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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * raid1.c : Multiple Devices driver for Linux | |
3 | * | |
4 | * Copyright (C) 1999, 2000, 2001 Ingo Molnar, Red Hat | |
5 | * | |
6 | * Copyright (C) 1996, 1997, 1998 Ingo Molnar, Miguel de Icaza, Gadi Oxman | |
7 | * | |
8 | * RAID-1 management functions. | |
9 | * | |
10 | * Better read-balancing code written by Mika Kuoppala <miku@iki.fi>, 2000 | |
11 | * | |
96de0e25 | 12 | * Fixes to reconstruction by Jakob Østergaard" <jakob@ostenfeld.dk> |
1da177e4 LT |
13 | * Various fixes by Neil Brown <neilb@cse.unsw.edu.au> |
14 | * | |
191ea9b2 N |
15 | * Changes by Peter T. Breuer <ptb@it.uc3m.es> 31/1/2003 to support |
16 | * bitmapped intelligence in resync: | |
17 | * | |
18 | * - bitmap marked during normal i/o | |
19 | * - bitmap used to skip nondirty blocks during sync | |
20 | * | |
21 | * Additions to bitmap code, (C) 2003-2004 Paul Clements, SteelEye Technology: | |
22 | * - persistent bitmap code | |
23 | * | |
1da177e4 LT |
24 | * This program is free software; you can redistribute it and/or modify |
25 | * it under the terms of the GNU General Public License as published by | |
26 | * the Free Software Foundation; either version 2, or (at your option) | |
27 | * any later version. | |
28 | * | |
29 | * You should have received a copy of the GNU General Public License | |
30 | * (for example /usr/src/linux/COPYING); if not, write to the Free | |
31 | * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | |
32 | */ | |
33 | ||
5a0e3ad6 | 34 | #include <linux/slab.h> |
25570727 | 35 | #include <linux/delay.h> |
bff61975 | 36 | #include <linux/blkdev.h> |
bff61975 | 37 | #include <linux/seq_file.h> |
43b2e5d8 | 38 | #include "md.h" |
ef740c37 CH |
39 | #include "raid1.h" |
40 | #include "bitmap.h" | |
191ea9b2 N |
41 | |
42 | #define DEBUG 0 | |
43 | #if DEBUG | |
44 | #define PRINTK(x...) printk(x) | |
45 | #else | |
46 | #define PRINTK(x...) | |
47 | #endif | |
1da177e4 LT |
48 | |
49 | /* | |
50 | * Number of guaranteed r1bios in case of extreme VM load: | |
51 | */ | |
52 | #define NR_RAID1_BIOS 256 | |
53 | ||
1da177e4 LT |
54 | |
55 | static void unplug_slaves(mddev_t *mddev); | |
56 | ||
17999be4 N |
57 | static void allow_barrier(conf_t *conf); |
58 | static void lower_barrier(conf_t *conf); | |
1da177e4 | 59 | |
dd0fc66f | 60 | static void * r1bio_pool_alloc(gfp_t gfp_flags, void *data) |
1da177e4 LT |
61 | { |
62 | struct pool_info *pi = data; | |
63 | r1bio_t *r1_bio; | |
64 | int size = offsetof(r1bio_t, bios[pi->raid_disks]); | |
65 | ||
66 | /* allocate a r1bio with room for raid_disks entries in the bios array */ | |
9ffae0cf | 67 | r1_bio = kzalloc(size, gfp_flags); |
ed9bfdf1 | 68 | if (!r1_bio && pi->mddev) |
1da177e4 LT |
69 | unplug_slaves(pi->mddev); |
70 | ||
71 | return r1_bio; | |
72 | } | |
73 | ||
74 | static void r1bio_pool_free(void *r1_bio, void *data) | |
75 | { | |
76 | kfree(r1_bio); | |
77 | } | |
78 | ||
79 | #define RESYNC_BLOCK_SIZE (64*1024) | |
80 | //#define RESYNC_BLOCK_SIZE PAGE_SIZE | |
81 | #define RESYNC_SECTORS (RESYNC_BLOCK_SIZE >> 9) | |
82 | #define RESYNC_PAGES ((RESYNC_BLOCK_SIZE + PAGE_SIZE-1) / PAGE_SIZE) | |
83 | #define RESYNC_WINDOW (2048*1024) | |
84 | ||
dd0fc66f | 85 | static void * r1buf_pool_alloc(gfp_t gfp_flags, void *data) |
1da177e4 LT |
86 | { |
87 | struct pool_info *pi = data; | |
88 | struct page *page; | |
89 | r1bio_t *r1_bio; | |
90 | struct bio *bio; | |
91 | int i, j; | |
92 | ||
93 | r1_bio = r1bio_pool_alloc(gfp_flags, pi); | |
94 | if (!r1_bio) { | |
95 | unplug_slaves(pi->mddev); | |
96 | return NULL; | |
97 | } | |
98 | ||
99 | /* | |
100 | * Allocate bios : 1 for reading, n-1 for writing | |
101 | */ | |
102 | for (j = pi->raid_disks ; j-- ; ) { | |
6746557f | 103 | bio = bio_kmalloc(gfp_flags, RESYNC_PAGES); |
1da177e4 LT |
104 | if (!bio) |
105 | goto out_free_bio; | |
106 | r1_bio->bios[j] = bio; | |
107 | } | |
108 | /* | |
109 | * Allocate RESYNC_PAGES data pages and attach them to | |
d11c171e N |
110 | * the first bio. |
111 | * If this is a user-requested check/repair, allocate | |
112 | * RESYNC_PAGES for each bio. | |
1da177e4 | 113 | */ |
d11c171e N |
114 | if (test_bit(MD_RECOVERY_REQUESTED, &pi->mddev->recovery)) |
115 | j = pi->raid_disks; | |
116 | else | |
117 | j = 1; | |
118 | while(j--) { | |
119 | bio = r1_bio->bios[j]; | |
120 | for (i = 0; i < RESYNC_PAGES; i++) { | |
121 | page = alloc_page(gfp_flags); | |
122 | if (unlikely(!page)) | |
123 | goto out_free_pages; | |
124 | ||
125 | bio->bi_io_vec[i].bv_page = page; | |
303a0e11 | 126 | bio->bi_vcnt = i+1; |
d11c171e N |
127 | } |
128 | } | |
129 | /* If not user-requests, copy the page pointers to all bios */ | |
130 | if (!test_bit(MD_RECOVERY_REQUESTED, &pi->mddev->recovery)) { | |
131 | for (i=0; i<RESYNC_PAGES ; i++) | |
132 | for (j=1; j<pi->raid_disks; j++) | |
133 | r1_bio->bios[j]->bi_io_vec[i].bv_page = | |
134 | r1_bio->bios[0]->bi_io_vec[i].bv_page; | |
1da177e4 LT |
135 | } |
136 | ||
137 | r1_bio->master_bio = NULL; | |
138 | ||
139 | return r1_bio; | |
140 | ||
141 | out_free_pages: | |
303a0e11 N |
142 | for (j=0 ; j < pi->raid_disks; j++) |
143 | for (i=0; i < r1_bio->bios[j]->bi_vcnt ; i++) | |
144 | put_page(r1_bio->bios[j]->bi_io_vec[i].bv_page); | |
d11c171e | 145 | j = -1; |
1da177e4 LT |
146 | out_free_bio: |
147 | while ( ++j < pi->raid_disks ) | |
148 | bio_put(r1_bio->bios[j]); | |
149 | r1bio_pool_free(r1_bio, data); | |
150 | return NULL; | |
151 | } | |
152 | ||
153 | static void r1buf_pool_free(void *__r1_bio, void *data) | |
154 | { | |
155 | struct pool_info *pi = data; | |
d11c171e | 156 | int i,j; |
1da177e4 | 157 | r1bio_t *r1bio = __r1_bio; |
1da177e4 | 158 | |
d11c171e N |
159 | for (i = 0; i < RESYNC_PAGES; i++) |
160 | for (j = pi->raid_disks; j-- ;) { | |
161 | if (j == 0 || | |
162 | r1bio->bios[j]->bi_io_vec[i].bv_page != | |
163 | r1bio->bios[0]->bi_io_vec[i].bv_page) | |
1345b1d8 | 164 | safe_put_page(r1bio->bios[j]->bi_io_vec[i].bv_page); |
d11c171e | 165 | } |
1da177e4 LT |
166 | for (i=0 ; i < pi->raid_disks; i++) |
167 | bio_put(r1bio->bios[i]); | |
168 | ||
169 | r1bio_pool_free(r1bio, data); | |
170 | } | |
171 | ||
172 | static void put_all_bios(conf_t *conf, r1bio_t *r1_bio) | |
173 | { | |
174 | int i; | |
175 | ||
176 | for (i = 0; i < conf->raid_disks; i++) { | |
177 | struct bio **bio = r1_bio->bios + i; | |
cf30a473 | 178 | if (*bio && *bio != IO_BLOCKED) |
1da177e4 LT |
179 | bio_put(*bio); |
180 | *bio = NULL; | |
181 | } | |
182 | } | |
183 | ||
858119e1 | 184 | static void free_r1bio(r1bio_t *r1_bio) |
1da177e4 | 185 | { |
070ec55d | 186 | conf_t *conf = r1_bio->mddev->private; |
1da177e4 LT |
187 | |
188 | /* | |
189 | * Wake up any possible resync thread that waits for the device | |
190 | * to go idle. | |
191 | */ | |
17999be4 | 192 | allow_barrier(conf); |
1da177e4 LT |
193 | |
194 | put_all_bios(conf, r1_bio); | |
195 | mempool_free(r1_bio, conf->r1bio_pool); | |
196 | } | |
197 | ||
858119e1 | 198 | static void put_buf(r1bio_t *r1_bio) |
1da177e4 | 199 | { |
070ec55d | 200 | conf_t *conf = r1_bio->mddev->private; |
3e198f78 N |
201 | int i; |
202 | ||
203 | for (i=0; i<conf->raid_disks; i++) { | |
204 | struct bio *bio = r1_bio->bios[i]; | |
205 | if (bio->bi_end_io) | |
206 | rdev_dec_pending(conf->mirrors[i].rdev, r1_bio->mddev); | |
207 | } | |
1da177e4 LT |
208 | |
209 | mempool_free(r1_bio, conf->r1buf_pool); | |
210 | ||
17999be4 | 211 | lower_barrier(conf); |
1da177e4 LT |
212 | } |
213 | ||
214 | static void reschedule_retry(r1bio_t *r1_bio) | |
215 | { | |
216 | unsigned long flags; | |
217 | mddev_t *mddev = r1_bio->mddev; | |
070ec55d | 218 | conf_t *conf = mddev->private; |
1da177e4 LT |
219 | |
220 | spin_lock_irqsave(&conf->device_lock, flags); | |
221 | list_add(&r1_bio->retry_list, &conf->retry_list); | |
ddaf22ab | 222 | conf->nr_queued ++; |
1da177e4 LT |
223 | spin_unlock_irqrestore(&conf->device_lock, flags); |
224 | ||
17999be4 | 225 | wake_up(&conf->wait_barrier); |
1da177e4 LT |
226 | md_wakeup_thread(mddev->thread); |
227 | } | |
228 | ||
229 | /* | |
230 | * raid_end_bio_io() is called when we have finished servicing a mirrored | |
231 | * operation and are ready to return a success/failure code to the buffer | |
232 | * cache layer. | |
233 | */ | |
234 | static void raid_end_bio_io(r1bio_t *r1_bio) | |
235 | { | |
236 | struct bio *bio = r1_bio->master_bio; | |
237 | ||
4b6d287f N |
238 | /* if nobody has done the final endio yet, do it now */ |
239 | if (!test_and_set_bit(R1BIO_Returned, &r1_bio->state)) { | |
240 | PRINTK(KERN_DEBUG "raid1: sync end %s on sectors %llu-%llu\n", | |
241 | (bio_data_dir(bio) == WRITE) ? "write" : "read", | |
242 | (unsigned long long) bio->bi_sector, | |
243 | (unsigned long long) bio->bi_sector + | |
244 | (bio->bi_size >> 9) - 1); | |
245 | ||
6712ecf8 | 246 | bio_endio(bio, |
4b6d287f N |
247 | test_bit(R1BIO_Uptodate, &r1_bio->state) ? 0 : -EIO); |
248 | } | |
1da177e4 LT |
249 | free_r1bio(r1_bio); |
250 | } | |
251 | ||
252 | /* | |
253 | * Update disk head position estimator based on IRQ completion info. | |
254 | */ | |
255 | static inline void update_head_pos(int disk, r1bio_t *r1_bio) | |
256 | { | |
070ec55d | 257 | conf_t *conf = r1_bio->mddev->private; |
1da177e4 LT |
258 | |
259 | conf->mirrors[disk].head_position = | |
260 | r1_bio->sector + (r1_bio->sectors); | |
261 | } | |
262 | ||
6712ecf8 | 263 | static void raid1_end_read_request(struct bio *bio, int error) |
1da177e4 LT |
264 | { |
265 | int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
7b92813c | 266 | r1bio_t *r1_bio = bio->bi_private; |
1da177e4 | 267 | int mirror; |
070ec55d | 268 | conf_t *conf = r1_bio->mddev->private; |
1da177e4 | 269 | |
1da177e4 LT |
270 | mirror = r1_bio->read_disk; |
271 | /* | |
272 | * this branch is our 'one mirror IO has finished' event handler: | |
273 | */ | |
ddaf22ab N |
274 | update_head_pos(mirror, r1_bio); |
275 | ||
dd00a99e N |
276 | if (uptodate) |
277 | set_bit(R1BIO_Uptodate, &r1_bio->state); | |
278 | else { | |
279 | /* If all other devices have failed, we want to return | |
280 | * the error upwards rather than fail the last device. | |
281 | * Here we redefine "uptodate" to mean "Don't want to retry" | |
1da177e4 | 282 | */ |
dd00a99e N |
283 | unsigned long flags; |
284 | spin_lock_irqsave(&conf->device_lock, flags); | |
285 | if (r1_bio->mddev->degraded == conf->raid_disks || | |
286 | (r1_bio->mddev->degraded == conf->raid_disks-1 && | |
287 | !test_bit(Faulty, &conf->mirrors[mirror].rdev->flags))) | |
288 | uptodate = 1; | |
289 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
290 | } | |
1da177e4 | 291 | |
dd00a99e | 292 | if (uptodate) |
1da177e4 | 293 | raid_end_bio_io(r1_bio); |
dd00a99e | 294 | else { |
1da177e4 LT |
295 | /* |
296 | * oops, read error: | |
297 | */ | |
298 | char b[BDEVNAME_SIZE]; | |
299 | if (printk_ratelimit()) | |
9dd1e2fa N |
300 | printk(KERN_ERR "md/raid1:%s: %s: rescheduling sector %llu\n", |
301 | mdname(conf->mddev), | |
1da177e4 LT |
302 | bdevname(conf->mirrors[mirror].rdev->bdev,b), (unsigned long long)r1_bio->sector); |
