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 | ||
21 | ||
1da177e4 LT |
22 | #include <linux/module.h> |
23 | #include <linux/slab.h> | |
1da177e4 LT |
24 | #include <linux/highmem.h> |
25 | #include <linux/bitops.h> | |
f6705578 | 26 | #include <linux/kthread.h> |
1da177e4 | 27 | #include <asm/atomic.h> |
16a53ecc | 28 | #include "raid6.h" |
1da177e4 | 29 | |
72626685 N |
30 | #include <linux/raid/bitmap.h> |
31 | ||
1da177e4 LT |
32 | /* |
33 | * Stripe cache | |
34 | */ | |
35 | ||
36 | #define NR_STRIPES 256 | |
37 | #define STRIPE_SIZE PAGE_SIZE | |
38 | #define STRIPE_SHIFT (PAGE_SHIFT - 9) | |
39 | #define STRIPE_SECTORS (STRIPE_SIZE>>9) | |
40 | #define IO_THRESHOLD 1 | |
fccddba0 | 41 | #define NR_HASH (PAGE_SIZE / sizeof(struct hlist_head)) |
1da177e4 LT |
42 | #define HASH_MASK (NR_HASH - 1) |
43 | ||
fccddba0 | 44 | #define stripe_hash(conf, sect) (&((conf)->stripe_hashtbl[((sect) >> STRIPE_SHIFT) & HASH_MASK])) |
1da177e4 LT |
45 | |
46 | /* bio's attached to a stripe+device for I/O are linked together in bi_sector | |
47 | * order without overlap. There may be several bio's per stripe+device, and | |
48 | * a bio could span several devices. | |
49 | * When walking this list for a particular stripe+device, we must never proceed | |
50 | * beyond a bio that extends past this device, as the next bio might no longer | |
51 | * be valid. | |
52 | * This macro is used to determine the 'next' bio in the list, given the sector | |
53 | * of the current stripe+device | |
54 | */ | |
55 | #define r5_next_bio(bio, sect) ( ( (bio)->bi_sector + ((bio)->bi_size>>9) < sect + STRIPE_SECTORS) ? (bio)->bi_next : NULL) | |
56 | /* | |
57 | * The following can be used to debug the driver | |
58 | */ | |
59 | #define RAID5_DEBUG 0 | |
60 | #define RAID5_PARANOIA 1 | |
61 | #if RAID5_PARANOIA && defined(CONFIG_SMP) | |
62 | # define CHECK_DEVLOCK() assert_spin_locked(&conf->device_lock) | |
63 | #else | |
64 | # define CHECK_DEVLOCK() | |
65 | #endif | |
66 | ||
67 | #define PRINTK(x...) ((void)(RAID5_DEBUG && printk(x))) | |
68 | #if RAID5_DEBUG | |
69 | #define inline | |
70 | #define __inline__ | |
71 | #endif | |
72 | ||
16a53ecc N |
73 | #if !RAID6_USE_EMPTY_ZERO_PAGE |
74 | /* In .bss so it's zeroed */ | |
75 | const char raid6_empty_zero_page[PAGE_SIZE] __attribute__((aligned(256))); | |
76 | #endif | |
77 | ||
78 | static inline int raid6_next_disk(int disk, int raid_disks) | |
79 | { | |
80 | disk++; | |
81 | return (disk < raid_disks) ? disk : 0; | |
82 | } | |
1da177e4 LT |
83 | static void print_raid5_conf (raid5_conf_t *conf); |
84 | ||
858119e1 | 85 | static void __release_stripe(raid5_conf_t *conf, struct stripe_head *sh) |
1da177e4 LT |
86 | { |
87 | if (atomic_dec_and_test(&sh->count)) { | |
78bafebd ES |
88 | BUG_ON(!list_empty(&sh->lru)); |
89 | BUG_ON(atomic_read(&conf->active_stripes)==0); | |
1da177e4 LT |
90 | if (test_bit(STRIPE_HANDLE, &sh->state)) { |
91 | if (test_bit(STRIPE_DELAYED, &sh->state)) | |
92 | list_add_tail(&sh->lru, &conf->delayed_list); | |
72626685 N |
93 | else if (test_bit(STRIPE_BIT_DELAY, &sh->state) && |
94 | conf->seq_write == sh->bm_seq) | |
95 | list_add_tail(&sh->lru, &conf->bitmap_list); | |
96 | else { | |
97 | clear_bit(STRIPE_BIT_DELAY, &sh->state); | |
1da177e4 | 98 | list_add_tail(&sh->lru, &conf->handle_list); |
72626685 | 99 | } |
1da177e4 LT |
100 | md_wakeup_thread(conf->mddev->thread); |
101 | } else { | |
102 | if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
103 | atomic_dec(&conf->preread_active_stripes); | |
104 | if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD) | |
105 | md_wakeup_thread(conf->mddev->thread); | |
106 | } | |
1da177e4 | 107 | atomic_dec(&conf->active_stripes); |
ccfcc3c1 N |
108 | if (!test_bit(STRIPE_EXPANDING, &sh->state)) { |
109 | list_add_tail(&sh->lru, &conf->inactive_list); | |
1da177e4 | 110 | wake_up(&conf->wait_for_stripe); |
ccfcc3c1 | 111 | } |
1da177e4 LT |
112 | } |
113 | } | |
114 | } | |
115 | static void release_stripe(struct stripe_head *sh) | |
116 | { | |
117 | raid5_conf_t *conf = sh->raid_conf; | |
118 | unsigned long flags; | |
16a53ecc | 119 | |
1da177e4 LT |
120 | spin_lock_irqsave(&conf->device_lock, flags); |
121 | __release_stripe(conf, sh); | |
122 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
123 | } | |
124 | ||
fccddba0 | 125 | static inline void remove_hash(struct stripe_head *sh) |
1da177e4 LT |
126 | { |
127 | PRINTK("remove_hash(), stripe %llu\n", (unsigned long long)sh->sector); | |
128 | ||
fccddba0 | 129 | hlist_del_init(&sh->hash); |
1da177e4 LT |
130 | } |
131 | ||
16a53ecc | 132 | static inline void insert_hash(raid5_conf_t *conf, struct stripe_head *sh) |
1da177e4 | 133 | { |
fccddba0 | 134 | struct hlist_head *hp = stripe_hash(conf, sh->sector); |
1da177e4 LT |
135 | |
136 | PRINTK("insert_hash(), stripe %llu\n", (unsigned long long)sh->sector); | |
137 | ||
138 | CHECK_DEVLOCK(); | |
fccddba0 | 139 | hlist_add_head(&sh->hash, hp); |
1da177e4 LT |
140 | } |
141 | ||
142 | ||
143 | /* find an idle stripe, make sure it is unhashed, and return it. */ | |
144 | static struct stripe_head *get_free_stripe(raid5_conf_t *conf) | |
145 | { | |
146 | struct stripe_head *sh = NULL; | |
147 | struct list_head *first; | |
148 | ||
149 | CHECK_DEVLOCK(); | |
150 | if (list_empty(&conf->inactive_list)) | |
151 | goto out; | |
152 | first = conf->inactive_list.next; | |
153 | sh = list_entry(first, struct stripe_head, lru); | |
154 | list_del_init(first); | |
155 | remove_hash(sh); | |
156 | atomic_inc(&conf->active_stripes); | |
157 | out: | |
158 | return sh; | |
159 | } | |
160 | ||
161 | static void shrink_buffers(struct stripe_head *sh, int num) | |
162 | { | |
163 | struct page *p; | |
164 | int i; | |
165 | ||
166 | for (i=0; i<num ; i++) { | |
167 | p = sh->dev[i].page; | |
168 | if (!p) | |
169 | continue; | |
170 | sh->dev[i].page = NULL; | |
2d1f3b5d | 171 | put_page(p); |
1da177e4 LT |
172 | } |
173 | } | |
174 | ||
175 | static int grow_buffers(struct stripe_head *sh, int num) | |
176 | { | |
177 | int i; | |
178 | ||
179 | for (i=0; i<num; i++) { | |
180 | struct page *page; | |
181 | ||
182 | if (!(page = alloc_page(GFP_KERNEL))) { | |
183 | return 1; | |
184 | } | |
185 | sh->dev[i].page = page; | |
186 | } | |
187 | return 0; | |
188 | } | |
189 | ||
190 | static void raid5_build_block (struct stripe_head *sh, int i); | |
191 | ||
7ecaa1e6 | 192 | static void init_stripe(struct stripe_head *sh, sector_t sector, int pd_idx, int disks) |
1da177e4 LT |
193 | { |
194 | raid5_conf_t *conf = sh->raid_conf; | |
7ecaa1e6 | 195 | int i; |
1da177e4 | 196 | |
78bafebd ES |
197 | BUG_ON(atomic_read(&sh->count) != 0); |
198 | BUG_ON(test_bit(STRIPE_HANDLE, &sh->state)); | |
1da177e4 LT |
199 | |
200 | CHECK_DEVLOCK(); | |
201 | PRINTK("init_stripe called, stripe %llu\n", | |
202 | (unsigned long long)sh->sector); | |
203 | ||
204 | remove_hash(sh); | |
16a53ecc | 205 | |
1da177e4 LT |
206 | sh->sector = sector; |
207 | sh->pd_idx = pd_idx; | |
208 | sh->state = 0; | |
209 | ||
7ecaa1e6 N |
210 | sh->disks = disks; |
211 | ||
212 | for (i = sh->disks; i--; ) { | |
1da177e4 LT |
213 | struct r5dev *dev = &sh->dev[i]; |
214 | ||
215 | if (dev->toread || dev->towrite || dev->written || | |
216 | test_bit(R5_LOCKED, &dev->flags)) { | |
217 | printk("sector=%llx i=%d %p %p %p %d\n", | |
218 | (unsigned long long)sh->sector, i, dev->toread, | |
219 | dev->towrite, dev->written, | |
220 | test_bit(R5_LOCKED, &dev->flags)); | |
221 | BUG(); | |
222 | } | |
223 | dev->flags = 0; | |
224 | raid5_build_block(sh, i); | |
225 | } | |
226 | insert_hash(conf, sh); | |
227 | } | |
228 | ||
7ecaa1e6 | 229 | static struct stripe_head *__find_stripe(raid5_conf_t *conf, sector_t sector, int disks) |
1da177e4 LT |
230 | { |
231 | struct stripe_head *sh; | |
fccddba0 | 232 | struct hlist_node *hn; |
1da177e4 LT |
233 | |
234 | CHECK_DEVLOCK(); | |
235 | PRINTK("__find_stripe, sector %llu\n", (unsigned long long)sector); | |
fccddba0 | 236 | hlist_for_each_entry(sh, hn, stripe_hash(conf, sector), hash) |
7ecaa1e6 | 237 | if (sh->sector == sector && sh->disks == disks) |
1da177e4 LT |
238 | return sh; |
239 | PRINTK("__stripe %llu not in cache\n", (unsigned long long)sector); | |
240 | return NULL; | |
241 | } | |
242 | ||
243 | static void unplug_slaves(mddev_t *mddev); | |
244 | static void raid5_unplug_device(request_queue_t *q); | |
245 | ||
7ecaa1e6 N |
246 | static struct stripe_head *get_active_stripe(raid5_conf_t *conf, sector_t sector, int disks, |
247 | int pd_idx, int noblock) | |
1da177e4 LT |
248 | { |
249 | struct stripe_head *sh; | |
250 | ||
251 | PRINTK("get_stripe, sector %llu\n", (unsigned long long)sector); | |
252 | ||
253 | spin_lock_irq(&conf->device_lock); | |
254 | ||
255 | do { | |
72626685 N |
256 | wait_event_lock_irq(conf->wait_for_stripe, |
257 | conf->quiesce == 0, | |
258 | conf->device_lock, /* nothing */); | |
7ecaa1e6 | 259 | sh = __find_stripe(conf, sector, disks); |
1da177e4 LT |
260 | if (!sh) { |
261 | if (!conf->inactive_blocked) | |
262 | sh = get_free_stripe(conf); | |
263 | if (noblock && sh == NULL) | |
264 | break; | |
265 | if (!sh) { | |
266 | conf->inactive_blocked = 1; | |
267 | wait_event_lock_irq(conf->wait_for_stripe, | |
268 | !list_empty(&conf->inactive_list) && | |
5036805b N |
269 | (atomic_read(&conf->active_stripes) |
270 | < (conf->max_nr_stripes *3/4) | |
1da177e4 LT |
271 | || !conf->inactive_blocked), |
272 | conf->device_lock, | |
f4370781 | 273 | raid5_unplug_device(conf->mddev->queue) |
1da177e4 LT |
274 | ); |
275 | conf->inactive_blocked = 0; | |
276 | } else | |
7ecaa1e6 | 277 | init_stripe(sh, sector, pd_idx, disks); |
1da177e4 LT |
278 | } else { |
279 | if (atomic_read(&sh->count)) { | |
78bafebd | 280 | BUG_ON(!list_empty(&sh->lru)); |
1da177e4 LT |
281 | } else { |
282 | if (!test_bit(STRIPE_HANDLE, &sh->state)) | |
283 | atomic_inc(&conf->active_stripes); | |
16a53ecc N |
284 | if (list_empty(&sh->lru)) |
285 | BUG(); | |
286 | list_del_init(&sh->lru); | |
1da177e4 LT |
287 | } |
288 | } | |
289 | } while (sh == NULL); | |
290 | ||
291 | if (sh) | |
292 | atomic_inc(&sh->count); | |
293 | ||
294 | spin_unlock_irq(&conf->device_lock); | |
295 | return sh; | |
296 | } | |
297 | ||
3f294f4f | 298 | static int grow_one_stripe(raid5_conf_t *conf) |
1da177e4 LT |
299 | { |
300 | struct stripe_head *sh; | |
3f294f4f N |
301 | sh = kmem_cache_alloc(conf->slab_cache, GFP_KERNEL); |
302 | if (!sh) | |
303 | return 0; | |
304 | memset(sh, 0, sizeof(*sh) + (conf->raid_disks-1)*sizeof(struct r5dev)); | |
305 | sh->raid_conf = conf; | |
306 | spin_lock_init(&sh->lock); | |
307 | ||
308 | if (grow_buffers(sh, conf->raid_disks)) { | |
309 | shrink_buffers(sh, conf->raid_disks); | |
310 | kmem_cache_free(conf->slab_cache, sh); | |
311 | return 0; | |
312 | } | |
7ecaa1e6 | 313 | sh->disks = conf->raid_disks; |
3f294f4f N |
314 | /* we just created an active stripe so... */ |
315 | atomic_set(&sh->count, 1); | |
316 | atomic_inc(&conf->active_stripes); | |
317 | INIT_LIST_HEAD(&sh->lru); | |
318 | release_stripe(sh); | |
319 | return 1; | |
320 | } | |
321 | ||
322 | static int grow_stripes(raid5_conf_t *conf, int num) | |
323 | { | |
1da177e4 LT |
324 | kmem_cache_t *sc; |
325 | int devs = conf->raid_disks; | |
326 | ||
ad01c9e3 N |
327 | sprintf(conf->cache_name[0], "raid5/%s", mdname(conf->mddev)); |
328 | sprintf(conf->cache_name[1], "raid5/%s-alt", mdname(conf->mddev)); | |
329 | conf->active_name = 0; | |
330 | sc = kmem_cache_create(conf->cache_name[conf->active_name], | |
1da177e4 LT |
331 | sizeof(struct stripe_head)+(devs-1)*sizeof(struct r5dev), |
332 | 0, 0, NULL, NULL); | |
333 | if (!sc) | |
334 | return 1; | |
335 | conf->slab_cache = sc; | |
ad01c9e3 | 336 | conf->pool_size = devs; |
16a53ecc | 337 | while (num--) |
3f294f4f | 338 | if (!grow_one_stripe(conf)) |
1da177e4 | 339 | return 1; |
1da177e4 LT |
340 | return 0; |
341 | } | |
29269553 N |
342 | |
343 | #ifdef CONFIG_MD_RAID5_RESHAPE | |
ad01c9e3 N |
344 | static int resize_stripes(raid5_conf_t *conf, int newsize) |
345 | { | |
346 | /* Make all the stripes able to hold 'newsize' devices. | |
347 | * New slots in each stripe get 'page' set to a new page. | |
348 | * | |
349 | * This happens in stages: | |
350 | * 1/ create a new kmem_cache and allocate the required number of | |
351 | * stripe_heads. | |
352 | * 2/ gather all the old stripe_heads and tranfer the pages across | |
353 | * to the new stripe_heads. This will have the side effect of | |
354 | * freezing the array as once all stripe_heads have been collected, | |
355 | * no IO will be possible. Old stripe heads are freed once their | |
356 | * pages have been transferred over, and the old kmem_cache is | |
357 | * freed when all stripes are done. | |
358 | * 3/ reallocate conf->disks to be suitable bigger. If this fails, | |
359 | * we simple return a failre status - no need to clean anything up. | |
360 | * 4/ allocate new pages for the new slots in the new stripe_heads. | |
361 | * If this fails, we don't bother trying the shrink the | |
362 | * stripe_heads down again, we just leave them as they are. | |
363 | * As each stripe_head is processed the new one is released into | |
364 | * active service. | |
365 | * | |
366 | * Once step2 is started, we cannot afford to wait for a write, | |
367 | * so we use GFP_NOIO allocations. | |
368 | */ | |
369 | struct stripe_head *osh, *nsh; | |
370 | LIST_HEAD(newstripes); | |
371 | struct disk_info *ndisks; | |
372 | int err = 0; | |
373 | kmem_cache_t *sc; | |
374 | int i; | |
375 | ||
376 | if (newsize <= conf->pool_size) | |
377 | return 0; /* never bother to shrink */ | |
378 | ||
379 | /* Step 1 */ | |
380 | sc = kmem_cache_create(conf->cache_name[1-conf->active_name], | |
381 | sizeof(struct stripe_head)+(newsize-1)*sizeof(struct r5dev), | |
382 | 0, 0, NULL, NULL); | |
383 | if (!sc) | |
384 | return -ENOMEM; | |
385 | ||
386 | for (i = conf->max_nr_stripes; i; i--) { | |
387 | nsh = kmem_cache_alloc(sc, GFP_KERNEL); | |
388 | if (!nsh) | |
389 | break; | |
390 | ||
391 | memset(nsh, 0, sizeof(*nsh) + (newsize-1)*sizeof(struct r5dev)); | |
392 | ||
393 | nsh->raid_conf = conf; | |
394 | spin_lock_init(&nsh->lock); | |
395 | ||
396 | list_add(&nsh->lru, &newstripes); | |
397 | } | |
398 | if (i) { | |
399 | /* didn't get enough, give up */ | |
400 | while (!list_empty(&newstripes)) { | |
401 | nsh = list_entry(newstripes.next, struct stripe_head, lru); | |
402 | list_del(&nsh->lru); | |
403 | kmem_cache_free(sc, nsh); | |
404 | } | |
405 | kmem_cache_destroy(sc); | |
406 | return -ENOMEM; | |
407 | } | |
408 | /* Step 2 - Must use GFP_NOIO now. | |
409 | * OK, we have enough stripes, start collecting inactive | |
410 | * stripes and copying them over | |
411 | */ | |
412 | list_for_each_entry(nsh, &newstripes, lru) { | |
413 | spin_lock_irq(&conf->device_lock); | |
414 | wait_event_lock_irq(conf->wait_for_stripe, | |
415 | !list_empty(&conf->inactive_list), | |
416 | conf->device_lock, | |
b3b46be3 | 417 | unplug_slaves(conf->mddev) |
ad01c9e3 N |
418 | ); |
419 | osh = get_free_stripe(conf); | |
420 | spin_unlock_irq(&conf->device_lock); | |
421 | atomic_set(&nsh->count, 1); | |
422 | for(i=0; i<conf->pool_size; i++) | |
423 | nsh->dev[i].page = osh->dev[i].page; | |
424 | for( ; i<newsize; i++) | |
425 | nsh->dev[i].page = NULL; | |
426 | kmem_cache_free(conf->slab_cache, osh); | |
427 | } | |
428 | kmem_cache_destroy(conf->slab_cache); | |
429 | ||
430 | /* Step 3. | |
431 | * At this point, we are holding all the stripes so the array | |
432 | * is completely stalled, so now is a good time to resize | |
433 | * conf->disks. | |
434 | */ | |
435 | ndisks = kzalloc(newsize * sizeof(struct disk_info), GFP_NOIO); | |
436 | if (ndisks) { | |
437 | for (i=0; i<conf->raid_disks; i++) | |
438 | ndisks[i] = conf->disks[i]; | |
439 | kfree(conf->disks); | |
440 | conf->disks = ndisks; | |
441 | } else | |
442 | err = -ENOMEM; | |
443 | ||
444 | /* Step 4, return new stripes to service */ | |
445 | while(!list_empty(&newstripes)) { | |
446 | nsh = list_entry(newstripes.next, struct stripe_head, lru); | |
447 | list_del_init(&nsh->lru); | |
448 | for (i=conf->raid_disks; i < newsize; i++) | |
449 | if (nsh->dev[i].page == NULL) { | |
450 | struct page *p = alloc_page(GFP_NOIO); | |
451 | nsh->dev[i].page = p; | |
452 | if (!p) | |
453 | err = -ENOMEM; | |
454 | } | |
455 | release_stripe(nsh); | |
456 | } | |
457 | /* critical section pass, GFP_NOIO no longer needed */ | |
458 | ||
459 | conf->slab_cache = sc; | |
460 | conf->active_name = 1-conf->active_name; | |
461 | conf->pool_size = newsize; | |
462 | return err; | |
463 | } | |
29269553 | 464 | #endif |
1da177e4 | 465 | |
3f294f4f | 466 | static int drop_one_stripe(raid5_conf_t *conf) |
1da177e4 LT |
467 | { |
468 | struct stripe_head *sh; | |
469 | ||
3f294f4f N |
470 | spin_lock_irq(&conf->device_lock); |
471 | sh = get_free_stripe(conf); | |
472 | spin_unlock_irq(&conf->device_lock); | |
473 | if (!sh) | |
474 | return 0; | |
78bafebd | 475 | BUG_ON(atomic_read(&sh->count)); |
ad01c9e3 | 476 | shrink_buffers(sh, conf->pool_size); |
3f294f4f N |
477 | kmem_cache_free(conf->slab_cache, sh); |
478 | atomic_dec(&conf->active_stripes); | |
479 | return 1; | |
480 | } | |
481 | ||
482 | static void shrink_stripes(raid5_conf_t *conf) | |
483 | { | |
484 | while (drop_one_stripe(conf)) | |
485 | ; | |
486 | ||
29fc7e3e N |
487 | if (conf->slab_cache) |
488 | kmem_cache_destroy(conf->slab_cache); | |
1da177e4 LT |
489 | conf->slab_cache = NULL; |
490 | } | |
491 | ||
4e5314b5 | 492 | static int raid5_end_read_request(struct bio * bi, unsigned int bytes_done, |
1da177e4 LT |
493 | int error) |
494 | { | |
495 | struct stripe_head *sh = bi->bi_private; | |
496 | raid5_conf_t *conf = sh->raid_conf; | |
7ecaa1e6 | 497 | int disks = sh->disks, i; |
1da177e4 LT |
498 | int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags); |
499 | ||
500 | if (bi->bi_size) | |
