Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * raid5.c : Multiple Devices driver for Linux | |
3 | * Copyright (C) 1996, 1997 Ingo Molnar, Miguel de Icaza, Gadi Oxman | |
4 | * Copyright (C) 1999, 2000 Ingo Molnar | |
16a53ecc | 5 | * Copyright (C) 2002, 2003 H. Peter Anvin |
1da177e4 | 6 | * |
16a53ecc N |
7 | * RAID-4/5/6 management functions. |
8 | * Thanks to Penguin Computing for making the RAID-6 development possible | |
9 | * by donating a test server! | |
1da177e4 LT |
10 | * |
11 | * This program is free software; you can redistribute it and/or modify | |
12 | * it under the terms of the GNU General Public License as published by | |
13 | * the Free Software Foundation; either version 2, or (at your option) | |
14 | * any later version. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License | |
17 | * (for example /usr/src/linux/COPYING); if not, write to the Free | |
18 | * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | |
19 | */ | |
20 | ||
ae3c20cc N |
21 | /* |
22 | * BITMAP UNPLUGGING: | |
23 | * | |
24 | * The sequencing for updating the bitmap reliably is a little | |
25 | * subtle (and I got it wrong the first time) so it deserves some | |
26 | * explanation. | |
27 | * | |
28 | * We group bitmap updates into batches. Each batch has a number. | |
29 | * We may write out several batches at once, but that isn't very important. | |
30 | * conf->bm_write is the number of the last batch successfully written. | |
31 | * conf->bm_flush is the number of the last batch that was closed to | |
32 | * new additions. | |
33 | * When we discover that we will need to write to any block in a stripe | |
34 | * (in add_stripe_bio) we update the in-memory bitmap and record in sh->bm_seq | |
35 | * the number of the batch it will be in. This is bm_flush+1. | |
36 | * When we are ready to do a write, if that batch hasn't been written yet, | |
37 | * we plug the array and queue the stripe for later. | |
38 | * When an unplug happens, we increment bm_flush, thus closing the current | |
39 | * batch. | |
40 | * When we notice that bm_flush > bm_write, we write out all pending updates | |
41 | * to the bitmap, and advance bm_write to where bm_flush was. | |
42 | * This may occasionally write a bit out twice, but is sure never to | |
43 | * miss any bits. | |
44 | */ | |
1da177e4 | 45 | |
1da177e4 LT |
46 | #include <linux/module.h> |
47 | #include <linux/slab.h> | |
1da177e4 LT |
48 | #include <linux/highmem.h> |
49 | #include <linux/bitops.h> | |
f6705578 | 50 | #include <linux/kthread.h> |
1da177e4 | 51 | #include <asm/atomic.h> |
16a53ecc | 52 | #include "raid6.h" |
1da177e4 | 53 | |
72626685 | 54 | #include <linux/raid/bitmap.h> |
91c00924 | 55 | #include <linux/async_tx.h> |
72626685 | 56 | |
1da177e4 LT |
57 | /* |
58 | * Stripe cache | |
59 | */ | |
60 | ||
61 | #define NR_STRIPES 256 | |
62 | #define STRIPE_SIZE PAGE_SIZE | |
63 | #define STRIPE_SHIFT (PAGE_SHIFT - 9) | |
64 | #define STRIPE_SECTORS (STRIPE_SIZE>>9) | |
65 | #define IO_THRESHOLD 1 | |
8b3e6cdc | 66 | #define BYPASS_THRESHOLD 1 |
fccddba0 | 67 | #define NR_HASH (PAGE_SIZE / sizeof(struct hlist_head)) |
1da177e4 LT |
68 | #define HASH_MASK (NR_HASH - 1) |
69 | ||
fccddba0 | 70 | #define stripe_hash(conf, sect) (&((conf)->stripe_hashtbl[((sect) >> STRIPE_SHIFT) & HASH_MASK])) |
1da177e4 LT |
71 | |
72 | /* bio's attached to a stripe+device for I/O are linked together in bi_sector | |
73 | * order without overlap. There may be several bio's per stripe+device, and | |
74 | * a bio could span several devices. | |
75 | * When walking this list for a particular stripe+device, we must never proceed | |
76 | * beyond a bio that extends past this device, as the next bio might no longer | |
77 | * be valid. | |
78 | * This macro is used to determine the 'next' bio in the list, given the sector | |
79 | * of the current stripe+device | |
80 | */ | |
81 | #define r5_next_bio(bio, sect) ( ( (bio)->bi_sector + ((bio)->bi_size>>9) < sect + STRIPE_SECTORS) ? (bio)->bi_next : NULL) | |
82 | /* | |
83 | * The following can be used to debug the driver | |
84 | */ | |
1da177e4 LT |
85 | #define RAID5_PARANOIA 1 |
86 | #if RAID5_PARANOIA && defined(CONFIG_SMP) | |
87 | # define CHECK_DEVLOCK() assert_spin_locked(&conf->device_lock) | |
88 | #else | |
89 | # define CHECK_DEVLOCK() | |
90 | #endif | |
91 | ||
45b4233c | 92 | #ifdef DEBUG |
1da177e4 LT |
93 | #define inline |
94 | #define __inline__ | |
95 | #endif | |
96 | ||
6be9d494 BS |
97 | #define printk_rl(args...) ((void) (printk_ratelimit() && printk(args))) |
98 | ||
16a53ecc N |
99 | #if !RAID6_USE_EMPTY_ZERO_PAGE |
100 | /* In .bss so it's zeroed */ | |
101 | const char raid6_empty_zero_page[PAGE_SIZE] __attribute__((aligned(256))); | |
102 | #endif | |
103 | ||
104 | static inline int raid6_next_disk(int disk, int raid_disks) | |
105 | { | |
106 | disk++; | |
107 | return (disk < raid_disks) ? disk : 0; | |
108 | } | |
a4456856 DW |
109 | |
110 | static void return_io(struct bio *return_bi) | |
111 | { | |
112 | struct bio *bi = return_bi; | |
113 | while (bi) { | |
a4456856 DW |
114 | |
115 | return_bi = bi->bi_next; | |
116 | bi->bi_next = NULL; | |
117 | bi->bi_size = 0; | |
0e13fe23 | 118 | bio_endio(bi, 0); |
a4456856 DW |
119 | bi = return_bi; |
120 | } | |
121 | } | |
122 | ||
1da177e4 LT |
123 | static void print_raid5_conf (raid5_conf_t *conf); |
124 | ||
600aa109 DW |
125 | static int stripe_operations_active(struct stripe_head *sh) |
126 | { | |
127 | return sh->check_state || sh->reconstruct_state || | |
128 | test_bit(STRIPE_BIOFILL_RUN, &sh->state) || | |
129 | test_bit(STRIPE_COMPUTE_RUN, &sh->state); | |
130 | } | |
131 | ||
858119e1 | 132 | static void __release_stripe(raid5_conf_t *conf, struct stripe_head *sh) |
1da177e4 LT |
133 | { |
134 | if (atomic_dec_and_test(&sh->count)) { | |
78bafebd ES |
135 | BUG_ON(!list_empty(&sh->lru)); |
136 | BUG_ON(atomic_read(&conf->active_stripes)==0); | |
1da177e4 | 137 | if (test_bit(STRIPE_HANDLE, &sh->state)) { |
7c785b7a | 138 | if (test_bit(STRIPE_DELAYED, &sh->state)) { |
1da177e4 | 139 | list_add_tail(&sh->lru, &conf->delayed_list); |
7c785b7a N |
140 | blk_plug_device(conf->mddev->queue); |
141 | } else if (test_bit(STRIPE_BIT_DELAY, &sh->state) && | |
ae3c20cc | 142 | sh->bm_seq - conf->seq_write > 0) { |
72626685 | 143 | list_add_tail(&sh->lru, &conf->bitmap_list); |
7c785b7a N |
144 | blk_plug_device(conf->mddev->queue); |
145 | } else { | |
72626685 | 146 | clear_bit(STRIPE_BIT_DELAY, &sh->state); |
1da177e4 | 147 | list_add_tail(&sh->lru, &conf->handle_list); |
72626685 | 148 | } |
1da177e4 LT |
149 | md_wakeup_thread(conf->mddev->thread); |
150 | } else { | |
600aa109 | 151 | BUG_ON(stripe_operations_active(sh)); |
1da177e4 LT |
152 | if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { |
153 | atomic_dec(&conf->preread_active_stripes); | |
154 | if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD) | |
155 | md_wakeup_thread(conf->mddev->thread); | |
156 | } | |
1da177e4 | 157 | atomic_dec(&conf->active_stripes); |
ccfcc3c1 N |
158 | if (!test_bit(STRIPE_EXPANDING, &sh->state)) { |
159 | list_add_tail(&sh->lru, &conf->inactive_list); | |
1da177e4 | 160 | wake_up(&conf->wait_for_stripe); |
46031f9a RBJ |
161 | if (conf->retry_read_aligned) |
162 | md_wakeup_thread(conf->mddev->thread); | |
ccfcc3c1 | 163 | } |
1da177e4 LT |
164 | } |
165 | } | |
166 | } | |
167 | static void release_stripe(struct stripe_head *sh) | |
168 | { | |
169 | raid5_conf_t *conf = sh->raid_conf; | |
170 | unsigned long flags; | |
16a53ecc | 171 | |
1da177e4 LT |
172 | spin_lock_irqsave(&conf->device_lock, flags); |
173 | __release_stripe(conf, sh); | |
174 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
175 | } | |
176 | ||
fccddba0 | 177 | static inline void remove_hash(struct stripe_head *sh) |
1da177e4 | 178 | { |
45b4233c DW |
179 | pr_debug("remove_hash(), stripe %llu\n", |
180 | (unsigned long long)sh->sector); | |
1da177e4 | 181 | |
fccddba0 | 182 | hlist_del_init(&sh->hash); |
1da177e4 LT |
183 | } |
184 | ||
16a53ecc | 185 | static inline void insert_hash(raid5_conf_t *conf, struct stripe_head *sh) |
1da177e4 | 186 | { |
fccddba0 | 187 | struct hlist_head *hp = stripe_hash(conf, sh->sector); |
1da177e4 | 188 | |
45b4233c DW |
189 | pr_debug("insert_hash(), stripe %llu\n", |
190 | (unsigned long long)sh->sector); | |
1da177e4 LT |
191 | |
192 | CHECK_DEVLOCK(); | |
fccddba0 | 193 | hlist_add_head(&sh->hash, hp); |
1da177e4 LT |
194 | } |
195 | ||
196 | ||
197 | /* find an idle stripe, make sure it is unhashed, and return it. */ | |
198 | static struct stripe_head *get_free_stripe(raid5_conf_t *conf) | |
199 | { | |
200 | struct stripe_head *sh = NULL; | |
201 | struct list_head *first; | |
202 | ||
203 | CHECK_DEVLOCK(); | |
204 | if (list_empty(&conf->inactive_list)) | |
205 | goto out; | |
206 | first = conf->inactive_list.next; | |
207 | sh = list_entry(first, struct stripe_head, lru); | |
208 | list_del_init(first); | |
209 | remove_hash(sh); | |
210 | atomic_inc(&conf->active_stripes); | |
211 | out: | |
212 | return sh; | |
213 | } | |
214 | ||
215 | static void shrink_buffers(struct stripe_head *sh, int num) | |
216 | { | |
217 | struct page *p; | |
218 | int i; | |
219 | ||
220 | for (i=0; i<num ; i++) { | |
221 | p = sh->dev[i].page; | |
222 | if (!p) | |
223 | continue; | |
224 | sh->dev[i].page = NULL; | |
2d1f3b5d | 225 | put_page(p); |
1da177e4 LT |
226 | } |
227 | } | |
228 | ||
229 | static int grow_buffers(struct stripe_head *sh, int num) | |
230 | { | |
231 | int i; | |
232 | ||
233 | for (i=0; i<num; i++) { | |
234 | struct page *page; | |
235 | ||
236 | if (!(page = alloc_page(GFP_KERNEL))) { | |
237 | return 1; | |
238 | } | |
239 | sh->dev[i].page = page; | |
240 | } | |
241 | return 0; | |
242 | } | |
243 | ||
244 | static void raid5_build_block (struct stripe_head *sh, int i); | |
245 | ||
7ecaa1e6 | 246 | static void init_stripe(struct stripe_head *sh, sector_t sector, int pd_idx, int disks) |
1da177e4 LT |
247 | { |
248 | raid5_conf_t *conf = sh->raid_conf; | |
7ecaa1e6 | 249 | int i; |
1da177e4 | 250 | |
78bafebd ES |
251 | BUG_ON(atomic_read(&sh->count) != 0); |
252 | BUG_ON(test_bit(STRIPE_HANDLE, &sh->state)); | |
600aa109 | 253 | BUG_ON(stripe_operations_active(sh)); |
d84e0f10 | 254 | |
1da177e4 | 255 | CHECK_DEVLOCK(); |
45b4233c | 256 | pr_debug("init_stripe called, stripe %llu\n", |
1da177e4 LT |
257 | (unsigned long long)sh->sector); |
258 | ||
259 | remove_hash(sh); | |
16a53ecc | 260 | |
1da177e4 LT |
261 | sh->sector = sector; |
262 | sh->pd_idx = pd_idx; | |
263 | sh->state = 0; | |
264 | ||
7ecaa1e6 N |
265 | sh->disks = disks; |
266 | ||
267 | for (i = sh->disks; i--; ) { | |
1da177e4 LT |
268 | struct r5dev *dev = &sh->dev[i]; |
269 | ||
d84e0f10 | 270 | if (dev->toread || dev->read || dev->towrite || dev->written || |
1da177e4 | 271 | test_bit(R5_LOCKED, &dev->flags)) { |
d84e0f10 | 272 | printk(KERN_ERR "sector=%llx i=%d %p %p %p %p %d\n", |
1da177e4 | 273 | (unsigned long long)sh->sector, i, dev->toread, |
d84e0f10 | 274 | dev->read, dev->towrite, dev->written, |
1da177e4 LT |
275 | test_bit(R5_LOCKED, &dev->flags)); |
276 | BUG(); | |
277 | } | |
278 | dev->flags = 0; | |
279 | raid5_build_block(sh, i); | |
280 | } | |
281 | insert_hash(conf, sh); | |
282 | } | |
283 | ||
7ecaa1e6 | 284 | static struct stripe_head *__find_stripe(raid5_conf_t *conf, sector_t sector, int disks) |
1da177e4 LT |
285 | { |
286 | struct stripe_head *sh; | |
fccddba0 | 287 | struct hlist_node *hn; |
1da177e4 LT |
288 | |
289 | CHECK_DEVLOCK(); | |
45b4233c | 290 | pr_debug("__find_stripe, sector %llu\n", (unsigned long long)sector); |
fccddba0 | 291 | hlist_for_each_entry(sh, hn, stripe_hash(conf, sector), hash) |
7ecaa1e6 | 292 | if (sh->sector == sector && sh->disks == disks) |
1da177e4 | 293 | return sh; |
45b4233c | 294 | pr_debug("__stripe %llu not in cache\n", (unsigned long long)sector); |
1da177e4 LT |
295 | return NULL; |
296 | } | |
297 | ||
298 | static void unplug_slaves(mddev_t *mddev); | |
165125e1 | 299 | static void raid5_unplug_device(struct request_queue *q); |
1da177e4 | 300 | |
7ecaa1e6 N |
301 | static struct stripe_head *get_active_stripe(raid5_conf_t *conf, sector_t sector, int disks, |
302 | int pd_idx, int noblock) | |
1da177e4 LT |
303 | { |
304 | struct stripe_head *sh; | |
305 | ||
45b4233c | 306 | pr_debug("get_stripe, sector %llu\n", (unsigned long long)sector); |
1da177e4 LT |
307 | |
308 | spin_lock_irq(&conf->device_lock); | |
309 | ||
310 | do { | |
72626685 N |
311 | wait_event_lock_irq(conf->wait_for_stripe, |
312 | conf->quiesce == 0, | |
313 | conf->device_lock, /* nothing */); | |
7ecaa1e6 | 314 | sh = __find_stripe(conf, sector, disks); |
1da177e4 LT |
315 | if (!sh) { |
316 | if (!conf->inactive_blocked) | |
317 | sh = get_free_stripe(conf); | |
318 | if (noblock && sh == NULL) | |
319 | break; | |
320 | if (!sh) { | |
321 | conf->inactive_blocked = 1; | |
322 | wait_event_lock_irq(conf->wait_for_stripe, | |
323 | !list_empty(&conf->inactive_list) && | |
5036805b N |
324 | (atomic_read(&conf->active_stripes) |
325 | < (conf->max_nr_stripes *3/4) | |
1da177e4 LT |
326 | || !conf->inactive_blocked), |
327 | conf->device_lock, | |
f4370781 | 328 | raid5_unplug_device(conf->mddev->queue) |
1da177e4 LT |
329 | ); |
330 | conf->inactive_blocked = 0; | |
331 | } else | |
7ecaa1e6 | 332 | init_stripe(sh, sector, pd_idx, disks); |
1da177e4 LT |
333 | } else { |
334 | if (atomic_read(&sh->count)) { | |
78bafebd | 335 | BUG_ON(!list_empty(&sh->lru)); |
1da177e4 LT |
336 | } else { |
337 | if (!test_bit(STRIPE_HANDLE, &sh->state)) | |
338 | atomic_inc(&conf->active_stripes); | |
ff4e8d9a N |
339 | if (list_empty(&sh->lru) && |
340 | !test_bit(STRIPE_EXPANDING, &sh->state)) | |
16a53ecc N |
341 | BUG(); |
342 | list_del_init(&sh->lru); | |
1da177e4 LT |
343 | } |
344 | } | |
345 | } while (sh == NULL); | |
346 | ||
347 | if (sh) | |
348 | atomic_inc(&sh->count); | |
349 | ||
350 | spin_unlock_irq(&conf->device_lock); | |
351 | return sh; | |
352 | } | |
353 | ||
6712ecf8 N |
354 | static void |
355 | raid5_end_read_request(struct bio *bi, int error); | |
356 | static void | |
357 | raid5_end_write_request(struct bio *bi, int error); | |
91c00924 | 358 | |
c4e5ac0a | 359 | static void ops_run_io(struct stripe_head *sh, struct stripe_head_state *s) |
91c00924 DW |
360 | { |
361 | raid5_conf_t *conf = sh->raid_conf; | |
362 | int i, disks = sh->disks; | |
363 | ||
364 | might_sleep(); | |
365 | ||
366 | for (i = disks; i--; ) { | |
367 | int rw; | |
368 | struct bio *bi; | |
369 | mdk_rdev_t *rdev; | |
370 | if (test_and_clear_bit(R5_Wantwrite, &sh->dev[i].flags)) | |
371 | rw = WRITE; | |
372 | else if (test_and_clear_bit(R5_Wantread, &sh->dev[i].flags)) | |
373 | rw = READ; | |
374 | else | |
375 | continue; | |
376 | ||
377 | bi = &sh->dev[i].req; | |
378 | ||
379 | bi->bi_rw = rw; | |
380 | if (rw == WRITE) | |
381 | bi->bi_end_io = raid5_end_write_request; | |
382 | else | |
383 | bi->bi_end_io = raid5_end_read_request; | |
384 | ||
385 | rcu_read_lock(); | |
386 | rdev = rcu_dereference(conf->disks[i].rdev); | |
387 | if (rdev && test_bit(Faulty, &rdev->flags)) | |
388 | rdev = NULL; | |
389 | if (rdev) | |
390 | atomic_inc(&rdev->nr_pending); | |
391 | rcu_read_unlock(); | |
392 | ||
393 | if (rdev) { | |
c4e5ac0a | 394 | if (s->syncing || s->expanding || s->expanded) |
91c00924 DW |
395 | md_sync_acct(rdev->bdev, STRIPE_SECTORS); |
396 | ||
2b7497f0 DW |
397 | set_bit(STRIPE_IO_STARTED, &sh->state); |
398 | ||
91c00924 DW |
399 | bi->bi_bdev = rdev->bdev; |
400 | pr_debug("%s: for %llu schedule op %ld on disc %d\n", | |
e46b272b | 401 | __func__, (unsigned long long)sh->sector, |
91c00924 DW |
402 | bi->bi_rw, i); |
403 | atomic_inc(&sh->count); | |
404 | bi->bi_sector = sh->sector + rdev->data_offset; | |
405 | bi->bi_flags = 1 << BIO_UPTODATE; | |
406 | bi->bi_vcnt = 1; | |
407 | bi->bi_max_vecs = 1; | |
408 | bi->bi_idx = 0; | |
409 | bi->bi_io_vec = &sh->dev[i].vec; | |
410 | bi->bi_io_vec[0].bv_len = STRIPE_SIZE; | |
411 | bi->bi_io_vec[0].bv_offset = 0; | |
412 | bi->bi_size = STRIPE_SIZE; | |
413 | bi->bi_next = NULL; | |
414 | if (rw == WRITE && | |
415 | test_bit(R5_ReWrite, &sh->dev[i].flags)) | |
416 | atomic_add(STRIPE_SECTORS, | |
417 | &rdev->corrected_errors); | |
418 | generic_make_request(bi); | |
419 | } else { | |
420 | if (rw == WRITE) | |
421 | set_bit(STRIPE_DEGRADED, &sh->state); | |
422 | pr_debug("skip op %ld on disc %d for sector %llu\n", | |
423 | bi->bi_rw, i, (unsigned long long)sh->sector); | |
424 | clear_bit(R5_LOCKED, &sh->dev[i].flags); | |
425 | set_bit(STRIPE_HANDLE, &sh->state); | |
426 | } | |
427 | } | |
428 | } | |
429 | ||
430 | static struct dma_async_tx_descriptor * | |
431 | async_copy_data(int frombio, struct bio *bio, struct page *page, | |
432 | sector_t sector, struct dma_async_tx_descriptor *tx) | |
433 | { | |
434 | struct bio_vec *bvl; | |
435 | struct page *bio_page; | |
436 | int i; | |
437 | int page_offset; | |
438 | ||
439 | if (bio->bi_sector >= sector) | |
440 | page_offset = (signed)(bio->bi_sector - sector) * 512; | |
441 | else | |
442 | page_offset = (signed)(sector - bio->bi_sector) * -512; | |
443 | bio_for_each_segment(bvl, bio, i) { | |
444 | int len = bio_iovec_idx(bio, i)->bv_len; | |
445 | int clen; | |
446 | int b_offset = 0; | |
447 | ||
448 | if (page_offset < 0) { | |
449 | b_offset = -page_offset; | |
450 | page_offset += b_offset; | |
451 | len -= b_offset; | |
452 | } | |
453 | ||
454 | if (len > 0 && page_offset + len > STRIPE_SIZE) | |
455 | clen = STRIPE_SIZE - page_offset; | |
456 | else | |
457 | clen = len; | |
458 | ||
459 | if (clen > 0) { | |
460 | b_offset += bio_iovec_idx(bio, i)->bv_offset; | |
461 | bio_page = bio_iovec_idx(bio, i)->bv_page; | |
462 | if (frombio) | |
463 | tx = async_memcpy(page, bio_page, page_offset, | |
464 | b_offset, clen, | |
eb0645a8 | 465 | ASYNC_TX_DEP_ACK, |
91c00924 DW |
466 | tx, NULL, NULL); |
467 | else | |
468 | tx = async_memcpy(bio_page, page, b_offset, | |
469 | page_offset, clen, | |
eb0645a8 | 470 | ASYNC_TX_DEP_ACK, |
91c00924 DW |
471 | tx, NULL, NULL); |
472 | } | |
473 | if (clen < len) /* hit end of page */ | |
474 | break; | |
475 | page_offset += len; | |
476 | } | |
477 | ||
478 | return tx; | |
479 | } | |
480 | ||
481 | static void ops_complete_biofill(void *stripe_head_ref) | |
482 | { | |
483 | struct stripe_head *sh = stripe_head_ref; | |
484 | struct bio *return_bi = NULL; | |
485 | raid5_conf_t *conf = sh->raid_conf; | |
e4d84909 | 486 | int i; |
91c00924 | 487 | |
e46b272b | 488 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
489 | (unsigned long long)sh->sector); |
490 | ||
491 | /* clear completed biofills */ | |
83de75cc | 492 | spin_lock_irq(&conf->device_lock); |
91c00924 DW |
493 | for (i = sh->disks; i--; ) { |
494 | struct r5dev *dev = &sh->dev[i]; | |
91c00924 DW |
495 | |
496 | /* acknowledge completion of a biofill operation */ | |
e4d84909 DW |
497 | /* and check if we need to reply to a read request, |
498 | * new R5_Wantfill requests are held off until | |
83de75cc | 499 | * !STRIPE_BIOFILL_RUN |
e4d84909 DW |
500 | */ |
501 | if (test_and_clear_bit(R5_Wantfill, &dev->flags)) { | |
91c00924 | 502 | struct bio *rbi, *rbi2; |
91c00924 | 503 | |
91c00924 DW |
504 | BUG_ON(!dev->read); |
505 | rbi = dev->read; | |
506 | dev->read = NULL; | |
507 | while (rbi && rbi->bi_sector < | |
508 | dev->sector + STRIPE_SECTORS) { | |
509 | rbi2 = r5_next_bio(rbi, dev->sector); | |
91c00924 DW |
510 | if (--rbi->bi_phys_segments == 0) { |
511 | rbi->bi_next = return_bi; | |
512 | return_bi = rbi; | |
513 | } | |
91c00924 DW |
514 | rbi = rbi2; |
515 | } | |
516 | } | |
517 | } | |
83de75cc DW |
518 | spin_unlock_irq(&conf->device_lock); |
519 | clear_bit(STRIPE_BIOFILL_RUN, &sh->state); | |
91c00924 DW |
520 | |
521 | return_io(return_bi); | |
522 | ||
e4d84909 | 523 | set_bit(STRIPE_HANDLE, &sh->state); |
91c00924 DW |
524 | release_stripe(sh); |
525 | } | |
526 | ||
527 | static void ops_run_biofill(struct stripe_head *sh) | |
528 | { | |
529 | struct dma_async_tx_descriptor *tx = NULL; | |
530 | raid5_conf_t *conf = sh->raid_conf; | |
531 | int i; | |
532 | ||
e46b272b | 533 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
534 | (unsigned long long)sh->sector); |
535 | ||
536 | for (i = sh->disks; i--; ) { | |
537 | struct r5dev *dev = &sh->dev[i]; | |
538 | if (test_bit(R5_Wantfill, &dev->flags)) { | |
539 | struct bio *rbi; | |
540 | spin_lock_irq(&conf->device_lock); | |
541 | dev->read = rbi = dev->toread; | |
542 | dev->toread = NULL; | |
543 | spin_unlock_irq(&conf->device_lock); | |
544 | while (rbi && rbi->bi_sector < | |
545 | dev->sector + STRIPE_SECTORS) { | |
546 | tx = async_copy_data(0, rbi, dev->page, | |
547 | dev->sector, tx); | |
548 | rbi = r5_next_bio(rbi, dev->sector); | |
549 | } | |
550 | } | |
551 | } | |
552 | ||
553 | atomic_inc(&sh->count); | |
554 | async_trigger_callback(ASYNC_TX_DEP_ACK | ASYNC_TX_ACK, tx, | |
555 | ops_complete_biofill, sh); | |
556 | } | |
557 | ||
558 | static void ops_complete_compute5(void *stripe_head_ref) | |
559 | { | |
560 | struct stripe_head *sh = stripe_head_ref; | |
561 | int target = sh->ops.target; | |
562 | struct r5dev *tgt = &sh->dev[target]; | |
563 | ||
e46b272b | 564 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
565 | (unsigned long long)sh->sector); |
566 | ||
567 | set_bit(R5_UPTODATE, &tgt->flags); | |
568 | BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags)); | |
569 | clear_bit(R5_Wantcompute, &tgt->flags); | |
ecc65c9b DW |
570 | clear_bit(STRIPE_COMPUTE_RUN, &sh->state); |
571 | if (sh->check_state == check_state_compute_run) | |
572 | sh->check_state = check_state_compute_result; | |
91c00924 DW |
573 | set_bit(STRIPE_HANDLE, &sh->state); |
574 | release_stripe(sh); | |
575 | } | |
576 | ||
7b3a871e | 577 | static struct dma_async_tx_descriptor *ops_run_compute5(struct stripe_head *sh) |
91c00924 DW |
578 | { |
579 | /* kernel stack size limits the total number of disks */ | |
580 | int disks = sh->disks; | |
581 | struct page *xor_srcs[disks]; | |
582 | int target = sh->ops.target; | |
583 | struct r5dev *tgt = &sh->dev[target]; | |
584 | struct page *xor_dest = tgt->page; | |
585 | int count = 0; | |
586 | struct dma_async_tx_descriptor *tx; | |
587 | int i; | |
588 | ||
589 | pr_debug("%s: stripe %llu block: %d\n", | |
e46b272b | 590 | __func__, (unsigned long long)sh->sector, target); |
91c00924 DW |
591 | BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags)); |
592 | ||
593 | for (i = disks; i--; ) | |
594 | if (i != target) | |
595 | xor_srcs[count++] = sh->dev[i].page; | |
596 | ||
597 | atomic_inc(&sh->count); | |
598 | ||
599 | if (unlikely(count == 1)) | |
600 | tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE, | |
601 | 0, NULL, ops_complete_compute5, sh); | |
602 | else | |
603 | tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, | |
604 | ASYNC_TX_XOR_ZERO_DST, NULL, | |
605 | ops_complete_compute5, sh); | |
606 | ||
91c00924 DW |
607 | return tx; |
608 | } | |
609 | ||
610 | static void ops_complete_prexor(void *stripe_head_ref) | |
611 | { | |
612 | struct stripe_head *sh = stripe_head_ref; | |
613 | ||
e46b272b | 614 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 | 615 | (unsigned long long)sh->sector); |
91c00924 DW |
616 | } |
617 | ||
618 | static struct dma_async_tx_descriptor * | |
619 | ops_run_prexor(struct stripe_head *sh, struct dma_async_tx_descriptor *tx) | |
620 | { | |