303 | reschedule_retry(r1_bio); | |
304 | } | |
305 | ||
306 | rdev_dec_pending(conf->mirrors[mirror].rdev, conf->mddev); | |
1da177e4 LT |
307 | } |
308 | ||
4e78064f N |
309 | static void r1_bio_write_done(r1bio_t *r1_bio, int vcnt, struct bio_vec *bv, |
310 | int behind) | |
311 | { | |
312 | if (atomic_dec_and_test(&r1_bio->remaining)) | |
313 | { | |
314 | /* it really is the end of this request */ | |
315 | if (test_bit(R1BIO_BehindIO, &r1_bio->state)) { | |
316 | /* free extra copy of the data pages */ | |
317 | int i = vcnt; | |
318 | while (i--) | |
319 | safe_put_page(bv[i].bv_page); | |
320 | } | |
321 | /* clear the bitmap if all writes complete successfully */ | |
322 | bitmap_endwrite(r1_bio->mddev->bitmap, r1_bio->sector, | |
323 | r1_bio->sectors, | |
324 | !test_bit(R1BIO_Degraded, &r1_bio->state), | |
325 | behind); | |
326 | md_write_end(r1_bio->mddev); | |
327 | raid_end_bio_io(r1_bio); | |
328 | } | |
329 | } | |
330 | ||
6712ecf8 | 331 | static void raid1_end_write_request(struct bio *bio, int error) |
1da177e4 LT |
332 | { |
333 | int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
7b92813c | 334 | r1bio_t *r1_bio = bio->bi_private; |
a9701a30 | 335 | int mirror, behind = test_bit(R1BIO_BehindIO, &r1_bio->state); |
070ec55d | 336 | conf_t *conf = r1_bio->mddev->private; |
04b857f7 | 337 | struct bio *to_put = NULL; |
1da177e4 | 338 | |
1da177e4 LT |
339 | |
340 | for (mirror = 0; mirror < conf->raid_disks; mirror++) | |
341 | if (r1_bio->bios[mirror] == bio) | |
342 | break; | |
343 | ||
e9c7469b TH |
344 | /* |
345 | * 'one mirror IO has finished' event handler: | |
346 | */ | |
347 | r1_bio->bios[mirror] = NULL; | |
348 | to_put = bio; | |
349 | if (!uptodate) { | |
350 | md_error(r1_bio->mddev, conf->mirrors[mirror].rdev); | |
351 | /* an I/O failed, we can't clear the bitmap */ | |
352 | set_bit(R1BIO_Degraded, &r1_bio->state); | |
353 | } else | |
1da177e4 | 354 | /* |
e9c7469b TH |
355 | * Set R1BIO_Uptodate in our master bio, so that we |
356 | * will return a good error code for to the higher | |
357 | * levels even if IO on some other mirrored buffer | |
358 | * fails. | |
359 | * | |
360 | * The 'master' represents the composite IO operation | |
361 | * to user-side. So if something waits for IO, then it | |
362 | * will wait for the 'master' bio. | |
1da177e4 | 363 | */ |
e9c7469b TH |
364 | set_bit(R1BIO_Uptodate, &r1_bio->state); |
365 | ||
366 | update_head_pos(mirror, r1_bio); | |
367 | ||
368 | if (behind) { | |
369 | if (test_bit(WriteMostly, &conf->mirrors[mirror].rdev->flags)) | |
370 | atomic_dec(&r1_bio->behind_remaining); | |
371 | ||
372 | /* | |
373 | * In behind mode, we ACK the master bio once the I/O | |
374 | * has safely reached all non-writemostly | |
375 | * disks. Setting the Returned bit ensures that this | |
376 | * gets done only once -- we don't ever want to return | |
377 | * -EIO here, instead we'll wait | |
378 | */ | |
379 | if (atomic_read(&r1_bio->behind_remaining) >= (atomic_read(&r1_bio->remaining)-1) && | |
380 | test_bit(R1BIO_Uptodate, &r1_bio->state)) { | |
381 | /* Maybe we can return now */ | |
382 | if (!test_and_set_bit(R1BIO_Returned, &r1_bio->state)) { | |
383 | struct bio *mbio = r1_bio->master_bio; | |
384 | PRINTK(KERN_DEBUG "raid1: behind end write sectors %llu-%llu\n", | |
385 | (unsigned long long) mbio->bi_sector, | |
386 | (unsigned long long) mbio->bi_sector + | |
387 | (mbio->bi_size >> 9) - 1); | |
388 | bio_endio(mbio, 0); | |
4b6d287f N |
389 | } |
390 | } | |
391 | } | |
e9c7469b TH |
392 | rdev_dec_pending(conf->mirrors[mirror].rdev, conf->mddev); |
393 | ||
1da177e4 | 394 | /* |
1da177e4 LT |
395 | * Let's see if all mirrored write operations have finished |
396 | * already. | |
397 | */ | |
4e78064f | 398 | r1_bio_write_done(r1_bio, bio->bi_vcnt, bio->bi_io_vec, behind); |
c70810b3 | 399 | |
04b857f7 N |
400 | if (to_put) |
401 | bio_put(to_put); | |
1da177e4 LT |
402 | } |
403 | ||
404 | ||
405 | /* | |
406 | * This routine returns the disk from which the requested read should | |
407 | * be done. There is a per-array 'next expected sequential IO' sector | |
408 | * number - if this matches on the next IO then we use the last disk. | |
409 | * There is also a per-disk 'last know head position' sector that is | |
410 | * maintained from IRQ contexts, both the normal and the resync IO | |
411 | * completion handlers update this position correctly. If there is no | |
412 | * perfect sequential match then we pick the disk whose head is closest. | |
413 | * | |
414 | * If there are 2 mirrors in the same 2 devices, performance degrades | |
415 | * because position is mirror, not device based. | |
416 | * | |
417 | * The rdev for the device selected will have nr_pending incremented. | |
418 | */ | |
419 | static int read_balance(conf_t *conf, r1bio_t *r1_bio) | |
420 | { | |
af3a2cd6 | 421 | const sector_t this_sector = r1_bio->sector; |
1da177e4 | 422 | int new_disk = conf->last_used, disk = new_disk; |
8ddf9efe | 423 | int wonly_disk = -1; |
1da177e4 LT |
424 | const int sectors = r1_bio->sectors; |
425 | sector_t new_distance, current_distance; | |
8ddf9efe | 426 | mdk_rdev_t *rdev; |
1da177e4 LT |
427 | |
428 | rcu_read_lock(); | |
429 | /* | |
8ddf9efe | 430 | * Check if we can balance. We can balance on the whole |
1da177e4 LT |
431 | * device if no resync is going on, or below the resync window. |
432 | * We take the first readable disk when above the resync window. | |
433 | */ | |
434 | retry: | |
435 | if (conf->mddev->recovery_cp < MaxSector && | |
436 | (this_sector + sectors >= conf->next_resync)) { | |
af3a2cd6 | 437 | /* Choose the first operational device, for consistancy */ |
1da177e4 LT |
438 | new_disk = 0; |
439 | ||
d6065f7b | 440 | for (rdev = rcu_dereference(conf->mirrors[new_disk].rdev); |
cf30a473 | 441 | r1_bio->bios[new_disk] == IO_BLOCKED || |
b2d444d7 | 442 | !rdev || !test_bit(In_sync, &rdev->flags) |
8ddf9efe | 443 | || test_bit(WriteMostly, &rdev->flags); |
d6065f7b | 444 | rdev = rcu_dereference(conf->mirrors[++new_disk].rdev)) { |
8ddf9efe | 445 | |
cf30a473 N |
446 | if (rdev && test_bit(In_sync, &rdev->flags) && |
447 | r1_bio->bios[new_disk] != IO_BLOCKED) | |
8ddf9efe N |
448 | wonly_disk = new_disk; |
449 | ||
450 | if (new_disk == conf->raid_disks - 1) { | |
451 | new_disk = wonly_disk; | |
1da177e4 LT |
452 | break; |
453 | } | |
454 | } | |
455 | goto rb_out; | |
456 | } | |
457 | ||
458 | ||
459 | /* make sure the disk is operational */ | |
d6065f7b | 460 | for (rdev = rcu_dereference(conf->mirrors[new_disk].rdev); |
cf30a473 | 461 | r1_bio->bios[new_disk] == IO_BLOCKED || |
b2d444d7 | 462 | !rdev || !test_bit(In_sync, &rdev->flags) || |
8ddf9efe | 463 | test_bit(WriteMostly, &rdev->flags); |
d6065f7b | 464 | rdev = rcu_dereference(conf->mirrors[new_disk].rdev)) { |
8ddf9efe | 465 | |
cf30a473 N |
466 | if (rdev && test_bit(In_sync, &rdev->flags) && |
467 | r1_bio->bios[new_disk] != IO_BLOCKED) | |
8ddf9efe N |
468 | wonly_disk = new_disk; |
469 | ||
1da177e4 LT |
470 | if (new_disk <= 0) |
471 | new_disk = conf->raid_disks; | |
472 | new_disk--; | |
473 | if (new_disk == disk) { | |
8ddf9efe N |
474 | new_disk = wonly_disk; |
475 | break; | |
1da177e4 LT |
476 | } |
477 | } | |
8ddf9efe N |
478 | |
479 | if (new_disk < 0) | |
480 | goto rb_out; | |
481 | ||
1da177e4 LT |
482 | disk = new_disk; |
483 | /* now disk == new_disk == starting point for search */ | |
484 | ||
485 | /* | |
486 | * Don't change to another disk for sequential reads: | |
487 | */ | |
488 | if (conf->next_seq_sect == this_sector) | |
489 | goto rb_out; | |
490 | if (this_sector == conf->mirrors[new_disk].head_position) | |
491 | goto rb_out; | |
492 | ||
493 | current_distance = abs(this_sector - conf->mirrors[disk].head_position); | |
494 | ||
495 | /* Find the disk whose head is closest */ | |
496 | ||
497 | do { | |
498 | if (disk <= 0) | |
499 | disk = conf->raid_disks; | |
500 | disk--; | |
501 | ||
d6065f7b | 502 | rdev = rcu_dereference(conf->mirrors[disk].rdev); |
8ddf9efe | 503 | |
cf30a473 | 504 | if (!rdev || r1_bio->bios[disk] == IO_BLOCKED || |
b2d444d7 | 505 | !test_bit(In_sync, &rdev->flags) || |
8ddf9efe | 506 | test_bit(WriteMostly, &rdev->flags)) |
1da177e4 LT |
507 | continue; |
508 | ||
509 | if (!atomic_read(&rdev->nr_pending)) { | |
510 | new_disk = disk; | |
1da177e4 LT |
511 | break; |
512 | } | |
513 | new_distance = abs(this_sector - conf->mirrors[disk].head_position); | |
514 | if (new_distance < current_distance) { | |
515 | current_distance = new_distance; | |
516 | new_disk = disk; | |
1da177e4 LT |
517 | } |
518 | } while (disk != conf->last_used); | |
519 | ||
8ddf9efe | 520 | rb_out: |
1da177e4 LT |
521 | |
522 | ||
523 | if (new_disk >= 0) { | |
d6065f7b | 524 | rdev = rcu_dereference(conf->mirrors[new_disk].rdev); |
8ddf9efe N |
525 | if (!rdev) |
526 | goto retry; | |
527 | atomic_inc(&rdev->nr_pending); | |
b2d444d7 | 528 | if (!test_bit(In_sync, &rdev->flags)) { |
1da177e4 LT |
529 | /* cannot risk returning a device that failed |
530 | * before we inc'ed nr_pending | |
531 | */ | |
03c902e1 | 532 | rdev_dec_pending(rdev, conf->mddev); |
1da177e4 LT |
533 | goto retry; |
534 | } | |
8ddf9efe N |
535 | conf->next_seq_sect = this_sector + sectors; |
536 | conf->last_used = new_disk; | |
1da177e4 LT |
537 | } |
538 | rcu_read_unlock(); | |
539 | ||
540 | return new_disk; | |
541 | } | |
542 | ||
543 | static void unplug_slaves(mddev_t *mddev) | |
544 | { | |
070ec55d | 545 | conf_t *conf = mddev->private; |
1da177e4 LT |
546 | int i; |
547 | ||
548 | rcu_read_lock(); | |
549 | for (i=0; i<mddev->raid_disks; i++) { | |
d6065f7b | 550 | mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev); |
b2d444d7 | 551 | if (rdev && !test_bit(Faulty, &rdev->flags) && atomic_read(&rdev->nr_pending)) { |
165125e1 | 552 | struct request_queue *r_queue = bdev_get_queue(rdev->bdev); |
1da177e4 LT |
553 | |
554 | atomic_inc(&rdev->nr_pending); | |
555 | rcu_read_unlock(); | |
556 | ||
2ad8b1ef | 557 | blk_unplug(r_queue); |
1da177e4 LT |
558 | |
559 | rdev_dec_pending(rdev, mddev); | |
560 | rcu_read_lock(); | |
561 | } | |
562 | } | |
563 | rcu_read_unlock(); | |
564 | } | |
565 | ||
165125e1 | 566 | static void raid1_unplug(struct request_queue *q) |
1da177e4 | 567 | { |
191ea9b2 N |
568 | mddev_t *mddev = q->queuedata; |
569 | ||
570 | unplug_slaves(mddev); | |
571 | md_wakeup_thread(mddev->thread); | |
1da177e4 LT |
572 | } |
573 | ||
0d129228 N |
574 | static int raid1_congested(void *data, int bits) |
575 | { | |
576 | mddev_t *mddev = data; | |
070ec55d | 577 | conf_t *conf = mddev->private; |
0d129228 N |
578 | int i, ret = 0; |
579 | ||
3fa841d7 N |
580 | if (mddev_congested(mddev, bits)) |
581 | return 1; | |
582 | ||
0d129228 N |
583 | rcu_read_lock(); |
584 | for (i = 0; i < mddev->raid_disks; i++) { | |
585 | mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev); | |
586 | if (rdev && !test_bit(Faulty, &rdev->flags)) { | |
165125e1 | 587 | struct request_queue *q = bdev_get_queue(rdev->bdev); |
0d129228 N |
588 | |
589 | /* Note the '|| 1' - when read_balance prefers | |
