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 | ||
858119e1 | 125 | static void __release_stripe(raid5_conf_t *conf, struct stripe_head *sh) |
1da177e4 LT |
126 | { |
127 | if (atomic_dec_and_test(&sh->count)) { | |
78bafebd ES |
128 | BUG_ON(!list_empty(&sh->lru)); |
129 | BUG_ON(atomic_read(&conf->active_stripes)==0); | |
1da177e4 | 130 | if (test_bit(STRIPE_HANDLE, &sh->state)) { |
7c785b7a | 131 | if (test_bit(STRIPE_DELAYED, &sh->state)) { |
1da177e4 | 132 | list_add_tail(&sh->lru, &conf->delayed_list); |
7c785b7a N |
133 | blk_plug_device(conf->mddev->queue); |
134 | } else if (test_bit(STRIPE_BIT_DELAY, &sh->state) && | |
ae3c20cc | 135 | sh->bm_seq - conf->seq_write > 0) { |
72626685 | 136 | list_add_tail(&sh->lru, &conf->bitmap_list); |
7c785b7a N |
137 | blk_plug_device(conf->mddev->queue); |
138 | } else { | |
72626685 | 139 | clear_bit(STRIPE_BIT_DELAY, &sh->state); |
1da177e4 | 140 | list_add_tail(&sh->lru, &conf->handle_list); |
72626685 | 141 | } |
1da177e4 LT |
142 | md_wakeup_thread(conf->mddev->thread); |
143 | } else { | |
d84e0f10 | 144 | BUG_ON(sh->ops.pending); |
1da177e4 LT |
145 | if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { |
146 | atomic_dec(&conf->preread_active_stripes); | |
147 | if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD) | |
148 | md_wakeup_thread(conf->mddev->thread); | |
149 | } | |
1da177e4 | 150 | atomic_dec(&conf->active_stripes); |
ccfcc3c1 N |
151 | if (!test_bit(STRIPE_EXPANDING, &sh->state)) { |
152 | list_add_tail(&sh->lru, &conf->inactive_list); | |
1da177e4 | 153 | wake_up(&conf->wait_for_stripe); |
46031f9a RBJ |
154 | if (conf->retry_read_aligned) |
155 | md_wakeup_thread(conf->mddev->thread); | |
ccfcc3c1 | 156 | } |
1da177e4 LT |
157 | } |
158 | } | |
159 | } | |
160 | static void release_stripe(struct stripe_head *sh) | |
161 | { | |
162 | raid5_conf_t *conf = sh->raid_conf; | |
163 | unsigned long flags; | |
16a53ecc | 164 | |
1da177e4 LT |
165 | spin_lock_irqsave(&conf->device_lock, flags); |
166 | __release_stripe(conf, sh); | |
167 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
168 | } | |
169 | ||
fccddba0 | 170 | static inline void remove_hash(struct stripe_head *sh) |
1da177e4 | 171 | { |
45b4233c DW |
172 | pr_debug("remove_hash(), stripe %llu\n", |
173 | (unsigned long long)sh->sector); | |
1da177e4 | 174 | |
fccddba0 | 175 | hlist_del_init(&sh->hash); |
1da177e4 LT |
176 | } |
177 | ||
16a53ecc | 178 | static inline void insert_hash(raid5_conf_t *conf, struct stripe_head *sh) |
1da177e4 | 179 | { |
fccddba0 | 180 | struct hlist_head *hp = stripe_hash(conf, sh->sector); |
1da177e4 | 181 | |
45b4233c DW |
182 | pr_debug("insert_hash(), stripe %llu\n", |
183 | (unsigned long long)sh->sector); | |
1da177e4 LT |
184 | |
185 | CHECK_DEVLOCK(); | |
fccddba0 | 186 | hlist_add_head(&sh->hash, hp); |
1da177e4 LT |
187 | } |
188 | ||
189 | ||
190 | /* find an idle stripe, make sure it is unhashed, and return it. */ | |
191 | static struct stripe_head *get_free_stripe(raid5_conf_t *conf) | |
192 | { | |
193 | struct stripe_head *sh = NULL; | |
194 | struct list_head *first; | |
195 | ||
196 | CHECK_DEVLOCK(); | |
197 | if (list_empty(&conf->inactive_list)) | |
198 | goto out; | |
199 | first = conf->inactive_list.next; | |
200 | sh = list_entry(first, struct stripe_head, lru); | |
201 | list_del_init(first); | |
202 | remove_hash(sh); | |
203 | atomic_inc(&conf->active_stripes); | |
204 | out: | |
205 | return sh; | |
206 | } | |
207 | ||
208 | static void shrink_buffers(struct stripe_head *sh, int num) | |
209 | { | |
210 | struct page *p; | |
211 | int i; | |
212 | ||
213 | for (i=0; i<num ; i++) { | |
214 | p = sh->dev[i].page; | |
215 | if (!p) | |
216 | continue; | |
217 | sh->dev[i].page = NULL; | |
2d1f3b5d | 218 | put_page(p); |
1da177e4 LT |
219 | } |
220 | } | |
221 | ||
222 | static int grow_buffers(struct stripe_head *sh, int num) | |
223 | { | |
224 | int i; | |
225 | ||
226 | for (i=0; i<num; i++) { | |
227 | struct page *page; | |
228 | ||
229 | if (!(page = alloc_page(GFP_KERNEL))) { | |
230 | return 1; | |
231 | } | |
232 | sh->dev[i].page = page; | |
233 | } | |
234 | return 0; | |
235 | } | |
236 | ||
237 | static void raid5_build_block (struct stripe_head *sh, int i); | |
238 | ||
7ecaa1e6 | 239 | static void init_stripe(struct stripe_head *sh, sector_t sector, int pd_idx, int disks) |
1da177e4 LT |
240 | { |
241 | raid5_conf_t *conf = sh->raid_conf; | |
7ecaa1e6 | 242 | int i; |
1da177e4 | 243 | |
78bafebd ES |
244 | BUG_ON(atomic_read(&sh->count) != 0); |
245 | BUG_ON(test_bit(STRIPE_HANDLE, &sh->state)); | |
d84e0f10 DW |
246 | BUG_ON(sh->ops.pending || sh->ops.ack || sh->ops.complete); |
247 | ||
1da177e4 | 248 | CHECK_DEVLOCK(); |
45b4233c | 249 | pr_debug("init_stripe called, stripe %llu\n", |
1da177e4 LT |
250 | (unsigned long long)sh->sector); |
251 | ||
252 | remove_hash(sh); | |
16a53ecc | 253 | |
1da177e4 LT |
254 | sh->sector = sector; |
255 | sh->pd_idx = pd_idx; | |
256 | sh->state = 0; | |
257 | ||
7ecaa1e6 N |
258 | sh->disks = disks; |
259 | ||
260 | for (i = sh->disks; i--; ) { | |
1da177e4 LT |
261 | struct r5dev *dev = &sh->dev[i]; |
262 | ||
d84e0f10 | 263 | if (dev->toread || dev->read || dev->towrite || dev->written || |
1da177e4 | 264 | test_bit(R5_LOCKED, &dev->flags)) { |
d84e0f10 | 265 | printk(KERN_ERR "sector=%llx i=%d %p %p %p %p %d\n", |
1da177e4 | 266 | (unsigned long long)sh->sector, i, dev->toread, |
d84e0f10 | 267 | dev->read, dev->towrite, dev->written, |
1da177e4 LT |
268 | test_bit(R5_LOCKED, &dev->flags)); |
269 | BUG(); | |
270 | } | |
271 | dev->flags = 0; | |
272 | raid5_build_block(sh, i); | |
273 | } | |
274 | insert_hash(conf, sh); | |
275 | } | |
276 | ||
7ecaa1e6 | 277 | static struct stripe_head *__find_stripe(raid5_conf_t *conf, sector_t sector, int disks) |
1da177e4 LT |
278 | { |
279 | struct stripe_head *sh; | |
fccddba0 | 280 | struct hlist_node *hn; |
1da177e4 LT |
281 | |
282 | CHECK_DEVLOCK(); | |
45b4233c | 283 | pr_debug("__find_stripe, sector %llu\n", (unsigned long long)sector); |
fccddba0 | 284 | hlist_for_each_entry(sh, hn, stripe_hash(conf, sector), hash) |
7ecaa1e6 | 285 | if (sh->sector == sector && sh->disks == disks) |
1da177e4 | 286 | return sh; |
45b4233c | 287 | pr_debug("__stripe %llu not in cache\n", (unsigned long long)sector); |
1da177e4 LT |
288 | return NULL; |
289 | } | |
290 | ||
291 | static void unplug_slaves(mddev_t *mddev); | |
165125e1 | 292 | static void raid5_unplug_device(struct request_queue *q); |
1da177e4 | 293 | |
7ecaa1e6 N |
294 | static struct stripe_head *get_active_stripe(raid5_conf_t *conf, sector_t sector, int disks, |
295 | int pd_idx, int noblock) | |
1da177e4 LT |
296 | { |
297 | struct stripe_head *sh; | |
298 | ||
45b4233c | 299 | pr_debug("get_stripe, sector %llu\n", (unsigned long long)sector); |
1da177e4 LT |
300 | |
301 | spin_lock_irq(&conf->device_lock); | |
302 | ||
303 | do { | |
72626685 N |
304 | wait_event_lock_irq(conf->wait_for_stripe, |
305 | conf->quiesce == 0, | |
306 | conf->device_lock, /* nothing */); | |
7ecaa1e6 | 307 | sh = __find_stripe(conf, sector, disks); |
1da177e4 LT |
308 | if (!sh) { |
309 | if (!conf->inactive_blocked) | |
310 | sh = get_free_stripe(conf); | |
311 | if (noblock && sh == NULL) | |
312 | break; | |
313 | if (!sh) { | |
314 | conf->inactive_blocked = 1; | |
315 | wait_event_lock_irq(conf->wait_for_stripe, | |
316 | !list_empty(&conf->inactive_list) && | |
5036805b N |
317 | (atomic_read(&conf->active_stripes) |
318 | < (conf->max_nr_stripes *3/4) | |
1da177e4 LT |
319 | || !conf->inactive_blocked), |
320 | conf->device_lock, | |
f4370781 | 321 | raid5_unplug_device(conf->mddev->queue) |
1da177e4 LT |
322 | ); |
323 | conf->inactive_blocked = 0; | |
324 | } else | |
7ecaa1e6 | 325 | init_stripe(sh, sector, pd_idx, disks); |
1da177e4 LT |
326 | } else { |
327 | if (atomic_read(&sh->count)) { | |
78bafebd | 328 | BUG_ON(!list_empty(&sh->lru)); |
1da177e4 LT |
329 | } else { |
330 | if (!test_bit(STRIPE_HANDLE, &sh->state)) | |
331 | atomic_inc(&conf->active_stripes); | |
ff4e8d9a N |
332 | if (list_empty(&sh->lru) && |
333 | !test_bit(STRIPE_EXPANDING, &sh->state)) | |
16a53ecc N |
334 | BUG(); |
335 | list_del_init(&sh->lru); | |
1da177e4 LT |
336 | } |
337 | } | |
338 | } while (sh == NULL); | |
339 | ||
340 | if (sh) | |
341 | atomic_inc(&sh->count); | |
342 | ||
343 | spin_unlock_irq(&conf->device_lock); | |
344 | return sh; | |
345 | } | |
346 | ||
d84e0f10 DW |
347 | /* test_and_ack_op() ensures that we only dequeue an operation once */ |
348 | #define test_and_ack_op(op, pend) \ | |
349 | do { \ | |
350 | if (test_bit(op, &sh->ops.pending) && \ | |
351 | !test_bit(op, &sh->ops.complete)) { \ | |
352 | if (test_and_set_bit(op, &sh->ops.ack)) \ | |
353 | clear_bit(op, &pend); \ | |
354 | else \ | |
355 | ack++; \ | |
356 | } else \ | |
357 | clear_bit(op, &pend); \ | |
358 | } while (0) | |
359 | ||
360 | /* find new work to run, do not resubmit work that is already | |
361 | * in flight | |
362 | */ | |
363 | static unsigned long get_stripe_work(struct stripe_head *sh) | |
364 | { | |
365 | unsigned long pending; | |
366 | int ack = 0; | |
367 | ||
368 | pending = sh->ops.pending; | |
369 | ||
370 | test_and_ack_op(STRIPE_OP_BIOFILL, pending); | |
371 | test_and_ack_op(STRIPE_OP_COMPUTE_BLK, pending); | |
372 | test_and_ack_op(STRIPE_OP_PREXOR, pending); | |
373 | test_and_ack_op(STRIPE_OP_BIODRAIN, pending); | |
374 | test_and_ack_op(STRIPE_OP_POSTXOR, pending); | |
375 | test_and_ack_op(STRIPE_OP_CHECK, pending); | |
376 | if (test_and_clear_bit(STRIPE_OP_IO, &sh->ops.pending)) | |
377 | ack++; | |
378 | ||
379 | sh->ops.count -= ack; | |
4ae3f847 DW |
380 | if (unlikely(sh->ops.count < 0)) { |
381 | printk(KERN_ERR "pending: %#lx ops.pending: %#lx ops.ack: %#lx " | |
382 | "ops.complete: %#lx\n", pending, sh->ops.pending, | |
383 | sh->ops.ack, sh->ops.complete); | |
384 | BUG(); | |
385 | } | |
d84e0f10 DW |
386 | |
387 | return pending; | |
388 | } | |
389 | ||
6712ecf8 N |
390 | static void |
391 | raid5_end_read_request(struct bio *bi, int error); | |
392 | static void | |
393 | raid5_end_write_request(struct bio *bi, int error); | |
91c00924 DW |
394 | |
395 | static void ops_run_io(struct stripe_head *sh) | |
396 | { | |
397 | raid5_conf_t *conf = sh->raid_conf; | |
398 | int i, disks = sh->disks; | |
399 | ||
400 | might_sleep(); | |
401 | ||
8b3e6cdc | 402 | set_bit(STRIPE_IO_STARTED, &sh->state); |
91c00924 DW |
403 | for (i = disks; i--; ) { |
404 | int rw; | |
405 | struct bio *bi; | |
406 | mdk_rdev_t *rdev; | |
407 | if (test_and_clear_bit(R5_Wantwrite, &sh->dev[i].flags)) | |
408 | rw = WRITE; | |
409 | else if (test_and_clear_bit(R5_Wantread, &sh->dev[i].flags)) | |
410 | rw = READ; | |
411 | else | |
412 | continue; | |
413 | ||
414 | bi = &sh->dev[i].req; | |
415 | ||
416 | bi->bi_rw = rw; | |
417 | if (rw == WRITE) | |
418 | bi->bi_end_io = raid5_end_write_request; | |
419 | else | |
420 | bi->bi_end_io = raid5_end_read_request; | |
421 | ||
422 | rcu_read_lock(); | |
423 | rdev = rcu_dereference(conf->disks[i].rdev); | |
424 | if (rdev && test_bit(Faulty, &rdev->flags)) | |
425 | rdev = NULL; | |
426 | if (rdev) | |
427 | atomic_inc(&rdev->nr_pending); | |
428 | rcu_read_unlock(); | |
429 | ||
430 | if (rdev) { | |
431 | if (test_bit(STRIPE_SYNCING, &sh->state) || | |
432 | test_bit(STRIPE_EXPAND_SOURCE, &sh->state) || | |
433 | test_bit(STRIPE_EXPAND_READY, &sh->state)) | |
434 | md_sync_acct(rdev->bdev, STRIPE_SECTORS); | |
435 | ||
436 | bi->bi_bdev = rdev->bdev; | |
437 | pr_debug("%s: for %llu schedule op %ld on disc %d\n", | |
e46b272b | 438 | __func__, (unsigned long long)sh->sector, |
91c00924 DW |
439 | bi->bi_rw, i); |
440 | atomic_inc(&sh->count); | |
441 | bi->bi_sector = sh->sector + rdev->data_offset; | |
442 | bi->bi_flags = 1 << BIO_UPTODATE; | |
443 | bi->bi_vcnt = 1; | |
444 | bi->bi_max_vecs = 1; | |
445 | bi->bi_idx = 0; | |
446 | bi->bi_io_vec = &sh->dev[i].vec; | |
447 | bi->bi_io_vec[0].bv_len = STRIPE_SIZE; | |
448 | bi->bi_io_vec[0].bv_offset = 0; | |
449 | bi->bi_size = STRIPE_SIZE; | |
450 | bi->bi_next = NULL; | |
451 | if (rw == WRITE && | |
452 | test_bit(R5_ReWrite, &sh->dev[i].flags)) | |
453 | atomic_add(STRIPE_SECTORS, | |
454 | &rdev->corrected_errors); | |
455 | generic_make_request(bi); | |
456 | } else { | |
457 | if (rw == WRITE) | |
458 | set_bit(STRIPE_DEGRADED, &sh->state); | |
459 | pr_debug("skip op %ld on disc %d for sector %llu\n", | |
460 | bi->bi_rw, i, (unsigned long long)sh->sector); | |
461 | clear_bit(R5_LOCKED, &sh->dev[i].flags); | |
462 | set_bit(STRIPE_HANDLE, &sh->state); | |
463 | } | |
464 | } | |
465 | } | |
466 | ||
467 | static struct dma_async_tx_descriptor * | |
468 | async_copy_data(int frombio, struct bio *bio, struct page *page, | |
469 | sector_t sector, struct dma_async_tx_descriptor *tx) | |
470 | { | |
471 | struct bio_vec *bvl; | |
472 | struct page *bio_page; | |
473 | int i; | |
474 | int page_offset; | |
475 | ||
476 | if (bio->bi_sector >= sector) | |
477 | page_offset = (signed)(bio->bi_sector - sector) * 512; | |
478 | else | |
479 | page_offset = (signed)(sector - bio->bi_sector) * -512; | |
480 | bio_for_each_segment(bvl, bio, i) { | |
481 | int len = bio_iovec_idx(bio, i)->bv_len; | |
482 | int clen; | |
483 | int b_offset = 0; | |
484 | ||
485 | if (page_offset < 0) { | |
486 | b_offset = -page_offset; | |
487 | page_offset += b_offset; | |
488 | len -= b_offset; | |
489 | } | |
490 | ||
491 | if (len > 0 && page_offset + len > STRIPE_SIZE) | |
492 | clen = STRIPE_SIZE - page_offset; | |
493 | else | |
494 | clen = len; | |
495 | ||
496 | if (clen > 0) { | |
497 | b_offset += bio_iovec_idx(bio, i)->bv_offset; | |
498 | bio_page = bio_iovec_idx(bio, i)->bv_page; | |
499 | if (frombio) | |
500 | tx = async_memcpy(page, bio_page, page_offset, | |
501 | b_offset, clen, | |
eb0645a8 | 502 | ASYNC_TX_DEP_ACK, |
91c00924 DW |
503 | tx, NULL, NULL); |
504 | else | |
505 | tx = async_memcpy(bio_page, page, b_offset, | |
506 | page_offset, clen, | |
eb0645a8 | 507 | ASYNC_TX_DEP_ACK, |
91c00924 DW |
508 | tx, NULL, NULL); |
509 | } | |
510 | if (clen < len) /* hit end of page */ | |
511 | break; | |
512 | page_offset += len; | |
513 | } | |
514 | ||
515 | return tx; | |
516 | } | |
517 | ||
518 | static void ops_complete_biofill(void *stripe_head_ref) | |
519 | { | |
520 | struct stripe_head *sh = stripe_head_ref; | |
521 | struct bio *return_bi = NULL; | |
522 | raid5_conf_t *conf = sh->raid_conf; | |
e4d84909 | 523 | int i; |
91c00924 | 524 | |
e46b272b | 525 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
526 | (unsigned long long)sh->sector); |
527 | ||
528 | /* clear completed biofills */ | |
529 | for (i = sh->disks; i--; ) { | |
530 | struct r5dev *dev = &sh->dev[i]; | |
91c00924 DW |
531 | |
532 | /* acknowledge completion of a biofill operation */ | |
e4d84909 DW |
533 | /* and check if we need to reply to a read request, |
534 | * new R5_Wantfill requests are held off until | |
535 | * !test_bit(STRIPE_OP_BIOFILL, &sh->ops.pending) | |
536 | */ | |
537 | if (test_and_clear_bit(R5_Wantfill, &dev->flags)) { | |
91c00924 | 538 | struct bio *rbi, *rbi2; |
91c00924 DW |
539 | |
540 | /* The access to dev->read is outside of the | |
541 | * spin_lock_irq(&conf->device_lock), but is protected | |
542 | * by the STRIPE_OP_BIOFILL pending bit | |
543 | */ | |
544 | BUG_ON(!dev->read); | |
545 | rbi = dev->read; | |
546 | dev->read = NULL; | |
547 | while (rbi && rbi->bi_sector < | |
548 | dev->sector + STRIPE_SECTORS) { | |
549 | rbi2 = r5_next_bio(rbi, dev->sector); | |
550 | spin_lock_irq(&conf->device_lock); | |
551 | if (--rbi->bi_phys_segments == 0) { | |
552 | rbi->bi_next = return_bi; | |
553 | return_bi = rbi; | |
554 | } | |
555 | spin_unlock_irq(&conf->device_lock); | |
556 | rbi = rbi2; | |
557 | } | |
558 | } | |
559 | } | |
4ae3f847 | 560 | set_bit(STRIPE_OP_BIOFILL, &sh->ops.complete); |
91c00924 DW |
561 | |
562 | return_io(return_bi); | |
563 | ||
e4d84909 | 564 | set_bit(STRIPE_HANDLE, &sh->state); |
91c00924 DW |
565 | release_stripe(sh); |
566 | } | |
567 | ||
568 | static void ops_run_biofill(struct stripe_head *sh) | |
569 | { | |
570 | struct dma_async_tx_descriptor *tx = NULL; | |
571 | raid5_conf_t *conf = sh->raid_conf; | |
572 | int i; | |
573 | ||
e46b272b | 574 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
575 | (unsigned long long)sh->sector); |
576 | ||
577 | for (i = sh->disks; i--; ) { | |
578 | struct r5dev *dev = &sh->dev[i]; | |
579 | if (test_bit(R5_Wantfill, &dev->flags)) { | |
580 | struct bio *rbi; | |
581 | spin_lock_irq(&conf->device_lock); | |
582 | dev->read = rbi = dev->toread; | |
583 | dev->toread = NULL; | |
584 | spin_unlock_irq(&conf->device_lock); | |
585 | while (rbi && rbi->bi_sector < | |
586 | dev->sector + STRIPE_SECTORS) { | |
587 | tx = async_copy_data(0, rbi, dev->page, | |
588 | dev->sector, tx); | |
589 | rbi = r5_next_bio(rbi, dev->sector); | |
590 | } | |
591 | } | |
592 | } | |
593 | ||
594 | atomic_inc(&sh->count); | |
595 | async_trigger_callback(ASYNC_TX_DEP_ACK | ASYNC_TX_ACK, tx, | |
596 | ops_complete_biofill, sh); | |
597 | } | |
598 | ||
599 | static void ops_complete_compute5(void *stripe_head_ref) | |
600 | { | |
601 | struct stripe_head *sh = stripe_head_ref; | |
602 | int target = sh->ops.target; | |
603 | struct r5dev *tgt = &sh->dev[target]; | |
604 | ||
e46b272b | 605 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
606 | (unsigned long long)sh->sector); |
607 | ||
608 | set_bit(R5_UPTODATE, &tgt->flags); | |
609 | BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags)); | |
610 | clear_bit(R5_Wantcompute, &tgt->flags); | |
611 | set_bit(STRIPE_OP_COMPUTE_BLK, &sh->ops.complete); | |
612 | set_bit(STRIPE_HANDLE, &sh->state); | |
613 | release_stripe(sh); | |
614 | } | |
615 | ||
616 | static struct dma_async_tx_descriptor * | |
617 | ops_run_compute5(struct stripe_head *sh, unsigned long pending) | |
618 | { | |
619 | /* kernel stack size limits the total number of disks */ | |
620 | int disks = sh->disks; | |
621 | struct page *xor_srcs[disks]; | |
622 | int target = sh->ops.target; | |
623 | struct r5dev *tgt = &sh->dev[target]; | |
624 | struct page *xor_dest = tgt->page; | |
625 | int count = 0; | |
626 | struct dma_async_tx_descriptor *tx; | |
627 | int i; | |
628 | ||
629 | pr_debug("%s: stripe %llu block: %d\n", | |
e46b272b | 630 | __func__, (unsigned long long)sh->sector, target); |
91c00924 DW |
631 | BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags)); |
632 | ||
633 | for (i = disks; i--; ) | |
634 | if (i != target) | |
635 | xor_srcs[count++] = sh->dev[i].page; | |
636 | ||
637 | atomic_inc(&sh->count); | |
638 | ||
639 | if (unlikely(count == 1)) | |
640 | tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE, | |
641 | 0, NULL, ops_complete_compute5, sh); | |
642 | else | |
643 | tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, | |
644 | ASYNC_TX_XOR_ZERO_DST, NULL, | |
645 | ops_complete_compute5, sh); | |
646 | ||
647 | /* ack now if postxor is not set to be run */ | |
648 | if (tx && !test_bit(STRIPE_OP_POSTXOR, &pending)) | |
649 | async_tx_ack(tx); | |
650 | ||
651 | return tx; | |
652 | } | |
653 | ||
654 | static void ops_complete_prexor(void *stripe_head_ref) | |
655 | { | |
656 | struct stripe_head *sh = stripe_head_ref; | |
657 | ||
e46b272b | 658 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
659 | (unsigned long long)sh->sector); |
660 | ||
661 | set_bit(STRIPE_OP_PREXOR, &sh->ops.complete); | |
662 | } | |
663 | ||
664 | static struct dma_async_tx_descriptor * | |
665 | ops_run_prexor(struct stripe_head *sh, struct dma_async_tx_descriptor *tx) | |
666 | { | |
667 | /* kernel stack size limits the total number of disks */ | |
668 | int disks = sh->disks; | |
669 | struct page *xor_srcs[disks]; | |
670 | int count = 0, pd_idx = sh->pd_idx, i; | |
671 | ||
672 | /* existing parity data subtracted */ | |
673 | struct page *xor_dest = xor_srcs[count++] = sh->dev[pd_idx].page; | |
674 | ||
e46b272b | 675 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
676 | (unsigned long long)sh->sector); |
677 | ||
678 | for (i = disks; i--; ) { | |
679 | struct r5dev *dev = &sh->dev[i]; | |
680 | /* Only process blocks that are known to be uptodate */ | |
681 | if (dev->towrite && test_bit(R5_Wantprexor, &dev->flags)) | |
682 | xor_srcs[count++] = dev->page; | |
683 | } | |
684 | ||
685 | tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, | |
686 | ASYNC_TX_DEP_ACK | ASYNC_TX_XOR_DROP_DST, tx, | |
687 | ops_complete_prexor, sh); | |
688 | ||
689 | return tx; | |
690 | } | |
691 | ||
692 | static struct dma_async_tx_descriptor * | |
6c55be8b DW |
693 | ops_run_biodrain(struct stripe_head *sh, struct dma_async_tx_descriptor *tx, |
694 | unsigned long pending) | |
91c00924 DW |
695 | { |
696 | int disks = sh->disks; | |
697 | int pd_idx = sh->pd_idx, i; | |
698 | ||
699 | /* check if prexor is active which means only process blocks | |
700 | * that are part of a read-modify-write (Wantprexor) | |
701 | */ | |
6c55be8b | 702 | int prexor = test_bit(STRIPE_OP_PREXOR, &pending); |
91c00924 | 703 | |
e46b272b | 704 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
705 | (unsigned long long)sh->sector); |
706 | ||
707 | for (i = disks; i--; ) { | |
708 | struct r5dev *dev = &sh->dev[i]; | |
709 | struct bio *chosen; | |
710 | int towrite; | |
711 | ||
712 | towrite = 0; | |
713 | if (prexor) { /* rmw */ | |
714 | if (dev->towrite && | |
715 | test_bit(R5_Wantprexor, &dev->flags)) | |
716 | towrite = 1; | |
717 | } else { /* rcw */ | |
718 | if (i != pd_idx && dev->towrite && | |
719 | test_bit(R5_LOCKED, &dev->flags)) | |
720 | towrite = 1; | |
721 | } | |
722 | ||
723 | if (towrite) { | |
724 | struct bio *wbi; | |
725 | ||
726 | spin_lock(&sh->lock); | |
727 | chosen = dev->towrite; | |
728 | dev->towrite = NULL; | |
729 | BUG_ON(dev->written); | |
730 | wbi = dev->written = chosen; | |
731 | spin_unlock(&sh->lock); | |
732 | ||
733 | while (wbi && wbi->bi_sector < | |
734 | dev->sector + STRIPE_SECTORS) { | |
735 | tx = async_copy_data(1, wbi, dev->page, | |
736 | dev->sector, tx); | |
737 | wbi = r5_next_bio(wbi, dev->sector); | |
738 | } | |
739 | } | |
740 | } | |
741 | ||
742 | return tx; | |
743 | } | |
744 | ||
745 | static void ops_complete_postxor(void *stripe_head_ref) | |
746 | { | |
747 | struct stripe_head *sh = stripe_head_ref; | |
748 | ||
e46b272b | 749 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
750 | (unsigned long long)sh->sector); |
751 | ||
752 | set_bit(STRIPE_OP_POSTXOR, &sh->ops.complete); | |
753 | set_bit(STRIPE_HANDLE, &sh->state); | |
754 | release_stripe(sh); | |
755 | } | |
756 | ||
757 | static void ops_complete_write(void *stripe_head_ref) | |
758 | { | |
759 | struct stripe_head *sh = stripe_head_ref; | |
760 | int disks = sh->disks, i, pd_idx = sh->pd_idx; | |
761 | ||
e46b272b | 762 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
763 | (unsigned long long)sh->sector); |
764 | ||
765 | for (i = disks; i--; ) { | |
766 | struct r5dev *dev = &sh->dev[i]; | |
767 | if (dev->written || i == pd_idx) | |
768 | set_bit(R5_UPTODATE, &dev->flags); | |
769 | } | |
770 | ||
771 | set_bit(STRIPE_OP_BIODRAIN, &sh->ops.complete); | |
772 | set_bit(STRIPE_OP_POSTXOR, &sh->ops.complete); | |
773 | ||
774 | set_bit(STRIPE_HANDLE, &sh->state); | |
775 | release_stripe(sh); | |
776 | } | |
777 | ||
778 | static void | |
6c55be8b DW |
779 | ops_run_postxor(struct stripe_head *sh, struct dma_async_tx_descriptor *tx, |
780 | unsigned long pending) | |
91c00924 DW |
781 | { |
782 | /* kernel stack size limits the total number of disks */ | |
783 | int disks = sh->disks; | |
784 | struct page *xor_srcs[disks]; | |
785 | ||
786 | int count = 0, pd_idx = sh->pd_idx, i; | |
787 | struct page *xor_dest; | |
