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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * raid5.c : Multiple Devices driver for Linux | |
3 | * Copyright (C) 1996, 1997 Ingo Molnar, Miguel de Icaza, Gadi Oxman | |
4 | * Copyright (C) 1999, 2000 Ingo Molnar | |
16a53ecc | 5 | * Copyright (C) 2002, 2003 H. Peter Anvin |
1da177e4 | 6 | * |
16a53ecc N |
7 | * RAID-4/5/6 management functions. |
8 | * Thanks to Penguin Computing for making the RAID-6 development possible | |
9 | * by donating a test server! | |
1da177e4 LT |
10 | * |
11 | * This program is free software; you can redistribute it and/or modify | |
12 | * it under the terms of the GNU General Public License as published by | |
13 | * the Free Software Foundation; either version 2, or (at your option) | |
14 | * any later version. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License | |
17 | * (for example /usr/src/linux/COPYING); if not, write to the Free | |
18 | * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | |
19 | */ | |
20 | ||
ae3c20cc N |
21 | /* |
22 | * BITMAP UNPLUGGING: | |
23 | * | |
24 | * The sequencing for updating the bitmap reliably is a little | |
25 | * subtle (and I got it wrong the first time) so it deserves some | |
26 | * explanation. | |
27 | * | |
28 | * We group bitmap updates into batches. Each batch has a number. | |
29 | * We may write out several batches at once, but that isn't very important. | |
30 | * conf->bm_write is the number of the last batch successfully written. | |
31 | * conf->bm_flush is the number of the last batch that was closed to | |
32 | * new additions. | |
33 | * When we discover that we will need to write to any block in a stripe | |
34 | * (in add_stripe_bio) we update the in-memory bitmap and record in sh->bm_seq | |
35 | * the number of the batch it will be in. This is bm_flush+1. | |
36 | * When we are ready to do a write, if that batch hasn't been written yet, | |
37 | * we plug the array and queue the stripe for later. | |
38 | * When an unplug happens, we increment bm_flush, thus closing the current | |
39 | * batch. | |
40 | * When we notice that bm_flush > bm_write, we write out all pending updates | |
41 | * to the bitmap, and advance bm_write to where bm_flush was. | |
42 | * This may occasionally write a bit out twice, but is sure never to | |
43 | * miss any bits. | |
44 | */ | |
1da177e4 | 45 | |
bff61975 | 46 | #include <linux/blkdev.h> |
f6705578 | 47 | #include <linux/kthread.h> |
f701d589 | 48 | #include <linux/raid/pq.h> |
91c00924 | 49 | #include <linux/async_tx.h> |
bff61975 | 50 | #include <linux/seq_file.h> |
43b2e5d8 | 51 | #include "md.h" |
bff61975 | 52 | #include "raid5.h" |
ef740c37 | 53 | #include "bitmap.h" |
72626685 | 54 | |
1da177e4 LT |
55 | /* |
56 | * Stripe cache | |
57 | */ | |
58 | ||
59 | #define NR_STRIPES 256 | |
60 | #define STRIPE_SIZE PAGE_SIZE | |
61 | #define STRIPE_SHIFT (PAGE_SHIFT - 9) | |
62 | #define STRIPE_SECTORS (STRIPE_SIZE>>9) | |
63 | #define IO_THRESHOLD 1 | |
8b3e6cdc | 64 | #define BYPASS_THRESHOLD 1 |
fccddba0 | 65 | #define NR_HASH (PAGE_SIZE / sizeof(struct hlist_head)) |
1da177e4 LT |
66 | #define HASH_MASK (NR_HASH - 1) |
67 | ||
fccddba0 | 68 | #define stripe_hash(conf, sect) (&((conf)->stripe_hashtbl[((sect) >> STRIPE_SHIFT) & HASH_MASK])) |
1da177e4 LT |
69 | |
70 | /* bio's attached to a stripe+device for I/O are linked together in bi_sector | |
71 | * order without overlap. There may be several bio's per stripe+device, and | |
72 | * a bio could span several devices. | |
73 | * When walking this list for a particular stripe+device, we must never proceed | |
74 | * beyond a bio that extends past this device, as the next bio might no longer | |
75 | * be valid. | |
76 | * This macro is used to determine the 'next' bio in the list, given the sector | |
77 | * of the current stripe+device | |
78 | */ | |
79 | #define r5_next_bio(bio, sect) ( ( (bio)->bi_sector + ((bio)->bi_size>>9) < sect + STRIPE_SECTORS) ? (bio)->bi_next : NULL) | |
80 | /* | |
81 | * The following can be used to debug the driver | |
82 | */ | |
1da177e4 LT |
83 | #define RAID5_PARANOIA 1 |
84 | #if RAID5_PARANOIA && defined(CONFIG_SMP) | |
85 | # define CHECK_DEVLOCK() assert_spin_locked(&conf->device_lock) | |
86 | #else | |
87 | # define CHECK_DEVLOCK() | |
88 | #endif | |
89 | ||
45b4233c | 90 | #ifdef DEBUG |
1da177e4 LT |
91 | #define inline |
92 | #define __inline__ | |
93 | #endif | |
94 | ||
6be9d494 BS |
95 | #define printk_rl(args...) ((void) (printk_ratelimit() && printk(args))) |
96 | ||
960e739d | 97 | /* |
5b99c2ff JA |
98 | * We maintain a biased count of active stripes in the bottom 16 bits of |
99 | * bi_phys_segments, and a count of processed stripes in the upper 16 bits | |
960e739d JA |
100 | */ |
101 | static inline int raid5_bi_phys_segments(struct bio *bio) | |
102 | { | |
5b99c2ff | 103 | return bio->bi_phys_segments & 0xffff; |
960e739d JA |
104 | } |
105 | ||
106 | static inline int raid5_bi_hw_segments(struct bio *bio) | |
107 | { | |
5b99c2ff | 108 | return (bio->bi_phys_segments >> 16) & 0xffff; |
960e739d JA |
109 | } |
110 | ||
111 | static inline int raid5_dec_bi_phys_segments(struct bio *bio) | |
112 | { | |
113 | --bio->bi_phys_segments; | |
114 | return raid5_bi_phys_segments(bio); | |
115 | } | |
116 | ||
117 | static inline int raid5_dec_bi_hw_segments(struct bio *bio) | |
118 | { | |
119 | unsigned short val = raid5_bi_hw_segments(bio); | |
120 | ||
121 | --val; | |
5b99c2ff | 122 | bio->bi_phys_segments = (val << 16) | raid5_bi_phys_segments(bio); |
960e739d JA |
123 | return val; |
124 | } | |
125 | ||
126 | static inline void raid5_set_bi_hw_segments(struct bio *bio, unsigned int cnt) | |
127 | { | |
5b99c2ff | 128 | bio->bi_phys_segments = raid5_bi_phys_segments(bio) || (cnt << 16); |
960e739d JA |
129 | } |
130 | ||
d0dabf7e N |
131 | /* Find first data disk in a raid6 stripe */ |
132 | static inline int raid6_d0(struct stripe_head *sh) | |
133 | { | |
67cc2b81 N |
134 | if (sh->ddf_layout) |
135 | /* ddf always start from first device */ | |
136 | return 0; | |
137 | /* md starts just after Q block */ | |
d0dabf7e N |
138 | if (sh->qd_idx == sh->disks - 1) |
139 | return 0; | |
140 | else | |
141 | return sh->qd_idx + 1; | |
142 | } | |
16a53ecc N |
143 | static inline int raid6_next_disk(int disk, int raid_disks) |
144 | { | |
145 | disk++; | |
146 | return (disk < raid_disks) ? disk : 0; | |
147 | } | |
a4456856 | 148 | |
d0dabf7e N |
149 | /* When walking through the disks in a raid5, starting at raid6_d0, |
150 | * We need to map each disk to a 'slot', where the data disks are slot | |
151 | * 0 .. raid_disks-3, the parity disk is raid_disks-2 and the Q disk | |
152 | * is raid_disks-1. This help does that mapping. | |
153 | */ | |
67cc2b81 N |
154 | static int raid6_idx_to_slot(int idx, struct stripe_head *sh, |
155 | int *count, int syndrome_disks) | |
d0dabf7e N |
156 | { |
157 | int slot; | |
67cc2b81 | 158 | |
d0dabf7e | 159 | if (idx == sh->pd_idx) |
67cc2b81 | 160 | return syndrome_disks; |
d0dabf7e | 161 | if (idx == sh->qd_idx) |
67cc2b81 | 162 | return syndrome_disks + 1; |
d0dabf7e N |
163 | slot = (*count)++; |
164 | return slot; | |
165 | } | |
166 | ||
a4456856 DW |
167 | static void return_io(struct bio *return_bi) |
168 | { | |
169 | struct bio *bi = return_bi; | |
170 | while (bi) { | |
a4456856 DW |
171 | |
172 | return_bi = bi->bi_next; | |
173 | bi->bi_next = NULL; | |
174 | bi->bi_size = 0; | |
0e13fe23 | 175 | bio_endio(bi, 0); |
a4456856 DW |
176 | bi = return_bi; |
177 | } | |
178 | } | |
179 | ||
1da177e4 LT |
180 | static void print_raid5_conf (raid5_conf_t *conf); |
181 | ||
600aa109 DW |
182 | static int stripe_operations_active(struct stripe_head *sh) |
183 | { | |
184 | return sh->check_state || sh->reconstruct_state || | |
185 | test_bit(STRIPE_BIOFILL_RUN, &sh->state) || | |
186 | test_bit(STRIPE_COMPUTE_RUN, &sh->state); | |
187 | } | |
188 | ||
858119e1 | 189 | static void __release_stripe(raid5_conf_t *conf, struct stripe_head *sh) |
1da177e4 LT |
190 | { |
191 | if (atomic_dec_and_test(&sh->count)) { | |
78bafebd ES |
192 | BUG_ON(!list_empty(&sh->lru)); |
193 | BUG_ON(atomic_read(&conf->active_stripes)==0); | |
1da177e4 | 194 | if (test_bit(STRIPE_HANDLE, &sh->state)) { |
7c785b7a | 195 | if (test_bit(STRIPE_DELAYED, &sh->state)) { |
1da177e4 | 196 | list_add_tail(&sh->lru, &conf->delayed_list); |
7c785b7a N |
197 | blk_plug_device(conf->mddev->queue); |
198 | } else if (test_bit(STRIPE_BIT_DELAY, &sh->state) && | |
ae3c20cc | 199 | sh->bm_seq - conf->seq_write > 0) { |
72626685 | 200 | list_add_tail(&sh->lru, &conf->bitmap_list); |
7c785b7a N |
201 | blk_plug_device(conf->mddev->queue); |
202 | } else { | |
72626685 | 203 | clear_bit(STRIPE_BIT_DELAY, &sh->state); |
1da177e4 | 204 | list_add_tail(&sh->lru, &conf->handle_list); |
72626685 | 205 | } |
1da177e4 LT |
206 | md_wakeup_thread(conf->mddev->thread); |
207 | } else { | |
600aa109 | 208 | BUG_ON(stripe_operations_active(sh)); |
1da177e4 LT |
209 | if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { |
210 | atomic_dec(&conf->preread_active_stripes); | |
211 | if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD) | |
212 | md_wakeup_thread(conf->mddev->thread); | |
213 | } | |
1da177e4 | 214 | atomic_dec(&conf->active_stripes); |
ccfcc3c1 N |
215 | if (!test_bit(STRIPE_EXPANDING, &sh->state)) { |
216 | list_add_tail(&sh->lru, &conf->inactive_list); | |
1da177e4 | 217 | wake_up(&conf->wait_for_stripe); |
46031f9a RBJ |
218 | if (conf->retry_read_aligned) |
219 | md_wakeup_thread(conf->mddev->thread); | |
ccfcc3c1 | 220 | } |
1da177e4 LT |
221 | } |
222 | } | |
223 | } | |
d0dabf7e | 224 | |
1da177e4 LT |
225 | static void release_stripe(struct stripe_head *sh) |
226 | { | |
227 | raid5_conf_t *conf = sh->raid_conf; | |
228 | unsigned long flags; | |
16a53ecc | 229 | |
1da177e4 LT |
230 | spin_lock_irqsave(&conf->device_lock, flags); |
231 | __release_stripe(conf, sh); | |
232 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
233 | } | |
234 | ||
fccddba0 | 235 | static inline void remove_hash(struct stripe_head *sh) |
1da177e4 | 236 | { |
45b4233c DW |
237 | pr_debug("remove_hash(), stripe %llu\n", |
238 | (unsigned long long)sh->sector); | |
1da177e4 | 239 | |
fccddba0 | 240 | hlist_del_init(&sh->hash); |
1da177e4 LT |
241 | } |
242 | ||
16a53ecc | 243 | static inline void insert_hash(raid5_conf_t *conf, struct stripe_head *sh) |
1da177e4 | 244 | { |
fccddba0 | 245 | struct hlist_head *hp = stripe_hash(conf, sh->sector); |
1da177e4 | 246 | |
45b4233c DW |
247 | pr_debug("insert_hash(), stripe %llu\n", |
248 | (unsigned long long)sh->sector); | |
1da177e4 LT |
249 | |
250 | CHECK_DEVLOCK(); | |
fccddba0 | 251 | hlist_add_head(&sh->hash, hp); |
1da177e4 LT |
252 | } |
253 | ||
254 | ||
255 | /* find an idle stripe, make sure it is unhashed, and return it. */ | |
256 | static struct stripe_head *get_free_stripe(raid5_conf_t *conf) | |
257 | { | |
258 | struct stripe_head *sh = NULL; | |
259 | struct list_head *first; | |
260 | ||
261 | CHECK_DEVLOCK(); | |
262 | if (list_empty(&conf->inactive_list)) | |
263 | goto out; | |
264 | first = conf->inactive_list.next; | |
265 | sh = list_entry(first, struct stripe_head, lru); | |
266 | list_del_init(first); | |
267 | remove_hash(sh); | |
268 | atomic_inc(&conf->active_stripes); | |
269 | out: | |
270 | return sh; | |
271 | } | |
272 | ||
273 | static void shrink_buffers(struct stripe_head *sh, int num) | |
274 | { | |
275 | struct page *p; | |
276 | int i; | |
277 | ||
278 | for (i=0; i<num ; i++) { | |
279 | p = sh->dev[i].page; | |
280 | if (!p) | |
281 | continue; | |
282 | sh->dev[i].page = NULL; | |
2d1f3b5d | 283 | put_page(p); |
1da177e4 LT |
284 | } |
285 | } | |
286 | ||
287 | static int grow_buffers(struct stripe_head *sh, int num) | |
288 | { | |
289 | int i; | |
290 | ||
291 | for (i=0; i<num; i++) { | |
292 | struct page *page; | |
293 | ||
294 | if (!(page = alloc_page(GFP_KERNEL))) { | |
295 | return 1; | |
296 | } | |
297 | sh->dev[i].page = page; | |
298 | } | |
299 | return 0; | |
300 | } | |
301 | ||
784052ec | 302 | static void raid5_build_block(struct stripe_head *sh, int i, int previous); |
911d4ee8 N |
303 | static void stripe_set_idx(sector_t stripe, raid5_conf_t *conf, int previous, |
304 | struct stripe_head *sh); | |
1da177e4 | 305 | |
b5663ba4 | 306 | static void init_stripe(struct stripe_head *sh, sector_t sector, int previous) |
1da177e4 LT |
307 | { |
308 | raid5_conf_t *conf = sh->raid_conf; | |
7ecaa1e6 | 309 | int i; |
1da177e4 | 310 | |
78bafebd ES |
311 | BUG_ON(atomic_read(&sh->count) != 0); |
312 | BUG_ON(test_bit(STRIPE_HANDLE, &sh->state)); | |
600aa109 | 313 | BUG_ON(stripe_operations_active(sh)); |
d84e0f10 | 314 | |
1da177e4 | 315 | CHECK_DEVLOCK(); |
45b4233c | 316 | pr_debug("init_stripe called, stripe %llu\n", |
1da177e4 LT |
317 | (unsigned long long)sh->sector); |
318 | ||
319 | remove_hash(sh); | |
16a53ecc | 320 | |
86b42c71 | 321 | sh->generation = conf->generation - previous; |
b5663ba4 | 322 | sh->disks = previous ? conf->previous_raid_disks : conf->raid_disks; |
1da177e4 | 323 | sh->sector = sector; |
911d4ee8 | 324 | stripe_set_idx(sector, conf, previous, sh); |
1da177e4 LT |
325 | sh->state = 0; |
326 | ||
7ecaa1e6 N |
327 | |
328 | for (i = sh->disks; i--; ) { | |
1da177e4 LT |
329 | struct r5dev *dev = &sh->dev[i]; |
330 | ||
d84e0f10 | 331 | if (dev->toread || dev->read || dev->towrite || dev->written || |
1da177e4 | 332 | test_bit(R5_LOCKED, &dev->flags)) { |
d84e0f10 | 333 | printk(KERN_ERR "sector=%llx i=%d %p %p %p %p %d\n", |
1da177e4 | 334 | (unsigned long long)sh->sector, i, dev->toread, |
d84e0f10 | 335 | dev->read, dev->towrite, dev->written, |
1da177e4 LT |
336 | test_bit(R5_LOCKED, &dev->flags)); |
337 | BUG(); | |
338 | } | |
339 | dev->flags = 0; | |
784052ec | 340 | raid5_build_block(sh, i, previous); |
1da177e4 LT |
341 | } |
342 | insert_hash(conf, sh); | |
343 | } | |
344 | ||
86b42c71 N |
345 | static struct stripe_head *__find_stripe(raid5_conf_t *conf, sector_t sector, |
346 | short generation) | |
1da177e4 LT |
347 | { |
348 | struct stripe_head *sh; | |
fccddba0 | 349 | struct hlist_node *hn; |
1da177e4 LT |
350 | |
351 | CHECK_DEVLOCK(); | |
45b4233c | 352 | pr_debug("__find_stripe, sector %llu\n", (unsigned long long)sector); |
fccddba0 | 353 | hlist_for_each_entry(sh, hn, stripe_hash(conf, sector), hash) |
86b42c71 | 354 | if (sh->sector == sector && sh->generation == generation) |
1da177e4 | 355 | return sh; |
45b4233c | 356 | pr_debug("__stripe %llu not in cache\n", (unsigned long long)sector); |
1da177e4 LT |
357 | return NULL; |
358 | } | |
359 | ||
360 | static void unplug_slaves(mddev_t *mddev); | |
165125e1 | 361 | static void raid5_unplug_device(struct request_queue *q); |
1da177e4 | 362 | |
b5663ba4 N |
363 | static struct stripe_head * |
364 | get_active_stripe(raid5_conf_t *conf, sector_t sector, | |
365 | int previous, int noblock) | |
1da177e4 LT |
366 | { |
367 | struct stripe_head *sh; | |
368 | ||
45b4233c | 369 | pr_debug("get_stripe, sector %llu\n", (unsigned long long)sector); |
1da177e4 LT |
370 | |
371 | spin_lock_irq(&conf->device_lock); | |
372 | ||
373 | do { | |
72626685 N |
374 | wait_event_lock_irq(conf->wait_for_stripe, |
375 | conf->quiesce == 0, | |
376 | conf->device_lock, /* nothing */); | |
86b42c71 | 377 | sh = __find_stripe(conf, sector, conf->generation - previous); |
1da177e4 LT |
378 | if (!sh) { |
379 | if (!conf->inactive_blocked) | |
380 | sh = get_free_stripe(conf); | |
381 | if (noblock && sh == NULL) | |
382 | break; | |
383 | if (!sh) { | |
384 | conf->inactive_blocked = 1; | |
385 | wait_event_lock_irq(conf->wait_for_stripe, | |
386 | !list_empty(&conf->inactive_list) && | |
5036805b N |
387 | (atomic_read(&conf->active_stripes) |
388 | < (conf->max_nr_stripes *3/4) | |
1da177e4 LT |
389 | || !conf->inactive_blocked), |
390 | conf->device_lock, | |
f4370781 | 391 | raid5_unplug_device(conf->mddev->queue) |
1da177e4 LT |
392 | ); |
393 | conf->inactive_blocked = 0; | |
394 | } else | |
b5663ba4 | 395 | init_stripe(sh, sector, previous); |
1da177e4 LT |
396 | } else { |
397 | if (atomic_read(&sh->count)) { | |
78bafebd | 398 | BUG_ON(!list_empty(&sh->lru)); |
1da177e4 LT |
399 | } else { |
400 | if (!test_bit(STRIPE_HANDLE, &sh->state)) | |
401 | atomic_inc(&conf->active_stripes); | |
ff4e8d9a N |
402 | if (list_empty(&sh->lru) && |
403 | !test_bit(STRIPE_EXPANDING, &sh->state)) | |
16a53ecc N |
404 | BUG(); |
405 | list_del_init(&sh->lru); | |
1da177e4 LT |
406 | } |
407 | } | |
408 | } while (sh == NULL); | |
409 | ||
410 | if (sh) | |
411 | atomic_inc(&sh->count); | |
412 | ||
413 | spin_unlock_irq(&conf->device_lock); | |
414 | return sh; | |
415 | } | |
416 | ||
6712ecf8 N |
417 | static void |
418 | raid5_end_read_request(struct bio *bi, int error); | |
419 | static void | |
420 | raid5_end_write_request(struct bio *bi, int error); | |
91c00924 | 421 | |
c4e5ac0a | 422 | static void ops_run_io(struct stripe_head *sh, struct stripe_head_state *s) |
91c00924 DW |
423 | { |
424 | raid5_conf_t *conf = sh->raid_conf; | |
425 | int i, disks = sh->disks; | |
426 | ||
427 | might_sleep(); | |
428 | ||
429 | for (i = disks; i--; ) { | |
430 | int rw; | |
431 | struct bio *bi; | |
432 | mdk_rdev_t *rdev; | |
433 | if (test_and_clear_bit(R5_Wantwrite, &sh->dev[i].flags)) | |
434 | rw = WRITE; | |
435 | else if (test_and_clear_bit(R5_Wantread, &sh->dev[i].flags)) | |
436 | rw = READ; | |
437 | else | |
438 | continue; | |
439 | ||
440 | bi = &sh->dev[i].req; | |
441 | ||
442 | bi->bi_rw = rw; | |
443 | if (rw == WRITE) | |
444 | bi->bi_end_io = raid5_end_write_request; | |
445 | else | |
446 | bi->bi_end_io = raid5_end_read_request; | |
447 | ||
448 | rcu_read_lock(); | |
449 | rdev = rcu_dereference(conf->disks[i].rdev); | |
450 | if (rdev && test_bit(Faulty, &rdev->flags)) | |
451 | rdev = NULL; | |
452 | if (rdev) | |
453 | atomic_inc(&rdev->nr_pending); | |
454 | rcu_read_unlock(); | |
455 | ||
456 | if (rdev) { | |
c4e5ac0a | 457 | if (s->syncing || s->expanding || s->expanded) |
91c00924 DW |
458 | md_sync_acct(rdev->bdev, STRIPE_SECTORS); |
459 | ||
2b7497f0 DW |
460 | set_bit(STRIPE_IO_STARTED, &sh->state); |
461 | ||
91c00924 DW |
462 | bi->bi_bdev = rdev->bdev; |
463 | pr_debug("%s: for %llu schedule op %ld on disc %d\n", | |
e46b272b | 464 | __func__, (unsigned long long)sh->sector, |
91c00924 DW |
465 | bi->bi_rw, i); |
466 | atomic_inc(&sh->count); | |
467 | bi->bi_sector = sh->sector + rdev->data_offset; | |
468 | bi->bi_flags = 1 << BIO_UPTODATE; | |
469 | bi->bi_vcnt = 1; | |
470 | bi->bi_max_vecs = 1; | |
471 | bi->bi_idx = 0; | |
472 | bi->bi_io_vec = &sh->dev[i].vec; | |
473 | bi->bi_io_vec[0].bv_len = STRIPE_SIZE; | |
474 | bi->bi_io_vec[0].bv_offset = 0; | |
475 | bi->bi_size = STRIPE_SIZE; | |
476 | bi->bi_next = NULL; | |
477 | if (rw == WRITE && | |
478 | test_bit(R5_ReWrite, &sh->dev[i].flags)) | |
479 | atomic_add(STRIPE_SECTORS, | |
480 | &rdev->corrected_errors); | |
481 | generic_make_request(bi); | |
482 | } else { | |
483 | if (rw == WRITE) | |
484 | set_bit(STRIPE_DEGRADED, &sh->state); | |
485 | pr_debug("skip op %ld on disc %d for sector %llu\n", | |
486 | bi->bi_rw, i, (unsigned long long)sh->sector); | |
487 | clear_bit(R5_LOCKED, &sh->dev[i].flags); | |
488 | set_bit(STRIPE_HANDLE, &sh->state); | |
489 | } | |
490 | } | |
491 | } | |
492 | ||
493 | static struct dma_async_tx_descriptor * | |
494 | async_copy_data(int frombio, struct bio *bio, struct page *page, | |
495 | sector_t sector, struct dma_async_tx_descriptor *tx) | |
496 | { | |
497 | struct bio_vec *bvl; | |
498 | struct page *bio_page; | |
499 | int i; | |
500 | int page_offset; | |
501 | ||
502 | if (bio->bi_sector >= sector) | |
503 | page_offset = (signed)(bio->bi_sector - sector) * 512; | |
504 | else | |
505 | page_offset = (signed)(sector - bio->bi_sector) * -512; | |
506 | bio_for_each_segment(bvl, bio, i) { | |
507 | int len = bio_iovec_idx(bio, i)->bv_len; | |
508 | int clen; | |
509 | int b_offset = 0; | |
510 | ||
511 | if (page_offset < 0) { | |
512 | b_offset = -page_offset; | |
513 | page_offset += b_offset; | |
514 | len -= b_offset; | |
515 | } | |
516 | ||
517 | if (len > 0 && page_offset + len > STRIPE_SIZE) | |
518 | clen = STRIPE_SIZE - page_offset; | |
519 | else | |
520 | clen = len; | |
521 | ||
522 | if (clen > 0) { | |
523 | b_offset += bio_iovec_idx(bio, i)->bv_offset; | |
524 | bio_page = bio_iovec_idx(bio, i)->bv_page; | |
525 | if (frombio) | |
526 | tx = async_memcpy(page, bio_page, page_offset, | |
527 | b_offset, clen, | |
eb0645a8 | 528 | ASYNC_TX_DEP_ACK, |
91c00924 DW |
529 | tx, NULL, NULL); |
530 | else | |
531 | tx = async_memcpy(bio_page, page, b_offset, | |
532 | page_offset, clen, | |
eb0645a8 | 533 | ASYNC_TX_DEP_ACK, |
91c00924 DW |
534 | tx, NULL, NULL); |
535 | } | |
536 | if (clen < len) /* hit end of page */ | |
537 | break; | |
538 | page_offset += len; | |
539 | } | |
540 | ||
541 | return tx; | |
542 | } | |
543 | ||
544 | static void ops_complete_biofill(void *stripe_head_ref) | |
545 | { | |
546 | struct stripe_head *sh = stripe_head_ref; | |
547 | struct bio *return_bi = NULL; | |
548 | raid5_conf_t *conf = sh->raid_conf; | |
e4d84909 | 549 | int i; |
91c00924 | 550 | |
e46b272b | 551 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
552 | (unsigned long long)sh->sector); |
553 | ||
554 | /* clear completed biofills */ | |
83de75cc | 555 | spin_lock_irq(&conf->device_lock); |
91c00924 DW |
556 | for (i = sh->disks; i--; ) { |
557 | struct r5dev *dev = &sh->dev[i]; | |
91c00924 DW |
558 | |
559 | /* acknowledge completion of a biofill operation */ | |
e4d84909 DW |
560 | /* and check if we need to reply to a read request, |
561 | * new R5_Wantfill requests are held off until | |
83de75cc | 562 | * !STRIPE_BIOFILL_RUN |
e4d84909 DW |
563 | */ |
564 | if (test_and_clear_bit(R5_Wantfill, &dev->flags)) { | |
91c00924 | 565 | struct bio *rbi, *rbi2; |
91c00924 | 566 | |
91c00924 DW |
567 | BUG_ON(!dev->read); |
568 | rbi = dev->read; | |
569 | dev->read = NULL; | |
570 | while (rbi && rbi->bi_sector < | |
571 | dev->sector + STRIPE_SECTORS) { | |
572 | rbi2 = r5_next_bio(rbi, dev->sector); | |
960e739d | 573 | if (!raid5_dec_bi_phys_segments(rbi)) { |
91c00924 DW |
574 | rbi->bi_next = return_bi; |
575 | return_bi = rbi; | |
576 | } | |
91c00924 DW |
577 | rbi = rbi2; |
578 | } | |
579 | } | |
580 | } | |
83de75cc DW |
581 | spin_unlock_irq(&conf->device_lock); |
582 | clear_bit(STRIPE_BIOFILL_RUN, &sh->state); | |
91c00924 DW |
583 | |
584 | return_io(return_bi); | |
585 | ||
e4d84909 | 586 | set_bit(STRIPE_HANDLE, &sh->state); |
91c00924 DW |
587 | release_stripe(sh); |
588 | } | |
589 | ||
590 | static void ops_run_biofill(struct stripe_head *sh) | |
591 | { | |
592 | struct dma_async_tx_descriptor *tx = NULL; | |
593 | raid5_conf_t *conf = sh->raid_conf; | |
594 | int i; | |
595 | ||
e46b272b | 596 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
597 | (unsigned long long)sh->sector); |
598 | ||
599 | for (i = sh->disks; i--; ) { | |
600 | struct r5dev *dev = &sh->dev[i]; | |
601 | if (test_bit(R5_Wantfill, &dev->flags)) { | |
602 | struct bio *rbi; | |
603 | spin_lock_irq(&conf->device_lock); | |
604 | dev->read = rbi = dev->toread; | |
605 | dev->toread = NULL; | |
606 | spin_unlock_irq(&conf->device_lock); | |
607 | while (rbi && rbi->bi_sector < | |
608 | dev->sector + STRIPE_SECTORS) { | |
609 | tx = async_copy_data(0, rbi, dev->page, | |
610 | dev->sector, tx); | |
611 | rbi = r5_next_bio(rbi, dev->sector); | |
612 | } | |
613 | } | |
614 | } | |
615 | ||
616 | atomic_inc(&sh->count); | |
617 | async_trigger_callback(ASYNC_TX_DEP_ACK | ASYNC_TX_ACK, tx, | |
618 | ops_complete_biofill, sh); | |
619 | } | |
620 | ||
621 | static void ops_complete_compute5(void *stripe_head_ref) | |
622 | { | |
623 | struct stripe_head *sh = stripe_head_ref; | |
624 | int target = sh->ops.target; | |
625 | struct r5dev *tgt = &sh->dev[target]; | |
626 | ||
e46b272b | 627 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
628 | (unsigned long long)sh->sector); |
629 | ||
630 | set_bit(R5_UPTODATE, &tgt->flags); | |
631 | BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags)); | |
632 | clear_bit(R5_Wantcompute, &tgt->flags); | |
ecc65c9b DW |
633 | clear_bit(STRIPE_COMPUTE_RUN, &sh->state); |
634 | if (sh->check_state == check_state_compute_run) | |
635 | sh->check_state = check_state_compute_result; | |
91c00924 DW |
636 | set_bit(STRIPE_HANDLE, &sh->state); |
637 | release_stripe(sh); | |
638 | } | |
639 | ||
7b3a871e | 640 | static struct dma_async_tx_descriptor *ops_run_compute5(struct stripe_head *sh) |
91c00924 DW |
641 | { |
642 | /* kernel stack size limits the total number of disks */ | |
643 | int disks = sh->disks; | |
644 | struct page *xor_srcs[disks]; | |
645 | int target = sh->ops.target; | |
646 | struct r5dev *tgt = &sh->dev[target]; | |
647 | struct page *xor_dest = tgt->page; | |
648 | int count = 0; | |
649 | struct dma_async_tx_descriptor *tx; | |
650 | int i; | |
651 | ||
652 | pr_debug("%s: stripe %llu block: %d\n", | |
e46b272b | 653 | __func__, (unsigned long long)sh->sector, target); |
91c00924 DW |
654 | BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags)); |
655 | ||
656 | for (i = disks; i--; ) | |
657 | if (i != target) | |
658 | xor_srcs[count++] = sh->dev[i].page; | |
659 | ||
660 | atomic_inc(&sh->count); | |
661 | ||
662 | if (unlikely(count == 1)) | |
663 | tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE, | |
664 | 0, NULL, ops_complete_compute5, sh); | |
665 | else | |
666 | tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, | |
667 | ASYNC_TX_XOR_ZERO_DST, NULL, | |
668 | ops_complete_compute5, sh); | |
669 | ||
91c00924 DW |
670 | return tx; |
671 | } | |
672 | ||
673 | static void ops_complete_prexor(void *stripe_head_ref) | |
674 | { | |
675 | struct stripe_head *sh = stripe_head_ref; | |
676 | ||
e46b272b | 677 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 | 678 | (unsigned long long)sh->sector); |
91c00924 DW |
679 | } |
680 | ||
681 | static struct dma_async_tx_descriptor * | |
682 | ops_run_prexor(struct stripe_head *sh, struct dma_async_tx_descriptor *tx) | |
683 | { | |
684 | /* kernel stack size limits the total number of disks */ | |
685 | int disks = sh->disks; | |
686 | struct page *xor_srcs[disks]; | |