590 | * non-congested targets, it can be removed | |
591 | */ | |
91a9e99d | 592 | if ((bits & (1<<BDI_async_congested)) || 1) |
0d129228 N |
593 | ret |= bdi_congested(&q->backing_dev_info, bits); |
594 | else | |
595 | ret &= bdi_congested(&q->backing_dev_info, bits); | |
596 | } | |
597 | } | |
598 | rcu_read_unlock(); | |
599 | return ret; | |
600 | } | |
601 | ||
602 | ||
a35e63ef N |
603 | static int flush_pending_writes(conf_t *conf) |
604 | { | |
605 | /* Any writes that have been queued but are awaiting | |
606 | * bitmap updates get flushed here. | |
607 | * We return 1 if any requests were actually submitted. | |
608 | */ | |
609 | int rv = 0; | |
610 | ||
611 | spin_lock_irq(&conf->device_lock); | |
612 | ||
613 | if (conf->pending_bio_list.head) { | |
614 | struct bio *bio; | |
615 | bio = bio_list_get(&conf->pending_bio_list); | |
616 | blk_remove_plug(conf->mddev->queue); | |
617 | spin_unlock_irq(&conf->device_lock); | |
618 | /* flush any pending bitmap writes to | |
619 | * disk before proceeding w/ I/O */ | |
620 | bitmap_unplug(conf->mddev->bitmap); | |
621 | ||
622 | while (bio) { /* submit pending writes */ | |
623 | struct bio *next = bio->bi_next; | |
624 | bio->bi_next = NULL; | |
625 | generic_make_request(bio); | |
626 | bio = next; | |
627 | } | |
628 | rv = 1; | |
629 | } else | |
630 | spin_unlock_irq(&conf->device_lock); | |
631 | return rv; | |
632 | } | |
633 | ||
17999be4 N |
634 | /* Barriers.... |
635 | * Sometimes we need to suspend IO while we do something else, | |
636 | * either some resync/recovery, or reconfigure the array. | |
637 | * To do this we raise a 'barrier'. | |
638 | * The 'barrier' is a counter that can be raised multiple times | |
639 | * to count how many activities are happening which preclude | |
640 | * normal IO. | |
641 | * We can only raise the barrier if there is no pending IO. | |
642 | * i.e. if nr_pending == 0. | |
643 | * We choose only to raise the barrier if no-one is waiting for the | |
644 | * barrier to go down. This means that as soon as an IO request | |
645 | * is ready, no other operations which require a barrier will start | |
646 | * until the IO request has had a chance. | |
647 | * | |
648 | * So: regular IO calls 'wait_barrier'. When that returns there | |
649 | * is no backgroup IO happening, It must arrange to call | |
650 | * allow_barrier when it has finished its IO. | |
651 | * backgroup IO calls must call raise_barrier. Once that returns | |
652 | * there is no normal IO happeing. It must arrange to call | |
653 | * lower_barrier when the particular background IO completes. | |
1da177e4 LT |
654 | */ |
655 | #define RESYNC_DEPTH 32 | |
656 | ||
17999be4 | 657 | static void raise_barrier(conf_t *conf) |
1da177e4 LT |
658 | { |
659 | spin_lock_irq(&conf->resync_lock); | |
17999be4 N |
660 | |
661 | /* Wait until no block IO is waiting */ | |
662 | wait_event_lock_irq(conf->wait_barrier, !conf->nr_waiting, | |
663 | conf->resync_lock, | |
664 | raid1_unplug(conf->mddev->queue)); | |
665 | ||
666 | /* block any new IO from starting */ | |
667 | conf->barrier++; | |
668 | ||
669 | /* No wait for all pending IO to complete */ | |
670 | wait_event_lock_irq(conf->wait_barrier, | |
671 | !conf->nr_pending && conf->barrier < RESYNC_DEPTH, | |
672 | conf->resync_lock, | |
673 | raid1_unplug(conf->mddev->queue)); | |
674 | ||
675 | spin_unlock_irq(&conf->resync_lock); | |
676 | } | |
677 | ||
678 | static void lower_barrier(conf_t *conf) | |
679 | { | |
680 | unsigned long flags; | |
709ae487 | 681 | BUG_ON(conf->barrier <= 0); |
17999be4 N |
682 | spin_lock_irqsave(&conf->resync_lock, flags); |
683 | conf->barrier--; | |
684 | spin_unlock_irqrestore(&conf->resync_lock, flags); | |
685 | wake_up(&conf->wait_barrier); | |
686 | } | |
687 | ||
688 | static void wait_barrier(conf_t *conf) | |
689 | { | |
690 | spin_lock_irq(&conf->resync_lock); | |
691 | if (conf->barrier) { | |
692 | conf->nr_waiting++; | |
693 | wait_event_lock_irq(conf->wait_barrier, !conf->barrier, | |
694 | conf->resync_lock, | |
695 | raid1_unplug(conf->mddev->queue)); | |
696 | conf->nr_waiting--; | |
1da177e4 | 697 | } |
17999be4 | 698 | conf->nr_pending++; |
1da177e4 LT |
699 | spin_unlock_irq(&conf->resync_lock); |
700 | } | |
701 | ||
17999be4 N |
702 | static void allow_barrier(conf_t *conf) |
703 | { | |
704 | unsigned long flags; | |
705 | spin_lock_irqsave(&conf->resync_lock, flags); | |
706 | conf->nr_pending--; | |
707 | spin_unlock_irqrestore(&conf->resync_lock, flags); | |
708 | wake_up(&conf->wait_barrier); | |
709 | } | |
710 | ||
ddaf22ab N |
711 | static void freeze_array(conf_t *conf) |
712 | { | |
713 | /* stop syncio and normal IO and wait for everything to | |
714 | * go quite. | |
715 | * We increment barrier and nr_waiting, and then | |
1c830532 N |
716 | * wait until nr_pending match nr_queued+1 |
717 | * This is called in the context of one normal IO request | |
718 | * that has failed. Thus any sync request that might be pending | |
719 | * will be blocked by nr_pending, and we need to wait for | |
720 | * pending IO requests to complete or be queued for re-try. | |
721 | * Thus the number queued (nr_queued) plus this request (1) | |
722 | * must match the number of pending IOs (nr_pending) before | |
723 | * we continue. | |
ddaf22ab N |
724 | */ |
725 | spin_lock_irq(&conf->resync_lock); | |
726 | conf->barrier++; | |
727 | conf->nr_waiting++; | |
728 | wait_event_lock_irq(conf->wait_barrier, | |
1c830532 | 729 | conf->nr_pending == conf->nr_queued+1, |
ddaf22ab | 730 | conf->resync_lock, |
a35e63ef N |
731 | ({ flush_pending_writes(conf); |
732 | raid1_unplug(conf->mddev->queue); })); | |
ddaf22ab N |
733 | spin_unlock_irq(&conf->resync_lock); |
734 | } | |
735 | static void unfreeze_array(conf_t *conf) | |
736 | { | |
737 | /* reverse the effect of the freeze */ | |
738 | spin_lock_irq(&conf->resync_lock); | |
739 | conf->barrier--; | |
740 | conf->nr_waiting--; | |
741 | wake_up(&conf->wait_barrier); | |
742 | spin_unlock_irq(&conf->resync_lock); | |
743 | } | |
744 | ||
17999be4 | 745 | |
4e78064f N |
746 | /* duplicate the data pages for behind I/O |
747 | * We return a list of bio_vec rather than just page pointers | |
748 | * as it makes freeing easier | |
749 | */ | |
750 | static struct bio_vec *alloc_behind_pages(struct bio *bio) | |
4b6d287f N |
751 | { |
752 | int i; | |
753 | struct bio_vec *bvec; | |
4e78064f | 754 | struct bio_vec *pages = kzalloc(bio->bi_vcnt * sizeof(struct bio_vec), |
4b6d287f N |
755 | GFP_NOIO); |
756 | if (unlikely(!pages)) | |
757 | goto do_sync_io; | |
758 | ||
4b6d287f | 759 | bio_for_each_segment(bvec, bio, i) { |
4e78064f N |
760 | pages[i].bv_page = alloc_page(GFP_NOIO); |
761 | if (unlikely(!pages[i].bv_page)) | |
4b6d287f | 762 | goto do_sync_io; |
4e78064f | 763 | memcpy(kmap(pages[i].bv_page) + bvec->bv_offset, |
4b6d287f | 764 | kmap(bvec->bv_page) + bvec->bv_offset, bvec->bv_len); |
4e78064f | 765 | kunmap(pages[i].bv_page); |
4b6d287f N |
766 | kunmap(bvec->bv_page); |
767 | } | |
768 | ||
769 | return pages; | |
770 | ||
771 | do_sync_io: | |
772 | if (pages) | |
4e78064f N |
773 | for (i = 0; i < bio->bi_vcnt && pages[i].bv_page; i++) |
774 | put_page(pages[i].bv_page); | |
4b6d287f N |
775 | kfree(pages); |
776 | PRINTK("%dB behind alloc failed, doing sync I/O\n", bio->bi_size); | |
777 | return NULL; | |
778 | } | |
779 | ||
21a52c6d | 780 | static int make_request(mddev_t *mddev, struct bio * bio) |
1da177e4 | 781 | { |
070ec55d | 782 | conf_t *conf = mddev->private; |
1da177e4 LT |
783 | mirror_info_t *mirror; |
784 | r1bio_t *r1_bio; | |
785 | struct bio *read_bio; | |
191ea9b2 | 786 | int i, targets = 0, disks; |
84255d10 | 787 | struct bitmap *bitmap; |
191ea9b2 | 788 | unsigned long flags; |
4e78064f | 789 | struct bio_vec *behind_pages = NULL; |
a362357b | 790 | const int rw = bio_data_dir(bio); |
2c7d46ec | 791 | const unsigned long do_sync = (bio->bi_rw & REQ_SYNC); |
e9c7469b | 792 | const unsigned long do_flush_fua = (bio->bi_rw & (REQ_FLUSH | REQ_FUA)); |
6bfe0b49 | 793 | mdk_rdev_t *blocked_rdev; |
191ea9b2 | 794 | |
1da177e4 LT |
795 | /* |
796 | * Register the new request and wait if the reconstruction | |
797 | * thread has put up a bar for new requests. | |
798 | * Continue immediately if no resync is active currently. | |
799 | */ | |
62de608d | 800 | |
3d310eb7 N |
801 | md_write_start(mddev, bio); /* wait on superblock update early */ |
802 | ||
6eef4b21 N |
803 | if (bio_data_dir(bio) == WRITE && |
804 | bio->bi_sector + bio->bi_size/512 > mddev->suspend_lo && | |
805 | bio->bi_sector < mddev->suspend_hi) { | |
806 | /* As the suspend_* range is controlled by | |
807 | * userspace, we want an interruptible | |
808 | * wait. | |
809 | */ | |
810 | DEFINE_WAIT(w); | |
811 | for (;;) { | |
812 | flush_signals(current); | |
813 | prepare_to_wait(&conf->wait_barrier, | |
814 | &w, TASK_INTERRUPTIBLE); | |
815 | if (bio->bi_sector + bio->bi_size/512 <= mddev->suspend_lo || | |
816 | bio->bi_sector >= mddev->suspend_hi) | |
817 | break; | |
818 | schedule(); | |
819 | } | |
820 | finish_wait(&conf->wait_barrier, &w); | |
821 | } | |
62de608d | 822 | |
17999be4 | 823 | wait_barrier(conf); |
1da177e4 | 824 | |
84255d10 N |
825 | bitmap = mddev->bitmap; |
826 | ||
1da177e4 LT |
827 | /* |
828 | * make_request() can abort the operation when READA is being | |
829 | * used and no empty request is available. | |
830 | * | |
831 | */ | |
832 | r1_bio = mempool_alloc(conf->r1bio_pool, GFP_NOIO); | |
833 | ||
834 | r1_bio->master_bio = bio; | |
835 | r1_bio->sectors = bio->bi_size >> 9; | |
191ea9b2 | 836 | r1_bio->state = 0; |
1da177e4 LT |
837 | r1_bio->mddev = mddev; |
838 | r1_bio->sector = bio->bi_sector; | |
839 | ||
a362357b | 840 | if (rw == READ) { |
1da177e4 LT |
841 | /* |
842 | * read balancing logic: | |
843 | */ | |
844 | int rdisk = read_balance(conf, r1_bio); | |
845 | ||
846 | if (rdisk < 0) { | |
847 | /* couldn't find anywhere to read from */ | |
848 | raid_end_bio_io(r1_bio); | |
849 | return 0; | |
850 | } | |
851 | mirror = conf->mirrors + rdisk; | |
852 | ||
e555190d N |
853 | if (test_bit(WriteMostly, &mirror->rdev->flags) && |
854 | bitmap) { | |
855 | /* Reading from a write-mostly device must | |
856 | * take care not to over-take any writes | |
857 | * that are 'behind' | |
858 | */ | |
859 | wait_event(bitmap->behind_wait, | |
860 | atomic_read(&bitmap->behind_writes) == 0); | |
861 | } | |
1da177e4 LT |
862 | r1_bio->read_disk = rdisk; |
863 | ||
864 | read_bio = bio_clone(bio, GFP_NOIO); | |
865 | ||
866 | r1_bio->bios[rdisk] = read_bio; | |
867 | ||
868 | read_bio->bi_sector = r1_bio->sector + mirror->rdev->data_offset; | |
869 | read_bio->bi_bdev = mirror->rdev->bdev; | |
870 | read_bio->bi_end_io = raid1_end_read_request; | |
7b6d91da | 871 | read_bio->bi_rw = READ | do_sync; |
1da177e4 LT |
872 | read_bio->bi_private = r1_bio; |
873 | ||
874 | generic_make_request(read_bio); | |
875 | return 0; | |
876 | } | |
877 | ||
878 | /* | |
879 | * WRITE: | |
880 | */ | |
881 | /* first select target devices under spinlock and | |
882 | * inc refcount on their rdev. Record them by setting | |
