2 * bitmap.c two-level bitmap (C) Peter T. Breuer (ptb@ot.uc3m.es) 2003
4 * bitmap_create - sets up the bitmap structure
5 * bitmap_destroy - destroys the bitmap structure
7 * additions, Copyright (C) 2003-2004, Paul Clements, SteelEye Technology, Inc.:
8 * - added disk storage for bitmap
9 * - changes to allow various bitmap chunk sizes
15 * flush after percent set rather than just time based. (maybe both).
18 #include <linux/blkdev.h>
19 #include <linux/module.h>
20 #include <linux/errno.h>
21 #include <linux/slab.h>
22 #include <linux/init.h>
23 #include <linux/timer.h>
24 #include <linux/sched.h>
25 #include <linux/list.h>
26 #include <linux/file.h>
27 #include <linux/mount.h>
28 #include <linux/buffer_head.h>
29 #include <linux/seq_file.h>
33 static inline char *bmname(struct bitmap
*bitmap
)
35 return bitmap
->mddev
? mdname(bitmap
->mddev
) : "mdX";
39 * check a page and, if necessary, allocate it (or hijack it if the alloc fails)
41 * 1) check to see if this page is allocated, if it's not then try to alloc
42 * 2) if the alloc fails, set the page's hijacked flag so we'll use the
43 * page pointer directly as a counter
45 * if we find our page, we increment the page's refcount so that it stays
46 * allocated while we're using it
48 static int bitmap_checkpage(struct bitmap_counts
*bitmap
,
49 unsigned long page
, int create
)
50 __releases(bitmap
->lock
)
51 __acquires(bitmap
->lock
)
53 unsigned char *mappage
;
55 if (page
>= bitmap
->pages
) {
56 /* This can happen if bitmap_start_sync goes beyond
57 * End-of-device while looking for a whole page.
63 if (bitmap
->bp
[page
].hijacked
) /* it's hijacked, don't try to alloc */
66 if (bitmap
->bp
[page
].map
) /* page is already allocated, just return */
72 /* this page has not been allocated yet */
74 spin_unlock_irq(&bitmap
->lock
);
75 mappage
= kzalloc(PAGE_SIZE
, GFP_NOIO
);
76 spin_lock_irq(&bitmap
->lock
);
78 if (mappage
== NULL
) {
79 pr_debug("md/bitmap: map page allocation failed, hijacking\n");
80 /* failed - set the hijacked flag so that we can use the
81 * pointer as a counter */
82 if (!bitmap
->bp
[page
].map
)
83 bitmap
->bp
[page
].hijacked
= 1;
84 } else if (bitmap
->bp
[page
].map
||
85 bitmap
->bp
[page
].hijacked
) {
86 /* somebody beat us to getting the page */
91 /* no page was in place and we have one, so install it */
93 bitmap
->bp
[page
].map
= mappage
;
94 bitmap
->missing_pages
--;
99 /* if page is completely empty, put it back on the free list, or dealloc it */
100 /* if page was hijacked, unmark the flag so it might get alloced next time */
101 /* Note: lock should be held when calling this */
102 static void bitmap_checkfree(struct bitmap_counts
*bitmap
, unsigned long page
)
106 if (bitmap
->bp
[page
].count
) /* page is still busy */
109 /* page is no longer in use, it can be released */
111 if (bitmap
->bp
[page
].hijacked
) { /* page was hijacked, undo this now */
112 bitmap
->bp
[page
].hijacked
= 0;
113 bitmap
->bp
[page
].map
= NULL
;
115 /* normal case, free the page */
116 ptr
= bitmap
->bp
[page
].map
;
117 bitmap
->bp
[page
].map
= NULL
;
118 bitmap
->missing_pages
++;
124 * bitmap file handling - read and write the bitmap file and its superblock
128 * basic page I/O operations
131 /* IO operations when bitmap is stored near all superblocks */
132 static int read_sb_page(struct mddev
*mddev
, loff_t offset
,
134 unsigned long index
, int size
)
136 /* choose a good rdev and read the page from there */
138 struct md_rdev
*rdev
;
141 rdev_for_each(rdev
, mddev
) {
142 if (! test_bit(In_sync
, &rdev
->flags
)
143 || test_bit(Faulty
, &rdev
->flags
))
146 target
= offset
+ index
* (PAGE_SIZE
/512);
148 if (sync_page_io(rdev
, target
,
149 roundup(size
, bdev_logical_block_size(rdev
->bdev
)),
158 static struct md_rdev
*next_active_rdev(struct md_rdev
*rdev
, struct mddev
*mddev
)
160 /* Iterate the disks of an mddev, using rcu to protect access to the
161 * linked list, and raising the refcount of devices we return to ensure
162 * they don't disappear while in use.
163 * As devices are only added or removed when raid_disk is < 0 and
164 * nr_pending is 0 and In_sync is clear, the entries we return will
165 * still be in the same position on the list when we re-enter
166 * list_for_each_continue_rcu.
168 struct list_head
*pos
;
171 /* start at the beginning */
174 /* release the previous rdev and start from there. */
175 rdev_dec_pending(rdev
, mddev
);
176 pos
= &rdev
->same_set
;
178 list_for_each_continue_rcu(pos
, &mddev
->disks
) {
179 rdev
= list_entry(pos
, struct md_rdev
, same_set
);
180 if (rdev
->raid_disk
>= 0 &&
181 !test_bit(Faulty
, &rdev
->flags
)) {
182 /* this is a usable devices */
183 atomic_inc(&rdev
->nr_pending
);
192 static int write_sb_page(struct bitmap
*bitmap
, struct page
*page
, int wait
)
194 struct md_rdev
*rdev
= NULL
;
195 struct block_device
*bdev
;
196 struct mddev
*mddev
= bitmap
->mddev
;
197 struct bitmap_storage
*store
= &bitmap
->storage
;
199 while ((rdev
= next_active_rdev(rdev
, mddev
)) != NULL
) {
200 int size
= PAGE_SIZE
;
201 loff_t offset
= mddev
->bitmap_info
.offset
;
203 bdev
= (rdev
->meta_bdev
) ? rdev
->meta_bdev
: rdev
->bdev
;
205 if (page
->index
== store
->file_pages
-1) {
206 int last_page_size
= store
->bytes
& (PAGE_SIZE
-1);
207 if (last_page_size
== 0)
208 last_page_size
= PAGE_SIZE
;
209 size
= roundup(last_page_size
,
210 bdev_logical_block_size(bdev
));
212 /* Just make sure we aren't corrupting data or
215 if (mddev
->external
) {
216 /* Bitmap could be anywhere. */
217 if (rdev
->sb_start
+ offset
+ (page
->index
221 rdev
->sb_start
+ offset
222 < (rdev
->data_offset
+ mddev
->dev_sectors
225 } else if (offset
< 0) {
226 /* DATA BITMAP METADATA */
228 + (long)(page
->index
* (PAGE_SIZE
/512))
230 /* bitmap runs in to metadata */
232 if (rdev
->data_offset
+ mddev
->dev_sectors
233 > rdev
->sb_start
+ offset
)
234 /* data runs in to bitmap */
236 } else if (rdev
->sb_start
< rdev
->data_offset
) {
237 /* METADATA BITMAP DATA */
240 + page
->index
*(PAGE_SIZE
/512) + size
/512
242 /* bitmap runs in to data */
245 /* DATA METADATA BITMAP - no problems */
247 md_super_write(mddev
, rdev
,
248 rdev
->sb_start
+ offset
249 + page
->index
* (PAGE_SIZE
/512),
255 md_super_wait(mddev
);
262 static void bitmap_file_kick(struct bitmap
*bitmap
);
264 * write out a page to a file
266 static void write_page(struct bitmap
*bitmap
, struct page
*page
, int wait
)
268 struct buffer_head
*bh
;
270 if (bitmap
->storage
.file
== NULL
) {
271 switch (write_sb_page(bitmap
, page
, wait
)) {
273 set_bit(BITMAP_WRITE_ERROR
, &bitmap
->flags
);
277 bh
= page_buffers(page
);
279 while (bh
&& bh
->b_blocknr
) {
280 atomic_inc(&bitmap
->pending_writes
);
281 set_buffer_locked(bh
);
282 set_buffer_mapped(bh
);
283 submit_bh(WRITE
| REQ_SYNC
, bh
);
284 bh
= bh
->b_this_page
;
288 wait_event(bitmap
->write_wait
,
289 atomic_read(&bitmap
->pending_writes
)==0);
291 if (test_bit(BITMAP_WRITE_ERROR
, &bitmap
->flags
))
292 bitmap_file_kick(bitmap
);
295 static void end_bitmap_write(struct buffer_head
*bh
, int uptodate
)
297 struct bitmap
*bitmap
= bh
->b_private
;
300 set_bit(BITMAP_WRITE_ERROR
, &bitmap
->flags
);
301 if (atomic_dec_and_test(&bitmap
->pending_writes
))
302 wake_up(&bitmap
->write_wait
);
305 /* copied from buffer.c */
307 __clear_page_buffers(struct page
*page
)
309 ClearPagePrivate(page
);
310 set_page_private(page
, 0);
311 page_cache_release(page
);
313 static void free_buffers(struct page
*page
)
315 struct buffer_head
*bh
;
317 if (!PagePrivate(page
))
320 bh
= page_buffers(page
);
322 struct buffer_head
*next
= bh
->b_this_page
;
323 free_buffer_head(bh
);
326 __clear_page_buffers(page
);
330 /* read a page from a file.
