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
;
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
== bitmap
->file_pages
-1)
206 size
= roundup(bitmap
->last_page_size
,
207 bdev_logical_block_size(bdev
));
208 /* Just make sure we aren't corrupting data or
211 if (mddev
->external
) {
212 /* Bitmap could be anywhere. */
213 if (rdev
->sb_start
+ offset
+ (page
->index
217 rdev
->sb_start
+ offset
218 < (rdev
->data_offset
+ mddev
->dev_sectors
221 } else if (offset
< 0) {
222 /* DATA BITMAP METADATA */
224 + (long)(page
->index
* (PAGE_SIZE
/512))
226 /* bitmap runs in to metadata */
228 if (rdev
->data_offset
+ mddev
->dev_sectors
229 > rdev
->sb_start
+ offset
)
230 /* data runs in to bitmap */
232 } else if (rdev
->sb_start
< rdev
->data_offset
) {
233 /* METADATA BITMAP DATA */
236 + page
->index
*(PAGE_SIZE
/512) + size
/512
238 /* bitmap runs in to data */
241 /* DATA METADATA BITMAP - no problems */
243 md_super_write(mddev
, rdev
,
244 rdev
->sb_start
+ offset
245 + page
->index
* (PAGE_SIZE
/512),
251 md_super_wait(mddev
);
258 static void bitmap_file_kick(struct bitmap
*bitmap
);
260 * write out a page to a file
262 static void write_page(struct bitmap
*bitmap
, struct page
*page
, int wait
)
264 struct buffer_head
*bh
;
266 if (bitmap
->file
== NULL
) {
267 switch (write_sb_page(bitmap
, page
, wait
)) {
269 bitmap
->flags
|= BITMAP_WRITE_ERROR
;
273 bh
= page_buffers(page
);
275 while (bh
&& bh
->b_blocknr
) {
276 atomic_inc(&bitmap
->pending_writes
);
277 set_buffer_locked(bh
);
278 set_buffer_mapped(bh
);
279 submit_bh(WRITE
| REQ_SYNC
, bh
);
280 bh
= bh
->b_this_page
;
284 wait_event(bitmap
->write_wait
,
285 atomic_read(&bitmap
->pending_writes
)==0);
287 if (bitmap
->flags
& BITMAP_WRITE_ERROR
)
288 bitmap_file_kick(bitmap
);
291 static void end_bitmap_write(struct buffer_head
*bh
, int uptodate
)
293 struct bitmap
*bitmap
= bh
->b_private
;
297 spin_lock_irqsave(&bitmap
->lock
, flags
);
298 bitmap
->flags
|= BITMAP_WRITE_ERROR
;
299 spin_unlock_irqrestore(&bitmap
->lock
, 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 (bitmap
->flags
& BITMAP_WRITE_ERROR
)
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
->sb_page
) /* no superblock */
413 sb
= kmap_atomic(bitmap
->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
->sb_page
, 1);
427 /* print out the bitmap file superblock */
428 void bitmap_print_sb(struct bitmap
*bitmap
)
432 if (!bitmap
|| !bitmap
->sb_page
)
434 sb
= kmap_atomic(bitmap
->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
->sb_page
= alloc_page(GFP_KERNEL
);
474 if (IS_ERR(bitmap
->sb_page
)) {
475 err
= PTR_ERR(bitmap
->sb_page
);
476 bitmap
->sb_page
= NULL
;
479 bitmap
->sb_page
->index
= 0;
481 sb
= kmap_atomic(bitmap
->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 bitmap
->flags
|= BITMAP_STALE
;
520 sb
->state
|= cpu_to_le32(BITMAP_STALE
);
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
->file
&& !bitmap
->mddev
->bitmap_info
.offset
) {
540 chunksize
= 128 * 1024 * 1024;
541 daemon_sleep
= 5 * HZ
;
543 bitmap
->flags
= BITMAP_STALE
;
547 /* page 0 is the superblock, read it... */
548 sb_page
= alloc_page(GFP_KERNEL
);
551 bitmap
->sb_page
= sb_page
;
554 loff_t isize
= i_size_read(bitmap
->file
->f_mapping
->host
);
555 int bytes
= isize
> PAGE_SIZE
? PAGE_SIZE
: isize
;
557 err
= read_page(bitmap
->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 sb
->state
|= cpu_to_le32(BITMAP_STALE
);
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 bitmap
->flags
|= BITMAP_HOSTENDIAN
;
623 bitmap
->events_cleared
= le64_to_cpu(sb
->events_cleared
);
628 if (bitmap
->flags
& BITMAP_STALE
)
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
);
638 enum bitmap_mask_op
{
643 /* record the state of the bitmap in the superblock. Return the old value */
644 static int bitmap_mask_state(struct bitmap
*bitmap
, enum bitmap_state bits
,
645 enum bitmap_mask_op op
)
650 if (!bitmap
->sb_page
) /* can't set the state */
652 sb
= kmap_atomic(bitmap
->sb_page
);
653 old
= le32_to_cpu(sb
->state
) & bits
;
656 sb
->state
|= cpu_to_le32(bits
);
657 bitmap
->flags
|= bits
;
660 sb
->state
&= cpu_to_le32(~bits
);
661 bitmap
->flags
&= ~bits
;
671 * general bitmap file operations
677 * Use one bit per "chunk" (block set). We do the disk I/O on the bitmap
678 * file a page at a time. There's a superblock at the start of the file.
