diff options
author | NeilBrown <neilb@suse.de> | 2009-03-30 23:33:13 -0400 |
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committer | NeilBrown <neilb@suse.de> | 2009-03-30 23:33:13 -0400 |
commit | 43b2e5d86d8bdd77386226db0bc961529492c043 (patch) | |
tree | 601a885b1410324678cf319eee77cc54a02f2cf3 /drivers/md/md.h | |
parent | bff61975b3d6c18ee31457cc5b4d73042f44915f (diff) |
md: move md_k.h from include/linux/raid/ to drivers/md/
It really is nicer to keep related code together..
Signed-off-by: NeilBrown <neilb@suse.de>
Diffstat (limited to 'drivers/md/md.h')
-rw-r--r-- | drivers/md/md.h | 411 |
1 files changed, 411 insertions, 0 deletions
diff --git a/drivers/md/md.h b/drivers/md/md.h new file mode 100644 index 000000000000..e78b3c1d55fd --- /dev/null +++ b/drivers/md/md.h | |||
@@ -0,0 +1,411 @@ | |||
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 | |||
15 | #ifndef _MD_K_H | ||
16 | #define _MD_K_H | ||
17 | |||
18 | #ifdef CONFIG_BLOCK | ||
19 | |||
20 | #define MaxSector (~(sector_t)0) | ||
21 | |||
22 | typedef struct mddev_s mddev_t; | ||
23 | typedef struct mdk_rdev_s mdk_rdev_t; | ||
24 | |||
25 | /* | ||
26 | * options passed in raidrun: | ||
27 | */ | ||
28 | |||
29 | /* Currently this must fit in an 'int' */ | ||
30 | #define MAX_CHUNK_SIZE (1<<30) | ||
31 | |||
32 | /* | ||
33 | * MD's 'extended' device | ||
34 | */ | ||
35 | struct mdk_rdev_s | ||
36 | { | ||
37 | struct list_head same_set; /* RAID devices within the same set */ | ||
38 | |||
39 | sector_t size; /* Device size (in blocks) */ | ||
40 | mddev_t *mddev; /* RAID array if running */ | ||
41 | int last_events; /* IO event timestamp */ | ||
42 | |||
43 | struct block_device *bdev; /* block device handle */ | ||
44 | |||
45 | struct page *sb_page; | ||
46 | int sb_loaded; | ||
47 | __u64 sb_events; | ||
48 | sector_t data_offset; /* start of data in array */ | ||
49 | sector_t sb_start; /* offset of the super block (in 512byte sectors) */ | ||
50 | int sb_size; /* bytes in the superblock */ | ||
51 | int preferred_minor; /* autorun support */ | ||
52 | |||
53 | struct kobject kobj; | ||
54 | |||
55 | /* A device can be in one of three states based on two flags: | ||
56 | * Not working: faulty==1 in_sync==0 | ||
57 | * Fully working: faulty==0 in_sync==1 | ||
58 | * Working, but not | ||
59 | * in sync with array | ||
60 | * faulty==0 in_sync==0 | ||
61 | * | ||
62 | * It can never have faulty==1, in_sync==1 | ||
63 | * This reduces the burden of testing multiple flags in many cases | ||
64 | */ | ||
65 | |||
66 | unsigned long flags; | ||
67 | #define Faulty 1 /* device is known to have a fault */ | ||
68 | #define In_sync 2 /* device is in_sync with rest of array */ | ||
69 | #define WriteMostly 4 /* Avoid reading if at all possible */ | ||
70 | #define BarriersNotsupp 5 /* BIO_RW_BARRIER is not supported */ | ||
71 | #define AllReserved 6 /* If whole device is reserved for | ||
72 | * one array */ | ||
73 | #define AutoDetected 7 /* added by auto-detect */ | ||
74 | #define Blocked 8 /* An error occured on an externally | ||
75 | * managed array, don't allow writes | ||
76 | * until it is cleared */ | ||
77 | #define StateChanged 9 /* Faulty or Blocked has changed during | ||
78 | * interrupt, so it needs to be | ||
79 | * notified by the thread */ | ||
