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authorChristoph Hellwig <hch@lst.de>2009-03-30 23:27:03 -0400
committerNeilBrown <neilb@suse.de>2009-03-30 23:27:03 -0400
commitef740c372dfd80e706dbf955d4e4aedda6c0c148 (patch)
tree8d9ef9db346ee1ba319a125c9de83cdde049510d /include/linux/raid
parent2a40a8aed083d988df6822bb9b1b08fb7ce21e1d (diff)
md: move headers out of include/linux/raid/
Move the headers with the local structures for the disciplines and bitmap.h into drivers/md/ so that they are more easily grepable for hacking and not far away. md.h is left where it is for now as there are some uses from the outside. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: NeilBrown <neilb@suse.de>
Diffstat (limited to 'include/linux/raid')
-rw-r--r--include/linux/raid/bitmap.h288
-rw-r--r--include/linux/raid/linear.h31
-rw-r--r--include/linux/raid/multipath.h42
-rw-r--r--include/linux/raid/raid0.h30
-rw-r--r--include/linux/raid/raid1.h134
-rw-r--r--include/linux/raid/raid10.h123
-rw-r--r--include/linux/raid/raid5.h402
7 files changed, 0 insertions, 1050 deletions
diff --git a/include/linux/raid/bitmap.h b/include/linux/raid/bitmap.h
deleted file mode 100644
index e98900671ca..00000000000
--- a/include/linux/raid/bitmap.h
+++ /dev/null
@@ -1,288 +0,0 @@
1/*
2 * bitmap.h: Copyright (C) Peter T. Breuer (ptb@ot.uc3m.es) 2003
3 *
4 * additions: Copyright (C) 2003-2004, Paul Clements, SteelEye Technology, Inc.
5 */
6#ifndef BITMAP_H
7#define BITMAP_H 1
8
9#define BITMAP_MAJOR_LO 3
10/* version 4 insists the bitmap is in little-endian order
11 * with version 3, it is host-endian which is non-portable
12 */
13#define BITMAP_MAJOR_HI 4
14#define BITMAP_MAJOR_HOSTENDIAN 3
15
16#define BITMAP_MINOR 39
17
18/*
19 * in-memory bitmap:
20 *
21 * Use 16 bit block counters to track pending writes to each "chunk".
22 * The 2 high order bits are special-purpose, the first is a flag indicating
23 * whether a resync is needed. The second is a flag indicating whether a
24 * resync is active.
25 * This means that the counter is actually 14 bits:
26 *
27 * +--------+--------+------------------------------------------------+
28 * | resync | resync | counter |
29 * | needed | active | |
30 * | (0-1) | (0-1) | (0-16383) |
31 * +--------+--------+------------------------------------------------+
32 *
33 * The "resync needed" bit is set when:
34 * a '1' bit is read from storage at startup.
35 * a write request fails on some drives
36 * a resync is aborted on a chunk with 'resync active' set
37 * It is cleared (and resync-active set) when a resync starts across all drives
38 * of the chunk.
39 *
40 *
41 * The "resync active" bit is set when:
42 * a resync is started on all drives, and resync_needed is set.
43 * resync_needed will be cleared (as long as resync_active wasn't already set).
44 * It is cleared when a resync completes.
45 *
46 * The counter counts pending write requests, plus the on-disk bit.
47 * When the counter is '1' and the resync bits are clear, the on-disk
48 * bit can be cleared aswell, thus setting the counter to 0.
49 * When we set a bit, or in the counter (to start a write), if the fields is
50 * 0, we first set the disk bit and set the counter to 1.
51 *
52 * If the counter is 0, the on-disk bit is clear and the stipe is clean
53 * Anything that dirties the stipe pushes the counter to 2 (at least)
54 * and sets the on-disk bit (lazily).
55 * If a periodic sweep find the counter at 2, it is decremented to 1.
56 * If the sweep find the counter at 1, the on-disk bit is cleared and the
57 * counter goes to zero.
