Linux 2.6.23-rc1
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / include / linux / raid / md_k.h
CommitLineData
1da177e4
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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
06d91a5f
N
18/* and dm-bio-list.h is not under include/linux because.... ??? */
19#include "../../../drivers/md/dm-bio-list.h"
20
9361401e
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21#ifdef CONFIG_BLOCK
22
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23#define LEVEL_MULTIPATH (-4)
24#define LEVEL_LINEAR (-1)
25#define LEVEL_FAULTY (-5)
26
2604b703
N
27/* we need a value for 'no level specified' and 0
28 * means 'raid0', so we need something else. This is
29 * for internal use only
30 */
31#define LEVEL_NONE (-1000000)
32
1da177e4 33#define MaxSector (~(sector_t)0)
1da177e4 34
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35typedef struct mddev_s mddev_t;
36typedef struct mdk_rdev_s mdk_rdev_t;
37
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38/*
39 * options passed in raidrun:
40 */
41
e8703fe1 42/* Currently this must fit in an 'int' */
8932c2e0 43#define MAX_CHUNK_SIZE (1<<30)
1da177e4 44
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45/*
46 * MD's 'extended' device
47 */
48struct mdk_rdev_s
49{
50 struct list_head same_set; /* RAID devices within the same set */
51
52 sector_t size; /* Device size (in blocks) */
53 mddev_t *mddev; /* RAID array if running */
713f6ab1 54 long last_events; /* IO event timestamp */
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55
56 struct block_device *bdev; /* block device handle */
57
58 struct page *sb_page;
59 int sb_loaded;
42543769 60 __u64 sb_events;
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61 sector_t data_offset; /* start of data in array */
62 sector_t sb_offset;
0002b271 63 int sb_size; /* bytes in the superblock */
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64 int preferred_minor; /* autorun support */
65
86e6ffdd
N
66 struct kobject kobj;
67
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68 /* A device can be in one of three states based on two flags:
69 * Not working: faulty==1 in_sync==0
70 * Fully working: faulty==0 in_sync==1
71 * Working, but not
72 * in sync with array
73 * faulty==0 in_sync==0
74 *
75 * It can never have faulty==1, in_sync==1
76 * This reduces the burden of testing multiple flags in many cases
77 */
1da177e4 78
b2d444d7
N
79 unsigned long flags;
80#define Faulty 1 /* device is known to have a fault */
81#define In_sync 2 /* device is in_sync with rest of array */
8ddf9efe 82#define WriteMostly 4 /* Avoid reading if at all possible */
a9701a30 83#define BarriersNotsupp 5 /* BIO_RW_BARRIER is not supported */
8ddf9efe 84
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85 int desc_nr; /* descriptor index in the superblock */
86 int raid_disk; /* role of device in array */
41158c7e
N
87 int saved_raid_disk; /* role that device used to have in the
88 * array and could again if we did a partial
89 * resync from the bitmap
90 */
5fd6c1dc
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91 sector_t recovery_offset;/* If this device has been partially
92 * recovered, this is where we were
93 * up to.
94 */
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95
96 atomic_t nr_pending; /* number of pending requests.
97 * only maintained for arrays that
98 * support hot removal
99 */
ba22dcbf
N
100 atomic_t read_errors; /* number of consecutive read errors that
101 * we have tried to ignore.
102 */
4dbcdc75
N
103 atomic_t corrected_errors; /* number of corrected read errors,
104 * for reporting to userspace and storing
105 * in superblock.
106 */
5792a285 107 struct work_struct del_work; /* used for delayed sysfs removal */
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108};
109
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110struct mddev_s
111{
112 void *private;
2604b703 113 struct mdk_personality *pers;
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114 dev_t unit;
115 int md_minor;
116 struct list_head disks;
850b2b42
N
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
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122 int ro;
123
124 struct gendisk *gendisk;
125
eae1701f
N
126 struct kobject kobj;
127
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128 /* Superblock information */
129 int major_version,
130 minor_version,
131 patch_version;
132 int persistent;
133 int chunk_size;
134 time_t ctime, utime;
135 int level, layout;
d9d166c2 136 char clevel[16];
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137 int raid_disks;
138 int max_disks;
139 sector_t size; /* used size of component devices */
140 sector_t array_size; /* exported array size */
141 __u64 events;
142
143 char uuid[16];
144
f6705578
N
145 /* If the array is being reshaped, we need to record the
146 * new shape and an indication of where we are up to.
147 * This is written to the superblock.
148 * If reshape_position is MaxSector, then no reshape is happening (yet).