80 | wait_queue_head_t blocked_wait; | ||
81 | |||
82 | int desc_nr; /* descriptor index in the superblock */ | ||
83 | int raid_disk; /* role of device in array */ | ||
84 | int saved_raid_disk; /* role that device used to have in the | ||
85 | * array and could again if we did a partial | ||
86 | * resync from the bitmap | ||
87 | */ | ||
88 | sector_t recovery_offset;/* If this device has been partially | ||
89 | * recovered, this is where we were | ||
90 | * up to. | ||
91 | */ | ||
92 | |||
93 | atomic_t nr_pending; /* number of pending requests. | ||
94 | * only maintained for arrays that | ||
95 | * support hot removal | ||
96 | */ | ||
97 | atomic_t read_errors; /* number of consecutive read errors that | ||
98 | * we have tried to ignore. | ||
99 | */ | ||
100 | atomic_t corrected_errors; /* number of corrected read errors, | ||
101 | * for reporting to userspace and storing | ||
102 | * in superblock. | ||
103 | */ | ||
104 | struct work_struct del_work; /* used for delayed sysfs removal */ | ||
105 | |||
106 | struct sysfs_dirent *sysfs_state; /* handle for 'state' | ||
107 | * sysfs entry */ | ||
108 | }; | ||
109 | |||
110 | struct mddev_s | ||
111 | { | ||
112 | void *private; | ||
113 | struct mdk_personality *pers; | ||
114 | dev_t unit; | ||
115 | int md_minor; | ||
116 | struct list_head disks; | ||
117 | unsigned long flags; | ||
118 | #define MD_CHANGE_DEVS 0 /* Some device status has changed */ | ||
119 | #define MD_CHANGE_CLEAN 1 /* transition to or from 'clean' */ | ||
120 | #define MD_CHANGE_PENDING 2 /* superblock update in progress */ | ||
121 | |||
122 | int ro; | ||
123 | |||
124 | struct gendisk *gendisk; | ||
125 | |||
126 | struct kobject kobj; | ||
127 | int hold_active; | ||
128 | #define UNTIL_IOCTL 1 | ||
129 | #define UNTIL_STOP 2 | ||
130 | |||
131 | /* Superblock information */ | ||
132 | int major_version, | ||
133 | minor_version, | ||
134 | patch_version; | ||
135 | int persistent; | ||
136 | int external; /* metadata is | ||
137 | * managed externally */ | ||
138 | char metadata_type[17]; /* externally set*/ | ||
139 | int chunk_size; | ||
140 | time_t ctime, utime; | ||
141 | int level, layout; | ||
142 | char clevel[16]; | ||
143 | int raid_disks; | ||
144 | int max_disks; | ||
145 | sector_t size; /* used size of component devices */ | ||
146 | sector_t array_sectors; /* exported array size */ | ||
147 | __u64 events; | ||
148 | |||
149 | char uuid[16]; | ||
150 | |||
151 | /* If the array is being reshaped, we need to record the | ||
152 | * new shape and an indication of where we are up to. | ||
153 | * This is written to the superblock. | ||
154 | * If reshape_position is MaxSector, then no reshape is happening (yet). | ||
155 | */ | ||
156 | sector_t reshape_position; | ||
157 | int delta_disks, new_level, new_layout, new_chunk; | ||
158 | |||
159 | struct mdk_thread_s *thread; /* management thread */ | ||
160 | struct mdk_thread_s *sync_thread; /* doing resync or reconstruct */ | ||
161 | sector_t curr_resync; /* last block scheduled */ | ||
162 | unsigned long resync_mark; /* a recent timestamp */ | ||
163 | sector_t resync_mark_cnt;/* blocks written at resync_mark */ | ||
164 | sector_t curr_mark_cnt; /* blocks scheduled now */ | ||
165 | |||
166 | sector_t resync_max_sectors; /* may be set by personality */ | ||