680 /* calculate the index of the page that contains this bit */
681 static inline unsigned long file_page_index(struct bitmap
*bitmap
, unsigned long chunk
)
683 if (!bitmap
->mddev
->bitmap_info
.external
)
684 chunk
+= sizeof(bitmap_super_t
) << 3;
685 return chunk
>> PAGE_BIT_SHIFT
;
688 /* calculate the (bit) offset of this bit within a page */
689 static inline unsigned long file_page_offset(struct bitmap
*bitmap
, unsigned long chunk
)
691 if (!bitmap
->mddev
->bitmap_info
.external
)
692 chunk
+= sizeof(bitmap_super_t
) << 3;
693 return chunk
& (PAGE_BITS
- 1);
697 * return a pointer to the page in the filemap that contains the given bit
699 * this lookup is complicated by the fact that the bitmap sb might be exactly
700 * 1 page (e.g., x86) or less than 1 page -- so the bitmap might start on page
703 static inline struct page
*filemap_get_page(struct bitmap
*bitmap
,
706 if (file_page_index(bitmap
, chunk
) >= bitmap
->file_pages
)
708 return bitmap
->filemap
[file_page_index(bitmap
, chunk
)
709 - file_page_index(bitmap
, 0)];
712 static void bitmap_file_unmap(struct bitmap
*bitmap
)
714 struct page
**map
, *sb_page
;
719 spin_lock_irqsave(&bitmap
->lock
, flags
);
720 map
= bitmap
->filemap
;
721 bitmap
->filemap
= NULL
;
722 attr
= bitmap
->filemap_attr
;
723 bitmap
->filemap_attr
= NULL
;
724 pages
= bitmap
->file_pages
;
725 bitmap
->file_pages
= 0;
726 sb_page
= bitmap
->sb_page
;
727 bitmap
->sb_page
= NULL
;
728 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
731 if (map
[pages
] != sb_page
) /* 0 is sb_page, release it below */
732 free_buffers(map
[pages
]);
737 free_buffers(sb_page
);
740 static void bitmap_file_put(struct bitmap
*bitmap
)
745 spin_lock_irqsave(&bitmap
->lock
, flags
);
748 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
751 wait_event(bitmap
->write_wait
,
752 atomic_read(&bitmap
->pending_writes
)==0);
753 bitmap_file_unmap(bitmap
);
756 struct inode
*inode
= file
->f_path
.dentry
->d_inode
;
757 invalidate_mapping_pages(inode
->i_mapping
, 0, -1);
763 * bitmap_file_kick - if an error occurs while manipulating the bitmap file
764 * then it is no longer reliable, so we stop using it and we mark the file
765 * as failed in the superblock
767 static void bitmap_file_kick(struct bitmap
*bitmap
)
769 char *path
, *ptr
= NULL
;
771 if (bitmap_mask_state(bitmap
, BITMAP_STALE
, MASK_SET
) == 0) {
772 bitmap_update_sb(bitmap
);
775 path
= kmalloc(PAGE_SIZE
, GFP_KERNEL
);
777 ptr
= d_path(&bitmap
->file
->f_path
, path
,
781 "%s: kicking failed bitmap file %s from array!\n",
782 bmname(bitmap
), IS_ERR(ptr
) ? "" : ptr
);
787 "%s: disabling internal bitmap due to errors\n",
791 bitmap_file_put(bitmap
);
796 enum bitmap_page_attr
{
797 BITMAP_PAGE_DIRTY
= 0, /* there are set bits that need to be synced */
798 BITMAP_PAGE_PENDING
= 1, /* there are bits that are being cleaned.
799 * i.e. counter is 1 or 2. */
800 BITMAP_PAGE_NEEDWRITE
= 2, /* there are cleared bits that need to be synced */
803 static inline void set_page_attr(struct bitmap
*bitmap
, int pnum
,
804 enum bitmap_page_attr attr
)
806 __set_bit((pnum
<<2) + attr
, bitmap
->filemap_attr
);
809 static inline void clear_page_attr(struct bitmap
*bitmap
, int pnum
,
810 enum bitmap_page_attr attr
)
812 __clear_bit((pnum
<<2) + attr
, bitmap
->filemap_attr
);
815 static inline unsigned long test_page_attr(struct bitmap
*bitmap
, int pnum
,
816 enum bitmap_page_attr attr
)
818 return test_bit((pnum
<<2) + attr
, bitmap
->filemap_attr
);
822 * bitmap_file_set_bit -- called before performing a write to the md device
823 * to set (and eventually sync) a particular bit in the bitmap file
825 * we set the bit immediately, then we record the page number so that
826 * when an unplug occurs, we can flush the dirty pages out to disk
828 static void bitmap_file_set_bit(struct bitmap
*bitmap
, sector_t block
)
833 unsigned long chunk
= block
>> bitmap
->chunkshift
;
835 page
= filemap_get_page(bitmap
, chunk
);
838 bit
= file_page_offset(bitmap
, chunk
);
841 kaddr
= kmap_atomic(page
);
842 if (bitmap
->flags
& BITMAP_HOSTENDIAN
)
845 __set_bit_le(bit
, kaddr
);
846 kunmap_atomic(kaddr
);
847 pr_debug("set file bit %lu page %lu\n", bit
, page
->index
);
848 /* record page number so it gets flushed to disk when unplug occurs */
849 set_page_attr(bitmap
, page
->index
, BITMAP_PAGE_DIRTY
);
852 static void bitmap_file_clear_bit(struct bitmap
*bitmap
, sector_t block
)
857 unsigned long chunk
= block
>> bitmap
->chunkshift
;
859 page
= filemap_get_page(bitmap
, chunk
);
862 bit
= file_page_offset(bitmap
, chunk
);
863 paddr
= kmap_atomic(page
);
864 if (bitmap
->flags
& BITMAP_HOSTENDIAN
)
865 clear_bit(bit
, paddr
);
867 __clear_bit_le(bit
, paddr
);
868 kunmap_atomic(paddr
);
869 if (!test_page_attr(bitmap
, page
->index
, BITMAP_PAGE_NEEDWRITE
)) {
870 set_page_attr(bitmap
, page
->index
, BITMAP_PAGE_PENDING
);
871 bitmap
->allclean
= 0;
875 /* this gets called when the md device is ready to unplug its underlying
876 * (slave) device queues -- before we let any writes go down, we need to
877 * sync the dirty pages of the bitmap file to disk */
878 void bitmap_unplug(struct bitmap
*bitmap
)
880 unsigned long i
, flags
;
881 int dirty
, need_write
;
884 if (!bitmap
|| !bitmap
->filemap
)
887 /* look at each page to see if there are any set bits that need to be
888 * flushed out to disk */
889 for (i
= 0; i
< bitmap
->file_pages
; i
++) {
890 spin_lock_irqsave(&bitmap
->lock
, flags
);
891 if (!bitmap
->filemap
) {
892 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
895 dirty
= test_page_attr(bitmap
, i
, BITMAP_PAGE_DIRTY
);
896 need_write
= test_page_attr(bitmap
, i
, BITMAP_PAGE_NEEDWRITE
);
897 clear_page_attr(bitmap
, i
, BITMAP_PAGE_DIRTY
);
898 clear_page_attr(bitmap
, i
, BITMAP_PAGE_NEEDWRITE
);
899 if (dirty
|| need_write
)
900 clear_page_attr(bitmap
, i
, BITMAP_PAGE_PENDING
);
903 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
905 if (dirty
|| need_write
)
906 write_page(bitmap
, bitmap
->filemap
[i
], 0);
908 if (wait
) { /* if any writes were performed, we need to wait on them */
910 wait_event(bitmap
->write_wait
,
911 atomic_read(&bitmap
->pending_writes
)==0);
913 md_super_wait(bitmap
->mddev
);
915 if (bitmap
->flags
& BITMAP_WRITE_ERROR
)
916 bitmap_file_kick(bitmap
);
918 EXPORT_SYMBOL(bitmap_unplug
);
920 static void bitmap_set_memory_bits(struct bitmap
*bitmap
, sector_t offset
, int needed
);
921 /* * bitmap_init_from_disk -- called at bitmap_create time to initialize
922 * the in-memory bitmap from the on-disk bitmap -- also, sets up the
923 * memory mapping of the bitmap file
925 * if there's no bitmap file, or if the bitmap file had been
926 * previously kicked from the array, we mark all the bits as
927 * 1's in order to cause a full resync.
