |
2997 | } | |
2998 | ||
2999 | /* FIXME go_faster isn't used */ | |
3000 | static inline sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, int go_faster) | |
3001 | { | |
3002 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; | |
3003 | struct stripe_head *sh; | |
3004 | int pd_idx; | |
1da177e4 | 3005 | int raid_disks = conf->raid_disks; |
72626685 N |
3006 | sector_t max_sector = mddev->size << 1; |
3007 | int sync_blocks; | |
16a53ecc N |
3008 | int still_degraded = 0; |
3009 | int i; | |
1da177e4 | 3010 | |
72626685 | 3011 | if (sector_nr >= max_sector) { |
1da177e4 LT |
3012 | /* just being told to finish up .. nothing much to do */ |
3013 | unplug_slaves(mddev); | |
29269553 N |
3014 | if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) { |
3015 | end_reshape(conf); | |
3016 | return 0; | |
3017 | } | |
72626685 N |
3018 | |
3019 | if (mddev->curr_resync < max_sector) /* aborted */ | |
3020 | bitmap_end_sync(mddev->bitmap, mddev->curr_resync, | |
3021 | &sync_blocks, 1); | |
16a53ecc | 3022 | else /* completed sync */ |
72626685 N |
3023 | conf->fullsync = 0; |
3024 | bitmap_close_sync(mddev->bitmap); | |
3025 | ||
1da177e4 LT |
3026 | return 0; |
3027 | } | |
ccfcc3c1 | 3028 | |
52c03291 N |
3029 | if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) |
3030 | return reshape_request(mddev, sector_nr, skipped); | |
f6705578 | 3031 | |
16a53ecc | 3032 | /* if there is too many failed drives and we are trying |
1da177e4 LT |
3033 | * to resync, then assert that we are finished, because there is |
3034 | * nothing we can do. | |
3035 | */ | |
3285edf1 | 3036 | if (mddev->degraded >= conf->max_degraded && |
16a53ecc | 3037 | test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) { |
57afd89f N |
3038 | sector_t rv = (mddev->size << 1) - sector_nr; |
3039 | *skipped = 1; | |
1da177e4 LT |
3040 | return rv; |
3041 | } | |
72626685 | 3042 | if (!bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, 1) && |
3855ad9f | 3043 | !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) && |
72626685 N |
3044 | !conf->fullsync && sync_blocks >= STRIPE_SECTORS) { |
3045 | /* we can skip this block, and probably more */ | |
3046 | sync_blocks /= STRIPE_SECTORS; | |
3047 | *skipped = 1; | |
3048 | return sync_blocks * STRIPE_SECTORS; /* keep things rounded to whole stripes */ | |
3049 | } | |
1da177e4 | 3050 | |
ccfcc3c1 | 3051 | pd_idx = stripe_to_pdidx(sector_nr, conf, raid_disks); |
7ecaa1e6 | 3052 | sh = get_active_stripe(conf, sector_nr, raid_disks, pd_idx, 1); |
1da177e4 | 3053 | if (sh == NULL) { |
7ecaa1e6 | 3054 | sh = get_active_stripe(conf, sector_nr, raid_disks, pd_idx, 0); |
1da177e4 | 3055 | /* make sure we don't swamp the stripe cache if someone else |
16a53ecc | 3056 | * is trying to get access |
1da177e4 | 3057 | */ |
66c006a5 | 3058 | schedule_timeout_uninterruptible(1); |
1da177e4 | 3059 | } |
16a53ecc N |
3060 | /* Need to check if array will still be degraded after recovery/resync |
3061 | * We don't need to check the 'failed' flag as when that gets set, | |
3062 | * recovery aborts. | |
3063 | */ | |
3064 | for (i=0; i<mddev->raid_disks; i++) | |
3065 | if (conf->disks[i].rdev == NULL) | |
3066 | still_degraded = 1; | |
3067 | ||
3068 | bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, still_degraded); | |
3069 | ||
3070 | spin_lock(&sh->lock); | |
1da177e4 LT |
3071 | set_bit(STRIPE_SYNCING, &sh->state); |
3072 | clear_bit(STRIPE_INSYNC, &sh->state); | |
3073 | spin_unlock(&sh->lock); | |
3074 | ||
16a53ecc | 3075 | handle_stripe(sh, NULL); |
1da177e4 LT |
3076 | release_stripe(sh); |
3077 | ||
3078 | return STRIPE_SECTORS; | |
3079 | } | |
3080 | ||
46031f9a RBJ |
3081 | static int retry_aligned_read(raid5_conf_t *conf, struct bio *raid_bio) |
3082 | { | |
3083 | /* We may not be able to submit a whole bio at once as there | |
3084 | * may not be enough stripe_heads available. | |
3085 | * We cannot pre-allocate enough stripe_heads as we may need | |
3086 | * more than exist in the cache (if we allow ever large chunks). | |
3087 | * So we do one stripe head at a time and record in | |
3088 | * ->bi_hw_segments how many have been done. | |
3089 | * | |
3090 | * We *know* that this entire raid_bio is in one chunk, so | |
3091 | * it will be only one 'dd_idx' and only need one call to raid5_compute_sector. | |
3092 | */ | |
3093 | struct stripe_head *sh; | |
3094 | int dd_idx, pd_idx; | |
3095 | sector_t sector, logical_sector, last_sector; | |
3096 | int scnt = 0; | |
3097 | int remaining; | |
3098 | int handled = 0; | |
3099 | ||
3100 | logical_sector = raid_bio->bi_sector & ~((sector_t)STRIPE_SECTORS-1); | |
3101 | sector = raid5_compute_sector( logical_sector, | |
3102 | conf->raid_disks, | |
3103 | conf->raid_disks - conf->max_degraded, | |
3104 | &dd_idx, | |
3105 | &pd_idx, | |
3106 | conf); | |
3107 | last_sector = raid_bio->bi_sector + (raid_bio->bi_size>>9); | |
3108 | ||
3109 | for (; logical_sector < last_sector; | |
3110 | logical_sector += STRIPE_SECTORS, scnt++) { | |
3111 | ||
3112 | if (scnt < raid_bio->bi_hw_segments) | |