167 | |||
168 | sector_t resync_mismatches; /* count of sectors where | ||
169 | * parity/replica mismatch found | ||
170 | */ | ||
171 | |||
172 | /* allow user-space to request suspension of IO to regions of the array */ | ||
173 | sector_t suspend_lo; | ||
174 | sector_t suspend_hi; | ||
175 | /* if zero, use the system-wide default */ | ||
176 | int sync_speed_min; | ||
177 | int sync_speed_max; | ||
178 | |||
179 | /* resync even though the same disks are shared among md-devices */ | ||
180 | int parallel_resync; | ||
181 | |||
182 | int ok_start_degraded; | ||
183 | /* recovery/resync flags | ||
184 | * NEEDED: we might need to start a resync/recover | ||
185 | * RUNNING: a thread is running, or about to be started | ||
186 | * SYNC: actually doing a resync, not a recovery | ||
187 | * RECOVER: doing recovery, or need to try it. | ||
188 | * INTR: resync needs to be aborted for some reason | ||
189 | * DONE: thread is done and is waiting to be reaped | ||
190 | * REQUEST: user-space has requested a sync (used with SYNC) | ||
191 | * CHECK: user-space request for for check-only, no repair | ||
192 | * RESHAPE: A reshape is happening | ||
193 | * | ||
194 | * If neither SYNC or RESHAPE are set, then it is a recovery. | ||
195 | */ | ||
196 | #define MD_RECOVERY_RUNNING 0 | ||
197 | #define MD_RECOVERY_SYNC 1 | ||
198 | #define MD_RECOVERY_RECOVER 2 | ||
199 | #define MD_RECOVERY_INTR 3 | ||
200 | #define MD_RECOVERY_DONE 4 | ||
201 | #define MD_RECOVERY_NEEDED 5 | ||
202 | #define MD_RECOVERY_REQUESTED 6 | ||
203 | #define MD_RECOVERY_CHECK 7 | ||
204 | #define MD_RECOVERY_RESHAPE 8 | ||
205 | #define MD_RECOVERY_FROZEN 9 | ||
206 | |||
207 | unsigned long recovery; | ||
208 | int recovery_disabled; /* if we detect that recovery | ||
209 | * will always fail, set this | ||
210 | * so we don't loop trying */ | ||
211 | |||
212 | int in_sync; /* know to not need resync */ | ||
213 | struct mutex reconfig_mutex; | ||
214 | atomic_t active; /* general refcount */ | ||
215 | atomic_t openers; /* number of active opens */ | ||
216 | |||
217 | int changed; /* true if we might need to reread partition info */ | ||
218 | int degraded; /* whether md should consider | ||
219 | * adding a spare | ||
220 | */ | ||
221 | int barriers_work; /* initialised to true, cleared as soon | ||
222 | * as a barrier request to slave | ||
223 | * fails. Only supported | ||
224 | */ | ||
225 | struct bio *biolist; /* bios that need to be retried | ||
226 | * because BIO_RW_BARRIER is not supported | ||
227 | */ | ||
228 | |||
229 | atomic_t recovery_active; /* blocks scheduled, but not written */ | ||
230 | wait_queue_head_t recovery_wait; | ||
231 | sector_t recovery_cp; | ||
232 | sector_t resync_min; /* user requested sync | ||
233 | * starts here */ | ||
234 | sector_t resync_max; /* resync should pause | ||
235 | * when it gets here */ | ||
236 | |||
237 | struct sysfs_dirent *sysfs_state; /* handle for 'array_state' | ||
238 | * file in sysfs. | ||
239 | */ | ||
240 | struct sysfs_dirent *sysfs_action; /* handle for 'sync_action' */ | ||
241 | |||
242 | struct work_struct del_work; /* used for delayed sysfs removal */ | ||
243 | |||
244 | spinlock_t write_lock; | ||
245 | wait_queue_head_t sb_wait; /* for waiting on superblock updates */ | ||