687 | int count = 0, pd_idx = sh->pd_idx, i; | |
688 | ||
689 | /* existing parity data subtracted */ | |
690 | struct page *xor_dest = xor_srcs[count++] = sh->dev[pd_idx].page; | |
691 | ||
e46b272b | 692 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
693 | (unsigned long long)sh->sector); |
694 | ||
695 | for (i = disks; i--; ) { | |
696 | struct r5dev *dev = &sh->dev[i]; | |
697 | /* Only process blocks that are known to be uptodate */ | |
d8ee0728 | 698 | if (test_bit(R5_Wantdrain, &dev->flags)) |
91c00924 DW |
699 | xor_srcs[count++] = dev->page; |
700 | } | |
701 | ||
702 | tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, | |
703 | ASYNC_TX_DEP_ACK | ASYNC_TX_XOR_DROP_DST, tx, | |
704 | ops_complete_prexor, sh); | |
705 | ||
706 | return tx; | |
707 | } | |
708 | ||
709 | static struct dma_async_tx_descriptor * | |
d8ee0728 | 710 | ops_run_biodrain(struct stripe_head *sh, struct dma_async_tx_descriptor *tx) |
91c00924 DW |
711 | { |
712 | int disks = sh->disks; | |
d8ee0728 | 713 | int i; |
91c00924 | 714 | |
e46b272b | 715 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
716 | (unsigned long long)sh->sector); |
717 | ||
718 | for (i = disks; i--; ) { | |
719 | struct r5dev *dev = &sh->dev[i]; | |
720 | struct bio *chosen; | |
91c00924 | 721 | |
d8ee0728 | 722 | if (test_and_clear_bit(R5_Wantdrain, &dev->flags)) { |
91c00924 DW |
723 | struct bio *wbi; |
724 | ||
725 | spin_lock(&sh->lock); | |
726 | chosen = dev->towrite; | |
727 | dev->towrite = NULL; | |
728 | BUG_ON(dev->written); | |
729 | wbi = dev->written = chosen; | |
730 | spin_unlock(&sh->lock); | |
731 | ||
732 | while (wbi && wbi->bi_sector < | |
733 | dev->sector + STRIPE_SECTORS) { | |
734 | tx = async_copy_data(1, wbi, dev->page, | |
735 | dev->sector, tx); | |
736 | wbi = r5_next_bio(wbi, dev->sector); | |
737 | } | |
738 | } | |
739 | } | |
740 | ||
741 | return tx; | |
742 | } | |
743 | ||
744 | static void ops_complete_postxor(void *stripe_head_ref) | |
91c00924 DW |
745 | { |
746 | struct stripe_head *sh = stripe_head_ref; | |
747 | int disks = sh->disks, i, pd_idx = sh->pd_idx; | |
748 | ||
e46b272b | 749 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
750 | (unsigned long long)sh->sector); |
751 | ||
752 | for (i = disks; i--; ) { | |
753 | struct r5dev *dev = &sh->dev[i]; | |
754 | if (dev->written || i == pd_idx) | |
755 | set_bit(R5_UPTODATE, &dev->flags); | |
756 | } | |
757 | ||
d8ee0728 DW |
758 | if (sh->reconstruct_state == reconstruct_state_drain_run) |
759 | sh->reconstruct_state = reconstruct_state_drain_result; | |
760 | else if (sh->reconstruct_state == reconstruct_state_prexor_drain_run) | |
761 | sh->reconstruct_state = reconstruct_state_prexor_drain_result; | |
762 | else { | |
763 | BUG_ON(sh->reconstruct_state != reconstruct_state_run); | |
764 | sh->reconstruct_state = reconstruct_state_result; | |
765 | } | |
91c00924 DW |
766 | |
767 | set_bit(STRIPE_HANDLE, &sh->state); | |
768 | release_stripe(sh); | |
769 | } | |
770 | ||
771 | static void | |
d8ee0728 | 772 | ops_run_postxor(struct stripe_head *sh, struct dma_async_tx_descriptor *tx) |
91c00924 DW |
773 | { |
774 | /* kernel stack size limits the total number of disks */ | |
775 | int disks = sh->disks; | |
776 | struct page *xor_srcs[disks]; | |
777 | ||
778 | int count = 0, pd_idx = sh->pd_idx, i; | |
779 | struct page *xor_dest; | |
d8ee0728 | 780 | int prexor = 0; |
91c00924 | 781 | unsigned long flags; |
91c00924 | 782 | |
e46b272b | 783 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
784 | (unsigned long long)sh->sector); |
785 | ||
786 | /* check if prexor is active which means only process blocks | |
787 | * that are part of a read-modify-write (written) | |
788 | */ | |
d8ee0728 DW |
789 | if (sh->reconstruct_state == reconstruct_state_prexor_drain_run) { |
790 | prexor = 1; | |
91c00924 DW |
791 | xor_dest = xor_srcs[count++] = sh->dev[pd_idx].page; |
792 | for (i = disks; i--; ) { | |
793 | struct r5dev *dev = &sh->dev[i]; | |
794 | if (dev->written) | |
795 | xor_srcs[count++] = dev->page; | |
796 | } | |
797 | } else { | |
798 | xor_dest = sh->dev[pd_idx].page; | |
799 | for (i = disks; i--; ) { | |
800 | struct r5dev *dev = &sh->dev[i]; | |
801 | if (i != pd_idx) | |
802 | xor_srcs[count++] = dev->page; | |
803 | } | |
804 | } | |
805 | ||
91c00924 DW |
806 | /* 1/ if we prexor'd then the dest is reused as a source |
807 | * 2/ if we did not prexor then we are redoing the parity | |
808 | * set ASYNC_TX_XOR_DROP_DST and ASYNC_TX_XOR_ZERO_DST | |
809 | * for the synchronous xor case | |
810 | */ | |
811 | flags = ASYNC_TX_DEP_ACK | ASYNC_TX_ACK | | |
812 | (prexor ? ASYNC_TX_XOR_DROP_DST : ASYNC_TX_XOR_ZERO_DST); | |
813 | ||
814 | atomic_inc(&sh->count); | |
815 | ||
816 | if (unlikely(count == 1)) { | |
817 | flags &= ~(ASYNC_TX_XOR_DROP_DST | ASYNC_TX_XOR_ZERO_DST); | |
818 | tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE, | |
d8ee0728 | 819 | flags, tx, ops_complete_postxor, sh); |
91c00924 DW |
820 | } else |
821 | tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, | |
d8ee0728 | 822 | flags, tx, ops_complete_postxor, sh); |
91c00924 DW |
823 | } |
824 | ||
825 | static void ops_complete_check(void *stripe_head_ref) | |
826 | { | |
827 | struct stripe_head *sh = stripe_head_ref; | |
91c00924 | 828 | |
e46b272b | 829 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
830 | (unsigned long long)sh->sector); |
831 | ||
ecc65c9b | 832 | sh->check_state = check_state_check_result; |
91c00924 DW |
833 | set_bit(STRIPE_HANDLE, &sh->state); |
834 | release_stripe(sh); | |
835 | } | |
836 | ||
837 | static void ops_run_check(struct stripe_head *sh) | |
838 | { | |
839 | /* kernel stack size limits the total number of disks */ | |
840 | int disks = sh->disks; | |
841 | struct page *xor_srcs[disks]; | |
842 | struct dma_async_tx_descriptor *tx; | |
843 | ||
844 | int count = 0, pd_idx = sh->pd_idx, i; | |
845 | struct page *xor_dest = xor_srcs[count++] = sh->dev[pd_idx].page; | |
846 | ||
e46b272b | 847 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
848 | (unsigned long long)sh->sector); |
849 | ||
850 | for (i = disks; i--; ) { | |
851 | struct r5dev *dev = &sh->dev[i]; | |
852 | if (i != pd_idx) | |
853 | xor_srcs[count++] = dev->page; | |
854 | } | |
855 | ||
856 | tx = async_xor_zero_sum(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, | |
857 | &sh->ops.zero_sum_result, 0, NULL, NULL, NULL); | |
858 | ||
91c00924 DW |
859 | atomic_inc(&sh->count); |
860 | tx = async_trigger_callback(ASYNC_TX_DEP_ACK | ASYNC_TX_ACK, tx, | |
861 | ops_complete_check, sh); | |
862 | } | |
863 | ||
600aa109 | 864 | static void raid5_run_ops(struct stripe_head *sh, unsigned long ops_request) |
91c00924 DW |
865 | { |
866 | int overlap_clear = 0, i, disks = sh->disks; | |
867 | struct dma_async_tx_descriptor *tx = NULL; | |
868 | ||
83de75cc | 869 | if (test_bit(STRIPE_OP_BIOFILL, &ops_request)) { |
91c00924 DW |
870 | ops_run_biofill(sh); |
871 | overlap_clear++; | |
872 | } | |
873 | ||
7b3a871e DW |
874 | if (test_bit(STRIPE_OP_COMPUTE_BLK, &ops_request)) { |
875 | tx = ops_run_compute5(sh); | |
876 | /* terminate the chain if postxor is not set to be run */ | |
877 | if (tx && !test_bit(STRIPE_OP_POSTXOR, &ops_request)) | |
878 | async_tx_ack(tx); | |
879 | } | |
91c00924 | 880 | |
600aa109 | 881 | if (test_bit(STRIPE_OP_PREXOR, &ops_request)) |
91c00924 DW |
882 | tx = ops_run_prexor(sh, tx); |
883 | ||
600aa109 | 884 | if (test_bit(STRIPE_OP_BIODRAIN, &ops_request)) { |
d8ee0728 | 885 | tx = ops_run_biodrain(sh, tx); |
91c00924 DW |
886 | overlap_clear++; |
887 | } | |
888 | ||
600aa109 | 889 | if (test_bit(STRIPE_OP_POSTXOR, &ops_request)) |
d8ee0728 | 890 | ops_run_postxor(sh, tx); |
91c00924 | 891 | |
ecc65c9b | 892 | if (test_bit(STRIPE_OP_CHECK, &ops_request)) |
91c00924 DW |
893 | ops_run_check(sh); |
894 | ||
91c00924 DW |
895 | if (overlap_clear) |
896 | for (i = disks; i--; ) { | |
897 | struct r5dev *dev = &sh->dev[i]; | |
898 | if (test_and_clear_bit(R5_Overlap, &dev->flags)) | |
899 | wake_up(&sh->raid_conf->wait_for_overlap); | |
900 | } | |
901 | } | |
902 | ||
3f294f4f | 903 | static int grow_one_stripe(raid5_conf_t *conf) |
1da177e4 LT |
904 | { |
905 | struct stripe_head *sh; | |
3f294f4f N |
906 | sh = kmem_cache_alloc(conf->slab_cache, GFP_KERNEL); |
907 | if (!sh) | |
908 | return 0; | |
909 | memset(sh, 0, sizeof(*sh) + (conf->raid_disks-1)*sizeof(struct r5dev)); | |
910 | sh->raid_conf = conf; | |
911 | spin_lock_init(&sh->lock); | |
912 | ||
913 | if (grow_buffers(sh, conf->raid_disks)) { | |
914 | shrink_buffers(sh, conf->raid_disks); | |
915 | kmem_cache_free(conf->slab_cache, sh); | |
916 | return 0; | |
917 | } | |
7ecaa1e6 | 918 | sh->disks = conf->raid_disks; |
3f294f4f N |
919 | /* we just created an active stripe so... */ |
920 | atomic_set(&sh->count, 1); | |
921 | atomic_inc(&conf->active_stripes); | |
922 | INIT_LIST_HEAD(&sh->lru); | |
923 | release_stripe(sh); | |
924 | return 1; | |
925 | } | |
926 | ||
927 | static int grow_stripes(raid5_conf_t *conf, int num) | |
928 | { | |
e18b890b | 929 | struct kmem_cache *sc; |
1da177e4 LT |
930 | int devs = conf->raid_disks; |
931 | ||
245f46c2 N |
932 | sprintf(conf->cache_name[0], |
933 | "raid%d-%s", conf->level, mdname(conf->mddev)); | |
934 | sprintf(conf->cache_name[1], | |
935 | "raid%d-%s-alt", conf->level, mdname(conf->mddev)); | |
ad01c9e3 N |
936 | conf->active_name = 0; |
937 | sc = kmem_cache_create(conf->cache_name[conf->active_name], | |
1da177e4 | 938 | sizeof(struct stripe_head)+(devs-1)*sizeof(struct r5dev), |
20c2df83 | 939 | 0, 0, NULL); |
1da177e4 LT |
940 | if (!sc) |
941 | return 1; | |
942 | conf->slab_cache = sc; | |
ad01c9e3 | 943 | conf->pool_size = devs; |
16a53ecc | 944 | while (num--) |
3f294f4f | 945 | if (!grow_one_stripe(conf)) |
1da177e4 | 946 | return 1; |
1da177e4 LT |
947 | return 0; |
948 | } | |
29269553 N |
949 | |
950 | #ifdef CONFIG_MD_RAID5_RESHAPE | |
ad01c9e3 N |
951 | static int resize_stripes(raid5_conf_t *conf, int newsize) |
952 | { | |
953 | /* Make all the stripes able to hold 'newsize' devices. | |
954 | * New slots in each stripe get 'page' set to a new page. | |
955 | * | |
956 | * This happens in stages: | |
957 | * 1/ create a new kmem_cache and allocate the required number of | |
958 | * stripe_heads. | |
959 | * 2/ gather all the old stripe_heads and tranfer the pages across | |
960 | * to the new stripe_heads. This will have the side effect of | |
961 | * freezing the array as once all stripe_heads have been collected, | |
962 | * no IO will be possible. Old stripe heads are freed once their | |
963 | * pages have been transferred over, and the old kmem_cache is | |
964 | * freed when all stripes are done. | |
965 | * 3/ reallocate conf->disks to be suitable bigger. If this fails, | |
966 | * we simple return a failre status - no need to clean anything up. | |
967 | * 4/ allocate new pages for the new slots in the new stripe_heads. | |
968 | * If this fails, we don't bother trying the shrink the | |
969 | * stripe_heads down again, we just leave them as they are. | |
970 | * As each stripe_head is processed the new one is released into | |
971 | * active service. | |
972 | * | |
973 | * Once step2 is started, we cannot afford to wait for a write, | |
974 | * so we use GFP_NOIO allocations. | |
975 | */ | |
976 | struct stripe_head *osh, *nsh; | |
977 | LIST_HEAD(newstripes); | |
978 | struct disk_info *ndisks; | |
b5470dc5 | 979 | int err; |
e18b890b | 980 | struct kmem_cache *sc; |
ad01c9e3 N |
981 | int i; |
982 | ||
983 | if (newsize <= conf->pool_size) | |
984 | return 0; /* never bother to shrink */ | |
985 | ||
b5470dc5 DW |
986 | err = md_allow_write(conf->mddev); |
987 | if (err) | |
988 | return err; | |
2a2275d6 | 989 | |
ad01c9e3 N |
990 | /* Step 1 */ |
991 | sc = kmem_cache_create(conf->cache_name[1-conf->active_name], | |
992 | sizeof(struct stripe_head)+(newsize-1)*sizeof(struct r5dev), | |
20c2df83 | 993 | 0, 0, NULL); |
ad01c9e3 N |
994 | if (!sc) |
995 | return -ENOMEM; | |
996 | ||
997 | for (i = conf->max_nr_stripes; i; i--) { | |
998 | nsh = kmem_cache_alloc(sc, GFP_KERNEL); | |
999 | if (!nsh) | |
1000 | break; | |
1001 | ||
1002 | memset(nsh, 0, sizeof(*nsh) + (newsize-1)*sizeof(struct r5dev)); | |
1003 | ||
1004 | nsh->raid_conf = conf; | |
1005 | spin_lock_init(&nsh->lock); | |
1006 | ||
1007 | list_add(&nsh->lru, &newstripes); | |
1008 | } | |
1009 | if (i) { | |
1010 | /* didn't get enough, give up */ | |
1011 | while (!list_empty(&newstripes)) { | |
1012 | nsh = list_entry(newstripes.next, struct stripe_head, lru); | |
1013 | list_del(&nsh->lru); | |
1014 | kmem_cache_free(sc, nsh); | |
1015 | } | |
1016 | kmem_cache_destroy(sc); | |
1017 | return -ENOMEM; | |
1018 | } | |
1019 | /* Step 2 - Must use GFP_NOIO now. | |
1020 | * OK, we have enough stripes, start collecting inactive | |
1021 | * stripes and copying them over | |
1022 | */ | |
1023 | list_for_each_entry(nsh, &newstripes, lru) { | |
1024 | spin_lock_irq(&conf->device_lock); | |
1025 | wait_event_lock_irq(conf->wait_for_stripe, | |
1026 | !list_empty(&conf->inactive_list), | |
1027 | conf->device_lock, | |
b3b46be3 | 1028 | unplug_slaves(conf->mddev) |
ad01c9e3 N |
1029 | ); |
1030 | osh = get_free_stripe(conf); | |
1031 | spin_unlock_irq(&conf->device_lock); | |
1032 | atomic_set(&nsh->count, 1); | |
1033 | for(i=0; i<conf->pool_size; i++) | |
1034 | nsh->dev[i].page = osh->dev[i].page; | |
1035 | for( ; i<newsize; i++) | |
1036 | nsh->dev[i].page = NULL; | |
1037 | kmem_cache_free(conf->slab_cache, osh); | |
1038 | } | |
1039 | kmem_cache_destroy(conf->slab_cache); | |
1040 | ||
1041 | /* Step 3. | |
1042 | * At this point, we are holding all the stripes so the array | |
1043 | * is completely stalled, so now is a good time to resize | |
1044 | * conf->disks. | |
1045 | */ | |
1046 | ndisks = kzalloc(newsize * sizeof(struct disk_info), GFP_NOIO); | |
1047 | if (ndisks) { | |
1048 | for (i=0; i<conf->raid_disks; i++) | |
1049 | ndisks[i] = conf->disks[i]; | |
1050 | kfree(conf->disks); | |
1051 | conf->disks = ndisks; | |
1052 | } else | |
1053 | err = -ENOMEM; | |
1054 | ||
1055 | /* Step 4, return new stripes to service */ | |
1056 | while(!list_empty(&newstripes)) { | |
1057 | nsh = list_entry(newstripes.next, struct stripe_head, lru); | |
1058 | list_del_init(&nsh->lru); | |
1059 | for (i=conf->raid_disks; i < newsize; i++) | |
1060 | if (nsh->dev[i].page == NULL) { | |
1061 | struct page *p = alloc_page(GFP_NOIO); | |
1062 | nsh->dev[i].page = p; | |
1063 | if (!p) | |
1064 | err = -ENOMEM; | |
1065 | } | |
1066 | release_stripe(nsh); | |
1067 | } | |
1068 | /* critical section pass, GFP_NOIO no longer needed */ | |
1069 | ||
1070 | conf->slab_cache = sc; | |
1071 | conf->active_name = 1-conf->active_name; | |
1072 | conf->pool_size = newsize; | |
1073 | return err; | |
1074 | } | |
29269553 | 1075 | #endif |
1da177e4 | 1076 | |
3f294f4f | 1077 | static int drop_one_stripe(raid5_conf_t *conf) |
1da177e4 LT |
1078 | { |
1079 | struct stripe_head *sh; | |
1080 | ||
3f294f4f N |
1081 | spin_lock_irq(&conf->device_lock); |
1082 | sh = get_free_stripe(conf); | |
1083 | spin_unlock_irq(&conf->device_lock); | |
1084 | if (!sh) | |
1085 | return 0; | |
78bafebd | 1086 | BUG_ON(atomic_read(&sh->count)); |
ad01c9e3 | 1087 | shrink_buffers(sh, conf->pool_size); |
3f294f4f N |
1088 | kmem_cache_free(conf->slab_cache, sh); |
1089 | atomic_dec(&conf->active_stripes); | |
1090 | return 1; | |
1091 | } | |
1092 | ||
1093 | static void shrink_stripes(raid5_conf_t *conf) | |
1094 | { | |
1095 | while (drop_one_stripe(conf)) | |
1096 | ; | |
1097 | ||
29fc7e3e N |
1098 | if (conf->slab_cache) |
1099 | kmem_cache_destroy(conf->slab_cache); | |
1da177e4 LT |
1100 | conf->slab_cache = NULL; |
1101 | } | |
1102 | ||
6712ecf8 | 1103 | static void raid5_end_read_request(struct bio * bi, int error) |
1da177e4 | 1104 | { |
99c0fb5f | 1105 | struct stripe_head *sh = bi->bi_private; |
1da177e4 | 1106 | raid5_conf_t *conf = sh->raid_conf; |
7ecaa1e6 | 1107 | int disks = sh->disks, i; |
1da177e4 | 1108 | int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags); |
d6950432 N |
1109 | char b[BDEVNAME_SIZE]; |
1110 | mdk_rdev_t *rdev; | |
1da177e4 | 1111 | |
1da177e4 LT |
1112 | |
1113 | for (i=0 ; i<disks; i++) | |
1114 | if (bi == &sh->dev[i].req) | |
1115 | break; | |
1116 | ||
45b4233c DW |
1117 | pr_debug("end_read_request %llu/%d, count: %d, uptodate %d.\n", |
1118 | (unsigned long long)sh->sector, i, atomic_read(&sh->count), | |
1da177e4 LT |
1119 | uptodate); |
1120 | if (i == disks) { | |
1121 | BUG(); | |
6712ecf8 | 1122 | return; |
1da177e4 LT |
1123 | } |
1124 | ||
1125 | if (uptodate) { | |
1da177e4 | 1126 | set_bit(R5_UPTODATE, &sh->dev[i].flags); |
4e5314b5 | 1127 | if (test_bit(R5_ReadError, &sh->dev[i].flags)) { |
d6950432 | 1128 | rdev = conf->disks[i].rdev; |
6be9d494 BS |
1129 | printk_rl(KERN_INFO "raid5:%s: read error corrected" |
1130 | " (%lu sectors at %llu on %s)\n", | |
1131 | mdname(conf->mddev), STRIPE_SECTORS, | |
1132 | (unsigned long long)(sh->sector | |
1133 | + rdev->data_offset), | |
1134 | bdevname(rdev->bdev, b)); | |
4e5314b5 N |
1135 | clear_bit(R5_ReadError, &sh->dev[i].flags); |
1136 | clear_bit(R5_ReWrite, &sh->dev[i].flags); | |
1137 | } | |
ba22dcbf N |
1138 | if (atomic_read(&conf->disks[i].rdev->read_errors)) |
1139 | atomic_set(&conf->disks[i].rdev->read_errors, 0); | |
1da177e4 | 1140 | } else { |
d6950432 | 1141 | const char *bdn = bdevname(conf->disks[i].rdev->bdev, b); |
ba22dcbf | 1142 | int retry = 0; |
d6950432 N |
1143 | rdev = conf->disks[i].rdev; |
1144 | ||
1da177e4 | 1145 | clear_bit(R5_UPTODATE, &sh->dev[i].flags); |
d6950432 | 1146 | atomic_inc(&rdev->read_errors); |
ba22dcbf | 1147 | if (conf->mddev->degraded) |
6be9d494 BS |
1148 | printk_rl(KERN_WARNING |
1149 | "raid5:%s: read error not correctable " | |
1150 | "(sector %llu on %s).\n", | |
1151 | mdname(conf->mddev), | |
1152 | (unsigned long long)(sh->sector | |
1153 | + rdev->data_offset), | |
1154 | bdn); | |
ba22dcbf | 1155 | else if (test_bit(R5_ReWrite, &sh->dev[i].flags)) |
4e5314b5 | 1156 | /* Oh, no!!! */ |
6be9d494 BS |
1157 | printk_rl(KERN_WARNING |
1158 | "raid5:%s: read error NOT corrected!! " | |
1159 | "(sector %llu on %s).\n", | |
1160 | mdname(conf->mddev), | |
1161 | (unsigned long long)(sh->sector | |
1162 | + rdev->data_offset), | |
1163 | bdn); | |
d6950432 | 1164 | else if (atomic_read(&rdev->read_errors) |
ba22dcbf | 1165 | > conf->max_nr_stripes) |
14f8d26b | 1166 | printk(KERN_WARNING |
d6950432 N |
1167 | "raid5:%s: Too many read errors, failing device %s.\n", |
1168 | mdname(conf->mddev), bdn); | |
ba22dcbf N |
1169 | else |
1170 | retry = 1; | |
1171 | if (retry) | |
1172 | set_bit(R5_ReadError, &sh->dev[i].flags); | |
1173 | else { | |
4e5314b5 N |
1174 | clear_bit(R5_ReadError, &sh->dev[i].flags); |
1175 | clear_bit(R5_ReWrite, &sh->dev[i].flags); | |
d6950432 | 1176 | md_error(conf->mddev, rdev); |
ba22dcbf | 1177 | } |
1da177e4 LT |
1178 | } |
1179 | rdev_dec_pending(conf->disks[i].rdev, conf->mddev); | |
1da177e4 LT |
1180 | clear_bit(R5_LOCKED, &sh->dev[i].flags); |
1181 | set_bit(STRIPE_HANDLE, &sh->state); | |
1182 | release_stripe(sh); | |
1da177e4 LT |
1183 | } |
1184 | ||
d710e138 | 1185 | static void raid5_end_write_request(struct bio *bi, int error) |
1da177e4 | 1186 | { |
99c0fb5f | 1187 | struct stripe_head *sh = bi->bi_private; |
1da177e4 | 1188 | raid5_conf_t *conf = sh->raid_conf; |
7ecaa1e6 | 1189 | int disks = sh->disks, i; |
1da177e4 LT |
1190 | int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags); |
1191 | ||
1da177e4 LT |
1192 | for (i=0 ; i<disks; i++) |
1193 | if (bi == &sh->dev[i].req) | |
1194 | break; | |
1195 | ||
45b4233c | 1196 | pr_debug("end_write_request %llu/%d, count %d, uptodate: %d.\n", |
1da177e4 LT |
1197 | (unsigned long long)sh->sector, i, atomic_read(&sh->count), |
1198 | uptodate); | |
1199 | if (i == disks) { | |
1200 | BUG(); | |
6712ecf8 | 1201 | return; |
1da177e4 LT |
1202 | } |
1203 | ||
1da177e4 LT |
1204 | if (!uptodate) |
1205 | md_error(conf->mddev, conf->disks[i].rdev); | |
1206 | ||
1207 | rdev_dec_pending(conf->disks[i].rdev, conf->mddev); | |
1208 | ||
1209 | clear_bit(R5_LOCKED, &sh->dev[i].flags); | |
1210 | set_bit(STRIPE_HANDLE, &sh->state); | |
c04be0aa | 1211 | release_stripe(sh); |
1da177e4 LT |
1212 | } |
1213 | ||
1214 | ||
784052ec | 1215 | static sector_t compute_blocknr(struct stripe_head *sh, int i, int previous); |
1da177e4 | 1216 | |
784052ec | 1217 | static void raid5_build_block(struct stripe_head *sh, int i, int previous) |
1da177e4 LT |
1218 | { |
1219 | struct r5dev *dev = &sh->dev[i]; | |
1220 | ||
1221 | bio_init(&dev->req); | |
1222 | dev->req.bi_io_vec = &dev->vec; | |
1223 | dev->req.bi_vcnt++; | |
1224 | dev->req.bi_max_vecs++; | |
1225 | dev->vec.bv_page = dev->page; | |
1226 | dev->vec.bv_len = STRIPE_SIZE; | |
1227 | dev->vec.bv_offset = 0; | |
1228 | ||
1229 | dev->req.bi_sector = sh->sector; | |
1230 | dev->req.bi_private = sh; | |
1231 | ||
1232 | dev->flags = 0; | |
784052ec | 1233 | dev->sector = compute_blocknr(sh, i, previous); |
1da177e4 LT |
1234 | } |
1235 | ||
1236 | static void error(mddev_t *mddev, mdk_rdev_t *rdev) | |
1237 | { | |
1238 | char b[BDEVNAME_SIZE]; | |
1239 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; | |
45b4233c | 1240 | pr_debug("raid5: error called\n"); |
1da177e4 | 1241 | |
b2d444d7 | 1242 | if (!test_bit(Faulty, &rdev->flags)) { |
850b2b42 | 1243 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
c04be0aa N |
1244 | if (test_and_clear_bit(In_sync, &rdev->flags)) { |
1245 | unsigned long flags; | |
1246 | spin_lock_irqsave(&conf->device_lock, flags); | |
1da177e4 | 1247 | mddev->degraded++; |
c04be0aa | 1248 | spin_unlock_irqrestore(&conf->device_lock, flags); |
1da177e4 LT |
1249 | /* |
1250 | * if recovery was running, make sure it aborts. | |
1251 | */ | |
dfc70645 | 1252 | set_bit(MD_RECOVERY_INTR, &mddev->recovery); |
1da177e4 | 1253 | } |
b2d444d7 | 1254 | set_bit(Faulty, &rdev->flags); |
d710e138 N |
1255 | printk(KERN_ALERT |
1256 | "raid5: Disk failure on %s, disabling device.\n" | |
1257 | "raid5: Operation continuing on %d devices.\n", | |
1258 | bdevname(rdev->bdev,b), conf->raid_disks - mddev->degraded); | |
1da177e4 | 1259 | } |
16a53ecc | 1260 | } |
1da177e4 LT |
1261 | |
1262 | /* | |
1263 | * Input: a 'big' sector number, | |
1264 | * Output: index of the data and parity disk, and the sector # in them. | |
1265 | */ | |
112bf897 | 1266 | static sector_t raid5_compute_sector(raid5_conf_t *conf, sector_t r_sector, |
911d4ee8 N |
1267 | int previous, int *dd_idx, |
1268 | struct stripe_head *sh) | |
1da177e4 LT |
1269 | { |
1270 | long stripe; | |
1271 | unsigned long chunk_number; | |
1272 | unsigned int chunk_offset; | |
911d4ee8 | 1273 | int pd_idx, qd_idx; |
67cc2b81 | 1274 | int ddf_layout = 0; |
1da177e4 | 1275 | sector_t new_sector; |
784052ec N |
1276 | int sectors_per_chunk = previous ? (conf->prev_chunk >> 9) |
1277 | : (conf->chunk_size >> 9); | |
112bf897 N |
1278 | int raid_disks = previous ? conf->previous_raid_disks |
1279 | : conf->raid_disks; | |
1280 | int data_disks = raid_disks - conf->max_degraded; | |
1da177e4 LT |
1281 | |
1282 | /* First compute the information on this sector */ | |
1283 | ||
1284 | /* | |
1285 | * Compute the chunk number and the sector offset inside the chunk | |
1286 | */ | |
1287 | chunk_offset = sector_div(r_sector, sectors_per_chunk); | |
1288 | chunk_number = r_sector; | |
1289 | BUG_ON(r_sector != chunk_number); | |
1290 | ||
1291 | /* | |
1292 | * Compute the stripe number | |
1293 | */ | |
1294 | stripe = chunk_number / data_disks; | |
1295 | ||
1296 | /* | |
1297 | * Compute the data disk and parity disk indexes inside the stripe | |
1298 | */ | |
1299 | *dd_idx = chunk_number % data_disks; | |
1300 | ||
1301 | /* | |
1302 | * Select the parity disk based on the user selected algorithm. | |
1303 | */ | |
911d4ee8 | 1304 | pd_idx = qd_idx = ~0; |
16a53ecc N |
1305 | switch(conf->level) { |
1306 | case 4: | |
911d4ee8 | 1307 | pd_idx = data_disks; |
16a53ecc N |
1308 | break; |
1309 | case 5: | |
1310 | switch (conf->algorithm) { | |
1da177e4 | 1311 | case ALGORITHM_LEFT_ASYMMETRIC: |
911d4ee8 N |
1312 | pd_idx = data_disks - stripe % raid_disks; |
1313 | if (*dd_idx >= pd_idx) | |
1da177e4 LT |
1314 | (*dd_idx)++; |
1315 | break; | |
1316 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
911d4ee8 N |
1317 | pd_idx = stripe % raid_disks; |
1318 | if (*dd_idx >= pd_idx) | |
1da177e4 LT |
1319 | (*dd_idx)++; |
1320 | break; | |
1321 | case ALGORITHM_LEFT_SYMMETRIC: | |
911d4ee8 N |
1322 | pd_idx = data_disks - stripe % raid_disks; |
1323 | *dd_idx = (pd_idx + 1 + *dd_idx) % raid_disks; | |
1da177e4 LT |
1324 | break; |
1325 | case ALGORITHM_RIGHT_SYMMETRIC: | |
911d4ee8 N |
1326 | pd_idx = stripe % raid_disks; |
1327 | *dd_idx = (pd_idx + 1 + *dd_idx) % raid_disks; | |
1da177e4 | 1328 | break; |
99c0fb5f N |
1329 | case ALGORITHM_PARITY_0: |
1330 | pd_idx = 0; | |
1331 | (*dd_idx)++; | |
1332 | break; | |
1333 | case ALGORITHM_PARITY_N: | |
1334 | pd_idx = data_disks; | |
1335 | break; | |
1da177e4 | 1336 | default: |
14f8d26b | 1337 | printk(KERN_ERR "raid5: unsupported algorithm %d\n", |
1da177e4 | 1338 | conf->algorithm); |
99c0fb5f | 1339 | BUG(); |
16a53ecc N |
1340 | } |
1341 | break; | |
1342 | case 6: | |
1343 | ||
16a53ecc N |
1344 | switch (conf->algorithm) { |
1345 | case ALGORITHM_LEFT_ASYMMETRIC: | |
911d4ee8 N |
1346 | pd_idx = raid_disks - 1 - (stripe % raid_disks); |
1347 | qd_idx = pd_idx + 1; | |
1348 | if (pd_idx == raid_disks-1) { | |
99c0fb5f | 1349 | (*dd_idx)++; /* Q D D D P */ |
911d4ee8 N |
1350 | qd_idx = 0; |
1351 | } else if (*dd_idx >= pd_idx) | |
16a53ecc N |
1352 | (*dd_idx) += 2; /* D D P Q D */ |
1353 | break; | |
1354 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
911d4ee8 N |
1355 | pd_idx = stripe % raid_disks; |
1356 | qd_idx = pd_idx + 1; | |
1357 | if (pd_idx == raid_disks-1) { | |
99c0fb5f | 1358 | (*dd_idx)++; /* Q D D D P */ |
911d4ee8 N |
1359 | qd_idx = 0; |
1360 | } else if (*dd_idx >= pd_idx) | |
16a53ecc N |
1361 | (*dd_idx) += 2; /* D D P Q D */ |
1362 | break; | |
1363 | case ALGORITHM_LEFT_SYMMETRIC: | |
911d4ee8 N |
1364 | pd_idx = raid_disks - 1 - (stripe % raid_disks); |
1365 | qd_idx = (pd_idx + 1) % raid_disks; | |
