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).
16 * wait if count gets too high, wake when it drops to half.
19 #include <linux/blkdev.h>
20 #include <linux/module.h>
21 #include <linux/errno.h>
22 #include <linux/slab.h>
23 #include <linux/init.h>
24 #include <linux/timer.h>
25 #include <linux/sched.h>
26 #include <linux/list.h>
27 #include <linux/file.h>
28 #include <linux/mount.h>
29 #include <linux/buffer_head.h>
38 /* these are for debugging purposes only! */
40 /* define one and only one of these */
41 #define INJECT_FAULTS_1 0 /* cause bitmap_alloc_page to fail always */
42 #define INJECT_FAULTS_2 0 /* cause bitmap file to be kicked when first bit set*/
43 #define INJECT_FAULTS_3 0 /* treat bitmap file as kicked at init time */
44 #define INJECT_FAULTS_4 0 /* undef */
45 #define INJECT_FAULTS_5 0 /* undef */
46 #define INJECT_FAULTS_6 0
48 /* if these are defined, the driver will fail! debug only */
49 #define INJECT_FATAL_FAULT_1 0 /* fail kmalloc, causing bitmap_create to fail */
50 #define INJECT_FATAL_FAULT_2 0 /* undef */
51 #define INJECT_FATAL_FAULT_3 0 /* undef */
54 //#define DPRINTK PRINTK /* set this NULL to avoid verbose debug output */
55 #define DPRINTK(x...) do { } while(0)
59 # define PRINTK(x...) printk(KERN_DEBUG x)
65 static inline char * bmname(struct bitmap
*bitmap
)
67 return bitmap
->mddev
? mdname(bitmap
->mddev
) : "mdX";
72 * just a placeholder - calls kmalloc for bitmap pages
74 static unsigned char *bitmap_alloc_page(struct bitmap
*bitmap
)
78 #ifdef INJECT_FAULTS_1
81 page
= kmalloc(PAGE_SIZE
, GFP_NOIO
);
84 printk("%s: bitmap_alloc_page FAILED\n", bmname(bitmap
));
86 PRINTK("%s: bitmap_alloc_page: allocated page at %p\n",
87 bmname(bitmap
), page
);
92 * for now just a placeholder -- just calls kfree for bitmap pages
94 static void bitmap_free_page(struct bitmap
*bitmap
, unsigned char *page
)
96 PRINTK("%s: bitmap_free_page: free page %p\n", bmname(bitmap
), page
);
101 * check a page and, if necessary, allocate it (or hijack it if the alloc fails)
103 * 1) check to see if this page is allocated, if it's not then try to alloc
104 * 2) if the alloc fails, set the page's hijacked flag so we'll use the
105 * page pointer directly as a counter
107 * if we find our page, we increment the page's refcount so that it stays
108 * allocated while we're using it
110 static int bitmap_checkpage(struct bitmap
*bitmap
, unsigned long page
, int create
)
111 __releases(bitmap
->lock
)
112 __acquires(bitmap
->lock
)
114 unsigned char *mappage
;
116 if (page
>= bitmap
->pages
) {
117 /* This can happen if bitmap_start_sync goes beyond
118 * End-of-device while looking for a whole page.
125 if (bitmap
->bp
[page
].hijacked
) /* it's hijacked, don't try to alloc */
128 if (bitmap
->bp
[page
].map
) /* page is already allocated, just return */
134 spin_unlock_irq(&bitmap
->lock
);
136 /* this page has not been allocated yet */
138 if ((mappage
= bitmap_alloc_page(bitmap
)) == NULL
) {
139 PRINTK("%s: bitmap map page allocation failed, hijacking\n",
141 /* failed - set the hijacked flag so that we can use the
142 * pointer as a counter */
143 spin_lock_irq(&bitmap
->lock
);
144 if (!bitmap
->bp
[page
].map
)
145 bitmap
->bp
[page
].hijacked
= 1;
151 spin_lock_irq(&bitmap
->lock
);
153 /* recheck the page */
155 if (bitmap
->bp
[page
].map
|| bitmap
->bp
[page
].hijacked
) {
156 /* somebody beat us to getting the page */
157 bitmap_free_page(bitmap
, mappage
);
161 /* no page was in place and we have one, so install it */
163 memset(mappage
, 0, PAGE_SIZE
);
164 bitmap
->bp
[page
].map
= mappage
;
165 bitmap
->missing_pages
--;
171 /* if page is completely empty, put it back on the free list, or dealloc it */
172 /* if page was hijacked, unmark the flag so it might get alloced next time */
173 /* Note: lock should be held when calling this */
174 static void bitmap_checkfree(struct bitmap
*bitmap
, unsigned long page
)
178 if (bitmap
->bp
[page
].count
) /* page is still busy */
181 /* page is no longer in use, it can be released */
183 if (bitmap
->bp
[page
].hijacked
) { /* page was hijacked, undo this now */
184 bitmap
->bp
[page
].hijacked
= 0;
185 bitmap
->bp
[page
].map
= NULL
;
189 /* normal case, free the page */
192 /* actually ... let's not. We will probably need the page again exactly when
193 * memory is tight and we are flusing to disk
197 ptr
= bitmap
->bp
[page
].map
;
198 bitmap
->bp
[page
].map
= NULL
;
199 bitmap
->missing_pages
++;
200 bitmap_free_page(bitmap
, ptr
);
207 * bitmap file handling - read and write the bitmap file and its superblock
211 * basic page I/O operations
214 /* IO operations when bitmap is stored near all superblocks */
215 static struct page
*read_sb_page(mddev_t
*mddev
, loff_t offset
,
217 unsigned long index
, int size
)
219 /* choose a good rdev and read the page from there */
225 page
= alloc_page(GFP_KERNEL
);
227 return ERR_PTR(-ENOMEM
);
229 list_for_each_entry(rdev
, &mddev
->disks
, same_set
) {
230 if (! test_bit(In_sync
, &rdev
->flags
)
231 || test_bit(Faulty
, &rdev
->flags
))
234 target
= rdev
->sb_start
+ offset
+ index
* (PAGE_SIZE
/512);
236 if (sync_page_io(rdev
->bdev
, target
,
237 roundup(size
, bdev_logical_block_size(rdev
->bdev
)),
240 attach_page_buffers(page
, NULL
); /* so that free_buffer will
245 return ERR_PTR(-EIO
);
249 static mdk_rdev_t
*next_active_rdev(mdk_rdev_t
*rdev
, mddev_t
*mddev
)
251 /* Iterate the disks of an mddev, using rcu to protect access to the
252 * linked list, and raising the refcount of devices we return to ensure
253 * they don't disappear while in use.
254 * As devices are only added or removed when raid_disk is < 0 and
255 * nr_pending is 0 and In_sync is clear, the entries we return will
256 * still be in the same position on the list when we re-enter
257 * list_for_each_continue_rcu.
