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
*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("%s: bitmap map page allocation failed, hijacking\n",
81 /* failed - set the hijacked flag so that we can use the
82 * pointer as a counter */
83 if (!bitmap
->bp
[page
].map
)
84 bitmap
->bp
[page
].hijacked
= 1;
85 } else if (bitmap
->bp
[page
].map
||
86 bitmap
->bp
[page
].hijacked
) {
87 /* somebody beat us to getting the page */
92 /* no page was in place and we have one, so install it */
94 bitmap
->bp
[page
].map
= mappage
;
95 bitmap
->missing_pages
--;
100 /* if page is completely empty, put it back on the free list, or dealloc it */
101 /* if page was hijacked, unmark the flag so it might get alloced next time */
102 /* Note: lock should be held when calling this */
103 static void bitmap_checkfree(struct bitmap
*bitmap
, unsigned long page
)
107 if (bitmap
->bp
[page
].count
) /* page is still busy */
110 /* page is no longer in use, it can be released */
112 if (bitmap
->bp
[page
].hijacked
) { /* page was hijacked, undo this now */
113 bitmap
->bp
[page
].hijacked
= 0;
114 bitmap
->bp
[page
].map
= NULL
;
116 /* normal case, free the page */
117 ptr
= bitmap
->bp
[page
].map
;
118 bitmap
->bp
[page
].map
= NULL
;
119 bitmap
->missing_pages
++;
125 * bitmap file handling - read and write the bitmap file and its superblock
129 * basic page I/O operations
132 /* IO operations when bitmap is stored near all superblocks */
133 static int read_sb_page(struct mddev
*mddev
, loff_t offset
,
135 unsigned long index
, int size
)
137 /* choose a good rdev and read the page from there */
139 struct md_rdev
*rdev
;
142 rdev_for_each(rdev
, mddev
) {
143 if (! test_bit(In_sync
, &rdev
->flags
)
144 || test_bit(Faulty
, &rdev
->flags
))
147 target
= offset
+ index
* (PAGE_SIZE
/512);
149 if (sync_page_io(rdev
, target
,
150 roundup(size
, bdev_logical_block_size(rdev
->bdev
)),
159 static struct md_rdev
*next_active_rdev(struct md_rdev
*rdev
, struct mddev
*mddev
)
161 /* Iterate the disks of an mddev, using rcu to protect access to the
162 * linked list, and raising the refcount of devices we return to ensure
163 * they don't disappear while in use.
164 * As devices are only added or removed when raid_disk is < 0 and
165 * nr_pending is 0 and In_sync is clear, the entries we return will
166 * still be in the same position on the list when we re-enter
167 * list_for_each_continue_rcu.
169 struct list_head
*pos
;
172 /* start at the beginning */
175 /* release the previous rdev and start from there. */
176 rdev_dec_pending(rdev
, mddev
);
177 pos
= &rdev
->same_set
;
179 list_for_each_continue_rcu(pos
, &mddev
->disks
) {
180 rdev
= list_entry(pos
, struct md_rdev
, same_set
);
181 if (rdev
->raid_disk
>= 0 &&
182 !test_bit(Faulty
, &rdev
->flags
)) {
183 /* this is a usable devices */
184 atomic_inc(&rdev
->nr_pending
);
193 static int write_sb_page(struct bitmap
*bitmap
, struct page
*page
, int wait
)
195 struct md_rdev
*rdev
= NULL
;
196 struct block_device
*bdev
;
197 struct mddev
*mddev
= bitmap
->mddev
;
198 struct bitmap_storage
*store
= &bitmap
->storage
;
200 while ((rdev
= next_active_rdev(rdev
, mddev
)) != NULL
) {
201 int size
= PAGE_SIZE
;
202 loff_t offset
= mddev
->bitmap_info
.offset
;
204 bdev
= (rdev
->meta_bdev
) ? rdev
->meta_bdev
: rdev
->bdev
;
206 if (page
->index
== store
->file_pages
-1)
207 size
= roundup(store
->last_page_size
,
208 bdev_logical_block_size(bdev
));
209 /* Just make sure we aren't corrupting data or
212 if (mddev
->external
) {
213 /* Bitmap could be anywhere. */
214 if (rdev
->sb_start
+ offset
+ (page
->index
218 rdev
->sb_start
+ offset
219 < (rdev
->data_offset
+ mddev
->dev_sectors
222 } else if (offset
< 0) {
223 /* DATA BITMAP METADATA */
225 + (long)(page
->index
* (PAGE_SIZE
/512))
227 /* bitmap runs in to metadata */
229 if (rdev
->data_offset
+ mddev
->dev_sectors
230 > rdev
->sb_start
+ offset
)
231 /* data runs in to bitmap */
233 } else if (rdev
->sb_start
< rdev
->data_offset
) {
234 /* METADATA BITMAP DATA */
237 + page
->index
*(PAGE_SIZE
/512) + size
/512
239 /* bitmap runs in to data */
242 /* DATA METADATA BITMAP - no problems */
244 md_super_write(mddev
, rdev
,
245 rdev
->sb_start
+ offset
246 + page
->index
* (PAGE_SIZE
/512),
252 md_super_wait(mddev
);
259 static void bitmap_file_kick(struct bitmap
*bitmap
);
261 * write out a page to a file
263 static void write_page(struct bitmap
*bitmap
, struct page
*page
, int wait
)
265 struct buffer_head
*bh
;
267 if (bitmap
->storage
.file
== NULL
) {
268 switch (write_sb_page(bitmap
, page
, wait
)) {
270 bitmap
->flags
|= BITMAP_WRITE_ERROR
;
274 bh
= page_buffers(page
);
276 while (bh
&& bh
->b_blocknr
) {
277 atomic_inc(&bitmap
->pending_writes
);
278 set_buffer_locked(bh
);
279 set_buffer_mapped(bh
);
280 submit_bh(WRITE
| REQ_SYNC
, bh
);
281 bh
= bh
->b_this_page
;
285 wait_event(bitmap
->write_wait
,
286 atomic_read(&bitmap
->pending_writes
)==0);
288 if (bitmap
->flags
& BITMAP_WRITE_ERROR
)
289 bitmap_file_kick(bitmap
);
292 static void end_bitmap_write(struct buffer_head
*bh
, int uptodate
)
294 struct bitmap
*bitmap
= bh
->b_private
;
298 spin_lock_irqsave(&bitmap
->lock
, flags
);
299 bitmap
->flags
|= BITMAP_WRITE_ERROR
;
300 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
302 if (atomic_dec_and_test(&bitmap
->pending_writes
))
303 wake_up(&bitmap
->write_wait
);
306 /* copied from buffer.c */
308 __clear_page_buffers(struct page
*page
)
310 ClearPagePrivate(page
);
311 set_page_private(page
, 0);
312 page_cache_release(page
);
314 static void free_buffers(struct page
*page
)
316 struct buffer_head
*bh
;
318 if (!PagePrivate(page
))
321 bh
= page_buffers(page
);
323 struct buffer_head
*next
= bh
->b_this_page
;
324 free_buffer_head(bh
);
327 __clear_page_buffers(page
);
331 /* read a page from a file.
332 * We both read the page, and attach buffers to the page to record the
333 * address of each block (using bmap). These addresses will be used
334 * to write the block later, completely bypassing the filesystem.
335 * This usage is similar to how swap files are handled, and allows us
336 * to write to a file with no concerns of memory allocation failing.