1366 | *dd_idx = (pd_idx + 2 + *dd_idx) % raid_disks; | |
16a53ecc N |
1367 | break; |
1368 | case ALGORITHM_RIGHT_SYMMETRIC: | |
911d4ee8 N |
1369 | pd_idx = stripe % raid_disks; |
1370 | qd_idx = (pd_idx + 1) % raid_disks; | |
1371 | *dd_idx = (pd_idx + 2 + *dd_idx) % raid_disks; | |
16a53ecc | 1372 | break; |
99c0fb5f N |
1373 | |
1374 | case ALGORITHM_PARITY_0: | |
1375 | pd_idx = 0; | |
1376 | qd_idx = 1; | |
1377 | (*dd_idx) += 2; | |
1378 | break; | |
1379 | case ALGORITHM_PARITY_N: | |
1380 | pd_idx = data_disks; | |
1381 | qd_idx = data_disks + 1; | |
1382 | break; | |
1383 | ||
1384 | case ALGORITHM_ROTATING_ZERO_RESTART: | |
1385 | /* Exactly the same as RIGHT_ASYMMETRIC, but or | |
1386 | * of blocks for computing Q is different. | |
1387 | */ | |
1388 | pd_idx = stripe % raid_disks; | |
1389 | qd_idx = pd_idx + 1; | |
1390 | if (pd_idx == raid_disks-1) { | |
1391 | (*dd_idx)++; /* Q D D D P */ | |
1392 | qd_idx = 0; | |
1393 | } else if (*dd_idx >= pd_idx) | |
1394 | (*dd_idx) += 2; /* D D P Q D */ | |
67cc2b81 | 1395 | ddf_layout = 1; |
99c0fb5f N |
1396 | break; |
1397 | ||
1398 | case ALGORITHM_ROTATING_N_RESTART: | |
1399 | /* Same a left_asymmetric, by first stripe is | |
1400 | * D D D P Q rather than | |
1401 | * Q D D D P | |
1402 | */ | |
1403 | pd_idx = raid_disks - 1 - ((stripe + 1) % raid_disks); | |
1404 | qd_idx = pd_idx + 1; | |
1405 | if (pd_idx == raid_disks-1) { | |
1406 | (*dd_idx)++; /* Q D D D P */ | |
1407 | qd_idx = 0; | |
1408 | } else if (*dd_idx >= pd_idx) | |
1409 | (*dd_idx) += 2; /* D D P Q D */ | |
67cc2b81 | 1410 | ddf_layout = 1; |
99c0fb5f N |
1411 | break; |
1412 | ||
1413 | case ALGORITHM_ROTATING_N_CONTINUE: | |
1414 | /* Same as left_symmetric but Q is before P */ | |
1415 | pd_idx = raid_disks - 1 - (stripe % raid_disks); | |
1416 | qd_idx = (pd_idx + raid_disks - 1) % raid_disks; | |
1417 | *dd_idx = (pd_idx + 1 + *dd_idx) % raid_disks; | |
67cc2b81 | 1418 | ddf_layout = 1; |
99c0fb5f N |
1419 | break; |
1420 | ||
1421 | case ALGORITHM_LEFT_ASYMMETRIC_6: | |
1422 | /* RAID5 left_asymmetric, with Q on last device */ | |
1423 | pd_idx = data_disks - stripe % (raid_disks-1); | |
1424 | if (*dd_idx >= pd_idx) | |
1425 | (*dd_idx)++; | |
1426 | qd_idx = raid_disks - 1; | |
1427 | break; | |
1428 | ||
1429 | case ALGORITHM_RIGHT_ASYMMETRIC_6: | |
1430 | pd_idx = stripe % (raid_disks-1); | |
1431 | if (*dd_idx >= pd_idx) | |
1432 | (*dd_idx)++; | |
1433 | qd_idx = raid_disks - 1; | |
1434 | break; | |
1435 | ||
1436 | case ALGORITHM_LEFT_SYMMETRIC_6: | |
1437 | pd_idx = data_disks - stripe % (raid_disks-1); | |
1438 | *dd_idx = (pd_idx + 1 + *dd_idx) % (raid_disks-1); | |
1439 | qd_idx = raid_disks - 1; | |
1440 | break; | |
1441 | ||
1442 | case ALGORITHM_RIGHT_SYMMETRIC_6: | |
1443 | pd_idx = stripe % (raid_disks-1); | |
1444 | *dd_idx = (pd_idx + 1 + *dd_idx) % (raid_disks-1); | |
1445 | qd_idx = raid_disks - 1; | |
1446 | break; | |
1447 | ||
1448 | case ALGORITHM_PARITY_0_6: | |
1449 | pd_idx = 0; | |
1450 | (*dd_idx)++; | |
1451 | qd_idx = raid_disks - 1; | |
1452 | break; | |
1453 | ||
1454 | ||
16a53ecc | 1455 | default: |
d710e138 N |
1456 | printk(KERN_CRIT "raid6: unsupported algorithm %d\n", |
1457 | conf->algorithm); | |
99c0fb5f | 1458 | BUG(); |
16a53ecc N |
1459 | } |
1460 | break; | |
1da177e4 LT |
1461 | } |
1462 | ||
911d4ee8 N |
1463 | if (sh) { |
1464 | sh->pd_idx = pd_idx; | |
1465 | sh->qd_idx = qd_idx; | |
67cc2b81 | 1466 | sh->ddf_layout = ddf_layout; |
911d4ee8 | 1467 | } |
1da177e4 LT |
1468 | /* |
1469 | * Finally, compute the new sector number | |
1470 | */ | |
1471 | new_sector = (sector_t)stripe * sectors_per_chunk + chunk_offset; | |
1472 | return new_sector; | |
1473 | } | |
1474 | ||
1475 | ||
784052ec | 1476 | static sector_t compute_blocknr(struct stripe_head *sh, int i, int previous) |
1da177e4 LT |
1477 | { |
1478 | raid5_conf_t *conf = sh->raid_conf; | |
b875e531 N |
1479 | int raid_disks = sh->disks; |
1480 | int data_disks = raid_disks - conf->max_degraded; | |
1da177e4 | 1481 | sector_t new_sector = sh->sector, check; |
784052ec N |
1482 | int sectors_per_chunk = previous ? (conf->prev_chunk >> 9) |
1483 | : (conf->chunk_size >> 9); | |
1da177e4 LT |
1484 | sector_t stripe; |
1485 | int chunk_offset; | |
911d4ee8 | 1486 | int chunk_number, dummy1, dd_idx = i; |
1da177e4 | 1487 | sector_t r_sector; |
911d4ee8 | 1488 | struct stripe_head sh2; |
1da177e4 | 1489 | |
16a53ecc | 1490 | |
1da177e4 LT |
1491 | chunk_offset = sector_div(new_sector, sectors_per_chunk); |
1492 | stripe = new_sector; | |
1493 | BUG_ON(new_sector != stripe); | |
1494 | ||
16a53ecc N |
1495 | if (i == sh->pd_idx) |
1496 | return 0; | |
1497 | switch(conf->level) { | |
1498 | case 4: break; | |
1499 | case 5: | |
1500 | switch (conf->algorithm) { | |
1da177e4 LT |
1501 | case ALGORITHM_LEFT_ASYMMETRIC: |
1502 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
1503 | if (i > sh->pd_idx) | |
1504 | i--; | |
1505 | break; | |
1506 | case ALGORITHM_LEFT_SYMMETRIC: | |
1507 | case ALGORITHM_RIGHT_SYMMETRIC: | |
1508 | if (i < sh->pd_idx) | |
1509 | i += raid_disks; | |
1510 | i -= (sh->pd_idx + 1); | |
1511 | break; | |
99c0fb5f N |
1512 | case ALGORITHM_PARITY_0: |
1513 | i -= 1; | |
1514 | break; | |
1515 | case ALGORITHM_PARITY_N: | |
1516 | break; | |
1da177e4 | 1517 | default: |
14f8d26b | 1518 | printk(KERN_ERR "raid5: unsupported algorithm %d\n", |
16a53ecc | 1519 | conf->algorithm); |
99c0fb5f | 1520 | BUG(); |
16a53ecc N |
1521 | } |
1522 | break; | |
1523 | case 6: | |
d0dabf7e | 1524 | if (i == sh->qd_idx) |
16a53ecc N |
1525 | return 0; /* It is the Q disk */ |
1526 | switch (conf->algorithm) { | |
1527 | case ALGORITHM_LEFT_ASYMMETRIC: | |
1528 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
99c0fb5f N |
1529 | case ALGORITHM_ROTATING_ZERO_RESTART: |
1530 | case ALGORITHM_ROTATING_N_RESTART: | |
1531 | if (sh->pd_idx == raid_disks-1) | |
1532 | i--; /* Q D D D P */ | |
16a53ecc N |
1533 | else if (i > sh->pd_idx) |
1534 | i -= 2; /* D D P Q D */ | |
1535 | break; | |
1536 | case ALGORITHM_LEFT_SYMMETRIC: | |
1537 | case ALGORITHM_RIGHT_SYMMETRIC: | |
1538 | if (sh->pd_idx == raid_disks-1) | |
1539 | i--; /* Q D D D P */ | |
1540 | else { | |
1541 | /* D D P Q D */ | |
1542 | if (i < sh->pd_idx) | |
1543 | i += raid_disks; | |
1544 | i -= (sh->pd_idx + 2); | |
1545 | } | |
1546 | break; | |
99c0fb5f N |
1547 | case ALGORITHM_PARITY_0: |
1548 | i -= 2; | |
1549 | break; | |
1550 | case ALGORITHM_PARITY_N: | |
1551 | break; | |
1552 | case ALGORITHM_ROTATING_N_CONTINUE: | |
1553 | if (sh->pd_idx == 0) | |
1554 | i--; /* P D D D Q */ | |
1555 | else if (i > sh->pd_idx) | |
1556 | i -= 2; /* D D Q P D */ | |
1557 | break; | |
1558 | case ALGORITHM_LEFT_ASYMMETRIC_6: | |
1559 | case ALGORITHM_RIGHT_ASYMMETRIC_6: | |
1560 | if (i > sh->pd_idx) | |
1561 | i--; | |
1562 | break; | |
1563 | case ALGORITHM_LEFT_SYMMETRIC_6: | |
1564 | case ALGORITHM_RIGHT_SYMMETRIC_6: | |
1565 | if (i < sh->pd_idx) | |
1566 | i += data_disks + 1; | |
1567 | i -= (sh->pd_idx + 1); | |
1568 | break; | |
1569 | case ALGORITHM_PARITY_0_6: | |
1570 | i -= 1; | |
1571 | break; | |
16a53ecc | 1572 | default: |
d710e138 N |
1573 | printk(KERN_CRIT "raid6: unsupported algorithm %d\n", |
1574 | conf->algorithm); | |
99c0fb5f | 1575 | BUG(); |
16a53ecc N |
1576 | } |
1577 | break; | |
1da177e4 LT |
1578 | } |
1579 | ||
1580 | chunk_number = stripe * data_disks + i; | |
1581 | r_sector = (sector_t)chunk_number * sectors_per_chunk + chunk_offset; | |
1582 | ||
112bf897 | 1583 | check = raid5_compute_sector(conf, r_sector, |
784052ec | 1584 | previous, &dummy1, &sh2); |
911d4ee8 N |
1585 | if (check != sh->sector || dummy1 != dd_idx || sh2.pd_idx != sh->pd_idx |
1586 | || sh2.qd_idx != sh->qd_idx) { | |
14f8d26b | 1587 | printk(KERN_ERR "compute_blocknr: map not correct\n"); |
1da177e4 LT |
1588 | return 0; |
1589 | } | |
1590 | return r_sector; | |
1591 | } | |
1592 | ||
1593 | ||
1594 | ||
1595 | /* | |
16a53ecc N |
1596 | * Copy data between a page in the stripe cache, and one or more bion |
1597 | * The page could align with the middle of the bio, or there could be | |
1598 | * several bion, each with several bio_vecs, which cover part of the page | |
1599 | * Multiple bion are linked together on bi_next. There may be extras | |
1600 | * at the end of this list. We ignore them. | |
1da177e4 LT |
1601 | */ |
1602 | static void copy_data(int frombio, struct bio *bio, | |
1603 | struct page *page, | |
1604 | sector_t sector) | |
1605 | { | |
1606 | char *pa = page_address(page); | |
1607 | struct bio_vec *bvl; | |
1608 | int i; | |
1609 | int page_offset; | |
1610 | ||
1611 | if (bio->bi_sector >= sector) | |
1612 | page_offset = (signed)(bio->bi_sector - sector) * 512; | |
1613 | else | |
1614 | page_offset = (signed)(sector - bio->bi_sector) * -512; | |
1615 | bio_for_each_segment(bvl, bio, i) { | |
1616 | int len = bio_iovec_idx(bio,i)->bv_len; | |
1617 | int clen; | |
1618 | int b_offset = 0; | |
1619 | ||
1620 | if (page_offset < 0) { | |
1621 | b_offset = -page_offset; | |
1622 | page_offset += b_offset; | |
1623 | len -= b_offset; | |
1624 | } | |
1625 | ||
1626 | if (len > 0 && page_offset + len > STRIPE_SIZE) | |
1627 | clen = STRIPE_SIZE - page_offset; | |
1628 | else clen = len; | |
16a53ecc | 1629 | |
1da177e4 LT |
1630 | if (clen > 0) { |
1631 | char *ba = __bio_kmap_atomic(bio, i, KM_USER0); | |
1632 | if (frombio) | |
1633 | memcpy(pa+page_offset, ba+b_offset, clen); | |
1634 | else | |
1635 | memcpy(ba+b_offset, pa+page_offset, clen); | |
1636 | __bio_kunmap_atomic(ba, KM_USER0); | |
1637 | } | |
1638 | if (clen < len) /* hit end of page */ | |
1639 | break; | |
1640 | page_offset += len; | |
1641 | } | |
1642 | } | |
1643 | ||
9bc89cd8 DW |
1644 | #define check_xor() do { \ |
1645 | if (count == MAX_XOR_BLOCKS) { \ | |
1646 | xor_blocks(count, STRIPE_SIZE, dest, ptr);\ | |
1647 | count = 0; \ | |
1648 | } \ | |
1da177e4 LT |
1649 | } while(0) |
1650 | ||
16a53ecc N |
1651 | static void compute_parity6(struct stripe_head *sh, int method) |
1652 | { | |
bff61975 | 1653 | raid5_conf_t *conf = sh->raid_conf; |
d0dabf7e | 1654 | int i, pd_idx, qd_idx, d0_idx, disks = sh->disks, count; |
67cc2b81 | 1655 | int syndrome_disks = sh->ddf_layout ? disks : (disks - 2); |
16a53ecc N |
1656 | struct bio *chosen; |
1657 | /**** FIX THIS: This could be very bad if disks is close to 256 ****/ | |
67cc2b81 | 1658 | void *ptrs[syndrome_disks+2]; |
16a53ecc | 1659 | |
d0dabf7e N |
1660 | pd_idx = sh->pd_idx; |
1661 | qd_idx = sh->qd_idx; | |
1662 | d0_idx = raid6_d0(sh); | |
16a53ecc | 1663 | |
45b4233c | 1664 | pr_debug("compute_parity, stripe %llu, method %d\n", |
16a53ecc N |
1665 | (unsigned long long)sh->sector, method); |
1666 | ||
1667 | switch(method) { | |
1668 | case READ_MODIFY_WRITE: | |
1669 | BUG(); /* READ_MODIFY_WRITE N/A for RAID-6 */ | |
1670 | case RECONSTRUCT_WRITE: | |
1671 | for (i= disks; i-- ;) | |
1672 | if ( i != pd_idx && i != qd_idx && sh->dev[i].towrite ) { | |
1673 | chosen = sh->dev[i].towrite; | |
1674 | sh->dev[i].towrite = NULL; | |
1675 | ||
1676 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) | |
1677 | wake_up(&conf->wait_for_overlap); | |
1678 | ||
52e5f9d1 | 1679 | BUG_ON(sh->dev[i].written); |
16a53ecc N |
1680 | sh->dev[i].written = chosen; |
1681 | } | |
1682 | break; | |
1683 | case CHECK_PARITY: | |
1684 | BUG(); /* Not implemented yet */ | |
1685 | } | |
1686 | ||
1687 | for (i = disks; i--;) | |
1688 | if (sh->dev[i].written) { | |
1689 | sector_t sector = sh->dev[i].sector; | |
1690 | struct bio *wbi = sh->dev[i].written; | |
1691 | while (wbi && wbi->bi_sector < sector + STRIPE_SECTORS) { | |
1692 | copy_data(1, wbi, sh->dev[i].page, sector); | |
1693 | wbi = r5_next_bio(wbi, sector); | |
1694 | } | |
1695 | ||
1696 | set_bit(R5_LOCKED, &sh->dev[i].flags); | |
1697 | set_bit(R5_UPTODATE, &sh->dev[i].flags); | |
1698 | } | |
1699 | ||
d0dabf7e | 1700 | /* Note that unlike RAID-5, the ordering of the disks matters greatly.*/ |
67cc2b81 N |
1701 | |
1702 | for (i = 0; i < disks; i++) | |
1703 | ptrs[i] = (void *)raid6_empty_zero_page; | |
1704 | ||
d0dabf7e N |
1705 | count = 0; |
1706 | i = d0_idx; | |
1707 | do { | |
67cc2b81 N |
1708 | int slot = raid6_idx_to_slot(i, sh, &count, syndrome_disks); |
1709 | ||
d0dabf7e | 1710 | ptrs[slot] = page_address(sh->dev[i].page); |
67cc2b81 | 1711 | if (slot < syndrome_disks && |
d0dabf7e N |
1712 | !test_bit(R5_UPTODATE, &sh->dev[i].flags)) { |
1713 | printk(KERN_ERR "block %d/%d not uptodate " | |
1714 | "on parity calc\n", i, count); | |
1715 | BUG(); | |
1716 | } | |
67cc2b81 | 1717 | |
d0dabf7e N |
1718 | i = raid6_next_disk(i, disks); |
1719 | } while (i != d0_idx); | |
67cc2b81 | 1720 | BUG_ON(count != syndrome_disks); |
16a53ecc | 1721 | |
67cc2b81 | 1722 | raid6_call.gen_syndrome(syndrome_disks+2, STRIPE_SIZE, ptrs); |
16a53ecc N |
1723 | |
1724 | switch(method) { | |
1725 | case RECONSTRUCT_WRITE: | |
1726 | set_bit(R5_UPTODATE, &sh->dev[pd_idx].flags); | |
1727 | set_bit(R5_UPTODATE, &sh->dev[qd_idx].flags); | |
1728 | set_bit(R5_LOCKED, &sh->dev[pd_idx].flags); | |
1729 | set_bit(R5_LOCKED, &sh->dev[qd_idx].flags); | |
1730 | break; | |
1731 | case UPDATE_PARITY: | |
1732 | set_bit(R5_UPTODATE, &sh->dev[pd_idx].flags); | |
1733 | set_bit(R5_UPTODATE, &sh->dev[qd_idx].flags); | |
1734 | break; | |
1735 | } | |
1736 | } | |
1737 | ||
1738 | ||
1739 | /* Compute one missing block */ | |
1740 | static void compute_block_1(struct stripe_head *sh, int dd_idx, int nozero) | |
1741 | { | |
f416885e | 1742 | int i, count, disks = sh->disks; |
9bc89cd8 | 1743 | void *ptr[MAX_XOR_BLOCKS], *dest, *p; |
d0dabf7e | 1744 | int qd_idx = sh->qd_idx; |
16a53ecc | 1745 | |
45b4233c | 1746 | pr_debug("compute_block_1, stripe %llu, idx %d\n", |
16a53ecc N |
1747 | (unsigned long long)sh->sector, dd_idx); |
1748 | ||
1749 | if ( dd_idx == qd_idx ) { | |
1750 | /* We're actually computing the Q drive */ | |
1751 | compute_parity6(sh, UPDATE_PARITY); | |
1752 | } else { | |
9bc89cd8 DW |
1753 | dest = page_address(sh->dev[dd_idx].page); |
1754 | if (!nozero) memset(dest, 0, STRIPE_SIZE); | |
1755 | count = 0; | |
16a53ecc N |
1756 | for (i = disks ; i--; ) { |
1757 | if (i == dd_idx || i == qd_idx) | |
1758 | continue; | |
1759 | p = page_address(sh->dev[i].page); | |
1760 | if (test_bit(R5_UPTODATE, &sh->dev[i].flags)) | |
1761 | ptr[count++] = p; | |
1762 | else | |
1763 | printk("compute_block() %d, stripe %llu, %d" | |
1764 | " not present\n", dd_idx, | |
1765 | (unsigned long long)sh->sector, i); | |
1766 | ||
1767 | check_xor(); | |
1768 | } | |
9bc89cd8 DW |
1769 | if (count) |
1770 | xor_blocks(count, STRIPE_SIZE, dest, ptr); | |
16a53ecc N |
1771 | if (!nozero) set_bit(R5_UPTODATE, &sh->dev[dd_idx].flags); |
1772 | else clear_bit(R5_UPTODATE, &sh->dev[dd_idx].flags); | |
1773 | } | |
1774 | } | |
1775 | ||
1776 | /* Compute two missing blocks */ | |
1777 | static void compute_block_2(struct stripe_head *sh, int dd_idx1, int dd_idx2) | |
1778 | { | |
f416885e | 1779 | int i, count, disks = sh->disks; |
67cc2b81 | 1780 | int syndrome_disks = sh->ddf_layout ? disks : disks-2; |
d0dabf7e N |
1781 | int d0_idx = raid6_d0(sh); |
1782 | int faila = -1, failb = -1; | |
1783 | /**** FIX THIS: This could be very bad if disks is close to 256 ****/ | |
67cc2b81 | 1784 | void *ptrs[syndrome_disks+2]; |
16a53ecc | 1785 | |
67cc2b81 N |
1786 | for (i = 0; i < disks ; i++) |
1787 | ptrs[i] = (void *)raid6_empty_zero_page; | |
d0dabf7e N |
1788 | count = 0; |
1789 | i = d0_idx; | |
1790 | do { | |
67cc2b81 N |
1791 | int slot = raid6_idx_to_slot(i, sh, &count, syndrome_disks); |
1792 | ||
d0dabf7e | 1793 | ptrs[slot] = page_address(sh->dev[i].page); |
67cc2b81 | 1794 | |
d0dabf7e N |
1795 | if (i == dd_idx1) |
1796 | faila = slot; | |
1797 | if (i == dd_idx2) | |
1798 | failb = slot; | |
1799 | i = raid6_next_disk(i, disks); | |
1800 | } while (i != d0_idx); | |
67cc2b81 | 1801 | BUG_ON(count != syndrome_disks); |
16a53ecc N |
1802 | |
1803 | BUG_ON(faila == failb); | |
1804 | if ( failb < faila ) { int tmp = faila; faila = failb; failb = tmp; } | |
1805 | ||
45b4233c | 1806 | pr_debug("compute_block_2, stripe %llu, idx %d,%d (%d,%d)\n", |
d0dabf7e N |
1807 | (unsigned long long)sh->sector, dd_idx1, dd_idx2, |
1808 | faila, failb); | |
16a53ecc | 1809 | |
67cc2b81 | 1810 | if (failb == syndrome_disks+1) { |
16a53ecc | 1811 | /* Q disk is one of the missing disks */ |
67cc2b81 | 1812 | if (faila == syndrome_disks) { |
16a53ecc N |
1813 | /* Missing P+Q, just recompute */ |
1814 | compute_parity6(sh, UPDATE_PARITY); | |
1815 | return; | |
1816 | } else { | |
1817 | /* We're missing D+Q; recompute D from P */ | |
d0dabf7e N |
1818 | compute_block_1(sh, ((dd_idx1 == sh->qd_idx) ? |
1819 | dd_idx2 : dd_idx1), | |
1820 | 0); | |
16a53ecc N |
1821 | compute_parity6(sh, UPDATE_PARITY); /* Is this necessary? */ |
1822 | return; | |
1823 | } | |
1824 | } | |
1825 | ||
d0dabf7e | 1826 | /* We're missing D+P or D+D; */ |
67cc2b81 | 1827 | if (failb == syndrome_disks) { |
d0dabf7e | 1828 | /* We're missing D+P. */ |
67cc2b81 | 1829 | raid6_datap_recov(syndrome_disks+2, STRIPE_SIZE, faila, ptrs); |
d0dabf7e N |
1830 | } else { |
1831 | /* We're missing D+D. */ | |
67cc2b81 N |
1832 | raid6_2data_recov(syndrome_disks+2, STRIPE_SIZE, faila, failb, |
1833 | ptrs); | |
16a53ecc | 1834 | } |
d0dabf7e N |
1835 | |
1836 | /* Both the above update both missing blocks */ | |
1837 | set_bit(R5_UPTODATE, &sh->dev[dd_idx1].flags); | |
1838 | set_bit(R5_UPTODATE, &sh->dev[dd_idx2].flags); | |
16a53ecc N |
1839 | } |
1840 | ||
600aa109 | 1841 | static void |
1fe797e6 | 1842 | schedule_reconstruction5(struct stripe_head *sh, struct stripe_head_state *s, |
600aa109 | 1843 | int rcw, int expand) |
e33129d8 DW |
1844 | { |
1845 | int i, pd_idx = sh->pd_idx, disks = sh->disks; | |
e33129d8 DW |
1846 | |
1847 | if (rcw) { | |
1848 | /* if we are not expanding this is a proper write request, and | |
1849 | * there will be bios with new data to be drained into the | |
1850 | * stripe cache | |
1851 | */ | |
1852 | if (!expand) { | |
600aa109 DW |
1853 | sh->reconstruct_state = reconstruct_state_drain_run; |
1854 | set_bit(STRIPE_OP_BIODRAIN, &s->ops_request); | |
1855 | } else | |
1856 | sh->reconstruct_state = reconstruct_state_run; | |
16a53ecc | 1857 | |
600aa109 | 1858 | set_bit(STRIPE_OP_POSTXOR, &s->ops_request); |
e33129d8 DW |
1859 | |
1860 | for (i = disks; i--; ) { | |
1861 | struct r5dev *dev = &sh->dev[i]; | |
1862 | ||
1863 | if (dev->towrite) { | |
1864 | set_bit(R5_LOCKED, &dev->flags); | |
d8ee0728 | 1865 | set_bit(R5_Wantdrain, &dev->flags); |
e33129d8 DW |
1866 | if (!expand) |
1867 | clear_bit(R5_UPTODATE, &dev->flags); | |
600aa109 | 1868 | s->locked++; |
e33129d8 DW |
1869 | } |
1870 | } | |
600aa109 | 1871 | if (s->locked + 1 == disks) |
8b3e6cdc DW |
1872 | if (!test_and_set_bit(STRIPE_FULL_WRITE, &sh->state)) |
1873 | atomic_inc(&sh->raid_conf->pending_full_writes); | |
e33129d8 DW |
1874 | } else { |
1875 | BUG_ON(!(test_bit(R5_UPTODATE, &sh->dev[pd_idx].flags) || | |
1876 | test_bit(R5_Wantcompute, &sh->dev[pd_idx].flags))); | |
1877 | ||
d8ee0728 | 1878 | sh->reconstruct_state = reconstruct_state_prexor_drain_run; |
600aa109 DW |
1879 | set_bit(STRIPE_OP_PREXOR, &s->ops_request); |
1880 | set_bit(STRIPE_OP_BIODRAIN, &s->ops_request); | |
1881 | set_bit(STRIPE_OP_POSTXOR, &s->ops_request); | |
e33129d8 DW |
1882 | |
1883 | for (i = disks; i--; ) { | |
1884 | struct r5dev *dev = &sh->dev[i]; | |
1885 | if (i == pd_idx) | |
1886 | continue; | |
1887 | ||
e33129d8 DW |
1888 | if (dev->towrite && |
1889 | (test_bit(R5_UPTODATE, &dev->flags) || | |
d8ee0728 DW |
1890 | test_bit(R5_Wantcompute, &dev->flags))) { |
1891 | set_bit(R5_Wantdrain, &dev->flags); | |
e33129d8 DW |
1892 | set_bit(R5_LOCKED, &dev->flags); |
1893 | clear_bit(R5_UPTODATE, &dev->flags); | |
600aa109 | 1894 | s->locked++; |
e33129d8 DW |
1895 | } |
1896 | } | |
1897 | } | |
1898 | ||
1899 | /* keep the parity disk locked while asynchronous operations | |
1900 | * are in flight | |
1901 | */ | |
1902 | set_bit(R5_LOCKED, &sh->dev[pd_idx].flags); | |
1903 | clear_bit(R5_UPTODATE, &sh->dev[pd_idx].flags); | |
600aa109 | 1904 | s->locked++; |
e33129d8 | 1905 | |
600aa109 | 1906 | pr_debug("%s: stripe %llu locked: %d ops_request: %lx\n", |
e46b272b | 1907 | __func__, (unsigned long long)sh->sector, |
600aa109 | 1908 | s->locked, s->ops_request); |
e33129d8 | 1909 | } |
16a53ecc | 1910 | |
1da177e4 LT |
1911 | /* |
1912 | * Each stripe/dev can have one or more bion attached. | |
16a53ecc | 1913 | * toread/towrite point to the first in a chain. |
1da177e4 LT |
1914 | * The bi_next chain must be in order. |
1915 | */ | |
1916 | static int add_stripe_bio(struct stripe_head *sh, struct bio *bi, int dd_idx, int forwrite) | |
1917 | { | |
1918 | struct bio **bip; | |
1919 | raid5_conf_t *conf = sh->raid_conf; | |
72626685 | 1920 | int firstwrite=0; |
1da177e4 | 1921 | |
45b4233c | 1922 | pr_debug("adding bh b#%llu to stripe s#%llu\n", |
1da177e4 LT |
1923 | (unsigned long long)bi->bi_sector, |
1924 | (unsigned long long)sh->sector); | |
1925 | ||
1926 | ||
1927 | spin_lock(&sh->lock); | |
1928 | spin_lock_irq(&conf->device_lock); | |
72626685 | 1929 | if (forwrite) { |
1da177e4 | 1930 | bip = &sh->dev[dd_idx].towrite; |
72626685 N |
1931 | if (*bip == NULL && sh->dev[dd_idx].written == NULL) |
1932 | firstwrite = 1; | |
1933 | } else | |
1da177e4 LT |
1934 | bip = &sh->dev[dd_idx].toread; |
1935 | while (*bip && (*bip)->bi_sector < bi->bi_sector) { | |
1936 | if ((*bip)->bi_sector + ((*bip)->bi_size >> 9) > bi->bi_sector) | |
1937 | goto overlap; | |
1938 | bip = & (*bip)->bi_next; | |
1939 | } | |
1940 | if (*bip && (*bip)->bi_sector < bi->bi_sector + ((bi->bi_size)>>9)) | |
1941 | goto overlap; | |
1942 | ||
78bafebd | 1943 | BUG_ON(*bip && bi->bi_next && (*bip) != bi->bi_next); |
1da177e4 LT |
1944 | if (*bip) |
1945 | bi->bi_next = *bip; | |
1946 | *bip = bi; | |
960e739d | 1947 | bi->bi_phys_segments++; |
1da177e4 LT |
1948 | spin_unlock_irq(&conf->device_lock); |
1949 | spin_unlock(&sh->lock); | |
1950 | ||
45b4233c | 1951 | pr_debug("added bi b#%llu to stripe s#%llu, disk %d.\n", |
1da177e4 LT |
1952 | (unsigned long long)bi->bi_sector, |
1953 | (unsigned long long)sh->sector, dd_idx); | |
1954 | ||
72626685 | 1955 | if (conf->mddev->bitmap && firstwrite) { |
72626685 N |
1956 | bitmap_startwrite(conf->mddev->bitmap, sh->sector, |
1957 | STRIPE_SECTORS, 0); | |
ae3c20cc | 1958 | sh->bm_seq = conf->seq_flush+1; |
72626685 N |
1959 | set_bit(STRIPE_BIT_DELAY, &sh->state); |
1960 | } | |
1961 | ||
1da177e4 LT |
1962 | if (forwrite) { |
1963 | /* check if page is covered */ | |
1964 | sector_t sector = sh->dev[dd_idx].sector; | |
1965 | for (bi=sh->dev[dd_idx].towrite; | |
1966 | sector < sh->dev[dd_idx].sector + STRIPE_SECTORS && | |
1967 | bi && bi->bi_sector <= sector; | |
1968 | bi = r5_next_bio(bi, sh->dev[dd_idx].sector)) { | |
1969 | if (bi->bi_sector + (bi->bi_size>>9) >= sector) | |
1970 | sector = bi->bi_sector + (bi->bi_size>>9); | |
1971 | } | |
1972 | if (sector >= sh->dev[dd_idx].sector + STRIPE_SECTORS) | |
1973 | set_bit(R5_OVERWRITE, &sh->dev[dd_idx].flags); | |
1974 | } | |
1975 | return 1; | |
1976 | ||
1977 | overlap: | |
1978 | set_bit(R5_Overlap, &sh->dev[dd_idx].flags); | |
1979 | spin_unlock_irq(&conf->device_lock); | |
1980 | spin_unlock(&sh->lock); | |
1981 | return 0; | |
1982 | } | |
1983 | ||
29269553 N |
1984 | static void end_reshape(raid5_conf_t *conf); |
1985 | ||
16a53ecc N |
1986 | static int page_is_zero(struct page *p) |
1987 | { | |
1988 | char *a = page_address(p); | |
1989 | return ((*(u32*)a) == 0 && | |
1990 | memcmp(a, a+4, STRIPE_SIZE-4)==0); | |
1991 | } | |
1992 | ||
911d4ee8 N |
1993 | static void stripe_set_idx(sector_t stripe, raid5_conf_t *conf, int previous, |
1994 | struct stripe_head *sh) | |
ccfcc3c1 | 1995 | { |
784052ec N |
1996 | int sectors_per_chunk = |
1997 | previous ? (conf->prev_chunk >> 9) | |
1998 | : (conf->chunk_size >> 9); | |
911d4ee8 | 1999 | int dd_idx; |
2d2063ce | 2000 | int chunk_offset = sector_div(stripe, sectors_per_chunk); |
112bf897 | 2001 | int disks = previous ? conf->previous_raid_disks : conf->raid_disks; |
2d2063ce | 2002 | |
112bf897 N |
2003 | raid5_compute_sector(conf, |
2004 | stripe * (disks - conf->max_degraded) | |
b875e531 | 2005 | *sectors_per_chunk + chunk_offset, |
112bf897 | 2006 | previous, |
911d4ee8 | 2007 | &dd_idx, sh); |
ccfcc3c1 N |
2008 | } |
2009 | ||
a4456856 | 2010 | static void |
1fe797e6 | 2011 | handle_failed_stripe(raid5_conf_t *conf, struct stripe_head *sh, |
a4456856 DW |
2012 | struct stripe_head_state *s, int disks, |
2013 | struct bio **return_bi) | |
2014 | { | |
2015 | int i; | |
2016 | for (i = disks; i--; ) { | |
2017 | struct bio *bi; | |
2018 | int bitmap_end = 0; | |
2019 | ||
2020 | if (test_bit(R5_ReadError, &sh->dev[i].flags)) { | |
2021 | mdk_rdev_t *rdev; | |
2022 | rcu_read_lock(); | |
2023 | rdev = rcu_dereference(conf->disks[i].rdev); | |
2024 | if (rdev && test_bit(In_sync, &rdev->flags)) | |
2025 | /* multiple read failures in one stripe */ | |
2026 | md_error(conf->mddev, rdev); | |
2027 | rcu_read_unlock(); | |
2028 | } | |
2029 | spin_lock_irq(&conf->device_lock); | |
2030 | /* fail all writes first */ | |
2031 | bi = sh->dev[i].towrite; | |
2032 | sh->dev[i].towrite = NULL; | |
2033 | if (bi) { | |
2034 | s->to_write--; | |
2035 | bitmap_end = 1; | |
2036 | } | |
2037 | ||
2038 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) | |
2039 | wake_up(&conf->wait_for_overlap); | |
2040 | ||
2041 | while (bi && bi->bi_sector < | |
2042 | sh->dev[i].sector + STRIPE_SECTORS) { | |
2043 | struct bio *nextbi = r5_next_bio(bi, sh->dev[i].sector); | |
2044 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
960e739d | 2045 | if (!raid5_dec_bi_phys_segments(bi)) { |
a4456856 DW |
2046 | md_write_end(conf->mddev); |
2047 | bi->bi_next = *return_bi; | |
2048 | *return_bi = bi; | |
2049 | } | |
2050 | bi = nextbi; | |
2051 | } | |
2052 | /* and fail all 'written' */ | |
2053 | bi = sh->dev[i].written; | |
2054 | sh->dev[i].written = NULL; | |
2055 | if (bi) bitmap_end = 1; | |
2056 | while (bi && bi->bi_sector < | |
2057 | sh->dev[i].sector + STRIPE_SECTORS) { | |
2058 | struct bio *bi2 = r5_next_bio(bi, sh->dev[i].sector); | |