929 * We ignore all bits for sectors that end earlier than 'start'.
930 * This is used when reading an out-of-date bitmap...
932 static int bitmap_init_from_disk(struct bitmap
*bitmap
, sector_t start
)
934 unsigned long i
, chunks
, index
, oldindex
, bit
;
936 struct page
*page
= NULL
;
937 unsigned long num_pages
, bit_cnt
= 0;
939 unsigned long bytes
, offset
;
944 chunks
= bitmap
->chunks
;
947 if (!file
&& !bitmap
->mddev
->bitmap_info
.offset
) {
948 /* No permanent bitmap - fill with '1s'. */
949 bitmap
->filemap
= NULL
;
950 bitmap
->file_pages
= 0;
951 for (i
= 0; i
< chunks
; i
++) {
952 /* if the disk bit is set, set the memory bit */
953 int needed
= ((sector_t
)(i
+1) << (bitmap
->chunkshift
)
955 bitmap_set_memory_bits(bitmap
,
956 (sector_t
)i
<< bitmap
->chunkshift
,
962 outofdate
= bitmap
->flags
& BITMAP_STALE
;
964 printk(KERN_INFO
"%s: bitmap file is out of date, doing full "
965 "recovery\n", bmname(bitmap
));
967 bytes
= DIV_ROUND_UP(bitmap
->chunks
, 8);
968 if (!bitmap
->mddev
->bitmap_info
.external
)
969 bytes
+= sizeof(bitmap_super_t
);
971 num_pages
= DIV_ROUND_UP(bytes
, PAGE_SIZE
);
973 if (file
&& i_size_read(file
->f_mapping
->host
) < bytes
) {
974 printk(KERN_INFO
"%s: bitmap file too short %lu < %lu\n",
976 (unsigned long) i_size_read(file
->f_mapping
->host
),
983 bitmap
->filemap
= kmalloc(sizeof(struct page
*) * num_pages
, GFP_KERNEL
);
984 if (!bitmap
->filemap
)
989 if (bitmap
->sb_page
) {
990 bitmap
->filemap
[0] = bitmap
->sb_page
;
992 offset
= sizeof(bitmap_super_t
);
994 for ( ; pnum
< num_pages
; pnum
++) {
995 bitmap
->filemap
[pnum
] = alloc_page(GFP_KERNEL
);
996 if (!bitmap
->filemap
[pnum
]) {
997 bitmap
->file_pages
= pnum
;
1001 bitmap
->file_pages
= pnum
;
1003 /* We need 4 bits per page, rounded up to a multiple of sizeof(unsigned long) */
1004 bitmap
->filemap_attr
= kzalloc(
1005 roundup(DIV_ROUND_UP(num_pages
*4, 8), sizeof(unsigned long)),
1007 if (!bitmap
->filemap_attr
)
1012 for (i
= 0; i
< chunks
; i
++) {
1014 index
= file_page_index(bitmap
, i
);
1015 bit
= file_page_offset(bitmap
, i
);
1016 if (index
!= oldindex
) { /* this is a new page, read it in */
1018 /* unmap the old page, we're done with it */
1019 if (index
== num_pages
-1)
1020 count
= bytes
- index
* PAGE_SIZE
;
1023 page
= bitmap
->filemap
[index
];
1025 ret
= read_page(file
, index
, bitmap
,
1030 bitmap
->mddev
->bitmap_info
.offset
,
1039 bitmap
->last_page_size
= count
;
1043 * if bitmap is out of date, dirty the
1044 * whole page and write it out
1046 paddr
= kmap_atomic(page
);
1047 memset(paddr
+ offset
, 0xff,
1048 PAGE_SIZE
- offset
);
1049 kunmap_atomic(paddr
);
1050 write_page(bitmap
, page
, 1);
1053 if (bitmap
->flags
& BITMAP_WRITE_ERROR
)
1057 paddr
= kmap_atomic(page
);
1058 if (bitmap
->flags
& BITMAP_HOSTENDIAN
)
1059 b
= test_bit(bit
, paddr
);
1061 b
= test_bit_le(bit
, paddr
);
1062 kunmap_atomic(paddr
);
1064 /* if the disk bit is set, set the memory bit */
1065 int needed
= ((sector_t
)(i
+1) << bitmap
->chunkshift
1067 bitmap_set_memory_bits(bitmap
,
1068 (sector_t
)i
<< bitmap
->chunkshift
,
1075 printk(KERN_INFO
"%s: bitmap initialized from disk: "
1076 "read %lu/%lu pages, set %lu of %lu bits\n",
1077 bmname(bitmap
), bitmap
->file_pages
, num_pages
, bit_cnt
, chunks
);
1082 printk(KERN_INFO
"%s: bitmap initialisation failed: %d\n",
1083 bmname(bitmap
), ret
);
1087 void bitmap_write_all(struct bitmap
*bitmap
)
1089 /* We don't actually write all bitmap blocks here,
1090 * just flag them as needing to be written
1094 if (!bitmap
|| !bitmap
->filemap
)
1097 /* Only one copy, so nothing needed */
1100 spin_lock_irq(&bitmap
->lock
);
1101 for (i
= 0; i
< bitmap
->file_pages
; i
++)
1102 set_page_attr(bitmap
, i
,
1103 BITMAP_PAGE_NEEDWRITE
);
1104 bitmap
->allclean
= 0;
1105 spin_unlock_irq(&bitmap
->lock
);
1108 static void bitmap_count_page(struct bitmap
*bitmap
, sector_t offset
, int inc
)
1110 sector_t chunk
= offset
>> bitmap
->chunkshift
;
1111 unsigned long page
= chunk
>> PAGE_COUNTER_SHIFT
;
1112 bitmap
->bp
[page
].count
+= inc
;
1113 bitmap_checkfree(bitmap
, page
);
1116 static void bitmap_set_pending(struct bitmap
*bitmap
, sector_t offset
)
1118 sector_t chunk
= offset
>> bitmap
->chunkshift
;
1119 unsigned long page
= chunk
>> PAGE_COUNTER_SHIFT
;
1120 struct bitmap_page
*bp
= &bitmap
->bp
[page
];
1126 static bitmap_counter_t
*bitmap_get_counter(struct bitmap
*bitmap
,
1127 sector_t offset
, sector_t
*blocks
,
1131 * bitmap daemon -- periodically wakes up to clean bits and flush pages
1135 void bitmap_daemon_work(struct mddev
*mddev
)
1137 struct bitmap
*bitmap
;
1139 unsigned long nextpage
;
1140 unsigned long flags
;
1143 /* Use a mutex to guard daemon_work against
1146 mutex_lock(&mddev
->bitmap_info
.mutex
);
1147 bitmap
= mddev
->bitmap
;
1148 if (bitmap
== NULL
) {
1149 mutex_unlock(&mddev
->bitmap_info
.mutex
);
1152 if (time_before(jiffies
, bitmap
->daemon_lastrun
1153 + mddev
->bitmap_info
.daemon_sleep
))
1156 bitmap
->daemon_lastrun
= jiffies
;
1157 if (bitmap
->allclean
) {
1158 mddev
->thread
->timeout
= MAX_SCHEDULE_TIMEOUT
;
1161 bitmap
->allclean
= 1;
1163 /* Any file-page which is PENDING now needs to be written.