259 struct list_head
*pos
;
262 /* start at the beginning */
265 /* release the previous rdev and start from there. */
266 rdev_dec_pending(rdev
, mddev
);
267 pos
= &rdev
->same_set
;
269 list_for_each_continue_rcu(pos
, &mddev
->disks
) {
270 rdev
= list_entry(pos
, mdk_rdev_t
, same_set
);
271 if (rdev
->raid_disk
>= 0 &&
272 !test_bit(Faulty
, &rdev
->flags
)) {
273 /* this is a usable devices */
274 atomic_inc(&rdev
->nr_pending
);
283 static int write_sb_page(struct bitmap
*bitmap
, struct page
*page
, int wait
)
285 mdk_rdev_t
*rdev
= NULL
;
286 mddev_t
*mddev
= bitmap
->mddev
;
288 while ((rdev
= next_active_rdev(rdev
, mddev
)) != NULL
) {
289 int size
= PAGE_SIZE
;
290 loff_t offset
= mddev
->bitmap_info
.offset
;
291 if (page
->index
== bitmap
->file_pages
-1)
292 size
= roundup(bitmap
->last_page_size
,
293 bdev_logical_block_size(rdev
->bdev
));
294 /* Just make sure we aren't corrupting data or
297 if (mddev
->external
) {
298 /* Bitmap could be anywhere. */
299 if (rdev
->sb_start
+ offset
+ (page
->index
*(PAGE_SIZE
/512)) >
301 rdev
->sb_start
+ offset
<
302 rdev
->data_offset
+ mddev
->dev_sectors
+
305 } else if (offset
< 0) {
306 /* DATA BITMAP METADATA */
308 + (long)(page
->index
* (PAGE_SIZE
/512))
310 /* bitmap runs in to metadata */
312 if (rdev
->data_offset
+ mddev
->dev_sectors
313 > rdev
->sb_start
+ offset
)
314 /* data runs in to bitmap */
316 } else if (rdev
->sb_start
< rdev
->data_offset
) {
317 /* METADATA BITMAP DATA */
320 + page
->index
*(PAGE_SIZE
/512) + size
/512
322 /* bitmap runs in to data */
325 /* DATA METADATA BITMAP - no problems */
327 md_super_write(mddev
, rdev
,
328 rdev
->sb_start
+ offset
329 + page
->index
* (PAGE_SIZE
/512),
335 md_super_wait(mddev
);
342 static void bitmap_file_kick(struct bitmap
*bitmap
);
344 * write out a page to a file
346 static void write_page(struct bitmap
*bitmap
, struct page
*page
, int wait
)
348 struct buffer_head
*bh
;
350 if (bitmap
->file
== NULL
) {
351 switch (write_sb_page(bitmap
, page
, wait
)) {
353 bitmap
->flags
|= BITMAP_WRITE_ERROR
;
357 bh
= page_buffers(page
);
359 while (bh
&& bh
->b_blocknr
) {
360 atomic_inc(&bitmap
->pending_writes
);
361 set_buffer_locked(bh
);
362 set_buffer_mapped(bh
);
363 submit_bh(WRITE
, bh
);
364 bh
= bh
->b_this_page
;
368 wait_event(bitmap
->write_wait
,
369 atomic_read(&bitmap
->pending_writes
)==0);
372 if (bitmap
->flags
& BITMAP_WRITE_ERROR
)
373 bitmap_file_kick(bitmap
);
376 static void end_bitmap_write(struct buffer_head
*bh
, int uptodate
)
378 struct bitmap
*bitmap
= bh
->b_private
;
382 spin_lock_irqsave(&bitmap
->lock
, flags
);
383 bitmap
->flags
|= BITMAP_WRITE_ERROR
;
384 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
386 if (atomic_dec_and_test(&bitmap
->pending_writes
))
387 wake_up(&bitmap
->write_wait
);
390 /* copied from buffer.c */
392 __clear_page_buffers(struct page
*page
)
394 ClearPagePrivate(page
);
395 set_page_private(page
, 0);
396 page_cache_release(page
);
398 static void free_buffers(struct page
*page
)
400 struct buffer_head
*bh
= page_buffers(page
);
403 struct buffer_head
*next
= bh
->b_this_page
;
404 free_buffer_head(bh
);
407 __clear_page_buffers(page
);
411 /* read a page from a file.
412 * We both read the page, and attach buffers to the page to record the
413 * address of each block (using bmap). These addresses will be used
414 * to write the block later, completely bypassing the filesystem.
415 * This usage is similar to how swap files are handled, and allows us
416 * to write to a file with no concerns of memory allocation failing.
418 static struct page
*read_page(struct file
*file
, unsigned long index
,
419 struct bitmap
*bitmap
,
422 struct page
*page
= NULL
;
423 struct inode
*inode
= file
->f_path
.dentry
->d_inode
;
424 struct buffer_head
*bh
;
427 PRINTK("read bitmap file (%dB @ %Lu)\n", (int)PAGE_SIZE
,
428 (unsigned long long)index
<< PAGE_SHIFT
);
430 page
= alloc_page(GFP_KERNEL
);
432 page
= ERR_PTR(-ENOMEM
);
436 bh
= alloc_page_buffers(page
, 1<<inode
->i_blkbits
, 0);
439 page
= ERR_PTR(-ENOMEM
);
442 attach_page_buffers(page
, bh
);
443 block
= index
<< (PAGE_SHIFT
- inode
->i_blkbits
);
448 bh
->b_blocknr
= bmap(inode
, block
);
449 if (bh
->b_blocknr
== 0) {
450 /* Cannot use this file! */
452 page
= ERR_PTR(-EINVAL
);
455 bh
->b_bdev
= inode
->i_sb
->s_bdev
;
456 if (count
< (1<<inode
->i_blkbits
))
459 count
-= (1<<inode
->i_blkbits
);
461 bh
->b_end_io
= end_bitmap_write
;
462 bh
->b_private
= bitmap
;
463 atomic_inc(&bitmap
->pending_writes
);
464 set_buffer_locked(bh
);
465 set_buffer_mapped(bh
);
469 bh
= bh
->b_this_page
;
473 wait_event(bitmap
->write_wait
,
474 atomic_read(&bitmap
->pending_writes
)==0);
475 if (bitmap
->flags
& BITMAP_WRITE_ERROR
) {
477 page
= ERR_PTR(-EIO
);
481 printk(KERN_ALERT
"md: bitmap read error: (%dB @ %Lu): %ld\n",
483 (unsigned long long)index
<< PAGE_SHIFT
,
489 * bitmap file superblock operations
492 /* update the event counter and sync the superblock to disk */
493 void bitmap_update_sb(struct bitmap
*bitmap
)
498 if (!bitmap
|| !bitmap
->mddev
) /* no bitmap for this array */
500 spin_lock_irqsave(&bitmap
->lock
, flags
);
501 if (!bitmap
->sb_page
) { /* no superblock */
502 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
505 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
506 sb
= (bitmap_super_t
*)kmap_atomic(bitmap
->sb_page
, KM_USER0
);
507 sb
->events
= cpu_to_le64(bitmap
->mddev
->events
);
508 if (bitmap
->mddev
->events
< bitmap
->events_cleared
) {
509 /* rocking back to read-only */
510 bitmap
->events_cleared
= bitmap
->mddev
