Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | md_k.h : kernel internal structure of the Linux MD driver | |
3 | Copyright (C) 1996-98 Ingo Molnar, Gadi Oxman | |
4 | ||
5 | This program is free software; you can redistribute it and/or modify | |
6 | it under the terms of the GNU General Public License as published by | |
7 | the Free Software Foundation; either version 2, or (at your option) | |
8 | any later version. | |
9 | ||
10 | You should have received a copy of the GNU General Public License | |
11 | (for example /usr/src/linux/COPYING); if not, write to the Free | |
12 | Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | |
13 | */ | |
14 | ||
63fe0817 CH |
15 | #ifndef _MD_MD_H |
16 | #define _MD_MD_H | |
17 | ||
18 | #include <linux/blkdev.h> | |
19 | #include <linux/kobject.h> | |
20 | #include <linux/list.h> | |
21 | #include <linux/mm.h> | |
22 | #include <linux/mutex.h> | |
23 | #include <linux/timer.h> | |
24 | #include <linux/wait.h> | |
25 | #include <linux/workqueue.h> | |
9361401e | 26 | |
1da177e4 | 27 | #define MaxSector (~(sector_t)0) |
1da177e4 | 28 | |
1da177e4 LT |
29 | typedef struct mddev_s mddev_t; |
30 | typedef struct mdk_rdev_s mdk_rdev_t; | |
31 | ||
1da177e4 LT |
32 | /* |
33 | * options passed in raidrun: | |
34 | */ | |
35 | ||
e8703fe1 | 36 | /* Currently this must fit in an 'int' */ |
8932c2e0 | 37 | #define MAX_CHUNK_SIZE (1<<30) |
1da177e4 | 38 | |
1da177e4 LT |
39 | /* |
40 | * MD's 'extended' device | |
41 | */ | |
42 | struct mdk_rdev_s | |
43 | { | |
44 | struct list_head same_set; /* RAID devices within the same set */ | |
45 | ||
dd8ac336 | 46 | sector_t sectors; /* Device size (in 512bytes sectors) */ |
1da177e4 | 47 | mddev_t *mddev; /* RAID array if running */ |
eea1bf38 | 48 | int last_events; /* IO event timestamp */ |
1da177e4 LT |
49 | |
50 | struct block_device *bdev; /* block device handle */ | |
51 | ||
52 | struct page *sb_page; | |
53 | int sb_loaded; | |
42543769 | 54 | __u64 sb_events; |
1da177e4 | 55 | sector_t data_offset; /* start of data in array */ |
0f420358 | 56 | sector_t sb_start; /* offset of the super block (in 512byte sectors) */ |
0002b271 | 57 | int sb_size; /* bytes in the superblock */ |
1da177e4 LT |
58 | int preferred_minor; /* autorun support */ |
59 | ||
86e6ffdd N |
60 | struct kobject kobj; |
61 | ||
1da177e4 LT |
62 | /* A device can be in one of three states based on two flags: |
63 | * Not working: faulty==1 in_sync==0 | |
64 | * Fully working: faulty==0 in_sync==1 | |
65 | * Working, but not | |
66 | * in sync with array | |
67 | * faulty==0 in_sync==0 | |
68 | * | |
69 | * It can never have faulty==1, in_sync==1 | |
70 | * This reduces the burden of testing multiple flags in many cases | |
71 | */ | |
1da177e4 | 72 | |
b2d444d7 N |
73 | unsigned long flags; |
74 | #define Faulty 1 /* device is known to have a fault */ | |
75 | #define In_sync 2 /* device is in_sync with rest of array */ | |
8ddf9efe | 76 | #define WriteMostly 4 /* Avoid reading if at all possible */ |
a9701a30 | 77 | #define BarriersNotsupp 5 /* BIO_RW_BARRIER is not supported */ |
c5d79adb N |
78 | #define AllReserved 6 /* If whole device is reserved for |