58 *
59 * Also, we'll hijack the "map" pointer itself and use it as two 16 bit block
60 * counters as a fallback when "page" memory cannot be allocated:
61 *
62 * Normal case (page memory allocated):
63 *
64 * page pointer (32-bit)
65 *
66 * [ ] ------+
67 * |
68 * +-------> [ ][ ]..[ ] (4096 byte page == 2048 counters)
69 * c1 c2 c2048
70 *
71 * Hijacked case (page memory allocation failed):
72 *
73 * hijacked page pointer (32-bit)
74 *
75 * [ ][ ] (no page memory allocated)
76 * counter #1 (16-bit) counter #2 (16-bit)
77 *
78 */
79
80#ifdef __KERNEL__
81
82#define PAGE_BITS (PAGE_SIZE << 3)
83#define PAGE_BIT_SHIFT (PAGE_SHIFT + 3)
84
85typedef __u16 bitmap_counter_t;
86#define COUNTER_BITS 16
87#define COUNTER_BIT_SHIFT 4
88#define COUNTER_BYTE_RATIO (COUNTER_BITS / 8)
89#define COUNTER_BYTE_SHIFT (COUNTER_BIT_SHIFT - 3)
90
91#define NEEDED_MASK ((bitmap_counter_t) (1 << (COUNTER_BITS - 1)))
92#define RESYNC_MASK ((bitmap_counter_t) (1 << (COUNTER_BITS - 2)))
93#define COUNTER_MAX ((bitmap_counter_t) RESYNC_MASK - 1)
94#define NEEDED(x) (((bitmap_counter_t) x) & NEEDED_MASK)
95#define RESYNC(x) (((bitmap_counter_t) x) & RESYNC_MASK)
96#define COUNTER(x) (((bitmap_counter_t) x) & COUNTER_MAX)
97
98/* how many counters per page? */
99#define PAGE_COUNTER_RATIO (PAGE_BITS / COUNTER_BITS)
100/* same, except a shift value for more efficient bitops */
101#define PAGE_COUNTER_SHIFT (PAGE_BIT_SHIFT - COUNTER_BIT_SHIFT)
102/* same, except a mask value for more efficient bitops */
103#define PAGE_COUNTER_MASK (PAGE_COUNTER_RATIO - 1)
104
105#define BITMAP_BLOCK_SIZE 512
106#define BITMAP_BLOCK_SHIFT 9
107
108/* how many blocks per chunk? (this is variable) */
109#define CHUNK_BLOCK_RATIO(bitmap) ((bitmap)->chunksize >> BITMAP_BLOCK_SHIFT)
110#define CHUNK_BLOCK_SHIFT(bitmap) ((bitmap)->chunkshift - BITMAP_BLOCK_SHIFT)
111#define CHUNK_BLOCK_MASK(bitmap) (CHUNK_BLOCK_RATIO(bitmap) - 1)
112
113/* when hijacked, the counters and bits represent even larger "chunks" */
114/* there will be 1024 chunks represented by each counter in the page pointers */
115#define PAGEPTR_BLOCK_RATIO(bitmap) \
116 (CHUNK_BLOCK_RATIO(bitmap) << PAGE_COUNTER_SHIFT >> 1)
117#define PAGEPTR_BLOCK_SHIFT(bitmap) \
118 (CHUNK_BLOCK_SHIFT(bitmap) + PAGE_COUNTER_SHIFT - 1)
119#define PAGEPTR_BLOCK_MASK(bitmap) (PAGEPTR_BLOCK_RATIO(bitmap) - 1)
120
121/*
122 * on-disk bitmap:
123 *
124 * Use one bit per "chunk" (block set). We do the disk I/O on the bitmap
125 * file a page at a time. There's a superblock at the start of the file.
126 */
127
128/* map chunks (bits) to file pages - offset by the size of the superblock */
129#define CHUNK_BIT_OFFSET(chunk) ((chunk) + (sizeof(bitmap_super_t) << 3))
130
131#endif
132
133/*
134 * bitmap structures:
135 */
136
137#define BITMAP_MAGIC 0x6d746962
138
139/* use these for bitmap->flags and bitmap->sb->state bit-fields */
140enum bitmap_state {
141 BITMAP_STALE = 0x002, /* the bitmap file is out of date or had -EIO */
142 BITMAP_WRITE_ERROR = 0x004, /* A write error has occurred */
143 BITMAP_HOSTENDIAN = 0x8000,
144};
145
146/* the superblock at the front of the bitmap file -- little endian */
147typedef struct bitmap_super_s {
148 __le32 magic; /* 0 BITMAP_MAGIC */
149 __le32 version; /* 4 the bitmap major for now, could change... */
150 __u8 uuid[16]; /* 8 128 bit uuid - must match md device uuid */
151 __le64 events; /* 24 event counter for the bitmap (1)*/
152 __le64 events_cleared;/*32 event counter when last bit cleared (2) */
153 __le64 sync_size; /* 40 the size of the md device's sync range(3) */
154 __le32 state; /* 48 bitmap state information */
155 __le32 chunksize; /* 52 the bitmap chunk size in bytes */
156 __le32 daemon_sleep; /* 56 seconds between disk flushes */
157 __le32 write_behind; /* 60 number of outstanding write-behind writes */
158
159 __u8 pad[256 - 64]; /* set to zero */
160} bitmap_super_t;
161
162/* notes:
163 * (1) This event counter is updated before the eventcounter in the md superblock
164 * When a bitmap is loaded, it is only accepted if this event counter is equal
165 * to, or one greater than, the event counter in the superblock.
166 * (2) This event counter is updated when the other one is *if*and*only*if* the
167 * array is not degraded. As bits are not cleared when the array is degraded,
168 * this represents the last time that any bits were cleared.
169 * If a device is being added that has an event count with this value or
170 * higher, it is accepted as conforming to the bitmap.
171 * (3)This is the number of sectors represented by the bitmap, and is the range that
172 * resync happens across. For raid1 and raid5/6 it is the size of individual
173 * devices. For raid10 it is the size of the array.
174 */
175
176#ifdef __KERNEL__
177
178/* the in-memory bitmap is represented by bitmap_pages */
179struct bitmap_page {
180 /*
181 * map points to the actual memory page
182 */
183 char *map;
184 /*
185 * in emergencies (when map cannot be alloced), hijack the map
186 * pointer and use it as two counters itself
187 */
188 unsigned int hijacked:1;
189 /*
190 * count of dirty bits on the page
191 */
192 unsigned int count:31;
193};
194
195/* keep track of bitmap file pages that have pending writes on them */
196struct page_list {
197 struct list_head list;
198 struct page *page;
199};
200
201/* the main bitmap structure - one per mddev */
202struct bitmap {
203 struct bitmap_page *bp;
204 unsigned long pages; /* total number of pages in the bitmap */
205 unsigned long missing_pages; /* number of pages not yet allocated */
206
207 mddev_t *mddev; /* the md device that the bitmap is for */
208
209 int counter_bits; /* how many bits per block counter */
210
211 /* bitmap chunksize -- how much data does each bit represent? */
212 unsigned long chunksize;
213 unsigned long chunkshift; /* chunksize = 2^chunkshift (for bitops) */
214 unsigned long chunks; /* total number of data chunks for the array */
215
216 /* We hold a count on the chunk currently being synced, and drop
217 * it when the last block is started. If the resync is aborted
218 * midway, we need to be able to drop that count, so we remember
219 * the counted chunk..