338 static int read_page(struct file
*file
, unsigned long index
,
339 struct bitmap
*bitmap
,
344 struct inode
*inode
= file
->f_path
.dentry
->d_inode
;
345 struct buffer_head
*bh
;
348 pr_debug("read bitmap file (%dB @ %llu)\n", (int)PAGE_SIZE
,
349 (unsigned long long)index
<< PAGE_SHIFT
);
351 bh
= alloc_page_buffers(page
, 1<<inode
->i_blkbits
, 0);
356 attach_page_buffers(page
, bh
);
357 block
= index
<< (PAGE_SHIFT
- inode
->i_blkbits
);
362 bh
->b_blocknr
= bmap(inode
, block
);
363 if (bh
->b_blocknr
== 0) {
364 /* Cannot use this file! */
368 bh
->b_bdev
= inode
->i_sb
->s_bdev
;
369 if (count
< (1<<inode
->i_blkbits
))
372 count
-= (1<<inode
->i_blkbits
);
374 bh
->b_end_io
= end_bitmap_write
;
375 bh
->b_private
= bitmap
;
376 atomic_inc(&bitmap
->pending_writes
);
377 set_buffer_locked(bh
);
378 set_buffer_mapped(bh
);
382 bh
= bh
->b_this_page
;
386 wait_event(bitmap
->write_wait
,
387 atomic_read(&bitmap
->pending_writes
)==0);
388 if (bitmap
->flags
& BITMAP_WRITE_ERROR
)
392 printk(KERN_ALERT
"md: bitmap read error: (%dB @ %llu): %d\n",
394 (unsigned long long)index
<< PAGE_SHIFT
,
400 * bitmap file superblock operations
403 /* update the event counter and sync the superblock to disk */
404 void bitmap_update_sb(struct bitmap
*bitmap
)
408 if (!bitmap
|| !bitmap
->mddev
) /* no bitmap for this array */
410 if (bitmap
->mddev
->bitmap_info
.external
)
412 if (!bitmap
->storage
.sb_page
) /* no superblock */
414 sb
= kmap_atomic(bitmap
->storage
.sb_page
);
415 sb
->events
= cpu_to_le64(bitmap
->mddev
->events
);
416 if (bitmap
->mddev
->events
< bitmap
->events_cleared
)
417 /* rocking back to read-only */
418 bitmap
->events_cleared
= bitmap
->mddev
->events
;
419 sb
->events_cleared
= cpu_to_le64(bitmap
->events_cleared
);
420 sb
->state
= cpu_to_le32(bitmap
->flags
);
421 /* Just in case these have been changed via sysfs: */
422 sb
->daemon_sleep
= cpu_to_le32(bitmap
->mddev
->bitmap_info
.daemon_sleep
/HZ
);
423 sb
->write_behind
= cpu_to_le32(bitmap
->mddev
->bitmap_info
.max_write_behind
);
425 write_page(bitmap
, bitmap
->storage
.sb_page
, 1);
428 /* print out the bitmap file superblock */
429 void bitmap_print_sb(struct bitmap
*bitmap
)
433 if (!bitmap
|| !bitmap
->storage
.sb_page
)
435 sb
= kmap_atomic(bitmap
->storage
.sb_page
);
436 printk(KERN_DEBUG
"%s: bitmap file superblock:\n", bmname(bitmap
));
437 printk(KERN_DEBUG
" magic: %08x\n", le32_to_cpu(sb
->magic
));
438 printk(KERN_DEBUG
" version: %d\n", le32_to_cpu(sb
->version
));
439 printk(KERN_DEBUG
" uuid: %08x.%08x.%08x.%08x\n",
440 *(__u32
*)(sb
->uuid
+0),
441 *(__u32
*)(sb
->uuid
+4),
442 *(__u32
*)(sb
->uuid
+8),
443 *(__u32
*)(sb
->uuid
+12));
444 printk(KERN_DEBUG
" events: %llu\n",
445 (unsigned long long) le64_to_cpu(sb
->events
));
446 printk(KERN_DEBUG
"events cleared: %llu\n",
447 (unsigned long long) le64_to_cpu(sb
->events_cleared
));
448 printk(KERN_DEBUG
" state: %08x\n", le32_to_cpu(sb
->state
));
449 printk(KERN_DEBUG
" chunksize: %d B\n", le32_to_cpu(sb
->chunksize
));
450 printk(KERN_DEBUG
" daemon sleep: %ds\n", le32_to_cpu(sb
->daemon_sleep
));
451 printk(KERN_DEBUG
" sync size: %llu KB\n",
452 (unsigned long long)le64_to_cpu(sb
->sync_size
)/2);
453 printk(KERN_DEBUG
"max write behind: %d\n", le32_to_cpu(sb
->write_behind
));
461 * This function is somewhat the reverse of bitmap_read_sb. bitmap_read_sb
462 * reads and verifies the on-disk bitmap superblock and populates bitmap_info.
463 * This function verifies 'bitmap_info' and populates the on-disk bitmap
464 * structure, which is to be written to disk.
466 * Returns: 0 on success, -Exxx on error
468 static int bitmap_new_disk_sb(struct bitmap
*bitmap
)
471 unsigned long chunksize
, daemon_sleep
, write_behind
;
474 bitmap
->storage
.sb_page
= alloc_page(GFP_KERNEL
);
475 if (IS_ERR(bitmap
->storage
.sb_page
)) {
476 err
= PTR_ERR(bitmap
->storage
.sb_page
);
477 bitmap
->storage
.sb_page
= NULL
;
480 bitmap
->storage
.sb_page
->index
= 0;
482 sb
= kmap_atomic(bitmap
->storage
.sb_page
);
484 sb
->magic
= cpu_to_le32(BITMAP_MAGIC
);
485 sb
->version
= cpu_to_le32(BITMAP_MAJOR_HI
);
487 chunksize
= bitmap
->mddev
->bitmap_info
.chunksize
;
489 if (!is_power_of_2(chunksize
)) {
491 printk(KERN_ERR
"bitmap chunksize not a power of 2\n");
494 sb
->chunksize
= cpu_to_le32(chunksize
);
496 daemon_sleep
= bitmap
->mddev
->bitmap_info
.daemon_sleep
;
498 (daemon_sleep
< 1) || (daemon_sleep
> MAX_SCHEDULE_TIMEOUT
)) {
499 printk(KERN_INFO
"Choosing daemon_sleep default (5 sec)\n");
500 daemon_sleep
= 5 * HZ
;
502 sb
->daemon_sleep
= cpu_to_le32(daemon_sleep
);
503 bitmap
->mddev
->bitmap_info
.daemon_sleep
= daemon_sleep
;
506 * FIXME: write_behind for RAID1. If not specified, what
507 * is a good choice? We choose COUNTER_MAX / 2 arbitrarily.
509 write_behind
= bitmap
->mddev
->bitmap_info
.max_write_behind
;
510 if (write_behind
> COUNTER_MAX
)
511 write_behind
= COUNTER_MAX
/ 2;
512 sb
->write_behind
= cpu_to_le32(write_behind
);
513 bitmap
->mddev
->bitmap_info
.max_write_behind
= write_behind
;
515 /* keep the array size field of the bitmap superblock up to date */
516 sb
->sync_size
= cpu_to_le64(bitmap
->mddev
->resync_max_sectors
);
518 memcpy(sb
->uuid
, bitmap
->mddev
->uuid
, 16);
520 bitmap
->flags
|= BITMAP_STALE
;
521 sb
->state
|= cpu_to_le32(BITMAP_STALE
);
522 bitmap
->events_cleared
= bitmap
->mddev
->events
;
523 sb
->events_cleared
= cpu_to_le64(bitmap
->mddev
->events
);
530 /* read the superblock from the bitmap file and initialize some bitmap fields */
531 static int bitmap_read_sb(struct bitmap
*bitmap
)
535 unsigned long chunksize
, daemon_sleep
, write_behind
;
536 unsigned long long events
;
538 struct page
*sb_page
;
540 if (!bitmap
->storage
.file
&& !bitmap
->mddev
->bitmap_info
.offset
) {
541 chunksize
= 128 * 1024 * 1024;
542 daemon_sleep
= 5 * HZ
;
544 bitmap
->flags
= BITMAP_STALE
;
548 /* page 0 is the superblock, read it... */
549 sb_page
= alloc_page(GFP_KERNEL
);
552 bitmap
->storage
.sb_page
= sb_page
;
554 if (bitmap
->storage
.file
) {
555 loff_t isize
= i_size_read(bitmap
->storage
.file
->f_mapping