3113 | /* already done this stripe */ | |
3114 | continue; | |
3115 | ||
3116 | sh = get_active_stripe(conf, sector, conf->raid_disks, pd_idx, 1); | |
3117 | ||
3118 | if (!sh) { | |
3119 | /* failed to get a stripe - must wait */ | |
3120 | raid_bio->bi_hw_segments = scnt; | |
3121 | conf->retry_read_aligned = raid_bio; | |
3122 | return handled; | |
3123 | } | |
3124 | ||
3125 | set_bit(R5_ReadError, &sh->dev[dd_idx].flags); | |
3126 | add_stripe_bio(sh, raid_bio, dd_idx, 0); | |
3127 | handle_stripe(sh, NULL); | |
3128 | release_stripe(sh); | |
3129 | handled++; | |
3130 | } | |
3131 | spin_lock_irq(&conf->device_lock); | |
3132 | remaining = --raid_bio->bi_phys_segments; | |
3133 | spin_unlock_irq(&conf->device_lock); | |
3134 | if (remaining == 0) { | |
3135 | int bytes = raid_bio->bi_size; | |
3136 | ||
3137 | raid_bio->bi_size = 0; | |
c2b00852 N |
3138 | raid_bio->bi_end_io(raid_bio, bytes, |
3139 | test_bit(BIO_UPTODATE, &raid_bio->bi_flags) | |
3140 | ? 0 : -EIO); | |
46031f9a RBJ |
3141 | } |
3142 | if (atomic_dec_and_test(&conf->active_aligned_reads)) | |
3143 | wake_up(&conf->wait_for_stripe); | |
3144 | return handled; | |
3145 | } | |
3146 | ||
3147 | ||
3148 | ||
1da177e4 LT |
3149 | /* |
3150 | * This is our raid5 kernel thread. | |
3151 | * | |
3152 | * We scan the hash table for stripes which can be handled now. | |
3153 | * During the scan, completed stripes are saved for us by the interrupt | |
3154 | * handler, so that they will not have to wait for our next wakeup. | |
3155 | */ | |
3156 | static void raid5d (mddev_t *mddev) | |
3157 | { | |
3158 | struct stripe_head *sh; | |
3159 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
3160 | int handled; | |
3161 | ||
3162 | PRINTK("+++ raid5d active\n"); | |
3163 | ||
3164 | md_check_recovery(mddev); | |
1da177e4 LT |
3165 | |
3166 | handled = 0; | |
3167 | spin_lock_irq(&conf->device_lock); | |
3168 | while (1) { | |
3169 | struct list_head *first; | |
46031f9a | 3170 | struct bio *bio; |
1da177e4 | 3171 | |
ae3c20cc | 3172 | if (conf->seq_flush != conf->seq_write) { |
72626685 | 3173 | int seq = conf->seq_flush; |
700e432d | 3174 | spin_unlock_irq(&conf->device_lock); |
72626685 | 3175 | bitmap_unplug(mddev->bitmap); |
700e432d | 3176 | spin_lock_irq(&conf->device_lock); |
72626685 N |
3177 | conf->seq_write = seq; |
3178 | activate_bit_delay(conf); | |
3179 | } | |
3180 | ||
1da177e4 LT |
3181 | if (list_empty(&conf->handle_list) && |
3182 | atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD && | |
3183 | !blk_queue_plugged(mddev->queue) && | |
3184 | !list_empty(&conf->delayed_list)) | |
3185 | raid5_activate_delayed(conf); | |
3186 | ||
46031f9a RBJ |
3187 | while ((bio = remove_bio_from_retry(conf))) { |
3188 | int ok; | |
3189 | spin_unlock_irq(&conf->device_lock); | |
3190 | ok = retry_aligned_read(conf, bio); | |
3191 | spin_lock_irq(&conf->device_lock); | |
3192 | if (!ok) | |
3193 | break; | |
3194 | handled++; | |
3195 | } | |
3196 | ||
1da177e4 LT |
3197 | if (list_empty(&conf->handle_list)) |
3198 | break; | |
3199 | ||
3200 | first = conf->handle_list.next; | |
3201 | sh = list_entry(first, struct stripe_head, lru); | |
3202 | ||
3203 | list_del_init(first); | |
3204 | atomic_inc(&sh->count); | |
78bafebd | 3205 | BUG_ON(atomic_read(&sh->count)!= 1); |
1da177e4 LT |
3206 | spin_unlock_irq(&conf->device_lock); |
3207 | ||
3208 | handled++; | |
16a53ecc | 3209 | handle_stripe(sh, conf->spare_page); |
1da177e4 LT |
3210 | release_stripe(sh); |
3211 | ||
3212 | spin_lock_irq(&conf->device_lock); | |
3213 | } | |
3214 | PRINTK("%d stripes handled\n", handled); | |
3215 | ||
3216 | spin_unlock_irq(&conf->device_lock); | |
3217 | ||
3218 | unplug_slaves(mddev); | |
3219 | ||
3220 | PRINTK("--- raid5d inactive\n"); | |
3221 | } | |
3222 | ||
3f294f4f | 3223 | static ssize_t |
007583c9 | 3224 | raid5_show_stripe_cache_size(mddev_t *mddev, char *page) |
3f294f4f | 3225 | { |
007583c9 | 3226 | raid5_conf_t *conf = mddev_to_conf(mddev); |
96de1e66 N |
3227 | if (conf) |
3228 | return sprintf(page, "%d\n", conf->max_nr_stripes); | |
3229 | else | |
3230 | return 0; | |
3f294f4f N |
3231 | } |
3232 | ||
3233 | static ssize_t | |
007583c9 | 3234 | raid5_store_stripe_cache_size(mddev_t *mddev, const char *page, size_t len) |
3f294f4f | 3235 | { |
007583c9 | 3236 | raid5_conf_t *conf = mddev_to_conf(mddev); |
3f294f4f N |
3237 | char *end; |
3238 | int new; | |
3239 | if (len >= PAGE_SIZE) | |
3240 | return -EINVAL; | |
96de1e66 N |
3241 | if (!conf) |
3242 | return -ENODEV; | |
3f294f4f N |
3243 | |
3244 | new = simple_strtoul(page, &end, 10); | |
3245 | if (!*page || (*end && *end != '\n') ) | |
3246 | return -EINVAL; | |
3247 | if (new <= 16 || new > 32768) | |
3248 | return -EINVAL; | |
3249 | while (new < conf->max_nr_stripes) { | |
3250 | if (drop_one_stripe(conf)) | |
3251 | conf->max_nr_stripes--; | |
3252 | else | |
3253 | break; | |
3254 | } | |
2a2275d6 | 3255 | md_allow_write(mddev); |
3f294f4f N |
3256 | while (new > conf->max_nr_stripes) { |
3257 | if (grow_one_stripe(conf)) | |