220 */
221 unsigned long syncchunk;
222
223 __u64 events_cleared;
224 int need_sync;
225
226 /* bitmap spinlock */
227 spinlock_t lock;
228
229 long offset; /* offset from superblock if file is NULL */
230 struct file *file; /* backing disk file */
231 struct page *sb_page; /* cached copy of the bitmap file superblock */
232 struct page **filemap; /* list of cache pages for the file */
233 unsigned long *filemap_attr; /* attributes associated w/ filemap pages */
234 unsigned long file_pages; /* number of pages in the file */
235 int last_page_size; /* bytes in the last page */
236
237 unsigned long flags;
238
239 int allclean;
240
241 unsigned long max_write_behind; /* write-behind mode */
242 atomic_t behind_writes;
243
244 /*
245 * the bitmap daemon - periodically wakes up and sweeps the bitmap
246 * file, cleaning up bits and flushing out pages to disk as necessary
247 */
248 unsigned long daemon_lastrun; /* jiffies of last run */
249 unsigned long daemon_sleep; /* how many seconds between updates? */
250 unsigned long last_end_sync; /* when we lasted called end_sync to
251 * update bitmap with resync progress */
252
253 atomic_t pending_writes; /* pending writes to the bitmap file */
254 wait_queue_head_t write_wait;
255 wait_queue_head_t overflow_wait;
256
257};
258
259/* the bitmap API */
260
261/* these are used only by md/bitmap */
262int bitmap_create(mddev_t *mddev);
263void bitmap_flush(mddev_t *mddev);
264void bitmap_destroy(mddev_t *mddev);
265
266void bitmap_print_sb(struct bitmap *bitmap);
267void bitmap_update_sb(struct bitmap *bitmap);
268
269int bitmap_setallbits(struct bitmap *bitmap);
270void bitmap_write_all(struct bitmap *bitmap);
271
272void bitmap_dirty_bits(struct bitmap *bitmap, unsigned long s, unsigned long e);
273
274/* these are exported */
275int bitmap_startwrite(struct bitmap *bitmap, sector_t offset,
276 unsigned long sectors, int behind);
277void bitmap_endwrite(struct bitmap *bitmap, sector_t offset,
278 unsigned long sectors, int success, int behind);
279int bitmap_start_sync(struct bitmap *bitmap, sector_t offset, int *blocks, int degraded);
280void bitmap_end_sync(struct bitmap *bitmap, sector_t offset, int *blocks, int aborted);
281void bitmap_close_sync(struct bitmap *bitmap);
282void bitmap_cond_end_sync(struct bitmap *bitmap, sector_t sector);
283
284void bitmap_unplug(struct bitmap *bitmap);
285void bitmap_daemon_work(struct bitmap *bitmap);
286#endif
287
288#endif
diff --git a/include/linux/raid/linear.h b/include/linux/raid/linear.h
deleted file mode 100644
index f38b9c586af..00000000000
--- a/include/linux/raid/linear.h
+++ /dev/null
@@ -1,31 +0,0 @@
1#ifndef _LINEAR_H
2#define _LINEAR_H
3
4#include <linux/raid/md.h>
5
6struct dev_info {
7 mdk_rdev_t *rdev;
8 sector_t num_sectors;
9 sector_t start_sector;
10};
11
12typedef struct dev_info dev_info_t;
13
14struct linear_private_data
15{
16 struct linear_private_data *prev; /* earlier version */
17 dev_info_t **hash_table;
18 sector_t spacing;
19 sector_t array_sectors;
20 int sector_shift; /* shift before dividing
21 * by spacing
22 */
23 dev_info_t disks[0];
24};
25
26
27typedef struct linear_private_data linear_conf_t;
28
29#define mddev_to_conf(mddev) ((linear_conf_t *) mddev->private)
30
31#endif
diff --git a/include/linux/raid/multipath.h b/include/linux/raid/multipath.h
deleted file mode 100644
index 6f53fc177a4..00000000000
--- a/include/linux/raid/multipath.h
+++ /dev/null
@@ -1,42 +0,0 @@
1#ifndef _MULTIPATH_H
2#define _MULTIPATH_H
3
4#include <linux/raid/md.h>
5
6struct multipath_info {
7 mdk_rdev_t *rdev;
8};
9
10struct multipath_private_data {
11 mddev_t *mddev;
12 struct multipath_info *multipaths;
13 int raid_disks;
14 int working_disks;
15 spinlock_t device_lock;
16 struct list_head retry_list;
17
18 mempool_t *pool;
19};
20
21typedef struct multipath_private_data multipath_conf_t;
22
23/*
24 * this is the only point in the RAID code where we violate
25 * C type safety. mddev->private is an 'opaque' pointer.
26 */
27#define mddev_to_conf(mddev) ((multipath_conf_t *) mddev->private)
28
29/*
30 * this is our 'private' 'collective' MULTIPATH buffer head.