->host
);
556 int bytes
= isize
> PAGE_SIZE
? PAGE_SIZE
: isize
;
558 err
= read_page(bitmap
->storage
.file
, 0,
559 bitmap
, bytes
, sb_page
);
561 err
= read_sb_page(bitmap
->mddev
,
562 bitmap
->mddev
->bitmap_info
.offset
,
564 0, sizeof(bitmap_super_t
));
569 sb
= kmap_atomic(sb_page
);
571 chunksize
= le32_to_cpu(sb
->chunksize
);
572 daemon_sleep
= le32_to_cpu(sb
->daemon_sleep
) * HZ
;
573 write_behind
= le32_to_cpu(sb
->write_behind
);
575 /* verify that the bitmap-specific fields are valid */
576 if (sb
->magic
!= cpu_to_le32(BITMAP_MAGIC
))
577 reason
= "bad magic";
578 else if (le32_to_cpu(sb
->version
) < BITMAP_MAJOR_LO
||
579 le32_to_cpu(sb
->version
) > BITMAP_MAJOR_HI
)
580 reason
= "unrecognized superblock version";
581 else if (chunksize
< 512)
582 reason
= "bitmap chunksize too small";
583 else if (!is_power_of_2(chunksize
))
584 reason
= "bitmap chunksize not a power of 2";
585 else if (daemon_sleep
< 1 || daemon_sleep
> MAX_SCHEDULE_TIMEOUT
)
586 reason
= "daemon sleep period out of range";
587 else if (write_behind
> COUNTER_MAX
)
588 reason
= "write-behind limit out of range (0 - 16383)";
590 printk(KERN_INFO
"%s: invalid bitmap file superblock: %s\n",
591 bmname(bitmap
), reason
);
595 /* keep the array size field of the bitmap superblock up to date */
596 sb
->sync_size
= cpu_to_le64(bitmap
->mddev
->resync_max_sectors
);
598 if (bitmap
->mddev
->persistent
) {
600 * We have a persistent array superblock, so compare the
601 * bitmap's UUID and event counter to the mddev's
603 if (memcmp(sb
->uuid
, bitmap
->mddev
->uuid
, 16)) {
605 "%s: bitmap superblock UUID mismatch\n",
609 events
= le64_to_cpu(sb
->events
);
610 if (events
< bitmap
->mddev
->events
) {
612 "%s: bitmap file is out of date (%llu < %llu) "
613 "-- forcing full recovery\n",
614 bmname(bitmap
), events
,
615 (unsigned long long) bitmap
->mddev
->events
);
616 sb
->state
|= cpu_to_le32(BITMAP_STALE
);
620 /* assign fields using values from superblock */
621 bitmap
->flags
|= le32_to_cpu(sb
->state
);
622 if (le32_to_cpu(sb
->version
) == BITMAP_MAJOR_HOSTENDIAN
)
623 bitmap
->flags
|= BITMAP_HOSTENDIAN
;
624 bitmap
->events_cleared
= le64_to_cpu(sb
->events_cleared
);
629 if (bitmap
->flags
& BITMAP_STALE
)
630 bitmap
->events_cleared
= bitmap
->mddev
->events
;
631 bitmap
->mddev
->bitmap_info
.chunksize
= chunksize
;
632 bitmap
->mddev
->bitmap_info
.daemon_sleep
= daemon_sleep
;
633 bitmap
->mddev
->bitmap_info
.max_write_behind
= write_behind
;
635 bitmap_print_sb(bitmap
);
639 enum bitmap_mask_op
{
644 /* record the state of the bitmap in the superblock. Return the old value */
645 static int bitmap_mask_state(struct bitmap
*bitmap
, enum bitmap_state bits
,
646 enum bitmap_mask_op op
)
651 if (!bitmap
->storage
.sb_page
) /* can't set the state */
653 sb
= kmap_atomic(bitmap
->storage
.sb_page
);
654 old
= le32_to_cpu(sb
->state
) & bits
;
657 sb
->state
|= cpu_to_le32(bits
);
658 bitmap
->flags
|= bits
;
661 sb
->state
&= cpu_to_le32(~bits
);
662 bitmap
->flags
&= ~bits
;
672 * general bitmap file operations
678 * Use one bit per "chunk" (block set). We do the disk I/O on the bitmap
679 * file a page at a time. There's a superblock at the start of the file.
681 /* calculate the index of the page that contains this bit */
682 static inline unsigned long file_page_index(struct bitmap_storage
*store
,
686 chunk
+= sizeof(bitmap_super_t
) << 3;
687 return chunk
>> PAGE_BIT_SHIFT
;
690 /* calculate the (bit) offset of this bit within a page */
691 static inline unsigned long file_page_offset(struct bitmap_storage
*store
,
695 chunk
+= sizeof(bitmap_super_t
) << 3;
696 return chunk
& (PAGE_BITS
- 1);
700 * return a pointer to the page in the filemap that contains the given bit
702 * this lookup is complicated by the fact that the bitmap sb might be exactly
703 * 1 page (e.g., x86) or less than 1 page -- so the bitmap might start on page
706 static inline struct page
*filemap_get_page(struct bitmap_storage
*store
,
709 if (file_page_index(store
, chunk
) >= store
->file_pages
)
711 return store
->filemap
[file_page_index(store
, chunk
)
712 - file_page_index(store
, 0)];
715 static void bitmap_file_unmap(struct bitmap
*bitmap
)
717 struct page
**map
, *sb_page
;
721 struct bitmap_storage
*store
= &bitmap
->storage
;
723 spin_lock_irqsave(&bitmap
->lock
, flags
);
724 map
= store
->filemap
;
725 store
->filemap
= NULL
;
726 attr
= store
->filemap_attr
;
727 store
->filemap_attr
= NULL
;
728 pages
= store
->file_pages
;
729 store
->file_pages
= 0;
730 sb_page
= store
->sb_page
;
731 store
->sb_page
= NULL
;
732 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
735 if (map
[pages
] != sb_page
) /* 0 is sb_page, release it below */
736 free_buffers(map
[pages
]);
741 free_buffers(sb_page
);
744 static void bitmap_file_put(struct bitmap
*bitmap
)
749 spin_lock_irqsave(&bitmap
->lock
, flags
);
750 file
= bitmap
->storage
.file
;
751 bitmap
->storage
.file
= NULL
;
752 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
755 wait_event(bitmap
->write_wait
,
756 atomic_read(&bitmap
->pending_writes
)==0);
757 bitmap_file_unmap(bitmap
);
760 struct inode
*inode
= file
->f_path
.dentry
->d_inode
;
761 invalidate_mapping_pages(inode
->i_mapping
, 0, -1);
767 * bitmap_file_kick - if an error occurs while manipulating the bitmap file
768 * then it is no longer reliable, so we stop using it and we mark the file
769 * as failed in the superblock
771 static void bitmap_file_kick(struct bitmap
*bitmap
)
773 char *path
, *ptr
= NULL
;
775 if (bitmap_mask_state(bitmap
, BITMAP_STALE
, MASK_SET
) == 0) {
776 bitmap_update_sb(bitmap
);
778 if (bitmap
->storage
.file
) {
779 path
= kmalloc(PAGE_SIZE
, GFP_KERNEL
);
781 ptr
= d_path(&bitmap
->storage
.file
->f_path
,
785 "%s: kicking failed bitmap file %s from array!\n",
786 bmname(bitmap
), IS_ERR(ptr
) ? "" : ptr
);
791 "%s: disabling internal bitmap due to errors\n",
795 bitmap_file_put(bitmap
);
800 enum bitmap_page_attr
{
801 BITMAP_PAGE_DIRTY
= 0, /* there are set bits that need to be synced */
802 BITMAP_PAGE_PENDING
= 1, /* there are bits that are being cleaned.