331 * We both read the page, and attach buffers to the page to record the
332 * address of each block (using bmap). These addresses will be used
333 * to write the block later, completely bypassing the filesystem.
334 * This usage is similar to how swap files are handled, and allows us
335 * to write to a file with no concerns of memory allocation failing.
337 static int read_page(struct file
*file
, unsigned long index
,
338 struct bitmap
*bitmap
,
343 struct inode
*inode
= file
->f_path
.dentry
->d_inode
;
344 struct buffer_head
*bh
;
347 pr_debug("read bitmap file (%dB @ %llu)\n", (int)PAGE_SIZE
,
348 (unsigned long long)index
<< PAGE_SHIFT
);
350 bh
= alloc_page_buffers(page
, 1<<inode
->i_blkbits
, 0);
355 attach_page_buffers(page
, bh
);
356 block
= index
<< (PAGE_SHIFT
- inode
->i_blkbits
);
361 bh
->b_blocknr
= bmap(inode
, block
);
362 if (bh
->b_blocknr
== 0) {
363 /* Cannot use this file! */
367 bh
->b_bdev
= inode
->i_sb
->s_bdev
;
368 if (count
< (1<<inode
->i_blkbits
))
371 count
-= (1<<inode
->i_blkbits
);
373 bh
->b_end_io
= end_bitmap_write
;
374 bh
->b_private
= bitmap
;
375 atomic_inc(&bitmap
->pending_writes
);
376 set_buffer_locked(bh
);
377 set_buffer_mapped(bh
);
381 bh
= bh
->b_this_page
;
385 wait_event(bitmap
->write_wait
,
386 atomic_read(&bitmap
->pending_writes
)==0);
387 if (test_bit(BITMAP_WRITE_ERROR
, &bitmap
->flags
))
391 printk(KERN_ALERT
"md: bitmap read error: (%dB @ %llu): %d\n",
393 (unsigned long long)index
<< PAGE_SHIFT
,
399 * bitmap file superblock operations
402 /* update the event counter and sync the superblock to disk */
403 void bitmap_update_sb(struct bitmap
*bitmap
)
407 if (!bitmap
|| !bitmap
->mddev
) /* no bitmap for this array */
409 if (bitmap
->mddev
->bitmap_info
.external
)
411 if (!bitmap
->storage
.sb_page
) /* no superblock */
413 sb
= kmap_atomic(bitmap
->storage
.sb_page
);
414 sb
->events
= cpu_to_le64(bitmap
->mddev
->events
);
415 if (bitmap
->mddev
->events
< bitmap
->events_cleared
)
416 /* rocking back to read-only */
417 bitmap
->events_cleared
= bitmap
->mddev
->events
;
418 sb
->events_cleared
= cpu_to_le64(bitmap
->events_cleared
);
419 sb
->state
= cpu_to_le32(bitmap
->flags
);
420 /* Just in case these have been changed via sysfs: */
421 sb
->daemon_sleep
= cpu_to_le32(bitmap
->mddev
->bitmap_info
.daemon_sleep
/HZ
);
422 sb
->write_behind
= cpu_to_le32(bitmap
->mddev
->bitmap_info
.max_write_behind
);
424 write_page(bitmap
, bitmap
->storage
.sb_page
, 1);
427 /* print out the bitmap file superblock */
428 void bitmap_print_sb(struct bitmap
*bitmap
)
432 if (!bitmap
|| !bitmap
->storage
.sb_page
)
434 sb
= kmap_atomic(bitmap
->storage
.sb_page
);
435 printk(KERN_DEBUG
"%s: bitmap file superblock:\n", bmname(bitmap
));
436 printk(KERN_DEBUG
" magic: %08x\n", le32_to_cpu(sb
->magic
));
437 printk(KERN_DEBUG
" version: %d\n", le32_to_cpu(sb
->version
));
438 printk(KERN_DEBUG
" uuid: %08x.%08x.%08x.%08x\n",
439 *(__u32
*)(sb
->uuid
+0),
440 *(__u32
*)(sb
->uuid
+4),
441 *(__u32
*)(sb
->uuid
+8),
442 *(__u32
*)(sb
->uuid
+12));
443 printk(KERN_DEBUG
" events: %llu\n",
444 (unsigned long long) le64_to_cpu(sb
->events
));
445 printk(KERN_DEBUG
"events cleared: %llu\n",
446 (unsigned long long) le64_to_cpu(sb
->events_cleared
));
447 printk(KERN_DEBUG
" state: %08x\n", le32_to_cpu(sb
->state
));
448 printk(KERN_DEBUG
" chunksize: %d B\n", le32_to_cpu(sb
->chunksize
));
449 printk(KERN_DEBUG
" daemon sleep: %ds\n", le32_to_cpu(sb
->daemon_sleep
));
450 printk(KERN_DEBUG
" sync size: %llu KB\n",
451 (unsigned long long)le64_to_cpu(sb
->sync_size
)/2);
452 printk(KERN_DEBUG
"max write behind: %d\n", le32_to_cpu(sb
->write_behind
));
460 * This function is somewhat the reverse of bitmap_read_sb. bitmap_read_sb
461 * reads and verifies the on-disk bitmap superblock and populates bitmap_info.
462 * This function verifies 'bitmap_info' and populates the on-disk bitmap
463 * structure, which is to be written to disk.
465 * Returns: 0 on success, -Exxx on error
467 static int bitmap_new_disk_sb(struct bitmap
*bitmap
)
470 unsigned long chunksize
, daemon_sleep
, write_behind
;
473 bitmap
->storage
.sb_page
= alloc_page(GFP_KERNEL
);
474 if (IS_ERR(bitmap
->storage
.sb_page
)) {
475 err
= PTR_ERR(bitmap
->storage
.sb_page
);
476 bitmap
->storage
.sb_page
= NULL
;
479 bitmap
->storage
.sb_page
->index
= 0;
481 sb
= kmap_atomic(bitmap
->storage
.sb_page
);
483 sb
->magic
= cpu_to_le32(BITMAP_MAGIC
);
484 sb
->version
= cpu_to_le32(BITMAP_MAJOR_HI
);
486 chunksize
= bitmap
->mddev
->bitmap_info
.chunksize
;
488 if (!is_power_of_2(chunksize
)) {
490 printk(KERN_ERR
"bitmap chunksize not a power of 2\n");
493 sb
->chunksize
= cpu_to_le32(chunksize
);
495 daemon_sleep
= bitmap
->mddev
->bitmap_info
.daemon_sleep
;
497 (daemon_sleep
< 1) || (daemon_sleep
> MAX_SCHEDULE_TIMEOUT
)) {
498 printk(KERN_INFO
"Choosing daemon_sleep default (5 sec)\n");
499 daemon_sleep
= 5 * HZ
;
501 sb
->daemon_sleep
= cpu_to_le32(daemon_sleep
);
502 bitmap
->mddev
->bitmap_info
.daemon_sleep
= daemon_sleep
;
505 * FIXME: write_behind for RAID1. If not specified, what
506 * is a good choice? We choose COUNTER_MAX / 2 arbitrarily.