621 | /* kernel stack size limits the total number of disks */ | |
622 | int disks = sh->disks; | |
623 | struct page *xor_srcs[disks]; | |
624 | int count = 0, pd_idx = sh->pd_idx, i; | |
625 | ||
626 | /* existing parity data subtracted */ | |
627 | struct page *xor_dest = xor_srcs[count++] = sh->dev[pd_idx].page; | |
628 | ||
e46b272b | 629 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
630 | (unsigned long long)sh->sector); |
631 | ||
632 | for (i = disks; i--; ) { | |
633 | struct r5dev *dev = &sh->dev[i]; | |
634 | /* Only process blocks that are known to be uptodate */ | |
d8ee0728 | 635 | if (test_bit(R5_Wantdrain, &dev->flags)) |
91c00924 DW |
636 | xor_srcs[count++] = dev->page; |
637 | } | |
638 | ||
639 | tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, | |
640 | ASYNC_TX_DEP_ACK | ASYNC_TX_XOR_DROP_DST, tx, | |
641 | ops_complete_prexor, sh); | |
642 | ||
643 | return tx; | |
644 | } | |
645 | ||
646 | static struct dma_async_tx_descriptor * | |
d8ee0728 | 647 | ops_run_biodrain(struct stripe_head *sh, struct dma_async_tx_descriptor *tx) |
91c00924 DW |
648 | { |
649 | int disks = sh->disks; | |
d8ee0728 | 650 | int i; |
91c00924 | 651 | |
e46b272b | 652 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
653 | (unsigned long long)sh->sector); |
654 | ||
655 | for (i = disks; i--; ) { | |
656 | struct r5dev *dev = &sh->dev[i]; | |
657 | struct bio *chosen; | |
91c00924 | 658 | |
d8ee0728 | 659 | if (test_and_clear_bit(R5_Wantdrain, &dev->flags)) { |
91c00924 DW |
660 | struct bio *wbi; |
661 | ||
662 | spin_lock(&sh->lock); | |
663 | chosen = dev->towrite; | |
664 | dev->towrite = NULL; | |
665 | BUG_ON(dev->written); | |
666 | wbi = dev->written = chosen; | |
667 | spin_unlock(&sh->lock); | |
668 | ||
669 | while (wbi && wbi->bi_sector < | |
670 | dev->sector + STRIPE_SECTORS) { | |
671 | tx = async_copy_data(1, wbi, dev->page, | |
672 | dev->sector, tx); | |
673 | wbi = r5_next_bio(wbi, dev->sector); | |
674 | } | |
675 | } | |
676 | } | |
677 | ||
678 | return tx; | |
679 | } | |
680 | ||
681 | static void ops_complete_postxor(void *stripe_head_ref) | |
91c00924 DW |
682 | { |
683 | struct stripe_head *sh = stripe_head_ref; | |
684 | int disks = sh->disks, i, pd_idx = sh->pd_idx; | |
685 | ||
e46b272b | 686 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
687 | (unsigned long long)sh->sector); |
688 | ||
689 | for (i = disks; i--; ) { | |
690 | struct r5dev *dev = &sh->dev[i]; | |
691 | if (dev->written || i == pd_idx) | |
692 | set_bit(R5_UPTODATE, &dev->flags); | |
693 | } | |
694 | ||
d8ee0728 DW |
695 | if (sh->reconstruct_state == reconstruct_state_drain_run) |
696 | sh->reconstruct_state = reconstruct_state_drain_result; | |
697 | else if (sh->reconstruct_state == reconstruct_state_prexor_drain_run) | |
698 | sh->reconstruct_state = reconstruct_state_prexor_drain_result; | |
699 | else { | |
700 | BUG_ON(sh->reconstruct_state != reconstruct_state_run); | |
701 | sh->reconstruct_state = reconstruct_state_result; | |
702 | } | |
91c00924 DW |
703 | |
704 | set_bit(STRIPE_HANDLE, &sh->state); | |
705 | release_stripe(sh); | |
706 | } | |
707 | ||
708 | static void | |
d8ee0728 | 709 | ops_run_postxor(struct stripe_head *sh, struct dma_async_tx_descriptor *tx) |
91c00924 DW |
710 | { |
711 | /* kernel stack size limits the total number of disks */ | |
712 | int disks = sh->disks; | |
713 | struct page *xor_srcs[disks]; | |
714 | ||
715 | int count = 0, pd_idx = sh->pd_idx, i; | |
716 | struct page *xor_dest; | |
d8ee0728 | 717 | int prexor = 0; |
91c00924 | 718 | unsigned long flags; |
91c00924 | 719 | |
e46b272b | 720 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
721 | (unsigned long long)sh->sector); |
722 | ||
723 | /* check if prexor is active which means only process blocks | |
724 | * that are part of a read-modify-write (written) | |
725 | */ | |
d8ee0728 DW |
726 | if (sh->reconstruct_state == reconstruct_state_prexor_drain_run) { |
727 | prexor = 1; | |
91c00924 DW |
728 | xor_dest = xor_srcs[count++] = sh->dev[pd_idx].page; |
729 | for (i = disks; i--; ) { | |
730 | struct r5dev *dev = &sh->dev[i]; | |
731 | if (dev->written) | |
732 | xor_srcs[count++] = dev->page; | |
733 | } | |
734 | } else { | |
735 | xor_dest = sh->dev[pd_idx].page; | |
736 | for (i = disks; i--; ) { | |
737 | struct r5dev *dev = &sh->dev[i]; | |
738 | if (i != pd_idx) | |
739 | xor_srcs[count++] = dev->page; | |
740 | } | |
741 | } | |
742 | ||
91c00924 DW |
743 | /* 1/ if we prexor'd then the dest is reused as a source |
744 | * 2/ if we did not prexor then we are redoing the parity | |
745 | * set ASYNC_TX_XOR_DROP_DST and ASYNC_TX_XOR_ZERO_DST | |
746 | * for the synchronous xor case | |
747 | */ | |
748 | flags = ASYNC_TX_DEP_ACK | ASYNC_TX_ACK | | |
749 | (prexor ? ASYNC_TX_XOR_DROP_DST : ASYNC_TX_XOR_ZERO_DST); | |
750 | ||
751 | atomic_inc(&sh->count); | |
752 | ||
753 | if (unlikely(count == 1)) { | |
754 | flags &= ~(ASYNC_TX_XOR_DROP_DST | ASYNC_TX_XOR_ZERO_DST); | |
755 | tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE, | |
d8ee0728 | 756 | flags, tx, ops_complete_postxor, sh); |
91c00924 DW |
757 | } else |
758 | tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, | |
d8ee0728 | 759 | flags, tx, ops_complete_postxor, sh); |
91c00924 DW |
760 | } |
761 | ||
762 | static void ops_complete_check(void *stripe_head_ref) | |
763 | { | |
764 | struct stripe_head *sh = stripe_head_ref; | |
91c00924 | 765 | |
e46b272b | 766 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
767 | (unsigned long long)sh->sector); |
768 | ||
ecc65c9b | 769 | sh->check_state = check_state_check_result; |
91c00924 DW |
770 | set_bit(STRIPE_HANDLE, &sh->state); |
771 | release_stripe(sh); | |
772 | } | |
773 | ||
774 | static void ops_run_check(struct stripe_head *sh) | |
775 | { | |
776 | /* kernel stack size limits the total number of disks */ | |
777 | int disks = sh->disks; | |
778 | struct page *xor_srcs[disks]; | |
779 | struct dma_async_tx_descriptor *tx; | |
780 | ||
781 | int count = 0, pd_idx = sh->pd_idx, i; | |
782 | struct page *xor_dest = xor_srcs[count++] = sh->dev[pd_idx].page; | |
783 | ||
e46b272b | 784 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
785 | (unsigned long long)sh->sector); |
786 | ||
787 | for (i = disks; i--; ) { | |
788 | struct r5dev *dev = &sh->dev[i]; | |
789 | if (i != pd_idx) | |
790 | xor_srcs[count++] = dev->page; | |
791 | } | |
792 | ||
793 | tx = async_xor_zero_sum(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, | |
794 | &sh->ops.zero_sum_result, 0, NULL, NULL, NULL); | |
795 | ||
91c00924 DW |
796 | atomic_inc(&sh->count); |
797 | tx = async_trigger_callback(ASYNC_TX_DEP_ACK | ASYNC_TX_ACK, tx, | |
798 | ops_complete_check, sh); | |
799 | } | |
800 | ||
600aa109 | 801 | static void raid5_run_ops(struct stripe_head *sh, unsigned long ops_request) |
91c00924 DW |
802 | { |
803 | int overlap_clear = 0, i, disks = sh->disks; | |
804 | struct dma_async_tx_descriptor *tx = NULL; | |
805 | ||
83de75cc | 806 | if (test_bit(STRIPE_OP_BIOFILL, &ops_request)) { |
91c00924 DW |
807 | ops_run_biofill(sh); |
808 | overlap_clear++; | |
809 | } | |
810 | ||
7b3a871e DW |
811 | if (test_bit(STRIPE_OP_COMPUTE_BLK, &ops_request)) { |
812 | tx = ops_run_compute5(sh); | |
813 | /* terminate the chain if postxor is not set to be run */ | |
814 | if (tx && !test_bit(STRIPE_OP_POSTXOR, &ops_request)) | |
815 | async_tx_ack(tx); | |
816 | } | |
91c00924 | 817 | |
600aa109 | 818 | if (test_bit(STRIPE_OP_PREXOR, &ops_request)) |
91c00924 DW |
819 | tx = ops_run_prexor(sh, tx); |
820 | ||
600aa109 | 821 | if (test_bit(STRIPE_OP_BIODRAIN, &ops_request)) { |
d8ee0728 | 822 | tx = ops_run_biodrain(sh, tx); |
91c00924 DW |
823 | overlap_clear++; |
824 | } | |
825 | ||
600aa109 | 826 | if (test_bit(STRIPE_OP_POSTXOR, &ops_request)) |
d8ee0728 | 827 | ops_run_postxor(sh, tx); |
91c00924 | 828 | |
ecc65c9b | 829 | if (test_bit(STRIPE_OP_CHECK, &ops_request)) |
91c00924 DW |
830 | ops_run_check(sh); |
831 | ||
91c00924 DW |
832 | if (overlap_clear) |
833 | for (i = disks; i--; ) { | |
834 | struct r5dev *dev = &sh->dev[i]; | |
835 | if (test_and_clear_bit(R5_Overlap, &dev->flags)) | |
836 | wake_up(&sh->raid_conf->wait_for_overlap); | |
837 | } | |
838 | } | |
839 | ||
3f294f4f | 840 | static int grow_one_stripe(raid5_conf_t *conf) |
1da177e4 LT |
841 | { |
842 | struct stripe_head *sh; | |
3f294f4f N |
843 | sh = kmem_cache_alloc(conf->slab_cache, GFP_KERNEL); |
844 | if (!sh) | |
845 | return 0; | |
846 | memset(sh, 0, sizeof(*sh) + (conf->raid_disks-1)*sizeof(struct r5dev)); | |
847 | sh->raid_conf = conf; | |
848 | spin_lock_init(&sh->lock); | |
849 | ||
850 | if (grow_buffers(sh, conf->raid_disks)) { | |
851 | shrink_buffers(sh, conf->raid_disks); | |
852 | kmem_cache_free(conf->slab_cache, sh); | |
853 | return 0; | |
854 | } | |
7ecaa1e6 | 855 | sh->disks = conf->raid_disks; |
3f294f4f N |
856 | /* we just created an active stripe so... */ |
857 | atomic_set(&sh->count, 1); | |
858 | atomic_inc(&conf->active_stripes); | |
859 | INIT_LIST_HEAD(&sh->lru); | |
860 | release_stripe(sh); | |
861 | return 1; | |
862 | } | |
863 | ||
864 | static int grow_stripes(raid5_conf_t *conf, int num) | |
865 | { | |
e18b890b | 866 | struct kmem_cache *sc; |
1da177e4 LT |
867 | int devs = conf->raid_disks; |
868 | ||
42b9bebe N |
869 | sprintf(conf->cache_name[0], "raid5-%s", mdname(conf->mddev)); |
870 | sprintf(conf->cache_name[1], "raid5-%s-alt", mdname(conf->mddev)); | |
ad01c9e3 N |
871 | conf->active_name = 0; |
872 | sc = kmem_cache_create(conf->cache_name[conf->active_name], | |
1da177e4 | 873 | sizeof(struct stripe_head)+(devs-1)*sizeof(struct r5dev), |
20c2df83 | 874 | 0, 0, NULL); |
1da177e4 LT |
875 | if (!sc) |
876 | return 1; | |
877 | conf->slab_cache = sc; | |
ad01c9e3 | 878 | conf->pool_size = devs; |
16a53ecc | 879 | while (num--) |
3f294f4f | 880 | if (!grow_one_stripe(conf)) |
1da177e4 | 881 | return 1; |
1da177e4 LT |
882 | return 0; |
883 | } | |
29269553 N |
884 | |
885 | #ifdef CONFIG_MD_RAID5_RESHAPE | |
ad01c9e3 N |
886 | static int resize_stripes(raid5_conf_t *conf, int newsize) |
887 | { | |
888 | /* Make all the stripes able to hold 'newsize' devices. | |
889 | * New slots in each stripe get 'page' set to a new page. | |
890 | * | |
891 | * This happens in stages: | |
892 | * 1/ create a new kmem_cache and allocate the required number of | |
893 | * stripe_heads. | |
894 | * 2/ gather all the old stripe_heads and tranfer the pages across | |
895 | * to the new stripe_heads. This will have the side effect of | |
896 | * freezing the array as once all stripe_heads have been collected, | |
897 | * no IO will be possible. Old stripe heads are freed once their | |
898 | * pages have been transferred over, and the old kmem_cache is | |
899 | * freed when all stripes are done. | |
900 | * 3/ reallocate conf->disks to be suitable bigger. If this fails, | |
901 | * we simple return a failre status - no need to clean anything up. | |
902 | * 4/ allocate new pages for the new slots in the new stripe_heads. | |
903 | * If this fails, we don't bother trying the shrink the | |
904 | * stripe_heads down again, we just leave them as they are. | |
905 | * As each stripe_head is processed the new one is released into | |
906 | * active service. | |
907 | * | |
908 | * Once step2 is started, we cannot afford to wait for a write, | |
909 | * so we use GFP_NOIO allocations. | |
910 | */ | |
911 | struct stripe_head *osh, *nsh; | |
912 | LIST_HEAD(newstripes); | |
913 | struct disk_info *ndisks; | |
b5470dc5 | 914 | int err; |
e18b890b | 915 | struct kmem_cache *sc; |
ad01c9e3 N |
916 | int i; |
917 | ||
918 | if (newsize <= conf->pool_size) | |
919 | return 0; /* never bother to shrink */ | |
920 | ||
b5470dc5 DW |
921 | err = md_allow_write(conf->mddev); |
922 | if (err) | |
923 | return err; | |
2a2275d6 | 924 | |
ad01c9e3 N |
925 | /* Step 1 */ |
926 | sc = kmem_cache_create(conf->cache_name[1-conf->active_name], | |
927 | sizeof(struct stripe_head)+(newsize-1)*sizeof(struct r5dev), | |
20c2df83 | 928 | 0, 0, NULL); |
ad01c9e3 N |
929 | if (!sc) |
930 | return -ENOMEM; | |
931 | ||
932 | for (i = conf->max_nr_stripes; i; i--) { | |
933 | nsh = kmem_cache_alloc(sc, GFP_KERNEL); | |
934 | if (!nsh) | |
935 | break; | |
936 | ||
937 | memset(nsh, 0, sizeof(*nsh) + (newsize-1)*sizeof(struct r5dev)); | |
938 | ||
939 | nsh->raid_conf = conf; | |
940 | spin_lock_init(&nsh->lock); | |
941 | ||
942 | list_add(&nsh->lru, &newstripes); | |
943 | } | |
944 | if (i) { | |
945 | /* didn't get enough, give up */ | |
946 | while (!list_empty(&newstripes)) { | |
947 | nsh = list_entry(newstripes.next, struct stripe_head, lru); | |
948 | list_del(&nsh->lru); | |
949 | kmem_cache_free(sc, nsh); | |
950 | } | |
951 | kmem_cache_destroy(sc); | |
952 | return -ENOMEM; | |
953 | } | |
954 | /* Step 2 - Must use GFP_NOIO now. | |
955 | * OK, we have enough stripes, start collecting inactive | |
956 | * stripes and copying them over | |
957 | */ | |
958 | list_for_each_entry(nsh, &newstripes, lru) { | |
959 | spin_lock_irq(&conf->device_lock); | |
960 | wait_event_lock_irq(conf->wait_for_stripe, | |
961 | !list_empty(&conf->inactive_list), | |
962 | conf->device_lock, | |
b3b46be3 | 963 | unplug_slaves(conf->mddev) |
ad01c9e3 N |
964 | ); |
965 | osh = get_free_stripe(conf); | |
966 | spin_unlock_irq(&conf->device_lock); | |
967 | atomic_set(&nsh->count, 1); | |
968 | for(i=0; i<conf->pool_size; i++) | |
969 | nsh->dev[i].page = osh->dev[i].page; | |
970 | for( ; i<newsize; i++) | |
971 | nsh->dev[i].page = NULL; | |
972 | kmem_cache_free(conf->slab_cache, osh); | |
973 | } | |
974 | kmem_cache_destroy(conf->slab_cache); | |
975 | ||
976 | /* Step 3. | |
977 | * At this point, we are holding all the stripes so the array | |
978 | * is completely stalled, so now is a good time to resize | |
979 | * conf->disks. | |
980 | */ | |
981 | ndisks = kzalloc(newsize * sizeof(struct disk_info), GFP_NOIO); | |
982 | if (ndisks) { | |
983 | for (i=0; i<conf->raid_disks; i++) | |
984 | ndisks[i] = conf->disks[i]; | |
985 | kfree(conf->disks); | |
986 | conf->disks = ndisks; | |
987 | } else | |
988 | err = -ENOMEM; | |
989 | ||
990 | /* Step 4, return new stripes to service */ | |
991 | while(!list_empty(&newstripes)) { | |
992 | nsh = list_entry(newstripes.next, struct stripe_head, lru); | |
993 | list_del_init(&nsh->lru); | |
994 | for (i=conf->raid_disks; i < newsize; i++) | |
995 | if (nsh->dev[i].page == NULL) { | |
996 | struct page *p = alloc_page(GFP_NOIO); | |
997 | nsh->dev[i].page = p; | |
998 | if (!p) | |
999 | err = -ENOMEM; | |
1000 | } | |
1001 | release_stripe(nsh); | |
1002 | } | |
1003 | /* critical section pass, GFP_NOIO no longer needed */ | |
1004 | ||
1005 | conf->slab_cache = sc; | |
1006 | conf->active_name = 1-conf->active_name; | |
1007 | conf->pool_size = newsize; | |
1008 | return err; | |
1009 | } | |
29269553 | 1010 | #endif |
1da177e4 | 1011 | |
3f294f4f | 1012 | static int drop_one_stripe(raid5_conf_t *conf) |
1da177e4 LT |
1013 | { |
1014 | struct stripe_head *sh; | |
1015 | ||
3f294f4f N |
1016 | spin_lock_irq(&conf->device_lock); |
1017 | sh = get_free_stripe(conf); | |
1018 | spin_unlock_irq(&conf->device_lock); | |
1019 | if (!sh) | |
1020 | return 0; | |
78bafebd | 1021 | BUG_ON(atomic_read(&sh->count)); |
ad01c9e3 | 1022 | shrink_buffers(sh, conf->pool_size); |
3f294f4f N |
1023 | kmem_cache_free(conf->slab_cache, sh); |
1024 | atomic_dec(&conf->active_stripes); | |
1025 | return 1; | |
1026 | } | |
1027 | ||
1028 | static void shrink_stripes(raid5_conf_t *conf) | |
1029 | { | |
1030 | while (drop_one_stripe(conf)) | |
1031 | ; | |
1032 | ||
29fc7e3e N |
1033 | if (conf->slab_cache) |
1034 | kmem_cache_destroy(conf->slab_cache); | |
1da177e4 LT |
1035 | conf->slab_cache = NULL; |
1036 | } | |
1037 | ||
6712ecf8 | 1038 | static void raid5_end_read_request(struct bio * bi, int error) |
1da177e4 LT |
1039 | { |
1040 | struct stripe_head *sh = bi->bi_private; | |
1041 | raid5_conf_t *conf = sh->raid_conf; | |
7ecaa1e6 | 1042 | int disks = sh->disks, i; |
1da177e4 | 1043 | int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags); |
d6950432 N |
1044 | char b[BDEVNAME_SIZE]; |
1045 | mdk_rdev_t *rdev; | |
1da177e4 | 1046 | |
1da177e4 LT |
1047 | |
1048 | for (i=0 ; i<disks; i++) | |
1049 | if (bi == &sh->dev[i].req) | |
1050 | break; | |
1051 | ||
45b4233c DW |
1052 | pr_debug("end_read_request %llu/%d, count: %d, uptodate %d.\n", |
1053 | (unsigned long long)sh->sector, i, atomic_read(&sh->count), | |
1da177e4 LT |
1054 | uptodate); |
1055 | if (i == disks) { | |
1056 | BUG(); | |
6712ecf8 | 1057 | return; |
1da177e4 LT |
1058 | } |
1059 | ||
1060 | if (uptodate) { | |
1da177e4 | 1061 | set_bit(R5_UPTODATE, &sh->dev[i].flags); |
4e5314b5 | 1062 | if (test_bit(R5_ReadError, &sh->dev[i].flags)) { |
d6950432 | 1063 | rdev = conf->disks[i].rdev; |
6be9d494 BS |
1064 | printk_rl(KERN_INFO "raid5:%s: read error corrected" |
1065 | " (%lu sectors at %llu on %s)\n", | |
1066 | mdname(conf->mddev), STRIPE_SECTORS, | |
1067 | (unsigned long long)(sh->sector | |
1068 | + rdev->data_offset), | |
1069 | bdevname(rdev->bdev, b)); | |
4e5314b5 N |
1070 | clear_bit(R5_ReadError, &sh->dev[i].flags); |
1071 | clear_bit(R5_ReWrite, &sh->dev[i].flags); | |
1072 | } | |
ba22dcbf N |
1073 | if (atomic_read(&conf->disks[i].rdev->read_errors)) |
1074 | atomic_set(&conf->disks[i].rdev->read_errors, 0); | |
1da177e4 | 1075 | } else { |
d6950432 | 1076 | const char *bdn = bdevname(conf->disks[i].rdev->bdev, b); |
ba22dcbf | 1077 | int retry = 0; |
d6950432 N |
1078 | rdev = conf->disks[i].rdev; |
1079 | ||
1da177e4 | 1080 | clear_bit(R5_UPTODATE, &sh->dev[i].flags); |
d6950432 | 1081 | atomic_inc(&rdev->read_errors); |
ba22dcbf | 1082 | if (conf->mddev->degraded) |
6be9d494 BS |
1083 | printk_rl(KERN_WARNING |
1084 | "raid5:%s: read error not correctable " | |
1085 | "(sector %llu on %s).\n", | |
1086 | mdname(conf->mddev), | |
1087 | (unsigned long long)(sh->sector | |
1088 | + rdev->data_offset), | |
1089 | bdn); | |
ba22dcbf | 1090 | else if (test_bit(R5_ReWrite, &sh->dev[i].flags)) |
4e5314b5 | 1091 | /* Oh, no!!! */ |
6be9d494 BS |
1092 | printk_rl(KERN_WARNING |
1093 | "raid5:%s: read error NOT corrected!! " | |
1094 | "(sector %llu on %s).\n", | |
1095 | mdname(conf->mddev), | |
1096 | (unsigned long long)(sh->sector | |
1097 | + rdev->data_offset), | |
1098 | bdn); | |
d6950432 | 1099 | else if (atomic_read(&rdev->read_errors) |
ba22dcbf | 1100 | > conf->max_nr_stripes) |
14f8d26b | 1101 | printk(KERN_WARNING |
d6950432 N |
1102 | "raid5:%s: Too many read errors, failing device %s.\n", |
1103 | mdname(conf->mddev), bdn); | |
ba22dcbf N |
1104 | else |
1105 | retry = 1; | |
1106 | if (retry) | |
1107 | set_bit(R5_ReadError, &sh->dev[i].flags); | |
1108 | else { | |
4e5314b5 N |
1109 | clear_bit(R5_ReadError, &sh->dev[i].flags); |
1110 | clear_bit(R5_ReWrite, &sh->dev[i].flags); | |
d6950432 | 1111 | md_error(conf->mddev, rdev); |
ba22dcbf | 1112 | } |
1da177e4 LT |
1113 | } |
1114 | rdev_dec_pending(conf->disks[i].rdev, conf->mddev); | |
1da177e4 LT |
1115 | clear_bit(R5_LOCKED, &sh->dev[i].flags); |
1116 | set_bit(STRIPE_HANDLE, &sh->state); | |
1117 | release_stripe(sh); | |
1da177e4 LT |
1118 | } |
1119 | ||
6712ecf8 | 1120 | static void raid5_end_write_request (struct bio *bi, int error) |
1da177e4 LT |
1121 | { |
1122 | struct stripe_head *sh = bi->bi_private; | |
1123 | raid5_conf_t *conf = sh->raid_conf; | |
7ecaa1e6 | 1124 | int disks = sh->disks, i; |
1da177e4 LT |
1125 | int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags); |
1126 | ||
1da177e4 LT |
1127 | for (i=0 ; i<disks; i++) |
1128 | if (bi == &sh->dev[i].req) | |
1129 | break; | |
1130 | ||
45b4233c | 1131 | pr_debug("end_write_request %llu/%d, count %d, uptodate: %d.\n", |
1da177e4 LT |
1132 | (unsigned long long)sh->sector, i, atomic_read(&sh->count), |
1133 | uptodate); | |
1134 | if (i == disks) { | |
1135 | BUG(); | |
6712ecf8 | 1136 | return; |
1da177e4 LT |
1137 | } |
1138 | ||
1da177e4 LT |
1139 | if (!uptodate) |
1140 | md_error(conf->mddev, conf->disks[i].rdev); | |
1141 | ||
1142 | rdev_dec_pending(conf->disks[i].rdev, conf->mddev); | |
1143 | ||
1144 | clear_bit(R5_LOCKED, &sh->dev[i].flags); | |
1145 | set_bit(STRIPE_HANDLE, &sh->state); | |
c04be0aa | 1146 | release_stripe(sh); |
1da177e4 LT |
1147 | } |
1148 | ||
1149 | ||
1150 | static sector_t compute_blocknr(struct stripe_head *sh, int i); | |
1151 | ||
1152 | static void raid5_build_block (struct stripe_head *sh, int i) | |
1153 | { | |
1154 | struct r5dev *dev = &sh->dev[i]; | |
1155 | ||
1156 | bio_init(&dev->req); | |
1157 | dev->req.bi_io_vec = &dev->vec; | |
1158 | dev->req.bi_vcnt++; | |
1159 | dev->req.bi_max_vecs++; | |
1160 | dev->vec.bv_page = dev->page; | |
1161 | dev->vec.bv_len = STRIPE_SIZE; | |
1162 | dev->vec.bv_offset = 0; | |
1163 | ||
1164 | dev->req.bi_sector = sh->sector; | |
1165 | dev->req.bi_private = sh; | |
1166 | ||
1167 | dev->flags = 0; | |
16a53ecc | 1168 | dev->sector = compute_blocknr(sh, i); |
1da177e4 LT |
1169 | } |
1170 | ||
1171 | static void error(mddev_t *mddev, mdk_rdev_t *rdev) | |
1172 | { | |
1173 | char b[BDEVNAME_SIZE]; | |
1174 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; | |
45b4233c | 1175 | pr_debug("raid5: error called\n"); |
1da177e4 | 1176 | |
b2d444d7 | 1177 | if (!test_bit(Faulty, &rdev->flags)) { |
850b2b42 | 1178 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
c04be0aa N |
1179 | if (test_and_clear_bit(In_sync, &rdev->flags)) { |
1180 | unsigned long flags; | |
1181 | spin_lock_irqsave(&conf->device_lock, flags); | |
1da177e4 | 1182 | mddev->degraded++; |
c04be0aa | 1183 | spin_unlock_irqrestore(&conf->device_lock, flags); |
1da177e4 LT |
1184 | /* |
1185 | * if recovery was running, make sure it aborts. | |
1186 | */ | |
dfc70645 | 1187 | set_bit(MD_RECOVERY_INTR, &mddev->recovery); |
1da177e4 | 1188 | } |
b2d444d7 | 1189 | set_bit(Faulty, &rdev->flags); |
1da177e4 | 1190 | printk (KERN_ALERT |
d7a420c9 NA |
1191 | "raid5: Disk failure on %s, disabling device.\n" |
1192 | "raid5: Operation continuing on %d devices.\n", | |
02c2de8c | 1193 | bdevname(rdev->bdev,b), conf->raid_disks - mddev->degraded); |
1da177e4 | 1194 | } |
16a53ecc | 1195 | } |
1da177e4 LT |
1196 | |
1197 | /* | |
1198 | * Input: a 'big' sector number, | |
1199 | * Output: index of the data and parity disk, and the sector # in them. | |
1200 | */ | |
1201 | static sector_t raid5_compute_sector(sector_t r_sector, unsigned int raid_disks, | |
1202 | unsigned int data_disks, unsigned int * dd_idx, | |
1203 | unsigned int * pd_idx, raid5_conf_t *conf) | |
1204 | { | |
1205 | long stripe; | |
1206 | unsigned long chunk_number; | |
1207 | unsigned int chunk_offset; | |
1208 | sector_t new_sector; | |
1209 | int sectors_per_chunk = conf->chunk_size >> 9; | |
1210 | ||
1211 | /* First compute the information on this sector */ | |
1212 | ||
1213 | /* | |
1214 | * Compute the chunk number and the sector offset inside the chunk | |
1215 | */ | |
1216 | chunk_offset = sector_div(r_sector, sectors_per_chunk); | |
1217 | chunk_number = r_sector; | |
1218 | BUG_ON(r_sector != chunk_number); | |
1219 | ||
1220 | /* | |
1221 | * Compute the stripe number | |
1222 | */ | |
1223 | stripe = chunk_number / data_disks; | |
1224 | ||
1225 | /* | |
1226 | * Compute the data disk and parity disk indexes inside the stripe | |
1227 | */ | |
1228 | *dd_idx = chunk_number % data_disks; | |
1229 | ||
1230 | /* | |