501 | return 1; | |
502 | ||
503 | for (i=0 ; i<disks; i++) | |
504 | if (bi == &sh->dev[i].req) | |
505 | break; | |
506 | ||
507 | PRINTK("end_read_request %llu/%d, count: %d, uptodate %d.\n", | |
508 | (unsigned long long)sh->sector, i, atomic_read(&sh->count), | |
509 | uptodate); | |
510 | if (i == disks) { | |
511 | BUG(); | |
512 | return 0; | |
513 | } | |
514 | ||
515 | if (uptodate) { | |
516 | #if 0 | |
517 | struct bio *bio; | |
518 | unsigned long flags; | |
519 | spin_lock_irqsave(&conf->device_lock, flags); | |
520 | /* we can return a buffer if we bypassed the cache or | |
521 | * if the top buffer is not in highmem. If there are | |
522 | * multiple buffers, leave the extra work to | |
523 | * handle_stripe | |
524 | */ | |
525 | buffer = sh->bh_read[i]; | |
526 | if (buffer && | |
527 | (!PageHighMem(buffer->b_page) | |
528 | || buffer->b_page == bh->b_page ) | |
529 | ) { | |
530 | sh->bh_read[i] = buffer->b_reqnext; | |
531 | buffer->b_reqnext = NULL; | |
532 | } else | |
533 | buffer = NULL; | |
534 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
535 | if (sh->bh_page[i]==bh->b_page) | |
536 | set_buffer_uptodate(bh); | |
537 | if (buffer) { | |
538 | if (buffer->b_page != bh->b_page) | |
539 | memcpy(buffer->b_data, bh->b_data, bh->b_size); | |
540 | buffer->b_end_io(buffer, 1); | |
541 | } | |
542 | #else | |
543 | set_bit(R5_UPTODATE, &sh->dev[i].flags); | |
4e5314b5 N |
544 | #endif |
545 | if (test_bit(R5_ReadError, &sh->dev[i].flags)) { | |
14f8d26b | 546 | printk(KERN_INFO "raid5: read error corrected!!\n"); |
4e5314b5 N |
547 | clear_bit(R5_ReadError, &sh->dev[i].flags); |
548 | clear_bit(R5_ReWrite, &sh->dev[i].flags); | |
549 | } | |
ba22dcbf N |
550 | if (atomic_read(&conf->disks[i].rdev->read_errors)) |
551 | atomic_set(&conf->disks[i].rdev->read_errors, 0); | |
1da177e4 | 552 | } else { |
ba22dcbf | 553 | int retry = 0; |
1da177e4 | 554 | clear_bit(R5_UPTODATE, &sh->dev[i].flags); |
ba22dcbf N |
555 | atomic_inc(&conf->disks[i].rdev->read_errors); |
556 | if (conf->mddev->degraded) | |
14f8d26b | 557 | printk(KERN_WARNING "raid5: read error not correctable.\n"); |
ba22dcbf | 558 | else if (test_bit(R5_ReWrite, &sh->dev[i].flags)) |
4e5314b5 | 559 | /* Oh, no!!! */ |
14f8d26b | 560 | printk(KERN_WARNING "raid5: read error NOT corrected!!\n"); |
ba22dcbf N |
561 | else if (atomic_read(&conf->disks[i].rdev->read_errors) |
562 | > conf->max_nr_stripes) | |
14f8d26b N |
563 | printk(KERN_WARNING |
564 | "raid5: Too many read errors, failing device.\n"); | |
ba22dcbf N |
565 | else |
566 | retry = 1; | |
567 | if (retry) | |
568 | set_bit(R5_ReadError, &sh->dev[i].flags); | |
569 | else { | |
4e5314b5 N |
570 | clear_bit(R5_ReadError, &sh->dev[i].flags); |
571 | clear_bit(R5_ReWrite, &sh->dev[i].flags); | |
572 | md_error(conf->mddev, conf->disks[i].rdev); | |
ba22dcbf | 573 | } |
1da177e4 LT |
574 | } |
575 | rdev_dec_pending(conf->disks[i].rdev, conf->mddev); | |
576 | #if 0 | |
577 | /* must restore b_page before unlocking buffer... */ | |
578 | if (sh->bh_page[i] != bh->b_page) { | |
579 | bh->b_page = sh->bh_page[i]; | |
580 | bh->b_data = page_address(bh->b_page); | |
581 | clear_buffer_uptodate(bh); | |
582 | } | |
583 | #endif | |
584 | clear_bit(R5_LOCKED, &sh->dev[i].flags); | |
585 | set_bit(STRIPE_HANDLE, &sh->state); | |
586 | release_stripe(sh); | |
587 | return 0; | |
588 | } | |
589 | ||
590 | static int raid5_end_write_request (struct bio *bi, unsigned int bytes_done, | |
591 | int error) | |
592 | { | |
593 | struct stripe_head *sh = bi->bi_private; | |
594 | raid5_conf_t *conf = sh->raid_conf; | |
7ecaa1e6 | 595 | int disks = sh->disks, i; |
1da177e4 LT |
596 | unsigned long flags; |
597 | int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags); | |
598 | ||
599 | if (bi->bi_size) | |
600 | return 1; | |
601 | ||
602 | for (i=0 ; i<disks; i++) | |
603 | if (bi == &sh->dev[i].req) | |
604 | break; | |
605 | ||
606 | PRINTK("end_write_request %llu/%d, count %d, uptodate: %d.\n", | |
607 | (unsigned long long)sh->sector, i, atomic_read(&sh->count), | |
608 | uptodate); | |
609 | if (i == disks) { | |
610 | BUG(); | |
611 | return 0; | |
612 | } | |
613 | ||
614 | spin_lock_irqsave(&conf->device_lock, flags); | |
615 | if (!uptodate) | |
616 | md_error(conf->mddev, conf->disks[i].rdev); | |
617 | ||
618 | rdev_dec_pending(conf->disks[i].rdev, conf->mddev); | |
619 | ||
620 | clear_bit(R5_LOCKED, &sh->dev[i].flags); | |
621 | set_bit(STRIPE_HANDLE, &sh->state); | |
622 | __release_stripe(conf, sh); | |
623 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
624 | return 0; | |
625 | } | |
626 | ||
627 | ||
628 | static sector_t compute_blocknr(struct stripe_head *sh, int i); | |
629 | ||
630 | static void raid5_build_block (struct stripe_head *sh, int i) | |
631 | { | |
632 | struct r5dev *dev = &sh->dev[i]; | |
633 | ||
634 | bio_init(&dev->req); | |
635 | dev->req.bi_io_vec = &dev->vec; | |
636 | dev->req.bi_vcnt++; | |
637 | dev->req.bi_max_vecs++; | |
638 | dev->vec.bv_page = dev->page; | |
639 | dev->vec.bv_len = STRIPE_SIZE; | |
640 | dev->vec.bv_offset = 0; | |
641 | ||
642 | dev->req.bi_sector = sh->sector; | |
643 | dev->req.bi_private = sh; | |
644 | ||
645 | dev->flags = 0; | |
16a53ecc | 646 | dev->sector = compute_blocknr(sh, i); |
1da177e4 LT |
647 | } |
648 | ||
649 | static void error(mddev_t *mddev, mdk_rdev_t *rdev) | |
650 | { | |
651 | char b[BDEVNAME_SIZE]; | |
652 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; | |
653 | PRINTK("raid5: error called\n"); | |
654 | ||
b2d444d7 | 655 | if (!test_bit(Faulty, &rdev->flags)) { |
1da177e4 | 656 | mddev->sb_dirty = 1; |
b2d444d7 | 657 | if (test_bit(In_sync, &rdev->flags)) { |
1da177e4 LT |
658 | conf->working_disks--; |
659 | mddev->degraded++; | |
660 | conf->failed_disks++; | |
b2d444d7 | 661 | clear_bit(In_sync, &rdev->flags); |
1da177e4 LT |
662 | /* |
663 | * if recovery was running, make sure it aborts. | |
664 | */ | |
665 | set_bit(MD_RECOVERY_ERR, &mddev->recovery); | |
666 | } | |
b2d444d7 | 667 | set_bit(Faulty, &rdev->flags); |
1da177e4 LT |
668 | printk (KERN_ALERT |
669 | "raid5: Disk failure on %s, disabling device." | |
670 | " Operation continuing on %d devices\n", | |
671 | bdevname(rdev->bdev,b), conf->working_disks); | |
672 | } | |
16a53ecc | 673 | } |
1da177e4 LT |
674 | |
675 | /* | |
676 | * Input: a 'big' sector number, | |
677 | * Output: index of the data and parity disk, and the sector # in them. | |
678 | */ | |
679 | static sector_t raid5_compute_sector(sector_t r_sector, unsigned int raid_disks, | |
680 | unsigned int data_disks, unsigned int * dd_idx, | |
681 | unsigned int * pd_idx, raid5_conf_t *conf) | |
682 | { | |
683 | long stripe; | |
684 | unsigned long chunk_number; | |
685 | unsigned int chunk_offset; | |
686 | sector_t new_sector; | |
687 | int sectors_per_chunk = conf->chunk_size >> 9; | |
688 | ||
689 | /* First compute the information on this sector */ | |
690 | ||
691 | /* | |
692 | * Compute the chunk number and the sector offset inside the chunk | |
693 | */ | |
694 | chunk_offset = sector_div(r_sector, sectors_per_chunk); | |
695 | chunk_number = r_sector; | |
696 | BUG_ON(r_sector != chunk_number); | |
697 | ||
698 | /* | |
699 | * Compute the stripe number | |
700 | */ | |
701 | stripe = chunk_number / data_disks; | |
702 | ||
703 | /* | |
704 | * Compute the data disk and parity disk indexes inside the stripe | |
705 | */ | |
706 | *dd_idx = chunk_number % data_disks; | |
707 | ||
708 | /* | |
709 | * Select the parity disk based on the user selected algorithm. | |
710 | */ | |
16a53ecc N |
711 | switch(conf->level) { |
712 | case 4: | |
1da177e4 | 713 | *pd_idx = data_disks; |
16a53ecc N |
714 | break; |
715 | case 5: | |
716 | switch (conf->algorithm) { | |
1da177e4 LT |
717 | case ALGORITHM_LEFT_ASYMMETRIC: |
718 | *pd_idx = data_disks - stripe % raid_disks; | |
719 | if (*dd_idx >= *pd_idx) | |
720 | (*dd_idx)++; | |
721 | break; | |
722 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
723 | *pd_idx = stripe % raid_disks; | |
724 | if (*dd_idx >= *pd_idx) | |
725 | (*dd_idx)++; | |
726 | break; | |
727 | case ALGORITHM_LEFT_SYMMETRIC: | |
728 | *pd_idx = data_disks - stripe % raid_disks; | |
729 | *dd_idx = (*pd_idx + 1 + *dd_idx) % raid_disks; | |
730 | break; | |
731 | case ALGORITHM_RIGHT_SYMMETRIC: | |
732 | *pd_idx = stripe % raid_disks; | |
733 | *dd_idx = (*pd_idx + 1 + *dd_idx) % raid_disks; | |
734 | break; | |
735 | default: | |
14f8d26b | 736 | printk(KERN_ERR "raid5: unsupported algorithm %d\n", |
1da177e4 | 737 | conf->algorithm); |
16a53ecc N |
738 | } |
739 | break; | |
740 | case 6: | |
741 | ||
742 | /**** FIX THIS ****/ | |
743 | switch (conf->algorithm) { | |
744 | case ALGORITHM_LEFT_ASYMMETRIC: | |
745 | *pd_idx = raid_disks - 1 - (stripe % raid_disks); | |
746 | if (*pd_idx == raid_disks-1) | |
747 | (*dd_idx)++; /* Q D D D P */ | |
748 | else if (*dd_idx >= *pd_idx) | |
749 | (*dd_idx) += 2; /* D D P Q D */ | |
750 | break; | |
751 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
752 | *pd_idx = stripe % raid_disks; | |
753 | if (*pd_idx == raid_disks-1) | |
754 | (*dd_idx)++; /* Q D D D P */ | |
755 | else if (*dd_idx >= *pd_idx) | |
756 | (*dd_idx) += 2; /* D D P Q D */ | |
757 | break; | |
758 | case ALGORITHM_LEFT_SYMMETRIC: | |
759 | *pd_idx = raid_disks - 1 - (stripe % raid_disks); | |
760 | *dd_idx = (*pd_idx + 2 + *dd_idx) % raid_disks; | |
761 | break; | |
762 | case ALGORITHM_RIGHT_SYMMETRIC: | |
763 | *pd_idx = stripe % raid_disks; | |
764 | *dd_idx = (*pd_idx + 2 + *dd_idx) % raid_disks; | |
765 | break; | |
766 | default: | |
767 | printk (KERN_CRIT "raid6: unsupported algorithm %d\n", | |
768 | conf->algorithm); | |
769 | } | |
770 | break; | |
1da177e4 LT |
771 | } |
772 | ||
773 | /* | |
774 | * Finally, compute the new sector number | |
775 | */ | |
776 | new_sector = (sector_t)stripe * sectors_per_chunk + chunk_offset; | |
777 | return new_sector; | |
778 | } | |
779 | ||
780 | ||
781 | static sector_t compute_blocknr(struct stripe_head *sh, int i) | |
782 | { | |
783 | raid5_conf_t *conf = sh->raid_conf; | |
7ecaa1e6 | 784 | int raid_disks = sh->disks, data_disks = raid_disks - 1; |
1da177e4 LT |
785 | sector_t new_sector = sh->sector, check; |
786 | int sectors_per_chunk = conf->chunk_size >> 9; | |
787 | sector_t stripe; | |
788 | int chunk_offset; | |
789 | int chunk_number, dummy1, dummy2, dd_idx = i; | |
790 | sector_t r_sector; | |
791 | ||
16a53ecc | 792 | |
1da177e4 LT |
793 | chunk_offset = sector_div(new_sector, sectors_per_chunk); |
794 | stripe = new_sector; | |
795 | BUG_ON(new_sector != stripe); | |
796 | ||
16a53ecc N |
797 | if (i == sh->pd_idx) |
798 | return 0; | |
799 | switch(conf->level) { | |
800 | case 4: break; | |
801 | case 5: | |
802 | switch (conf->algorithm) { | |
1da177e4 LT |
803 | case ALGORITHM_LEFT_ASYMMETRIC: |
804 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
805 | if (i > sh->pd_idx) | |
806 | i--; | |
807 | break; | |
808 | case ALGORITHM_LEFT_SYMMETRIC: | |
809 | case ALGORITHM_RIGHT_SYMMETRIC: | |
810 | if (i < sh->pd_idx) | |
811 | i += raid_disks; | |
812 | i -= (sh->pd_idx + 1); | |
813 | break; | |
814 | default: | |
14f8d26b | 815 | printk(KERN_ERR "raid5: unsupported algorithm %d\n", |
16a53ecc N |
816 | conf->algorithm); |
817 | } | |
818 | break; | |
819 | case 6: | |
820 | data_disks = raid_disks - 2; | |
821 | if (i == raid6_next_disk(sh->pd_idx, raid_disks)) | |
822 | return 0; /* It is the Q disk */ | |
823 | switch (conf->algorithm) { | |
824 | case ALGORITHM_LEFT_ASYMMETRIC: | |
825 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
826 | if (sh->pd_idx == raid_disks-1) | |
827 | i--; /* Q D D D P */ | |
828 | else if (i > sh->pd_idx) | |
829 | i -= 2; /* D D P Q D */ | |
830 | break; | |
831 | case ALGORITHM_LEFT_SYMMETRIC: | |
832 | case ALGORITHM_RIGHT_SYMMETRIC: | |
833 | if (sh->pd_idx == raid_disks-1) | |
834 | i--; /* Q D D D P */ | |
835 | else { | |
836 | /* D D P Q D */ | |
837 | if (i < sh->pd_idx) | |
838 | i += raid_disks; | |
839 | i -= (sh->pd_idx + 2); | |
840 | } | |
841 | break; | |
842 | default: | |
843 | printk (KERN_CRIT "raid6: unsupported algorithm %d\n", | |
1da177e4 | 844 | conf->algorithm); |
16a53ecc N |
845 | } |
846 | break; | |
1da177e4 LT |
847 | } |
848 | ||
849 | chunk_number = stripe * data_disks + i; | |
850 | r_sector = (sector_t)chunk_number * sectors_per_chunk + chunk_offset; | |
851 | ||
852 | check = raid5_compute_sector (r_sector, raid_disks, data_disks, &dummy1, &dummy2, conf); | |
853 | if (check != sh->sector || dummy1 != dd_idx || dummy2 != sh->pd_idx) { | |
14f8d26b | 854 | printk(KERN_ERR "compute_blocknr: map not correct\n"); |
1da177e4 LT |
855 | return 0; |
856 | } | |
857 | return r_sector; | |
858 | } | |
859 | ||
860 | ||
861 | ||
862 | /* | |
16a53ecc N |
863 | * Copy data between a page in the stripe cache, and one or more bion |
864 | * The page could align with the middle of the bio, or there could be | |
865 | * several bion, each with several bio_vecs, which cover part of the page | |
866 | * Multiple bion are linked together on bi_next. There may be extras | |
867 | * at the end of this list. We ignore them. | |
1da177e4 LT |
868 | */ |
869 | static void copy_data(int frombio, struct bio *bio, | |
870 | struct page *page, | |
871 | sector_t sector) | |
872 | { | |
873 | char *pa = page_address(page); | |
874 | struct bio_vec *bvl; | |
875 | int i; | |
876 | int page_offset; | |
877 | ||
878 | if (bio->bi_sector >= sector) | |
879 | page_offset = (signed)(bio->bi_sector - sector) * 512; | |
880 | else | |
881 | page_offset = (signed)(sector - bio->bi_sector) * -512; | |
882 | bio_for_each_segment(bvl, bio, i) { | |
883 | int len = bio_iovec_idx(bio,i)->bv_len; | |
884 | int clen; | |
885 | int b_offset = 0; | |
886 | ||
887 | if (page_offset < 0) { | |
888 | b_offset = -page_offset; | |
889 | page_offset += b_offset; | |
890 | len -= b_offset; | |
891 | } | |
892 | ||
893 | if (len > 0 && page_offset + len > STRIPE_SIZE) | |
894 | clen = STRIPE_SIZE - page_offset; | |
895 | else clen = len; | |
16a53ecc | 896 | |
1da177e4 LT |
897 | if (clen > 0) { |
898 | char *ba = __bio_kmap_atomic(bio, i, KM_USER0); | |
899 | if (frombio) | |
900 | memcpy(pa+page_offset, ba+b_offset, clen); | |
901 | else | |
902 | memcpy(ba+b_offset, pa+page_offset, clen); | |
903 | __bio_kunmap_atomic(ba, KM_USER0); | |
904 | } | |
905 | if (clen < len) /* hit end of page */ | |
906 | break; | |
907 | page_offset += len; | |
908 | } | |
909 | } | |
910 | ||
911 | #define check_xor() do { \ | |
912 | if (count == MAX_XOR_BLOCKS) { \ | |
913 | xor_block(count, STRIPE_SIZE, ptr); \ | |
914 | count = 1; \ | |
915 | } \ | |
916 | } while(0) | |
917 | ||
918 | ||
919 | static void compute_block(struct stripe_head *sh, int dd_idx) | |
920 | { | |
7ecaa1e6 | 921 | int i, count, disks = sh->disks; |
1da177e4 LT |
922 | void *ptr[MAX_XOR_BLOCKS], *p; |
923 | ||
924 | PRINTK("compute_block, stripe %llu, idx %d\n", | |
925 | (unsigned long long)sh->sector, dd_idx); | |
926 | ||
927 | ptr[0] = page_address(sh->dev[dd_idx].page); | |
928 | memset(ptr[0], 0, STRIPE_SIZE); | |
929 | count = 1; | |
930 | for (i = disks ; i--; ) { | |
931 | if (i == dd_idx) | |
932 | continue; | |
933 | p = page_address(sh->dev[i].page); | |
934 | if (test_bit(R5_UPTODATE, &sh->dev[i].flags)) | |
935 | ptr[count++] = p; | |
936 | else | |
14f8d26b | 937 | printk(KERN_ERR "compute_block() %d, stripe %llu, %d" |
1da177e4 LT |
938 | " not present\n", dd_idx, |
939 | (unsigned long long)sh->sector, i); | |
940 | ||
941 | check_xor(); | |
942 | } | |
943 | if (count != 1) | |
944 | xor_block(count, STRIPE_SIZE, ptr); | |
945 | set_bit(R5_UPTODATE, &sh->dev[dd_idx].flags); | |
946 | } | |
947 | ||
16a53ecc | 948 | static void compute_parity5(struct stripe_head *sh, int method) |
1da177e4 LT |
949 | { |
950 | raid5_conf_t *conf = sh->raid_conf; | |
7ecaa1e6 | 951 | int i, pd_idx = sh->pd_idx, disks = sh->disks, count; |
1da177e4 LT |
952 | void *ptr[MAX_XOR_BLOCKS]; |
953 | struct bio *chosen; | |
954 | ||
16a53ecc | 955 | PRINTK("compute_parity5, stripe %llu, method %d\n", |
1da177e4 LT |
956 | (unsigned long long)sh->sector, method); |
957 | ||
958 | count = 1; | |
959 | ptr[0] = page_address(sh->dev[pd_idx].page); | |
960 | switch(method) { | |
961 | case READ_MODIFY_WRITE: | |
78bafebd | 962 | BUG_ON(!test_bit(R5_UPTODATE, &sh->dev[pd_idx].flags)); |
1da177e4 LT |
963 | for (i=disks ; i-- ;) { |
964 | if (i==pd_idx) | |
965 | continue; | |
966 | if (sh->dev[i].towrite && | |
967 | test_bit(R5_UPTODATE, &sh->dev[i].flags)) { | |
968 | ptr[count++] = page_address(sh->dev[i].page); | |
969 | chosen = sh->dev[i].towrite; | |
970 | sh->dev[i].towrite = NULL; | |
971 | ||
972 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) | |
973 | wake_up(&conf->wait_for_overlap); | |
974 | ||
78bafebd | 975 | BUG_ON(sh->dev[i].written); |
1da177e4 LT |
976 | sh->dev[i].written = chosen; |
977 | check_xor(); | |
978 | } | |
979 | } | |
980 | break; | |
981 | case RECONSTRUCT_WRITE: | |
982 | memset(ptr[0], 0, STRIPE_SIZE); | |
983 | for (i= disks; i-- ;) | |
984 | if (i!=pd_idx && sh->dev[i].towrite) { | |
985 | chosen = sh->dev[i].towrite; | |
986 | sh->dev[i].towrite = NULL; | |
987 | ||
988 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) | |
989 | wake_up(&conf->wait_for_overlap); | |
990 | ||
78bafebd | 991 | BUG_ON(sh->dev[i].written); |
1da177e4 LT |
992 | sh->dev[i].written = chosen; |
993 | } | |
994 | break; | |
995 | case CHECK_PARITY: | |
996 | break; | |
997 | } | |
998 | if (count>1) { | |
999 | xor_block(count, STRIPE_SIZE, ptr); | |
1000 | count = 1; | |
1001 | } | |
1002 | ||
1003 | for (i = disks; i--;) | |
1004 | if (sh->dev[i].written) { | |
1005 | sector_t sector = sh->dev[i].sector; | |
1006 | struct bio *wbi = sh->dev[i].written; | |
1007 | while (wbi && wbi->bi_sector < sector + STRIPE_SECTORS) { | |
1008 | copy_data(1, wbi, sh->dev[i].page, sector); | |