508 write_behind
= bitmap
->mddev
->bitmap_info
.max_write_behind
;
509 if (write_behind
> COUNTER_MAX
)
510 write_behind
= COUNTER_MAX
/ 2;
511 sb
->write_behind
= cpu_to_le32(write_behind
);
512 bitmap
->mddev
->bitmap_info
.max_write_behind
= write_behind
;
514 /* keep the array size field of the bitmap superblock up to date */
515 sb
->sync_size
= cpu_to_le64(bitmap
->mddev
->resync_max_sectors
);
517 memcpy(sb
->uuid
, bitmap
->mddev
->uuid
, 16);
519 set_bit(BITMAP_STALE
, &bitmap
->flags
);
520 sb
->state
= cpu_to_le32(bitmap
->flags
);
521 bitmap
->events_cleared
= bitmap
->mddev
->events
;
522 sb
->events_cleared
= cpu_to_le64(bitmap
->mddev
->events
);
529 /* read the superblock from the bitmap file and initialize some bitmap fields */
530 static int bitmap_read_sb(struct bitmap
*bitmap
)
534 unsigned long chunksize
, daemon_sleep
, write_behind
;
535 unsigned long long events
;
537 struct page
*sb_page
;
539 if (!bitmap
->storage
.file
&& !bitmap
->mddev
->bitmap_info
.offset
) {
540 chunksize
= 128 * 1024 * 1024;
541 daemon_sleep
= 5 * HZ
;
543 set_bit(BITMAP_STALE
, &bitmap
->flags
);
547 /* page 0 is the superblock, read it... */
548 sb_page
= alloc_page(GFP_KERNEL
);
551 bitmap
->storage
.sb_page
= sb_page
;
553 if (bitmap
->storage
.file
) {
554 loff_t isize
= i_size_read(bitmap
->storage
.file
->f_mapping
->host
);
555 int bytes
= isize
> PAGE_SIZE
? PAGE_SIZE
: isize
;
557 err
= read_page(bitmap
->storage
.file
, 0,
558 bitmap
, bytes
, sb_page
);
560 err
= read_sb_page(bitmap
->mddev
,
561 bitmap
->mddev
->bitmap_info
.offset
,
563 0, sizeof(bitmap_super_t
));
568 sb
= kmap_atomic(sb_page
);
570 chunksize
= le32_to_cpu(sb
->chunksize
);
571 daemon_sleep
= le32_to_cpu(sb
->daemon_sleep
) * HZ
;
572 write_behind
= le32_to_cpu(sb
->write_behind
);
574 /* verify that the bitmap-specific fields are valid */
575 if (sb
->magic
!= cpu_to_le32(BITMAP_MAGIC
))
576 reason
= "bad magic";
577 else if (le32_to_cpu(sb
->version
) < BITMAP_MAJOR_LO
||
578 le32_to_cpu(sb
->version
) > BITMAP_MAJOR_HI
)
579 reason
= "unrecognized superblock version";
580 else if (chunksize
< 512)
581 reason
= "bitmap chunksize too small";
582 else if (!is_power_of_2(chunksize
))
583 reason
= "bitmap chunksize not a power of 2";
584 else if (daemon_sleep
< 1 || daemon_sleep
> MAX_SCHEDULE_TIMEOUT
)
585 reason
= "daemon sleep period out of range";
586 else if (write_behind
> COUNTER_MAX
)
587 reason
= "write-behind limit out of range (0 - 16383)";
589 printk(KERN_INFO
"%s: invalid bitmap file superblock: %s\n",
590 bmname(bitmap
), reason
);
594 /* keep the array size field of the bitmap superblock up to date */
595 sb
->sync_size
= cpu_to_le64(bitmap
->mddev
->resync_max_sectors
);
597 if (bitmap
->mddev
->persistent
) {
599 * We have a persistent array superblock, so compare the
600 * bitmap's UUID and event counter to the mddev's
602 if (memcmp(sb
->uuid
, bitmap
->mddev
->uuid
, 16)) {
604 "%s: bitmap superblock UUID mismatch\n",
608 events
= le64_to_cpu(sb
->events
);
609 if (events
< bitmap
->mddev
->events
) {
611 "%s: bitmap file is out of date (%llu < %llu) "
612 "-- forcing full recovery\n",
613 bmname(bitmap
), events
,
614 (unsigned long long) bitmap
->mddev
->events
);
615 set_bit(BITMAP_STALE
, &bitmap
->flags
);
619 /* assign fields using values from superblock */
620 bitmap
->flags
|= le32_to_cpu(sb
->state
);
621 if (le32_to_cpu(sb
->version
) == BITMAP_MAJOR_HOSTENDIAN
)
622 set_bit(BITMAP_HOSTENDIAN
, &bitmap
->flags
);
623 bitmap
->events_cleared
= le64_to_cpu(sb
->events_cleared
);
628 if (test_bit(BITMAP_STALE
, &bitmap
->flags
))
629 bitmap
->events_cleared
= bitmap
->mddev
->events
;
630 bitmap
->mddev
->bitmap_info
.chunksize
= chunksize
;
631 bitmap
->mddev
->bitmap_info
.daemon_sleep
= daemon_sleep
;
632 bitmap
->mddev
->bitmap_info
.max_write_behind
= write_behind
;
634 bitmap_print_sb(bitmap
);
639 * general bitmap file operations
645 * Use one bit per "chunk" (block set). We do the disk I/O on the bitmap
646 * file a page at a time. There's a superblock at the start of the file.
648 /* calculate the index of the page that contains this bit */
649 static inline unsigned long file_page_index(struct bitmap_storage
*store
,
653 chunk
+= sizeof(bitmap_super_t
) << 3;
654 return chunk
>> PAGE_BIT_SHIFT
;
657 /* calculate the (bit) offset of this bit within a page */
658 static inline unsigned long file_page_offset(struct bitmap_storage
*store
,
662 chunk
+= sizeof(bitmap_super_t
) << 3;
663 return chunk
& (PAGE_BITS
- 1);
667 * return a pointer to the page in the filemap that contains the given bit
669 * this lookup is complicated by the fact that the bitmap sb might be exactly
670 * 1 page (e.g., x86) or less than 1 page -- so the bitmap might start on page
673 static inline struct page
*filemap_get_page(struct bitmap_storage
*store
,
676 if (file_page_index(store
, chunk
) >= store
->file_pages
)
678 return store
->filemap
[file_page_index(store
, chunk
)
679 - file_page_index(store
, 0)];
682 static int bitmap_storage_alloc(struct bitmap_storage
*store
,
683 unsigned long chunks
, int with_super
)
686 unsigned long num_pages
;
689 bytes
= DIV_ROUND_UP(chunks
, 8);
691 bytes
+= sizeof(bitmap_super_t
);
693 num_pages
= DIV_ROUND_UP(bytes
, PAGE_SIZE
);
695 store
->filemap
= kmalloc(sizeof(struct page
*)
696 * num_pages
, GFP_KERNEL
);
700 if (with_super
&& !store
->sb_page
) {
701 store
->sb_page
= alloc_page(GFP_KERNEL
);
702 if (store
->sb_page
== NULL
)
704 store
->sb_page
->index
= 0;
707 if (store
->sb_page
) {
708 store
->filemap
[0] = store
->sb_page
;
711 for ( ; pnum
< num_pages
; pnum
++) {
712 store
->filemap
[pnum
] = alloc_page(GFP_KERNEL
);
713 if (!store
->filemap
[pnum
]) {
714 store
->file_pages
= pnum
;
717 store
->filemap
[pnum
]->index
= pnum
;
719 store
->file_pages
= pnum
;
721 /* We need 4 bits per page, rounded up to a multiple
722 * of sizeof(unsigned long) */
723 store
->filemap_attr
= kzalloc(
724 roundup(DIV_ROUND_UP(num_pages
*4, 8), sizeof(unsigned long)),
726 if (!store
->filemap_attr
)
729 store
->bytes
= bytes
;
734 static void bitmap_file_unmap(struct bitmap_storage
*store
)
736 struct page
**map
, *sb_page
;
741 map
= store
->filemap
;
742 pages
= store
->file_pages
;
743 sb_page
= store
->sb_page
;
746 if (map
[pages
] != sb_page
) /* 0 is sb_page, release it below */
747 free_buffers(map
[pages
]);
749 kfree(store
->filemap_attr
);
752 free_buffers(sb_page
);
755 struct inode
*inode
= file
->f_path
.dentry
->d_inode
;
756 invalidate_mapping_pages(inode
->i_mapping
, 0, -1);
762 * bitmap_file_kick - if an error occurs while manipulating the bitmap file
763 * then it is no longer reliable, so we stop using it and we mark the file
764 * as failed in the superblock
766 static void bitmap_file_kick(struct bitmap
*bitmap
)
768 char *path
, *ptr
= NULL
;
770 if (!test_and_set_bit(BITMAP_STALE
, &bitmap
->flags
)) {
771 bitmap_update_sb(bitmap
);
773 if (bitmap
->storage
.file
) {
774 path
= kmalloc(PAGE_SIZE
, GFP_KERNEL
);
776 ptr
= d_path(&bitmap
->storage
.file
->f_path
,
780 "%s: kicking failed bitmap file %s from array!\n",
781 bmname(bitmap
), IS_ERR(ptr
) ? "" : ptr
);
786 "%s: disabling internal bitmap due to errors\n",
791 enum bitmap_page_attr
{
792 BITMAP_PAGE_DIRTY
= 0, /* there are set bits that need to be synced */
793 BITMAP_PAGE_PENDING
= 1, /* there are bits that are being cleaned.