31 * it contains information about what kind of IO operations were started
32 * for this MULTIPATH operation, and about their status:
33 */
34
35struct multipath_bh {
36 mddev_t *mddev;
37 struct bio *master_bio;
38 struct bio bio;
39 int path;
40 struct list_head retry_list;
41};
42#endif
diff --git a/include/linux/raid/raid0.h b/include/linux/raid/raid0.h
deleted file mode 100644
index fd42aa87c39..00000000000
--- a/include/linux/raid/raid0.h
+++ /dev/null
@@ -1,30 +0,0 @@
1#ifndef _RAID0_H
2#define _RAID0_H
3
4#include <linux/raid/md.h>
5
6struct strip_zone
7{
8 sector_t zone_start; /* Zone offset in md_dev (in sectors) */
9 sector_t dev_start; /* Zone offset in real dev (in sectors) */
10 sector_t sectors; /* Zone size in sectors */
11 int nb_dev; /* # of devices attached to the zone */
12 mdk_rdev_t **dev; /* Devices attached to the zone */
13};
14
15struct raid0_private_data
16{
17 struct strip_zone **hash_table; /* Table of indexes into strip_zone */
18 struct strip_zone *strip_zone;
19 mdk_rdev_t **devlist; /* lists of rdevs, pointed to by strip_zone->dev */
20 int nr_strip_zones;
21
22 sector_t spacing;
23 int sector_shift; /* shift this before divide by spacing */
24};
25
26typedef struct raid0_private_data raid0_conf_t;
27
28#define mddev_to_conf(mddev) ((raid0_conf_t *) mddev->private)
29
30#endif
diff --git a/include/linux/raid/raid1.h b/include/linux/raid/raid1.h
deleted file mode 100644
index 0a9ba7c3302..00000000000
--- a/include/linux/raid/raid1.h
+++ /dev/null
@@ -1,134 +0,0 @@
1#ifndef _RAID1_H
2#define _RAID1_H
3
4#include <linux/raid/md.h>
5
6typedef struct mirror_info mirror_info_t;
7
8struct mirror_info {
9 mdk_rdev_t *rdev;
10 sector_t head_position;
11};
12
13/*
14 * memory pools need a pointer to the mddev, so they can force an unplug
15 * when memory is tight, and a count of the number of drives that the
16 * pool was allocated for, so they know how much to allocate and free.
17 * mddev->raid_disks cannot be used, as it can change while a pool is active
18 * These two datums are stored in a kmalloced struct.
19 */
20
21struct pool_info {
22 mddev_t *mddev;
23 int raid_disks;
24};
25
26
27typedef struct r1bio_s r1bio_t;
28
29struct r1_private_data_s {
30 mddev_t *mddev;
31 mirror_info_t *mirrors;
32 int raid_disks;
33 int last_used;
34 sector_t next_seq_sect;
35 spinlock_t device_lock;
36
37 struct list_head retry_list;
38 /* queue pending writes and submit them on unplug */
39 struct bio_list pending_bio_list;
40 /* queue of writes that have been unplugged */
41 struct bio_list flushing_bio_list;
42
43 /* for use when syncing mirrors: */
44
45 spinlock_t resync_lock;
46 int nr_pending;
47 int nr_waiting;
48 int nr_queued;
49 int barrier;
50 sector_t next_resync;
51 int fullsync; /* set to 1 if a full sync is needed,
52 * (fresh device added).
53 * Cleared when a sync completes.
54 */
55
56 wait_queue_head_t wait_barrier;
57
58 struct pool_info *poolinfo;
59
60 struct page *tmppage;
61
62 mempool_t *r1bio_pool;
63 mempool_t *r1buf_pool;
64};
65
66typedef struct r1_private_data_s conf_t;
67
68/*
69 * this is the only point in the RAID code where we violate
70 * C type safety. mddev->private is an 'opaque' pointer.
71 */
72#define mddev_to_conf(mddev) ((conf_t *) mddev->private)
73
74/*
75 * this is our 'private' RAID1 bio.
76 *
77 * it contains information about what kind of IO operations were started
78 * for this RAID1 operation, and about their status:
79 */
80
81struct r1bio_s {
82 atomic_t remaining; /* 'have we finished' count,
83 * used from IRQ handlers
84 */
85 atomic_t behind_remaining; /* number of write-behind ios remaining
86 * in this BehindIO request
87 */
88 sector_t sector;
89 int sectors;
90 unsigned long state;
91 mddev_t *mddev;
92 /*
93 * original bio going to /dev/mdx
94 */
95 struct bio *master_bio;
96 /*
97 * if the IO is in READ direction, then this is where we read
98 */
99 int read_disk;
100
101 struct list_head retry_list;
102 struct bitmap_update *bitmap_update;
103 /*
104 * if the IO is in WRITE direction, then multiple bios are used.
105 * We choose the number when they are allocated.
106 */
107 struct bio *bios[0];
108 /* DO NOT PUT ANY NEW FIELDS HERE - bios array is contiguously alloced*/
109};
110
111/* when we get a read error on a read-only array, we redirect to another
112 * device without failing the first device, or trying to over-write to
113 * correct the read error. To keep track of bad blocks on a per-bio
114 * level, we store IO_BLOCKED in the appropriate 'bios' pointer
115 */
116#define IO_BLOCKED ((struct bio*)1)
117
118/* bits for r1bio.state */
119#define R1BIO_Uptodate 0
120#define R1BIO_IsSync 1
121#define R1BIO_Degraded 2
122#define R1BIO_BehindIO 3
123#define R1BIO_Barrier 4
124#define R1BIO_BarrierRetry 5
125/* For write-behind requests, we call bi_end_io when
126 * the last non-write-behind device completes, providing
127 * any write was successful. Otherwise we call when
128 * any write-behind write succeeds, otherwise we call
129 * with failure when last write completes (and all failed).