->events
;
511 sb
->events_cleared
= cpu_to_le64(bitmap
->events_cleared
);
513 kunmap_atomic(sb
, KM_USER0
);
514 write_page(bitmap
, bitmap
->sb_page
, 1);
517 /* print out the bitmap file superblock */
518 void bitmap_print_sb(struct bitmap
*bitmap
)
522 if (!bitmap
|| !bitmap
->sb_page
)
524 sb
= (bitmap_super_t
*)kmap_atomic(bitmap
->sb_page
, KM_USER0
);
525 printk(KERN_DEBUG
"%s: bitmap file superblock:\n", bmname(bitmap
));
526 printk(KERN_DEBUG
" magic: %08x\n", le32_to_cpu(sb
->magic
));
527 printk(KERN_DEBUG
" version: %d\n", le32_to_cpu(sb
->version
));
528 printk(KERN_DEBUG
" uuid: %08x.%08x.%08x.%08x\n",
529 *(__u32
*)(sb
->uuid
+0),
530 *(__u32
*)(sb
->uuid
+4),
531 *(__u32
*)(sb
->uuid
+8),
532 *(__u32
*)(sb
->uuid
+12));
533 printk(KERN_DEBUG
" events: %llu\n",
534 (unsigned long long) le64_to_cpu(sb
->events
));
535 printk(KERN_DEBUG
"events cleared: %llu\n",
536 (unsigned long long) le64_to_cpu(sb
->events_cleared
));
537 printk(KERN_DEBUG
" state: %08x\n", le32_to_cpu(sb
->state
));
538 printk(KERN_DEBUG
" chunksize: %d B\n", le32_to_cpu(sb
->chunksize
));
539 printk(KERN_DEBUG
" daemon sleep: %ds\n", le32_to_cpu(sb
->daemon_sleep
));
540 printk(KERN_DEBUG
" sync size: %llu KB\n",
541 (unsigned long long)le64_to_cpu(sb
->sync_size
)/2);
542 printk(KERN_DEBUG
"max write behind: %d\n", le32_to_cpu(sb
->write_behind
));
543 kunmap_atomic(sb
, KM_USER0
);
546 /* read the superblock from the bitmap file and initialize some bitmap fields */
547 static int bitmap_read_sb(struct bitmap
*bitmap
)
551 unsigned long chunksize
, daemon_sleep
, write_behind
;
552 unsigned long long events
;
555 /* page 0 is the superblock, read it... */
557 loff_t isize
= i_size_read(bitmap
->file
->f_mapping
->host
);
558 int bytes
= isize
> PAGE_SIZE
? PAGE_SIZE
: isize
;
560 bitmap
->sb_page
= read_page(bitmap
->file
, 0, bitmap
, bytes
);
562 bitmap
->sb_page
= read_sb_page(bitmap
->mddev
,
563 bitmap
->mddev
->bitmap_info
.offset
,
565 0, sizeof(bitmap_super_t
));
567 if (IS_ERR(bitmap
->sb_page
)) {
568 err
= PTR_ERR(bitmap
->sb_page
);
569 bitmap
->sb_page
= NULL
;
573 sb
= (bitmap_super_t
*)kmap_atomic(bitmap
->sb_page
, KM_USER0
);
575 chunksize
= le32_to_cpu(sb
->chunksize
);
576 daemon_sleep
= le32_to_cpu(sb
->daemon_sleep
) * HZ
;
577 write_behind
= le32_to_cpu(sb
->write_behind
);
579 /* verify that the bitmap-specific fields are valid */
580 if (sb
->magic
!= cpu_to_le32(BITMAP_MAGIC
))
581 reason
= "bad magic";
582 else if (le32_to_cpu(sb
->version
) < BITMAP_MAJOR_LO
||
583 le32_to_cpu(sb
->version
) > BITMAP_MAJOR_HI
)
584 reason
= "unrecognized superblock version";
585 else if (chunksize
< 512)
586 reason
= "bitmap chunksize too small";
587 else if ((1 << ffz(~chunksize
)) != chunksize
)
588 reason
= "bitmap chunksize not a power of 2";
589 else if (daemon_sleep
< 1 || daemon_sleep
> MAX_SCHEDULE_TIMEOUT
)
590 reason
= "daemon sleep period out of range";
591 else if (write_behind
> COUNTER_MAX
)
592 reason
= "write-behind limit out of range (0 - 16383)";
594 printk(KERN_INFO
"%s: invalid bitmap file superblock: %s\n",
595 bmname(bitmap
), reason
);
599 /* keep the array size field of the bitmap superblock up to date */
600 sb
->sync_size
= cpu_to_le64(bitmap
->mddev
->resync_max_sectors
);
602 if (!bitmap
->mddev
->persistent
)
606 * if we have a persistent array superblock, compare the
607 * bitmap's UUID and event counter to the mddev's
609 if (memcmp(sb
->uuid
, bitmap
->mddev
->uuid
, 16)) {
610 printk(KERN_INFO
"%s: bitmap superblock UUID mismatch\n",
614 events
= le64_to_cpu(sb
->events
);
615 if (events
< bitmap
->mddev
->events
) {
616 printk(KERN_INFO
"%s: bitmap file is out of date (%llu < %llu) "
617 "-- forcing full recovery\n", bmname(bitmap
), events
,
618 (unsigned long long) bitmap
->mddev
->events
);
619 sb
->state
|= cpu_to_le32(BITMAP_STALE
);
622 /* assign fields using values from superblock */
623 bitmap
->mddev
->bitmap_info
.chunksize
= chunksize
;
624 bitmap
->mddev
->bitmap_info
.daemon_sleep
= daemon_sleep
;
625 bitmap
->daemon_lastrun
= jiffies
;
626 bitmap
->mddev
->bitmap_info
.max_write_behind
= write_behind
;
627 bitmap
->flags
|= le32_to_cpu(sb
->state
);
628 if (le32_to_cpu(sb
->version
) == BITMAP_MAJOR_HOSTENDIAN
)
629 bitmap
->flags
|= BITMAP_HOSTENDIAN
;
630 bitmap
->events_cleared
= le64_to_cpu(sb
->events_cleared
);
631 if (sb
->state
& cpu_to_le32(BITMAP_STALE
))
632 bitmap
->events_cleared
= bitmap
->mddev
->events
;
635 kunmap_atomic(sb
, KM_USER0
);
637 bitmap_print_sb(bitmap
);
641 enum bitmap_mask_op
{
646 /* record the state of the bitmap in the superblock. Return the old value */
647 static int bitmap_mask_state(struct bitmap
*bitmap
, enum bitmap_state bits
,
648 enum bitmap_mask_op op
)
654 spin_lock_irqsave(&bitmap
->lock
, flags
);
655 if (!bitmap
->sb_page
) { /* can't set the state */
656 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
659 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
660 sb
= (bitmap_super_t
*)kmap_atomic(bitmap
->sb_page
, KM_USER0
);
661 old
= le32_to_cpu(sb
->state
) & bits
;
663 case MASK_SET
: sb
->state
|= cpu_to_le32(bits
);
665 case MASK_UNSET
: sb
->state
&= cpu_to_le32(~bits
);
669 kunmap_atomic(sb
, KM_USER0
);
674 * general bitmap file operations
677 /* calculate the index of the page that contains this bit */
678 static inline unsigned long file_page_index(unsigned long chunk
)
680 return CHUNK_BIT_OFFSET(chunk
) >> PAGE_BIT_SHIFT
;
683 /* calculate the (bit) offset of this bit within a page */
684 static inline unsigned long file_page_offset(unsigned long chunk
)
686 return CHUNK_BIT_OFFSET(chunk