1009 | wbi = r5_next_bio(wbi, sector); | |
1010 | } | |
1011 | ||
1012 | set_bit(R5_LOCKED, &sh->dev[i].flags); | |
1013 | set_bit(R5_UPTODATE, &sh->dev[i].flags); | |
1014 | } | |
1015 | ||
1016 | switch(method) { | |
1017 | case RECONSTRUCT_WRITE: | |
1018 | case CHECK_PARITY: | |
1019 | for (i=disks; i--;) | |
1020 | if (i != pd_idx) { | |
1021 | ptr[count++] = page_address(sh->dev[i].page); | |
1022 | check_xor(); | |
1023 | } | |
1024 | break; | |
1025 | case READ_MODIFY_WRITE: | |
1026 | for (i = disks; i--;) | |
1027 | if (sh->dev[i].written) { | |
1028 | ptr[count++] = page_address(sh->dev[i].page); | |
1029 | check_xor(); | |
1030 | } | |
1031 | } | |
1032 | if (count != 1) | |
1033 | xor_block(count, STRIPE_SIZE, ptr); | |
1034 | ||
1035 | if (method != CHECK_PARITY) { | |
1036 | set_bit(R5_UPTODATE, &sh->dev[pd_idx].flags); | |
1037 | set_bit(R5_LOCKED, &sh->dev[pd_idx].flags); | |
1038 | } else | |
1039 | clear_bit(R5_UPTODATE, &sh->dev[pd_idx].flags); | |
1040 | } | |
1041 | ||
16a53ecc N |
1042 | static void compute_parity6(struct stripe_head *sh, int method) |
1043 | { | |
1044 | raid6_conf_t *conf = sh->raid_conf; | |
1045 | int i, pd_idx = sh->pd_idx, qd_idx, d0_idx, disks = conf->raid_disks, count; | |
1046 | struct bio *chosen; | |
1047 | /**** FIX THIS: This could be very bad if disks is close to 256 ****/ | |
1048 | void *ptrs[disks]; | |
1049 | ||
1050 | qd_idx = raid6_next_disk(pd_idx, disks); | |
1051 | d0_idx = raid6_next_disk(qd_idx, disks); | |
1052 | ||
1053 | PRINTK("compute_parity, stripe %llu, method %d\n", | |
1054 | (unsigned long long)sh->sector, method); | |
1055 | ||
1056 | switch(method) { | |
1057 | case READ_MODIFY_WRITE: | |
1058 | BUG(); /* READ_MODIFY_WRITE N/A for RAID-6 */ | |
1059 | case RECONSTRUCT_WRITE: | |
1060 | for (i= disks; i-- ;) | |
1061 | if ( i != pd_idx && i != qd_idx && sh->dev[i].towrite ) { | |
1062 | chosen = sh->dev[i].towrite; | |
1063 | sh->dev[i].towrite = NULL; | |
1064 | ||
1065 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) | |
1066 | wake_up(&conf->wait_for_overlap); | |
1067 | ||
1068 | if (sh->dev[i].written) BUG(); | |
1069 | sh->dev[i].written = chosen; | |
1070 | } | |
1071 | break; | |
1072 | case CHECK_PARITY: | |
1073 | BUG(); /* Not implemented yet */ | |
1074 | } | |
1075 | ||
1076 | for (i = disks; i--;) | |
1077 | if (sh->dev[i].written) { | |
1078 | sector_t sector = sh->dev[i].sector; | |
1079 | struct bio *wbi = sh->dev[i].written; | |
1080 | while (wbi && wbi->bi_sector < sector + STRIPE_SECTORS) { | |
1081 | copy_data(1, wbi, sh->dev[i].page, sector); | |
1082 | wbi = r5_next_bio(wbi, sector); | |
1083 | } | |
1084 | ||
1085 | set_bit(R5_LOCKED, &sh->dev[i].flags); | |
1086 | set_bit(R5_UPTODATE, &sh->dev[i].flags); | |
1087 | } | |
1088 | ||
1089 | // switch(method) { | |
1090 | // case RECONSTRUCT_WRITE: | |
1091 | // case CHECK_PARITY: | |
1092 | // case UPDATE_PARITY: | |
1093 | /* Note that unlike RAID-5, the ordering of the disks matters greatly. */ | |
1094 | /* FIX: Is this ordering of drives even remotely optimal? */ | |
1095 | count = 0; | |
1096 | i = d0_idx; | |
1097 | do { | |
1098 | ptrs[count++] = page_address(sh->dev[i].page); | |
1099 | if (count <= disks-2 && !test_bit(R5_UPTODATE, &sh->dev[i].flags)) | |
1100 | printk("block %d/%d not uptodate on parity calc\n", i,count); | |
1101 | i = raid6_next_disk(i, disks); | |
1102 | } while ( i != d0_idx ); | |
1103 | // break; | |
1104 | // } | |
1105 | ||
1106 | raid6_call.gen_syndrome(disks, STRIPE_SIZE, ptrs); | |
1107 | ||
1108 | switch(method) { | |
1109 | case RECONSTRUCT_WRITE: | |
1110 | set_bit(R5_UPTODATE, &sh->dev[pd_idx].flags); | |
1111 | set_bit(R5_UPTODATE, &sh->dev[qd_idx].flags); | |
1112 | set_bit(R5_LOCKED, &sh->dev[pd_idx].flags); | |
1113 | set_bit(R5_LOCKED, &sh->dev[qd_idx].flags); | |
1114 | break; | |
1115 | case UPDATE_PARITY: | |
1116 | set_bit(R5_UPTODATE, &sh->dev[pd_idx].flags); | |
1117 | set_bit(R5_UPTODATE, &sh->dev[qd_idx].flags); | |
1118 | break; | |
1119 | } | |
1120 | } | |
1121 | ||
1122 | ||
1123 | /* Compute one missing block */ | |
1124 | static void compute_block_1(struct stripe_head *sh, int dd_idx, int nozero) | |
1125 | { | |
1126 | raid6_conf_t *conf = sh->raid_conf; | |
1127 | int i, count, disks = conf->raid_disks; | |
1128 | void *ptr[MAX_XOR_BLOCKS], *p; | |
1129 | int pd_idx = sh->pd_idx; | |
1130 | int qd_idx = raid6_next_disk(pd_idx, disks); | |
1131 | ||
1132 | PRINTK("compute_block_1, stripe %llu, idx %d\n", | |
1133 | (unsigned long long)sh->sector, dd_idx); | |
1134 | ||
1135 | if ( dd_idx == qd_idx ) { | |
1136 | /* We're actually computing the Q drive */ | |
1137 | compute_parity6(sh, UPDATE_PARITY); | |
1138 | } else { | |
1139 | ptr[0] = page_address(sh->dev[dd_idx].page); | |
1140 | if (!nozero) memset(ptr[0], 0, STRIPE_SIZE); | |
1141 | count = 1; | |
1142 | for (i = disks ; i--; ) { | |
1143 | if (i == dd_idx || i == qd_idx) | |
1144 | continue; | |
1145 | p = page_address(sh->dev[i].page); | |
1146 | if (test_bit(R5_UPTODATE, &sh->dev[i].flags)) | |
1147 | ptr[count++] = p; | |
1148 | else | |
1149 | printk("compute_block() %d, stripe %llu, %d" | |
1150 | " not present\n", dd_idx, | |
1151 | (unsigned long long)sh->sector, i); | |
1152 | ||
1153 | check_xor(); | |
1154 | } | |
1155 | if (count != 1) | |
1156 | xor_block(count, STRIPE_SIZE, ptr); | |
1157 | if (!nozero) set_bit(R5_UPTODATE, &sh->dev[dd_idx].flags); | |
1158 | else clear_bit(R5_UPTODATE, &sh->dev[dd_idx].flags); | |
1159 | } | |
1160 | } | |
1161 | ||
1162 | /* Compute two missing blocks */ | |
1163 | static void compute_block_2(struct stripe_head *sh, int dd_idx1, int dd_idx2) | |
1164 | { | |
1165 | raid6_conf_t *conf = sh->raid_conf; | |
1166 | int i, count, disks = conf->raid_disks; | |
1167 | int pd_idx = sh->pd_idx; | |
1168 | int qd_idx = raid6_next_disk(pd_idx, disks); | |
1169 | int d0_idx = raid6_next_disk(qd_idx, disks); | |
1170 | int faila, failb; | |
1171 | ||
1172 | /* faila and failb are disk numbers relative to d0_idx */ | |
1173 | /* pd_idx become disks-2 and qd_idx become disks-1 */ | |
1174 | faila = (dd_idx1 < d0_idx) ? dd_idx1+(disks-d0_idx) : dd_idx1-d0_idx; | |
1175 | failb = (dd_idx2 < d0_idx) ? dd_idx2+(disks-d0_idx) : dd_idx2-d0_idx; | |
1176 | ||
1177 | BUG_ON(faila == failb); | |
1178 | if ( failb < faila ) { int tmp = faila; faila = failb; failb = tmp; } | |
1179 | ||
1180 | PRINTK("compute_block_2, stripe %llu, idx %d,%d (%d,%d)\n", | |
1181 | (unsigned long long)sh->sector, dd_idx1, dd_idx2, faila, failb); | |
1182 | ||
1183 | if ( failb == disks-1 ) { | |
1184 | /* Q disk is one of the missing disks */ | |
1185 | if ( faila == disks-2 ) { | |
1186 | /* Missing P+Q, just recompute */ | |
1187 | compute_parity6(sh, UPDATE_PARITY); | |
1188 | return; | |
1189 | } else { | |
1190 | /* We're missing D+Q; recompute D from P */ | |
1191 | compute_block_1(sh, (dd_idx1 == qd_idx) ? dd_idx2 : dd_idx1, 0); | |
1192 | compute_parity6(sh, UPDATE_PARITY); /* Is this necessary? */ | |
1193 | return; | |
1194 | } | |
1195 | } | |
1196 | ||
1197 | /* We're missing D+P or D+D; build pointer table */ | |
1198 | { | |
1199 | /**** FIX THIS: This could be very bad if disks is close to 256 ****/ | |
1200 | void *ptrs[disks]; | |
1201 | ||
1202 | count = 0; | |
1203 | i = d0_idx; | |
1204 | do { | |
1205 | ptrs[count++] = page_address(sh->dev[i].page); | |
1206 | i = raid6_next_disk(i, disks); | |
1207 | if (i != dd_idx1 && i != dd_idx2 && | |
1208 | !test_bit(R5_UPTODATE, &sh->dev[i].flags)) | |
1209 | printk("compute_2 with missing block %d/%d\n", count, i); | |
1210 | } while ( i != d0_idx ); | |
1211 | ||
1212 | if ( failb == disks-2 ) { | |
1213 | /* We're missing D+P. */ | |
1214 | raid6_datap_recov(disks, STRIPE_SIZE, faila, ptrs); | |
1215 | } else { | |
1216 | /* We're missing D+D. */ | |
1217 | raid6_2data_recov(disks, STRIPE_SIZE, faila, failb, ptrs); | |
1218 | } | |
1219 | ||
1220 | /* Both the above update both missing blocks */ | |
1221 | set_bit(R5_UPTODATE, &sh->dev[dd_idx1].flags); | |
1222 | set_bit(R5_UPTODATE, &sh->dev[dd_idx2].flags); | |
1223 | } | |
1224 | } | |
1225 | ||
1226 | ||
1227 | ||
1da177e4 LT |
1228 | /* |
1229 | * Each stripe/dev can have one or more bion attached. | |
16a53ecc | 1230 | * toread/towrite point to the first in a chain. |
1da177e4 LT |
1231 | * The bi_next chain must be in order. |
1232 | */ | |
1233 | static int add_stripe_bio(struct stripe_head *sh, struct bio *bi, int dd_idx, int forwrite) | |
1234 | { | |
1235 | struct bio **bip; | |
1236 | raid5_conf_t *conf = sh->raid_conf; | |
72626685 | 1237 | int firstwrite=0; |
1da177e4 LT |
1238 | |
1239 | PRINTK("adding bh b#%llu to stripe s#%llu\n", | |
1240 | (unsigned long long)bi->bi_sector, | |
1241 | (unsigned long long)sh->sector); | |
1242 | ||
1243 | ||
1244 | spin_lock(&sh->lock); | |
1245 | spin_lock_irq(&conf->device_lock); | |
72626685 | 1246 | if (forwrite) { |
1da177e4 | 1247 | bip = &sh->dev[dd_idx].towrite; |
72626685 N |
1248 | if (*bip == NULL && sh->dev[dd_idx].written == NULL) |
1249 | firstwrite = 1; | |
1250 | } else | |
1da177e4 LT |
1251 | bip = &sh->dev[dd_idx].toread; |
1252 | while (*bip && (*bip)->bi_sector < bi->bi_sector) { | |
1253 | if ((*bip)->bi_sector + ((*bip)->bi_size >> 9) > bi->bi_sector) | |
1254 | goto overlap; | |
1255 | bip = & (*bip)->bi_next; | |
1256 | } | |
1257 | if (*bip && (*bip)->bi_sector < bi->bi_sector + ((bi->bi_size)>>9)) | |
1258 | goto overlap; | |
1259 | ||
78bafebd | 1260 | BUG_ON(*bip && bi->bi_next && (*bip) != bi->bi_next); |
1da177e4 LT |
1261 | if (*bip) |
1262 | bi->bi_next = *bip; | |
1263 | *bip = bi; | |
1264 | bi->bi_phys_segments ++; | |
1265 | spin_unlock_irq(&conf->device_lock); | |
1266 | spin_unlock(&sh->lock); | |
1267 | ||
1268 | PRINTK("added bi b#%llu to stripe s#%llu, disk %d.\n", | |
1269 | (unsigned long long)bi->bi_sector, | |
1270 | (unsigned long long)sh->sector, dd_idx); | |
1271 | ||
72626685 N |
1272 | if (conf->mddev->bitmap && firstwrite) { |
1273 | sh->bm_seq = conf->seq_write; | |
1274 | bitmap_startwrite(conf->mddev->bitmap, sh->sector, | |
1275 | STRIPE_SECTORS, 0); | |
1276 | set_bit(STRIPE_BIT_DELAY, &sh->state); | |
1277 | } | |
1278 | ||
1da177e4 LT |
1279 | if (forwrite) { |
1280 | /* check if page is covered */ | |
1281 | sector_t sector = sh->dev[dd_idx].sector; | |
1282 | for (bi=sh->dev[dd_idx].towrite; | |
1283 | sector < sh->dev[dd_idx].sector + STRIPE_SECTORS && | |
1284 | bi && bi->bi_sector <= sector; | |
1285 | bi = r5_next_bio(bi, sh->dev[dd_idx].sector)) { | |
1286 | if (bi->bi_sector + (bi->bi_size>>9) >= sector) | |
1287 | sector = bi->bi_sector + (bi->bi_size>>9); | |
1288 | } | |
1289 | if (sector >= sh->dev[dd_idx].sector + STRIPE_SECTORS) | |
1290 | set_bit(R5_OVERWRITE, &sh->dev[dd_idx].flags); | |
1291 | } | |
1292 | return 1; | |
1293 | ||
1294 | overlap: | |
1295 | set_bit(R5_Overlap, &sh->dev[dd_idx].flags); | |
1296 | spin_unlock_irq(&conf->device_lock); | |
1297 | spin_unlock(&sh->lock); | |
1298 | return 0; | |
1299 | } | |
1300 | ||
29269553 N |
1301 | static void end_reshape(raid5_conf_t *conf); |
1302 | ||
16a53ecc N |
1303 | static int page_is_zero(struct page *p) |
1304 | { | |
1305 | char *a = page_address(p); | |
1306 | return ((*(u32*)a) == 0 && | |
1307 | memcmp(a, a+4, STRIPE_SIZE-4)==0); | |
1308 | } | |
1309 | ||
ccfcc3c1 N |
1310 | static int stripe_to_pdidx(sector_t stripe, raid5_conf_t *conf, int disks) |
1311 | { | |
1312 | int sectors_per_chunk = conf->chunk_size >> 9; | |
1313 | sector_t x = stripe; | |
1314 | int pd_idx, dd_idx; | |
1315 | int chunk_offset = sector_div(x, sectors_per_chunk); | |
1316 | stripe = x; | |
1317 | raid5_compute_sector(stripe*(disks-1)*sectors_per_chunk | |
1318 | + chunk_offset, disks, disks-1, &dd_idx, &pd_idx, conf); | |
1319 | return pd_idx; | |
1320 | } | |
1321 | ||
1da177e4 LT |
1322 | |
1323 | /* | |
1324 | * handle_stripe - do things to a stripe. | |
1325 | * | |
1326 | * We lock the stripe and then examine the state of various bits | |
1327 | * to see what needs to be done. | |
1328 | * Possible results: | |
1329 | * return some read request which now have data | |
1330 | * return some write requests which are safely on disc | |
1331 | * schedule a read on some buffers | |
1332 | * schedule a write of some buffers | |
1333 | * return confirmation of parity correctness | |
1334 | * | |
1335 | * Parity calculations are done inside the stripe lock | |
1336 | * buffers are taken off read_list or write_list, and bh_cache buffers | |
1337 | * get BH_Lock set before the stripe lock is released. | |
1338 | * | |
1339 | */ | |
1340 | ||
16a53ecc | 1341 | static void handle_stripe5(struct stripe_head *sh) |
1da177e4 LT |
1342 | { |
1343 | raid5_conf_t *conf = sh->raid_conf; | |
7ecaa1e6 | 1344 | int disks = sh->disks; |
1da177e4 LT |
1345 | struct bio *return_bi= NULL; |
1346 | struct bio *bi; | |
1347 | int i; | |
ccfcc3c1 | 1348 | int syncing, expanding, expanded; |
1da177e4 LT |
1349 | int locked=0, uptodate=0, to_read=0, to_write=0, failed=0, written=0; |
1350 | int non_overwrite = 0; | |
1351 | int failed_num=0; | |
1352 | struct r5dev *dev; | |
1353 | ||
1354 | PRINTK("handling stripe %llu, cnt=%d, pd_idx=%d\n", | |
1355 | (unsigned long long)sh->sector, atomic_read(&sh->count), | |
1356 | sh->pd_idx); | |
1357 | ||
1358 | spin_lock(&sh->lock); | |
1359 | clear_bit(STRIPE_HANDLE, &sh->state); | |
1360 | clear_bit(STRIPE_DELAYED, &sh->state); | |
1361 | ||
1362 | syncing = test_bit(STRIPE_SYNCING, &sh->state); | |
ccfcc3c1 N |
1363 | expanding = test_bit(STRIPE_EXPAND_SOURCE, &sh->state); |
1364 | expanded = test_bit(STRIPE_EXPAND_READY, &sh->state); | |
1da177e4 LT |
1365 | /* Now to look around and see what can be done */ |
1366 | ||
9910f16a | 1367 | rcu_read_lock(); |
1da177e4 LT |
1368 | for (i=disks; i--; ) { |
1369 | mdk_rdev_t *rdev; | |
1370 | dev = &sh->dev[i]; | |
1371 | clear_bit(R5_Insync, &dev->flags); | |
1da177e4 LT |
1372 | |
1373 | PRINTK("check %d: state 0x%lx read %p write %p written %p\n", | |
1374 | i, dev->flags, dev->toread, dev->towrite, dev->written); | |
1375 | /* maybe we can reply to a read */ | |
1376 | if (test_bit(R5_UPTODATE, &dev->flags) && dev->toread) { | |
1377 | struct bio *rbi, *rbi2; | |
1378 | PRINTK("Return read for disc %d\n", i); | |
1379 | spin_lock_irq(&conf->device_lock); | |
1380 | rbi = dev->toread; | |
1381 | dev->toread = NULL; | |
1382 | if (test_and_clear_bit(R5_Overlap, &dev->flags)) | |
1383 | wake_up(&conf->wait_for_overlap); | |
1384 | spin_unlock_irq(&conf->device_lock); | |
1385 | while (rbi && rbi->bi_sector < dev->sector + STRIPE_SECTORS) { | |
1386 | copy_data(0, rbi, dev->page, dev->sector); | |
1387 | rbi2 = r5_next_bio(rbi, dev->sector); | |
1388 | spin_lock_irq(&conf->device_lock); | |
1389 | if (--rbi->bi_phys_segments == 0) { | |
1390 | rbi->bi_next = return_bi; | |
1391 | return_bi = rbi; | |
1392 | } | |
1393 | spin_unlock_irq(&conf->device_lock); | |
1394 | rbi = rbi2; | |
1395 | } | |
1396 | } | |
1397 | ||
1398 | /* now count some things */ | |
1399 | if (test_bit(R5_LOCKED, &dev->flags)) locked++; | |
1400 | if (test_bit(R5_UPTODATE, &dev->flags)) uptodate++; | |
1401 | ||
1402 | ||
1403 | if (dev->toread) to_read++; | |
1404 | if (dev->towrite) { | |
1405 | to_write++; | |
1406 | if (!test_bit(R5_OVERWRITE, &dev->flags)) | |
1407 | non_overwrite++; | |
1408 | } | |
1409 | if (dev->written) written++; | |
9910f16a | 1410 | rdev = rcu_dereference(conf->disks[i].rdev); |
b2d444d7 | 1411 | if (!rdev || !test_bit(In_sync, &rdev->flags)) { |
14f8d26b | 1412 | /* The ReadError flag will just be confusing now */ |
4e5314b5 N |
1413 | clear_bit(R5_ReadError, &dev->flags); |
1414 | clear_bit(R5_ReWrite, &dev->flags); | |
1415 | } | |
b2d444d7 | 1416 | if (!rdev || !test_bit(In_sync, &rdev->flags) |
4e5314b5 | 1417 | || test_bit(R5_ReadError, &dev->flags)) { |
1da177e4 LT |
1418 | failed++; |
1419 | failed_num = i; | |
1420 | } else | |
1421 | set_bit(R5_Insync, &dev->flags); | |
1422 | } | |
9910f16a | 1423 | rcu_read_unlock(); |
1da177e4 LT |
1424 | PRINTK("locked=%d uptodate=%d to_read=%d" |
1425 | " to_write=%d failed=%d failed_num=%d\n", | |
1426 | locked, uptodate, to_read, to_write, failed, failed_num); | |
1427 | /* check if the array has lost two devices and, if so, some requests might | |
1428 | * need to be failed | |
1429 | */ | |
1430 | if (failed > 1 && to_read+to_write+written) { | |
1da177e4 | 1431 | for (i=disks; i--; ) { |
72626685 | 1432 | int bitmap_end = 0; |
4e5314b5 N |
1433 | |
1434 | if (test_bit(R5_ReadError, &sh->dev[i].flags)) { | |
9910f16a N |
1435 | mdk_rdev_t *rdev; |
1436 | rcu_read_lock(); | |
1437 | rdev = rcu_dereference(conf->disks[i].rdev); | |
b2d444d7 | 1438 | if (rdev && test_bit(In_sync, &rdev->flags)) |
4e5314b5 N |
1439 | /* multiple read failures in one stripe */ |
1440 | md_error(conf->mddev, rdev); | |
9910f16a | 1441 | rcu_read_unlock(); |
4e5314b5 N |
1442 | } |
1443 | ||
72626685 | 1444 | spin_lock_irq(&conf->device_lock); |
1da177e4 LT |
1445 | /* fail all writes first */ |
1446 | bi = sh->dev[i].towrite; | |
1447 | sh->dev[i].towrite = NULL; | |
72626685 | 1448 | if (bi) { to_write--; bitmap_end = 1; } |
1da177e4 LT |
1449 | |
1450 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) | |
1451 | wake_up(&conf->wait_for_overlap); | |
1452 | ||
1453 | while (bi && bi->bi_sector < sh->dev[i].sector + STRIPE_SECTORS){ | |
1454 | struct bio *nextbi = r5_next_bio(bi, sh->dev[i].sector); | |
1455 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
1456 | if (--bi->bi_phys_segments == 0) { | |
1457 | md_write_end(conf->mddev); | |
1458 | bi->bi_next = return_bi; | |
1459 | return_bi = bi; | |
1460 | } | |
1461 | bi = nextbi; | |
1462 | } | |
1463 | /* and fail all 'written' */ | |
1464 | bi = sh->dev[i].written; | |
1465 | sh->dev[i].written = NULL; | |
72626685 | 1466 | if (bi) bitmap_end = 1; |
1da177e4 LT |
1467 | while (bi && bi->bi_sector < sh->dev[i].sector + STRIPE_SECTORS) { |