2059 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
960e739d | 2060 | if (!raid5_dec_bi_phys_segments(bi)) { |
a4456856 DW |
2061 | md_write_end(conf->mddev); |
2062 | bi->bi_next = *return_bi; | |
2063 | *return_bi = bi; | |
2064 | } | |
2065 | bi = bi2; | |
2066 | } | |
2067 | ||
b5e98d65 DW |
2068 | /* fail any reads if this device is non-operational and |
2069 | * the data has not reached the cache yet. | |
2070 | */ | |
2071 | if (!test_bit(R5_Wantfill, &sh->dev[i].flags) && | |
2072 | (!test_bit(R5_Insync, &sh->dev[i].flags) || | |
2073 | test_bit(R5_ReadError, &sh->dev[i].flags))) { | |
a4456856 DW |
2074 | bi = sh->dev[i].toread; |
2075 | sh->dev[i].toread = NULL; | |
2076 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) | |
2077 | wake_up(&conf->wait_for_overlap); | |
2078 | if (bi) s->to_read--; | |
2079 | while (bi && bi->bi_sector < | |
2080 | sh->dev[i].sector + STRIPE_SECTORS) { | |
2081 | struct bio *nextbi = | |
2082 | r5_next_bio(bi, sh->dev[i].sector); | |
2083 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
960e739d | 2084 | if (!raid5_dec_bi_phys_segments(bi)) { |
a4456856 DW |
2085 | bi->bi_next = *return_bi; |
2086 | *return_bi = bi; | |
2087 | } | |
2088 | bi = nextbi; | |
2089 | } | |
2090 | } | |
2091 | spin_unlock_irq(&conf->device_lock); | |
2092 | if (bitmap_end) | |
2093 | bitmap_endwrite(conf->mddev->bitmap, sh->sector, | |
2094 | STRIPE_SECTORS, 0, 0); | |
2095 | } | |
2096 | ||
8b3e6cdc DW |
2097 | if (test_and_clear_bit(STRIPE_FULL_WRITE, &sh->state)) |
2098 | if (atomic_dec_and_test(&conf->pending_full_writes)) | |
2099 | md_wakeup_thread(conf->mddev->thread); | |
a4456856 DW |
2100 | } |
2101 | ||
1fe797e6 DW |
2102 | /* fetch_block5 - checks the given member device to see if its data needs |
2103 | * to be read or computed to satisfy a request. | |
2104 | * | |
2105 | * Returns 1 when no more member devices need to be checked, otherwise returns | |
2106 | * 0 to tell the loop in handle_stripe_fill5 to continue | |
f38e1219 | 2107 | */ |
1fe797e6 DW |
2108 | static int fetch_block5(struct stripe_head *sh, struct stripe_head_state *s, |
2109 | int disk_idx, int disks) | |
f38e1219 DW |
2110 | { |
2111 | struct r5dev *dev = &sh->dev[disk_idx]; | |
2112 | struct r5dev *failed_dev = &sh->dev[s->failed_num]; | |
2113 | ||
f38e1219 DW |
2114 | /* is the data in this block needed, and can we get it? */ |
2115 | if (!test_bit(R5_LOCKED, &dev->flags) && | |
1fe797e6 DW |
2116 | !test_bit(R5_UPTODATE, &dev->flags) && |
2117 | (dev->toread || | |
2118 | (dev->towrite && !test_bit(R5_OVERWRITE, &dev->flags)) || | |
2119 | s->syncing || s->expanding || | |
2120 | (s->failed && | |
2121 | (failed_dev->toread || | |
2122 | (failed_dev->towrite && | |
2123 | !test_bit(R5_OVERWRITE, &failed_dev->flags)))))) { | |
976ea8d4 DW |
2124 | /* We would like to get this block, possibly by computing it, |
2125 | * otherwise read it if the backing disk is insync | |
f38e1219 DW |
2126 | */ |
2127 | if ((s->uptodate == disks - 1) && | |
ecc65c9b | 2128 | (s->failed && disk_idx == s->failed_num)) { |
976ea8d4 DW |
2129 | set_bit(STRIPE_COMPUTE_RUN, &sh->state); |
2130 | set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request); | |
f38e1219 DW |
2131 | set_bit(R5_Wantcompute, &dev->flags); |
2132 | sh->ops.target = disk_idx; | |
2133 | s->req_compute = 1; | |
f38e1219 DW |
2134 | /* Careful: from this point on 'uptodate' is in the eye |
2135 | * of raid5_run_ops which services 'compute' operations | |
2136 | * before writes. R5_Wantcompute flags a block that will | |
2137 | * be R5_UPTODATE by the time it is needed for a | |
2138 | * subsequent operation. | |
2139 | */ | |
2140 | s->uptodate++; | |
1fe797e6 | 2141 | return 1; /* uptodate + compute == disks */ |
7a1fc53c | 2142 | } else if (test_bit(R5_Insync, &dev->flags)) { |
f38e1219 DW |
2143 | set_bit(R5_LOCKED, &dev->flags); |
2144 | set_bit(R5_Wantread, &dev->flags); | |
f38e1219 DW |
2145 | s->locked++; |
2146 | pr_debug("Reading block %d (sync=%d)\n", disk_idx, | |
2147 | s->syncing); | |
2148 | } | |
2149 | } | |
2150 | ||
1fe797e6 | 2151 | return 0; |
f38e1219 DW |
2152 | } |
2153 | ||
1fe797e6 DW |
2154 | /** |
2155 | * handle_stripe_fill5 - read or compute data to satisfy pending requests. | |
2156 | */ | |
2157 | static void handle_stripe_fill5(struct stripe_head *sh, | |
a4456856 DW |
2158 | struct stripe_head_state *s, int disks) |
2159 | { | |
2160 | int i; | |
f38e1219 | 2161 | |
f38e1219 DW |
2162 | /* look for blocks to read/compute, skip this if a compute |
2163 | * is already in flight, or if the stripe contents are in the | |
2164 | * midst of changing due to a write | |
2165 | */ | |
976ea8d4 | 2166 | if (!test_bit(STRIPE_COMPUTE_RUN, &sh->state) && !sh->check_state && |
1fe797e6 | 2167 | !sh->reconstruct_state) |
f38e1219 | 2168 | for (i = disks; i--; ) |
1fe797e6 | 2169 | if (fetch_block5(sh, s, i, disks)) |
f38e1219 | 2170 | break; |
a4456856 DW |
2171 | set_bit(STRIPE_HANDLE, &sh->state); |
2172 | } | |
2173 | ||
1fe797e6 | 2174 | static void handle_stripe_fill6(struct stripe_head *sh, |
a4456856 DW |
2175 | struct stripe_head_state *s, struct r6_state *r6s, |
2176 | int disks) | |
2177 | { | |
2178 | int i; | |
2179 | for (i = disks; i--; ) { | |
2180 | struct r5dev *dev = &sh->dev[i]; | |
2181 | if (!test_bit(R5_LOCKED, &dev->flags) && | |
2182 | !test_bit(R5_UPTODATE, &dev->flags) && | |
2183 | (dev->toread || (dev->towrite && | |
2184 | !test_bit(R5_OVERWRITE, &dev->flags)) || | |
2185 | s->syncing || s->expanding || | |
2186 | (s->failed >= 1 && | |
2187 | (sh->dev[r6s->failed_num[0]].toread || | |
2188 | s->to_write)) || | |
2189 | (s->failed >= 2 && | |
2190 | (sh->dev[r6s->failed_num[1]].toread || | |
2191 | s->to_write)))) { | |
2192 | /* we would like to get this block, possibly | |
2193 | * by computing it, but we might not be able to | |
2194 | */ | |
c337869d DW |
2195 | if ((s->uptodate == disks - 1) && |
2196 | (s->failed && (i == r6s->failed_num[0] || | |
2197 | i == r6s->failed_num[1]))) { | |
45b4233c | 2198 | pr_debug("Computing stripe %llu block %d\n", |
a4456856 DW |
2199 | (unsigned long long)sh->sector, i); |
2200 | compute_block_1(sh, i, 0); | |
2201 | s->uptodate++; | |
2202 | } else if ( s->uptodate == disks-2 && s->failed >= 2 ) { | |
2203 | /* Computing 2-failure is *very* expensive; only | |
2204 | * do it if failed >= 2 | |
2205 | */ | |
2206 | int other; | |
2207 | for (other = disks; other--; ) { | |
2208 | if (other == i) | |
2209 | continue; | |
2210 | if (!test_bit(R5_UPTODATE, | |
2211 | &sh->dev[other].flags)) | |
2212 | break; | |
2213 | } | |
2214 | BUG_ON(other < 0); | |
45b4233c | 2215 | pr_debug("Computing stripe %llu blocks %d,%d\n", |
a4456856 DW |
2216 | (unsigned long long)sh->sector, |
2217 | i, other); | |
2218 | compute_block_2(sh, i, other); | |
2219 | s->uptodate += 2; | |
2220 | } else if (test_bit(R5_Insync, &dev->flags)) { | |
2221 | set_bit(R5_LOCKED, &dev->flags); | |
2222 | set_bit(R5_Wantread, &dev->flags); | |
2223 | s->locked++; | |
45b4233c | 2224 | pr_debug("Reading block %d (sync=%d)\n", |
a4456856 DW |
2225 | i, s->syncing); |
2226 | } | |
2227 | } | |
2228 | } | |
2229 | set_bit(STRIPE_HANDLE, &sh->state); | |
2230 | } | |
2231 | ||
2232 | ||
1fe797e6 | 2233 | /* handle_stripe_clean_event |
a4456856 DW |
2234 | * any written block on an uptodate or failed drive can be returned. |
2235 | * Note that if we 'wrote' to a failed drive, it will be UPTODATE, but | |
2236 | * never LOCKED, so we don't need to test 'failed' directly. | |
2237 | */ | |
1fe797e6 | 2238 | static void handle_stripe_clean_event(raid5_conf_t *conf, |
a4456856 DW |
2239 | struct stripe_head *sh, int disks, struct bio **return_bi) |
2240 | { | |
2241 | int i; | |
2242 | struct r5dev *dev; | |
2243 | ||
2244 | for (i = disks; i--; ) | |
2245 | if (sh->dev[i].written) { | |
2246 | dev = &sh->dev[i]; | |
2247 | if (!test_bit(R5_LOCKED, &dev->flags) && | |
2248 | test_bit(R5_UPTODATE, &dev->flags)) { | |
2249 | /* We can return any write requests */ | |
2250 | struct bio *wbi, *wbi2; | |
2251 | int bitmap_end = 0; | |
45b4233c | 2252 | pr_debug("Return write for disc %d\n", i); |
a4456856 DW |
2253 | spin_lock_irq(&conf->device_lock); |
2254 | wbi = dev->written; | |
2255 | dev->written = NULL; | |
2256 | while (wbi && wbi->bi_sector < | |
2257 | dev->sector + STRIPE_SECTORS) { | |
2258 | wbi2 = r5_next_bio(wbi, dev->sector); | |
960e739d | 2259 | if (!raid5_dec_bi_phys_segments(wbi)) { |
a4456856 DW |
2260 | md_write_end(conf->mddev); |
2261 | wbi->bi_next = *return_bi; | |
2262 | *return_bi = wbi; | |
2263 | } | |
2264 | wbi = wbi2; | |
2265 | } | |
2266 | if (dev->towrite == NULL) | |
2267 | bitmap_end = 1; | |
2268 | spin_unlock_irq(&conf->device_lock); | |
2269 | if (bitmap_end) | |
2270 | bitmap_endwrite(conf->mddev->bitmap, | |
2271 | sh->sector, | |
2272 | STRIPE_SECTORS, | |
2273 | !test_bit(STRIPE_DEGRADED, &sh->state), | |
2274 | 0); | |
2275 | } | |
2276 | } | |
8b3e6cdc DW |
2277 | |
2278 | if (test_and_clear_bit(STRIPE_FULL_WRITE, &sh->state)) | |
2279 | if (atomic_dec_and_test(&conf->pending_full_writes)) | |
2280 | md_wakeup_thread(conf->mddev->thread); | |
a4456856 DW |
2281 | } |
2282 | ||
1fe797e6 | 2283 | static void handle_stripe_dirtying5(raid5_conf_t *conf, |
a4456856 DW |
2284 | struct stripe_head *sh, struct stripe_head_state *s, int disks) |
2285 | { | |
2286 | int rmw = 0, rcw = 0, i; | |
2287 | for (i = disks; i--; ) { | |
2288 | /* would I have to read this buffer for read_modify_write */ | |
2289 | struct r5dev *dev = &sh->dev[i]; | |
2290 | if ((dev->towrite || i == sh->pd_idx) && | |
2291 | !test_bit(R5_LOCKED, &dev->flags) && | |
f38e1219 DW |
2292 | !(test_bit(R5_UPTODATE, &dev->flags) || |
2293 | test_bit(R5_Wantcompute, &dev->flags))) { | |
a4456856 DW |
2294 | if (test_bit(R5_Insync, &dev->flags)) |
2295 | rmw++; | |
2296 | else | |
2297 | rmw += 2*disks; /* cannot read it */ | |
2298 | } | |
2299 | /* Would I have to read this buffer for reconstruct_write */ | |
2300 | if (!test_bit(R5_OVERWRITE, &dev->flags) && i != sh->pd_idx && | |
2301 | !test_bit(R5_LOCKED, &dev->flags) && | |
f38e1219 DW |
2302 | !(test_bit(R5_UPTODATE, &dev->flags) || |
2303 | test_bit(R5_Wantcompute, &dev->flags))) { | |
2304 | if (test_bit(R5_Insync, &dev->flags)) rcw++; | |
a4456856 DW |
2305 | else |
2306 | rcw += 2*disks; | |
2307 | } | |
2308 | } | |
45b4233c | 2309 | pr_debug("for sector %llu, rmw=%d rcw=%d\n", |
a4456856 DW |
2310 | (unsigned long long)sh->sector, rmw, rcw); |
2311 | set_bit(STRIPE_HANDLE, &sh->state); | |
2312 | if (rmw < rcw && rmw > 0) | |
2313 | /* prefer read-modify-write, but need to get some data */ | |
2314 | for (i = disks; i--; ) { | |
2315 | struct r5dev *dev = &sh->dev[i]; | |
2316 | if ((dev->towrite || i == sh->pd_idx) && | |
2317 | !test_bit(R5_LOCKED, &dev->flags) && | |
f38e1219 DW |
2318 | !(test_bit(R5_UPTODATE, &dev->flags) || |
2319 | test_bit(R5_Wantcompute, &dev->flags)) && | |
a4456856 DW |
2320 | test_bit(R5_Insync, &dev->flags)) { |
2321 | if ( | |
2322 | test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
45b4233c | 2323 | pr_debug("Read_old block " |
a4456856 DW |
2324 | "%d for r-m-w\n", i); |
2325 | set_bit(R5_LOCKED, &dev->flags); | |
2326 | set_bit(R5_Wantread, &dev->flags); | |
2327 | s->locked++; | |
2328 | } else { | |
2329 | set_bit(STRIPE_DELAYED, &sh->state); | |
2330 | set_bit(STRIPE_HANDLE, &sh->state); | |
2331 | } | |
2332 | } | |
2333 | } | |
2334 | if (rcw <= rmw && rcw > 0) | |
2335 | /* want reconstruct write, but need to get some data */ | |
2336 | for (i = disks; i--; ) { | |
2337 | struct r5dev *dev = &sh->dev[i]; | |
2338 | if (!test_bit(R5_OVERWRITE, &dev->flags) && | |
2339 | i != sh->pd_idx && | |
2340 | !test_bit(R5_LOCKED, &dev->flags) && | |
f38e1219 DW |
2341 | !(test_bit(R5_UPTODATE, &dev->flags) || |
2342 | test_bit(R5_Wantcompute, &dev->flags)) && | |
a4456856 DW |
2343 | test_bit(R5_Insync, &dev->flags)) { |
2344 | if ( | |
2345 | test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
45b4233c | 2346 | pr_debug("Read_old block " |
a4456856 DW |
2347 | "%d for Reconstruct\n", i); |
2348 | set_bit(R5_LOCKED, &dev->flags); | |
2349 | set_bit(R5_Wantread, &dev->flags); | |
2350 | s->locked++; | |
2351 | } else { | |
2352 | set_bit(STRIPE_DELAYED, &sh->state); | |
2353 | set_bit(STRIPE_HANDLE, &sh->state); | |
2354 | } | |
2355 | } | |
2356 | } | |
2357 | /* now if nothing is locked, and if we have enough data, | |
2358 | * we can start a write request | |
2359 | */ | |
f38e1219 DW |
2360 | /* since handle_stripe can be called at any time we need to handle the |
2361 | * case where a compute block operation has been submitted and then a | |
2362 | * subsequent call wants to start a write request. raid5_run_ops only | |
2363 | * handles the case where compute block and postxor are requested | |
2364 | * simultaneously. If this is not the case then new writes need to be | |
2365 | * held off until the compute completes. | |
2366 | */ | |
976ea8d4 DW |
2367 | if ((s->req_compute || !test_bit(STRIPE_COMPUTE_RUN, &sh->state)) && |
2368 | (s->locked == 0 && (rcw == 0 || rmw == 0) && | |
2369 | !test_bit(STRIPE_BIT_DELAY, &sh->state))) | |
1fe797e6 | 2370 | schedule_reconstruction5(sh, s, rcw == 0, 0); |
a4456856 DW |
2371 | } |
2372 | ||
1fe797e6 | 2373 | static void handle_stripe_dirtying6(raid5_conf_t *conf, |
a4456856 DW |
2374 | struct stripe_head *sh, struct stripe_head_state *s, |
2375 | struct r6_state *r6s, int disks) | |
2376 | { | |
2377 | int rcw = 0, must_compute = 0, pd_idx = sh->pd_idx, i; | |
34e04e87 | 2378 | int qd_idx = sh->qd_idx; |
a4456856 DW |
2379 | for (i = disks; i--; ) { |
2380 | struct r5dev *dev = &sh->dev[i]; | |
2381 | /* Would I have to read this buffer for reconstruct_write */ | |
2382 | if (!test_bit(R5_OVERWRITE, &dev->flags) | |
2383 | && i != pd_idx && i != qd_idx | |
2384 | && (!test_bit(R5_LOCKED, &dev->flags) | |
2385 | ) && | |
2386 | !test_bit(R5_UPTODATE, &dev->flags)) { | |
2387 | if (test_bit(R5_Insync, &dev->flags)) rcw++; | |
2388 | else { | |
45b4233c | 2389 | pr_debug("raid6: must_compute: " |
a4456856 DW |
2390 | "disk %d flags=%#lx\n", i, dev->flags); |
2391 | must_compute++; | |
2392 | } | |
2393 | } | |
2394 | } | |
45b4233c | 2395 | pr_debug("for sector %llu, rcw=%d, must_compute=%d\n", |
a4456856 DW |
2396 | (unsigned long long)sh->sector, rcw, must_compute); |
2397 | set_bit(STRIPE_HANDLE, &sh->state); | |
2398 | ||
2399 | if (rcw > 0) | |
2400 | /* want reconstruct write, but need to get some data */ | |
2401 | for (i = disks; i--; ) { | |
2402 | struct r5dev *dev = &sh->dev[i]; | |
2403 | if (!test_bit(R5_OVERWRITE, &dev->flags) | |
2404 | && !(s->failed == 0 && (i == pd_idx || i == qd_idx)) | |
2405 | && !test_bit(R5_LOCKED, &dev->flags) && | |
2406 | !test_bit(R5_UPTODATE, &dev->flags) && | |
2407 | test_bit(R5_Insync, &dev->flags)) { | |
2408 | if ( | |
2409 | test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
45b4233c | 2410 | pr_debug("Read_old stripe %llu " |
a4456856 DW |
2411 | "block %d for Reconstruct\n", |
2412 | (unsigned long long)sh->sector, i); | |
2413 | set_bit(R5_LOCKED, &dev->flags); | |
2414 | set_bit(R5_Wantread, &dev->flags); | |
2415 | s->locked++; | |
2416 | } else { | |
45b4233c | 2417 | pr_debug("Request delayed stripe %llu " |
a4456856 DW |
2418 | "block %d for Reconstruct\n", |
2419 | (unsigned long long)sh->sector, i); | |
2420 | set_bit(STRIPE_DELAYED, &sh->state); | |
2421 | set_bit(STRIPE_HANDLE, &sh->state); | |
2422 | } | |
2423 | } | |
2424 | } | |
2425 | /* now if nothing is locked, and if we have enough data, we can start a | |
2426 | * write request | |
2427 | */ | |
2428 | if (s->locked == 0 && rcw == 0 && | |
2429 | !test_bit(STRIPE_BIT_DELAY, &sh->state)) { | |
2430 | if (must_compute > 0) { | |
2431 | /* We have failed blocks and need to compute them */ | |
2432 | switch (s->failed) { | |
2433 | case 0: | |
2434 | BUG(); | |
2435 | case 1: | |
2436 | compute_block_1(sh, r6s->failed_num[0], 0); | |
2437 | break; | |
2438 | case 2: | |
2439 | compute_block_2(sh, r6s->failed_num[0], | |
2440 | r6s->failed_num[1]); | |
2441 | break; | |
2442 | default: /* This request should have been failed? */ | |
2443 | BUG(); | |
2444 | } | |
2445 | } | |
2446 | ||
45b4233c | 2447 | pr_debug("Computing parity for stripe %llu\n", |
a4456856 DW |
2448 | (unsigned long long)sh->sector); |
2449 | compute_parity6(sh, RECONSTRUCT_WRITE); | |
2450 | /* now every locked buffer is ready to be written */ | |
2451 | for (i = disks; i--; ) | |
2452 | if (test_bit(R5_LOCKED, &sh->dev[i].flags)) { | |
45b4233c | 2453 | pr_debug("Writing stripe %llu block %d\n", |
a4456856 DW |
2454 | (unsigned long long)sh->sector, i); |
2455 | s->locked++; | |
2456 | set_bit(R5_Wantwrite, &sh->dev[i].flags); | |
2457 | } | |
8b3e6cdc DW |
2458 | if (s->locked == disks) |
2459 | if (!test_and_set_bit(STRIPE_FULL_WRITE, &sh->state)) | |
2460 | atomic_inc(&conf->pending_full_writes); | |
a4456856 DW |
2461 | /* after a RECONSTRUCT_WRITE, the stripe MUST be in-sync */ |
2462 | set_bit(STRIPE_INSYNC, &sh->state); | |
2463 | ||
2464 | if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
2465 | atomic_dec(&conf->preread_active_stripes); | |
2466 | if (atomic_read(&conf->preread_active_stripes) < | |
2467 | IO_THRESHOLD) | |
2468 | md_wakeup_thread(conf->mddev->thread); | |
2469 | } | |
2470 | } | |
2471 | } | |
2472 | ||
2473 | static void handle_parity_checks5(raid5_conf_t *conf, struct stripe_head *sh, | |
2474 | struct stripe_head_state *s, int disks) | |
2475 | { | |
ecc65c9b | 2476 | struct r5dev *dev = NULL; |
bd2ab670 | 2477 | |
a4456856 | 2478 | set_bit(STRIPE_HANDLE, &sh->state); |
e89f8962 | 2479 | |
ecc65c9b DW |
2480 | switch (sh->check_state) { |
2481 | case check_state_idle: | |
2482 | /* start a new check operation if there are no failures */ | |
bd2ab670 | 2483 | if (s->failed == 0) { |
bd2ab670 | 2484 | BUG_ON(s->uptodate != disks); |
ecc65c9b DW |
2485 | sh->check_state = check_state_run; |
2486 | set_bit(STRIPE_OP_CHECK, &s->ops_request); | |
bd2ab670 | 2487 | clear_bit(R5_UPTODATE, &sh->dev[sh->pd_idx].flags); |
bd2ab670 | 2488 | s->uptodate--; |
ecc65c9b | 2489 | break; |
bd2ab670 | 2490 | } |
ecc65c9b DW |
2491 | dev = &sh->dev[s->failed_num]; |
2492 | /* fall through */ | |
2493 | case check_state_compute_result: | |
2494 | sh->check_state = check_state_idle; | |
2495 | if (!dev) | |
2496 | dev = &sh->dev[sh->pd_idx]; | |
2497 | ||
2498 | /* check that a write has not made the stripe insync */ | |
2499 | if (test_bit(STRIPE_INSYNC, &sh->state)) | |
2500 | break; | |
c8894419 | 2501 | |
a4456856 | 2502 | /* either failed parity check, or recovery is happening */ |
a4456856 DW |
2503 | BUG_ON(!test_bit(R5_UPTODATE, &dev->flags)); |
2504 | BUG_ON(s->uptodate != disks); | |
2505 | ||
2506 | set_bit(R5_LOCKED, &dev->flags); | |
ecc65c9b | 2507 | s->locked++; |
a4456856 | 2508 | set_bit(R5_Wantwrite, &dev->flags); |
830ea016 | 2509 | |
a4456856 | 2510 | clear_bit(STRIPE_DEGRADED, &sh->state); |
a4456856 | 2511 | set_bit(STRIPE_INSYNC, &sh->state); |
ecc65c9b DW |
2512 | break; |
2513 | case check_state_run: | |
2514 | break; /* we will be called again upon completion */ | |
2515 | case check_state_check_result: | |
2516 | sh->check_state = check_state_idle; | |
2517 | ||
2518 | /* if a failure occurred during the check operation, leave | |
2519 | * STRIPE_INSYNC not set and let the stripe be handled again | |
2520 | */ | |
2521 | if (s->failed) | |
2522 | break; | |
2523 | ||
2524 | /* handle a successful check operation, if parity is correct | |
2525 | * we are done. Otherwise update the mismatch count and repair | |
2526 | * parity if !MD_RECOVERY_CHECK | |
2527 | */ | |
2528 | if (sh->ops.zero_sum_result == 0) | |
2529 | /* parity is correct (on disc, | |
2530 | * not in buffer any more) | |
2531 | */ | |
2532 | set_bit(STRIPE_INSYNC, &sh->state); | |
2533 | else { | |
2534 | conf->mddev->resync_mismatches += STRIPE_SECTORS; | |
2535 | if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery)) | |
2536 | /* don't try to repair!! */ | |
2537 | set_bit(STRIPE_INSYNC, &sh->state); | |
2538 | else { | |
2539 | sh->check_state = check_state_compute_run; | |
976ea8d4 | 2540 | set_bit(STRIPE_COMPUTE_RUN, &sh->state); |
ecc65c9b DW |
2541 | set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request); |
2542 | set_bit(R5_Wantcompute, | |
2543 | &sh->dev[sh->pd_idx].flags); | |
2544 | sh->ops.target = sh->pd_idx; | |
2545 | s->uptodate++; | |
2546 | } | |
2547 | } | |
2548 | break; | |
2549 | case check_state_compute_run: | |
2550 | break; | |
2551 | default: | |
2552 | printk(KERN_ERR "%s: unknown check_state: %d sector: %llu\n", | |
2553 | __func__, sh->check_state, | |
2554 | (unsigned long long) sh->sector); | |
2555 | BUG(); | |
a4456856 DW |
2556 | } |
2557 | } | |
2558 | ||
2559 | ||
2560 | static void handle_parity_checks6(raid5_conf_t *conf, struct stripe_head *sh, | |
2561 | struct stripe_head_state *s, | |
2562 | struct r6_state *r6s, struct page *tmp_page, | |
2563 | int disks) | |
2564 | { | |
2565 | int update_p = 0, update_q = 0; | |
2566 | struct r5dev *dev; | |
2567 | int pd_idx = sh->pd_idx; | |
34e04e87 | 2568 | int qd_idx = sh->qd_idx; |
a4456856 DW |
2569 | |
2570 | set_bit(STRIPE_HANDLE, &sh->state); | |
2571 | ||
2572 | BUG_ON(s->failed > 2); | |
2573 | BUG_ON(s->uptodate < disks); | |
2574 | /* Want to check and possibly repair P and Q. | |
2575 | * However there could be one 'failed' device, in which | |
2576 | * case we can only check one of them, possibly using the | |
2577 | * other to generate missing data | |
2578 | */ | |
2579 | ||
2580 | /* If !tmp_page, we cannot do the calculations, | |
2581 | * but as we have set STRIPE_HANDLE, we will soon be called | |
2582 | * by stripe_handle with a tmp_page - just wait until then. | |
2583 | */ | |
2584 | if (tmp_page) { | |
2585 | if (s->failed == r6s->q_failed) { | |
2586 | /* The only possible failed device holds 'Q', so it | |
2587 | * makes sense to check P (If anything else were failed, | |
2588 | * we would have used P to recreate it). | |
2589 | */ | |
2590 | compute_block_1(sh, pd_idx, 1); | |
2591 | if (!page_is_zero(sh->dev[pd_idx].page)) { | |
2592 | compute_block_1(sh, pd_idx, 0); | |
2593 | update_p = 1; | |
2594 | } | |
2595 | } | |
2596 | if (!r6s->q_failed && s->failed < 2) { | |
2597 | /* q is not failed, and we didn't use it to generate | |
2598 | * anything, so it makes sense to check it | |
2599 | */ | |
2600 | memcpy(page_address(tmp_page), | |
2601 | page_address(sh->dev[qd_idx].page), | |
2602 | STRIPE_SIZE); | |
2603 | compute_parity6(sh, UPDATE_PARITY); | |
2604 | if (memcmp(page_address(tmp_page), | |
2605 | page_address(sh->dev[qd_idx].page), | |
2606 | STRIPE_SIZE) != 0) { | |
2607 | clear_bit(STRIPE_INSYNC, &sh->state); | |
2608 | update_q = 1; | |
2609 | } | |
2610 | } | |
2611 | if (update_p || update_q) { | |
2612 | conf->mddev->resync_mismatches += STRIPE_SECTORS; | |
2613 | if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery)) | |
2614 | /* don't try to repair!! */ | |
2615 | update_p = update_q = 0; | |
2616 | } | |
2617 | ||
2618 | /* now write out any block on a failed drive, | |
2619 | * or P or Q if they need it | |
2620 | */ | |
2621 | ||
2622 | if (s->failed == 2) { | |
2623 | dev = &sh->dev[r6s->failed_num[1]]; | |
2624 | s->locked++; | |
2625 | set_bit(R5_LOCKED, &dev->flags); | |
2626 | set_bit(R5_Wantwrite, &dev->flags); | |
2627 | } | |
2628 | if (s->failed >= 1) { | |
2629 | dev = &sh->dev[r6s->failed_num[0]]; | |
2630 | s->locked++; | |
2631 | set_bit(R5_LOCKED, &dev->flags); | |
2632 | set_bit(R5_Wantwrite, &dev->flags); | |
2633 | } | |
2634 | ||
2635 | if (update_p) { | |
2636 | dev = &sh->dev[pd_idx]; | |
2637 | s->locked++; | |
2638 | set_bit(R5_LOCKED, &dev->flags); | |
2639 | set_bit(R5_Wantwrite, &dev->flags); | |
2640 | } | |
2641 | if (update_q) { | |
2642 | dev = &sh->dev[qd_idx]; | |
2643 | s->locked++; | |
2644 | set_bit(R5_LOCKED, &dev->flags); | |
2645 | set_bit(R5_Wantwrite, &dev->flags); | |
2646 | } | |
2647 | clear_bit(STRIPE_DEGRADED, &sh->state); | |
2648 | ||
2649 | set_bit(STRIPE_INSYNC, &sh->state); | |
2650 | } | |
2651 | } | |
2652 | ||
2653 | static void handle_stripe_expansion(raid5_conf_t *conf, struct stripe_head *sh, | |
2654 | struct r6_state *r6s) | |
2655 | { | |
2656 | int i; | |
2657 | ||
2658 | /* We have read all the blocks in this stripe and now we need to | |
2659 | * copy some of them into a target stripe for expand. | |
2660 | */ | |
f0a50d37 | 2661 | struct dma_async_tx_descriptor *tx = NULL; |
a4456856 DW |
2662 | clear_bit(STRIPE_EXPAND_SOURCE, &sh->state); |
2663 | for (i = 0; i < sh->disks; i++) | |
34e04e87 | 2664 | if (i != sh->pd_idx && i != sh->qd_idx) { |
911d4ee8 | 2665 | int dd_idx, j; |
a4456856 DW |
2666 | struct stripe_head *sh2; |
2667 | ||
784052ec | 2668 | sector_t bn = compute_blocknr(sh, i, 1); |
911d4ee8 N |
2669 | sector_t s = raid5_compute_sector(conf, bn, 0, |
2670 | &dd_idx, NULL); | |
b5663ba4 | 2671 | sh2 = get_active_stripe(conf, s, 0, 1); |
a4456856 DW |
2672 | if (sh2 == NULL) |
2673 | /* so far only the early blocks of this stripe | |
2674 | * have been requested. When later blocks | |
2675 | * get requested, we will try again | |
2676 | */ | |
2677 | continue; | |
2678 | if (!test_bit(STRIPE_EXPANDING, &sh2->state) || | |
2679 | test_bit(R5_Expanded, &sh2->dev[dd_idx].flags)) { | |
2680 | /* must have already done this block */ | |
2681 | release_stripe(sh2); | |
2682 | continue; | |
2683 | } | |
f0a50d37 DW |
2684 | |
2685 | /* place all the copies on one channel */ | |
2686 | tx = async_memcpy(sh2->dev[dd_idx].page, | |
2687 | sh->dev[i].page, 0, 0, STRIPE_SIZE, | |
2688 | ASYNC_TX_DEP_ACK, tx, NULL, NULL); | |
2689 | ||
a4456856 DW |
2690 | set_bit(R5_Expanded, &sh2->dev[dd_idx].flags); |
2691 | set_bit(R5_UPTODATE, &sh2->dev[dd_idx].flags); | |
2692 | for (j = 0; j < conf->raid_disks; j++) | |
2693 | if (j != sh2->pd_idx && | |
d0dabf7e | 2694 | (!r6s || j != sh2->qd_idx) && |
a4456856 DW |
2695 | !test_bit(R5_Expanded, &sh2->dev[j].flags)) |
2696 | break; | |
2697 | if (j == conf->raid_disks) { | |
2698 | set_bit(STRIPE_EXPAND_READY, &sh2->state); | |
2699 | set_bit(STRIPE_HANDLE, &sh2->state); | |
2700 | } | |
2701 | release_stripe(sh2); | |
f0a50d37 | 2702 | |
a4456856 | 2703 | } |
a2e08551 N |