1164 * So set NEEDWRITE now, then after we make any last-minute changes
1167 spin_lock_irqsave(&bitmap
->lock
, flags
);
1168 for (j
= 0; j
< bitmap
->file_pages
; j
++)
1169 if (test_page_attr(bitmap
, j
,
1170 BITMAP_PAGE_PENDING
)) {
1171 set_page_attr(bitmap
, j
,
1172 BITMAP_PAGE_NEEDWRITE
);
1173 clear_page_attr(bitmap
, j
,
1174 BITMAP_PAGE_PENDING
);
1177 if (bitmap
->need_sync
&&
1178 mddev
->bitmap_info
.external
== 0) {
1179 /* Arrange for superblock update as well as
1182 bitmap
->need_sync
= 0;
1183 if (bitmap
->filemap
) {
1184 sb
= kmap_atomic(bitmap
->sb_page
);
1185 sb
->events_cleared
=
1186 cpu_to_le64(bitmap
->events_cleared
);
1188 set_page_attr(bitmap
, 0,
1189 BITMAP_PAGE_NEEDWRITE
);
1192 /* Now look at the bitmap counters and if any are '2' or '1',
1193 * decrement and handle accordingly.
1196 for (j
= 0; j
< bitmap
->chunks
; j
++) {
1197 bitmap_counter_t
*bmc
;
1198 sector_t block
= (sector_t
)j
<< bitmap
->chunkshift
;
1200 if (j
== nextpage
) {
1201 nextpage
+= PAGE_COUNTER_RATIO
;
1202 if (!bitmap
->bp
[j
>> PAGE_COUNTER_SHIFT
].pending
) {
1203 j
|= PAGE_COUNTER_MASK
;
1206 bitmap
->bp
[j
>> PAGE_COUNTER_SHIFT
].pending
= 0;
1208 bmc
= bitmap_get_counter(bitmap
,
1213 j
|= PAGE_COUNTER_MASK
;
1216 if (*bmc
== 1 && !bitmap
->need_sync
) {
1217 /* We can clear the bit */
1219 bitmap_count_page(bitmap
, block
, -1);
1220 bitmap_file_clear_bit(bitmap
, block
);
1221 } else if (*bmc
&& *bmc
<= 2) {
1223 bitmap_set_pending(bitmap
, block
);
1224 bitmap
->allclean
= 0;
1228 /* Now start writeout on any page in NEEDWRITE that isn't DIRTY.
1229 * DIRTY pages need to be written by bitmap_unplug so it can wait
1231 * If we find any DIRTY page we stop there and let bitmap_unplug
1232 * handle all the rest. This is important in the case where
1233 * the first blocking holds the superblock and it has been updated.
1234 * We mustn't write any other blocks before the superblock.
1236 for (j
= 0; j
< bitmap
->file_pages
; j
++) {
1238 if (test_page_attr(bitmap
, j
,
1240 /* bitmap_unplug will handle the rest */
1242 if (test_page_attr(bitmap
, j
,
1243 BITMAP_PAGE_NEEDWRITE
)) {
1244 clear_page_attr(bitmap
, j
,
1245 BITMAP_PAGE_NEEDWRITE
);
1246 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
1247 write_page(bitmap
, bitmap
->filemap
[j
], 0);
1248 spin_lock_irqsave(&bitmap
->lock
, flags
);
1249 if (!bitmap
->filemap
)
1253 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
1256 if (bitmap
->allclean
== 0)
1257 mddev
->thread
->timeout
=
1258 mddev
->bitmap_info
.daemon_sleep
;
1259 mutex_unlock(&mddev
->bitmap_info
.mutex
);
1262 static bitmap_counter_t
*bitmap_get_counter(struct bitmap
*bitmap
,
1263 sector_t offset
, sector_t
*blocks
,
1265 __releases(bitmap
->lock
)
1266 __acquires(bitmap
->lock
)
1268 /* If 'create', we might release the lock and reclaim it.
1269 * The lock must have been taken with interrupts enabled.
1270 * If !create, we don't release the lock.