803 * i.e. counter is 1 or 2. */
804 BITMAP_PAGE_NEEDWRITE
= 2, /* there are cleared bits that need to be synced */
807 static inline void set_page_attr(struct bitmap
*bitmap
, int pnum
,
808 enum bitmap_page_attr attr
)
810 __set_bit((pnum
<<2) + attr
, bitmap
->storage
.filemap_attr
);
813 static inline void clear_page_attr(struct bitmap
*bitmap
, int pnum
,
814 enum bitmap_page_attr attr
)
816 __clear_bit((pnum
<<2) + attr
, bitmap
->storage
.filemap_attr
);
819 static inline unsigned long test_page_attr(struct bitmap
*bitmap
, int pnum
,
820 enum bitmap_page_attr attr
)
822 return test_bit((pnum
<<2) + attr
, bitmap
->storage
.filemap_attr
);
826 * bitmap_file_set_bit -- called before performing a write to the md device
827 * to set (and eventually sync) a particular bit in the bitmap file
829 * we set the bit immediately, then we record the page number so that
830 * when an unplug occurs, we can flush the dirty pages out to disk
832 static void bitmap_file_set_bit(struct bitmap
*bitmap
, sector_t block
)
837 unsigned long chunk
= block
>> bitmap
->chunkshift
;
839 page
= filemap_get_page(&bitmap
->storage
, chunk
);
842 bit
= file_page_offset(&bitmap
->storage
, chunk
);
845 kaddr
= kmap_atomic(page
);
846 if (bitmap
->flags
& BITMAP_HOSTENDIAN
)
849 __set_bit_le(bit
, kaddr
);
850 kunmap_atomic(kaddr
);
851 pr_debug("set file bit %lu page %lu\n", bit
, page
->index
);
852 /* record page number so it gets flushed to disk when unplug occurs */
853 set_page_attr(bitmap
, page
->index
, BITMAP_PAGE_DIRTY
);
856 static void bitmap_file_clear_bit(struct bitmap
*bitmap
, sector_t block
)
861 unsigned long chunk
= block
>> bitmap
->chunkshift
;
863 page
= filemap_get_page(&bitmap
->storage
, chunk
);
866 bit
= file_page_offset(&bitmap
->storage
, chunk
);
867 paddr
= kmap_atomic(page
);
868 if (bitmap
->flags
& BITMAP_HOSTENDIAN
)
869 clear_bit(bit
, paddr
);
871 __clear_bit_le(bit
, paddr
);
872 kunmap_atomic(paddr
);
873 if (!test_page_attr(bitmap
, page
->index
, BITMAP_PAGE_NEEDWRITE
)) {
874 set_page_attr(bitmap
, page
->index
, BITMAP_PAGE_PENDING
);
875 bitmap
->allclean
= 0;
879 /* this gets called when the md device is ready to unplug its underlying
880 * (slave) device queues -- before we let any writes go down, we need to
881 * sync the dirty pages of the bitmap file to disk */
882 void bitmap_unplug(struct bitmap
*bitmap
)
884 unsigned long i
, flags
;
885 int dirty
, need_write
;
888 if (!bitmap
|| !bitmap
->storage
.filemap
)
891 /* look at each page to see if there are any set bits that need to be
892 * flushed out to disk */
893 for (i
= 0; i
< bitmap
->storage
.file_pages
; i
++) {
894 spin_lock_irqsave(&bitmap
->lock
, flags
);
895 if (!bitmap
->storage
.filemap
) {
896 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
899 dirty
= test_page_attr(bitmap
, i
, BITMAP_PAGE_DIRTY
);
900 need_write
= test_page_attr(bitmap
, i
, BITMAP_PAGE_NEEDWRITE
);
901 clear_page_attr(bitmap
, i
, BITMAP_PAGE_DIRTY
);
902 clear_page_attr(bitmap
, i
, BITMAP_PAGE_NEEDWRITE
);
903 if (dirty
|| need_write
)
904 clear_page_attr(bitmap
, i
, BITMAP_PAGE_PENDING
);
907 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
909 if (dirty
|| need_write
)
910 write_page(bitmap
, bitmap
->storage
.filemap
[i
], 0);
912 if (wait
) { /* if any writes were performed, we need to wait on them */
913 if (bitmap
->storage
.file
)
914 wait_event(bitmap
->write_wait
,
915 atomic_read(&bitmap
->pending_writes
)==0);
917 md_super_wait(bitmap
->mddev
);
919 if (bitmap
->flags
& BITMAP_WRITE_ERROR
)
920 bitmap_file_kick(bitmap
);
922 EXPORT_SYMBOL(bitmap_unplug
);
924 static void bitmap_set_memory_bits(struct bitmap
*bitmap
, sector_t offset
, int needed
);
925 /* * bitmap_init_from_disk -- called at bitmap_create time to initialize
926 * the in-memory bitmap from the on-disk bitmap -- also, sets up the
927 * memory mapping of the bitmap file
929 * if there's no bitmap file, or if the bitmap file had been
930 * previously kicked from the array, we mark all the bits as
931 * 1's in order to cause a full resync.
933 * We ignore all bits for sectors that end earlier than 'start'.
934 * This is used when reading an out-of-date bitmap...
936 static int bitmap_init_from_disk(struct bitmap
*bitmap
, sector_t start
)
938 unsigned long i
, chunks
, index
, oldindex
, bit
;
940 struct page
*page
= NULL
;
941 unsigned long num_pages
, bit_cnt
= 0;
943 unsigned long bytes
, offset
;
947 struct bitmap_storage
*store
= &bitmap
->storage
;
949 chunks
= bitmap
->chunks
;
952 if (!file
&& !bitmap
->mddev
->bitmap_info
.offset
) {
953 /* No permanent bitmap - fill with '1s'. */
954 store
->filemap
= NULL
;
955 store
->file_pages
= 0;
956 for (i
= 0; i
< chunks
; i
++) {
957 /* if the disk bit is set, set the memory bit */
958 int needed
= ((sector_t
)(i
+1) << (bitmap
->chunkshift
)
960 bitmap_set_memory_bits(bitmap
,
961 (sector_t
)i
<< bitmap
->chunkshift
,
967 outofdate
= bitmap
->flags
& BITMAP_STALE
;
969 printk(KERN_INFO
"%s: bitmap file is out of date, doing full "
970 "recovery\n", bmname(bitmap
));
972 bytes
= DIV_ROUND_UP(bitmap
->chunks
, 8);
973 if (!bitmap
->mddev
->bitmap_info
.external
)
974 bytes
+= sizeof(bitmap_super_t
);
976 num_pages
= DIV_ROUND_UP(bytes
, PAGE_SIZE
);
978 if (file
&& i_size_read(file
->f_mapping
->host
) < bytes
) {
979 printk(KERN_INFO
"%s: bitmap file too short %lu < %lu\n",
981 (unsigned long) i_size_read(file
->f_mapping
->host
),
988 store
->filemap
= kmalloc(sizeof(struct page
*)
989 * num_pages
, GFP_KERNEL
);
995 if (store
->sb_page
) {
996 store
->filemap
[0] = store
->sb_page
;
998 offset
= sizeof(bitmap_super_t
);
1000 for ( ; pnum
< num_pages
; pnum
++) {
1001 store
->filemap
[pnum
] = alloc_page(GFP_KERNEL
);
1002 if (!store
->filemap
[pnum
]) {
1003 store
->file_pages
= pnum
;
1007 store
->file_pages
= pnum
;
1009 /* We need 4 bits per page, rounded up to a multiple of sizeof(unsigned long) */
1010 store
->filemap_attr
= kzalloc(
1011 roundup(DIV_ROUND_UP(num_pages
*4, 8), sizeof(unsigned long)),
1013 if (!store
->filemap_attr
)
1018 for (i
= 0; i
< chunks
; i
++) {
1020 index
= file_page_index(&bitmap
->storage
, i
);
1021 bit
= file_page_offset(&bitmap
->storage
, i
);
1022 if (index
!= oldindex
) { /* this is a new page, read it in */
1024 /* unmap the old page, we're done with it */
1025 if (index
== num_pages
-1)
1026 count
= bytes
- index
* PAGE_SIZE
;
1029 page
= store
->filemap
[index
];
1031 ret
= read_page(file
, index
, bitmap
,
1036 bitmap
->mddev
->bitmap_info
.offset
,
1045 store
->last_page_size
= count
;
1049 * if bitmap is out of date, dirty the
1050 * whole page and write it out
1052 paddr
= kmap_atomic(page
);
1053 memset(paddr
+ offset
, 0xff,
1054 PAGE_SIZE
- offset
);
1055 kunmap_atomic(paddr
);
1056 write_page(bitmap
, page
, 1);
1059 if (bitmap
->flags
& BITMAP_WRITE_ERROR
)
1063 paddr
= kmap_atomic(page
);
1064 if (bitmap
->flags
& BITMAP_HOSTENDIAN
)
1065 b
= test_bit(bit
, paddr
);
1067 b
= test_bit_le(bit
, paddr
);
1068 kunmap_atomic(paddr
);
1070 /* if the disk bit is set, set the memory bit */
1071 int needed
= ((sector_t
)(i
+1) << bitmap
->chunkshift
1073 bitmap_set_memory_bits(bitmap
,
1074 (sector_t
)i
<< bitmap
->chunkshift
,
1081 printk(KERN_INFO
"%s: bitmap initialized from disk: "
1082 "read %lu/%lu pages, set %lu of %lu bits\n",
1083 bmname(bitmap
), store
->file_pages
,
1084 num_pages
, bit_cnt
, chunks
);
1089 printk(KERN_INFO
"%s: bitmap initialisation failed: %d\n",
1090 bmname(bitmap
), ret
);
1094 void bitmap_write_all(struct bitmap
*bitmap
)
1096 /* We don't actually write all bitmap blocks here,
1097 * just flag them as needing to be written
1101 if (!bitmap
|| !bitmap
->storage
.filemap
)
1103 if (bitmap
->storage
.file
)
1104 /* Only one copy, so nothing needed */
1107 spin_lock_irq(&bitmap
->lock
);
1108 for (i
= 0; i
< bitmap
->storage
.file_pages
; i
++)
1109 set_page_attr(bitmap
, i
,
1110 BITMAP_PAGE_NEEDWRITE
);
1111 bitmap
->allclean
= 0;
1112 spin_unlock_irq(&bitmap
->lock
);
1115 static void bitmap_count_page(struct bitmap
*bitmap
, sector_t offset
, int inc
)
1117 sector_t chunk
= offset
>> bitmap
->chunkshift
;
1118 unsigned long page
= chunk
>> PAGE_COUNTER_SHIFT
;
1119 bitmap
->bp
[page
].count
+= inc
;
1120 bitmap_checkfree(bitmap
, page
);
1123 static void bitmap_set_pending(struct bitmap
*bitmap
, sector_t offset
)
1125 sector_t chunk
= offset
>> bitmap
->chunkshift
;
1126 unsigned long page
= chunk
>> PAGE_COUNTER_SHIFT
;
1127 struct bitmap_page
*bp
= &bitmap
->bp
[page
];
1133 static bitmap_counter_t
*bitmap_get_counter(struct bitmap
*bitmap
,
1134 sector_t offset
, sector_t
*blocks
,
1138 * bitmap daemon -- periodically wakes up to clean bits and flush pages
1142 void bitmap_daemon_work(struct mddev
*mddev
)
1144 struct bitmap
*bitmap
;
1146 unsigned long nextpage
;
1147 unsigned long flags
;
1150 /* Use a mutex to guard daemon_work against
1153 mutex_lock(&mddev
->bitmap_info
.mutex
);
1154 bitmap
= mddev
->bitmap
;
1155 if (bitmap
== NULL
) {
1156 mutex_unlock(&mddev
->bitmap_info
.mutex
);
1159 if (time_before(jiffies
, bitmap
->daemon_lastrun
1160 + mddev
->bitmap_info
.daemon_sleep
))
1163 bitmap
->daemon_lastrun
= jiffies
;
1164 if (bitmap
->allclean
) {
1165 mddev
->thread
->timeout
= MAX_SCHEDULE_TIMEOUT
;
1168 bitmap
->allclean
= 1;
1170 /* Any file-page which is PENDING now needs to be written.