1231 | * Select the parity disk based on the user selected algorithm. | |
1232 | */ | |
16a53ecc N |
1233 | switch(conf->level) { |
1234 | case 4: | |
1da177e4 | 1235 | *pd_idx = data_disks; |
16a53ecc N |
1236 | break; |
1237 | case 5: | |
1238 | switch (conf->algorithm) { | |
1da177e4 LT |
1239 | case ALGORITHM_LEFT_ASYMMETRIC: |
1240 | *pd_idx = data_disks - stripe % raid_disks; | |
1241 | if (*dd_idx >= *pd_idx) | |
1242 | (*dd_idx)++; | |
1243 | break; | |
1244 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
1245 | *pd_idx = stripe % raid_disks; | |
1246 | if (*dd_idx >= *pd_idx) | |
1247 | (*dd_idx)++; | |
1248 | break; | |
1249 | case ALGORITHM_LEFT_SYMMETRIC: | |
1250 | *pd_idx = data_disks - stripe % raid_disks; | |
1251 | *dd_idx = (*pd_idx + 1 + *dd_idx) % raid_disks; | |
1252 | break; | |
1253 | case ALGORITHM_RIGHT_SYMMETRIC: | |
1254 | *pd_idx = stripe % raid_disks; | |
1255 | *dd_idx = (*pd_idx + 1 + *dd_idx) % raid_disks; | |
1256 | break; | |
1257 | default: | |
14f8d26b | 1258 | printk(KERN_ERR "raid5: unsupported algorithm %d\n", |
1da177e4 | 1259 | conf->algorithm); |
16a53ecc N |
1260 | } |
1261 | break; | |
1262 | case 6: | |
1263 | ||
1264 | /**** FIX THIS ****/ | |
1265 | switch (conf->algorithm) { | |
1266 | case ALGORITHM_LEFT_ASYMMETRIC: | |
1267 | *pd_idx = raid_disks - 1 - (stripe % raid_disks); | |
1268 | if (*pd_idx == raid_disks-1) | |
1269 | (*dd_idx)++; /* Q D D D P */ | |
1270 | else if (*dd_idx >= *pd_idx) | |
1271 | (*dd_idx) += 2; /* D D P Q D */ | |
1272 | break; | |
1273 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
1274 | *pd_idx = stripe % raid_disks; | |
1275 | if (*pd_idx == raid_disks-1) | |
1276 | (*dd_idx)++; /* Q D D D P */ | |
1277 | else if (*dd_idx >= *pd_idx) | |
1278 | (*dd_idx) += 2; /* D D P Q D */ | |
1279 | break; | |
1280 | case ALGORITHM_LEFT_SYMMETRIC: | |
1281 | *pd_idx = raid_disks - 1 - (stripe % raid_disks); | |
1282 | *dd_idx = (*pd_idx + 2 + *dd_idx) % raid_disks; | |
1283 | break; | |
1284 | case ALGORITHM_RIGHT_SYMMETRIC: | |
1285 | *pd_idx = stripe % raid_disks; | |
1286 | *dd_idx = (*pd_idx + 2 + *dd_idx) % raid_disks; | |
1287 | break; | |
1288 | default: | |
1289 | printk (KERN_CRIT "raid6: unsupported algorithm %d\n", | |
1290 | conf->algorithm); | |
1291 | } | |
1292 | break; | |
1da177e4 LT |
1293 | } |
1294 | ||
1295 | /* | |
1296 | * Finally, compute the new sector number | |
1297 | */ | |
1298 | new_sector = (sector_t)stripe * sectors_per_chunk + chunk_offset; | |
1299 | return new_sector; | |
1300 | } | |
1301 | ||
1302 | ||
1303 | static sector_t compute_blocknr(struct stripe_head *sh, int i) | |
1304 | { | |
1305 | raid5_conf_t *conf = sh->raid_conf; | |
b875e531 N |
1306 | int raid_disks = sh->disks; |
1307 | int data_disks = raid_disks - conf->max_degraded; | |
1da177e4 LT |
1308 | sector_t new_sector = sh->sector, check; |
1309 | int sectors_per_chunk = conf->chunk_size >> 9; | |
1310 | sector_t stripe; | |
1311 | int chunk_offset; | |
1312 | int chunk_number, dummy1, dummy2, dd_idx = i; | |
1313 | sector_t r_sector; | |
1314 | ||
16a53ecc | 1315 | |
1da177e4 LT |
1316 | chunk_offset = sector_div(new_sector, sectors_per_chunk); |
1317 | stripe = new_sector; | |
1318 | BUG_ON(new_sector != stripe); | |
1319 | ||
16a53ecc N |
1320 | if (i == sh->pd_idx) |
1321 | return 0; | |
1322 | switch(conf->level) { | |
1323 | case 4: break; | |
1324 | case 5: | |
1325 | switch (conf->algorithm) { | |
1da177e4 LT |
1326 | case ALGORITHM_LEFT_ASYMMETRIC: |
1327 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
1328 | if (i > sh->pd_idx) | |
1329 | i--; | |
1330 | break; | |
1331 | case ALGORITHM_LEFT_SYMMETRIC: | |
1332 | case ALGORITHM_RIGHT_SYMMETRIC: | |
1333 | if (i < sh->pd_idx) | |
1334 | i += raid_disks; | |
1335 | i -= (sh->pd_idx + 1); | |
1336 | break; | |
1337 | default: | |
14f8d26b | 1338 | printk(KERN_ERR "raid5: unsupported algorithm %d\n", |
16a53ecc N |
1339 | conf->algorithm); |
1340 | } | |
1341 | break; | |
1342 | case 6: | |
16a53ecc N |
1343 | if (i == raid6_next_disk(sh->pd_idx, raid_disks)) |
1344 | return 0; /* It is the Q disk */ | |
1345 | switch (conf->algorithm) { | |
1346 | case ALGORITHM_LEFT_ASYMMETRIC: | |
1347 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
1348 | if (sh->pd_idx == raid_disks-1) | |
1349 | i--; /* Q D D D P */ | |
1350 | else if (i > sh->pd_idx) | |
1351 | i -= 2; /* D D P Q D */ | |
1352 | break; | |
1353 | case ALGORITHM_LEFT_SYMMETRIC: | |
1354 | case ALGORITHM_RIGHT_SYMMETRIC: | |
1355 | if (sh->pd_idx == raid_disks-1) | |
1356 | i--; /* Q D D D P */ | |
1357 | else { | |
1358 | /* D D P Q D */ | |
1359 | if (i < sh->pd_idx) | |
1360 | i += raid_disks; | |
1361 | i -= (sh->pd_idx + 2); | |
1362 | } | |
1363 | break; | |
1364 | default: | |
1365 | printk (KERN_CRIT "raid6: unsupported algorithm %d\n", | |
1da177e4 | 1366 | conf->algorithm); |
16a53ecc N |
1367 | } |
1368 | break; | |
1da177e4 LT |
1369 | } |
1370 | ||
1371 | chunk_number = stripe * data_disks + i; | |
1372 | r_sector = (sector_t)chunk_number * sectors_per_chunk + chunk_offset; | |
1373 | ||
1374 | check = raid5_compute_sector (r_sector, raid_disks, data_disks, &dummy1, &dummy2, conf); | |
1375 | if (check != sh->sector || dummy1 != dd_idx || dummy2 != sh->pd_idx) { | |
14f8d26b | 1376 | printk(KERN_ERR "compute_blocknr: map not correct\n"); |
1da177e4 LT |
1377 | return 0; |
1378 | } | |
1379 | return r_sector; | |
1380 | } | |
1381 | ||
1382 | ||
1383 | ||
1384 | /* | |
16a53ecc N |
1385 | * Copy data between a page in the stripe cache, and one or more bion |
1386 | * The page could align with the middle of the bio, or there could be | |
1387 | * several bion, each with several bio_vecs, which cover part of the page | |
1388 | * Multiple bion are linked together on bi_next. There may be extras | |
1389 | * at the end of this list. We ignore them. | |
1da177e4 LT |
1390 | */ |
1391 | static void copy_data(int frombio, struct bio *bio, | |
1392 | struct page *page, | |
1393 | sector_t sector) | |
1394 | { | |
1395 | char *pa = page_address(page); | |
1396 | struct bio_vec *bvl; | |
1397 | int i; | |
1398 | int page_offset; | |
1399 | ||
1400 | if (bio->bi_sector >= sector) | |
1401 | page_offset = (signed)(bio->bi_sector - sector) * 512; | |
1402 | else | |
1403 | page_offset = (signed)(sector - bio->bi_sector) * -512; | |
1404 | bio_for_each_segment(bvl, bio, i) { | |
1405 | int len = bio_iovec_idx(bio,i)->bv_len; | |
1406 | int clen; | |
1407 | int b_offset = 0; | |
1408 | ||
1409 | if (page_offset < 0) { | |
1410 | b_offset = -page_offset; | |
1411 | page_offset += b_offset; | |
1412 | len -= b_offset; | |
1413 | } | |
1414 | ||
1415 | if (len > 0 && page_offset + len > STRIPE_SIZE) | |
1416 | clen = STRIPE_SIZE - page_offset; | |
1417 | else clen = len; | |
16a53ecc | 1418 | |
1da177e4 LT |
1419 | if (clen > 0) { |
1420 | char *ba = __bio_kmap_atomic(bio, i, KM_USER0); | |
1421 | if (frombio) | |
1422 | memcpy(pa+page_offset, ba+b_offset, clen); | |
1423 | else | |
1424 | memcpy(ba+b_offset, pa+page_offset, clen); | |
1425 | __bio_kunmap_atomic(ba, KM_USER0); | |
1426 | } | |
1427 | if (clen < len) /* hit end of page */ | |
1428 | break; | |
1429 | page_offset += len; | |
1430 | } | |
1431 | } | |
1432 | ||
9bc89cd8 DW |
1433 | #define check_xor() do { \ |
1434 | if (count == MAX_XOR_BLOCKS) { \ | |
1435 | xor_blocks(count, STRIPE_SIZE, dest, ptr);\ | |
1436 | count = 0; \ | |
1437 | } \ | |
1da177e4 LT |
1438 | } while(0) |
1439 | ||
16a53ecc N |
1440 | static void compute_parity6(struct stripe_head *sh, int method) |
1441 | { | |
1442 | raid6_conf_t *conf = sh->raid_conf; | |
f416885e | 1443 | int i, pd_idx = sh->pd_idx, qd_idx, d0_idx, disks = sh->disks, count; |
16a53ecc N |
1444 | struct bio *chosen; |
1445 | /**** FIX THIS: This could be very bad if disks is close to 256 ****/ | |
1446 | void *ptrs[disks]; | |
1447 | ||
1448 | qd_idx = raid6_next_disk(pd_idx, disks); | |
1449 | d0_idx = raid6_next_disk(qd_idx, disks); | |
1450 | ||
45b4233c | 1451 | pr_debug("compute_parity, stripe %llu, method %d\n", |
16a53ecc N |
1452 | (unsigned long long)sh->sector, method); |
1453 | ||
1454 | switch(method) { | |
1455 | case READ_MODIFY_WRITE: | |
1456 | BUG(); /* READ_MODIFY_WRITE N/A for RAID-6 */ | |
1457 | case RECONSTRUCT_WRITE: | |
1458 | for (i= disks; i-- ;) | |
1459 | if ( i != pd_idx && i != qd_idx && sh->dev[i].towrite ) { | |
1460 | chosen = sh->dev[i].towrite; | |
1461 | sh->dev[i].towrite = NULL; | |
1462 | ||
1463 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) | |
1464 | wake_up(&conf->wait_for_overlap); | |
1465 | ||
52e5f9d1 | 1466 | BUG_ON(sh->dev[i].written); |
16a53ecc N |
1467 | sh->dev[i].written = chosen; |
1468 | } | |
1469 | break; | |
1470 | case CHECK_PARITY: | |
1471 | BUG(); /* Not implemented yet */ | |
1472 | } | |
1473 | ||
1474 | for (i = disks; i--;) | |
1475 | if (sh->dev[i].written) { | |
1476 | sector_t sector = sh->dev[i].sector; | |
1477 | struct bio *wbi = sh->dev[i].written; | |
1478 | while (wbi && wbi->bi_sector < sector + STRIPE_SECTORS) { | |
1479 | copy_data(1, wbi, sh->dev[i].page, sector); | |
1480 | wbi = r5_next_bio(wbi, sector); | |
1481 | } | |
1482 | ||
1483 | set_bit(R5_LOCKED, &sh->dev[i].flags); | |
1484 | set_bit(R5_UPTODATE, &sh->dev[i].flags); | |
1485 | } | |
1486 | ||
1487 | // switch(method) { | |
1488 | // case RECONSTRUCT_WRITE: | |
1489 | // case CHECK_PARITY: | |
1490 | // case UPDATE_PARITY: | |
1491 | /* Note that unlike RAID-5, the ordering of the disks matters greatly. */ | |
1492 | /* FIX: Is this ordering of drives even remotely optimal? */ | |
1493 | count = 0; | |
1494 | i = d0_idx; | |
1495 | do { | |
1496 | ptrs[count++] = page_address(sh->dev[i].page); | |
1497 | if (count <= disks-2 && !test_bit(R5_UPTODATE, &sh->dev[i].flags)) | |
1498 | printk("block %d/%d not uptodate on parity calc\n", i,count); | |
1499 | i = raid6_next_disk(i, disks); | |
1500 | } while ( i != d0_idx ); | |
1501 | // break; | |
1502 | // } | |
1503 | ||
1504 | raid6_call.gen_syndrome(disks, STRIPE_SIZE, ptrs); | |
1505 | ||
1506 | switch(method) { | |
1507 | case RECONSTRUCT_WRITE: | |
1508 | set_bit(R5_UPTODATE, &sh->dev[pd_idx].flags); | |
1509 | set_bit(R5_UPTODATE, &sh->dev[qd_idx].flags); | |
1510 | set_bit(R5_LOCKED, &sh->dev[pd_idx].flags); | |
1511 | set_bit(R5_LOCKED, &sh->dev[qd_idx].flags); | |
1512 | break; | |
1513 | case UPDATE_PARITY: | |
1514 | set_bit(R5_UPTODATE, &sh->dev[pd_idx].flags); | |
1515 | set_bit(R5_UPTODATE, &sh->dev[qd_idx].flags); | |
1516 | break; | |
1517 | } | |
1518 | } | |
1519 | ||
1520 | ||
1521 | /* Compute one missing block */ | |
1522 | static void compute_block_1(struct stripe_head *sh, int dd_idx, int nozero) | |
1523 | { | |
f416885e | 1524 | int i, count, disks = sh->disks; |
9bc89cd8 | 1525 | void *ptr[MAX_XOR_BLOCKS], *dest, *p; |
16a53ecc N |
1526 | int pd_idx = sh->pd_idx; |
1527 | int qd_idx = raid6_next_disk(pd_idx, disks); | |
1528 | ||
45b4233c | 1529 | pr_debug("compute_block_1, stripe %llu, idx %d\n", |
16a53ecc N |
1530 | (unsigned long long)sh->sector, dd_idx); |
1531 | ||
1532 | if ( dd_idx == qd_idx ) { | |
1533 | /* We're actually computing the Q drive */ | |
1534 | compute_parity6(sh, UPDATE_PARITY); | |
1535 | } else { | |
9bc89cd8 DW |
1536 | dest = page_address(sh->dev[dd_idx].page); |
1537 | if (!nozero) memset(dest, 0, STRIPE_SIZE); | |
1538 | count = 0; | |
16a53ecc N |
1539 | for (i = disks ; i--; ) { |
1540 | if (i == dd_idx || i == qd_idx) | |
1541 | continue; | |
1542 | p = page_address(sh->dev[i].page); | |
1543 | if (test_bit(R5_UPTODATE, &sh->dev[i].flags)) | |
1544 | ptr[count++] = p; | |
1545 | else | |
1546 | printk("compute_block() %d, stripe %llu, %d" | |
1547 | " not present\n", dd_idx, | |
1548 | (unsigned long long)sh->sector, i); | |
1549 | ||
1550 | check_xor(); | |
1551 | } | |
9bc89cd8 DW |
1552 | if (count) |
1553 | xor_blocks(count, STRIPE_SIZE, dest, ptr); | |
16a53ecc N |
1554 | if (!nozero) set_bit(R5_UPTODATE, &sh->dev[dd_idx].flags); |
1555 | else clear_bit(R5_UPTODATE, &sh->dev[dd_idx].flags); | |
1556 | } | |
1557 | } | |
1558 | ||
1559 | /* Compute two missing blocks */ | |
1560 | static void compute_block_2(struct stripe_head *sh, int dd_idx1, int dd_idx2) | |
1561 | { | |
f416885e | 1562 | int i, count, disks = sh->disks; |
16a53ecc N |
1563 | int pd_idx = sh->pd_idx; |
1564 | int qd_idx = raid6_next_disk(pd_idx, disks); | |
1565 | int d0_idx = raid6_next_disk(qd_idx, disks); | |
1566 | int faila, failb; | |
1567 | ||
1568 | /* faila and failb are disk numbers relative to d0_idx */ | |
1569 | /* pd_idx become disks-2 and qd_idx become disks-1 */ | |
1570 | faila = (dd_idx1 < d0_idx) ? dd_idx1+(disks-d0_idx) : dd_idx1-d0_idx; | |
1571 | failb = (dd_idx2 < d0_idx) ? dd_idx2+(disks-d0_idx) : dd_idx2-d0_idx; | |
1572 | ||
1573 | BUG_ON(faila == failb); | |
1574 | if ( failb < faila ) { int tmp = faila; faila = failb; failb = tmp; } | |
1575 | ||
45b4233c | 1576 | pr_debug("compute_block_2, stripe %llu, idx %d,%d (%d,%d)\n", |
16a53ecc N |
1577 | (unsigned long long)sh->sector, dd_idx1, dd_idx2, faila, failb); |
1578 | ||
1579 | if ( failb == disks-1 ) { | |
1580 | /* Q disk is one of the missing disks */ | |
1581 | if ( faila == disks-2 ) { | |
1582 | /* Missing P+Q, just recompute */ | |
1583 | compute_parity6(sh, UPDATE_PARITY); | |
1584 | return; | |
1585 | } else { | |
1586 | /* We're missing D+Q; recompute D from P */ | |
1587 | compute_block_1(sh, (dd_idx1 == qd_idx) ? dd_idx2 : dd_idx1, 0); | |
1588 | compute_parity6(sh, UPDATE_PARITY); /* Is this necessary? */ | |
1589 | return; | |
1590 | } | |
1591 | } | |
1592 | ||
1593 | /* We're missing D+P or D+D; build pointer table */ | |
1594 | { | |
1595 | /**** FIX THIS: This could be very bad if disks is close to 256 ****/ | |
1596 | void *ptrs[disks]; | |
1597 | ||
1598 | count = 0; | |
1599 | i = d0_idx; | |
1600 | do { | |
1601 | ptrs[count++] = page_address(sh->dev[i].page); | |
1602 | i = raid6_next_disk(i, disks); | |
1603 | if (i != dd_idx1 && i != dd_idx2 && | |
1604 | !test_bit(R5_UPTODATE, &sh->dev[i].flags)) | |
1605 | printk("compute_2 with missing block %d/%d\n", count, i); | |
1606 | } while ( i != d0_idx ); | |
1607 | ||
1608 | if ( failb == disks-2 ) { | |
1609 | /* We're missing D+P. */ | |
1610 | raid6_datap_recov(disks, STRIPE_SIZE, faila, ptrs); | |
1611 | } else { | |
1612 | /* We're missing D+D. */ | |
1613 | raid6_2data_recov(disks, STRIPE_SIZE, faila, failb, ptrs); | |
1614 | } | |
1615 | ||
1616 | /* Both the above update both missing blocks */ | |
1617 | set_bit(R5_UPTODATE, &sh->dev[dd_idx1].flags); | |
1618 | set_bit(R5_UPTODATE, &sh->dev[dd_idx2].flags); | |
1619 | } | |
1620 | } | |
1621 | ||
600aa109 | 1622 | static void |
1fe797e6 | 1623 | schedule_reconstruction5(struct stripe_head *sh, struct stripe_head_state *s, |
600aa109 | 1624 | int rcw, int expand) |
e33129d8 DW |
1625 | { |
1626 | int i, pd_idx = sh->pd_idx, disks = sh->disks; | |
e33129d8 DW |
1627 | |
1628 | if (rcw) { | |
1629 | /* if we are not expanding this is a proper write request, and | |
1630 | * there will be bios with new data to be drained into the | |
1631 | * stripe cache | |
1632 | */ | |
1633 | if (!expand) { | |
600aa109 DW |
1634 | sh->reconstruct_state = reconstruct_state_drain_run; |
1635 | set_bit(STRIPE_OP_BIODRAIN, &s->ops_request); | |
1636 | } else | |
1637 | sh->reconstruct_state = reconstruct_state_run; | |
16a53ecc | 1638 | |
600aa109 | 1639 | set_bit(STRIPE_OP_POSTXOR, &s->ops_request); |
e33129d8 DW |
1640 | |
1641 | for (i = disks; i--; ) { | |
1642 | struct r5dev *dev = &sh->dev[i]; | |
1643 | ||
1644 | if (dev->towrite) { | |
1645 | set_bit(R5_LOCKED, &dev->flags); | |
d8ee0728 | 1646 | set_bit(R5_Wantdrain, &dev->flags); |
e33129d8 DW |
1647 | if (!expand) |
1648 | clear_bit(R5_UPTODATE, &dev->flags); | |
600aa109 | 1649 | s->locked++; |
e33129d8 DW |
1650 | } |
1651 | } | |
600aa109 | 1652 | if (s->locked + 1 == disks) |
8b3e6cdc DW |
1653 | if (!test_and_set_bit(STRIPE_FULL_WRITE, &sh->state)) |
1654 | atomic_inc(&sh->raid_conf->pending_full_writes); | |
e33129d8 DW |
1655 | } else { |
1656 | BUG_ON(!(test_bit(R5_UPTODATE, &sh->dev[pd_idx].flags) || | |
1657 | test_bit(R5_Wantcompute, &sh->dev[pd_idx].flags))); | |
1658 | ||
d8ee0728 | 1659 | sh->reconstruct_state = reconstruct_state_prexor_drain_run; |
600aa109 DW |
1660 | set_bit(STRIPE_OP_PREXOR, &s->ops_request); |
1661 | set_bit(STRIPE_OP_BIODRAIN, &s->ops_request); | |
1662 | set_bit(STRIPE_OP_POSTXOR, &s->ops_request); | |
e33129d8 DW |
1663 | |
1664 | for (i = disks; i--; ) { | |
1665 | struct r5dev *dev = &sh->dev[i]; | |
1666 | if (i == pd_idx) | |
1667 | continue; | |
1668 | ||
e33129d8 DW |
1669 | if (dev->towrite && |
1670 | (test_bit(R5_UPTODATE, &dev->flags) || | |
d8ee0728 DW |
1671 | test_bit(R5_Wantcompute, &dev->flags))) { |
1672 | set_bit(R5_Wantdrain, &dev->flags); | |
e33129d8 DW |
1673 | set_bit(R5_LOCKED, &dev->flags); |
1674 | clear_bit(R5_UPTODATE, &dev->flags); | |
600aa109 | 1675 | s->locked++; |
e33129d8 DW |
1676 | } |
1677 | } | |
1678 | } | |
1679 | ||
1680 | /* keep the parity disk locked while asynchronous operations | |
1681 | * are in flight | |
1682 | */ | |
1683 | set_bit(R5_LOCKED, &sh->dev[pd_idx].flags); | |
1684 | clear_bit(R5_UPTODATE, &sh->dev[pd_idx].flags); | |
600aa109 | 1685 | s->locked++; |
e33129d8 | 1686 | |
600aa109 | 1687 | pr_debug("%s: stripe %llu locked: %d ops_request: %lx\n", |
e46b272b | 1688 | __func__, (unsigned long long)sh->sector, |
600aa109 | 1689 | s->locked, s->ops_request); |
e33129d8 | 1690 | } |
16a53ecc | 1691 | |
1da177e4 LT |
1692 | /* |
1693 | * Each stripe/dev can have one or more bion attached. | |
16a53ecc | 1694 | * toread/towrite point to the first in a chain. |
1da177e4 LT |
1695 | * The bi_next chain must be in order. |
1696 | */ | |
1697 | static int add_stripe_bio(struct stripe_head *sh, struct bio *bi, int dd_idx, int forwrite) | |
1698 | { | |
1699 | struct bio **bip; | |
1700 | raid5_conf_t *conf = sh->raid_conf; | |
72626685 | 1701 | int firstwrite=0; |
1da177e4 | 1702 | |
45b4233c | 1703 | pr_debug("adding bh b#%llu to stripe s#%llu\n", |
1da177e4 LT |
1704 | (unsigned long long)bi->bi_sector, |
1705 | (unsigned long long)sh->sector); | |
1706 | ||
1707 | ||
1708 | spin_lock(&sh->lock); | |
1709 | spin_lock_irq(&conf->device_lock); | |
72626685 | 1710 | if (forwrite) { |
1da177e4 | 1711 | bip = &sh->dev[dd_idx].towrite; |
72626685 N |
1712 | if (*bip == NULL && sh->dev[dd_idx].written == NULL) |
1713 | firstwrite = 1; | |
1714 | } else | |
1da177e4 LT |
1715 | bip = &sh->dev[dd_idx].toread; |
1716 | while (*bip && (*bip)->bi_sector < bi->bi_sector) { | |
1717 | if ((*bip)->bi_sector + ((*bip)->bi_size >> 9) > bi->bi_sector) | |
1718 | goto overlap; | |
1719 | bip = & (*bip)->bi_next; | |
1720 | } | |
1721 | if (*bip && (*bip)->bi_sector < bi->bi_sector + ((bi->bi_size)>>9)) | |
1722 | goto overlap; | |
1723 | ||
78bafebd | 1724 | BUG_ON(*bip && bi->bi_next && (*bip) != bi->bi_next); |
1da177e4 LT |
1725 | if (*bip) |
1726 | bi->bi_next = *bip; | |
1727 | *bip = bi; | |
1728 | bi->bi_phys_segments ++; | |
1729 | spin_unlock_irq(&conf->device_lock); | |
1730 | spin_unlock(&sh->lock); | |
1731 | ||
45b4233c | 1732 | pr_debug("added bi b#%llu to stripe s#%llu, disk %d.\n", |
1da177e4 LT |
1733 | (unsigned long long)bi->bi_sector, |
1734 | (unsigned long long)sh->sector, dd_idx); | |
1735 | ||
72626685 | 1736 | if (conf->mddev->bitmap && firstwrite) { |
72626685 N |
1737 | bitmap_startwrite(conf->mddev->bitmap, sh->sector, |
1738 | STRIPE_SECTORS, 0); | |
ae3c20cc | 1739 | sh->bm_seq = conf->seq_flush+1; |
72626685 N |
1740 | set_bit(STRIPE_BIT_DELAY, &sh->state); |
1741 | } | |
1742 | ||
1da177e4 LT |
1743 | if (forwrite) { |
1744 | /* check if page is covered */ | |
1745 | sector_t sector = sh->dev[dd_idx].sector; | |
1746 | for (bi=sh->dev[dd_idx].towrite; | |
1747 | sector < sh->dev[dd_idx].sector + STRIPE_SECTORS && | |
1748 | bi && bi->bi_sector <= sector; | |
1749 | bi = r5_next_bio(bi, sh->dev[dd_idx].sector)) { | |
1750 | if (bi->bi_sector + (bi->bi_size>>9) >= sector) | |
1751 | sector = bi->bi_sector + (bi->bi_size>>9); | |
1752 | } | |
1753 | if (sector >= sh->dev[dd_idx].sector + STRIPE_SECTORS) | |
1754 | set_bit(R5_OVERWRITE, &sh->dev[dd_idx].flags); | |
1755 | } | |
1756 | return 1; | |
1757 | ||
1758 | overlap: | |
1759 | set_bit(R5_Overlap, &sh->dev[dd_idx].flags); | |
1760 | spin_unlock_irq(&conf->device_lock); | |
1761 | spin_unlock(&sh->lock); | |
1762 | return 0; | |
1763 | } | |
1764 | ||
29269553 N |
1765 | static void end_reshape(raid5_conf_t *conf); |
1766 | ||
16a53ecc N |
1767 | static int page_is_zero(struct page *p) |
1768 | { | |
1769 | char *a = page_address(p); | |
1770 | return ((*(u32*)a) == 0 && | |
1771 | memcmp(a, a+4, STRIPE_SIZE-4)==0); | |
1772 | } | |
1773 | ||
ccfcc3c1 N |
1774 | static int stripe_to_pdidx(sector_t stripe, raid5_conf_t *conf, int disks) |
1775 | { | |
1776 | int sectors_per_chunk = conf->chunk_size >> 9; | |
ccfcc3c1 | 1777 | int pd_idx, dd_idx; |
2d2063ce CQH |
1778 | int chunk_offset = sector_div(stripe, sectors_per_chunk); |
1779 | ||
b875e531 N |
1780 | raid5_compute_sector(stripe * (disks - conf->max_degraded) |
1781 | *sectors_per_chunk + chunk_offset, | |
1782 | disks, disks - conf->max_degraded, | |
1783 | &dd_idx, &pd_idx, conf); | |
ccfcc3c1 N |
1784 | return pd_idx; |
1785 | } | |
1786 | ||
a4456856 | 1787 | static void |
1fe797e6 | 1788 | handle_failed_stripe(raid5_conf_t *conf, struct stripe_head *sh, |
a4456856 DW |
1789 | struct stripe_head_state *s, int disks, |
1790 | struct bio **return_bi) | |
1791 | { | |
1792 | int i; | |
1793 | for (i = disks; i--; ) { | |
1794 | struct bio *bi; | |
1795 | int bitmap_end = 0; | |
1796 | ||
1797 | if (test_bit(R5_ReadError, &sh->dev[i].flags)) { | |
1798 | mdk_rdev_t *rdev; | |
1799 | rcu_read_lock(); | |
1800 | rdev = rcu_dereference(conf->disks[i].rdev); | |
1801 | if (rdev && test_bit(In_sync, &rdev->flags)) | |
1802 | /* multiple read failures in one stripe */ | |
1803 | md_error(conf->mddev, rdev); | |
1804 | rcu_read_unlock(); | |
1805 | } | |
1806 | spin_lock_irq(&conf->device_lock); | |
1807 | /* fail all writes first */ | |
1808 | bi = sh->dev[i].towrite; | |
1809 | sh->dev[i].towrite = NULL; | |
1810 | if (bi) { | |
1811 | s->to_write--; | |
1812 | bitmap_end = 1; | |
1813 | } | |
1814 | ||
1815 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) | |
1816 | wake_up(&conf->wait_for_overlap); | |
1817 | ||
1818 | while (bi && bi->bi_sector < | |
1819 | sh->dev[i].sector + STRIPE_SECTORS) { | |
1820 | struct bio *nextbi = r5_next_bio(bi, sh->dev[i].sector); | |
1821 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
1822 | if (--bi->bi_phys_segments == 0) { | |
1823 | md_write_end(conf->mddev); | |
1824 | bi->bi_next = *return_bi; | |
1825 | *return_bi = bi; | |
1826 | } | |
1827 | bi = nextbi; | |
1828 | } | |
1829 | /* and fail all 'written' */ | |
1830 | bi = sh->dev[i].written; | |
1831 | sh->dev[i].written = NULL; | |
1832 | if (bi) bitmap_end = 1; | |
1833 | while (bi && bi->bi_sector < | |
1834 | sh->dev[i].sector + STRIPE_SECTORS) { | |
1835 | struct bio *bi2 = r5_next_bio(bi, sh->dev[i].sector); | |
1836 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
1837 | if (--bi->bi_phys_segments == 0) { | |
1838 | md_write_end(conf->mddev); | |
1839 | bi->bi_next = *return_bi; | |
1840 | *return_bi = bi; | |
1841 | } | |
1842 | bi = bi2; | |
1843 | } | |
1844 | ||
b5e98d65 DW |
1845 | /* fail any reads if this device is non-operational and |