1272 sector_t chunk
= offset
>> bitmap
->chunkshift
;
1273 unsigned long page
= chunk
>> PAGE_COUNTER_SHIFT
;
1274 unsigned long pageoff
= (chunk
& PAGE_COUNTER_MASK
) << COUNTER_BYTE_SHIFT
;
1278 err
= bitmap_checkpage(bitmap
, page
, create
);
1280 if (bitmap
->bp
[page
].hijacked
||
1281 bitmap
->bp
[page
].map
== NULL
)
1282 csize
= ((sector_t
)1) << (bitmap
->chunkshift
+
1283 PAGE_COUNTER_SHIFT
- 1);
1285 csize
= ((sector_t
)1) << bitmap
->chunkshift
;
1286 *blocks
= csize
- (offset
& (csize
- 1));
1291 /* now locked ... */
1293 if (bitmap
->bp
[page
].hijacked
) { /* hijacked pointer */
1294 /* should we use the first or second counter field
1295 * of the hijacked pointer? */
1296 int hi
= (pageoff
> PAGE_COUNTER_MASK
);
1297 return &((bitmap_counter_t
*)
1298 &bitmap
->bp
[page
].map
)[hi
];
1299 } else /* page is allocated */
1300 return (bitmap_counter_t
*)
1301 &(bitmap
->bp
[page
].map
[pageoff
]);
1304 int bitmap_startwrite(struct bitmap
*bitmap
, sector_t offset
, unsigned long sectors
, int behind
)
1311 atomic_inc(&bitmap
->behind_writes
);
1312 bw
= atomic_read(&bitmap
->behind_writes
);
1313 if (bw
> bitmap
->behind_writes_used
)
1314 bitmap
->behind_writes_used
= bw
;
1316 pr_debug("inc write-behind count %d/%lu\n",
1317 bw
, bitmap
->mddev
->bitmap_info
.max_write_behind
);
1322 bitmap_counter_t
*bmc
;
1324 spin_lock_irq(&bitmap
->lock
);
1325 bmc
= bitmap_get_counter(bitmap
, offset
, &blocks
, 1);
1327 spin_unlock_irq(&bitmap
->lock
);
1331 if (unlikely(COUNTER(*bmc
) == COUNTER_MAX
)) {
1332 DEFINE_WAIT(__wait
);
1333 /* note that it is safe to do the prepare_to_wait
1334 * after the test as long as we do it before dropping
1337 prepare_to_wait(&bitmap
->overflow_wait
, &__wait
,
1338 TASK_UNINTERRUPTIBLE
);
1339 spin_unlock_irq(&bitmap
->lock
);
1341 finish_wait(&bitmap
->overflow_wait
, &__wait
);
1347 bitmap_file_set_bit(bitmap
, offset
);
1348 bitmap_count_page(bitmap
, offset
, 1);
1356 spin_unlock_irq(&bitmap
->lock
);
1359 if (sectors
> blocks
)
1366 EXPORT_SYMBOL(bitmap_startwrite
);
1368 void bitmap_endwrite(struct bitmap
*bitmap
, sector_t offset
, unsigned long sectors
,
1369 int success
, int behind
)
1374 if (atomic_dec_and_test(&bitmap
->behind_writes
))
1375 wake_up(&bitmap
->behind_wait
);
1376 pr_debug("dec write-behind count %d/%lu\n",
1377 atomic_read(&bitmap
->behind_writes
),
1378 bitmap
->mddev
->bitmap_info
.max_write_behind
);
1383 unsigned long flags
;
1384 bitmap_counter_t
*bmc
;
1386 spin_lock_irqsave(&bitmap
->lock
, flags
);
1387 bmc
= bitmap_get_counter(bitmap
, offset
, &blocks
, 0);
1389 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
1393 if (success
&& !bitmap
->mddev
->degraded
&&
1394 bitmap
->events_cleared
< bitmap
->mddev
->events
) {
1395 bitmap
->events_cleared
= bitmap
->mddev
->events
;
1396 bitmap
->need_sync
= 1;
1397 sysfs_notify_dirent_safe(bitmap
->sysfs_can_clear
);
1400 if (!success
&& !NEEDED(*bmc
))
1401 *bmc
|= NEEDED_MASK
;
1403 if (COUNTER(*bmc
) == COUNTER_MAX
)
1404 wake_up(&bitmap
->overflow_wait
);
1408 bitmap_set_pending(bitmap
, offset
);
1409 bitmap
->allclean
= 0;
1411 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
1413 if (sectors
> blocks
)
1419 EXPORT_SYMBOL(bitmap_endwrite
);
1421 static int __bitmap_start_sync(struct bitmap
*bitmap
, sector_t offset
, sector_t
*blocks
,
1424 bitmap_counter_t
*bmc
;
1426 if (bitmap
== NULL
) {/* FIXME or bitmap set as 'failed' */
1428 return 1; /* always resync if no bitmap */
1430 spin_lock_irq(&bitmap
->lock
);
1431 bmc
= bitmap_get_counter(bitmap
, offset
, blocks
, 0);
1437 else if (NEEDED(*bmc
)) {
1439 if (!degraded
) { /* don't set/clear bits if degraded */
1440 *bmc
|= RESYNC_MASK
;
1441 *bmc
&= ~NEEDED_MASK
;
1445 spin_unlock_irq(&bitmap
->lock
);
1449 int bitmap_start_sync(struct bitmap
*bitmap
, sector_t offset
, sector_t
*blocks
,
1452 /* bitmap_start_sync must always report on multiples of whole
1453 * pages, otherwise resync (which is very PAGE_SIZE based) will
1455 * So call __bitmap_start_sync repeatedly (if needed) until
1456 * At least PAGE_SIZE>>9 blocks are covered.
1457 * Return the 'or' of the result.
1463 while (*blocks
< (PAGE_SIZE
>>9)) {
1464 rv
|= __bitmap_start_sync(bitmap
, offset
,
1465 &blocks1
, degraded
);
1471 EXPORT_SYMBOL(bitmap_start_sync
);
1473 void bitmap_end_sync(struct bitmap
*bitmap
, sector_t offset
, sector_t
*blocks
, int aborted
)
1475 bitmap_counter_t
*bmc
;
1476 unsigned long flags
;
1478 if (bitmap
== NULL
) {
1482 spin_lock_irqsave(&bitmap
->lock
, flags
);
1483 bmc
= bitmap_get_counter(bitmap
, offset
, blocks
, 0);
1488 *bmc
&= ~RESYNC_MASK
;
1490 if (!NEEDED(*bmc
) && aborted
)
1491 *bmc
|= NEEDED_MASK
;
1494 bitmap_set_pending(bitmap
, offset
);
1495 bitmap
->allclean
= 0;
1500 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
1502 EXPORT_SYMBOL(bitmap_end_sync
);
1504 void bitmap_close_sync(struct bitmap
*bitmap
)
1506 /* Sync has finished, and any bitmap chunks that weren't synced
1507 * properly have been aborted. It remains to us to clear the
1508 * RESYNC bit wherever it is still on
1510 sector_t sector