3258 | conf->max_nr_stripes++; | |
3259 | else break; | |
3260 | } | |
3261 | return len; | |
3262 | } | |
007583c9 | 3263 | |
96de1e66 N |
3264 | static struct md_sysfs_entry |
3265 | raid5_stripecache_size = __ATTR(stripe_cache_size, S_IRUGO | S_IWUSR, | |
3266 | raid5_show_stripe_cache_size, | |
3267 | raid5_store_stripe_cache_size); | |
3f294f4f N |
3268 | |
3269 | static ssize_t | |
96de1e66 | 3270 | stripe_cache_active_show(mddev_t *mddev, char *page) |
3f294f4f | 3271 | { |
007583c9 | 3272 | raid5_conf_t *conf = mddev_to_conf(mddev); |
96de1e66 N |
3273 | if (conf) |
3274 | return sprintf(page, "%d\n", atomic_read(&conf->active_stripes)); | |
3275 | else | |
3276 | return 0; | |
3f294f4f N |
3277 | } |
3278 | ||
96de1e66 N |
3279 | static struct md_sysfs_entry |
3280 | raid5_stripecache_active = __ATTR_RO(stripe_cache_active); | |
3f294f4f | 3281 | |
007583c9 | 3282 | static struct attribute *raid5_attrs[] = { |
3f294f4f N |
3283 | &raid5_stripecache_size.attr, |
3284 | &raid5_stripecache_active.attr, | |
3285 | NULL, | |
3286 | }; | |
007583c9 N |
3287 | static struct attribute_group raid5_attrs_group = { |
3288 | .name = NULL, | |
3289 | .attrs = raid5_attrs, | |
3f294f4f N |
3290 | }; |
3291 | ||
72626685 | 3292 | static int run(mddev_t *mddev) |
1da177e4 LT |
3293 | { |
3294 | raid5_conf_t *conf; | |
3295 | int raid_disk, memory; | |
3296 | mdk_rdev_t *rdev; | |
3297 | struct disk_info *disk; | |
3298 | struct list_head *tmp; | |
02c2de8c | 3299 | int working_disks = 0; |
1da177e4 | 3300 | |
16a53ecc N |
3301 | if (mddev->level != 5 && mddev->level != 4 && mddev->level != 6) { |
3302 | printk(KERN_ERR "raid5: %s: raid level not set to 4/5/6 (%d)\n", | |
14f8d26b | 3303 | mdname(mddev), mddev->level); |
1da177e4 LT |
3304 | return -EIO; |
3305 | } | |
3306 | ||
f6705578 N |
3307 | if (mddev->reshape_position != MaxSector) { |
3308 | /* Check that we can continue the reshape. | |
3309 | * Currently only disks can change, it must | |
3310 | * increase, and we must be past the point where | |
3311 | * a stripe over-writes itself | |
3312 | */ | |
3313 | sector_t here_new, here_old; | |
3314 | int old_disks; | |
3315 | ||
3316 | if (mddev->new_level != mddev->level || | |
3317 | mddev->new_layout != mddev->layout || | |
3318 | mddev->new_chunk != mddev->chunk_size) { | |
3319 | printk(KERN_ERR "raid5: %s: unsupported reshape required - aborting.\n", | |
3320 | mdname(mddev)); | |
3321 | return -EINVAL; | |
3322 | } | |
3323 | if (mddev->delta_disks <= 0) { | |
3324 | printk(KERN_ERR "raid5: %s: unsupported reshape (reduce disks) required - aborting.\n", | |
3325 | mdname(mddev)); | |
3326 | return -EINVAL; | |
3327 | } | |
3328 | old_disks = mddev->raid_disks - mddev->delta_disks; | |
3329 | /* reshape_position must be on a new-stripe boundary, and one | |
3330 | * further up in new geometry must map after here in old geometry. | |
3331 | */ | |
3332 | here_new = mddev->reshape_position; | |
3333 | if (sector_div(here_new, (mddev->chunk_size>>9)*(mddev->raid_disks-1))) { | |
3334 | printk(KERN_ERR "raid5: reshape_position not on a stripe boundary\n"); | |
3335 | return -EINVAL; | |
3336 | } | |
3337 | /* here_new is the stripe we will write to */ | |
3338 | here_old = mddev->reshape_position; | |
3339 | sector_div(here_old, (mddev->chunk_size>>9)*(old_disks-1)); | |
3340 | /* here_old is the first stripe that we might need to read from */ | |
3341 | if (here_new >= here_old) { | |
3342 | /* Reading from the same stripe as writing to - bad */ | |
3343 | printk(KERN_ERR "raid5: reshape_position too early for auto-recovery - aborting.\n"); | |
3344 | return -EINVAL; | |
3345 | } | |
3346 | printk(KERN_INFO "raid5: reshape will continue\n"); | |
3347 | /* OK, we should be able to continue; */ | |
3348 | } | |
3349 | ||
3350 | ||
b55e6bfc | 3351 | mddev->private = kzalloc(sizeof (raid5_conf_t), GFP_KERNEL); |
1da177e4 LT |
3352 | if ((conf = mddev->private) == NULL) |
3353 | goto abort; | |
f6705578 N |
3354 | if (mddev->reshape_position == MaxSector) { |
3355 | conf->previous_raid_disks = conf->raid_disks = mddev->raid_disks; | |
3356 | } else { | |
3357 | conf->raid_disks = mddev->raid_disks; | |
3358 | conf->previous_raid_disks = mddev->raid_disks - mddev->delta_disks; | |
3359 | } | |
3360 | ||
3361 | conf->disks = kzalloc(conf->raid_disks * sizeof(struct disk_info), | |
b55e6bfc N |
3362 | GFP_KERNEL); |
3363 | if (!conf->disks) | |
3364 | goto abort; | |
9ffae0cf | 3365 | |
1da177e4 LT |
3366 | conf->mddev = mddev; |
3367 | ||
fccddba0 | 3368 | if ((conf->stripe_hashtbl = kzalloc(PAGE_SIZE, GFP_KERNEL)) == NULL) |
1da177e4 | 3369 | goto abort; |
1da177e4 | 3370 | |
16a53ecc N |
3371 | if (mddev->level == 6) { |
3372 | conf->spare_page = alloc_page(GFP_KERNEL); | |
3373 | if (!conf->spare_page) | |
3374 | goto abort; | |
3375 | } | |
1da177e4 LT |
3376 | spin_lock_init(&conf->device_lock); |
3377 | init_waitqueue_head(&conf->wait_for_stripe); | |
3378 | init_waitqueue_head(&conf->wait_for_overlap); | |
3379 | INIT_LIST_HEAD(&conf->handle_list); | |
3380 | INIT_LIST_HEAD(&conf->delayed_list); | |