883 | * bios[x] to bio | |
884 | */ | |
885 | disks = conf->raid_disks; | |
6bfe0b49 DW |
886 | retry_write: |
887 | blocked_rdev = NULL; | |
1da177e4 LT |
888 | rcu_read_lock(); |
889 | for (i = 0; i < disks; i++) { | |
6bfe0b49 DW |
890 | mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev); |
891 | if (rdev && unlikely(test_bit(Blocked, &rdev->flags))) { | |
892 | atomic_inc(&rdev->nr_pending); | |
893 | blocked_rdev = rdev; | |
894 | break; | |
895 | } | |
896 | if (rdev && !test_bit(Faulty, &rdev->flags)) { | |
1da177e4 | 897 | atomic_inc(&rdev->nr_pending); |
b2d444d7 | 898 | if (test_bit(Faulty, &rdev->flags)) { |
03c902e1 | 899 | rdev_dec_pending(rdev, mddev); |
1da177e4 | 900 | r1_bio->bios[i] = NULL; |
964147d5 | 901 | } else { |
1da177e4 | 902 | r1_bio->bios[i] = bio; |
964147d5 N |
903 | targets++; |
904 | } | |
1da177e4 LT |
905 | } else |
906 | r1_bio->bios[i] = NULL; | |
907 | } | |
908 | rcu_read_unlock(); | |
909 | ||
6bfe0b49 DW |
910 | if (unlikely(blocked_rdev)) { |
911 | /* Wait for this device to become unblocked */ | |
912 | int j; | |
913 | ||
914 | for (j = 0; j < i; j++) | |
915 | if (r1_bio->bios[j]) | |
916 | rdev_dec_pending(conf->mirrors[j].rdev, mddev); | |
917 | ||
918 | allow_barrier(conf); | |
919 | md_wait_for_blocked_rdev(blocked_rdev, mddev); | |
920 | wait_barrier(conf); | |
921 | goto retry_write; | |
922 | } | |
923 | ||
4b6d287f N |
924 | BUG_ON(targets == 0); /* we never fail the last device */ |
925 | ||
191ea9b2 N |
926 | if (targets < conf->raid_disks) { |
927 | /* array is degraded, we will not clear the bitmap | |
928 | * on I/O completion (see raid1_end_write_request) */ | |
929 | set_bit(R1BIO_Degraded, &r1_bio->state); | |
930 | } | |
931 | ||
e555190d N |
932 | /* do behind I/O ? |
933 | * Not if there are too many, or cannot allocate memory, | |
934 | * or a reader on WriteMostly is waiting for behind writes | |
935 | * to flush */ | |
4b6d287f | 936 | if (bitmap && |
42a04b50 N |
937 | (atomic_read(&bitmap->behind_writes) |
938 | < mddev->bitmap_info.max_write_behind) && | |
e555190d | 939 | !waitqueue_active(&bitmap->behind_wait) && |
4b6d287f N |
940 | (behind_pages = alloc_behind_pages(bio)) != NULL) |
941 | set_bit(R1BIO_BehindIO, &r1_bio->state); | |
942 | ||
4e78064f | 943 | atomic_set(&r1_bio->remaining, 1); |
4b6d287f | 944 | atomic_set(&r1_bio->behind_remaining, 0); |
06d91a5f | 945 | |
4e78064f N |
946 | bitmap_startwrite(bitmap, bio->bi_sector, r1_bio->sectors, |
947 | test_bit(R1BIO_BehindIO, &r1_bio->state)); | |
1da177e4 LT |
948 | for (i = 0; i < disks; i++) { |
949 | struct bio *mbio; | |
950 | if (!r1_bio->bios[i]) | |
951 | continue; | |
952 | ||
953 | mbio = bio_clone(bio, GFP_NOIO); | |
954 | r1_bio->bios[i] = mbio; | |
955 | ||
956 | mbio->bi_sector = r1_bio->sector + conf->mirrors[i].rdev->data_offset; | |
957 | mbio->bi_bdev = conf->mirrors[i].rdev->bdev; | |
958 | mbio->bi_end_io = raid1_end_write_request; | |
e9c7469b | 959 | mbio->bi_rw = WRITE | do_flush_fua | do_sync; |
1da177e4 LT |
960 | mbio->bi_private = r1_bio; |
961 | ||
4b6d287f N |
962 | if (behind_pages) { |
963 | struct bio_vec *bvec; | |
964 | int j; | |
965 | ||
966 | /* Yes, I really want the '__' version so that | |
967 | * we clear any unused pointer in the io_vec, rather | |
968 | * than leave them unchanged. This is important | |
969 | * because when we come to free the pages, we won't | |
970 | * know the originial bi_idx, so we just free | |
971 | * them all | |
972 | */ | |
973 | __bio_for_each_segment(bvec, mbio, j, 0) | |
4e78064f | 974 | bvec->bv_page = behind_pages[j].bv_page; |
4b6d287f N |
975 | if (test_bit(WriteMostly, &conf->mirrors[i].rdev->flags)) |
976 | atomic_inc(&r1_bio->behind_remaining); | |
977 | } | |
978 | ||
1da177e4 | 979 | atomic_inc(&r1_bio->remaining); |
4e78064f N |
980 | spin_lock_irqsave(&conf->device_lock, flags); |
981 | bio_list_add(&conf->pending_bio_list, mbio); | |
982 | blk_plug_device(mddev->queue); | |
983 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
1da177e4 | 984 | } |
4e78064f | 985 | r1_bio_write_done(r1_bio, bio->bi_vcnt, behind_pages, behind_pages != NULL); |
4b6d287f | 986 | kfree(behind_pages); /* the behind pages are attached to the bios now */ |
1da177e4 | 987 | |
4e78064f | 988 | /* In case raid1d snuck in to freeze_array */ |
a35e63ef N |
989 | wake_up(&conf->wait_barrier); |
990 | ||
e3881a68 LE |
991 | if (do_sync) |
992 | md_wakeup_thread(mddev->thread); | |
191ea9b2 | 993 | |
1da177e4 LT |
994 | return 0; |
995 | } | |
996 | ||
997 | static void status(struct seq_file *seq, mddev_t *mddev) | |
998 | { | |
070ec55d | 999 | conf_t *conf = mddev->private; |
1da177e4 LT |
1000 | int i; |
1001 | ||
1002 | seq_printf(seq, " [%d/%d] [", conf->raid_disks, | |
11ce99e6 | 1003 | conf->raid_disks - mddev->degraded); |
ddac7c7e N |
1004 | rcu_read_lock(); |
1005 | for (i = 0; i < conf->raid_disks; i++) { | |
1006 | mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev); | |
1da177e4 | 1007 | seq_printf(seq, "%s", |
ddac7c7e N |
1008 | rdev && test_bit(In_sync, &rdev->flags) ? "U" : "_"); |
1009 | } | |
1010 | rcu_read_unlock(); | |
1da177e4 LT |
1011 | seq_printf(seq, "]"); |
1012 | } | |
1013 | ||
1014 | ||
1015 | static void error(mddev_t *mddev, mdk_rdev_t *rdev) | |
1016 | { | |
1017 | char b[BDEVNAME_SIZE]; | |
070ec55d | 1018 | conf_t *conf = mddev->private; |
1da177e4 LT |
1019 | |
1020 | /* | |
1021 | * If it is not operational, then we have already marked it as dead | |
1022 | * else if it is the last working disks, ignore the error, let the | |
1023 | * next level up know. | |
1024 | * else mark the drive as failed | |
1025 | */ | |
b2d444d7 | 1026 | if (test_bit(In_sync, &rdev->flags) |
4044ba58 | 1027 | && (conf->raid_disks - mddev->degraded) == 1) { |
1da177e4 LT |
1028 | /* |
1029 | * Don't fail the drive, act as though we were just a | |
4044ba58 N |
1030 | * normal single drive. |
1031 | * However don't try a recovery from this drive as | |
1032 | * it is very likely to fail. | |
1da177e4 | 1033 | */ |
4044ba58 | 1034 | mddev->recovery_disabled = 1; |
1da177e4 | 1035 | return; |
4044ba58 | 1036 | } |
c04be0aa N |
1037 | if (test_and_clear_bit(In_sync, &rdev->flags)) { |
1038 | unsigned long flags; | |
1039 | spin_lock_irqsave(&conf->device_lock, flags); | |
1da177e4 | 1040 | mddev->degraded++; |
dd00a99e | 1041 | set_bit(Faulty, &rdev->flags); |
c04be0aa | 1042 | spin_unlock_irqrestore(&conf->device_lock, flags); |
1da177e4 LT |
1043 | /* |
1044 | * if recovery is running, make sure it aborts. | |
1045 | */ | |
dfc70645 | 1046 | set_bit(MD_RECOVERY_INTR, &mddev->recovery); |
dd00a99e N |
1047 | } else |
1048 | set_bit(Faulty, &rdev->flags); | |
850b2b42 | 1049 | set_bit(MD_CHANGE_DEVS, &mddev->flags); |
9dd1e2fa N |
1050 | printk(KERN_ALERT "md/raid1:%s: Disk failure on %s, disabling device.\n" |
1051 | KERN_ALERT "md/raid1:%s: Operation continuing on %d devices.\n", | |
1052 | mdname(mddev), bdevname(rdev->bdev, b), | |
1053 | mdname(mddev), conf->raid_disks - mddev->degraded); | |
1da177e4 LT |
1054 | } |
1055 | ||
1056 | static void print_conf(conf_t *conf) | |
1057 | { | |
1058 | int i; | |
1da177e4 | 1059 | |
9dd1e2fa | 1060 | printk(KERN_DEBUG "RAID1 conf printout:\n"); |
1da177e4 | 1061 | if (!conf) { |
9dd1e2fa | 1062 | printk(KERN_DEBUG "(!conf)\n"); |
1da177e4 LT |
1063 | return; |
1064 | } | |
9dd1e2fa | 1065 | printk(KERN_DEBUG " --- wd:%d rd:%d\n", conf->raid_disks - conf->mddev->degraded, |
1da177e4 LT |
1066 | conf->raid_disks); |
1067 | ||
ddac7c7e | 1068 | rcu_read_lock(); |
1da177e4 LT |
1069 | for (i = 0; i < conf->raid_disks; i++) { |
1070 | char b[BDEVNAME_SIZE]; | |
ddac7c7e N |
1071 | mdk_rdev_t *rdev = rcu_dereference(conf->mirrors[i].rdev); |
1072 | if (rdev) | |
9dd1e2fa | 1073 | printk(KERN_DEBUG " disk %d, wo:%d, o:%d, dev:%s\n", |
ddac7c7e N |
1074 | i, !test_bit(In_sync, &rdev->flags), |
1075 | !test_bit(Faulty, &rdev->flags), | |
1076 | bdevname(rdev->bdev,b)); | |
1da177e4 | 1077 | } |
ddac7c7e | 1078 | rcu_read_unlock(); |
1da177e4 LT |
1079 | } |
1080 | ||
1081 | static void close_sync(conf_t *conf) | |
1082 | { | |
17999be4 N |
1083 | wait_barrier(conf); |
1084 | allow_barrier(conf); | |
1da177e4 LT |
1085 | |
1086 | mempool_destroy(conf->r1buf_pool); | |
1087 | conf->r1buf_pool = NULL; | |
1088 | } | |
1089 | ||
1090 | static int raid1_spare_active(mddev_t *mddev) | |
1091 | { | |
1092 | int i; | |
1093 | conf_t *conf = mddev->private; | |
6b965620 N |
1094 | int count = 0; |
1095 | unsigned long flags; | |
1da177e4 LT |
1096 | |
1097 | /* | |
1098 | * Find all failed disks within the RAID1 configuration | |
ddac7c7e N |
1099 | * and mark them readable. |
1100 | * Called under mddev lock, so rcu protection not needed. | |
1da177e4 LT |
1101 | */ |
1102 | for (i = 0; i < conf->raid_disks; i++) { | |
ddac7c7e N |
1103 | mdk_rdev_t *rdev = conf->mirrors[i].rdev; |
1104 | if (rdev | |
1105 | && !test_bit(Faulty, &rdev->flags) | |
c04be0aa | 1106 | && !test_and_set_bit(In_sync, &rdev->flags)) { |
6b965620 | 1107 | count++; |
e6ffbcb6 | 1108 | sysfs_notify_dirent(rdev->sysfs_state); |
1da177e4 LT |
1109 | } |
1110 | } | |
6b965620 N |
1111 | spin_lock_irqsave(&conf->device_lock, flags); |
1112 | mddev->degraded -= count; | |
1113 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
1da177e4 LT |
1114 | |
1115 | print_conf(conf); | |
6b965620 | 1116 | return count; |
1da177e4 LT |
1117 | } |
1118 | ||
1119 | ||
1120 | static int raid1_add_disk(mddev_t *mddev, mdk_rdev_t *rdev) | |
1121 | { | |
1122 | conf_t *conf = mddev->private; | |
199050ea | 1123 | int err = -EEXIST; |
41158c7e | 1124 | int mirror = 0; |
1da177e4 | 1125 | mirror_info_t *p; |
6c2fce2e NB |
1126 | int first = 0; |
1127 | int last = mddev->raid_disks - 1; | |
1da177e4 | 1128 | |
6c2fce2e NB |
1129 | if (rdev->raid_disk >= 0) |
1130 | first = last = rdev->raid_disk; | |
1131 | ||
1132 | for (mirror = first; mirror <= last; mirror++) | |
1da177e4 LT |
1133 | if ( !(p=conf->mirrors+mirror)->rdev) { |
1134 | ||
8f6c2e4b MP |
1135 | disk_stack_limits(mddev->gendisk, rdev->bdev, |
1136 | rdev->data_offset << 9); | |
627a2d3c N |
1137 | /* as we don't honour merge_bvec_fn, we must |
1138 | * never risk violating it, so limit | |
1139 | * ->max_segments to one lying with a single | |
1140 | * page, as a one page request is never in | |
1141 | * violation. | |
1da177e4 | 1142 | */ |
627a2d3c N |
1143 | if (rdev->bdev->bd_disk->queue->merge_bvec_fn) { |
1144 | blk_queue_max_segments(mddev->queue, 1); | |
1145 | blk_queue_segment_boundary(mddev->queue, | |
1146 | PAGE_CACHE_SIZE - 1); | |
1147 | } | |
1da177e4 LT |
1148 | |
1149 | p->head_position = 0; | |
1150 | rdev->raid_disk = mirror; | |
199050ea | 1151 | err = 0; |
6aea114a N |
1152 | /* As all devices are equivalent, we don't need a full recovery |
1153 | * if this was recently any drive of the array | |
1154 | */ | |
1155 | if (rdev->saved_raid_disk < 0) | |
41158c7e | 1156 | conf->fullsync = 1; |
d6065f7b | 1157 | rcu_assign_pointer(p->rdev, rdev); |
1da177e4 LT |
1158 | break; |
1159 | } | |
ac5e7113 | 1160 | md_integrity_add_rdev(rdev, mddev); |