130 * Record that bi_end_io was called with this flag...
131 */
132#define R1BIO_Returned 6
133
134#endif
diff --git a/include/linux/raid/raid10.h b/include/linux/raid/raid10.h
deleted file mode 100644
index e9091cfeb28..00000000000
--- a/include/linux/raid/raid10.h
+++ /dev/null
@@ -1,123 +0,0 @@
1#ifndef _RAID10_H
2#define _RAID10_H
3
4#include <linux/raid/md.h>
5
6typedef struct mirror_info mirror_info_t;
7
8struct mirror_info {
9 mdk_rdev_t *rdev;
10 sector_t head_position;
11};
12
13typedef struct r10bio_s r10bio_t;
14
15struct r10_private_data_s {
16 mddev_t *mddev;
17 mirror_info_t *mirrors;
18 int raid_disks;
19 spinlock_t device_lock;
20
21 /* geometry */
22 int near_copies; /* number of copies layed out raid0 style */
23 int far_copies; /* number of copies layed out
24 * at large strides across drives
25 */
26 int far_offset; /* far_copies are offset by 1 stripe
27 * instead of many
28 */
29 int copies; /* near_copies * far_copies.
30 * must be <= raid_disks
31 */
32 sector_t stride; /* distance between far copies.
33 * This is size / far_copies unless
34 * far_offset, in which case it is
35 * 1 stripe.
36 */
37
38 int chunk_shift; /* shift from chunks to sectors */
39 sector_t chunk_mask;
40
41 struct list_head retry_list;
42 /* queue pending writes and submit them on unplug */
43 struct bio_list pending_bio_list;
44
45
46 spinlock_t resync_lock;
47 int nr_pending;
48 int nr_waiting;
49 int nr_queued;
50 int barrier;
51 sector_t next_resync;
52 int fullsync; /* set to 1 if a full sync is needed,
53 * (fresh device added).
54 * Cleared when a sync completes.
55 */
56
57 wait_queue_head_t wait_barrier;
58
59 mempool_t *r10bio_pool;
60 mempool_t *r10buf_pool;
61 struct page *tmppage;
62};
63
64typedef struct r10_private_data_s conf_t;
65
66/*
67 * this is the only point in the RAID code where we violate
68 * C type safety. mddev->private is an 'opaque' pointer.
69 */
70#define mddev_to_conf(mddev) ((conf_t *) mddev->private)
71
72/*
73 * this is our 'private' RAID10 bio.
74 *
75 * it contains information about what kind of IO operations were started
76 * for this RAID10 operation, and about their status:
77 */
78
79struct r10bio_s {
80 atomic_t remaining; /* 'have we finished' count,
81 * used from IRQ handlers
82 */
83 sector_t sector; /* virtual sector number */
84 int sectors;
85 unsigned long state;
86 mddev_t *mddev;
87 /*
88 * original bio going to /dev/mdx
89 */
90 struct bio *master_bio;
91 /*
92 * if the IO is in READ direction, then this is where we read
93 */
94 int read_slot;
95
96 struct list_head retry_list;
97 /*
98 * if the IO is in WRITE direction, then multiple bios are used,
99 * one for each copy.
100 * When resyncing we also use one for each copy.
101 * When reconstructing, we use 2 bios, one for read, one for write.
102 * We choose the number when they are allocated.
103 */
104 struct {
105 struct bio *bio;
106 sector_t addr;
107 int devnum;
108 } devs[0];
109};
110
111/* when we get a read error on a read-only array, we redirect to another
112 * device without failing the first device, or trying to over-write to
113 * correct the read error. To keep track of bad blocks on a per-bio
114 * level, we store IO_BLOCKED in the appropriate 'bios' pointer
115 */
116#define IO_BLOCKED ((struct bio*)1)
117
118/* bits for r10bio.state */
119#define R10BIO_Uptodate 0
120#define R10BIO_IsSync 1
121#define R10BIO_IsRecover 2
122#define R10BIO_Degraded 3
123#endif
diff --git a/include/linux/raid/raid5.h b/include/linux/raid/raid5.h
deleted file mode 100644
index 3b267279245..00000000000
--- a/include/linux/raid/raid5.h
+++ /dev/null
@@ -1,402 +0,0 @@
1#ifndef _RAID5_H
2#define _RAID5_H
3
4#include <linux/raid/md.h>
5#include <linux/raid/xor.h>
6
7/*
8 *
9 * Each stripe contains one buffer per disc. Each buffer can be in
10 * one of a number of states stored in "flags". Changes between
11 * these states happen *almost* exclusively under a per-stripe
12 * spinlock. Some very specific changes can happen in bi_end_io, and
13 * these are not protected by the spin lock.