1171 * So set NEEDWRITE now, then after we make any last-minute changes
1174 spin_lock_irqsave(&bitmap
->lock
, flags
);
1175 for (j
= 0; j
< bitmap
->storage
.file_pages
; j
++)
1176 if (test_page_attr(bitmap
, j
,
1177 BITMAP_PAGE_PENDING
)) {
1178 set_page_attr(bitmap
, j
,
1179 BITMAP_PAGE_NEEDWRITE
);
1180 clear_page_attr(bitmap
, j
,
1181 BITMAP_PAGE_PENDING
);
1184 if (bitmap
->need_sync
&&
1185 mddev
->bitmap_info
.external
== 0) {
1186 /* Arrange for superblock update as well as
1189 bitmap
->need_sync
= 0;
1190 if (bitmap
->storage
.filemap
) {
1191 sb
= kmap_atomic(bitmap
->storage
.sb_page
);
1192 sb
->events_cleared
=
1193 cpu_to_le64(bitmap
->events_cleared
);
1195 set_page_attr(bitmap
, 0,
1196 BITMAP_PAGE_NEEDWRITE
);
1199 /* Now look at the bitmap counters and if any are '2' or '1',
1200 * decrement and handle accordingly.
1203 for (j
= 0; j
< bitmap
->chunks
; j
++) {
1204 bitmap_counter_t
*bmc
;
1205 sector_t block
= (sector_t
)j
<< bitmap
->chunkshift
;
1207 if (j
== nextpage
) {
1208 nextpage
+= PAGE_COUNTER_RATIO
;
1209 if (!bitmap
->bp
[j
>> PAGE_COUNTER_SHIFT
].pending
) {
1210 j
|= PAGE_COUNTER_MASK
;
1213 bitmap
->bp
[j
>> PAGE_COUNTER_SHIFT
].pending
= 0;
1215 bmc
= bitmap_get_counter(bitmap
,
1220 j
|= PAGE_COUNTER_MASK
;
1223 if (*bmc
== 1 && !bitmap
->need_sync
) {
1224 /* We can clear the bit */
1226 bitmap_count_page(bitmap
, block
, -1);
1227 bitmap_file_clear_bit(bitmap
, block
);
1228 } else if (*bmc
&& *bmc
<= 2) {
1230 bitmap_set_pending(bitmap
, block
);
1231 bitmap
->allclean
= 0;
1235 /* Now start writeout on any page in NEEDWRITE that isn't DIRTY.
1236 * DIRTY pages need to be written by bitmap_unplug so it can wait
1238 * If we find any DIRTY page we stop there and let bitmap_unplug
1239 * handle all the rest. This is important in the case where
1240 * the first blocking holds the superblock and it has been updated.
1241 * We mustn't write any other blocks before the superblock.
1243 for (j
= 0; j
< bitmap
->storage
.file_pages
; j
++) {
1245 if (test_page_attr(bitmap
, j
,
1247 /* bitmap_unplug will handle the rest */
1249 if (test_page_attr(bitmap
, j
,
1250 BITMAP_PAGE_NEEDWRITE
)) {
1251 clear_page_attr(bitmap
, j
,
1252 BITMAP_PAGE_NEEDWRITE
);
1253 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
1254 write_page(bitmap
, bitmap
->storage
.filemap
[j
], 0);
1255 spin_lock_irqsave(&bitmap
->lock
, flags
);
1256 if (!bitmap
->storage
.filemap
)
1260 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
1263 if (bitmap
->allclean
== 0)
1264 mddev
->thread
->timeout
=
1265 mddev
->bitmap_info
.daemon_sleep
;
1266 mutex_unlock(&mddev
->bitmap_info
.mutex
);
1269 static bitmap_counter_t
*bitmap_get_counter(struct bitmap
*bitmap
,
1270 sector_t offset
, sector_t
*blocks
,
1272 __releases(bitmap
->lock
)
1273 __acquires(bitmap
->lock
)
1275 /* If 'create', we might release the lock and reclaim it.
1276 * The lock must have been taken with interrupts enabled.
1277 * If !create, we don't release the lock.