6c55be8b | 788 | int prexor = test_bit(STRIPE_OP_PREXOR, &pending); |
91c00924 DW |
789 | unsigned long flags; |
790 | dma_async_tx_callback callback; | |
791 | ||
e46b272b | 792 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
793 | (unsigned long long)sh->sector); |
794 | ||
795 | /* check if prexor is active which means only process blocks | |
796 | * that are part of a read-modify-write (written) | |
797 | */ | |
798 | if (prexor) { | |
799 | xor_dest = xor_srcs[count++] = sh->dev[pd_idx].page; | |
800 | for (i = disks; i--; ) { | |
801 | struct r5dev *dev = &sh->dev[i]; | |
802 | if (dev->written) | |
803 | xor_srcs[count++] = dev->page; | |
804 | } | |
805 | } else { | |
806 | xor_dest = sh->dev[pd_idx].page; | |
807 | for (i = disks; i--; ) { | |
808 | struct r5dev *dev = &sh->dev[i]; | |
809 | if (i != pd_idx) | |
810 | xor_srcs[count++] = dev->page; | |
811 | } | |
812 | } | |
813 | ||
814 | /* check whether this postxor is part of a write */ | |
6c55be8b | 815 | callback = test_bit(STRIPE_OP_BIODRAIN, &pending) ? |
91c00924 DW |
816 | ops_complete_write : ops_complete_postxor; |
817 | ||
818 | /* 1/ if we prexor'd then the dest is reused as a source | |
819 | * 2/ if we did not prexor then we are redoing the parity | |
820 | * set ASYNC_TX_XOR_DROP_DST and ASYNC_TX_XOR_ZERO_DST | |
821 | * for the synchronous xor case | |
822 | */ | |
823 | flags = ASYNC_TX_DEP_ACK | ASYNC_TX_ACK | | |
824 | (prexor ? ASYNC_TX_XOR_DROP_DST : ASYNC_TX_XOR_ZERO_DST); | |
825 | ||
826 | atomic_inc(&sh->count); | |
827 | ||
828 | if (unlikely(count == 1)) { | |
829 | flags &= ~(ASYNC_TX_XOR_DROP_DST | ASYNC_TX_XOR_ZERO_DST); | |
830 | tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE, | |
831 | flags, tx, callback, sh); | |
832 | } else | |
833 | tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, | |
834 | flags, tx, callback, sh); | |
835 | } | |
836 | ||
837 | static void ops_complete_check(void *stripe_head_ref) | |
838 | { | |
839 | struct stripe_head *sh = stripe_head_ref; | |
91c00924 | 840 | |
e46b272b | 841 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
842 | (unsigned long long)sh->sector); |
843 | ||
91c00924 DW |
844 | set_bit(STRIPE_OP_CHECK, &sh->ops.complete); |
845 | set_bit(STRIPE_HANDLE, &sh->state); | |
846 | release_stripe(sh); | |
847 | } | |
848 | ||
849 | static void ops_run_check(struct stripe_head *sh) | |
850 | { | |
851 | /* kernel stack size limits the total number of disks */ | |
852 | int disks = sh->disks; | |
853 | struct page *xor_srcs[disks]; | |
854 | struct dma_async_tx_descriptor *tx; | |
855 | ||
856 | int count = 0, pd_idx = sh->pd_idx, i; | |
857 | struct page *xor_dest = xor_srcs[count++] = sh->dev[pd_idx].page; | |
858 | ||
e46b272b | 859 | pr_debug("%s: stripe %llu\n", __func__, |
91c00924 DW |
860 | (unsigned long long)sh->sector); |
861 | ||
862 | for (i = disks; i--; ) { | |
863 | struct r5dev *dev = &sh->dev[i]; | |
864 | if (i != pd_idx) | |
865 | xor_srcs[count++] = dev->page; | |
866 | } | |
867 | ||
868 | tx = async_xor_zero_sum(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, | |
869 | &sh->ops.zero_sum_result, 0, NULL, NULL, NULL); | |
870 | ||
91c00924 DW |
871 | atomic_inc(&sh->count); |
872 | tx = async_trigger_callback(ASYNC_TX_DEP_ACK | ASYNC_TX_ACK, tx, | |
873 | ops_complete_check, sh); | |
874 | } | |
875 | ||
876 | static void raid5_run_ops(struct stripe_head *sh, unsigned long pending) | |
877 | { | |
878 | int overlap_clear = 0, i, disks = sh->disks; | |
879 | struct dma_async_tx_descriptor *tx = NULL; | |
880 | ||
881 | if (test_bit(STRIPE_OP_BIOFILL, &pending)) { | |
882 | ops_run_biofill(sh); | |
883 | overlap_clear++; | |
884 | } | |
885 | ||
886 | if (test_bit(STRIPE_OP_COMPUTE_BLK, &pending)) | |
887 | tx = ops_run_compute5(sh, pending); | |
888 | ||
889 | if (test_bit(STRIPE_OP_PREXOR, &pending)) | |
890 | tx = ops_run_prexor(sh, tx); | |
891 | ||
892 | if (test_bit(STRIPE_OP_BIODRAIN, &pending)) { | |
6c55be8b | 893 | tx = ops_run_biodrain(sh, tx, pending); |
91c00924 DW |
894 | overlap_clear++; |
895 | } | |
896 | ||
897 | if (test_bit(STRIPE_OP_POSTXOR, &pending)) | |
6c55be8b | 898 | ops_run_postxor(sh, tx, pending); |
91c00924 DW |
899 | |
900 | if (test_bit(STRIPE_OP_CHECK, &pending)) | |
901 | ops_run_check(sh); | |
902 | ||
903 | if (test_bit(STRIPE_OP_IO, &pending)) | |
904 | ops_run_io(sh); | |
905 | ||
906 | if (overlap_clear) | |
907 | for (i = disks; i--; ) { | |
908 | struct r5dev *dev = &sh->dev[i]; | |
909 | if (test_and_clear_bit(R5_Overlap, &dev->flags)) | |
910 | wake_up(&sh->raid_conf->wait_for_overlap); | |
911 | } | |
912 | } | |
913 | ||
3f294f4f | 914 | static int grow_one_stripe(raid5_conf_t *conf) |
1da177e4 LT |
915 | { |
916 | struct stripe_head *sh; | |
3f294f4f N |
917 | sh = kmem_cache_alloc(conf->slab_cache, GFP_KERNEL); |
918 | if (!sh) | |
919 | return 0; | |
920 | memset(sh, 0, sizeof(*sh) + (conf->raid_disks-1)*sizeof(struct r5dev)); | |
921 | sh->raid_conf = conf; | |
922 | spin_lock_init(&sh->lock); | |
923 | ||
924 | if (grow_buffers(sh, conf->raid_disks)) { | |
925 | shrink_buffers(sh, conf->raid_disks); | |
926 | kmem_cache_free(conf->slab_cache, sh); | |
927 | return 0; | |
928 | } | |
7ecaa1e6 | 929 | sh->disks = conf->raid_disks; |
3f294f4f N |
930 | /* we just created an active stripe so... */ |
931 | atomic_set(&sh->count, 1); | |
932 | atomic_inc(&conf->active_stripes); | |
933 | INIT_LIST_HEAD(&sh->lru); | |
934 | release_stripe(sh); | |
935 | return 1; | |
936 | } | |
937 | ||
938 | static int grow_stripes(raid5_conf_t *conf, int num) | |
939 | { | |
e18b890b | 940 | struct kmem_cache *sc; |
1da177e4 LT |
941 | int devs = conf->raid_disks; |
942 | ||
42b9bebe N |
943 | sprintf(conf->cache_name[0], "raid5-%s", mdname(conf->mddev)); |
944 | sprintf(conf->cache_name[1], "raid5-%s-alt", mdname(conf->mddev)); | |
ad01c9e3 N |
945 | conf->active_name = 0; |
946 | sc = kmem_cache_create(conf->cache_name[conf->active_name], | |
1da177e4 | 947 | sizeof(struct stripe_head)+(devs-1)*sizeof(struct r5dev), |
20c2df83 | 948 | 0, 0, NULL); |
1da177e4 LT |
949 | if (!sc) |
950 | return 1; | |
951 | conf->slab_cache = sc; | |
ad01c9e3 | 952 | conf->pool_size = devs; |
16a53ecc | 953 | while (num--) |
3f294f4f | 954 | if (!grow_one_stripe(conf)) |
1da177e4 | 955 | return 1; |
1da177e4 LT |
956 | return 0; |
957 | } | |
29269553 N |
958 | |
959 | #ifdef CONFIG_MD_RAID5_RESHAPE | |
ad01c9e3 N |
960 | static int resize_stripes(raid5_conf_t *conf, int newsize) |
961 | { | |
962 | /* Make all the stripes able to hold 'newsize' devices. | |
963 | * New slots in each stripe get 'page' set to a new page. | |
964 | * | |
965 | * This happens in stages: | |
966 | * 1/ create a new kmem_cache and allocate the required number of | |
967 | * stripe_heads. | |
968 | * 2/ gather all the old stripe_heads and tranfer the pages across | |
969 | * to the new stripe_heads. This will have the side effect of | |
970 | * freezing the array as once all stripe_heads have been collected, | |
971 | * no IO will be possible. Old stripe heads are freed once their | |
972 | * pages have been transferred over, and the old kmem_cache is | |
973 | * freed when all stripes are done. | |
974 | * 3/ reallocate conf->disks to be suitable bigger. If this fails, | |
975 | * we simple return a failre status - no need to clean anything up. | |
976 | * 4/ allocate new pages for the new slots in the new stripe_heads. | |
977 | * If this fails, we don't bother trying the shrink the | |
978 | * stripe_heads down again, we just leave them as they are. | |
979 | * As each stripe_head is processed the new one is released into | |
980 | * active service. | |
981 | * | |
982 | * Once step2 is started, we cannot afford to wait for a write, | |
983 | * so we use GFP_NOIO allocations. | |
984 | */ | |
985 | struct stripe_head *osh, *nsh; | |
986 | LIST_HEAD(newstripes); | |
987 | struct disk_info *ndisks; | |
988 | int err = 0; | |
e18b890b | 989 | struct kmem_cache *sc; |
ad01c9e3 N |
990 | int i; |
991 | ||
992 | if (newsize <= conf->pool_size) | |
993 | return 0; /* never bother to shrink */ | |
994 | ||
2a2275d6 N |
995 | md_allow_write(conf->mddev); |
996 | ||
ad01c9e3 N |
997 | /* Step 1 */ |
998 | sc = kmem_cache_create(conf->cache_name[1-conf->active_name], | |
999 | sizeof(struct stripe_head)+(newsize-1)*sizeof(struct r5dev), | |
20c2df83 | 1000 | 0, 0, NULL); |
ad01c9e3 N |
1001 | if (!sc) |
1002 | return -ENOMEM; | |
1003 | ||
1004 | for (i = conf->max_nr_stripes; i; i--) { | |
1005 | nsh = kmem_cache_alloc(sc, GFP_KERNEL); | |
1006 | if (!nsh) | |
1007 | break; | |
1008 | ||
1009 | memset(nsh, 0, sizeof(*nsh) + (newsize-1)*sizeof(struct r5dev)); | |
1010 | ||
1011 | nsh->raid_conf = conf; | |
1012 | spin_lock_init(&nsh->lock); | |
1013 | ||
1014 | list_add(&nsh->lru, &newstripes); | |
1015 | } | |
1016 | if (i) { | |
1017 | /* didn't get enough, give up */ | |
1018 | while (!list_empty(&newstripes)) { | |
1019 | nsh = list_entry(newstripes.next, struct stripe_head, lru); | |
1020 | list_del(&nsh->lru); | |
1021 | kmem_cache_free(sc, nsh); | |
1022 | } | |
1023 | kmem_cache_destroy(sc); | |
1024 | return -ENOMEM; | |
1025 | } | |
1026 | /* Step 2 - Must use GFP_NOIO now. | |
1027 | * OK, we have enough stripes, start collecting inactive | |
1028 | * stripes and copying them over | |
1029 | */ | |
1030 | list_for_each_entry(nsh, &newstripes, lru) { | |
1031 | spin_lock_irq(&conf->device_lock); | |
1032 | wait_event_lock_irq(conf->wait_for_stripe, | |
1033 | !list_empty(&conf->inactive_list), | |
1034 | conf->device_lock, | |
b3b46be3 | 1035 | unplug_slaves(conf->mddev) |
ad01c9e3 N |
1036 | ); |
1037 | osh = get_free_stripe(conf); | |
1038 | spin_unlock_irq(&conf->device_lock); | |
1039 | atomic_set(&nsh->count, 1); | |
1040 | for(i=0; i<conf->pool_size; i++) | |
1041 | nsh->dev[i].page = osh->dev[i].page; | |
1042 | for( ; i<newsize; i++) | |
1043 | nsh->dev[i].page = NULL; | |
1044 | kmem_cache_free(conf->slab_cache, osh); | |
1045 | } | |
1046 | kmem_cache_destroy(conf->slab_cache); | |
1047 | ||
1048 | /* Step 3. | |
1049 | * At this point, we are holding all the stripes so the array | |
1050 | * is completely stalled, so now is a good time to resize | |
1051 | * conf->disks. | |
1052 | */ | |
1053 | ndisks = kzalloc(newsize * sizeof(struct disk_info), GFP_NOIO); | |
1054 | if (ndisks) { | |
1055 | for (i=0; i<conf->raid_disks; i++) | |
1056 | ndisks[i] = conf->disks[i]; | |
1057 | kfree(conf->disks); | |
1058 | conf->disks = ndisks; | |
1059 | } else | |
1060 | err = -ENOMEM; | |
1061 | ||
1062 | /* Step 4, return new stripes to service */ | |
1063 | while(!list_empty(&newstripes)) { | |
1064 | nsh = list_entry(newstripes.next, struct stripe_head, lru); | |
1065 | list_del_init(&nsh->lru); | |
1066 | for (i=conf->raid_disks; i < newsize; i++) | |
1067 | if (nsh->dev[i].page == NULL) { | |
1068 | struct page *p = alloc_page(GFP_NOIO); | |
1069 | nsh->dev[i].page = p; | |
1070 | if (!p) | |
1071 | err = -ENOMEM; | |
1072 | } | |
1073 | release_stripe(nsh); | |
1074 | } | |
1075 | /* critical section pass, GFP_NOIO no longer needed */ | |
1076 | ||
1077 | conf->slab_cache = sc; | |
1078 | conf->active_name = 1-conf->active_name; | |
1079 | conf->pool_size = newsize; | |
1080 | return err; | |
1081 | } | |
29269553 | 1082 | #endif |
1da177e4 | 1083 | |
3f294f4f | 1084 | static int drop_one_stripe(raid5_conf_t *conf) |
1da177e4 LT |
1085 | { |
1086 | struct stripe_head *sh; | |
1087 | ||
3f294f4f N |
1088 | spin_lock_irq(&conf->device_lock); |
1089 | sh = get_free_stripe(conf); | |
1090 | spin_unlock_irq(&conf->device_lock); | |
1091 | if (!sh) | |
1092 | return 0; | |
78bafebd | 1093 | BUG_ON(atomic_read(&sh->count)); |
ad01c9e3 | 1094 | shrink_buffers(sh, conf->pool_size); |
3f294f4f N |
1095 | kmem_cache_free(conf->slab_cache, sh); |
1096 | atomic_dec(&conf->active_stripes); | |
1097 | return 1; | |
1098 | } | |
1099 | ||
1100 | static void shrink_stripes(raid5_conf_t *conf) | |
1101 | { | |
1102 | while (drop_one_stripe(conf)) | |
1103 | ; | |
1104 | ||
29fc7e3e N |
1105 | if (conf->slab_cache) |
1106 | kmem_cache_destroy(conf->slab_cache); | |
1da177e4 LT |
1107 | conf->slab_cache = NULL; |
1108 | } | |
1109 | ||
6712ecf8 | 1110 | static void raid5_end_read_request(struct bio * bi, int error) |
1da177e4 LT |
1111 | { |
1112 | struct stripe_head *sh = bi->bi_private; | |
1113 | raid5_conf_t *conf = sh->raid_conf; | |
7ecaa1e6 | 1114 | int disks = sh->disks, i; |
1da177e4 | 1115 | int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags); |
d6950432 N |
1116 | char b[BDEVNAME_SIZE]; |
1117 | mdk_rdev_t *rdev; | |
1da177e4 | 1118 | |
1da177e4 LT |
1119 | |
1120 | for (i=0 ; i<disks; i++) | |
1121 | if (bi == &sh->dev[i].req) | |
1122 | break; | |
1123 | ||
45b4233c DW |
1124 | pr_debug("end_read_request %llu/%d, count: %d, uptodate %d.\n", |
1125 | (unsigned long long)sh->sector, i, atomic_read(&sh->count), | |
1da177e4 LT |
1126 | uptodate); |
1127 | if (i == disks) { | |
1128 | BUG(); | |
6712ecf8 | 1129 | return; |
1da177e4 LT |
1130 | } |
1131 | ||
1132 | if (uptodate) { | |
1da177e4 | 1133 | set_bit(R5_UPTODATE, &sh->dev[i].flags); |
4e5314b5 | 1134 | if (test_bit(R5_ReadError, &sh->dev[i].flags)) { |
d6950432 | 1135 | rdev = conf->disks[i].rdev; |
6be9d494 BS |
1136 | printk_rl(KERN_INFO "raid5:%s: read error corrected" |
1137 | " (%lu sectors at %llu on %s)\n", | |
1138 | mdname(conf->mddev), STRIPE_SECTORS, | |
1139 | (unsigned long long)(sh->sector | |
1140 | + rdev->data_offset), | |
1141 | bdevname(rdev->bdev, b)); | |
4e5314b5 N |
1142 | clear_bit(R5_ReadError, &sh->dev[i].flags); |
1143 | clear_bit(R5_ReWrite, &sh->dev[i].flags); | |
1144 | } | |
ba22dcbf N |
1145 | if (atomic_read(&conf->disks[i].rdev->read_errors)) |
1146 | atomic_set(&conf->disks[i].rdev->read_errors, 0); | |
1da177e4 | 1147 | } else { |
d6950432 | 1148 | const char *bdn = bdevname(conf->disks[i].rdev->bdev, b); |
ba22dcbf | 1149 | int retry = 0; |
d6950432 N |
1150 | rdev = conf->disks[i].rdev; |
1151 | ||
1da177e4 | 1152 | clear_bit(R5_UPTODATE, &sh->dev[i].flags); |
d6950432 | 1153 | atomic_inc(&rdev->read_errors); |
ba22dcbf | 1154 | if (conf->mddev->degraded) |
6be9d494 BS |
1155 | printk_rl(KERN_WARNING |
1156 | "raid5:%s: read error not correctable " | |
1157 | "(sector %llu on %s).\n", | |
1158 | mdname(conf->mddev), | |
1159 | (unsigned long long)(sh->sector | |
1160 | + rdev->data_offset), | |
1161 | bdn); | |
ba22dcbf | 1162 | else if (test_bit(R5_ReWrite, &sh->dev[i].flags)) |
4e5314b5 | 1163 | /* Oh, no!!! */ |
6be9d494 BS |
1164 | printk_rl(KERN_WARNING |
1165 | "raid5:%s: read error NOT corrected!! " | |
1166 | "(sector %llu on %s).\n", | |
1167 | mdname(conf->mddev), | |
1168 | (unsigned long long)(sh->sector | |
1169 | + rdev->data_offset), | |
1170 | bdn); | |
d6950432 | 1171 | else if (atomic_read(&rdev->read_errors) |
ba22dcbf | 1172 | > conf->max_nr_stripes) |
14f8d26b | 1173 | printk(KERN_WARNING |
d6950432 N |
1174 | "raid5:%s: Too many read errors, failing device %s.\n", |
1175 | mdname(conf->mddev), bdn); | |
ba22dcbf N |
1176 | else |
1177 | retry = 1; | |
1178 | if (retry) | |
1179 | set_bit(R5_ReadError, &sh->dev[i].flags); | |
1180 | else { | |
4e5314b5 N |
1181 | clear_bit(R5_ReadError, &sh->dev[i].flags); |
1182 | clear_bit(R5_ReWrite, &sh->dev[i].flags); | |
d6950432 | 1183 | md_error(conf->mddev, rdev); |
ba22dcbf | 1184 | } |
1da177e4 LT |
1185 | } |
1186 | rdev_dec_pending(conf->disks[i].rdev, conf->mddev); | |
1da177e4 LT |
1187 | clear_bit(R5_LOCKED, &sh->dev[i].flags); |
1188 | set_bit(STRIPE_HANDLE, &sh->state); | |
1189 | release_stripe(sh); | |
1da177e4 LT |
1190 | } |
1191 | ||
6712ecf8 | 1192 | static void raid5_end_write_request (struct bio *bi, int error) |
1da177e4 LT |
1193 | { |
1194 | struct stripe_head *sh = bi->bi_private; | |
1195 | raid5_conf_t *conf = sh->raid_conf; | |
7ecaa1e6 | 1196 | int disks = sh->disks, i; |
1da177e4 LT |
1197 | int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags); |
1198 | ||
1da177e4 LT |
1199 | for (i=0 ; i<disks; i++) |
1200 | if (bi == &sh->dev[i].req) | |
1201 | break; | |
1202 | ||
45b4233c | 1203 | pr_debug("end_write_request %llu/%d, count %d, uptodate: %d.\n", |
1da177e4 LT |
1204 | (unsigned long long)sh->sector, i, atomic_read(&sh->count), |
1205 | uptodate); | |
1206 | if (i == disks) { | |
1207 | BUG(); | |
6712ecf8 | 1208 | return; |
1da177e4 LT |
1209 | } |
1210 | ||
1da177e4 LT |
1211 | if (!uptodate) |
1212 | md_error(conf->mddev, conf->disks[i].rdev); | |
1213 | ||
1214 | rdev_dec_pending(conf->disks[i].rdev, conf->mddev); | |
1215 | ||
1216 | clear_bit(R5_LOCKED, &sh->dev[i].flags); | |
1217 | set_bit(STRIPE_HANDLE, &sh->state); | |
c04be0aa | 1218 | release_stripe(sh); |
1da177e4 LT |
1219 | } |
1220 | ||
1221 | ||
1222 | static sector_t compute_blocknr(struct stripe_head *sh, int i); | |
1223 | ||
1224 | static void raid5_build_block (struct stripe_head *sh, int i) | |
1225 | { | |
1226 | struct r5dev *dev = &sh->dev[i]; | |
1227 | ||
1228 | bio_init(&dev->req); | |
1229 | dev->req.bi_io_vec = &dev->vec; | |
1230 | dev->req.bi_vcnt++; | |
1231 | dev->req.bi_max_vecs++; | |
1232 | dev->vec.bv_page = dev->page; | |
1233 | dev->vec.bv_len = STRIPE_SIZE; | |
1234 | dev->vec.bv_offset = 0; | |
1235 | ||
1236 | dev->req.bi_sector = sh->sector; | |
1237 | dev->req.bi_private = sh; | |
1238 | ||
1239 | dev->flags = 0; | |
16a53ecc | 1240 | dev->sector = compute_blocknr(sh, i); |
1da177e4 LT |
1241 | } |
1242 | ||
1243 | static void error(mddev_t *mddev, mdk_rdev_t *rdev) | |
1244 | { | |
1245 | char b[BDEVNAME_SIZE]; | |
1246 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; | |
45b4233c | 1247 | pr_debug("raid5: error called\n"); |
1da177e4 | 1248 | |
b2d444d7 | 1249 | if (!test_bit(Faulty, &rdev->flags)) { |
850b2b42 | 1250 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
c04be0aa N |
1251 | if (test_and_clear_bit(In_sync, &rdev->flags)) { |
1252 | unsigned long flags; | |
1253 | spin_lock_irqsave(&conf->device_lock, flags); | |
1da177e4 | 1254 | mddev->degraded++; |
c04be0aa | 1255 | spin_unlock_irqrestore(&conf->device_lock, flags); |
1da177e4 LT |
1256 | /* |
1257 | * if recovery was running, make sure it aborts. | |
1258 | */ | |
dfc70645 | 1259 | set_bit(MD_RECOVERY_INTR, &mddev->recovery); |
1da177e4 | 1260 | } |
b2d444d7 | 1261 | set_bit(Faulty, &rdev->flags); |
1da177e4 | 1262 | printk (KERN_ALERT |
d7a420c9 NA |
1263 | "raid5: Disk failure on %s, disabling device.\n" |
1264 | "raid5: Operation continuing on %d devices.\n", | |
02c2de8c | 1265 | bdevname(rdev->bdev,b), conf->raid_disks - mddev->degraded); |
1da177e4 | 1266 | } |
16a53ecc | 1267 | } |
1da177e4 LT |
1268 | |
1269 | /* | |
1270 | * Input: a 'big' sector number, | |
1271 | * Output: index of the data and parity disk, and the sector # in them. | |
1272 | */ | |
1273 | static sector_t raid5_compute_sector(sector_t r_sector, unsigned int raid_disks, | |
1274 | unsigned int data_disks, unsigned int * dd_idx, | |
1275 | unsigned int * pd_idx, raid5_conf_t *conf) | |
1276 | { | |
1277 | long stripe; | |
1278 | unsigned long chunk_number; | |
1279 | unsigned int chunk_offset; | |
1280 | sector_t new_sector; | |
1281 | int sectors_per_chunk = conf->chunk_size >> 9; | |
1282 | ||
1283 | /* First compute the information on this sector */ | |
1284 | ||
1285 | /* | |
1286 | * Compute the chunk number and the sector offset inside the chunk | |
1287 | */ | |
1288 | chunk_offset = sector_div(r_sector, sectors_per_chunk); | |
1289 | chunk_number = r_sector; | |
1290 | BUG_ON(r_sector != chunk_number); | |
1291 | ||
1292 | /* | |
1293 | * Compute the stripe number | |
1294 | */ | |
1295 | stripe = chunk_number / data_disks; | |
1296 | ||
1297 | /* | |
1298 | * Compute the data disk and parity disk indexes inside the stripe | |
1299 | */ | |
1300 | *dd_idx = chunk_number % data_disks; | |
1301 | ||
1302 | /* | |
1303 | * Select the parity disk based on the user selected algorithm. | |
1304 | */ | |
16a53ecc N |
1305 | switch(conf->level) { |
1306 | case 4: | |
1da177e4 | 1307 | *pd_idx = data_disks; |
16a53ecc N |
1308 | break; |
1309 | case 5: | |
1310 | switch (conf->algorithm) { | |
1da177e4 LT |
1311 | case ALGORITHM_LEFT_ASYMMETRIC: |
1312 | *pd_idx = data_disks - stripe % raid_disks; | |
1313 | if (*dd_idx >= *pd_idx) | |
1314 | (*dd_idx)++; | |
1315 | break; | |
1316 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
1317 | *pd_idx = stripe % raid_disks; | |
1318 | if (*dd_idx >= *pd_idx) | |
1319 | (*dd_idx)++; | |
1320 | break; | |
1321 | case ALGORITHM_LEFT_SYMMETRIC: | |
1322 | *pd_idx = data_disks - stripe % raid_disks; | |
1323 | *dd_idx = (*pd_idx + 1 + *dd_idx) % raid_disks; | |
1324 | break; | |
1325 | case ALGORITHM_RIGHT_SYMMETRIC: | |
1326 | *pd_idx = stripe % raid_disks; | |
1327 | *dd_idx = (*pd_idx + 1 + *dd_idx) % raid_disks; | |
1328 | break; | |
1329 | default: | |
14f8d26b | 1330 | printk(KERN_ERR "raid5: unsupported algorithm %d\n", |
1da177e4 | 1331 | conf->algorithm); |
16a53ecc N |
1332 | } |
1333 | break; | |
1334 | case 6: | |
1335 | ||
1336 | /**** FIX THIS ****/ | |
1337 | switch (conf->algorithm) { | |
1338 | case ALGORITHM_LEFT_ASYMMETRIC: | |
1339 | *pd_idx = raid_disks - 1 - (stripe % raid_disks); | |
1340 | if (*pd_idx == raid_disks-1) | |
1341 | (*dd_idx)++; /* Q D D D P */ | |
1342 | else if (*dd_idx >= *pd_idx) | |
1343 | (*dd_idx) += 2; /* D D P Q D */ | |
1344 | break; | |
1345 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
1346 | *pd_idx = stripe % raid_disks; | |
1347 | if (*pd_idx == raid_disks-1) | |
1348 | (*dd_idx)++; /* Q D D D P */ | |
1349 | else if (*dd_idx >= *pd_idx) | |
1350 | (*dd_idx) += 2; /* D D P Q D */ | |
1351 | break; | |
1352 | case ALGORITHM_LEFT_SYMMETRIC: | |
1353 | *pd_idx = raid_disks - 1 - (stripe % raid_disks); | |
1354 | *dd_idx = (*pd_idx + 2 + *dd_idx) % raid_disks; | |
1355 | break; | |
1356 | case ALGORITHM_RIGHT_SYMMETRIC: | |
1357 | *pd_idx = stripe % raid_disks; | |
1358 | *dd_idx = (*pd_idx + 2 + *dd_idx) % raid_disks; | |
1359 | break; | |
1360 | default: | |
1361 | printk (KERN_CRIT "raid6: unsupported algorithm %d\n", | |
1362 | conf->algorithm); | |
1363 | } | |
1364 | break; | |
1da177e4 LT |
1365 | } |
1366 | ||
1367 | /* | |
1368 | * Finally, compute the new sector number | |
1369 | */ | |
1370 | new_sector = (sector_t)stripe * sectors_per_chunk + chunk_offset; | |
1371 | return new_sector; | |
1372 | } | |
1373 | ||
1374 | ||
1375 | static sector_t compute_blocknr(struct stripe_head *sh, int i) | |
1376 | { | |
1377 | raid5_conf_t *conf = sh->raid_conf; | |
b875e531 N |
1378 | int raid_disks = sh->disks; |
1379 | int data_disks = raid_disks - conf->max_degraded; | |
1da177e4 LT |
1380 | sector_t new_sector = sh->sector, check; |
1381 | int sectors_per_chunk = conf->chunk_size >> 9; | |
1382 | sector_t stripe; | |
1383 | int chunk_offset; | |
1384 | int chunk_number, dummy1, dummy2, dd_idx = i; | |
1385 | sector_t r_sector; | |
1386 | ||
16a53ecc | 1387 | |
1da177e4 LT |
1388 | chunk_offset = sector_div(new_sector, sectors_per_chunk); |
1389 | stripe = new_sector; | |
1390 | BUG_ON(new_sector != stripe); | |
1391 | ||
16a53ecc N |
1392 | if (i == sh->pd_idx) |
1393 | return 0; | |
1394 | switch(conf->level) { | |
1395 | case 4: break; | |
1396 | case 5: | |
1397 | switch (conf->algorithm) { | |
1da177e4 LT |
1398 | case ALGORITHM_LEFT_ASYMMETRIC: |
1399 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
1400 | if (i > sh->pd_idx) | |
1401 | i--; | |
1402 | break; | |
1403 | case ALGORITHM_LEFT_SYMMETRIC: | |
1404 | case ALGORITHM_RIGHT_SYMMETRIC: | |
1405 | if (i < sh->pd_idx) | |
1406 | i += raid_disks; | |
1407 | i -= (sh->pd_idx + 1); | |
1408 | break; | |
1409 | default: | |
14f8d26b | 1410 | printk(KERN_ERR "raid5: unsupported algorithm %d\n", |
16a53ecc N |
1411 | conf->algorithm); |