72626685 | 3381 | INIT_LIST_HEAD(&conf->bitmap_list); |
1da177e4 LT |
3382 | INIT_LIST_HEAD(&conf->inactive_list); |
3383 | atomic_set(&conf->active_stripes, 0); | |
3384 | atomic_set(&conf->preread_active_stripes, 0); | |
46031f9a | 3385 | atomic_set(&conf->active_aligned_reads, 0); |
1da177e4 | 3386 | |
1da177e4 LT |
3387 | PRINTK("raid5: run(%s) called.\n", mdname(mddev)); |
3388 | ||
3389 | ITERATE_RDEV(mddev,rdev,tmp) { | |
3390 | raid_disk = rdev->raid_disk; | |
f6705578 | 3391 | if (raid_disk >= conf->raid_disks |
1da177e4 LT |
3392 | || raid_disk < 0) |
3393 | continue; | |
3394 | disk = conf->disks + raid_disk; | |
3395 | ||
3396 | disk->rdev = rdev; | |
3397 | ||
b2d444d7 | 3398 | if (test_bit(In_sync, &rdev->flags)) { |
1da177e4 LT |
3399 | char b[BDEVNAME_SIZE]; |
3400 | printk(KERN_INFO "raid5: device %s operational as raid" | |
3401 | " disk %d\n", bdevname(rdev->bdev,b), | |
3402 | raid_disk); | |
02c2de8c | 3403 | working_disks++; |
1da177e4 LT |
3404 | } |
3405 | } | |
3406 | ||
1da177e4 | 3407 | /* |
16a53ecc | 3408 | * 0 for a fully functional array, 1 or 2 for a degraded array. |
1da177e4 | 3409 | */ |
02c2de8c | 3410 | mddev->degraded = conf->raid_disks - working_disks; |
1da177e4 LT |
3411 | conf->mddev = mddev; |
3412 | conf->chunk_size = mddev->chunk_size; | |
3413 | conf->level = mddev->level; | |
16a53ecc N |
3414 | if (conf->level == 6) |
3415 | conf->max_degraded = 2; | |
3416 | else | |
3417 | conf->max_degraded = 1; | |
1da177e4 LT |
3418 | conf->algorithm = mddev->layout; |
3419 | conf->max_nr_stripes = NR_STRIPES; | |
f6705578 | 3420 | conf->expand_progress = mddev->reshape_position; |
1da177e4 LT |
3421 | |
3422 | /* device size must be a multiple of chunk size */ | |
3423 | mddev->size &= ~(mddev->chunk_size/1024 -1); | |
b1581566 | 3424 | mddev->resync_max_sectors = mddev->size << 1; |
1da177e4 | 3425 | |
16a53ecc N |
3426 | if (conf->level == 6 && conf->raid_disks < 4) { |
3427 | printk(KERN_ERR "raid6: not enough configured devices for %s (%d, minimum 4)\n", | |
3428 | mdname(mddev), conf->raid_disks); | |
3429 | goto abort; | |
3430 | } | |
1da177e4 LT |
3431 | if (!conf->chunk_size || conf->chunk_size % 4) { |
3432 | printk(KERN_ERR "raid5: invalid chunk size %d for %s\n", | |
3433 | conf->chunk_size, mdname(mddev)); | |
3434 | goto abort; | |
3435 | } | |
3436 | if (conf->algorithm > ALGORITHM_RIGHT_SYMMETRIC) { | |
3437 | printk(KERN_ERR | |
3438 | "raid5: unsupported parity algorithm %d for %s\n", | |
3439 | conf->algorithm, mdname(mddev)); | |
3440 | goto abort; | |
3441 | } | |
16a53ecc | 3442 | if (mddev->degraded > conf->max_degraded) { |
1da177e4 LT |
3443 | printk(KERN_ERR "raid5: not enough operational devices for %s" |
3444 | " (%d/%d failed)\n", | |
02c2de8c | 3445 | mdname(mddev), mddev->degraded, conf->raid_disks); |
1da177e4 LT |
3446 | goto abort; |
3447 | } | |
3448 | ||
16a53ecc | 3449 | if (mddev->degraded > 0 && |
1da177e4 | 3450 | mddev->recovery_cp != MaxSector) { |
6ff8d8ec N |
3451 | if (mddev->ok_start_degraded) |
3452 | printk(KERN_WARNING | |
3453 | "raid5: starting dirty degraded array: %s" | |
3454 | "- data corruption possible.\n", | |
3455 | mdname(mddev)); | |
3456 | else { | |
3457 | printk(KERN_ERR | |
3458 | "raid5: cannot start dirty degraded array for %s\n", | |
3459 | mdname(mddev)); | |
3460 | goto abort; | |
3461 | } | |
1da177e4 LT |
3462 | } |
3463 | ||
3464 | { | |
3465 | mddev->thread = md_register_thread(raid5d, mddev, "%s_raid5"); | |
3466 | if (!mddev->thread) { | |
3467 | printk(KERN_ERR | |
3468 | "raid5: couldn't allocate thread for %s\n", | |
3469 | mdname(mddev)); | |
3470 | goto abort; | |
3471 | } | |
3472 | } | |
5036805b | 3473 | memory = conf->max_nr_stripes * (sizeof(struct stripe_head) + |
1da177e4 LT |
3474 | conf->raid_disks * ((sizeof(struct bio) + PAGE_SIZE))) / 1024; |
3475 | if (grow_stripes(conf, conf->max_nr_stripes)) { | |
3476 | printk(KERN_ERR | |
3477 | "raid5: couldn't allocate %dkB for buffers\n", memory); | |
3478 | shrink_stripes(conf); | |
3479 | md_unregister_thread(mddev->thread); | |
3480 | goto abort; | |
3481 | } else | |
3482 | printk(KERN_INFO "raid5: allocated %dkB for %s\n", | |
3483 | memory, mdname(mddev)); | |
3484 | ||
3485 | if (mddev->degraded == 0) | |
3486 | printk("raid5: raid level %d set %s active with %d out of %d" | |
3487 | " devices, algorithm %d\n", conf->level, mdname(mddev), | |
3488 | mddev->raid_disks-mddev->degraded, mddev->raid_disks, | |
3489 | conf->algorithm); | |
3490 | else | |
3491 | printk(KERN_ALERT "raid5: raid level %d set %s active with %d" | |
3492 | " out of %d devices, algorithm %d\n", conf->level, | |
3493 | mdname(mddev), mddev->raid_disks - mddev->degraded, | |
3494 | mddev->raid_disks, conf->algorithm); | |
3495 | ||
3496 | print_raid5_conf(conf); | |
3497 | ||
f6705578 N |
3498 | if (conf->expand_progress != MaxSector) { |
3499 | printk("...ok start reshape thread\n"); | |
b578d55f | 3500 | conf->expand_lo = conf->expand_progress; |
f6705578 N |
3501 | atomic_set(&conf->reshape_stripes, 0); |