2704 | /* done submitting copies, wait for them to complete */ |
2705 | if (tx) { | |
2706 | async_tx_ack(tx); | |
2707 | dma_wait_for_async_tx(tx); | |
2708 | } | |
a4456856 | 2709 | } |
1da177e4 | 2710 | |
6bfe0b49 | 2711 | |
1da177e4 LT |
2712 | /* |
2713 | * handle_stripe - do things to a stripe. | |
2714 | * | |
2715 | * We lock the stripe and then examine the state of various bits | |
2716 | * to see what needs to be done. | |
2717 | * Possible results: | |
2718 | * return some read request which now have data | |
2719 | * return some write requests which are safely on disc | |
2720 | * schedule a read on some buffers | |
2721 | * schedule a write of some buffers | |
2722 | * return confirmation of parity correctness | |
2723 | * | |
1da177e4 LT |
2724 | * buffers are taken off read_list or write_list, and bh_cache buffers |
2725 | * get BH_Lock set before the stripe lock is released. | |
2726 | * | |
2727 | */ | |
a4456856 | 2728 | |
df10cfbc | 2729 | static bool handle_stripe5(struct stripe_head *sh) |
1da177e4 LT |
2730 | { |
2731 | raid5_conf_t *conf = sh->raid_conf; | |
a4456856 DW |
2732 | int disks = sh->disks, i; |
2733 | struct bio *return_bi = NULL; | |
2734 | struct stripe_head_state s; | |
1da177e4 | 2735 | struct r5dev *dev; |
6bfe0b49 | 2736 | mdk_rdev_t *blocked_rdev = NULL; |
e0a115e5 | 2737 | int prexor; |
1da177e4 | 2738 | |
a4456856 | 2739 | memset(&s, 0, sizeof(s)); |
600aa109 DW |
2740 | pr_debug("handling stripe %llu, state=%#lx cnt=%d, pd_idx=%d check:%d " |
2741 | "reconstruct:%d\n", (unsigned long long)sh->sector, sh->state, | |
2742 | atomic_read(&sh->count), sh->pd_idx, sh->check_state, | |
2743 | sh->reconstruct_state); | |
1da177e4 LT |
2744 | |
2745 | spin_lock(&sh->lock); | |
2746 | clear_bit(STRIPE_HANDLE, &sh->state); | |
2747 | clear_bit(STRIPE_DELAYED, &sh->state); | |
2748 | ||
a4456856 DW |
2749 | s.syncing = test_bit(STRIPE_SYNCING, &sh->state); |
2750 | s.expanding = test_bit(STRIPE_EXPAND_SOURCE, &sh->state); | |
2751 | s.expanded = test_bit(STRIPE_EXPAND_READY, &sh->state); | |
def6ae26 | 2752 | |
83de75cc | 2753 | /* Now to look around and see what can be done */ |
9910f16a | 2754 | rcu_read_lock(); |
1da177e4 LT |
2755 | for (i=disks; i--; ) { |
2756 | mdk_rdev_t *rdev; | |
a4456856 | 2757 | struct r5dev *dev = &sh->dev[i]; |
1da177e4 | 2758 | clear_bit(R5_Insync, &dev->flags); |
1da177e4 | 2759 | |
b5e98d65 DW |
2760 | pr_debug("check %d: state 0x%lx toread %p read %p write %p " |
2761 | "written %p\n", i, dev->flags, dev->toread, dev->read, | |
2762 | dev->towrite, dev->written); | |
2763 | ||
2764 | /* maybe we can request a biofill operation | |
2765 | * | |
2766 | * new wantfill requests are only permitted while | |
83de75cc | 2767 | * ops_complete_biofill is guaranteed to be inactive |
b5e98d65 DW |
2768 | */ |
2769 | if (test_bit(R5_UPTODATE, &dev->flags) && dev->toread && | |
83de75cc | 2770 | !test_bit(STRIPE_BIOFILL_RUN, &sh->state)) |
b5e98d65 | 2771 | set_bit(R5_Wantfill, &dev->flags); |
1da177e4 LT |
2772 | |
2773 | /* now count some things */ | |
a4456856 DW |
2774 | if (test_bit(R5_LOCKED, &dev->flags)) s.locked++; |
2775 | if (test_bit(R5_UPTODATE, &dev->flags)) s.uptodate++; | |
f38e1219 | 2776 | if (test_bit(R5_Wantcompute, &dev->flags)) s.compute++; |
1da177e4 | 2777 | |
b5e98d65 DW |
2778 | if (test_bit(R5_Wantfill, &dev->flags)) |
2779 | s.to_fill++; | |
2780 | else if (dev->toread) | |
a4456856 | 2781 | s.to_read++; |
1da177e4 | 2782 | if (dev->towrite) { |
a4456856 | 2783 | s.to_write++; |
1da177e4 | 2784 | if (!test_bit(R5_OVERWRITE, &dev->flags)) |
a4456856 | 2785 | s.non_overwrite++; |
1da177e4 | 2786 | } |
a4456856 DW |
2787 | if (dev->written) |
2788 | s.written++; | |
9910f16a | 2789 | rdev = rcu_dereference(conf->disks[i].rdev); |
ac4090d2 N |
2790 | if (blocked_rdev == NULL && |
2791 | rdev && unlikely(test_bit(Blocked, &rdev->flags))) { | |
6bfe0b49 DW |
2792 | blocked_rdev = rdev; |
2793 | atomic_inc(&rdev->nr_pending); | |
6bfe0b49 | 2794 | } |
b2d444d7 | 2795 | if (!rdev || !test_bit(In_sync, &rdev->flags)) { |
14f8d26b | 2796 | /* The ReadError flag will just be confusing now */ |
4e5314b5 N |
2797 | clear_bit(R5_ReadError, &dev->flags); |
2798 | clear_bit(R5_ReWrite, &dev->flags); | |
2799 | } | |
b2d444d7 | 2800 | if (!rdev || !test_bit(In_sync, &rdev->flags) |
4e5314b5 | 2801 | || test_bit(R5_ReadError, &dev->flags)) { |
a4456856 DW |
2802 | s.failed++; |
2803 | s.failed_num = i; | |
1da177e4 LT |
2804 | } else |
2805 | set_bit(R5_Insync, &dev->flags); | |
2806 | } | |
9910f16a | 2807 | rcu_read_unlock(); |
b5e98d65 | 2808 | |
6bfe0b49 | 2809 | if (unlikely(blocked_rdev)) { |
ac4090d2 N |
2810 | if (s.syncing || s.expanding || s.expanded || |
2811 | s.to_write || s.written) { | |
2812 | set_bit(STRIPE_HANDLE, &sh->state); | |
2813 | goto unlock; | |
2814 | } | |
2815 | /* There is nothing for the blocked_rdev to block */ | |
2816 | rdev_dec_pending(blocked_rdev, conf->mddev); | |
2817 | blocked_rdev = NULL; | |
6bfe0b49 DW |
2818 | } |
2819 | ||
83de75cc DW |
2820 | if (s.to_fill && !test_bit(STRIPE_BIOFILL_RUN, &sh->state)) { |
2821 | set_bit(STRIPE_OP_BIOFILL, &s.ops_request); | |
2822 | set_bit(STRIPE_BIOFILL_RUN, &sh->state); | |
2823 | } | |
b5e98d65 | 2824 | |
45b4233c | 2825 | pr_debug("locked=%d uptodate=%d to_read=%d" |
1da177e4 | 2826 | " to_write=%d failed=%d failed_num=%d\n", |
a4456856 DW |
2827 | s.locked, s.uptodate, s.to_read, s.to_write, |
2828 | s.failed, s.failed_num); | |
1da177e4 LT |
2829 | /* check if the array has lost two devices and, if so, some requests might |
2830 | * need to be failed | |
2831 | */ | |
a4456856 | 2832 | if (s.failed > 1 && s.to_read+s.to_write+s.written) |
1fe797e6 | 2833 | handle_failed_stripe(conf, sh, &s, disks, &return_bi); |
a4456856 | 2834 | if (s.failed > 1 && s.syncing) { |
1da177e4 LT |
2835 | md_done_sync(conf->mddev, STRIPE_SECTORS,0); |
2836 | clear_bit(STRIPE_SYNCING, &sh->state); | |
a4456856 | 2837 | s.syncing = 0; |
1da177e4 LT |
2838 | } |
2839 | ||
2840 | /* might be able to return some write requests if the parity block | |
2841 | * is safe, or on a failed drive | |
2842 | */ | |
2843 | dev = &sh->dev[sh->pd_idx]; | |
a4456856 DW |
2844 | if ( s.written && |
2845 | ((test_bit(R5_Insync, &dev->flags) && | |
2846 | !test_bit(R5_LOCKED, &dev->flags) && | |
2847 | test_bit(R5_UPTODATE, &dev->flags)) || | |
2848 | (s.failed == 1 && s.failed_num == sh->pd_idx))) | |
1fe797e6 | 2849 | handle_stripe_clean_event(conf, sh, disks, &return_bi); |
1da177e4 LT |
2850 | |
2851 | /* Now we might consider reading some blocks, either to check/generate | |
2852 | * parity, or to satisfy requests | |
2853 | * or to load a block that is being partially written. | |
2854 | */ | |
a4456856 | 2855 | if (s.to_read || s.non_overwrite || |
976ea8d4 | 2856 | (s.syncing && (s.uptodate + s.compute < disks)) || s.expanding) |
1fe797e6 | 2857 | handle_stripe_fill5(sh, &s, disks); |
1da177e4 | 2858 | |
e33129d8 DW |
2859 | /* Now we check to see if any write operations have recently |
2860 | * completed | |
2861 | */ | |
e0a115e5 | 2862 | prexor = 0; |
d8ee0728 | 2863 | if (sh->reconstruct_state == reconstruct_state_prexor_drain_result) |
e0a115e5 | 2864 | prexor = 1; |
d8ee0728 DW |
2865 | if (sh->reconstruct_state == reconstruct_state_drain_result || |
2866 | sh->reconstruct_state == reconstruct_state_prexor_drain_result) { | |
600aa109 | 2867 | sh->reconstruct_state = reconstruct_state_idle; |
e33129d8 DW |
2868 | |
2869 | /* All the 'written' buffers and the parity block are ready to | |
2870 | * be written back to disk | |
2871 | */ | |
2872 | BUG_ON(!test_bit(R5_UPTODATE, &sh->dev[sh->pd_idx].flags)); | |
2873 | for (i = disks; i--; ) { | |
2874 | dev = &sh->dev[i]; | |
2875 | if (test_bit(R5_LOCKED, &dev->flags) && | |
2876 | (i == sh->pd_idx || dev->written)) { | |
2877 | pr_debug("Writing block %d\n", i); | |
2878 | set_bit(R5_Wantwrite, &dev->flags); | |
e0a115e5 DW |
2879 | if (prexor) |
2880 | continue; | |
e33129d8 DW |
2881 | if (!test_bit(R5_Insync, &dev->flags) || |
2882 | (i == sh->pd_idx && s.failed == 0)) | |
2883 | set_bit(STRIPE_INSYNC, &sh->state); | |
2884 | } | |
2885 | } | |
2886 | if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
2887 | atomic_dec(&conf->preread_active_stripes); | |
2888 | if (atomic_read(&conf->preread_active_stripes) < | |
2889 | IO_THRESHOLD) | |
2890 | md_wakeup_thread(conf->mddev->thread); | |
2891 | } | |
2892 | } | |
2893 | ||
2894 | /* Now to consider new write requests and what else, if anything | |
2895 | * should be read. We do not handle new writes when: | |
2896 | * 1/ A 'write' operation (copy+xor) is already in flight. | |
2897 | * 2/ A 'check' operation is in flight, as it may clobber the parity | |
2898 | * block. | |
2899 | */ | |
600aa109 | 2900 | if (s.to_write && !sh->reconstruct_state && !sh->check_state) |
1fe797e6 | 2901 | handle_stripe_dirtying5(conf, sh, &s, disks); |
1da177e4 LT |
2902 | |
2903 | /* maybe we need to check and possibly fix the parity for this stripe | |
e89f8962 DW |
2904 | * Any reads will already have been scheduled, so we just see if enough |
2905 | * data is available. The parity check is held off while parity | |
2906 | * dependent operations are in flight. | |
1da177e4 | 2907 | */ |
ecc65c9b DW |
2908 | if (sh->check_state || |
2909 | (s.syncing && s.locked == 0 && | |
976ea8d4 | 2910 | !test_bit(STRIPE_COMPUTE_RUN, &sh->state) && |
ecc65c9b | 2911 | !test_bit(STRIPE_INSYNC, &sh->state))) |
a4456856 | 2912 | handle_parity_checks5(conf, sh, &s, disks); |
e89f8962 | 2913 | |
a4456856 | 2914 | if (s.syncing && s.locked == 0 && test_bit(STRIPE_INSYNC, &sh->state)) { |
1da177e4 LT |
2915 | md_done_sync(conf->mddev, STRIPE_SECTORS,1); |
2916 | clear_bit(STRIPE_SYNCING, &sh->state); | |
2917 | } | |
4e5314b5 N |
2918 | |
2919 | /* If the failed drive is just a ReadError, then we might need to progress | |
2920 | * the repair/check process | |
2921 | */ | |
a4456856 DW |
2922 | if (s.failed == 1 && !conf->mddev->ro && |
2923 | test_bit(R5_ReadError, &sh->dev[s.failed_num].flags) | |
2924 | && !test_bit(R5_LOCKED, &sh->dev[s.failed_num].flags) | |
2925 | && test_bit(R5_UPTODATE, &sh->dev[s.failed_num].flags) | |
4e5314b5 | 2926 | ) { |
a4456856 | 2927 | dev = &sh->dev[s.failed_num]; |
4e5314b5 N |
2928 | if (!test_bit(R5_ReWrite, &dev->flags)) { |
2929 | set_bit(R5_Wantwrite, &dev->flags); | |
2930 | set_bit(R5_ReWrite, &dev->flags); | |
2931 | set_bit(R5_LOCKED, &dev->flags); | |
a4456856 | 2932 | s.locked++; |
4e5314b5 N |
2933 | } else { |
2934 | /* let's read it back */ | |
2935 | set_bit(R5_Wantread, &dev->flags); | |
2936 | set_bit(R5_LOCKED, &dev->flags); | |
a4456856 | 2937 | s.locked++; |
4e5314b5 N |
2938 | } |
2939 | } | |
2940 | ||
600aa109 DW |
2941 | /* Finish reconstruct operations initiated by the expansion process */ |
2942 | if (sh->reconstruct_state == reconstruct_state_result) { | |
2943 | sh->reconstruct_state = reconstruct_state_idle; | |
f0a50d37 | 2944 | clear_bit(STRIPE_EXPANDING, &sh->state); |
23397883 | 2945 | for (i = conf->raid_disks; i--; ) { |
ccfcc3c1 | 2946 | set_bit(R5_Wantwrite, &sh->dev[i].flags); |
23397883 | 2947 | set_bit(R5_LOCKED, &sh->dev[i].flags); |
efe31143 | 2948 | s.locked++; |
23397883 | 2949 | } |
f0a50d37 DW |
2950 | } |
2951 | ||
2952 | if (s.expanded && test_bit(STRIPE_EXPANDING, &sh->state) && | |
600aa109 | 2953 | !sh->reconstruct_state) { |
f0a50d37 DW |
2954 | /* Need to write out all blocks after computing parity */ |
2955 | sh->disks = conf->raid_disks; | |
911d4ee8 | 2956 | stripe_set_idx(sh->sector, conf, 0, sh); |
1fe797e6 | 2957 | schedule_reconstruction5(sh, &s, 1, 1); |
600aa109 | 2958 | } else if (s.expanded && !sh->reconstruct_state && s.locked == 0) { |
ccfcc3c1 | 2959 | clear_bit(STRIPE_EXPAND_READY, &sh->state); |
f6705578 | 2960 | atomic_dec(&conf->reshape_stripes); |
ccfcc3c1 N |
2961 | wake_up(&conf->wait_for_overlap); |
2962 | md_done_sync(conf->mddev, STRIPE_SECTORS, 1); | |
2963 | } | |
2964 | ||
0f94e87c | 2965 | if (s.expanding && s.locked == 0 && |
976ea8d4 | 2966 | !test_bit(STRIPE_COMPUTE_RUN, &sh->state)) |
a4456856 | 2967 | handle_stripe_expansion(conf, sh, NULL); |
ccfcc3c1 | 2968 | |
6bfe0b49 | 2969 | unlock: |
1da177e4 LT |
2970 | spin_unlock(&sh->lock); |
2971 | ||
6bfe0b49 DW |
2972 | /* wait for this device to become unblocked */ |
2973 | if (unlikely(blocked_rdev)) | |
2974 | md_wait_for_blocked_rdev(blocked_rdev, conf->mddev); | |
2975 | ||
600aa109 DW |
2976 | if (s.ops_request) |
2977 | raid5_run_ops(sh, s.ops_request); | |
d84e0f10 | 2978 | |
c4e5ac0a | 2979 | ops_run_io(sh, &s); |
1da177e4 | 2980 | |
a4456856 | 2981 | return_io(return_bi); |
df10cfbc DW |
2982 | |
2983 | return blocked_rdev == NULL; | |
1da177e4 LT |
2984 | } |
2985 | ||
df10cfbc | 2986 | static bool handle_stripe6(struct stripe_head *sh, struct page *tmp_page) |
1da177e4 | 2987 | { |
bff61975 | 2988 | raid5_conf_t *conf = sh->raid_conf; |
f416885e | 2989 | int disks = sh->disks; |
a4456856 | 2990 | struct bio *return_bi = NULL; |
34e04e87 | 2991 | int i, pd_idx = sh->pd_idx, qd_idx = sh->qd_idx; |
a4456856 DW |
2992 | struct stripe_head_state s; |
2993 | struct r6_state r6s; | |
16a53ecc | 2994 | struct r5dev *dev, *pdev, *qdev; |
6bfe0b49 | 2995 | mdk_rdev_t *blocked_rdev = NULL; |
1da177e4 | 2996 | |
45b4233c | 2997 | pr_debug("handling stripe %llu, state=%#lx cnt=%d, " |
a4456856 DW |
2998 | "pd_idx=%d, qd_idx=%d\n", |
2999 | (unsigned long long)sh->sector, sh->state, | |
34e04e87 | 3000 | atomic_read(&sh->count), pd_idx, qd_idx); |
a4456856 | 3001 | memset(&s, 0, sizeof(s)); |
72626685 | 3002 | |
16a53ecc N |
3003 | spin_lock(&sh->lock); |
3004 | clear_bit(STRIPE_HANDLE, &sh->state); | |
3005 | clear_bit(STRIPE_DELAYED, &sh->state); | |
3006 | ||
a4456856 DW |
3007 | s.syncing = test_bit(STRIPE_SYNCING, &sh->state); |
3008 | s.expanding = test_bit(STRIPE_EXPAND_SOURCE, &sh->state); | |
3009 | s.expanded = test_bit(STRIPE_EXPAND_READY, &sh->state); | |
16a53ecc | 3010 | /* Now to look around and see what can be done */ |
1da177e4 LT |
3011 | |
3012 | rcu_read_lock(); | |
16a53ecc N |
3013 | for (i=disks; i--; ) { |
3014 | mdk_rdev_t *rdev; | |
3015 | dev = &sh->dev[i]; | |
3016 | clear_bit(R5_Insync, &dev->flags); | |
1da177e4 | 3017 | |
45b4233c | 3018 | pr_debug("check %d: state 0x%lx read %p write %p written %p\n", |
16a53ecc N |
3019 | i, dev->flags, dev->toread, dev->towrite, dev->written); |
3020 | /* maybe we can reply to a read */ | |
3021 | if (test_bit(R5_UPTODATE, &dev->flags) && dev->toread) { | |
3022 | struct bio *rbi, *rbi2; | |
45b4233c | 3023 | pr_debug("Return read for disc %d\n", i); |
16a53ecc N |
3024 | spin_lock_irq(&conf->device_lock); |
3025 | rbi = dev->toread; | |
3026 | dev->toread = NULL; | |
3027 | if (test_and_clear_bit(R5_Overlap, &dev->flags)) | |
3028 | wake_up(&conf->wait_for_overlap); | |
3029 | spin_unlock_irq(&conf->device_lock); | |
3030 | while (rbi && rbi->bi_sector < dev->sector + STRIPE_SECTORS) { | |
3031 | copy_data(0, rbi, dev->page, dev->sector); | |
3032 | rbi2 = r5_next_bio(rbi, dev->sector); | |
3033 | spin_lock_irq(&conf->device_lock); | |
960e739d | 3034 | if (!raid5_dec_bi_phys_segments(rbi)) { |
16a53ecc N |
3035 | rbi->bi_next = return_bi; |
3036 | return_bi = rbi; | |
3037 | } | |
3038 | spin_unlock_irq(&conf->device_lock); | |
3039 | rbi = rbi2; | |
3040 | } | |
3041 | } | |
1da177e4 | 3042 | |
16a53ecc | 3043 | /* now count some things */ |
a4456856 DW |
3044 | if (test_bit(R5_LOCKED, &dev->flags)) s.locked++; |
3045 | if (test_bit(R5_UPTODATE, &dev->flags)) s.uptodate++; | |
1da177e4 | 3046 | |
16a53ecc | 3047 | |
a4456856 DW |
3048 | if (dev->toread) |
3049 | s.to_read++; | |
16a53ecc | 3050 | if (dev->towrite) { |
a4456856 | 3051 | s.to_write++; |
16a53ecc | 3052 | if (!test_bit(R5_OVERWRITE, &dev->flags)) |
a4456856 | 3053 | s.non_overwrite++; |
16a53ecc | 3054 | } |
a4456856 DW |
3055 | if (dev->written) |
3056 | s.written++; | |
16a53ecc | 3057 | rdev = rcu_dereference(conf->disks[i].rdev); |
ac4090d2 N |
3058 | if (blocked_rdev == NULL && |
3059 | rdev && unlikely(test_bit(Blocked, &rdev->flags))) { | |
6bfe0b49 DW |
3060 | blocked_rdev = rdev; |
3061 | atomic_inc(&rdev->nr_pending); | |
6bfe0b49 | 3062 | } |
16a53ecc N |
3063 | if (!rdev || !test_bit(In_sync, &rdev->flags)) { |
3064 | /* The ReadError flag will just be confusing now */ | |
3065 | clear_bit(R5_ReadError, &dev->flags); | |
3066 | clear_bit(R5_ReWrite, &dev->flags); | |
1da177e4 | 3067 | } |
16a53ecc N |
3068 | if (!rdev || !test_bit(In_sync, &rdev->flags) |
3069 | || test_bit(R5_ReadError, &dev->flags)) { | |
a4456856 DW |
3070 | if (s.failed < 2) |
3071 | r6s.failed_num[s.failed] = i; | |
3072 | s.failed++; | |
16a53ecc N |
3073 | } else |
3074 | set_bit(R5_Insync, &dev->flags); | |
1da177e4 LT |
3075 | } |
3076 | rcu_read_unlock(); | |
6bfe0b49 DW |
3077 | |
3078 | if (unlikely(blocked_rdev)) { | |
ac4090d2 N |
3079 | if (s.syncing || s.expanding || s.expanded || |
3080 | s.to_write || s.written) { | |
3081 | set_bit(STRIPE_HANDLE, &sh->state); | |
3082 | goto unlock; | |
3083 | } | |
3084 | /* There is nothing for the blocked_rdev to block */ | |
3085 | rdev_dec_pending(blocked_rdev, conf->mddev); | |
3086 | blocked_rdev = NULL; | |
6bfe0b49 | 3087 | } |
ac4090d2 | 3088 | |
45b4233c | 3089 | pr_debug("locked=%d uptodate=%d to_read=%d" |
16a53ecc | 3090 | " to_write=%d failed=%d failed_num=%d,%d\n", |
a4456856 DW |
3091 | s.locked, s.uptodate, s.to_read, s.to_write, s.failed, |
3092 | r6s.failed_num[0], r6s.failed_num[1]); | |
3093 | /* check if the array has lost >2 devices and, if so, some requests | |
3094 | * might need to be failed | |
16a53ecc | 3095 | */ |
a4456856 | 3096 | if (s.failed > 2 && s.to_read+s.to_write+s.written) |
1fe797e6 | 3097 | handle_failed_stripe(conf, sh, &s, disks, &return_bi); |
a4456856 | 3098 | if (s.failed > 2 && s.syncing) { |
16a53ecc N |
3099 | md_done_sync(conf->mddev, STRIPE_SECTORS,0); |
3100 | clear_bit(STRIPE_SYNCING, &sh->state); | |
a4456856 | 3101 | s.syncing = 0; |
16a53ecc N |
3102 | } |
3103 | ||
3104 | /* | |
3105 | * might be able to return some write requests if the parity blocks | |
3106 | * are safe, or on a failed drive | |
3107 | */ | |
3108 | pdev = &sh->dev[pd_idx]; | |
a4456856 DW |
3109 | r6s.p_failed = (s.failed >= 1 && r6s.failed_num[0] == pd_idx) |
3110 | || (s.failed >= 2 && r6s.failed_num[1] == pd_idx); | |
34e04e87 N |
3111 | qdev = &sh->dev[qd_idx]; |
3112 | r6s.q_failed = (s.failed >= 1 && r6s.failed_num[0] == qd_idx) | |
3113 | || (s.failed >= 2 && r6s.failed_num[1] == qd_idx); | |
a4456856 DW |
3114 | |
3115 | if ( s.written && | |
3116 | ( r6s.p_failed || ((test_bit(R5_Insync, &pdev->flags) | |
16a53ecc | 3117 | && !test_bit(R5_LOCKED, &pdev->flags) |
a4456856 DW |
3118 | && test_bit(R5_UPTODATE, &pdev->flags)))) && |
3119 | ( r6s.q_failed || ((test_bit(R5_Insync, &qdev->flags) | |
16a53ecc | 3120 | && !test_bit(R5_LOCKED, &qdev->flags) |
a4456856 | 3121 | && test_bit(R5_UPTODATE, &qdev->flags))))) |
1fe797e6 | 3122 | handle_stripe_clean_event(conf, sh, disks, &return_bi); |
16a53ecc N |
3123 | |
3124 | /* Now we might consider reading some blocks, either to check/generate | |
3125 | * parity, or to satisfy requests | |
3126 | * or to load a block that is being partially written. | |
3127 | */ | |
a4456856 DW |
3128 | if (s.to_read || s.non_overwrite || (s.to_write && s.failed) || |
3129 | (s.syncing && (s.uptodate < disks)) || s.expanding) | |
1fe797e6 | 3130 | handle_stripe_fill6(sh, &s, &r6s, disks); |
16a53ecc N |
3131 | |
3132 | /* now to consider writing and what else, if anything should be read */ | |
a4456856 | 3133 | if (s.to_write) |
1fe797e6 | 3134 | handle_stripe_dirtying6(conf, sh, &s, &r6s, disks); |
16a53ecc N |
3135 | |
3136 | /* maybe we need to check and possibly fix the parity for this stripe | |
a4456856 DW |
3137 | * Any reads will already have been scheduled, so we just see if enough |
3138 | * data is available | |
16a53ecc | 3139 | */ |
a4456856 DW |
3140 | if (s.syncing && s.locked == 0 && !test_bit(STRIPE_INSYNC, &sh->state)) |
3141 | handle_parity_checks6(conf, sh, &s, &r6s, tmp_page, disks); | |
16a53ecc | 3142 | |
a4456856 | 3143 | if (s.syncing && s.locked == 0 && test_bit(STRIPE_INSYNC, &sh->state)) { |
16a53ecc N |
3144 | md_done_sync(conf->mddev, STRIPE_SECTORS,1); |
3145 | clear_bit(STRIPE_SYNCING, &sh->state); | |
3146 | } | |
3147 | ||
3148 | /* If the failed drives are just a ReadError, then we might need | |
3149 | * to progress the repair/check process | |
3150 | */ | |
a4456856 DW |
3151 | if (s.failed <= 2 && !conf->mddev->ro) |
3152 | for (i = 0; i < s.failed; i++) { | |
3153 | dev = &sh->dev[r6s.failed_num[i]]; | |
16a53ecc N |
3154 | if (test_bit(R5_ReadError, &dev->flags) |
3155 | && !test_bit(R5_LOCKED, &dev->flags) | |
3156 | && test_bit(R5_UPTODATE, &dev->flags) | |
3157 | ) { | |
3158 | if (!test_bit(R5_ReWrite, &dev->flags)) { | |
3159 | set_bit(R5_Wantwrite, &dev->flags); | |
3160 | set_bit(R5_ReWrite, &dev->flags); | |
3161 | set_bit(R5_LOCKED, &dev->flags); | |
3162 | } else { | |
3163 | /* let's read it back */ | |
3164 | set_bit(R5_Wantread, &dev->flags); | |
3165 | set_bit(R5_LOCKED, &dev->flags); | |
3166 | } | |
3167 | } | |
3168 | } | |
f416885e | 3169 | |
a4456856 | 3170 | if (s.expanded && test_bit(STRIPE_EXPANDING, &sh->state)) { |
f416885e N |
3171 | /* Need to write out all blocks after computing P&Q */ |
3172 | sh->disks = conf->raid_disks; | |
911d4ee8 | 3173 | stripe_set_idx(sh->sector, conf, 0, sh); |
f416885e N |
3174 | compute_parity6(sh, RECONSTRUCT_WRITE); |
3175 | for (i = conf->raid_disks ; i-- ; ) { | |
3176 | set_bit(R5_LOCKED, &sh->dev[i].flags); | |
a4456856 | 3177 | s.locked++; |
f416885e N |
3178 | set_bit(R5_Wantwrite, &sh->dev[i].flags); |
3179 | } | |
3180 | clear_bit(STRIPE_EXPANDING, &sh->state); | |
a4456856 | 3181 | } else if (s.expanded) { |
f416885e N |
3182 | clear_bit(STRIPE_EXPAND_READY, &sh->state); |
3183 | atomic_dec(&conf->reshape_stripes); | |
3184 | wake_up(&conf->wait_for_overlap); | |
3185 | md_done_sync(conf->mddev, STRIPE_SECTORS, 1); | |
3186 | } | |
3187 | ||
0f94e87c | 3188 | if (s.expanding && s.locked == 0 && |
976ea8d4 | 3189 | !test_bit(STRIPE_COMPUTE_RUN, &sh->state)) |
a4456856 | 3190 | handle_stripe_expansion(conf, sh, &r6s); |
f416885e | 3191 | |
6bfe0b49 | 3192 | unlock: |
16a53ecc N |
3193 | spin_unlock(&sh->lock); |
3194 | ||
6bfe0b49 DW |
3195 | /* wait for this device to become unblocked */ |
3196 | if (unlikely(blocked_rdev)) | |
3197 | md_wait_for_blocked_rdev(blocked_rdev, conf->mddev); | |
3198 | ||
f0e43bcd | 3199 | ops_run_io(sh, &s); |
16a53ecc | 3200 | |
f0e43bcd | 3201 | return_io(return_bi); |
df10cfbc DW |
3202 | |
3203 | return blocked_rdev == NULL; | |
16a53ecc N |
3204 | } |
3205 | ||
df10cfbc DW |
3206 | /* returns true if the stripe was handled */ |
3207 | static bool handle_stripe(struct stripe_head *sh, struct page *tmp_page) | |
16a53ecc N |
3208 | { |
3209 | if (sh->raid_conf->level == 6) | |
df10cfbc | 3210 | return handle_stripe6(sh, tmp_page); |
16a53ecc | 3211 | else |
df10cfbc | 3212 | return handle_stripe5(sh); |
16a53ecc N |
3213 | } |
3214 | ||
3215 | ||
3216 | ||
3217 | static void raid5_activate_delayed(raid5_conf_t *conf) | |
3218 | { | |
3219 | if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD) { | |
3220 | while (!list_empty(&conf->delayed_list)) { | |
3221 | struct list_head *l = conf->delayed_list.next; | |
3222 | struct stripe_head *sh; | |
3223 | sh = list_entry(l, struct stripe_head, lru); | |
3224 | list_del_init(l); | |
3225 | clear_bit(STRIPE_DELAYED, &sh->state); | |
3226 | if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) | |
3227 | atomic_inc(&conf->preread_active_stripes); | |
8b3e6cdc | 3228 | list_add_tail(&sh->lru, &conf->hold_list); |
16a53ecc | 3229 | } |
6ed3003c N |
3230 | } else |
3231 | blk_plug_device(conf->mddev->queue); | |
16a53ecc N |
3232 | } |
3233 | ||
3234 | static void activate_bit_delay(raid5_conf_t *conf) | |
3235 | { | |
3236 | /* device_lock is held */ | |
3237 | struct list_head head; | |
3238 | list_add(&head, &conf->bitmap_list); | |
3239 | list_del_init(&conf->bitmap_list); | |
3240 | while (!list_empty(&head)) { | |
3241 | struct stripe_head *sh = list_entry(head.next, struct stripe_head, lru); | |
3242 | list_del_init(&sh->lru); | |
3243 | atomic_inc(&sh->count); | |
3244 | __release_stripe(conf, sh); | |
3245 | } | |
3246 | } | |
3247 | ||
3248 | static void unplug_slaves(mddev_t *mddev) | |
3249 | { | |
3250 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
3251 | int i; | |
3252 | ||
3253 | rcu_read_lock(); | |
3254 | for (i=0; i<mddev->raid_disks; i++) { | |
3255 | mdk_rdev_t *rdev = rcu_dereference(conf->disks[i].rdev); | |
3256 | if (rdev && !test_bit(Faulty, &rdev->flags) && atomic_read(&rdev->nr_pending)) { | |
165125e1 | 3257 | struct request_queue *r_queue = bdev_get_queue(rdev->bdev); |
16a53ecc N |
3258 | |
3259 | atomic_inc(&rdev->nr_pending); | |
3260 | rcu_read_unlock(); | |
3261 | ||
2ad8b1ef | 3262 | blk_unplug(r_queue); |
16a53ecc N |
3263 | |
3264 | rdev_dec_pending(rdev, mddev); | |
3265 | rcu_read_lock(); | |
3266 | } | |
3267 | } | |
3268 | rcu_read_unlock(); | |
3269 | } | |
3270 | ||
165125e1 | 3271 | static void raid5_unplug_device(struct request_queue *q) |
16a53ecc N |
3272 | { |
3273 | mddev_t *mddev = q->queuedata; | |
3274 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
3275 | unsigned long flags; | |
3276 | ||
3277 | spin_lock_irqsave(&conf->device_lock, flags); | |
3278 | ||
3279 | if (blk_remove_plug(q)) { | |
3280 | conf->seq_flush++; | |
3281 | raid5_activate_delayed(conf); | |
72626685 | 3282 | } |
1da177e4 LT |
3283 | md_wakeup_thread(mddev->thread); |
3284 | ||
3285 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
3286 | ||
3287 | unplug_slaves(mddev); | |
3288 | } | |
3289 | ||
f022b2fd N |
3290 | static int raid5_congested(void *data, int bits) |
3291 | { | |
3292 | mddev_t *mddev = data; | |
3293 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
3294 | ||
3295 | /* No difference between reads and writes. Just check | |
3296 | * how busy the stripe_cache is | |
3297 | */ | |
3298 | if (conf->inactive_blocked) | |
3299 | return 1; | |
3300 | if (conf->quiesce) | |
3301 | return 1; | |
3302 | if (list_empty_careful(&conf->inactive_list)) | |
3303 | return 1; | |
3304 | ||
3305 | return 0; | |