1da177e4 | 1161 | print_conf(conf); |
199050ea | 1162 | return err; |
1da177e4 LT |
1163 | } |
1164 | ||
1165 | static int raid1_remove_disk(mddev_t *mddev, int number) | |
1166 | { | |
1167 | conf_t *conf = mddev->private; | |
1168 | int err = 0; | |
1169 | mdk_rdev_t *rdev; | |
1170 | mirror_info_t *p = conf->mirrors+ number; | |
1171 | ||
1172 | print_conf(conf); | |
1173 | rdev = p->rdev; | |
1174 | if (rdev) { | |
b2d444d7 | 1175 | if (test_bit(In_sync, &rdev->flags) || |
1da177e4 LT |
1176 | atomic_read(&rdev->nr_pending)) { |
1177 | err = -EBUSY; | |
1178 | goto abort; | |
1179 | } | |
dfc70645 N |
1180 | /* Only remove non-faulty devices is recovery |
1181 | * is not possible. | |
1182 | */ | |
1183 | if (!test_bit(Faulty, &rdev->flags) && | |
1184 | mddev->degraded < conf->raid_disks) { | |
1185 | err = -EBUSY; | |
1186 | goto abort; | |
1187 | } | |
1da177e4 | 1188 | p->rdev = NULL; |
fbd568a3 | 1189 | synchronize_rcu(); |
1da177e4 LT |
1190 | if (atomic_read(&rdev->nr_pending)) { |
1191 | /* lost the race, try later */ | |
1192 | err = -EBUSY; | |
1193 | p->rdev = rdev; | |
ac5e7113 | 1194 | goto abort; |
1da177e4 | 1195 | } |
ac5e7113 | 1196 | md_integrity_register(mddev); |
1da177e4 LT |
1197 | } |
1198 | abort: | |
1199 | ||
1200 | print_conf(conf); | |
1201 | return err; | |
1202 | } | |
1203 | ||
1204 | ||
6712ecf8 | 1205 | static void end_sync_read(struct bio *bio, int error) |
1da177e4 | 1206 | { |
7b92813c | 1207 | r1bio_t *r1_bio = bio->bi_private; |
d11c171e | 1208 | int i; |
1da177e4 | 1209 | |
d11c171e N |
1210 | for (i=r1_bio->mddev->raid_disks; i--; ) |
1211 | if (r1_bio->bios[i] == bio) | |
1212 | break; | |
1213 | BUG_ON(i < 0); | |
1214 | update_head_pos(i, r1_bio); | |
1da177e4 LT |
1215 | /* |
1216 | * we have read a block, now it needs to be re-written, | |
1217 | * or re-read if the read failed. | |
1218 | * We don't do much here, just schedule handling by raid1d | |
1219 | */ | |
69382e85 | 1220 | if (test_bit(BIO_UPTODATE, &bio->bi_flags)) |
1da177e4 | 1221 | set_bit(R1BIO_Uptodate, &r1_bio->state); |
d11c171e N |
1222 | |
1223 | if (atomic_dec_and_test(&r1_bio->remaining)) | |
1224 | reschedule_retry(r1_bio); | |
1da177e4 LT |
1225 | } |
1226 | ||
6712ecf8 | 1227 | static void end_sync_write(struct bio *bio, int error) |
1da177e4 LT |
1228 | { |
1229 | int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags); | |
7b92813c | 1230 | r1bio_t *r1_bio = bio->bi_private; |
1da177e4 | 1231 | mddev_t *mddev = r1_bio->mddev; |
070ec55d | 1232 | conf_t *conf = mddev->private; |
1da177e4 LT |
1233 | int i; |
1234 | int mirror=0; | |
1235 | ||
1da177e4 LT |
1236 | for (i = 0; i < conf->raid_disks; i++) |
1237 | if (r1_bio->bios[i] == bio) { | |
1238 | mirror = i; | |
1239 | break; | |
1240 | } | |
6b1117d5 | 1241 | if (!uptodate) { |
57dab0bd | 1242 | sector_t sync_blocks = 0; |
6b1117d5 N |
1243 | sector_t s = r1_bio->sector; |
1244 | long sectors_to_go = r1_bio->sectors; | |
1245 | /* make sure these bits doesn't get cleared. */ | |
1246 | do { | |
5e3db645 | 1247 | bitmap_end_sync(mddev->bitmap, s, |
6b1117d5 N |
1248 | &sync_blocks, 1); |
1249 | s += sync_blocks; | |
1250 | sectors_to_go -= sync_blocks; | |
1251 | } while (sectors_to_go > 0); | |
1da177e4 | 1252 | md_error(mddev, conf->mirrors[mirror].rdev); |
6b1117d5 | 1253 | } |
e3b9703e | 1254 | |
1da177e4 LT |
1255 | update_head_pos(mirror, r1_bio); |
1256 | ||
1257 | if (atomic_dec_and_test(&r1_bio->remaining)) { | |
73d5c38a | 1258 | sector_t s = r1_bio->sectors; |
1da177e4 | 1259 | put_buf(r1_bio); |
73d5c38a | 1260 | md_done_sync(mddev, s, uptodate); |
1da177e4 | 1261 | } |
1da177e4 LT |
1262 | } |
1263 | ||
1264 | static void sync_request_write(mddev_t *mddev, r1bio_t *r1_bio) | |
1265 | { | |
070ec55d | 1266 | conf_t *conf = mddev->private; |
1da177e4 LT |
1267 | int i; |
1268 | int disks = conf->raid_disks; | |
1269 | struct bio *bio, *wbio; | |
1270 | ||
1271 | bio = r1_bio->bios[r1_bio->read_disk]; | |
1272 | ||
69382e85 | 1273 | |
d11c171e N |
1274 | if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) { |
1275 | /* We have read all readable devices. If we haven't | |
1276 | * got the block, then there is no hope left. | |
1277 | * If we have, then we want to do a comparison | |
1278 | * and skip the write if everything is the same. | |
1279 | * If any blocks failed to read, then we need to | |
1280 | * attempt an over-write | |
1281 | */ | |
1282 | int primary; | |
1283 | if (!test_bit(R1BIO_Uptodate, &r1_bio->state)) { | |
1284 | for (i=0; i<mddev->raid_disks; i++) | |
1285 | if (r1_bio->bios[i]->bi_end_io == end_sync_read) | |
1286 | md_error(mddev, conf->mirrors[i].rdev); | |
1287 | ||
1288 | md_done_sync(mddev, r1_bio->sectors, 1); | |
1289 | put_buf(r1_bio); | |
1290 | return; | |
1291 | } | |
1292 | for (primary=0; primary<mddev->raid_disks; primary++) | |
1293 | if (r1_bio->bios[primary]->bi_end_io == end_sync_read && | |
1294 | test_bit(BIO_UPTODATE, &r1_bio->bios[primary]->bi_flags)) { | |
1295 | r1_bio->bios[primary]->bi_end_io = NULL; | |
03c902e1 | 1296 | rdev_dec_pending(conf->mirrors[primary].rdev, mddev); |
d11c171e N |
1297 | break; |
1298 | } | |
1299 | r1_bio->read_disk = primary; | |
1300 | for (i=0; i<mddev->raid_disks; i++) | |
ed456662 | 1301 | if (r1_bio->bios[i]->bi_end_io == end_sync_read) { |
d11c171e N |
1302 | int j; |
1303 | int vcnt = r1_bio->sectors >> (PAGE_SHIFT- 9); | |
1304 | struct bio *pbio = r1_bio->bios[primary]; | |
1305 | struct bio *sbio = r1_bio->bios[i]; | |
ed456662 MA |
1306 | |
1307 | if (test_bit(BIO_UPTODATE, &sbio->bi_flags)) { | |
1308 | for (j = vcnt; j-- ; ) { | |
1309 | struct page *p, *s; | |
1310 | p = pbio->bi_io_vec[j].bv_page; | |
1311 | s = sbio->bi_io_vec[j].bv_page; | |
1312 | if (memcmp(page_address(p), | |
1313 | page_address(s), | |
1314 | PAGE_SIZE)) | |
1315 | break; | |
1316 | } | |
1317 | } else | |
1318 | j = 0; | |
d11c171e N |
1319 | if (j >= 0) |
1320 | mddev->resync_mismatches += r1_bio->sectors; | |
cf7a4416 N |
1321 | if (j < 0 || (test_bit(MD_RECOVERY_CHECK, &mddev->recovery) |
1322 | && test_bit(BIO_UPTODATE, &sbio->bi_flags))) { | |
d11c171e | 1323 | sbio->bi_end_io = NULL; |
03c902e1 N |
1324 | rdev_dec_pending(conf->mirrors[i].rdev, mddev); |
1325 | } else { | |
d11c171e | 1326 | /* fixup the bio for reuse */ |
698b18c1 | 1327 | int size; |
d11c171e N |
1328 | sbio->bi_vcnt = vcnt; |
1329 | sbio->bi_size = r1_bio->sectors << 9; | |
1330 | sbio->bi_idx = 0; | |
1331 | sbio->bi_phys_segments = 0; | |
d11c171e N |
1332 | sbio->bi_flags &= ~(BIO_POOL_MASK - 1); |
1333 | sbio->bi_flags |= 1 << BIO_UPTODATE; | |
1334 | sbio->bi_next = NULL; | |
1335 | sbio->bi_sector = r1_bio->sector + | |
1336 | conf->mirrors[i].rdev->data_offset; | |
1337 | sbio->bi_bdev = conf->mirrors[i].rdev->bdev; | |
698b18c1 N |
1338 | size = sbio->bi_size; |
1339 | for (j = 0; j < vcnt ; j++) { | |
1340 | struct bio_vec *bi; | |
1341 | bi = &sbio->bi_io_vec[j]; | |
1342 | bi->bv_offset = 0; | |
1343 | if (size > PAGE_SIZE) | |
1344 | bi->bv_len = PAGE_SIZE; | |
1345 | else | |
1346 | bi->bv_len = size; | |
1347 | size -= PAGE_SIZE; | |
1348 | memcpy(page_address(bi->bv_page), | |
3eda22d1 N |
1349 | page_address(pbio->bi_io_vec[j].bv_page), |
1350 | PAGE_SIZE); | |
698b18c1 | 1351 | } |
3eda22d1 | 1352 | |
d11c171e N |
1353 | } |
1354 | } | |
1355 | } | |
1da177e4 | 1356 | if (!test_bit(R1BIO_Uptodate, &r1_bio->state)) { |
69382e85 N |
1357 | /* ouch - failed to read all of that. |
1358 | * Try some synchronous reads of other devices to get | |
1359 | * good data, much like with normal read errors. Only | |
ddac7c7e | 1360 | * read into the pages we already have so we don't |
69382e85 N |
1361 | * need to re-issue the read request. |
1362 | * We don't need to freeze the array, because being in an | |
1363 | * active sync request, there is no normal IO, and | |
1364 | * no overlapping syncs. | |
1da177e4 | 1365 | */ |
69382e85 N |
1366 | sector_t sect = r1_bio->sector; |
1367 | int sectors = r1_bio->sectors; | |
1368 | int idx = 0; | |
1369 | ||
1370 | while(sectors) { | |
1371 | int s = sectors; | |
1372 | int d = r1_bio->read_disk; | |
1373 | int success = 0; | |
1374 | mdk_rdev_t *rdev; | |
1375 | ||
1376 | if (s > (PAGE_SIZE>>9)) | |
1377 | s = PAGE_SIZE >> 9; | |
1378 | do { | |
1379 | if (r1_bio->bios[d]->bi_end_io == end_sync_read) { | |
ddac7c7e N |
1380 | /* No rcu protection needed here devices |
1381 | * can only be removed when no resync is | |
1382 | * active, and resync is currently active | |
1383 | */ | |
69382e85 N |
1384 | rdev = conf->mirrors[d].rdev; |
1385 | if (sync_page_io(rdev->bdev, | |
1386 | sect + rdev->data_offset, | |
1387 | s<<9, | |
1388 | bio->bi_io_vec[idx].bv_page, | |
1389 | READ)) { | |
1390 | success = 1; | |
1391 | break; | |
1392 | } | |
1393 | } | |
1394 | d++; | |
1395 | if (d == conf->raid_disks) | |
1396 | d = 0; | |
1397 | } while (!success && d != r1_bio->read_disk); | |
1398 | ||
1399 | if (success) { | |
097426f6 | 1400 | int start = d; |
69382e85 N |
1401 | /* write it back and re-read */ |
1402 | set_bit(R1BIO_Uptodate, &r1_bio->state); | |
1403 | while (d != r1_bio->read_disk) { | |
1404 | if (d == 0) | |
1405 | d = conf->raid_disks; | |
1406 | d--; | |
1407 | if (r1_bio->bios[d]->bi_end_io != end_sync_read) | |
1408 | continue; | |
1409 | rdev = conf->mirrors[d].rdev; | |
4dbcdc75 | 1410 | atomic_add(s, &rdev->corrected_errors); |
69382e85 N |
1411 | if (sync_page_io(rdev->bdev, |
1412 | sect + rdev->data_offset, | |
1413 | s<<9, | |
1414 | bio->bi_io_vec[idx].bv_page, | |
097426f6 N |
1415 | WRITE) == 0) |
1416 | md_error(mddev, rdev); | |
1417 | } | |
1418 | d = start; | |
1419 | while (d != r1_bio->read_disk) { | |
1420 | if (d == 0) | |
1421 | d = conf->raid_disks; | |
1422 | d--; | |
1423 | if (r1_bio->bios[d]->bi_end_io != end_sync_read) | |
1424 | continue; | |
1425 | rdev = conf->mirrors[d].rdev; | |
1426 | if (sync_page_io(rdev->bdev, | |
69382e85 N |
1427 | sect + rdev->data_offset, |
1428 | s<<9, | |
1429 | bio->bi_io_vec[idx].bv_page, | |
097426f6 | 1430 | READ) == 0) |
69382e85 | 1431 | md_error(mddev, rdev); |
69382e85 N |
1432 | } |
1433 | } else { | |
1434 | char b[BDEVNAME_SIZE]; | |
1435 | /* Cannot read from anywhere, array is toast */ | |
1436 | md_error(mddev, conf->mirrors[r1_bio->read_disk].rdev); | |
9dd1e2fa | 1437 | printk(KERN_ALERT "md/raid1:%s: %s: unrecoverable I/O read error" |
69382e85 | 1438 | " for block %llu\n", |
9dd1e2fa N |
1439 | mdname(mddev), |
1440 | bdevname(bio->bi_bdev, b), | |
69382e85 N |
1441 | (unsigned long long)r1_bio->sector); |
1442 | md_done_sync(mddev, r1_bio->sectors, 0); | |
1443 | put_buf(r1_bio); | |
1444 | return; | |
1445 | } | |
1446 | sectors -= s; | |
1447 | sect += s; | |
1448 | idx ++; | |
1449 | } | |
1da177e4 | 1450 | } |
d11c171e N |
1451 | |
1452 | /* | |
1453 | * schedule writes | |
1454 | */ | |
1da177e4 LT |
1455 | atomic_set(&r1_bio->remaining, 1); |
1456 | for (i = 0; i < disks ; i++) { | |
1457 | wbio = r1_bio->bios[i]; | |
3e198f78 N |
1458 | if (wbio->bi_end_io == NULL || |
1459 | (wbio->bi_end_io == end_sync_read && | |
1460 | (i == r1_bio->read_disk || | |