1412 | } | |
1413 | break; | |
1414 | case 6: | |
16a53ecc N |
1415 | if (i == raid6_next_disk(sh->pd_idx, raid_disks)) |
1416 | return 0; /* It is the Q disk */ | |
1417 | switch (conf->algorithm) { | |
1418 | case ALGORITHM_LEFT_ASYMMETRIC: | |
1419 | case ALGORITHM_RIGHT_ASYMMETRIC: | |
1420 | if (sh->pd_idx == raid_disks-1) | |
1421 | i--; /* Q D D D P */ | |
1422 | else if (i > sh->pd_idx) | |
1423 | i -= 2; /* D D P Q D */ | |
1424 | break; | |
1425 | case ALGORITHM_LEFT_SYMMETRIC: | |
1426 | case ALGORITHM_RIGHT_SYMMETRIC: | |
1427 | if (sh->pd_idx == raid_disks-1) | |
1428 | i--; /* Q D D D P */ | |
1429 | else { | |
1430 | /* D D P Q D */ | |
1431 | if (i < sh->pd_idx) | |
1432 | i += raid_disks; | |
1433 | i -= (sh->pd_idx + 2); | |
1434 | } | |
1435 | break; | |
1436 | default: | |
1437 | printk (KERN_CRIT "raid6: unsupported algorithm %d\n", | |
1da177e4 | 1438 | conf->algorithm); |
16a53ecc N |
1439 | } |
1440 | break; | |
1da177e4 LT |
1441 | } |
1442 | ||
1443 | chunk_number = stripe * data_disks + i; | |
1444 | r_sector = (sector_t)chunk_number * sectors_per_chunk + chunk_offset; | |
1445 | ||
1446 | check = raid5_compute_sector (r_sector, raid_disks, data_disks, &dummy1, &dummy2, conf); | |
1447 | if (check != sh->sector || dummy1 != dd_idx || dummy2 != sh->pd_idx) { | |
14f8d26b | 1448 | printk(KERN_ERR "compute_blocknr: map not correct\n"); |
1da177e4 LT |
1449 | return 0; |
1450 | } | |
1451 | return r_sector; | |
1452 | } | |
1453 | ||
1454 | ||
1455 | ||
1456 | /* | |
16a53ecc N |
1457 | * Copy data between a page in the stripe cache, and one or more bion |
1458 | * The page could align with the middle of the bio, or there could be | |
1459 | * several bion, each with several bio_vecs, which cover part of the page | |
1460 | * Multiple bion are linked together on bi_next. There may be extras | |
1461 | * at the end of this list. We ignore them. | |
1da177e4 LT |
1462 | */ |
1463 | static void copy_data(int frombio, struct bio *bio, | |
1464 | struct page *page, | |
1465 | sector_t sector) | |
1466 | { | |
1467 | char *pa = page_address(page); | |
1468 | struct bio_vec *bvl; | |
1469 | int i; | |
1470 | int page_offset; | |
1471 | ||
1472 | if (bio->bi_sector >= sector) | |
1473 | page_offset = (signed)(bio->bi_sector - sector) * 512; | |
1474 | else | |
1475 | page_offset = (signed)(sector - bio->bi_sector) * -512; | |
1476 | bio_for_each_segment(bvl, bio, i) { | |
1477 | int len = bio_iovec_idx(bio,i)->bv_len; | |
1478 | int clen; | |
1479 | int b_offset = 0; | |
1480 | ||
1481 | if (page_offset < 0) { | |
1482 | b_offset = -page_offset; | |
1483 | page_offset += b_offset; | |
1484 | len -= b_offset; | |
1485 | } | |
1486 | ||
1487 | if (len > 0 && page_offset + len > STRIPE_SIZE) | |
1488 | clen = STRIPE_SIZE - page_offset; | |
1489 | else clen = len; | |
16a53ecc | 1490 | |
1da177e4 LT |
1491 | if (clen > 0) { |
1492 | char *ba = __bio_kmap_atomic(bio, i, KM_USER0); | |
1493 | if (frombio) | |
1494 | memcpy(pa+page_offset, ba+b_offset, clen); | |
1495 | else | |
1496 | memcpy(ba+b_offset, pa+page_offset, clen); | |
1497 | __bio_kunmap_atomic(ba, KM_USER0); | |
1498 | } | |
1499 | if (clen < len) /* hit end of page */ | |
1500 | break; | |
1501 | page_offset += len; | |
1502 | } | |
1503 | } | |
1504 | ||
9bc89cd8 DW |
1505 | #define check_xor() do { \ |
1506 | if (count == MAX_XOR_BLOCKS) { \ | |
1507 | xor_blocks(count, STRIPE_SIZE, dest, ptr);\ | |
1508 | count = 0; \ | |
1509 | } \ | |
1da177e4 LT |
1510 | } while(0) |
1511 | ||
16a53ecc N |
1512 | static void compute_parity6(struct stripe_head *sh, int method) |
1513 | { | |
1514 | raid6_conf_t *conf = sh->raid_conf; | |
f416885e | 1515 | int i, pd_idx = sh->pd_idx, qd_idx, d0_idx, disks = sh->disks, count; |
16a53ecc N |
1516 | struct bio *chosen; |
1517 | /**** FIX THIS: This could be very bad if disks is close to 256 ****/ | |
1518 | void *ptrs[disks]; | |
1519 | ||
1520 | qd_idx = raid6_next_disk(pd_idx, disks); | |
1521 | d0_idx = raid6_next_disk(qd_idx, disks); | |
1522 | ||
45b4233c | 1523 | pr_debug("compute_parity, stripe %llu, method %d\n", |
16a53ecc N |
1524 | (unsigned long long)sh->sector, method); |
1525 | ||
1526 | switch(method) { | |
1527 | case READ_MODIFY_WRITE: | |
1528 | BUG(); /* READ_MODIFY_WRITE N/A for RAID-6 */ | |
1529 | case RECONSTRUCT_WRITE: | |
1530 | for (i= disks; i-- ;) | |
1531 | if ( i != pd_idx && i != qd_idx && sh->dev[i].towrite ) { | |
1532 | chosen = sh->dev[i].towrite; | |
1533 | sh->dev[i].towrite = NULL; | |
1534 | ||
1535 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) | |
1536 | wake_up(&conf->wait_for_overlap); | |
1537 | ||
52e5f9d1 | 1538 | BUG_ON(sh->dev[i].written); |
16a53ecc N |
1539 | sh->dev[i].written = chosen; |
1540 | } | |
1541 | break; | |
1542 | case CHECK_PARITY: | |
1543 | BUG(); /* Not implemented yet */ | |
1544 | } | |
1545 | ||
1546 | for (i = disks; i--;) | |
1547 | if (sh->dev[i].written) { | |
1548 | sector_t sector = sh->dev[i].sector; | |
1549 | struct bio *wbi = sh->dev[i].written; | |
1550 | while (wbi && wbi->bi_sector < sector + STRIPE_SECTORS) { | |
1551 | copy_data(1, wbi, sh->dev[i].page, sector); | |
1552 | wbi = r5_next_bio(wbi, sector); | |
1553 | } | |
1554 | ||
1555 | set_bit(R5_LOCKED, &sh->dev[i].flags); | |
1556 | set_bit(R5_UPTODATE, &sh->dev[i].flags); | |
1557 | } | |
1558 | ||
1559 | // switch(method) { | |
1560 | // case RECONSTRUCT_WRITE: | |
1561 | // case CHECK_PARITY: | |
1562 | // case UPDATE_PARITY: | |
1563 | /* Note that unlike RAID-5, the ordering of the disks matters greatly. */ | |
1564 | /* FIX: Is this ordering of drives even remotely optimal? */ | |
1565 | count = 0; | |
1566 | i = d0_idx; | |
1567 | do { | |
1568 | ptrs[count++] = page_address(sh->dev[i].page); | |
1569 | if (count <= disks-2 && !test_bit(R5_UPTODATE, &sh->dev[i].flags)) | |
1570 | printk("block %d/%d not uptodate on parity calc\n", i,count); | |
1571 | i = raid6_next_disk(i, disks); | |
1572 | } while ( i != d0_idx ); | |
1573 | // break; | |
1574 | // } | |
1575 | ||
1576 | raid6_call.gen_syndrome(disks, STRIPE_SIZE, ptrs); | |
1577 | ||
1578 | switch(method) { | |
1579 | case RECONSTRUCT_WRITE: | |
1580 | set_bit(R5_UPTODATE, &sh->dev[pd_idx].flags); | |
1581 | set_bit(R5_UPTODATE, &sh->dev[qd_idx].flags); | |
1582 | set_bit(R5_LOCKED, &sh->dev[pd_idx].flags); | |
1583 | set_bit(R5_LOCKED, &sh->dev[qd_idx].flags); | |
1584 | break; | |
1585 | case UPDATE_PARITY: | |
1586 | set_bit(R5_UPTODATE, &sh->dev[pd_idx].flags); | |
1587 | set_bit(R5_UPTODATE, &sh->dev[qd_idx].flags); | |
1588 | break; | |
1589 | } | |
1590 | } | |
1591 | ||
1592 | ||
1593 | /* Compute one missing block */ | |
1594 | static void compute_block_1(struct stripe_head *sh, int dd_idx, int nozero) | |
1595 | { | |
f416885e | 1596 | int i, count, disks = sh->disks; |
9bc89cd8 | 1597 | void *ptr[MAX_XOR_BLOCKS], *dest, *p; |
16a53ecc N |
1598 | int pd_idx = sh->pd_idx; |
1599 | int qd_idx = raid6_next_disk(pd_idx, disks); | |
1600 | ||
45b4233c | 1601 | pr_debug("compute_block_1, stripe %llu, idx %d\n", |
16a53ecc N |
1602 | (unsigned long long)sh->sector, dd_idx); |
1603 | ||
1604 | if ( dd_idx == qd_idx ) { | |
1605 | /* We're actually computing the Q drive */ | |
1606 | compute_parity6(sh, UPDATE_PARITY); | |
1607 | } else { | |
9bc89cd8 DW |
1608 | dest = page_address(sh->dev[dd_idx].page); |
1609 | if (!nozero) memset(dest, 0, STRIPE_SIZE); | |
1610 | count = 0; | |
16a53ecc N |
1611 | for (i = disks ; i--; ) { |
1612 | if (i == dd_idx || i == qd_idx) | |
1613 | continue; | |
1614 | p = page_address(sh->dev[i].page); | |
1615 | if (test_bit(R5_UPTODATE, &sh->dev[i].flags)) | |
1616 | ptr[count++] = p; | |
1617 | else | |
1618 | printk("compute_block() %d, stripe %llu, %d" | |
1619 | " not present\n", dd_idx, | |
1620 | (unsigned long long)sh->sector, i); | |
1621 | ||
1622 | check_xor(); | |
1623 | } | |
9bc89cd8 DW |
1624 | if (count) |
1625 | xor_blocks(count, STRIPE_SIZE, dest, ptr); | |
16a53ecc N |
1626 | if (!nozero) set_bit(R5_UPTODATE, &sh->dev[dd_idx].flags); |
1627 | else clear_bit(R5_UPTODATE, &sh->dev[dd_idx].flags); | |
1628 | } | |
1629 | } | |
1630 | ||
1631 | /* Compute two missing blocks */ | |
1632 | static void compute_block_2(struct stripe_head *sh, int dd_idx1, int dd_idx2) | |
1633 | { | |
f416885e | 1634 | int i, count, disks = sh->disks; |
16a53ecc N |
1635 | int pd_idx = sh->pd_idx; |
1636 | int qd_idx = raid6_next_disk(pd_idx, disks); | |
1637 | int d0_idx = raid6_next_disk(qd_idx, disks); | |
1638 | int faila, failb; | |
1639 | ||
1640 | /* faila and failb are disk numbers relative to d0_idx */ | |
1641 | /* pd_idx become disks-2 and qd_idx become disks-1 */ | |
1642 | faila = (dd_idx1 < d0_idx) ? dd_idx1+(disks-d0_idx) : dd_idx1-d0_idx; | |
1643 | failb = (dd_idx2 < d0_idx) ? dd_idx2+(disks-d0_idx) : dd_idx2-d0_idx; | |
1644 | ||
1645 | BUG_ON(faila == failb); | |
1646 | if ( failb < faila ) { int tmp = faila; faila = failb; failb = tmp; } | |
1647 | ||
45b4233c | 1648 | pr_debug("compute_block_2, stripe %llu, idx %d,%d (%d,%d)\n", |
16a53ecc N |
1649 | (unsigned long long)sh->sector, dd_idx1, dd_idx2, faila, failb); |
1650 | ||
1651 | if ( failb == disks-1 ) { | |
1652 | /* Q disk is one of the missing disks */ | |
1653 | if ( faila == disks-2 ) { | |
1654 | /* Missing P+Q, just recompute */ | |
1655 | compute_parity6(sh, UPDATE_PARITY); | |
1656 | return; | |
1657 | } else { | |
1658 | /* We're missing D+Q; recompute D from P */ | |
1659 | compute_block_1(sh, (dd_idx1 == qd_idx) ? dd_idx2 : dd_idx1, 0); | |
1660 | compute_parity6(sh, UPDATE_PARITY); /* Is this necessary? */ | |
1661 | return; | |
1662 | } | |
1663 | } | |
1664 | ||
1665 | /* We're missing D+P or D+D; build pointer table */ | |
1666 | { | |
1667 | /**** FIX THIS: This could be very bad if disks is close to 256 ****/ | |
1668 | void *ptrs[disks]; | |
1669 | ||
1670 | count = 0; | |
1671 | i = d0_idx; | |
1672 | do { | |
1673 | ptrs[count++] = page_address(sh->dev[i].page); | |
1674 | i = raid6_next_disk(i, disks); | |
1675 | if (i != dd_idx1 && i != dd_idx2 && | |
1676 | !test_bit(R5_UPTODATE, &sh->dev[i].flags)) | |
1677 | printk("compute_2 with missing block %d/%d\n", count, i); | |
1678 | } while ( i != d0_idx ); | |
1679 | ||
1680 | if ( failb == disks-2 ) { | |
1681 | /* We're missing D+P. */ | |
1682 | raid6_datap_recov(disks, STRIPE_SIZE, faila, ptrs); | |
1683 | } else { | |
1684 | /* We're missing D+D. */ | |
1685 | raid6_2data_recov(disks, STRIPE_SIZE, faila, failb, ptrs); | |
1686 | } | |
1687 | ||
1688 | /* Both the above update both missing blocks */ | |
1689 | set_bit(R5_UPTODATE, &sh->dev[dd_idx1].flags); | |
1690 | set_bit(R5_UPTODATE, &sh->dev[dd_idx2].flags); | |
1691 | } | |
1692 | } | |
1693 | ||
e33129d8 DW |
1694 | static int |
1695 | handle_write_operations5(struct stripe_head *sh, int rcw, int expand) | |
1696 | { | |
1697 | int i, pd_idx = sh->pd_idx, disks = sh->disks; | |
1698 | int locked = 0; | |
1699 | ||
1700 | if (rcw) { | |
1701 | /* if we are not expanding this is a proper write request, and | |
1702 | * there will be bios with new data to be drained into the | |
1703 | * stripe cache | |
1704 | */ | |
1705 | if (!expand) { | |
1706 | set_bit(STRIPE_OP_BIODRAIN, &sh->ops.pending); | |
1707 | sh->ops.count++; | |
1708 | } | |
16a53ecc | 1709 | |
e33129d8 DW |
1710 | set_bit(STRIPE_OP_POSTXOR, &sh->ops.pending); |
1711 | sh->ops.count++; | |
1712 | ||
1713 | for (i = disks; i--; ) { | |
1714 | struct r5dev *dev = &sh->dev[i]; | |
1715 | ||
1716 | if (dev->towrite) { | |
1717 | set_bit(R5_LOCKED, &dev->flags); | |
1718 | if (!expand) | |
1719 | clear_bit(R5_UPTODATE, &dev->flags); | |
1720 | locked++; | |
1721 | } | |
1722 | } | |
8b3e6cdc DW |
1723 | if (locked + 1 == disks) |
1724 | if (!test_and_set_bit(STRIPE_FULL_WRITE, &sh->state)) | |
1725 | atomic_inc(&sh->raid_conf->pending_full_writes); | |
e33129d8 DW |
1726 | } else { |
1727 | BUG_ON(!(test_bit(R5_UPTODATE, &sh->dev[pd_idx].flags) || | |
1728 | test_bit(R5_Wantcompute, &sh->dev[pd_idx].flags))); | |
1729 | ||
1730 | set_bit(STRIPE_OP_PREXOR, &sh->ops.pending); | |
1731 | set_bit(STRIPE_OP_BIODRAIN, &sh->ops.pending); | |
1732 | set_bit(STRIPE_OP_POSTXOR, &sh->ops.pending); | |
1733 | ||
1734 | sh->ops.count += 3; | |
1735 | ||
1736 | for (i = disks; i--; ) { | |
1737 | struct r5dev *dev = &sh->dev[i]; | |
1738 | if (i == pd_idx) | |
1739 | continue; | |
1740 | ||
1741 | /* For a read-modify write there may be blocks that are | |
1742 | * locked for reading while others are ready to be | |
1743 | * written so we distinguish these blocks by the | |
1744 | * R5_Wantprexor bit | |
1745 | */ | |
1746 | if (dev->towrite && | |
1747 | (test_bit(R5_UPTODATE, &dev->flags) || | |
1748 | test_bit(R5_Wantcompute, &dev->flags))) { | |
1749 | set_bit(R5_Wantprexor, &dev->flags); | |
1750 | set_bit(R5_LOCKED, &dev->flags); | |
1751 | clear_bit(R5_UPTODATE, &dev->flags); | |
1752 | locked++; | |
1753 | } | |
1754 | } | |
1755 | } | |
1756 | ||
1757 | /* keep the parity disk locked while asynchronous operations | |
1758 | * are in flight | |
1759 | */ | |
1760 | set_bit(R5_LOCKED, &sh->dev[pd_idx].flags); | |
1761 | clear_bit(R5_UPTODATE, &sh->dev[pd_idx].flags); | |
1762 | locked++; | |
1763 | ||
1764 | pr_debug("%s: stripe %llu locked: %d pending: %lx\n", | |
e46b272b | 1765 | __func__, (unsigned long long)sh->sector, |
e33129d8 DW |
1766 | locked, sh->ops.pending); |
1767 | ||
1768 | return locked; | |
1769 | } | |
16a53ecc | 1770 | |
1da177e4 LT |
1771 | /* |
1772 | * Each stripe/dev can have one or more bion attached. | |
16a53ecc | 1773 | * toread/towrite point to the first in a chain. |
1da177e4 LT |
1774 | * The bi_next chain must be in order. |
1775 | */ | |
1776 | static int add_stripe_bio(struct stripe_head *sh, struct bio *bi, int dd_idx, int forwrite) | |
1777 | { | |
1778 | struct bio **bip; | |
1779 | raid5_conf_t *conf = sh->raid_conf; | |
72626685 | 1780 | int firstwrite=0; |
1da177e4 | 1781 | |
45b4233c | 1782 | pr_debug("adding bh b#%llu to stripe s#%llu\n", |
1da177e4 LT |
1783 | (unsigned long long)bi->bi_sector, |
1784 | (unsigned long long)sh->sector); | |
1785 | ||
1786 | ||
1787 | spin_lock(&sh->lock); | |
1788 | spin_lock_irq(&conf->device_lock); | |
72626685 | 1789 | if (forwrite) { |
1da177e4 | 1790 | bip = &sh->dev[dd_idx].towrite; |
72626685 N |
1791 | if (*bip == NULL && sh->dev[dd_idx].written == NULL) |
1792 | firstwrite = 1; | |
1793 | } else | |
1da177e4 LT |
1794 | bip = &sh->dev[dd_idx].toread; |
1795 | while (*bip && (*bip)->bi_sector < bi->bi_sector) { | |
1796 | if ((*bip)->bi_sector + ((*bip)->bi_size >> 9) > bi->bi_sector) | |
1797 | goto overlap; | |
1798 | bip = & (*bip)->bi_next; | |
1799 | } | |
1800 | if (*bip && (*bip)->bi_sector < bi->bi_sector + ((bi->bi_size)>>9)) | |
1801 | goto overlap; | |
1802 | ||
78bafebd | 1803 | BUG_ON(*bip && bi->bi_next && (*bip) != bi->bi_next); |
1da177e4 LT |
1804 | if (*bip) |
1805 | bi->bi_next = *bip; | |
1806 | *bip = bi; | |
1807 | bi->bi_phys_segments ++; | |
1808 | spin_unlock_irq(&conf->device_lock); | |
1809 | spin_unlock(&sh->lock); | |
1810 | ||
45b4233c | 1811 | pr_debug("added bi b#%llu to stripe s#%llu, disk %d.\n", |
1da177e4 LT |
1812 | (unsigned long long)bi->bi_sector, |
1813 | (unsigned long long)sh->sector, dd_idx); | |
1814 | ||
72626685 | 1815 | if (conf->mddev->bitmap && firstwrite) { |
72626685 N |
1816 | bitmap_startwrite(conf->mddev->bitmap, sh->sector, |
1817 | STRIPE_SECTORS, 0); | |
ae3c20cc | 1818 | sh->bm_seq = conf->seq_flush+1; |
72626685 N |
1819 | set_bit(STRIPE_BIT_DELAY, &sh->state); |
1820 | } | |
1821 | ||
1da177e4 LT |
1822 | if (forwrite) { |
1823 | /* check if page is covered */ | |
1824 | sector_t sector = sh->dev[dd_idx].sector; | |
1825 | for (bi=sh->dev[dd_idx].towrite; | |
1826 | sector < sh->dev[dd_idx].sector + STRIPE_SECTORS && | |
1827 | bi && bi->bi_sector <= sector; | |
1828 | bi = r5_next_bio(bi, sh->dev[dd_idx].sector)) { | |
1829 | if (bi->bi_sector + (bi->bi_size>>9) >= sector) | |
1830 | sector = bi->bi_sector + (bi->bi_size>>9); | |
1831 | } | |
1832 | if (sector >= sh->dev[dd_idx].sector + STRIPE_SECTORS) | |
1833 | set_bit(R5_OVERWRITE, &sh->dev[dd_idx].flags); | |
1834 | } | |
1835 | return 1; | |
1836 | ||
1837 | overlap: | |
1838 | set_bit(R5_Overlap, &sh->dev[dd_idx].flags); | |
1839 | spin_unlock_irq(&conf->device_lock); | |
1840 | spin_unlock(&sh->lock); | |
1841 | return 0; | |
1842 | } | |
1843 | ||
29269553 N |
1844 | static void end_reshape(raid5_conf_t *conf); |
1845 | ||
16a53ecc N |
1846 | static int page_is_zero(struct page *p) |
1847 | { | |
1848 | char *a = page_address(p); | |
1849 | return ((*(u32*)a) == 0 && | |
1850 | memcmp(a, a+4, STRIPE_SIZE-4)==0); | |
1851 | } | |
1852 | ||
ccfcc3c1 N |
1853 | static int stripe_to_pdidx(sector_t stripe, raid5_conf_t *conf, int disks) |
1854 | { | |
1855 | int sectors_per_chunk = conf->chunk_size >> 9; | |
ccfcc3c1 | 1856 | int pd_idx, dd_idx; |
2d2063ce CQH |
1857 | int chunk_offset = sector_div(stripe, sectors_per_chunk); |
1858 | ||
b875e531 N |
1859 | raid5_compute_sector(stripe * (disks - conf->max_degraded) |
1860 | *sectors_per_chunk + chunk_offset, | |
1861 | disks, disks - conf->max_degraded, | |
1862 | &dd_idx, &pd_idx, conf); | |
ccfcc3c1 N |
1863 | return pd_idx; |
1864 | } | |
1865 | ||
a4456856 DW |
1866 | static void |
1867 | handle_requests_to_failed_array(raid5_conf_t *conf, struct stripe_head *sh, | |
1868 | struct stripe_head_state *s, int disks, | |
1869 | struct bio **return_bi) | |
1870 | { | |
1871 | int i; | |
1872 | for (i = disks; i--; ) { | |
1873 | struct bio *bi; | |
1874 | int bitmap_end = 0; | |
1875 | ||
1876 | if (test_bit(R5_ReadError, &sh->dev[i].flags)) { | |
1877 | mdk_rdev_t *rdev; | |
1878 | rcu_read_lock(); | |
1879 | rdev = rcu_dereference(conf->disks[i].rdev); | |
1880 | if (rdev && test_bit(In_sync, &rdev->flags)) | |
1881 | /* multiple read failures in one stripe */ | |
1882 | md_error(conf->mddev, rdev); | |
1883 | rcu_read_unlock(); | |
1884 | } | |
1885 | spin_lock_irq(&conf->device_lock); | |
1886 | /* fail all writes first */ | |
1887 | bi = sh->dev[i].towrite; | |
1888 | sh->dev[i].towrite = NULL; | |
1889 | if (bi) { | |
1890 | s->to_write--; | |
1891 | bitmap_end = 1; | |
1892 | } | |
1893 | ||
1894 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) | |
1895 | wake_up(&conf->wait_for_overlap); | |
1896 | ||
1897 | while (bi && bi->bi_sector < | |
1898 | sh->dev[i].sector + STRIPE_SECTORS) { | |
1899 | struct bio *nextbi = r5_next_bio(bi, sh->dev[i].sector); | |
1900 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
1901 | if (--bi->bi_phys_segments == 0) { | |
1902 | md_write_end(conf->mddev); | |
1903 | bi->bi_next = *return_bi; | |
1904 | *return_bi = bi; | |
1905 | } | |
1906 | bi = nextbi; | |
1907 | } | |
1908 | /* and fail all 'written' */ | |
1909 | bi = sh->dev[i].written; | |
1910 | sh->dev[i].written = NULL; | |
1911 | if (bi) bitmap_end = 1; | |
1912 | while (bi && bi->bi_sector < | |
1913 | sh->dev[i].sector + STRIPE_SECTORS) { | |
1914 | struct bio *bi2 = r5_next_bio(bi, sh->dev[i].sector); | |
1915 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
1916 | if (--bi->bi_phys_segments == 0) { | |
1917 | md_write_end(conf->mddev); | |
1918 | bi->bi_next = *return_bi; | |
1919 | *return_bi = bi; | |
1920 | } | |
1921 | bi = bi2; | |
1922 | } | |
1923 | ||
b5e98d65 DW |
1924 | /* fail any reads if this device is non-operational and |
1925 | * the data has not reached the cache yet. | |
1926 | */ | |
1927 | if (!test_bit(R5_Wantfill, &sh->dev[i].flags) && | |
1928 | (!test_bit(R5_Insync, &sh->dev[i].flags) || | |
1929 | test_bit(R5_ReadError, &sh->dev[i].flags))) { | |
a4456856 DW |
1930 | bi = sh->dev[i].toread; |
1931 | sh->dev[i].toread = NULL; | |
1932 | if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags)) | |
1933 | wake_up(&conf->wait_for_overlap); | |
1934 | if (bi) s->to_read--; | |
1935 | while (bi && bi->bi_sector < | |
1936 | sh->dev[i].sector + STRIPE_SECTORS) { | |
1937 | struct bio *nextbi = | |
1938 | r5_next_bio(bi, sh->dev[i].sector); | |
1939 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
1940 | if (--bi->bi_phys_segments == 0) { | |
1941 | bi->bi_next = *return_bi; | |
1942 | *return_bi = bi; | |
1943 | } | |
1944 | bi = nextbi; | |
1945 | } | |
1946 | } | |
1947 | spin_unlock_irq(&conf->device_lock); | |
1948 | if (bitmap_end) | |
1949 | bitmap_endwrite(conf->mddev->bitmap, sh->sector, | |
1950 | STRIPE_SECTORS, 0, 0); | |
1951 | } | |
1952 | ||
8b3e6cdc DW |
1953 | if (test_and_clear_bit(STRIPE_FULL_WRITE, &sh->state)) |
1954 | if (atomic_dec_and_test(&conf->pending_full_writes)) | |
1955 | md_wakeup_thread(conf->mddev->thread); | |
a4456856 DW |
1956 | } |
1957 | ||
f38e1219 DW |
1958 | /* __handle_issuing_new_read_requests5 - returns 0 if there are no more disks |
1959 | * to process | |
1960 | */ | |
1961 | static int __handle_issuing_new_read_requests5(struct stripe_head *sh, | |
1962 | struct stripe_head_state *s, int disk_idx, int disks) | |
1963 | { | |
1964 | struct r5dev *dev = &sh->dev[disk_idx]; | |
1965 | struct r5dev *failed_dev = &sh->dev[s->failed_num]; | |
1966 | ||
1967 | /* don't schedule compute operations or reads on the parity block while | |
1968 | * a check is in flight | |
1969 | */ | |
1970 | if ((disk_idx == sh->pd_idx) && | |
1971 | test_bit(STRIPE_OP_CHECK, &sh->ops.pending)) | |
1972 | return ~0; | |
1973 | ||
1974 | /* is the data in this block needed, and can we get it? */ | |
1975 | if (!test_bit(R5_LOCKED, &dev->flags) && | |
1976 | !test_bit(R5_UPTODATE, &dev->flags) && (dev->toread || | |
1977 | (dev->towrite && !test_bit(R5_OVERWRITE, &dev->flags)) || | |
1978 | s->syncing || s->expanding || (s->failed && | |
1979 | (failed_dev->toread || (failed_dev->towrite && | |
1980 | !test_bit(R5_OVERWRITE, &failed_dev->flags) | |
1981 | ))))) { | |
1982 | /* 1/ We would like to get this block, possibly by computing it, | |
1983 | * but we might not be able to. | |
1984 | * | |
1985 | * 2/ Since parity check operations potentially make the parity | |
1986 | * block !uptodate it will need to be refreshed before any | |
1987 | * compute operations on data disks are scheduled. | |
1988 | * | |
1989 | * 3/ We hold off parity block re-reads until check operations | |
1990 | * have quiesced. | |
1991 | */ | |
1992 | if ((s->uptodate == disks - 1) && | |
c337869d | 1993 | (s->failed && disk_idx == s->failed_num) && |
f38e1219 DW |
1994 | !test_bit(STRIPE_OP_CHECK, &sh->ops.pending)) { |
1995 | set_bit(STRIPE_OP_COMPUTE_BLK, &sh->ops.pending); | |
1996 | set_bit(R5_Wantcompute, &dev->flags); | |
1997 | sh->ops.target = disk_idx; | |
1998 | s->req_compute = 1; | |
1999 | sh->ops.count++; | |
2000 | /* Careful: from this point on 'uptodate' is in the eye | |
2001 | * of raid5_run_ops which services 'compute' operations | |
2002 | * before writes. R5_Wantcompute flags a block that will | |
2003 | * be R5_UPTODATE by the time it is needed for a | |
2004 | * subsequent operation. | |
2005 | */ | |
2006 | s->uptodate++; | |
2007 | return 0; /* uptodate + compute == disks */ | |
2008 | } else if ((s->uptodate < disks - 1) && | |
2009 | test_bit(R5_Insync, &dev->flags)) { | |
2010 | /* Note: we hold off compute operations while checks are | |
2011 | * in flight, but we still prefer 'compute' over 'read' | |
2012 | * hence we only read if (uptodate < * disks-1) | |
2013 | */ | |
2014 | set_bit(R5_LOCKED, &dev->flags); | |
2015 | set_bit(R5_Wantread, &dev->flags); | |
2016 | if (!test_and_set_bit(STRIPE_OP_IO, &sh->ops.pending)) | |
2017 | sh->ops.count++; | |
2018 | s->locked++; | |
2019 | pr_debug("Reading block %d (sync=%d)\n", disk_idx, | |
2020 | s->syncing); | |
2021 | } | |
2022 | } | |
2023 | ||
2024 | return ~0; | |
2025 | } | |
2026 | ||
a4456856 DW |
2027 | static void handle_issuing_new_read_requests5(struct stripe_head *sh, |