1279 sector_t chunk
= offset
>> bitmap
->chunkshift
;
1280 unsigned long page
= chunk
>> PAGE_COUNTER_SHIFT
;
1281 unsigned long pageoff
= (chunk
& PAGE_COUNTER_MASK
) << COUNTER_BYTE_SHIFT
;
1285 err
= bitmap_checkpage(bitmap
, page
, create
);
1287 if (bitmap
->bp
[page
].hijacked
||
1288 bitmap
->bp
[page
].map
== NULL
)
1289 csize
= ((sector_t
)1) << (bitmap
->chunkshift
+
1290 PAGE_COUNTER_SHIFT
- 1);
1292 csize
= ((sector_t
)1) << bitmap
->chunkshift
;
1293 *blocks
= csize
- (offset
& (csize
- 1));
1298 /* now locked ... */
1300 if (bitmap
->bp
[page
].hijacked
) { /* hijacked pointer */
1301 /* should we use the first or second counter field
1302 * of the hijacked pointer? */
1303 int hi
= (pageoff
> PAGE_COUNTER_MASK
);
1304 return &((bitmap_counter_t
*)
1305 &bitmap
->bp
[page
].map
)[hi
];
1306 } else /* page is allocated */
1307 return (bitmap_counter_t
*)
1308 &(bitmap
->bp
[page
].map
[pageoff
]);
1311 int bitmap_startwrite(struct bitmap
*bitmap
, sector_t offset
, unsigned long sectors
, int behind
)
1318 atomic_inc(&bitmap
->behind_writes
);
1319 bw
= atomic_read(&bitmap
->behind_writes
);
1320 if (bw
> bitmap
->behind_writes_used
)
1321 bitmap
->behind_writes_used
= bw
;
1323 pr_debug("inc write-behind count %d/%lu\n",
1324 bw
, bitmap
->mddev
->bitmap_info
.max_write_behind
);
1329 bitmap_counter_t
*bmc
;
1331 spin_lock_irq(&bitmap
->lock
);
1332 bmc
= bitmap_get_counter(bitmap
, offset
, &blocks
, 1);
1334 spin_unlock_irq(&bitmap
->lock
);
1338 if (unlikely(COUNTER(*bmc
) == COUNTER_MAX
)) {
1339 DEFINE_WAIT(__wait
);
1340 /* note that it is safe to do the prepare_to_wait
1341 * after the test as long as we do it before dropping
1344 prepare_to_wait(&bitmap
->overflow_wait
, &__wait
,
1345 TASK_UNINTERRUPTIBLE
);
1346 spin_unlock_irq(&bitmap
->lock
);
1348 finish_wait(&bitmap
->overflow_wait
, &__wait
);
1354 bitmap_file_set_bit(bitmap
, offset
);
1355 bitmap_count_page(bitmap
, offset
, 1);
1363 spin_unlock_irq(&bitmap
->lock
);
1366 if (sectors
> blocks
)
1373 EXPORT_SYMBOL(bitmap_startwrite
);
1375 void bitmap_endwrite(struct bitmap
*bitmap
, sector_t offset
, unsigned long sectors
,
1376 int success
, int behind
)
1381 if (atomic_dec_and_test(&bitmap
->behind_writes
))
1382 wake_up(&bitmap
->behind_wait
);
1383 pr_debug("dec write-behind count %d/%lu\n",
1384 atomic_read(&bitmap
->behind_writes
),
1385 bitmap
->mddev
->bitmap_info
.max_write_behind
);
1390 unsigned long flags
;
1391 bitmap_counter_t
*bmc
;
1393 spin_lock_irqsave(&bitmap
->lock
, flags
);
1394 bmc
= bitmap_get_counter(bitmap
, offset
, &blocks
, 0);
1396 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
1400 if (success
&& !bitmap
->mddev
->degraded
&&
1401 bitmap
->events_cleared
< bitmap
->mddev
->events
) {
1402 bitmap
->events_cleared
= bitmap
->mddev
->events
;
1403 bitmap
->need_sync
= 1;
1404 sysfs_notify_dirent_safe(bitmap
->sysfs_can_clear
);
1407 if (!success
&& !NEEDED(*bmc
))
1408 *bmc
|= NEEDED_MASK
;
1410 if (COUNTER(*bmc
) == COUNTER_MAX
)
1411 wake_up(&bitmap
->overflow_wait
);
1415 bitmap_set_pending(bitmap
, offset
);
1416 bitmap
->allclean
= 0;
1418 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
1420 if (sectors
> blocks
)
1426 EXPORT_SYMBOL(bitmap_endwrite
);
1428 static int __bitmap_start_sync(struct bitmap
*bitmap
, sector_t offset
, sector_t
*blocks
,
1431 bitmap_counter_t
*bmc
;
1433 if (bitmap
== NULL
) {/* FIXME or bitmap set as 'failed' */
1435 return 1; /* always resync if no bitmap */
1437 spin_lock_irq(&bitmap
->lock
);
1438 bmc
= bitmap_get_counter(bitmap
, offset
, blocks
, 0);
1444 else if (NEEDED(*bmc
)) {
1446 if (!degraded
) { /* don't set/clear bits if degraded */
1447 *bmc
|= RESYNC_MASK
;
1448 *bmc
&= ~NEEDED_MASK
;
1452 spin_unlock_irq(&bitmap
->lock
);
1456 int bitmap_start_sync(struct bitmap
*bitmap
, sector_t offset
, sector_t
*blocks
,
1459 /* bitmap_start_sync must always report on multiples of whole
1460 * pages, otherwise resync (which is very PAGE_SIZE based) will
1462 * So call __bitmap_start_sync repeatedly (if needed) until
1463 * At least PAGE_SIZE>>9 blocks are covered.
1464 * Return the 'or' of the result.
1470 while (*blocks
< (PAGE_SIZE
>>9)) {
1471 rv
|= __bitmap_start_sync(bitmap
, offset
,
1472 &blocks1
, degraded
);
1478 EXPORT_SYMBOL(bitmap_start_sync
);
1480 void bitmap_end_sync(struct bitmap
*bitmap
, sector_t offset
, sector_t
*blocks
, int aborted
)
1482 bitmap_counter_t
*bmc
;
1483 unsigned long flags
;
1485 if (bitmap
== NULL
) {
1489 spin_lock_irqsave(&bitmap
->lock
, flags
);
1490 bmc
= bitmap_get_counter(bitmap
, offset
, blocks
, 0);
1495 *bmc
&= ~RESYNC_MASK
;
1497 if (!NEEDED(*bmc
) && aborted
)
1498 *bmc
|= NEEDED_MASK
;
1501 bitmap_set_pending(bitmap
, offset
);
1502 bitmap
->allclean
= 0;
1507 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
1509 EXPORT_SYMBOL(bitmap_end_sync
);
1511 void bitmap_close_sync(struct bitmap
*bitmap
)
1513 /* Sync has finished, and any bitmap chunks that weren't synced
1514 * properly have been aborted. It remains to us to clear the
1515 * RESYNC bit wherever it is still on
1517 sector_t sector
= 0;
1521 while (sector
< bitmap
->mddev
->resync_max_sectors
) {
1522 bitmap_end_sync(bitmap
, sector
, &blocks
, 0);
1526 EXPORT_SYMBOL(bitmap_close_sync
);
1528 void bitmap_cond_end_sync(struct bitmap
*bitmap
, sector_t sector
)
1536 bitmap
->last_end_sync
= jiffies
;
1539 if (time_before(jiffies
, (bitmap
->last_end_sync
1540 + bitmap
->mddev
->bitmap_info
.daemon_sleep
)))
1542 wait_event(bitmap
->mddev
->recovery_wait
,
1543 atomic_read(&bitmap
->mddev
->recovery_active
) == 0);
1545 bitmap
->mddev
->curr_resync_completed
= sector
;
1546 set_bit(MD_CHANGE_CLEAN
, &bitmap
->mddev
->flags
);
1547 sector
&= ~((1ULL << bitmap
->chunkshift
) - 1);
1549 while (s
< sector
&& s
< bitmap
->mddev
->resync_max_sectors
) {
1550 bitmap_end_sync(bitmap
, s
, &blocks
, 0);
1553 bitmap
->last_end_sync
= jiffies
;
1554 sysfs_notify(&bitmap
->mddev
->kobj
, NULL
, "sync_completed");
1556 EXPORT_SYMBOL(bitmap_cond_end_sync
);
1558 static void bitmap_set_memory_bits(struct bitmap
*bitmap
, sector_t offset
, int needed
)
1560 /* For each chunk covered by any of these sectors, set the
1561 * counter to 2 and possibly set resync_needed. They should all
1562 * be 0 at this point
1566 bitmap_counter_t
*bmc
;
1567 spin_lock_irq(&bitmap
->lock
);
1568 bmc
= bitmap_get_counter(bitmap
, offset
, &secs
, 1);
1570 spin_unlock_irq(&bitmap
->lock
);
1574 *bmc
= 2 | (needed
? NEEDED_MASK
: 0);
1575 bitmap_count_page(bitmap
, offset
, 1);
1576 bitmap_set_pending(bitmap
, offset
);
1577 bitmap
->allclean
= 0;
1579 spin_unlock_irq(&bitmap
->lock
);
1582 /* dirty the memory and file bits for bitmap chunks "s" to "e" */
1583 void bitmap_dirty_bits(struct bitmap
*bitmap
, unsigned long s
, unsigned long e
)
1585 unsigned long chunk
;
1587 for (chunk
= s
; chunk
<= e
; chunk
++) {
1588 sector_t sec
= (sector_t
)chunk
<< bitmap
->chunkshift
;
1589 bitmap_set_memory_bits(bitmap
, sec
, 1);
1590 spin_lock_irq(&bitmap
->lock
);
1591 bitmap_file_set_bit(bitmap
, sec
);
1592 spin_unlock_irq(&bitmap
->lock
);
1593 if (sec
< bitmap
->mddev
->recovery_cp
)
1594 /* We are asserting that the array is dirty,
1595 * so move the recovery_cp address back so
1596 * that it is obvious that it is dirty
1598 bitmap
->mddev
->recovery_cp
= sec
;
1603 * flush out any pending updates
1605 void bitmap_flush(struct mddev
*mddev
)
1607 struct bitmap
*bitmap
= mddev