149 */
150 sector_t reshape_position;
151 int delta_disks, new_level, new_layout, new_chunk;
152
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153 struct mdk_thread_s *thread; /* management thread */
154 struct mdk_thread_s *sync_thread; /* doing resync or reconstruct */
ff4e8d9a 155 sector_t curr_resync; /* last block scheduled */
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156 unsigned long resync_mark; /* a recent timestamp */
157 sector_t resync_mark_cnt;/* blocks written at resync_mark */
ff4e8d9a 158 sector_t curr_mark_cnt; /* blocks scheduled now */
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159
160 sector_t resync_max_sectors; /* may be set by personality */
9d88883e
N
161
162 sector_t resync_mismatches; /* count of sectors where
163 * parity/replica mismatch found
164 */
e464eafd
N
165
166 /* allow user-space to request suspension of IO to regions of the array */
167 sector_t suspend_lo;
168 sector_t suspend_hi;
88202a0c
N
169 /* if zero, use the system-wide default */
170 int sync_speed_min;
171 int sync_speed_max;
172
6ff8d8ec 173 int ok_start_degraded;
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174 /* recovery/resync flags
175 * NEEDED: we might need to start a resync/recover
176 * RUNNING: a thread is running, or about to be started
177 * SYNC: actually doing a resync, not a recovery
178 * ERR: and IO error was detected - abort the resync/recovery
179 * INTR: someone requested a (clean) early abort.
180 * DONE: thread is done and is waiting to be reaped
24dd469d
N
181 * REQUEST: user-space has requested a sync (used with SYNC)
182 * CHECK: user-space request for for check-only, no repair
ccfcc3c1
N
183 * RESHAPE: A reshape is happening
184 *
185 * If neither SYNC or RESHAPE are set, then it is a recovery.
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186 */
187#define MD_RECOVERY_RUNNING 0
188#define MD_RECOVERY_SYNC 1
189#define MD_RECOVERY_ERR 2
190#define MD_RECOVERY_INTR 3
191#define MD_RECOVERY_DONE 4
192#define MD_RECOVERY_NEEDED 5
24dd469d
N
193#define MD_RECOVERY_REQUESTED 6
194#define MD_RECOVERY_CHECK 7
ccfcc3c1 195#define MD_RECOVERY_RESHAPE 8
5fd6c1dc
N
196#define MD_RECOVERY_FROZEN 9
197
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198 unsigned long recovery;
199
200 int in_sync; /* know to not need resync */
df5b89b3 201 struct mutex reconfig_mutex;
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202 atomic_t active;
203
44ce6294 204 int changed; /* true if we might need to reread partition info */
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205 int degraded; /* whether md should consider
206 * adding a spare
207 */
a9701a30
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208 int barriers_work; /* initialised to true, cleared as soon
209 * as a barrier request to slave
210 * fails. Only supported
211 */
212 struct bio *biolist; /* bios that need to be retried
213 * because BIO_RW_BARRIER is not supported
214 */
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215
216 atomic_t recovery_active; /* blocks scheduled, but not written */
217 wait_queue_head_t recovery_wait;
218 sector_t recovery_cp;
06d91a5f
N
219
220 spinlock_t write_lock;
3d310eb7 221 wait_queue_head_t sb_wait; /* for waiting on superblock updates */
7bfa19f2 222 atomic_t pending_writes; /* number of active superblock writes */
06d91a5f 223
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224 unsigned int safemode; /* if set, update "clean" superblock
225 * when no writes pending.
226 */
227 unsigned int safemode_delay;
228 struct timer_list safemode_timer;
229 atomic_t writes_pending;
230 request_queue_t *queue; /* for plugging ... */
231
4b6d287f
N
232 atomic_t write_behind; /* outstanding async IO */
233 unsigned int max_write_behind; /* 0 = sync */
234
32a7627c
N
235 struct bitmap *bitmap; /* the bitmap for the device */
236 struct file *bitmap_file; /* the bitmap file */
a654b9d8
N
237 long bitmap_offset; /* offset from superblock of
238 * start of bitmap. May be
239 * negative, but not '0'
240 */
36fa3063
N
241 long default_bitmap_offset; /* this is the offset to use when
242 * hot-adding a bitmap. It should
243 * eventually be settable by sysfs.