2028 | struct stripe_head_state *s, int disks) | |
2029 | { | |
2030 | int i; | |
f38e1219 DW |
2031 | |
2032 | /* Clear completed compute operations. Parity recovery | |
2033 | * (STRIPE_OP_MOD_REPAIR_PD) implies a write-back which is handled | |
2034 | * later on in this routine | |
2035 | */ | |
2036 | if (test_bit(STRIPE_OP_COMPUTE_BLK, &sh->ops.complete) && | |
2037 | !test_bit(STRIPE_OP_MOD_REPAIR_PD, &sh->ops.pending)) { | |
2038 | clear_bit(STRIPE_OP_COMPUTE_BLK, &sh->ops.complete); | |
2039 | clear_bit(STRIPE_OP_COMPUTE_BLK, &sh->ops.ack); | |
2040 | clear_bit(STRIPE_OP_COMPUTE_BLK, &sh->ops.pending); | |
2041 | } | |
2042 | ||
2043 | /* look for blocks to read/compute, skip this if a compute | |
2044 | * is already in flight, or if the stripe contents are in the | |
2045 | * midst of changing due to a write | |
2046 | */ | |
2047 | if (!test_bit(STRIPE_OP_COMPUTE_BLK, &sh->ops.pending) && | |
2048 | !test_bit(STRIPE_OP_PREXOR, &sh->ops.pending) && | |
2049 | !test_bit(STRIPE_OP_POSTXOR, &sh->ops.pending)) { | |
2050 | for (i = disks; i--; ) | |
2051 | if (__handle_issuing_new_read_requests5( | |
2052 | sh, s, i, disks) == 0) | |
2053 | break; | |
a4456856 DW |
2054 | } |
2055 | set_bit(STRIPE_HANDLE, &sh->state); | |
2056 | } | |
2057 | ||
2058 | static void handle_issuing_new_read_requests6(struct stripe_head *sh, | |
2059 | struct stripe_head_state *s, struct r6_state *r6s, | |
2060 | int disks) | |
2061 | { | |
2062 | int i; | |
2063 | for (i = disks; i--; ) { | |
2064 | struct r5dev *dev = &sh->dev[i]; | |
2065 | if (!test_bit(R5_LOCKED, &dev->flags) && | |
2066 | !test_bit(R5_UPTODATE, &dev->flags) && | |
2067 | (dev->toread || (dev->towrite && | |
2068 | !test_bit(R5_OVERWRITE, &dev->flags)) || | |
2069 | s->syncing || s->expanding || | |
2070 | (s->failed >= 1 && | |
2071 | (sh->dev[r6s->failed_num[0]].toread || | |
2072 | s->to_write)) || | |
2073 | (s->failed >= 2 && | |
2074 | (sh->dev[r6s->failed_num[1]].toread || | |
2075 | s->to_write)))) { | |
2076 | /* we would like to get this block, possibly | |
2077 | * by computing it, but we might not be able to | |
2078 | */ | |
c337869d DW |
2079 | if ((s->uptodate == disks - 1) && |
2080 | (s->failed && (i == r6s->failed_num[0] || | |
2081 | i == r6s->failed_num[1]))) { | |
45b4233c | 2082 | pr_debug("Computing stripe %llu block %d\n", |
a4456856 DW |
2083 | (unsigned long long)sh->sector, i); |
2084 | compute_block_1(sh, i, 0); | |
2085 | s->uptodate++; | |
2086 | } else if ( s->uptodate == disks-2 && s->failed >= 2 ) { | |
2087 | /* Computing 2-failure is *very* expensive; only | |
2088 | * do it if failed >= 2 | |
2089 | */ | |
2090 | int other; | |
2091 | for (other = disks; other--; ) { | |
2092 | if (other == i) | |
2093 | continue; | |
2094 | if (!test_bit(R5_UPTODATE, | |
2095 | &sh->dev[other].flags)) | |
2096 | break; | |
2097 | } | |
2098 | BUG_ON(other < 0); | |
45b4233c | 2099 | pr_debug("Computing stripe %llu blocks %d,%d\n", |
a4456856 DW |
2100 | (unsigned long long)sh->sector, |
2101 | i, other); | |
2102 | compute_block_2(sh, i, other); | |
2103 | s->uptodate += 2; | |
2104 | } else if (test_bit(R5_Insync, &dev->flags)) { | |
2105 | set_bit(R5_LOCKED, &dev->flags); | |
2106 | set_bit(R5_Wantread, &dev->flags); | |
2107 | s->locked++; | |
45b4233c | 2108 | pr_debug("Reading block %d (sync=%d)\n", |
a4456856 DW |
2109 | i, s->syncing); |
2110 | } | |
2111 | } | |
2112 | } | |
2113 | set_bit(STRIPE_HANDLE, &sh->state); | |
2114 | } | |
2115 | ||
2116 | ||
2117 | /* handle_completed_write_requests | |
2118 | * any written block on an uptodate or failed drive can be returned. | |
2119 | * Note that if we 'wrote' to a failed drive, it will be UPTODATE, but | |
2120 | * never LOCKED, so we don't need to test 'failed' directly. | |
2121 | */ | |
2122 | static void handle_completed_write_requests(raid5_conf_t *conf, | |
2123 | struct stripe_head *sh, int disks, struct bio **return_bi) | |
2124 | { | |
2125 | int i; | |
2126 | struct r5dev *dev; | |
2127 | ||
2128 | for (i = disks; i--; ) | |
2129 | if (sh->dev[i].written) { | |
2130 | dev = &sh->dev[i]; | |
2131 | if (!test_bit(R5_LOCKED, &dev->flags) && | |
2132 | test_bit(R5_UPTODATE, &dev->flags)) { | |
2133 | /* We can return any write requests */ | |
2134 | struct bio *wbi, *wbi2; | |
2135 | int bitmap_end = 0; | |
45b4233c | 2136 | pr_debug("Return write for disc %d\n", i); |
a4456856 DW |
2137 | spin_lock_irq(&conf->device_lock); |
2138 | wbi = dev->written; | |
2139 | dev->written = NULL; | |
2140 | while (wbi && wbi->bi_sector < | |
2141 | dev->sector + STRIPE_SECTORS) { | |
2142 | wbi2 = r5_next_bio(wbi, dev->sector); | |
2143 | if (--wbi->bi_phys_segments == 0) { | |
2144 | md_write_end(conf->mddev); | |
2145 | wbi->bi_next = *return_bi; | |
2146 | *return_bi = wbi; | |
2147 | } | |
2148 | wbi = wbi2; | |
2149 | } | |
2150 | if (dev->towrite == NULL) | |
2151 | bitmap_end = 1; | |
2152 | spin_unlock_irq(&conf->device_lock); | |
2153 | if (bitmap_end) | |
2154 | bitmap_endwrite(conf->mddev->bitmap, | |
2155 | sh->sector, | |
2156 | STRIPE_SECTORS, | |
2157 | !test_bit(STRIPE_DEGRADED, &sh->state), | |
2158 | 0); | |
2159 | } | |
2160 | } | |
8b3e6cdc DW |
2161 | |
2162 | if (test_and_clear_bit(STRIPE_FULL_WRITE, &sh->state)) | |
2163 | if (atomic_dec_and_test(&conf->pending_full_writes)) | |
2164 | md_wakeup_thread(conf->mddev->thread); | |
a4456856 DW |
2165 | } |
2166 | ||
2167 | static void handle_issuing_new_write_requests5(raid5_conf_t *conf, | |
2168 | struct stripe_head *sh, struct stripe_head_state *s, int disks) | |
2169 | { | |
2170 | int rmw = 0, rcw = 0, i; | |
2171 | for (i = disks; i--; ) { | |
2172 | /* would I have to read this buffer for read_modify_write */ | |
2173 | struct r5dev *dev = &sh->dev[i]; | |
2174 | if ((dev->towrite || i == sh->pd_idx) && | |
2175 | !test_bit(R5_LOCKED, &dev->flags) && | |
f38e1219 DW |
2176 | !(test_bit(R5_UPTODATE, &dev->flags) || |
2177 | test_bit(R5_Wantcompute, &dev->flags))) { | |
a4456856 DW |
2178 | if (test_bit(R5_Insync, &dev->flags)) |
2179 | rmw++; | |
2180 | else | |
2181 | rmw += 2*disks; /* cannot read it */ | |
2182 | } | |
2183 | /* Would I have to read this buffer for reconstruct_write */ | |
2184 | if (!test_bit(R5_OVERWRITE, &dev->flags) && i != sh->pd_idx && | |
2185 | !test_bit(R5_LOCKED, &dev->flags) && | |
f38e1219 DW |
2186 | !(test_bit(R5_UPTODATE, &dev->flags) || |
2187 | test_bit(R5_Wantcompute, &dev->flags))) { | |
2188 | if (test_bit(R5_Insync, &dev->flags)) rcw++; | |
a4456856 DW |
2189 | else |
2190 | rcw += 2*disks; | |
2191 | } | |
2192 | } | |
45b4233c | 2193 | pr_debug("for sector %llu, rmw=%d rcw=%d\n", |
a4456856 DW |
2194 | (unsigned long long)sh->sector, rmw, rcw); |
2195 | set_bit(STRIPE_HANDLE, &sh->state); | |
2196 | if (rmw < rcw && rmw > 0) | |
2197 | /* prefer read-modify-write, but need to get some data */ | |
2198 | for (i = disks; i--; ) { | |
2199 | struct r5dev *dev = &sh->dev[i]; | |
2200 | if ((dev->towrite || i == sh->pd_idx) && | |
2201 | !test_bit(R5_LOCKED, &dev->flags) && | |
f38e1219 DW |
2202 | !(test_bit(R5_UPTODATE, &dev->flags) || |
2203 | test_bit(R5_Wantcompute, &dev->flags)) && | |
a4456856 DW |
2204 | test_bit(R5_Insync, &dev->flags)) { |
2205 | if ( | |
2206 | test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
45b4233c | 2207 | pr_debug("Read_old block " |
a4456856 DW |
2208 | "%d for r-m-w\n", i); |
2209 | set_bit(R5_LOCKED, &dev->flags); | |
2210 | set_bit(R5_Wantread, &dev->flags); | |
830ea016 DW |
2211 | if (!test_and_set_bit( |
2212 | STRIPE_OP_IO, &sh->ops.pending)) | |
2213 | sh->ops.count++; | |
a4456856 DW |
2214 | s->locked++; |
2215 | } else { | |
2216 | set_bit(STRIPE_DELAYED, &sh->state); | |
2217 | set_bit(STRIPE_HANDLE, &sh->state); | |
2218 | } | |
2219 | } | |
2220 | } | |
2221 | if (rcw <= rmw && rcw > 0) | |
2222 | /* want reconstruct write, but need to get some data */ | |
2223 | for (i = disks; i--; ) { | |
2224 | struct r5dev *dev = &sh->dev[i]; | |
2225 | if (!test_bit(R5_OVERWRITE, &dev->flags) && | |
2226 | i != sh->pd_idx && | |
2227 | !test_bit(R5_LOCKED, &dev->flags) && | |
f38e1219 DW |
2228 | !(test_bit(R5_UPTODATE, &dev->flags) || |
2229 | test_bit(R5_Wantcompute, &dev->flags)) && | |
a4456856 DW |
2230 | test_bit(R5_Insync, &dev->flags)) { |
2231 | if ( | |
2232 | test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
45b4233c | 2233 | pr_debug("Read_old block " |
a4456856 DW |
2234 | "%d for Reconstruct\n", i); |
2235 | set_bit(R5_LOCKED, &dev->flags); | |
2236 | set_bit(R5_Wantread, &dev->flags); | |
830ea016 DW |
2237 | if (!test_and_set_bit( |
2238 | STRIPE_OP_IO, &sh->ops.pending)) | |
2239 | sh->ops.count++; | |
a4456856 DW |
2240 | s->locked++; |
2241 | } else { | |
2242 | set_bit(STRIPE_DELAYED, &sh->state); | |
2243 | set_bit(STRIPE_HANDLE, &sh->state); | |
2244 | } | |
2245 | } | |
2246 | } | |
2247 | /* now if nothing is locked, and if we have enough data, | |
2248 | * we can start a write request | |
2249 | */ | |
f38e1219 DW |
2250 | /* since handle_stripe can be called at any time we need to handle the |
2251 | * case where a compute block operation has been submitted and then a | |
2252 | * subsequent call wants to start a write request. raid5_run_ops only | |
2253 | * handles the case where compute block and postxor are requested | |
2254 | * simultaneously. If this is not the case then new writes need to be | |
2255 | * held off until the compute completes. | |
2256 | */ | |
2257 | if ((s->req_compute || | |
2258 | !test_bit(STRIPE_OP_COMPUTE_BLK, &sh->ops.pending)) && | |
2259 | (s->locked == 0 && (rcw == 0 || rmw == 0) && | |
2260 | !test_bit(STRIPE_BIT_DELAY, &sh->state))) | |
e33129d8 | 2261 | s->locked += handle_write_operations5(sh, rcw == 0, 0); |
a4456856 DW |
2262 | } |
2263 | ||
2264 | static void handle_issuing_new_write_requests6(raid5_conf_t *conf, | |
2265 | struct stripe_head *sh, struct stripe_head_state *s, | |
2266 | struct r6_state *r6s, int disks) | |
2267 | { | |
2268 | int rcw = 0, must_compute = 0, pd_idx = sh->pd_idx, i; | |
2269 | int qd_idx = r6s->qd_idx; | |
2270 | for (i = disks; i--; ) { | |
2271 | struct r5dev *dev = &sh->dev[i]; | |
2272 | /* Would I have to read this buffer for reconstruct_write */ | |
2273 | if (!test_bit(R5_OVERWRITE, &dev->flags) | |
2274 | && i != pd_idx && i != qd_idx | |
2275 | && (!test_bit(R5_LOCKED, &dev->flags) | |
2276 | ) && | |
2277 | !test_bit(R5_UPTODATE, &dev->flags)) { | |
2278 | if (test_bit(R5_Insync, &dev->flags)) rcw++; | |
2279 | else { | |
45b4233c | 2280 | pr_debug("raid6: must_compute: " |
a4456856 DW |
2281 | "disk %d flags=%#lx\n", i, dev->flags); |
2282 | must_compute++; | |
2283 | } | |
2284 | } | |
2285 | } | |
45b4233c | 2286 | pr_debug("for sector %llu, rcw=%d, must_compute=%d\n", |
a4456856 DW |
2287 | (unsigned long long)sh->sector, rcw, must_compute); |
2288 | set_bit(STRIPE_HANDLE, &sh->state); | |
2289 | ||
2290 | if (rcw > 0) | |
2291 | /* want reconstruct write, but need to get some data */ | |
2292 | for (i = disks; i--; ) { | |
2293 | struct r5dev *dev = &sh->dev[i]; | |
2294 | if (!test_bit(R5_OVERWRITE, &dev->flags) | |
2295 | && !(s->failed == 0 && (i == pd_idx || i == qd_idx)) | |
2296 | && !test_bit(R5_LOCKED, &dev->flags) && | |
2297 | !test_bit(R5_UPTODATE, &dev->flags) && | |
2298 | test_bit(R5_Insync, &dev->flags)) { | |
2299 | if ( | |
2300 | test_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
45b4233c | 2301 | pr_debug("Read_old stripe %llu " |
a4456856 DW |
2302 | "block %d for Reconstruct\n", |
2303 | (unsigned long long)sh->sector, i); | |
2304 | set_bit(R5_LOCKED, &dev->flags); | |
2305 | set_bit(R5_Wantread, &dev->flags); | |
2306 | s->locked++; | |
2307 | } else { | |
45b4233c | 2308 | pr_debug("Request delayed stripe %llu " |
a4456856 DW |
2309 | "block %d for Reconstruct\n", |
2310 | (unsigned long long)sh->sector, i); | |
2311 | set_bit(STRIPE_DELAYED, &sh->state); | |
2312 | set_bit(STRIPE_HANDLE, &sh->state); | |
2313 | } | |
2314 | } | |
2315 | } | |
2316 | /* now if nothing is locked, and if we have enough data, we can start a | |
2317 | * write request | |
2318 | */ | |
2319 | if (s->locked == 0 && rcw == 0 && | |
2320 | !test_bit(STRIPE_BIT_DELAY, &sh->state)) { | |
2321 | if (must_compute > 0) { | |
2322 | /* We have failed blocks and need to compute them */ | |
2323 | switch (s->failed) { | |
2324 | case 0: | |
2325 | BUG(); | |
2326 | case 1: | |
2327 | compute_block_1(sh, r6s->failed_num[0], 0); | |
2328 | break; | |
2329 | case 2: | |
2330 | compute_block_2(sh, r6s->failed_num[0], | |
2331 | r6s->failed_num[1]); | |
2332 | break; | |
2333 | default: /* This request should have been failed? */ | |
2334 | BUG(); | |
2335 | } | |
2336 | } | |
2337 | ||
45b4233c | 2338 | pr_debug("Computing parity for stripe %llu\n", |
a4456856 DW |
2339 | (unsigned long long)sh->sector); |
2340 | compute_parity6(sh, RECONSTRUCT_WRITE); | |
2341 | /* now every locked buffer is ready to be written */ | |
2342 | for (i = disks; i--; ) | |
2343 | if (test_bit(R5_LOCKED, &sh->dev[i].flags)) { | |
45b4233c | 2344 | pr_debug("Writing stripe %llu block %d\n", |
a4456856 DW |
2345 | (unsigned long long)sh->sector, i); |
2346 | s->locked++; | |
2347 | set_bit(R5_Wantwrite, &sh->dev[i].flags); | |
2348 | } | |
8b3e6cdc DW |
2349 | if (s->locked == disks) |
2350 | if (!test_and_set_bit(STRIPE_FULL_WRITE, &sh->state)) | |
2351 | atomic_inc(&conf->pending_full_writes); | |
a4456856 DW |
2352 | /* after a RECONSTRUCT_WRITE, the stripe MUST be in-sync */ |
2353 | set_bit(STRIPE_INSYNC, &sh->state); | |
2354 | ||
2355 | if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
2356 | atomic_dec(&conf->preread_active_stripes); | |
2357 | if (atomic_read(&conf->preread_active_stripes) < | |
2358 | IO_THRESHOLD) | |
2359 | md_wakeup_thread(conf->mddev->thread); | |
2360 | } | |
2361 | } | |
2362 | } | |
2363 | ||
2364 | static void handle_parity_checks5(raid5_conf_t *conf, struct stripe_head *sh, | |
2365 | struct stripe_head_state *s, int disks) | |
2366 | { | |
bd2ab670 DW |
2367 | int canceled_check = 0; |
2368 | ||
a4456856 | 2369 | set_bit(STRIPE_HANDLE, &sh->state); |
e89f8962 | 2370 | |
bd2ab670 DW |
2371 | /* complete a check operation */ |
2372 | if (test_and_clear_bit(STRIPE_OP_CHECK, &sh->ops.complete)) { | |
c8894419 DW |
2373 | clear_bit(STRIPE_OP_CHECK, &sh->ops.ack); |
2374 | clear_bit(STRIPE_OP_CHECK, &sh->ops.pending); | |
bd2ab670 | 2375 | if (s->failed == 0) { |
e89f8962 DW |
2376 | if (sh->ops.zero_sum_result == 0) |
2377 | /* parity is correct (on disc, | |
2378 | * not in buffer any more) | |
2379 | */ | |
a4456856 DW |
2380 | set_bit(STRIPE_INSYNC, &sh->state); |
2381 | else { | |
e89f8962 DW |
2382 | conf->mddev->resync_mismatches += |
2383 | STRIPE_SECTORS; | |
2384 | if (test_bit( | |
2385 | MD_RECOVERY_CHECK, &conf->mddev->recovery)) | |
2386 | /* don't try to repair!! */ | |
2387 | set_bit(STRIPE_INSYNC, &sh->state); | |
2388 | else { | |
2389 | set_bit(STRIPE_OP_COMPUTE_BLK, | |
2390 | &sh->ops.pending); | |
2391 | set_bit(STRIPE_OP_MOD_REPAIR_PD, | |
2392 | &sh->ops.pending); | |
2393 | set_bit(R5_Wantcompute, | |
2394 | &sh->dev[sh->pd_idx].flags); | |
2395 | sh->ops.target = sh->pd_idx; | |
2396 | sh->ops.count++; | |
2397 | s->uptodate++; | |
2398 | } | |
a4456856 | 2399 | } |
bd2ab670 DW |
2400 | } else |
2401 | canceled_check = 1; /* STRIPE_INSYNC is not set */ | |
a4456856 | 2402 | } |
e89f8962 | 2403 | |
bd2ab670 DW |
2404 | /* start a new check operation if there are no failures, the stripe is |
2405 | * not insync, and a repair is not in flight | |
2406 | */ | |
2407 | if (s->failed == 0 && | |
2408 | !test_bit(STRIPE_INSYNC, &sh->state) && | |
2409 | !test_bit(STRIPE_OP_MOD_REPAIR_PD, &sh->ops.pending)) { | |
2410 | if (!test_and_set_bit(STRIPE_OP_CHECK, &sh->ops.pending)) { | |
2411 | BUG_ON(s->uptodate != disks); | |
2412 | clear_bit(R5_UPTODATE, &sh->dev[sh->pd_idx].flags); | |
2413 | sh->ops.count++; | |
2414 | s->uptodate--; | |
2415 | } | |
2416 | } | |
2417 | ||
c8894419 DW |
2418 | /* check if we can clear a parity disk reconstruct */ |
2419 | if (test_bit(STRIPE_OP_COMPUTE_BLK, &sh->ops.complete) && | |
2420 | test_bit(STRIPE_OP_MOD_REPAIR_PD, &sh->ops.pending)) { | |
2421 | ||
2422 | clear_bit(STRIPE_OP_MOD_REPAIR_PD, &sh->ops.pending); | |
2423 | clear_bit(STRIPE_OP_COMPUTE_BLK, &sh->ops.complete); | |
2424 | clear_bit(STRIPE_OP_COMPUTE_BLK, &sh->ops.ack); | |
2425 | clear_bit(STRIPE_OP_COMPUTE_BLK, &sh->ops.pending); | |
2426 | } | |
2427 | ||
2428 | ||
e89f8962 | 2429 | /* Wait for check parity and compute block operations to complete |
bd2ab670 DW |
2430 | * before write-back. If a failure occurred while the check operation |
2431 | * was in flight we need to cycle this stripe through handle_stripe | |
2432 | * since the parity block may not be uptodate | |
e89f8962 | 2433 | */ |
bd2ab670 DW |
2434 | if (!canceled_check && !test_bit(STRIPE_INSYNC, &sh->state) && |
2435 | !test_bit(STRIPE_OP_CHECK, &sh->ops.pending) && | |
2436 | !test_bit(STRIPE_OP_COMPUTE_BLK, &sh->ops.pending)) { | |
a4456856 DW |
2437 | struct r5dev *dev; |
2438 | /* either failed parity check, or recovery is happening */ | |
2439 | if (s->failed == 0) | |
2440 | s->failed_num = sh->pd_idx; | |
2441 | dev = &sh->dev[s->failed_num]; | |
2442 | BUG_ON(!test_bit(R5_UPTODATE, &dev->flags)); | |
2443 | BUG_ON(s->uptodate != disks); | |
2444 | ||
2445 | set_bit(R5_LOCKED, &dev->flags); | |
2446 | set_bit(R5_Wantwrite, &dev->flags); | |
830ea016 DW |
2447 | if (!test_and_set_bit(STRIPE_OP_IO, &sh->ops.pending)) |
2448 | sh->ops.count++; | |
2449 | ||
a4456856 DW |
2450 | clear_bit(STRIPE_DEGRADED, &sh->state); |
2451 | s->locked++; | |
2452 | set_bit(STRIPE_INSYNC, &sh->state); | |
2453 | } | |
2454 | } | |
2455 | ||
2456 | ||
2457 | static void handle_parity_checks6(raid5_conf_t *conf, struct stripe_head *sh, | |
2458 | struct stripe_head_state *s, | |
2459 | struct r6_state *r6s, struct page *tmp_page, | |
2460 | int disks) | |
2461 | { | |
2462 | int update_p = 0, update_q = 0; | |
2463 | struct r5dev *dev; | |
2464 | int pd_idx = sh->pd_idx; | |
2465 | int qd_idx = r6s->qd_idx; | |
2466 | ||
2467 | set_bit(STRIPE_HANDLE, &sh->state); | |
2468 | ||
2469 | BUG_ON(s->failed > 2); | |
2470 | BUG_ON(s->uptodate < disks); | |
2471 | /* Want to check and possibly repair P and Q. | |
2472 | * However there could be one 'failed' device, in which | |
2473 | * case we can only check one of them, possibly using the | |
2474 | * other to generate missing data | |
2475 | */ | |
2476 | ||
2477 | /* If !tmp_page, we cannot do the calculations, | |
2478 | * but as we have set STRIPE_HANDLE, we will soon be called | |
2479 | * by stripe_handle with a tmp_page - just wait until then. | |
2480 | */ | |
2481 | if (tmp_page) { | |
2482 | if (s->failed == r6s->q_failed) { | |
2483 | /* The only possible failed device holds 'Q', so it | |
2484 | * makes sense to check P (If anything else were failed, | |
2485 | * we would have used P to recreate it). | |
2486 | */ | |
2487 | compute_block_1(sh, pd_idx, 1); | |
2488 | if (!page_is_zero(sh->dev[pd_idx].page)) { | |
2489 | compute_block_1(sh, pd_idx, 0); | |
2490 | update_p = 1; | |
2491 | } | |
2492 | } | |
2493 | if (!r6s->q_failed && s->failed < 2) { | |
2494 | /* q is not failed, and we didn't use it to generate | |
2495 | * anything, so it makes sense to check it | |
2496 | */ | |
2497 | memcpy(page_address(tmp_page), | |
2498 | page_address(sh->dev[qd_idx].page), | |
2499 | STRIPE_SIZE); | |
2500 | compute_parity6(sh, UPDATE_PARITY); | |
2501 | if (memcmp(page_address(tmp_page), | |
2502 | page_address(sh->dev[qd_idx].page), | |
2503 | STRIPE_SIZE) != 0) { | |
2504 | clear_bit(STRIPE_INSYNC, &sh->state); | |
2505 | update_q = 1; | |
2506 | } | |
2507 | } | |
2508 | if (update_p || update_q) { | |
2509 | conf->mddev->resync_mismatches += STRIPE_SECTORS; | |
2510 | if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery)) | |
2511 | /* don't try to repair!! */ | |
2512 | update_p = update_q = 0; | |
2513 | } | |
2514 | ||
2515 | /* now write out any block on a failed drive, | |
2516 | * or P or Q if they need it | |
2517 | */ | |
2518 | ||
2519 | if (s->failed == 2) { | |
2520 | dev = &sh->dev[r6s->failed_num[1]]; | |
2521 | s->locked++; | |
2522 | set_bit(R5_LOCKED, &dev->flags); | |
2523 | set_bit(R5_Wantwrite, &dev->flags); | |
2524 | } | |
2525 | if (s->failed >= 1) { | |
2526 | dev = &sh->dev[r6s->failed_num[0]]; | |
2527 | s->locked++; | |
2528 | set_bit(R5_LOCKED, &dev->flags); | |
2529 | set_bit(R5_Wantwrite, &dev->flags); | |
2530 | } | |
2531 | ||
2532 | if (update_p) { | |
2533 | dev = &sh->dev[pd_idx]; | |
2534 | s->locked++; | |
2535 | set_bit(R5_LOCKED, &dev->flags); | |
2536 | set_bit(R5_Wantwrite, &dev->flags); | |
2537 | } | |
2538 | if (update_q) { | |
2539 | dev = &sh->dev[qd_idx]; | |
2540 | s->locked++; | |
2541 | set_bit(R5_LOCKED, &dev->flags); | |
2542 | set_bit(R5_Wantwrite, &dev->flags); | |
2543 | } | |
2544 | clear_bit(STRIPE_DEGRADED, &sh->state); | |
2545 | ||
2546 | set_bit(STRIPE_INSYNC, &sh->state); | |
2547 | } | |
2548 | } | |
2549 | ||
2550 | static void handle_stripe_expansion(raid5_conf_t *conf, struct stripe_head *sh, | |
2551 | struct r6_state *r6s) | |
2552 | { | |
2553 | int i; | |
2554 | ||
2555 | /* We have read all the blocks in this stripe and now we need to | |
2556 | * copy some of them into a target stripe for expand. | |
2557 | */ | |
f0a50d37 | 2558 | struct dma_async_tx_descriptor *tx = NULL; |
a4456856 DW |
2559 | clear_bit(STRIPE_EXPAND_SOURCE, &sh->state); |
2560 | for (i = 0; i < sh->disks; i++) | |
a2e08551 | 2561 | if (i != sh->pd_idx && (!r6s || i != r6s->qd_idx)) { |
a4456856 DW |
2562 | int dd_idx, pd_idx, j; |
2563 | struct stripe_head *sh2; | |
2564 | ||
2565 | sector_t bn = compute_blocknr(sh, i); | |
2566 | sector_t s = raid5_compute_sector(bn, conf->raid_disks, | |
2567 | conf->raid_disks - | |
2568 | conf->max_degraded, &dd_idx, | |
2569 | &pd_idx, conf); | |
2570 | sh2 = get_active_stripe(conf, s, conf->raid_disks, | |
2571 | pd_idx, 1); | |
2572 | if (sh2 == NULL) | |
2573 | /* so far only the early blocks of this stripe | |
2574 | * have been requested. When later blocks | |
2575 | * get requested, we will try again | |
2576 | */ | |
2577 | continue; | |
2578 | if (!test_bit(STRIPE_EXPANDING, &sh2->state) || | |
2579 | test_bit(R5_Expanded, &sh2->dev[dd_idx].flags)) { | |
2580 | /* must have already done this block */ | |
2581 | release_stripe(sh2); | |
2582 | continue; | |
2583 | } | |
f0a50d37 DW |
2584 | |
2585 | /* place all the copies on one channel */ | |
2586 | tx = async_memcpy(sh2->dev[dd_idx].page, | |
2587 | sh->dev[i].page, 0, 0, STRIPE_SIZE, | |
2588 | ASYNC_TX_DEP_ACK, tx, NULL, NULL); | |
2589 | ||
a4456856 DW |
2590 | set_bit(R5_Expanded, &sh2->dev[dd_idx].flags); |
2591 | set_bit(R5_UPTODATE, &sh2->dev[dd_idx].flags); | |
2592 | for (j = 0; j < conf->raid_disks; j++) | |
2593 | if (j != sh2->pd_idx && | |
a2e08551 N |
2594 | (!r6s || j != raid6_next_disk(sh2->pd_idx, |
2595 | sh2->disks)) && | |
a4456856 DW |
2596 | !test_bit(R5_Expanded, &sh2->dev[j].flags)) |
2597 | break; | |
2598 | if (j == conf->raid_disks) { | |
2599 | set_bit(STRIPE_EXPAND_READY, &sh2->state); | |
2600 | set_bit(STRIPE_HANDLE, &sh2->state); | |
2601 | } | |
2602 | release_stripe(sh2); | |
f0a50d37 | 2603 | |
a4456856 | 2604 | } |
a2e08551 N |
2605 | /* done submitting copies, wait for them to complete */ |
2606 | if (tx) { | |
2607 | async_tx_ack(tx); | |
2608 | dma_wait_for_async_tx(tx); | |
2609 | } | |
a4456856 | 2610 | } |
1da177e4 | 2611 | |
6bfe0b49 | 2612 | |
1da177e4 LT |
2613 | /* |
2614 | * handle_stripe - do things to a stripe. | |
2615 | * | |
2616 | * We lock the stripe and then examine the state of various bits | |
2617 | * to see what needs to be done. | |