1461 | !test_bit(MD_RECOVERY_SYNC, &mddev->recovery)))) | |
1da177e4 LT |
1462 | continue; |
1463 | ||
3e198f78 N |
1464 | wbio->bi_rw = WRITE; |
1465 | wbio->bi_end_io = end_sync_write; | |
1da177e4 LT |
1466 | atomic_inc(&r1_bio->remaining); |
1467 | md_sync_acct(conf->mirrors[i].rdev->bdev, wbio->bi_size >> 9); | |
191ea9b2 | 1468 | |
1da177e4 LT |
1469 | generic_make_request(wbio); |
1470 | } | |
1471 | ||
1472 | if (atomic_dec_and_test(&r1_bio->remaining)) { | |
191ea9b2 | 1473 | /* if we're here, all write(s) have completed, so clean up */ |
1da177e4 LT |
1474 | md_done_sync(mddev, r1_bio->sectors, 1); |
1475 | put_buf(r1_bio); | |
1476 | } | |
1477 | } | |
1478 | ||
1479 | /* | |
1480 | * This is a kernel thread which: | |
1481 | * | |
1482 | * 1. Retries failed read operations on working mirrors. | |
1483 | * 2. Updates the raid superblock when problems encounter. | |
1484 | * 3. Performs writes following reads for array syncronising. | |
1485 | */ | |
1486 | ||
867868fb N |
1487 | static void fix_read_error(conf_t *conf, int read_disk, |
1488 | sector_t sect, int sectors) | |
1489 | { | |
1490 | mddev_t *mddev = conf->mddev; | |
1491 | while(sectors) { | |
1492 | int s = sectors; | |
1493 | int d = read_disk; | |
1494 | int success = 0; | |
1495 | int start; | |
1496 | mdk_rdev_t *rdev; | |
1497 | ||
1498 | if (s > (PAGE_SIZE>>9)) | |
1499 | s = PAGE_SIZE >> 9; | |
1500 | ||
1501 | do { | |
1502 | /* Note: no rcu protection needed here | |
1503 | * as this is synchronous in the raid1d thread | |
1504 | * which is the thread that might remove | |
1505 | * a device. If raid1d ever becomes multi-threaded.... | |
1506 | */ | |
1507 | rdev = conf->mirrors[d].rdev; | |
1508 | if (rdev && | |
1509 | test_bit(In_sync, &rdev->flags) && | |
1510 | sync_page_io(rdev->bdev, | |
1511 | sect + rdev->data_offset, | |
1512 | s<<9, | |
1513 | conf->tmppage, READ)) | |
1514 | success = 1; | |
1515 | else { | |
1516 | d++; | |
1517 | if (d == conf->raid_disks) | |
1518 | d = 0; | |
1519 | } | |
1520 | } while (!success && d != read_disk); | |
1521 | ||
1522 | if (!success) { | |
1523 | /* Cannot read from anywhere -- bye bye array */ | |
1524 | md_error(mddev, conf->mirrors[read_disk].rdev); | |
1525 | break; | |
1526 | } | |
1527 | /* write it back and re-read */ | |
1528 | start = d; | |
1529 | while (d != read_disk) { | |
1530 | if (d==0) | |
1531 | d = conf->raid_disks; | |
1532 | d--; | |
1533 | rdev = conf->mirrors[d].rdev; | |
1534 | if (rdev && | |
1535 | test_bit(In_sync, &rdev->flags)) { | |
1536 | if (sync_page_io(rdev->bdev, | |
1537 | sect + rdev->data_offset, | |
1538 | s<<9, conf->tmppage, WRITE) | |
1539 | == 0) | |
1540 | /* Well, this device is dead */ | |
1541 | md_error(mddev, rdev); | |
1542 | } | |
1543 | } | |
1544 | d = start; | |
1545 | while (d != read_disk) { | |
1546 | char b[BDEVNAME_SIZE]; | |
1547 | if (d==0) | |
1548 | d = conf->raid_disks; | |
1549 | d--; | |
1550 | rdev = conf->mirrors[d].rdev; | |
1551 | if (rdev && | |
1552 | test_bit(In_sync, &rdev->flags)) { | |
1553 | if (sync_page_io(rdev->bdev, | |
1554 | sect + rdev->data_offset, | |
1555 | s<<9, conf->tmppage, READ) | |
1556 | == 0) | |
1557 | /* Well, this device is dead */ | |
1558 | md_error(mddev, rdev); | |
1559 | else { | |
1560 | atomic_add(s, &rdev->corrected_errors); | |
1561 | printk(KERN_INFO | |
9dd1e2fa | 1562 | "md/raid1:%s: read error corrected " |
867868fb N |
1563 | "(%d sectors at %llu on %s)\n", |
1564 | mdname(mddev), s, | |
969b755a RD |
1565 | (unsigned long long)(sect + |
1566 | rdev->data_offset), | |
867868fb N |
1567 | bdevname(rdev->bdev, b)); |
1568 | } | |
1569 | } | |
1570 | } | |
1571 | sectors -= s; | |
1572 | sect += s; | |
1573 | } | |
1574 | } | |
1575 | ||
1da177e4 LT |
1576 | static void raid1d(mddev_t *mddev) |
1577 | { | |
1578 | r1bio_t *r1_bio; | |
1579 | struct bio *bio; | |
1580 | unsigned long flags; | |
070ec55d | 1581 | conf_t *conf = mddev->private; |
1da177e4 LT |
1582 | struct list_head *head = &conf->retry_list; |
1583 | int unplug=0; | |
1584 | mdk_rdev_t *rdev; | |
1585 | ||
1586 | md_check_recovery(mddev); | |
1da177e4 LT |
1587 | |
1588 | for (;;) { | |
1589 | char b[BDEVNAME_SIZE]; | |
191ea9b2 | 1590 | |
a35e63ef | 1591 | unplug += flush_pending_writes(conf); |
191ea9b2 | 1592 | |
a35e63ef N |
1593 | spin_lock_irqsave(&conf->device_lock, flags); |
1594 | if (list_empty(head)) { | |
1595 | spin_unlock_irqrestore(&conf->device_lock, flags); | |
1da177e4 | 1596 | break; |
a35e63ef | 1597 | } |
1da177e4 LT |
1598 | r1_bio = list_entry(head->prev, r1bio_t, retry_list); |
1599 | list_del(head->prev); | |
ddaf22ab | 1600 | conf->nr_queued--; |
1da177e4 LT |
1601 | spin_unlock_irqrestore(&conf->device_lock, flags); |
1602 | ||
1603 | mddev = r1_bio->mddev; | |
070ec55d | 1604 | conf = mddev->private; |
1da177e4 LT |
1605 | if (test_bit(R1BIO_IsSync, &r1_bio->state)) { |
1606 | sync_request_write(mddev, r1_bio); | |
1607 | unplug = 1; | |
1608 | } else { | |
1609 | int disk; | |
ddaf22ab N |
1610 | |
1611 | /* we got a read error. Maybe the drive is bad. Maybe just | |
1612 | * the block and we can fix it. | |
1613 | * We freeze all other IO, and try reading the block from | |
1614 | * other devices. When we find one, we re-write | |
1615 | * and check it that fixes the read error. | |
1616 | * This is all done synchronously while the array is | |
1617 | * frozen | |
1618 | */ | |
867868fb N |
1619 | if (mddev->ro == 0) { |
1620 | freeze_array(conf); | |
1621 | fix_read_error(conf, r1_bio->read_disk, | |
1622 | r1_bio->sector, | |
1623 | r1_bio->sectors); | |
1624 | unfreeze_array(conf); | |
d0e26078 N |
1625 | } else |
1626 | md_error(mddev, | |
1627 | conf->mirrors[r1_bio->read_disk].rdev); | |
ddaf22ab | 1628 | |
1da177e4 | 1629 | bio = r1_bio->bios[r1_bio->read_disk]; |
d0e26078 | 1630 | if ((disk=read_balance(conf, r1_bio)) == -1) { |
9dd1e2fa | 1631 | printk(KERN_ALERT "md/raid1:%s: %s: unrecoverable I/O" |
1da177e4 | 1632 | " read error for block %llu\n", |
9dd1e2fa | 1633 | mdname(mddev), |
1da177e4 LT |
1634 | bdevname(bio->bi_bdev,b), |
1635 | (unsigned long long)r1_bio->sector); | |
1636 | raid_end_bio_io(r1_bio); | |
1637 | } else { | |
2c7d46ec | 1638 | const unsigned long do_sync = r1_bio->master_bio->bi_rw & REQ_SYNC; |
cf30a473 N |
1639 | r1_bio->bios[r1_bio->read_disk] = |
1640 | mddev->ro ? IO_BLOCKED : NULL; | |
1da177e4 LT |
1641 | r1_bio->read_disk = disk; |
1642 | bio_put(bio); | |
1643 | bio = bio_clone(r1_bio->master_bio, GFP_NOIO); | |
1644 | r1_bio->bios[r1_bio->read_disk] = bio; | |
1645 | rdev = conf->mirrors[disk].rdev; | |
1646 | if (printk_ratelimit()) | |
9dd1e2fa | 1647 | printk(KERN_ERR "md/raid1:%s: redirecting sector %llu to" |
d754c5ae | 1648 | " other mirror: %s\n", |
9dd1e2fa | 1649 | mdname(mddev), |
d754c5ae N |
1650 | (unsigned long long)r1_bio->sector, |
1651 | bdevname(rdev->bdev,b)); | |
1da177e4 LT |
1652 | bio->bi_sector = r1_bio->sector + rdev->data_offset; |
1653 | bio->bi_bdev = rdev->bdev; | |
1654 | bio->bi_end_io = raid1_end_read_request; | |
7b6d91da | 1655 | bio->bi_rw = READ | do_sync; |
1da177e4 LT |
1656 | bio->bi_private = r1_bio; |
1657 | unplug = 1; | |
1658 | generic_make_request(bio); | |
1659 | } | |
1660 | } | |
1d9d5241 | 1661 | cond_resched(); |
1da177e4 | 1662 | } |
1da177e4 LT |
1663 | if (unplug) |
1664 | unplug_slaves(mddev); | |
1665 | } | |
1666 | ||
1667 | ||
1668 | static int init_resync(conf_t *conf) | |
1669 | { | |
1670 | int buffs; | |
1671 | ||
1672 | buffs = RESYNC_WINDOW / RESYNC_BLOCK_SIZE; | |
9e77c485 | 1673 | BUG_ON(conf->r1buf_pool); |
1da177e4 LT |
1674 | conf->r1buf_pool = mempool_create(buffs, r1buf_pool_alloc, r1buf_pool_free, |
1675 | conf->poolinfo); | |
1676 | if (!conf->r1buf_pool) | |
1677 | return -ENOMEM; | |
1678 | conf->next_resync = 0; | |
1679 | return 0; | |
1680 | } | |
1681 | ||
1682 | /* | |
1683 | * perform a "sync" on one "block" | |
1684 | * | |
1685 | * We need to make sure that no normal I/O request - particularly write | |
1686 | * requests - conflict with active sync requests. | |
1687 | * | |
1688 | * This is achieved by tracking pending requests and a 'barrier' concept | |
1689 | * that can be installed to exclude normal IO requests. | |
1690 | */ | |
1691 | ||
57afd89f | 1692 | static sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, int go_faster) |
1da177e4 | 1693 | { |
070ec55d | 1694 | conf_t *conf = mddev->private; |
1da177e4 LT |
1695 | r1bio_t *r1_bio; |
1696 | struct bio *bio; | |
1697 | sector_t max_sector, nr_sectors; | |
3e198f78 | 1698 | int disk = -1; |
1da177e4 | 1699 | int i; |
3e198f78 N |
1700 | int wonly = -1; |
1701 | int write_targets = 0, read_targets = 0; | |
57dab0bd | 1702 | sector_t sync_blocks; |
e3b9703e | 1703 | int still_degraded = 0; |
1da177e4 LT |
1704 | |
1705 | if (!conf->r1buf_pool) | |
1706 | if (init_resync(conf)) | |
57afd89f | 1707 | return 0; |
1da177e4 | 1708 | |
58c0fed4 | 1709 | max_sector = mddev->dev_sectors; |
1da177e4 | 1710 | if (sector_nr >= max_sector) { |
191ea9b2 N |
1711 | /* If we aborted, we need to abort the |
1712 | * sync on the 'current' bitmap chunk (there will | |
1713 | * only be one in raid1 resync. | |
1714 | * We can find the current addess in mddev->curr_resync | |
1715 | */ | |
6a806c51 N |
1716 | if (mddev->curr_resync < max_sector) /* aborted */ |
1717 | bitmap_end_sync(mddev->bitmap, mddev->curr_resync, | |
191ea9b2 | 1718 | &sync_blocks, 1); |
6a806c51 | 1719 | else /* completed sync */ |
191ea9b2 | 1720 | conf->fullsync = 0; |
6a806c51 N |
1721 | |
1722 | bitmap_close_sync(mddev->bitmap); | |
1da177e4 LT |
1723 | close_sync(conf); |
1724 | return 0; | |
1725 | } | |
1726 | ||
07d84d10 N |
1727 | if (mddev->bitmap == NULL && |
1728 | mddev->recovery_cp == MaxSector && | |
6394cca5 | 1729 | !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) && |
07d84d10 N |
1730 | conf->fullsync == 0) { |
1731 | *skipped = 1; | |
1732 | return max_sector - sector_nr; | |
1733 | } | |
6394cca5 N |
1734 | /* before building a request, check if we can skip these blocks.. |
1735 | * This call the bitmap_start_sync doesn't actually record anything | |
1736 | */ | |
e3b9703e | 1737 | if (!bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, 1) && |
e5de485f | 1738 | !conf->fullsync && !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) { |
191ea9b2 N |
1739 | /* We can skip this block, and probably several more */ |
1740 | *skipped = 1; | |
1741 | return sync_blocks; | |
1742 | } | |
1da177e4 | 1743 | /* |
17999be4 N |
1744 | * If there is non-resync activity waiting for a turn, |
1745 | * and resync is going fast enough, | |
1746 | * then let it though before starting on this new sync request. | |
1da177e4 | 1747 | */ |
17999be4 | 1748 | if (!go_faster && conf->nr_waiting) |
1da177e4 | 1749 | msleep_interruptible(1000); |
17999be4 | 1750 | |
b47490c9 | 1751 | bitmap_cond_end_sync(mddev->bitmap, sector_nr); |
1c4588e9 | 1752 | r1_bio = mempool_alloc(conf->r1buf_pool, GFP_NOIO); |
17999be4 N |
1753 | raise_barrier(conf); |
1754 | ||
1755 | conf->next_resync = sector_nr; | |
1da177e4 | 1756 | |
3e198f78 | 1757 | rcu_read_lock(); |