79 | * one array */ | |
d0fae18f | 80 | #define AutoDetected 7 /* added by auto-detect */ |
6bfe0b49 DW |
81 | #define Blocked 8 /* An error occured on an externally |
82 | * managed array, don't allow writes | |
83 | * until it is cleared */ | |
52664732 NB |
84 | #define StateChanged 9 /* Faulty or Blocked has changed during |
85 | * interrupt, so it needs to be | |
86 | * notified by the thread */ | |
6bfe0b49 | 87 | wait_queue_head_t blocked_wait; |
8ddf9efe | 88 | |
1da177e4 LT |
89 | int desc_nr; /* descriptor index in the superblock */ |
90 | int raid_disk; /* role of device in array */ | |
41158c7e N |
91 | int saved_raid_disk; /* role that device used to have in the |
92 | * array and could again if we did a partial | |
93 | * resync from the bitmap | |
94 | */ | |
5fd6c1dc N |
95 | sector_t recovery_offset;/* If this device has been partially |
96 | * recovered, this is where we were | |
97 | * up to. | |
98 | */ | |
1da177e4 LT |
99 | |
100 | atomic_t nr_pending; /* number of pending requests. | |
101 | * only maintained for arrays that | |
102 | * support hot removal | |
103 | */ | |
ba22dcbf N |
104 | atomic_t read_errors; /* number of consecutive read errors that |
105 | * we have tried to ignore. | |
106 | */ | |
4dbcdc75 N |
107 | atomic_t corrected_errors; /* number of corrected read errors, |
108 | * for reporting to userspace and storing | |
109 | * in superblock. | |
110 | */ | |
5792a285 | 111 | struct work_struct del_work; /* used for delayed sysfs removal */ |
3c0ee63a N |
112 | |
113 | struct sysfs_dirent *sysfs_state; /* handle for 'state' | |
114 | * sysfs entry */ | |
1da177e4 LT |
115 | }; |
116 | ||
1da177e4 LT |
117 | struct mddev_s |
118 | { | |
119 | void *private; | |
2604b703 | 120 | struct mdk_personality *pers; |
1da177e4 LT |
121 | dev_t unit; |
122 | int md_minor; | |
123 | struct list_head disks; | |
850b2b42 N |
124 | unsigned long flags; |
125 | #define MD_CHANGE_DEVS 0 /* Some device status has changed */ | |
126 | #define MD_CHANGE_CLEAN 1 /* transition to or from 'clean' */ | |
127 | #define MD_CHANGE_PENDING 2 /* superblock update in progress */ | |
128 | ||
409c57f3 N |
129 | int suspended; |
130 | atomic_t active_io; | |
1da177e4 LT |
131 | int ro; |
132 | ||
133 | struct gendisk *gendisk; | |
134 | ||
eae1701f | 135 | struct kobject kobj; |
d3374825 N |
136 | int hold_active; |
137 | #define UNTIL_IOCTL 1 | |
efeb53c0 | 138 | #define UNTIL_STOP 2 |
eae1701f | 139 | |
1da177e4 LT |
140 | /* Superblock information */ |
141 | int major_version, | |
142 | minor_version, | |
143 | patch_version; | |
144 | int persistent; | |
e691063a N |
145 | int external; /* metadata is |
146 | * managed externally */ | |
147 | char metadata_type[17]; /* externally set*/ | |
1da177e4 LT |
148 | int chunk_size; |
149 | time_t ctime, utime; | |
150 | int level, layout; | |
d9d166c2 | 151 | char clevel[16]; |
1da177e4 LT |
152 | int raid_disks; |
153 | int max_disks; | |
58c0fed4 AN |
154 | sector_t dev_sectors; /* used size of |
155 | * component devices */ | |
f233ea5c | 156 | sector_t array_sectors; /* exported array size */ |
b522adcd DW |
157 | int external_size; /* size managed |