2618 | * Possible results: | |
2619 | * return some read request which now have data | |
2620 | * return some write requests which are safely on disc | |
2621 | * schedule a read on some buffers | |
2622 | * schedule a write of some buffers | |
2623 | * return confirmation of parity correctness | |
2624 | * | |
1da177e4 LT |
2625 | * buffers are taken off read_list or write_list, and bh_cache buffers |
2626 | * get BH_Lock set before the stripe lock is released. | |
2627 | * | |
2628 | */ | |
a4456856 | 2629 | |
16a53ecc | 2630 | static void handle_stripe5(struct stripe_head *sh) |
1da177e4 LT |
2631 | { |
2632 | raid5_conf_t *conf = sh->raid_conf; | |
a4456856 DW |
2633 | int disks = sh->disks, i; |
2634 | struct bio *return_bi = NULL; | |
2635 | struct stripe_head_state s; | |
1da177e4 | 2636 | struct r5dev *dev; |
d84e0f10 | 2637 | unsigned long pending = 0; |
6bfe0b49 | 2638 | mdk_rdev_t *blocked_rdev = NULL; |
e0a115e5 | 2639 | int prexor; |
1da177e4 | 2640 | |
a4456856 | 2641 | memset(&s, 0, sizeof(s)); |
d84e0f10 DW |
2642 | pr_debug("handling stripe %llu, state=%#lx cnt=%d, pd_idx=%d " |
2643 | "ops=%lx:%lx:%lx\n", (unsigned long long)sh->sector, sh->state, | |
2644 | atomic_read(&sh->count), sh->pd_idx, | |
2645 | sh->ops.pending, sh->ops.ack, sh->ops.complete); | |
1da177e4 LT |
2646 | |
2647 | spin_lock(&sh->lock); | |
2648 | clear_bit(STRIPE_HANDLE, &sh->state); | |
2649 | clear_bit(STRIPE_DELAYED, &sh->state); | |
2650 | ||
a4456856 DW |
2651 | s.syncing = test_bit(STRIPE_SYNCING, &sh->state); |
2652 | s.expanding = test_bit(STRIPE_EXPAND_SOURCE, &sh->state); | |
2653 | s.expanded = test_bit(STRIPE_EXPAND_READY, &sh->state); | |
1da177e4 LT |
2654 | /* Now to look around and see what can be done */ |
2655 | ||
def6ae26 NB |
2656 | /* clean-up completed biofill operations */ |
2657 | if (test_bit(STRIPE_OP_BIOFILL, &sh->ops.complete)) { | |
2658 | clear_bit(STRIPE_OP_BIOFILL, &sh->ops.pending); | |
2659 | clear_bit(STRIPE_OP_BIOFILL, &sh->ops.ack); | |
2660 | clear_bit(STRIPE_OP_BIOFILL, &sh->ops.complete); | |
2661 | } | |
2662 | ||
9910f16a | 2663 | rcu_read_lock(); |
1da177e4 LT |
2664 | for (i=disks; i--; ) { |
2665 | mdk_rdev_t *rdev; | |
a4456856 | 2666 | struct r5dev *dev = &sh->dev[i]; |
1da177e4 | 2667 | clear_bit(R5_Insync, &dev->flags); |
1da177e4 | 2668 | |
b5e98d65 DW |
2669 | pr_debug("check %d: state 0x%lx toread %p read %p write %p " |
2670 | "written %p\n", i, dev->flags, dev->toread, dev->read, | |
2671 | dev->towrite, dev->written); | |
2672 | ||
2673 | /* maybe we can request a biofill operation | |
2674 | * | |
2675 | * new wantfill requests are only permitted while | |
2676 | * STRIPE_OP_BIOFILL is clear | |
2677 | */ | |
2678 | if (test_bit(R5_UPTODATE, &dev->flags) && dev->toread && | |
2679 | !test_bit(STRIPE_OP_BIOFILL, &sh->ops.pending)) | |
2680 | set_bit(R5_Wantfill, &dev->flags); | |
1da177e4 LT |
2681 | |
2682 | /* now count some things */ | |
a4456856 DW |
2683 | if (test_bit(R5_LOCKED, &dev->flags)) s.locked++; |
2684 | if (test_bit(R5_UPTODATE, &dev->flags)) s.uptodate++; | |
f38e1219 | 2685 | if (test_bit(R5_Wantcompute, &dev->flags)) s.compute++; |
1da177e4 | 2686 | |
b5e98d65 DW |
2687 | if (test_bit(R5_Wantfill, &dev->flags)) |
2688 | s.to_fill++; | |
2689 | else if (dev->toread) | |
a4456856 | 2690 | s.to_read++; |
1da177e4 | 2691 | if (dev->towrite) { |
a4456856 | 2692 | s.to_write++; |
1da177e4 | 2693 | if (!test_bit(R5_OVERWRITE, &dev->flags)) |
a4456856 | 2694 | s.non_overwrite++; |
1da177e4 | 2695 | } |
a4456856 DW |
2696 | if (dev->written) |
2697 | s.written++; | |
9910f16a | 2698 | rdev = rcu_dereference(conf->disks[i].rdev); |
6bfe0b49 DW |
2699 | if (rdev && unlikely(test_bit(Blocked, &rdev->flags))) { |
2700 | blocked_rdev = rdev; | |
2701 | atomic_inc(&rdev->nr_pending); | |
2702 | break; | |
2703 | } | |
b2d444d7 | 2704 | if (!rdev || !test_bit(In_sync, &rdev->flags)) { |
14f8d26b | 2705 | /* The ReadError flag will just be confusing now */ |
4e5314b5 N |
2706 | clear_bit(R5_ReadError, &dev->flags); |
2707 | clear_bit(R5_ReWrite, &dev->flags); | |
2708 | } | |
b2d444d7 | 2709 | if (!rdev || !test_bit(In_sync, &rdev->flags) |
4e5314b5 | 2710 | || test_bit(R5_ReadError, &dev->flags)) { |
a4456856 DW |
2711 | s.failed++; |
2712 | s.failed_num = i; | |
1da177e4 LT |
2713 | } else |
2714 | set_bit(R5_Insync, &dev->flags); | |
2715 | } | |
9910f16a | 2716 | rcu_read_unlock(); |
b5e98d65 | 2717 | |
6bfe0b49 DW |
2718 | if (unlikely(blocked_rdev)) { |
2719 | set_bit(STRIPE_HANDLE, &sh->state); | |
2720 | goto unlock; | |
2721 | } | |
2722 | ||
b5e98d65 DW |
2723 | if (s.to_fill && !test_and_set_bit(STRIPE_OP_BIOFILL, &sh->ops.pending)) |
2724 | sh->ops.count++; | |
2725 | ||
45b4233c | 2726 | pr_debug("locked=%d uptodate=%d to_read=%d" |
1da177e4 | 2727 | " to_write=%d failed=%d failed_num=%d\n", |
a4456856 DW |
2728 | s.locked, s.uptodate, s.to_read, s.to_write, |
2729 | s.failed, s.failed_num); | |
1da177e4 LT |
2730 | /* check if the array has lost two devices and, if so, some requests might |
2731 | * need to be failed | |
2732 | */ | |
a4456856 DW |
2733 | if (s.failed > 1 && s.to_read+s.to_write+s.written) |
2734 | handle_requests_to_failed_array(conf, sh, &s, disks, | |
2735 | &return_bi); | |
2736 | if (s.failed > 1 && s.syncing) { | |
1da177e4 LT |
2737 | md_done_sync(conf->mddev, STRIPE_SECTORS,0); |
2738 | clear_bit(STRIPE_SYNCING, &sh->state); | |
a4456856 | 2739 | s.syncing = 0; |
1da177e4 LT |
2740 | } |
2741 | ||
2742 | /* might be able to return some write requests if the parity block | |
2743 | * is safe, or on a failed drive | |
2744 | */ | |
2745 | dev = &sh->dev[sh->pd_idx]; | |
a4456856 DW |
2746 | if ( s.written && |
2747 | ((test_bit(R5_Insync, &dev->flags) && | |
2748 | !test_bit(R5_LOCKED, &dev->flags) && | |
2749 | test_bit(R5_UPTODATE, &dev->flags)) || | |
2750 | (s.failed == 1 && s.failed_num == sh->pd_idx))) | |
2751 | handle_completed_write_requests(conf, sh, disks, &return_bi); | |
1da177e4 LT |
2752 | |
2753 | /* Now we might consider reading some blocks, either to check/generate | |
2754 | * parity, or to satisfy requests | |
2755 | * or to load a block that is being partially written. | |
2756 | */ | |
a4456856 | 2757 | if (s.to_read || s.non_overwrite || |
f38e1219 DW |
2758 | (s.syncing && (s.uptodate + s.compute < disks)) || s.expanding || |
2759 | test_bit(STRIPE_OP_COMPUTE_BLK, &sh->ops.pending)) | |
a4456856 | 2760 | handle_issuing_new_read_requests5(sh, &s, disks); |
1da177e4 | 2761 | |
e33129d8 DW |
2762 | /* Now we check to see if any write operations have recently |
2763 | * completed | |
2764 | */ | |
2765 | ||
2766 | /* leave prexor set until postxor is done, allows us to distinguish | |
2767 | * a rmw from a rcw during biodrain | |
2768 | */ | |
e0a115e5 | 2769 | prexor = 0; |
e33129d8 DW |
2770 | if (test_bit(STRIPE_OP_PREXOR, &sh->ops.complete) && |
2771 | test_bit(STRIPE_OP_POSTXOR, &sh->ops.complete)) { | |
2772 | ||
e0a115e5 | 2773 | prexor = 1; |
e33129d8 DW |
2774 | clear_bit(STRIPE_OP_PREXOR, &sh->ops.complete); |
2775 | clear_bit(STRIPE_OP_PREXOR, &sh->ops.ack); | |
2776 | clear_bit(STRIPE_OP_PREXOR, &sh->ops.pending); | |
2777 | ||
2778 | for (i = disks; i--; ) | |
2779 | clear_bit(R5_Wantprexor, &sh->dev[i].flags); | |
2780 | } | |
2781 | ||
2782 | /* if only POSTXOR is set then this is an 'expand' postxor */ | |
2783 | if (test_bit(STRIPE_OP_BIODRAIN, &sh->ops.complete) && | |
2784 | test_bit(STRIPE_OP_POSTXOR, &sh->ops.complete)) { | |
2785 | ||
2786 | clear_bit(STRIPE_OP_BIODRAIN, &sh->ops.complete); | |
2787 | clear_bit(STRIPE_OP_BIODRAIN, &sh->ops.ack); | |
2788 | clear_bit(STRIPE_OP_BIODRAIN, &sh->ops.pending); | |
2789 | ||
2790 | clear_bit(STRIPE_OP_POSTXOR, &sh->ops.complete); | |
2791 | clear_bit(STRIPE_OP_POSTXOR, &sh->ops.ack); | |
2792 | clear_bit(STRIPE_OP_POSTXOR, &sh->ops.pending); | |
2793 | ||
2794 | /* All the 'written' buffers and the parity block are ready to | |
2795 | * be written back to disk | |
2796 | */ | |
2797 | BUG_ON(!test_bit(R5_UPTODATE, &sh->dev[sh->pd_idx].flags)); | |
2798 | for (i = disks; i--; ) { | |
2799 | dev = &sh->dev[i]; | |
2800 | if (test_bit(R5_LOCKED, &dev->flags) && | |
2801 | (i == sh->pd_idx || dev->written)) { | |
2802 | pr_debug("Writing block %d\n", i); | |
2803 | set_bit(R5_Wantwrite, &dev->flags); | |
2804 | if (!test_and_set_bit( | |
2805 | STRIPE_OP_IO, &sh->ops.pending)) | |
2806 | sh->ops.count++; | |
e0a115e5 DW |
2807 | if (prexor) |
2808 | continue; | |
e33129d8 DW |
2809 | if (!test_bit(R5_Insync, &dev->flags) || |
2810 | (i == sh->pd_idx && s.failed == 0)) | |
2811 | set_bit(STRIPE_INSYNC, &sh->state); | |
2812 | } | |
2813 | } | |
2814 | if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) { | |
2815 | atomic_dec(&conf->preread_active_stripes); | |
2816 | if (atomic_read(&conf->preread_active_stripes) < | |
2817 | IO_THRESHOLD) | |
2818 | md_wakeup_thread(conf->mddev->thread); | |
2819 | } | |
2820 | } | |
2821 | ||
2822 | /* Now to consider new write requests and what else, if anything | |
2823 | * should be read. We do not handle new writes when: | |
2824 | * 1/ A 'write' operation (copy+xor) is already in flight. | |
2825 | * 2/ A 'check' operation is in flight, as it may clobber the parity | |
2826 | * block. | |
2827 | */ | |
2828 | if (s.to_write && !test_bit(STRIPE_OP_POSTXOR, &sh->ops.pending) && | |
2829 | !test_bit(STRIPE_OP_CHECK, &sh->ops.pending)) | |
a4456856 | 2830 | handle_issuing_new_write_requests5(conf, sh, &s, disks); |
1da177e4 LT |
2831 | |
2832 | /* maybe we need to check and possibly fix the parity for this stripe | |
e89f8962 DW |
2833 | * Any reads will already have been scheduled, so we just see if enough |
2834 | * data is available. The parity check is held off while parity | |
2835 | * dependent operations are in flight. | |
1da177e4 | 2836 | */ |
e89f8962 DW |
2837 | if ((s.syncing && s.locked == 0 && |
2838 | !test_bit(STRIPE_OP_COMPUTE_BLK, &sh->ops.pending) && | |
2839 | !test_bit(STRIPE_INSYNC, &sh->state)) || | |
2840 | test_bit(STRIPE_OP_CHECK, &sh->ops.pending) || | |
2841 | test_bit(STRIPE_OP_MOD_REPAIR_PD, &sh->ops.pending)) | |
a4456856 | 2842 | handle_parity_checks5(conf, sh, &s, disks); |
e89f8962 | 2843 | |
a4456856 | 2844 | if (s.syncing && s.locked == 0 && test_bit(STRIPE_INSYNC, &sh->state)) { |
1da177e4 LT |
2845 | md_done_sync(conf->mddev, STRIPE_SECTORS,1); |
2846 | clear_bit(STRIPE_SYNCING, &sh->state); | |
2847 | } | |
4e5314b5 N |
2848 | |
2849 | /* If the failed drive is just a ReadError, then we might need to progress | |
2850 | * the repair/check process | |
2851 | */ | |
a4456856 DW |
2852 | if (s.failed == 1 && !conf->mddev->ro && |
2853 | test_bit(R5_ReadError, &sh->dev[s.failed_num].flags) | |
2854 | && !test_bit(R5_LOCKED, &sh->dev[s.failed_num].flags) | |
2855 | && test_bit(R5_UPTODATE, &sh->dev[s.failed_num].flags) | |
4e5314b5 | 2856 | ) { |
a4456856 | 2857 | dev = &sh->dev[s.failed_num]; |
4e5314b5 N |
2858 | if (!test_bit(R5_ReWrite, &dev->flags)) { |
2859 | set_bit(R5_Wantwrite, &dev->flags); | |
830ea016 DW |
2860 | if (!test_and_set_bit(STRIPE_OP_IO, &sh->ops.pending)) |
2861 | sh->ops.count++; | |
4e5314b5 N |
2862 | set_bit(R5_ReWrite, &dev->flags); |
2863 | set_bit(R5_LOCKED, &dev->flags); | |
a4456856 | 2864 | s.locked++; |
4e5314b5 N |
2865 | } else { |
2866 | /* let's read it back */ | |
2867 | set_bit(R5_Wantread, &dev->flags); | |
830ea016 DW |
2868 | if (!test_and_set_bit(STRIPE_OP_IO, &sh->ops.pending)) |
2869 | sh->ops.count++; | |
4e5314b5 | 2870 | set_bit(R5_LOCKED, &dev->flags); |
a4456856 | 2871 | s.locked++; |
4e5314b5 N |
2872 | } |
2873 | } | |
2874 | ||
f0a50d37 DW |
2875 | /* Finish postxor operations initiated by the expansion |
2876 | * process | |
2877 | */ | |
2878 | if (test_bit(STRIPE_OP_POSTXOR, &sh->ops.complete) && | |
2879 | !test_bit(STRIPE_OP_BIODRAIN, &sh->ops.pending)) { | |
2880 | ||
2881 | clear_bit(STRIPE_EXPANDING, &sh->state); | |
2882 | ||
2883 | clear_bit(STRIPE_OP_POSTXOR, &sh->ops.pending); | |
2884 | clear_bit(STRIPE_OP_POSTXOR, &sh->ops.ack); | |
2885 | clear_bit(STRIPE_OP_POSTXOR, &sh->ops.complete); | |
2886 | ||
a4456856 | 2887 | for (i = conf->raid_disks; i--; ) { |
ccfcc3c1 | 2888 | set_bit(R5_Wantwrite, &sh->dev[i].flags); |
efe31143 NB |
2889 | set_bit(R5_LOCKED, &dev->flags); |
2890 | s.locked++; | |
f0a50d37 DW |
2891 | if (!test_and_set_bit(STRIPE_OP_IO, &sh->ops.pending)) |
2892 | sh->ops.count++; | |
ccfcc3c1 | 2893 | } |
f0a50d37 DW |
2894 | } |
2895 | ||
2896 | if (s.expanded && test_bit(STRIPE_EXPANDING, &sh->state) && | |
2897 | !test_bit(STRIPE_OP_POSTXOR, &sh->ops.pending)) { | |
2898 | /* Need to write out all blocks after computing parity */ | |
2899 | sh->disks = conf->raid_disks; | |
2900 | sh->pd_idx = stripe_to_pdidx(sh->sector, conf, | |
2901 | conf->raid_disks); | |
a2e08551 | 2902 | s.locked += handle_write_operations5(sh, 1, 1); |
f0a50d37 | 2903 | } else if (s.expanded && |
efe31143 | 2904 | s.locked == 0 && |
f0a50d37 | 2905 | !test_bit(STRIPE_OP_POSTXOR, &sh->ops.pending)) { |
ccfcc3c1 | 2906 | clear_bit(STRIPE_EXPAND_READY, &sh->state); |
f6705578 | 2907 | atomic_dec(&conf->reshape_stripes); |
ccfcc3c1 N |
2908 | wake_up(&conf->wait_for_overlap); |
2909 | md_done_sync(conf->mddev, STRIPE_SECTORS, 1); | |
2910 | } | |
2911 | ||
0f94e87c DW |
2912 | if (s.expanding && s.locked == 0 && |
2913 | !test_bit(STRIPE_OP_COMPUTE_BLK, &sh->ops.pending)) | |
a4456856 | 2914 | handle_stripe_expansion(conf, sh, NULL); |
ccfcc3c1 | 2915 | |
d84e0f10 DW |
2916 | if (sh->ops.count) |
2917 | pending = get_stripe_work(sh); | |
2918 | ||
6bfe0b49 | 2919 | unlock: |
1da177e4 LT |
2920 | spin_unlock(&sh->lock); |
2921 | ||
6bfe0b49 DW |
2922 | /* wait for this device to become unblocked */ |
2923 | if (unlikely(blocked_rdev)) | |
2924 | md_wait_for_blocked_rdev(blocked_rdev, conf->mddev); | |
2925 | ||
d84e0f10 DW |
2926 | if (pending) |
2927 | raid5_run_ops(sh, pending); | |
2928 | ||
a4456856 | 2929 | return_io(return_bi); |
1da177e4 | 2930 | |
1da177e4 LT |
2931 | } |
2932 | ||
16a53ecc | 2933 | static void handle_stripe6(struct stripe_head *sh, struct page *tmp_page) |
1da177e4 | 2934 | { |
16a53ecc | 2935 | raid6_conf_t *conf = sh->raid_conf; |
f416885e | 2936 | int disks = sh->disks; |
a4456856 DW |
2937 | struct bio *return_bi = NULL; |
2938 | int i, pd_idx = sh->pd_idx; | |
2939 | struct stripe_head_state s; | |
2940 | struct r6_state r6s; | |
16a53ecc | 2941 | struct r5dev *dev, *pdev, *qdev; |
6bfe0b49 | 2942 | mdk_rdev_t *blocked_rdev = NULL; |
1da177e4 | 2943 | |
a4456856 | 2944 | r6s.qd_idx = raid6_next_disk(pd_idx, disks); |
45b4233c | 2945 | pr_debug("handling stripe %llu, state=%#lx cnt=%d, " |
a4456856 DW |
2946 | "pd_idx=%d, qd_idx=%d\n", |
2947 | (unsigned long long)sh->sector, sh->state, | |
2948 | atomic_read(&sh->count), pd_idx, r6s.qd_idx); | |
2949 | memset(&s, 0, sizeof(s)); | |
72626685 | 2950 | |
16a53ecc N |
2951 | spin_lock(&sh->lock); |
2952 | clear_bit(STRIPE_HANDLE, &sh->state); | |
2953 | clear_bit(STRIPE_DELAYED, &sh->state); | |
2954 | ||
a4456856 DW |
2955 | s.syncing = test_bit(STRIPE_SYNCING, &sh->state); |
2956 | s.expanding = test_bit(STRIPE_EXPAND_SOURCE, &sh->state); | |
2957 | s.expanded = test_bit(STRIPE_EXPAND_READY, &sh->state); | |
16a53ecc | 2958 | /* Now to look around and see what can be done */ |
1da177e4 LT |
2959 | |
2960 | rcu_read_lock(); | |
16a53ecc N |
2961 | for (i=disks; i--; ) { |
2962 | mdk_rdev_t *rdev; | |
2963 | dev = &sh->dev[i]; | |
2964 | clear_bit(R5_Insync, &dev->flags); | |
1da177e4 | 2965 | |
45b4233c | 2966 | pr_debug("check %d: state 0x%lx read %p write %p written %p\n", |
16a53ecc N |
2967 | i, dev->flags, dev->toread, dev->towrite, dev->written); |
2968 | /* maybe we can reply to a read */ | |
2969 | if (test_bit(R5_UPTODATE, &dev->flags) && dev->toread) { | |
2970 | struct bio *rbi, *rbi2; | |
45b4233c | 2971 | pr_debug("Return read for disc %d\n", i); |
16a53ecc N |
2972 | spin_lock_irq(&conf->device_lock); |
2973 | rbi = dev->toread; | |
2974 | dev->toread = NULL; | |
2975 | if (test_and_clear_bit(R5_Overlap, &dev->flags)) | |
2976 | wake_up(&conf->wait_for_overlap); | |
2977 | spin_unlock_irq(&conf->device_lock); | |
2978 | while (rbi && rbi->bi_sector < dev->sector + STRIPE_SECTORS) { | |
2979 | copy_data(0, rbi, dev->page, dev->sector); | |
2980 | rbi2 = r5_next_bio(rbi, dev->sector); | |
2981 | spin_lock_irq(&conf->device_lock); | |
2982 | if (--rbi->bi_phys_segments == 0) { | |
2983 | rbi->bi_next = return_bi; | |
2984 | return_bi = rbi; | |
2985 | } | |
2986 | spin_unlock_irq(&conf->device_lock); | |
2987 | rbi = rbi2; | |
2988 | } | |
2989 | } | |
1da177e4 | 2990 | |
16a53ecc | 2991 | /* now count some things */ |
a4456856 DW |
2992 | if (test_bit(R5_LOCKED, &dev->flags)) s.locked++; |
2993 | if (test_bit(R5_UPTODATE, &dev->flags)) s.uptodate++; | |
1da177e4 | 2994 | |
16a53ecc | 2995 | |
a4456856 DW |
2996 | if (dev->toread) |
2997 | s.to_read++; | |
16a53ecc | 2998 | if (dev->towrite) { |
a4456856 | 2999 | s.to_write++; |
16a53ecc | 3000 | if (!test_bit(R5_OVERWRITE, &dev->flags)) |
a4456856 | 3001 | s.non_overwrite++; |
16a53ecc | 3002 | } |
a4456856 DW |
3003 | if (dev->written) |
3004 | s.written++; | |
16a53ecc | 3005 | rdev = rcu_dereference(conf->disks[i].rdev); |
6bfe0b49 DW |
3006 | if (rdev && unlikely(test_bit(Blocked, &rdev->flags))) { |
3007 | blocked_rdev = rdev; | |
3008 | atomic_inc(&rdev->nr_pending); | |
3009 | break; | |
3010 | } | |
16a53ecc N |
3011 | if (!rdev || !test_bit(In_sync, &rdev->flags)) { |
3012 | /* The ReadError flag will just be confusing now */ | |
3013 | clear_bit(R5_ReadError, &dev->flags); | |
3014 | clear_bit(R5_ReWrite, &dev->flags); | |
1da177e4 | 3015 | } |
16a53ecc N |
3016 | if (!rdev || !test_bit(In_sync, &rdev->flags) |
3017 | || test_bit(R5_ReadError, &dev->flags)) { | |
a4456856 DW |
3018 | if (s.failed < 2) |
3019 | r6s.failed_num[s.failed] = i; | |
3020 | s.failed++; | |
16a53ecc N |
3021 | } else |
3022 | set_bit(R5_Insync, &dev->flags); | |
1da177e4 LT |
3023 | } |
3024 | rcu_read_unlock(); | |
6bfe0b49 DW |
3025 | |
3026 | if (unlikely(blocked_rdev)) { | |
3027 | set_bit(STRIPE_HANDLE, &sh->state); | |
3028 | goto unlock; | |
3029 | } | |
45b4233c | 3030 | pr_debug("locked=%d uptodate=%d to_read=%d" |
16a53ecc | 3031 | " to_write=%d failed=%d failed_num=%d,%d\n", |
a4456856 DW |
3032 | s.locked, s.uptodate, s.to_read, s.to_write, s.failed, |
3033 | r6s.failed_num[0], r6s.failed_num[1]); | |
3034 | /* check if the array has lost >2 devices and, if so, some requests | |
3035 | * might need to be failed | |
16a53ecc | 3036 | */ |
a4456856 DW |
3037 | if (s.failed > 2 && s.to_read+s.to_write+s.written) |
3038 | handle_requests_to_failed_array(conf, sh, &s, disks, | |
3039 | &return_bi); | |
3040 | if (s.failed > 2 && s.syncing) { | |
16a53ecc N |
3041 | md_done_sync(conf->mddev, STRIPE_SECTORS,0); |
3042 | clear_bit(STRIPE_SYNCING, &sh->state); | |
a4456856 | 3043 | s.syncing = 0; |
16a53ecc N |
3044 | } |
3045 | ||
3046 | /* | |
3047 | * might be able to return some write requests if the parity blocks | |
3048 | * are safe, or on a failed drive | |
3049 | */ | |
3050 | pdev = &sh->dev[pd_idx]; | |
a4456856 DW |
3051 | r6s.p_failed = (s.failed >= 1 && r6s.failed_num[0] == pd_idx) |
3052 | || (s.failed >= 2 && r6s.failed_num[1] == pd_idx); | |
3053 | qdev = &sh->dev[r6s.qd_idx]; | |
3054 | r6s.q_failed = (s.failed >= 1 && r6s.failed_num[0] == r6s.qd_idx) | |
3055 | || (s.failed >= 2 && r6s.failed_num[1] == r6s.qd_idx); | |
3056 | ||
3057 | if ( s.written && | |
3058 | ( r6s.p_failed || ((test_bit(R5_Insync, &pdev->flags) | |
16a53ecc | 3059 | && !test_bit(R5_LOCKED, &pdev->flags) |
a4456856 DW |
3060 | && test_bit(R5_UPTODATE, &pdev->flags)))) && |
3061 | ( r6s.q_failed || ((test_bit(R5_Insync, &qdev->flags) | |
16a53ecc | 3062 | && !test_bit(R5_LOCKED, &qdev->flags) |
a4456856 DW |
3063 | && test_bit(R5_UPTODATE, &qdev->flags))))) |
3064 | handle_completed_write_requests(conf, sh, disks, &return_bi); | |
16a53ecc N |
3065 | |
3066 | /* Now we might consider reading some blocks, either to check/generate | |
3067 | * parity, or to satisfy requests | |
3068 | * or to load a block that is being partially written. | |
3069 | */ | |
a4456856 DW |
3070 | if (s.to_read || s.non_overwrite || (s.to_write && s.failed) || |
3071 | (s.syncing && (s.uptodate < disks)) || s.expanding) | |
3072 | handle_issuing_new_read_requests6(sh, &s, &r6s, disks); | |
16a53ecc N |
3073 | |
3074 | /* now to consider writing and what else, if anything should be read */ | |
a4456856 DW |
3075 | if (s.to_write) |
3076 | handle_issuing_new_write_requests6(conf, sh, &s, &r6s, disks); | |
16a53ecc N |
3077 | |
3078 | /* maybe we need to check and possibly fix the parity for this stripe | |
a4456856 DW |
3079 | * Any reads will already have been scheduled, so we just see if enough |
3080 | * data is available | |
16a53ecc | 3081 | */ |
a4456856 DW |
3082 | if (s.syncing && s.locked == 0 && !test_bit(STRIPE_INSYNC, &sh->state)) |
3083 | handle_parity_checks6(conf, sh, &s, &r6s, tmp_page, disks); | |
16a53ecc | 3084 | |
a4456856 | 3085 | if (s.syncing && s.locked == 0 && test_bit(STRIPE_INSYNC, &sh->state)) { |
16a53ecc N |
3086 | md_done_sync(conf->mddev, STRIPE_SECTORS,1); |
3087 | clear_bit(STRIPE_SYNCING, &sh->state); | |
3088 | } | |
3089 | ||
3090 | /* If the failed drives are just a ReadError, then we might need | |
3091 | * to progress the repair/check process | |
3092 | */ | |
a4456856 DW |
3093 | if (s.failed <= 2 && !conf->mddev->ro) |
3094 | for (i = 0; i < s.failed; i++) { | |
3095 | dev = &sh->dev[r6s.failed_num[i]]; | |
16a53ecc N |
3096 | if (test_bit(R5_ReadError, &dev->flags) |
3097 | && !test_bit(R5_LOCKED, &dev->flags) | |
3098 | && test_bit(R5_UPTODATE, &dev->flags) | |
3099 | ) { | |
3100 | if (!test_bit(R5_ReWrite, &dev->flags)) { | |
3101 | set_bit(R5_Wantwrite, &dev->flags); | |
3102 | set_bit(R5_ReWrite, &dev->flags); | |
3103 | set_bit(R5_LOCKED, &dev->flags); | |
3104 | } else { | |
3105 | /* let's read it back */ | |
3106 | set_bit(R5_Wantread, &dev->flags); | |
3107 | set_bit(R5_LOCKED, &dev->flags); | |
3108 | } | |
3109 | } | |
3110 | } | |
f416885e | 3111 | |
a4456856 | 3112 | if (s.expanded && test_bit(STRIPE_EXPANDING, &sh->state)) { |
f416885e N |
3113 | /* Need to write out all blocks after computing P&Q */ |
3114 | sh->disks = conf->raid_disks; | |
3115 | sh->pd_idx = stripe_to_pdidx(sh->sector, conf, | |
3116 | conf->raid_disks); | |
3117 | compute_parity6(sh, RECONSTRUCT_WRITE); | |
3118 | for (i = conf->raid_disks ; i-- ; ) { | |
3119 | set_bit(R5_LOCKED, &sh->dev[i].flags); | |
a4456856 | 3120 | s.locked++; |
f416885e N |
3121 | set_bit(R5_Wantwrite, &sh->dev[i].flags); |
3122 | } | |
3123 | clear_bit(STRIPE_EXPANDING, &sh->state); | |
a4456856 | 3124 | } else if (s.expanded) { |
f416885e N |
3125 | clear_bit(STRIPE_EXPAND_READY, &sh->state); |
3126 | atomic_dec(&conf->reshape_stripes); | |
3127 | wake_up(&conf->wait_for_overlap); | |
3128 | md_done_sync(conf->mddev, STRIPE_SECTORS, 1); | |
3129 | } | |
3130 | ||
0f94e87c DW |
3131 | if (s.expanding && s.locked == 0 && |
3132 | !test_bit(STRIPE_OP_COMPUTE_BLK, &sh->ops.pending)) | |
a4456856 | 3133 | handle_stripe_expansion(conf, sh, &r6s); |
f416885e | 3134 | |
6bfe0b49 | 3135 | unlock: |
16a53ecc N |
3136 | spin_unlock(&sh->lock); |
3137 | ||
6bfe0b49 DW |
3138 | /* wait for this device to become unblocked */ |
3139 | if (unlikely(blocked_rdev)) | |
3140 | md_wait_for_blocked_rdev(blocked_rdev, conf->mddev); | |
3141 | ||
a4456856 | 3142 | return_io(return_bi); |
16a53ecc | 3143 | |
16a53ecc N |
3144 | for (i=disks; i-- ;) { |
3145 | int rw; | |
3146 | struct bio *bi; | |
3147 | mdk_rdev_t *rdev; | |
3148 | if (test_and_clear_bit(R5_Wantwrite, &sh->dev[i].flags)) | |
802ba064 | 3149 | rw = WRITE; |