794 * i.e. counter is 1 or 2. */
795 BITMAP_PAGE_NEEDWRITE
= 2, /* there are cleared bits that need to be synced */
798 static inline void set_page_attr(struct bitmap
*bitmap
, int pnum
,
799 enum bitmap_page_attr attr
)
801 set_bit((pnum
<<2) + attr
, bitmap
->storage
.filemap_attr
);
804 static inline void clear_page_attr(struct bitmap
*bitmap
, int pnum
,
805 enum bitmap_page_attr attr
)
807 clear_bit((pnum
<<2) + attr
, bitmap
->storage
.filemap_attr
);
810 static inline int test_page_attr(struct bitmap
*bitmap
, int pnum
,
811 enum bitmap_page_attr attr
)
813 return test_bit((pnum
<<2) + attr
, bitmap
->storage
.filemap_attr
);
816 static inline int test_and_clear_page_attr(struct bitmap
*bitmap
, int pnum
,
817 enum bitmap_page_attr attr
)
819 return test_and_clear_bit((pnum
<<2) + attr
,
820 bitmap
->storage
.filemap_attr
);
823 * bitmap_file_set_bit -- called before performing a write to the md device
824 * to set (and eventually sync) a particular bit in the bitmap file
826 * we set the bit immediately, then we record the page number so that
827 * when an unplug occurs, we can flush the dirty pages out to disk
829 static void bitmap_file_set_bit(struct bitmap
*bitmap
, sector_t block
)
834 unsigned long chunk
= block
>> bitmap
->counts
.chunkshift
;
836 page
= filemap_get_page(&bitmap
->storage
, chunk
);
839 bit
= file_page_offset(&bitmap
->storage
, chunk
);
842 kaddr
= kmap_atomic(page
);
843 if (test_bit(BITMAP_HOSTENDIAN
, &bitmap
->flags
))
846 test_and_set_bit_le(bit
, kaddr
);
847 kunmap_atomic(kaddr
);
848 pr_debug("set file bit %lu page %lu\n", bit
, page
->index
);
849 /* record page number so it gets flushed to disk when unplug occurs */
850 set_page_attr(bitmap
, page
->index
, BITMAP_PAGE_DIRTY
);
853 static void bitmap_file_clear_bit(struct bitmap
*bitmap
, sector_t block
)
858 unsigned long chunk
= block
>> bitmap
->counts
.chunkshift
;
860 page
= filemap_get_page(&bitmap
->storage
, chunk
);
863 bit
= file_page_offset(&bitmap
->storage
, chunk
);
864 paddr
= kmap_atomic(page
);
865 if (test_bit(BITMAP_HOSTENDIAN
, &bitmap
->flags
))
866 clear_bit(bit
, paddr
);
868 test_and_clear_bit_le(bit
, paddr
);
869 kunmap_atomic(paddr
);
870 if (!test_page_attr(bitmap
, page
->index
, BITMAP_PAGE_NEEDWRITE
)) {
871 set_page_attr(bitmap
, page
->index
, BITMAP_PAGE_PENDING
);
872 bitmap
->allclean
= 0;
876 /* this gets called when the md device is ready to unplug its underlying
877 * (slave) device queues -- before we let any writes go down, we need to
878 * sync the dirty pages of the bitmap file to disk */
879 void bitmap_unplug(struct bitmap
*bitmap
)
882 int dirty
, need_write
;
885 if (!bitmap
|| !bitmap
->storage
.filemap
||
886 test_bit(BITMAP_STALE
, &bitmap
->flags
))
889 /* look at each page to see if there are any set bits that need to be
890 * flushed out to disk */
891 for (i
= 0; i
< bitmap
->storage
.file_pages
; i
++) {
892 if (!bitmap
->storage
.filemap
)
894 dirty
= test_and_clear_page_attr(bitmap
, i
, BITMAP_PAGE_DIRTY
);
895 need_write
= test_and_clear_page_attr(bitmap
, i
,
896 BITMAP_PAGE_NEEDWRITE
);
897 if (dirty
|| need_write
) {
898 clear_page_attr(bitmap
, i
, BITMAP_PAGE_PENDING
);
899 write_page(bitmap
, bitmap
->storage
.filemap
[i
], 0);
904 if (wait
) { /* if any writes were performed, we need to wait on them */
905 if (bitmap
->storage
.file
)
906 wait_event(bitmap
->write_wait
,
907 atomic_read(&bitmap
->pending_writes
)==0);
909 md_super_wait(bitmap
->mddev
);
911 if (test_bit(BITMAP_WRITE_ERROR
, &bitmap
->flags
))
912 bitmap_file_kick(bitmap
);
914 EXPORT_SYMBOL(bitmap_unplug
);
916 static void bitmap_set_memory_bits(struct bitmap
*bitmap
, sector_t offset
, int needed
);
917 /* * bitmap_init_from_disk -- called at bitmap_create time to initialize
918 * the in-memory bitmap from the on-disk bitmap -- also, sets up the
919 * memory mapping of the bitmap file
921 * if there's no bitmap file, or if the bitmap file had been
922 * previously kicked from the array, we mark all the bits as
923 * 1's in order to cause a full resync.
925 * We ignore all bits for sectors that end earlier than 'start'.
926 * This is used when reading an out-of-date bitmap...
928 static int bitmap_init_from_disk(struct bitmap
*bitmap
, sector_t start
)
930 unsigned long i
, chunks
, index
, oldindex
, bit
;
931 struct page
*page
= NULL
;
932 unsigned long bit_cnt
= 0;
934 unsigned long offset
;
938 struct bitmap_storage
*store
= &bitmap
->storage
;
940 chunks
= bitmap
->counts
.chunks
;
943 if (!file
&& !bitmap
->mddev
->bitmap_info
.offset
) {
944 /* No permanent bitmap - fill with '1s'. */
945 store
->filemap
= NULL
;
946 store
->file_pages
= 0;
947 for (i
= 0; i
< chunks
; i
++) {
948 /* if the disk bit is set, set the memory bit */
949 int needed
= ((sector_t
)(i
+1) << (bitmap
->counts
.chunkshift
)
951 bitmap_set_memory_bits(bitmap
,
952 (sector_t
)i
<< bitmap
->counts
.chunkshift
,
958 outofdate
= test_bit(BITMAP_STALE
, &bitmap
->flags
);
960 printk(KERN_INFO
"%s: bitmap file is out of date, doing full "
961 "recovery\n", bmname(bitmap
));
963 if (file
&& i_size_read(file
->f_mapping
->host
) < store
->bytes
) {
964 printk(KERN_INFO
"%s: bitmap file too short %lu < %lu\n",
966 (unsigned long) i_size_read(file
->f_mapping
->host
),
973 if (!bitmap
->mddev
->bitmap_info
.external
)
974 offset
= sizeof(bitmap_super_t
);
976 for (i
= 0; i
< chunks
; i
++) {
978 index
= file_page_index(&bitmap
->storage
, i
);
979 bit
= file_page_offset(&bitmap
->storage
, i
);
980 if (index
!= oldindex
) { /* this is a new page, read it in */
982 /* unmap the old page, we're done with it */
983 if (index
== store
->file_pages
-1)
984 count
= store
->bytes
- index
* PAGE_SIZE
;
987 page
= store
->filemap
[index
];
989 ret
= read_page(file
, index
, bitmap
,
994 bitmap
->mddev
->bitmap_info
.offset
,
1005 * if bitmap is out of date, dirty the
1006 * whole page and write it out
1008 paddr
= kmap_atomic(page
);
1009 memset(paddr
+ offset
, 0xff,
1010 PAGE_SIZE
- offset
);
1011 kunmap_atomic(paddr
);
1012 write_page(bitmap
, page
, 1);
1015 if (test_bit(BITMAP_WRITE_ERROR
,
1020 paddr
= kmap_atomic(page
);
1021 if (test_bit(BITMAP_HOSTENDIAN
, &bitmap
->flags
))
1022 b
= test_bit(bit
, paddr
);
1024 b
= test_bit_le(bit
, paddr
);
1025 kunmap_atomic(paddr
);
1027 /* if the disk bit is set, set the memory bit */
1028 int needed
= ((sector_t
)(i
+1) << bitmap
->counts
.chunkshift
1030 bitmap_set_memory_bits(bitmap
,
1031 (sector_t
)i
<< bitmap
->counts
.chunkshift
,
1038 printk(KERN_INFO
"%s: bitmap initialized from disk: "
1039 "read %lu pages, set %lu of %lu bits\n",
1040 bmname(bitmap
), store
->file_pages
,
1046 printk(KERN_INFO
"%s: bitmap initialisation failed: %d\n",
1047 bmname(bitmap
), ret
);
1051 void bitmap_write_all(struct bitmap
*bitmap
)
1053 /* We don't actually write all bitmap blocks here,
1054 * just flag them as needing to be written
1058 if (!bitmap
|| !bitmap
->storage
.filemap
)
1060 if (bitmap
->storage
.file
)
1061 /* Only one copy, so nothing needed */
1064 for (i
= 0; i
< bitmap
->storage
.file_pages
; i
++)
1065 set_page_attr(bitmap
, i
,
1066 BITMAP_PAGE_NEEDWRITE
);
1067 bitmap
->allclean
= 0;
1070 static void bitmap_count_page(struct bitmap_counts
*bitmap
,
1071 sector_t offset
, int inc
)
1073 sector_t chunk
= offset
>> bitmap
->chunkshift
;
1074 unsigned long page
= chunk
>> PAGE_COUNTER_SHIFT
;
1075 bitmap
->bp
[page
].count
+= inc
;
1076 bitmap_checkfree(bitmap
, page
);
1079 static void bitmap_set_pending(struct bitmap_counts
*bitmap
, sector_t offset
)
1081 sector_t chunk
= offset
>> bitmap
->chunkshift
;
1082 unsigned long page
= chunk
>> PAGE_COUNTER_SHIFT
;
1083 struct bitmap_page
*bp
= &bitmap
->bp
[page
];
1089 static bitmap_counter_t
*bitmap_get_counter(struct bitmap_counts
*bitmap
,
1090 sector_t offset
, sector_t
*blocks
,
1094 * bitmap daemon -- periodically wakes up to clean bits and flush pages
1098 void bitmap_daemon_work(struct mddev
*mddev
)
1100 struct bitmap
*bitmap
;
1102 unsigned long nextpage
;
1104 struct bitmap_counts
*counts
;
1106 /* Use a mutex to guard daemon_work against
1109 mutex_lock(&mddev
->bitmap_info
.mutex
);
1110 bitmap
= mddev
->bitmap
;
1111 if (bitmap
== NULL
) {
1112 mutex_unlock(&mddev
->bitmap_info
.mutex
);
1115 if (time_before(jiffies
, bitmap
->daemon_lastrun
1116 + mddev
->bitmap_info
.daemon_sleep
))
1119 bitmap
->daemon_lastrun
= jiffies
;
1120 if (bitmap
->allclean
) {
1121 mddev
->thread
->timeout
= MAX_SCHEDULE_TIMEOUT
;
1124 bitmap
->allclean
= 1;
1126 /* Any file-page which is PENDING now needs to be written.