) & (PAGE_BITS
- 1);
690 * return a pointer to the page in the filemap that contains the given bit
692 * this lookup is complicated by the fact that the bitmap sb might be exactly
693 * 1 page (e.g., x86) or less than 1 page -- so the bitmap might start on page
696 static inline struct page
*filemap_get_page(struct bitmap
*bitmap
,
699 if (file_page_index(chunk
) >= bitmap
->file_pages
) return NULL
;
700 return bitmap
->filemap
[file_page_index(chunk
) - file_page_index(0)];
704 static void bitmap_file_unmap(struct bitmap
*bitmap
)
706 struct page
**map
, *sb_page
;
711 spin_lock_irqsave(&bitmap
->lock
, flags
);
712 map
= bitmap
->filemap
;
713 bitmap
->filemap
= NULL
;
714 attr
= bitmap
->filemap_attr
;
715 bitmap
->filemap_attr
= NULL
;
716 pages
= bitmap
->file_pages
;
717 bitmap
->file_pages
= 0;
718 sb_page
= bitmap
->sb_page
;
719 bitmap
->sb_page
= NULL
;
720 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
723 if (map
[pages
]->index
!= 0) /* 0 is sb_page, release it below */
724 free_buffers(map
[pages
]);
729 free_buffers(sb_page
);
732 static void bitmap_file_put(struct bitmap
*bitmap
)
737 spin_lock_irqsave(&bitmap
->lock
, flags
);
740 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
743 wait_event(bitmap
->write_wait
,
744 atomic_read(&bitmap
->pending_writes
)==0);
745 bitmap_file_unmap(bitmap
);
748 struct inode
*inode
= file
->f_path
.dentry
->d_inode
;
749 invalidate_mapping_pages(inode
->i_mapping
, 0, -1);
756 * bitmap_file_kick - if an error occurs while manipulating the bitmap file
757 * then it is no longer reliable, so we stop using it and we mark the file
758 * as failed in the superblock
760 static void bitmap_file_kick(struct bitmap
*bitmap
)
762 char *path
, *ptr
= NULL
;
764 if (bitmap_mask_state(bitmap
, BITMAP_STALE
, MASK_SET
) == 0) {
765 bitmap_update_sb(bitmap
);
768 path
= kmalloc(PAGE_SIZE
, GFP_KERNEL
);
770 ptr
= d_path(&bitmap
->file
->f_path
, path
,
775 "%s: kicking failed bitmap file %s from array!\n",
776 bmname(bitmap
), IS_ERR(ptr
) ? "" : ptr
);
781 "%s: disabling internal bitmap due to errors\n",
785 bitmap_file_put(bitmap
);
790 enum bitmap_page_attr
{
791 BITMAP_PAGE_DIRTY
= 0, // there are set bits that need to be synced
792 BITMAP_PAGE_CLEAN
= 1, // there are bits that might need to be cleared
793 BITMAP_PAGE_NEEDWRITE
=2, // there are cleared bits that need to be synced
796 static inline void set_page_attr(struct bitmap
*bitmap
, struct page
*page
,
797 enum bitmap_page_attr attr
)
799 __set_bit((page
->index
<<2) + attr
, bitmap
->filemap_attr
);
802 static inline void clear_page_attr(struct bitmap
*bitmap
, struct page
*page
,
803 enum bitmap_page_attr attr
)
805 __clear_bit((page
->index
<<2) + attr
, bitmap
->filemap_attr
);
808 static inline unsigned long test_page_attr(struct bitmap
*bitmap
, struct page
*page
,
809 enum bitmap_page_attr attr
)
811 return test_bit((page
->index
<<2) + attr
, bitmap
->filemap_attr
);
815 * bitmap_file_set_bit -- called before performing a write to the md device
816 * to set (and eventually sync) a particular bit in the bitmap file
818 * we set the bit immediately, then we record the page number so that
819 * when an unplug occurs, we can flush the dirty pages out to disk
821 static void bitmap_file_set_bit(struct bitmap
*bitmap
, sector_t block
)
826 unsigned long chunk
= block
>> CHUNK_BLOCK_SHIFT(bitmap
);
828 if (!bitmap
->filemap
) {
832 page
= filemap_get_page(bitmap
, chunk
);
834 bit
= file_page_offset(chunk
);
837 kaddr
= kmap_atomic(page
, KM_USER0
);
838 if (bitmap
->flags
& BITMAP_HOSTENDIAN
)
841 ext2_set_bit(bit
, kaddr
);
842 kunmap_atomic(kaddr
, KM_USER0
);
843 PRINTK("set file bit %lu page %lu\n", bit
, page
->index
);
845 /* record page number so it gets flushed to disk when unplug occurs */
846 set_page_attr(bitmap
, page
, BITMAP_PAGE_DIRTY
);
850 /* this gets called when the md device is ready to unplug its underlying
851 * (slave) device queues -- before we let any writes go down, we need to
852 * sync the dirty pages of the bitmap file to disk */
853 void bitmap_unplug(struct bitmap
*bitmap
)
855 unsigned long i
, flags
;
856 int dirty
, need_write
;
863 /* look at each page to see if there are any set bits that need to be
864 * flushed out to disk */
865 for (i
= 0; i
< bitmap
->file_pages
; i
++) {
866 spin_lock_irqsave(&bitmap
->lock
, flags
);
867 if (!bitmap
->filemap
) {
868 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
871 page
= bitmap
->filemap
[i
];
872 dirty
= test_page_attr(bitmap
, page
, BITMAP_PAGE_DIRTY
);
873 need_write
= test_page_attr(bitmap
, page
, BITMAP_PAGE_NEEDWRITE
);
874 clear_page_attr(bitmap
, page
, BITMAP_PAGE_DIRTY
);
875 clear_page_attr(bitmap
, page
, BITMAP_PAGE_NEEDWRITE
);
878 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
880 if (dirty
| need_write
)
881 write_page(bitmap
, page
, 0);
883 if (wait
) { /* if any writes were performed, we need to wait on them */
885 wait_event(bitmap
->write_wait
,
886 atomic_read(&bitmap
->pending_writes
)==0);
888 md_super_wait(bitmap
->mddev
);
890 if (bitmap
->flags
& BITMAP_WRITE_ERROR
)
891 bitmap_file_kick(bitmap
);
894 static void bitmap_set_memory_bits(struct bitmap
*bitmap
, sector_t offset
, int needed
);
895 /* * bitmap_init_from_disk -- called at bitmap_create time to initialize
896 * the in-memory bitmap from the on-disk bitmap -- also, sets up the
897 * memory mapping of the bitmap file
899 * if there's no bitmap file, or if the bitmap file had been
900 * previously kicked from the array, we mark all the bits as
901 * 1's in order to cause a full resync.