16a53ecc | 3150 | else if (test_and_clear_bit(R5_Wantread, &sh->dev[i].flags)) |
802ba064 | 3151 | rw = READ; |
16a53ecc N |
3152 | else |
3153 | continue; | |
3154 | ||
8b3e6cdc DW |
3155 | set_bit(STRIPE_IO_STARTED, &sh->state); |
3156 | ||
16a53ecc N |
3157 | bi = &sh->dev[i].req; |
3158 | ||
3159 | bi->bi_rw = rw; | |
802ba064 | 3160 | if (rw == WRITE) |
16a53ecc N |
3161 | bi->bi_end_io = raid5_end_write_request; |
3162 | else | |
3163 | bi->bi_end_io = raid5_end_read_request; | |
3164 | ||
3165 | rcu_read_lock(); | |
3166 | rdev = rcu_dereference(conf->disks[i].rdev); | |
3167 | if (rdev && test_bit(Faulty, &rdev->flags)) | |
3168 | rdev = NULL; | |
3169 | if (rdev) | |
3170 | atomic_inc(&rdev->nr_pending); | |
3171 | rcu_read_unlock(); | |
3172 | ||
3173 | if (rdev) { | |
a4456856 | 3174 | if (s.syncing || s.expanding || s.expanded) |
16a53ecc N |
3175 | md_sync_acct(rdev->bdev, STRIPE_SECTORS); |
3176 | ||
3177 | bi->bi_bdev = rdev->bdev; | |
45b4233c | 3178 | pr_debug("for %llu schedule op %ld on disc %d\n", |
16a53ecc N |
3179 | (unsigned long long)sh->sector, bi->bi_rw, i); |
3180 | atomic_inc(&sh->count); | |
3181 | bi->bi_sector = sh->sector + rdev->data_offset; | |
3182 | bi->bi_flags = 1 << BIO_UPTODATE; | |
3183 | bi->bi_vcnt = 1; | |
3184 | bi->bi_max_vecs = 1; | |
3185 | bi->bi_idx = 0; | |
3186 | bi->bi_io_vec = &sh->dev[i].vec; | |
3187 | bi->bi_io_vec[0].bv_len = STRIPE_SIZE; | |
3188 | bi->bi_io_vec[0].bv_offset = 0; | |
3189 | bi->bi_size = STRIPE_SIZE; | |
3190 | bi->bi_next = NULL; | |
3191 | if (rw == WRITE && | |
3192 | test_bit(R5_ReWrite, &sh->dev[i].flags)) | |
3193 | atomic_add(STRIPE_SECTORS, &rdev->corrected_errors); | |
3194 | generic_make_request(bi); | |
3195 | } else { | |
802ba064 | 3196 | if (rw == WRITE) |
16a53ecc | 3197 | set_bit(STRIPE_DEGRADED, &sh->state); |
45b4233c | 3198 | pr_debug("skip op %ld on disc %d for sector %llu\n", |
16a53ecc N |
3199 | bi->bi_rw, i, (unsigned long long)sh->sector); |
3200 | clear_bit(R5_LOCKED, &sh->dev[i].flags); | |
3201 | set_bit(STRIPE_HANDLE, &sh->state); | |
3202 | } | |
3203 | } | |
3204 | } | |
3205 | ||
3206 | static void handle_stripe(struct stripe_head *sh, struct page *tmp_page) | |
3207 | { | |
3208 | if (sh->raid_conf->level == 6) | |
3209 | handle_stripe6(sh, tmp_page); | |
3210 | else | |
3211 | handle_stripe5(sh); | |
3212 | } | |
3213 | ||
3214 | ||
3215 | ||
3216 | static void raid5_activate_delayed(raid5_conf_t *conf) | |
3217 | { | |
3218 | if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD) { | |
3219 | while (!list_empty(&conf->delayed_list)) { | |
3220 | struct list_head *l = conf->delayed_list.next; | |
3221 | struct stripe_head *sh; | |
3222 | sh = list_entry(l, struct stripe_head, lru); | |
3223 | list_del_init(l); | |
3224 | clear_bit(STRIPE_DELAYED, &sh->state); | |
3225 | if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) | |
3226 | atomic_inc(&conf->preread_active_stripes); | |
8b3e6cdc | 3227 | list_add_tail(&sh->lru, &conf->hold_list); |
16a53ecc | 3228 | } |
6ed3003c N |
3229 | } else |
3230 | blk_plug_device(conf->mddev->queue); | |
16a53ecc N |
3231 | } |
3232 | ||
3233 | static void activate_bit_delay(raid5_conf_t *conf) | |
3234 | { | |
3235 | /* device_lock is held */ | |
3236 | struct list_head head; | |
3237 | list_add(&head, &conf->bitmap_list); | |
3238 | list_del_init(&conf->bitmap_list); | |
3239 | while (!list_empty(&head)) { | |
3240 | struct stripe_head *sh = list_entry(head.next, struct stripe_head, lru); | |
3241 | list_del_init(&sh->lru); | |
3242 | atomic_inc(&sh->count); | |
3243 | __release_stripe(conf, sh); | |
3244 | } | |
3245 | } | |
3246 | ||
3247 | static void unplug_slaves(mddev_t *mddev) | |
3248 | { | |
3249 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
3250 | int i; | |
3251 | ||
3252 | rcu_read_lock(); | |
3253 | for (i=0; i<mddev->raid_disks; i++) { | |
3254 | mdk_rdev_t *rdev = rcu_dereference(conf->disks[i].rdev); | |
3255 | if (rdev && !test_bit(Faulty, &rdev->flags) && atomic_read(&rdev->nr_pending)) { | |
165125e1 | 3256 | struct request_queue *r_queue = bdev_get_queue(rdev->bdev); |
16a53ecc N |
3257 | |
3258 | atomic_inc(&rdev->nr_pending); | |
3259 | rcu_read_unlock(); | |
3260 | ||
2ad8b1ef | 3261 | blk_unplug(r_queue); |
16a53ecc N |
3262 | |
3263 | rdev_dec_pending(rdev, mddev); | |
3264 | rcu_read_lock(); | |
3265 | } | |
3266 | } | |
3267 | rcu_read_unlock(); | |
3268 | } | |
3269 | ||
165125e1 | 3270 | static void raid5_unplug_device(struct request_queue *q) |
16a53ecc N |
3271 | { |
3272 | mddev_t *mddev = q->queuedata; | |
3273 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
3274 | unsigned long flags; | |
3275 | ||
3276 | spin_lock_irqsave(&conf->device_lock, flags); | |
3277 | ||
3278 | if (blk_remove_plug(q)) { | |
3279 | conf->seq_flush++; | |
3280 | raid5_activate_delayed(conf); | |
72626685 | 3281 | } |
1da177e4 LT |
3282 | md_wakeup_thread(mddev->thread); |
3283 | ||
3284 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
3285 | ||
3286 | unplug_slaves(mddev); | |
3287 | } | |
3288 | ||
f022b2fd N |
3289 | static int raid5_congested(void *data, int bits) |
3290 | { | |
3291 | mddev_t *mddev = data; | |
3292 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
3293 | ||
3294 | /* No difference between reads and writes. Just check | |
3295 | * how busy the stripe_cache is | |
3296 | */ | |
3297 | if (conf->inactive_blocked) | |
3298 | return 1; | |
3299 | if (conf->quiesce) | |
3300 | return 1; | |
3301 | if (list_empty_careful(&conf->inactive_list)) | |
3302 | return 1; | |
3303 | ||
3304 | return 0; | |
3305 | } | |
3306 | ||
23032a0e RBJ |
3307 | /* We want read requests to align with chunks where possible, |
3308 | * but write requests don't need to. | |
3309 | */ | |
165125e1 | 3310 | static int raid5_mergeable_bvec(struct request_queue *q, struct bio *bio, struct bio_vec *biovec) |
23032a0e RBJ |
3311 | { |
3312 | mddev_t *mddev = q->queuedata; | |
3313 | sector_t sector = bio->bi_sector + get_start_sect(bio->bi_bdev); | |
3314 | int max; | |
3315 | unsigned int chunk_sectors = mddev->chunk_size >> 9; | |
3316 | unsigned int bio_sectors = bio->bi_size >> 9; | |
3317 | ||
802ba064 | 3318 | if (bio_data_dir(bio) == WRITE) |
23032a0e RBJ |
3319 | return biovec->bv_len; /* always allow writes to be mergeable */ |
3320 | ||
3321 | max = (chunk_sectors - ((sector & (chunk_sectors - 1)) + bio_sectors)) << 9; | |
3322 | if (max < 0) max = 0; | |
3323 | if (max <= biovec->bv_len && bio_sectors == 0) | |
3324 | return biovec->bv_len; | |
3325 | else | |
3326 | return max; | |
3327 | } | |
3328 | ||
f679623f RBJ |
3329 | |
3330 | static int in_chunk_boundary(mddev_t *mddev, struct bio *bio) | |
3331 | { | |
3332 | sector_t sector = bio->bi_sector + get_start_sect(bio->bi_bdev); | |
3333 | unsigned int chunk_sectors = mddev->chunk_size >> 9; | |
3334 | unsigned int bio_sectors = bio->bi_size >> 9; | |
3335 | ||
3336 | return chunk_sectors >= | |
3337 | ((sector & (chunk_sectors - 1)) + bio_sectors); | |
3338 | } | |
3339 | ||
46031f9a RBJ |
3340 | /* |
3341 | * add bio to the retry LIFO ( in O(1) ... we are in interrupt ) | |
3342 | * later sampled by raid5d. | |
3343 | */ | |
3344 | static void add_bio_to_retry(struct bio *bi,raid5_conf_t *conf) | |
3345 | { | |
3346 | unsigned long flags; | |
3347 | ||
3348 | spin_lock_irqsave(&conf->device_lock, flags); | |
3349 | ||
3350 | bi->bi_next = conf->retry_read_aligned_list; | |
3351 | conf->retry_read_aligned_list = bi; | |
3352 | ||
3353 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
3354 | md_wakeup_thread(conf->mddev->thread); | |
3355 | } | |
3356 | ||
3357 | ||
3358 | static struct bio *remove_bio_from_retry(raid5_conf_t *conf) | |
3359 | { | |
3360 | struct bio *bi; | |
3361 | ||
3362 | bi = conf->retry_read_aligned; | |
3363 | if (bi) { | |
3364 | conf->retry_read_aligned = NULL; | |
3365 | return bi; | |
3366 | } | |
3367 | bi = conf->retry_read_aligned_list; | |
3368 | if(bi) { | |
387bb173 | 3369 | conf->retry_read_aligned_list = bi->bi_next; |
46031f9a RBJ |
3370 | bi->bi_next = NULL; |
3371 | bi->bi_phys_segments = 1; /* biased count of active stripes */ | |
3372 | bi->bi_hw_segments = 0; /* count of processed stripes */ | |
3373 | } | |
3374 | ||
3375 | return bi; | |
3376 | } | |
3377 | ||
3378 | ||
f679623f RBJ |
3379 | /* |
3380 | * The "raid5_align_endio" should check if the read succeeded and if it | |
3381 | * did, call bio_endio on the original bio (having bio_put the new bio | |
3382 | * first). | |
3383 | * If the read failed.. | |
3384 | */ | |
6712ecf8 | 3385 | static void raid5_align_endio(struct bio *bi, int error) |
f679623f RBJ |
3386 | { |
3387 | struct bio* raid_bi = bi->bi_private; | |
46031f9a RBJ |
3388 | mddev_t *mddev; |
3389 | raid5_conf_t *conf; | |
3390 | int uptodate = test_bit(BIO_UPTODATE, &bi->bi_flags); | |
3391 | mdk_rdev_t *rdev; | |
3392 | ||
f679623f | 3393 | bio_put(bi); |
46031f9a RBJ |
3394 | |
3395 | mddev = raid_bi->bi_bdev->bd_disk->queue->queuedata; | |
3396 | conf = mddev_to_conf(mddev); | |
3397 | rdev = (void*)raid_bi->bi_next; | |
3398 | raid_bi->bi_next = NULL; | |
3399 | ||
3400 | rdev_dec_pending(rdev, conf->mddev); | |
3401 | ||
3402 | if (!error && uptodate) { | |
6712ecf8 | 3403 | bio_endio(raid_bi, 0); |
46031f9a RBJ |
3404 | if (atomic_dec_and_test(&conf->active_aligned_reads)) |
3405 | wake_up(&conf->wait_for_stripe); | |
6712ecf8 | 3406 | return; |
46031f9a RBJ |
3407 | } |
3408 | ||
3409 | ||
45b4233c | 3410 | pr_debug("raid5_align_endio : io error...handing IO for a retry\n"); |
46031f9a RBJ |
3411 | |
3412 | add_bio_to_retry(raid_bi, conf); | |
f679623f RBJ |
3413 | } |
3414 | ||
387bb173 NB |
3415 | static int bio_fits_rdev(struct bio *bi) |
3416 | { | |
165125e1 | 3417 | struct request_queue *q = bdev_get_queue(bi->bi_bdev); |
387bb173 NB |
3418 | |
3419 | if ((bi->bi_size>>9) > q->max_sectors) | |
3420 | return 0; | |
3421 | blk_recount_segments(q, bi); | |
3422 | if (bi->bi_phys_segments > q->max_phys_segments || | |
3423 | bi->bi_hw_segments > q->max_hw_segments) | |
3424 | return 0; | |
3425 | ||
3426 | if (q->merge_bvec_fn) | |
3427 | /* it's too hard to apply the merge_bvec_fn at this stage, | |
3428 | * just just give up | |
3429 | */ | |
3430 | return 0; | |
3431 | ||
3432 | return 1; | |
3433 | } | |
3434 | ||
3435 | ||
165125e1 | 3436 | static int chunk_aligned_read(struct request_queue *q, struct bio * raid_bio) |
f679623f RBJ |
3437 | { |
3438 | mddev_t *mddev = q->queuedata; | |
3439 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
3440 | const unsigned int raid_disks = conf->raid_disks; | |
46031f9a | 3441 | const unsigned int data_disks = raid_disks - conf->max_degraded; |
f679623f RBJ |
3442 | unsigned int dd_idx, pd_idx; |
3443 | struct bio* align_bi; | |
3444 | mdk_rdev_t *rdev; | |
3445 | ||
3446 | if (!in_chunk_boundary(mddev, raid_bio)) { | |
45b4233c | 3447 | pr_debug("chunk_aligned_read : non aligned\n"); |
f679623f RBJ |
3448 | return 0; |
3449 | } | |
3450 | /* | |
3451 | * use bio_clone to make a copy of the bio | |
3452 | */ | |
3453 | align_bi = bio_clone(raid_bio, GFP_NOIO); | |
3454 | if (!align_bi) | |
3455 | return 0; | |
3456 | /* | |
3457 | * set bi_end_io to a new function, and set bi_private to the | |
3458 | * original bio. | |
3459 | */ | |
3460 | align_bi->bi_end_io = raid5_align_endio; | |
3461 | align_bi->bi_private = raid_bio; | |
3462 | /* | |
3463 | * compute position | |
3464 | */ | |
3465 | align_bi->bi_sector = raid5_compute_sector(raid_bio->bi_sector, | |
3466 | raid_disks, | |
3467 | data_disks, | |
3468 | &dd_idx, | |
3469 | &pd_idx, | |
3470 | conf); | |
3471 | ||
3472 | rcu_read_lock(); | |
3473 | rdev = rcu_dereference(conf->disks[dd_idx].rdev); | |
3474 | if (rdev && test_bit(In_sync, &rdev->flags)) { | |
f679623f RBJ |
3475 | atomic_inc(&rdev->nr_pending); |
3476 | rcu_read_unlock(); | |
46031f9a RBJ |
3477 | raid_bio->bi_next = (void*)rdev; |
3478 | align_bi->bi_bdev = rdev->bdev; | |
3479 | align_bi->bi_flags &= ~(1 << BIO_SEG_VALID); | |
3480 | align_bi->bi_sector += rdev->data_offset; | |
3481 | ||
387bb173 NB |
3482 | if (!bio_fits_rdev(align_bi)) { |
3483 | /* too big in some way */ | |
3484 | bio_put(align_bi); | |
3485 | rdev_dec_pending(rdev, mddev); | |
3486 | return 0; | |
3487 | } | |
3488 | ||
46031f9a RBJ |
3489 | spin_lock_irq(&conf->device_lock); |
3490 | wait_event_lock_irq(conf->wait_for_stripe, | |
3491 | conf->quiesce == 0, | |
3492 | conf->device_lock, /* nothing */); | |
3493 | atomic_inc(&conf->active_aligned_reads); | |
3494 | spin_unlock_irq(&conf->device_lock); | |
3495 | ||
f679623f RBJ |
3496 | generic_make_request(align_bi); |
3497 | return 1; | |
3498 | } else { | |
3499 | rcu_read_unlock(); | |
46031f9a | 3500 | bio_put(align_bi); |
f679623f RBJ |
3501 | return 0; |
3502 | } | |
3503 | } | |
3504 | ||
8b3e6cdc DW |
3505 | /* __get_priority_stripe - get the next stripe to process |
3506 | * | |
3507 | * Full stripe writes are allowed to pass preread active stripes up until | |
3508 | * the bypass_threshold is exceeded. In general the bypass_count | |
3509 | * increments when the handle_list is handled before the hold_list; however, it | |
3510 | * will not be incremented when STRIPE_IO_STARTED is sampled set signifying a | |
3511 | * stripe with in flight i/o. The bypass_count will be reset when the | |
3512 | * head of the hold_list has changed, i.e. the head was promoted to the | |
3513 | * handle_list. | |
3514 | */ | |
3515 | static struct stripe_head *__get_priority_stripe(raid5_conf_t *conf) | |
3516 | { | |
3517 | struct stripe_head *sh; | |
3518 | ||
3519 | pr_debug("%s: handle: %s hold: %s full_writes: %d bypass_count: %d\n", | |
3520 | __func__, | |
3521 | list_empty(&conf->handle_list) ? "empty" : "busy", | |
3522 | list_empty(&conf->hold_list) ? "empty" : "busy", | |
3523 | atomic_read(&conf->pending_full_writes), conf->bypass_count); | |
3524 | ||
3525 | if (!list_empty(&conf->handle_list)) { | |
3526 | sh = list_entry(conf->handle_list.next, typeof(*sh), lru); | |
3527 | ||
3528 | if (list_empty(&conf->hold_list)) | |
3529 | conf->bypass_count = 0; | |
3530 | else if (!test_bit(STRIPE_IO_STARTED, &sh->state)) { | |
3531 | if (conf->hold_list.next == conf->last_hold) | |
3532 | conf->bypass_count++; | |
3533 | else { | |
3534 | conf->last_hold = conf->hold_list.next; | |
3535 | conf->bypass_count -= conf->bypass_threshold; | |
3536 | if (conf->bypass_count < 0) | |
3537 | conf->bypass_count = 0; | |
3538 | } | |
3539 | } | |
3540 | } else if (!list_empty(&conf->hold_list) && | |
3541 | ((conf->bypass_threshold && | |
3542 | conf->bypass_count > conf->bypass_threshold) || | |
3543 | atomic_read(&conf->pending_full_writes) == 0)) { | |
3544 | sh = list_entry(conf->hold_list.next, | |
3545 | typeof(*sh), lru); | |
3546 | conf->bypass_count -= conf->bypass_threshold; | |
3547 | if (conf->bypass_count < 0) | |
3548 | conf->bypass_count = 0; | |
3549 | } else | |
3550 | return NULL; | |
3551 | ||
3552 | list_del_init(&sh->lru); | |
3553 | atomic_inc(&sh->count); | |
3554 | BUG_ON(atomic_read(&sh->count) != 1); | |
3555 | return sh; | |
3556 | } | |
f679623f | 3557 | |
165125e1 | 3558 | static int make_request(struct request_queue *q, struct bio * bi) |
1da177e4 LT |
3559 | { |
3560 | mddev_t *mddev = q->queuedata; | |
3561 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
1da177e4 LT |
3562 | unsigned int dd_idx, pd_idx; |
3563 | sector_t new_sector; | |
3564 | sector_t logical_sector, last_sector; | |
3565 | struct stripe_head *sh; | |
a362357b | 3566 | const int rw = bio_data_dir(bi); |
f6344757 | 3567 | int remaining; |
1da177e4 | 3568 | |
e5dcdd80 | 3569 | if (unlikely(bio_barrier(bi))) { |
6712ecf8 | 3570 | bio_endio(bi, -EOPNOTSUPP); |
e5dcdd80 N |
3571 | return 0; |
3572 | } | |
3573 | ||
3d310eb7 | 3574 | md_write_start(mddev, bi); |
06d91a5f | 3575 | |
a362357b JA |
3576 | disk_stat_inc(mddev->gendisk, ios[rw]); |
3577 | disk_stat_add(mddev->gendisk, sectors[rw], bio_sectors(bi)); | |
1da177e4 | 3578 | |
802ba064 | 3579 | if (rw == READ && |
52488615 RBJ |
3580 | mddev->reshape_position == MaxSector && |
3581 | chunk_aligned_read(q,bi)) | |
3582 | return 0; | |
3583 | ||
1da177e4 LT |
3584 | logical_sector = bi->bi_sector & ~((sector_t)STRIPE_SECTORS-1); |
3585 | last_sector = bi->bi_sector + (bi->bi_size>>9); | |
3586 | bi->bi_next = NULL; | |
3587 | bi->bi_phys_segments = 1; /* over-loaded to count active stripes */ | |
06d91a5f | 3588 | |
1da177e4 LT |
3589 | for (;logical_sector < last_sector; logical_sector += STRIPE_SECTORS) { |
3590 | DEFINE_WAIT(w); | |
16a53ecc | 3591 | int disks, data_disks; |
b578d55f | 3592 | |
7ecaa1e6 | 3593 | retry: |
b578d55f | 3594 | prepare_to_wait(&conf->wait_for_overlap, &w, TASK_UNINTERRUPTIBLE); |
7ecaa1e6 N |
3595 | if (likely(conf->expand_progress == MaxSector)) |
3596 | disks = conf->raid_disks; | |
3597 | else { | |
df8e7f76 N |
3598 | /* spinlock is needed as expand_progress may be |
3599 | * 64bit on a 32bit platform, and so it might be | |
3600 | * possible to see a half-updated value | |
3601 | * Ofcourse expand_progress could change after | |
3602 | * the lock is dropped, so once we get a reference | |
3603 | * to the stripe that we think it is, we will have | |
3604 | * to check again. | |
3605 | */ | |
7ecaa1e6 N |
3606 | spin_lock_irq(&conf->device_lock); |
3607 | disks = conf->raid_disks; | |
3608 | if (logical_sector >= conf->expand_progress) | |
3609 | disks = conf->previous_raid_disks; | |
b578d55f N |
3610 | else { |
3611 | if (logical_sector >= conf->expand_lo) { | |
3612 | spin_unlock_irq(&conf->device_lock); | |
3613 | schedule(); | |
3614 | goto retry; | |
3615 | } | |
3616 | } | |
7ecaa1e6 N |
3617 | spin_unlock_irq(&conf->device_lock); |
3618 | } | |
16a53ecc N |
3619 | data_disks = disks - conf->max_degraded; |
3620 | ||
3621 | new_sector = raid5_compute_sector(logical_sector, disks, data_disks, | |
7ecaa1e6 | 3622 | &dd_idx, &pd_idx, conf); |
45b4233c | 3623 | pr_debug("raid5: make_request, sector %llu logical %llu\n", |
1da177e4 LT |
3624 | (unsigned long long)new_sector, |
3625 | (unsigned long long)logical_sector); | |
3626 | ||
7ecaa1e6 | 3627 | sh = get_active_stripe(conf, new_sector, disks, pd_idx, (bi->bi_rw&RWA_MASK)); |
1da177e4 | 3628 | if (sh) { |
7ecaa1e6 N |
3629 | if (unlikely(conf->expand_progress != MaxSector)) { |
3630 | /* expansion might have moved on while waiting for a | |
df8e7f76 N |
3631 | * stripe, so we must do the range check again. |
3632 | * Expansion could still move past after this | |
3633 | * test, but as we are holding a reference to | |
3634 | * 'sh', we know that if that happens, | |
3635 | * STRIPE_EXPANDING will get set and the expansion | |
3636 | * won't proceed until we finish with the stripe. | |
7ecaa1e6 N |
3637 | */ |
3638 | int must_retry = 0; | |
3639 | spin_lock_irq(&conf->device_lock); | |
3640 | if (logical_sector < conf->expand_progress && | |
3641 | disks == conf->previous_raid_disks) | |
3642 | /* mismatch, need to try again */ | |
3643 | must_retry = 1; | |
3644 | spin_unlock_irq(&conf->device_lock); | |
3645 | if (must_retry) { | |
3646 | release_stripe(sh); | |
3647 | goto retry; | |
3648 | } | |
3649 | } | |
e464eafd N |
3650 | /* FIXME what if we get a false positive because these |
3651 | * are being updated. | |
3652 | */ | |
3653 | if (logical_sector >= mddev->suspend_lo && | |
3654 | logical_sector < mddev->suspend_hi) { | |
3655 | release_stripe(sh); | |
3656 | schedule(); | |
3657 | goto retry; | |
3658 | } | |
7ecaa1e6 N |
3659 | |
3660 | if (test_bit(STRIPE_EXPANDING, &sh->state) || | |
3661 | !add_stripe_bio(sh, bi, dd_idx, (bi->bi_rw&RW_MASK))) { | |
3662 | /* Stripe is busy expanding or | |
3663 | * add failed due to overlap. Flush everything | |
1da177e4 LT |
3664 | * and wait a while |
3665 | */ | |
3666 | raid5_unplug_device(mddev->queue); | |
3667 | release_stripe(sh); | |
3668 | schedule(); | |
3669 | goto retry; | |
3670 | } | |
3671 | finish_wait(&conf->wait_for_overlap, &w); | |
6ed3003c N |
3672 | set_bit(STRIPE_HANDLE, &sh->state); |
3673 | clear_bit(STRIPE_DELAYED, &sh->state); | |
1da177e4 | 3674 | release_stripe(sh); |
1da177e4 LT |
3675 | } else { |
3676 | /* cannot get stripe for read-ahead, just give-up */ | |
3677 | clear_bit(BIO_UPTODATE, &bi->bi_flags); | |
3678 | finish_wait(&conf->wait_for_overlap, &w); | |
3679 | break; | |
3680 | } | |
3681 | ||
3682 | } | |
3683 | spin_lock_irq(&conf->device_lock); | |
f6344757 N |
3684 | remaining = --bi->bi_phys_segments; |
3685 | spin_unlock_irq(&conf->device_lock); | |
3686 | if (remaining == 0) { | |
1da177e4 | 3687 | |
16a53ecc | 3688 | if ( rw == WRITE ) |
1da177e4 | 3689 | md_write_end(mddev); |
6712ecf8 | 3690 | |
0e13fe23 | 3691 | bio_endio(bi, 0); |
1da177e4 | 3692 | } |
1da177e4 LT |
3693 | return 0; |
3694 | } | |
3695 | ||
52c03291 | 3696 | static sector_t reshape_request(mddev_t *mddev, sector_t sector_nr, int *skipped) |
1da177e4 | 3697 | { |
52c03291 N |
3698 | /* reshaping is quite different to recovery/resync so it is |
3699 | * handled quite separately ... here. | |
3700 | * | |
3701 | * On each call to sync_request, we gather one chunk worth of | |
3702 | * destination stripes and flag them as expanding. | |
3703 | * Then we find all the source stripes and request reads. | |
3704 | * As the reads complete, handle_stripe will copy the data | |
3705 | * into the destination stripe and release that stripe. | |
3706 | */ | |
1da177e4 LT |
3707 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; |
3708 | struct stripe_head *sh; | |
ccfcc3c1 N |
3709 | int pd_idx; |
3710 | sector_t first_sector, last_sector; | |
f416885e N |
3711 | int raid_disks = conf->previous_raid_disks; |
3712 | int data_disks = raid_disks - conf->max_degraded; | |
3713 | int new_data_disks = conf->raid_disks - conf->max_degraded; | |
52c03291 N |
3714 | int i; |
3715 | int dd_idx; | |
3716 | sector_t writepos, safepos, gap; | |
3717 | ||
3718 | if (sector_nr == 0 && | |
3719 | conf->expand_progress != 0) { | |
3720 | /* restarting in the middle, skip the initial sectors */ | |
3721 | sector_nr = conf->expand_progress; | |
f416885e | 3722 | sector_div(sector_nr, new_data_disks); |
52c03291 N |
3723 | *skipped = 1; |
3724 | return sector_nr; | |
3725 | } | |
3726 | ||
3727 | /* we update the metadata when there is more than 3Meg | |
3728 | * in the block range (that is rather arbitrary, should | |
3729 | * probably be time based) or when the data about to be | |
3730 | * copied would over-write the source of the data at | |
3731 | * the front of the range. | |
3732 | * i.e. one new_stripe forward from expand_progress new_maps | |
3733 | * to after where expand_lo old_maps to | |
3734 | */ | |
3735 | writepos = conf->expand_progress + | |
f416885e N |
3736 | conf->chunk_size/512*(new_data_disks); |
3737 | sector_div(writepos, new_data_disks); | |
52c03291 | 3738 | safepos = conf->expand_lo; |
f416885e | 3739 | sector_div(safepos, data_disks); |
52c03291 N |
3740 | gap = conf->expand_progress - conf->expand_lo; |
3741 | ||
3742 | if (writepos >= safepos || | |
f416885e | 3743 | gap > (new_data_disks)*3000*2 /*3Meg*/) { |
52c03291 N |
3744 | /* Cannot proceed until we've updated the superblock... */ |
3745 | wait_event(conf->wait_for_overlap, | |
3746 | atomic_read(&conf->reshape_stripes)==0); | |
3747 | mddev->reshape_position = conf->expand_progress; | |
850b2b42 | 3748 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
52c03291 | 3749 | md_wakeup_thread(mddev->thread); |
850b2b42 | 3750 | wait_event(mddev->sb_wait, mddev->flags == 0 || |
52c03291 N |
3751 | kthread_should_stop()); |
3752 | spin_lock_irq(&conf->device_lock); | |
3753 | conf->expand_lo = mddev->reshape_position; | |
3754 | spin_unlock_irq(&conf->device_lock); | |
3755 | wake_up(&conf->wait_for_overlap); | |
3756 | } | |
3757 | ||
3758 | for (i=0; i < conf->chunk_size/512; i+= STRIPE_SECTORS) { | |