1846 | * the data has not reached the cache yet. | |
1847 | */ | |
1848 | if (!test_bit(R5_Wantfill, &sh->dev[i].flags) && | |
1849 | (!test_bit(R5_Insync, &sh->dev[i].flags) || | |
1850 | test_bit(R5_ReadError, &sh->dev[i].flags))) { | |
a4456856 DW |
1851 | bi = sh->dev[i].toread; |
1852 | sh->dev[i].toread = NULL; | |
1853 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) | |
1854 | wake_up(&conf->wait_for_overlap); | |
1855 | if (bi) s->to_read--; | |
1856 | while (bi && bi->bi_sector < | |
1857 | sh->dev[i].sector + STRIPE_SECTORS) { | |
1858 | struct bio *nextbi = | |
1859 | r5_next_bio(bi, sh->dev[i].sector); | |
1860 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
1861 | if (--bi->bi_phys_segments == 0) { | |
1862 | bi->bi_next = *return_bi; | |
1863 | *return_bi = bi; | |
1864 | } | |
1865 | bi = nextbi; | |
1866 | } | |
1867 | } | |
1868 | spin_unlock_irq(&conf->device_lock); | |
1869 | if (bitmap_end) | |
1870 | bitmap_endwrite(conf->mddev->bitmap, sh->sector, | |
1871 | STRIPE_SECTORS, 0, 0); | |
1872 | } | |
1873 | ||
8b3e6cdc DW |
1874 | if (test_and_clear_bit(STRIPE_FULL_WRITE, &sh->state)) |
1875 | if (atomic_dec_and_test(&conf->pending_full_writes)) | |
1876 | md_wakeup_thread(conf->mddev->thread); | |
a4456856 DW |
1877 | } |
1878 | ||
1fe797e6 DW |
1879 | /* fetch_block5 - checks the given member device to see if its data needs |
1880 | * to be read or computed to satisfy a request. | |
1881 | * | |
1882 | * Returns 1 when no more member devices need to be checked, otherwise returns | |
1883 | * 0 to tell the loop in handle_stripe_fill5 to continue | |
f38e1219 | 1884 | */ |
1fe797e6 DW |
1885 | static int fetch_block5(struct stripe_head *sh, struct stripe_head_state *s, |
1886 | int disk_idx, int disks) | |
f38e1219 DW |
1887 | { |
1888 | struct r5dev *dev = &sh->dev[disk_idx]; | |
1889 | struct r5dev *failed_dev = &sh->dev[s->failed_num]; | |
1890 | ||
f38e1219 DW |
1891 | /* is the data in this block needed, and can we get it? */ |
1892 | if (!test_bit(R5_LOCKED, &dev->flags) && | |
1fe797e6 DW |
1893 | !test_bit(R5_UPTODATE, &dev->flags) && |
1894 | (dev->toread || | |
1895 | (dev->towrite && !test_bit(R5_OVERWRITE, &dev->flags)) || | |
1896 | s->syncing || s->expanding || | |
1897 | (s->failed && | |
1898 | (failed_dev->toread || | |
1899 | (failed_dev->towrite && | |
1900 | !test_bit(R5_OVERWRITE, &failed_dev->flags)))))) { | |
976ea8d4 DW |
1901 | /* We would like to get this block, possibly by computing it, |
1902 | * otherwise read it if the backing disk is insync | |
f38e1219 DW |
1903 | */ |
1904 | if ((s->uptodate == disks - 1) && | |
ecc65c9b | 1905 | (s->failed && disk_idx == s->failed_num)) { |
976ea8d4 DW |
1906 | set_bit(STRIPE_COMPUTE_RUN, &sh->state); |
1907 | set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request); | |
f38e1219 DW |
1908 | set_bit(R5_Wantcompute, &dev->flags); |
1909 | sh->ops.target = disk_idx; | |
1910 | s->req_compute = 1; | |
f38e1219 DW |
1911 | /* Careful: from this point on 'uptodate' is in the eye |
1912 | * of raid5_run_ops which services 'compute' operations | |
1913 | * before writes. R5_Wantcompute flags a block that will | |
1914 | * be R5_UPTODATE by the time it is needed for a | |
1915 | * subsequent operation. | |
1916 | */ | |
1917 | s->uptodate++; | |
1fe797e6 | 1918 | return 1; /* uptodate + compute == disks */ |
7a1fc53c | 1919 | } else if (test_bit(R5_Insync, &dev->flags)) { |
f38e1219 DW |
1920 | set_bit(R5_LOCKED, &dev->flags); |
1921 | set_bit(R5_Wantread, &dev->flags); | |
f38e1219 DW |
1922 | s->locked++; |
1923 | pr_debug("Reading block %d (sync=%d)\n", disk_idx, | |
1924 | s->syncing); | |
1925 | } | |
1926 | } | |
1927 | ||
1fe797e6 | 1928 | return 0; |
f38e1219 DW |
1929 | } |
1930 | ||
1fe797e6 DW |
1931 | /** |
1932 | * handle_stripe_fill5 - read or compute data to satisfy pending requests. | |
1933 | */ | |
1934 | static void handle_stripe_fill5(struct stripe_head *sh, | |
a4456856 DW |
1935 | struct stripe_head_state *s, int disks) |
1936 | { | |
1937 | int i; | |
f38e1219 | 1938 | |
f38e1219 DW |
1939 | /* look for blocks to read/compute, skip this if a compute |
1940 | * is already in flight, or if the stripe contents are in the | |
1941 | * midst of changing due to a write | |
1942 | */ | |
976ea8d4 | 1943 | if (!test_bit(STRIPE_COMPUTE_RUN, &sh->state) && !sh->check_state && |
1fe797e6 | 1944 | !sh->reconstruct_state) |
f38e1219 | 1945 | for (i = disks; i--; ) |
1fe797e6 | 1946 | if (fetch_block5(sh, s, i, disks)) |
f38e1219 | 1947 | break; |
a4456856 DW |
1948 | set_bit(STRIPE_HANDLE, &sh->state); |
1949 | } | |
1950 | ||
1fe797e6 | 1951 | static void handle_stripe_fill6(struct stripe_head *sh, |
a4456856 DW |
1952 | struct stripe_head_state *s, struct r6_state *r6s, |
1953 | int disks) | |
1954 | { | |
1955 | int i; | |
1956 | for (i = disks; i--; ) { | |
1957 | struct r5dev *dev = &sh->dev[i]; | |
1958 | if (!test_bit(R5_LOCKED, &dev->flags) && | |
1959 | !test_bit(R5_UPTODATE, &dev->flags) && | |
1960 | (dev->toread || (dev->towrite && | |
1961 | !test_bit(R5_OVERWRITE, &dev->flags)) || | |
1962 | s->syncing || s->expanding || | |
1963 | (s->failed >= 1 && | |
1964 | (sh->dev[r6s->failed_num[0]].toread || | |
1965 | s->to_write)) || | |
1966 | (s->failed >= 2 && | |
1967 | (sh->dev[r6s->failed_num[1]].toread || | |
1968 | s->to_write)))) { | |
1969 | /* we would like to get this block, possibly | |
1970 | * by computing it, but we might not be able to | |
1971 | */ | |
c337869d DW |
1972 | if ((s->uptodate == disks - 1) && |
1973 | (s->failed && (i == r6s->failed_num[0] || | |
1974 | i == r6s->failed_num[1]))) { | |
45b4233c | 1975 | pr_debug("Computing stripe %llu block %d\n", |
a4456856 DW |
1976 | (unsigned long long)sh->sector, i); |
1977 | compute_block_1(sh, i, 0); | |
1978 | s->uptodate++; | |
1979 | } else if ( s->uptodate == disks-2 && s->failed >= 2 ) { | |
1980 | /* Computing 2-failure is *very* expensive; only | |
1981 | * do it if failed >= 2 | |
1982 | */ | |
1983 | int other; | |
1984 | for (other = disks; other--; ) { | |
1985 | if (other == i) | |
1986 | continue; | |
1987 | if (!test_bit(R5_UPTODATE, | |
1988 | &sh->dev[other].flags)) | |
1989 | break; | |
1990 | } | |
1991 | BUG_ON(other < 0); | |
45b4233c | 1992 | pr_debug("Computing stripe %llu blocks %d,%d\n", |
a4456856 DW |
1993 | (unsigned long long)sh->sector, |
1994 | i, other); | |
1995 | compute_block_2(sh, i, other); | |
1996 | s->uptodate += 2; | |
1997 | } else if (test_bit(R5_Insync, &dev->flags)) { | |
1998 | set_bit(R5_LOCKED, &dev->flags); | |
1999 | set_bit(R5_Wantread, &dev->flags); | |
2000 | s->locked++; | |
45b4233c | 2001 | pr_debug("Reading block %d (sync=%d)\n", |
a4456856 DW |
2002 | i, s->syncing); |
2003 | } | |
2004 | } | |
2005 | } | |
2006 | set_bit(STRIPE_HANDLE, &sh->state); | |
2007 | } | |
2008 | ||
2009 | ||
1fe797e6 | 2010 | /* handle_stripe_clean_event |
a4456856 DW |
2011 | * any written block on an uptodate or failed drive can be returned. |
2012 | * Note that if we 'wrote' to a failed drive, it will be UPTODATE, but | |
2013 | * never LOCKED, so we don't need to test 'failed' directly. | |
2014 | */ | |
1fe797e6 | 2015 | static void handle_stripe_clean_event(raid5_conf_t *conf, |
a4456856 DW |
2016 | struct stripe_head *sh, int disks, struct bio **return_bi) |
2017 | { | |
2018 | int i; | |
2019 | struct r5dev *dev; | |
2020 | ||
2021 | for (i = disks; i--; ) | |
2022 | if (sh->dev[i].written) { | |
2023 | dev = &sh->dev[i]; | |
2024 | if (!test_bit(R5_LOCKED, &dev->flags) && | |
2025 | test_bit(R5_UPTODATE, &dev->flags)) { | |
2026 | /* We can return any write requests */ | |
2027 | struct bio *wbi, *wbi2; | |
2028 | int bitmap_end = 0; | |
45b4233c | 2029 | pr_debug("Return write for disc %d\n", i); |
a4456856 DW |
2030 | spin_lock_irq(&conf->device_lock); |
2031 | wbi = dev->written; | |
2032 | dev->written = NULL; | |
2033 | while (wbi && wbi->bi_sector < | |
2034 | dev->sector + STRIPE_SECTORS) { | |
2035 | wbi2 = r5_next_bio(wbi, dev->sector); | |
2036 | if (--wbi->bi_phys_segments == 0) { | |
2037 | md_write_end(conf->mddev); | |
2038 | wbi->bi_next = *return_bi; | |
2039 | *return_bi = wbi; | |
2040 | } | |
2041 | wbi = wbi2; | |
2042 | } | |
2043 | if (dev->towrite == NULL) | |
2044 | bitmap_end = 1; | |
2045 | spin_unlock_irq(&conf->device_lock); | |
2046 | if (bitmap_end) | |
2047 | bitmap_endwrite(conf->mddev->bitmap, | |
2048 | sh->sector, | |
2049 | STRIPE_SECTORS, | |
2050 | !test_bit(STRIPE_DEGRADED, &sh->state), | |
2051 | 0); | |
2052 | } | |
2053 | } | |
8b3e6cdc DW |
2054 | |
2055 | if (test_and_clear_bit(STRIPE_FULL_WRITE, &sh->state)) | |
2056 | if (atomic_dec_and_test(&conf->pending_full_writes)) | |
2057 | md_wakeup_thread(conf->mddev->thread); | |
a4456856 DW |
2058 | } |
2059 | ||
1fe797e6 | 2060 | static void handle_stripe_dirtying5(raid5_conf_t *conf, |
a4456856 DW |
2061 | struct stripe_head *sh, struct stripe_head_state *s, int disks) |
2062 | { | |
2063 | int rmw = 0, rcw = 0, i; | |
2064 | for (i = disks; i--; ) { | |
2065 | /* would I have to read this buffer for read_modify_write */ | |
2066 | struct r5dev *dev = &sh->dev[i]; | |
2067 | if ((dev->towrite || i == sh->pd_idx) && | |
2068 | !test_bit(R5_LOCKED, &dev->flags) && | |
f38e1219 DW |
2069 | !(test_bit(R5_UPTODATE, &dev->flags) || |
2070 | test_bit(R5_Wantcompute, &dev->flags))) { | |
a4456856 DW |
2071 | if (test_bit(R5_Insync, &dev->flags)) |
2072 | rmw++; | |
2073 | else | |
2074 | rmw += 2*disks; /* cannot read it */ | |
2075 | } | |
2076 | /* Would I have to read this buffer for reconstruct_write */ | |
2077 | if (!test_bit(R5_OVERWRITE, &dev->flags) && i != sh->pd_idx && | |
2078 | !test_bit(R5_LOCKED, &dev->flags) && | |
f38e1219 DW |
2079 | !(test_bit(R5_UPTODATE, &dev->flags) || |
2080 | test_bit(R5_Wantcompute, &dev->flags))) { | |
2081 | if (test_bit(R5_Insync, &dev->flags)) rcw++; | |
a4456856 DW |
2082 | else |
2083 | rcw += 2*disks; | |
2084 | } | |
2085 | } | |
45b4233c | 2086 | pr_debug("for sector %llu, rmw=%d rcw=%d\n", |
a4456856 DW |
2087 | (unsigned long long)sh->sector, rmw, rcw); |
2088 | set_bit(STRIPE_HANDLE, &sh->state); | |
2089 | if (rmw < rcw && rmw > 0) | |
2090 | /* prefer read-modify-write, but need to get some data */ | |
2091 | for (i = disks; i--; ) { | |
2092 | struct r5dev *dev = &sh->dev[i]; | |
2093 | if ((dev->towrite || i == sh->pd_idx) && | |
2094 | !test_bit(R5_LOCKED, &dev->flags) && | |
f38e1219 DW |
2095 | !(test_bit(R5_UPTODATE, &dev->flags) || |
2096 | test_bit(R5_Wantcompute, &dev->flags)) && | |
a4456856 DW |
2097 | test_bit(R5_Insync, &dev->flags)) { |
2098 | if ( | |
2099 | test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
45b4233c | 2100 | pr_debug("Read_old block " |
a4456856 DW |
2101 | "%d for r-m-w\n", i); |
2102 | set_bit(R5_LOCKED, &dev->flags); | |
2103 | set_bit(R5_Wantread, &dev->flags); | |
2104 | s->locked++; | |
2105 | } else { | |
2106 | set_bit(STRIPE_DELAYED, &sh->state); | |
2107 | set_bit(STRIPE_HANDLE, &sh->state); | |
2108 | } | |
2109 | } | |
2110 | } | |
2111 | if (rcw <= rmw && rcw > 0) | |
2112 | /* want reconstruct write, but need to get some data */ | |
2113 | for (i = disks; i--; ) { | |
2114 | struct r5dev *dev = &sh->dev[i]; | |
2115 | if (!test_bit(R5_OVERWRITE, &dev->flags) && | |
2116 | i != sh->pd_idx && | |
2117 | !test_bit(R5_LOCKED, &dev->flags) && | |
f38e1219 DW |
2118 | !(test_bit(R5_UPTODATE, &dev->flags) || |
2119 | test_bit(R5_Wantcompute, &dev->flags)) && | |
a4456856 DW |
2120 | test_bit(R5_Insync, &dev->flags)) { |
2121 | if ( | |
2122 | test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
45b4233c | 2123 | pr_debug("Read_old block " |
a4456856 DW |
2124 | "%d for Reconstruct\n", i); |
2125 | set_bit(R5_LOCKED, &dev->flags); | |
2126 | set_bit(R5_Wantread, &dev->flags); | |
2127 | s->locked++; | |
2128 | } else { | |
2129 | set_bit(STRIPE_DELAYED, &sh->state); | |
2130 | set_bit(STRIPE_HANDLE, &sh->state); | |
2131 | } | |
2132 | } | |
2133 | } | |
2134 | /* now if nothing is locked, and if we have enough data, | |
2135 | * we can start a write request | |
2136 | */ | |
f38e1219 DW |
2137 | /* since handle_stripe can be called at any time we need to handle the |
2138 | * case where a compute block operation has been submitted and then a | |
2139 | * subsequent call wants to start a write request. raid5_run_ops only | |
2140 | * handles the case where compute block and postxor are requested | |
2141 | * simultaneously. If this is not the case then new writes need to be | |
2142 | * held off until the compute completes. | |
2143 | */ | |
976ea8d4 DW |
2144 | if ((s->req_compute || !test_bit(STRIPE_COMPUTE_RUN, &sh->state)) && |
2145 | (s->locked == 0 && (rcw == 0 || rmw == 0) && | |
2146 | !test_bit(STRIPE_BIT_DELAY, &sh->state))) | |
1fe797e6 | 2147 | schedule_reconstruction5(sh, s, rcw == 0, 0); |
a4456856 DW |
2148 | } |
2149 | ||
1fe797e6 | 2150 | static void handle_stripe_dirtying6(raid5_conf_t *conf, |
a4456856 DW |
2151 | struct stripe_head *sh, struct stripe_head_state *s, |
2152 | struct r6_state *r6s, int disks) | |
2153 | { | |
2154 | int rcw = 0, must_compute = 0, pd_idx = sh->pd_idx, i; | |
2155 | int qd_idx = r6s->qd_idx; | |
2156 | for (i = disks; i--; ) { | |
2157 | struct r5dev *dev = &sh->dev[i]; | |
2158 | /* Would I have to read this buffer for reconstruct_write */ | |
2159 | if (!test_bit(R5_OVERWRITE, &dev->flags) | |
2160 | && i != pd_idx && i != qd_idx | |
2161 | && (!test_bit(R5_LOCKED, &dev->flags) | |
2162 | ) && | |
2163 | !test_bit(R5_UPTODATE, &dev->flags)) { | |
2164 | if (test_bit(R5_Insync, &dev->flags)) rcw++; | |
2165 | else { | |
45b4233c | 2166 | pr_debug("raid6: must_compute: " |
a4456856 DW |
2167 | "disk %d flags=%#lx\n", i, dev->flags); |
2168 | must_compute++; | |
2169 | } | |
2170 | } | |
2171 | } | |
45b4233c | 2172 | pr_debug("for sector %llu, rcw=%d, must_compute=%d\n", |
a4456856 DW |
2173 | (unsigned long long)sh->sector, rcw, must_compute); |
2174 | set_bit(STRIPE_HANDLE, &sh->state); | |
2175 | ||
2176 | if (rcw > 0) | |
2177 | /* want reconstruct write, but need to get some data */ | |
2178 | for (i = disks; i--; ) { | |
2179 | struct r5dev *dev = &sh->dev[i]; | |
2180 | if (!test_bit(R5_OVERWRITE, &dev->flags) | |
2181 | && !(s->failed == 0 && (i == pd_idx || i == qd_idx)) | |
2182 | && !test_bit(R5_LOCKED, &dev->flags) && | |
2183 | !test_bit(R5_UPTODATE, &dev->flags) && | |
2184 | test_bit(R5_Insync, &dev->flags)) { | |
2185 | if ( | |
2186 | test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
45b4233c | 2187 | pr_debug("Read_old stripe %llu " |
a4456856 DW |
2188 | "block %d for Reconstruct\n", |
2189 | (unsigned long long)sh->sector, i); | |
2190 | set_bit(R5_LOCKED, &dev->flags); | |
2191 | set_bit(R5_Wantread, &dev->flags); | |
2192 | s->locked++; | |
2193 | } else { | |
45b4233c | 2194 | pr_debug("Request delayed stripe %llu " |
a4456856 DW |
2195 | "block %d for Reconstruct\n", |
2196 | (unsigned long long)sh->sector, i); | |
2197 | set_bit(STRIPE_DELAYED, &sh->state); | |
2198 | set_bit(STRIPE_HANDLE, &sh->state); | |
2199 | } | |
2200 | } | |
2201 | } | |
2202 | /* now if nothing is locked, and if we have enough data, we can start a | |
2203 | * write request | |
2204 | */ | |
2205 | if (s->locked == 0 && rcw == 0 && | |
2206 | !test_bit(STRIPE_BIT_DELAY, &sh->state)) { | |
2207 | if (must_compute > 0) { | |
2208 | /* We have failed blocks and need to compute them */ | |
2209 | switch (s->failed) { | |
2210 | case 0: | |
2211 | BUG(); | |
2212 | case 1: | |
2213 | compute_block_1(sh, r6s->failed_num[0], 0); | |
2214 | break; | |
2215 | case 2: | |
2216 | compute_block_2(sh, r6s->failed_num[0], | |
2217 | r6s->failed_num[1]); | |
2218 | break; | |
2219 | default: /* This request should have been failed? */ | |
2220 | BUG(); | |
2221 | } | |
2222 | } | |
2223 | ||
45b4233c | 2224 | pr_debug("Computing parity for stripe %llu\n", |
a4456856 DW |
2225 | (unsigned long long)sh->sector); |
2226 | compute_parity6(sh, RECONSTRUCT_WRITE); | |
2227 | /* now every locked buffer is ready to be written */ | |
2228 | for (i = disks; i--; ) | |
2229 | if (test_bit(R5_LOCKED, &sh->dev[i].flags)) { | |
45b4233c | 2230 | pr_debug("Writing stripe %llu block %d\n", |
a4456856 DW |
2231 | (unsigned long long)sh->sector, i); |
2232 | s->locked++; | |
2233 | set_bit(R5_Wantwrite, &sh->dev[i].flags); | |
2234 | } | |
8b3e6cdc DW |
2235 | if (s->locked == disks) |
2236 | if (!test_and_set_bit(STRIPE_FULL_WRITE, &sh->state)) | |
2237 | atomic_inc(&conf->pending_full_writes); | |
a4456856 DW |
2238 | /* after a RECONSTRUCT_WRITE, the stripe MUST be in-sync */ |
2239 | set_bit(STRIPE_INSYNC, &sh->state); | |
2240 | ||
2241 | if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
2242 | atomic_dec(&conf->preread_active_stripes); | |
2243 | if (atomic_read(&conf->preread_active_stripes) < | |
2244 | IO_THRESHOLD) | |
2245 | md_wakeup_thread(conf->mddev->thread); | |
2246 | } | |
2247 | } | |
2248 | } | |
2249 | ||
2250 | static void handle_parity_checks5(raid5_conf_t *conf, struct stripe_head *sh, | |
2251 | struct stripe_head_state *s, int disks) | |
2252 | { | |
ecc65c9b | 2253 | struct r5dev *dev = NULL; |
bd2ab670 | 2254 | |
a4456856 | 2255 | set_bit(STRIPE_HANDLE, &sh->state); |
e89f8962 | 2256 | |
ecc65c9b DW |
2257 | switch (sh->check_state) { |
2258 | case check_state_idle: | |
2259 | /* start a new check operation if there are no failures */ | |
bd2ab670 | 2260 | if (s->failed == 0) { |
bd2ab670 | 2261 | BUG_ON(s->uptodate != disks); |
ecc65c9b DW |
2262 | sh->check_state = check_state_run; |
2263 | set_bit(STRIPE_OP_CHECK, &s->ops_request); | |
bd2ab670 | 2264 | clear_bit(R5_UPTODATE, &sh->dev[sh->pd_idx].flags); |
bd2ab670 | 2265 | s->uptodate--; |
ecc65c9b | 2266 | break; |
bd2ab670 | 2267 | } |
ecc65c9b DW |
2268 | dev = &sh->dev[s->failed_num]; |
2269 | /* fall through */ | |
2270 | case check_state_compute_result: | |
2271 | sh->check_state = check_state_idle; | |
2272 | if (!dev) | |
2273 | dev = &sh->dev[sh->pd_idx]; | |
2274 | ||
2275 | /* check that a write has not made the stripe insync */ | |
2276 | if (test_bit(STRIPE_INSYNC, &sh->state)) | |
2277 | break; | |
c8894419 | 2278 | |
a4456856 | 2279 | /* either failed parity check, or recovery is happening */ |
a4456856 DW |
2280 | BUG_ON(!test_bit(R5_UPTODATE, &dev->flags)); |
2281 | BUG_ON(s->uptodate != disks); | |
2282 | ||
2283 | set_bit(R5_LOCKED, &dev->flags); | |
ecc65c9b | 2284 | s->locked++; |
a4456856 | 2285 | set_bit(R5_Wantwrite, &dev->flags); |
830ea016 | 2286 | |
a4456856 | 2287 | clear_bit(STRIPE_DEGRADED, &sh->state); |
a4456856 | 2288 | set_bit(STRIPE_INSYNC, &sh->state); |
ecc65c9b DW |
2289 | break; |
2290 | case check_state_run: | |
2291 | break; /* we will be called again upon completion */ | |
2292 | case check_state_check_result: | |
2293 | sh->check_state = check_state_idle; | |
2294 | ||
2295 | /* if a failure occurred during the check operation, leave | |
2296 | * STRIPE_INSYNC not set and let the stripe be handled again | |
2297 | */ | |
2298 | if (s->failed) | |
2299 | break; | |
2300 | ||
2301 | /* handle a successful check operation, if parity is correct | |
2302 | * we are done. Otherwise update the mismatch count and repair | |
2303 | * parity if !MD_RECOVERY_CHECK | |
2304 | */ | |
2305 | if (sh->ops.zero_sum_result == 0) | |
2306 | /* parity is correct (on disc, | |
2307 | * not in buffer any more) | |
2308 | */ | |
2309 | set_bit(STRIPE_INSYNC, &sh->state); | |
2310 | else { | |
2311 | conf->mddev->resync_mismatches += STRIPE_SECTORS; | |
2312 | if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery)) | |
2313 | /* don't try to repair!! */ | |
2314 | set_bit(STRIPE_INSYNC, &sh->state); | |
2315 | else { | |
2316 | sh->check_state = check_state_compute_run; | |
976ea8d4 | 2317 | set_bit(STRIPE_COMPUTE_RUN, &sh->state); |
ecc65c9b DW |
2318 | set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request); |
2319 | set_bit(R5_Wantcompute, | |
2320 | &sh->dev[sh->pd_idx].flags); | |
2321 | sh->ops.target = sh->pd_idx; | |
2322 | s->uptodate++; | |
2323 | } | |
2324 | } | |
2325 | break; | |
2326 | case check_state_compute_run: | |
2327 | break; | |
2328 | default: | |
2329 | printk(KERN_ERR "%s: unknown check_state: %d sector: %llu\n", | |
2330 | __func__, sh->check_state, | |
2331 | (unsigned long long) sh->sector); | |
2332 | BUG(); | |
a4456856 DW |
2333 | } |
2334 | } | |
2335 | ||
2336 | ||
2337 | static void handle_parity_checks6(raid5_conf_t *conf, struct stripe_head *sh, | |
2338 | struct stripe_head_state *s, | |
2339 | struct r6_state *r6s, struct page *tmp_page, | |
2340 | int disks) | |
2341 | { | |
2342 | int update_p = 0, update_q = 0; | |
2343 | struct r5dev *dev; | |
2344 | int pd_idx = sh->pd_idx; | |
2345 | int qd_idx = r6s->qd_idx; | |
2346 | ||
2347 | set_bit(STRIPE_HANDLE, &sh->state); | |
2348 | ||
2349 | BUG_ON(s->failed > 2); | |
2350 | BUG_ON(s->uptodate < disks); | |
2351 | /* Want to check and possibly repair P and Q. | |
2352 | * However there could be one 'failed' device, in which | |
2353 | * case we can only check one of them, possibly using the | |
2354 | * other to generate missing data | |
2355 | */ | |
2356 | ||
2357 | /* If !tmp_page, we cannot do the calculations, | |
2358 | * but as we have set STRIPE_HANDLE, we will soon be called | |
2359 | * by stripe_handle with a tmp_page - just wait until then. | |
2360 | */ | |
2361 | if (tmp_page) { | |
2362 | if (s->failed == r6s->q_failed) { | |
2363 | /* The only possible failed device holds 'Q', so it | |
2364 | * makes sense to check P (If anything else were failed, | |
2365 | * we would have used P to recreate it). | |
2366 | */ | |
2367 | compute_block_1(sh, pd_idx, 1); | |
2368 | if (!page_is_zero(sh->dev[pd_idx].page)) { | |
2369 | compute_block_1(sh, pd_idx, 0); | |
2370 | update_p = 1; | |
2371 | } | |
2372 | } | |
2373 | if (!r6s->q_failed && s->failed < 2) { | |
2374 | /* q is not failed, and we didn't use it to generate | |
2375 | * anything, so it makes sense to check it | |
2376 | */ | |
2377 | memcpy(page_address(tmp_page), | |
2378 | page_address(sh->dev[qd_idx].page), | |
2379 | STRIPE_SIZE); | |
2380 | compute_parity6(sh, UPDATE_PARITY); | |
2381 | if (memcmp(page_address(tmp_page), | |
2382 | page_address(sh->dev[qd_idx].page), | |
2383 | STRIPE_SIZE) != 0) { | |
2384 | clear_bit(STRIPE_INSYNC, &sh->state); | |
2385 | update_q = 1; | |
2386 | } | |
2387 | } | |
2388 | if (update_p || update_q) { | |
2389 | conf->mddev->resync_mismatches += STRIPE_SECTORS; | |
2390 | if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery)) | |
2391 | /* don't try to repair!! */ | |
2392 | update_p = update_q = 0; | |
2393 | } | |
2394 | ||
2395 | /* now write out any block on a failed drive, | |
2396 | * or P or Q if they need it | |
2397 | */ | |
2398 | ||
2399 | if (s->failed == 2) { | |
2400 | dev = &sh->dev[r6s->failed_num[1]]; | |
2401 | s->locked++; | |
2402 | set_bit(R5_LOCKED, &dev->flags); | |
2403 | set_bit(R5_Wantwrite, &dev->flags); | |
2404 | } | |
2405 | if (s->failed >= 1) { | |
2406 | dev = &sh->dev[r6s->failed_num[0]]; | |
2407 | s->locked++; | |
2408 | set_bit(R5_LOCKED, &dev->flags); | |
2409 | set_bit(R5_Wantwrite, &dev->flags); | |
2410 | } | |
2411 | ||
2412 | if (update_p) { | |
2413 | dev = &sh->dev[pd_idx]; | |
2414 | s->locked++; | |
2415 | set_bit(R5_LOCKED, &dev->flags); | |
2416 | set_bit(R5_Wantwrite, &dev->flags); | |
2417 | } | |
2418 | if (update_q) { | |
2419 | dev = &sh->dev[qd_idx]; | |
2420 | s->locked++; | |
2421 | set_bit(R5_LOCKED, &dev->flags); | |