= 0;
1514 while (sector
< bitmap
->mddev
->resync_max_sectors
) {
1515 bitmap_end_sync(bitmap
, sector
, &blocks
, 0);
1519 EXPORT_SYMBOL(bitmap_close_sync
);
1521 void bitmap_cond_end_sync(struct bitmap
*bitmap
, sector_t sector
)
1529 bitmap
->last_end_sync
= jiffies
;
1532 if (time_before(jiffies
, (bitmap
->last_end_sync
1533 + bitmap
->mddev
->bitmap_info
.daemon_sleep
)))
1535 wait_event(bitmap
->mddev
->recovery_wait
,
1536 atomic_read(&bitmap
->mddev
->recovery_active
) == 0);
1538 bitmap
->mddev
->curr_resync_completed
= sector
;
1539 set_bit(MD_CHANGE_CLEAN
, &bitmap
->mddev
->flags
);
1540 sector
&= ~((1ULL << bitmap
->chunkshift
) - 1);
1542 while (s
< sector
&& s
< bitmap
->mddev
->resync_max_sectors
) {
1543 bitmap_end_sync(bitmap
, s
, &blocks
, 0);
1546 bitmap
->last_end_sync
= jiffies
;
1547 sysfs_notify(&bitmap
->mddev
->kobj
, NULL
, "sync_completed");
1549 EXPORT_SYMBOL(bitmap_cond_end_sync
);
1551 static void bitmap_set_memory_bits(struct bitmap
*bitmap
, sector_t offset
, int needed
)
1553 /* For each chunk covered by any of these sectors, set the
1554 * counter to 2 and possibly set resync_needed. They should all
1555 * be 0 at this point
1559 bitmap_counter_t
*bmc
;
1560 spin_lock_irq(&bitmap
->lock
);
1561 bmc
= bitmap_get_counter(bitmap
, offset
, &secs
, 1);
1563 spin_unlock_irq(&bitmap
->lock
);
1567 *bmc
= 2 | (needed
? NEEDED_MASK
: 0);
1568 bitmap_count_page(bitmap
, offset
, 1);
1569 bitmap_set_pending(bitmap
, offset
);
1570 bitmap
->allclean
= 0;
1572 spin_unlock_irq(&bitmap
->lock
);
1575 /* dirty the memory and file bits for bitmap chunks "s" to "e" */
1576 void bitmap_dirty_bits(struct bitmap
*bitmap
, unsigned long s
, unsigned long e
)
1578 unsigned long chunk
;
1580 for (chunk
= s
; chunk
<= e
; chunk
++) {
1581 sector_t sec
= (sector_t
)chunk
<< bitmap
->chunkshift
;
1582 bitmap_set_memory_bits(bitmap
, sec
, 1);
1583 spin_lock_irq(&bitmap
->lock
);
1584 bitmap_file_set_bit(bitmap
, sec
);
1585 spin_unlock_irq(&bitmap
->lock
);
1586 if (sec
< bitmap
->mddev
->recovery_cp
)
1587 /* We are asserting that the array is dirty,
1588 * so move the recovery_cp address back so
1589 * that it is obvious that it is dirty
1591 bitmap
->mddev
->recovery_cp
= sec
;
1596 * flush out any pending updates
1598 void bitmap_flush(struct mddev
*mddev
)
1600 struct bitmap
*bitmap
= mddev
->bitmap
;
1603 if (!bitmap
) /* there was no bitmap */
1606 /* run the daemon_work three time to ensure everything is flushed
1609 sleep
= mddev
->bitmap_info
.daemon_sleep
* 2;
1610 bitmap
->daemon_lastrun
-= sleep
;
1611 bitmap_daemon_work(mddev
);
1612 bitmap
->daemon_lastrun
-= sleep
;
1613 bitmap_daemon_work(mddev
);
1614 bitmap
->daemon_lastrun
-= sleep
;
1615 bitmap_daemon_work(mddev
);
1616 bitmap_update_sb(bitmap
);
1620 * free memory that was allocated
1622 static void bitmap_free(struct bitmap
*bitmap
)
1624 unsigned long k
, pages
;
1625 struct bitmap_page
*bp
;
1627 if (!bitmap
) /* there was no bitmap */
1630 /* release the bitmap file and kill the daemon */
1631 bitmap_file_put(bitmap
);
1634 pages
= bitmap
->pages
;
1636 /* free all allocated memory */
1638 if (bp
) /* deallocate the page memory */
1639 for (k
= 0; k
< pages
; k
++)
1640 if (bp
[k
].map
&& !bp
[k
].hijacked
)
1646 void bitmap_destroy(struct mddev
*mddev
)
1648 struct bitmap
*bitmap
= mddev
->bitmap
;
1650 if (!bitmap
) /* there was no bitmap */
1653 mutex_lock(&mddev
->bitmap_info
.mutex
);
1654 mddev
->bitmap
= NULL
; /* disconnect from the md device */
1655 mutex_unlock(&mddev
->bitmap_info
.mutex
);
1657 mddev
->thread
->timeout
= MAX_SCHEDULE_TIMEOUT
;
1659 if (bitmap
->sysfs_can_clear
)
1660 sysfs_put(bitmap
->sysfs_can_clear
);
1662 bitmap_free(bitmap
);
1666 * initialize the bitmap structure
1667 * if this returns an error, bitmap_destroy must be called to do clean up
1669 int bitmap_create(struct mddev
*mddev
)
1671 struct bitmap
*bitmap
;
1672 sector_t blocks
= mddev
->resync_max_sectors
;
1673 unsigned long chunks
;
1674 unsigned long pages
;
1675 struct file
*file
= mddev
->bitmap_info
.file
;
1677 struct sysfs_dirent
*bm
= NULL
;
1679 BUILD_BUG_ON(sizeof(bitmap_super_t
) != 256);
1681 BUG_ON(file
&& mddev
->bitmap_info
.offset
);
1683 bitmap
= kzalloc(sizeof(*bitmap
), GFP_KERNEL
);
1687 spin_lock_init(&bitmap
->lock
);
1688 atomic_set(&bitmap
->pending_writes
, 0);
1689 init_waitqueue_head(&bitmap
->write_wait
);
1690 init_waitqueue_head(&bitmap
->overflow_wait
);
1691 init_waitqueue_head(&bitmap
->behind_wait
);
1693 bitmap
->mddev
= mddev
;
1696 bm
= sysfs_get_dirent(mddev
->kobj
.sd
, NULL
, "bitmap");
1698 bitmap
->sysfs_can_clear
= sysfs_get_dirent(bm
, NULL
, "can_clear");
1701 bitmap
->sysfs_can_clear
= NULL
;
1703 bitmap
->file
= file
;
1706 /* As future accesses to this file will use bmap,
1707 * and bypass the page cache, we must sync the file
1712 /* read superblock from bitmap file (this sets mddev->bitmap_info.chunksize) */
1713 if (!mddev
->bitmap_info
.external
) {
1715 * If 'MD_ARRAY_FIRST_USE' is set, then device-mapper is
1716 * instructing us to create a new on-disk bitmap instance.