1da177e4 | 1758 | /* |
3e198f78 N |
1759 | * If we get a correctably read error during resync or recovery, |
1760 | * we might want to read from a different device. So we | |
1761 | * flag all drives that could conceivably be read from for READ, | |
1762 | * and any others (which will be non-In_sync devices) for WRITE. | |
1763 | * If a read fails, we try reading from something else for which READ | |
1764 | * is OK. | |
1da177e4 | 1765 | */ |
1da177e4 | 1766 | |
1da177e4 LT |
1767 | r1_bio->mddev = mddev; |
1768 | r1_bio->sector = sector_nr; | |
191ea9b2 | 1769 | r1_bio->state = 0; |
1da177e4 | 1770 | set_bit(R1BIO_IsSync, &r1_bio->state); |
1da177e4 LT |
1771 | |
1772 | for (i=0; i < conf->raid_disks; i++) { | |
3e198f78 | 1773 | mdk_rdev_t *rdev; |
1da177e4 LT |
1774 | bio = r1_bio->bios[i]; |
1775 | ||
1776 | /* take from bio_init */ | |
1777 | bio->bi_next = NULL; | |
db8d9d35 | 1778 | bio->bi_flags &= ~(BIO_POOL_MASK-1); |
1da177e4 | 1779 | bio->bi_flags |= 1 << BIO_UPTODATE; |
db8d9d35 | 1780 | bio->bi_comp_cpu = -1; |
802ba064 | 1781 | bio->bi_rw = READ; |
1da177e4 LT |
1782 | bio->bi_vcnt = 0; |
1783 | bio->bi_idx = 0; | |
1784 | bio->bi_phys_segments = 0; | |
1da177e4 LT |
1785 | bio->bi_size = 0; |
1786 | bio->bi_end_io = NULL; | |
1787 | bio->bi_private = NULL; | |
1788 | ||
3e198f78 N |
1789 | rdev = rcu_dereference(conf->mirrors[i].rdev); |
1790 | if (rdev == NULL || | |
1791 | test_bit(Faulty, &rdev->flags)) { | |
e3b9703e N |
1792 | still_degraded = 1; |
1793 | continue; | |
3e198f78 | 1794 | } else if (!test_bit(In_sync, &rdev->flags)) { |
1da177e4 LT |
1795 | bio->bi_rw = WRITE; |
1796 | bio->bi_end_io = end_sync_write; | |
1797 | write_targets ++; | |
3e198f78 N |
1798 | } else { |
1799 | /* may need to read from here */ | |
1800 | bio->bi_rw = READ; | |
1801 | bio->bi_end_io = end_sync_read; | |
1802 | if (test_bit(WriteMostly, &rdev->flags)) { | |
1803 | if (wonly < 0) | |
1804 | wonly = i; | |
1805 | } else { | |
1806 | if (disk < 0) | |
1807 | disk = i; | |
1808 | } | |
1809 | read_targets++; | |
1810 | } | |
1811 | atomic_inc(&rdev->nr_pending); | |
1812 | bio->bi_sector = sector_nr + rdev->data_offset; | |
1813 | bio->bi_bdev = rdev->bdev; | |
1da177e4 LT |
1814 | bio->bi_private = r1_bio; |
1815 | } | |
3e198f78 N |
1816 | rcu_read_unlock(); |
1817 | if (disk < 0) | |
1818 | disk = wonly; | |
1819 | r1_bio->read_disk = disk; | |
191ea9b2 | 1820 | |
3e198f78 N |
1821 | if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) && read_targets > 0) |
1822 | /* extra read targets are also write targets */ | |
1823 | write_targets += read_targets-1; | |
1824 | ||
1825 | if (write_targets == 0 || read_targets == 0) { | |
1da177e4 LT |
1826 | /* There is nowhere to write, so all non-sync |
1827 | * drives must be failed - so we are finished | |
1828 | */ | |
57afd89f N |
1829 | sector_t rv = max_sector - sector_nr; |
1830 | *skipped = 1; | |
1da177e4 | 1831 | put_buf(r1_bio); |
1da177e4 LT |
1832 | return rv; |
1833 | } | |
1834 | ||
c6207277 N |
1835 | if (max_sector > mddev->resync_max) |
1836 | max_sector = mddev->resync_max; /* Don't do IO beyond here */ | |
1da177e4 | 1837 | nr_sectors = 0; |
289e99e8 | 1838 | sync_blocks = 0; |
1da177e4 LT |
1839 | do { |
1840 | struct page *page; | |
1841 | int len = PAGE_SIZE; | |
1842 | if (sector_nr + (len>>9) > max_sector) | |
1843 | len = (max_sector - sector_nr) << 9; | |
1844 | if (len == 0) | |
1845 | break; | |
6a806c51 N |
1846 | if (sync_blocks == 0) { |
1847 | if (!bitmap_start_sync(mddev->bitmap, sector_nr, | |
e5de485f N |
1848 | &sync_blocks, still_degraded) && |
1849 | !conf->fullsync && | |
1850 | !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) | |
6a806c51 | 1851 | break; |
9e77c485 | 1852 | BUG_ON(sync_blocks < (PAGE_SIZE>>9)); |
7571ae88 | 1853 | if ((len >> 9) > sync_blocks) |
6a806c51 | 1854 | len = sync_blocks<<9; |
ab7a30c7 | 1855 | } |
191ea9b2 | 1856 | |
1da177e4 LT |
1857 | for (i=0 ; i < conf->raid_disks; i++) { |
1858 | bio = r1_bio->bios[i]; | |
1859 | if (bio->bi_end_io) { | |
d11c171e | 1860 | page = bio->bi_io_vec[bio->bi_vcnt].bv_page; |
1da177e4 LT |
1861 | if (bio_add_page(bio, page, len, 0) == 0) { |
1862 | /* stop here */ | |
d11c171e | 1863 | bio->bi_io_vec[bio->bi_vcnt].bv_page = page; |
1da177e4 LT |
1864 | while (i > 0) { |
1865 | i--; | |
1866 | bio = r1_bio->bios[i]; | |
6a806c51 N |
1867 | if (bio->bi_end_io==NULL) |
1868 | continue; | |
1da177e4 LT |
1869 | /* remove last page from this bio */ |
1870 | bio->bi_vcnt--; | |
1871 | bio->bi_size -= len; | |
1872 | bio->bi_flags &= ~(1<< BIO_SEG_VALID); | |
1873 | } | |
1874 | goto bio_full; | |
1875 | } | |
1876 | } | |
1877 | } | |
1878 | nr_sectors += len>>9; | |
1879 | sector_nr += len>>9; | |
191ea9b2 | 1880 | sync_blocks -= (len>>9); |
1da177e4 LT |
1881 | } while (r1_bio->bios[disk]->bi_vcnt < RESYNC_PAGES); |
1882 | bio_full: | |
1da177e4 LT |
1883 | r1_bio->sectors = nr_sectors; |
1884 | ||
d11c171e N |
1885 | /* For a user-requested sync, we read all readable devices and do a |
1886 | * compare | |
1887 | */ | |
1888 | if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) { | |
1889 | atomic_set(&r1_bio->remaining, read_targets); | |
1890 | for (i=0; i<conf->raid_disks; i++) { | |
1891 | bio = r1_bio->bios[i]; | |
1892 | if (bio->bi_end_io == end_sync_read) { | |
ddac7c7e | 1893 | md_sync_acct(bio->bi_bdev, nr_sectors); |
d11c171e N |
1894 | generic_make_request(bio); |
1895 | } | |
1896 | } | |
1897 | } else { | |
1898 | atomic_set(&r1_bio->remaining, 1); | |
1899 | bio = r1_bio->bios[r1_bio->read_disk]; | |
ddac7c7e | 1900 | md_sync_acct(bio->bi_bdev, nr_sectors); |
d11c171e | 1901 | generic_make_request(bio); |
1da177e4 | 1902 | |
d11c171e | 1903 | } |
1da177e4 LT |
1904 | return nr_sectors; |
1905 | } | |
1906 | ||
80c3a6ce DW |
1907 | static sector_t raid1_size(mddev_t *mddev, sector_t sectors, int raid_disks) |
1908 | { | |
1909 | if (sectors) | |
1910 | return sectors; | |
1911 | ||
1912 | return mddev->dev_sectors; | |
1913 | } | |
1914 | ||
709ae487 | 1915 | static conf_t *setup_conf(mddev_t *mddev) |
1da177e4 LT |
1916 | { |
1917 | conf_t *conf; | |
709ae487 | 1918 | int i; |
1da177e4 LT |
1919 | mirror_info_t *disk; |
1920 | mdk_rdev_t *rdev; | |
709ae487 | 1921 | int err = -ENOMEM; |
1da177e4 | 1922 | |
9ffae0cf | 1923 | conf = kzalloc(sizeof(conf_t), GFP_KERNEL); |
1da177e4 | 1924 | if (!conf) |
709ae487 | 1925 | goto abort; |
1da177e4 | 1926 | |
9ffae0cf | 1927 | conf->mirrors = kzalloc(sizeof(struct mirror_info)*mddev->raid_disks, |
1da177e4 LT |
1928 | GFP_KERNEL); |
1929 | if (!conf->mirrors) | |
709ae487 | 1930 | goto abort; |
1da177e4 | 1931 | |
ddaf22ab N |
1932 | conf->tmppage = alloc_page(GFP_KERNEL); |
1933 | if (!conf->tmppage) | |
709ae487 | 1934 | goto abort; |
ddaf22ab | 1935 | |
709ae487 | 1936 | conf->poolinfo = kzalloc(sizeof(*conf->poolinfo), GFP_KERNEL); |
1da177e4 | 1937 | if (!conf->poolinfo) |
709ae487 | 1938 | goto abort; |
1da177e4 LT |
1939 | conf->poolinfo->raid_disks = mddev->raid_disks; |
1940 | conf->r1bio_pool = mempool_create(NR_RAID1_BIOS, r1bio_pool_alloc, | |
1941 | r1bio_pool_free, | |
1942 | conf->poolinfo); | |
1943 | if (!conf->r1bio_pool) | |
709ae487 N |
1944 | goto abort; |
1945 | ||
ed9bfdf1 | 1946 | conf->poolinfo->mddev = mddev; |
1da177e4 | 1947 | |
e7e72bf6 | 1948 | spin_lock_init(&conf->device_lock); |
159ec1fc | 1949 | list_for_each_entry(rdev, &mddev->disks, same_set) { |
709ae487 | 1950 | int disk_idx = rdev->raid_disk; |
1da177e4 LT |
1951 | if (disk_idx >= mddev->raid_disks |
1952 | || disk_idx < 0) | |
1953 | continue; | |
1954 | disk = conf->mirrors + disk_idx; | |
1955 | ||
1956 | disk->rdev = rdev; | |
1da177e4 LT |
1957 | |
1958 | disk->head_position = 0; | |
1da177e4 LT |
1959 | } |
1960 | conf->raid_disks = mddev->raid_disks; | |
1961 | conf->mddev = mddev; | |
1da177e4 | 1962 | INIT_LIST_HEAD(&conf->retry_list); |
1da177e4 LT |
1963 | |
1964 | spin_lock_init(&conf->resync_lock); | |
17999be4 | 1965 | init_waitqueue_head(&conf->wait_barrier); |
1da177e4 | 1966 | |
191ea9b2 N |
1967 | bio_list_init(&conf->pending_bio_list); |
1968 | bio_list_init(&conf->flushing_bio_list); | |
1969 | ||
709ae487 | 1970 | conf->last_used = -1; |
1da177e4 LT |
1971 | for (i = 0; i < conf->raid_disks; i++) { |
1972 | ||
1973 | disk = conf->mirrors + i; | |
1974 | ||
5fd6c1dc N |
1975 | if (!disk->rdev || |
1976 | !test_bit(In_sync, &disk->rdev->flags)) { | |
1da177e4 | 1977 | disk->head_position = 0; |
918f0238 N |
1978 | if (disk->rdev) |
1979 | conf->fullsync = 1; | |
709ae487 N |
1980 | } else if (conf->last_used < 0) |
1981 | /* | |
1982 | * The first working device is used as a | |
1983 | * starting point to read balancing. | |
1984 | */ | |
1985 | conf->last_used = i; | |
1da177e4 | 1986 | } |
709ae487 N |
1987 | |
1988 | err = -EIO; | |
1989 | if (conf->last_used < 0) { | |
9dd1e2fa | 1990 | printk(KERN_ERR "md/raid1:%s: no operational mirrors\n", |
709ae487 N |
1991 | mdname(mddev)); |
1992 | goto abort; | |
1993 | } | |
1994 | err = -ENOMEM; | |
1995 | conf->thread = md_register_thread(raid1d, mddev, NULL); | |
1996 | if (!conf->thread) { | |
1997 | printk(KERN_ERR | |
9dd1e2fa | 1998 | "md/raid1:%s: couldn't allocate thread\n", |
709ae487 N |
1999 | mdname(mddev)); |
2000 | goto abort; | |
11ce99e6 | 2001 | } |
1da177e4 | 2002 | |
709ae487 N |
2003 | return conf; |
2004 | ||
2005 | abort: | |
2006 | if (conf) { | |
2007 | if (conf->r1bio_pool) | |
2008 | mempool_destroy(conf->r1bio_pool); | |
2009 | kfree(conf->mirrors); | |
2010 | safe_put_page(conf->tmppage); | |
2011 | kfree(conf->poolinfo); | |
2012 | kfree(conf); | |
2013 | } | |
2014 | return ERR_PTR(err); | |
2015 | } | |
2016 | ||
2017 | static int run(mddev_t *mddev) | |
2018 | { | |
2019 | conf_t *conf; | |
2020 | int i; | |
2021 | mdk_rdev_t *rdev; | |
2022 | ||
2023 | if (mddev->level != 1) { | |
9dd1e2fa | 2024 | printk(KERN_ERR "md/raid1:%s: raid level not set to mirroring (%d)\n", |
709ae487 N |
2025 | mdname(mddev), mddev->level); |
2026 | return -EIO; | |
2027 | } | |
2028 | if (mddev->reshape_position != MaxSector) { | |
9dd1e2fa | 2029 | printk(KERN_ERR "md/raid1:%s: reshape_position set but not supported\n", |
709ae487 N |
2030 | mdname(mddev)); |
2031 | return -EIO; | |
2032 | } | |
1da177e4 | 2033 | /* |
709ae487 N |
2034 | * copy the already verified devices into our private RAID1 |
2035 | * bookkeeping area. [whatever we allocate in run(), | |
2036 | * should be freed in stop()] | |
1da177e4 | 2037 | */ |
709ae487 N |
2038 | if (mddev->private == NULL) |
2039 | conf = setup_conf(mddev); | |
2040 | else | |
2041 | conf = mddev->private; | |
1da177e4 | 2042 | |
709ae487 N |
2043 | if (IS_ERR(conf)) |
2044 | return PTR_ERR(conf); | |
1da177e4 | 2045 | |
709ae487 N |
2046 | mddev->queue->queue_lock = &conf->device_lock; |
2047 | list_for_each_entry(rdev, &mddev->disks, same_set) { | |
2048 | disk_stack_limits(mddev->gendisk, rdev->bdev, | |
2049 | rdev->data_offset << 9); | |
2050 | /* as we don't honour merge_bvec_fn, we must never risk | |
627a2d3c N |
2051 | * violating it, so limit ->max_segments to 1 lying within |