244 */
32a7627c 245
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246 struct list_head all_mddevs;
247};
248
249
250static inline void rdev_dec_pending(mdk_rdev_t *rdev, mddev_t *mddev)
251{
b2d444d7 252 int faulty = test_bit(Faulty, &rdev->flags);
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253 if (atomic_dec_and_test(&rdev->nr_pending) && faulty)
254 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
255}
256
257static inline void md_sync_acct(struct block_device *bdev, unsigned long nr_sectors)
258{
259 atomic_add(nr_sectors, &bdev->bd_contains->bd_disk->sync_io);
260}
261
2604b703 262struct mdk_personality
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263{
264 char *name;
2604b703
N
265 int level;
266 struct list_head list;
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267 struct module *owner;
268 int (*make_request)(request_queue_t *q, struct bio *bio);
269 int (*run)(mddev_t *mddev);
270 int (*stop)(mddev_t *mddev);
271 void (*status)(struct seq_file *seq, mddev_t *mddev);
272 /* error_handler must set ->faulty and clear ->in_sync
273 * if appropriate, and should abort recovery if needed
274 */
275 void (*error_handler)(mddev_t *mddev, mdk_rdev_t *rdev);
276 int (*hot_add_disk) (mddev_t *mddev, mdk_rdev_t *rdev);
277 int (*hot_remove_disk) (mddev_t *mddev, int number);
278 int (*spare_active) (mddev_t *mddev);
57afd89f 279 sector_t (*sync_request)(mddev_t *mddev, sector_t sector_nr, int *skipped, int go_faster);
1da177e4 280 int (*resize) (mddev_t *mddev, sector_t sectors);
63c70c4f
N
281 int (*check_reshape) (mddev_t *mddev);
282 int (*start_reshape) (mddev_t *mddev);
1da177e4 283 int (*reconfig) (mddev_t *mddev, int layout, int chunk_size);
36fa3063
N
284 /* quiesce moves between quiescence states
285 * 0 - fully active
286 * 1 - no new requests allowed
287 * others - reserved
288 */
289 void (*quiesce) (mddev_t *mddev, int state);
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290};
291
292
007583c9
N
293struct md_sysfs_entry {
294 struct attribute attr;
295 ssize_t (*show)(mddev_t *, char *);
296 ssize_t (*store)(mddev_t *, const char *, size_t);
297};
298
299
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300static inline char * mdname (mddev_t * mddev)
301{
302 return mddev->gendisk ? mddev->gendisk->disk_name : "mdX";
303}
304
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305/*
306 * iterates through some rdev ringlist. It's safe to remove the
307 * current 'rdev'. Dont touch 'tmp' though.
308 */
309#define ITERATE_RDEV_GENERIC(head,rdev,tmp) \
310 \
311 for ((tmp) = (head).next; \
312 (rdev) = (list_entry((tmp), mdk_rdev_t, same_set)), \
313 (tmp) = (tmp)->next, (tmp)->prev != &(head) \
314 ; )
315/*
316 * iterates through the 'same array disks' ringlist
317 */
318#define ITERATE_RDEV(mddev,rdev,tmp) \
319 ITERATE_RDEV_GENERIC((mddev)->disks,rdev,tmp)
320
321/*
322 * Iterates through 'pending RAID disks'
323 */
324#define ITERATE_RDEV_PENDING(rdev,tmp) \
325 ITERATE_RDEV_GENERIC(pending_raid_disks,rdev,tmp)
326
327typedef struct mdk_thread_s {
328 void (*run) (mddev_t *mddev);
329 mddev_t *mddev;
330 wait_queue_head_t wqueue;
331 unsigned long flags;
1da177e4 332 struct task_struct *tsk;
32a7627c 333 unsigned long timeout;
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334} mdk_thread_t;
335
336#define THREAD_WAKEUP 0
337
338#define __wait_event_lock_irq(wq, condition, lock, cmd) \
339do { \
340 wait_queue_t __wait; \
341 init_waitqueue_entry(&__wait, current); \
342 \
343 add_wait_queue(&wq, &__wait); \
344 for (;;) { \
345 set_current_state(TASK_UNINTERRUPTIBLE); \
346 if (condition) \
347 break; \
348 spin_unlock_irq(&lock); \
349 cmd; \
350 schedule(); \
351 spin_lock_irq(&lock); \
352 } \
353 current->state = TASK_RUNNING; \
354 remove_wait_queue(&wq, &__wait); \
355} while (0)
356
357#define wait_event_lock_irq(wq, condition, lock, cmd) \
358do { \
359 if (condition) \
360 break; \
361 __wait_event_lock_irq(wq, condition, lock, cmd); \
362} while (0)
363
1345b1d8
N
364static inline void safe_put_page(struct page *p)
365{
366 if (p) put_page(p);
367}
368
9361401e 369#endif /* CONFIG_BLOCK */
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370#endif
371