1127 * So set NEEDWRITE now, then after we make any last-minute changes
1130 for (j
= 0; j
< bitmap
->storage
.file_pages
; j
++)
1131 if (test_and_clear_page_attr(bitmap
, j
,
1132 BITMAP_PAGE_PENDING
))
1133 set_page_attr(bitmap
, j
,
1134 BITMAP_PAGE_NEEDWRITE
);
1136 if (bitmap
->need_sync
&&
1137 mddev
->bitmap_info
.external
== 0) {
1138 /* Arrange for superblock update as well as
1141 bitmap
->need_sync
= 0;
1142 if (bitmap
->storage
.filemap
) {
1143 sb
= kmap_atomic(bitmap
->storage
.sb_page
);
1144 sb
->events_cleared
=
1145 cpu_to_le64(bitmap
->events_cleared
);
1147 set_page_attr(bitmap
, 0,
1148 BITMAP_PAGE_NEEDWRITE
);
1151 /* Now look at the bitmap counters and if any are '2' or '1',
1152 * decrement and handle accordingly.
1154 counts
= &bitmap
->counts
;
1155 spin_lock_irq(&counts
->lock
);
1157 for (j
= 0; j
< counts
->chunks
; j
++) {
1158 bitmap_counter_t
*bmc
;
1159 sector_t block
= (sector_t
)j
<< counts
->chunkshift
;
1161 if (j
== nextpage
) {
1162 nextpage
+= PAGE_COUNTER_RATIO
;
1163 if (!counts
->bp
[j
>> PAGE_COUNTER_SHIFT
].pending
) {
1164 j
|= PAGE_COUNTER_MASK
;
1167 counts
->bp
[j
>> PAGE_COUNTER_SHIFT
].pending
= 0;
1169 bmc
= bitmap_get_counter(counts
,
1174 j
|= PAGE_COUNTER_MASK
;
1177 if (*bmc
== 1 && !bitmap
->need_sync
) {
1178 /* We can clear the bit */
1180 bitmap_count_page(counts
, block
, -1);
1181 bitmap_file_clear_bit(bitmap
, block
);
1182 } else if (*bmc
&& *bmc
<= 2) {
1184 bitmap_set_pending(counts
, block
);
1185 bitmap
->allclean
= 0;
1188 spin_unlock_irq(&counts
->lock
);
1190 /* Now start writeout on any page in NEEDWRITE that isn't DIRTY.
1191 * DIRTY pages need to be written by bitmap_unplug so it can wait
1193 * If we find any DIRTY page we stop there and let bitmap_unplug
1194 * handle all the rest. This is important in the case where
1195 * the first blocking holds the superblock and it has been updated.
1196 * We mustn't write any other blocks before the superblock.
1199 j
< bitmap
->storage
.file_pages
1200 && !test_bit(BITMAP_STALE
, &bitmap
->flags
);
1203 if (test_page_attr(bitmap
, j
,
1205 /* bitmap_unplug will handle the rest */
1207 if (test_and_clear_page_attr(bitmap
, j
,
1208 BITMAP_PAGE_NEEDWRITE
)) {
1209 write_page(bitmap
, bitmap
->storage
.filemap
[j
], 0);
1214 if (bitmap
->allclean
== 0)
1215 mddev
->thread
->timeout
=
1216 mddev
->bitmap_info
.daemon_sleep
;
1217 mutex_unlock(&mddev
->bitmap_info
.mutex
);
1220 static bitmap_counter_t
*bitmap_get_counter(struct bitmap_counts
*bitmap
,
1221 sector_t offset
, sector_t
*blocks
,
1223 __releases(bitmap
->lock
)
1224 __acquires(bitmap
->lock
)
1226 /* If 'create', we might release the lock and reclaim it.
1227 * The lock must have been taken with interrupts enabled.
1228 * If !create, we don't release the lock.
1230 sector_t chunk
= offset
>> bitmap
->chunkshift
;
1231 unsigned long page
= chunk
>> PAGE_COUNTER_SHIFT
;
1232 unsigned long pageoff
= (chunk
& PAGE_COUNTER_MASK
) << COUNTER_BYTE_SHIFT
;
1236 err
= bitmap_checkpage(bitmap
, page
, create
);
1238 if (bitmap
->bp
[page
].hijacked
||
1239 bitmap
->bp
[page
].map
== NULL
)
1240 csize
= ((sector_t
)1) << (bitmap
->chunkshift
+
1241 PAGE_COUNTER_SHIFT
- 1);
1243 csize
= ((sector_t
)1) << bitmap
->chunkshift
;
1244 *blocks
= csize
- (offset
& (csize
- 1));
1249 /* now locked ... */
1251 if (bitmap
->bp
[page
].hijacked
) { /* hijacked pointer */
1252 /* should we use the first or second counter field
1253 * of the hijacked pointer? */
1254 int hi
= (pageoff
> PAGE_COUNTER_MASK
);
1255 return &((bitmap_counter_t
*)
1256 &bitmap
->bp
[page
].map
)[hi
];
1257 } else /* page is allocated */
1258 return (bitmap_counter_t
*)
1259 &(bitmap
->bp
[page
].map
[pageoff
]);
1262 int bitmap_startwrite(struct bitmap
*bitmap
, sector_t offset
, unsigned long sectors
, int behind
)
1269 atomic_inc(&bitmap
->behind_writes
);
1270 bw
= atomic_read(&bitmap
->behind_writes
);
1271 if (bw
> bitmap
->behind_writes_used
)
1272 bitmap
->behind_writes_used
= bw
;
1274 pr_debug("inc write-behind count %d/%lu\n",
1275 bw
, bitmap
->mddev
->bitmap_info
.max_write_behind
);
1280 bitmap_counter_t
*bmc
;
1282 spin_lock_irq(&bitmap
->counts
.lock
);
1283 bmc
= bitmap_get_counter(&bitmap
->counts
, offset
, &blocks
, 1);
1285 spin_unlock_irq(&bitmap
->counts
.lock
);
1289 if (unlikely(COUNTER(*bmc
) == COUNTER_MAX
)) {
1290 DEFINE_WAIT(__wait
);
1291 /* note that it is safe to do the prepare_to_wait
1292 * after the test as long as we do it before dropping
1295 prepare_to_wait(&bitmap
->overflow_wait
, &__wait
,
1296 TASK_UNINTERRUPTIBLE
);
1297 spin_unlock_irq(&bitmap
->counts
.lock
);
1299 finish_wait(&bitmap
->overflow_wait
, &__wait
);
1305 bitmap_file_set_bit(bitmap
, offset
);
1306 bitmap_count_page(&bitmap
->counts
, offset
, 1);
1314 spin_unlock_irq(&bitmap
->counts
.lock
);
1317 if (sectors
> blocks
)
1324 EXPORT_SYMBOL(bitmap_startwrite
);
1326 void bitmap_endwrite(struct bitmap
*bitmap
, sector_t offset
, unsigned long sectors
,
1327 int success
, int behind
)
1332 if (atomic_dec_and_test(&bitmap
->behind_writes
))
1333 wake_up(&bitmap
->behind_wait
);
1334 pr_debug("dec write-behind count %d/%lu\n",
1335 atomic_read(&bitmap
->behind_writes
),
1336 bitmap
->mddev
->bitmap_info
.max_write_behind
);
1341 unsigned long flags
;
1342 bitmap_counter_t
*bmc
;
1344 spin_lock_irqsave(&bitmap
->counts
.lock
, flags
);
1345 bmc
= bitmap_get_counter(&bitmap
->counts
, offset
, &blocks
, 0);
1347 spin_unlock_irqrestore(&bitmap
->counts
.lock
, flags
);
1351 if (success
&& !bitmap
->mddev
->degraded
&&
1352 bitmap
->events_cleared
< bitmap
->mddev
->events
) {
1353 bitmap
->events_cleared
= bitmap
->mddev
->events
;
1354 bitmap
->need_sync
= 1;
1355 sysfs_notify_dirent_safe(bitmap
->sysfs_can_clear
);
1358 if (!success
&& !NEEDED(*bmc
))
1359 *bmc
|= NEEDED_MASK
;
1361 if (COUNTER(*bmc
) == COUNTER_MAX
)
1362 wake_up(&bitmap
->overflow_wait
);
1366 bitmap_set_pending(&bitmap
->counts
, offset
);
1367 bitmap
->allclean
= 0;
1369 spin_unlock_irqrestore(&bitmap
->counts
.lock
, flags
);
1371 if (sectors
> blocks
)