14 *
15 * The flag bits that are used to represent these states are:
16 * R5_UPTODATE and R5_LOCKED
17 *
18 * State Empty == !UPTODATE, !LOCK
19 * We have no data, and there is no active request
20 * State Want == !UPTODATE, LOCK
21 * A read request is being submitted for this block
22 * State Dirty == UPTODATE, LOCK
23 * Some new data is in this buffer, and it is being written out
24 * State Clean == UPTODATE, !LOCK
25 * We have valid data which is the same as on disc
26 *
27 * The possible state transitions are:
28 *
29 * Empty -> Want - on read or write to get old data for parity calc
30 * Empty -> Dirty - on compute_parity to satisfy write/sync request.(RECONSTRUCT_WRITE)
31 * Empty -> Clean - on compute_block when computing a block for failed drive
32 * Want -> Empty - on failed read
33 * Want -> Clean - on successful completion of read request
34 * Dirty -> Clean - on successful completion of write request
35 * Dirty -> Clean - on failed write
36 * Clean -> Dirty - on compute_parity to satisfy write/sync (RECONSTRUCT or RMW)
37 *
38 * The Want->Empty, Want->Clean, Dirty->Clean, transitions
39 * all happen in b_end_io at interrupt time.
40 * Each sets the Uptodate bit before releasing the Lock bit.
41 * This leaves one multi-stage transition:
42 * Want->Dirty->Clean
43 * This is safe because thinking that a Clean buffer is actually dirty
44 * will at worst delay some action, and the stripe will be scheduled
45 * for attention after the transition is complete.
46 *
47 * There is one possibility that is not covered by these states. That
48 * is if one drive has failed and there is a spare being rebuilt. We
49 * can't distinguish between a clean block that has been generated
50 * from parity calculations, and a clean block that has been
51 * successfully written to the spare ( or to parity when resyncing).
52 * To distingush these states we have a stripe bit STRIPE_INSYNC that
53 * is set whenever a write is scheduled to the spare, or to the parity
54 * disc if there is no spare. A sync request clears this bit, and
55 * when we find it set with no buffers locked, we know the sync is
56 * complete.
57 *
58 * Buffers for the md device that arrive via make_request are attached
59 * to the appropriate stripe in one of two lists linked on b_reqnext.
60 * One list (bh_read) for read requests, one (bh_write) for write.
61 * There should never be more than one buffer on the two lists
62 * together, but we are not guaranteed of that so we allow for more.
63 *
64 * If a buffer is on the read list when the associated cache buffer is
65 * Uptodate, the data is copied into the read buffer and it's b_end_io
66 * routine is called. This may happen in the end_request routine only
67 * if the buffer has just successfully been read. end_request should
68 * remove the buffers from the list and then set the Uptodate bit on
69 * the buffer. Other threads may do this only if they first check
70 * that the Uptodate bit is set. Once they have checked that they may
71 * take buffers off the read queue.
72 *
73 * When a buffer on the write list is committed for write it is copied
74 * into the cache buffer, which is then marked dirty, and moved onto a
75 * third list, the written list (bh_written). Once both the parity
76 * block and the cached buffer are successfully written, any buffer on
77 * a written list can be returned with b_end_io.
78 *
79 * The write list and read list both act as fifos. The read list is
80 * protected by the device_lock. The write and written lists are
81 * protected by the stripe lock. The device_lock, which can be
82 * claimed while the stipe lock is held, is only for list
83 * manipulations and will only be held for a very short time. It can
84 * be claimed from interrupts.
85 *
86 *
87 * Stripes in the stripe cache can be on one of two lists (or on
88 * neither). The "inactive_list" contains stripes which are not
89 * currently being used for any request. They can freely be reused
90 * for another stripe. The "handle_list" contains stripes that need
91 * to be handled in some way. Both of these are fifo queues. Each
92 * stripe is also (potentially) linked to a hash bucket in the hash
93 * table so that it can be found by sector number. Stripes that are
94 * not hashed must be on the inactive_list, and will normally be at
95 * the front. All stripes start life this way.
96 *
97 * The inactive_list, handle_list and hash bucket lists are all protected by the
98 * device_lock.
99 * - stripes on the inactive_list never have their stripe_lock held.
100 * - stripes have a reference counter. If count==0, they are on a list.
101 * - If a stripe might need handling, STRIPE_HANDLE is set.
102 * - When refcount reaches zero, then if STRIPE_HANDLE it is put on
103 * handle_list else inactive_list
104 *
105 * This, combined with the fact that STRIPE_HANDLE is only ever
106 * cleared while a stripe has a non-zero count means that if the
107 * refcount is 0 and STRIPE_HANDLE is set, then it is on the
108 * handle_list and if recount is 0 and STRIPE_HANDLE is not set, then
109 * the stripe is on inactive_list.
110 *
111 * The possible transitions are:
112 * activate an unhashed/inactive stripe (get_active_stripe())
113 * lockdev check-hash unlink-stripe cnt++ clean-stripe hash-stripe unlockdev
114 * activate a hashed, possibly active stripe (get_active_stripe())
115 * lockdev check-hash if(!cnt++)unlink-stripe unlockdev
116 * attach a request to an active stripe (add_stripe_bh())
117 * lockdev attach-buffer unlockdev
118 * handle a stripe (handle_stripe())
119 * lockstripe clrSTRIPE_HANDLE ...
120 * (lockdev check-buffers unlockdev) ..
121 * change-state ..
122 * record io/ops needed unlockstripe schedule io/ops
123 * release an active stripe (release_stripe())
124 * lockdev if (!--cnt) { if STRIPE_HANDLE, add to handle_list else add to inactive-list } unlockdev
125 *
126 * The refcount counts each thread that have activated the stripe,
127 * plus raid5d if it is handling it, plus one for each active request
128 * on a cached buffer, and plus one if the stripe is undergoing stripe
129 * operations.