903 * We ignore all bits for sectors that end earlier than 'start'.
904 * This is used when reading an out-of-date bitmap...
906 static int bitmap_init_from_disk(struct bitmap
*bitmap
, sector_t start
)
908 unsigned long i
, chunks
, index
, oldindex
, bit
;
909 struct page
*page
= NULL
, *oldpage
= NULL
;
910 unsigned long num_pages
, bit_cnt
= 0;
912 unsigned long bytes
, offset
;
917 chunks
= bitmap
->chunks
;
920 BUG_ON(!file
&& !bitmap
->mddev
->bitmap_info
.offset
);
922 #ifdef INJECT_FAULTS_3
925 outofdate
= bitmap
->flags
& BITMAP_STALE
;
928 printk(KERN_INFO
"%s: bitmap file is out of date, doing full "
929 "recovery\n", bmname(bitmap
));
931 bytes
= (chunks
+ 7) / 8;
933 num_pages
= (bytes
+ sizeof(bitmap_super_t
) + PAGE_SIZE
- 1) / PAGE_SIZE
;
935 if (file
&& i_size_read(file
->f_mapping
->host
) < bytes
+ sizeof(bitmap_super_t
)) {
936 printk(KERN_INFO
"%s: bitmap file too short %lu < %lu\n",
938 (unsigned long) i_size_read(file
->f_mapping
->host
),
939 bytes
+ sizeof(bitmap_super_t
));
945 bitmap
->filemap
= kmalloc(sizeof(struct page
*) * num_pages
, GFP_KERNEL
);
946 if (!bitmap
->filemap
)
949 /* We need 4 bits per page, rounded up to a multiple of sizeof(unsigned long) */
950 bitmap
->filemap_attr
= kzalloc(
951 roundup( DIV_ROUND_UP(num_pages
*4, 8), sizeof(unsigned long)),
953 if (!bitmap
->filemap_attr
)
958 for (i
= 0; i
< chunks
; i
++) {
960 index
= file_page_index(i
);
961 bit
= file_page_offset(i
);
962 if (index
!= oldindex
) { /* this is a new page, read it in */
964 /* unmap the old page, we're done with it */
965 if (index
== num_pages
-1)
966 count
= bytes
+ sizeof(bitmap_super_t
)
972 * if we're here then the superblock page
973 * contains some bits (PAGE_SIZE != sizeof sb)
974 * we've already read it in, so just use it
976 page
= bitmap
->sb_page
;
977 offset
= sizeof(bitmap_super_t
);
979 read_sb_page(bitmap
->mddev
,
980 bitmap
->mddev
->bitmap_info
.offset
,
984 page
= read_page(file
, index
, bitmap
, count
);
987 page
= read_sb_page(bitmap
->mddev
,
988 bitmap
->mddev
->bitmap_info
.offset
,
993 if (IS_ERR(page
)) { /* read error */
1001 bitmap
->filemap
[bitmap
->file_pages
++] = page
;
1002 bitmap
->last_page_size
= count
;
1006 * if bitmap is out of date, dirty the
1007 * whole page and write it out
1009 paddr
= kmap_atomic(page
, KM_USER0
);
1010 memset(paddr
+ offset
, 0xff,
1011 PAGE_SIZE
- offset
);
1012 kunmap_atomic(paddr
, KM_USER0
);
1013 write_page(bitmap
, page
, 1);
1016 if (bitmap
->flags
& BITMAP_WRITE_ERROR
)
1020 paddr
= kmap_atomic(page
, KM_USER0
);
1021 if (bitmap
->flags
& BITMAP_HOSTENDIAN
)
1022 b
= test_bit(bit
, paddr
);
1024 b
= ext2_test_bit(bit
, paddr
);
1025 kunmap_atomic(paddr
, KM_USER0
);
1027 /* if the disk bit is set, set the memory bit */
1028 int needed
= ((sector_t
)(i
+1) << (CHUNK_BLOCK_SHIFT(bitmap
))
1030 bitmap_set_memory_bits(bitmap
,
1031 (sector_t
)i
<< CHUNK_BLOCK_SHIFT(bitmap
),
1034 set_page_attr(bitmap
, page
, BITMAP_PAGE_CLEAN
);
1038 /* everything went OK */
1040 bitmap_mask_state(bitmap
, BITMAP_STALE
, MASK_UNSET
);
1042 if (bit_cnt
) { /* Kick recovery if any bits were set */
1043 set_bit(MD_RECOVERY_NEEDED
, &bitmap
->mddev
->recovery
);
1044 md_wakeup_thread(bitmap
->mddev
->thread
);
1047 printk(KERN_INFO
"%s: bitmap initialized from disk: "
1048 "read %lu/%lu pages, set %lu bits\n",
1049 bmname(bitmap
), bitmap
->file_pages
, num_pages
, bit_cnt
);
1054 printk(KERN_INFO
"%s: bitmap initialisation failed: %d\n",
1055 bmname(bitmap
), ret
);
1059 void bitmap_write_all(struct bitmap
*bitmap
)
1061 /* We don't actually write all bitmap blocks here,
1062 * just flag them as needing to be written
1066 for (i
=0; i
< bitmap
->file_pages
; i
++)
1067 set_page_attr(bitmap
, bitmap
->filemap
[i
],
1068 BITMAP_PAGE_NEEDWRITE
);
1072 static void bitmap_count_page(struct bitmap
*bitmap
, sector_t offset
, int inc
)
1074 sector_t chunk
= offset
>> CHUNK_BLOCK_SHIFT(bitmap
);
1075 unsigned long page
= chunk
>> PAGE_COUNTER_SHIFT
;
1076 bitmap
->bp
[page
].count
+= inc
;
1078 if (page == 0) printk("count page 0, offset %llu: %d gives %d\n",
1079 (unsigned long long)offset, inc, bitmap->bp[page].count);
1081 bitmap_checkfree(bitmap
, page
);
1083 static bitmap_counter_t