1377 EXPORT_SYMBOL(bitmap_endwrite
);
1379 static int __bitmap_start_sync(struct bitmap
*bitmap
, sector_t offset
, sector_t
*blocks
,
1382 bitmap_counter_t
*bmc
;
1384 if (bitmap
== NULL
) {/* FIXME or bitmap set as 'failed' */
1386 return 1; /* always resync if no bitmap */
1388 spin_lock_irq(&bitmap
->counts
.lock
);
1389 bmc
= bitmap_get_counter(&bitmap
->counts
, offset
, blocks
, 0);
1395 else if (NEEDED(*bmc
)) {
1397 if (!degraded
) { /* don't set/clear bits if degraded */
1398 *bmc
|= RESYNC_MASK
;
1399 *bmc
&= ~NEEDED_MASK
;
1403 spin_unlock_irq(&bitmap
->counts
.lock
);
1407 int bitmap_start_sync(struct bitmap
*bitmap
, sector_t offset
, sector_t
*blocks
,
1410 /* bitmap_start_sync must always report on multiples of whole
1411 * pages, otherwise resync (which is very PAGE_SIZE based) will
1413 * So call __bitmap_start_sync repeatedly (if needed) until
1414 * At least PAGE_SIZE>>9 blocks are covered.
1415 * Return the 'or' of the result.
1421 while (*blocks
< (PAGE_SIZE
>>9)) {
1422 rv
|= __bitmap_start_sync(bitmap
, offset
,
1423 &blocks1
, degraded
);
1429 EXPORT_SYMBOL(bitmap_start_sync
);
1431 void bitmap_end_sync(struct bitmap
*bitmap
, sector_t offset
, sector_t
*blocks
, int aborted
)
1433 bitmap_counter_t
*bmc
;
1434 unsigned long flags
;
1436 if (bitmap
== NULL
) {
1440 spin_lock_irqsave(&bitmap
->counts
.lock
, flags
);
1441 bmc
= bitmap_get_counter(&bitmap
->counts
, offset
, blocks
, 0);
1446 *bmc
&= ~RESYNC_MASK
;
1448 if (!NEEDED(*bmc
) && aborted
)
1449 *bmc
|= NEEDED_MASK
;
1452 bitmap_set_pending(&bitmap
->counts
, offset
);
1453 bitmap
->allclean
= 0;
1458 spin_unlock_irqrestore(&bitmap
->counts
.lock
, flags
);
1460 EXPORT_SYMBOL(bitmap_end_sync
);
1462 void bitmap_close_sync(struct bitmap
*bitmap
)
1464 /* Sync has finished, and any bitmap chunks that weren't synced
1465 * properly have been aborted. It remains to us to clear the
1466 * RESYNC bit wherever it is still on
1468 sector_t sector
= 0;
1472 while (sector
< bitmap
->mddev
->resync_max_sectors
) {
1473 bitmap_end_sync(bitmap
, sector
, &blocks
, 0);
1477 EXPORT_SYMBOL(bitmap_close_sync
);
1479 void bitmap_cond_end_sync(struct bitmap
*bitmap
, sector_t sector
)
1487 bitmap
->last_end_sync
= jiffies
;
1490 if (time_before(jiffies
, (bitmap
->last_end_sync
1491 + bitmap
->mddev
->bitmap_info
.daemon_sleep
)))
1493 wait_event(bitmap
->mddev
->recovery_wait
,
1494 atomic_read(&bitmap
->mddev
->recovery_active
) == 0);
1496 bitmap
->mddev
->curr_resync_completed
= sector
;
1497 set_bit(MD_CHANGE_CLEAN
, &bitmap
->mddev
->flags
);
1498 sector
&= ~((1ULL << bitmap
->counts
.chunkshift
) - 1);
1500 while (s
< sector
&& s
< bitmap
->mddev
->resync_max_sectors
) {
1501 bitmap_end_sync(bitmap
, s
, &blocks
, 0);
1504 bitmap
->last_end_sync
= jiffies
;
1505 sysfs_notify(&bitmap
->mddev
->kobj
, NULL
, "sync_completed");
1507 EXPORT_SYMBOL(bitmap_cond_end_sync
);
1509 static void bitmap_set_memory_bits(struct bitmap
*bitmap
, sector_t offset
, int needed
)
1511 /* For each chunk covered by any of these sectors, set the
1512 * counter to 2 and possibly set resync_needed. They should all
1513 * be 0 at this point
1517 bitmap_counter_t
*bmc
;
1518 spin_lock_irq(&bitmap
->counts
.lock
);
1519 bmc
= bitmap_get_counter(&bitmap
->counts
, offset
, &secs
, 1);
1521 spin_unlock_irq(&bitmap
->counts
.lock
);
1525 *bmc
= 2 | (needed
? NEEDED_MASK
: 0);
1526 bitmap_count_page(&bitmap
->counts
, offset
, 1);
1527 bitmap_set_pending(&bitmap
->counts
, offset
);
1528 bitmap
->allclean
= 0;
1530 spin_unlock_irq(&bitmap
->counts
.lock
);
1533 /* dirty the memory and file bits for bitmap chunks "s" to "e" */
1534 void bitmap_dirty_bits(struct bitmap
*bitmap
, unsigned long s
, unsigned long e
)
1536 unsigned long chunk
;
1538 for (chunk
= s
; chunk
<= e
; chunk
++) {
1539 sector_t sec
= (sector_t
)chunk
<< bitmap
->counts
.chunkshift
;
1540 bitmap_set_memory_bits(bitmap
, sec
, 1);
1541 bitmap_file_set_bit(bitmap
, sec
);
1542 if (sec
< bitmap
->mddev
->recovery_cp
)
1543 /* We are asserting that the array is dirty,
1544 * so move the recovery_cp address back so
1545 * that it is obvious that it is dirty
1547 bitmap
->mddev
->recovery_cp
= sec
;
1552 * flush out any pending updates
1554 void bitmap_flush(struct mddev
*mddev
)
1556 struct bitmap
*bitmap
= mddev
->bitmap
;
1559 if (!bitmap
) /* there was no bitmap */
1562 /* run the daemon_work three time to ensure everything is flushed
1565 sleep
= mddev
->bitmap_info
.daemon_sleep
* 2;
1566 bitmap
->daemon_lastrun
-= sleep
;
1567 bitmap_daemon_work(mddev
);
1568 bitmap
->daemon_lastrun
-= sleep
;
1569 bitmap_daemon_work(mddev
);
1570 bitmap
->daemon_lastrun
-= sleep
;
1571 bitmap_daemon_work(mddev
);
1572 bitmap_update_sb(bitmap
);
1576 * free memory that was allocated
1578 static void bitmap_free(struct bitmap
*bitmap
)
1580 unsigned long k
, pages
;
1581 struct bitmap_page
*bp
;
1583 if (!bitmap
) /* there was no bitmap */
1586 /* Shouldn't be needed - but just in case.... */
1587 wait_event(bitmap
->write_wait
,
1588 atomic_read(&bitmap
->pending_writes
) == 0);
1590 /* release the bitmap file */
1591 bitmap_file_unmap(&bitmap
->storage
);
1593 bp
= bitmap
->counts
.bp
;
1594 pages
= bitmap
->counts
.pages
;
1596 /* free all allocated memory */
1598 if (bp
) /* deallocate the page memory */
1599 for (k
= 0; k
< pages
; k
++)
1600 if (bp
[k
].map
&& !bp
[k
].hijacked
)
1606 void bitmap_destroy(struct mddev
*mddev
)
1608 struct bitmap
*bitmap
= mddev
->bitmap
;
1610 if (!bitmap
) /* there was no bitmap */
1613 mutex_lock(&mddev
->bitmap_info
.mutex
);
1614 mddev
->bitmap
= NULL
; /* disconnect from the md device */
1615 mutex_unlock(&mddev
->bitmap_info
.mutex
);
1617 mddev
->thread
->timeout
= MAX_SCHEDULE_TIMEOUT
;
1619 if (bitmap
->sysfs_can_clear
)
1620 sysfs_put(bitmap
->sysfs_can_clear
);
1622 bitmap_free(bitmap
);
1626 * initialize the bitmap structure
1627 * if this returns an error, bitmap_destroy must be called to do clean up
1629 int bitmap_create(struct mddev
*mddev
)
1631 struct bitmap
*bitmap
;
1632 sector_t blocks
= mddev
->resync_max_sectors