2422 | set_bit(R5_Wantwrite, &dev->flags); | |
2423 | } | |
2424 | clear_bit(STRIPE_DEGRADED, &sh->state); | |
2425 | ||
2426 | set_bit(STRIPE_INSYNC, &sh->state); | |
2427 | } | |
2428 | } | |
2429 | ||
2430 | static void handle_stripe_expansion(raid5_conf_t *conf, struct stripe_head *sh, | |
2431 | struct r6_state *r6s) | |
2432 | { | |
2433 | int i; | |
2434 | ||
2435 | /* We have read all the blocks in this stripe and now we need to | |
2436 | * copy some of them into a target stripe for expand. | |
2437 | */ | |
f0a50d37 | 2438 | struct dma_async_tx_descriptor *tx = NULL; |
a4456856 DW |
2439 | clear_bit(STRIPE_EXPAND_SOURCE, &sh->state); |
2440 | for (i = 0; i < sh->disks; i++) | |
a2e08551 | 2441 | if (i != sh->pd_idx && (!r6s || i != r6s->qd_idx)) { |
a4456856 DW |
2442 | int dd_idx, pd_idx, j; |
2443 | struct stripe_head *sh2; | |
2444 | ||
2445 | sector_t bn = compute_blocknr(sh, i); | |
2446 | sector_t s = raid5_compute_sector(bn, conf->raid_disks, | |
2447 | conf->raid_disks - | |
2448 | conf->max_degraded, &dd_idx, | |
2449 | &pd_idx, conf); | |
2450 | sh2 = get_active_stripe(conf, s, conf->raid_disks, | |
2451 | pd_idx, 1); | |
2452 | if (sh2 == NULL) | |
2453 | /* so far only the early blocks of this stripe | |
2454 | * have been requested. When later blocks | |
2455 | * get requested, we will try again | |
2456 | */ | |
2457 | continue; | |
2458 | if (!test_bit(STRIPE_EXPANDING, &sh2->state) || | |
2459 | test_bit(R5_Expanded, &sh2->dev[dd_idx].flags)) { | |
2460 | /* must have already done this block */ | |
2461 | release_stripe(sh2); | |
2462 | continue; | |
2463 | } | |
f0a50d37 DW |
2464 | |
2465 | /* place all the copies on one channel */ | |
2466 | tx = async_memcpy(sh2->dev[dd_idx].page, | |
2467 | sh->dev[i].page, 0, 0, STRIPE_SIZE, | |
2468 | ASYNC_TX_DEP_ACK, tx, NULL, NULL); | |
2469 | ||
a4456856 DW |
2470 | set_bit(R5_Expanded, &sh2->dev[dd_idx].flags); |
2471 | set_bit(R5_UPTODATE, &sh2->dev[dd_idx].flags); | |
2472 | for (j = 0; j < conf->raid_disks; j++) | |
2473 | if (j != sh2->pd_idx && | |
a2e08551 N |
2474 | (!r6s || j != raid6_next_disk(sh2->pd_idx, |
2475 | sh2->disks)) && | |
a4456856 DW |
2476 | !test_bit(R5_Expanded, &sh2->dev[j].flags)) |
2477 | break; | |
2478 | if (j == conf->raid_disks) { | |
2479 | set_bit(STRIPE_EXPAND_READY, &sh2->state); | |
2480 | set_bit(STRIPE_HANDLE, &sh2->state); | |
2481 | } | |
2482 | release_stripe(sh2); | |
f0a50d37 | 2483 | |
a4456856 | 2484 | } |
a2e08551 N |
2485 | /* done submitting copies, wait for them to complete */ |
2486 | if (tx) { | |
2487 | async_tx_ack(tx); | |
2488 | dma_wait_for_async_tx(tx); | |
2489 | } | |
a4456856 | 2490 | } |
1da177e4 | 2491 | |
6bfe0b49 | 2492 | |
1da177e4 LT |
2493 | /* |
2494 | * handle_stripe - do things to a stripe. | |
2495 | * | |
2496 | * We lock the stripe and then examine the state of various bits | |
2497 | * to see what needs to be done. | |
2498 | * Possible results: | |
2499 | * return some read request which now have data | |
2500 | * return some write requests which are safely on disc | |
2501 | * schedule a read on some buffers | |
2502 | * schedule a write of some buffers | |
2503 | * return confirmation of parity correctness | |
2504 | * | |
1da177e4 LT |
2505 | * buffers are taken off read_list or write_list, and bh_cache buffers |
2506 | * get BH_Lock set before the stripe lock is released. | |
2507 | * | |
2508 | */ | |
a4456856 | 2509 | |
16a53ecc | 2510 | static void handle_stripe5(struct stripe_head *sh) |
1da177e4 LT |
2511 | { |
2512 | raid5_conf_t *conf = sh->raid_conf; | |
a4456856 DW |
2513 | int disks = sh->disks, i; |
2514 | struct bio *return_bi = NULL; | |
2515 | struct stripe_head_state s; | |
1da177e4 | 2516 | struct r5dev *dev; |
6bfe0b49 | 2517 | mdk_rdev_t *blocked_rdev = NULL; |
e0a115e5 | 2518 | int prexor; |
1da177e4 | 2519 | |
a4456856 | 2520 | memset(&s, 0, sizeof(s)); |
600aa109 DW |
2521 | pr_debug("handling stripe %llu, state=%#lx cnt=%d, pd_idx=%d check:%d " |
2522 | "reconstruct:%d\n", (unsigned long long)sh->sector, sh->state, | |
2523 | atomic_read(&sh->count), sh->pd_idx, sh->check_state, | |
2524 | sh->reconstruct_state); | |
1da177e4 LT |
2525 | |
2526 | spin_lock(&sh->lock); | |
2527 | clear_bit(STRIPE_HANDLE, &sh->state); | |
2528 | clear_bit(STRIPE_DELAYED, &sh->state); | |
2529 | ||
a4456856 DW |
2530 | s.syncing = test_bit(STRIPE_SYNCING, &sh->state); |
2531 | s.expanding = test_bit(STRIPE_EXPAND_SOURCE, &sh->state); | |
2532 | s.expanded = test_bit(STRIPE_EXPAND_READY, &sh->state); | |
def6ae26 | 2533 | |
83de75cc | 2534 | /* Now to look around and see what can be done */ |
9910f16a | 2535 | rcu_read_lock(); |
1da177e4 LT |
2536 | for (i=disks; i--; ) { |
2537 | mdk_rdev_t *rdev; | |
a4456856 | 2538 | struct r5dev *dev = &sh->dev[i]; |
1da177e4 | 2539 | clear_bit(R5_Insync, &dev->flags); |
1da177e4 | 2540 | |
b5e98d65 DW |
2541 | pr_debug("check %d: state 0x%lx toread %p read %p write %p " |
2542 | "written %p\n", i, dev->flags, dev->toread, dev->read, | |
2543 | dev->towrite, dev->written); | |
2544 | ||
2545 | /* maybe we can request a biofill operation | |
2546 | * | |
2547 | * new wantfill requests are only permitted while | |
83de75cc | 2548 | * ops_complete_biofill is guaranteed to be inactive |
b5e98d65 DW |
2549 | */ |
2550 | if (test_bit(R5_UPTODATE, &dev->flags) && dev->toread && | |
83de75cc | 2551 | !test_bit(STRIPE_BIOFILL_RUN, &sh->state)) |
b5e98d65 | 2552 | set_bit(R5_Wantfill, &dev->flags); |
1da177e4 LT |
2553 | |
2554 | /* now count some things */ | |
a4456856 DW |
2555 | if (test_bit(R5_LOCKED, &dev->flags)) s.locked++; |
2556 | if (test_bit(R5_UPTODATE, &dev->flags)) s.uptodate++; | |
f38e1219 | 2557 | if (test_bit(R5_Wantcompute, &dev->flags)) s.compute++; |
1da177e4 | 2558 | |
b5e98d65 DW |
2559 | if (test_bit(R5_Wantfill, &dev->flags)) |
2560 | s.to_fill++; | |
2561 | else if (dev->toread) | |
a4456856 | 2562 | s.to_read++; |
1da177e4 | 2563 | if (dev->towrite) { |
a4456856 | 2564 | s.to_write++; |
1da177e4 | 2565 | if (!test_bit(R5_OVERWRITE, &dev->flags)) |
a4456856 | 2566 | s.non_overwrite++; |
1da177e4 | 2567 | } |
a4456856 DW |
2568 | if (dev->written) |
2569 | s.written++; | |
9910f16a | 2570 | rdev = rcu_dereference(conf->disks[i].rdev); |
6bfe0b49 DW |
2571 | if (rdev && unlikely(test_bit(Blocked, &rdev->flags))) { |
2572 | blocked_rdev = rdev; | |
2573 | atomic_inc(&rdev->nr_pending); | |
2574 | break; | |
2575 | } | |
b2d444d7 | 2576 | if (!rdev || !test_bit(In_sync, &rdev->flags)) { |
14f8d26b | 2577 | /* The ReadError flag will just be confusing now */ |
4e5314b5 N |
2578 | clear_bit(R5_ReadError, &dev->flags); |
2579 | clear_bit(R5_ReWrite, &dev->flags); | |
2580 | } | |
b2d444d7 | 2581 | if (!rdev || !test_bit(In_sync, &rdev->flags) |
4e5314b5 | 2582 | || test_bit(R5_ReadError, &dev->flags)) { |
a4456856 DW |
2583 | s.failed++; |
2584 | s.failed_num = i; | |
1da177e4 LT |
2585 | } else |
2586 | set_bit(R5_Insync, &dev->flags); | |
2587 | } | |
9910f16a | 2588 | rcu_read_unlock(); |
b5e98d65 | 2589 | |
6bfe0b49 DW |
2590 | if (unlikely(blocked_rdev)) { |
2591 | set_bit(STRIPE_HANDLE, &sh->state); | |
2592 | goto unlock; | |
2593 | } | |
2594 | ||
83de75cc DW |
2595 | if (s.to_fill && !test_bit(STRIPE_BIOFILL_RUN, &sh->state)) { |
2596 | set_bit(STRIPE_OP_BIOFILL, &s.ops_request); | |
2597 | set_bit(STRIPE_BIOFILL_RUN, &sh->state); | |
2598 | } | |
b5e98d65 | 2599 | |
45b4233c | 2600 | pr_debug("locked=%d uptodate=%d to_read=%d" |
1da177e4 | 2601 | " to_write=%d failed=%d failed_num=%d\n", |
a4456856 DW |
2602 | s.locked, s.uptodate, s.to_read, s.to_write, |
2603 | s.failed, s.failed_num); | |
1da177e4 LT |
2604 | /* check if the array has lost two devices and, if so, some requests might |
2605 | * need to be failed | |
2606 | */ | |
a4456856 | 2607 | if (s.failed > 1 && s.to_read+s.to_write+s.written) |
1fe797e6 | 2608 | handle_failed_stripe(conf, sh, &s, disks, &return_bi); |
a4456856 | 2609 | if (s.failed > 1 && s.syncing) { |
1da177e4 LT |
2610 | md_done_sync(conf->mddev, STRIPE_SECTORS,0); |
2611 | clear_bit(STRIPE_SYNCING, &sh->state); | |
a4456856 | 2612 | s.syncing = 0; |
1da177e4 LT |
2613 | } |
2614 | ||
2615 | /* might be able to return some write requests if the parity block | |
2616 | * is safe, or on a failed drive | |
2617 | */ | |
2618 | dev = &sh->dev[sh->pd_idx]; | |
a4456856 DW |
2619 | if ( s.written && |
2620 | ((test_bit(R5_Insync, &dev->flags) && | |
2621 | !test_bit(R5_LOCKED, &dev->flags) && | |
2622 | test_bit(R5_UPTODATE, &dev->flags)) || | |
2623 | (s.failed == 1 && s.failed_num == sh->pd_idx))) | |
1fe797e6 | 2624 | handle_stripe_clean_event(conf, sh, disks, &return_bi); |
1da177e4 LT |
2625 | |
2626 | /* Now we might consider reading some blocks, either to check/generate | |
2627 | * parity, or to satisfy requests | |
2628 | * or to load a block that is being partially written. | |
2629 | */ | |
a4456856 | 2630 | if (s.to_read || s.non_overwrite || |
976ea8d4 | 2631 | (s.syncing && (s.uptodate + s.compute < disks)) || s.expanding) |
1fe797e6 | 2632 | handle_stripe_fill5(sh, &s, disks); |
1da177e4 | 2633 | |
e33129d8 DW |
2634 | /* Now we check to see if any write operations have recently |
2635 | * completed | |
2636 | */ | |
e0a115e5 | 2637 | prexor = 0; |
d8ee0728 | 2638 | if (sh->reconstruct_state == reconstruct_state_prexor_drain_result) |
e0a115e5 | 2639 | prexor = 1; |
d8ee0728 DW |
2640 | if (sh->reconstruct_state == reconstruct_state_drain_result || |
2641 | sh->reconstruct_state == reconstruct_state_prexor_drain_result) { | |
600aa109 | 2642 | sh->reconstruct_state = reconstruct_state_idle; |
e33129d8 DW |
2643 | |
2644 | /* All the 'written' buffers and the parity block are ready to | |
2645 | * be written back to disk | |
2646 | */ | |
2647 | BUG_ON(!test_bit(R5_UPTODATE, &sh->dev[sh->pd_idx].flags)); | |
2648 | for (i = disks; i--; ) { | |
2649 | dev = &sh->dev[i]; | |
2650 | if (test_bit(R5_LOCKED, &dev->flags) && | |
2651 | (i == sh->pd_idx || dev->written)) { | |
2652 | pr_debug("Writing block %d\n", i); | |
2653 | set_bit(R5_Wantwrite, &dev->flags); | |
e0a115e5 DW |
2654 | if (prexor) |
2655 | continue; | |
e33129d8 DW |
2656 | if (!test_bit(R5_Insync, &dev->flags) || |
2657 | (i == sh->pd_idx && s.failed == 0)) | |
2658 | set_bit(STRIPE_INSYNC, &sh->state); | |
2659 | } | |
2660 | } | |
2661 | if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
2662 | atomic_dec(&conf->preread_active_stripes); | |
2663 | if (atomic_read(&conf->preread_active_stripes) < | |
2664 | IO_THRESHOLD) | |
2665 | md_wakeup_thread(conf->mddev->thread); | |
2666 | } | |
2667 | } | |
2668 | ||
2669 | /* Now to consider new write requests and what else, if anything | |
2670 | * should be read. We do not handle new writes when: | |
2671 | * 1/ A 'write' operation (copy+xor) is already in flight. | |
2672 | * 2/ A 'check' operation is in flight, as it may clobber the parity | |
2673 | * block. | |
2674 | */ | |
600aa109 | 2675 | if (s.to_write && !sh->reconstruct_state && !sh->check_state) |
1fe797e6 | 2676 | handle_stripe_dirtying5(conf, sh, &s, disks); |
1da177e4 LT |
2677 | |
2678 | /* maybe we need to check and possibly fix the parity for this stripe | |
e89f8962 DW |
2679 | * Any reads will already have been scheduled, so we just see if enough |
2680 | * data is available. The parity check is held off while parity | |
2681 | * dependent operations are in flight. | |
1da177e4 | 2682 | */ |
ecc65c9b DW |
2683 | if (sh->check_state || |
2684 | (s.syncing && s.locked == 0 && | |
976ea8d4 | 2685 | !test_bit(STRIPE_COMPUTE_RUN, &sh->state) && |
ecc65c9b | 2686 | !test_bit(STRIPE_INSYNC, &sh->state))) |
a4456856 | 2687 | handle_parity_checks5(conf, sh, &s, disks); |
e89f8962 | 2688 | |
a4456856 | 2689 | if (s.syncing && s.locked == 0 && test_bit(STRIPE_INSYNC, &sh->state)) { |
1da177e4 LT |
2690 | md_done_sync(conf->mddev, STRIPE_SECTORS,1); |
2691 | clear_bit(STRIPE_SYNCING, &sh->state); | |
2692 | } | |
4e5314b5 N |
2693 | |
2694 | /* If the failed drive is just a ReadError, then we might need to progress | |
2695 | * the repair/check process | |
2696 | */ | |
a4456856 DW |
2697 | if (s.failed == 1 && !conf->mddev->ro && |
2698 | test_bit(R5_ReadError, &sh->dev[s.failed_num].flags) | |
2699 | && !test_bit(R5_LOCKED, &sh->dev[s.failed_num].flags) | |
2700 | && test_bit(R5_UPTODATE, &sh->dev[s.failed_num].flags) | |
4e5314b5 | 2701 | ) { |
a4456856 | 2702 | dev = &sh->dev[s.failed_num]; |
4e5314b5 N |
2703 | if (!test_bit(R5_ReWrite, &dev->flags)) { |
2704 | set_bit(R5_Wantwrite, &dev->flags); | |
2705 | set_bit(R5_ReWrite, &dev->flags); | |
2706 | set_bit(R5_LOCKED, &dev->flags); | |
a4456856 | 2707 | s.locked++; |
4e5314b5 N |
2708 | } else { |
2709 | /* let's read it back */ | |
2710 | set_bit(R5_Wantread, &dev->flags); | |
2711 | set_bit(R5_LOCKED, &dev->flags); | |
a4456856 | 2712 | s.locked++; |
4e5314b5 N |
2713 | } |
2714 | } | |
2715 | ||
600aa109 DW |
2716 | /* Finish reconstruct operations initiated by the expansion process */ |
2717 | if (sh->reconstruct_state == reconstruct_state_result) { | |
2718 | sh->reconstruct_state = reconstruct_state_idle; | |
f0a50d37 | 2719 | clear_bit(STRIPE_EXPANDING, &sh->state); |
2b7497f0 | 2720 | for (i = conf->raid_disks; i--; ) |
ccfcc3c1 | 2721 | set_bit(R5_Wantwrite, &sh->dev[i].flags); |
efe31143 NB |
2722 | set_bit(R5_LOCKED, &dev->flags); |
2723 | s.locked++; | |
f0a50d37 DW |
2724 | } |
2725 | ||
2726 | if (s.expanded && test_bit(STRIPE_EXPANDING, &sh->state) && | |
600aa109 | 2727 | !sh->reconstruct_state) { |
f0a50d37 DW |
2728 | /* Need to write out all blocks after computing parity */ |
2729 | sh->disks = conf->raid_disks; | |
2730 | sh->pd_idx = stripe_to_pdidx(sh->sector, conf, | |
2731 | conf->raid_disks); | |
1fe797e6 | 2732 | schedule_reconstruction5(sh, &s, 1, 1); |
600aa109 | 2733 | } else if (s.expanded && !sh->reconstruct_state && s.locked == 0) { |
ccfcc3c1 | 2734 | clear_bit(STRIPE_EXPAND_READY, &sh->state); |
f6705578 | 2735 | atomic_dec(&conf->reshape_stripes); |
ccfcc3c1 N |
2736 | wake_up(&conf->wait_for_overlap); |
2737 | md_done_sync(conf->mddev, STRIPE_SECTORS, 1); | |
2738 | } | |
2739 | ||
0f94e87c | 2740 | if (s.expanding && s.locked == 0 && |
976ea8d4 | 2741 | !test_bit(STRIPE_COMPUTE_RUN, &sh->state)) |
a4456856 | 2742 | handle_stripe_expansion(conf, sh, NULL); |
ccfcc3c1 | 2743 | |
6bfe0b49 | 2744 | unlock: |
1da177e4 LT |
2745 | spin_unlock(&sh->lock); |
2746 | ||
6bfe0b49 DW |
2747 | /* wait for this device to become unblocked */ |
2748 | if (unlikely(blocked_rdev)) | |
2749 | md_wait_for_blocked_rdev(blocked_rdev, conf->mddev); | |
2750 | ||
600aa109 DW |
2751 | if (s.ops_request) |
2752 | raid5_run_ops(sh, s.ops_request); | |
d84e0f10 | 2753 | |
c4e5ac0a | 2754 | ops_run_io(sh, &s); |
1da177e4 | 2755 | |
a4456856 | 2756 | return_io(return_bi); |
1da177e4 LT |
2757 | } |
2758 | ||
16a53ecc | 2759 | static void handle_stripe6(struct stripe_head *sh, struct page *tmp_page) |
1da177e4 | 2760 | { |
16a53ecc | 2761 | raid6_conf_t *conf = sh->raid_conf; |
f416885e | 2762 | int disks = sh->disks; |
a4456856 DW |
2763 | struct bio *return_bi = NULL; |
2764 | int i, pd_idx = sh->pd_idx; | |
2765 | struct stripe_head_state s; | |
2766 | struct r6_state r6s; | |
16a53ecc | 2767 | struct r5dev *dev, *pdev, *qdev; |
6bfe0b49 | 2768 | mdk_rdev_t *blocked_rdev = NULL; |
1da177e4 | 2769 | |
a4456856 | 2770 | r6s.qd_idx = raid6_next_disk(pd_idx, disks); |
45b4233c | 2771 | pr_debug("handling stripe %llu, state=%#lx cnt=%d, " |
a4456856 DW |
2772 | "pd_idx=%d, qd_idx=%d\n", |
2773 | (unsigned long long)sh->sector, sh->state, | |
2774 | atomic_read(&sh->count), pd_idx, r6s.qd_idx); | |
2775 | memset(&s, 0, sizeof(s)); | |
72626685 | 2776 | |
16a53ecc N |
2777 | spin_lock(&sh->lock); |
2778 | clear_bit(STRIPE_HANDLE, &sh->state); | |
2779 | clear_bit(STRIPE_DELAYED, &sh->state); | |
2780 | ||
a4456856 DW |
2781 | s.syncing = test_bit(STRIPE_SYNCING, &sh->state); |
2782 | s.expanding = test_bit(STRIPE_EXPAND_SOURCE, &sh->state); | |
2783 | s.expanded = test_bit(STRIPE_EXPAND_READY, &sh->state); | |
16a53ecc | 2784 | /* Now to look around and see what can be done */ |
1da177e4 LT |
2785 | |
2786 | rcu_read_lock(); | |
16a53ecc N |
2787 | for (i=disks; i--; ) { |
2788 | mdk_rdev_t *rdev; | |
2789 | dev = &sh->dev[i]; | |
2790 | clear_bit(R5_Insync, &dev->flags); | |
1da177e4 | 2791 | |
45b4233c | 2792 | pr_debug("check %d: state 0x%lx read %p write %p written %p\n", |
16a53ecc N |
2793 | i, dev->flags, dev->toread, dev->towrite, dev->written); |
2794 | /* maybe we can reply to a read */ | |
2795 | if (test_bit(R5_UPTODATE, &dev->flags) && dev->toread) { | |
2796 | struct bio *rbi, *rbi2; | |
45b4233c | 2797 | pr_debug("Return read for disc %d\n", i); |
16a53ecc N |
2798 | spin_lock_irq(&conf->device_lock); |
2799 | rbi = dev->toread; | |
2800 | dev->toread = NULL; | |
2801 | if (test_and_clear_bit(R5_Overlap, &dev->flags)) | |
2802 | wake_up(&conf->wait_for_overlap); | |
2803 | spin_unlock_irq(&conf->device_lock); | |
2804 | while (rbi && rbi->bi_sector < dev->sector + STRIPE_SECTORS) { | |
2805 | copy_data(0, rbi, dev->page, dev->sector); | |
2806 | rbi2 = r5_next_bio(rbi, dev->sector); | |
2807 | spin_lock_irq(&conf->device_lock); | |
2808 | if (--rbi->bi_phys_segments == 0) { | |
2809 | rbi->bi_next = return_bi; | |
2810 | return_bi = rbi; | |
2811 | } | |
2812 | spin_unlock_irq(&conf->device_lock); | |
2813 | rbi = rbi2; | |
2814 | } | |
2815 | } | |
1da177e4 | 2816 | |
16a53ecc | 2817 | /* now count some things */ |
a4456856 DW |
2818 | if (test_bit(R5_LOCKED, &dev->flags)) s.locked++; |
2819 | if (test_bit(R5_UPTODATE, &dev->flags)) s.uptodate++; | |
1da177e4 | 2820 | |
16a53ecc | 2821 | |
a4456856 DW |
2822 | if (dev->toread) |
2823 | s.to_read++; | |
16a53ecc | 2824 | if (dev->towrite) { |
a4456856 | 2825 | s.to_write++; |
16a53ecc | 2826 | if (!test_bit(R5_OVERWRITE, &dev->flags)) |
a4456856 | 2827 | s.non_overwrite++; |
16a53ecc | 2828 | } |
a4456856 DW |
2829 | if (dev->written) |
2830 | s.written++; | |
16a53ecc | 2831 | rdev = rcu_dereference(conf->disks[i].rdev); |
6bfe0b49 DW |
2832 | if (rdev && unlikely(test_bit(Blocked, &rdev->flags))) { |
2833 | blocked_rdev = rdev; | |
2834 | atomic_inc(&rdev->nr_pending); | |
2835 | break; | |
2836 | } | |
16a53ecc N |
2837 | if (!rdev || !test_bit(In_sync, &rdev->flags)) { |
2838 | /* The ReadError flag will just be confusing now */ | |
2839 | clear_bit(R5_ReadError, &dev->flags); | |
2840 | clear_bit(R5_ReWrite, &dev->flags); | |
1da177e4 | 2841 | } |
16a53ecc N |
2842 | if (!rdev || !test_bit(In_sync, &rdev->flags) |
2843 | || test_bit(R5_ReadError, &dev->flags)) { | |
a4456856 DW |
2844 | if (s.failed < 2) |
2845 | r6s.failed_num[s.failed] = i; | |
2846 | s.failed++; | |
16a53ecc N |
2847 | } else |
2848 | set_bit(R5_Insync, &dev->flags); | |
1da177e4 LT |
2849 | } |
2850 | rcu_read_unlock(); | |
6bfe0b49 DW |
2851 | |
2852 | if (unlikely(blocked_rdev)) { | |
2853 | set_bit(STRIPE_HANDLE, &sh->state); | |
2854 | goto unlock; | |
2855 | } | |
45b4233c | 2856 | pr_debug("locked=%d uptodate=%d to_read=%d" |
16a53ecc | 2857 | " to_write=%d failed=%d failed_num=%d,%d\n", |
a4456856 DW |
2858 | s.locked, s.uptodate, s.to_read, s.to_write, s.failed, |
2859 | r6s.failed_num[0], r6s.failed_num[1]); | |
2860 | /* check if the array has lost >2 devices and, if so, some requests | |
2861 | * might need to be failed | |
16a53ecc | 2862 | */ |
a4456856 | 2863 | if (s.failed > 2 && s.to_read+s.to_write+s.written) |
1fe797e6 | 2864 | handle_failed_stripe(conf, sh, &s, disks, &return_bi); |
a4456856 | 2865 | if (s.failed > 2 && s.syncing) { |
16a53ecc N |
2866 | md_done_sync(conf->mddev, STRIPE_SECTORS,0); |
2867 | clear_bit(STRIPE_SYNCING, &sh->state); | |
a4456856 | 2868 | s.syncing = 0; |
16a53ecc N |
2869 | } |
2870 | ||
2871 | /* | |
2872 | * might be able to return some write requests if the parity blocks | |
2873 | * are safe, or on a failed drive | |
2874 | */ | |
2875 | pdev = &sh->dev[pd_idx]; | |
a4456856 DW |
2876 | r6s.p_failed = (s.failed >= 1 && r6s.failed_num[0] == pd_idx) |
2877 | || (s.failed >= 2 && r6s.failed_num[1] == pd_idx); | |
2878 | qdev = &sh->dev[r6s.qd_idx]; | |
2879 | r6s.q_failed = (s.failed >= 1 && r6s.failed_num[0] == r6s.qd_idx) | |
2880 | || (s.failed >= 2 && r6s.failed_num[1] == r6s.qd_idx); | |
2881 | ||
2882 | if ( s.written && | |
2883 | ( r6s.p_failed || ((test_bit(R5_Insync, &pdev->flags) | |
16a53ecc | 2884 | && !test_bit(R5_LOCKED, &pdev->flags) |
a4456856 DW |
2885 | && test_bit(R5_UPTODATE, &pdev->flags)))) && |
2886 | ( r6s.q_failed || ((test_bit(R5_Insync, &qdev->flags) | |
16a53ecc | 2887 | && !test_bit(R5_LOCKED, &qdev->flags) |
a4456856 | 2888 | && test_bit(R5_UPTODATE, &qdev->flags))))) |
1fe797e6 | 2889 | handle_stripe_clean_event(conf, sh, disks, &return_bi); |
16a53ecc N |
2890 | |
2891 | /* Now we might consider reading some blocks, either to check/generate | |
2892 | * parity, or to satisfy requests | |
2893 | * or to load a block that is being partially written. | |
2894 | */ | |
a4456856 DW |
2895 | if (s.to_read || s.non_overwrite || (s.to_write && s.failed) || |
2896 | (s.syncing && (s.uptodate < disks)) || s.expanding) | |
1fe797e6 | 2897 | handle_stripe_fill6(sh, &s, &r6s, disks); |
16a53ecc N |
2898 | |
2899 | /* now to consider writing and what else, if anything should be read */ | |
a4456856 | 2900 | if (s.to_write) |
1fe797e6 | 2901 | handle_stripe_dirtying6(conf, sh, &s, &r6s, disks); |
16a53ecc N |
2902 | |
2903 | /* maybe we need to check and possibly fix the parity for this stripe | |
a4456856 DW |
2904 | * Any reads will already have been scheduled, so we just see if enough |
2905 | * data is available | |
16a53ecc | 2906 | */ |
a4456856 DW |
2907 | if (s.syncing && s.locked == 0 && !test_bit(STRIPE_INSYNC, &sh->state)) |
2908 | handle_parity_checks6(conf, sh, &s, &r6s, tmp_page, disks); | |
16a53ecc | 2909 | |
a4456856 | 2910 | if (s.syncing && s.locked == 0 && test_bit(STRIPE_INSYNC, &sh->state)) { |
16a53ecc N |
2911 | md_done_sync(conf->mddev, STRIPE_SECTORS,1); |
2912 | clear_bit(STRIPE_SYNCING, &sh->state); | |
2913 | } | |
2914 | ||
2915 | /* If the failed drives are just a ReadError, then we might need | |
2916 | * to progress the repair/check process | |
2917 | */ | |
a4456856 DW |
2918 | if (s.failed <= 2 && !conf->mddev->ro) |
2919 | for (i = 0; i < s.failed; i++) { | |
2920 | dev = &sh->dev[r6s.failed_num[i]]; | |
16a53ecc N |
2921 | if (test_bit(R5_ReadError, &dev->flags) |
2922 | && !test_bit(R5_LOCKED, &dev->flags) | |
2923 | && test_bit(R5_UPTODATE, &dev->flags) | |
2924 | ) { | |
2925 | if (!test_bit(R5_ReWrite, &dev->flags)) { | |
2926 | set_bit(R5_Wantwrite, &dev->flags); | |
2927 | set_bit(R5_ReWrite, &dev->flags); | |
2928 | set_bit(R5_LOCKED, &dev->flags); | |
2929 | } else { | |
2930 | /* let's read it back */ | |
2931 | set_bit(R5_Wantread, &dev->flags); | |
2932 | set_bit(R5_LOCKED, &dev->flags); | |
2933 | } | |
2934 | } | |
2935 | } | |
f416885e | 2936 | |
a4456856 | 2937 | if (s.expanded && test_bit(STRIPE_EXPANDING, &sh->state)) { |
f416885e N |
2938 | /* Need to write out all blocks after computing P&Q */ |
2939 | sh->disks = conf->raid_disks; | |
2940 | sh->pd_idx = stripe_to_pdidx(sh->sector, conf, | |
2941 | conf->raid_disks); | |
2942 | compute_parity6(sh, RECONSTRUCT_WRITE); | |
2943 | for (i = conf->raid_disks ; i-- ; ) { | |
2944 | set_bit(R5_LOCKED, &sh->dev[i].flags); | |
a4456856 | 2945 | s.locked++; |
f416885e N |
2946 | set_bit(R5_Wantwrite, &sh->dev[i].flags); |
2947 | } | |