158 | * externally */ | |
1da177e4 LT |
159 | __u64 events; |
160 | ||
161 | char uuid[16]; | |
162 | ||
f6705578 N |
163 | /* If the array is being reshaped, we need to record the |
164 | * new shape and an indication of where we are up to. | |
165 | * This is written to the superblock. | |
166 | * If reshape_position is MaxSector, then no reshape is happening (yet). | |
167 | */ | |
168 | sector_t reshape_position; | |
169 | int delta_disks, new_level, new_layout, new_chunk; | |
170 | ||
1da177e4 LT |
171 | struct mdk_thread_s *thread; /* management thread */ |
172 | struct mdk_thread_s *sync_thread; /* doing resync or reconstruct */ | |
ff4e8d9a | 173 | sector_t curr_resync; /* last block scheduled */ |
97e4f42d N |
174 | /* As resync requests can complete out of order, we cannot easily track |
175 | * how much resync has been completed. So we occasionally pause until | |
176 | * everything completes, then set curr_resync_completed to curr_resync. | |
177 | * As such it may be well behind the real resync mark, but it is a value | |
178 | * we are certain of. | |
179 | */ | |
180 | sector_t curr_resync_completed; | |
1da177e4 LT |
181 | unsigned long resync_mark; /* a recent timestamp */ |
182 | sector_t resync_mark_cnt;/* blocks written at resync_mark */ | |
ff4e8d9a | 183 | sector_t curr_mark_cnt; /* blocks scheduled now */ |
1da177e4 LT |
184 | |
185 | sector_t resync_max_sectors; /* may be set by personality */ | |
9d88883e N |
186 | |
187 | sector_t resync_mismatches; /* count of sectors where | |
188 | * parity/replica mismatch found | |
189 | */ | |
e464eafd N |
190 | |
191 | /* allow user-space to request suspension of IO to regions of the array */ | |
192 | sector_t suspend_lo; | |
193 | sector_t suspend_hi; | |
88202a0c N |
194 | /* if zero, use the system-wide default */ |
195 | int sync_speed_min; | |
196 | int sync_speed_max; | |
197 | ||
90b08710 BS |
198 | /* resync even though the same disks are shared among md-devices */ |
199 | int parallel_resync; | |
200 | ||
6ff8d8ec | 201 | int ok_start_degraded; |
1da177e4 LT |
202 | /* recovery/resync flags |
203 | * NEEDED: we might need to start a resync/recover | |
204 | * RUNNING: a thread is running, or about to be started | |
205 | * SYNC: actually doing a resync, not a recovery | |
72a23c21 | 206 | * RECOVER: doing recovery, or need to try it. |
dfc70645 | 207 | * INTR: resync needs to be aborted for some reason |
1da177e4 | 208 | * DONE: thread is done and is waiting to be reaped |
24dd469d N |
209 | * REQUEST: user-space has requested a sync (used with SYNC) |
210 | * CHECK: user-space request for for check-only, no repair | |
ccfcc3c1 N |
211 | * RESHAPE: A reshape is happening |
212 | * | |
213 | * If neither SYNC or RESHAPE are set, then it is a recovery. | |
1da177e4 LT |
214 | */ |
215 | #define MD_RECOVERY_RUNNING 0 | |
216 | #define MD_RECOVERY_SYNC 1 | |
72a23c21 | 217 | #define MD_RECOVERY_RECOVER 2 |
1da177e4 LT |
218 | #define MD_RECOVERY_INTR 3 |
219 | #define MD_RECOVERY_DONE 4 | |
220 | #define MD_RECOVERY_NEEDED 5 | |
24dd469d N |
221 | #define MD_RECOVERY_REQUESTED 6 |
222 | #define MD_RECOVERY_CHECK 7 | |