1468 | struct bio *bi2 = r5_next_bio(bi, sh->dev[i].sector); | |
1469 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
1470 | if (--bi->bi_phys_segments == 0) { | |
1471 | md_write_end(conf->mddev); | |
1472 | bi->bi_next = return_bi; | |
1473 | return_bi = bi; | |
1474 | } | |
1475 | bi = bi2; | |
1476 | } | |
1477 | ||
1478 | /* fail any reads if this device is non-operational */ | |
4e5314b5 N |
1479 | if (!test_bit(R5_Insync, &sh->dev[i].flags) || |
1480 | test_bit(R5_ReadError, &sh->dev[i].flags)) { | |
1da177e4 LT |
1481 | bi = sh->dev[i].toread; |
1482 | sh->dev[i].toread = NULL; | |
1483 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) | |
1484 | wake_up(&conf->wait_for_overlap); | |
1485 | if (bi) to_read--; | |
1486 | while (bi && bi->bi_sector < sh->dev[i].sector + STRIPE_SECTORS){ | |
1487 | struct bio *nextbi = r5_next_bio(bi, sh->dev[i].sector); | |
1488 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
1489 | if (--bi->bi_phys_segments == 0) { | |
1490 | bi->bi_next = return_bi; | |
1491 | return_bi = bi; | |
1492 | } | |
1493 | bi = nextbi; | |
1494 | } | |
1495 | } | |
72626685 N |
1496 | spin_unlock_irq(&conf->device_lock); |
1497 | if (bitmap_end) | |
1498 | bitmap_endwrite(conf->mddev->bitmap, sh->sector, | |
1499 | STRIPE_SECTORS, 0, 0); | |
1da177e4 | 1500 | } |
1da177e4 LT |
1501 | } |
1502 | if (failed > 1 && syncing) { | |
1503 | md_done_sync(conf->mddev, STRIPE_SECTORS,0); | |
1504 | clear_bit(STRIPE_SYNCING, &sh->state); | |
1505 | syncing = 0; | |
1506 | } | |
1507 | ||
1508 | /* might be able to return some write requests if the parity block | |
1509 | * is safe, or on a failed drive | |
1510 | */ | |
1511 | dev = &sh->dev[sh->pd_idx]; | |
1512 | if ( written && | |
1513 | ( (test_bit(R5_Insync, &dev->flags) && !test_bit(R5_LOCKED, &dev->flags) && | |
1514 | test_bit(R5_UPTODATE, &dev->flags)) | |
1515 | || (failed == 1 && failed_num == sh->pd_idx)) | |
1516 | ) { | |
1517 | /* any written block on an uptodate or failed drive can be returned. | |
1518 | * Note that if we 'wrote' to a failed drive, it will be UPTODATE, but | |
1519 | * never LOCKED, so we don't need to test 'failed' directly. | |
1520 | */ | |
1521 | for (i=disks; i--; ) | |
1522 | if (sh->dev[i].written) { | |
1523 | dev = &sh->dev[i]; | |
1524 | if (!test_bit(R5_LOCKED, &dev->flags) && | |
1525 | test_bit(R5_UPTODATE, &dev->flags) ) { | |
1526 | /* We can return any write requests */ | |
1527 | struct bio *wbi, *wbi2; | |
72626685 | 1528 | int bitmap_end = 0; |
1da177e4 LT |
1529 | PRINTK("Return write for disc %d\n", i); |
1530 | spin_lock_irq(&conf->device_lock); | |
1531 | wbi = dev->written; | |
1532 | dev->written = NULL; | |
1533 | while (wbi && wbi->bi_sector < dev->sector + STRIPE_SECTORS) { | |
1534 | wbi2 = r5_next_bio(wbi, dev->sector); | |
1535 | if (--wbi->bi_phys_segments == 0) { | |
1536 | md_write_end(conf->mddev); | |
1537 | wbi->bi_next = return_bi; | |
1538 | return_bi = wbi; | |
1539 | } | |
1540 | wbi = wbi2; | |
1541 | } | |
72626685 N |
1542 | if (dev->towrite == NULL) |
1543 | bitmap_end = 1; | |
1da177e4 | 1544 | spin_unlock_irq(&conf->device_lock); |
72626685 N |
1545 | if (bitmap_end) |
1546 | bitmap_endwrite(conf->mddev->bitmap, sh->sector, | |
1547 | STRIPE_SECTORS, | |
1548 | !test_bit(STRIPE_DEGRADED, &sh->state), 0); | |
1da177e4 LT |
1549 | } |
1550 | } | |
1551 | } | |
1552 | ||
1553 | /* Now we might consider reading some blocks, either to check/generate | |
1554 | * parity, or to satisfy requests | |
1555 | * or to load a block that is being partially written. | |
1556 | */ | |
ccfcc3c1 | 1557 | if (to_read || non_overwrite || (syncing && (uptodate < disks)) || expanding) { |
1da177e4 LT |
1558 | for (i=disks; i--;) { |
1559 | dev = &sh->dev[i]; | |
1560 | if (!test_bit(R5_LOCKED, &dev->flags) && !test_bit(R5_UPTODATE, &dev->flags) && | |
1561 | (dev->toread || | |
1562 | (dev->towrite && !test_bit(R5_OVERWRITE, &dev->flags)) || | |
1563 | syncing || | |
ccfcc3c1 | 1564 | expanding || |
1da177e4 LT |
1565 | (failed && (sh->dev[failed_num].toread || |
1566 | (sh->dev[failed_num].towrite && !test_bit(R5_OVERWRITE, &sh->dev[failed_num].flags)))) | |
1567 | ) | |
1568 | ) { | |
1569 | /* we would like to get this block, possibly | |
1570 | * by computing it, but we might not be able to | |
1571 | */ | |
1572 | if (uptodate == disks-1) { | |
1573 | PRINTK("Computing block %d\n", i); | |
1574 | compute_block(sh, i); | |
1575 | uptodate++; | |
1576 | } else if (test_bit(R5_Insync, &dev->flags)) { | |
1577 | set_bit(R5_LOCKED, &dev->flags); | |
1578 | set_bit(R5_Wantread, &dev->flags); | |
1579 | #if 0 | |
1580 | /* if I am just reading this block and we don't have | |
1581 | a failed drive, or any pending writes then sidestep the cache */ | |
1582 | if (sh->bh_read[i] && !sh->bh_read[i]->b_reqnext && | |
1583 | ! syncing && !failed && !to_write) { | |
1584 | sh->bh_cache[i]->b_page = sh->bh_read[i]->b_page; | |
1585 | sh->bh_cache[i]->b_data = sh->bh_read[i]->b_data; | |
1586 | } | |
1587 | #endif | |
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) | |
1605 | #if 0 | |
1606 | || sh->bh_page[i]!=bh->b_page | |
1607 | #endif | |
1608 | ) && | |
1609 | !test_bit(R5_UPTODATE, &dev->flags)) { | |
1610 | if (test_bit(R5_Insync, &dev->flags) | |
1611 | /* && !(!mddev->insync && i == sh->pd_idx) */ | |
1612 | ) | |
1613 | rmw++; | |
1614 | else rmw += 2*disks; /* cannot read it */ | |
1615 | } | |
1616 | /* Would I have to read this buffer for reconstruct_write */ | |
1617 | if (!test_bit(R5_OVERWRITE, &dev->flags) && i != sh->pd_idx && | |
1618 | (!test_bit(R5_LOCKED, &dev->flags) | |
1619 | #if 0 | |
1620 | || sh->bh_page[i] != bh->b_page | |
1621 | #endif | |
1622 | ) && | |
1623 | !test_bit(R5_UPTODATE, &dev->flags)) { | |
1624 | if (test_bit(R5_Insync, &dev->flags)) rcw++; | |
1625 | else rcw += 2*disks; | |
1626 | } | |
1627 | } | |
1628 | PRINTK("for sector %llu, rmw=%d rcw=%d\n", | |
1629 | (unsigned long long)sh->sector, rmw, rcw); | |
1630 | set_bit(STRIPE_HANDLE, &sh->state); | |
1631 | if (rmw < rcw && rmw > 0) | |
1632 | /* prefer read-modify-write, but need to get some data */ | |
1633 | for (i=disks; i--;) { | |
1634 | dev = &sh->dev[i]; | |
1635 | if ((dev->towrite || i == sh->pd_idx) && | |
1636 | !test_bit(R5_LOCKED, &dev->flags) && !test_bit(R5_UPTODATE, &dev->flags) && | |
1637 | test_bit(R5_Insync, &dev->flags)) { | |
1638 | if (test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) | |
1639 | { | |
1640 | PRINTK("Read_old block %d for r-m-w\n", i); | |
1641 | set_bit(R5_LOCKED, &dev->flags); | |
1642 | set_bit(R5_Wantread, &dev->flags); | |
1643 | locked++; | |
1644 | } else { | |
1645 | set_bit(STRIPE_DELAYED, &sh->state); | |
1646 | set_bit(STRIPE_HANDLE, &sh->state); | |
1647 | } | |
1648 | } | |
1649 | } | |
1650 | if (rcw <= rmw && rcw > 0) | |
1651 | /* want reconstruct write, but need to get some data */ | |
1652 | for (i=disks; i--;) { | |
1653 | dev = &sh->dev[i]; | |
1654 | if (!test_bit(R5_OVERWRITE, &dev->flags) && i != sh->pd_idx && | |
1655 | !test_bit(R5_LOCKED, &dev->flags) && !test_bit(R5_UPTODATE, &dev->flags) && | |
1656 | test_bit(R5_Insync, &dev->flags)) { | |
1657 | if (test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) | |
1658 | { | |
1659 | PRINTK("Read_old block %d for Reconstruct\n", i); | |
1660 | set_bit(R5_LOCKED, &dev->flags); | |
1661 | set_bit(R5_Wantread, &dev->flags); | |
1662 | locked++; | |
1663 | } else { | |
1664 | set_bit(STRIPE_DELAYED, &sh->state); | |
1665 | set_bit(STRIPE_HANDLE, &sh->state); | |
1666 | } | |
1667 | } | |
1668 | } | |
1669 | /* now if nothing is locked, and if we have enough data, we can start a write request */ | |
72626685 N |
1670 | if (locked == 0 && (rcw == 0 ||rmw == 0) && |
1671 | !test_bit(STRIPE_BIT_DELAY, &sh->state)) { | |
1da177e4 | 1672 | PRINTK("Computing parity...\n"); |
16a53ecc | 1673 | compute_parity5(sh, rcw==0 ? RECONSTRUCT_WRITE : READ_MODIFY_WRITE); |
1da177e4 LT |
1674 | /* now every locked buffer is ready to be written */ |
1675 | for (i=disks; i--;) | |
1676 | if (test_bit(R5_LOCKED, &sh->dev[i].flags)) { | |
1677 | PRINTK("Writing block %d\n", i); | |
1678 | locked++; | |
1679 | set_bit(R5_Wantwrite, &sh->dev[i].flags); | |
1680 | if (!test_bit(R5_Insync, &sh->dev[i].flags) | |
1681 | || (i==sh->pd_idx && failed == 0)) | |
1682 | set_bit(STRIPE_INSYNC, &sh->state); | |
1683 | } | |
1684 | if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
1685 | atomic_dec(&conf->preread_active_stripes); | |
1686 | if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD) | |
1687 | md_wakeup_thread(conf->mddev->thread); | |
1688 | } | |
1689 | } | |
1690 | } | |
1691 | ||
1692 | /* maybe we need to check and possibly fix the parity for this stripe | |
1693 | * Any reads will already have been scheduled, so we just see if enough data | |
1694 | * is available | |
1695 | */ | |
1696 | if (syncing && locked == 0 && | |
14f8d26b | 1697 | !test_bit(STRIPE_INSYNC, &sh->state)) { |
1da177e4 LT |
1698 | set_bit(STRIPE_HANDLE, &sh->state); |
1699 | if (failed == 0) { | |
78bafebd | 1700 | BUG_ON(uptodate != disks); |
16a53ecc | 1701 | compute_parity5(sh, CHECK_PARITY); |
1da177e4 | 1702 | uptodate--; |
16a53ecc | 1703 | if (page_is_zero(sh->dev[sh->pd_idx].page)) { |
1da177e4 LT |
1704 | /* parity is correct (on disc, not in buffer any more) */ |
1705 | set_bit(STRIPE_INSYNC, &sh->state); | |
9d88883e N |
1706 | } else { |
1707 | conf->mddev->resync_mismatches += STRIPE_SECTORS; | |
1708 | if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery)) | |
1709 | /* don't try to repair!! */ | |
1710 | set_bit(STRIPE_INSYNC, &sh->state); | |
14f8d26b N |
1711 | else { |
1712 | compute_block(sh, sh->pd_idx); | |
1713 | uptodate++; | |
1714 | } | |
1da177e4 LT |
1715 | } |
1716 | } | |
1717 | if (!test_bit(STRIPE_INSYNC, &sh->state)) { | |
14f8d26b | 1718 | /* either failed parity check, or recovery is happening */ |
1da177e4 LT |
1719 | if (failed==0) |
1720 | failed_num = sh->pd_idx; | |
1da177e4 | 1721 | dev = &sh->dev[failed_num]; |
14f8d26b N |
1722 | BUG_ON(!test_bit(R5_UPTODATE, &dev->flags)); |
1723 | BUG_ON(uptodate != disks); | |
1724 | ||
1da177e4 LT |
1725 | set_bit(R5_LOCKED, &dev->flags); |
1726 | set_bit(R5_Wantwrite, &dev->flags); | |
72626685 | 1727 | clear_bit(STRIPE_DEGRADED, &sh->state); |
1da177e4 LT |
1728 | locked++; |
1729 | set_bit(STRIPE_INSYNC, &sh->state); | |
1da177e4 LT |
1730 | } |
1731 | } | |
1732 | if (syncing && locked == 0 && test_bit(STRIPE_INSYNC, &sh->state)) { | |
1733 | md_done_sync(conf->mddev, STRIPE_SECTORS,1); | |
1734 | clear_bit(STRIPE_SYNCING, &sh->state); | |
1735 | } | |
4e5314b5 N |
1736 | |
1737 | /* If the failed drive is just a ReadError, then we might need to progress | |
1738 | * the repair/check process | |
1739 | */ | |
ba22dcbf N |
1740 | if (failed == 1 && ! conf->mddev->ro && |
1741 | test_bit(R5_ReadError, &sh->dev[failed_num].flags) | |
4e5314b5 N |
1742 | && !test_bit(R5_LOCKED, &sh->dev[failed_num].flags) |
1743 | && test_bit(R5_UPTODATE, &sh->dev[failed_num].flags) | |
1744 | ) { | |
1745 | dev = &sh->dev[failed_num]; | |
1746 | if (!test_bit(R5_ReWrite, &dev->flags)) { | |
1747 | set_bit(R5_Wantwrite, &dev->flags); | |
1748 | set_bit(R5_ReWrite, &dev->flags); | |
1749 | set_bit(R5_LOCKED, &dev->flags); | |
ccfcc3c1 | 1750 | locked++; |
4e5314b5 N |
1751 | } else { |
1752 | /* let's read it back */ | |
1753 | set_bit(R5_Wantread, &dev->flags); | |
1754 | set_bit(R5_LOCKED, &dev->flags); | |
ccfcc3c1 | 1755 | locked++; |
4e5314b5 N |
1756 | } |
1757 | } | |
1758 | ||
ccfcc3c1 N |
1759 | if (expanded && test_bit(STRIPE_EXPANDING, &sh->state)) { |
1760 | /* Need to write out all blocks after computing parity */ | |
1761 | sh->disks = conf->raid_disks; | |
1762 | sh->pd_idx = stripe_to_pdidx(sh->sector, conf, conf->raid_disks); | |
16a53ecc | 1763 | compute_parity5(sh, RECONSTRUCT_WRITE); |
ccfcc3c1 N |
1764 | for (i= conf->raid_disks; i--;) { |
1765 | set_bit(R5_LOCKED, &sh->dev[i].flags); | |
1766 | locked++; | |
1767 | set_bit(R5_Wantwrite, &sh->dev[i].flags); | |
1768 | } | |
1769 | clear_bit(STRIPE_EXPANDING, &sh->state); | |
1770 | } else if (expanded) { | |
1771 | clear_bit(STRIPE_EXPAND_READY, &sh->state); | |
f6705578 | 1772 | atomic_dec(&conf->reshape_stripes); |
ccfcc3c1 N |
1773 | wake_up(&conf->wait_for_overlap); |
1774 | md_done_sync(conf->mddev, STRIPE_SECTORS, 1); | |
1775 | } | |
1776 | ||
1777 | if (expanding && locked == 0) { | |
1778 | /* We have read all the blocks in this stripe and now we need to | |
1779 | * copy some of them into a target stripe for expand. | |
1780 | */ | |
1781 | clear_bit(STRIPE_EXPAND_SOURCE, &sh->state); | |
1782 | for (i=0; i< sh->disks; i++) | |
1783 | if (i != sh->pd_idx) { | |
1784 | int dd_idx, pd_idx, j; | |
1785 | struct stripe_head *sh2; | |
1786 | ||
1787 | sector_t bn = compute_blocknr(sh, i); | |
1788 | sector_t s = raid5_compute_sector(bn, conf->raid_disks, | |
1789 | conf->raid_disks-1, | |
1790 | &dd_idx, &pd_idx, conf); | |
1791 | sh2 = get_active_stripe(conf, s, conf->raid_disks, pd_idx, 1); | |
1792 | if (sh2 == NULL) | |
1793 | /* so far only the early blocks of this stripe | |
1794 | * have been requested. When later blocks | |
1795 | * get requested, we will try again | |
1796 | */ | |
1797 | continue; | |
1798 | if(!test_bit(STRIPE_EXPANDING, &sh2->state) || | |
1799 | test_bit(R5_Expanded, &sh2->dev[dd_idx].flags)) { | |
1800 | /* must have already done this block */ | |
1801 | release_stripe(sh2); | |
1802 | continue; | |
1803 | } | |
1804 | memcpy(page_address(sh2->dev[dd_idx].page), | |
1805 | page_address(sh->dev[i].page), | |
1806 | STRIPE_SIZE); | |
1807 | set_bit(R5_Expanded, &sh2->dev[dd_idx].flags); | |
1808 | set_bit(R5_UPTODATE, &sh2->dev[dd_idx].flags); | |
1809 | for (j=0; j<conf->raid_disks; j++) | |
1810 | if (j != sh2->pd_idx && | |
1811 | !test_bit(R5_Expanded, &sh2->dev[j].flags)) | |
1812 | break; | |
1813 | if (j == conf->raid_disks) { | |
1814 | set_bit(STRIPE_EXPAND_READY, &sh2->state); | |
1815 | set_bit(STRIPE_HANDLE, &sh2->state); | |
1816 | } | |
1817 | release_stripe(sh2); | |
1818 | } | |
1819 | } | |
1820 | ||
1da177e4 LT |
1821 | spin_unlock(&sh->lock); |
1822 | ||
1823 | while ((bi=return_bi)) { | |
1824 | int bytes = bi->bi_size; | |
1825 | ||
1826 | return_bi = bi->bi_next; | |
1827 | bi->bi_next = NULL; | |
1828 | bi->bi_size = 0; | |
1829 | bi->bi_end_io(bi, bytes, 0); | |
1830 | } | |
1831 | for (i=disks; i-- ;) { | |
1832 | int rw; | |
1833 | struct bio *bi; | |
1834 | mdk_rdev_t *rdev; | |
1835 | if (test_and_clear_bit(R5_Wantwrite, &sh->dev[i].flags)) | |
1836 | rw = 1; | |
1837 | else if (test_and_clear_bit(R5_Wantread, &sh->dev[i].flags)) | |
1838 | rw = 0; | |
1839 | else | |
1840 | continue; | |
1841 | ||
1842 | bi = &sh->dev[i].req; | |
1843 | ||
1844 | bi->bi_rw = rw; | |
1845 | if (rw) | |
1846 | bi->bi_end_io = raid5_end_write_request; | |
1847 | else | |
1848 | bi->bi_end_io = raid5_end_read_request; | |
1849 | ||
1850 | rcu_read_lock(); | |
d6065f7b | 1851 | rdev = rcu_dereference(conf->disks[i].rdev); |
b2d444d7 | 1852 | if (rdev && test_bit(Faulty, &rdev->flags)) |
1da177e4 LT |
1853 | rdev = NULL; |
1854 | if (rdev) | |
1855 | atomic_inc(&rdev->nr_pending); | |
1856 | rcu_read_unlock(); | |
1857 | ||
1858 | if (rdev) { | |
ccfcc3c1 | 1859 | if (syncing || expanding || expanded) |
1da177e4 LT |
1860 | md_sync_acct(rdev->bdev, STRIPE_SECTORS); |
1861 | ||
1862 | bi->bi_bdev = rdev->bdev; | |
1863 | PRINTK("for %llu schedule op %ld on disc %d\n", | |
1864 | (unsigned long long)sh->sector, bi->bi_rw, i); | |
1865 | atomic_inc(&sh->count); | |
1866 | bi->bi_sector = sh->sector + rdev->data_offset; | |
1867 | bi->bi_flags = 1 << BIO_UPTODATE; | |
1868 | bi->bi_vcnt = 1; | |
1869 | bi->bi_max_vecs = 1; | |
1870 | bi->bi_idx = 0; | |
1871 | bi->bi_io_vec = &sh->dev[i].vec; | |
1872 | bi->bi_io_vec[0].bv_len = STRIPE_SIZE; | |
1873 | bi->bi_io_vec[0].bv_offset = 0; | |
1874 | bi->bi_size = STRIPE_SIZE; | |
1875 | bi->bi_next = NULL; | |
4dbcdc75 N |
1876 | if (rw == WRITE && |
1877 | test_bit(R5_ReWrite, &sh->dev[i].flags)) | |
1878 | atomic_add(STRIPE_SECTORS, &rdev->corrected_errors); | |
1da177e4 LT |
1879 | generic_make_request(bi); |
1880 | } else { | |
72626685 N |
1881 | if (rw == 1) |
1882 | set_bit(STRIPE_DEGRADED, &sh->state); | |
1da177e4 LT |
1883 | PRINTK("skip op %ld on disc %d for sector %llu\n", |
1884 | bi->bi_rw, i, (unsigned long long)sh->sector); | |
1885 | clear_bit(R5_LOCKED, &sh->dev[i].flags); | |
1886 | set_bit(STRIPE_HANDLE, &sh->state); | |
1887 | } | |
1888 | } | |
1889 | } | |
1890 | ||
16a53ecc | 1891 | static void handle_stripe6(struct stripe_head *sh, struct page *tmp_page) |
1da177e4 | 1892 | { |
16a53ecc N |
1893 | raid6_conf_t *conf = sh->raid_conf; |
1894 | int disks = conf->raid_disks; | |
1895 | struct bio *return_bi= NULL; | |
1896 | struct bio *bi; | |
1897 | int i; | |
1898 | int syncing; | |
1899 | int locked=0, uptodate=0, to_read=0, to_write=0, failed=0, written=0; | |
1900 | int non_overwrite = 0; | |
1901 | int failed_num[2] = {0, 0}; | |
1902 | struct r5dev *dev, *pdev, *qdev; | |
1903 | int pd_idx = sh->pd_idx; | |
1904 | int qd_idx = raid6_next_disk(pd_idx, disks); | |
1905 | int p_failed, q_failed; | |
1da177e4 | 1906 | |
16a53ecc N |
1907 | PRINTK("handling stripe %llu, state=%#lx cnt=%d, pd_idx=%d, qd_idx=%d\n", |
1908 | (unsigned long long)sh->sector, sh->state, atomic_read(&sh->count), | |
1909 | pd_idx, qd_idx); | |
72626685 | 1910 | |
16a53ecc N |
1911 | spin_lock(&sh->lock); |
1912 | clear_bit(STRIPE_HANDLE, &sh->state); | |
1913 | clear_bit(STRIPE_DELAYED, &sh->state); | |
1914 | ||
1915 | syncing = test_bit(STRIPE_SYNCING, &sh->state); | |
1916 | /* Now to look around and see what can be done */ | |
1da177e4 LT |
1917 | |
1918 | rcu_read_lock(); | |
16a53ecc N |
1919 | for (i=disks; i--; ) { |
1920 | mdk_rdev_t *rdev; | |
1921 | dev = &sh->dev[i]; | |