2052 | * a single page, as a one page request is never in violation. | |
709ae487 | 2053 | */ |
627a2d3c N |
2054 | if (rdev->bdev->bd_disk->queue->merge_bvec_fn) { |
2055 | blk_queue_max_segments(mddev->queue, 1); | |
2056 | blk_queue_segment_boundary(mddev->queue, | |
2057 | PAGE_CACHE_SIZE - 1); | |
2058 | } | |
1da177e4 | 2059 | } |
191ea9b2 | 2060 | |
709ae487 N |
2061 | mddev->degraded = 0; |
2062 | for (i=0; i < conf->raid_disks; i++) | |
2063 | if (conf->mirrors[i].rdev == NULL || | |
2064 | !test_bit(In_sync, &conf->mirrors[i].rdev->flags) || | |
2065 | test_bit(Faulty, &conf->mirrors[i].rdev->flags)) | |
2066 | mddev->degraded++; | |
2067 | ||
2068 | if (conf->raid_disks - mddev->degraded == 1) | |
2069 | mddev->recovery_cp = MaxSector; | |
2070 | ||
8c6ac868 | 2071 | if (mddev->recovery_cp != MaxSector) |
9dd1e2fa | 2072 | printk(KERN_NOTICE "md/raid1:%s: not clean" |
8c6ac868 AN |
2073 | " -- starting background reconstruction\n", |
2074 | mdname(mddev)); | |
1da177e4 | 2075 | printk(KERN_INFO |
9dd1e2fa | 2076 | "md/raid1:%s: active with %d out of %d mirrors\n", |
1da177e4 LT |
2077 | mdname(mddev), mddev->raid_disks - mddev->degraded, |
2078 | mddev->raid_disks); | |
709ae487 | 2079 | |
1da177e4 LT |
2080 | /* |
2081 | * Ok, everything is just fine now | |
2082 | */ | |
709ae487 N |
2083 | mddev->thread = conf->thread; |
2084 | conf->thread = NULL; | |
2085 | mddev->private = conf; | |
2086 | ||
1f403624 | 2087 | md_set_array_sectors(mddev, raid1_size(mddev, 0, 0)); |
1da177e4 | 2088 | |
7a5febe9 | 2089 | mddev->queue->unplug_fn = raid1_unplug; |
0d129228 N |
2090 | mddev->queue->backing_dev_info.congested_fn = raid1_congested; |
2091 | mddev->queue->backing_dev_info.congested_data = mddev; | |
ac5e7113 | 2092 | md_integrity_register(mddev); |
1da177e4 | 2093 | return 0; |
1da177e4 LT |
2094 | } |
2095 | ||
2096 | static int stop(mddev_t *mddev) | |
2097 | { | |
070ec55d | 2098 | conf_t *conf = mddev->private; |
4b6d287f | 2099 | struct bitmap *bitmap = mddev->bitmap; |
4b6d287f N |
2100 | |
2101 | /* wait for behind writes to complete */ | |
e555190d | 2102 | if (bitmap && atomic_read(&bitmap->behind_writes) > 0) { |
9dd1e2fa N |
2103 | printk(KERN_INFO "md/raid1:%s: behind writes in progress - waiting to stop.\n", |
2104 | mdname(mddev)); | |
4b6d287f | 2105 | /* need to kick something here to make sure I/O goes? */ |
e555190d N |
2106 | wait_event(bitmap->behind_wait, |
2107 | atomic_read(&bitmap->behind_writes) == 0); | |
4b6d287f | 2108 | } |
1da177e4 | 2109 | |
409c57f3 N |
2110 | raise_barrier(conf); |
2111 | lower_barrier(conf); | |
2112 | ||
1da177e4 LT |
2113 | md_unregister_thread(mddev->thread); |
2114 | mddev->thread = NULL; | |
2115 | blk_sync_queue(mddev->queue); /* the unplug fn references 'conf'*/ | |
2116 | if (conf->r1bio_pool) | |
2117 | mempool_destroy(conf->r1bio_pool); | |
990a8baf JJ |
2118 | kfree(conf->mirrors); |
2119 | kfree(conf->poolinfo); | |
1da177e4 LT |
2120 | kfree(conf); |
2121 | mddev->private = NULL; | |
2122 | return 0; | |
2123 | } | |
2124 | ||
2125 | static int raid1_resize(mddev_t *mddev, sector_t sectors) | |
2126 | { | |
2127 | /* no resync is happening, and there is enough space | |
2128 | * on all devices, so we can resize. | |
2129 | * We need to make sure resync covers any new space. | |
2130 | * If the array is shrinking we should possibly wait until | |
2131 | * any io in the removed space completes, but it hardly seems | |
2132 | * worth it. | |
2133 | */ | |
1f403624 | 2134 | md_set_array_sectors(mddev, raid1_size(mddev, sectors, 0)); |
b522adcd DW |
2135 | if (mddev->array_sectors > raid1_size(mddev, sectors, 0)) |
2136 | return -EINVAL; | |
f233ea5c | 2137 | set_capacity(mddev->gendisk, mddev->array_sectors); |
449aad3e | 2138 | revalidate_disk(mddev->gendisk); |
b522adcd | 2139 | if (sectors > mddev->dev_sectors && |
f233ea5c | 2140 | mddev->recovery_cp == MaxSector) { |
58c0fed4 | 2141 | mddev->recovery_cp = mddev->dev_sectors; |
1da177e4 LT |
2142 | set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); |
2143 | } | |
b522adcd | 2144 | mddev->dev_sectors = sectors; |
4b5c7ae8 | 2145 | mddev->resync_max_sectors = sectors; |
1da177e4 LT |
2146 | return 0; |
2147 | } | |
2148 | ||
63c70c4f | 2149 | static int raid1_reshape(mddev_t *mddev) |
1da177e4 LT |
2150 | { |
2151 | /* We need to: | |
2152 | * 1/ resize the r1bio_pool | |
2153 | * 2/ resize conf->mirrors | |
2154 | * | |
2155 | * We allocate a new r1bio_pool if we can. | |
2156 | * Then raise a device barrier and wait until all IO stops. | |
2157 | * Then resize conf->mirrors and swap in the new r1bio pool. | |
6ea9c07c N |
2158 | * |
2159 | * At the same time, we "pack" the devices so that all the missing | |
2160 | * devices have the higher raid_disk numbers. | |
1da177e4 LT |
2161 | */ |
2162 | mempool_t *newpool, *oldpool; | |
2163 | struct pool_info *newpoolinfo; | |
2164 | mirror_info_t *newmirrors; | |
070ec55d | 2165 | conf_t *conf = mddev->private; |
63c70c4f | 2166 | int cnt, raid_disks; |
c04be0aa | 2167 | unsigned long flags; |
b5470dc5 | 2168 | int d, d2, err; |
1da177e4 | 2169 | |
63c70c4f | 2170 | /* Cannot change chunk_size, layout, or level */ |
664e7c41 | 2171 | if (mddev->chunk_sectors != mddev->new_chunk_sectors || |
63c70c4f N |
2172 | mddev->layout != mddev->new_layout || |
2173 | mddev->level != mddev->new_level) { | |
664e7c41 | 2174 | mddev->new_chunk_sectors = mddev->chunk_sectors; |
63c70c4f N |
2175 | mddev->new_layout = mddev->layout; |
2176 | mddev->new_level = mddev->level; | |
2177 | return -EINVAL; | |
2178 | } | |
2179 | ||
b5470dc5 DW |
2180 | err = md_allow_write(mddev); |
2181 | if (err) | |
2182 | return err; | |
2a2275d6 | 2183 | |
63c70c4f N |
2184 | raid_disks = mddev->raid_disks + mddev->delta_disks; |
2185 | ||
6ea9c07c N |
2186 | if (raid_disks < conf->raid_disks) { |
2187 | cnt=0; | |
2188 | for (d= 0; d < conf->raid_disks; d++) | |
2189 | if (conf->mirrors[d].rdev) | |
2190 | cnt++; | |
2191 | if (cnt > raid_disks) | |
1da177e4 | 2192 | return -EBUSY; |
6ea9c07c | 2193 | } |
1da177e4 LT |
2194 | |
2195 | newpoolinfo = kmalloc(sizeof(*newpoolinfo), GFP_KERNEL); | |
2196 | if (!newpoolinfo) | |
2197 | return -ENOMEM; | |
2198 | newpoolinfo->mddev = mddev; | |
2199 | newpoolinfo->raid_disks = raid_disks; | |
2200 | ||
2201 | newpool = mempool_create(NR_RAID1_BIOS, r1bio_pool_alloc, | |
2202 | r1bio_pool_free, newpoolinfo); | |
2203 | if (!newpool) { | |
2204 | kfree(newpoolinfo); | |
2205 | return -ENOMEM; | |
2206 | } | |
9ffae0cf | 2207 | newmirrors = kzalloc(sizeof(struct mirror_info) * raid_disks, GFP_KERNEL); |
1da177e4 LT |
2208 | if (!newmirrors) { |
2209 | kfree(newpoolinfo); | |
2210 | mempool_destroy(newpool); | |
2211 | return -ENOMEM; | |
2212 | } | |
1da177e4 | 2213 | |
17999be4 | 2214 | raise_barrier(conf); |
1da177e4 LT |
2215 | |
2216 | /* ok, everything is stopped */ | |
2217 | oldpool = conf->r1bio_pool; | |
2218 | conf->r1bio_pool = newpool; | |
6ea9c07c | 2219 | |
a88aa786 N |
2220 | for (d = d2 = 0; d < conf->raid_disks; d++) { |
2221 | mdk_rdev_t *rdev = conf->mirrors[d].rdev; | |
2222 | if (rdev && rdev->raid_disk != d2) { | |
2223 | char nm[20]; | |
2224 | sprintf(nm, "rd%d", rdev->raid_disk); | |
2225 | sysfs_remove_link(&mddev->kobj, nm); | |
2226 | rdev->raid_disk = d2; | |
2227 | sprintf(nm, "rd%d", rdev->raid_disk); | |
2228 | sysfs_remove_link(&mddev->kobj, nm); | |
2229 | if (sysfs_create_link(&mddev->kobj, | |
2230 | &rdev->kobj, nm)) | |
2231 | printk(KERN_WARNING | |
9dd1e2fa N |
2232 | "md/raid1:%s: cannot register " |
2233 | "%s\n", | |
2234 | mdname(mddev), nm); | |
6ea9c07c | 2235 | } |
a88aa786 N |
2236 | if (rdev) |
2237 | newmirrors[d2++].rdev = rdev; | |
2238 | } | |
1da177e4 LT |
2239 | kfree(conf->mirrors); |
2240 | conf->mirrors = newmirrors; | |
2241 | kfree(conf->poolinfo); | |
2242 | conf->poolinfo = newpoolinfo; | |
2243 | ||
c04be0aa | 2244 | spin_lock_irqsave(&conf->device_lock, flags); |
1da177e4 | 2245 | mddev->degraded += (raid_disks - conf->raid_disks); |
c04be0aa | 2246 | spin_unlock_irqrestore(&conf->device_lock, flags); |
1da177e4 | 2247 | conf->raid_disks = mddev->raid_disks = raid_disks; |
63c70c4f | 2248 | mddev->delta_disks = 0; |
1da177e4 | 2249 | |
6ea9c07c | 2250 | conf->last_used = 0; /* just make sure it is in-range */ |
17999be4 | 2251 | lower_barrier(conf); |
1da177e4 LT |
2252 | |
2253 | set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); | |
2254 | md_wakeup_thread(mddev->thread); | |
2255 | ||
2256 | mempool_destroy(oldpool); | |
2257 | return 0; | |
2258 | } | |
2259 | ||
500af87a | 2260 | static void raid1_quiesce(mddev_t *mddev, int state) |
36fa3063 | 2261 | { |
070ec55d | 2262 | conf_t *conf = mddev->private; |
36fa3063 N |
2263 | |
2264 | switch(state) { | |
6eef4b21 N |
2265 | case 2: /* wake for suspend */ |
2266 | wake_up(&conf->wait_barrier); | |
2267 | break; | |
9e6603da | 2268 | case 1: |
17999be4 | 2269 | raise_barrier(conf); |
36fa3063 | 2270 | break; |
9e6603da | 2271 | case 0: |
17999be4 | 2272 | lower_barrier(conf); |
36fa3063 N |
2273 | break; |
2274 | } | |
36fa3063 N |
2275 | } |
2276 | ||
709ae487 N |
2277 | static void *raid1_takeover(mddev_t *mddev) |
2278 | { | |
2279 | /* raid1 can take over: | |
2280 | * raid5 with 2 devices, any layout or chunk size | |
2281 | */ | |
2282 | if (mddev->level == 5 && mddev->raid_disks == 2) { | |
2283 | conf_t *conf; | |
2284 | mddev->new_level = 1; | |
2285 | mddev->new_layout = 0; | |
2286 | mddev->new_chunk_sectors = 0; | |
2287 | conf = setup_conf(mddev); | |
2288 | if (!IS_ERR(conf)) | |
2289 | conf->barrier = 1; | |
2290 | return conf; | |
2291 | } | |
2292 | return ERR_PTR(-EINVAL); | |
2293 | } | |
1da177e4 | 2294 | |
2604b703 | 2295 | static struct mdk_personality raid1_personality = |
1da177e4 LT |
2296 | { |
2297 | .name = "raid1", | |
2604b703 | 2298 | .level = 1, |
1da177e4 LT |
2299 | .owner = THIS_MODULE, |
2300 | .make_request = make_request, | |
2301 | .run = run, | |
2302 | .stop = stop, | |
2303 | .status = status, | |
2304 | .error_handler = error, | |
2305 | .hot_add_disk = raid1_add_disk, | |
2306 | .hot_remove_disk= raid1_remove_disk, | |
2307 | .spare_active = raid1_spare_active, | |
2308 | .sync_request = sync_request, | |
2309 | .resize = raid1_resize, | |
80c3a6ce | 2310 | .size = raid1_size, |
63c70c4f | 2311 | .check_reshape = raid1_reshape, |
36fa3063 | 2312 | .quiesce = raid1_quiesce, |
709ae487 | 2313 | .takeover = raid1_takeover, |
1da177e4 LT |
2314 | }; |
2315 | ||
2316 | static int __init raid_init(void) | |
2317 | { | |
2604b703 | 2318 | return register_md_personality(&raid1_personality); |
1da177e4 LT |
2319 | } |
2320 | ||
2321 | static void raid_exit(void) | |
2322 | { | |
2604b703 | 2323 | unregister_md_personality(&raid1_personality); |
1da177e4 LT |
2324 | } |
2325 | ||
2326 | module_init(raid_init); | |
2327 | module_exit(raid_exit); | |
2328 | MODULE_LICENSE("GPL"); | |
0efb9e61 | 2329 | MODULE_DESCRIPTION("RAID1 (mirroring) personality for MD"); |
1da177e4 | 2330 | MODULE_ALIAS("md-personality-3"); /* RAID1 */ |
d9d166c2 | 2331 | MODULE_ALIAS("md-raid1"); |
2604b703 | 2332 | MODULE_ALIAS("md-level-1"); |