3502 | clear_bit(MD_RECOVERY_SYNC, &mddev->recovery); | |
3503 | clear_bit(MD_RECOVERY_CHECK, &mddev->recovery); | |
3504 | set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery); | |
3505 | set_bit(MD_RECOVERY_RUNNING, &mddev->recovery); | |
3506 | mddev->sync_thread = md_register_thread(md_do_sync, mddev, | |
3507 | "%s_reshape"); | |
f6705578 N |
3508 | } |
3509 | ||
1da177e4 | 3510 | /* read-ahead size must cover two whole stripes, which is |
16a53ecc | 3511 | * 2 * (datadisks) * chunksize where 'n' is the number of raid devices |
1da177e4 LT |
3512 | */ |
3513 | { | |
16a53ecc N |
3514 | int data_disks = conf->previous_raid_disks - conf->max_degraded; |
3515 | int stripe = data_disks * | |
8932c2e0 | 3516 | (mddev->chunk_size / PAGE_SIZE); |
1da177e4 LT |
3517 | if (mddev->queue->backing_dev_info.ra_pages < 2 * stripe) |
3518 | mddev->queue->backing_dev_info.ra_pages = 2 * stripe; | |
3519 | } | |
3520 | ||
3521 | /* Ok, everything is just fine now */ | |
007583c9 | 3522 | sysfs_create_group(&mddev->kobj, &raid5_attrs_group); |
7a5febe9 N |
3523 | |
3524 | mddev->queue->unplug_fn = raid5_unplug_device; | |
3525 | mddev->queue->issue_flush_fn = raid5_issue_flush; | |
f022b2fd N |
3526 | mddev->queue->backing_dev_info.congested_fn = raid5_congested; |
3527 | mddev->queue->backing_dev_info.congested_data = mddev; | |
3528 | ||
16a53ecc N |
3529 | mddev->array_size = mddev->size * (conf->previous_raid_disks - |
3530 | conf->max_degraded); | |
7a5febe9 | 3531 | |
23032a0e RBJ |
3532 | blk_queue_merge_bvec(mddev->queue, raid5_mergeable_bvec); |
3533 | ||
1da177e4 LT |
3534 | return 0; |
3535 | abort: | |
3536 | if (conf) { | |
3537 | print_raid5_conf(conf); | |
16a53ecc | 3538 | safe_put_page(conf->spare_page); |
b55e6bfc | 3539 | kfree(conf->disks); |
fccddba0 | 3540 | kfree(conf->stripe_hashtbl); |
1da177e4 LT |
3541 | kfree(conf); |
3542 | } | |
3543 | mddev->private = NULL; | |
3544 | printk(KERN_ALERT "raid5: failed to run raid set %s\n", mdname(mddev)); | |
3545 | return -EIO; | |
3546 | } | |
3547 | ||
3548 | ||
3549 | ||
3f294f4f | 3550 | static int stop(mddev_t *mddev) |
1da177e4 LT |
3551 | { |
3552 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; | |
3553 | ||
3554 | md_unregister_thread(mddev->thread); | |
3555 | mddev->thread = NULL; | |
3556 | shrink_stripes(conf); | |
fccddba0 | 3557 | kfree(conf->stripe_hashtbl); |
1da177e4 | 3558 | blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/ |
007583c9 | 3559 | sysfs_remove_group(&mddev->kobj, &raid5_attrs_group); |
b55e6bfc | 3560 | kfree(conf->disks); |
96de1e66 | 3561 | kfree(conf); |
1da177e4 LT |
3562 | mddev->private = NULL; |
3563 | return 0; | |
3564 | } | |
3565 | ||
3566 | #if RAID5_DEBUG | |
16a53ecc | 3567 | static void print_sh (struct seq_file *seq, struct stripe_head *sh) |
1da177e4 LT |
3568 | { |
3569 | int i; | |
3570 | ||
16a53ecc N |
3571 | seq_printf(seq, "sh %llu, pd_idx %d, state %ld.\n", |
3572 | (unsigned long long)sh->sector, sh->pd_idx, sh->state); | |
3573 | seq_printf(seq, "sh %llu, count %d.\n", | |
3574 | (unsigned long long)sh->sector, atomic_read(&sh->count)); | |
3575 | seq_printf(seq, "sh %llu, ", (unsigned long long)sh->sector); | |
7ecaa1e6 | 3576 | for (i = 0; i < sh->disks; i++) { |
16a53ecc N |
3577 | seq_printf(seq, "(cache%d: %p %ld) ", |
3578 | i, sh->dev[i].page, sh->dev[i].flags); | |
1da177e4 | 3579 | } |
16a53ecc | 3580 | seq_printf(seq, "\n"); |
1da177e4 LT |
3581 | } |
3582 | ||
16a53ecc | 3583 | static void printall (struct seq_file *seq, raid5_conf_t *conf) |
1da177e4 LT |
3584 | { |
3585 | struct stripe_head *sh; | |
fccddba0 | 3586 | struct hlist_node *hn; |
1da177e4 LT |
3587 | int i; |
3588 | ||
3589 | spin_lock_irq(&conf->device_lock); | |
3590 | for (i = 0; i < NR_HASH; i++) { | |
fccddba0 | 3591 | hlist_for_each_entry(sh, hn, &conf->stripe_hashtbl[i], hash) { |
1da177e4 LT |
3592 | if (sh->raid_conf != conf) |
3593 | continue; | |
16a53ecc | 3594 | print_sh(seq, sh); |
1da177e4 LT |
3595 | } |
3596 | } | |
3597 | spin_unlock_irq(&conf->device_lock); | |
3598 | } | |
3599 | #endif | |
3600 | ||
3601 | static void status (struct seq_file *seq, mddev_t *mddev) | |
3602 | { | |
3603 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; | |
3604 | int i; | |
3605 | ||
3606 | seq_printf (seq, " level %d, %dk chunk, algorithm %d", mddev->level, mddev->chunk_size >> 10, mddev->layout); | |
02c2de8c | 3607 | seq_printf (seq, " [%d/%d] [", conf->raid_disks, conf->raid_disks - mddev->degraded); |
1da177e4 LT |
3608 | for (i = 0; i < conf->raid_disks; i++) |
3609 | seq_printf (seq, "%s", | |
3610 | conf->disks[i].rdev && | |
b2d444d7 | 3611 | test_bit(In_sync, &conf->disks[i].rdev->flags) ? "U" : "_"); |
1da177e4 LT |
3612 | seq_printf (seq, "]"); |
3613 | #if RAID5_DEBUG | |
16a53ecc N |
3614 | seq_printf (seq, "\n"); |
3615 | printall(seq, conf); | |
1da177e4 LT |
3616 | #endif |
3617 | } | |
3618 | ||
3619 | static void print_raid5_conf (raid5_conf_t *conf) | |
3620 | { | |
3621 | int i; | |
3622 | struct disk_info *tmp; | |
3623 | ||
3624 | printk("RAID5 conf printout:\n"); | |