1922 | clear_bit(R5_Insync, &dev->flags); | |
1da177e4 | 1923 | |
16a53ecc N |
1924 | PRINTK("check %d: state 0x%lx read %p write %p written %p\n", |
1925 | i, dev->flags, dev->toread, dev->towrite, dev->written); | |
1926 | /* maybe we can reply to a read */ | |
1927 | if (test_bit(R5_UPTODATE, &dev->flags) && dev->toread) { | |
1928 | struct bio *rbi, *rbi2; | |
1929 | PRINTK("Return read for disc %d\n", i); | |
1930 | spin_lock_irq(&conf->device_lock); | |
1931 | rbi = dev->toread; | |
1932 | dev->toread = NULL; | |
1933 | if (test_and_clear_bit(R5_Overlap, &dev->flags)) | |
1934 | wake_up(&conf->wait_for_overlap); | |
1935 | spin_unlock_irq(&conf->device_lock); | |
1936 | while (rbi && rbi->bi_sector < dev->sector + STRIPE_SECTORS) { | |
1937 | copy_data(0, rbi, dev->page, dev->sector); | |
1938 | rbi2 = r5_next_bio(rbi, dev->sector); | |
1939 | spin_lock_irq(&conf->device_lock); | |
1940 | if (--rbi->bi_phys_segments == 0) { | |
1941 | rbi->bi_next = return_bi; | |
1942 | return_bi = rbi; | |
1943 | } | |
1944 | spin_unlock_irq(&conf->device_lock); | |
1945 | rbi = rbi2; | |
1946 | } | |
1947 | } | |
1da177e4 | 1948 | |
16a53ecc N |
1949 | /* now count some things */ |
1950 | if (test_bit(R5_LOCKED, &dev->flags)) locked++; | |
1951 | if (test_bit(R5_UPTODATE, &dev->flags)) uptodate++; | |
1da177e4 | 1952 | |
16a53ecc N |
1953 | |
1954 | if (dev->toread) to_read++; | |
1955 | if (dev->towrite) { | |
1956 | to_write++; | |
1957 | if (!test_bit(R5_OVERWRITE, &dev->flags)) | |
1958 | non_overwrite++; | |
1959 | } | |
1960 | if (dev->written) written++; | |
1961 | rdev = rcu_dereference(conf->disks[i].rdev); | |
1962 | if (!rdev || !test_bit(In_sync, &rdev->flags)) { | |
1963 | /* The ReadError flag will just be confusing now */ | |
1964 | clear_bit(R5_ReadError, &dev->flags); | |
1965 | clear_bit(R5_ReWrite, &dev->flags); | |
1da177e4 | 1966 | } |
16a53ecc N |
1967 | if (!rdev || !test_bit(In_sync, &rdev->flags) |
1968 | || test_bit(R5_ReadError, &dev->flags)) { | |
1969 | if ( failed < 2 ) | |
1970 | failed_num[failed] = i; | |
1971 | failed++; | |
1972 | } else | |
1973 | set_bit(R5_Insync, &dev->flags); | |
1da177e4 LT |
1974 | } |
1975 | rcu_read_unlock(); | |
16a53ecc N |
1976 | PRINTK("locked=%d uptodate=%d to_read=%d" |
1977 | " to_write=%d failed=%d failed_num=%d,%d\n", | |
1978 | locked, uptodate, to_read, to_write, failed, | |
1979 | failed_num[0], failed_num[1]); | |
1980 | /* check if the array has lost >2 devices and, if so, some requests might | |
1981 | * need to be failed | |
1982 | */ | |
1983 | if (failed > 2 && to_read+to_write+written) { | |
1984 | for (i=disks; i--; ) { | |
1985 | int bitmap_end = 0; | |
1da177e4 | 1986 | |
16a53ecc N |
1987 | if (test_bit(R5_ReadError, &sh->dev[i].flags)) { |
1988 | mdk_rdev_t *rdev; | |
1989 | rcu_read_lock(); | |
1990 | rdev = rcu_dereference(conf->disks[i].rdev); | |
1991 | if (rdev && test_bit(In_sync, &rdev->flags)) | |
1992 | /* multiple read failures in one stripe */ | |
1993 | md_error(conf->mddev, rdev); | |
1994 | rcu_read_unlock(); | |
1995 | } | |
1da177e4 | 1996 | |
16a53ecc N |
1997 | spin_lock_irq(&conf->device_lock); |
1998 | /* fail all writes first */ | |
1999 | bi = sh->dev[i].towrite; | |
2000 | sh->dev[i].towrite = NULL; | |
2001 | if (bi) { to_write--; bitmap_end = 1; } | |
1da177e4 | 2002 | |
16a53ecc N |
2003 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) |
2004 | wake_up(&conf->wait_for_overlap); | |
2005 | ||
2006 | while (bi && bi->bi_sector < sh->dev[i].sector + STRIPE_SECTORS){ | |
2007 | struct bio *nextbi = r5_next_bio(bi, sh->dev[i].sector); | |
2008 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
2009 | if (--bi->bi_phys_segments == 0) { | |
2010 | md_write_end(conf->mddev); | |
2011 | bi->bi_next = return_bi; | |
2012 | return_bi = bi; | |
2013 | } | |
2014 | bi = nextbi; | |
2015 | } | |
2016 | /* and fail all 'written' */ | |
2017 | bi = sh->dev[i].written; | |
2018 | sh->dev[i].written = NULL; | |
2019 | if (bi) bitmap_end = 1; | |
2020 | while (bi && bi->bi_sector < sh->dev[i].sector + STRIPE_SECTORS) { | |
2021 | struct bio *bi2 = r5_next_bio(bi, sh->dev[i].sector); | |
2022 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
2023 | if (--bi->bi_phys_segments == 0) { | |
2024 | md_write_end(conf->mddev); | |
2025 | bi->bi_next = return_bi; | |
2026 | return_bi = bi; | |
2027 | } | |
2028 | bi = bi2; | |
2029 | } | |
2030 | ||
2031 | /* fail any reads if this device is non-operational */ | |
2032 | if (!test_bit(R5_Insync, &sh->dev[i].flags) || | |
2033 | test_bit(R5_ReadError, &sh->dev[i].flags)) { | |
2034 | bi = sh->dev[i].toread; | |
2035 | sh->dev[i].toread = NULL; | |
2036 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) | |
2037 | wake_up(&conf->wait_for_overlap); | |
2038 | if (bi) to_read--; | |
2039 | while (bi && bi->bi_sector < sh->dev[i].sector + STRIPE_SECTORS){ | |
2040 | struct bio *nextbi = r5_next_bio(bi, sh->dev[i].sector); | |
2041 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
2042 | if (--bi->bi_phys_segments == 0) { | |
2043 | bi->bi_next = return_bi; | |
2044 | return_bi = bi; | |
2045 | } | |
2046 | bi = nextbi; | |
2047 | } | |
2048 | } | |
2049 | spin_unlock_irq(&conf->device_lock); | |
2050 | if (bitmap_end) | |
2051 | bitmap_endwrite(conf->mddev->bitmap, sh->sector, | |
2052 | STRIPE_SECTORS, 0, 0); | |
2053 | } | |
2054 | } | |
2055 | if (failed > 2 && syncing) { | |
2056 | md_done_sync(conf->mddev, STRIPE_SECTORS,0); | |
2057 | clear_bit(STRIPE_SYNCING, &sh->state); | |
2058 | syncing = 0; | |
2059 | } | |
2060 | ||
2061 | /* | |
2062 | * might be able to return some write requests if the parity blocks | |
2063 | * are safe, or on a failed drive | |
2064 | */ | |
2065 | pdev = &sh->dev[pd_idx]; | |
2066 | p_failed = (failed >= 1 && failed_num[0] == pd_idx) | |
2067 | || (failed >= 2 && failed_num[1] == pd_idx); | |
2068 | qdev = &sh->dev[qd_idx]; | |
2069 | q_failed = (failed >= 1 && failed_num[0] == qd_idx) | |
2070 | || (failed >= 2 && failed_num[1] == qd_idx); | |
2071 | ||
2072 | if ( written && | |
2073 | ( p_failed || ((test_bit(R5_Insync, &pdev->flags) | |
2074 | && !test_bit(R5_LOCKED, &pdev->flags) | |
2075 | && test_bit(R5_UPTODATE, &pdev->flags))) ) && | |
2076 | ( q_failed || ((test_bit(R5_Insync, &qdev->flags) | |
2077 | && !test_bit(R5_LOCKED, &qdev->flags) | |
2078 | && test_bit(R5_UPTODATE, &qdev->flags))) ) ) { | |
2079 | /* any written block on an uptodate or failed drive can be | |
2080 | * returned. Note that if we 'wrote' to a failed drive, | |
2081 | * it will be UPTODATE, but never LOCKED, so we don't need | |
2082 | * to test 'failed' directly. | |
2083 | */ | |
2084 | for (i=disks; i--; ) | |
2085 | if (sh->dev[i].written) { | |
2086 | dev = &sh->dev[i]; | |
2087 | if (!test_bit(R5_LOCKED, &dev->flags) && | |
2088 | test_bit(R5_UPTODATE, &dev->flags) ) { | |
2089 | /* We can return any write requests */ | |
2090 | int bitmap_end = 0; | |
2091 | struct bio *wbi, *wbi2; | |
2092 | PRINTK("Return write for stripe %llu disc %d\n", | |
2093 | (unsigned long long)sh->sector, i); | |
2094 | spin_lock_irq(&conf->device_lock); | |
2095 | wbi = dev->written; | |
2096 | dev->written = NULL; | |
2097 | while (wbi && wbi->bi_sector < dev->sector + STRIPE_SECTORS) { | |
2098 | wbi2 = r5_next_bio(wbi, dev->sector); | |
2099 | if (--wbi->bi_phys_segments == 0) { | |
2100 | md_write_end(conf->mddev); | |
2101 | wbi->bi_next = return_bi; | |
2102 | return_bi = wbi; | |
2103 | } | |
2104 | wbi = wbi2; | |
2105 | } | |
2106 | if (dev->towrite == NULL) | |
2107 | bitmap_end = 1; | |
2108 | spin_unlock_irq(&conf->device_lock); | |
2109 | if (bitmap_end) | |
2110 | bitmap_endwrite(conf->mddev->bitmap, sh->sector, | |
2111 | STRIPE_SECTORS, | |
2112 | !test_bit(STRIPE_DEGRADED, &sh->state), 0); | |
2113 | } | |
2114 | } | |
2115 | } | |
2116 | ||
2117 | /* Now we might consider reading some blocks, either to check/generate | |
2118 | * parity, or to satisfy requests | |
2119 | * or to load a block that is being partially written. | |
2120 | */ | |
2121 | if (to_read || non_overwrite || (to_write && failed) || (syncing && (uptodate < disks))) { | |
2122 | for (i=disks; i--;) { | |
2123 | dev = &sh->dev[i]; | |
2124 | if (!test_bit(R5_LOCKED, &dev->flags) && !test_bit(R5_UPTODATE, &dev->flags) && | |
2125 | (dev->toread || | |
2126 | (dev->towrite && !test_bit(R5_OVERWRITE, &dev->flags)) || | |
2127 | syncing || | |
2128 | (failed >= 1 && (sh->dev[failed_num[0]].toread || to_write)) || | |
2129 | (failed >= 2 && (sh->dev[failed_num[1]].toread || to_write)) | |
2130 | ) | |
2131 | ) { | |
2132 | /* we would like to get this block, possibly | |
2133 | * by computing it, but we might not be able to | |
2134 | */ | |
2135 | if (uptodate == disks-1) { | |
2136 | PRINTK("Computing stripe %llu block %d\n", | |
2137 | (unsigned long long)sh->sector, i); | |
2138 | compute_block_1(sh, i, 0); | |
2139 | uptodate++; | |
2140 | } else if ( uptodate == disks-2 && failed >= 2 ) { | |
2141 | /* Computing 2-failure is *very* expensive; only do it if failed >= 2 */ | |
2142 | int other; | |
2143 | for (other=disks; other--;) { | |
2144 | if ( other == i ) | |
2145 | continue; | |
2146 | if ( !test_bit(R5_UPTODATE, &sh->dev[other].flags) ) | |
2147 | break; | |
2148 | } | |
2149 | BUG_ON(other < 0); | |
2150 | PRINTK("Computing stripe %llu blocks %d,%d\n", | |
2151 | (unsigned long long)sh->sector, i, other); | |
2152 | compute_block_2(sh, i, other); | |
2153 | uptodate += 2; | |
2154 | } else if (test_bit(R5_Insync, &dev->flags)) { | |
2155 | set_bit(R5_LOCKED, &dev->flags); | |
2156 | set_bit(R5_Wantread, &dev->flags); | |
2157 | #if 0 | |
2158 | /* if I am just reading this block and we don't have | |
2159 | a failed drive, or any pending writes then sidestep the cache */ | |
2160 | if (sh->bh_read[i] && !sh->bh_read[i]->b_reqnext && | |
2161 | ! syncing && !failed && !to_write) { | |
2162 | sh->bh_cache[i]->b_page = sh->bh_read[i]->b_page; | |
2163 | sh->bh_cache[i]->b_data = sh->bh_read[i]->b_data; | |
2164 | } | |
2165 | #endif | |
2166 | locked++; | |
2167 | PRINTK("Reading block %d (sync=%d)\n", | |
2168 | i, syncing); | |
2169 | } | |
2170 | } | |
2171 | } | |
2172 | set_bit(STRIPE_HANDLE, &sh->state); | |
2173 | } | |
2174 | ||
2175 | /* now to consider writing and what else, if anything should be read */ | |
2176 | if (to_write) { | |
2177 | int rcw=0, must_compute=0; | |
2178 | for (i=disks ; i--;) { | |
2179 | dev = &sh->dev[i]; | |
2180 | /* Would I have to read this buffer for reconstruct_write */ | |
2181 | if (!test_bit(R5_OVERWRITE, &dev->flags) | |
2182 | && i != pd_idx && i != qd_idx | |
2183 | && (!test_bit(R5_LOCKED, &dev->flags) | |
2184 | #if 0 | |
2185 | || sh->bh_page[i] != bh->b_page | |
2186 | #endif | |
2187 | ) && | |
2188 | !test_bit(R5_UPTODATE, &dev->flags)) { | |
2189 | if (test_bit(R5_Insync, &dev->flags)) rcw++; | |
2190 | else { | |
2191 | PRINTK("raid6: must_compute: disk %d flags=%#lx\n", i, dev->flags); | |
2192 | must_compute++; | |
2193 | } | |
2194 | } | |
2195 | } | |
2196 | PRINTK("for sector %llu, rcw=%d, must_compute=%d\n", | |
2197 | (unsigned long long)sh->sector, rcw, must_compute); | |
2198 | set_bit(STRIPE_HANDLE, &sh->state); | |
2199 | ||
2200 | if (rcw > 0) | |
2201 | /* want reconstruct write, but need to get some data */ | |
2202 | for (i=disks; i--;) { | |
2203 | dev = &sh->dev[i]; | |
2204 | if (!test_bit(R5_OVERWRITE, &dev->flags) | |
2205 | && !(failed == 0 && (i == pd_idx || i == qd_idx)) | |
2206 | && !test_bit(R5_LOCKED, &dev->flags) && !test_bit(R5_UPTODATE, &dev->flags) && | |
2207 | test_bit(R5_Insync, &dev->flags)) { | |
2208 | if (test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) | |
2209 | { | |
2210 | PRINTK("Read_old stripe %llu block %d for Reconstruct\n", | |
2211 | (unsigned long long)sh->sector, i); | |
2212 | set_bit(R5_LOCKED, &dev->flags); | |
2213 | set_bit(R5_Wantread, &dev->flags); | |
2214 | locked++; | |
2215 | } else { | |
2216 | PRINTK("Request delayed stripe %llu block %d for Reconstruct\n", | |
2217 | (unsigned long long)sh->sector, i); | |
2218 | set_bit(STRIPE_DELAYED, &sh->state); | |
2219 | set_bit(STRIPE_HANDLE, &sh->state); | |
2220 | } | |
2221 | } | |
2222 | } | |
2223 | /* now if nothing is locked, and if we have enough data, we can start a write request */ | |
2224 | if (locked == 0 && rcw == 0 && | |
2225 | !test_bit(STRIPE_BIT_DELAY, &sh->state)) { | |
2226 | if ( must_compute > 0 ) { | |
2227 | /* We have failed blocks and need to compute them */ | |
2228 | switch ( failed ) { | |
2229 | case 0: BUG(); | |
2230 | case 1: compute_block_1(sh, failed_num[0], 0); break; | |
2231 | case 2: compute_block_2(sh, failed_num[0], failed_num[1]); break; | |
2232 | default: BUG(); /* This request should have been failed? */ | |
2233 | } | |
2234 | } | |
2235 | ||
2236 | PRINTK("Computing parity for stripe %llu\n", (unsigned long long)sh->sector); | |
2237 | compute_parity6(sh, RECONSTRUCT_WRITE); | |
2238 | /* now every locked buffer is ready to be written */ | |
2239 | for (i=disks; i--;) | |
2240 | if (test_bit(R5_LOCKED, &sh->dev[i].flags)) { | |
2241 | PRINTK("Writing stripe %llu block %d\n", | |
2242 | (unsigned long long)sh->sector, i); | |
2243 | locked++; | |
2244 | set_bit(R5_Wantwrite, &sh->dev[i].flags); | |
2245 | } | |
2246 | /* after a RECONSTRUCT_WRITE, the stripe MUST be in-sync */ | |
2247 | set_bit(STRIPE_INSYNC, &sh->state); | |
2248 | ||
2249 | if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
2250 | atomic_dec(&conf->preread_active_stripes); | |
2251 | if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD) | |
2252 | md_wakeup_thread(conf->mddev->thread); | |
2253 | } | |
2254 | } | |
2255 | } | |
2256 | ||
2257 | /* maybe we need to check and possibly fix the parity for this stripe | |
2258 | * Any reads will already have been scheduled, so we just see if enough data | |
2259 | * is available | |
2260 | */ | |
2261 | if (syncing && locked == 0 && !test_bit(STRIPE_INSYNC, &sh->state)) { | |
2262 | int update_p = 0, update_q = 0; | |
2263 | struct r5dev *dev; | |
2264 | ||
2265 | set_bit(STRIPE_HANDLE, &sh->state); | |
2266 | ||
2267 | BUG_ON(failed>2); | |
2268 | BUG_ON(uptodate < disks); | |
2269 | /* Want to check and possibly repair P and Q. | |
2270 | * However there could be one 'failed' device, in which | |
2271 | * case we can only check one of them, possibly using the | |
2272 | * other to generate missing data | |
2273 | */ | |
2274 | ||
2275 | /* If !tmp_page, we cannot do the calculations, | |
2276 | * but as we have set STRIPE_HANDLE, we will soon be called | |
2277 | * by stripe_handle with a tmp_page - just wait until then. | |
2278 | */ | |
2279 | if (tmp_page) { | |
2280 | if (failed == q_failed) { | |
2281 | /* The only possible failed device holds 'Q', so it makes | |
2282 | * sense to check P (If anything else were failed, we would | |
2283 | * have used P to recreate it). | |
2284 | */ | |
2285 | compute_block_1(sh, pd_idx, 1); | |
2286 | if (!page_is_zero(sh->dev[pd_idx].page)) { | |
2287 | compute_block_1(sh,pd_idx,0); | |
2288 | update_p = 1; | |
2289 | } | |
2290 | } | |
2291 | if (!q_failed && failed < 2) { | |
2292 | /* q is not failed, and we didn't use it to generate | |
2293 | * anything, so it makes sense to check it | |
2294 | */ | |
2295 | memcpy(page_address(tmp_page), | |
2296 | page_address(sh->dev[qd_idx].page), | |
2297 | STRIPE_SIZE); | |
2298 | compute_parity6(sh, UPDATE_PARITY); | |
2299 | if (memcmp(page_address(tmp_page), | |
2300 | page_address(sh->dev[qd_idx].page), | |
2301 | STRIPE_SIZE)!= 0) { | |
2302 | clear_bit(STRIPE_INSYNC, &sh->state); | |
2303 | update_q = 1; | |
2304 | } | |
2305 | } | |
2306 | if (update_p || update_q) { | |
2307 | conf->mddev->resync_mismatches += STRIPE_SECTORS; | |
2308 | if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery)) | |
2309 | /* don't try to repair!! */ | |
2310 | update_p = update_q = 0; | |
2311 | } | |
2312 | ||
2313 | /* now write out any block on a failed drive, | |
2314 | * or P or Q if they need it | |
2315 | */ | |
2316 | ||
2317 | if (failed == 2) { | |
2318 | dev = &sh->dev[failed_num[1]]; | |
2319 | locked++; | |
2320 | set_bit(R5_LOCKED, &dev->flags); | |
2321 | set_bit(R5_Wantwrite, &dev->flags); | |
2322 | } | |
2323 | if (failed >= 1) { | |
2324 | dev = &sh->dev[failed_num[0]]; | |
2325 | locked++; | |
2326 | set_bit(R5_LOCKED, &dev->flags); | |
2327 | set_bit(R5_Wantwrite, &dev->flags); | |
2328 | } | |
2329 | ||
2330 | if (update_p) { | |
2331 | dev = &sh->dev[pd_idx]; | |
2332 | locked ++; | |
2333 | set_bit(R5_LOCKED, &dev->flags); | |
2334 | set_bit(R5_Wantwrite, &dev->flags); | |
2335 | } | |
2336 | if (update_q) { | |
2337 | dev = &sh->dev[qd_idx]; | |
2338 | locked++; | |
2339 | set_bit(R5_LOCKED, &dev->flags); | |
2340 | set_bit(R5_Wantwrite, &dev->flags); | |
2341 | } | |
2342 | clear_bit(STRIPE_DEGRADED, &sh->state); | |
2343 | ||
2344 | set_bit(STRIPE_INSYNC, &sh->state); | |
2345 | } | |
2346 | } | |
2347 | ||
2348 | if (syncing && locked == 0 && test_bit(STRIPE_INSYNC, &sh->state)) { | |
2349 | md_done_sync(conf->mddev, STRIPE_SECTORS,1); | |
2350 | clear_bit(STRIPE_SYNCING, &sh->state); | |
2351 | } | |
2352 | ||
2353 | /* If the failed drives are just a ReadError, then we might need | |
2354 | * to progress the repair/check process | |
2355 | */ | |
2356 | if (failed <= 2 && ! conf->mddev->ro) | |
2357 | for (i=0; i<failed;i++) { | |
2358 | dev = &sh->dev[failed_num[i]]; | |
2359 | if (test_bit(R5_ReadError, &dev->flags) | |
2360 | && !test_bit(R5_LOCKED, &dev->flags) | |
2361 | && test_bit(R5_UPTODATE, &dev->flags) | |
2362 | ) { | |
2363 | if (!test_bit(R5_ReWrite, &dev->flags)) { | |
2364 | set_bit(R5_Wantwrite, &dev->flags); | |
2365 | set_bit(R5_ReWrite, &dev->flags); | |
2366 | set_bit(R5_LOCKED, &dev->flags); | |
2367 | } else { | |
2368 | /* let's read it back */ | |
2369 | set_bit(R5_Wantread, &dev->flags); | |
2370 | set_bit(R5_LOCKED, &dev->flags); | |
2371 | } | |
2372 | } | |