1718 if (test_and_clear_bit(MD_ARRAY_FIRST_USE
, &mddev
->flags
))
1719 err
= bitmap_new_disk_sb(bitmap
);
1721 err
= bitmap_read_sb(bitmap
);
1724 if (mddev
->bitmap_info
.chunksize
== 0 ||
1725 mddev
->bitmap_info
.daemon_sleep
== 0)
1726 /* chunksize and time_base need to be
1733 bitmap
->daemon_lastrun
= jiffies
;
1734 bitmap
->chunkshift
= (ffz(~mddev
->bitmap_info
.chunksize
)
1735 - BITMAP_BLOCK_SHIFT
);
1737 chunks
= (blocks
+ (1 << bitmap
->chunkshift
) - 1) >>
1739 pages
= (chunks
+ PAGE_COUNTER_RATIO
- 1) / PAGE_COUNTER_RATIO
;
1743 bitmap
->chunks
= chunks
;
1744 bitmap
->pages
= pages
;
1745 bitmap
->missing_pages
= pages
;
1747 bitmap
->bp
= kzalloc(pages
* sizeof(*bitmap
->bp
), GFP_KERNEL
);
1753 printk(KERN_INFO
"created bitmap (%lu pages) for device %s\n",
1754 pages
, bmname(bitmap
));
1756 mddev
->bitmap
= bitmap
;
1759 return (bitmap
->flags
& BITMAP_WRITE_ERROR
) ? -EIO
: 0;
1762 bitmap_free(bitmap
);
1766 int bitmap_load(struct mddev
*mddev
)
1770 sector_t sector
= 0;
1771 struct bitmap
*bitmap
= mddev
->bitmap
;
1776 /* Clear out old bitmap info first: Either there is none, or we
1777 * are resuming after someone else has possibly changed things,
1778 * so we should forget old cached info.
1779 * All chunks should be clean, but some might need_sync.
1781 while (sector
< mddev
->resync_max_sectors
) {
1783 bitmap_start_sync(bitmap
, sector
, &blocks
, 0);
1786 bitmap_close_sync(bitmap
);
1788 if (mddev
->degraded
== 0
1789 || bitmap
->events_cleared
== mddev
->events
)
1790 /* no need to keep dirty bits to optimise a
1791 * re-add of a missing device */
1792 start
= mddev
->recovery_cp
;
1794 mutex_lock(&mddev
->bitmap_info
.mutex
);
1795 err
= bitmap_init_from_disk(bitmap
, start
);
1796 mutex_unlock(&mddev
->bitmap_info
.mutex
);
1800 bitmap_mask_state(bitmap
, BITMAP_STALE
, MASK_UNSET
);
1802 /* Kick recovery in case any bits were set */
1803 set_bit(MD_RECOVERY_NEEDED
, &bitmap
->mddev
->recovery
);
1805 mddev
->thread
->timeout
= mddev
->bitmap_info
.daemon_sleep
;
1806 md_wakeup_thread(mddev
->thread
);
1808 bitmap_update_sb(bitmap
);
1810 if (bitmap
->flags
& BITMAP_WRITE_ERROR
)
1815 EXPORT_SYMBOL_GPL(bitmap_load
);
1817 void bitmap_status(struct seq_file
*seq
, struct bitmap
*bitmap
)
1819 unsigned long chunk_kb
;
1820 unsigned long flags
;
1825 spin_lock_irqsave(&bitmap
->lock
, flags
);
1826 chunk_kb
= bitmap
->mddev
->bitmap_info
.chunksize
>> 10;
1827 seq_printf(seq
, "bitmap: %lu/%lu pages [%luKB], "
1829 bitmap
->pages
- bitmap
->missing_pages
,
1831 (bitmap
->pages
- bitmap
->missing_pages
)
1832 << (PAGE_SHIFT
- 10),
1833 chunk_kb
? chunk_kb
: bitmap
->mddev
->bitmap_info
.chunksize
,
1834 chunk_kb
? "KB" : "B");
1836 seq_printf(seq
, ", file: ");
1837 seq_path(seq
, &bitmap
->file
->f_path
, " \t\n");
1840 seq_printf(seq
, "\n");
1841 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
1845 location_show(struct mddev
*mddev
, char *page
)
1848 if (mddev
->bitmap_info
.file
)
1849 len
= sprintf(page
, "file");
1850 else if (mddev
->bitmap_info
.offset
)
1851 len
= sprintf(page
, "%+lld", (long long)mddev
->bitmap_info
.offset
);
1853 len
= sprintf(page
, "none");
1854 len
+= sprintf(page
+len
, "\n");
1859 location_store(struct mddev
*mddev
, const char *buf
, size_t len
)
1863 if (!mddev
->pers
->quiesce
)
1865 if (mddev
->recovery
|| mddev
->sync_thread
)
1869 if (mddev
->bitmap
|| mddev
->bitmap_info
.file
||
1870 mddev
->bitmap_info
.offset
) {
1871 /* bitmap already configured. Only option is to clear it */
1872 if (strncmp(buf
, "none", 4) != 0)
1875 mddev
->pers
->quiesce(mddev
, 1);
1876 bitmap_destroy(mddev
);
1877 mddev
->pers
->quiesce(mddev
, 0);
1879 mddev
->bitmap_info
.offset
= 0;
1880 if (mddev
->bitmap_info
.file
) {
1881 struct file
*f
= mddev
->bitmap_info
.file
;
1882 mddev
->bitmap_info
.file
= NULL
;
1883 restore_bitmap_write_access(f
);
1887 /* No bitmap, OK to set a location */
1889 if (strncmp(buf
, "none", 4) == 0)
1890 /* nothing to be done */;
1891 else if (strncmp(buf
, "file:", 5) == 0) {
1892 /* Not supported yet */
1897 rv
= strict_strtoll(buf
+1, 10, &offset
);
1899 rv
= strict_strtoll(buf
, 10, &offset
);
1904 if (mddev
->bitmap_info
.external
== 0 &&
1905 mddev
->major_version
== 0 &&
1906 offset
!= mddev
->bitmap_info
.default_offset
)
1908 mddev
->bitmap_info
.offset
= offset
;
1910 mddev
->pers
->quiesce(mddev
, 1);
1911 rv
= bitmap_create(mddev
);
1913 rv
= bitmap_load(mddev
);
1915 bitmap_destroy(mddev
);
1916 mddev
->bitmap_info
.offset
= 0;
1918 mddev
->pers
->quiesce(mddev
, 0);
1924 if (!mddev
->external
) {
1925 /* Ensure new bitmap info is stored in
1926 * metadata promptly.
1928 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
1929 md_wakeup_thread(mddev
->thread
);
1934 static struct md_sysfs_entry bitmap_location
=
1935 __ATTR(location
, S_IRUGO
|S_IWUSR
, location_show
, location_store
);
1937 /* 'bitmap/space' is the space available at 'location' for the
1938 * bitmap. This allows the kernel to know when it is safe to
1939 * resize the bitmap to match a resized array.
1942 space_show(struct mddev
*mddev
, char *page
)
1944 return sprintf(page
, "%lu\n", mddev
->bitmap_info
.space
);
1948 space_store(struct mddev
*mddev
, const char *buf
, size_t len
)
1950 unsigned long sectors
;
1953 rv
= kstrtoul(buf
, 10, §ors
);
1960 if (mddev
->bitmap
&&
1961 sectors
< ((mddev
->bitmap
->file_pages
- 1) * PAGE_SIZE
1962 + mddev
->bitmap
->last_page_size
+ 511) >> 9)
1963 return -EFBIG
; /* Bitmap is too big for this small space */
1965 /* could make sure it isn't too big, but that isn't really
1966 * needed - user-space should be careful.