;
1633 unsigned long chunks
;
1634 unsigned long pages
;
1635 struct file
*file
= mddev
->bitmap_info
.file
;
1637 struct sysfs_dirent
*bm
= NULL
;
1639 BUILD_BUG_ON(sizeof(bitmap_super_t
) != 256);
1641 BUG_ON(file
&& mddev
->bitmap_info
.offset
);
1643 bitmap
= kzalloc(sizeof(*bitmap
), GFP_KERNEL
);
1647 spin_lock_init(&bitmap
->counts
.lock
);
1648 atomic_set(&bitmap
->pending_writes
, 0);
1649 init_waitqueue_head(&bitmap
->write_wait
);
1650 init_waitqueue_head(&bitmap
->overflow_wait
);
1651 init_waitqueue_head(&bitmap
->behind_wait
);
1653 bitmap
->mddev
= mddev
;
1656 bm
= sysfs_get_dirent(mddev
->kobj
.sd
, NULL
, "bitmap");
1658 bitmap
->sysfs_can_clear
= sysfs_get_dirent(bm
, NULL
, "can_clear");
1661 bitmap
->sysfs_can_clear
= NULL
;
1663 bitmap
->storage
.file
= file
;
1666 /* As future accesses to this file will use bmap,
1667 * and bypass the page cache, we must sync the file
1672 /* read superblock from bitmap file (this sets mddev->bitmap_info.chunksize) */
1673 if (!mddev
->bitmap_info
.external
) {
1675 * If 'MD_ARRAY_FIRST_USE' is set, then device-mapper is
1676 * instructing us to create a new on-disk bitmap instance.
1678 if (test_and_clear_bit(MD_ARRAY_FIRST_USE
, &mddev
->flags
))
1679 err
= bitmap_new_disk_sb(bitmap
);
1681 err
= bitmap_read_sb(bitmap
);
1684 if (mddev
->bitmap_info
.chunksize
== 0 ||
1685 mddev
->bitmap_info
.daemon_sleep
== 0)
1686 /* chunksize and time_base need to be
1693 bitmap
->daemon_lastrun
= jiffies
;
1694 bitmap
->counts
.chunkshift
= (ffz(~mddev
->bitmap_info
.chunksize
)
1695 - BITMAP_BLOCK_SHIFT
);
1697 chunks
= (blocks
+ (1 << bitmap
->counts
.chunkshift
) - 1) >>
1698 bitmap
->counts
.chunkshift
;
1699 pages
= (chunks
+ PAGE_COUNTER_RATIO
- 1) / PAGE_COUNTER_RATIO
;
1703 bitmap
->counts
.chunks
= chunks
;
1704 bitmap
->counts
.pages
= pages
;
1705 bitmap
->counts
.missing_pages
= pages
;
1707 bitmap
->counts
.bp
= kzalloc(pages
* sizeof(*bitmap
->counts
.bp
),
1711 if (!bitmap
->counts
.bp
)
1714 if (file
|| mddev
->bitmap_info
.offset
) {
1715 err
= bitmap_storage_alloc(&bitmap
->storage
, bitmap
->counts
.chunks
,
1716 !mddev
->bitmap_info
.external
);
1720 printk(KERN_INFO
"created bitmap (%lu pages) for device %s\n",
1721 pages
, bmname(bitmap
));
1723 mddev
->bitmap
= bitmap
;
1726 return test_bit(BITMAP_WRITE_ERROR
, &bitmap
->flags
) ? -EIO
: 0;
1729 bitmap_free(bitmap
);
1733 int bitmap_load(struct mddev
*mddev
)
1737 sector_t sector
= 0;
1738 struct bitmap
*bitmap
= mddev
->bitmap
;
1743 /* Clear out old bitmap info first: Either there is none, or we
1744 * are resuming after someone else has possibly changed things,
1745 * so we should forget old cached info.
1746 * All chunks should be clean, but some might need_sync.
1748 while (sector
< mddev
->resync_max_sectors
) {
1750 bitmap_start_sync(bitmap
, sector
, &blocks
, 0);
1753 bitmap_close_sync(bitmap
);
1755 if (mddev
->degraded
== 0
1756 || bitmap
->events_cleared
== mddev
->events
)
1757 /* no need to keep dirty bits to optimise a
1758 * re-add of a missing device */
1759 start
= mddev
->recovery_cp
;
1761 mutex_lock(&mddev
->bitmap_info
.mutex
);
1762 err
= bitmap_init_from_disk(bitmap
, start
);
1763 mutex_unlock(&mddev
->bitmap_info
.mutex
);
1767 clear_bit(BITMAP_STALE
, &bitmap
->flags
);
1769 /* Kick recovery in case any bits were set */
1770 set_bit(MD_RECOVERY_NEEDED
, &bitmap
->mddev
->recovery
);
1772 mddev
->thread
->timeout
= mddev
->bitmap_info
.daemon_sleep
;
1773 md_wakeup_thread(mddev
->thread
);
1775 bitmap_update_sb(bitmap
);
1777 if (test_bit(BITMAP_WRITE_ERROR
, &bitmap
->flags
))
1782 EXPORT_SYMBOL_GPL(bitmap_load
);
1784 void bitmap_status(struct seq_file
*seq
, struct bitmap
*bitmap
)
1786 unsigned long chunk_kb
;
1787 struct bitmap_counts
*counts
;
1792 counts
= &bitmap
->counts
;
1794 chunk_kb
= bitmap
->mddev
->bitmap_info
.chunksize
>> 10;
1795 seq_printf(seq
, "bitmap: %lu/%lu pages [%luKB], "
1797 counts
->pages
- counts
->missing_pages
,
1799 (counts
->pages
- counts
->missing_pages
)
1800 << (PAGE_SHIFT
- 10),
1801 chunk_kb
? chunk_kb
: bitmap
->mddev
->bitmap_info
.chunksize
,
1802 chunk_kb
? "KB" : "B");
1803 if (bitmap
->storage
.file
) {
1804 seq_printf(seq
, ", file: ");
1805 seq_path(seq
, &bitmap
->storage
.file
->f_path
, " \t\n");
1808 seq_printf(seq
, "\n");
1812 location_show(struct mddev
*mddev
, char *page
)
1815 if (mddev
->bitmap_info
.file
)
1816 len
= sprintf(page
, "file");
1817 else if (mddev
->bitmap_info
.offset
)
1818 len
= sprintf(page
, "%+lld", (long long)mddev
->bitmap_info
.offset
);
1820 len
= sprintf(page
, "none");
1821 len
+= sprintf(page
+len
, "\n");
1826 location_store(struct mddev
*mddev
, const char *buf
, size_t len
)
1830 if (!mddev
->pers
->quiesce
)
1832 if (mddev
->recovery
|| mddev
->sync_thread
)
1836 if (mddev
->bitmap
|| mddev
->bitmap_info
.file
||
1837 mddev
->bitmap_info
.offset
) {
1838 /* bitmap already configured. Only option is to clear it */
1839 if (strncmp(buf
, "none", 4) != 0)
1842 mddev
->pers
->quiesce(mddev
, 1);
1843 bitmap_destroy(mddev
);
1844 mddev
->pers
->quiesce(mddev
, 0);
1846 mddev
->bitmap_info
.offset
= 0;
1847 if (mddev
->bitmap_info
.file
) {
1848 struct file
*f
= mddev
->bitmap_info
.file
;
1849 mddev
->bitmap_info
.file
= NULL
;
1850 restore_bitmap_write_access(f
);
1854 /* No bitmap, OK to set a location */
1856 if (strncmp(buf
, "none", 4) == 0)
1857 /* nothing to be done */;
1858 else if (strncmp(buf
, "file:", 5) == 0) {
1859 /* Not supported yet */
1864 rv
= strict_strtoll(buf
+1, 10, &offset
);
1866 rv
= strict_strtoll(buf
, 10, &offset
);
1871 if (mddev
->bitmap_info
.external
== 0 &&
1872 mddev
->major_version
== 0 &&
1873 offset
!= mddev
->bitmap_info
.default_offset
)
1875 mddev
->bitmap_info
.offset
= offset
;
1877 mddev
->pers
->quiesce(mddev
, 1);
1878 rv
= bitmap_create(mddev
);
1880 rv
= bitmap_load(mddev
);
1882 bitmap_destroy(mddev
);
1883 mddev
->bitmap_info
.offset
= 0;
1885 mddev
->pers
->quiesce(mddev
, 0);
1891 if (!mddev
->external
) {
1892 /* Ensure new bitmap info is stored in
1893 * metadata promptly.