3306 | } | |
3307 | ||
23032a0e RBJ |
3308 | /* We want read requests to align with chunks where possible, |
3309 | * but write requests don't need to. | |
3310 | */ | |
cc371e66 AK |
3311 | static int raid5_mergeable_bvec(struct request_queue *q, |
3312 | struct bvec_merge_data *bvm, | |
3313 | struct bio_vec *biovec) | |
23032a0e RBJ |
3314 | { |
3315 | mddev_t *mddev = q->queuedata; | |
cc371e66 | 3316 | sector_t sector = bvm->bi_sector + get_start_sect(bvm->bi_bdev); |
23032a0e RBJ |
3317 | int max; |
3318 | unsigned int chunk_sectors = mddev->chunk_size >> 9; | |
cc371e66 | 3319 | unsigned int bio_sectors = bvm->bi_size >> 9; |
23032a0e | 3320 | |
cc371e66 | 3321 | if ((bvm->bi_rw & 1) == WRITE) |
23032a0e RBJ |
3322 | return biovec->bv_len; /* always allow writes to be mergeable */ |
3323 | ||
784052ec N |
3324 | if (mddev->new_chunk < mddev->chunk_size) |
3325 | chunk_sectors = mddev->new_chunk >> 9; | |
23032a0e RBJ |
3326 | max = (chunk_sectors - ((sector & (chunk_sectors - 1)) + bio_sectors)) << 9; |
3327 | if (max < 0) max = 0; | |
3328 | if (max <= biovec->bv_len && bio_sectors == 0) | |
3329 | return biovec->bv_len; | |
3330 | else | |
3331 | return max; | |
3332 | } | |
3333 | ||
f679623f RBJ |
3334 | |
3335 | static int in_chunk_boundary(mddev_t *mddev, struct bio *bio) | |
3336 | { | |
3337 | sector_t sector = bio->bi_sector + get_start_sect(bio->bi_bdev); | |
3338 | unsigned int chunk_sectors = mddev->chunk_size >> 9; | |
3339 | unsigned int bio_sectors = bio->bi_size >> 9; | |
3340 | ||
784052ec N |
3341 | if (mddev->new_chunk < mddev->chunk_size) |
3342 | chunk_sectors = mddev->new_chunk >> 9; | |
f679623f RBJ |
3343 | return chunk_sectors >= |
3344 | ((sector & (chunk_sectors - 1)) + bio_sectors); | |
3345 | } | |
3346 | ||
46031f9a RBJ |
3347 | /* |
3348 | * add bio to the retry LIFO ( in O(1) ... we are in interrupt ) | |
3349 | * later sampled by raid5d. | |
3350 | */ | |
3351 | static void add_bio_to_retry(struct bio *bi,raid5_conf_t *conf) | |
3352 | { | |
3353 | unsigned long flags; | |
3354 | ||
3355 | spin_lock_irqsave(&conf->device_lock, flags); | |
3356 | ||
3357 | bi->bi_next = conf->retry_read_aligned_list; | |
3358 | conf->retry_read_aligned_list = bi; | |
3359 | ||
3360 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
3361 | md_wakeup_thread(conf->mddev->thread); | |
3362 | } | |
3363 | ||
3364 | ||
3365 | static struct bio *remove_bio_from_retry(raid5_conf_t *conf) | |
3366 | { | |
3367 | struct bio *bi; | |
3368 | ||
3369 | bi = conf->retry_read_aligned; | |
3370 | if (bi) { | |
3371 | conf->retry_read_aligned = NULL; | |
3372 | return bi; | |
3373 | } | |
3374 | bi = conf->retry_read_aligned_list; | |
3375 | if(bi) { | |
387bb173 | 3376 | conf->retry_read_aligned_list = bi->bi_next; |
46031f9a | 3377 | bi->bi_next = NULL; |
960e739d JA |
3378 | /* |
3379 | * this sets the active strip count to 1 and the processed | |
3380 | * strip count to zero (upper 8 bits) | |
3381 | */ | |
46031f9a | 3382 | bi->bi_phys_segments = 1; /* biased count of active stripes */ |
46031f9a RBJ |
3383 | } |
3384 | ||
3385 | return bi; | |
3386 | } | |
3387 | ||
3388 | ||
f679623f RBJ |
3389 | /* |
3390 | * The "raid5_align_endio" should check if the read succeeded and if it | |
3391 | * did, call bio_endio on the original bio (having bio_put the new bio | |
3392 | * first). | |
3393 | * If the read failed.. | |
3394 | */ | |
6712ecf8 | 3395 | static void raid5_align_endio(struct bio *bi, int error) |
f679623f RBJ |
3396 | { |
3397 | struct bio* raid_bi = bi->bi_private; | |
46031f9a RBJ |
3398 | mddev_t *mddev; |
3399 | raid5_conf_t *conf; | |
3400 | int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags); | |
3401 | mdk_rdev_t *rdev; | |
3402 | ||
f679623f | 3403 | bio_put(bi); |
46031f9a RBJ |
3404 | |
3405 | mddev = raid_bi->bi_bdev->bd_disk->queue->queuedata; | |
3406 | conf = mddev_to_conf(mddev); | |
3407 | rdev = (void*)raid_bi->bi_next; | |
3408 | raid_bi->bi_next = NULL; | |
3409 | ||
3410 | rdev_dec_pending(rdev, conf->mddev); | |
3411 | ||
3412 | if (!error && uptodate) { | |
6712ecf8 | 3413 | bio_endio(raid_bi, 0); |
46031f9a RBJ |
3414 | if (atomic_dec_and_test(&conf->active_aligned_reads)) |
3415 | wake_up(&conf->wait_for_stripe); | |
6712ecf8 | 3416 | return; |
46031f9a RBJ |
3417 | } |
3418 | ||
3419 | ||
45b4233c | 3420 | pr_debug("raid5_align_endio : io error...handing IO for a retry\n"); |
46031f9a RBJ |
3421 | |
3422 | add_bio_to_retry(raid_bi, conf); | |
f679623f RBJ |
3423 | } |
3424 | ||
387bb173 NB |
3425 | static int bio_fits_rdev(struct bio *bi) |
3426 | { | |
165125e1 | 3427 | struct request_queue *q = bdev_get_queue(bi->bi_bdev); |
387bb173 NB |
3428 | |
3429 | if ((bi->bi_size>>9) > q->max_sectors) | |
3430 | return 0; | |
3431 | blk_recount_segments(q, bi); | |
960e739d | 3432 | if (bi->bi_phys_segments > q->max_phys_segments) |
387bb173 NB |
3433 | return 0; |
3434 | ||
3435 | if (q->merge_bvec_fn) | |
3436 | /* it's too hard to apply the merge_bvec_fn at this stage, | |
3437 | * just just give up | |
3438 | */ | |
3439 | return 0; | |
3440 | ||
3441 | return 1; | |
3442 | } | |
3443 | ||
3444 | ||
165125e1 | 3445 | static int chunk_aligned_read(struct request_queue *q, struct bio * raid_bio) |
f679623f RBJ |
3446 | { |
3447 | mddev_t *mddev = q->queuedata; | |
3448 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
911d4ee8 | 3449 | unsigned int dd_idx; |
f679623f RBJ |
3450 | struct bio* align_bi; |
3451 | mdk_rdev_t *rdev; | |
3452 | ||
3453 | if (!in_chunk_boundary(mddev, raid_bio)) { | |
45b4233c | 3454 | pr_debug("chunk_aligned_read : non aligned\n"); |
f679623f RBJ |
3455 | return 0; |
3456 | } | |
3457 | /* | |
99c0fb5f | 3458 | * use bio_clone to make a copy of the bio |
f679623f RBJ |
3459 | */ |
3460 | align_bi = bio_clone(raid_bio, GFP_NOIO); | |
3461 | if (!align_bi) | |
3462 | return 0; | |
3463 | /* | |
3464 | * set bi_end_io to a new function, and set bi_private to the | |
3465 | * original bio. | |
3466 | */ | |
3467 | align_bi->bi_end_io = raid5_align_endio; | |
3468 | align_bi->bi_private = raid_bio; | |
3469 | /* | |
3470 | * compute position | |
3471 | */ | |
112bf897 N |
3472 | align_bi->bi_sector = raid5_compute_sector(conf, raid_bio->bi_sector, |
3473 | 0, | |
911d4ee8 | 3474 | &dd_idx, NULL); |
f679623f RBJ |
3475 | |
3476 | rcu_read_lock(); | |
3477 | rdev = rcu_dereference(conf->disks[dd_idx].rdev); | |
3478 | if (rdev && test_bit(In_sync, &rdev->flags)) { | |
f679623f RBJ |
3479 | atomic_inc(&rdev->nr_pending); |
3480 | rcu_read_unlock(); | |
46031f9a RBJ |
3481 | raid_bio->bi_next = (void*)rdev; |
3482 | align_bi->bi_bdev = rdev->bdev; | |
3483 | align_bi->bi_flags &= ~(1 << BIO_SEG_VALID); | |
3484 | align_bi->bi_sector += rdev->data_offset; | |
3485 | ||
387bb173 NB |
3486 | if (!bio_fits_rdev(align_bi)) { |
3487 | /* too big in some way */ | |
3488 | bio_put(align_bi); | |
3489 | rdev_dec_pending(rdev, mddev); | |
3490 | return 0; | |
3491 | } | |
3492 | ||
46031f9a RBJ |
3493 | spin_lock_irq(&conf->device_lock); |
3494 | wait_event_lock_irq(conf->wait_for_stripe, | |
3495 | conf->quiesce == 0, | |
3496 | conf->device_lock, /* nothing */); | |
3497 | atomic_inc(&conf->active_aligned_reads); | |
3498 | spin_unlock_irq(&conf->device_lock); | |
3499 | ||
f679623f RBJ |
3500 | generic_make_request(align_bi); |
3501 | return 1; | |
3502 | } else { | |
3503 | rcu_read_unlock(); | |
46031f9a | 3504 | bio_put(align_bi); |
f679623f RBJ |
3505 | return 0; |
3506 | } | |
3507 | } | |
3508 | ||
8b3e6cdc DW |
3509 | /* __get_priority_stripe - get the next stripe to process |
3510 | * | |
3511 | * Full stripe writes are allowed to pass preread active stripes up until | |
3512 | * the bypass_threshold is exceeded. In general the bypass_count | |
3513 | * increments when the handle_list is handled before the hold_list; however, it | |
3514 | * will not be incremented when STRIPE_IO_STARTED is sampled set signifying a | |
3515 | * stripe with in flight i/o. The bypass_count will be reset when the | |
3516 | * head of the hold_list has changed, i.e. the head was promoted to the | |
3517 | * handle_list. | |
3518 | */ | |
3519 | static struct stripe_head *__get_priority_stripe(raid5_conf_t *conf) | |
3520 | { | |
3521 | struct stripe_head *sh; | |
3522 | ||
3523 | pr_debug("%s: handle: %s hold: %s full_writes: %d bypass_count: %d\n", | |
3524 | __func__, | |
3525 | list_empty(&conf->handle_list) ? "empty" : "busy", | |
3526 | list_empty(&conf->hold_list) ? "empty" : "busy", | |
3527 | atomic_read(&conf->pending_full_writes), conf->bypass_count); | |
3528 | ||
3529 | if (!list_empty(&conf->handle_list)) { | |
3530 | sh = list_entry(conf->handle_list.next, typeof(*sh), lru); | |
3531 | ||
3532 | if (list_empty(&conf->hold_list)) | |
3533 | conf->bypass_count = 0; | |
3534 | else if (!test_bit(STRIPE_IO_STARTED, &sh->state)) { | |
3535 | if (conf->hold_list.next == conf->last_hold) | |
3536 | conf->bypass_count++; | |
3537 | else { | |
3538 | conf->last_hold = conf->hold_list.next; | |
3539 | conf->bypass_count -= conf->bypass_threshold; | |
3540 | if (conf->bypass_count < 0) | |
3541 | conf->bypass_count = 0; | |
3542 | } | |
3543 | } | |
3544 | } else if (!list_empty(&conf->hold_list) && | |
3545 | ((conf->bypass_threshold && | |
3546 | conf->bypass_count > conf->bypass_threshold) || | |
3547 | atomic_read(&conf->pending_full_writes) == 0)) { | |
3548 | sh = list_entry(conf->hold_list.next, | |
3549 | typeof(*sh), lru); | |
3550 | conf->bypass_count -= conf->bypass_threshold; | |
3551 | if (conf->bypass_count < 0) | |
3552 | conf->bypass_count = 0; | |
3553 | } else | |
3554 | return NULL; | |
3555 | ||
3556 | list_del_init(&sh->lru); | |
3557 | atomic_inc(&sh->count); | |
3558 | BUG_ON(atomic_read(&sh->count) != 1); | |
3559 | return sh; | |
3560 | } | |
f679623f | 3561 | |
165125e1 | 3562 | static int make_request(struct request_queue *q, struct bio * bi) |
1da177e4 LT |
3563 | { |
3564 | mddev_t *mddev = q->queuedata; | |
3565 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
911d4ee8 | 3566 | int dd_idx; |
1da177e4 LT |
3567 | sector_t new_sector; |
3568 | sector_t logical_sector, last_sector; | |
3569 | struct stripe_head *sh; | |
a362357b | 3570 | const int rw = bio_data_dir(bi); |
c9959059 | 3571 | int cpu, remaining; |
1da177e4 | 3572 | |
e5dcdd80 | 3573 | if (unlikely(bio_barrier(bi))) { |
6712ecf8 | 3574 | bio_endio(bi, -EOPNOTSUPP); |
e5dcdd80 N |
3575 | return 0; |
3576 | } | |
3577 | ||
3d310eb7 | 3578 | md_write_start(mddev, bi); |
06d91a5f | 3579 | |
074a7aca TH |
3580 | cpu = part_stat_lock(); |
3581 | part_stat_inc(cpu, &mddev->gendisk->part0, ios[rw]); | |
3582 | part_stat_add(cpu, &mddev->gendisk->part0, sectors[rw], | |
3583 | bio_sectors(bi)); | |
3584 | part_stat_unlock(); | |
1da177e4 | 3585 | |
802ba064 | 3586 | if (rw == READ && |
52488615 RBJ |
3587 | mddev->reshape_position == MaxSector && |
3588 | chunk_aligned_read(q,bi)) | |
99c0fb5f | 3589 | return 0; |
52488615 | 3590 | |
1da177e4 LT |
3591 | logical_sector = bi->bi_sector & ~((sector_t)STRIPE_SECTORS-1); |
3592 | last_sector = bi->bi_sector + (bi->bi_size>>9); | |
3593 | bi->bi_next = NULL; | |
3594 | bi->bi_phys_segments = 1; /* over-loaded to count active stripes */ | |
06d91a5f | 3595 | |
1da177e4 LT |
3596 | for (;logical_sector < last_sector; logical_sector += STRIPE_SECTORS) { |
3597 | DEFINE_WAIT(w); | |
16a53ecc | 3598 | int disks, data_disks; |
b5663ba4 | 3599 | int previous; |
b578d55f | 3600 | |
7ecaa1e6 | 3601 | retry: |
b5663ba4 | 3602 | previous = 0; |
b578d55f | 3603 | prepare_to_wait(&conf->wait_for_overlap, &w, TASK_UNINTERRUPTIBLE); |
fef9c61f | 3604 | if (likely(conf->reshape_progress == MaxSector)) |
7ecaa1e6 N |
3605 | disks = conf->raid_disks; |
3606 | else { | |
fef9c61f | 3607 | /* spinlock is needed as reshape_progress may be |
df8e7f76 N |
3608 | * 64bit on a 32bit platform, and so it might be |
3609 | * possible to see a half-updated value | |
fef9c61f | 3610 | * Ofcourse reshape_progress could change after |
df8e7f76 N |
3611 | * the lock is dropped, so once we get a reference |
3612 | * to the stripe that we think it is, we will have | |
3613 | * to check again. | |
3614 | */ | |
7ecaa1e6 N |
3615 | spin_lock_irq(&conf->device_lock); |
3616 | disks = conf->raid_disks; | |
fef9c61f N |
3617 | if (mddev->delta_disks < 0 |
3618 | ? logical_sector < conf->reshape_progress | |
3619 | : logical_sector >= conf->reshape_progress) { | |
7ecaa1e6 | 3620 | disks = conf->previous_raid_disks; |
b5663ba4 N |
3621 | previous = 1; |
3622 | } else { | |
fef9c61f N |
3623 | if (mddev->delta_disks < 0 |
3624 | ? logical_sector < conf->reshape_safe | |
3625 | : logical_sector >= conf->reshape_safe) { | |
b578d55f N |
3626 | spin_unlock_irq(&conf->device_lock); |
3627 | schedule(); | |
3628 | goto retry; | |
3629 | } | |
3630 | } | |
7ecaa1e6 N |
3631 | spin_unlock_irq(&conf->device_lock); |
3632 | } | |
16a53ecc N |
3633 | data_disks = disks - conf->max_degraded; |
3634 | ||
112bf897 N |
3635 | new_sector = raid5_compute_sector(conf, logical_sector, |
3636 | previous, | |
911d4ee8 | 3637 | &dd_idx, NULL); |
45b4233c | 3638 | pr_debug("raid5: make_request, sector %llu logical %llu\n", |
1da177e4 LT |
3639 | (unsigned long long)new_sector, |
3640 | (unsigned long long)logical_sector); | |
3641 | ||
b5663ba4 N |
3642 | sh = get_active_stripe(conf, new_sector, previous, |
3643 | (bi->bi_rw&RWA_MASK)); | |
1da177e4 | 3644 | if (sh) { |
fef9c61f | 3645 | if (unlikely(conf->reshape_progress != MaxSector)) { |
7ecaa1e6 | 3646 | /* expansion might have moved on while waiting for a |
df8e7f76 N |
3647 | * stripe, so we must do the range check again. |
3648 | * Expansion could still move past after this | |
3649 | * test, but as we are holding a reference to | |
3650 | * 'sh', we know that if that happens, | |
3651 | * STRIPE_EXPANDING will get set and the expansion | |
3652 | * won't proceed until we finish with the stripe. | |
7ecaa1e6 N |
3653 | */ |
3654 | int must_retry = 0; | |
3655 | spin_lock_irq(&conf->device_lock); | |
fef9c61f N |
3656 | if ((mddev->delta_disks < 0 |
3657 | ? logical_sector >= conf->reshape_progress | |
3658 | : logical_sector < conf->reshape_progress) | |
86b42c71 | 3659 | && previous) |
7ecaa1e6 N |
3660 | /* mismatch, need to try again */ |
3661 | must_retry = 1; | |
3662 | spin_unlock_irq(&conf->device_lock); | |
3663 | if (must_retry) { | |
3664 | release_stripe(sh); | |
3665 | goto retry; | |
3666 | } | |
3667 | } | |
e464eafd N |
3668 | /* FIXME what if we get a false positive because these |
3669 | * are being updated. | |
3670 | */ | |
3671 | if (logical_sector >= mddev->suspend_lo && | |
3672 | logical_sector < mddev->suspend_hi) { | |
3673 | release_stripe(sh); | |
3674 | schedule(); | |
3675 | goto retry; | |
3676 | } | |
7ecaa1e6 N |
3677 | |
3678 | if (test_bit(STRIPE_EXPANDING, &sh->state) || | |
3679 | !add_stripe_bio(sh, bi, dd_idx, (bi->bi_rw&RW_MASK))) { | |
3680 | /* Stripe is busy expanding or | |
3681 | * add failed due to overlap. Flush everything | |
1da177e4 LT |
3682 | * and wait a while |
3683 | */ | |
3684 | raid5_unplug_device(mddev->queue); | |
3685 | release_stripe(sh); | |
3686 | schedule(); | |
3687 | goto retry; | |
3688 | } | |
3689 | finish_wait(&conf->wait_for_overlap, &w); | |
6ed3003c N |
3690 | set_bit(STRIPE_HANDLE, &sh->state); |
3691 | clear_bit(STRIPE_DELAYED, &sh->state); | |
1da177e4 | 3692 | release_stripe(sh); |
1da177e4 LT |
3693 | } else { |
3694 | /* cannot get stripe for read-ahead, just give-up */ | |
3695 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
3696 | finish_wait(&conf->wait_for_overlap, &w); | |
3697 | break; | |
3698 | } | |
3699 | ||
3700 | } | |
3701 | spin_lock_irq(&conf->device_lock); | |
960e739d | 3702 | remaining = raid5_dec_bi_phys_segments(bi); |
f6344757 N |
3703 | spin_unlock_irq(&conf->device_lock); |
3704 | if (remaining == 0) { | |
1da177e4 | 3705 | |
16a53ecc | 3706 | if ( rw == WRITE ) |
1da177e4 | 3707 | md_write_end(mddev); |
6712ecf8 | 3708 | |
0e13fe23 | 3709 | bio_endio(bi, 0); |
1da177e4 | 3710 | } |
1da177e4 LT |
3711 | return 0; |
3712 | } | |
3713 | ||
b522adcd DW |
3714 | static sector_t raid5_size(mddev_t *mddev, sector_t sectors, int raid_disks); |
3715 | ||
52c03291 | 3716 | static sector_t reshape_request(mddev_t *mddev, sector_t sector_nr, int *skipped) |
1da177e4 | 3717 | { |
52c03291 N |
3718 | /* reshaping is quite different to recovery/resync so it is |
3719 | * handled quite separately ... here. | |
3720 | * | |
3721 | * On each call to sync_request, we gather one chunk worth of | |
3722 | * destination stripes and flag them as expanding. | |
3723 | * Then we find all the source stripes and request reads. | |
3724 | * As the reads complete, handle_stripe will copy the data | |
3725 | * into the destination stripe and release that stripe. | |
3726 | */ | |
1da177e4 LT |
3727 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; |
3728 | struct stripe_head *sh; | |
ccfcc3c1 | 3729 | sector_t first_sector, last_sector; |
f416885e N |
3730 | int raid_disks = conf->previous_raid_disks; |
3731 | int data_disks = raid_disks - conf->max_degraded; | |
3732 | int new_data_disks = conf->raid_disks - conf->max_degraded; | |
52c03291 N |
3733 | int i; |
3734 | int dd_idx; | |
3735 | sector_t writepos, safepos, gap; | |
ec32a2bd | 3736 | sector_t stripe_addr; |
52c03291 | 3737 | |
fef9c61f N |
3738 | if (sector_nr == 0) { |
3739 | /* If restarting in the middle, skip the initial sectors */ | |
3740 | if (mddev->delta_disks < 0 && | |
3741 | conf->reshape_progress < raid5_size(mddev, 0, 0)) { | |
3742 | sector_nr = raid5_size(mddev, 0, 0) | |
3743 | - conf->reshape_progress; | |
3744 | } else if (mddev->delta_disks > 0 && | |
3745 | conf->reshape_progress > 0) | |
3746 | sector_nr = conf->reshape_progress; | |
f416885e | 3747 | sector_div(sector_nr, new_data_disks); |
fef9c61f N |
3748 | if (sector_nr) { |
3749 | *skipped = 1; | |
3750 | return sector_nr; | |
3751 | } | |
52c03291 N |
3752 | } |
3753 | ||
3754 | /* we update the metadata when there is more than 3Meg | |
3755 | * in the block range (that is rather arbitrary, should | |
3756 | * probably be time based) or when the data about to be | |
3757 | * copied would over-write the source of the data at | |
3758 | * the front of the range. | |
fef9c61f N |
3759 | * i.e. one new_stripe along from reshape_progress new_maps |
3760 | * to after where reshape_safe old_maps to | |
52c03291 | 3761 | */ |
fef9c61f | 3762 | writepos = conf->reshape_progress; |
f416885e | 3763 | sector_div(writepos, new_data_disks); |
fef9c61f | 3764 | safepos = conf->reshape_safe; |
f416885e | 3765 | sector_div(safepos, data_disks); |
fef9c61f N |
3766 | if (mddev->delta_disks < 0) { |
3767 | writepos -= conf->chunk_size/512; | |
3768 | safepos += conf->chunk_size/512; | |
3769 | gap = conf->reshape_safe - conf->reshape_progress; | |
3770 | } else { | |
3771 | writepos += conf->chunk_size/512; | |
3772 | safepos -= conf->chunk_size/512; | |
3773 | gap = conf->reshape_progress - conf->reshape_safe; | |
3774 | } | |
52c03291 | 3775 | |
fef9c61f N |
3776 | if ((mddev->delta_disks < 0 |
3777 | ? writepos < safepos | |
3778 | : writepos > safepos) || | |
f416885e | 3779 | gap > (new_data_disks)*3000*2 /*3Meg*/) { |
52c03291 N |
3780 | /* Cannot proceed until we've updated the superblock... */ |
3781 | wait_event(conf->wait_for_overlap, | |
3782 | atomic_read(&conf->reshape_stripes)==0); | |
fef9c61f | 3783 | mddev->reshape_position = conf->reshape_progress; |
850b2b42 | 3784 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
52c03291 | 3785 | md_wakeup_thread(mddev->thread); |
850b2b42 | 3786 | wait_event(mddev->sb_wait, mddev->flags == 0 || |
52c03291 N |
3787 | kthread_should_stop()); |
3788 | spin_lock_irq(&conf->device_lock); | |
fef9c61f | 3789 | conf->reshape_safe = mddev->reshape_position; |
52c03291 N |
3790 | spin_unlock_irq(&conf->device_lock); |
3791 | wake_up(&conf->wait_for_overlap); | |
3792 | } | |
3793 | ||
ec32a2bd N |
3794 | if (mddev->delta_disks < 0) { |
3795 | BUG_ON(conf->reshape_progress == 0); | |
3796 | stripe_addr = writepos; | |
3797 | BUG_ON((mddev->dev_sectors & | |
784052ec | 3798 | ~((sector_t)conf->chunk_size / 512 - 1)) |
ec32a2bd N |
3799 | - (conf->chunk_size / 512) - stripe_addr |
3800 | != sector_nr); | |
3801 | } else { | |
3802 | BUG_ON(writepos != sector_nr + conf->chunk_size / 512); | |
3803 | stripe_addr = sector_nr; | |
3804 | } | |
52c03291 N |
3805 | for (i=0; i < conf->chunk_size/512; i+= STRIPE_SECTORS) { |
3806 | int j; | |
3807 | int skipped = 0; | |
ec32a2bd | 3808 | sh = get_active_stripe(conf, stripe_addr+i, 0, 0); |
52c03291 N |
3809 | set_bit(STRIPE_EXPANDING, &sh->state); |
3810 | atomic_inc(&conf->reshape_stripes); | |
3811 | /* If any of this stripe is beyond the end of the old | |
3812 | * array, then we need to zero those blocks | |
3813 | */ | |
3814 | for (j=sh->disks; j--;) { | |
3815 | sector_t s; | |
3816 | if (j == sh->pd_idx) | |
3817 | continue; | |
f416885e | 3818 | if (conf->level == 6 && |
d0dabf7e | 3819 | j == sh->qd_idx) |
f416885e | 3820 | continue; |
784052ec | 3821 | s = compute_blocknr(sh, j, 0); |
b522adcd | 3822 | if (s < raid5_size(mddev, 0, 0)) { |
52c03291 N |
3823 | skipped = 1; |
3824 | continue; | |
3825 | } | |
3826 | memset(page_address(sh->dev[j].page), 0, STRIPE_SIZE); | |
3827 | set_bit(R5_Expanded, &sh->dev[j].flags); | |
3828 | set_bit(R5_UPTODATE, &sh->dev[j].flags); | |
3829 | } | |
3830 | if (!skipped) { | |
3831 | set_bit(STRIPE_EXPAND_READY, &sh->state); | |
3832 | set_bit(STRIPE_HANDLE, &sh->state); | |
3833 | } | |
3834 | release_stripe(sh); | |
3835 | } | |
3836 | spin_lock_irq(&conf->device_lock); | |
fef9c61f N |
3837 | if (mddev->delta_disks < 0) |
3838 | conf->reshape_progress -= i * new_data_disks; | |
3839 | else | |
3840 | conf->reshape_progress += i * new_data_disks; | |
52c03291 N |
3841 | spin_unlock_irq(&conf->device_lock); |
3842 | /* Ok, those stripe are ready. We can start scheduling | |
3843 | * reads on the source stripes. | |
3844 | * The source stripes are determined by mapping the first and last | |
3845 | * block on the destination stripes. | |
3846 | */ | |
52c03291 | 3847 | first_sector = |
ec32a2bd | 3848 | raid5_compute_sector(conf, stripe_addr*(new_data_disks), |
911d4ee8 | 3849 | 1, &dd_idx, NULL); |
52c03291 | 3850 | last_sector = |
ec32a2bd | 3851 | raid5_compute_sector(conf, ((stripe_addr+conf->chunk_size/512) |
112bf897 | 3852 | *(new_data_disks) - 1), |
911d4ee8 | 3853 | 1, &dd_idx, NULL); |
58c0fed4 AN |
3854 | if (last_sector >= mddev->dev_sectors) |
3855 | last_sector = mddev->dev_sectors - 1; | |
52c03291 | 3856 | while (first_sector <= last_sector) { |
b5663ba4 | 3857 | sh = get_active_stripe(conf, first_sector, 1, 0); |
52c03291 N |
3858 | set_bit(STRIPE_EXPAND_SOURCE, &sh->state); |
3859 | set_bit(STRIPE_HANDLE, &sh->state); | |
3860 | release_stripe(sh); | |
3861 | first_sector += STRIPE_SECTORS; | |
3862 | } | |
c6207277 N |
3863 | /* If this takes us to the resync_max point where we have to pause, |
3864 | * then we need to write out the superblock. | |
3865 | */ | |
3866 | sector_nr += conf->chunk_size>>9; | |
3867 | if (sector_nr >= mddev->resync_max) { | |
3868 | /* Cannot proceed until we've updated the superblock... */ | |
3869 | wait_event(conf->wait_for_overlap, | |
3870 | atomic_read(&conf->reshape_stripes) == 0); | |
fef9c61f | 3871 | mddev->reshape_position = conf->reshape_progress; |
c6207277 N |
3872 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
3873 | md_wakeup_thread(mddev->thread); | |
3874 | wait_event(mddev->sb_wait, | |
3875 | !test_bit(MD_CHANGE_DEVS, &mddev->flags) | |
3876 | || kthread_should_stop()); | |
3877 | spin_lock_irq(&conf->device_lock); | |
fef9c61f | 3878 | conf->reshape_safe = mddev->reshape_position; |
c6207277 N |
3879 | spin_unlock_irq(&conf->device_lock); |
3880 | wake_up(&conf->wait_for_overlap); | |
3881 | } | |
52c03291 N |
3882 | return conf->chunk_size>>9; |
3883 | } | |
3884 | ||
3885 | /* FIXME go_faster isn't used */ | |
3886 | static inline sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, int go_faster) | |
3887 | { | |
3888 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; | |
3889 | struct stripe_head *sh; | |
58c0fed4 | 3890 | sector_t max_sector = mddev->dev_sectors; |
72626685 | 3891 | int sync_blocks; |
16a53ecc N |
3892 | int still_degraded = 0; |
3893 | int i; | |
1da177e4 | 3894 | |
72626685 | 3895 | if (sector_nr >= max_sector) { |
1da177e4 LT |
3896 | /* just being told to finish up .. nothing much to do */ |
3897 | unplug_slaves(mddev); | |
cea9c228 | 3898 | |
29269553 N |
3899 | if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) { |
3900 | end_reshape(conf); | |
3901 | return 0; | |
3902 | } | |
72626685 N |
3903 | |
3904 | if (mddev->curr_resync < max_sector) /* aborted */ | |
3905 | bitmap_end_sync(mddev->bitmap, mddev->curr_resync, | |
3906 | &sync_blocks, 1); | |
16a53ecc | 3907 | else /* completed sync */ |
72626685 N |
3908 | conf->fullsync = 0; |
3909 | bitmap_close_sync(mddev->bitmap); | |
3910 | ||
1da177e4 LT |
3911 | return 0; |
3912 | } | |
ccfcc3c1 | 3913 | |
52c03291 N |
3914 | if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) |
3915 | return reshape_request(mddev, sector_nr, skipped); | |
f6705578 | 3916 | |
c6207277 N |
3917 | /* No need to check resync_max as we never do more than one |
3918 | * stripe, and as resync_max will always be on a chunk boundary, | |
3919 | * if the check in md_do_sync didn't fire, there is no chance | |
3920 | * of overstepping resync_max here | |
3921 | */ | |
3922 | ||
16a53ecc | 3923 | /* if there is too many failed drives and we are trying |
1da177e4 LT |
3924 | * to resync, then assert that we are finished, because there is |
3925 | * nothing we can do. | |
3926 | */ | |
3285edf1 | 3927 | if (mddev->degraded >= conf->max_degraded && |
16a53ecc | 3928 | test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) { |
58c0fed4 | 3929 | sector_t rv = mddev->dev_sectors - sector_nr; |
57afd89f | 3930 | *skipped = 1; |
1da177e4 LT |
3931 | return rv; |
3932 | } | |
72626685 | 3933 | if (!bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, 1) && |
3855ad9f | 3934 | !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) && |
72626685 N |
3935 | !conf->fullsync && sync_blocks >= STRIPE_SECTORS) { |
3936 | /* we can skip this block, and probably more */ | |