2948 | clear_bit(STRIPE_EXPANDING, &sh->state); | |
a4456856 | 2949 | } else if (s.expanded) { |
f416885e N |
2950 | clear_bit(STRIPE_EXPAND_READY, &sh->state); |
2951 | atomic_dec(&conf->reshape_stripes); | |
2952 | wake_up(&conf->wait_for_overlap); | |
2953 | md_done_sync(conf->mddev, STRIPE_SECTORS, 1); | |
2954 | } | |
2955 | ||
0f94e87c | 2956 | if (s.expanding && s.locked == 0 && |
976ea8d4 | 2957 | !test_bit(STRIPE_COMPUTE_RUN, &sh->state)) |
a4456856 | 2958 | handle_stripe_expansion(conf, sh, &r6s); |
f416885e | 2959 | |
6bfe0b49 | 2960 | unlock: |
16a53ecc N |
2961 | spin_unlock(&sh->lock); |
2962 | ||
6bfe0b49 DW |
2963 | /* wait for this device to become unblocked */ |
2964 | if (unlikely(blocked_rdev)) | |
2965 | md_wait_for_blocked_rdev(blocked_rdev, conf->mddev); | |
2966 | ||
f0e43bcd | 2967 | ops_run_io(sh, &s); |
16a53ecc | 2968 | |
f0e43bcd | 2969 | return_io(return_bi); |
16a53ecc N |
2970 | } |
2971 | ||
2972 | static void handle_stripe(struct stripe_head *sh, struct page *tmp_page) | |
2973 | { | |
2974 | if (sh->raid_conf->level == 6) | |
2975 | handle_stripe6(sh, tmp_page); | |
2976 | else | |
2977 | handle_stripe5(sh); | |
2978 | } | |
2979 | ||
2980 | ||
2981 | ||
2982 | static void raid5_activate_delayed(raid5_conf_t *conf) | |
2983 | { | |
2984 | if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD) { | |
2985 | while (!list_empty(&conf->delayed_list)) { | |
2986 | struct list_head *l = conf->delayed_list.next; | |
2987 | struct stripe_head *sh; | |
2988 | sh = list_entry(l, struct stripe_head, lru); | |
2989 | list_del_init(l); | |
2990 | clear_bit(STRIPE_DELAYED, &sh->state); | |
2991 | if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) | |
2992 | atomic_inc(&conf->preread_active_stripes); | |
8b3e6cdc | 2993 | list_add_tail(&sh->lru, &conf->hold_list); |
16a53ecc | 2994 | } |
6ed3003c N |
2995 | } else |
2996 | blk_plug_device(conf->mddev->queue); | |
16a53ecc N |
2997 | } |
2998 | ||
2999 | static void activate_bit_delay(raid5_conf_t *conf) | |
3000 | { | |
3001 | /* device_lock is held */ | |
3002 | struct list_head head; | |
3003 | list_add(&head, &conf->bitmap_list); | |
3004 | list_del_init(&conf->bitmap_list); | |
3005 | while (!list_empty(&head)) { | |
3006 | struct stripe_head *sh = list_entry(head.next, struct stripe_head, lru); | |
3007 | list_del_init(&sh->lru); | |
3008 | atomic_inc(&sh->count); | |
3009 | __release_stripe(conf, sh); | |
3010 | } | |
3011 | } | |
3012 | ||
3013 | static void unplug_slaves(mddev_t *mddev) | |
3014 | { | |
3015 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
3016 | int i; | |
3017 | ||
3018 | rcu_read_lock(); | |
3019 | for (i=0; i<mddev->raid_disks; i++) { | |
3020 | mdk_rdev_t *rdev = rcu_dereference(conf->disks[i].rdev); | |
3021 | if (rdev && !test_bit(Faulty, &rdev->flags) && atomic_read(&rdev->nr_pending)) { | |
165125e1 | 3022 | struct request_queue *r_queue = bdev_get_queue(rdev->bdev); |
16a53ecc N |
3023 | |
3024 | atomic_inc(&rdev->nr_pending); | |
3025 | rcu_read_unlock(); | |
3026 | ||
2ad8b1ef | 3027 | blk_unplug(r_queue); |
16a53ecc N |
3028 | |
3029 | rdev_dec_pending(rdev, mddev); | |
3030 | rcu_read_lock(); | |
3031 | } | |
3032 | } | |
3033 | rcu_read_unlock(); | |
3034 | } | |
3035 | ||
165125e1 | 3036 | static void raid5_unplug_device(struct request_queue *q) |
16a53ecc N |
3037 | { |
3038 | mddev_t *mddev = q->queuedata; | |
3039 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
3040 | unsigned long flags; | |
3041 | ||
3042 | spin_lock_irqsave(&conf->device_lock, flags); | |
3043 | ||
3044 | if (blk_remove_plug(q)) { | |
3045 | conf->seq_flush++; | |
3046 | raid5_activate_delayed(conf); | |
72626685 | 3047 | } |
1da177e4 LT |
3048 | md_wakeup_thread(mddev->thread); |
3049 | ||
3050 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
3051 | ||
3052 | unplug_slaves(mddev); | |
3053 | } | |
3054 | ||
f022b2fd N |
3055 | static int raid5_congested(void *data, int bits) |
3056 | { | |
3057 | mddev_t *mddev = data; | |
3058 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
3059 | ||
3060 | /* No difference between reads and writes. Just check | |
3061 | * how busy the stripe_cache is | |
3062 | */ | |
3063 | if (conf->inactive_blocked) | |
3064 | return 1; | |
3065 | if (conf->quiesce) | |
3066 | return 1; | |
3067 | if (list_empty_careful(&conf->inactive_list)) | |
3068 | return 1; | |
3069 | ||
3070 | return 0; | |
3071 | } | |
3072 | ||
23032a0e RBJ |
3073 | /* We want read requests to align with chunks where possible, |
3074 | * but write requests don't need to. | |
3075 | */ | |
cc371e66 AK |
3076 | static int raid5_mergeable_bvec(struct request_queue *q, |
3077 | struct bvec_merge_data *bvm, | |
3078 | struct bio_vec *biovec) | |
23032a0e RBJ |
3079 | { |
3080 | mddev_t *mddev = q->queuedata; | |
cc371e66 | 3081 | sector_t sector = bvm->bi_sector + get_start_sect(bvm->bi_bdev); |
23032a0e RBJ |
3082 | int max; |
3083 | unsigned int chunk_sectors = mddev->chunk_size >> 9; | |
cc371e66 | 3084 | unsigned int bio_sectors = bvm->bi_size >> 9; |
23032a0e | 3085 | |
cc371e66 | 3086 | if ((bvm->bi_rw & 1) == WRITE) |
23032a0e RBJ |
3087 | return biovec->bv_len; /* always allow writes to be mergeable */ |
3088 | ||
3089 | max = (chunk_sectors - ((sector & (chunk_sectors - 1)) + bio_sectors)) << 9; | |
3090 | if (max < 0) max = 0; | |
3091 | if (max <= biovec->bv_len && bio_sectors == 0) | |
3092 | return biovec->bv_len; | |
3093 | else | |
3094 | return max; | |
3095 | } | |
3096 | ||
f679623f RBJ |
3097 | |
3098 | static int in_chunk_boundary(mddev_t *mddev, struct bio *bio) | |
3099 | { | |
3100 | sector_t sector = bio->bi_sector + get_start_sect(bio->bi_bdev); | |
3101 | unsigned int chunk_sectors = mddev->chunk_size >> 9; | |
3102 | unsigned int bio_sectors = bio->bi_size >> 9; | |
3103 | ||
3104 | return chunk_sectors >= | |
3105 | ((sector & (chunk_sectors - 1)) + bio_sectors); | |
3106 | } | |
3107 | ||
46031f9a RBJ |
3108 | /* |
3109 | * add bio to the retry LIFO ( in O(1) ... we are in interrupt ) | |
3110 | * later sampled by raid5d. | |
3111 | */ | |
3112 | static void add_bio_to_retry(struct bio *bi,raid5_conf_t *conf) | |
3113 | { | |
3114 | unsigned long flags; | |
3115 | ||
3116 | spin_lock_irqsave(&conf->device_lock, flags); | |
3117 | ||
3118 | bi->bi_next = conf->retry_read_aligned_list; | |
3119 | conf->retry_read_aligned_list = bi; | |
3120 | ||
3121 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
3122 | md_wakeup_thread(conf->mddev->thread); | |
3123 | } | |
3124 | ||
3125 | ||
3126 | static struct bio *remove_bio_from_retry(raid5_conf_t *conf) | |
3127 | { | |
3128 | struct bio *bi; | |
3129 | ||
3130 | bi = conf->retry_read_aligned; | |
3131 | if (bi) { | |
3132 | conf->retry_read_aligned = NULL; | |
3133 | return bi; | |
3134 | } | |
3135 | bi = conf->retry_read_aligned_list; | |
3136 | if(bi) { | |
387bb173 | 3137 | conf->retry_read_aligned_list = bi->bi_next; |
46031f9a RBJ |
3138 | bi->bi_next = NULL; |
3139 | bi->bi_phys_segments = 1; /* biased count of active stripes */ | |
3140 | bi->bi_hw_segments = 0; /* count of processed stripes */ | |
3141 | } | |
3142 | ||
3143 | return bi; | |
3144 | } | |
3145 | ||
3146 | ||
f679623f RBJ |
3147 | /* |
3148 | * The "raid5_align_endio" should check if the read succeeded and if it | |
3149 | * did, call bio_endio on the original bio (having bio_put the new bio | |
3150 | * first). | |
3151 | * If the read failed.. | |
3152 | */ | |
6712ecf8 | 3153 | static void raid5_align_endio(struct bio *bi, int error) |
f679623f RBJ |
3154 | { |
3155 | struct bio* raid_bi = bi->bi_private; | |
46031f9a RBJ |
3156 | mddev_t *mddev; |
3157 | raid5_conf_t *conf; | |
3158 | int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags); | |
3159 | mdk_rdev_t *rdev; | |
3160 | ||
f679623f | 3161 | bio_put(bi); |
46031f9a RBJ |
3162 | |
3163 | mddev = raid_bi->bi_bdev->bd_disk->queue->queuedata; | |
3164 | conf = mddev_to_conf(mddev); | |
3165 | rdev = (void*)raid_bi->bi_next; | |
3166 | raid_bi->bi_next = NULL; | |
3167 | ||
3168 | rdev_dec_pending(rdev, conf->mddev); | |
3169 | ||
3170 | if (!error && uptodate) { | |
6712ecf8 | 3171 | bio_endio(raid_bi, 0); |
46031f9a RBJ |
3172 | if (atomic_dec_and_test(&conf->active_aligned_reads)) |
3173 | wake_up(&conf->wait_for_stripe); | |
6712ecf8 | 3174 | return; |
46031f9a RBJ |
3175 | } |
3176 | ||
3177 | ||
45b4233c | 3178 | pr_debug("raid5_align_endio : io error...handing IO for a retry\n"); |
46031f9a RBJ |
3179 | |
3180 | add_bio_to_retry(raid_bi, conf); | |
f679623f RBJ |
3181 | } |
3182 | ||
387bb173 NB |
3183 | static int bio_fits_rdev(struct bio *bi) |
3184 | { | |
165125e1 | 3185 | struct request_queue *q = bdev_get_queue(bi->bi_bdev); |
387bb173 NB |
3186 | |
3187 | if ((bi->bi_size>>9) > q->max_sectors) | |
3188 | return 0; | |
3189 | blk_recount_segments(q, bi); | |
3190 | if (bi->bi_phys_segments > q->max_phys_segments || | |
3191 | bi->bi_hw_segments > q->max_hw_segments) | |
3192 | return 0; | |
3193 | ||
3194 | if (q->merge_bvec_fn) | |
3195 | /* it's too hard to apply the merge_bvec_fn at this stage, | |
3196 | * just just give up | |
3197 | */ | |
3198 | return 0; | |
3199 | ||
3200 | return 1; | |
3201 | } | |
3202 | ||
3203 | ||
165125e1 | 3204 | static int chunk_aligned_read(struct request_queue *q, struct bio * raid_bio) |
f679623f RBJ |
3205 | { |
3206 | mddev_t *mddev = q->queuedata; | |
3207 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
3208 | const unsigned int raid_disks = conf->raid_disks; | |
46031f9a | 3209 | const unsigned int data_disks = raid_disks - conf->max_degraded; |
f679623f RBJ |
3210 | unsigned int dd_idx, pd_idx; |
3211 | struct bio* align_bi; | |
3212 | mdk_rdev_t *rdev; | |
3213 | ||
3214 | if (!in_chunk_boundary(mddev, raid_bio)) { | |
45b4233c | 3215 | pr_debug("chunk_aligned_read : non aligned\n"); |
f679623f RBJ |
3216 | return 0; |
3217 | } | |
3218 | /* | |
3219 | * use bio_clone to make a copy of the bio | |
3220 | */ | |
3221 | align_bi = bio_clone(raid_bio, GFP_NOIO); | |
3222 | if (!align_bi) | |
3223 | return 0; | |
3224 | /* | |
3225 | * set bi_end_io to a new function, and set bi_private to the | |
3226 | * original bio. | |
3227 | */ | |
3228 | align_bi->bi_end_io = raid5_align_endio; | |
3229 | align_bi->bi_private = raid_bio; | |
3230 | /* | |
3231 | * compute position | |
3232 | */ | |
3233 | align_bi->bi_sector = raid5_compute_sector(raid_bio->bi_sector, | |
3234 | raid_disks, | |
3235 | data_disks, | |
3236 | &dd_idx, | |
3237 | &pd_idx, | |
3238 | conf); | |
3239 | ||
3240 | rcu_read_lock(); | |
3241 | rdev = rcu_dereference(conf->disks[dd_idx].rdev); | |
3242 | if (rdev && test_bit(In_sync, &rdev->flags)) { | |
f679623f RBJ |
3243 | atomic_inc(&rdev->nr_pending); |
3244 | rcu_read_unlock(); | |
46031f9a RBJ |
3245 | raid_bio->bi_next = (void*)rdev; |
3246 | align_bi->bi_bdev = rdev->bdev; | |
3247 | align_bi->bi_flags &= ~(1 << BIO_SEG_VALID); | |
3248 | align_bi->bi_sector += rdev->data_offset; | |
3249 | ||
387bb173 NB |
3250 | if (!bio_fits_rdev(align_bi)) { |
3251 | /* too big in some way */ | |
3252 | bio_put(align_bi); | |
3253 | rdev_dec_pending(rdev, mddev); | |
3254 | return 0; | |
3255 | } | |
3256 | ||
46031f9a RBJ |
3257 | spin_lock_irq(&conf->device_lock); |
3258 | wait_event_lock_irq(conf->wait_for_stripe, | |
3259 | conf->quiesce == 0, | |
3260 | conf->device_lock, /* nothing */); | |
3261 | atomic_inc(&conf->active_aligned_reads); | |
3262 | spin_unlock_irq(&conf->device_lock); | |
3263 | ||
f679623f RBJ |
3264 | generic_make_request(align_bi); |
3265 | return 1; | |
3266 | } else { | |
3267 | rcu_read_unlock(); | |
46031f9a | 3268 | bio_put(align_bi); |
f679623f RBJ |
3269 | return 0; |
3270 | } | |
3271 | } | |
3272 | ||
8b3e6cdc DW |
3273 | /* __get_priority_stripe - get the next stripe to process |
3274 | * | |
3275 | * Full stripe writes are allowed to pass preread active stripes up until | |
3276 | * the bypass_threshold is exceeded. In general the bypass_count | |
3277 | * increments when the handle_list is handled before the hold_list; however, it | |
3278 | * will not be incremented when STRIPE_IO_STARTED is sampled set signifying a | |
3279 | * stripe with in flight i/o. The bypass_count will be reset when the | |
3280 | * head of the hold_list has changed, i.e. the head was promoted to the | |
3281 | * handle_list. | |
3282 | */ | |
3283 | static struct stripe_head *__get_priority_stripe(raid5_conf_t *conf) | |
3284 | { | |
3285 | struct stripe_head *sh; | |
3286 | ||
3287 | pr_debug("%s: handle: %s hold: %s full_writes: %d bypass_count: %d\n", | |
3288 | __func__, | |
3289 | list_empty(&conf->handle_list) ? "empty" : "busy", | |
3290 | list_empty(&conf->hold_list) ? "empty" : "busy", | |
3291 | atomic_read(&conf->pending_full_writes), conf->bypass_count); | |
3292 | ||
3293 | if (!list_empty(&conf->handle_list)) { | |
3294 | sh = list_entry(conf->handle_list.next, typeof(*sh), lru); | |
3295 | ||
3296 | if (list_empty(&conf->hold_list)) | |
3297 | conf->bypass_count = 0; | |
3298 | else if (!test_bit(STRIPE_IO_STARTED, &sh->state)) { | |
3299 | if (conf->hold_list.next == conf->last_hold) | |
3300 | conf->bypass_count++; | |
3301 | else { | |
3302 | conf->last_hold = conf->hold_list.next; | |
3303 | conf->bypass_count -= conf->bypass_threshold; | |
3304 | if (conf->bypass_count < 0) | |
3305 | conf->bypass_count = 0; | |
3306 | } | |
3307 | } | |
3308 | } else if (!list_empty(&conf->hold_list) && | |
3309 | ((conf->bypass_threshold && | |
3310 | conf->bypass_count > conf->bypass_threshold) || | |
3311 | atomic_read(&conf->pending_full_writes) == 0)) { | |
3312 | sh = list_entry(conf->hold_list.next, | |
3313 | typeof(*sh), lru); | |
3314 | conf->bypass_count -= conf->bypass_threshold; | |
3315 | if (conf->bypass_count < 0) | |
3316 | conf->bypass_count = 0; | |
3317 | } else | |
3318 | return NULL; | |
3319 | ||
3320 | list_del_init(&sh->lru); | |
3321 | atomic_inc(&sh->count); | |
3322 | BUG_ON(atomic_read(&sh->count) != 1); | |
3323 | return sh; | |
3324 | } | |
f679623f | 3325 | |
165125e1 | 3326 | static int make_request(struct request_queue *q, struct bio * bi) |
1da177e4 LT |
3327 | { |
3328 | mddev_t *mddev = q->queuedata; | |
3329 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
1da177e4 LT |
3330 | unsigned int dd_idx, pd_idx; |
3331 | sector_t new_sector; | |
3332 | sector_t logical_sector, last_sector; | |
3333 | struct stripe_head *sh; | |
a362357b | 3334 | const int rw = bio_data_dir(bi); |
f6344757 | 3335 | int remaining; |
1da177e4 | 3336 | |
e5dcdd80 | 3337 | if (unlikely(bio_barrier(bi))) { |
6712ecf8 | 3338 | bio_endio(bi, -EOPNOTSUPP); |
e5dcdd80 N |
3339 | return 0; |
3340 | } | |
3341 | ||
3d310eb7 | 3342 | md_write_start(mddev, bi); |
06d91a5f | 3343 | |
a362357b JA |
3344 | disk_stat_inc(mddev->gendisk, ios[rw]); |
3345 | disk_stat_add(mddev->gendisk, sectors[rw], bio_sectors(bi)); | |
1da177e4 | 3346 | |
802ba064 | 3347 | if (rw == READ && |
52488615 RBJ |
3348 | mddev->reshape_position == MaxSector && |
3349 | chunk_aligned_read(q,bi)) | |
3350 | return 0; | |
3351 | ||
1da177e4 LT |
3352 | logical_sector = bi->bi_sector & ~((sector_t)STRIPE_SECTORS-1); |
3353 | last_sector = bi->bi_sector + (bi->bi_size>>9); | |
3354 | bi->bi_next = NULL; | |
3355 | bi->bi_phys_segments = 1; /* over-loaded to count active stripes */ | |
06d91a5f | 3356 | |
1da177e4 LT |
3357 | for (;logical_sector < last_sector; logical_sector += STRIPE_SECTORS) { |
3358 | DEFINE_WAIT(w); | |
16a53ecc | 3359 | int disks, data_disks; |
b578d55f | 3360 | |
7ecaa1e6 | 3361 | retry: |
b578d55f | 3362 | prepare_to_wait(&conf->wait_for_overlap, &w, TASK_UNINTERRUPTIBLE); |
7ecaa1e6 N |
3363 | if (likely(conf->expand_progress == MaxSector)) |
3364 | disks = conf->raid_disks; | |
3365 | else { | |
df8e7f76 N |
3366 | /* spinlock is needed as expand_progress may be |
3367 | * 64bit on a 32bit platform, and so it might be | |
3368 | * possible to see a half-updated value | |
3369 | * Ofcourse expand_progress could change after | |
3370 | * the lock is dropped, so once we get a reference | |
3371 | * to the stripe that we think it is, we will have | |
3372 | * to check again. | |
3373 | */ | |
7ecaa1e6 N |
3374 | spin_lock_irq(&conf->device_lock); |
3375 | disks = conf->raid_disks; | |
3376 | if (logical_sector >= conf->expand_progress) | |
3377 | disks = conf->previous_raid_disks; | |
b578d55f N |
3378 | else { |
3379 | if (logical_sector >= conf->expand_lo) { | |
3380 | spin_unlock_irq(&conf->device_lock); | |
3381 | schedule(); | |
3382 | goto retry; | |
3383 | } | |
3384 | } | |
7ecaa1e6 N |
3385 | spin_unlock_irq(&conf->device_lock); |
3386 | } | |
16a53ecc N |
3387 | data_disks = disks - conf->max_degraded; |
3388 | ||
3389 | new_sector = raid5_compute_sector(logical_sector, disks, data_disks, | |
7ecaa1e6 | 3390 | &dd_idx, &pd_idx, conf); |
45b4233c | 3391 | pr_debug("raid5: make_request, sector %llu logical %llu\n", |
1da177e4 LT |
3392 | (unsigned long long)new_sector, |
3393 | (unsigned long long)logical_sector); | |
3394 | ||
7ecaa1e6 | 3395 | sh = get_active_stripe(conf, new_sector, disks, pd_idx, (bi->bi_rw&RWA_MASK)); |
1da177e4 | 3396 | if (sh) { |
7ecaa1e6 N |
3397 | if (unlikely(conf->expand_progress != MaxSector)) { |
3398 | /* expansion might have moved on while waiting for a | |
df8e7f76 N |
3399 | * stripe, so we must do the range check again. |
3400 | * Expansion could still move past after this | |
3401 | * test, but as we are holding a reference to | |
3402 | * 'sh', we know that if that happens, | |
3403 | * STRIPE_EXPANDING will get set and the expansion | |
3404 | * won't proceed until we finish with the stripe. | |
7ecaa1e6 N |
3405 | */ |
3406 | int must_retry = 0; | |
3407 | spin_lock_irq(&conf->device_lock); | |
3408 | if (logical_sector < conf->expand_progress && | |
3409 | disks == conf->previous_raid_disks) | |
3410 | /* mismatch, need to try again */ | |
3411 | must_retry = 1; | |
3412 | spin_unlock_irq(&conf->device_lock); | |
3413 | if (must_retry) { | |
3414 | release_stripe(sh); | |
3415 | goto retry; | |
3416 | } | |
3417 | } | |
e464eafd N |
3418 | /* FIXME what if we get a false positive because these |
3419 | * are being updated. | |
3420 | */ | |
3421 | if (logical_sector >= mddev->suspend_lo && | |
3422 | logical_sector < mddev->suspend_hi) { | |
3423 | release_stripe(sh); | |
3424 | schedule(); | |
3425 | goto retry; | |
3426 | } | |
7ecaa1e6 N |
3427 | |
3428 | if (test_bit(STRIPE_EXPANDING, &sh->state) || | |
3429 | !add_stripe_bio(sh, bi, dd_idx, (bi->bi_rw&RW_MASK))) { | |
3430 | /* Stripe is busy expanding or | |
3431 | * add failed due to overlap. Flush everything | |
1da177e4 LT |
3432 | * and wait a while |
3433 | */ | |
3434 | raid5_unplug_device(mddev->queue); | |
3435 | release_stripe(sh); | |
3436 | schedule(); | |
3437 | goto retry; | |
3438 | } | |
3439 | finish_wait(&conf->wait_for_overlap, &w); | |
6ed3003c N |
3440 | set_bit(STRIPE_HANDLE, &sh->state); |
3441 | clear_bit(STRIPE_DELAYED, &sh->state); | |
1da177e4 | 3442 | release_stripe(sh); |
1da177e4 LT |
3443 | } else { |
3444 | /* cannot get stripe for read-ahead, just give-up */ | |
3445 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
3446 | finish_wait(&conf->wait_for_overlap, &w); | |
3447 | break; | |
3448 | } | |
3449 | ||
3450 | } | |
3451 | spin_lock_irq(&conf->device_lock); | |
f6344757 N |
3452 | remaining = --bi->bi_phys_segments; |
3453 | spin_unlock_irq(&conf->device_lock); | |
3454 | if (remaining == 0) { | |
1da177e4 | 3455 | |
16a53ecc | 3456 | if ( rw == WRITE ) |
1da177e4 | 3457 | md_write_end(mddev); |
6712ecf8 | 3458 | |
0e13fe23 | 3459 | bio_endio(bi, 0); |
1da177e4 | 3460 | } |
1da177e4 LT |
3461 | return 0; |
3462 | } | |
3463 | ||
52c03291 | 3464 | static sector_t reshape_request(mddev_t *mddev, sector_t sector_nr, int *skipped) |
1da177e4 | 3465 | { |
52c03291 N |
3466 | /* reshaping is quite different to recovery/resync so it is |
3467 | * handled quite separately ... here. | |
3468 | * | |
3469 | * On each call to sync_request, we gather one chunk worth of | |
3470 | * destination stripes and flag them as expanding. | |
3471 | * Then we find all the source stripes and request reads. | |
3472 | * As the reads complete, handle_stripe will copy the data | |
3473 | * into the destination stripe and release that stripe. | |
3474 | */ | |
1da177e4 LT |
3475 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; |
3476 | struct stripe_head *sh; | |
ccfcc3c1 N |
3477 | int pd_idx; |
3478 | sector_t first_sector, last_sector; | |
f416885e N |
3479 | int raid_disks = conf->previous_raid_disks; |
3480 | int data_disks = raid_disks - conf->max_degraded; | |
3481 | int new_data_disks = conf->raid_disks - conf->max_degraded; | |
52c03291 N |
3482 | int i; |
3483 | int dd_idx; | |
3484 | sector_t writepos, safepos, gap; | |
3485 | ||
3486 | if (sector_nr == 0 && | |
3487 | conf->expand_progress != 0) { | |
3488 | /* restarting in the middle, skip the initial sectors */ | |
3489 | sector_nr = conf->expand_progress; | |
f416885e | 3490 | sector_div(sector_nr, new_data_disks); |
52c03291 N |
3491 | *skipped = 1; |
3492 | return sector_nr; | |
3493 | } | |
3494 | ||
3495 | /* we update the metadata when there is more than 3Meg | |
3496 | * in the block range (that is rather arbitrary, should | |
3497 | * probably be time based) or when the data about to be | |
3498 | * copied would over-write the source of the data at | |
3499 | * the front of the range. | |
3500 | * i.e. one new_stripe forward from expand_progress new_maps | |
3501 | * to after where expand_lo old_maps to | |
3502 | */ | |
3503 | writepos = conf->expand_progress + | |
f416885e N |
3504 | conf->chunk_size/512*(new_data_disks); |
3505 | sector_div(writepos, new_data_disks); | |
52c03291 | 3506 | safepos = conf->expand_lo; |
f416885e | 3507 | sector_div(safepos, data_disks); |
52c03291 N |
3508 | gap = conf->expand_progress - conf->expand_lo; |
3509 | ||
3510 | if (writepos >= safepos || | |
f416885e | 3511 | gap > (new_data_disks)*3000*2 /*3Meg*/) { |
52c03291 N |
3512 | /* Cannot proceed until we've updated the superblock... */ |
3513 | wait_event(conf->wait_for_overlap, | |
3514 | atomic_read(&conf->reshape_stripes)==0); | |
3515 | mddev->reshape_position = conf->expand_progress; | |
850b2b42 | 3516 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
52c03291 | 3517 | md_wakeup_thread(mddev->thread); |
850b2b42 | 3518 | wait_event(mddev->sb_wait, mddev->flags == 0 || |
52c03291 N |
3519 | kthread_should_stop()); |
3520 | spin_lock_irq(&conf->device_lock); | |
3521 | conf->expand_lo = mddev->reshape_position; | |
3522 | spin_unlock_irq(&conf->device_lock); | |
3523 | wake_up(&conf->wait_for_overlap); | |
3524 | } | |
3525 | ||
3526 | for (i=0; i < conf->chunk_size/512; i+= STRIPE_SECTORS) { | |
3527 | int j; | |
3528 | int skipped = 0; | |
3529 | pd_idx = stripe_to_pdidx(sector_nr+i, conf, conf->raid_disks); | |
3530 | sh = get_active_stripe(conf, sector_nr+i, | |
3531 | conf->raid_disks, pd_idx, 0); | |
3532 | set_bit(STRIPE_EXPANDING, &sh->state); | |
3533 | atomic_inc(&conf->reshape_stripes); | |
3534 | /* If any of this stripe is beyond the end of the old | |
3535 | * array, then we need to zero those blocks | |
3536 | */ | |
3537 | for (j=sh->disks; j--;) { | |
3538 | sector_t s; | |
3539 | if (j == sh->pd_idx) | |
3540 | continue; | |
f416885e N |
3541 | if (conf->level == 6 && |
3542 | j == raid6_next_disk(sh->pd_idx, sh->disks)) | |
3543 | continue; | |
52c03291 | 3544 | s = compute_blocknr(sh, j); |