3759 | int j; | |
3760 | int skipped = 0; | |
3761 | pd_idx = stripe_to_pdidx(sector_nr+i, conf, conf->raid_disks); | |
3762 | sh = get_active_stripe(conf, sector_nr+i, | |
3763 | conf->raid_disks, pd_idx, 0); | |
3764 | set_bit(STRIPE_EXPANDING, &sh->state); | |
3765 | atomic_inc(&conf->reshape_stripes); | |
3766 | /* If any of this stripe is beyond the end of the old | |
3767 | * array, then we need to zero those blocks | |
3768 | */ | |
3769 | for (j=sh->disks; j--;) { | |
3770 | sector_t s; | |
3771 | if (j == sh->pd_idx) | |
3772 | continue; | |
f416885e N |
3773 | if (conf->level == 6 && |
3774 | j == raid6_next_disk(sh->pd_idx, sh->disks)) | |
3775 | continue; | |
52c03291 N |
3776 | s = compute_blocknr(sh, j); |
3777 | if (s < (mddev->array_size<<1)) { | |
3778 | skipped = 1; | |
3779 | continue; | |
3780 | } | |
3781 | memset(page_address(sh->dev[j].page), 0, STRIPE_SIZE); | |
3782 | set_bit(R5_Expanded, &sh->dev[j].flags); | |
3783 | set_bit(R5_UPTODATE, &sh->dev[j].flags); | |
3784 | } | |
3785 | if (!skipped) { | |
3786 | set_bit(STRIPE_EXPAND_READY, &sh->state); | |
3787 | set_bit(STRIPE_HANDLE, &sh->state); | |
3788 | } | |
3789 | release_stripe(sh); | |
3790 | } | |
3791 | spin_lock_irq(&conf->device_lock); | |
6d3baf2e | 3792 | conf->expand_progress = (sector_nr + i) * new_data_disks; |
52c03291 N |
3793 | spin_unlock_irq(&conf->device_lock); |
3794 | /* Ok, those stripe are ready. We can start scheduling | |
3795 | * reads on the source stripes. | |
3796 | * The source stripes are determined by mapping the first and last | |
3797 | * block on the destination stripes. | |
3798 | */ | |
52c03291 | 3799 | first_sector = |
f416885e | 3800 | raid5_compute_sector(sector_nr*(new_data_disks), |
52c03291 N |
3801 | raid_disks, data_disks, |
3802 | &dd_idx, &pd_idx, conf); | |
3803 | last_sector = | |
3804 | raid5_compute_sector((sector_nr+conf->chunk_size/512) | |
f416885e | 3805 | *(new_data_disks) -1, |
52c03291 N |
3806 | raid_disks, data_disks, |
3807 | &dd_idx, &pd_idx, conf); | |
3808 | if (last_sector >= (mddev->size<<1)) | |
3809 | last_sector = (mddev->size<<1)-1; | |
3810 | while (first_sector <= last_sector) { | |
f416885e N |
3811 | pd_idx = stripe_to_pdidx(first_sector, conf, |
3812 | conf->previous_raid_disks); | |
52c03291 N |
3813 | sh = get_active_stripe(conf, first_sector, |
3814 | conf->previous_raid_disks, pd_idx, 0); | |
3815 | set_bit(STRIPE_EXPAND_SOURCE, &sh->state); | |
3816 | set_bit(STRIPE_HANDLE, &sh->state); | |
3817 | release_stripe(sh); | |
3818 | first_sector += STRIPE_SECTORS; | |
3819 | } | |
c6207277 N |
3820 | /* If this takes us to the resync_max point where we have to pause, |
3821 | * then we need to write out the superblock. | |
3822 | */ | |
3823 | sector_nr += conf->chunk_size>>9; | |
3824 | if (sector_nr >= mddev->resync_max) { | |
3825 | /* Cannot proceed until we've updated the superblock... */ | |
3826 | wait_event(conf->wait_for_overlap, | |
3827 | atomic_read(&conf->reshape_stripes) == 0); | |
3828 | mddev->reshape_position = conf->expand_progress; | |
3829 | set_bit(MD_CHANGE_DEVS, &mddev->flags); | |
3830 | md_wakeup_thread(mddev->thread); | |
3831 | wait_event(mddev->sb_wait, | |
3832 | !test_bit(MD_CHANGE_DEVS, &mddev->flags) | |
3833 | || kthread_should_stop()); | |
3834 | spin_lock_irq(&conf->device_lock); | |
3835 | conf->expand_lo = mddev->reshape_position; | |
3836 | spin_unlock_irq(&conf->device_lock); | |
3837 | wake_up(&conf->wait_for_overlap); | |
3838 | } | |
52c03291 N |
3839 | return conf->chunk_size>>9; |
3840 | } | |
3841 | ||
3842 | /* FIXME go_faster isn't used */ | |
3843 | static inline sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, int go_faster) | |
3844 | { | |
3845 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; | |
3846 | struct stripe_head *sh; | |
3847 | int pd_idx; | |
1da177e4 | 3848 | int raid_disks = conf->raid_disks; |
72626685 N |
3849 | sector_t max_sector = mddev->size << 1; |
3850 | int sync_blocks; | |
16a53ecc N |
3851 | int still_degraded = 0; |
3852 | int i; | |
1da177e4 | 3853 | |
72626685 | 3854 | if (sector_nr >= max_sector) { |
1da177e4 LT |
3855 | /* just being told to finish up .. nothing much to do */ |
3856 | unplug_slaves(mddev); | |
29269553 N |
3857 | if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) { |
3858 | end_reshape(conf); | |
3859 | return 0; | |
3860 | } | |
72626685 N |
3861 | |
3862 | if (mddev->curr_resync < max_sector) /* aborted */ | |
3863 | bitmap_end_sync(mddev->bitmap, mddev->curr_resync, | |
3864 | &sync_blocks, 1); | |
16a53ecc | 3865 | else /* completed sync */ |
72626685 N |
3866 | conf->fullsync = 0; |
3867 | bitmap_close_sync(mddev->bitmap); | |
3868 | ||
1da177e4 LT |
3869 | return 0; |
3870 | } | |
ccfcc3c1 | 3871 | |
52c03291 N |
3872 | if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) |
3873 | return reshape_request(mddev, sector_nr, skipped); | |
f6705578 | 3874 | |
c6207277 N |
3875 | /* No need to check resync_max as we never do more than one |
3876 | * stripe, and as resync_max will always be on a chunk boundary, | |
3877 | * if the check in md_do_sync didn't fire, there is no chance | |
3878 | * of overstepping resync_max here | |
3879 | */ | |
3880 | ||
16a53ecc | 3881 | /* if there is too many failed drives and we are trying |
1da177e4 LT |
3882 | * to resync, then assert that we are finished, because there is |
3883 | * nothing we can do. | |
3884 | */ | |
3285edf1 | 3885 | if (mddev->degraded >= conf->max_degraded && |
16a53ecc | 3886 | test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) { |
57afd89f N |
3887 | sector_t rv = (mddev->size << 1) - sector_nr; |
3888 | *skipped = 1; | |
1da177e4 LT |
3889 | return rv; |
3890 | } | |
72626685 | 3891 | if (!bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, 1) && |
3855ad9f | 3892 | !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) && |
72626685 N |
3893 | !conf->fullsync && sync_blocks >= STRIPE_SECTORS) { |
3894 | /* we can skip this block, and probably more */ | |
3895 | sync_blocks /= STRIPE_SECTORS; | |
3896 | *skipped = 1; | |
3897 | return sync_blocks * STRIPE_SECTORS; /* keep things rounded to whole stripes */ | |
3898 | } | |
1da177e4 | 3899 | |
b47490c9 N |
3900 | |
3901 | bitmap_cond_end_sync(mddev->bitmap, sector_nr); | |
3902 | ||
ccfcc3c1 | 3903 | pd_idx = stripe_to_pdidx(sector_nr, conf, raid_disks); |
7ecaa1e6 | 3904 | sh = get_active_stripe(conf, sector_nr, raid_disks, pd_idx, 1); |
1da177e4 | 3905 | if (sh == NULL) { |
7ecaa1e6 | 3906 | sh = get_active_stripe(conf, sector_nr, raid_disks, pd_idx, 0); |
1da177e4 | 3907 | /* make sure we don't swamp the stripe cache if someone else |
16a53ecc | 3908 | * is trying to get access |
1da177e4 | 3909 | */ |
66c006a5 | 3910 | schedule_timeout_uninterruptible(1); |
1da177e4 | 3911 | } |
16a53ecc N |
3912 | /* Need to check if array will still be degraded after recovery/resync |
3913 | * We don't need to check the 'failed' flag as when that gets set, | |
3914 | * recovery aborts. | |
3915 | */ | |
3916 | for (i=0; i<mddev->raid_disks; i++) | |
3917 | if (conf->disks[i].rdev == NULL) | |
3918 | still_degraded = 1; | |
3919 | ||
3920 | bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, still_degraded); | |
3921 | ||
3922 | spin_lock(&sh->lock); | |
1da177e4 LT |
3923 | set_bit(STRIPE_SYNCING, &sh->state); |
3924 | clear_bit(STRIPE_INSYNC, &sh->state); | |
3925 | spin_unlock(&sh->lock); | |
3926 | ||
16a53ecc | 3927 | handle_stripe(sh, NULL); |
1da177e4 LT |
3928 | release_stripe(sh); |
3929 | ||
3930 | return STRIPE_SECTORS; | |
3931 | } | |
3932 | ||
46031f9a RBJ |
3933 | static int retry_aligned_read(raid5_conf_t *conf, struct bio *raid_bio) |
3934 | { | |
3935 | /* We may not be able to submit a whole bio at once as there | |
3936 | * may not be enough stripe_heads available. | |
3937 | * We cannot pre-allocate enough stripe_heads as we may need | |
3938 | * more than exist in the cache (if we allow ever large chunks). | |
3939 | * So we do one stripe head at a time and record in | |
3940 | * ->bi_hw_segments how many have been done. | |
3941 | * | |
3942 | * We *know* that this entire raid_bio is in one chunk, so | |
3943 | * it will be only one 'dd_idx' and only need one call to raid5_compute_sector. | |
3944 | */ | |
3945 | struct stripe_head *sh; | |
3946 | int dd_idx, pd_idx; | |
3947 | sector_t sector, logical_sector, last_sector; | |
3948 | int scnt = 0; | |
3949 | int remaining; | |
3950 | int handled = 0; | |
3951 | ||
3952 | logical_sector = raid_bio->bi_sector & ~((sector_t)STRIPE_SECTORS-1); | |
3953 | sector = raid5_compute_sector( logical_sector, | |
3954 | conf->raid_disks, | |
3955 | conf->raid_disks - conf->max_degraded, | |
3956 | &dd_idx, | |
3957 | &pd_idx, | |
3958 | conf); | |
3959 | last_sector = raid_bio->bi_sector + (raid_bio->bi_size>>9); | |
3960 | ||
3961 | for (; logical_sector < last_sector; | |
387bb173 NB |
3962 | logical_sector += STRIPE_SECTORS, |
3963 | sector += STRIPE_SECTORS, | |
3964 | scnt++) { | |
46031f9a RBJ |
3965 | |
3966 | if (scnt < raid_bio->bi_hw_segments) | |
3967 | /* already done this stripe */ | |
3968 | continue; | |
3969 | ||
3970 | sh = get_active_stripe(conf, sector, conf->raid_disks, pd_idx, 1); | |
3971 | ||
3972 | if (!sh) { | |
3973 | /* failed to get a stripe - must wait */ | |
3974 | raid_bio->bi_hw_segments = scnt; | |
3975 | conf->retry_read_aligned = raid_bio; | |
3976 | return handled; | |
3977 | } | |
3978 | ||
3979 | set_bit(R5_ReadError, &sh->dev[dd_idx].flags); | |
387bb173 NB |
3980 | if (!add_stripe_bio(sh, raid_bio, dd_idx, 0)) { |
3981 | release_stripe(sh); | |
3982 | raid_bio->bi_hw_segments = scnt; | |
3983 | conf->retry_read_aligned = raid_bio; | |
3984 | return handled; | |
3985 | } | |
3986 | ||
46031f9a RBJ |
3987 | handle_stripe(sh, NULL); |
3988 | release_stripe(sh); | |
3989 | handled++; | |
3990 | } | |
3991 | spin_lock_irq(&conf->device_lock); | |
3992 | remaining = --raid_bio->bi_phys_segments; | |
3993 | spin_unlock_irq(&conf->device_lock); | |
0e13fe23 NB |
3994 | if (remaining == 0) |
3995 | bio_endio(raid_bio, 0); | |
46031f9a RBJ |
3996 | if (atomic_dec_and_test(&conf->active_aligned_reads)) |
3997 | wake_up(&conf->wait_for_stripe); | |
3998 | return handled; | |
3999 | } | |
4000 | ||
4001 | ||
4002 | ||
1da177e4 LT |
4003 | /* |
4004 | * This is our raid5 kernel thread. | |
4005 | * | |
4006 | * We scan the hash table for stripes which can be handled now. | |
4007 | * During the scan, completed stripes are saved for us by the interrupt | |
4008 | * handler, so that they will not have to wait for our next wakeup. | |
4009 | */ | |
6ed3003c | 4010 | static void raid5d(mddev_t *mddev) |
1da177e4 LT |
4011 | { |
4012 | struct stripe_head *sh; | |
4013 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4014 | int handled; | |
4015 | ||
45b4233c | 4016 | pr_debug("+++ raid5d active\n"); |
1da177e4 LT |
4017 | |
4018 | md_check_recovery(mddev); | |
1da177e4 LT |
4019 | |
4020 | handled = 0; | |
4021 | spin_lock_irq(&conf->device_lock); | |
4022 | while (1) { | |
46031f9a | 4023 | struct bio *bio; |
1da177e4 | 4024 | |
ae3c20cc | 4025 | if (conf->seq_flush != conf->seq_write) { |
72626685 | 4026 | int seq = conf->seq_flush; |
700e432d | 4027 | spin_unlock_irq(&conf->device_lock); |
72626685 | 4028 | bitmap_unplug(mddev->bitmap); |
700e432d | 4029 | spin_lock_irq(&conf->device_lock); |
72626685 N |
4030 | conf->seq_write = seq; |
4031 | activate_bit_delay(conf); | |
4032 | } | |
4033 | ||
46031f9a RBJ |
4034 | while ((bio = remove_bio_from_retry(conf))) { |
4035 | int ok; | |
4036 | spin_unlock_irq(&conf->device_lock); | |
4037 | ok = retry_aligned_read(conf, bio); | |
4038 | spin_lock_irq(&conf->device_lock); | |
4039 | if (!ok) | |
4040 | break; | |
4041 | handled++; | |
4042 | } | |
4043 | ||
8b3e6cdc DW |
4044 | sh = __get_priority_stripe(conf); |
4045 | ||
4046 | if (!sh) { | |
d84e0f10 | 4047 | async_tx_issue_pending_all(); |
1da177e4 | 4048 | break; |
d84e0f10 | 4049 | } |
1da177e4 LT |
4050 | spin_unlock_irq(&conf->device_lock); |
4051 | ||
4052 | handled++; | |
16a53ecc | 4053 | handle_stripe(sh, conf->spare_page); |
1da177e4 LT |
4054 | release_stripe(sh); |
4055 | ||
4056 | spin_lock_irq(&conf->device_lock); | |
4057 | } | |
45b4233c | 4058 | pr_debug("%d stripes handled\n", handled); |
1da177e4 LT |
4059 | |
4060 | spin_unlock_irq(&conf->device_lock); | |
4061 | ||
4062 | unplug_slaves(mddev); | |
4063 | ||
45b4233c | 4064 | pr_debug("--- raid5d inactive\n"); |
1da177e4 LT |
4065 | } |
4066 | ||
3f294f4f | 4067 | static ssize_t |
007583c9 | 4068 | raid5_show_stripe_cache_size(mddev_t *mddev, char *page) |
3f294f4f | 4069 | { |
007583c9 | 4070 | raid5_conf_t *conf = mddev_to_conf(mddev); |
96de1e66 N |
4071 | if (conf) |
4072 | return sprintf(page, "%d\n", conf->max_nr_stripes); | |
4073 | else | |
4074 | return 0; | |
3f294f4f N |
4075 | } |
4076 | ||
4077 | static ssize_t | |
007583c9 | 4078 | raid5_store_stripe_cache_size(mddev_t *mddev, const char *page, size_t len) |
3f294f4f | 4079 | { |
007583c9 | 4080 | raid5_conf_t *conf = mddev_to_conf(mddev); |
4ef197d8 | 4081 | unsigned long new; |
3f294f4f N |
4082 | if (len >= PAGE_SIZE) |
4083 | return -EINVAL; | |
96de1e66 N |
4084 | if (!conf) |
4085 | return -ENODEV; | |
3f294f4f | 4086 | |
4ef197d8 | 4087 | if (strict_strtoul(page, 10, &new)) |
3f294f4f N |
4088 | return -EINVAL; |
4089 | if (new <= 16 || new > 32768) | |
4090 | return -EINVAL; | |
4091 | while (new < conf->max_nr_stripes) { | |
4092 | if (drop_one_stripe(conf)) | |
4093 | conf->max_nr_stripes--; | |
4094 | else | |
4095 | break; | |
4096 | } | |
2a2275d6 | 4097 | md_allow_write(mddev); |
3f294f4f N |
4098 | while (new > conf->max_nr_stripes) { |
4099 | if (grow_one_stripe(conf)) | |
4100 | conf->max_nr_stripes++; | |
4101 | else break; | |
4102 | } | |
4103 | return len; | |
4104 | } | |
007583c9 | 4105 | |
96de1e66 N |
4106 | static struct md_sysfs_entry |
4107 | raid5_stripecache_size = __ATTR(stripe_cache_size, S_IRUGO | S_IWUSR, | |
4108 | raid5_show_stripe_cache_size, | |
4109 | raid5_store_stripe_cache_size); | |
3f294f4f | 4110 | |
8b3e6cdc DW |
4111 | static ssize_t |
4112 | raid5_show_preread_threshold(mddev_t *mddev, char *page) | |
4113 | { | |
4114 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4115 | if (conf) | |
4116 | return sprintf(page, "%d\n", conf->bypass_threshold); | |
4117 | else | |
4118 | return 0; | |
4119 | } | |
4120 | ||
4121 | static ssize_t | |
4122 | raid5_store_preread_threshold(mddev_t *mddev, const char *page, size_t len) | |
4123 | { | |
4124 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4ef197d8 | 4125 | unsigned long new; |
8b3e6cdc DW |
4126 | if (len >= PAGE_SIZE) |
4127 | return -EINVAL; | |
4128 | if (!conf) | |
4129 | return -ENODEV; | |
4130 | ||
4ef197d8 | 4131 | if (strict_strtoul(page, 10, &new)) |
8b3e6cdc | 4132 | return -EINVAL; |
4ef197d8 | 4133 | if (new > conf->max_nr_stripes) |
8b3e6cdc DW |
4134 | return -EINVAL; |
4135 | conf->bypass_threshold = new; | |
4136 | return len; | |
4137 | } | |
4138 | ||
4139 | static struct md_sysfs_entry | |
4140 | raid5_preread_bypass_threshold = __ATTR(preread_bypass_threshold, | |
4141 | S_IRUGO | S_IWUSR, | |
4142 | raid5_show_preread_threshold, | |
4143 | raid5_store_preread_threshold); | |
4144 | ||
3f294f4f | 4145 | static ssize_t |
96de1e66 | 4146 | stripe_cache_active_show(mddev_t *mddev, char *page) |
3f294f4f | 4147 | { |
007583c9 | 4148 | raid5_conf_t *conf = mddev_to_conf(mddev); |
96de1e66 N |
4149 | if (conf) |
4150 | return sprintf(page, "%d\n", atomic_read(&conf->active_stripes)); | |
4151 | else | |
4152 | return 0; | |
3f294f4f N |
4153 | } |
4154 | ||
96de1e66 N |
4155 | static struct md_sysfs_entry |
4156 | raid5_stripecache_active = __ATTR_RO(stripe_cache_active); | |
3f294f4f | 4157 | |
007583c9 | 4158 | static struct attribute *raid5_attrs[] = { |
3f294f4f N |
4159 | &raid5_stripecache_size.attr, |
4160 | &raid5_stripecache_active.attr, | |
8b3e6cdc | 4161 | &raid5_preread_bypass_threshold.attr, |
3f294f4f N |
4162 | NULL, |
4163 | }; | |
007583c9 N |
4164 | static struct attribute_group raid5_attrs_group = { |
4165 | .name = NULL, | |
4166 | .attrs = raid5_attrs, | |
3f294f4f N |
4167 | }; |
4168 | ||
72626685 | 4169 | static int run(mddev_t *mddev) |
1da177e4 LT |
4170 | { |
4171 | raid5_conf_t *conf; | |
4172 | int raid_disk, memory; | |
4173 | mdk_rdev_t *rdev; | |
4174 | struct disk_info *disk; | |
4175 | struct list_head *tmp; | |
02c2de8c | 4176 | int working_disks = 0; |
1da177e4 | 4177 | |
16a53ecc N |
4178 | if (mddev->level != 5 && mddev->level != 4 && mddev->level != 6) { |
4179 | printk(KERN_ERR "raid5: %s: raid level not set to 4/5/6 (%d)\n", | |
14f8d26b | 4180 | mdname(mddev), mddev->level); |
1da177e4 LT |
4181 | return -EIO; |
4182 | } | |
4183 | ||
f6705578 N |
4184 | if (mddev->reshape_position != MaxSector) { |
4185 | /* Check that we can continue the reshape. | |
4186 | * Currently only disks can change, it must | |
4187 | * increase, and we must be past the point where | |
4188 | * a stripe over-writes itself | |
4189 | */ | |
4190 | sector_t here_new, here_old; | |
4191 | int old_disks; | |
f416885e | 4192 | int max_degraded = (mddev->level == 5 ? 1 : 2); |
f6705578 N |
4193 | |
4194 | if (mddev->new_level != mddev->level || | |
4195 | mddev->new_layout != mddev->layout || | |
4196 | mddev->new_chunk != mddev->chunk_size) { | |
f416885e N |
4197 | printk(KERN_ERR "raid5: %s: unsupported reshape " |
4198 | "required - aborting.\n", | |
f6705578 N |
4199 | mdname(mddev)); |
4200 | return -EINVAL; | |
4201 | } | |
4202 | if (mddev->delta_disks <= 0) { | |
f416885e N |
4203 | printk(KERN_ERR "raid5: %s: unsupported reshape " |
4204 | "(reduce disks) required - aborting.\n", | |
f6705578 N |
4205 | mdname(mddev)); |
4206 | return -EINVAL; | |
4207 | } | |
4208 | old_disks = mddev->raid_disks - mddev->delta_disks; | |
4209 | /* reshape_position must be on a new-stripe boundary, and one | |
f416885e N |
4210 | * further up in new geometry must map after here in old |
4211 | * geometry. | |
f6705578 N |
4212 | */ |
4213 | here_new = mddev->reshape_position; | |
f416885e N |
4214 | if (sector_div(here_new, (mddev->chunk_size>>9)* |
4215 | (mddev->raid_disks - max_degraded))) { | |
4216 | printk(KERN_ERR "raid5: reshape_position not " | |
4217 | "on a stripe boundary\n"); | |
f6705578 N |
4218 | return -EINVAL; |
4219 | } | |
4220 | /* here_new is the stripe we will write to */ | |
4221 | here_old = mddev->reshape_position; | |
f416885e N |
4222 | sector_div(here_old, (mddev->chunk_size>>9)* |
4223 | (old_disks-max_degraded)); | |
4224 | /* here_old is the first stripe that we might need to read | |
4225 | * from */ | |
f6705578 N |
4226 | if (here_new >= here_old) { |
4227 | /* Reading from the same stripe as writing to - bad */ | |
f416885e N |
4228 | printk(KERN_ERR "raid5: reshape_position too early for " |
4229 | "auto-recovery - aborting.\n"); | |
f6705578 N |
4230 | return -EINVAL; |
4231 | } | |
4232 | printk(KERN_INFO "raid5: reshape will continue\n"); | |
4233 | /* OK, we should be able to continue; */ | |
4234 | } | |
4235 | ||
4236 | ||
b55e6bfc | 4237 | mddev->private = kzalloc(sizeof (raid5_conf_t), GFP_KERNEL); |
1da177e4 LT |
4238 | if ((conf = mddev->private) == NULL) |
4239 | goto abort; | |
f6705578 N |
4240 | if (mddev->reshape_position == MaxSector) { |
4241 | conf->previous_raid_disks = conf->raid_disks = mddev->raid_disks; | |
4242 | } else { | |
4243 | conf->raid_disks = mddev->raid_disks; | |
4244 | conf->previous_raid_disks = mddev->raid_disks - mddev->delta_disks; | |
4245 | } | |
4246 | ||
4247 | conf->disks = kzalloc(conf->raid_disks * sizeof(struct disk_info), | |
b55e6bfc N |
4248 | GFP_KERNEL); |
4249 | if (!conf->disks) | |
4250 | goto abort; | |
9ffae0cf | 4251 | |
1da177e4 LT |
4252 | conf->mddev = mddev; |
4253 | ||
fccddba0 | 4254 | if ((conf->stripe_hashtbl = kzalloc(PAGE_SIZE, GFP_KERNEL)) == NULL) |
1da177e4 | 4255 | goto abort; |
1da177e4 | 4256 | |
16a53ecc N |
4257 | if (mddev->level == 6) { |
4258 | conf->spare_page = alloc_page(GFP_KERNEL); | |
4259 | if (!conf->spare_page) | |
4260 | goto abort; | |
4261 | } | |
1da177e4 | 4262 | spin_lock_init(&conf->device_lock); |
e7e72bf6 | 4263 | mddev->queue->queue_lock = &conf->device_lock; |
1da177e4 LT |
4264 | init_waitqueue_head(&conf->wait_for_stripe); |
4265 | init_waitqueue_head(&conf->wait_for_overlap); | |
4266 | INIT_LIST_HEAD(&conf->handle_list); | |
8b3e6cdc | 4267 | INIT_LIST_HEAD(&conf->hold_list); |
1da177e4 | 4268 | INIT_LIST_HEAD(&conf->delayed_list); |
72626685 | 4269 | INIT_LIST_HEAD(&conf->bitmap_list); |
1da177e4 LT |
4270 | INIT_LIST_HEAD(&conf->inactive_list); |
4271 | atomic_set(&conf->active_stripes, 0); | |
4272 | atomic_set(&conf->preread_active_stripes, 0); | |
46031f9a | 4273 | atomic_set(&conf->active_aligned_reads, 0); |
8b3e6cdc | 4274 | conf->bypass_threshold = BYPASS_THRESHOLD; |
1da177e4 | 4275 | |
45b4233c | 4276 | pr_debug("raid5: run(%s) called.\n", mdname(mddev)); |
1da177e4 | 4277 | |
d089c6af | 4278 | rdev_for_each(rdev, tmp, mddev) { |
1da177e4 | 4279 | raid_disk = rdev->raid_disk; |
f6705578 | 4280 | if (raid_disk >= conf->raid_disks |
1da177e4 LT |
4281 | || raid_disk < 0) |
4282 | continue; | |
4283 | disk = conf->disks + raid_disk; | |
4284 | ||
4285 | disk->rdev = rdev; | |
4286 | ||
b2d444d7 | 4287 | if (test_bit(In_sync, &rdev->flags)) { |
1da177e4 LT |
4288 | char b[BDEVNAME_SIZE]; |
4289 | printk(KERN_INFO "raid5: device %s operational as raid" | |
4290 | " disk %d\n", bdevname(rdev->bdev,b), | |
4291 | raid_disk); | |
02c2de8c | 4292 | working_disks++; |
8c2e870a NB |
4293 | } else |
4294 | /* Cannot rely on bitmap to complete recovery */ | |
4295 | conf->fullsync = 1; | |
1da177e4 LT |
4296 | } |
4297 | ||
1da177e4 | 4298 | /* |
16a53ecc | 4299 | * 0 for a fully functional array, 1 or 2 for a degraded array. |
1da177e4 | 4300 | */ |
02c2de8c | 4301 | mddev->degraded = conf->raid_disks - working_disks; |
1da177e4 LT |
4302 | conf->mddev = mddev; |
4303 | conf->chunk_size = mddev->chunk_size; | |
4304 | conf->level = mddev->level; | |
16a53ecc N |
4305 | if (conf->level == 6) |
4306 | conf->max_degraded = 2; | |
4307 | else | |
4308 | conf->max_degraded = 1; | |
1da177e4 LT |
4309 | conf->algorithm = mddev->layout; |
4310 | conf->max_nr_stripes = NR_STRIPES; | |
f6705578 | 4311 | conf->expand_progress = mddev->reshape_position; |
1da177e4 LT |
4312 | |
4313 | /* device size must be a multiple of chunk size */ | |
4314 | mddev->size &= ~(mddev->chunk_size/1024 -1); | |
b1581566 | 4315 | mddev->resync_max_sectors = mddev->size << 1; |
1da177e4 | 4316 | |
16a53ecc N |
4317 | if (conf->level == 6 && conf->raid_disks < 4) { |
4318 | printk(KERN_ERR "raid6: not enough configured devices for %s (%d, minimum 4)\n", | |
4319 | mdname(mddev), conf->raid_disks); | |
4320 | goto abort; | |
4321 | } | |
1da177e4 LT |
4322 | if (!conf->chunk_size || conf->chunk_size % 4) { |
4323 | printk(KERN_ERR "raid5: invalid chunk size %d for %s\n", | |
4324 | conf->chunk_size, mdname(mddev)); | |
4325 | goto abort; | |
4326 | } | |
4327 | if (conf->algorithm > ALGORITHM_RIGHT_SYMMETRIC) { | |
4328 | printk(KERN_ERR | |
4329 | "raid5: unsupported parity algorithm %d for %s\n", | |
4330 | conf->algorithm, mdname(mddev)); | |
4331 | goto abort; | |
4332 | } | |
16a53ecc | 4333 | if (mddev->degraded > conf->max_degraded) { |
1da177e4 LT |
4334 | printk(KERN_ERR "raid5: not enough operational devices for %s" |
4335 | " (%d/%d failed)\n", | |
02c2de8c | 4336 | mdname(mddev), mddev->degraded, conf->raid_disks); |
1da177e4 LT |
4337 | goto abort; |
4338 | } | |
4339 | ||
16a53ecc | 4340 | if (mddev->degraded > 0 && |
1da177e4 | 4341 | mddev->recovery_cp != MaxSector) { |
6ff8d8ec N |
4342 | if (mddev->ok_start_degraded) |
4343 | printk(KERN_WARNING | |