3625 | if (!conf) { | |
3626 | printk("(conf==NULL)\n"); | |
3627 | return; | |
3628 | } | |
02c2de8c N |
3629 | printk(" --- rd:%d wd:%d\n", conf->raid_disks, |
3630 | conf->raid_disks - conf->mddev->degraded); | |
1da177e4 LT |
3631 | |
3632 | for (i = 0; i < conf->raid_disks; i++) { | |
3633 | char b[BDEVNAME_SIZE]; | |
3634 | tmp = conf->disks + i; | |
3635 | if (tmp->rdev) | |
3636 | printk(" disk %d, o:%d, dev:%s\n", | |
b2d444d7 | 3637 | i, !test_bit(Faulty, &tmp->rdev->flags), |
1da177e4 LT |
3638 | bdevname(tmp->rdev->bdev,b)); |
3639 | } | |
3640 | } | |
3641 | ||
3642 | static int raid5_spare_active(mddev_t *mddev) | |
3643 | { | |
3644 | int i; | |
3645 | raid5_conf_t *conf = mddev->private; | |
3646 | struct disk_info *tmp; | |
3647 | ||
3648 | for (i = 0; i < conf->raid_disks; i++) { | |
3649 | tmp = conf->disks + i; | |
3650 | if (tmp->rdev | |
b2d444d7 | 3651 | && !test_bit(Faulty, &tmp->rdev->flags) |
c04be0aa N |
3652 | && !test_and_set_bit(In_sync, &tmp->rdev->flags)) { |
3653 | unsigned long flags; | |
3654 | spin_lock_irqsave(&conf->device_lock, flags); | |
1da177e4 | 3655 | mddev->degraded--; |
c04be0aa | 3656 | spin_unlock_irqrestore(&conf->device_lock, flags); |
1da177e4 LT |
3657 | } |
3658 | } | |
3659 | print_raid5_conf(conf); | |
3660 | return 0; | |
3661 | } | |
3662 | ||
3663 | static int raid5_remove_disk(mddev_t *mddev, int number) | |
3664 | { | |
3665 | raid5_conf_t *conf = mddev->private; | |
3666 | int err = 0; | |
3667 | mdk_rdev_t *rdev; | |
3668 | struct disk_info *p = conf->disks + number; | |
3669 | ||
3670 | print_raid5_conf(conf); | |
3671 | rdev = p->rdev; | |
3672 | if (rdev) { | |
b2d444d7 | 3673 | if (test_bit(In_sync, &rdev->flags) || |
1da177e4 LT |
3674 | atomic_read(&rdev->nr_pending)) { |
3675 | err = -EBUSY; | |
3676 | goto abort; | |
3677 | } | |
3678 | p->rdev = NULL; | |
fbd568a3 | 3679 | synchronize_rcu(); |
1da177e4 LT |
3680 | if (atomic_read(&rdev->nr_pending)) { |
3681 | /* lost the race, try later */ | |
3682 | err = -EBUSY; | |
3683 | p->rdev = rdev; | |
3684 | } | |
3685 | } | |
3686 | abort: | |
3687 | ||
3688 | print_raid5_conf(conf); | |
3689 | return err; | |
3690 | } | |
3691 | ||
3692 | static int raid5_add_disk(mddev_t *mddev, mdk_rdev_t *rdev) | |
3693 | { | |
3694 | raid5_conf_t *conf = mddev->private; | |
3695 | int found = 0; | |
3696 | int disk; | |
3697 | struct disk_info *p; | |
3698 | ||
16a53ecc | 3699 | if (mddev->degraded > conf->max_degraded) |
1da177e4 LT |
3700 | /* no point adding a device */ |
3701 | return 0; | |
3702 | ||
3703 | /* | |
16a53ecc N |
3704 | * find the disk ... but prefer rdev->saved_raid_disk |
3705 | * if possible. | |
1da177e4 | 3706 | */ |
16a53ecc N |
3707 | if (rdev->saved_raid_disk >= 0 && |
3708 | conf->disks[rdev->saved_raid_disk].rdev == NULL) | |
3709 | disk = rdev->saved_raid_disk; | |
3710 | else | |
3711 | disk = 0; | |
3712 | for ( ; disk < conf->raid_disks; disk++) | |
1da177e4 | 3713 | if ((p=conf->disks + disk)->rdev == NULL) { |
b2d444d7 | 3714 | clear_bit(In_sync, &rdev->flags); |
1da177e4 LT |
3715 | rdev->raid_disk = disk; |
3716 | found = 1; | |
72626685 N |
3717 | if (rdev->saved_raid_disk != disk) |
3718 | conf->fullsync = 1; | |
d6065f7b | 3719 | rcu_assign_pointer(p->rdev, rdev); |
1da177e4 LT |
3720 | break; |
3721 | } | |
3722 | print_raid5_conf(conf); | |
3723 | return found; | |
3724 | } | |
3725 | ||
3726 | static int raid5_resize(mddev_t *mddev, sector_t sectors) | |
3727 | { | |
3728 | /* no resync is happening, and there is enough space | |
3729 | * on all devices, so we can resize. | |
3730 | * We need to make sure resync covers any new space. | |
3731 | * If the array is shrinking we should possibly wait until | |
3732 | * any io in the removed space completes, but it hardly seems | |
3733 | * worth it. | |
3734 | */ | |
16a53ecc N |
3735 | raid5_conf_t *conf = mddev_to_conf(mddev); |
3736 | ||
1da177e4 | 3737 | sectors &= ~((sector_t)mddev->chunk_size/512 - 1); |
16a53ecc | 3738 | mddev->array_size = (sectors * (mddev->raid_disks-conf->max_degraded))>>1; |
1da177e4 LT |
3739 | set_capacity(mddev->gendisk, mddev->array_size << 1); |
3740 | mddev->changed = 1; | |
3741 | if (sectors/2 > mddev->size && mddev->recovery_cp == MaxSector) { | |
3742 | mddev->recovery_cp = mddev->size << 1; | |
3743 | set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); | |
3744 | } | |
3745 | mddev->size = sectors /2; | |
4b5c7ae8 | 3746 | mddev->resync_max_sectors = sectors; |
1da177e4 LT |
3747 | return 0; |
3748 | } | |
3749 | ||
29269553 | 3750 | #ifdef CONFIG_MD_RAID5_RESHAPE |
63c70c4f | 3751 | static int raid5_check_reshape(mddev_t *mddev) |
29269553 N |
3752 | { |
3753 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
3754 | int err; | |
29269553 | 3755 | |
63c70c4f N |
3756 | if (mddev->delta_disks < 0 || |
3757 | mddev->new_level != mddev->level) | |
3758 | return -EINVAL; /* Cannot shrink array or change level yet */ | |
3759 | if (mddev->delta_disks == 0) | |
29269553 N |
3760 | return 0; /* nothing to do */ |
3761 | ||