->bitmap
;
1610 if (!bitmap
) /* there was no bitmap */
1613 /* run the daemon_work three time to ensure everything is flushed
1616 sleep
= mddev
->bitmap_info
.daemon_sleep
* 2;
1617 bitmap
->daemon_lastrun
-= sleep
;
1618 bitmap_daemon_work(mddev
);
1619 bitmap
->daemon_lastrun
-= sleep
;
1620 bitmap_daemon_work(mddev
);
1621 bitmap
->daemon_lastrun
-= sleep
;
1622 bitmap_daemon_work(mddev
);
1623 bitmap_update_sb(bitmap
);
1627 * free memory that was allocated
1629 static void bitmap_free(struct bitmap
*bitmap
)
1631 unsigned long k
, pages
;
1632 struct bitmap_page
*bp
;
1634 if (!bitmap
) /* there was no bitmap */
1637 /* release the bitmap file and kill the daemon */
1638 bitmap_file_put(bitmap
);
1641 pages
= bitmap
->pages
;
1643 /* free all allocated memory */
1645 if (bp
) /* deallocate the page memory */
1646 for (k
= 0; k
< pages
; k
++)
1647 if (bp
[k
].map
&& !bp
[k
].hijacked
)
1653 void bitmap_destroy(struct mddev
*mddev
)
1655 struct bitmap
*bitmap
= mddev
->bitmap
;
1657 if (!bitmap
) /* there was no bitmap */
1660 mutex_lock(&mddev
->bitmap_info
.mutex
);
1661 mddev
->bitmap
= NULL
; /* disconnect from the md device */
1662 mutex_unlock(&mddev
->bitmap_info
.mutex
);
1664 mddev
->thread
->timeout
= MAX_SCHEDULE_TIMEOUT
;
1666 if (bitmap
->sysfs_can_clear
)
1667 sysfs_put(bitmap
->sysfs_can_clear
);
1669 bitmap_free(bitmap
);
1673 * initialize the bitmap structure
1674 * if this returns an error, bitmap_destroy must be called to do clean up
1676 int bitmap_create(struct mddev
*mddev
)
1678 struct bitmap
*bitmap
;
1679 sector_t blocks
= mddev
->resync_max_sectors
;
1680 unsigned long chunks
;
1681 unsigned long pages
;
1682 struct file
*file
= mddev
->bitmap_info
.file
;
1684 struct sysfs_dirent
*bm
= NULL
;
1686 BUILD_BUG_ON(sizeof(bitmap_super_t
) != 256);
1688 BUG_ON(file
&& mddev
->bitmap_info
.offset
);
1690 bitmap
= kzalloc(sizeof(*bitmap
), GFP_KERNEL
);
1694 spin_lock_init(&bitmap
->lock
);
1695 atomic_set(&bitmap
->pending_writes
, 0);
1696 init_waitqueue_head(&bitmap
->write_wait
);
1697 init_waitqueue_head(&bitmap
->overflow_wait
);
1698 init_waitqueue_head(&bitmap
->behind_wait
);
1700 bitmap
->mddev
= mddev
;
1703 bm
= sysfs_get_dirent(mddev
->kobj
.sd
, NULL
, "bitmap");
1705 bitmap
->sysfs_can_clear
= sysfs_get_dirent(bm
, NULL
, "can_clear");
1708 bitmap
->sysfs_can_clear
= NULL
;
1710 bitmap
->storage
.file
= file
;
1713 /* As future accesses to this file will use bmap,
1714 * and bypass the page cache, we must sync the file
1719 /* read superblock from bitmap file (this sets mddev->bitmap_info.chunksize) */
1720 if (!mddev
->bitmap_info
.external
) {
1722 * If 'MD_ARRAY_FIRST_USE' is set, then device-mapper is
1723 * instructing us to create a new on-disk bitmap instance.
1725 if (test_and_clear_bit(MD_ARRAY_FIRST_USE
, &mddev
->flags
))
1726 err
= bitmap_new_disk_sb(bitmap
);
1728 err
= bitmap_read_sb(bitmap
);
1731 if (mddev
->bitmap_info
.chunksize
== 0 ||
1732 mddev
->bitmap_info
.daemon_sleep
== 0)
1733 /* chunksize and time_base need to be
1740 bitmap
->daemon_lastrun
= jiffies
;
1741 bitmap
->chunkshift
= (ffz(~mddev
->bitmap_info
.chunksize
)
1742 - BITMAP_BLOCK_SHIFT
);
1744 chunks
= (blocks
+ (1 << bitmap
->chunkshift
) - 1) >>
1746 pages
= (chunks
+ PAGE_COUNTER_RATIO
- 1) / PAGE_COUNTER_RATIO
;
1750 bitmap
->chunks
= chunks
;
1751 bitmap
->pages
= pages
;
1752 bitmap
->missing_pages
= pages
;
1754 bitmap
->bp
= kzalloc(pages
* sizeof(*bitmap
->bp
), GFP_KERNEL
);
1760 printk(KERN_INFO
"created bitmap (%lu pages) for device %s\n",
1761 pages
, bmname(bitmap
));
1763 mddev
->bitmap
= bitmap
;
1766 return (bitmap
->flags
& BITMAP_WRITE_ERROR
) ? -EIO
: 0;
1769 bitmap_free(bitmap
);
1773 int bitmap_load(struct mddev
*mddev
)
1777 sector_t sector
= 0;
1778 struct bitmap
*bitmap
= mddev
->bitmap
;
1783 /* Clear out old bitmap info first: Either there is none, or we
1784 * are resuming after someone else has possibly changed things,
1785 * so we should forget old cached info.
1786 * All chunks should be clean, but some might need_sync.
1788 while (sector
< mddev
->resync_max_sectors
) {
1790 bitmap_start_sync(bitmap
, sector
, &blocks
, 0);
1793 bitmap_close_sync(bitmap
);
1795 if (mddev
->degraded
== 0
1796 || bitmap
->events_cleared
== mddev
->events
)
1797 /* no need to keep dirty bits to optimise a
1798 * re-add of a missing device */
1799 start
= mddev
->recovery_cp
;
1801 mutex_lock(&mddev
->bitmap_info
.mutex
);
1802 err
= bitmap_init_from_disk(bitmap
, start
);
1803 mutex_unlock(&mddev
->bitmap_info
.mutex
);
1807 bitmap_mask_state(bitmap
, BITMAP_STALE
, MASK_UNSET
);
1809 /* Kick recovery in case any bits were set */
1810 set_bit(MD_RECOVERY_NEEDED
, &bitmap
->mddev
->recovery
);
1812 mddev
->thread
->timeout
= mddev
->bitmap_info
.daemon_sleep
;
1813 md_wakeup_thread(mddev
->thread
);
1815 bitmap_update_sb(bitmap
);
1817 if (bitmap
->flags
& BITMAP_WRITE_ERROR
)
1822 EXPORT_SYMBOL_GPL(bitmap_load
);
1824 void bitmap_status(struct seq_file
*seq
, struct bitmap
*bitmap
)
1826 unsigned long chunk_kb
;
1827 unsigned long flags
;
1832 spin_lock_irqsave(&bitmap
->lock
, flags
);
1833 chunk_kb
= bitmap
->mddev
->bitmap_info
.chunksize
>> 10;
1834 seq_printf(seq
, "bitmap: %lu/%lu pages [%luKB], "
1836 bitmap
->pages
- bitmap
->missing_pages
,
1838 (bitmap
->pages
- bitmap
->missing_pages
)
1839 << (PAGE_SHIFT
- 10),
1840 chunk_kb
? chunk_kb
: bitmap
->mddev
->bitmap_info
.chunksize
,
1841 chunk_kb
? "KB" : "B");
1842 if (bitmap
->storage
.file
) {
1843 seq_printf(seq
, ", file: ");
1844 seq_path(seq
, &bitmap
->storage
.file
->f_path
, " \t\n");
1847 seq_printf(seq
, "\n");
1848 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
1852 location_show(struct mddev
*mddev
, char *page
)
1855 if (mddev
->bitmap_info
.file
)
1856 len
= sprintf(page
, "file");
1857 else if (mddev
->bitmap_info
.offset
)
1858 len
= sprintf(page
, "%+lld", (long long)mddev
->bitmap_info
.offset
);
1860 len
= sprintf(page
, "none");
1861 len
+= sprintf(page
+len
, "\n");
1866 location_store(struct mddev
*mddev
, const char *buf
, size_t len
)
1870 if (!mddev
->pers
->quiesce
)
1872 if (mddev
->recovery
|| mddev
->sync_thread
)
1876 if (mddev
->bitmap
|| mddev
->bitmap_info
.file
||
1877 mddev
->bitmap_info
.offset
) {
1878 /* bitmap already configured. Only option is to clear it */
1879 if (strncmp(buf
, "none", 4) != 0)
1882 mddev
->pers
->quiesce(mddev
, 1);
1883 bitmap_destroy(mddev
);
1884 mddev
->pers
->quiesce(mddev
, 0);
1886 mddev
->bitmap_info
.offset
= 0;
1887 if (mddev
->bitmap_info
.file
) {
1888 struct file
*f
= mddev
->bitmap_info
.file
;
1889 mddev
->bitmap_info
.file
= NULL
;
1890 restore_bitmap_write_access(f
);
1894 /* No bitmap, OK to set a location */
1896 if (strncmp(buf
, "none", 4) == 0)
1897 /* nothing to be done */;
1898 else if (strncmp(buf
, "file:", 5) == 0) {
1899 /* Not supported yet */
1904 rv
= strict_strtoll(buf
+1, 10, &offset
);
1906 rv
= strict_strtoll(buf
, 10, &offset
);
1911 if (mddev
->bitmap_info
.external
== 0 &&
1912 mddev
->major_version
== 0 &&
1913 offset
!= mddev
->bitmap_info
.default_offset
)
1915 mddev
->bitmap_info
.offset
= offset
;
1917 mddev
->pers
->quiesce(mddev
, 1);
1918 rv
= bitmap_create(mddev
);
1920 rv
= bitmap_load(mddev
);
1922 bitmap_destroy(mddev
);
1923 mddev
->bitmap_info
.offset
= 0;
1925 mddev
->pers
->quiesce(mddev
, 0);
1931 if (!mddev
->external
) {
1932 /* Ensure new bitmap info is stored in
1933 * metadata promptly.