4344 | "raid5: starting dirty degraded array: %s" | |
4345 | "- data corruption possible.\n", | |
4346 | mdname(mddev)); | |
4347 | else { | |
4348 | printk(KERN_ERR | |
4349 | "raid5: cannot start dirty degraded array for %s\n", | |
4350 | mdname(mddev)); | |
4351 | goto abort; | |
4352 | } | |
1da177e4 LT |
4353 | } |
4354 | ||
4355 | { | |
4356 | mddev->thread = md_register_thread(raid5d, mddev, "%s_raid5"); | |
4357 | if (!mddev->thread) { | |
4358 | printk(KERN_ERR | |
4359 | "raid5: couldn't allocate thread for %s\n", | |
4360 | mdname(mddev)); | |
4361 | goto abort; | |
4362 | } | |
4363 | } | |
5036805b | 4364 | memory = conf->max_nr_stripes * (sizeof(struct stripe_head) + |
1da177e4 LT |
4365 | conf->raid_disks * ((sizeof(struct bio) + PAGE_SIZE))) / 1024; |
4366 | if (grow_stripes(conf, conf->max_nr_stripes)) { | |
4367 | printk(KERN_ERR | |
4368 | "raid5: couldn't allocate %dkB for buffers\n", memory); | |
4369 | shrink_stripes(conf); | |
4370 | md_unregister_thread(mddev->thread); | |
4371 | goto abort; | |
4372 | } else | |
4373 | printk(KERN_INFO "raid5: allocated %dkB for %s\n", | |
4374 | memory, mdname(mddev)); | |
4375 | ||
4376 | if (mddev->degraded == 0) | |
4377 | printk("raid5: raid level %d set %s active with %d out of %d" | |
4378 | " devices, algorithm %d\n", conf->level, mdname(mddev), | |
4379 | mddev->raid_disks-mddev->degraded, mddev->raid_disks, | |
4380 | conf->algorithm); | |
4381 | else | |
4382 | printk(KERN_ALERT "raid5: raid level %d set %s active with %d" | |
4383 | " out of %d devices, algorithm %d\n", conf->level, | |
4384 | mdname(mddev), mddev->raid_disks - mddev->degraded, | |
4385 | mddev->raid_disks, conf->algorithm); | |
4386 | ||
4387 | print_raid5_conf(conf); | |
4388 | ||
f6705578 N |
4389 | if (conf->expand_progress != MaxSector) { |
4390 | printk("...ok start reshape thread\n"); | |
b578d55f | 4391 | conf->expand_lo = conf->expand_progress; |
f6705578 N |
4392 | atomic_set(&conf->reshape_stripes, 0); |
4393 | clear_bit(MD_RECOVERY_SYNC, &mddev->recovery); | |
4394 | clear_bit(MD_RECOVERY_CHECK, &mddev->recovery); | |
4395 | set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery); | |
4396 | set_bit(MD_RECOVERY_RUNNING, &mddev->recovery); | |
4397 | mddev->sync_thread = md_register_thread(md_do_sync, mddev, | |
4398 | "%s_reshape"); | |
f6705578 N |
4399 | } |
4400 | ||
1da177e4 | 4401 | /* read-ahead size must cover two whole stripes, which is |
16a53ecc | 4402 | * 2 * (datadisks) * chunksize where 'n' is the number of raid devices |
1da177e4 LT |
4403 | */ |
4404 | { | |
16a53ecc N |
4405 | int data_disks = conf->previous_raid_disks - conf->max_degraded; |
4406 | int stripe = data_disks * | |
8932c2e0 | 4407 | (mddev->chunk_size / PAGE_SIZE); |
1da177e4 LT |
4408 | if (mddev->queue->backing_dev_info.ra_pages < 2 * stripe) |
4409 | mddev->queue->backing_dev_info.ra_pages = 2 * stripe; | |
4410 | } | |
4411 | ||
4412 | /* Ok, everything is just fine now */ | |
5e55e2f5 N |
4413 | if (sysfs_create_group(&mddev->kobj, &raid5_attrs_group)) |
4414 | printk(KERN_WARNING | |
4415 | "raid5: failed to create sysfs attributes for %s\n", | |
4416 | mdname(mddev)); | |
7a5febe9 N |
4417 | |
4418 | mddev->queue->unplug_fn = raid5_unplug_device; | |
f022b2fd | 4419 | mddev->queue->backing_dev_info.congested_data = mddev; |
041ae52e | 4420 | mddev->queue->backing_dev_info.congested_fn = raid5_congested; |
f022b2fd | 4421 | |
16a53ecc N |
4422 | mddev->array_size = mddev->size * (conf->previous_raid_disks - |
4423 | conf->max_degraded); | |
7a5febe9 | 4424 | |
23032a0e RBJ |
4425 | blk_queue_merge_bvec(mddev->queue, raid5_mergeable_bvec); |
4426 | ||
1da177e4 LT |
4427 | return 0; |
4428 | abort: | |
4429 | if (conf) { | |
4430 | print_raid5_conf(conf); | |
16a53ecc | 4431 | safe_put_page(conf->spare_page); |
b55e6bfc | 4432 | kfree(conf->disks); |
fccddba0 | 4433 | kfree(conf->stripe_hashtbl); |
1da177e4 LT |
4434 | kfree(conf); |
4435 | } | |
4436 | mddev->private = NULL; | |
4437 | printk(KERN_ALERT "raid5: failed to run raid set %s\n", mdname(mddev)); | |
4438 | return -EIO; | |
4439 | } | |
4440 | ||
4441 | ||
4442 | ||
3f294f4f | 4443 | static int stop(mddev_t *mddev) |
1da177e4 LT |
4444 | { |
4445 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; | |
4446 | ||
4447 | md_unregister_thread(mddev->thread); | |
4448 | mddev->thread = NULL; | |
4449 | shrink_stripes(conf); | |
fccddba0 | 4450 | kfree(conf->stripe_hashtbl); |
041ae52e | 4451 | mddev->queue->backing_dev_info.congested_fn = NULL; |
1da177e4 | 4452 | blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/ |
007583c9 | 4453 | sysfs_remove_group(&mddev->kobj, &raid5_attrs_group); |
b55e6bfc | 4454 | kfree(conf->disks); |
96de1e66 | 4455 | kfree(conf); |
1da177e4 LT |
4456 | mddev->private = NULL; |
4457 | return 0; | |
4458 | } | |
4459 | ||
45b4233c | 4460 | #ifdef DEBUG |
16a53ecc | 4461 | static void print_sh (struct seq_file *seq, struct stripe_head *sh) |
1da177e4 LT |
4462 | { |
4463 | int i; | |
4464 | ||
16a53ecc N |
4465 | seq_printf(seq, "sh %llu, pd_idx %d, state %ld.\n", |
4466 | (unsigned long long)sh->sector, sh->pd_idx, sh->state); | |
4467 | seq_printf(seq, "sh %llu, count %d.\n", | |
4468 | (unsigned long long)sh->sector, atomic_read(&sh->count)); | |
4469 | seq_printf(seq, "sh %llu, ", (unsigned long long)sh->sector); | |
7ecaa1e6 | 4470 | for (i = 0; i < sh->disks; i++) { |
16a53ecc N |
4471 | seq_printf(seq, "(cache%d: %p %ld) ", |
4472 | i, sh->dev[i].page, sh->dev[i].flags); | |
1da177e4 | 4473 | } |
16a53ecc | 4474 | seq_printf(seq, "\n"); |
1da177e4 LT |
4475 | } |
4476 | ||
16a53ecc | 4477 | static void printall (struct seq_file *seq, raid5_conf_t *conf) |
1da177e4 LT |
4478 | { |
4479 | struct stripe_head *sh; | |
fccddba0 | 4480 | struct hlist_node *hn; |
1da177e4 LT |
4481 | int i; |
4482 | ||
4483 | spin_lock_irq(&conf->device_lock); | |
4484 | for (i = 0; i < NR_HASH; i++) { | |
fccddba0 | 4485 | hlist_for_each_entry(sh, hn, &conf->stripe_hashtbl[i], hash) { |
1da177e4 LT |
4486 | if (sh->raid_conf != conf) |
4487 | continue; | |
16a53ecc | 4488 | print_sh(seq, sh); |
1da177e4 LT |
4489 | } |
4490 | } | |
4491 | spin_unlock_irq(&conf->device_lock); | |
4492 | } | |
4493 | #endif | |
4494 | ||
4495 | static void status (struct seq_file *seq, mddev_t *mddev) | |
4496 | { | |
4497 | raid5_conf_t *conf = (raid5_conf_t *) mddev->private; | |
4498 | int i; | |
4499 | ||
4500 | seq_printf (seq, " level %d, %dk chunk, algorithm %d", mddev->level, mddev->chunk_size >> 10, mddev->layout); | |
02c2de8c | 4501 | seq_printf (seq, " [%d/%d] [", conf->raid_disks, conf->raid_disks - mddev->degraded); |
1da177e4 LT |
4502 | for (i = 0; i < conf->raid_disks; i++) |
4503 | seq_printf (seq, "%s", | |
4504 | conf->disks[i].rdev && | |
b2d444d7 | 4505 | test_bit(In_sync, &conf->disks[i].rdev->flags) ? "U" : "_"); |
1da177e4 | 4506 | seq_printf (seq, "]"); |
45b4233c | 4507 | #ifdef DEBUG |
16a53ecc N |
4508 | seq_printf (seq, "\n"); |
4509 | printall(seq, conf); | |
1da177e4 LT |
4510 | #endif |
4511 | } | |
4512 | ||
4513 | static void print_raid5_conf (raid5_conf_t *conf) | |
4514 | { | |
4515 | int i; | |
4516 | struct disk_info *tmp; | |
4517 | ||
4518 | printk("RAID5 conf printout:\n"); | |
4519 | if (!conf) { | |
4520 | printk("(conf==NULL)\n"); | |
4521 | return; | |
4522 | } | |
02c2de8c N |
4523 | printk(" --- rd:%d wd:%d\n", conf->raid_disks, |
4524 | conf->raid_disks - conf->mddev->degraded); | |
1da177e4 LT |
4525 | |
4526 | for (i = 0; i < conf->raid_disks; i++) { | |
4527 | char b[BDEVNAME_SIZE]; | |
4528 | tmp = conf->disks + i; | |
4529 | if (tmp->rdev) | |
4530 | printk(" disk %d, o:%d, dev:%s\n", | |
b2d444d7 | 4531 | i, !test_bit(Faulty, &tmp->rdev->flags), |
1da177e4 LT |
4532 | bdevname(tmp->rdev->bdev,b)); |
4533 | } | |
4534 | } | |
4535 | ||
4536 | static int raid5_spare_active(mddev_t *mddev) | |
4537 | { | |
4538 | int i; | |
4539 | raid5_conf_t *conf = mddev->private; | |
4540 | struct disk_info *tmp; | |
4541 | ||
4542 | for (i = 0; i < conf->raid_disks; i++) { | |
4543 | tmp = conf->disks + i; | |
4544 | if (tmp->rdev | |
b2d444d7 | 4545 | && !test_bit(Faulty, &tmp->rdev->flags) |
c04be0aa N |
4546 | && !test_and_set_bit(In_sync, &tmp->rdev->flags)) { |
4547 | unsigned long flags; | |
4548 | spin_lock_irqsave(&conf->device_lock, flags); | |
1da177e4 | 4549 | mddev->degraded--; |
c04be0aa | 4550 | spin_unlock_irqrestore(&conf->device_lock, flags); |
1da177e4 LT |
4551 | } |
4552 | } | |
4553 | print_raid5_conf(conf); | |
4554 | return 0; | |
4555 | } | |
4556 | ||
4557 | static int raid5_remove_disk(mddev_t *mddev, int number) | |
4558 | { | |
4559 | raid5_conf_t *conf = mddev->private; | |
4560 | int err = 0; | |
4561 | mdk_rdev_t *rdev; | |
4562 | struct disk_info *p = conf->disks + number; | |
4563 | ||
4564 | print_raid5_conf(conf); | |
4565 | rdev = p->rdev; | |
4566 | if (rdev) { | |
b2d444d7 | 4567 | if (test_bit(In_sync, &rdev->flags) || |
1da177e4 LT |
4568 | atomic_read(&rdev->nr_pending)) { |
4569 | err = -EBUSY; | |
4570 | goto abort; | |
4571 | } | |
dfc70645 N |
4572 | /* Only remove non-faulty devices if recovery |
4573 | * isn't possible. | |
4574 | */ | |
4575 | if (!test_bit(Faulty, &rdev->flags) && | |
4576 | mddev->degraded <= conf->max_degraded) { | |
4577 | err = -EBUSY; | |
4578 | goto abort; | |
4579 | } | |
1da177e4 | 4580 | p->rdev = NULL; |
fbd568a3 | 4581 | synchronize_rcu(); |
1da177e4 LT |
4582 | if (atomic_read(&rdev->nr_pending)) { |
4583 | /* lost the race, try later */ | |
4584 | err = -EBUSY; | |
4585 | p->rdev = rdev; | |
4586 | } | |
4587 | } | |
4588 | abort: | |
4589 | ||
4590 | print_raid5_conf(conf); | |
4591 | return err; | |
4592 | } | |
4593 | ||
4594 | static int raid5_add_disk(mddev_t *mddev, mdk_rdev_t *rdev) | |
4595 | { | |
4596 | raid5_conf_t *conf = mddev->private; | |
199050ea | 4597 | int err = -EEXIST; |
1da177e4 LT |
4598 | int disk; |
4599 | struct disk_info *p; | |
6c2fce2e NB |
4600 | int first = 0; |
4601 | int last = conf->raid_disks - 1; | |
1da177e4 | 4602 | |
16a53ecc | 4603 | if (mddev->degraded > conf->max_degraded) |
1da177e4 | 4604 | /* no point adding a device */ |
199050ea | 4605 | return -EINVAL; |
1da177e4 | 4606 | |
6c2fce2e NB |
4607 | if (rdev->raid_disk >= 0) |
4608 | first = last = rdev->raid_disk; | |
4609 | ||
1da177e4 | 4610 | /* |
16a53ecc N |
4611 | * find the disk ... but prefer rdev->saved_raid_disk |
4612 | * if possible. | |
1da177e4 | 4613 | */ |
16a53ecc | 4614 | if (rdev->saved_raid_disk >= 0 && |
6c2fce2e | 4615 | rdev->saved_raid_disk >= first && |
16a53ecc N |
4616 | conf->disks[rdev->saved_raid_disk].rdev == NULL) |
4617 | disk = rdev->saved_raid_disk; | |
4618 | else | |
6c2fce2e NB |
4619 | disk = first; |
4620 | for ( ; disk <= last ; disk++) | |
1da177e4 | 4621 | if ((p=conf->disks + disk)->rdev == NULL) { |
b2d444d7 | 4622 | clear_bit(In_sync, &rdev->flags); |
1da177e4 | 4623 | rdev->raid_disk = disk; |
199050ea | 4624 | err = 0; |
72626685 N |
4625 | if (rdev->saved_raid_disk != disk) |
4626 | conf->fullsync = 1; | |
d6065f7b | 4627 | rcu_assign_pointer(p->rdev, rdev); |
1da177e4 LT |
4628 | break; |
4629 | } | |
4630 | print_raid5_conf(conf); | |
199050ea | 4631 | return err; |
1da177e4 LT |
4632 | } |
4633 | ||
4634 | static int raid5_resize(mddev_t *mddev, sector_t sectors) | |
4635 | { | |
4636 | /* no resync is happening, and there is enough space | |
4637 | * on all devices, so we can resize. | |
4638 | * We need to make sure resync covers any new space. | |
4639 | * If the array is shrinking we should possibly wait until | |
4640 | * any io in the removed space completes, but it hardly seems | |
4641 | * worth it. | |
4642 | */ | |
16a53ecc N |
4643 | raid5_conf_t *conf = mddev_to_conf(mddev); |
4644 | ||
1da177e4 | 4645 | sectors &= ~((sector_t)mddev->chunk_size/512 - 1); |
16a53ecc | 4646 | mddev->array_size = (sectors * (mddev->raid_disks-conf->max_degraded))>>1; |
1da177e4 | 4647 | set_capacity(mddev->gendisk, mddev->array_size << 1); |
44ce6294 | 4648 | mddev->changed = 1; |
1da177e4 LT |
4649 | if (sectors/2 > mddev->size && mddev->recovery_cp == MaxSector) { |
4650 | mddev->recovery_cp = mddev->size << 1; | |
4651 | set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); | |
4652 | } | |
4653 | mddev->size = sectors /2; | |
4b5c7ae8 | 4654 | mddev->resync_max_sectors = sectors; |
1da177e4 LT |
4655 | return 0; |
4656 | } | |
4657 | ||
29269553 | 4658 | #ifdef CONFIG_MD_RAID5_RESHAPE |
63c70c4f | 4659 | static int raid5_check_reshape(mddev_t *mddev) |
29269553 N |
4660 | { |
4661 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4662 | int err; | |
29269553 | 4663 | |
63c70c4f N |
4664 | if (mddev->delta_disks < 0 || |
4665 | mddev->new_level != mddev->level) | |
4666 | return -EINVAL; /* Cannot shrink array or change level yet */ | |
4667 | if (mddev->delta_disks == 0) | |
29269553 N |
4668 | return 0; /* nothing to do */ |
4669 | ||
4670 | /* Can only proceed if there are plenty of stripe_heads. | |
4671 | * We need a minimum of one full stripe,, and for sensible progress | |
4672 | * it is best to have about 4 times that. | |
4673 | * If we require 4 times, then the default 256 4K stripe_heads will | |
4674 | * allow for chunk sizes up to 256K, which is probably OK. | |
4675 | * If the chunk size is greater, user-space should request more | |
4676 | * stripe_heads first. | |
4677 | */ | |
63c70c4f N |
4678 | if ((mddev->chunk_size / STRIPE_SIZE) * 4 > conf->max_nr_stripes || |
4679 | (mddev->new_chunk / STRIPE_SIZE) * 4 > conf->max_nr_stripes) { | |
29269553 N |
4680 | printk(KERN_WARNING "raid5: reshape: not enough stripes. Needed %lu\n", |
4681 | (mddev->chunk_size / STRIPE_SIZE)*4); | |
4682 | return -ENOSPC; | |
4683 | } | |
4684 | ||
63c70c4f N |
4685 | err = resize_stripes(conf, conf->raid_disks + mddev->delta_disks); |
4686 | if (err) | |
4687 | return err; | |
4688 | ||
b4c4c7b8 N |
4689 | if (mddev->degraded > conf->max_degraded) |
4690 | return -EINVAL; | |
63c70c4f N |
4691 | /* looks like we might be able to manage this */ |
4692 | return 0; | |
4693 | } | |
4694 | ||
4695 | static int raid5_start_reshape(mddev_t *mddev) | |
4696 | { | |
4697 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4698 | mdk_rdev_t *rdev; | |
4699 | struct list_head *rtmp; | |
4700 | int spares = 0; | |
4701 | int added_devices = 0; | |
c04be0aa | 4702 | unsigned long flags; |
63c70c4f | 4703 | |
f416885e | 4704 | if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) |
63c70c4f N |
4705 | return -EBUSY; |
4706 | ||
d089c6af | 4707 | rdev_for_each(rdev, rtmp, mddev) |
29269553 N |
4708 | if (rdev->raid_disk < 0 && |
4709 | !test_bit(Faulty, &rdev->flags)) | |
4710 | spares++; | |
63c70c4f | 4711 | |
f416885e | 4712 | if (spares - mddev->degraded < mddev->delta_disks - conf->max_degraded) |
29269553 N |
4713 | /* Not enough devices even to make a degraded array |
4714 | * of that size | |
4715 | */ | |
4716 | return -EINVAL; | |
4717 | ||
f6705578 | 4718 | atomic_set(&conf->reshape_stripes, 0); |
29269553 N |
4719 | spin_lock_irq(&conf->device_lock); |
4720 | conf->previous_raid_disks = conf->raid_disks; | |
63c70c4f | 4721 | conf->raid_disks += mddev->delta_disks; |
29269553 | 4722 | conf->expand_progress = 0; |
b578d55f | 4723 | conf->expand_lo = 0; |
29269553 N |
4724 | spin_unlock_irq(&conf->device_lock); |
4725 | ||
4726 | /* Add some new drives, as many as will fit. | |
4727 | * We know there are enough to make the newly sized array work. | |
4728 | */ | |
d089c6af | 4729 | rdev_for_each(rdev, rtmp, mddev) |
29269553 N |
4730 | if (rdev->raid_disk < 0 && |
4731 | !test_bit(Faulty, &rdev->flags)) { | |
199050ea | 4732 | if (raid5_add_disk(mddev, rdev) == 0) { |
29269553 N |
4733 | char nm[20]; |
4734 | set_bit(In_sync, &rdev->flags); | |
29269553 | 4735 | added_devices++; |
5fd6c1dc | 4736 | rdev->recovery_offset = 0; |
29269553 | 4737 | sprintf(nm, "rd%d", rdev->raid_disk); |
5e55e2f5 N |
4738 | if (sysfs_create_link(&mddev->kobj, |
4739 | &rdev->kobj, nm)) | |
4740 | printk(KERN_WARNING | |
4741 | "raid5: failed to create " | |
4742 | " link %s for %s\n", | |
4743 | nm, mdname(mddev)); | |
29269553 N |
4744 | } else |
4745 | break; | |
4746 | } | |
4747 | ||
c04be0aa | 4748 | spin_lock_irqsave(&conf->device_lock, flags); |
63c70c4f | 4749 | mddev->degraded = (conf->raid_disks - conf->previous_raid_disks) - added_devices; |
c04be0aa | 4750 | spin_unlock_irqrestore(&conf->device_lock, flags); |
63c70c4f | 4751 | mddev->raid_disks = conf->raid_disks; |
f6705578 | 4752 | mddev->reshape_position = 0; |
850b2b42 | 4753 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
f6705578 | 4754 | |
29269553 N |
4755 | clear_bit(MD_RECOVERY_SYNC, &mddev->recovery); |
4756 | clear_bit(MD_RECOVERY_CHECK, &mddev->recovery); | |
4757 | set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery); | |
4758 | set_bit(MD_RECOVERY_RUNNING, &mddev->recovery); | |
4759 | mddev->sync_thread = md_register_thread(md_do_sync, mddev, | |
4760 | "%s_reshape"); | |
4761 | if (!mddev->sync_thread) { | |
4762 | mddev->recovery = 0; | |
4763 | spin_lock_irq(&conf->device_lock); | |
4764 | mddev->raid_disks = conf->raid_disks = conf->previous_raid_disks; | |
4765 | conf->expand_progress = MaxSector; | |
4766 | spin_unlock_irq(&conf->device_lock); | |
4767 | return -EAGAIN; | |
4768 | } | |
4769 | md_wakeup_thread(mddev->sync_thread); | |
4770 | md_new_event(mddev); | |
4771 | return 0; | |
4772 | } | |
4773 | #endif | |
4774 | ||
4775 | static void end_reshape(raid5_conf_t *conf) | |
4776 | { | |
4777 | struct block_device *bdev; | |
4778 | ||
f6705578 | 4779 | if (!test_bit(MD_RECOVERY_INTR, &conf->mddev->recovery)) { |
f416885e N |
4780 | conf->mddev->array_size = conf->mddev->size * |
4781 | (conf->raid_disks - conf->max_degraded); | |
f6705578 | 4782 | set_capacity(conf->mddev->gendisk, conf->mddev->array_size << 1); |
44ce6294 | 4783 | conf->mddev->changed = 1; |
f6705578 N |
4784 | |
4785 | bdev = bdget_disk(conf->mddev->gendisk, 0); | |
4786 | if (bdev) { | |
4787 | mutex_lock(&bdev->bd_inode->i_mutex); | |
0692c6b1 | 4788 | i_size_write(bdev->bd_inode, (loff_t)conf->mddev->array_size << 10); |
f6705578 N |
4789 | mutex_unlock(&bdev->bd_inode->i_mutex); |
4790 | bdput(bdev); | |
4791 | } | |
4792 | spin_lock_irq(&conf->device_lock); | |
4793 | conf->expand_progress = MaxSector; | |
4794 | spin_unlock_irq(&conf->device_lock); | |
4795 | conf->mddev->reshape_position = MaxSector; | |
16a53ecc N |
4796 | |
4797 | /* read-ahead size must cover two whole stripes, which is | |
4798 | * 2 * (datadisks) * chunksize where 'n' is the number of raid devices | |
4799 | */ | |
4800 | { | |
4801 | int data_disks = conf->previous_raid_disks - conf->max_degraded; | |
4802 | int stripe = data_disks * | |
4803 | (conf->mddev->chunk_size / PAGE_SIZE); | |
4804 | if (conf->mddev->queue->backing_dev_info.ra_pages < 2 * stripe) | |
4805 | conf->mddev->queue->backing_dev_info.ra_pages = 2 * stripe; | |
4806 | } | |
29269553 | 4807 | } |
29269553 N |
4808 | } |
4809 | ||
72626685 N |
4810 | static void raid5_quiesce(mddev_t *mddev, int state) |
4811 | { | |
4812 | raid5_conf_t *conf = mddev_to_conf(mddev); | |
4813 | ||
4814 | switch(state) { | |
e464eafd N |
4815 | case 2: /* resume for a suspend */ |
4816 | wake_up(&conf->wait_for_overlap); | |
4817 | break; | |
4818 | ||
72626685 N |
4819 | case 1: /* stop all writes */ |
4820 | spin_lock_irq(&conf->device_lock); | |
4821 | conf->quiesce = 1; | |
4822 | wait_event_lock_irq(conf->wait_for_stripe, | |
46031f9a RBJ |
4823 | atomic_read(&conf->active_stripes) == 0 && |
4824 | atomic_read(&conf->active_aligned_reads) == 0, | |
72626685 N |
4825 | conf->device_lock, /* nothing */); |
4826 | spin_unlock_irq(&conf->device_lock); | |
4827 | break; | |
4828 | ||
4829 | case 0: /* re-enable writes */ | |
4830 | spin_lock_irq(&conf->device_lock); | |
4831 | conf->quiesce = 0; | |
4832 | wake_up(&conf->wait_for_stripe); | |
e464eafd | 4833 | wake_up(&conf->wait_for_overlap); |
72626685 N |
4834 | spin_unlock_irq(&conf->device_lock); |
4835 | break; | |
4836 | } | |
72626685 | 4837 | } |
b15c2e57 | 4838 | |
16a53ecc N |
4839 | static struct mdk_personality raid6_personality = |
4840 | { | |
4841 | .name = "raid6", | |
4842 | .level = 6, | |
4843 | .owner = THIS_MODULE, | |
4844 | .make_request = make_request, | |
4845 | .run = run, | |
4846 | .stop = stop, | |
4847 | .status = status, | |
4848 | .error_handler = error, | |
4849 | .hot_add_disk = raid5_add_disk, | |
4850 | .hot_remove_disk= raid5_remove_disk, | |
4851 | .spare_active = raid5_spare_active, | |
4852 | .sync_request = sync_request, | |
4853 | .resize = raid5_resize, | |
f416885e N |
4854 | #ifdef CONFIG_MD_RAID5_RESHAPE |
4855 | .check_reshape = raid5_check_reshape, | |
4856 | .start_reshape = raid5_start_reshape, | |
4857 | #endif | |
16a53ecc N |
4858 | .quiesce = raid5_quiesce, |
4859 | }; | |
2604b703 | 4860 | static struct mdk_personality raid5_personality = |
1da177e4 LT |
4861 | { |
4862 | .name = "raid5", | |
2604b703 | 4863 | .level = 5, |
1da177e4 LT |
4864 | .owner = THIS_MODULE, |
4865 | .make_request = make_request, | |
4866 | .run = run, | |
4867 | .stop = stop, | |
4868 | .status = status, | |
4869 | .error_handler = error, | |
4870 | .hot_add_disk = raid5_add_disk, | |
4871 | .hot_remove_disk= raid5_remove_disk, | |
4872 | .spare_active = raid5_spare_active, | |
4873 | .sync_request = sync_request, | |
4874 | .resize = raid5_resize, | |
29269553 | 4875 | #ifdef CONFIG_MD_RAID5_RESHAPE |
63c70c4f N |
4876 | .check_reshape = raid5_check_reshape, |
4877 | .start_reshape = raid5_start_reshape, | |
29269553 | 4878 | #endif |
72626685 | 4879 | .quiesce = raid5_quiesce, |
1da177e4 LT |
4880 | }; |
4881 | ||
2604b703 | 4882 | static struct mdk_personality raid4_personality = |
1da177e4 | 4883 | { |
2604b703 N |
4884 | .name = "raid4", |
4885 | .level = 4, | |
4886 | .owner = THIS_MODULE, | |
4887 | .make_request = make_request, | |
4888 | .run = run, | |
4889 | .stop = stop, | |
4890 | .status = status, | |
4891 | .error_handler = error, | |
4892 | .hot_add_disk = raid5_add_disk, | |
4893 | .hot_remove_disk= raid5_remove_disk, | |
4894 | .spare_active = raid5_spare_active, | |
4895 | .sync_request = sync_request, | |
4896 | .resize = raid5_resize, | |
3d37890b N |
4897 | #ifdef CONFIG_MD_RAID5_RESHAPE |
4898 | .check_reshape = raid5_check_reshape, | |
4899 | .start_reshape = raid5_start_reshape, | |
4900 | #endif | |
2604b703 N |
4901 | .quiesce = raid5_quiesce, |
4902 | }; | |
4903 | ||
4904 | static int __init raid5_init(void) | |
4905 | { | |
16a53ecc N |
4906 | int e; |
4907 | ||
4908 | e = raid6_select_algo(); | |
4909 | if ( e ) | |
4910 | return e; | |
4911 | register_md_personality(&raid6_personality); | |
2604b703 N |
4912 | register_md_personality(&raid5_personality); |
4913 | register_md_personality(&raid4_personality); | |
4914 | return 0; | |
1da177e4 LT |
4915 | } |
4916 | ||
2604b703 | 4917 | static void raid5_exit(void) |
1da177e4 | 4918 | { |
16a53ecc | 4919 | unregister_md_personality(&raid6_personality); |
2604b703 N |
4920 | unregister_md_personality(&raid5_personality); |
4921 | unregister_md_personality(&raid4_personality); | |
1da177e4 LT |
4922 | } |
4923 | ||
4924 | module_init(raid5_init); | |
4925 | module_exit(raid5_exit); | |
4926 | MODULE_LICENSE("GPL"); | |
4927 | MODULE_ALIAS("md-personality-4"); /* RAID5 */ | |
d9d166c2 N |
4928 | MODULE_ALIAS("md-raid5"); |
4929 | MODULE_ALIAS("md-raid4"); | |
2604b703 N |
4930 | MODULE_ALIAS("md-level-5"); |
4931 | MODULE_ALIAS("md-level-4"); | |
16a53ecc N |
4932 | MODULE_ALIAS("md-personality-8"); /* RAID6 */ |
4933 | MODULE_ALIAS("md-raid6"); | |
4934 | MODULE_ALIAS("md-level-6"); | |
4935 | ||
4936 | /* This used to be two separate modules, they were: */ | |
4937 | MODULE_ALIAS("raid5"); | |
4938 | MODULE_ALIAS("raid6"); |