2373 | } | |
2374 | spin_unlock(&sh->lock); | |
2375 | ||
2376 | while ((bi=return_bi)) { | |
2377 | int bytes = bi->bi_size; | |
2378 | ||
2379 | return_bi = bi->bi_next; | |
2380 | bi->bi_next = NULL; | |
2381 | bi->bi_size = 0; | |
2382 | bi->bi_end_io(bi, bytes, 0); | |
2383 | } | |
2384 | for (i=disks; i-- ;) { | |
2385 | int rw; | |
2386 | struct bio *bi; | |
2387 | mdk_rdev_t *rdev; | |
2388 | if (test_and_clear_bit(R5_Wantwrite, &sh->dev[i].flags)) | |
2389 | rw = 1; | |
2390 | else if (test_and_clear_bit(R5_Wantread, &sh->dev[i].flags)) | |
2391 | rw = 0; | |
2392 | else | |
2393 | continue; | |
2394 | ||
2395 | bi = &sh->dev[i].req; | |
2396 | ||
2397 | bi->bi_rw = rw; | |
2398 | if (rw) | |
2399 | bi->bi_end_io = raid5_end_write_request; | |
2400 | else | |
2401 | bi->bi_end_io = raid5_end_read_request; | |
2402 | ||
2403 | rcu_read_lock(); | |
2404 | rdev = rcu_dereference(conf->disks[i].rdev); | |
2405 | if (rdev && test_bit(Faulty, &rdev->flags)) | |
2406 | rdev = NULL; | |
2407 | if (rdev) | |
2408 | atomic_inc(&rdev->nr_pending); | |
2409 | rcu_read_unlock(); | |
2410 | ||
2411 | if (rdev) { | |
2412 | if (syncing) | |
2413 | md_sync_acct(rdev->bdev, STRIPE_SECTORS); | |
2414 | ||
2415 | bi->bi_bdev = rdev->bdev; | |
2416 | PRINTK("for %llu schedule op %ld on disc %d\n", | |
2417 | (unsigned long long)sh->sector, bi->bi_rw, i); | |
2418 | atomic_inc(&sh->count); | |
2419 | bi->bi_sector = sh->sector + rdev->data_offset; | |
2420 | bi->bi_flags = 1 << BIO_UPTODATE; | |
2421 | bi->bi_vcnt = 1; | |
2422 | bi->bi_max_vecs = 1; | |
2423 | bi->bi_idx = 0; | |
2424 | bi->bi_io_vec = &sh->dev[i].vec; | |
2425 | bi->bi_io_vec[0].bv_len = STRIPE_SIZE; | |
2426 | bi->bi_io_vec[0].bv_offset = 0; | |
2427 | bi->bi_size = STRIPE_SIZE; | |
2428 | bi->bi_next = NULL; | |
2429 | if (rw == WRITE && | |
2430 | test_bit(R5_ReWrite, &sh->dev[i].flags)) | |
2431 | atomic_add(STRIPE_SECTORS, &rdev->corrected_errors); | |
2432 | generic_make_request(bi); | |
2433 | } else { | |
2434 | if (rw == 1) | |
2435 | set_bit(STRIPE_DEGRADED, &sh->state); | |
2436 | PRINTK("skip op %ld on disc %d for sector %llu\n", | |
2437 | bi->bi_rw, i, (unsigned long long)sh->sector); | |
2438 | clear_bit(R5_LOCKED, &sh->dev[i].flags); | |
2439 | set_bit(STRIPE_HANDLE, &sh->state); | |
2440 | } | |
2441 | } | |
2442 | } | |
2443 | ||
2444 | static void handle_stripe(struct stripe_head *sh, struct page *tmp_page) | |
2445 | { | |
2446 | if (sh->raid_conf->level == 6) | |
2447 | handle_stripe6(sh, tmp_page); | |
2448 | else | |
2449 | handle_stripe5(sh); | |
2450 | } | |
2451 | ||
2452 | ||
2453 | ||
2454 | static void raid5_activate_delayed(raid5_conf_t *conf) | |
2455 | { | |
2456 | if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD) { | |
2457 | while (!list_empty(&conf->delayed_list)) { | |
2458 | struct list_head *l = conf->delayed_list.next; | |
2459 | struct stripe_head *sh; | |
2460 | sh = list_entry(l, struct stripe_head, lru); | |
2461 | list_del_init(l); | |
2462 | clear_bit(STRIPE_DELAYED, &sh->state); | |
2463 | if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) | |
2464 | atomic_inc(&conf->preread_active_stripes); | |
2465 | list_add_tail(&sh->lru, &conf->handle_list); | |
2466 | } | |
2467 | } | |
2468 | } | |
2469 | ||
2470 | static void activate_bit_delay(raid5_conf_t *conf) | |
2471 | { | |
2472 | /* device_lock is held */ | |
2473 | struct list_head head; | |
2474 | list_add(&head, &conf->bitmap_list); | |
2475 | list_del_init(&conf->bitmap_list); | |
2476 | while (!list_empty(&head)) { | |
2477 | struct stripe_head *sh = list_entry(head.next, struct stripe_head, lru); | |
2478 | list_del_init(&sh->lru); | |
2479 | atomic_inc(&sh->count); | |
2480 | __release_stripe(conf, sh); | |
2481 | } | |
2482 | } | |
2483 | ||
2484 | static void unplug_slaves(mddev_t *mddev) | |
2485 | { | |
2486 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
2487 | int i; | |
2488 | ||
2489 | rcu_read_lock(); | |
2490 | for (i=0; i<mddev->raid_disks; i++) { | |
2491 | mdk_rdev_t *rdev = rcu_dereference(conf->disks[i].rdev); | |
2492 | if (rdev && !test_bit(Faulty, &rdev->flags) && atomic_read(&rdev->nr_pending)) { | |
2493 | request_queue_t *r_queue = bdev_get_queue(rdev->bdev); | |
2494 | ||
2495 | atomic_inc(&rdev->nr_pending); | |
2496 | rcu_read_unlock(); | |
2497 | ||
2498 | if (r_queue->unplug_fn) | |
2499 | r_queue->unplug_fn(r_queue); | |
2500 | ||
2501 | rdev_dec_pending(rdev, mddev); | |
2502 | rcu_read_lock(); | |
2503 | } | |
2504 | } | |
2505 | rcu_read_unlock(); | |
2506 | } | |
2507 | ||
2508 | static void raid5_unplug_device(request_queue_t *q) | |
2509 | { | |
2510 | mddev_t *mddev = q->queuedata; | |
2511 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
2512 | unsigned long flags; | |
2513 | ||
2514 | spin_lock_irqsave(&conf->device_lock, flags); | |
2515 | ||
2516 | if (blk_remove_plug(q)) { | |
2517 | conf->seq_flush++; | |
2518 | raid5_activate_delayed(conf); | |
72626685 | 2519 | } |
1da177e4 LT |
2520 | md_wakeup_thread(mddev->thread); |
2521 | ||
2522 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
2523 | ||
2524 | unplug_slaves(mddev); | |
2525 | } | |
2526 | ||
2527 | static int raid5_issue_flush(request_queue_t *q, struct gendisk *disk, | |
2528 | sector_t *error_sector) | |
2529 | { | |
2530 | mddev_t *mddev = q->queuedata; | |
2531 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
2532 | int i, ret = 0; | |
2533 | ||
2534 | rcu_read_lock(); | |
2535 | for (i=0; i<mddev->raid_disks && ret == 0; i++) { | |
d6065f7b | 2536 | mdk_rdev_t *rdev = rcu_dereference(conf->disks[i].rdev); |
b2d444d7 | 2537 | if (rdev && !test_bit(Faulty, &rdev->flags)) { |
1da177e4 LT |
2538 | struct block_device *bdev = rdev->bdev; |
2539 | request_queue_t *r_queue = bdev_get_queue(bdev); | |
2540 | ||
2541 | if (!r_queue->issue_flush_fn) | |
2542 | ret = -EOPNOTSUPP; | |
2543 | else { | |
2544 | atomic_inc(&rdev->nr_pending); | |
2545 | rcu_read_unlock(); | |
2546 | ret = r_queue->issue_flush_fn(r_queue, bdev->bd_disk, | |
2547 | error_sector); | |
2548 | rdev_dec_pending(rdev, mddev); | |
2549 | rcu_read_lock(); | |
2550 | } | |
2551 | } | |
2552 | } | |
2553 | rcu_read_unlock(); | |
2554 | return ret; | |
2555 | } | |
2556 | ||
2557 | static inline void raid5_plug_device(raid5_conf_t *conf) | |
2558 | { | |
2559 | spin_lock_irq(&conf->device_lock); | |
2560 | blk_plug_device(conf->mddev->queue); | |
2561 | spin_unlock_irq(&conf->device_lock); | |
2562 | } | |
2563 | ||
7ecaa1e6 | 2564 | static int make_request(request_queue_t *q, struct bio * bi) |
1da177e4 LT |
2565 | { |
2566 | mddev_t *mddev = q->queuedata; | |
2567 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
1da177e4 LT |
2568 | unsigned int dd_idx, pd_idx; |
2569 | sector_t new_sector; | |
2570 | sector_t logical_sector, last_sector; | |
2571 | struct stripe_head *sh; | |
a362357b | 2572 | const int rw = bio_data_dir(bi); |
f6344757 | 2573 | int remaining; |
1da177e4 | 2574 | |
e5dcdd80 N |
2575 | if (unlikely(bio_barrier(bi))) { |
2576 | bio_endio(bi, bi->bi_size, -EOPNOTSUPP); | |
2577 | return 0; | |
2578 | } | |
2579 | ||
3d310eb7 | 2580 | md_write_start(mddev, bi); |
06d91a5f | 2581 | |
a362357b JA |
2582 | disk_stat_inc(mddev->gendisk, ios[rw]); |
2583 | disk_stat_add(mddev->gendisk, sectors[rw], bio_sectors(bi)); | |
1da177e4 LT |
2584 | |
2585 | logical_sector = bi->bi_sector & ~((sector_t)STRIPE_SECTORS-1); | |
2586 | last_sector = bi->bi_sector + (bi->bi_size>>9); | |
2587 | bi->bi_next = NULL; | |
2588 | bi->bi_phys_segments = 1; /* over-loaded to count active stripes */ | |
06d91a5f | 2589 | |
1da177e4 LT |
2590 | for (;logical_sector < last_sector; logical_sector += STRIPE_SECTORS) { |
2591 | DEFINE_WAIT(w); | |
16a53ecc | 2592 | int disks, data_disks; |
b578d55f | 2593 | |
7ecaa1e6 | 2594 | retry: |
b578d55f | 2595 | prepare_to_wait(&conf->wait_for_overlap, &w, TASK_UNINTERRUPTIBLE); |
7ecaa1e6 N |
2596 | if (likely(conf->expand_progress == MaxSector)) |
2597 | disks = conf->raid_disks; | |
2598 | else { | |
df8e7f76 N |
2599 | /* spinlock is needed as expand_progress may be |
2600 | * 64bit on a 32bit platform, and so it might be | |
2601 | * possible to see a half-updated value | |
2602 | * Ofcourse expand_progress could change after | |
2603 | * the lock is dropped, so once we get a reference | |
2604 | * to the stripe that we think it is, we will have | |
2605 | * to check again. | |
2606 | */ | |
7ecaa1e6 N |
2607 | spin_lock_irq(&conf->device_lock); |
2608 | disks = conf->raid_disks; | |
2609 | if (logical_sector >= conf->expand_progress) | |
2610 | disks = conf->previous_raid_disks; | |
b578d55f N |
2611 | else { |
2612 | if (logical_sector >= conf->expand_lo) { | |
2613 | spin_unlock_irq(&conf->device_lock); | |
2614 | schedule(); | |
2615 | goto retry; | |
2616 | } | |
2617 | } | |
7ecaa1e6 N |
2618 | spin_unlock_irq(&conf->device_lock); |
2619 | } | |
16a53ecc N |
2620 | data_disks = disks - conf->max_degraded; |
2621 | ||
2622 | new_sector = raid5_compute_sector(logical_sector, disks, data_disks, | |
7ecaa1e6 | 2623 | &dd_idx, &pd_idx, conf); |
1da177e4 LT |
2624 | PRINTK("raid5: make_request, sector %llu logical %llu\n", |
2625 | (unsigned long long)new_sector, | |
2626 | (unsigned long long)logical_sector); | |
2627 | ||
7ecaa1e6 | 2628 | sh = get_active_stripe(conf, new_sector, disks, pd_idx, (bi->bi_rw&RWA_MASK)); |
1da177e4 | 2629 | if (sh) { |
7ecaa1e6 N |
2630 | if (unlikely(conf->expand_progress != MaxSector)) { |
2631 | /* expansion might have moved on while waiting for a | |
df8e7f76 N |
2632 | * stripe, so we must do the range check again. |
2633 | * Expansion could still move past after this | |
2634 | * test, but as we are holding a reference to | |
2635 | * 'sh', we know that if that happens, | |
2636 | * STRIPE_EXPANDING will get set and the expansion | |
2637 | * won't proceed until we finish with the stripe. | |
7ecaa1e6 N |
2638 | */ |
2639 | int must_retry = 0; | |
2640 | spin_lock_irq(&conf->device_lock); | |
2641 | if (logical_sector < conf->expand_progress && | |
2642 | disks == conf->previous_raid_disks) | |
2643 | /* mismatch, need to try again */ | |
2644 | must_retry = 1; | |
2645 | spin_unlock_irq(&conf->device_lock); | |
2646 | if (must_retry) { | |
2647 | release_stripe(sh); | |
2648 | goto retry; | |
2649 | } | |
2650 | } | |
e464eafd N |
2651 | /* FIXME what if we get a false positive because these |
2652 | * are being updated. | |
2653 | */ | |
2654 | if (logical_sector >= mddev->suspend_lo && | |
2655 | logical_sector < mddev->suspend_hi) { | |
2656 | release_stripe(sh); | |
2657 | schedule(); | |
2658 | goto retry; | |
2659 | } | |
7ecaa1e6 N |
2660 | |
2661 | if (test_bit(STRIPE_EXPANDING, &sh->state) || | |
2662 | !add_stripe_bio(sh, bi, dd_idx, (bi->bi_rw&RW_MASK))) { | |
2663 | /* Stripe is busy expanding or | |
2664 | * add failed due to overlap. Flush everything | |
1da177e4 LT |
2665 | * and wait a while |
2666 | */ | |
2667 | raid5_unplug_device(mddev->queue); | |
2668 | release_stripe(sh); | |
2669 | schedule(); | |
2670 | goto retry; | |
2671 | } | |
2672 | finish_wait(&conf->wait_for_overlap, &w); | |
2673 | raid5_plug_device(conf); | |
16a53ecc | 2674 | handle_stripe(sh, NULL); |
1da177e4 | 2675 | release_stripe(sh); |
1da177e4 LT |
2676 | } else { |
2677 | /* cannot get stripe for read-ahead, just give-up */ | |
2678 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
2679 | finish_wait(&conf->wait_for_overlap, &w); | |
2680 | break; | |
2681 | } | |
2682 | ||
2683 | } | |
2684 | spin_lock_irq(&conf->device_lock); | |
f6344757 N |
2685 | remaining = --bi->bi_phys_segments; |
2686 | spin_unlock_irq(&conf->device_lock); | |
2687 | if (remaining == 0) { | |
1da177e4 LT |
2688 | int bytes = bi->bi_size; |
2689 | ||
16a53ecc | 2690 | if ( rw == WRITE ) |
1da177e4 LT |
2691 | md_write_end(mddev); |
2692 | bi->bi_size = 0; | |
2693 | bi->bi_end_io(bi, bytes, 0); | |
2694 | } | |
1da177e4 LT |
2695 | return 0; |
2696 | } | |
2697 | ||
52c03291 | 2698 | static sector_t reshape_request(mddev_t *mddev, sector_t sector_nr, int *skipped) |
1da177e4 | 2699 | { |
52c03291 N |
2700 | /* reshaping is quite different to recovery/resync so it is |
2701 | * handled quite separately ... here. | |
2702 | * | |
2703 | * On each call to sync_request, we gather one chunk worth of | |
2704 | * destination stripes and flag them as expanding. | |
2705 | * Then we find all the source stripes and request reads. | |
2706 | * As the reads complete, handle_stripe will copy the data | |
2707 | * into the destination stripe and release that stripe. | |
2708 | */ | |
1da177e4 LT |
2709 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; |
2710 | struct stripe_head *sh; | |
ccfcc3c1 N |
2711 | int pd_idx; |
2712 | sector_t first_sector, last_sector; | |
52c03291 N |
2713 | int raid_disks; |
2714 | int data_disks; | |
2715 | int i; | |
2716 | int dd_idx; | |
2717 | sector_t writepos, safepos, gap; | |
2718 | ||
2719 | if (sector_nr == 0 && | |
2720 | conf->expand_progress != 0) { | |
2721 | /* restarting in the middle, skip the initial sectors */ | |
2722 | sector_nr = conf->expand_progress; | |
2723 | sector_div(sector_nr, conf->raid_disks-1); | |
2724 | *skipped = 1; | |
2725 | return sector_nr; | |
2726 | } | |
2727 | ||
2728 | /* we update the metadata when there is more than 3Meg | |
2729 | * in the block range (that is rather arbitrary, should | |
2730 | * probably be time based) or when the data about to be | |
2731 | * copied would over-write the source of the data at | |
2732 | * the front of the range. | |
2733 | * i.e. one new_stripe forward from expand_progress new_maps | |
2734 | * to after where expand_lo old_maps to | |
2735 | */ | |
2736 | writepos = conf->expand_progress + | |
2737 | conf->chunk_size/512*(conf->raid_disks-1); | |
2738 | sector_div(writepos, conf->raid_disks-1); | |
2739 | safepos = conf->expand_lo; | |
2740 | sector_div(safepos, conf->previous_raid_disks-1); | |
2741 | gap = conf->expand_progress - conf->expand_lo; | |
2742 | ||
2743 | if (writepos >= safepos || | |
2744 | gap > (conf->raid_disks-1)*3000*2 /*3Meg*/) { | |
2745 | /* Cannot proceed until we've updated the superblock... */ | |
2746 | wait_event(conf->wait_for_overlap, | |
2747 | atomic_read(&conf->reshape_stripes)==0); | |
2748 | mddev->reshape_position = conf->expand_progress; | |
2749 | mddev->sb_dirty = 1; | |
2750 | md_wakeup_thread(mddev->thread); | |
2751 | wait_event(mddev->sb_wait, mddev->sb_dirty == 0 || | |
2752 | kthread_should_stop()); | |
2753 | spin_lock_irq(&conf->device_lock); | |
2754 | conf->expand_lo = mddev->reshape_position; | |
2755 | spin_unlock_irq(&conf->device_lock); | |
2756 | wake_up(&conf->wait_for_overlap); | |
2757 | } | |
2758 | ||
2759 | for (i=0; i < conf->chunk_size/512; i+= STRIPE_SECTORS) { | |
2760 | int j; | |
2761 | int skipped = 0; | |
2762 | pd_idx = stripe_to_pdidx(sector_nr+i, conf, conf->raid_disks); | |
2763 | sh = get_active_stripe(conf, sector_nr+i, | |
2764 | conf->raid_disks, pd_idx, 0); | |
2765 | set_bit(STRIPE_EXPANDING, &sh->state); | |
2766 | atomic_inc(&conf->reshape_stripes); | |
2767 | /* If any of this stripe is beyond the end of the old | |
2768 | * array, then we need to zero those blocks | |
2769 | */ | |
2770 | for (j=sh->disks; j--;) { | |
2771 | sector_t s; | |
2772 | if (j == sh->pd_idx) | |
2773 | continue; | |
2774 | s = compute_blocknr(sh, j); | |
2775 | if (s < (mddev->array_size<<1)) { | |
2776 | skipped = 1; | |
2777 | continue; | |
2778 | } | |
2779 | memset(page_address(sh->dev[j].page), 0, STRIPE_SIZE); | |
2780 | set_bit(R5_Expanded, &sh->dev[j].flags); | |
2781 | set_bit(R5_UPTODATE, &sh->dev[j].flags); | |
2782 | } | |
2783 | if (!skipped) { | |
2784 | set_bit(STRIPE_EXPAND_READY, &sh->state); | |
2785 | set_bit(STRIPE_HANDLE, &sh->state); | |
2786 | } | |
2787 | release_stripe(sh); | |
2788 | } | |
2789 | spin_lock_irq(&conf->device_lock); | |
2790 | conf->expand_progress = (sector_nr + i)*(conf->raid_disks-1); | |
2791 | spin_unlock_irq(&conf->device_lock); | |
2792 | /* Ok, those stripe are ready. We can start scheduling | |
2793 | * reads on the source stripes. | |
2794 | * The source stripes are determined by mapping the first and last | |
2795 | * block on the destination stripes. | |
2796 | */ | |
2797 | raid_disks = conf->previous_raid_disks; | |
2798 | data_disks = raid_disks - 1; | |
2799 | first_sector = | |
2800 | raid5_compute_sector(sector_nr*(conf->raid_disks-1), | |
2801 | raid_disks, data_disks, | |
2802 | &dd_idx, &pd_idx, conf); | |
2803 | last_sector = | |
2804 | raid5_compute_sector((sector_nr+conf->chunk_size/512) | |
2805 | *(conf->raid_disks-1) -1, | |
2806 | raid_disks, data_disks, | |
2807 | &dd_idx, &pd_idx, conf); | |
2808 | if (last_sector >= (mddev->size<<1)) | |
2809 | last_sector = (mddev->size<<1)-1; | |
2810 | while (first_sector <= last_sector) { | |
2811 | pd_idx = stripe_to_pdidx(first_sector, conf, conf->previous_raid_disks); | |
2812 | sh = get_active_stripe(conf, first_sector, | |
2813 | conf->previous_raid_disks, pd_idx, 0); | |
2814 | set_bit(STRIPE_EXPAND_SOURCE, &sh->state); | |
2815 | set_bit(STRIPE_HANDLE, &sh->state); | |
2816 | release_stripe(sh); | |
2817 | first_sector += STRIPE_SECTORS; | |
2818 | } | |
2819 | return conf->chunk_size>>9; | |
2820 | } | |
2821 | ||
2822 | /* FIXME go_faster isn't used */ | |
2823 | static inline sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, int go_faster) | |
2824 | { | |
2825 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; | |
2826 | struct stripe_head *sh; | |
2827 | int pd_idx; | |
1da177e4 | 2828 | int raid_disks = conf->raid_disks; |
72626685 N |
2829 | sector_t max_sector = mddev->size << 1; |
2830 | int sync_blocks; | |
16a53ecc N |
2831 | int still_degraded = 0; |
2832 | int i; | |
1da177e4 | 2833 | |
72626685 | 2834 | if (sector_nr >= max_sector) { |
1da177e4 LT |
2835 | /* just being told to finish up .. nothing much to do */ |
2836 | unplug_slaves(mddev); | |
29269553 N |