ccfcc3c1 | 223 | #define MD_RECOVERY_RESHAPE 8 |
5fd6c1dc N |
224 | #define MD_RECOVERY_FROZEN 9 |
225 | ||
1da177e4 | 226 | unsigned long recovery; |
4044ba58 N |
227 | int recovery_disabled; /* if we detect that recovery |
228 | * will always fail, set this | |
229 | * so we don't loop trying */ | |
1da177e4 LT |
230 | |
231 | int in_sync; /* know to not need resync */ | |
df5b89b3 | 232 | struct mutex reconfig_mutex; |
f2ea68cf N |
233 | atomic_t active; /* general refcount */ |
234 | atomic_t openers; /* number of active opens */ | |
1da177e4 | 235 | |
44ce6294 | 236 | int changed; /* true if we might need to reread partition info */ |
1da177e4 LT |
237 | int degraded; /* whether md should consider |
238 | * adding a spare | |
239 | */ | |
a9701a30 N |
240 | int barriers_work; /* initialised to true, cleared as soon |
241 | * as a barrier request to slave | |
242 | * fails. Only supported | |
243 | */ | |
244 | struct bio *biolist; /* bios that need to be retried | |
245 | * because BIO_RW_BARRIER is not supported | |
246 | */ | |
1da177e4 LT |
247 | |
248 | atomic_t recovery_active; /* blocks scheduled, but not written */ | |
249 | wait_queue_head_t recovery_wait; | |
250 | sector_t recovery_cp; | |
5e96ee65 NB |
251 | sector_t resync_min; /* user requested sync |
252 | * starts here */ | |
c6207277 N |
253 | sector_t resync_max; /* resync should pause |
254 | * when it gets here */ | |
06d91a5f | 255 | |
b62b7590 N |
256 | struct sysfs_dirent *sysfs_state; /* handle for 'array_state' |
257 | * file in sysfs. | |
258 | */ | |
0c3573f1 | 259 | struct sysfs_dirent *sysfs_action; /* handle for 'sync_action' */ |
b62b7590 | 260 | |
d3374825 N |
261 | struct work_struct del_work; /* used for delayed sysfs removal */ |
262 | ||
06d91a5f | 263 | spinlock_t write_lock; |
3d310eb7 | 264 | wait_queue_head_t sb_wait; /* for waiting on superblock updates */ |
7bfa19f2 | 265 | atomic_t pending_writes; /* number of active superblock writes */ |
06d91a5f | 266 | |
1da177e4 LT |
267 | unsigned int safemode; /* if set, update "clean" superblock |
268 | * when no writes pending. | |
269 | */ | |
270 | unsigned int safemode_delay; | |
271 | struct timer_list safemode_timer; | |
272 | atomic_t writes_pending; | |
165125e1 | 273 | struct request_queue *queue; /* for plugging ... */ |
1da177e4 | 274 | |
4b6d287f N |
275 | atomic_t write_behind; /* outstanding async IO */ |
276 | unsigned int max_write_behind; /* 0 = sync */ | |
277 | ||
32a7627c N |
278 | struct bitmap *bitmap; /* the bitmap for the device */ |
279 | struct file *bitmap_file; /* the bitmap file */ | |
a654b9d8 N |
280 | long bitmap_offset; /* offset from superblock of |
281 | * start of bitmap. May be | |
282 | * negative, but not '0' | |
283 | */ | |
36fa3063 N |
284 | long default_bitmap_offset; /* this is the offset to use when |
285 | * hot-adding a bitmap. It should | |
286 | * eventually be settable by sysfs. | |
287 | */ | |
32a7627c | 288 | |
1da177e4 LT |
289 | struct list_head all_mddevs; |
290 | }; | |
291 | ||
292 | ||
293 | static inline void rdev_dec_pending(mdk_rdev_t *rdev, mddev_t *mddev) | |
294 | { | |
b2d444d7 | 295 | int faulty = test_bit(Faulty, &rdev->flags); |