246 | atomic_t pending_writes; /* number of active superblock writes */ | ||
247 | |||
248 | unsigned int safemode; /* if set, update "clean" superblock | ||
249 | * when no writes pending. | ||
250 | */ | ||
251 | unsigned int safemode_delay; | ||
252 | struct timer_list safemode_timer; | ||
253 | atomic_t writes_pending; | ||
254 | struct request_queue *queue; /* for plugging ... */ | ||
255 | |||
256 | atomic_t write_behind; /* outstanding async IO */ | ||
257 | unsigned int max_write_behind; /* 0 = sync */ | ||
258 | |||
259 | struct bitmap *bitmap; /* the bitmap for the device */ | ||
260 | struct file *bitmap_file; /* the bitmap file */ | ||
261 | long bitmap_offset; /* offset from superblock of | ||
262 | * start of bitmap. May be | ||
263 | * negative, but not '0' | ||
264 | */ | ||
265 | long default_bitmap_offset; /* this is the offset to use when | ||
266 | * hot-adding a bitmap. It should | ||
267 | * eventually be settable by sysfs. | ||
268 | */ | ||
269 | |||
270 | struct list_head all_mddevs; | ||
271 | }; | ||
272 | |||
273 | |||
274 | static inline void rdev_dec_pending(mdk_rdev_t *rdev, mddev_t *mddev) | ||
275 | { | ||
276 | int faulty = test_bit(Faulty, &rdev->flags); | ||
277 | if (atomic_dec_and_test(&rdev->nr_pending) && faulty) | ||
278 | set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); | ||
279 | } | ||
280 | |||
281 | static inline void md_sync_acct(struct block_device *bdev, unsigned long nr_sectors) | ||
282 | { | ||
283 | atomic_add(nr_sectors, &bdev->bd_contains->bd_disk->sync_io); | ||
284 | } | ||
285 | |||
286 | struct mdk_personality | ||
287 | { | ||
288 | char *name; | ||
289 | int level; | ||
290 | struct list_head list; | ||
291 | struct module *owner; | ||
292 | int (*make_request)(struct request_queue *q, struct bio *bio); | ||
293 | int (*run)(mddev_t *mddev); | ||
294 | int (*stop)(mddev_t *mddev); | ||
295 | void (*status)(struct seq_file *seq, mddev_t *mddev); | ||
296 | /* error_handler must set ->faulty and clear ->in_sync | ||
297 | * if appropriate, and should abort recovery if needed | ||
298 | */ | ||
299 | void (*error_handler)(mddev_t *mddev, mdk_rdev_t *rdev); | ||
300 | int (*hot_add_disk) (mddev_t *mddev, mdk_rdev_t *rdev); | ||
301 | int (*hot_remove_disk) (mddev_t *mddev, int number); | ||
302 | int (*spare_active) (mddev_t *mddev); | ||
303 | sector_t (*sync_request)(mddev_t *mddev, sector_t sector_nr, int *skipped, int go_faster); | ||
304 | int (*resize) (mddev_t *mddev, sector_t sectors); | ||
305 | int (*check_reshape) (mddev_t *mddev); | ||
306 | int (*start_reshape) (mddev_t *mddev); | ||
307 | int (*reconfig) (mddev_t *mddev, int layout, int chunk_size); | ||
308 | /* quiesce moves between quiescence states | ||
309 | * 0 - fully active | ||
310 | * 1 - no new requests allowed | ||
311 | * others - reserved | ||
312 | */ | ||
313 | void (*quiesce) (mddev_t *mddev, int state); | ||
314 | }; | ||
315 | |||
316 | |||
317 | struct md_sysfs_entry { | ||
318 | struct attribute attr; | ||
319 | ssize_t (*show)(mddev_t *, char *); | ||
320 | ssize_t (*store)(mddev_t *, const char *, size_t); | ||
321 | }; | ||
322 | |||
323 | |||
324 | static inline char * mdname (mddev_t * mddev) | ||
325 | { | ||
326 | return mddev->gendisk ? mddev->gendisk->disk_name : "mdX"; | ||
327 | } | ||
328 | |||