3937 | sync_blocks /= STRIPE_SECTORS; | |
3938 | *skipped = 1; | |
3939 | return sync_blocks * STRIPE_SECTORS; /* keep things rounded to whole stripes */ | |
3940 | } | |
1da177e4 | 3941 | |
b47490c9 N |
3942 | |
3943 | bitmap_cond_end_sync(mddev->bitmap, sector_nr); | |
3944 | ||
b5663ba4 | 3945 | sh = get_active_stripe(conf, sector_nr, 0, 1); |
1da177e4 | 3946 | if (sh == NULL) { |
b5663ba4 | 3947 | sh = get_active_stripe(conf, sector_nr, 0, 0); |
1da177e4 | 3948 | /* make sure we don't swamp the stripe cache if someone else |
16a53ecc | 3949 | * is trying to get access |
1da177e4 | 3950 | */ |
66c006a5 | 3951 | schedule_timeout_uninterruptible(1); |
1da177e4 | 3952 | } |
16a53ecc N |
3953 | /* Need to check if array will still be degraded after recovery/resync |
3954 | * We don't need to check the 'failed' flag as when that gets set, | |
3955 | * recovery aborts. | |
3956 | */ | |
3957 | for (i=0; i<mddev->raid_disks; i++) | |
3958 | if (conf->disks[i].rdev == NULL) | |
3959 | still_degraded = 1; | |
3960 | ||
3961 | bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, still_degraded); | |
3962 | ||
3963 | spin_lock(&sh->lock); | |
1da177e4 LT |
3964 | set_bit(STRIPE_SYNCING, &sh->state); |
3965 | clear_bit(STRIPE_INSYNC, &sh->state); | |
3966 | spin_unlock(&sh->lock); | |
3967 | ||
df10cfbc DW |
3968 | /* wait for any blocked device to be handled */ |
3969 | while(unlikely(!handle_stripe(sh, NULL))) | |
3970 | ; | |
1da177e4 LT |
3971 | release_stripe(sh); |
3972 | ||
3973 | return STRIPE_SECTORS; | |
3974 | } | |
3975 | ||
46031f9a RBJ |
3976 | static int retry_aligned_read(raid5_conf_t *conf, struct bio *raid_bio) |
3977 | { | |
3978 | /* We may not be able to submit a whole bio at once as there | |
3979 | * may not be enough stripe_heads available. | |
3980 | * We cannot pre-allocate enough stripe_heads as we may need | |
3981 | * more than exist in the cache (if we allow ever large chunks). | |
3982 | * So we do one stripe head at a time and record in | |
3983 | * ->bi_hw_segments how many have been done. | |
3984 | * | |
3985 | * We *know* that this entire raid_bio is in one chunk, so | |
3986 | * it will be only one 'dd_idx' and only need one call to raid5_compute_sector. | |
3987 | */ | |
3988 | struct stripe_head *sh; | |
911d4ee8 | 3989 | int dd_idx; |
46031f9a RBJ |
3990 | sector_t sector, logical_sector, last_sector; |
3991 | int scnt = 0; | |
3992 | int remaining; | |
3993 | int handled = 0; | |
3994 | ||
3995 | logical_sector = raid_bio->bi_sector & ~((sector_t)STRIPE_SECTORS-1); | |
112bf897 | 3996 | sector = raid5_compute_sector(conf, logical_sector, |
911d4ee8 | 3997 | 0, &dd_idx, NULL); |
46031f9a RBJ |
3998 | last_sector = raid_bio->bi_sector + (raid_bio->bi_size>>9); |
3999 | ||
4000 | for (; logical_sector < last_sector; | |
387bb173 NB |
4001 | logical_sector += STRIPE_SECTORS, |
4002 | sector += STRIPE_SECTORS, | |
4003 | scnt++) { | |
46031f9a | 4004 | |
960e739d | 4005 | if (scnt < raid5_bi_hw_segments(raid_bio)) |
46031f9a RBJ |
4006 | /* already done this stripe */ |
4007 | continue; | |
4008 | ||
b5663ba4 | 4009 | sh = get_active_stripe(conf, sector, 0, 1); |
46031f9a RBJ |
4010 | |
4011 | if (!sh) { | |
4012 | /* failed to get a stripe - must wait */ | |
960e739d | 4013 | raid5_set_bi_hw_segments(raid_bio, scnt); |
46031f9a RBJ |
4014 | conf->retry_read_aligned = raid_bio; |
4015 | return handled; | |
4016 | } | |
4017 | ||
4018 | set_bit(R5_ReadError, &sh->dev[dd_idx].flags); | |
387bb173 NB |
4019 | if (!add_stripe_bio(sh, raid_bio, dd_idx, 0)) { |
4020 | release_stripe(sh); | |
960e739d | 4021 | raid5_set_bi_hw_segments(raid_bio, scnt); |
387bb173 NB |
4022 | conf->retry_read_aligned = raid_bio; |
4023 | return handled; | |
4024 | } | |
4025 | ||
46031f9a RBJ |
4026 | handle_stripe(sh, NULL); |
4027 | release_stripe(sh); | |
4028 | handled++; | |
4029 | } | |
4030 | spin_lock_irq(&conf->device_lock); | |
960e739d | 4031 | remaining = raid5_dec_bi_phys_segments(raid_bio); |
46031f9a | 4032 | spin_unlock_irq(&conf->device_lock); |
0e13fe23 NB |
4033 | if (remaining == 0) |
4034 | bio_endio(raid_bio, 0); | |
46031f9a RBJ |
4035 | if (atomic_dec_and_test(&conf->active_aligned_reads)) |
4036 | wake_up(&conf->wait_for_stripe); | |
4037 | return handled; | |
4038 | } | |
4039 | ||
4040 | ||
4041 | ||
1da177e4 LT |
4042 | /* |
4043 | * This is our raid5 kernel thread. | |
4044 | * | |
4045 | * We scan the hash table for stripes which can be handled now. | |
4046 | * During the scan, completed stripes are saved for us by the interrupt | |
4047 | * handler, so that they will not have to wait for our next wakeup. | |
4048 | */ | |
6ed3003c | 4049 | static void raid5d(mddev_t *mddev) |
1da177e4 LT |
4050 | { |
4051 | struct stripe_head *sh; | |
4052 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4053 | int handled; | |
4054 | ||
45b4233c | 4055 | pr_debug("+++ raid5d active\n"); |
1da177e4 LT |
4056 | |
4057 | md_check_recovery(mddev); | |
1da177e4 LT |
4058 | |
4059 | handled = 0; | |
4060 | spin_lock_irq(&conf->device_lock); | |
4061 | while (1) { | |
46031f9a | 4062 | struct bio *bio; |
1da177e4 | 4063 | |
ae3c20cc | 4064 | if (conf->seq_flush != conf->seq_write) { |
72626685 | 4065 | int seq = conf->seq_flush; |
700e432d | 4066 | spin_unlock_irq(&conf->device_lock); |
72626685 | 4067 | bitmap_unplug(mddev->bitmap); |
700e432d | 4068 | spin_lock_irq(&conf->device_lock); |
72626685 N |
4069 | conf->seq_write = seq; |
4070 | activate_bit_delay(conf); | |
4071 | } | |
4072 | ||
46031f9a RBJ |
4073 | while ((bio = remove_bio_from_retry(conf))) { |
4074 | int ok; | |
4075 | spin_unlock_irq(&conf->device_lock); | |
4076 | ok = retry_aligned_read(conf, bio); | |
4077 | spin_lock_irq(&conf->device_lock); | |
4078 | if (!ok) | |
4079 | break; | |
4080 | handled++; | |
4081 | } | |
4082 | ||
8b3e6cdc DW |
4083 | sh = __get_priority_stripe(conf); |
4084 | ||
c9f21aaf | 4085 | if (!sh) |
1da177e4 | 4086 | break; |
1da177e4 LT |
4087 | spin_unlock_irq(&conf->device_lock); |
4088 | ||
4089 | handled++; | |
16a53ecc | 4090 | handle_stripe(sh, conf->spare_page); |
1da177e4 LT |
4091 | release_stripe(sh); |
4092 | ||
4093 | spin_lock_irq(&conf->device_lock); | |
4094 | } | |
45b4233c | 4095 | pr_debug("%d stripes handled\n", handled); |
1da177e4 LT |
4096 | |
4097 | spin_unlock_irq(&conf->device_lock); | |
4098 | ||
c9f21aaf | 4099 | async_tx_issue_pending_all(); |
1da177e4 LT |
4100 | unplug_slaves(mddev); |
4101 | ||
45b4233c | 4102 | pr_debug("--- raid5d inactive\n"); |
1da177e4 LT |
4103 | } |
4104 | ||
3f294f4f | 4105 | static ssize_t |
007583c9 | 4106 | raid5_show_stripe_cache_size(mddev_t *mddev, char *page) |
3f294f4f | 4107 | { |
007583c9 | 4108 | raid5_conf_t *conf = mddev_to_conf(mddev); |
96de1e66 N |
4109 | if (conf) |
4110 | return sprintf(page, "%d\n", conf->max_nr_stripes); | |
4111 | else | |
4112 | return 0; | |
3f294f4f N |
4113 | } |
4114 | ||
4115 | static ssize_t | |
007583c9 | 4116 | raid5_store_stripe_cache_size(mddev_t *mddev, const char *page, size_t len) |
3f294f4f | 4117 | { |
007583c9 | 4118 | raid5_conf_t *conf = mddev_to_conf(mddev); |
4ef197d8 | 4119 | unsigned long new; |
b5470dc5 DW |
4120 | int err; |
4121 | ||
3f294f4f N |
4122 | if (len >= PAGE_SIZE) |
4123 | return -EINVAL; | |
96de1e66 N |
4124 | if (!conf) |
4125 | return -ENODEV; | |
3f294f4f | 4126 | |
4ef197d8 | 4127 | if (strict_strtoul(page, 10, &new)) |
3f294f4f N |
4128 | return -EINVAL; |
4129 | if (new <= 16 || new > 32768) | |
4130 | return -EINVAL; | |
4131 | while (new < conf->max_nr_stripes) { | |
4132 | if (drop_one_stripe(conf)) | |
4133 | conf->max_nr_stripes--; | |
4134 | else | |
4135 | break; | |
4136 | } | |
b5470dc5 DW |
4137 | err = md_allow_write(mddev); |
4138 | if (err) | |
4139 | return err; | |
3f294f4f N |
4140 | while (new > conf->max_nr_stripes) { |
4141 | if (grow_one_stripe(conf)) | |
4142 | conf->max_nr_stripes++; | |
4143 | else break; | |
4144 | } | |
4145 | return len; | |
4146 | } | |
007583c9 | 4147 | |
96de1e66 N |
4148 | static struct md_sysfs_entry |
4149 | raid5_stripecache_size = __ATTR(stripe_cache_size, S_IRUGO | S_IWUSR, | |
4150 | raid5_show_stripe_cache_size, | |
4151 | raid5_store_stripe_cache_size); | |
3f294f4f | 4152 | |
8b3e6cdc DW |
4153 | static ssize_t |
4154 | raid5_show_preread_threshold(mddev_t *mddev, char *page) | |
4155 | { | |
4156 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4157 | if (conf) | |
4158 | return sprintf(page, "%d\n", conf->bypass_threshold); | |
4159 | else | |
4160 | return 0; | |
4161 | } | |
4162 | ||
4163 | static ssize_t | |
4164 | raid5_store_preread_threshold(mddev_t *mddev, const char *page, size_t len) | |
4165 | { | |
4166 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4ef197d8 | 4167 | unsigned long new; |
8b3e6cdc DW |
4168 | if (len >= PAGE_SIZE) |
4169 | return -EINVAL; | |
4170 | if (!conf) | |
4171 | return -ENODEV; | |
4172 | ||
4ef197d8 | 4173 | if (strict_strtoul(page, 10, &new)) |
8b3e6cdc | 4174 | return -EINVAL; |
4ef197d8 | 4175 | if (new > conf->max_nr_stripes) |
8b3e6cdc DW |
4176 | return -EINVAL; |
4177 | conf->bypass_threshold = new; | |
4178 | return len; | |
4179 | } | |
4180 | ||
4181 | static struct md_sysfs_entry | |
4182 | raid5_preread_bypass_threshold = __ATTR(preread_bypass_threshold, | |
4183 | S_IRUGO | S_IWUSR, | |
4184 | raid5_show_preread_threshold, | |
4185 | raid5_store_preread_threshold); | |
4186 | ||
3f294f4f | 4187 | static ssize_t |
96de1e66 | 4188 | stripe_cache_active_show(mddev_t *mddev, char *page) |
3f294f4f | 4189 | { |
007583c9 | 4190 | raid5_conf_t *conf = mddev_to_conf(mddev); |
96de1e66 N |
4191 | if (conf) |
4192 | return sprintf(page, "%d\n", atomic_read(&conf->active_stripes)); | |
4193 | else | |
4194 | return 0; | |
3f294f4f N |
4195 | } |
4196 | ||
96de1e66 N |
4197 | static struct md_sysfs_entry |
4198 | raid5_stripecache_active = __ATTR_RO(stripe_cache_active); | |
3f294f4f | 4199 | |
007583c9 | 4200 | static struct attribute *raid5_attrs[] = { |
3f294f4f N |
4201 | &raid5_stripecache_size.attr, |
4202 | &raid5_stripecache_active.attr, | |
8b3e6cdc | 4203 | &raid5_preread_bypass_threshold.attr, |
3f294f4f N |
4204 | NULL, |
4205 | }; | |
007583c9 N |
4206 | static struct attribute_group raid5_attrs_group = { |
4207 | .name = NULL, | |
4208 | .attrs = raid5_attrs, | |
3f294f4f N |
4209 | }; |
4210 | ||
80c3a6ce DW |
4211 | static sector_t |
4212 | raid5_size(mddev_t *mddev, sector_t sectors, int raid_disks) | |
4213 | { | |
4214 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4215 | ||
4216 | if (!sectors) | |
4217 | sectors = mddev->dev_sectors; | |
7ec05478 N |
4218 | if (!raid_disks) { |
4219 | /* size is defined by the smallest of previous and new size */ | |
4220 | if (conf->raid_disks < conf->previous_raid_disks) | |
4221 | raid_disks = conf->raid_disks; | |
4222 | else | |
4223 | raid_disks = conf->previous_raid_disks; | |
4224 | } | |
80c3a6ce DW |
4225 | |
4226 | sectors &= ~((sector_t)mddev->chunk_size/512 - 1); | |
784052ec | 4227 | sectors &= ~((sector_t)mddev->new_chunk/512 - 1); |
80c3a6ce DW |
4228 | return sectors * (raid_disks - conf->max_degraded); |
4229 | } | |
4230 | ||
91adb564 | 4231 | static raid5_conf_t *setup_conf(mddev_t *mddev) |
1da177e4 LT |
4232 | { |
4233 | raid5_conf_t *conf; | |
4234 | int raid_disk, memory; | |
4235 | mdk_rdev_t *rdev; | |
4236 | struct disk_info *disk; | |
1da177e4 | 4237 | |
91adb564 N |
4238 | if (mddev->new_level != 5 |
4239 | && mddev->new_level != 4 | |
4240 | && mddev->new_level != 6) { | |
16a53ecc | 4241 | printk(KERN_ERR "raid5: %s: raid level not set to 4/5/6 (%d)\n", |
91adb564 N |
4242 | mdname(mddev), mddev->new_level); |
4243 | return ERR_PTR(-EIO); | |
1da177e4 | 4244 | } |
91adb564 N |
4245 | if ((mddev->new_level == 5 |
4246 | && !algorithm_valid_raid5(mddev->new_layout)) || | |
4247 | (mddev->new_level == 6 | |
4248 | && !algorithm_valid_raid6(mddev->new_layout))) { | |
99c0fb5f | 4249 | printk(KERN_ERR "raid5: %s: layout %d not supported\n", |
91adb564 N |
4250 | mdname(mddev), mddev->new_layout); |
4251 | return ERR_PTR(-EIO); | |
99c0fb5f | 4252 | } |
91adb564 N |
4253 | if (mddev->new_level == 6 && mddev->raid_disks < 4) { |
4254 | printk(KERN_ERR "raid6: not enough configured devices for %s (%d, minimum 4)\n", | |
4255 | mdname(mddev), mddev->raid_disks); | |
4256 | return ERR_PTR(-EINVAL); | |
4bbf3771 N |
4257 | } |
4258 | ||
91adb564 N |
4259 | if (!mddev->new_chunk || mddev->new_chunk % PAGE_SIZE) { |
4260 | printk(KERN_ERR "raid5: invalid chunk size %d for %s\n", | |
4261 | mddev->new_chunk, mdname(mddev)); | |
4262 | return ERR_PTR(-EINVAL); | |
f6705578 N |
4263 | } |
4264 | ||
91adb564 N |
4265 | conf = kzalloc(sizeof(raid5_conf_t), GFP_KERNEL); |
4266 | if (conf == NULL) | |
1da177e4 | 4267 | goto abort; |
91adb564 N |
4268 | |
4269 | conf->raid_disks = mddev->raid_disks; | |
4270 | if (mddev->reshape_position == MaxSector) | |
4271 | conf->previous_raid_disks = mddev->raid_disks; | |
4272 | else | |
f6705578 | 4273 | conf->previous_raid_disks = mddev->raid_disks - mddev->delta_disks; |
f6705578 N |
4274 | |
4275 | conf->disks = kzalloc(conf->raid_disks * sizeof(struct disk_info), | |
b55e6bfc N |
4276 | GFP_KERNEL); |
4277 | if (!conf->disks) | |
4278 | goto abort; | |
9ffae0cf | 4279 | |
1da177e4 LT |
4280 | conf->mddev = mddev; |
4281 | ||
fccddba0 | 4282 | if ((conf->stripe_hashtbl = kzalloc(PAGE_SIZE, GFP_KERNEL)) == NULL) |
1da177e4 | 4283 | goto abort; |
1da177e4 | 4284 | |
91adb564 | 4285 | if (mddev->new_level == 6) { |
16a53ecc N |
4286 | conf->spare_page = alloc_page(GFP_KERNEL); |
4287 | if (!conf->spare_page) | |
4288 | goto abort; | |
4289 | } | |
1da177e4 LT |
4290 | spin_lock_init(&conf->device_lock); |
4291 | init_waitqueue_head(&conf->wait_for_stripe); | |
4292 | init_waitqueue_head(&conf->wait_for_overlap); | |
4293 | INIT_LIST_HEAD(&conf->handle_list); | |
8b3e6cdc | 4294 | INIT_LIST_HEAD(&conf->hold_list); |
1da177e4 | 4295 | INIT_LIST_HEAD(&conf->delayed_list); |
72626685 | 4296 | INIT_LIST_HEAD(&conf->bitmap_list); |
1da177e4 LT |
4297 | INIT_LIST_HEAD(&conf->inactive_list); |
4298 | atomic_set(&conf->active_stripes, 0); | |
4299 | atomic_set(&conf->preread_active_stripes, 0); | |
46031f9a | 4300 | atomic_set(&conf->active_aligned_reads, 0); |
8b3e6cdc | 4301 | conf->bypass_threshold = BYPASS_THRESHOLD; |
1da177e4 | 4302 | |
45b4233c | 4303 | pr_debug("raid5: run(%s) called.\n", mdname(mddev)); |
1da177e4 | 4304 | |
159ec1fc | 4305 | list_for_each_entry(rdev, &mddev->disks, same_set) { |
1da177e4 | 4306 | raid_disk = rdev->raid_disk; |
f6705578 | 4307 | if (raid_disk >= conf->raid_disks |
1da177e4 LT |
4308 | || raid_disk < 0) |
4309 | continue; | |
4310 | disk = conf->disks + raid_disk; | |
4311 | ||
4312 | disk->rdev = rdev; | |
4313 | ||
b2d444d7 | 4314 | if (test_bit(In_sync, &rdev->flags)) { |
1da177e4 LT |
4315 | char b[BDEVNAME_SIZE]; |
4316 | printk(KERN_INFO "raid5: device %s operational as raid" | |
4317 | " disk %d\n", bdevname(rdev->bdev,b), | |
4318 | raid_disk); | |
8c2e870a NB |
4319 | } else |
4320 | /* Cannot rely on bitmap to complete recovery */ | |
4321 | conf->fullsync = 1; | |
1da177e4 LT |
4322 | } |
4323 | ||
91adb564 N |
4324 | conf->chunk_size = mddev->new_chunk; |
4325 | conf->level = mddev->new_level; | |
16a53ecc N |
4326 | if (conf->level == 6) |
4327 | conf->max_degraded = 2; | |
4328 | else | |
4329 | conf->max_degraded = 1; | |
91adb564 | 4330 | conf->algorithm = mddev->new_layout; |
1da177e4 | 4331 | conf->max_nr_stripes = NR_STRIPES; |
fef9c61f | 4332 | conf->reshape_progress = mddev->reshape_position; |
784052ec N |
4333 | if (conf->reshape_progress != MaxSector) |
4334 | conf->prev_chunk = mddev->chunk_size; | |
1da177e4 | 4335 | |
91adb564 N |
4336 | memory = conf->max_nr_stripes * (sizeof(struct stripe_head) + |
4337 | conf->raid_disks * ((sizeof(struct bio) + PAGE_SIZE))) / 1024; | |
4338 | if (grow_stripes(conf, conf->max_nr_stripes)) { | |
4339 | printk(KERN_ERR | |
4340 | "raid5: couldn't allocate %dkB for buffers\n", memory); | |
4341 | goto abort; | |
4342 | } else | |
4343 | printk(KERN_INFO "raid5: allocated %dkB for %s\n", | |
4344 | memory, mdname(mddev)); | |
1da177e4 | 4345 | |
91adb564 N |
4346 | conf->thread = md_register_thread(raid5d, mddev, "%s_raid5"); |
4347 | if (!conf->thread) { | |
4348 | printk(KERN_ERR | |
4349 | "raid5: couldn't allocate thread for %s\n", | |
4350 | mdname(mddev)); | |
16a53ecc N |
4351 | goto abort; |
4352 | } | |
91adb564 N |
4353 | |
4354 | return conf; | |
4355 | ||
4356 | abort: | |
4357 | if (conf) { | |
4358 | shrink_stripes(conf); | |
4359 | safe_put_page(conf->spare_page); | |
4360 | kfree(conf->disks); | |
4361 | kfree(conf->stripe_hashtbl); | |
4362 | kfree(conf); | |
4363 | return ERR_PTR(-EIO); | |
4364 | } else | |
4365 | return ERR_PTR(-ENOMEM); | |
4366 | } | |
4367 | ||
4368 | static int run(mddev_t *mddev) | |
4369 | { | |
4370 | raid5_conf_t *conf; | |
4371 | int working_disks = 0; | |
4372 | mdk_rdev_t *rdev; | |
4373 | ||
4374 | if (mddev->reshape_position != MaxSector) { | |
4375 | /* Check that we can continue the reshape. | |
4376 | * Currently only disks can change, it must | |
4377 | * increase, and we must be past the point where | |
4378 | * a stripe over-writes itself | |
4379 | */ | |
4380 | sector_t here_new, here_old; | |
4381 | int old_disks; | |
18b00334 | 4382 | int max_degraded = (mddev->level == 6 ? 2 : 1); |
91adb564 N |
4383 | |
4384 | if (mddev->new_level != mddev->level || | |
4385 | mddev->new_layout != mddev->layout || | |
4386 | mddev->new_chunk != mddev->chunk_size) { | |
4387 | printk(KERN_ERR "raid5: %s: unsupported reshape " | |
4388 | "required - aborting.\n", | |
4389 | mdname(mddev)); | |
4390 | return -EINVAL; | |
4391 | } | |
91adb564 N |
4392 | old_disks = mddev->raid_disks - mddev->delta_disks; |
4393 | /* reshape_position must be on a new-stripe boundary, and one | |
4394 | * further up in new geometry must map after here in old | |
4395 | * geometry. | |
4396 | */ | |
4397 | here_new = mddev->reshape_position; | |
784052ec | 4398 | if (sector_div(here_new, (mddev->new_chunk>>9)* |
91adb564 N |
4399 | (mddev->raid_disks - max_degraded))) { |
4400 | printk(KERN_ERR "raid5: reshape_position not " | |
4401 | "on a stripe boundary\n"); | |
4402 | return -EINVAL; | |
4403 | } | |
4404 | /* here_new is the stripe we will write to */ | |
4405 | here_old = mddev->reshape_position; | |
4406 | sector_div(here_old, (mddev->chunk_size>>9)* | |
4407 | (old_disks-max_degraded)); | |
4408 | /* here_old is the first stripe that we might need to read | |
4409 | * from */ | |
4410 | if (here_new >= here_old) { | |
4411 | /* Reading from the same stripe as writing to - bad */ | |
4412 | printk(KERN_ERR "raid5: reshape_position too early for " | |
4413 | "auto-recovery - aborting.\n"); | |
4414 | return -EINVAL; | |
4415 | } | |
4416 | printk(KERN_INFO "raid5: reshape will continue\n"); | |
4417 | /* OK, we should be able to continue; */ | |
4418 | } else { | |
4419 | BUG_ON(mddev->level != mddev->new_level); | |
4420 | BUG_ON(mddev->layout != mddev->new_layout); | |
4421 | BUG_ON(mddev->chunk_size != mddev->new_chunk); | |
4422 | BUG_ON(mddev->delta_disks != 0); | |
1da177e4 | 4423 | } |
91adb564 | 4424 | |
245f46c2 N |
4425 | if (mddev->private == NULL) |
4426 | conf = setup_conf(mddev); | |
4427 | else | |
4428 | conf = mddev->private; | |
4429 | ||
91adb564 N |
4430 | if (IS_ERR(conf)) |
4431 | return PTR_ERR(conf); | |
4432 | ||
4433 | mddev->thread = conf->thread; | |
4434 | conf->thread = NULL; | |
4435 | mddev->private = conf; | |
4436 | ||
4437 | /* | |
4438 | * 0 for a fully functional array, 1 or 2 for a degraded array. | |
4439 | */ | |
4440 | list_for_each_entry(rdev, &mddev->disks, same_set) | |
4441 | if (rdev->raid_disk >= 0 && | |
4442 | test_bit(In_sync, &rdev->flags)) | |
4443 | working_disks++; | |
4444 | ||
4445 | mddev->degraded = conf->raid_disks - working_disks; | |
4446 | ||
16a53ecc | 4447 | if (mddev->degraded > conf->max_degraded) { |
1da177e4 LT |
4448 | printk(KERN_ERR "raid5: not enough operational devices for %s" |
4449 | " (%d/%d failed)\n", | |
02c2de8c | 4450 | mdname(mddev), mddev->degraded, conf->raid_disks); |
1da177e4 LT |
4451 | goto abort; |
4452 | } | |
4453 | ||
91adb564 N |
4454 | /* device size must be a multiple of chunk size */ |
4455 | mddev->dev_sectors &= ~(mddev->chunk_size / 512 - 1); | |
4456 | mddev->resync_max_sectors = mddev->dev_sectors; | |
4457 | ||
16a53ecc | 4458 | if (mddev->degraded > 0 && |
1da177e4 | 4459 | mddev->recovery_cp != MaxSector) { |
6ff8d8ec N |
4460 | if (mddev->ok_start_degraded) |
4461 | printk(KERN_WARNING | |
4462 | "raid5: starting dirty degraded array: %s" | |
4463 | "- data corruption possible.\n", | |
4464 | mdname(mddev)); | |
4465 | else { | |
4466 | printk(KERN_ERR | |
4467 | "raid5: cannot start dirty degraded array for %s\n", | |
4468 | mdname(mddev)); | |
4469 | goto abort; | |
4470 | } | |
1da177e4 LT |
4471 | } |
4472 | ||
1da177e4 LT |
4473 | if (mddev->degraded == 0) |
4474 | printk("raid5: raid level %d set %s active with %d out of %d" | |
4475 | " devices, algorithm %d\n", conf->level, mdname(mddev), | |
4476 | mddev->raid_disks-mddev->degraded, mddev->raid_disks, | |
4477 | conf->algorithm); | |
4478 | else | |
4479 | printk(KERN_ALERT "raid5: raid level %d set %s active with %d" | |
4480 | " out of %d devices, algorithm %d\n", conf->level, | |
4481 | mdname(mddev), mddev->raid_disks - mddev->degraded, | |
4482 | mddev->raid_disks, conf->algorithm); | |
4483 | ||
4484 | print_raid5_conf(conf); | |
4485 | ||
fef9c61f | 4486 | if (conf->reshape_progress != MaxSector) { |
f6705578 | 4487 | printk("...ok start reshape thread\n"); |
fef9c61f | 4488 | conf->reshape_safe = conf->reshape_progress; |
f6705578 N |
4489 | atomic_set(&conf->reshape_stripes, 0); |
4490 | clear_bit(MD_RECOVERY_SYNC, &mddev->recovery); | |
4491 | clear_bit(MD_RECOVERY_CHECK, &mddev->recovery); | |
4492 | set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery); | |
4493 | set_bit(MD_RECOVERY_RUNNING, &mddev->recovery); | |
4494 | mddev->sync_thread = md_register_thread(md_do_sync, mddev, | |
4495 | "%s_reshape"); | |
f6705578 N |
4496 | } |
4497 | ||
1da177e4 | 4498 | /* read-ahead size must cover two whole stripes, which is |
16a53ecc | 4499 | * 2 * (datadisks) * chunksize where 'n' is the number of raid devices |
1da177e4 LT |
4500 | */ |
4501 | { | |
16a53ecc N |
4502 | int data_disks = conf->previous_raid_disks - conf->max_degraded; |
4503 | int stripe = data_disks * | |
8932c2e0 | 4504 | (mddev->chunk_size / PAGE_SIZE); |
1da177e4 LT |
4505 | if (mddev->queue->backing_dev_info.ra_pages < 2 * stripe) |
4506 | mddev->queue->backing_dev_info.ra_pages = 2 * stripe; | |
4507 | } | |
4508 | ||
4509 | /* Ok, everything is just fine now */ | |
5e55e2f5 N |
4510 | if (sysfs_create_group(&mddev->kobj, &raid5_attrs_group)) |
4511 | printk(KERN_WARNING | |
4512 | "raid5: failed to create sysfs attributes for %s\n", | |
4513 | mdname(mddev)); | |
7a5febe9 | 4514 | |
91adb564 N |
4515 | mddev->queue->queue_lock = &conf->device_lock; |
4516 | ||
7a5febe9 | 4517 | mddev->queue->unplug_fn = raid5_unplug_device; |
f022b2fd | 4518 | mddev->queue->backing_dev_info.congested_data = mddev; |
041ae52e | 4519 | mddev->queue->backing_dev_info.congested_fn = raid5_congested; |
f022b2fd | 4520 | |
1f403624 | 4521 | md_set_array_sectors(mddev, raid5_size(mddev, 0, 0)); |
7a5febe9 | 4522 | |
23032a0e RBJ |
4523 | blk_queue_merge_bvec(mddev->queue, raid5_mergeable_bvec); |
4524 | ||
1da177e4 LT |
4525 | return 0; |
4526 | abort: | |
e0cf8f04 | 4527 | md_unregister_thread(mddev->thread); |
91adb564 | 4528 | mddev->thread = NULL; |
1da177e4 | 4529 | if (conf) { |
91adb564 | 4530 | shrink_stripes(conf); |
1da177e4 | 4531 | print_raid5_conf(conf); |
16a53ecc | 4532 | safe_put_page(conf->spare_page); |
b55e6bfc | 4533 | kfree(conf->disks); |
fccddba0 | 4534 | kfree(conf->stripe_hashtbl); |
1da177e4 LT |
4535 | kfree(conf); |
4536 | } | |
4537 | mddev->private = NULL; | |
4538 | printk(KERN_ALERT "raid5: failed to run raid set %s\n", mdname(mddev)); | |
4539 | return -EIO; | |
4540 | } | |
4541 | ||
4542 | ||
4543 | ||
3f294f4f | 4544 | static int stop(mddev_t *mddev) |
1da177e4 LT |
4545 | { |
4546 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; | |
4547 | ||
4548 | md_unregister_thread(mddev->thread); | |
4549 | mddev->thread = NULL; | |
4550 | shrink_stripes(conf); | |
fccddba0 | 4551 | kfree(conf->stripe_hashtbl); |
041ae52e | 4552 | mddev->queue->backing_dev_info.congested_fn = NULL; |
1da177e4 | 4553 | blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/ |
007583c9 | 4554 | sysfs_remove_group(&mddev->kobj, &raid5_attrs_group); |
b55e6bfc | 4555 | kfree(conf->disks); |
96de1e66 | 4556 | kfree(conf); |
1da177e4 LT |
4557 | mddev->private = NULL; |
4558 | return 0; | |
4559 | } | |
4560 | ||
45b4233c | 4561 | #ifdef DEBUG |
d710e138 | 4562 | static void print_sh(struct seq_file *seq, struct stripe_head *sh) |
1da177e4 LT |
4563 | { |
4564 | int i; | |
4565 | ||
16a53ecc N |
4566 | seq_printf(seq, "sh %llu, pd_idx %d, state %ld.\n", |
4567 | (unsigned long long)sh->sector, sh->pd_idx, sh->state); | |
4568 | seq_printf(seq, "sh %llu, count %d.\n", | |
4569 | (unsigned long long)sh->sector, atomic_read(&sh->count)); | |
4570 | seq_printf(seq, "sh %llu, ", (unsigned long long)sh->sector); | |
7ecaa1e6 | 4571 | for (i = 0; i < sh->disks; i++) { |
16a53ecc N |
4572 | seq_printf(seq, "(cache%d: %p %ld) ", |
4573 | i, sh->dev[i].page, sh->dev[i].flags); | |
1da177e4 | 4574 | } |
16a53ecc | 4575 | seq_printf(seq, "\n"); |
1da177e4 LT |
4576 | } |
4577 | ||
d710e138 | 4578 | static void printall(struct seq_file *seq, raid5_conf_t *conf) |
1da177e4 LT |
4579 | { |
4580 | struct stripe_head *sh; | |
fccddba0 | 4581 | struct hlist_node *hn; |
1da177e4 LT |
4582 | int i; |
4583 | ||
4584 | spin_lock_irq(&conf->device_lock); | |
4585 | for (i = 0; i < NR_HASH; i++) { | |
fccddba0 | 4586 | hlist_for_each_entry(sh, hn, &conf->stripe_hashtbl[i], hash) { |
1da177e4 LT |
4587 | if (sh->raid_conf != conf) |
4588 | continue; | |
16a53ecc | 4589 | print_sh(seq, sh); |
1da177e4 LT |
4590 | } |
4591 | } | |
4592 | spin_unlock_irq(&conf->device_lock); | |
4593 | } | |
4594 | #endif | |
4595 | ||
d710e138 | 4596 | static void status(struct seq_file *seq, mddev_t *mddev) |
1da177e4 LT |