1da177e4 LT |
296 | if (atomic_dec_and_test(&rdev->nr_pending) && faulty) |
297 | set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); | |
298 | } | |
299 | ||
300 | static inline void md_sync_acct(struct block_device *bdev, unsigned long nr_sectors) | |
301 | { | |
302 | atomic_add(nr_sectors, &bdev->bd_contains->bd_disk->sync_io); | |
303 | } | |
304 | ||
2604b703 | 305 | struct mdk_personality |
1da177e4 LT |
306 | { |
307 | char *name; | |
2604b703 N |
308 | int level; |
309 | struct list_head list; | |
1da177e4 | 310 | struct module *owner; |
165125e1 | 311 | int (*make_request)(struct request_queue *q, struct bio *bio); |
1da177e4 LT |
312 | int (*run)(mddev_t *mddev); |
313 | int (*stop)(mddev_t *mddev); | |
314 | void (*status)(struct seq_file *seq, mddev_t *mddev); | |
315 | /* error_handler must set ->faulty and clear ->in_sync | |
316 | * if appropriate, and should abort recovery if needed | |
317 | */ | |
318 | void (*error_handler)(mddev_t *mddev, mdk_rdev_t *rdev); | |
319 | int (*hot_add_disk) (mddev_t *mddev, mdk_rdev_t *rdev); | |
320 | int (*hot_remove_disk) (mddev_t *mddev, int number); | |
321 | int (*spare_active) (mddev_t *mddev); | |
57afd89f | 322 | sector_t (*sync_request)(mddev_t *mddev, sector_t sector_nr, int *skipped, int go_faster); |
1da177e4 | 323 | int (*resize) (mddev_t *mddev, sector_t sectors); |
80c3a6ce | 324 | sector_t (*size) (mddev_t *mddev, sector_t sectors, int raid_disks); |
63c70c4f N |
325 | int (*check_reshape) (mddev_t *mddev); |
326 | int (*start_reshape) (mddev_t *mddev); | |
cea9c228 | 327 | void (*finish_reshape) (mddev_t *mddev); |
1da177e4 | 328 | int (*reconfig) (mddev_t *mddev, int layout, int chunk_size); |
36fa3063 N |
329 | /* quiesce moves between quiescence states |
330 | * 0 - fully active | |
331 | * 1 - no new requests allowed | |
332 | * others - reserved | |
333 | */ | |
334 | void (*quiesce) (mddev_t *mddev, int state); | |
245f46c2 N |
335 | /* takeover is used to transition an array from one |
336 | * personality to another. The new personality must be able | |
337 | * to handle the data in the current layout. | |
338 | * e.g. 2drive raid1 -> 2drive raid5 | |
339 | * ndrive raid5 -> degraded n+1drive raid6 with special layout | |
340 | * If the takeover succeeds, a new 'private' structure is returned. | |
341 | * This needs to be installed and then ->run used to activate the | |
342 | * array. | |
343 | */ | |
344 | void *(*takeover) (mddev_t *mddev); | |
1da177e4 LT |
345 | }; |
346 | ||
347 | ||
007583c9 N |
348 | struct md_sysfs_entry { |
349 | struct attribute attr; | |
350 | ssize_t (*show)(mddev_t *, char *); | |
351 | ssize_t (*store)(mddev_t *, const char *, size_t); | |
352 | }; | |
353 | ||
354 | ||
1da177e4 LT |
355 | static inline char * mdname (mddev_t * mddev) |
356 | { | |
357 | return mddev->gendisk ? mddev->gendisk->disk_name : "mdX"; | |
358 | } | |
359 | ||
1da177e4 LT |
360 | /* |
361 | * iterates through some rdev ringlist. It's safe to remove the | |
362 | * current 'rdev'. Dont touch 'tmp' though. | |
363 | */ | |
159ec1fc CR |
364 | #define rdev_for_each_list(rdev, tmp, head) \ |
365 | list_for_each_entry_safe(rdev, tmp, head, same_set) | |