329 | /* | ||
330 | * iterates through some rdev ringlist. It's safe to remove the | ||
331 | * current 'rdev'. Dont touch 'tmp' though. | ||
332 | */ | ||
333 | #define rdev_for_each_list(rdev, tmp, head) \ | ||
334 | list_for_each_entry_safe(rdev, tmp, head, same_set) | ||
335 | |||
336 | /* | ||
337 | * iterates through the 'same array disks' ringlist | ||
338 | */ | ||
339 | #define rdev_for_each(rdev, tmp, mddev) \ | ||
340 | list_for_each_entry_safe(rdev, tmp, &((mddev)->disks), same_set) | ||
341 | |||
342 | #define rdev_for_each_rcu(rdev, mddev) \ | ||
343 | list_for_each_entry_rcu(rdev, &((mddev)->disks), same_set) | ||
344 | |||
345 | typedef struct mdk_thread_s { | ||
346 | void (*run) (mddev_t *mddev); | ||
347 | mddev_t *mddev; | ||
348 | wait_queue_head_t wqueue; | ||
349 | unsigned long flags; | ||
350 | struct task_struct *tsk; | ||
351 | unsigned long timeout; | ||
352 | } mdk_thread_t; | ||
353 | |||
354 | #define THREAD_WAKEUP 0 | ||
355 | |||
356 | #define __wait_event_lock_irq(wq, condition, lock, cmd) \ | ||
357 | do { \ | ||
358 | wait_queue_t __wait; \ | ||
359 | init_waitqueue_entry(&__wait, current); \ | ||
360 | \ | ||
361 | add_wait_queue(&wq, &__wait); \ | ||
362 | for (;;) { \ | ||
363 | set_current_state(TASK_UNINTERRUPTIBLE); \ | ||
364 | if (condition) \ | ||
365 | break; \ | ||
366 | spin_unlock_irq(&lock); \ | ||
367 | cmd; \ | ||
368 | schedule(); \ | ||
369 | spin_lock_irq(&lock); \ | ||
370 | } \ | ||
371 | current->state = TASK_RUNNING; \ | ||
372 | remove_wait_queue(&wq, &__wait); \ | ||
373 | } while (0) | ||
374 | |||
375 | #define wait_event_lock_irq(wq, condition, lock, cmd) \ | ||
376 | do { \ | ||
377 | if (condition) \ | ||
378 | break; \ | ||
379 | __wait_event_lock_irq(wq, condition, lock, cmd); \ | ||
380 | } while (0) | ||
381 | |||
382 | static inline void safe_put_page(struct page *p) | ||
383 | { | ||
384 | if (p) put_page(p); | ||
385 | } | ||
386 | |||
387 | #endif /* CONFIG_BLOCK */ | ||
388 | #endif | ||
389 | |||
390 | |||
391 | extern int register_md_personality(struct mdk_personality *p); | ||
392 | extern int unregister_md_personality(struct mdk_personality *p); | ||
393 | extern mdk_thread_t * md_register_thread(void (*run) (mddev_t *mddev), | ||
394 | mddev_t *mddev, const char *name); | ||
395 | extern void md_unregister_thread(mdk_thread_t *thread); | ||
396 | extern void md_wakeup_thread(mdk_thread_t *thread); | ||
397 | extern void md_check_recovery(mddev_t *mddev); | ||
398 | extern void md_write_start(mddev_t *mddev, struct bio *bi); | ||
399 | extern void md_write_end(mddev_t *mddev); | ||
400 | extern void md_done_sync(mddev_t *mddev, int blocks, int ok); | ||
401 | extern void md_error(mddev_t *mddev, mdk_rdev_t *rdev); | ||
402 | |||
403 | extern void md_super_write(mddev_t *mddev, mdk_rdev_t *rdev, | ||
404 | sector_t sector, int size, struct page *page); | ||
405 | extern void md_super_wait(mddev_t *mddev); | ||
406 | extern int sync_page_io(struct block_device *bdev, sector_t sector, int size, | ||
407 | struct page *page, int rw); | ||
408 | extern void md_do_sync(mddev_t *mddev); | ||
409 | extern void md_new_event(mddev_t *mddev); | ||
410 | extern int md_allow_write(mddev_t *mddev); | ||
411 | extern void md_wait_for_blocked_rdev(mdk_rdev_t *rdev, mddev_t *mddev); | ||