130 *
131 * Stripe operations are performed outside the stripe lock,
132 * the stripe operations are:
133 * -copying data between the stripe cache and user application buffers
134 * -computing blocks to save a disk access, or to recover a missing block
135 * -updating the parity on a write operation (reconstruct write and
136 * read-modify-write)
137 * -checking parity correctness
138 * -running i/o to disk
139 * These operations are carried out by raid5_run_ops which uses the async_tx
140 * api to (optionally) offload operations to dedicated hardware engines.
141 * When requesting an operation handle_stripe sets the pending bit for the
142 * operation and increments the count. raid5_run_ops is then run whenever
143 * the count is non-zero.
144 * There are some critical dependencies between the operations that prevent some
145 * from being requested while another is in flight.
146 * 1/ Parity check operations destroy the in cache version of the parity block,
147 * so we prevent parity dependent operations like writes and compute_blocks
148 * from starting while a check is in progress. Some dma engines can perform
149 * the check without damaging the parity block, in these cases the parity
150 * block is re-marked up to date (assuming the check was successful) and is
151 * not re-read from disk.
152 * 2/ When a write operation is requested we immediately lock the affected
153 * blocks, and mark them as not up to date. This causes new read requests
154 * to be held off, as well as parity checks and compute block operations.
155 * 3/ Once a compute block operation has been requested handle_stripe treats
156 * that block as if it is up to date. raid5_run_ops guaruntees that any
157 * operation that is dependent on the compute block result is initiated after
158 * the compute block completes.
159 */
160
161/*
162 * Operations state - intermediate states that are visible outside of sh->lock
163 * In general _idle indicates nothing is running, _run indicates a data
164 * processing operation is active, and _result means the data processing result
165 * is stable and can be acted upon. For simple operations like biofill and
166 * compute that only have an _idle and _run state they are indicated with
167 * sh->state flags (STRIPE_BIOFILL_RUN and STRIPE_COMPUTE_RUN)
168 */
169/**
170 * enum check_states - handles syncing / repairing a stripe
171 * @check_state_idle - check operations are quiesced
172 * @check_state_run - check operation is running
173 * @check_state_result - set outside lock when check result is valid
174 * @check_state_compute_run - check failed and we are repairing
175 * @check_state_compute_result - set outside lock when compute result is valid
176 */
177enum check_states {
178 check_state_idle = 0,
179 check_state_run, /* parity check */
180 check_state_check_result,
181 check_state_compute_run, /* parity repair */
182 check_state_compute_result,
183};
184
185/**
186 * enum reconstruct_states - handles writing or expanding a stripe
187 */
188enum reconstruct_states {
189 reconstruct_state_idle = 0,
190 reconstruct_state_prexor_drain_run, /* prexor-write */
191 reconstruct_state_drain_run, /* write */
192 reconstruct_state_run, /* expand */
193 reconstruct_state_prexor_drain_result,
194 reconstruct_state_drain_result,
195 reconstruct_state_result,
196};
197
198struct stripe_head {
199 struct hlist_node hash;
200 struct list_head lru; /* inactive_list or handle_list */
201 struct raid5_private_data *raid_conf;
202 sector_t sector; /* sector of this row */
203 int pd_idx; /* parity disk index */
204 unsigned long state; /* state flags */
205 atomic_t count; /* nr of active thread/requests */
206 spinlock_t lock;
207 int bm_seq; /* sequence number for bitmap flushes */
208 int disks; /* disks in stripe */
209 enum check_states check_state;
210 enum reconstruct_states reconstruct_state;
211 /* stripe_operations
212 * @target - STRIPE_OP_COMPUTE_BLK target
213 */
214 struct stripe_operations {
215 int target;
216 u32 zero_sum_result;
217 } ops;
218 struct r5dev {
219 struct bio req;
220 struct bio_vec vec;
221 struct page *page;
222 struct bio *toread, *read, *towrite, *written;
223 sector_t sector; /* sector of this page */
224 unsigned long flags;
225 } dev[1]; /* allocated with extra space depending of RAID geometry */
226};
227
228/* stripe_head_state - collects and tracks the dynamic state of a stripe_head
229 * for handle_stripe. It is only valid under spin_lock(sh->lock);
230 */
231struct stripe_head_state {
232 int syncing, expanding, expanded;
233 int locked, uptodate, to_read, to_write, failed, written;
234 int to_fill, compute, req_compute, non_overwrite;
235 int failed_num;
236 unsigned long ops_request;
237};
238
239/* r6_state - extra state data only relevant to r6 */
240struct r6_state {
241 int p_failed, q_failed, qd_idx, failed_num[2];
242};
243
244/* Flags */
245#define R5_UPTODATE 0 /* page contains current data */
246#define R5_LOCKED 1 /* IO has been submitted on "req" */
247#define R5_OVERWRITE 2 /* towrite covers whole page */
248/* and some that are internal to handle_stripe */
249#define R5_Insync 3 /* rdev && rdev->in_sync at start */
250#define R5_Wantread 4 /* want to schedule a read */
251#define R5_Wantwrite 5
252#define R5_Overlap 7 /* There is a pending overlapping request on this block */
253#define R5_ReadError 8 /* seen a read error here recently */
254#define R5_ReWrite 9 /* have tried to over-write the readerror */
255
256#define R5_Expanded 10 /* This block now has post-expand data */
257#define R5_Wantcompute 11 /* compute_block in progress treat as
258 * uptodate
259 */
260#define R5_Wantfill 12 /* dev->toread contains a bio that needs
261 * filling
262 */
263#define R5_Wantdrain 13 /* dev->towrite needs to be drained */
264/*
265 * Write method
266 */
267#define RECONSTRUCT_WRITE 1
268#define READ_MODIFY_WRITE 2
269/* not a write method, but a compute_parity mode */
270#define CHECK_PARITY 3
271
272/*
273 * Stripe state
274 */
275#define STRIPE_HANDLE 2
276#define STRIPE_SYNCING 3
277#define STRIPE_INSYNC 4
278#define STRIPE_PREREAD_ACTIVE 5
279#define STRIPE_DELAYED 6
280#define STRIPE_DEGRADED 7
281#define STRIPE_BIT_DELAY 8
282#define STRIPE_EXPANDING 9
283#define STRIPE_EXPAND_SOURCE 10
284#define STRIPE_EXPAND_READY 11
285#define STRIPE_IO_STARTED 12 /* do not count towards 'bypass_count' */
286#define STRIPE_FULL_WRITE 13 /* all blocks are set to be overwritten */
287#define STRIPE_BIOFILL_RUN 14
288#define STRIPE_COMPUTE_RUN 15
289/*
290 * Operation request flags
291 */
292#define STRIPE_OP_BIOFILL 0
293#define STRIPE_OP_COMPUTE_BLK 1
294#define STRIPE_OP_PREXOR 2
295#define STRIPE_OP_BIODRAIN 3
296#define STRIPE_OP_POSTXOR 4
297#define STRIPE_OP_CHECK 5
298
299/*
300 * Plugging:
301 *
302 * To improve write throughput, we need to delay the handling of some
303 * stripes until there has been a chance that several write requests
304 * for the one stripe have all been collected.