4597 | { |
4598 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; | |
4599 | int i; | |
4600 | ||
4601 | seq_printf (seq, " level %d, %dk chunk, algorithm %d", mddev->level, mddev->chunk_size >> 10, mddev->layout); | |
02c2de8c | 4602 | seq_printf (seq, " [%d/%d] [", conf->raid_disks, conf->raid_disks - mddev->degraded); |
1da177e4 LT |
4603 | for (i = 0; i < conf->raid_disks; i++) |
4604 | seq_printf (seq, "%s", | |
4605 | conf->disks[i].rdev && | |
b2d444d7 | 4606 | test_bit(In_sync, &conf->disks[i].rdev->flags) ? "U" : "_"); |
1da177e4 | 4607 | seq_printf (seq, "]"); |
45b4233c | 4608 | #ifdef DEBUG |
16a53ecc N |
4609 | seq_printf (seq, "\n"); |
4610 | printall(seq, conf); | |
1da177e4 LT |
4611 | #endif |
4612 | } | |
4613 | ||
4614 | static void print_raid5_conf (raid5_conf_t *conf) | |
4615 | { | |
4616 | int i; | |
4617 | struct disk_info *tmp; | |
4618 | ||
4619 | printk("RAID5 conf printout:\n"); | |
4620 | if (!conf) { | |
4621 | printk("(conf==NULL)\n"); | |
4622 | return; | |
4623 | } | |
02c2de8c N |
4624 | printk(" --- rd:%d wd:%d\n", conf->raid_disks, |
4625 | conf->raid_disks - conf->mddev->degraded); | |
1da177e4 LT |
4626 | |
4627 | for (i = 0; i < conf->raid_disks; i++) { | |
4628 | char b[BDEVNAME_SIZE]; | |
4629 | tmp = conf->disks + i; | |
4630 | if (tmp->rdev) | |
4631 | printk(" disk %d, o:%d, dev:%s\n", | |
b2d444d7 | 4632 | i, !test_bit(Faulty, &tmp->rdev->flags), |
1da177e4 LT |
4633 | bdevname(tmp->rdev->bdev,b)); |
4634 | } | |
4635 | } | |
4636 | ||
4637 | static int raid5_spare_active(mddev_t *mddev) | |
4638 | { | |
4639 | int i; | |
4640 | raid5_conf_t *conf = mddev->private; | |
4641 | struct disk_info *tmp; | |
4642 | ||
4643 | for (i = 0; i < conf->raid_disks; i++) { | |
4644 | tmp = conf->disks + i; | |
4645 | if (tmp->rdev | |
b2d444d7 | 4646 | && !test_bit(Faulty, &tmp->rdev->flags) |
c04be0aa N |
4647 | && !test_and_set_bit(In_sync, &tmp->rdev->flags)) { |
4648 | unsigned long flags; | |
4649 | spin_lock_irqsave(&conf->device_lock, flags); | |
1da177e4 | 4650 | mddev->degraded--; |
c04be0aa | 4651 | spin_unlock_irqrestore(&conf->device_lock, flags); |
1da177e4 LT |
4652 | } |
4653 | } | |
4654 | print_raid5_conf(conf); | |
4655 | return 0; | |
4656 | } | |
4657 | ||
4658 | static int raid5_remove_disk(mddev_t *mddev, int number) | |
4659 | { | |
4660 | raid5_conf_t *conf = mddev->private; | |
4661 | int err = 0; | |
4662 | mdk_rdev_t *rdev; | |
4663 | struct disk_info *p = conf->disks + number; | |
4664 | ||
4665 | print_raid5_conf(conf); | |
4666 | rdev = p->rdev; | |
4667 | if (rdev) { | |
ec32a2bd N |
4668 | if (number >= conf->raid_disks && |
4669 | conf->reshape_progress == MaxSector) | |
4670 | clear_bit(In_sync, &rdev->flags); | |
4671 | ||
b2d444d7 | 4672 | if (test_bit(In_sync, &rdev->flags) || |
1da177e4 LT |
4673 | atomic_read(&rdev->nr_pending)) { |
4674 | err = -EBUSY; | |
4675 | goto abort; | |
4676 | } | |
dfc70645 N |
4677 | /* Only remove non-faulty devices if recovery |
4678 | * isn't possible. | |
4679 | */ | |
4680 | if (!test_bit(Faulty, &rdev->flags) && | |
ec32a2bd N |
4681 | mddev->degraded <= conf->max_degraded && |
4682 | number < conf->raid_disks) { | |
dfc70645 N |
4683 | err = -EBUSY; |
4684 | goto abort; | |
4685 | } | |
1da177e4 | 4686 | p->rdev = NULL; |
fbd568a3 | 4687 | synchronize_rcu(); |
1da177e4 LT |
4688 | if (atomic_read(&rdev->nr_pending)) { |
4689 | /* lost the race, try later */ | |
4690 | err = -EBUSY; | |
4691 | p->rdev = rdev; | |
4692 | } | |
4693 | } | |
4694 | abort: | |
4695 | ||
4696 | print_raid5_conf(conf); | |
4697 | return err; | |
4698 | } | |
4699 | ||
4700 | static int raid5_add_disk(mddev_t *mddev, mdk_rdev_t *rdev) | |
4701 | { | |
4702 | raid5_conf_t *conf = mddev->private; | |
199050ea | 4703 | int err = -EEXIST; |
1da177e4 LT |
4704 | int disk; |
4705 | struct disk_info *p; | |
6c2fce2e NB |
4706 | int first = 0; |
4707 | int last = conf->raid_disks - 1; | |
1da177e4 | 4708 | |
16a53ecc | 4709 | if (mddev->degraded > conf->max_degraded) |
1da177e4 | 4710 | /* no point adding a device */ |
199050ea | 4711 | return -EINVAL; |
1da177e4 | 4712 | |
6c2fce2e NB |
4713 | if (rdev->raid_disk >= 0) |
4714 | first = last = rdev->raid_disk; | |
1da177e4 LT |
4715 | |
4716 | /* | |
16a53ecc N |
4717 | * find the disk ... but prefer rdev->saved_raid_disk |
4718 | * if possible. | |
1da177e4 | 4719 | */ |
16a53ecc | 4720 | if (rdev->saved_raid_disk >= 0 && |
6c2fce2e | 4721 | rdev->saved_raid_disk >= first && |
16a53ecc N |
4722 | conf->disks[rdev->saved_raid_disk].rdev == NULL) |
4723 | disk = rdev->saved_raid_disk; | |
4724 | else | |
6c2fce2e NB |
4725 | disk = first; |
4726 | for ( ; disk <= last ; disk++) | |
1da177e4 | 4727 | if ((p=conf->disks + disk)->rdev == NULL) { |
b2d444d7 | 4728 | clear_bit(In_sync, &rdev->flags); |
1da177e4 | 4729 | rdev->raid_disk = disk; |
199050ea | 4730 | err = 0; |
72626685 N |
4731 | if (rdev->saved_raid_disk != disk) |
4732 | conf->fullsync = 1; | |
d6065f7b | 4733 | rcu_assign_pointer(p->rdev, rdev); |
1da177e4 LT |
4734 | break; |
4735 | } | |
4736 | print_raid5_conf(conf); | |
199050ea | 4737 | return err; |
1da177e4 LT |
4738 | } |
4739 | ||
4740 | static int raid5_resize(mddev_t *mddev, sector_t sectors) | |
4741 | { | |
4742 | /* no resync is happening, and there is enough space | |
4743 | * on all devices, so we can resize. | |
4744 | * We need to make sure resync covers any new space. | |
4745 | * If the array is shrinking we should possibly wait until | |
4746 | * any io in the removed space completes, but it hardly seems | |
4747 | * worth it. | |
4748 | */ | |
4749 | sectors &= ~((sector_t)mddev->chunk_size/512 - 1); | |
1f403624 DW |
4750 | md_set_array_sectors(mddev, raid5_size(mddev, sectors, |
4751 | mddev->raid_disks)); | |
b522adcd DW |
4752 | if (mddev->array_sectors > |
4753 | raid5_size(mddev, sectors, mddev->raid_disks)) | |
4754 | return -EINVAL; | |
f233ea5c | 4755 | set_capacity(mddev->gendisk, mddev->array_sectors); |
44ce6294 | 4756 | mddev->changed = 1; |
58c0fed4 AN |
4757 | if (sectors > mddev->dev_sectors && mddev->recovery_cp == MaxSector) { |
4758 | mddev->recovery_cp = mddev->dev_sectors; | |
1da177e4 LT |
4759 | set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); |
4760 | } | |
58c0fed4 | 4761 | mddev->dev_sectors = sectors; |
4b5c7ae8 | 4762 | mddev->resync_max_sectors = sectors; |
1da177e4 LT |
4763 | return 0; |
4764 | } | |
4765 | ||
29269553 | 4766 | #ifdef CONFIG_MD_RAID5_RESHAPE |
63c70c4f | 4767 | static int raid5_check_reshape(mddev_t *mddev) |
29269553 N |
4768 | { |
4769 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
29269553 | 4770 | |
63c70c4f | 4771 | if (mddev->delta_disks == 0) |
29269553 | 4772 | return 0; /* nothing to do */ |
dba034ee N |
4773 | if (mddev->bitmap) |
4774 | /* Cannot grow a bitmap yet */ | |
4775 | return -EBUSY; | |
ec32a2bd N |
4776 | if (mddev->degraded > conf->max_degraded) |
4777 | return -EINVAL; | |
4778 | if (mddev->delta_disks < 0) { | |
4779 | /* We might be able to shrink, but the devices must | |
4780 | * be made bigger first. | |
4781 | * For raid6, 4 is the minimum size. | |
4782 | * Otherwise 2 is the minimum | |
4783 | */ | |
4784 | int min = 2; | |
4785 | if (mddev->level == 6) | |
4786 | min = 4; | |
4787 | if (mddev->raid_disks + mddev->delta_disks < min) | |
4788 | return -EINVAL; | |
4789 | } | |
29269553 N |
4790 | |
4791 | /* Can only proceed if there are plenty of stripe_heads. | |
4792 | * We need a minimum of one full stripe,, and for sensible progress | |
4793 | * it is best to have about 4 times that. | |
4794 | * If we require 4 times, then the default 256 4K stripe_heads will | |
4795 | * allow for chunk sizes up to 256K, which is probably OK. | |
4796 | * If the chunk size is greater, user-space should request more | |
4797 | * stripe_heads first. | |
4798 | */ | |
63c70c4f N |
4799 | if ((mddev->chunk_size / STRIPE_SIZE) * 4 > conf->max_nr_stripes || |
4800 | (mddev->new_chunk / STRIPE_SIZE) * 4 > conf->max_nr_stripes) { | |
29269553 | 4801 | printk(KERN_WARNING "raid5: reshape: not enough stripes. Needed %lu\n", |
784052ec N |
4802 | (max(mddev->chunk_size, mddev->new_chunk) |
4803 | / STRIPE_SIZE)*4); | |
29269553 N |
4804 | return -ENOSPC; |
4805 | } | |
4806 | ||
ec32a2bd | 4807 | return resize_stripes(conf, conf->raid_disks + mddev->delta_disks); |
63c70c4f N |
4808 | } |
4809 | ||
4810 | static int raid5_start_reshape(mddev_t *mddev) | |
4811 | { | |
4812 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4813 | mdk_rdev_t *rdev; | |
63c70c4f N |
4814 | int spares = 0; |
4815 | int added_devices = 0; | |
c04be0aa | 4816 | unsigned long flags; |
63c70c4f | 4817 | |
f416885e | 4818 | if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) |
63c70c4f N |
4819 | return -EBUSY; |
4820 | ||
159ec1fc | 4821 | list_for_each_entry(rdev, &mddev->disks, same_set) |
29269553 N |
4822 | if (rdev->raid_disk < 0 && |
4823 | !test_bit(Faulty, &rdev->flags)) | |
4824 | spares++; | |
63c70c4f | 4825 | |
f416885e | 4826 | if (spares - mddev->degraded < mddev->delta_disks - conf->max_degraded) |
29269553 N |
4827 | /* Not enough devices even to make a degraded array |
4828 | * of that size | |
4829 | */ | |
4830 | return -EINVAL; | |
4831 | ||
ec32a2bd N |
4832 | /* Refuse to reduce size of the array. Any reductions in |
4833 | * array size must be through explicit setting of array_size | |
4834 | * attribute. | |
4835 | */ | |
4836 | if (raid5_size(mddev, 0, conf->raid_disks + mddev->delta_disks) | |
4837 | < mddev->array_sectors) { | |
4838 | printk(KERN_ERR "md: %s: array size must be reduced " | |
4839 | "before number of disks\n", mdname(mddev)); | |
4840 | return -EINVAL; | |
4841 | } | |
4842 | ||
f6705578 | 4843 | atomic_set(&conf->reshape_stripes, 0); |
29269553 N |
4844 | spin_lock_irq(&conf->device_lock); |
4845 | conf->previous_raid_disks = conf->raid_disks; | |
63c70c4f | 4846 | conf->raid_disks += mddev->delta_disks; |
fef9c61f N |
4847 | if (mddev->delta_disks < 0) |
4848 | conf->reshape_progress = raid5_size(mddev, 0, 0); | |
4849 | else | |
4850 | conf->reshape_progress = 0; | |
4851 | conf->reshape_safe = conf->reshape_progress; | |
86b42c71 | 4852 | conf->generation++; |
29269553 N |
4853 | spin_unlock_irq(&conf->device_lock); |
4854 | ||
4855 | /* Add some new drives, as many as will fit. | |
4856 | * We know there are enough to make the newly sized array work. | |
4857 | */ | |
159ec1fc | 4858 | list_for_each_entry(rdev, &mddev->disks, same_set) |
29269553 N |
4859 | if (rdev->raid_disk < 0 && |
4860 | !test_bit(Faulty, &rdev->flags)) { | |
199050ea | 4861 | if (raid5_add_disk(mddev, rdev) == 0) { |
29269553 N |
4862 | char nm[20]; |
4863 | set_bit(In_sync, &rdev->flags); | |
29269553 | 4864 | added_devices++; |
5fd6c1dc | 4865 | rdev->recovery_offset = 0; |
29269553 | 4866 | sprintf(nm, "rd%d", rdev->raid_disk); |
5e55e2f5 N |
4867 | if (sysfs_create_link(&mddev->kobj, |
4868 | &rdev->kobj, nm)) | |
4869 | printk(KERN_WARNING | |
4870 | "raid5: failed to create " | |
4871 | " link %s for %s\n", | |
4872 | nm, mdname(mddev)); | |
29269553 N |
4873 | } else |
4874 | break; | |
4875 | } | |
4876 | ||
ec32a2bd N |
4877 | if (mddev->delta_disks > 0) { |
4878 | spin_lock_irqsave(&conf->device_lock, flags); | |
4879 | mddev->degraded = (conf->raid_disks - conf->previous_raid_disks) | |
4880 | - added_devices; | |
4881 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
4882 | } | |
63c70c4f | 4883 | mddev->raid_disks = conf->raid_disks; |
f6705578 | 4884 | mddev->reshape_position = 0; |
850b2b42 | 4885 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
f6705578 | 4886 | |
29269553 N |
4887 | clear_bit(MD_RECOVERY_SYNC, &mddev->recovery); |
4888 | clear_bit(MD_RECOVERY_CHECK, &mddev->recovery); | |
4889 | set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery); | |
4890 | set_bit(MD_RECOVERY_RUNNING, &mddev->recovery); | |
4891 | mddev->sync_thread = md_register_thread(md_do_sync, mddev, | |
4892 | "%s_reshape"); | |
4893 | if (!mddev->sync_thread) { | |
4894 | mddev->recovery = 0; | |
4895 | spin_lock_irq(&conf->device_lock); | |
4896 | mddev->raid_disks = conf->raid_disks = conf->previous_raid_disks; | |
fef9c61f | 4897 | conf->reshape_progress = MaxSector; |
29269553 N |
4898 | spin_unlock_irq(&conf->device_lock); |
4899 | return -EAGAIN; | |
4900 | } | |
4901 | md_wakeup_thread(mddev->sync_thread); | |
4902 | md_new_event(mddev); | |
4903 | return 0; | |
4904 | } | |
4905 | #endif | |
4906 | ||
ec32a2bd N |
4907 | /* This is called from the reshape thread and should make any |
4908 | * changes needed in 'conf' | |
4909 | */ | |
29269553 N |
4910 | static void end_reshape(raid5_conf_t *conf) |
4911 | { | |
29269553 | 4912 | |
f6705578 | 4913 | if (!test_bit(MD_RECOVERY_INTR, &conf->mddev->recovery)) { |
f6705578 | 4914 | |
f6705578 | 4915 | spin_lock_irq(&conf->device_lock); |
cea9c228 | 4916 | conf->previous_raid_disks = conf->raid_disks; |
fef9c61f | 4917 | conf->reshape_progress = MaxSector; |
f6705578 | 4918 | spin_unlock_irq(&conf->device_lock); |
16a53ecc N |
4919 | |
4920 | /* read-ahead size must cover two whole stripes, which is | |
4921 | * 2 * (datadisks) * chunksize where 'n' is the number of raid devices | |
4922 | */ | |
4923 | { | |
cea9c228 N |
4924 | int data_disks = conf->raid_disks - conf->max_degraded; |
4925 | int stripe = data_disks * (conf->chunk_size | |
4926 | / PAGE_SIZE); | |
16a53ecc N |
4927 | if (conf->mddev->queue->backing_dev_info.ra_pages < 2 * stripe) |
4928 | conf->mddev->queue->backing_dev_info.ra_pages = 2 * stripe; | |
4929 | } | |
29269553 | 4930 | } |
29269553 N |
4931 | } |
4932 | ||
ec32a2bd N |
4933 | /* This is called from the raid5d thread with mddev_lock held. |
4934 | * It makes config changes to the device. | |
4935 | */ | |
cea9c228 N |
4936 | static void raid5_finish_reshape(mddev_t *mddev) |
4937 | { | |
4938 | struct block_device *bdev; | |
4939 | ||
4940 | if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery)) { | |
4941 | ||
ec32a2bd N |
4942 | if (mddev->delta_disks > 0) { |
4943 | md_set_array_sectors(mddev, raid5_size(mddev, 0, 0)); | |
4944 | set_capacity(mddev->gendisk, mddev->array_sectors); | |
4945 | mddev->changed = 1; | |
4946 | ||
4947 | bdev = bdget_disk(mddev->gendisk, 0); | |
4948 | if (bdev) { | |
4949 | mutex_lock(&bdev->bd_inode->i_mutex); | |
4950 | i_size_write(bdev->bd_inode, | |
4951 | (loff_t)mddev->array_sectors << 9); | |
4952 | mutex_unlock(&bdev->bd_inode->i_mutex); | |
4953 | bdput(bdev); | |
4954 | } | |
4955 | } else { | |
4956 | int d; | |
4957 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4958 | mddev->degraded = conf->raid_disks; | |
4959 | for (d = 0; d < conf->raid_disks ; d++) | |
4960 | if (conf->disks[d].rdev && | |
4961 | test_bit(In_sync, | |
4962 | &conf->disks[d].rdev->flags)) | |
4963 | mddev->degraded--; | |
4964 | for (d = conf->raid_disks ; | |
4965 | d < conf->raid_disks - mddev->delta_disks; | |
4966 | d++) | |
4967 | raid5_remove_disk(mddev, d); | |
cea9c228 | 4968 | } |
ec32a2bd N |
4969 | mddev->reshape_position = MaxSector; |
4970 | mddev->delta_disks = 0; | |
cea9c228 N |
4971 | } |
4972 | } | |
4973 | ||
72626685 N |
4974 | static void raid5_quiesce(mddev_t *mddev, int state) |
4975 | { | |
4976 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4977 | ||
4978 | switch(state) { | |
e464eafd N |
4979 | case 2: /* resume for a suspend */ |
4980 | wake_up(&conf->wait_for_overlap); | |
4981 | break; | |
4982 | ||
72626685 N |
4983 | case 1: /* stop all writes */ |
4984 | spin_lock_irq(&conf->device_lock); | |
4985 | conf->quiesce = 1; | |
4986 | wait_event_lock_irq(conf->wait_for_stripe, | |
46031f9a RBJ |
4987 | atomic_read(&conf->active_stripes) == 0 && |
4988 | atomic_read(&conf->active_aligned_reads) == 0, | |
72626685 N |
4989 | conf->device_lock, /* nothing */); |
4990 | spin_unlock_irq(&conf->device_lock); | |
4991 | break; | |
4992 | ||
4993 | case 0: /* re-enable writes */ | |
4994 | spin_lock_irq(&conf->device_lock); | |
4995 | conf->quiesce = 0; | |
4996 | wake_up(&conf->wait_for_stripe); | |
e464eafd | 4997 | wake_up(&conf->wait_for_overlap); |
72626685 N |
4998 | spin_unlock_irq(&conf->device_lock); |
4999 | break; | |
5000 | } | |
72626685 | 5001 | } |
b15c2e57 | 5002 | |
d562b0c4 N |
5003 | |
5004 | static void *raid5_takeover_raid1(mddev_t *mddev) | |
5005 | { | |
5006 | int chunksect; | |
5007 | ||
5008 | if (mddev->raid_disks != 2 || | |
5009 | mddev->degraded > 1) | |
5010 | return ERR_PTR(-EINVAL); | |
5011 | ||
5012 | /* Should check if there are write-behind devices? */ | |
5013 | ||
5014 | chunksect = 64*2; /* 64K by default */ | |
5015 | ||
5016 | /* The array must be an exact multiple of chunksize */ | |
5017 | while (chunksect && (mddev->array_sectors & (chunksect-1))) | |
5018 | chunksect >>= 1; | |
5019 | ||
5020 | if ((chunksect<<9) < STRIPE_SIZE) | |
5021 | /* array size does not allow a suitable chunk size */ | |
5022 | return ERR_PTR(-EINVAL); | |
5023 | ||
5024 | mddev->new_level = 5; | |
5025 | mddev->new_layout = ALGORITHM_LEFT_SYMMETRIC; | |
5026 | mddev->new_chunk = chunksect << 9; | |
5027 | ||
5028 | return setup_conf(mddev); | |
5029 | } | |
5030 | ||
fc9739c6 N |
5031 | static void *raid5_takeover_raid6(mddev_t *mddev) |
5032 | { | |
5033 | int new_layout; | |
5034 | ||
5035 | switch (mddev->layout) { | |
5036 | case ALGORITHM_LEFT_ASYMMETRIC_6: | |
5037 | new_layout = ALGORITHM_LEFT_ASYMMETRIC; | |
5038 | break; | |
5039 | case ALGORITHM_RIGHT_ASYMMETRIC_6: | |
5040 | new_layout = ALGORITHM_RIGHT_ASYMMETRIC; | |
5041 | break; | |
5042 | case ALGORITHM_LEFT_SYMMETRIC_6: | |
5043 | new_layout = ALGORITHM_LEFT_SYMMETRIC; | |
5044 | break; | |
5045 | case ALGORITHM_RIGHT_SYMMETRIC_6: | |
5046 | new_layout = ALGORITHM_RIGHT_SYMMETRIC; | |
5047 | break; | |
5048 | case ALGORITHM_PARITY_0_6: | |
5049 | new_layout = ALGORITHM_PARITY_0; | |
5050 | break; | |
5051 | case ALGORITHM_PARITY_N: | |
5052 | new_layout = ALGORITHM_PARITY_N; | |
5053 | break; | |
5054 | default: | |
5055 | return ERR_PTR(-EINVAL); | |
5056 | } | |
5057 | mddev->new_level = 5; | |
5058 | mddev->new_layout = new_layout; | |
5059 | mddev->delta_disks = -1; | |
5060 | mddev->raid_disks -= 1; | |
5061 | return setup_conf(mddev); | |
5062 | } | |
5063 | ||
d562b0c4 | 5064 | |
b3546035 N |
5065 | static int raid5_reconfig(mddev_t *mddev, int new_layout, int new_chunk) |
5066 | { | |
5067 | /* Currently the layout and chunk size can only be changed | |
5068 | * for a 2-drive raid array, as in that case no data shuffling | |
5069 | * is required. | |
5070 | * Later we might validate these and set new_* so a reshape | |
5071 | * can complete the change. | |
5072 | */ | |
5073 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
5074 | ||
5075 | if (new_layout >= 0 && !algorithm_valid_raid5(new_layout)) | |
5076 | return -EINVAL; | |
5077 | if (new_chunk > 0) { | |
5078 | if (new_chunk & (new_chunk-1)) | |
5079 | /* not a power of 2 */ | |
5080 | return -EINVAL; | |
5081 | if (new_chunk < PAGE_SIZE) | |
5082 | return -EINVAL; | |
5083 | if (mddev->array_sectors & ((new_chunk>>9)-1)) | |
5084 | /* not factor of array size */ | |
5085 | return -EINVAL; | |
5086 | } | |
5087 | ||
5088 | /* They look valid */ | |
5089 | ||
5090 | if (mddev->raid_disks != 2) | |
5091 | return -EINVAL; | |
5092 | ||
5093 | if (new_layout >= 0) { | |
5094 | conf->algorithm = new_layout; | |
5095 | mddev->layout = mddev->new_layout = new_layout; | |
5096 | } | |
5097 | if (new_chunk > 0) { | |
5098 | conf->chunk_size = new_chunk; | |
5099 | mddev->chunk_size = mddev->new_chunk = new_chunk; | |
5100 | } | |
5101 | set_bit(MD_CHANGE_DEVS, &mddev->flags); | |
5102 | md_wakeup_thread(mddev->thread); | |
5103 | return 0; | |
5104 | } | |
5105 | ||
d562b0c4 N |
5106 | static void *raid5_takeover(mddev_t *mddev) |
5107 | { | |
5108 | /* raid5 can take over: | |
5109 | * raid0 - if all devices are the same - make it a raid4 layout | |
5110 | * raid1 - if there are two drives. We need to know the chunk size | |
5111 | * raid4 - trivial - just use a raid4 layout. | |
5112 | * raid6 - Providing it is a *_6 layout | |
5113 | * | |
5114 | * For now, just do raid1 | |
5115 | */ | |
5116 | ||
5117 | if (mddev->level == 1) | |
5118 | return raid5_takeover_raid1(mddev); | |
e9d4758f N |
5119 | if (mddev->level == 4) { |
5120 | mddev->new_layout = ALGORITHM_PARITY_N; | |
5121 | mddev->new_level = 5; | |
5122 | return setup_conf(mddev); | |
5123 | } | |
fc9739c6 N |
5124 | if (mddev->level == 6) |
5125 | return raid5_takeover_raid6(mddev); | |
d562b0c4 N |
5126 | |
5127 | return ERR_PTR(-EINVAL); | |
5128 | } | |
5129 | ||
5130 | ||
245f46c2 N |
5131 | static struct mdk_personality raid5_personality; |
5132 | ||
5133 | static void *raid6_takeover(mddev_t *mddev) | |
5134 | { | |
5135 | /* Currently can only take over a raid5. We map the | |
5136 | * personality to an equivalent raid6 personality | |
5137 | * with the Q block at the end. | |
5138 | */ | |
5139 | int new_layout; | |
5140 | ||
5141 | if (mddev->pers != &raid5_personality) | |
5142 | return ERR_PTR(-EINVAL); | |
5143 | if (mddev->degraded > 1) | |
5144 | return ERR_PTR(-EINVAL); | |
5145 | if (mddev->raid_disks > 253) | |
5146 | return ERR_PTR(-EINVAL); | |
5147 | if (mddev->raid_disks < 3) | |
5148 | return ERR_PTR(-EINVAL); | |
5149 | ||
5150 | switch (mddev->layout) { | |
5151 | case ALGORITHM_LEFT_ASYMMETRIC: | |
5152 | new_layout = ALGORITHM_LEFT_ASYMMETRIC_6; | |
5153 | break; | |
5154 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
5155 | new_layout = ALGORITHM_RIGHT_ASYMMETRIC_6; | |
5156 | break; | |
5157 | case ALGORITHM_LEFT_SYMMETRIC: | |
5158 | new_layout = ALGORITHM_LEFT_SYMMETRIC_6; | |
5159 | break; | |
5160 | case ALGORITHM_RIGHT_SYMMETRIC: | |
5161 | new_layout = ALGORITHM_RIGHT_SYMMETRIC_6; | |
5162 | break; | |
5163 | case ALGORITHM_PARITY_0: | |
5164 | new_layout = ALGORITHM_PARITY_0_6; | |
5165 | break; | |
5166 | case ALGORITHM_PARITY_N: | |
5167 | new_layout = ALGORITHM_PARITY_N; | |
5168 | break; | |
5169 | default: | |
5170 | return ERR_PTR(-EINVAL); | |
5171 | } | |
5172 | mddev->new_level = 6; | |
5173 | mddev->new_layout = new_layout; | |
5174 | mddev->delta_disks = 1; | |
5175 | mddev->raid_disks += 1; | |
5176 | return setup_conf(mddev); | |
5177 | } | |
5178 | ||
5179 | ||
16a53ecc N |
5180 | static struct mdk_personality raid6_personality = |
5181 | { | |
5182 | .name = "raid6", | |
5183 | .level = 6, | |
5184 | .owner = THIS_MODULE, | |
5185 | .make_request = make_request, | |
5186 | .run = run, | |
5187 | .stop = stop, | |
5188 | .status = status, | |
5189 | .error_handler = error, | |
5190 | .hot_add_disk = raid5_add_disk, | |
5191 | .hot_remove_disk= raid5_remove_disk, | |
5192 | .spare_active = raid5_spare_active, | |
5193 | .sync_request = sync_request, | |
5194 | .resize = raid5_resize, | |
80c3a6ce | 5195 | .size = raid5_size, |
f416885e N |
5196 | #ifdef CONFIG_MD_RAID5_RESHAPE |
5197 | .check_reshape = raid5_check_reshape, | |
5198 | .start_reshape = raid5_start_reshape, | |
cea9c228 | 5199 | .finish_reshape = raid5_finish_reshape, |
f416885e | 5200 | #endif |
16a53ecc | 5201 | .quiesce = raid5_quiesce, |
245f46c2 | 5202 | .takeover = raid6_takeover, |
16a53ecc | 5203 | }; |
2604b703 | 5204 | static struct mdk_personality raid5_personality = |
1da177e4 LT |
5205 | { |
5206 | .name = "raid5", | |
2604b703 | 5207 | .level = 5, |
1da177e4 LT |
5208 | .owner = THIS_MODULE, |
5209 | .make_request = make_request, | |
5210 | .run = run, | |
5211 | .stop = stop, | |
5212 | .status = status, | |
5213 | .error_handler = error, | |
5214 | .hot_add_disk = raid5_add_disk, | |
5215 | .hot_remove_disk= raid5_remove_disk, | |
5216 | .spare_active = raid5_spare_active, | |
5217 | .sync_request = sync_request, | |
5218 | .resize = raid5_resize, | |
80c3a6ce | 5219 | .size = raid5_size, |
29269553 | 5220 | #ifdef CONFIG_MD_RAID5_RESHAPE |
63c70c4f N |
5221 | .check_reshape = raid5_check_reshape, |
5222 | .start_reshape = raid5_start_reshape, | |
cea9c228 | 5223 | .finish_reshape = raid5_finish_reshape, |
29269553 | 5224 | #endif |
72626685 | 5225 | .quiesce = raid5_quiesce, |
d562b0c4 | 5226 | .takeover = raid5_takeover, |
b3546035 | 5227 | .reconfig = raid5_reconfig, |
1da177e4 LT |
5228 | }; |
5229 | ||
2604b703 | 5230 | static struct mdk_personality raid4_personality = |
1da177e4 | 5231 | { |
2604b703 N |
5232 | .name = "raid4", |
5233 | .level = 4, | |
5234 | .owner = THIS_MODULE, | |
5235 | .make_request = make_request, | |
5236 | .run = run, | |
5237 | .stop = stop, | |
5238 | .status = status, | |
5239 | .error_handler = error, | |
5240 | .hot_add_disk = raid5_add_disk, | |
5241 | .hot_remove_disk= raid5_remove_disk, | |
5242 | .spare_active = raid5_spare_active, | |
5243 | .sync_request = sync_request, | |
5244 | .resize = raid5_resize, | |
80c3a6ce | 5245 | .size = raid5_size, |
3d37890b N |
5246 | #ifdef CONFIG_MD_RAID5_RESHAPE |
5247 | .check_reshape = raid5_check_reshape, | |
5248 | .start_reshape = raid5_start_reshape, | |
cea9c228 | 5249 | .finish_reshape = raid5_finish_reshape, |
3d37890b | 5250 | #endif |
2604b703 N |
5251 | .quiesce = raid5_quiesce, |
5252 | }; | |
5253 | ||
5254 | static int __init raid5_init(void) | |
5255 | { | |
16a53ecc | 5256 | register_md_personality(&raid6_personality); |
2604b703 N |
5257 | register_md_personality(&raid5_personality); |
5258 | register_md_personality(&raid4_personality); | |
5259 | return 0; | |
1da177e4 LT |
5260 | } |
5261 | ||
2604b703 | 5262 | static void raid5_exit(void) |
1da177e4 | 5263 | { |
16a53ecc | 5264 | unregister_md_personality(&raid6_personality); |
2604b703 N |
5265 | unregister_md_personality(&raid5_personality); |
5266 | unregister_md_personality(&raid4_personality); | |
1da177e4 LT |
5267 | } |
5268 | ||
5269 | module_init(raid5_init); | |
5270 | module_exit(raid5_exit); | |
5271 | MODULE_LICENSE("GPL"); | |
5272 | MODULE_ALIAS("md-personality-4"); /* RAID5 */ | |
d9d166c2 N |
5273 | MODULE_ALIAS("md-raid5"); |
5274 | MODULE_ALIAS("md-raid4"); | |
2604b703 N |
5275 | MODULE_ALIAS("md-level-5"); |
5276 | MODULE_ALIAS("md-level-4"); | |
16a53ecc N |
5277 | MODULE_ALIAS("md-personality-8"); /* RAID6 */ |
5278 | MODULE_ALIAS("md-raid6"); | |
5279 | MODULE_ALIAS("md-level-6"); | |
5280 | ||
5281 | /* This used to be two separate modules, they were: */ | |
5282 | MODULE_ALIAS("raid5"); | |
5283 | MODULE_ALIAS("raid6"); |