*bitmap_get_counter(struct bitmap
*bitmap
,
1084 sector_t offset
, int *blocks
,
1088 * bitmap daemon -- periodically wakes up to clean bits and flush pages
1092 void bitmap_daemon_work(mddev_t
*mddev
)
1094 struct bitmap
*bitmap
;
1096 unsigned long flags
;
1097 struct page
*page
= NULL
, *lastpage
= NULL
;
1101 /* Use a mutex to guard daemon_work against
1104 mutex_lock(&mddev
->bitmap_info
.mutex
);
1105 bitmap
= mddev
->bitmap
;
1106 if (bitmap
== NULL
) {
1107 mutex_unlock(&mddev
->bitmap_info
.mutex
);
1110 if (time_before(jiffies
, bitmap
->daemon_lastrun
1111 + bitmap
->mddev
->bitmap_info
.daemon_sleep
))
1114 bitmap
->daemon_lastrun
= jiffies
;
1115 if (bitmap
->allclean
) {
1116 bitmap
->mddev
->thread
->timeout
= MAX_SCHEDULE_TIMEOUT
;
1119 bitmap
->allclean
= 1;
1121 spin_lock_irqsave(&bitmap
->lock
, flags
);
1122 for (j
= 0; j
< bitmap
->chunks
; j
++) {
1123 bitmap_counter_t
*bmc
;
1124 if (!bitmap
->filemap
)
1125 /* error or shutdown */
1128 page
= filemap_get_page(bitmap
, j
);
1130 if (page
!= lastpage
) {
1131 /* skip this page unless it's marked as needing cleaning */
1132 if (!test_page_attr(bitmap
, page
, BITMAP_PAGE_CLEAN
)) {
1133 int need_write
= test_page_attr(bitmap
, page
,
1134 BITMAP_PAGE_NEEDWRITE
);
1136 clear_page_attr(bitmap
, page
, BITMAP_PAGE_NEEDWRITE
);
1138 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
1140 write_page(bitmap
, page
, 0);
1141 bitmap
->allclean
= 0;
1143 spin_lock_irqsave(&bitmap
->lock
, flags
);
1144 j
|= (PAGE_BITS
- 1);
1148 /* grab the new page, sync and release the old */
1149 if (lastpage
!= NULL
) {
1150 if (test_page_attr(bitmap
, lastpage
, BITMAP_PAGE_NEEDWRITE
)) {
1151 clear_page_attr(bitmap
, lastpage
, BITMAP_PAGE_NEEDWRITE
);
1152 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
1153 write_page(bitmap
, lastpage
, 0);
1155 set_page_attr(bitmap
, lastpage
, BITMAP_PAGE_NEEDWRITE
);
1156 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
1159 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
1162 /* We are possibly going to clear some bits, so make
1163 * sure that events_cleared is up-to-date.
1165 if (bitmap
->need_sync
) {
1167 bitmap
->need_sync
= 0;
1168 sb
= kmap_atomic(bitmap
->sb_page
, KM_USER0
);
1169 sb
->events_cleared
=
1170 cpu_to_le64(bitmap
->events_cleared
);
1171 kunmap_atomic(sb
, KM_USER0
);
1172 write_page(bitmap
, bitmap
->sb_page
, 1);
1174 spin_lock_irqsave(&bitmap
->lock
, flags
);
1175 clear_page_attr(bitmap
, page
, BITMAP_PAGE_CLEAN
);
1177 bmc
= bitmap_get_counter(bitmap
,
1178 (sector_t
)j
<< CHUNK_BLOCK_SHIFT(bitmap
),
1182 if (j < 100) printk("bitmap: j=%lu, *bmc = 0x%x\n", j, *bmc);
1185 bitmap
->allclean
= 0;
1188 *bmc
=1; /* maybe clear the bit next time */
1189 set_page_attr(bitmap
, page
, BITMAP_PAGE_CLEAN
);
1190 } else if (*bmc
== 1) {
1191 /* we can clear the bit */
1193 bitmap_count_page(bitmap
,
1194 (sector_t
)j
<< CHUNK_BLOCK_SHIFT(bitmap
),
1198 paddr
= kmap_atomic(page
, KM_USER0
);
1199 if (bitmap
->flags
& BITMAP_HOSTENDIAN
)
1200 clear_bit(file_page_offset(j
), paddr
);
1202 ext2_clear_bit(file_page_offset(j
), paddr
);
1203 kunmap_atomic(paddr
, KM_USER0
);
1206 j
|= PAGE_COUNTER_MASK
;
1208 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
1210 /* now sync the final page */
1211 if (lastpage
!= NULL
) {
1212 spin_lock_irqsave(&bitmap
->lock
, flags
);
1213 if (test_page_attr(bitmap
, lastpage
, BITMAP_PAGE_NEEDWRITE
)) {
1214 clear_page_attr(bitmap
, lastpage
, BITMAP_PAGE_NEEDWRITE
);
1215 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
1216 write_page(bitmap
, lastpage
, 0);
1218 set_page_attr(bitmap
, lastpage
, BITMAP_PAGE_NEEDWRITE
);
1219 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
1224 if (bitmap
->allclean
== 0)
1225 bitmap
->mddev
->thread
->timeout
=
1226 bitmap
->mddev
->bitmap_info
.daemon_sleep
;
1227 mutex_unlock(&mddev
->bitmap_info
.mutex
);
1230 static bitmap_counter_t
*bitmap_get_counter(struct bitmap
*bitmap
,
1231 sector_t offset
, int *blocks
,
1233 __releases(bitmap
->lock
)
1234 __acquires(bitmap
->lock
)
1236 /* If 'create', we might release the lock and reclaim it.
1237 * The lock must have been taken with interrupts enabled.
1238 * If !create, we don't release the lock.