3762 | /* Can only proceed if there are plenty of stripe_heads. | |
3763 | * We need a minimum of one full stripe,, and for sensible progress | |
3764 | * it is best to have about 4 times that. | |
3765 | * If we require 4 times, then the default 256 4K stripe_heads will | |
3766 | * allow for chunk sizes up to 256K, which is probably OK. | |
3767 | * If the chunk size is greater, user-space should request more | |
3768 | * stripe_heads first. | |
3769 | */ | |
63c70c4f N |
3770 | if ((mddev->chunk_size / STRIPE_SIZE) * 4 > conf->max_nr_stripes || |
3771 | (mddev->new_chunk / STRIPE_SIZE) * 4 > conf->max_nr_stripes) { | |
29269553 N |
3772 | printk(KERN_WARNING "raid5: reshape: not enough stripes. Needed %lu\n", |
3773 | (mddev->chunk_size / STRIPE_SIZE)*4); | |
3774 | return -ENOSPC; | |
3775 | } | |
3776 | ||
63c70c4f N |
3777 | err = resize_stripes(conf, conf->raid_disks + mddev->delta_disks); |
3778 | if (err) | |
3779 | return err; | |
3780 | ||
3781 | /* looks like we might be able to manage this */ | |
3782 | return 0; | |
3783 | } | |
3784 | ||
3785 | static int raid5_start_reshape(mddev_t *mddev) | |
3786 | { | |
3787 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
3788 | mdk_rdev_t *rdev; | |
3789 | struct list_head *rtmp; | |
3790 | int spares = 0; | |
3791 | int added_devices = 0; | |
c04be0aa | 3792 | unsigned long flags; |
63c70c4f N |
3793 | |
3794 | if (mddev->degraded || | |
3795 | test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) | |
3796 | return -EBUSY; | |
3797 | ||
29269553 N |
3798 | ITERATE_RDEV(mddev, rdev, rtmp) |
3799 | if (rdev->raid_disk < 0 && | |
3800 | !test_bit(Faulty, &rdev->flags)) | |
3801 | spares++; | |
63c70c4f N |
3802 | |
3803 | if (spares < mddev->delta_disks-1) | |
29269553 N |
3804 | /* Not enough devices even to make a degraded array |
3805 | * of that size | |
3806 | */ | |
3807 | return -EINVAL; | |
3808 | ||
f6705578 | 3809 | atomic_set(&conf->reshape_stripes, 0); |
29269553 N |
3810 | spin_lock_irq(&conf->device_lock); |
3811 | conf->previous_raid_disks = conf->raid_disks; | |
63c70c4f | 3812 | conf->raid_disks += mddev->delta_disks; |
29269553 | 3813 | conf->expand_progress = 0; |
b578d55f | 3814 | conf->expand_lo = 0; |
29269553 N |
3815 | spin_unlock_irq(&conf->device_lock); |
3816 | ||
3817 | /* Add some new drives, as many as will fit. | |
3818 | * We know there are enough to make the newly sized array work. | |
3819 | */ | |
3820 | ITERATE_RDEV(mddev, rdev, rtmp) | |
3821 | if (rdev->raid_disk < 0 && | |
3822 | !test_bit(Faulty, &rdev->flags)) { | |
3823 | if (raid5_add_disk(mddev, rdev)) { | |
3824 | char nm[20]; | |
3825 | set_bit(In_sync, &rdev->flags); | |
29269553 | 3826 | added_devices++; |
5fd6c1dc | 3827 | rdev->recovery_offset = 0; |
29269553 N |
3828 | sprintf(nm, "rd%d", rdev->raid_disk); |
3829 | sysfs_create_link(&mddev->kobj, &rdev->kobj, nm); | |
3830 | } else | |
3831 | break; | |
3832 | } | |
3833 | ||
c04be0aa | 3834 | spin_lock_irqsave(&conf->device_lock, flags); |
63c70c4f | 3835 | mddev->degraded = (conf->raid_disks - conf->previous_raid_disks) - added_devices; |
c04be0aa | 3836 | spin_unlock_irqrestore(&conf->device_lock, flags); |
63c70c4f | 3837 | mddev->raid_disks = conf->raid_disks; |
f6705578 | 3838 | mddev->reshape_position = 0; |
850b2b42 | 3839 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
f6705578 | 3840 | |
29269553 N |
3841 | clear_bit(MD_RECOVERY_SYNC, &mddev->recovery); |
3842 | clear_bit(MD_RECOVERY_CHECK, &mddev->recovery); | |
3843 | set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery); | |
3844 | set_bit(MD_RECOVERY_RUNNING, &mddev->recovery); | |
3845 | mddev->sync_thread = md_register_thread(md_do_sync, mddev, | |
3846 | "%s_reshape"); | |
3847 | if (!mddev->sync_thread) { | |
3848 | mddev->recovery = 0; | |
3849 | spin_lock_irq(&conf->device_lock); | |
3850 | mddev->raid_disks = conf->raid_disks = conf->previous_raid_disks; | |
3851 | conf->expand_progress = MaxSector; | |
3852 | spin_unlock_irq(&conf->device_lock); | |
3853 | return -EAGAIN; | |
3854 | } | |
3855 | md_wakeup_thread(mddev->sync_thread); | |
3856 | md_new_event(mddev); | |
3857 | return 0; | |
3858 | } | |
3859 | #endif | |
3860 | ||
3861 | static void end_reshape(raid5_conf_t *conf) | |
3862 | { | |
3863 | struct block_device *bdev; | |
3864 | ||
f6705578 N |
3865 | if (!test_bit(MD_RECOVERY_INTR, &conf->mddev->recovery)) { |
3866 | conf->mddev->array_size = conf->mddev->size * (conf->raid_disks-1); | |
3867 | set_capacity(conf->mddev->gendisk, conf->mddev->array_size << 1); | |
3868 | conf->mddev->changed = 1; | |
3869 | ||
3870 | bdev = bdget_disk(conf->mddev->gendisk, 0); | |
3871 | if (bdev) { | |
3872 | mutex_lock(&bdev->bd_inode->i_mutex); | |
0692c6b1 | 3873 | i_size_write(bdev->bd_inode, (loff_t)conf->mddev->array_size << 10); |
f6705578 N |
3874 | mutex_unlock(&bdev->bd_inode->i_mutex); |
3875 | bdput(bdev); | |
3876 | } | |
3877 | spin_lock_irq(&conf->device_lock); | |
3878 | conf->expand_progress = MaxSector; | |
3879 | spin_unlock_irq(&conf->device_lock); | |
3880 | conf->mddev->reshape_position = MaxSector; | |