366 | ||
1da177e4 LT |
367 | /* |
368 | * iterates through the 'same array disks' ringlist | |
369 | */ | |
d089c6af | 370 | #define rdev_for_each(rdev, tmp, mddev) \ |
159ec1fc | 371 | list_for_each_entry_safe(rdev, tmp, &((mddev)->disks), same_set) |
1da177e4 | 372 | |
4b80991c N |
373 | #define rdev_for_each_rcu(rdev, mddev) \ |
374 | list_for_each_entry_rcu(rdev, &((mddev)->disks), same_set) | |
375 | ||
1da177e4 LT |
376 | typedef struct mdk_thread_s { |
377 | void (*run) (mddev_t *mddev); | |
378 | mddev_t *mddev; | |
379 | wait_queue_head_t wqueue; | |
380 | unsigned long flags; | |
1da177e4 | 381 | struct task_struct *tsk; |
32a7627c | 382 | unsigned long timeout; |
1da177e4 LT |
383 | } mdk_thread_t; |
384 | ||
385 | #define THREAD_WAKEUP 0 | |
386 | ||
387 | #define __wait_event_lock_irq(wq, condition, lock, cmd) \ | |
388 | do { \ | |
389 | wait_queue_t __wait; \ | |
390 | init_waitqueue_entry(&__wait, current); \ | |
391 | \ | |
392 | add_wait_queue(&wq, &__wait); \ | |
393 | for (;;) { \ | |
394 | set_current_state(TASK_UNINTERRUPTIBLE); \ | |
395 | if (condition) \ | |
396 | break; \ | |
397 | spin_unlock_irq(&lock); \ | |
398 | cmd; \ | |
399 | schedule(); \ | |
400 | spin_lock_irq(&lock); \ | |
401 | } \ | |
402 | current->state = TASK_RUNNING; \ | |
403 | remove_wait_queue(&wq, &__wait); \ | |
404 | } while (0) | |
405 | ||
406 | #define wait_event_lock_irq(wq, condition, lock, cmd) \ | |
407 | do { \ | |
408 | if (condition) \ | |
409 | break; \ | |
410 | __wait_event_lock_irq(wq, condition, lock, cmd); \ | |
411 | } while (0) | |
412 | ||
1345b1d8 N |
413 | static inline void safe_put_page(struct page *p) |
414 | { | |
415 | if (p) put_page(p); | |
416 | } | |
417 | ||
92022950 N |
418 | extern int register_md_personality(struct mdk_personality *p); |
419 | extern int unregister_md_personality(struct mdk_personality *p); | |
420 | extern mdk_thread_t * md_register_thread(void (*run) (mddev_t *mddev), | |
421 | mddev_t *mddev, const char *name); | |
422 | extern void md_unregister_thread(mdk_thread_t *thread); | |
423 | extern void md_wakeup_thread(mdk_thread_t *thread); | |
424 | extern void md_check_recovery(mddev_t *mddev); | |
425 | extern void md_write_start(mddev_t *mddev, struct bio *bi); | |
426 | extern void md_write_end(mddev_t *mddev); | |
427 | extern void md_done_sync(mddev_t *mddev, int blocks, int ok); | |
428 | extern void md_error(mddev_t *mddev, mdk_rdev_t *rdev); | |
429 | ||
430 | extern void md_super_write(mddev_t *mddev, mdk_rdev_t *rdev, | |
431 | sector_t sector, int size, struct page *page); | |
432 | extern void md_super_wait(mddev_t *mddev); | |
433 | extern int sync_page_io(struct block_device *bdev, sector_t sector, int size, | |
434 | struct page *page, int rw); | |
435 | extern void md_do_sync(mddev_t *mddev); | |
436 | extern void md_new_event(mddev_t *mddev); | |
437 | extern int md_allow_write(mddev_t *mddev); | |
438 | extern void md_wait_for_blocked_rdev(mdk_rdev_t *rdev, mddev_t *mddev); | |
1f403624 | 439 | extern void md_set_array_sectors(mddev_t *mddev, sector_t array_sectors); |
63fe0817 CH |
440 | |
441 | #endif /* _MD_MD_H */ |