f233ea5c | 3545 | if (s < mddev->array_sectors) { |
52c03291 N |
3546 | skipped = 1; |
3547 | continue; | |
3548 | } | |
3549 | memset(page_address(sh->dev[j].page), 0, STRIPE_SIZE); | |
3550 | set_bit(R5_Expanded, &sh->dev[j].flags); | |
3551 | set_bit(R5_UPTODATE, &sh->dev[j].flags); | |
3552 | } | |
3553 | if (!skipped) { | |
3554 | set_bit(STRIPE_EXPAND_READY, &sh->state); | |
3555 | set_bit(STRIPE_HANDLE, &sh->state); | |
3556 | } | |
3557 | release_stripe(sh); | |
3558 | } | |
3559 | spin_lock_irq(&conf->device_lock); | |
6d3baf2e | 3560 | conf->expand_progress = (sector_nr + i) * new_data_disks; |
52c03291 N |
3561 | spin_unlock_irq(&conf->device_lock); |
3562 | /* Ok, those stripe are ready. We can start scheduling | |
3563 | * reads on the source stripes. | |
3564 | * The source stripes are determined by mapping the first and last | |
3565 | * block on the destination stripes. | |
3566 | */ | |
52c03291 | 3567 | first_sector = |
f416885e | 3568 | raid5_compute_sector(sector_nr*(new_data_disks), |
52c03291 N |
3569 | raid_disks, data_disks, |
3570 | &dd_idx, &pd_idx, conf); | |
3571 | last_sector = | |
3572 | raid5_compute_sector((sector_nr+conf->chunk_size/512) | |
f416885e | 3573 | *(new_data_disks) -1, |
52c03291 N |
3574 | raid_disks, data_disks, |
3575 | &dd_idx, &pd_idx, conf); | |
3576 | if (last_sector >= (mddev->size<<1)) | |
3577 | last_sector = (mddev->size<<1)-1; | |
3578 | while (first_sector <= last_sector) { | |
f416885e N |
3579 | pd_idx = stripe_to_pdidx(first_sector, conf, |
3580 | conf->previous_raid_disks); | |
52c03291 N |
3581 | sh = get_active_stripe(conf, first_sector, |
3582 | conf->previous_raid_disks, pd_idx, 0); | |
3583 | set_bit(STRIPE_EXPAND_SOURCE, &sh->state); | |
3584 | set_bit(STRIPE_HANDLE, &sh->state); | |
3585 | release_stripe(sh); | |
3586 | first_sector += STRIPE_SECTORS; | |
3587 | } | |
c6207277 N |
3588 | /* If this takes us to the resync_max point where we have to pause, |
3589 | * then we need to write out the superblock. | |
3590 | */ | |
3591 | sector_nr += conf->chunk_size>>9; | |
3592 | if (sector_nr >= mddev->resync_max) { | |
3593 | /* Cannot proceed until we've updated the superblock... */ | |
3594 | wait_event(conf->wait_for_overlap, | |
3595 | atomic_read(&conf->reshape_stripes) == 0); | |
3596 | mddev->reshape_position = conf->expand_progress; | |
3597 | set_bit(MD_CHANGE_DEVS, &mddev->flags); | |
3598 | md_wakeup_thread(mddev->thread); | |
3599 | wait_event(mddev->sb_wait, | |
3600 | !test_bit(MD_CHANGE_DEVS, &mddev->flags) | |
3601 | || kthread_should_stop()); | |
3602 | spin_lock_irq(&conf->device_lock); | |
3603 | conf->expand_lo = mddev->reshape_position; | |
3604 | spin_unlock_irq(&conf->device_lock); | |
3605 | wake_up(&conf->wait_for_overlap); | |
3606 | } | |
52c03291 N |
3607 | return conf->chunk_size>>9; |
3608 | } | |
3609 | ||
3610 | /* FIXME go_faster isn't used */ | |
3611 | static inline sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, int go_faster) | |
3612 | { | |
3613 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; | |
3614 | struct stripe_head *sh; | |
3615 | int pd_idx; | |
1da177e4 | 3616 | int raid_disks = conf->raid_disks; |
72626685 N |
3617 | sector_t max_sector = mddev->size << 1; |
3618 | int sync_blocks; | |
16a53ecc N |
3619 | int still_degraded = 0; |
3620 | int i; | |
1da177e4 | 3621 | |
72626685 | 3622 | if (sector_nr >= max_sector) { |
1da177e4 LT |
3623 | /* just being told to finish up .. nothing much to do */ |
3624 | unplug_slaves(mddev); | |
29269553 N |
3625 | if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) { |
3626 | end_reshape(conf); | |
3627 | return 0; | |
3628 | } | |
72626685 N |
3629 | |
3630 | if (mddev->curr_resync < max_sector) /* aborted */ | |
3631 | bitmap_end_sync(mddev->bitmap, mddev->curr_resync, | |
3632 | &sync_blocks, 1); | |
16a53ecc | 3633 | else /* completed sync */ |
72626685 N |
3634 | conf->fullsync = 0; |
3635 | bitmap_close_sync(mddev->bitmap); | |
3636 | ||
1da177e4 LT |
3637 | return 0; |
3638 | } | |
ccfcc3c1 | 3639 | |
52c03291 N |
3640 | if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) |
3641 | return reshape_request(mddev, sector_nr, skipped); | |
f6705578 | 3642 | |
c6207277 N |
3643 | /* No need to check resync_max as we never do more than one |
3644 | * stripe, and as resync_max will always be on a chunk boundary, | |
3645 | * if the check in md_do_sync didn't fire, there is no chance | |
3646 | * of overstepping resync_max here | |
3647 | */ | |
3648 | ||
16a53ecc | 3649 | /* if there is too many failed drives and we are trying |
1da177e4 LT |
3650 | * to resync, then assert that we are finished, because there is |
3651 | * nothing we can do. | |
3652 | */ | |
3285edf1 | 3653 | if (mddev->degraded >= conf->max_degraded && |
16a53ecc | 3654 | test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) { |
57afd89f N |
3655 | sector_t rv = (mddev->size << 1) - sector_nr; |
3656 | *skipped = 1; | |
1da177e4 LT |
3657 | return rv; |
3658 | } | |
72626685 | 3659 | if (!bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, 1) && |
3855ad9f | 3660 | !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) && |
72626685 N |
3661 | !conf->fullsync && sync_blocks >= STRIPE_SECTORS) { |
3662 | /* we can skip this block, and probably more */ | |
3663 | sync_blocks /= STRIPE_SECTORS; | |
3664 | *skipped = 1; | |
3665 | return sync_blocks * STRIPE_SECTORS; /* keep things rounded to whole stripes */ | |
3666 | } | |
1da177e4 | 3667 | |
b47490c9 N |
3668 | |
3669 | bitmap_cond_end_sync(mddev->bitmap, sector_nr); | |
3670 | ||
ccfcc3c1 | 3671 | pd_idx = stripe_to_pdidx(sector_nr, conf, raid_disks); |
7ecaa1e6 | 3672 | sh = get_active_stripe(conf, sector_nr, raid_disks, pd_idx, 1); |
1da177e4 | 3673 | if (sh == NULL) { |
7ecaa1e6 | 3674 | sh = get_active_stripe(conf, sector_nr, raid_disks, pd_idx, 0); |
1da177e4 | 3675 | /* make sure we don't swamp the stripe cache if someone else |
16a53ecc | 3676 | * is trying to get access |
1da177e4 | 3677 | */ |
66c006a5 | 3678 | schedule_timeout_uninterruptible(1); |
1da177e4 | 3679 | } |
16a53ecc N |
3680 | /* Need to check if array will still be degraded after recovery/resync |
3681 | * We don't need to check the 'failed' flag as when that gets set, | |
3682 | * recovery aborts. | |
3683 | */ | |
3684 | for (i=0; i<mddev->raid_disks; i++) | |
3685 | if (conf->disks[i].rdev == NULL) | |
3686 | still_degraded = 1; | |
3687 | ||
3688 | bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, still_degraded); | |
3689 | ||
3690 | spin_lock(&sh->lock); | |
1da177e4 LT |
3691 | set_bit(STRIPE_SYNCING, &sh->state); |
3692 | clear_bit(STRIPE_INSYNC, &sh->state); | |
3693 | spin_unlock(&sh->lock); | |
3694 | ||
16a53ecc | 3695 | handle_stripe(sh, NULL); |
1da177e4 LT |
3696 | release_stripe(sh); |
3697 | ||
3698 | return STRIPE_SECTORS; | |
3699 | } | |
3700 | ||
46031f9a RBJ |
3701 | static int retry_aligned_read(raid5_conf_t *conf, struct bio *raid_bio) |
3702 | { | |
3703 | /* We may not be able to submit a whole bio at once as there | |
3704 | * may not be enough stripe_heads available. | |
3705 | * We cannot pre-allocate enough stripe_heads as we may need | |
3706 | * more than exist in the cache (if we allow ever large chunks). | |
3707 | * So we do one stripe head at a time and record in | |
3708 | * ->bi_hw_segments how many have been done. | |
3709 | * | |
3710 | * We *know* that this entire raid_bio is in one chunk, so | |
3711 | * it will be only one 'dd_idx' and only need one call to raid5_compute_sector. | |
3712 | */ | |
3713 | struct stripe_head *sh; | |
3714 | int dd_idx, pd_idx; | |
3715 | sector_t sector, logical_sector, last_sector; | |
3716 | int scnt = 0; | |
3717 | int remaining; | |
3718 | int handled = 0; | |
3719 | ||
3720 | logical_sector = raid_bio->bi_sector & ~((sector_t)STRIPE_SECTORS-1); | |
3721 | sector = raid5_compute_sector( logical_sector, | |
3722 | conf->raid_disks, | |
3723 | conf->raid_disks - conf->max_degraded, | |
3724 | &dd_idx, | |
3725 | &pd_idx, | |
3726 | conf); | |
3727 | last_sector = raid_bio->bi_sector + (raid_bio->bi_size>>9); | |
3728 | ||
3729 | for (; logical_sector < last_sector; | |
387bb173 NB |
3730 | logical_sector += STRIPE_SECTORS, |
3731 | sector += STRIPE_SECTORS, | |
3732 | scnt++) { | |
46031f9a RBJ |
3733 | |
3734 | if (scnt < raid_bio->bi_hw_segments) | |
3735 | /* already done this stripe */ | |
3736 | continue; | |
3737 | ||
3738 | sh = get_active_stripe(conf, sector, conf->raid_disks, pd_idx, 1); | |
3739 | ||
3740 | if (!sh) { | |
3741 | /* failed to get a stripe - must wait */ | |
3742 | raid_bio->bi_hw_segments = scnt; | |
3743 | conf->retry_read_aligned = raid_bio; | |
3744 | return handled; | |
3745 | } | |
3746 | ||
3747 | set_bit(R5_ReadError, &sh->dev[dd_idx].flags); | |
387bb173 NB |
3748 | if (!add_stripe_bio(sh, raid_bio, dd_idx, 0)) { |
3749 | release_stripe(sh); | |
3750 | raid_bio->bi_hw_segments = scnt; | |
3751 | conf->retry_read_aligned = raid_bio; | |
3752 | return handled; | |
3753 | } | |
3754 | ||
46031f9a RBJ |
3755 | handle_stripe(sh, NULL); |
3756 | release_stripe(sh); | |
3757 | handled++; | |
3758 | } | |
3759 | spin_lock_irq(&conf->device_lock); | |
3760 | remaining = --raid_bio->bi_phys_segments; | |
3761 | spin_unlock_irq(&conf->device_lock); | |
0e13fe23 NB |
3762 | if (remaining == 0) |
3763 | bio_endio(raid_bio, 0); | |
46031f9a RBJ |
3764 | if (atomic_dec_and_test(&conf->active_aligned_reads)) |
3765 | wake_up(&conf->wait_for_stripe); | |
3766 | return handled; | |
3767 | } | |
3768 | ||
3769 | ||
3770 | ||
1da177e4 LT |
3771 | /* |
3772 | * This is our raid5 kernel thread. | |
3773 | * | |
3774 | * We scan the hash table for stripes which can be handled now. | |
3775 | * During the scan, completed stripes are saved for us by the interrupt | |
3776 | * handler, so that they will not have to wait for our next wakeup. | |
3777 | */ | |
6ed3003c | 3778 | static void raid5d(mddev_t *mddev) |
1da177e4 LT |
3779 | { |
3780 | struct stripe_head *sh; | |
3781 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
3782 | int handled; | |
3783 | ||
45b4233c | 3784 | pr_debug("+++ raid5d active\n"); |
1da177e4 LT |
3785 | |
3786 | md_check_recovery(mddev); | |
1da177e4 LT |
3787 | |
3788 | handled = 0; | |
3789 | spin_lock_irq(&conf->device_lock); | |
3790 | while (1) { | |
46031f9a | 3791 | struct bio *bio; |
1da177e4 | 3792 | |
ae3c20cc | 3793 | if (conf->seq_flush != conf->seq_write) { |
72626685 | 3794 | int seq = conf->seq_flush; |
700e432d | 3795 | spin_unlock_irq(&conf->device_lock); |
72626685 | 3796 | bitmap_unplug(mddev->bitmap); |
700e432d | 3797 | spin_lock_irq(&conf->device_lock); |
72626685 N |
3798 | conf->seq_write = seq; |
3799 | activate_bit_delay(conf); | |
3800 | } | |
3801 | ||
46031f9a RBJ |
3802 | while ((bio = remove_bio_from_retry(conf))) { |
3803 | int ok; | |
3804 | spin_unlock_irq(&conf->device_lock); | |
3805 | ok = retry_aligned_read(conf, bio); | |
3806 | spin_lock_irq(&conf->device_lock); | |
3807 | if (!ok) | |
3808 | break; | |
3809 | handled++; | |
3810 | } | |
3811 | ||
8b3e6cdc DW |
3812 | sh = __get_priority_stripe(conf); |
3813 | ||
3814 | if (!sh) { | |
d84e0f10 | 3815 | async_tx_issue_pending_all(); |
1da177e4 | 3816 | break; |
d84e0f10 | 3817 | } |
1da177e4 LT |
3818 | spin_unlock_irq(&conf->device_lock); |
3819 | ||
3820 | handled++; | |
16a53ecc | 3821 | handle_stripe(sh, conf->spare_page); |
1da177e4 LT |
3822 | release_stripe(sh); |
3823 | ||
3824 | spin_lock_irq(&conf->device_lock); | |
3825 | } | |
45b4233c | 3826 | pr_debug("%d stripes handled\n", handled); |
1da177e4 LT |
3827 | |
3828 | spin_unlock_irq(&conf->device_lock); | |
3829 | ||
3830 | unplug_slaves(mddev); | |
3831 | ||
45b4233c | 3832 | pr_debug("--- raid5d inactive\n"); |
1da177e4 LT |
3833 | } |
3834 | ||
3f294f4f | 3835 | static ssize_t |
007583c9 | 3836 | raid5_show_stripe_cache_size(mddev_t *mddev, char *page) |
3f294f4f | 3837 | { |
007583c9 | 3838 | raid5_conf_t *conf = mddev_to_conf(mddev); |
96de1e66 N |
3839 | if (conf) |
3840 | return sprintf(page, "%d\n", conf->max_nr_stripes); | |
3841 | else | |
3842 | return 0; | |
3f294f4f N |
3843 | } |
3844 | ||
3845 | static ssize_t | |
007583c9 | 3846 | raid5_store_stripe_cache_size(mddev_t *mddev, const char *page, size_t len) |
3f294f4f | 3847 | { |
007583c9 | 3848 | raid5_conf_t *conf = mddev_to_conf(mddev); |
4ef197d8 | 3849 | unsigned long new; |
b5470dc5 DW |
3850 | int err; |
3851 | ||
3f294f4f N |
3852 | if (len >= PAGE_SIZE) |
3853 | return -EINVAL; | |
96de1e66 N |
3854 | if (!conf) |
3855 | return -ENODEV; | |
3f294f4f | 3856 | |
4ef197d8 | 3857 | if (strict_strtoul(page, 10, &new)) |
3f294f4f N |
3858 | return -EINVAL; |
3859 | if (new <= 16 || new > 32768) | |
3860 | return -EINVAL; | |
3861 | while (new < conf->max_nr_stripes) { | |
3862 | if (drop_one_stripe(conf)) | |
3863 | conf->max_nr_stripes--; | |
3864 | else | |
3865 | break; | |
3866 | } | |
b5470dc5 DW |
3867 | err = md_allow_write(mddev); |
3868 | if (err) | |
3869 | return err; | |
3f294f4f N |
3870 | while (new > conf->max_nr_stripes) { |
3871 | if (grow_one_stripe(conf)) | |
3872 | conf->max_nr_stripes++; | |
3873 | else break; | |
3874 | } | |
3875 | return len; | |
3876 | } | |
007583c9 | 3877 | |
96de1e66 N |
3878 | static struct md_sysfs_entry |
3879 | raid5_stripecache_size = __ATTR(stripe_cache_size, S_IRUGO | S_IWUSR, | |
3880 | raid5_show_stripe_cache_size, | |
3881 | raid5_store_stripe_cache_size); | |
3f294f4f | 3882 | |
8b3e6cdc DW |
3883 | static ssize_t |
3884 | raid5_show_preread_threshold(mddev_t *mddev, char *page) | |
3885 | { | |
3886 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
3887 | if (conf) | |
3888 | return sprintf(page, "%d\n", conf->bypass_threshold); | |
3889 | else | |
3890 | return 0; | |
3891 | } | |
3892 | ||
3893 | static ssize_t | |
3894 | raid5_store_preread_threshold(mddev_t *mddev, const char *page, size_t len) | |
3895 | { | |
3896 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4ef197d8 | 3897 | unsigned long new; |
8b3e6cdc DW |
3898 | if (len >= PAGE_SIZE) |
3899 | return -EINVAL; | |
3900 | if (!conf) | |
3901 | return -ENODEV; | |
3902 | ||
4ef197d8 | 3903 | if (strict_strtoul(page, 10, &new)) |
8b3e6cdc | 3904 | return -EINVAL; |
4ef197d8 | 3905 | if (new > conf->max_nr_stripes) |
8b3e6cdc DW |
3906 | return -EINVAL; |
3907 | conf->bypass_threshold = new; | |
3908 | return len; | |
3909 | } | |
3910 | ||
3911 | static struct md_sysfs_entry | |
3912 | raid5_preread_bypass_threshold = __ATTR(preread_bypass_threshold, | |
3913 | S_IRUGO | S_IWUSR, | |
3914 | raid5_show_preread_threshold, | |
3915 | raid5_store_preread_threshold); | |
3916 | ||
3f294f4f | 3917 | static ssize_t |
96de1e66 | 3918 | stripe_cache_active_show(mddev_t *mddev, char *page) |
3f294f4f | 3919 | { |
007583c9 | 3920 | raid5_conf_t *conf = mddev_to_conf(mddev); |
96de1e66 N |
3921 | if (conf) |
3922 | return sprintf(page, "%d\n", atomic_read(&conf->active_stripes)); | |
3923 | else | |
3924 | return 0; | |
3f294f4f N |
3925 | } |
3926 | ||
96de1e66 N |
3927 | static struct md_sysfs_entry |
3928 | raid5_stripecache_active = __ATTR_RO(stripe_cache_active); | |
3f294f4f | 3929 | |
007583c9 | 3930 | static struct attribute *raid5_attrs[] = { |
3f294f4f N |
3931 | &raid5_stripecache_size.attr, |
3932 | &raid5_stripecache_active.attr, | |
8b3e6cdc | 3933 | &raid5_preread_bypass_threshold.attr, |
3f294f4f N |
3934 | NULL, |
3935 | }; | |
007583c9 N |
3936 | static struct attribute_group raid5_attrs_group = { |
3937 | .name = NULL, | |
3938 | .attrs = raid5_attrs, | |
3f294f4f N |
3939 | }; |
3940 | ||
72626685 | 3941 | static int run(mddev_t *mddev) |
1da177e4 LT |
3942 | { |
3943 | raid5_conf_t *conf; | |
3944 | int raid_disk, memory; | |
3945 | mdk_rdev_t *rdev; | |
3946 | struct disk_info *disk; | |
3947 | struct list_head *tmp; | |
02c2de8c | 3948 | int working_disks = 0; |
1da177e4 | 3949 | |
16a53ecc N |
3950 | if (mddev->level != 5 && mddev->level != 4 && mddev->level != 6) { |
3951 | printk(KERN_ERR "raid5: %s: raid level not set to 4/5/6 (%d)\n", | |
14f8d26b | 3952 | mdname(mddev), mddev->level); |
1da177e4 LT |
3953 | return -EIO; |
3954 | } | |
3955 | ||
f6705578 N |
3956 | if (mddev->reshape_position != MaxSector) { |
3957 | /* Check that we can continue the reshape. | |
3958 | * Currently only disks can change, it must | |
3959 | * increase, and we must be past the point where | |
3960 | * a stripe over-writes itself | |
3961 | */ | |
3962 | sector_t here_new, here_old; | |
3963 | int old_disks; | |
f416885e | 3964 | int max_degraded = (mddev->level == 5 ? 1 : 2); |
f6705578 N |
3965 | |
3966 | if (mddev->new_level != mddev->level || | |
3967 | mddev->new_layout != mddev->layout || | |
3968 | mddev->new_chunk != mddev->chunk_size) { | |
f416885e N |
3969 | printk(KERN_ERR "raid5: %s: unsupported reshape " |
3970 | "required - aborting.\n", | |
f6705578 N |
3971 | mdname(mddev)); |
3972 | return -EINVAL; | |
3973 | } | |
3974 | if (mddev->delta_disks <= 0) { | |
f416885e N |
3975 | printk(KERN_ERR "raid5: %s: unsupported reshape " |
3976 | "(reduce disks) required - aborting.\n", | |
f6705578 N |
3977 | mdname(mddev)); |
3978 | return -EINVAL; | |
3979 | } | |
3980 | old_disks = mddev->raid_disks - mddev->delta_disks; | |
3981 | /* reshape_position must be on a new-stripe boundary, and one | |
f416885e N |
3982 | * further up in new geometry must map after here in old |
3983 | * geometry. | |
f6705578 N |
3984 | */ |
3985 | here_new = mddev->reshape_position; | |
f416885e N |
3986 | if (sector_div(here_new, (mddev->chunk_size>>9)* |
3987 | (mddev->raid_disks - max_degraded))) { | |
3988 | printk(KERN_ERR "raid5: reshape_position not " | |
3989 | "on a stripe boundary\n"); | |
f6705578 N |
3990 | return -EINVAL; |
3991 | } | |
3992 | /* here_new is the stripe we will write to */ | |
3993 | here_old = mddev->reshape_position; | |
f416885e N |
3994 | sector_div(here_old, (mddev->chunk_size>>9)* |
3995 | (old_disks-max_degraded)); | |
3996 | /* here_old is the first stripe that we might need to read | |
3997 | * from */ | |
f6705578 N |
3998 | if (here_new >= here_old) { |
3999 | /* Reading from the same stripe as writing to - bad */ | |
f416885e N |
4000 | printk(KERN_ERR "raid5: reshape_position too early for " |
4001 | "auto-recovery - aborting.\n"); | |
f6705578 N |
4002 | return -EINVAL; |
4003 | } | |
4004 | printk(KERN_INFO "raid5: reshape will continue\n"); | |
4005 | /* OK, we should be able to continue; */ | |
4006 | } | |
4007 | ||
4008 | ||
b55e6bfc | 4009 | mddev->private = kzalloc(sizeof (raid5_conf_t), GFP_KERNEL); |
1da177e4 LT |
4010 | if ((conf = mddev->private) == NULL) |
4011 | goto abort; | |
f6705578 N |
4012 | if (mddev->reshape_position == MaxSector) { |
4013 | conf->previous_raid_disks = conf->raid_disks = mddev->raid_disks; | |
4014 | } else { | |
4015 | conf->raid_disks = mddev->raid_disks; | |
4016 | conf->previous_raid_disks = mddev->raid_disks - mddev->delta_disks; | |
4017 | } | |
4018 | ||
4019 | conf->disks = kzalloc(conf->raid_disks * sizeof(struct disk_info), | |
b55e6bfc N |
4020 | GFP_KERNEL); |
4021 | if (!conf->disks) | |
4022 | goto abort; | |
9ffae0cf | 4023 | |
1da177e4 LT |
4024 | conf->mddev = mddev; |
4025 | ||
fccddba0 | 4026 | if ((conf->stripe_hashtbl = kzalloc(PAGE_SIZE, GFP_KERNEL)) == NULL) |
1da177e4 | 4027 | goto abort; |
1da177e4 | 4028 | |
16a53ecc N |
4029 | if (mddev->level == 6) { |
4030 | conf->spare_page = alloc_page(GFP_KERNEL); | |
4031 | if (!conf->spare_page) | |
4032 | goto abort; | |
4033 | } | |
1da177e4 | 4034 | spin_lock_init(&conf->device_lock); |
e7e72bf6 | 4035 | mddev->queue->queue_lock = &conf->device_lock; |
1da177e4 LT |
4036 | init_waitqueue_head(&conf->wait_for_stripe); |
4037 | init_waitqueue_head(&conf->wait_for_overlap); | |
4038 | INIT_LIST_HEAD(&conf->handle_list); | |
8b3e6cdc | 4039 | INIT_LIST_HEAD(&conf->hold_list); |
1da177e4 | 4040 | INIT_LIST_HEAD(&conf->delayed_list); |
72626685 | 4041 | INIT_LIST_HEAD(&conf->bitmap_list); |
1da177e4 LT |
4042 | INIT_LIST_HEAD(&conf->inactive_list); |
4043 | atomic_set(&conf->active_stripes, 0); | |
4044 | atomic_set(&conf->preread_active_stripes, 0); | |
46031f9a | 4045 | atomic_set(&conf->active_aligned_reads, 0); |
8b3e6cdc | 4046 | conf->bypass_threshold = BYPASS_THRESHOLD; |
1da177e4 | 4047 | |
45b4233c | 4048 | pr_debug("raid5: run(%s) called.\n", mdname(mddev)); |
1da177e4 | 4049 | |
d089c6af | 4050 | rdev_for_each(rdev, tmp, mddev) { |
1da177e4 | 4051 | raid_disk = rdev->raid_disk; |
f6705578 | 4052 | if (raid_disk >= conf->raid_disks |
1da177e4 LT |
4053 | || raid_disk < 0) |
4054 | continue; | |
4055 | disk = conf->disks + raid_disk; | |
4056 | ||
4057 | disk->rdev = rdev; | |
4058 | ||
b2d444d7 | 4059 | if (test_bit(In_sync, &rdev->flags)) { |
1da177e4 LT |
4060 | char b[BDEVNAME_SIZE]; |
4061 | printk(KERN_INFO "raid5: device %s operational as raid" | |
4062 | " disk %d\n", bdevname(rdev->bdev,b), | |
4063 | raid_disk); | |
02c2de8c | 4064 | working_disks++; |
8c2e870a NB |
4065 | } else |
4066 | /* Cannot rely on bitmap to complete recovery */ | |
4067 | conf->fullsync = 1; | |
1da177e4 LT |
4068 | } |
4069 | ||
1da177e4 | 4070 | /* |
16a53ecc | 4071 | * 0 for a fully functional array, 1 or 2 for a degraded array. |
1da177e4 | 4072 | */ |
02c2de8c | 4073 | mddev->degraded = conf->raid_disks - working_disks; |
1da177e4 LT |
4074 | conf->mddev = mddev; |
4075 | conf->chunk_size = mddev->chunk_size; | |
4076 | conf->level = mddev->level; | |
16a53ecc N |
4077 | if (conf->level == 6) |
4078 | conf->max_degraded = 2; | |
4079 | else | |
4080 | conf->max_degraded = 1; | |
1da177e4 LT |
4081 | conf->algorithm = mddev->layout; |
4082 | conf->max_nr_stripes = NR_STRIPES; | |
f6705578 | 4083 | conf->expand_progress = mddev->reshape_position; |
1da177e4 LT |
4084 | |
4085 | /* device size must be a multiple of chunk size */ | |
4086 | mddev->size &= ~(mddev->chunk_size/1024 -1); | |
b1581566 | 4087 | mddev->resync_max_sectors = mddev->size << 1; |
1da177e4 | 4088 | |
16a53ecc N |
4089 | if (conf->level == 6 && conf->raid_disks < 4) { |
4090 | printk(KERN_ERR "raid6: not enough configured devices for %s (%d, minimum 4)\n", | |
4091 | mdname(mddev), conf->raid_disks); | |
4092 | goto abort; | |
4093 | } | |
1da177e4 LT |
4094 | if (!conf->chunk_size || conf->chunk_size % 4) { |
4095 | printk(KERN_ERR "raid5: invalid chunk size %d for %s\n", | |
4096 | conf->chunk_size, mdname(mddev)); | |
4097 | goto abort; | |
4098 | } | |
4099 | if (conf->algorithm > ALGORITHM_RIGHT_SYMMETRIC) { | |
4100 | printk(KERN_ERR | |
4101 | "raid5: unsupported parity algorithm %d for %s\n", | |
4102 | conf->algorithm, mdname(mddev)); | |
4103 | goto abort; | |
4104 | } | |
16a53ecc | 4105 | if (mddev->degraded > conf->max_degraded) { |
1da177e4 LT |
4106 | printk(KERN_ERR "raid5: not enough operational devices for %s" |
4107 | " (%d/%d failed)\n", | |
02c2de8c | 4108 | mdname(mddev), mddev->degraded, conf->raid_disks); |
1da177e4 LT |
4109 | goto abort; |
4110 | } | |
4111 | ||
16a53ecc | 4112 | if (mddev->degraded > 0 && |
1da177e4 | 4113 | mddev->recovery_cp != MaxSector) { |
6ff8d8ec N |
4114 | if (mddev->ok_start_degraded) |
4115 | printk(KERN_WARNING | |
4116 | "raid5: starting dirty degraded array: %s" | |
4117 | "- data corruption possible.\n", | |
4118 | mdname(mddev)); | |
4119 | else { | |
4120 | printk(KERN_ERR | |
4121 | "raid5: cannot start dirty degraded array for %s\n", | |
4122 | mdname(mddev)); | |
4123 | goto abort; | |
4124 | } | |
1da177e4 LT |
4125 | } |
4126 | ||
4127 | { | |