1240 sector_t chunk
= offset
>> CHUNK_BLOCK_SHIFT(bitmap
);
1241 unsigned long page
= chunk
>> PAGE_COUNTER_SHIFT
;
1242 unsigned long pageoff
= (chunk
& PAGE_COUNTER_MASK
) << COUNTER_BYTE_SHIFT
;
1245 if (bitmap_checkpage(bitmap
, page
, create
) < 0) {
1246 csize
= ((sector_t
)1) << (CHUNK_BLOCK_SHIFT(bitmap
));
1247 *blocks
= csize
- (offset
& (csize
- 1));
1250 /* now locked ... */
1252 if (bitmap
->bp
[page
].hijacked
) { /* hijacked pointer */
1253 /* should we use the first or second counter field
1254 * of the hijacked pointer? */
1255 int hi
= (pageoff
> PAGE_COUNTER_MASK
);
1256 csize
= ((sector_t
)1) << (CHUNK_BLOCK_SHIFT(bitmap
) +
1257 PAGE_COUNTER_SHIFT
- 1);
1258 *blocks
= csize
- (offset
& (csize
- 1));
1259 return &((bitmap_counter_t
*)
1260 &bitmap
->bp
[page
].map
)[hi
];
1261 } else { /* page is allocated */
1262 csize
= ((sector_t
)1) << (CHUNK_BLOCK_SHIFT(bitmap
));
1263 *blocks
= csize
- (offset
& (csize
- 1));
1264 return (bitmap_counter_t
*)
1265 &(bitmap
->bp
[page
].map
[pageoff
]);
1269 int bitmap_startwrite(struct bitmap
*bitmap
, sector_t offset
, unsigned long sectors
, int behind
)
1271 if (!bitmap
) return 0;
1274 atomic_inc(&bitmap
->behind_writes
);
1275 PRINTK(KERN_DEBUG
"inc write-behind count %d/%d\n",
1276 atomic_read(&bitmap
->behind_writes
), bitmap
->max_write_behind
);
1281 bitmap_counter_t
*bmc
;
1283 spin_lock_irq(&bitmap
->lock
);
1284 bmc
= bitmap_get_counter(bitmap
, offset
, &blocks
, 1);
1286 spin_unlock_irq(&bitmap
->lock
);
1290 if (unlikely((*bmc
& COUNTER_MAX
) == COUNTER_MAX
)) {
1291 DEFINE_WAIT(__wait
);
1292 /* note that it is safe to do the prepare_to_wait
1293 * after the test as long as we do it before dropping
1296 prepare_to_wait(&bitmap
->overflow_wait
, &__wait
,
1297 TASK_UNINTERRUPTIBLE
);
1298 spin_unlock_irq(&bitmap
->lock
);
1299 blk_unplug(bitmap
->mddev
->queue
);
1301 finish_wait(&bitmap
->overflow_wait
, &__wait
);
1307 bitmap_file_set_bit(bitmap
, offset
);
1308 bitmap_count_page(bitmap
,offset
, 1);
1309 blk_plug_device_unlocked(bitmap
->mddev
->queue
);
1317 spin_unlock_irq(&bitmap
->lock
);
1320 if (sectors
> blocks
)
1324 bitmap
->allclean
= 0;
1328 void bitmap_endwrite(struct bitmap
*bitmap
, sector_t offset
, unsigned long sectors
,
1329 int success
, int behind
)
1331 if (!bitmap
) return;
1333 atomic_dec(&bitmap
->behind_writes
);
1334 PRINTK(KERN_DEBUG
"dec write-behind count %d/%d\n",
1335 atomic_read(&bitmap
->behind_writes
), bitmap
->max_write_behind
);
1337 if (bitmap
->mddev
->degraded
)
1338 /* Never clear bits or update events_cleared when degraded */
1343 unsigned long flags
;
1344 bitmap_counter_t
*bmc
;
1346 spin_lock_irqsave(&bitmap
->lock
, flags
);
1347 bmc
= bitmap_get_counter(bitmap
, offset
, &blocks
, 0);
1349 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
1354 bitmap
->events_cleared
< bitmap
->mddev
->events
) {
1355 bitmap
->events_cleared
= bitmap
->mddev
->events
;
1356 bitmap
->need_sync
= 1;
1359 if (!success
&& ! (*bmc
& NEEDED_MASK
))
1360 *bmc
|= NEEDED_MASK
;
1362 if ((*bmc
& COUNTER_MAX
) == COUNTER_MAX
)
1363 wake_up(&bitmap
->overflow_wait
);
1367 set_page_attr(bitmap
,
1368 filemap_get_page(bitmap
, offset
>> CHUNK_BLOCK_SHIFT(bitmap
)),
1371 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
1373 if (sectors
> blocks
)
1379 static int __bitmap_start_sync(struct bitmap
*bitmap
, sector_t offset
, int *blocks
,
1382 bitmap_counter_t
*bmc
;
1384 if (bitmap
== NULL
) {/* FIXME or bitmap set as 'failed' */
1386 return 1; /* always resync if no bitmap */
1388 spin_lock_irq(&bitmap
->lock
);
1389 bmc
= bitmap_get_counter(bitmap
, offset
, blocks
, 0);
1395 else if (NEEDED(*bmc
)) {
1397 if (!degraded
) { /* don't set/clear bits if degraded */
1398 *bmc
|= RESYNC_MASK
;
1399 *bmc
&= ~NEEDED_MASK
;
1403 spin_unlock_irq(&bitmap
->lock
);
1404 bitmap
->allclean
= 0;
1408 int bitmap_start_sync(struct bitmap
*bitmap
, sector_t offset
, int *blocks
,
1411 /* bitmap_start_sync must always report on multiples of whole
1412 * pages, otherwise resync (which is very PAGE_SIZE based) will
1414 * So call __bitmap_start_sync repeatedly (if needed) until
1415 * At least PAGE_SIZE>>9 blocks are covered.
1416 * Return the 'or' of the result.