1935 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
1936 md_wakeup_thread(mddev
->thread
);
1941 static struct md_sysfs_entry bitmap_location
=
1942 __ATTR(location
, S_IRUGO
|S_IWUSR
, location_show
, location_store
);
1944 /* 'bitmap/space' is the space available at 'location' for the
1945 * bitmap. This allows the kernel to know when it is safe to
1946 * resize the bitmap to match a resized array.
1949 space_show(struct mddev
*mddev
, char *page
)
1951 return sprintf(page
, "%lu\n", mddev
->bitmap_info
.space
);
1955 space_store(struct mddev
*mddev
, const char *buf
, size_t len
)
1957 unsigned long sectors
;
1960 rv
= kstrtoul(buf
, 10, §ors
);
1967 if (mddev
->bitmap
&&
1968 sectors
< ((mddev
->bitmap
->storage
.file_pages
- 1)
1970 + mddev
->bitmap
->storage
.last_page_size
+ 511) >> 9)
1971 return -EFBIG
; /* Bitmap is too big for this small space */
1973 /* could make sure it isn't too big, but that isn't really
1974 * needed - user-space should be careful.
1976 mddev
->bitmap_info
.space
= sectors
;
1980 static struct md_sysfs_entry bitmap_space
=
1981 __ATTR(space
, S_IRUGO
|S_IWUSR
, space_show
, space_store
);
1984 timeout_show(struct mddev
*mddev
, char *page
)
1987 unsigned long secs
= mddev
->bitmap_info
.daemon_sleep
/ HZ
;
1988 unsigned long jifs
= mddev
->bitmap_info
.daemon_sleep
% HZ
;
1990 len
= sprintf(page
, "%lu", secs
);
1992 len
+= sprintf(page
+len
, ".%03u", jiffies_to_msecs(jifs
));
1993 len
+= sprintf(page
+len
, "\n");
1998 timeout_store(struct mddev
*mddev
, const char *buf
, size_t len
)
2000 /* timeout can be set at any time */
2001 unsigned long timeout
;
2002 int rv
= strict_strtoul_scaled(buf
, &timeout
, 4);
2006 /* just to make sure we don't overflow... */
2007 if (timeout
>= LONG_MAX
/ HZ
)
2010 timeout
= timeout
* HZ
/ 10000;
2012 if (timeout
>= MAX_SCHEDULE_TIMEOUT
)
2013 timeout
= MAX_SCHEDULE_TIMEOUT
-1;
2016 mddev
->bitmap_info
.daemon_sleep
= timeout
;
2017 if (mddev
->thread
) {
2018 /* if thread->timeout is MAX_SCHEDULE_TIMEOUT, then
2019 * the bitmap is all clean and we don't need to
2020 * adjust the timeout right now
2022 if (mddev
->thread
->timeout
< MAX_SCHEDULE_TIMEOUT
) {
2023 mddev
->thread
->timeout
= timeout
;
2024 md_wakeup_thread(mddev
->thread
);
2030 static struct md_sysfs_entry bitmap_timeout
=
2031 __ATTR(time_base
, S_IRUGO
|S_IWUSR
, timeout_show
, timeout_store
);
2034 backlog_show(struct mddev
*mddev
, char *page
)
2036 return sprintf(page
, "%lu\n", mddev
->bitmap_info
.max_write_behind
);
2040 backlog_store(struct mddev
*mddev
, const char *buf
, size_t len
)
2042 unsigned long backlog
;
2043 int rv
= strict_strtoul(buf
, 10, &backlog
);
2046 if (backlog
> COUNTER_MAX
)
2048 mddev
->bitmap_info
.max_write_behind
= backlog
;
2052 static struct md_sysfs_entry bitmap_backlog
=
2053 __ATTR(backlog
, S_IRUGO
|S_IWUSR
, backlog_show
, backlog_store
);
2056 chunksize_show(struct mddev
*mddev
, char *page
)
2058 return sprintf(page
, "%lu\n", mddev
->bitmap_info
.chunksize
);
2062 chunksize_store(struct mddev
*mddev
, const char *buf
, size_t len
)
2064 /* Can only be changed when no bitmap is active */
2066 unsigned long csize
;
2069 rv
= strict_strtoul(buf
, 10, &csize
);
2073 !is_power_of_2(csize
))
2075 mddev
->bitmap_info
.chunksize
= csize
;
2079 static struct md_sysfs_entry bitmap_chunksize
=
2080 __ATTR(chunksize
, S_IRUGO
|S_IWUSR
, chunksize_show
, chunksize_store
);
2082 static ssize_t
metadata_show(struct mddev
*mddev
, char *page
)
2084 return sprintf(page
, "%s\n", (mddev
->bitmap_info
.external
2085 ? "external" : "internal"));
2088 static ssize_t
metadata_store(struct mddev
*mddev
, const char *buf
, size_t len
)
2090 if (mddev
->bitmap
||
2091 mddev
->bitmap_info
.file
||
2092 mddev
->bitmap_info
.offset
)
2094 if (strncmp(buf
, "external", 8) == 0)
2095 mddev
->bitmap_info
.external
= 1;
2096 else if (strncmp(buf
, "internal", 8) == 0)
2097 mddev
->bitmap_info
.external
= 0;
2103 static struct md_sysfs_entry bitmap_metadata
=
2104 __ATTR(metadata
, S_IRUGO
|S_IWUSR
, metadata_show
, metadata_store
);
2106 static ssize_t
can_clear_show(struct mddev
*mddev
, char *page
)
2110 len
= sprintf(page
, "%s\n", (mddev
->bitmap
->need_sync
?
2113 len
= sprintf(page
, "\n");
2117 static ssize_t
can_clear_store(struct mddev
*mddev
, const char *buf
, size_t len
)
2119 if (mddev
->bitmap
== NULL
)
2121 if (strncmp(buf
, "false", 5) == 0)
2122 mddev
->bitmap
->need_sync
= 1;
2123 else if (strncmp(buf
, "true", 4) == 0) {
2124 if (mddev
->degraded
)
2126 mddev
->bitmap
->need_sync
= 0;
2132 static struct md_sysfs_entry bitmap_can_clear
=
2133 __ATTR(can_clear
, S_IRUGO
|S_IWUSR
, can_clear_show
, can_clear_store
);
2136 behind_writes_used_show(struct mddev
*mddev
, char *page
)
2138 if (mddev
->bitmap
== NULL
)
2139 return sprintf(page
, "0\n");
2140 return sprintf(page
, "%lu\n",
2141 mddev
->bitmap
->behind_writes_used
);
2145 behind_writes_used_reset(struct mddev
*mddev
, const char *buf
, size_t len
)
2148 mddev
->bitmap
->behind_writes_used
= 0;
2152 static struct md_sysfs_entry max_backlog_used
=
2153 __ATTR(max_backlog_used
, S_IRUGO
| S_IWUSR
,
2154 behind_writes_used_show
, behind_writes_used_reset
);
2156 static struct attribute
*md_bitmap_attrs
[] = {
2157 &bitmap_location
.attr
,
2159 &bitmap_timeout
.attr
,
2160 &bitmap_backlog
.attr
,
2161 &bitmap_chunksize
.attr
,
2162 &bitmap_metadata
.attr
,
2163 &bitmap_can_clear
.attr
,
2164 &max_backlog_used
.attr
,
2167 struct attribute_group md_bitmap_group
= {
2169 .attrs
= md_bitmap_attrs
,