305 * In particular, any write request that would require pre-reading
306 * is put on a "delayed" queue until there are no stripes currently
307 * in a pre-read phase. Further, if the "delayed" queue is empty when
308 * a stripe is put on it then we "plug" the queue and do not process it
309 * until an unplug call is made. (the unplug_io_fn() is called).
310 *
311 * When preread is initiated on a stripe, we set PREREAD_ACTIVE and add
312 * it to the count of prereading stripes.
313 * When write is initiated, or the stripe refcnt == 0 (just in case) we
314 * clear the PREREAD_ACTIVE flag and decrement the count
315 * Whenever the 'handle' queue is empty and the device is not plugged, we
316 * move any strips from delayed to handle and clear the DELAYED flag and set
317 * PREREAD_ACTIVE.
318 * In stripe_handle, if we find pre-reading is necessary, we do it if
319 * PREREAD_ACTIVE is set, else we set DELAYED which will send it to the delayed queue.
320 * HANDLE gets cleared if stripe_handle leave nothing locked.
321 */
322
323
324struct disk_info {
325 mdk_rdev_t *rdev;
326};
327
328struct raid5_private_data {
329 struct hlist_head *stripe_hashtbl;
330 mddev_t *mddev;
331 struct disk_info *spare;
332 int chunk_size, level, algorithm;
333 int max_degraded;
334 int raid_disks;
335 int max_nr_stripes;
336
337 /* used during an expand */
338 sector_t expand_progress; /* MaxSector when no expand happening */
339 sector_t expand_lo; /* from here up to expand_progress it out-of-bounds
340 * as we haven't flushed the metadata yet
341 */
342 int previous_raid_disks;
343
344 struct list_head handle_list; /* stripes needing handling */
345 struct list_head hold_list; /* preread ready stripes */
346 struct list_head delayed_list; /* stripes that have plugged requests */
347 struct list_head bitmap_list; /* stripes delaying awaiting bitmap update */
348 struct bio *retry_read_aligned; /* currently retrying aligned bios */
349 struct bio *retry_read_aligned_list; /* aligned bios retry list */
350 atomic_t preread_active_stripes; /* stripes with scheduled io */
351 atomic_t active_aligned_reads;
352 atomic_t pending_full_writes; /* full write backlog */
353 int bypass_count; /* bypassed prereads */
354 int bypass_threshold; /* preread nice */
355 struct list_head *last_hold; /* detect hold_list promotions */
356
357 atomic_t reshape_stripes; /* stripes with pending writes for reshape */
358 /* unfortunately we need two cache names as we temporarily have
359 * two caches.
360 */
361 int active_name;
362 char cache_name[2][20];
363 struct kmem_cache *slab_cache; /* for allocating stripes */
364
365 int seq_flush, seq_write;
366 int quiesce;
367
368 int fullsync; /* set to 1 if a full sync is needed,
369 * (fresh device added).
370 * Cleared when a sync completes.
371 */
372
373 struct page *spare_page; /* Used when checking P/Q in raid6 */
374
375 /*
376 * Free stripes pool
377 */
378 atomic_t active_stripes;
379 struct list_head inactive_list;
380 wait_queue_head_t wait_for_stripe;
381 wait_queue_head_t wait_for_overlap;
382 int inactive_blocked; /* release of inactive stripes blocked,
383 * waiting for 25% to be free
384 */
385 int pool_size; /* number of disks in stripeheads in pool */
386 spinlock_t device_lock;
387 struct disk_info *disks;
388};
389
390typedef struct raid5_private_data raid5_conf_t;
391
392#define mddev_to_conf(mddev) ((raid5_conf_t *) mddev->private)
393
394/*
395 * Our supported algorithms
396 */
397#define ALGORITHM_LEFT_ASYMMETRIC 0
398#define ALGORITHM_RIGHT_ASYMMETRIC 1
399#define ALGORITHM_LEFT_SYMMETRIC 2
400#define ALGORITHM_RIGHT_SYMMETRIC 3
401
402#endif
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