4128 | mddev->thread = md_register_thread(raid5d, mddev, "%s_raid5"); | |
4129 | if (!mddev->thread) { | |
4130 | printk(KERN_ERR | |
4131 | "raid5: couldn't allocate thread for %s\n", | |
4132 | mdname(mddev)); | |
4133 | goto abort; | |
4134 | } | |
4135 | } | |
5036805b | 4136 | memory = conf->max_nr_stripes * (sizeof(struct stripe_head) + |
1da177e4 LT |
4137 | conf->raid_disks * ((sizeof(struct bio) + PAGE_SIZE))) / 1024; |
4138 | if (grow_stripes(conf, conf->max_nr_stripes)) { | |
4139 | printk(KERN_ERR | |
4140 | "raid5: couldn't allocate %dkB for buffers\n", memory); | |
4141 | shrink_stripes(conf); | |
4142 | md_unregister_thread(mddev->thread); | |
4143 | goto abort; | |
4144 | } else | |
4145 | printk(KERN_INFO "raid5: allocated %dkB for %s\n", | |
4146 | memory, mdname(mddev)); | |
4147 | ||
4148 | if (mddev->degraded == 0) | |
4149 | printk("raid5: raid level %d set %s active with %d out of %d" | |
4150 | " devices, algorithm %d\n", conf->level, mdname(mddev), | |
4151 | mddev->raid_disks-mddev->degraded, mddev->raid_disks, | |
4152 | conf->algorithm); | |
4153 | else | |
4154 | printk(KERN_ALERT "raid5: raid level %d set %s active with %d" | |
4155 | " out of %d devices, algorithm %d\n", conf->level, | |
4156 | mdname(mddev), mddev->raid_disks - mddev->degraded, | |
4157 | mddev->raid_disks, conf->algorithm); | |
4158 | ||
4159 | print_raid5_conf(conf); | |
4160 | ||
f6705578 N |
4161 | if (conf->expand_progress != MaxSector) { |
4162 | printk("...ok start reshape thread\n"); | |
b578d55f | 4163 | conf->expand_lo = conf->expand_progress; |
f6705578 N |
4164 | atomic_set(&conf->reshape_stripes, 0); |
4165 | clear_bit(MD_RECOVERY_SYNC, &mddev->recovery); | |
4166 | clear_bit(MD_RECOVERY_CHECK, &mddev->recovery); | |
4167 | set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery); | |
4168 | set_bit(MD_RECOVERY_RUNNING, &mddev->recovery); | |
4169 | mddev->sync_thread = md_register_thread(md_do_sync, mddev, | |
4170 | "%s_reshape"); | |
f6705578 N |
4171 | } |
4172 | ||
1da177e4 | 4173 | /* read-ahead size must cover two whole stripes, which is |
16a53ecc | 4174 | * 2 * (datadisks) * chunksize where 'n' is the number of raid devices |
1da177e4 LT |
4175 | */ |
4176 | { | |
16a53ecc N |
4177 | int data_disks = conf->previous_raid_disks - conf->max_degraded; |
4178 | int stripe = data_disks * | |
8932c2e0 | 4179 | (mddev->chunk_size / PAGE_SIZE); |
1da177e4 LT |
4180 | if (mddev->queue->backing_dev_info.ra_pages < 2 * stripe) |
4181 | mddev->queue->backing_dev_info.ra_pages = 2 * stripe; | |
4182 | } | |
4183 | ||
4184 | /* Ok, everything is just fine now */ | |
5e55e2f5 N |
4185 | if (sysfs_create_group(&mddev->kobj, &raid5_attrs_group)) |
4186 | printk(KERN_WARNING | |
4187 | "raid5: failed to create sysfs attributes for %s\n", | |
4188 | mdname(mddev)); | |
7a5febe9 N |
4189 | |
4190 | mddev->queue->unplug_fn = raid5_unplug_device; | |
f022b2fd | 4191 | mddev->queue->backing_dev_info.congested_data = mddev; |
041ae52e | 4192 | mddev->queue->backing_dev_info.congested_fn = raid5_congested; |
f022b2fd | 4193 | |
f233ea5c | 4194 | mddev->array_sectors = 2 * mddev->size * (conf->previous_raid_disks - |
16a53ecc | 4195 | conf->max_degraded); |
7a5febe9 | 4196 | |
23032a0e RBJ |
4197 | blk_queue_merge_bvec(mddev->queue, raid5_mergeable_bvec); |
4198 | ||
1da177e4 LT |
4199 | return 0; |
4200 | abort: | |
4201 | if (conf) { | |
4202 | print_raid5_conf(conf); | |
16a53ecc | 4203 | safe_put_page(conf->spare_page); |
b55e6bfc | 4204 | kfree(conf->disks); |
fccddba0 | 4205 | kfree(conf->stripe_hashtbl); |
1da177e4 LT |
4206 | kfree(conf); |
4207 | } | |
4208 | mddev->private = NULL; | |
4209 | printk(KERN_ALERT "raid5: failed to run raid set %s\n", mdname(mddev)); | |
4210 | return -EIO; | |
4211 | } | |
4212 | ||
4213 | ||
4214 | ||
3f294f4f | 4215 | static int stop(mddev_t *mddev) |
1da177e4 LT |
4216 | { |
4217 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; | |
4218 | ||
4219 | md_unregister_thread(mddev->thread); | |
4220 | mddev->thread = NULL; | |
4221 | shrink_stripes(conf); | |
fccddba0 | 4222 | kfree(conf->stripe_hashtbl); |
041ae52e | 4223 | mddev->queue->backing_dev_info.congested_fn = NULL; |
1da177e4 | 4224 | blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/ |
007583c9 | 4225 | sysfs_remove_group(&mddev->kobj, &raid5_attrs_group); |
b55e6bfc | 4226 | kfree(conf->disks); |
96de1e66 | 4227 | kfree(conf); |
1da177e4 LT |
4228 | mddev->private = NULL; |
4229 | return 0; | |
4230 | } | |
4231 | ||
45b4233c | 4232 | #ifdef DEBUG |
16a53ecc | 4233 | static void print_sh (struct seq_file *seq, struct stripe_head *sh) |
1da177e4 LT |
4234 | { |
4235 | int i; | |
4236 | ||
16a53ecc N |
4237 | seq_printf(seq, "sh %llu, pd_idx %d, state %ld.\n", |
4238 | (unsigned long long)sh->sector, sh->pd_idx, sh->state); | |
4239 | seq_printf(seq, "sh %llu, count %d.\n", | |
4240 | (unsigned long long)sh->sector, atomic_read(&sh->count)); | |
4241 | seq_printf(seq, "sh %llu, ", (unsigned long long)sh->sector); | |
7ecaa1e6 | 4242 | for (i = 0; i < sh->disks; i++) { |
16a53ecc N |
4243 | seq_printf(seq, "(cache%d: %p %ld) ", |
4244 | i, sh->dev[i].page, sh->dev[i].flags); | |
1da177e4 | 4245 | } |
16a53ecc | 4246 | seq_printf(seq, "\n"); |
1da177e4 LT |
4247 | } |
4248 | ||
16a53ecc | 4249 | static void printall (struct seq_file *seq, raid5_conf_t *conf) |
1da177e4 LT |
4250 | { |
4251 | struct stripe_head *sh; | |
fccddba0 | 4252 | struct hlist_node *hn; |
1da177e4 LT |
4253 | int i; |
4254 | ||
4255 | spin_lock_irq(&conf->device_lock); | |
4256 | for (i = 0; i < NR_HASH; i++) { | |
fccddba0 | 4257 | hlist_for_each_entry(sh, hn, &conf->stripe_hashtbl[i], hash) { |
1da177e4 LT |
4258 | if (sh->raid_conf != conf) |
4259 | continue; | |
16a53ecc | 4260 | print_sh(seq, sh); |
1da177e4 LT |
4261 | } |
4262 | } | |
4263 | spin_unlock_irq(&conf->device_lock); | |
4264 | } | |
4265 | #endif | |
4266 | ||
4267 | static void status (struct seq_file *seq, mddev_t *mddev) | |
4268 | { | |
4269 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; | |
4270 | int i; | |
4271 | ||
4272 | seq_printf (seq, " level %d, %dk chunk, algorithm %d", mddev->level, mddev->chunk_size >> 10, mddev->layout); | |
02c2de8c | 4273 | seq_printf (seq, " [%d/%d] [", conf->raid_disks, conf->raid_disks - mddev->degraded); |
1da177e4 LT |
4274 | for (i = 0; i < conf->raid_disks; i++) |
4275 | seq_printf (seq, "%s", | |
4276 | conf->disks[i].rdev && | |
b2d444d7 | 4277 | test_bit(In_sync, &conf->disks[i].rdev->flags) ? "U" : "_"); |
1da177e4 | 4278 | seq_printf (seq, "]"); |
45b4233c | 4279 | #ifdef DEBUG |
16a53ecc N |
4280 | seq_printf (seq, "\n"); |
4281 | printall(seq, conf); | |
1da177e4 LT |
4282 | #endif |
4283 | } | |
4284 | ||
4285 | static void print_raid5_conf (raid5_conf_t *conf) | |
4286 | { | |
4287 | int i; | |
4288 | struct disk_info *tmp; | |
4289 | ||
4290 | printk("RAID5 conf printout:\n"); | |
4291 | if (!conf) { | |
4292 | printk("(conf==NULL)\n"); | |
4293 | return; | |
4294 | } | |
02c2de8c N |
4295 | printk(" --- rd:%d wd:%d\n", conf->raid_disks, |
4296 | conf->raid_disks - conf->mddev->degraded); | |
1da177e4 LT |
4297 | |
4298 | for (i = 0; i < conf->raid_disks; i++) { | |
4299 | char b[BDEVNAME_SIZE]; | |
4300 | tmp = conf->disks + i; | |
4301 | if (tmp->rdev) | |
4302 | printk(" disk %d, o:%d, dev:%s\n", | |
b2d444d7 | 4303 | i, !test_bit(Faulty, &tmp->rdev->flags), |
1da177e4 LT |
4304 | bdevname(tmp->rdev->bdev,b)); |
4305 | } | |
4306 | } | |
4307 | ||
4308 | static int raid5_spare_active(mddev_t *mddev) | |
4309 | { | |
4310 | int i; | |
4311 | raid5_conf_t *conf = mddev->private; | |
4312 | struct disk_info *tmp; | |
4313 | ||
4314 | for (i = 0; i < conf->raid_disks; i++) { | |
4315 | tmp = conf->disks + i; | |
4316 | if (tmp->rdev | |
b2d444d7 | 4317 | && !test_bit(Faulty, &tmp->rdev->flags) |
c04be0aa N |
4318 | && !test_and_set_bit(In_sync, &tmp->rdev->flags)) { |
4319 | unsigned long flags; | |
4320 | spin_lock_irqsave(&conf->device_lock, flags); | |
1da177e4 | 4321 | mddev->degraded--; |
c04be0aa | 4322 | spin_unlock_irqrestore(&conf->device_lock, flags); |
1da177e4 LT |
4323 | } |
4324 | } | |
4325 | print_raid5_conf(conf); | |
4326 | return 0; | |
4327 | } | |
4328 | ||
4329 | static int raid5_remove_disk(mddev_t *mddev, int number) | |
4330 | { | |
4331 | raid5_conf_t *conf = mddev->private; | |
4332 | int err = 0; | |
4333 | mdk_rdev_t *rdev; | |
4334 | struct disk_info *p = conf->disks + number; | |
4335 | ||
4336 | print_raid5_conf(conf); | |
4337 | rdev = p->rdev; | |
4338 | if (rdev) { | |
b2d444d7 | 4339 | if (test_bit(In_sync, &rdev->flags) || |
1da177e4 LT |
4340 | atomic_read(&rdev->nr_pending)) { |
4341 | err = -EBUSY; | |
4342 | goto abort; | |
4343 | } | |
dfc70645 N |
4344 | /* Only remove non-faulty devices if recovery |
4345 | * isn't possible. | |
4346 | */ | |
4347 | if (!test_bit(Faulty, &rdev->flags) && | |
4348 | mddev->degraded <= conf->max_degraded) { | |
4349 | err = -EBUSY; | |
4350 | goto abort; | |
4351 | } | |
1da177e4 | 4352 | p->rdev = NULL; |
fbd568a3 | 4353 | synchronize_rcu(); |
1da177e4 LT |
4354 | if (atomic_read(&rdev->nr_pending)) { |
4355 | /* lost the race, try later */ | |
4356 | err = -EBUSY; | |
4357 | p->rdev = rdev; | |
4358 | } | |
4359 | } | |
4360 | abort: | |
4361 | ||
4362 | print_raid5_conf(conf); | |
4363 | return err; | |
4364 | } | |
4365 | ||
4366 | static int raid5_add_disk(mddev_t *mddev, mdk_rdev_t *rdev) | |
4367 | { | |
4368 | raid5_conf_t *conf = mddev->private; | |
199050ea | 4369 | int err = -EEXIST; |
1da177e4 LT |
4370 | int disk; |
4371 | struct disk_info *p; | |
6c2fce2e NB |
4372 | int first = 0; |
4373 | int last = conf->raid_disks - 1; | |
1da177e4 | 4374 | |
16a53ecc | 4375 | if (mddev->degraded > conf->max_degraded) |
1da177e4 | 4376 | /* no point adding a device */ |
199050ea | 4377 | return -EINVAL; |
1da177e4 | 4378 | |
6c2fce2e NB |
4379 | if (rdev->raid_disk >= 0) |
4380 | first = last = rdev->raid_disk; | |
1da177e4 LT |
4381 | |
4382 | /* | |
16a53ecc N |
4383 | * find the disk ... but prefer rdev->saved_raid_disk |
4384 | * if possible. | |
1da177e4 | 4385 | */ |
16a53ecc | 4386 | if (rdev->saved_raid_disk >= 0 && |
6c2fce2e | 4387 | rdev->saved_raid_disk >= first && |
16a53ecc N |
4388 | conf->disks[rdev->saved_raid_disk].rdev == NULL) |
4389 | disk = rdev->saved_raid_disk; | |
4390 | else | |
6c2fce2e NB |
4391 | disk = first; |
4392 | for ( ; disk <= last ; disk++) | |
1da177e4 | 4393 | if ((p=conf->disks + disk)->rdev == NULL) { |
b2d444d7 | 4394 | clear_bit(In_sync, &rdev->flags); |
1da177e4 | 4395 | rdev->raid_disk = disk; |
199050ea | 4396 | err = 0; |
72626685 N |
4397 | if (rdev->saved_raid_disk != disk) |
4398 | conf->fullsync = 1; | |
d6065f7b | 4399 | rcu_assign_pointer(p->rdev, rdev); |
1da177e4 LT |
4400 | break; |
4401 | } | |
4402 | print_raid5_conf(conf); | |
199050ea | 4403 | return err; |
1da177e4 LT |
4404 | } |
4405 | ||
4406 | static int raid5_resize(mddev_t *mddev, sector_t sectors) | |
4407 | { | |
4408 | /* no resync is happening, and there is enough space | |
4409 | * on all devices, so we can resize. | |
4410 | * We need to make sure resync covers any new space. | |
4411 | * If the array is shrinking we should possibly wait until | |
4412 | * any io in the removed space completes, but it hardly seems | |
4413 | * worth it. | |
4414 | */ | |
16a53ecc N |
4415 | raid5_conf_t *conf = mddev_to_conf(mddev); |
4416 | ||
1da177e4 | 4417 | sectors &= ~((sector_t)mddev->chunk_size/512 - 1); |
f233ea5c AN |
4418 | mddev->array_sectors = sectors * (mddev->raid_disks |
4419 | - conf->max_degraded); | |
4420 | set_capacity(mddev->gendisk, mddev->array_sectors); | |
44ce6294 | 4421 | mddev->changed = 1; |
1da177e4 LT |
4422 | if (sectors/2 > mddev->size && mddev->recovery_cp == MaxSector) { |
4423 | mddev->recovery_cp = mddev->size << 1; | |
4424 | set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); | |
4425 | } | |
4426 | mddev->size = sectors /2; | |
4b5c7ae8 | 4427 | mddev->resync_max_sectors = sectors; |
1da177e4 LT |
4428 | return 0; |
4429 | } | |
4430 | ||
29269553 | 4431 | #ifdef CONFIG_MD_RAID5_RESHAPE |
63c70c4f | 4432 | static int raid5_check_reshape(mddev_t *mddev) |
29269553 N |
4433 | { |
4434 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4435 | int err; | |
29269553 | 4436 | |
63c70c4f N |
4437 | if (mddev->delta_disks < 0 || |
4438 | mddev->new_level != mddev->level) | |
4439 | return -EINVAL; /* Cannot shrink array or change level yet */ | |
4440 | if (mddev->delta_disks == 0) | |
29269553 N |
4441 | return 0; /* nothing to do */ |
4442 | ||
4443 | /* Can only proceed if there are plenty of stripe_heads. | |
4444 | * We need a minimum of one full stripe,, and for sensible progress | |
4445 | * it is best to have about 4 times that. | |
4446 | * If we require 4 times, then the default 256 4K stripe_heads will | |
4447 | * allow for chunk sizes up to 256K, which is probably OK. | |
4448 | * If the chunk size is greater, user-space should request more | |
4449 | * stripe_heads first. | |
4450 | */ | |
63c70c4f N |
4451 | if ((mddev->chunk_size / STRIPE_SIZE) * 4 > conf->max_nr_stripes || |
4452 | (mddev->new_chunk / STRIPE_SIZE) * 4 > conf->max_nr_stripes) { | |
29269553 N |
4453 | printk(KERN_WARNING "raid5: reshape: not enough stripes. Needed %lu\n", |
4454 | (mddev->chunk_size / STRIPE_SIZE)*4); | |
4455 | return -ENOSPC; | |
4456 | } | |
4457 | ||
63c70c4f N |
4458 | err = resize_stripes(conf, conf->raid_disks + mddev->delta_disks); |
4459 | if (err) | |
4460 | return err; | |
4461 | ||
b4c4c7b8 N |
4462 | if (mddev->degraded > conf->max_degraded) |
4463 | return -EINVAL; | |
63c70c4f N |
4464 | /* looks like we might be able to manage this */ |
4465 | return 0; | |
4466 | } | |
4467 | ||
4468 | static int raid5_start_reshape(mddev_t *mddev) | |
4469 | { | |
4470 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4471 | mdk_rdev_t *rdev; | |
4472 | struct list_head *rtmp; | |
4473 | int spares = 0; | |
4474 | int added_devices = 0; | |
c04be0aa | 4475 | unsigned long flags; |
63c70c4f | 4476 | |
f416885e | 4477 | if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) |
63c70c4f N |
4478 | return -EBUSY; |
4479 | ||
d089c6af | 4480 | rdev_for_each(rdev, rtmp, mddev) |
29269553 N |
4481 | if (rdev->raid_disk < 0 && |
4482 | !test_bit(Faulty, &rdev->flags)) | |
4483 | spares++; | |
63c70c4f | 4484 | |
f416885e | 4485 | if (spares - mddev->degraded < mddev->delta_disks - conf->max_degraded) |
29269553 N |
4486 | /* Not enough devices even to make a degraded array |
4487 | * of that size | |
4488 | */ | |
4489 | return -EINVAL; | |
4490 | ||
f6705578 | 4491 | atomic_set(&conf->reshape_stripes, 0); |
29269553 N |
4492 | spin_lock_irq(&conf->device_lock); |
4493 | conf->previous_raid_disks = conf->raid_disks; | |
63c70c4f | 4494 | conf->raid_disks += mddev->delta_disks; |
29269553 | 4495 | conf->expand_progress = 0; |
b578d55f | 4496 | conf->expand_lo = 0; |
29269553 N |
4497 | spin_unlock_irq(&conf->device_lock); |
4498 | ||
4499 | /* Add some new drives, as many as will fit. | |
4500 | * We know there are enough to make the newly sized array work. | |
4501 | */ | |
d089c6af | 4502 | rdev_for_each(rdev, rtmp, mddev) |
29269553 N |
4503 | if (rdev->raid_disk < 0 && |
4504 | !test_bit(Faulty, &rdev->flags)) { | |
199050ea | 4505 | if (raid5_add_disk(mddev, rdev) == 0) { |
29269553 N |
4506 | char nm[20]; |
4507 | set_bit(In_sync, &rdev->flags); | |
29269553 | 4508 | added_devices++; |
5fd6c1dc | 4509 | rdev->recovery_offset = 0; |
29269553 | 4510 | sprintf(nm, "rd%d", rdev->raid_disk); |
5e55e2f5 N |
4511 | if (sysfs_create_link(&mddev->kobj, |
4512 | &rdev->kobj, nm)) | |
4513 | printk(KERN_WARNING | |
4514 | "raid5: failed to create " | |
4515 | " link %s for %s\n", | |
4516 | nm, mdname(mddev)); | |
29269553 N |
4517 | } else |
4518 | break; | |
4519 | } | |
4520 | ||
c04be0aa | 4521 | spin_lock_irqsave(&conf->device_lock, flags); |
63c70c4f | 4522 | mddev->degraded = (conf->raid_disks - conf->previous_raid_disks) - added_devices; |
c04be0aa | 4523 | spin_unlock_irqrestore(&conf->device_lock, flags); |
63c70c4f | 4524 | mddev->raid_disks = conf->raid_disks; |
f6705578 | 4525 | mddev->reshape_position = 0; |
850b2b42 | 4526 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
f6705578 | 4527 | |
29269553 N |
4528 | clear_bit(MD_RECOVERY_SYNC, &mddev->recovery); |
4529 | clear_bit(MD_RECOVERY_CHECK, &mddev->recovery); | |
4530 | set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery); | |
4531 | set_bit(MD_RECOVERY_RUNNING, &mddev->recovery); | |
4532 | mddev->sync_thread = md_register_thread(md_do_sync, mddev, | |
4533 | "%s_reshape"); | |
4534 | if (!mddev->sync_thread) { | |
4535 | mddev->recovery = 0; | |
4536 | spin_lock_irq(&conf->device_lock); | |
4537 | mddev->raid_disks = conf->raid_disks = conf->previous_raid_disks; | |
4538 | conf->expand_progress = MaxSector; | |
4539 | spin_unlock_irq(&conf->device_lock); | |
4540 | return -EAGAIN; | |
4541 | } | |
4542 | md_wakeup_thread(mddev->sync_thread); | |
4543 | md_new_event(mddev); | |
4544 | return 0; | |
4545 | } | |
4546 | #endif | |
4547 | ||
4548 | static void end_reshape(raid5_conf_t *conf) | |
4549 | { | |
4550 | struct block_device *bdev; | |
4551 | ||
f6705578 | 4552 | if (!test_bit(MD_RECOVERY_INTR, &conf->mddev->recovery)) { |
f233ea5c | 4553 | conf->mddev->array_sectors = 2 * conf->mddev->size * |
f416885e | 4554 | (conf->raid_disks - conf->max_degraded); |
f233ea5c | 4555 | set_capacity(conf->mddev->gendisk, conf->mddev->array_sectors); |
44ce6294 | 4556 | conf->mddev->changed = 1; |
f6705578 N |
4557 | |
4558 | bdev = bdget_disk(conf->mddev->gendisk, 0); | |
4559 | if (bdev) { | |
4560 | mutex_lock(&bdev->bd_inode->i_mutex); | |
f233ea5c AN |
4561 | i_size_write(bdev->bd_inode, |
4562 | (loff_t)conf->mddev->array_sectors << 9); | |
f6705578 N |
4563 | mutex_unlock(&bdev->bd_inode->i_mutex); |
4564 | bdput(bdev); | |
4565 | } | |
4566 | spin_lock_irq(&conf->device_lock); | |
4567 | conf->expand_progress = MaxSector; | |
4568 | spin_unlock_irq(&conf->device_lock); | |
4569 | conf->mddev->reshape_position = MaxSector; | |
16a53ecc N |
4570 | |
4571 | /* read-ahead size must cover two whole stripes, which is | |
4572 | * 2 * (datadisks) * chunksize where 'n' is the number of raid devices | |
4573 | */ | |
4574 | { | |
4575 | int data_disks = conf->previous_raid_disks - conf->max_degraded; | |
4576 | int stripe = data_disks * | |
4577 | (conf->mddev->chunk_size / PAGE_SIZE); | |
4578 | if (conf->mddev->queue->backing_dev_info.ra_pages < 2 * stripe) | |
4579 | conf->mddev->queue->backing_dev_info.ra_pages = 2 * stripe; | |
4580 | } | |
29269553 | 4581 | } |
29269553 N |
4582 | } |
4583 | ||
72626685 N |
4584 | static void raid5_quiesce(mddev_t *mddev, int state) |
4585 | { | |
4586 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4587 | ||
4588 | switch(state) { | |
e464eafd N |
4589 | case 2: /* resume for a suspend */ |
4590 | wake_up(&conf->wait_for_overlap); | |
4591 | break; | |
4592 | ||
72626685 N |
4593 | case 1: /* stop all writes */ |
4594 | spin_lock_irq(&conf->device_lock); | |
4595 | conf->quiesce = 1; | |
4596 | wait_event_lock_irq(conf->wait_for_stripe, | |
46031f9a RBJ |
4597 | atomic_read(&conf->active_stripes) == 0 && |
4598 | atomic_read(&conf->active_aligned_reads) == 0, | |
72626685 N |
4599 | conf->device_lock, /* nothing */); |
4600 | spin_unlock_irq(&conf->device_lock); | |
4601 | break; | |
4602 | ||
4603 | case 0: /* re-enable writes */ | |
4604 | spin_lock_irq(&conf->device_lock); | |
4605 | conf->quiesce = 0; | |
4606 | wake_up(&conf->wait_for_stripe); | |
e464eafd | 4607 | wake_up(&conf->wait_for_overlap); |
72626685 N |
4608 | spin_unlock_irq(&conf->device_lock); |
4609 | break; | |
4610 | } | |
72626685 | 4611 | } |
b15c2e57 | 4612 | |
16a53ecc N |
4613 | static struct mdk_personality raid6_personality = |
4614 | { | |
4615 | .name = "raid6", | |
4616 | .level = 6, | |
4617 | .owner = THIS_MODULE, | |
4618 | .make_request = make_request, | |
4619 | .run = run, | |
4620 | .stop = stop, | |
4621 | .status = status, | |
4622 | .error_handler = error, | |
4623 | .hot_add_disk = raid5_add_disk, | |
4624 | .hot_remove_disk= raid5_remove_disk, | |
4625 | .spare_active = raid5_spare_active, | |
4626 | .sync_request = sync_request, | |
4627 | .resize = raid5_resize, | |
f416885e N |
4628 | #ifdef CONFIG_MD_RAID5_RESHAPE |
4629 | .check_reshape = raid5_check_reshape, | |
4630 | .start_reshape = raid5_start_reshape, | |
4631 | #endif | |
16a53ecc N |
4632 | .quiesce = raid5_quiesce, |
4633 | }; | |
2604b703 | 4634 | static struct mdk_personality raid5_personality = |
1da177e4 LT |
4635 | { |
4636 | .name = "raid5", | |
2604b703 | 4637 | .level = 5, |
1da177e4 LT |
4638 | .owner = THIS_MODULE, |
4639 | .make_request = make_request, | |
4640 | .run = run, | |
4641 | .stop = stop, | |
4642 | .status = status, | |
4643 | .error_handler = error, | |
4644 | .hot_add_disk = raid5_add_disk, | |
4645 | .hot_remove_disk= raid5_remove_disk, | |
4646 | .spare_active = raid5_spare_active, | |
4647 | .sync_request = sync_request, | |
4648 | .resize = raid5_resize, | |
29269553 | 4649 | #ifdef CONFIG_MD_RAID5_RESHAPE |
63c70c4f N |
4650 | .check_reshape = raid5_check_reshape, |
4651 | .start_reshape = raid5_start_reshape, | |
29269553 | 4652 | #endif |
72626685 | 4653 | .quiesce = raid5_quiesce, |
1da177e4 LT |
4654 | }; |
4655 | ||
2604b703 | 4656 | static struct mdk_personality raid4_personality = |
1da177e4 | 4657 | { |
2604b703 N |
4658 | .name = "raid4", |
4659 | .level = 4, | |
4660 | .owner = THIS_MODULE, | |
4661 | .make_request = make_request, | |
4662 | .run = run, | |
4663 | .stop = stop, | |
4664 | .status = status, | |
4665 | .error_handler = error, | |
4666 | .hot_add_disk = raid5_add_disk, | |
4667 | .hot_remove_disk= raid5_remove_disk, | |
4668 | .spare_active = raid5_spare_active, | |
4669 | .sync_request = sync_request, | |
4670 | .resize = raid5_resize, | |
3d37890b N |
4671 | #ifdef CONFIG_MD_RAID5_RESHAPE |
4672 | .check_reshape = raid5_check_reshape, | |
4673 | .start_reshape = raid5_start_reshape, | |
4674 | #endif | |
2604b703 N |
4675 | .quiesce = raid5_quiesce, |
4676 | }; | |
4677 | ||
4678 | static int __init raid5_init(void) | |
4679 | { | |
16a53ecc N |
4680 | int e; |
4681 | ||
4682 | e = raid6_select_algo(); | |
4683 | if ( e ) | |
4684 | return e; | |
4685 | register_md_personality(&raid6_personality); | |
2604b703 N |
4686 | register_md_personality(&raid5_personality); |
4687 | register_md_personality(&raid4_personality); | |
4688 | return 0; | |
1da177e4 LT |
4689 | } |
4690 | ||
2604b703 | 4691 | static void raid5_exit(void) |
1da177e4 | 4692 | { |
16a53ecc | 4693 | unregister_md_personality(&raid6_personality); |
2604b703 N |
4694 | unregister_md_personality(&raid5_personality); |
4695 | unregister_md_personality(&raid4_personality); | |
1da177e4 LT |
4696 | } |
4697 | ||
4698 | module_init(raid5_init); | |
4699 | module_exit(raid5_exit); | |
4700 | MODULE_LICENSE("GPL"); | |
4701 | MODULE_ALIAS("md-personality-4"); /* RAID5 */ | |
d9d166c2 N |
4702 | MODULE_ALIAS("md-raid5"); |
4703 | MODULE_ALIAS("md-raid4"); | |
2604b703 N |
4704 | MODULE_ALIAS("md-level-5"); |
4705 | MODULE_ALIAS("md-level-4"); | |
16a53ecc N |
4706 | MODULE_ALIAS("md-personality-8"); /* RAID6 */ |
4707 | MODULE_ALIAS("md-raid6"); | |
4708 | MODULE_ALIAS("md-level-6"); | |
4709 | ||
4710 | /* This used to be two separate modules, they were: */ | |
4711 | MODULE_ALIAS("raid5"); | |
4712 | MODULE_ALIAS("raid6"); |