1968 mddev
->bitmap_info
.space
= sectors
;
1972 static struct md_sysfs_entry bitmap_space
=
1973 __ATTR(space
, S_IRUGO
|S_IWUSR
, space_show
, space_store
);
1976 timeout_show(struct mddev
*mddev
, char *page
)
1979 unsigned long secs
= mddev
->bitmap_info
.daemon_sleep
/ HZ
;
1980 unsigned long jifs
= mddev
->bitmap_info
.daemon_sleep
% HZ
;
1982 len
= sprintf(page
, "%lu", secs
);
1984 len
+= sprintf(page
+len
, ".%03u", jiffies_to_msecs(jifs
));
1985 len
+= sprintf(page
+len
, "\n");
1990 timeout_store(struct mddev
*mddev
, const char *buf
, size_t len
)
1992 /* timeout can be set at any time */
1993 unsigned long timeout
;
1994 int rv
= strict_strtoul_scaled(buf
, &timeout
, 4);
1998 /* just to make sure we don't overflow... */
1999 if (timeout
>= LONG_MAX
/ HZ
)
2002 timeout
= timeout
* HZ
/ 10000;
2004 if (timeout
>= MAX_SCHEDULE_TIMEOUT
)
2005 timeout
= MAX_SCHEDULE_TIMEOUT
-1;
2008 mddev
->bitmap_info
.daemon_sleep
= timeout
;
2009 if (mddev
->thread
) {
2010 /* if thread->timeout is MAX_SCHEDULE_TIMEOUT, then
2011 * the bitmap is all clean and we don't need to
2012 * adjust the timeout right now
2014 if (mddev
->thread
->timeout
< MAX_SCHEDULE_TIMEOUT
) {
2015 mddev
->thread
->timeout
= timeout
;
2016 md_wakeup_thread(mddev
->thread
);
2022 static struct md_sysfs_entry bitmap_timeout
=
2023 __ATTR(time_base
, S_IRUGO
|S_IWUSR
, timeout_show
, timeout_store
);
2026 backlog_show(struct mddev
*mddev
, char *page
)
2028 return sprintf(page
, "%lu\n", mddev
->bitmap_info
.max_write_behind
);
2032 backlog_store(struct mddev
*mddev
, const char *buf
, size_t len
)
2034 unsigned long backlog
;
2035 int rv
= strict_strtoul(buf
, 10, &backlog
);
2038 if (backlog
> COUNTER_MAX
)
2040 mddev
->bitmap_info
.max_write_behind
= backlog
;
2044 static struct md_sysfs_entry bitmap_backlog
=
2045 __ATTR(backlog
, S_IRUGO
|S_IWUSR
, backlog_show
, backlog_store
);
2048 chunksize_show(struct mddev
*mddev
, char *page
)
2050 return sprintf(page
, "%lu\n", mddev
->bitmap_info
.chunksize
);
2054 chunksize_store(struct mddev
*mddev
, const char *buf
, size_t len
)
2056 /* Can only be changed when no bitmap is active */
2058 unsigned long csize
;
2061 rv
= strict_strtoul(buf
, 10, &csize
);
2065 !is_power_of_2(csize
))
2067 mddev
->bitmap_info
.chunksize
= csize
;
2071 static struct md_sysfs_entry bitmap_chunksize
=
2072 __ATTR(chunksize
, S_IRUGO
|S_IWUSR
, chunksize_show
, chunksize_store
);
2074 static ssize_t
metadata_show(struct mddev
*mddev
, char *page
)
2076 return sprintf(page
, "%s\n", (mddev
->bitmap_info
.external
2077 ? "external" : "internal"));
2080 static ssize_t
metadata_store(struct mddev
*mddev
, const char *buf
, size_t len
)
2082 if (mddev
->bitmap
||
2083 mddev
->bitmap_info
.file
||
2084 mddev
->bitmap_info
.offset
)
2086 if (strncmp(buf
, "external", 8) == 0)
2087 mddev
->bitmap_info
.external
= 1;
2088 else if (strncmp(buf
, "internal", 8) == 0)
2089 mddev
->bitmap_info
.external
= 0;
2095 static struct md_sysfs_entry bitmap_metadata
=
2096 __ATTR(metadata
, S_IRUGO
|S_IWUSR
, metadata_show
, metadata_store
);
2098 static ssize_t
can_clear_show(struct mddev
*mddev
, char *page
)
2102 len
= sprintf(page
, "%s\n", (mddev
->bitmap
->need_sync
?
2105 len
= sprintf(page
, "\n");
2109 static ssize_t
can_clear_store(struct mddev
*mddev
, const char *buf
, size_t len
)
2111 if (mddev
->bitmap
== NULL
)
2113 if (strncmp(buf
, "false", 5) == 0)
2114 mddev
->bitmap
->need_sync
= 1;
2115 else if (strncmp(buf
, "true", 4) == 0) {
2116 if (mddev
->degraded
)
2118 mddev
->bitmap
->need_sync
= 0;
2124 static struct md_sysfs_entry bitmap_can_clear
=
2125 __ATTR(can_clear
, S_IRUGO
|S_IWUSR
, can_clear_show
, can_clear_store
);
2128 behind_writes_used_show(struct mddev
*mddev
, char *page
)
2130 if (mddev
->bitmap
== NULL
)
2131 return sprintf(page
, "0\n");
2132 return sprintf(page
, "%lu\n",
2133 mddev
->bitmap
->behind_writes_used
);
2137 behind_writes_used_reset(struct mddev
*mddev
, const char *buf
, size_t len
)
2140 mddev
->bitmap
->behind_writes_used
= 0;
2144 static struct md_sysfs_entry max_backlog_used
=
2145 __ATTR(max_backlog_used
, S_IRUGO
| S_IWUSR
,
2146 behind_writes_used_show
, behind_writes_used_reset
);
2148 static struct attribute
*md_bitmap_attrs
[] = {
2149 &bitmap_location
.attr
,
2151 &bitmap_timeout
.attr
,
2152 &bitmap_backlog
.attr
,
2153 &bitmap_chunksize
.attr
,
2154 &bitmap_metadata
.attr
,
2155 &bitmap_can_clear
.attr
,
2156 &max_backlog_used
.attr
,
2159 struct attribute_group md_bitmap_group
= {
2161 .attrs
= md_bitmap_attrs
,