2837 | if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) { |
2838 | end_reshape(conf); | |
2839 | return 0; | |
2840 | } | |
72626685 N |
2841 | |
2842 | if (mddev->curr_resync < max_sector) /* aborted */ | |
2843 | bitmap_end_sync(mddev->bitmap, mddev->curr_resync, | |
2844 | &sync_blocks, 1); | |
16a53ecc | 2845 | else /* completed sync */ |
72626685 N |
2846 | conf->fullsync = 0; |
2847 | bitmap_close_sync(mddev->bitmap); | |
2848 | ||
1da177e4 LT |
2849 | return 0; |
2850 | } | |
ccfcc3c1 | 2851 | |
52c03291 N |
2852 | if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) |
2853 | return reshape_request(mddev, sector_nr, skipped); | |
f6705578 | 2854 | |
16a53ecc | 2855 | /* if there is too many failed drives and we are trying |
1da177e4 LT |
2856 | * to resync, then assert that we are finished, because there is |
2857 | * nothing we can do. | |
2858 | */ | |
3285edf1 | 2859 | if (mddev->degraded >= conf->max_degraded && |
16a53ecc | 2860 | test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) { |
57afd89f N |
2861 | sector_t rv = (mddev->size << 1) - sector_nr; |
2862 | *skipped = 1; | |
1da177e4 LT |
2863 | return rv; |
2864 | } | |
72626685 | 2865 | if (!bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, 1) && |
3855ad9f | 2866 | !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) && |
72626685 N |
2867 | !conf->fullsync && sync_blocks >= STRIPE_SECTORS) { |
2868 | /* we can skip this block, and probably more */ | |
2869 | sync_blocks /= STRIPE_SECTORS; | |
2870 | *skipped = 1; | |
2871 | return sync_blocks * STRIPE_SECTORS; /* keep things rounded to whole stripes */ | |
2872 | } | |
1da177e4 | 2873 | |
ccfcc3c1 | 2874 | pd_idx = stripe_to_pdidx(sector_nr, conf, raid_disks); |
7ecaa1e6 | 2875 | sh = get_active_stripe(conf, sector_nr, raid_disks, pd_idx, 1); |
1da177e4 | 2876 | if (sh == NULL) { |
7ecaa1e6 | 2877 | sh = get_active_stripe(conf, sector_nr, raid_disks, pd_idx, 0); |
1da177e4 | 2878 | /* make sure we don't swamp the stripe cache if someone else |
16a53ecc | 2879 | * is trying to get access |
1da177e4 | 2880 | */ |
66c006a5 | 2881 | schedule_timeout_uninterruptible(1); |
1da177e4 | 2882 | } |
16a53ecc N |
2883 | /* Need to check if array will still be degraded after recovery/resync |
2884 | * We don't need to check the 'failed' flag as when that gets set, | |
2885 | * recovery aborts. | |
2886 | */ | |
2887 | for (i=0; i<mddev->raid_disks; i++) | |
2888 | if (conf->disks[i].rdev == NULL) | |
2889 | still_degraded = 1; | |
2890 | ||
2891 | bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, still_degraded); | |
2892 | ||
2893 | spin_lock(&sh->lock); | |
1da177e4 LT |
2894 | set_bit(STRIPE_SYNCING, &sh->state); |
2895 | clear_bit(STRIPE_INSYNC, &sh->state); | |
2896 | spin_unlock(&sh->lock); | |
2897 | ||
16a53ecc | 2898 | handle_stripe(sh, NULL); |
1da177e4 LT |
2899 | release_stripe(sh); |
2900 | ||
2901 | return STRIPE_SECTORS; | |
2902 | } | |
2903 | ||
2904 | /* | |
2905 | * This is our raid5 kernel thread. | |
2906 | * | |
2907 | * We scan the hash table for stripes which can be handled now. | |
2908 | * During the scan, completed stripes are saved for us by the interrupt | |
2909 | * handler, so that they will not have to wait for our next wakeup. | |
2910 | */ | |
2911 | static void raid5d (mddev_t *mddev) | |
2912 | { | |
2913 | struct stripe_head *sh; | |
2914 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
2915 | int handled; | |
2916 | ||
2917 | PRINTK("+++ raid5d active\n"); | |
2918 | ||
2919 | md_check_recovery(mddev); | |
1da177e4 LT |
2920 | |
2921 | handled = 0; | |
2922 | spin_lock_irq(&conf->device_lock); | |
2923 | while (1) { | |
2924 | struct list_head *first; | |
2925 | ||
72626685 N |
2926 | if (conf->seq_flush - conf->seq_write > 0) { |
2927 | int seq = conf->seq_flush; | |
700e432d | 2928 | spin_unlock_irq(&conf->device_lock); |
72626685 | 2929 | bitmap_unplug(mddev->bitmap); |
700e432d | 2930 | spin_lock_irq(&conf->device_lock); |
72626685 N |
2931 | conf->seq_write = seq; |
2932 | activate_bit_delay(conf); | |
2933 | } | |
2934 | ||
1da177e4 LT |
2935 | if (list_empty(&conf->handle_list) && |
2936 | atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD && | |
2937 | !blk_queue_plugged(mddev->queue) && | |
2938 | !list_empty(&conf->delayed_list)) | |
2939 | raid5_activate_delayed(conf); | |
2940 | ||
2941 | if (list_empty(&conf->handle_list)) | |
2942 | break; | |
2943 | ||
2944 | first = conf->handle_list.next; | |
2945 | sh = list_entry(first, struct stripe_head, lru); | |
2946 | ||
2947 | list_del_init(first); | |
2948 | atomic_inc(&sh->count); | |
78bafebd | 2949 | BUG_ON(atomic_read(&sh->count)!= 1); |
1da177e4 LT |
2950 | spin_unlock_irq(&conf->device_lock); |
2951 | ||
2952 | handled++; | |
16a53ecc | 2953 | handle_stripe(sh, conf->spare_page); |
1da177e4 LT |
2954 | release_stripe(sh); |
2955 | ||
2956 | spin_lock_irq(&conf->device_lock); | |
2957 | } | |
2958 | PRINTK("%d stripes handled\n", handled); | |
2959 | ||
2960 | spin_unlock_irq(&conf->device_lock); | |
2961 | ||
2962 | unplug_slaves(mddev); | |
2963 | ||
2964 | PRINTK("--- raid5d inactive\n"); | |
2965 | } | |
2966 | ||
3f294f4f | 2967 | static ssize_t |
007583c9 | 2968 | raid5_show_stripe_cache_size(mddev_t *mddev, char *page) |
3f294f4f | 2969 | { |
007583c9 | 2970 | raid5_conf_t *conf = mddev_to_conf(mddev); |
96de1e66 N |
2971 | if (conf) |
2972 | return sprintf(page, "%d\n", conf->max_nr_stripes); | |
2973 | else | |
2974 | return 0; | |
3f294f4f N |
2975 | } |
2976 | ||
2977 | static ssize_t | |
007583c9 | 2978 | raid5_store_stripe_cache_size(mddev_t *mddev, const char *page, size_t len) |
3f294f4f | 2979 | { |
007583c9 | 2980 | raid5_conf_t *conf = mddev_to_conf(mddev); |
3f294f4f N |
2981 | char *end; |
2982 | int new; | |
2983 | if (len >= PAGE_SIZE) | |
2984 | return -EINVAL; | |
96de1e66 N |
2985 | if (!conf) |
2986 | return -ENODEV; | |
3f294f4f N |
2987 | |
2988 | new = simple_strtoul(page, &end, 10); | |
2989 | if (!*page || (*end && *end != '\n') ) | |
2990 | return -EINVAL; | |
2991 | if (new <= 16 || new > 32768) | |
2992 | return -EINVAL; | |
2993 | while (new < conf->max_nr_stripes) { | |
2994 | if (drop_one_stripe(conf)) | |
2995 | conf->max_nr_stripes--; | |
2996 | else | |
2997 | break; | |
2998 | } | |
2999 | while (new > conf->max_nr_stripes) { | |
3000 | if (grow_one_stripe(conf)) | |
3001 | conf->max_nr_stripes++; | |
3002 | else break; | |
3003 | } | |
3004 | return len; | |
3005 | } | |
007583c9 | 3006 | |
96de1e66 N |
3007 | static struct md_sysfs_entry |
3008 | raid5_stripecache_size = __ATTR(stripe_cache_size, S_IRUGO | S_IWUSR, | |
3009 | raid5_show_stripe_cache_size, | |
3010 | raid5_store_stripe_cache_size); | |
3f294f4f N |
3011 | |
3012 | static ssize_t | |
96de1e66 | 3013 | stripe_cache_active_show(mddev_t *mddev, char *page) |
3f294f4f | 3014 | { |
007583c9 | 3015 | raid5_conf_t *conf = mddev_to_conf(mddev); |
96de1e66 N |
3016 | if (conf) |
3017 | return sprintf(page, "%d\n", atomic_read(&conf->active_stripes)); | |
3018 | else | |
3019 | return 0; | |
3f294f4f N |
3020 | } |
3021 | ||
96de1e66 N |
3022 | static struct md_sysfs_entry |
3023 | raid5_stripecache_active = __ATTR_RO(stripe_cache_active); | |
3f294f4f | 3024 | |
007583c9 | 3025 | static struct attribute *raid5_attrs[] = { |
3f294f4f N |
3026 | &raid5_stripecache_size.attr, |
3027 | &raid5_stripecache_active.attr, | |
3028 | NULL, | |
3029 | }; | |
007583c9 N |
3030 | static struct attribute_group raid5_attrs_group = { |
3031 | .name = NULL, | |
3032 | .attrs = raid5_attrs, | |
3f294f4f N |
3033 | }; |
3034 | ||
72626685 | 3035 | static int run(mddev_t *mddev) |
1da177e4 LT |
3036 | { |
3037 | raid5_conf_t *conf; | |
3038 | int raid_disk, memory; | |
3039 | mdk_rdev_t *rdev; | |
3040 | struct disk_info *disk; | |
3041 | struct list_head *tmp; | |
3042 | ||
16a53ecc N |
3043 | if (mddev->level != 5 && mddev->level != 4 && mddev->level != 6) { |
3044 | printk(KERN_ERR "raid5: %s: raid level not set to 4/5/6 (%d)\n", | |
14f8d26b | 3045 | mdname(mddev), mddev->level); |
1da177e4 LT |
3046 | return -EIO; |
3047 | } | |
3048 | ||
f6705578 N |
3049 | if (mddev->reshape_position != MaxSector) { |
3050 | /* Check that we can continue the reshape. | |
3051 | * Currently only disks can change, it must | |
3052 | * increase, and we must be past the point where | |
3053 | * a stripe over-writes itself | |
3054 | */ | |
3055 | sector_t here_new, here_old; | |
3056 | int old_disks; | |
3057 | ||
3058 | if (mddev->new_level != mddev->level || | |
3059 | mddev->new_layout != mddev->layout || | |
3060 | mddev->new_chunk != mddev->chunk_size) { | |
3061 | printk(KERN_ERR "raid5: %s: unsupported reshape required - aborting.\n", | |
3062 | mdname(mddev)); | |
3063 | return -EINVAL; | |
3064 | } | |
3065 | if (mddev->delta_disks <= 0) { | |
3066 | printk(KERN_ERR "raid5: %s: unsupported reshape (reduce disks) required - aborting.\n", | |
3067 | mdname(mddev)); | |
3068 | return -EINVAL; | |
3069 | } | |
3070 | old_disks = mddev->raid_disks - mddev->delta_disks; | |
3071 | /* reshape_position must be on a new-stripe boundary, and one | |
3072 | * further up in new geometry must map after here in old geometry. | |
3073 | */ | |
3074 | here_new = mddev->reshape_position; | |
3075 | if (sector_div(here_new, (mddev->chunk_size>>9)*(mddev->raid_disks-1))) { | |
3076 | printk(KERN_ERR "raid5: reshape_position not on a stripe boundary\n"); | |
3077 | return -EINVAL; | |
3078 | } | |
3079 | /* here_new is the stripe we will write to */ | |
3080 | here_old = mddev->reshape_position; | |
3081 | sector_div(here_old, (mddev->chunk_size>>9)*(old_disks-1)); | |
3082 | /* here_old is the first stripe that we might need to read from */ | |
3083 | if (here_new >= here_old) { | |
3084 | /* Reading from the same stripe as writing to - bad */ | |
3085 | printk(KERN_ERR "raid5: reshape_position too early for auto-recovery - aborting.\n"); | |
3086 | return -EINVAL; | |
3087 | } | |
3088 | printk(KERN_INFO "raid5: reshape will continue\n"); | |
3089 | /* OK, we should be able to continue; */ | |
3090 | } | |
3091 | ||
3092 | ||
b55e6bfc | 3093 | mddev->private = kzalloc(sizeof (raid5_conf_t), GFP_KERNEL); |
1da177e4 LT |
3094 | if ((conf = mddev->private) == NULL) |
3095 | goto abort; | |
f6705578 N |
3096 | if (mddev->reshape_position == MaxSector) { |
3097 | conf->previous_raid_disks = conf->raid_disks = mddev->raid_disks; | |
3098 | } else { | |
3099 | conf->raid_disks = mddev->raid_disks; | |
3100 | conf->previous_raid_disks = mddev->raid_disks - mddev->delta_disks; | |
3101 | } | |
3102 | ||
3103 | conf->disks = kzalloc(conf->raid_disks * sizeof(struct disk_info), | |
b55e6bfc N |
3104 | GFP_KERNEL); |
3105 | if (!conf->disks) | |
3106 | goto abort; | |
9ffae0cf | 3107 | |
1da177e4 LT |
3108 | conf->mddev = mddev; |
3109 | ||
fccddba0 | 3110 | if ((conf->stripe_hashtbl = kzalloc(PAGE_SIZE, GFP_KERNEL)) == NULL) |
1da177e4 | 3111 | goto abort; |
1da177e4 | 3112 | |
16a53ecc N |
3113 | if (mddev->level == 6) { |
3114 | conf->spare_page = alloc_page(GFP_KERNEL); | |
3115 | if (!conf->spare_page) | |
3116 | goto abort; | |
3117 | } | |
1da177e4 LT |
3118 | spin_lock_init(&conf->device_lock); |
3119 | init_waitqueue_head(&conf->wait_for_stripe); | |
3120 | init_waitqueue_head(&conf->wait_for_overlap); | |
3121 | INIT_LIST_HEAD(&conf->handle_list); | |
3122 | INIT_LIST_HEAD(&conf->delayed_list); | |
72626685 | 3123 | INIT_LIST_HEAD(&conf->bitmap_list); |
1da177e4 LT |
3124 | INIT_LIST_HEAD(&conf->inactive_list); |
3125 | atomic_set(&conf->active_stripes, 0); | |
3126 | atomic_set(&conf->preread_active_stripes, 0); | |
3127 | ||
1da177e4 LT |
3128 | PRINTK("raid5: run(%s) called.\n", mdname(mddev)); |
3129 | ||
3130 | ITERATE_RDEV(mddev,rdev,tmp) { | |
3131 | raid_disk = rdev->raid_disk; | |
f6705578 | 3132 | if (raid_disk >= conf->raid_disks |
1da177e4 LT |
3133 | || raid_disk < 0) |
3134 | continue; | |
3135 | disk = conf->disks + raid_disk; | |
3136 | ||
3137 | disk->rdev = rdev; | |
3138 | ||
b2d444d7 | 3139 | if (test_bit(In_sync, &rdev->flags)) { |
1da177e4 LT |
3140 | char b[BDEVNAME_SIZE]; |
3141 | printk(KERN_INFO "raid5: device %s operational as raid" | |
3142 | " disk %d\n", bdevname(rdev->bdev,b), | |
3143 | raid_disk); | |
3144 | conf->working_disks++; | |
3145 | } | |
3146 | } | |
3147 | ||
1da177e4 | 3148 | /* |
16a53ecc | 3149 | * 0 for a fully functional array, 1 or 2 for a degraded array. |
1da177e4 LT |
3150 | */ |
3151 | mddev->degraded = conf->failed_disks = conf->raid_disks - conf->working_disks; | |
3152 | conf->mddev = mddev; | |
3153 | conf->chunk_size = mddev->chunk_size; | |
3154 | conf->level = mddev->level; | |
16a53ecc N |
3155 | if (conf->level == 6) |
3156 | conf->max_degraded = 2; | |
3157 | else | |
3158 | conf->max_degraded = 1; | |
1da177e4 LT |
3159 | conf->algorithm = mddev->layout; |
3160 | conf->max_nr_stripes = NR_STRIPES; | |
f6705578 | 3161 | conf->expand_progress = mddev->reshape_position; |
1da177e4 LT |
3162 | |
3163 | /* device size must be a multiple of chunk size */ | |
3164 | mddev->size &= ~(mddev->chunk_size/1024 -1); | |
b1581566 | 3165 | mddev->resync_max_sectors = mddev->size << 1; |
1da177e4 | 3166 | |
16a53ecc N |
3167 | if (conf->level == 6 && conf->raid_disks < 4) { |
3168 | printk(KERN_ERR "raid6: not enough configured devices for %s (%d, minimum 4)\n", | |
3169 | mdname(mddev), conf->raid_disks); | |
3170 | goto abort; | |
3171 | } | |
1da177e4 LT |
3172 | if (!conf->chunk_size || conf->chunk_size % 4) { |
3173 | printk(KERN_ERR "raid5: invalid chunk size %d for %s\n", | |
3174 | conf->chunk_size, mdname(mddev)); | |
3175 | goto abort; | |
3176 | } | |
3177 | if (conf->algorithm > ALGORITHM_RIGHT_SYMMETRIC) { | |
3178 | printk(KERN_ERR | |
3179 | "raid5: unsupported parity algorithm %d for %s\n", | |
3180 | conf->algorithm, mdname(mddev)); | |
3181 | goto abort; | |
3182 | } | |
16a53ecc | 3183 | if (mddev->degraded > conf->max_degraded) { |
1da177e4 LT |
3184 | printk(KERN_ERR "raid5: not enough operational devices for %s" |
3185 | " (%d/%d failed)\n", | |
3186 | mdname(mddev), conf->failed_disks, conf->raid_disks); | |
3187 | goto abort; | |
3188 | } | |
3189 | ||
16a53ecc | 3190 | if (mddev->degraded > 0 && |
1da177e4 | 3191 | mddev->recovery_cp != MaxSector) { |
6ff8d8ec N |
3192 | if (mddev->ok_start_degraded) |
3193 | printk(KERN_WARNING | |
3194 | "raid5: starting dirty degraded array: %s" | |
3195 | "- data corruption possible.\n", | |
3196 | mdname(mddev)); | |
3197 | else { | |
3198 | printk(KERN_ERR | |
3199 | "raid5: cannot start dirty degraded array for %s\n", | |
3200 | mdname(mddev)); | |
3201 | goto abort; | |
3202 | } | |
1da177e4 LT |
3203 | } |
3204 | ||
3205 | { | |
3206 | mddev->thread = md_register_thread(raid5d, mddev, "%s_raid5"); | |
3207 | if (!mddev->thread) { | |
3208 | printk(KERN_ERR | |
3209 | "raid5: couldn't allocate thread for %s\n", | |
3210 | mdname(mddev)); | |
3211 | goto abort; | |
3212 | } | |
3213 | } | |
5036805b | 3214 | memory = conf->max_nr_stripes * (sizeof(struct stripe_head) + |
1da177e4 LT |
3215 | conf->raid_disks * ((sizeof(struct bio) + PAGE_SIZE))) / 1024; |
3216 | if (grow_stripes(conf, conf->max_nr_stripes)) { | |
3217 | printk(KERN_ERR | |
3218 | "raid5: couldn't allocate %dkB for buffers\n", memory); | |
3219 | shrink_stripes(conf); | |
3220 | md_unregister_thread(mddev->thread); | |
3221 | goto abort; | |
3222 | } else | |
3223 | printk(KERN_INFO "raid5: allocated %dkB for %s\n", | |
3224 | memory, mdname(mddev)); | |
3225 | ||
3226 | if (mddev->degraded == 0) | |
3227 | printk("raid5: raid level %d set %s active with %d out of %d" | |
3228 | " devices, algorithm %d\n", conf->level, mdname(mddev), | |
3229 | mddev->raid_disks-mddev->degraded, mddev->raid_disks, | |
3230 | conf->algorithm); | |
3231 | else | |
3232 | printk(KERN_ALERT "raid5: raid level %d set %s active with %d" | |
3233 | " out of %d devices, algorithm %d\n", conf->level, | |
3234 | mdname(mddev), mddev->raid_disks - mddev->degraded, | |
3235 | mddev->raid_disks, conf->algorithm); | |
3236 | ||
3237 | print_raid5_conf(conf); | |
3238 | ||
f6705578 N |
3239 | if (conf->expand_progress != MaxSector) { |
3240 | printk("...ok start reshape thread\n"); | |
b578d55f | 3241 | conf->expand_lo = conf->expand_progress; |
f6705578 N |
3242 | atomic_set(&conf->reshape_stripes, 0); |
3243 | clear_bit(MD_RECOVERY_SYNC, &mddev->recovery); | |
3244 | clear_bit(MD_RECOVERY_CHECK, &mddev->recovery); | |
3245 | set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery); | |
3246 | set_bit(MD_RECOVERY_RUNNING, &mddev->recovery); | |
3247 | mddev->sync_thread = md_register_thread(md_do_sync, mddev, | |
3248 | "%s_reshape"); | |
f6705578 N |
3249 | } |
3250 | ||
1da177e4 | 3251 | /* read-ahead size must cover two whole stripes, which is |
16a53ecc | 3252 | * 2 * (datadisks) * chunksize where 'n' is the number of raid devices |
1da177e4 LT |
3253 | */ |
3254 | { | |
16a53ecc N |
3255 | int data_disks = conf->previous_raid_disks - conf->max_degraded; |
3256 | int stripe = data_disks * | |
8932c2e0 | 3257 | (mddev->chunk_size / PAGE_SIZE); |
1da177e4 LT |
3258 | if (mddev->queue->backing_dev_info.ra_pages < 2 * stripe) |
3259 | mddev->queue->backing_dev_info.ra_pages = 2 * stripe; | |
3260 | } | |
3261 | ||
3262 | /* Ok, everything is just fine now */ | |
007583c9 | 3263 | sysfs_create_group(&mddev->kobj, &raid5_attrs_group); |
7a5febe9 N |
3264 | |
3265 | mddev->queue->unplug_fn = raid5_unplug_device; | |
3266 | mddev->queue->issue_flush_fn = raid5_issue_flush; | |
16a53ecc N |
3267 | mddev->array_size = mddev->size * (conf->previous_raid_disks - |
3268 | conf->max_degraded); | |
7a5febe9 | 3269 | |
1da177e4 LT |
3270 | return 0; |
3271 | abort: | |
3272 | if (conf) { | |
3273 | print_raid5_conf(conf); | |
16a53ecc | 3274 | safe_put_page(conf->spare_page); |
b55e6bfc | 3275 | kfree(conf->disks); |
fccddba0 | 3276 | kfree(conf->stripe_hashtbl); |
1da177e4 LT |
3277 | kfree(conf); |