16a53ecc N |
3881 | |
3882 | /* read-ahead size must cover two whole stripes, which is | |
3883 | * 2 * (datadisks) * chunksize where 'n' is the number of raid devices | |
3884 | */ | |
3885 | { | |
3886 | int data_disks = conf->previous_raid_disks - conf->max_degraded; | |
3887 | int stripe = data_disks * | |
3888 | (conf->mddev->chunk_size / PAGE_SIZE); | |
3889 | if (conf->mddev->queue->backing_dev_info.ra_pages < 2 * stripe) | |
3890 | conf->mddev->queue->backing_dev_info.ra_pages = 2 * stripe; | |
3891 | } | |
29269553 | 3892 | } |
29269553 N |
3893 | } |
3894 | ||
72626685 N |
3895 | static void raid5_quiesce(mddev_t *mddev, int state) |
3896 | { | |
3897 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
3898 | ||
3899 | switch(state) { | |
e464eafd N |
3900 | case 2: /* resume for a suspend */ |
3901 | wake_up(&conf->wait_for_overlap); | |
3902 | break; | |
3903 | ||
72626685 N |
3904 | case 1: /* stop all writes */ |
3905 | spin_lock_irq(&conf->device_lock); | |
3906 | conf->quiesce = 1; | |
3907 | wait_event_lock_irq(conf->wait_for_stripe, | |
46031f9a RBJ |
3908 | atomic_read(&conf->active_stripes) == 0 && |
3909 | atomic_read(&conf->active_aligned_reads) == 0, | |
72626685 N |
3910 | conf->device_lock, /* nothing */); |
3911 | spin_unlock_irq(&conf->device_lock); | |
3912 | break; | |
3913 | ||
3914 | case 0: /* re-enable writes */ | |
3915 | spin_lock_irq(&conf->device_lock); | |
3916 | conf->quiesce = 0; | |
3917 | wake_up(&conf->wait_for_stripe); | |
e464eafd | 3918 | wake_up(&conf->wait_for_overlap); |
72626685 N |
3919 | spin_unlock_irq(&conf->device_lock); |
3920 | break; | |
3921 | } | |
72626685 | 3922 | } |
b15c2e57 | 3923 | |
16a53ecc N |
3924 | static struct mdk_personality raid6_personality = |
3925 | { | |
3926 | .name = "raid6", | |
3927 | .level = 6, | |
3928 | .owner = THIS_MODULE, | |
3929 | .make_request = make_request, | |
3930 | .run = run, | |
3931 | .stop = stop, | |
3932 | .status = status, | |
3933 | .error_handler = error, | |
3934 | .hot_add_disk = raid5_add_disk, | |
3935 | .hot_remove_disk= raid5_remove_disk, | |
3936 | .spare_active = raid5_spare_active, | |
3937 | .sync_request = sync_request, | |
3938 | .resize = raid5_resize, | |
3939 | .quiesce = raid5_quiesce, | |
3940 | }; | |
2604b703 | 3941 | static struct mdk_personality raid5_personality = |
1da177e4 LT |
3942 | { |
3943 | .name = "raid5", | |
2604b703 | 3944 | .level = 5, |
1da177e4 LT |
3945 | .owner = THIS_MODULE, |
3946 | .make_request = make_request, | |
3947 | .run = run, | |
3948 | .stop = stop, | |
3949 | .status = status, | |
3950 | .error_handler = error, | |
3951 | .hot_add_disk = raid5_add_disk, | |
3952 | .hot_remove_disk= raid5_remove_disk, | |
3953 | .spare_active = raid5_spare_active, | |
3954 | .sync_request = sync_request, | |
3955 | .resize = raid5_resize, | |
29269553 | 3956 | #ifdef CONFIG_MD_RAID5_RESHAPE |
63c70c4f N |
3957 | .check_reshape = raid5_check_reshape, |
3958 | .start_reshape = raid5_start_reshape, | |
29269553 | 3959 | #endif |
72626685 | 3960 | .quiesce = raid5_quiesce, |
1da177e4 LT |
3961 | }; |
3962 | ||
2604b703 | 3963 | static struct mdk_personality raid4_personality = |
1da177e4 | 3964 | { |
2604b703 N |
3965 | .name = "raid4", |
3966 | .level = 4, | |
3967 | .owner = THIS_MODULE, | |
3968 | .make_request = make_request, | |
3969 | .run = run, | |
3970 | .stop = stop, | |
3971 | .status = status, | |
3972 | .error_handler = error, | |
3973 | .hot_add_disk = raid5_add_disk, | |
3974 | .hot_remove_disk= raid5_remove_disk, | |
3975 | .spare_active = raid5_spare_active, | |
3976 | .sync_request = sync_request, | |
3977 | .resize = raid5_resize, | |
3978 | .quiesce = raid5_quiesce, | |
3979 | }; | |
3980 | ||
3981 | static int __init raid5_init(void) | |
3982 | { | |
16a53ecc N |
3983 | int e; |
3984 | ||
3985 | e = raid6_select_algo(); | |
3986 | if ( e ) | |
3987 | return e; | |
3988 | register_md_personality(&raid6_personality); | |
2604b703 N |
3989 | register_md_personality(&raid5_personality); |
3990 | register_md_personality(&raid4_personality); | |
3991 | return 0; | |
1da177e4 LT |
3992 | } |
3993 | ||
2604b703 | 3994 | static void raid5_exit(void) |
1da177e4 | 3995 | { |
16a53ecc | 3996 | unregister_md_personality(&raid6_personality); |
2604b703 N |
3997 | unregister_md_personality(&raid5_personality); |
3998 | unregister_md_personality(&raid4_personality); | |
1da177e4 LT |
3999 | } |
4000 | ||
4001 | module_init(raid5_init); | |
4002 | module_exit(raid5_exit); | |
4003 | MODULE_LICENSE("GPL"); | |
4004 | MODULE_ALIAS("md-personality-4"); /* RAID5 */ | |
d9d166c2 N |
4005 | MODULE_ALIAS("md-raid5"); |
4006 | MODULE_ALIAS("md-raid4"); | |
2604b703 N |
4007 | MODULE_ALIAS("md-level-5"); |
4008 | MODULE_ALIAS("md-level-4"); | |
16a53ecc N |
4009 | MODULE_ALIAS("md-personality-8"); /* RAID6 */ |
4010 | MODULE_ALIAS("md-raid6"); | |
4011 | MODULE_ALIAS("md-level-6"); | |
4012 | ||
4013 | /* This used to be two separate modules, they were: */ | |
4014 | MODULE_ALIAS("raid5"); | |
4015 | MODULE_ALIAS("raid6"); |