1895 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
1896 md_wakeup_thread(mddev
->thread
);
1901 static struct md_sysfs_entry bitmap_location
=
1902 __ATTR(location
, S_IRUGO
|S_IWUSR
, location_show
, location_store
);
1904 /* 'bitmap/space' is the space available at 'location' for the
1905 * bitmap. This allows the kernel to know when it is safe to
1906 * resize the bitmap to match a resized array.
1909 space_show(struct mddev
*mddev
, char *page
)
1911 return sprintf(page
, "%lu\n", mddev
->bitmap_info
.space
);
1915 space_store(struct mddev
*mddev
, const char *buf
, size_t len
)
1917 unsigned long sectors
;
1920 rv
= kstrtoul(buf
, 10, §ors
);
1927 if (mddev
->bitmap
&&
1928 sectors
< (mddev
->bitmap
->storage
.bytes
+ 511) >> 9)
1929 return -EFBIG
; /* Bitmap is too big for this small space */
1931 /* could make sure it isn't too big, but that isn't really
1932 * needed - user-space should be careful.
1934 mddev
->bitmap_info
.space
= sectors
;
1938 static struct md_sysfs_entry bitmap_space
=
1939 __ATTR(space
, S_IRUGO
|S_IWUSR
, space_show
, space_store
);
1942 timeout_show(struct mddev
*mddev
, char *page
)
1945 unsigned long secs
= mddev
->bitmap_info
.daemon_sleep
/ HZ
;
1946 unsigned long jifs
= mddev
->bitmap_info
.daemon_sleep
% HZ
;
1948 len
= sprintf(page
, "%lu", secs
);
1950 len
+= sprintf(page
+len
, ".%03u", jiffies_to_msecs(jifs
));
1951 len
+= sprintf(page
+len
, "\n");
1956 timeout_store(struct mddev
*mddev
, const char *buf
, size_t len
)
1958 /* timeout can be set at any time */
1959 unsigned long timeout
;
1960 int rv
= strict_strtoul_scaled(buf
, &timeout
, 4);
1964 /* just to make sure we don't overflow... */
1965 if (timeout
>= LONG_MAX
/ HZ
)
1968 timeout
= timeout
* HZ
/ 10000;
1970 if (timeout
>= MAX_SCHEDULE_TIMEOUT
)
1971 timeout
= MAX_SCHEDULE_TIMEOUT
-1;
1974 mddev
->bitmap_info
.daemon_sleep
= timeout
;
1975 if (mddev
->thread
) {
1976 /* if thread->timeout is MAX_SCHEDULE_TIMEOUT, then
1977 * the bitmap is all clean and we don't need to
1978 * adjust the timeout right now
1980 if (mddev
->thread
->timeout
< MAX_SCHEDULE_TIMEOUT
) {
1981 mddev
->thread
->timeout
= timeout
;
1982 md_wakeup_thread(mddev
->thread
);
1988 static struct md_sysfs_entry bitmap_timeout
=
1989 __ATTR(time_base
, S_IRUGO
|S_IWUSR
, timeout_show
, timeout_store
);
1992 backlog_show(struct mddev
*mddev
, char *page
)
1994 return sprintf(page
, "%lu\n", mddev
->bitmap_info
.max_write_behind
);
1998 backlog_store(struct mddev
*mddev
, const char *buf
, size_t len
)
2000 unsigned long backlog
;
2001 int rv
= strict_strtoul(buf
, 10, &backlog
);
2004 if (backlog
> COUNTER_MAX
)
2006 mddev
->bitmap_info
.max_write_behind
= backlog
;
2010 static struct md_sysfs_entry bitmap_backlog
=
2011 __ATTR(backlog
, S_IRUGO
|S_IWUSR
, backlog_show
, backlog_store
);
2014 chunksize_show(struct mddev
*mddev
, char *page
)
2016 return sprintf(page
, "%lu\n", mddev
->bitmap_info
.chunksize
);
2020 chunksize_store(struct mddev
*mddev
, const char *buf
, size_t len
)
2022 /* Can only be changed when no bitmap is active */
2024 unsigned long csize
;
2027 rv
= strict_strtoul(buf
, 10, &csize
);
2031 !is_power_of_2(csize
))
2033 mddev
->bitmap_info
.chunksize
= csize
;
2037 static struct md_sysfs_entry bitmap_chunksize
=
2038 __ATTR(chunksize
, S_IRUGO
|S_IWUSR
, chunksize_show
, chunksize_store
);
2040 static ssize_t
metadata_show(struct mddev
*mddev
, char *page
)
2042 return sprintf(page
, "%s\n", (mddev
->bitmap_info
.external
2043 ? "external" : "internal"));
2046 static ssize_t
metadata_store(struct mddev
*mddev
, const char *buf
, size_t len
)
2048 if (mddev
->bitmap
||
2049 mddev
->bitmap_info
.file
||
2050 mddev
->bitmap_info
.offset
)
2052 if (strncmp(buf
, "external", 8) == 0)
2053 mddev
->bitmap_info
.external
= 1;
2054 else if (strncmp(buf
, "internal", 8) == 0)
2055 mddev
->bitmap_info
.external
= 0;
2061 static struct md_sysfs_entry bitmap_metadata
=
2062 __ATTR(metadata
, S_IRUGO
|S_IWUSR
, metadata_show
, metadata_store
);
2064 static ssize_t
can_clear_show(struct mddev
*mddev
, char *page
)
2068 len
= sprintf(page
, "%s\n", (mddev
->bitmap
->need_sync
?
2071 len
= sprintf(page
, "\n");
2075 static ssize_t
can_clear_store(struct mddev
*mddev
, const char *buf
, size_t len
)
2077 if (mddev
->bitmap
== NULL
)
2079 if (strncmp(buf
, "false", 5) == 0)
2080 mddev
->bitmap
->need_sync
= 1;
2081 else if (strncmp(buf
, "true", 4) == 0) {
2082 if (mddev
->degraded
)
2084 mddev
->bitmap
->need_sync
= 0;
2090 static struct md_sysfs_entry bitmap_can_clear
=
2091 __ATTR(can_clear
, S_IRUGO
|S_IWUSR
, can_clear_show
, can_clear_store
);
2094 behind_writes_used_show(struct mddev
*mddev
, char *page
)
2096 if (mddev
->bitmap
== NULL
)
2097 return sprintf(page
, "0\n");
2098 return sprintf(page
, "%lu\n",
2099 mddev
->bitmap
->behind_writes_used
);
2103 behind_writes_used_reset(struct mddev
*mddev
, const char *buf
, size_t len
)
2106 mddev
->bitmap
->behind_writes_used
= 0;
2110 static struct md_sysfs_entry max_backlog_used
=
2111 __ATTR(max_backlog_used
, S_IRUGO
| S_IWUSR
,
2112 behind_writes_used_show
, behind_writes_used_reset
);
2114 static struct attribute
*md_bitmap_attrs
[] = {
2115 &bitmap_location
.attr
,
2117 &bitmap_timeout
.attr
,
2118 &bitmap_backlog
.attr
,
2119 &bitmap_chunksize
.attr
,
2120 &bitmap_metadata
.attr
,
2121 &bitmap_can_clear
.attr
,
2122 &max_backlog_used
.attr
,
2125 struct attribute_group md_bitmap_group
= {
2127 .attrs
= md_bitmap_attrs
,