3278 | } | |
3279 | mddev->private = NULL; | |
3280 | printk(KERN_ALERT "raid5: failed to run raid set %s\n", mdname(mddev)); | |
3281 | return -EIO; | |
3282 | } | |
3283 | ||
3284 | ||
3285 | ||
3f294f4f | 3286 | static int stop(mddev_t *mddev) |
1da177e4 LT |
3287 | { |
3288 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; | |
3289 | ||
3290 | md_unregister_thread(mddev->thread); | |
3291 | mddev->thread = NULL; | |
3292 | shrink_stripes(conf); | |
fccddba0 | 3293 | kfree(conf->stripe_hashtbl); |
1da177e4 | 3294 | blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/ |
007583c9 | 3295 | sysfs_remove_group(&mddev->kobj, &raid5_attrs_group); |
b55e6bfc | 3296 | kfree(conf->disks); |
96de1e66 | 3297 | kfree(conf); |
1da177e4 LT |
3298 | mddev->private = NULL; |
3299 | return 0; | |
3300 | } | |
3301 | ||
3302 | #if RAID5_DEBUG | |
16a53ecc | 3303 | static void print_sh (struct seq_file *seq, struct stripe_head *sh) |
1da177e4 LT |
3304 | { |
3305 | int i; | |
3306 | ||
16a53ecc N |
3307 | seq_printf(seq, "sh %llu, pd_idx %d, state %ld.\n", |
3308 | (unsigned long long)sh->sector, sh->pd_idx, sh->state); | |
3309 | seq_printf(seq, "sh %llu, count %d.\n", | |
3310 | (unsigned long long)sh->sector, atomic_read(&sh->count)); | |
3311 | seq_printf(seq, "sh %llu, ", (unsigned long long)sh->sector); | |
7ecaa1e6 | 3312 | for (i = 0; i < sh->disks; i++) { |
16a53ecc N |
3313 | seq_printf(seq, "(cache%d: %p %ld) ", |
3314 | i, sh->dev[i].page, sh->dev[i].flags); | |
1da177e4 | 3315 | } |
16a53ecc | 3316 | seq_printf(seq, "\n"); |
1da177e4 LT |
3317 | } |
3318 | ||
16a53ecc | 3319 | static void printall (struct seq_file *seq, raid5_conf_t *conf) |
1da177e4 LT |
3320 | { |
3321 | struct stripe_head *sh; | |
fccddba0 | 3322 | struct hlist_node *hn; |
1da177e4 LT |
3323 | int i; |
3324 | ||
3325 | spin_lock_irq(&conf->device_lock); | |
3326 | for (i = 0; i < NR_HASH; i++) { | |
fccddba0 | 3327 | hlist_for_each_entry(sh, hn, &conf->stripe_hashtbl[i], hash) { |
1da177e4 LT |
3328 | if (sh->raid_conf != conf) |
3329 | continue; | |
16a53ecc | 3330 | print_sh(seq, sh); |
1da177e4 LT |
3331 | } |
3332 | } | |
3333 | spin_unlock_irq(&conf->device_lock); | |
3334 | } | |
3335 | #endif | |
3336 | ||
3337 | static void status (struct seq_file *seq, mddev_t *mddev) | |
3338 | { | |
3339 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; | |
3340 | int i; | |
3341 | ||
3342 | seq_printf (seq, " level %d, %dk chunk, algorithm %d", mddev->level, mddev->chunk_size >> 10, mddev->layout); | |
3343 | seq_printf (seq, " [%d/%d] [", conf->raid_disks, conf->working_disks); | |
3344 | for (i = 0; i < conf->raid_disks; i++) | |
3345 | seq_printf (seq, "%s", | |
3346 | conf->disks[i].rdev && | |
b2d444d7 | 3347 | test_bit(In_sync, &conf->disks[i].rdev->flags) ? "U" : "_"); |
1da177e4 LT |
3348 | seq_printf (seq, "]"); |
3349 | #if RAID5_DEBUG | |
16a53ecc N |
3350 | seq_printf (seq, "\n"); |
3351 | printall(seq, conf); | |
1da177e4 LT |
3352 | #endif |
3353 | } | |
3354 | ||
3355 | static void print_raid5_conf (raid5_conf_t *conf) | |
3356 | { | |
3357 | int i; | |
3358 | struct disk_info *tmp; | |
3359 | ||
3360 | printk("RAID5 conf printout:\n"); | |
3361 | if (!conf) { | |
3362 | printk("(conf==NULL)\n"); | |
3363 | return; | |
3364 | } | |
3365 | printk(" --- rd:%d wd:%d fd:%d\n", conf->raid_disks, | |
3366 | conf->working_disks, conf->failed_disks); | |
3367 | ||
3368 | for (i = 0; i < conf->raid_disks; i++) { | |
3369 | char b[BDEVNAME_SIZE]; | |
3370 | tmp = conf->disks + i; | |
3371 | if (tmp->rdev) | |
3372 | printk(" disk %d, o:%d, dev:%s\n", | |
b2d444d7 | 3373 | i, !test_bit(Faulty, &tmp->rdev->flags), |
1da177e4 LT |
3374 | bdevname(tmp->rdev->bdev,b)); |
3375 | } | |
3376 | } | |
3377 | ||
3378 | static int raid5_spare_active(mddev_t *mddev) | |
3379 | { | |
3380 | int i; | |
3381 | raid5_conf_t *conf = mddev->private; | |
3382 | struct disk_info *tmp; | |
3383 | ||
3384 | for (i = 0; i < conf->raid_disks; i++) { | |
3385 | tmp = conf->disks + i; | |
3386 | if (tmp->rdev | |
b2d444d7 N |
3387 | && !test_bit(Faulty, &tmp->rdev->flags) |
3388 | && !test_bit(In_sync, &tmp->rdev->flags)) { | |
1da177e4 LT |
3389 | mddev->degraded--; |
3390 | conf->failed_disks--; | |
3391 | conf->working_disks++; | |
b2d444d7 | 3392 | set_bit(In_sync, &tmp->rdev->flags); |
1da177e4 LT |
3393 | } |
3394 | } | |
3395 | print_raid5_conf(conf); | |
3396 | return 0; | |
3397 | } | |
3398 | ||
3399 | static int raid5_remove_disk(mddev_t *mddev, int number) | |
3400 | { | |
3401 | raid5_conf_t *conf = mddev->private; | |
3402 | int err = 0; | |
3403 | mdk_rdev_t *rdev; | |
3404 | struct disk_info *p = conf->disks + number; | |
3405 | ||
3406 | print_raid5_conf(conf); | |
3407 | rdev = p->rdev; | |
3408 | if (rdev) { | |
b2d444d7 | 3409 | if (test_bit(In_sync, &rdev->flags) || |
1da177e4 LT |
3410 | atomic_read(&rdev->nr_pending)) { |
3411 | err = -EBUSY; | |
3412 | goto abort; | |
3413 | } | |
3414 | p->rdev = NULL; | |
fbd568a3 | 3415 | synchronize_rcu(); |
1da177e4 LT |
3416 | if (atomic_read(&rdev->nr_pending)) { |
3417 | /* lost the race, try later */ | |
3418 | err = -EBUSY; | |
3419 | p->rdev = rdev; | |
3420 | } | |
3421 | } | |
3422 | abort: | |
3423 | ||
3424 | print_raid5_conf(conf); | |
3425 | return err; | |
3426 | } | |
3427 | ||
3428 | static int raid5_add_disk(mddev_t *mddev, mdk_rdev_t *rdev) | |
3429 | { | |
3430 | raid5_conf_t *conf = mddev->private; | |
3431 | int found = 0; | |
3432 | int disk; | |
3433 | struct disk_info *p; | |
3434 | ||
16a53ecc | 3435 | if (mddev->degraded > conf->max_degraded) |
1da177e4 LT |
3436 | /* no point adding a device */ |
3437 | return 0; | |
3438 | ||
3439 | /* | |
16a53ecc N |
3440 | * find the disk ... but prefer rdev->saved_raid_disk |
3441 | * if possible. | |
1da177e4 | 3442 | */ |
16a53ecc N |
3443 | if (rdev->saved_raid_disk >= 0 && |
3444 | conf->disks[rdev->saved_raid_disk].rdev == NULL) | |
3445 | disk = rdev->saved_raid_disk; | |
3446 | else | |
3447 | disk = 0; | |
3448 | for ( ; disk < conf->raid_disks; disk++) | |
1da177e4 | 3449 | if ((p=conf->disks + disk)->rdev == NULL) { |
b2d444d7 | 3450 | clear_bit(In_sync, &rdev->flags); |
1da177e4 LT |
3451 | rdev->raid_disk = disk; |
3452 | found = 1; | |
72626685 N |
3453 | if (rdev->saved_raid_disk != disk) |
3454 | conf->fullsync = 1; | |
d6065f7b | 3455 | rcu_assign_pointer(p->rdev, rdev); |
1da177e4 LT |
3456 | break; |
3457 | } | |
3458 | print_raid5_conf(conf); | |
3459 | return found; | |
3460 | } | |
3461 | ||
3462 | static int raid5_resize(mddev_t *mddev, sector_t sectors) | |
3463 | { | |
3464 | /* no resync is happening, and there is enough space | |
3465 | * on all devices, so we can resize. | |
3466 | * We need to make sure resync covers any new space. | |
3467 | * If the array is shrinking we should possibly wait until | |
3468 | * any io in the removed space completes, but it hardly seems | |
3469 | * worth it. | |
3470 | */ | |
16a53ecc N |
3471 | raid5_conf_t *conf = mddev_to_conf(mddev); |
3472 | ||
1da177e4 | 3473 | sectors &= ~((sector_t)mddev->chunk_size/512 - 1); |
16a53ecc | 3474 | mddev->array_size = (sectors * (mddev->raid_disks-conf->max_degraded))>>1; |
1da177e4 LT |
3475 | set_capacity(mddev->gendisk, mddev->array_size << 1); |
3476 | mddev->changed = 1; | |
3477 | if (sectors/2 > mddev->size && mddev->recovery_cp == MaxSector) { | |
3478 | mddev->recovery_cp = mddev->size << 1; | |
3479 | set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); | |
3480 | } | |
3481 | mddev->size = sectors /2; | |
4b5c7ae8 | 3482 | mddev->resync_max_sectors = sectors; |
1da177e4 LT |
3483 | return 0; |
3484 | } | |
3485 | ||
29269553 | 3486 | #ifdef CONFIG_MD_RAID5_RESHAPE |
63c70c4f | 3487 | static int raid5_check_reshape(mddev_t *mddev) |
29269553 N |
3488 | { |
3489 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
3490 | int err; | |
29269553 | 3491 | |
63c70c4f N |
3492 | if (mddev->delta_disks < 0 || |
3493 | mddev->new_level != mddev->level) | |
3494 | return -EINVAL; /* Cannot shrink array or change level yet */ | |
3495 | if (mddev->delta_disks == 0) | |
29269553 N |
3496 | return 0; /* nothing to do */ |
3497 | ||
3498 | /* Can only proceed if there are plenty of stripe_heads. | |
3499 | * We need a minimum of one full stripe,, and for sensible progress | |
3500 | * it is best to have about 4 times that. | |
3501 | * If we require 4 times, then the default 256 4K stripe_heads will | |
3502 | * allow for chunk sizes up to 256K, which is probably OK. | |
3503 | * If the chunk size is greater, user-space should request more | |
3504 | * stripe_heads first. | |
3505 | */ | |
63c70c4f N |
3506 | if ((mddev->chunk_size / STRIPE_SIZE) * 4 > conf->max_nr_stripes || |
3507 | (mddev->new_chunk / STRIPE_SIZE) * 4 > conf->max_nr_stripes) { | |
29269553 N |
3508 | printk(KERN_WARNING "raid5: reshape: not enough stripes. Needed %lu\n", |
3509 | (mddev->chunk_size / STRIPE_SIZE)*4); | |
3510 | return -ENOSPC; | |
3511 | } | |
3512 | ||
63c70c4f N |
3513 | err = resize_stripes(conf, conf->raid_disks + mddev->delta_disks); |
3514 | if (err) | |
3515 | return err; | |
3516 | ||
3517 | /* looks like we might be able to manage this */ | |
3518 | return 0; | |
3519 | } | |
3520 | ||
3521 | static int raid5_start_reshape(mddev_t *mddev) | |
3522 | { | |
3523 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
3524 | mdk_rdev_t *rdev; | |
3525 | struct list_head *rtmp; | |
3526 | int spares = 0; | |
3527 | int added_devices = 0; | |
3528 | ||
3529 | if (mddev->degraded || | |
3530 | test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) | |
3531 | return -EBUSY; | |
3532 | ||
29269553 N |
3533 | ITERATE_RDEV(mddev, rdev, rtmp) |
3534 | if (rdev->raid_disk < 0 && | |
3535 | !test_bit(Faulty, &rdev->flags)) | |
3536 | spares++; | |
63c70c4f N |
3537 | |
3538 | if (spares < mddev->delta_disks-1) | |
29269553 N |
3539 | /* Not enough devices even to make a degraded array |
3540 | * of that size | |
3541 | */ | |
3542 | return -EINVAL; | |
3543 | ||
f6705578 | 3544 | atomic_set(&conf->reshape_stripes, 0); |
29269553 N |
3545 | spin_lock_irq(&conf->device_lock); |
3546 | conf->previous_raid_disks = conf->raid_disks; | |
63c70c4f | 3547 | conf->raid_disks += mddev->delta_disks; |
29269553 | 3548 | conf->expand_progress = 0; |
b578d55f | 3549 | conf->expand_lo = 0; |
29269553 N |
3550 | spin_unlock_irq(&conf->device_lock); |
3551 | ||
3552 | /* Add some new drives, as many as will fit. | |
3553 | * We know there are enough to make the newly sized array work. | |
3554 | */ | |
3555 | ITERATE_RDEV(mddev, rdev, rtmp) | |
3556 | if (rdev->raid_disk < 0 && | |
3557 | !test_bit(Faulty, &rdev->flags)) { | |
3558 | if (raid5_add_disk(mddev, rdev)) { | |
3559 | char nm[20]; | |
3560 | set_bit(In_sync, &rdev->flags); | |
3561 | conf->working_disks++; | |
3562 | added_devices++; | |
5fd6c1dc | 3563 | rdev->recovery_offset = 0; |
29269553 N |
3564 | sprintf(nm, "rd%d", rdev->raid_disk); |
3565 | sysfs_create_link(&mddev->kobj, &rdev->kobj, nm); | |
3566 | } else | |
3567 | break; | |
3568 | } | |
3569 | ||
63c70c4f N |
3570 | mddev->degraded = (conf->raid_disks - conf->previous_raid_disks) - added_devices; |
3571 | mddev->raid_disks = conf->raid_disks; | |
f6705578 N |
3572 | mddev->reshape_position = 0; |
3573 | mddev->sb_dirty = 1; | |
3574 | ||
29269553 N |
3575 | clear_bit(MD_RECOVERY_SYNC, &mddev->recovery); |
3576 | clear_bit(MD_RECOVERY_CHECK, &mddev->recovery); | |
3577 | set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery); | |
3578 | set_bit(MD_RECOVERY_RUNNING, &mddev->recovery); | |
3579 | mddev->sync_thread = md_register_thread(md_do_sync, mddev, | |
3580 | "%s_reshape"); | |
3581 | if (!mddev->sync_thread) { | |
3582 | mddev->recovery = 0; | |
3583 | spin_lock_irq(&conf->device_lock); | |
3584 | mddev->raid_disks = conf->raid_disks = conf->previous_raid_disks; | |
3585 | conf->expand_progress = MaxSector; | |
3586 | spin_unlock_irq(&conf->device_lock); | |
3587 | return -EAGAIN; | |
3588 | } | |
3589 | md_wakeup_thread(mddev->sync_thread); | |
3590 | md_new_event(mddev); | |
3591 | return 0; | |
3592 | } | |
3593 | #endif | |
3594 | ||
3595 | static void end_reshape(raid5_conf_t *conf) | |
3596 | { | |
3597 | struct block_device *bdev; | |
3598 | ||
f6705578 N |
3599 | if (!test_bit(MD_RECOVERY_INTR, &conf->mddev->recovery)) { |
3600 | conf->mddev->array_size = conf->mddev->size * (conf->raid_disks-1); | |
3601 | set_capacity(conf->mddev->gendisk, conf->mddev->array_size << 1); | |
3602 | conf->mddev->changed = 1; | |
3603 | ||
3604 | bdev = bdget_disk(conf->mddev->gendisk, 0); | |
3605 | if (bdev) { | |
3606 | mutex_lock(&bdev->bd_inode->i_mutex); | |
3607 | i_size_write(bdev->bd_inode, conf->mddev->array_size << 10); | |
3608 | mutex_unlock(&bdev->bd_inode->i_mutex); | |
3609 | bdput(bdev); | |
3610 | } | |
3611 | spin_lock_irq(&conf->device_lock); | |
3612 | conf->expand_progress = MaxSector; | |
3613 | spin_unlock_irq(&conf->device_lock); | |
3614 | conf->mddev->reshape_position = MaxSector; | |
16a53ecc N |
3615 | |
3616 | /* read-ahead size must cover two whole stripes, which is | |
3617 | * 2 * (datadisks) * chunksize where 'n' is the number of raid devices | |
3618 | */ | |
3619 | { | |
3620 | int data_disks = conf->previous_raid_disks - conf->max_degraded; | |
3621 | int stripe = data_disks * | |
3622 | (conf->mddev->chunk_size / PAGE_SIZE); | |
3623 | if (conf->mddev->queue->backing_dev_info.ra_pages < 2 * stripe) | |
3624 | conf->mddev->queue->backing_dev_info.ra_pages = 2 * stripe; | |
3625 | } | |
29269553 | 3626 | } |
29269553 N |
3627 | } |
3628 | ||
72626685 N |
3629 | static void raid5_quiesce(mddev_t *mddev, int state) |
3630 | { | |
3631 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
3632 | ||
3633 | switch(state) { | |
e464eafd N |
3634 | case 2: /* resume for a suspend */ |
3635 | wake_up(&conf->wait_for_overlap); | |
3636 | break; | |
3637 | ||
72626685 N |
3638 | case 1: /* stop all writes */ |
3639 | spin_lock_irq(&conf->device_lock); | |
3640 | conf->quiesce = 1; | |
3641 | wait_event_lock_irq(conf->wait_for_stripe, | |
3642 | atomic_read(&conf->active_stripes) == 0, | |
3643 | conf->device_lock, /* nothing */); | |
3644 | spin_unlock_irq(&conf->device_lock); | |
3645 | break; | |
3646 | ||
3647 | case 0: /* re-enable writes */ | |
3648 | spin_lock_irq(&conf->device_lock); | |
3649 | conf->quiesce = 0; | |
3650 | wake_up(&conf->wait_for_stripe); | |
e464eafd | 3651 | wake_up(&conf->wait_for_overlap); |
72626685 N |
3652 | spin_unlock_irq(&conf->device_lock); |
3653 | break; | |
3654 | } | |
72626685 | 3655 | } |
b15c2e57 | 3656 | |
16a53ecc N |
3657 | static struct mdk_personality raid6_personality = |
3658 | { | |
3659 | .name = "raid6", | |
3660 | .level = 6, | |
3661 | .owner = THIS_MODULE, | |
3662 | .make_request = make_request, | |
3663 | .run = run, | |
3664 | .stop = stop, | |
3665 | .status = status, | |
3666 | .error_handler = error, | |
3667 | .hot_add_disk = raid5_add_disk, | |
3668 | .hot_remove_disk= raid5_remove_disk, | |
3669 | .spare_active = raid5_spare_active, | |
3670 | .sync_request = sync_request, | |
3671 | .resize = raid5_resize, | |
3672 | .quiesce = raid5_quiesce, | |
3673 | }; | |
2604b703 | 3674 | static struct mdk_personality raid5_personality = |
1da177e4 LT |
3675 | { |
3676 | .name = "raid5", | |
2604b703 | 3677 | .level = 5, |
1da177e4 LT |
3678 | .owner = THIS_MODULE, |
3679 | .make_request = make_request, | |
3680 | .run = run, | |
3681 | .stop = stop, | |
3682 | .status = status, | |
3683 | .error_handler = error, | |
3684 | .hot_add_disk = raid5_add_disk, | |
3685 | .hot_remove_disk= raid5_remove_disk, | |
3686 | .spare_active = raid5_spare_active, | |
3687 | .sync_request = sync_request, | |
3688 | .resize = raid5_resize, | |
29269553 | 3689 | #ifdef CONFIG_MD_RAID5_RESHAPE |
63c70c4f N |
3690 | .check_reshape = raid5_check_reshape, |
3691 | .start_reshape = raid5_start_reshape, | |
29269553 | 3692 | #endif |
72626685 | 3693 | .quiesce = raid5_quiesce, |
1da177e4 LT |
3694 | }; |
3695 | ||
2604b703 | 3696 | static struct mdk_personality raid4_personality = |
1da177e4 | 3697 | { |
2604b703 N |
3698 | .name = "raid4", |
3699 | .level = 4, | |
3700 | .owner = THIS_MODULE, | |
3701 | .make_request = make_request, | |
3702 | .run = run, | |
3703 | .stop = stop, | |
3704 | .status = status, | |
3705 | .error_handler = error, | |
3706 | .hot_add_disk = raid5_add_disk, | |
3707 | .hot_remove_disk= raid5_remove_disk, | |
3708 | .spare_active = raid5_spare_active, | |
3709 | .sync_request = sync_request, | |
3710 | .resize = raid5_resize, | |
3711 | .quiesce = raid5_quiesce, | |
3712 | }; | |
3713 | ||
3714 | static int __init raid5_init(void) | |
3715 | { | |
16a53ecc N |
3716 | int e; |
3717 | ||
3718 | e = raid6_select_algo(); | |
3719 | if ( e ) | |
3720 | return e; | |
3721 | register_md_personality(&raid6_personality); | |
2604b703 N |
3722 | register_md_personality(&raid5_personality); |
3723 | register_md_personality(&raid4_personality); | |
3724 | return 0; | |
1da177e4 LT |
3725 | } |
3726 | ||
2604b703 | 3727 | static void raid5_exit(void) |
1da177e4 | 3728 | { |
16a53ecc | 3729 | unregister_md_personality(&raid6_personality); |
2604b703 N |
3730 | unregister_md_personality(&raid5_personality); |
3731 | unregister_md_personality(&raid4_personality); | |
1da177e4 LT |
3732 | } |
3733 | ||
3734 | module_init(raid5_init); | |
3735 | module_exit(raid5_exit); | |
3736 | MODULE_LICENSE("GPL"); | |
3737 | MODULE_ALIAS("md-personality-4"); /* RAID5 */ | |
d9d166c2 N |
3738 | MODULE_ALIAS("md-raid5"); |
3739 | MODULE_ALIAS("md-raid4"); | |
2604b703 N |
3740 | MODULE_ALIAS("md-level-5"); |
3741 | MODULE_ALIAS("md-level-4"); | |
16a53ecc N |
3742 | MODULE_ALIAS("md-personality-8"); /* RAID6 */ |
3743 | MODULE_ALIAS("md-raid6"); | |
3744 | MODULE_ALIAS("md-level-6"); | |
3745 | ||
3746 | /* This used to be two separate modules, they were: */ | |
3747 | MODULE_ALIAS("raid5"); | |
3748 | MODULE_ALIAS("raid6"); |