1422 while (*blocks
< (PAGE_SIZE
>>9)) {
1423 rv
|= __bitmap_start_sync(bitmap
, offset
,
1424 &blocks1
, degraded
);
1431 void bitmap_end_sync(struct bitmap
*bitmap
, sector_t offset
, int *blocks
, int aborted
)
1433 bitmap_counter_t
*bmc
;
1434 unsigned long flags
;
1436 if (offset == 0) printk("bitmap_end_sync 0 (%d)\n", aborted);
1437 */ if (bitmap
== NULL
) {
1441 spin_lock_irqsave(&bitmap
->lock
, flags
);
1442 bmc
= bitmap_get_counter(bitmap
, offset
, blocks
, 0);
1447 if (offset == 0) printk("bitmap_end sync found 0x%x, blocks %d\n", *bmc, *blocks);
1450 *bmc
&= ~RESYNC_MASK
;
1452 if (!NEEDED(*bmc
) && aborted
)
1453 *bmc
|= NEEDED_MASK
;
1456 set_page_attr(bitmap
,
1457 filemap_get_page(bitmap
, offset
>> CHUNK_BLOCK_SHIFT(bitmap
)),
1463 spin_unlock_irqrestore(&bitmap
->lock
, flags
);
1464 bitmap
->allclean
= 0;
1467 void bitmap_close_sync(struct bitmap
*bitmap
)
1469 /* Sync has finished, and any bitmap chunks that weren't synced
1470 * properly have been aborted. It remains to us to clear the
1471 * RESYNC bit wherever it is still on
1473 sector_t sector
= 0;
1477 while (sector
< bitmap
->mddev
->resync_max_sectors
) {
1478 bitmap_end_sync(bitmap
, sector
, &blocks
, 0);
1483 void bitmap_cond_end_sync(struct bitmap
*bitmap
, sector_t sector
)
1491 bitmap
->last_end_sync
= jiffies
;
1494 if (time_before(jiffies
, (bitmap
->last_end_sync
1495 + bitmap
->mddev
->bitmap_info
.daemon_sleep
)))
1497 wait_event(bitmap
->mddev
->recovery_wait
,
1498 atomic_read(&bitmap
->mddev
->recovery_active
) == 0);
1500 bitmap
->mddev
->curr_resync_completed
= bitmap
->mddev
->curr_resync
;
1501 set_bit(MD_CHANGE_CLEAN
, &bitmap
->mddev
->flags
);
1502 sector
&= ~((1ULL << CHUNK_BLOCK_SHIFT(bitmap
)) - 1);
1504 while (s
< sector
&& s
< bitmap
->mddev
->resync_max_sectors
) {
1505 bitmap_end_sync(bitmap
, s
, &blocks
, 0);
1508 bitmap
->last_end_sync
= jiffies
;
1509 sysfs_notify(&bitmap
->mddev
->kobj
, NULL
, "sync_completed");
1512 static void bitmap_set_memory_bits(struct bitmap
*bitmap
, sector_t offset
, int needed
)
1514 /* For each chunk covered by any of these sectors, set the
1515 * counter to 1 and set resync_needed. They should all
1516 * be 0 at this point
1520 bitmap_counter_t
*bmc
;
1521 spin_lock_irq(&bitmap
->lock
);
1522 bmc
= bitmap_get_counter(bitmap
, offset
, &secs
, 1);
1524 spin_unlock_irq(&bitmap
->lock
);
1529 *bmc
= 1 | (needed
?NEEDED_MASK
:0);
1530 bitmap_count_page(bitmap
, offset
, 1);
1531 page
= filemap_get_page(bitmap
, offset
>> CHUNK_BLOCK_SHIFT(bitmap
));
1532 set_page_attr(bitmap
, page
, BITMAP_PAGE_CLEAN
);
1534 spin_unlock_irq(&bitmap
->lock
);
1535 bitmap
->allclean
= 0;
1538 /* dirty the memory and file bits for bitmap chunks "s" to "e" */
1539 void bitmap_dirty_bits(struct bitmap
*bitmap
, unsigned long s
, unsigned long e
)
1541 unsigned long chunk
;
1543 for (chunk
= s
; chunk
<= e
; chunk
++) {
1544 sector_t sec
= (sector_t
)chunk
<< CHUNK_BLOCK_SHIFT(bitmap
);
1545 bitmap_set_memory_bits(bitmap
, sec
, 1);
1546 bitmap_file_set_bit(bitmap
, sec
);
1551 * flush out any pending updates
1553 void bitmap_flush(mddev_t
*mddev
)
1555 struct bitmap
*bitmap
= mddev
->bitmap
;
1558 if (!bitmap
) /* there was no bitmap */
1561 /* run the daemon_work three time to ensure everything is flushed
1564 sleep
= mddev
->bitmap_info
.daemon_sleep
* 2;
1565 bitmap
->daemon_lastrun
-= sleep
;
1566 bitmap_daemon_work(mddev
);
1567 bitmap
->daemon_lastrun
-= sleep
;
1568 bitmap_daemon_work(mddev
);
1569 bitmap
->daemon_lastrun
-= sleep
;
1570 bitmap_daemon_work(mddev
);
1571 bitmap_update_sb(bitmap
);
1575 * free memory that was allocated
1577 static void bitmap_free(struct bitmap
*bitmap
)
1579 unsigned long k
, pages
;
1580 struct bitmap_page
*bp
;
1582 if (!bitmap
) /* there was no bitmap */
1585 /* release the bitmap file and kill the daemon */
1586 bitmap_file_put(bitmap
);
1589 pages
= bitmap
->pages
;
1591 /* free all allocated memory */
1593 if (bp
) /* deallocate the page memory */
1594 for (k
= 0; k
< pages
; k
++)
1595 if (bp
[k
].map
&& !bp
[k
].hijacked
)
1601 void bitmap_destroy(mddev_t
*mddev
)
1603 struct bitmap
*bitmap
= mddev
->bitmap
;
1605 if (!bitmap
) /* there was no bitmap */
1608 mutex_lock(&mddev
->bitmap_info
.mutex
);
1609 mddev
->bitmap
= NULL
; /* disconnect from the md device */
1610 mutex_unlock(&mddev
->bitmap_info
.mutex
);
1612 mddev
->thread
->timeout
= MAX_SCHEDULE_TIMEOUT
;
1614 bitmap_free(bitmap
);
1618 * initialize the bitmap structure
1619 * if this returns an error, bitmap_destroy must be called to do clean up
1621 int bitmap_create(mddev_t
*mddev
)
1623 struct bitmap
*bitmap
;
1624 sector_t blocks
= mddev
->resync_max_sectors
;
1625 unsigned long chunks
;
1626 unsigned long pages
;
1627 struct file
*file
= mddev
->bitmap_info
.file
;
1631 BUILD_BUG_ON(sizeof(bitmap_super_t
) != 256);
1633 if (!file
&& !mddev
->bitmap_info
.offset
) /* bitmap disabled, nothing to do */
1636 BUG_ON(file
&& mddev
->bitmap_info
.offset
);
1638 bitmap
= kzalloc(sizeof(*bitmap
), GFP_KERNEL
);
1642 spin_lock_init(&bitmap
->lock
);
1643 atomic_set(&bitmap
->pending_writes
, 0);
1644 init_waitqueue_head(&bitmap
->write_wait
);
1645 init_waitqueue_head(&bitmap
->overflow_wait
);
1647 bitmap
->mddev
= mddev
;
1649 bitmap
->file
= file
;
1652 /* As future accesses to this file will use bmap,
1653 * and bypass the page cache, we must sync the file
1656 vfs_fsync(file
, file
->f_dentry
, 1);
1658 /* read superblock from bitmap file (this sets mddev->bitmap_info.chunksize) */
1659 err
= bitmap_read_sb(bitmap
);
1663 bitmap
->chunkshift
= ffz(~mddev
->bitmap_info
.chunksize
);
1665 /* now that chunksize and chunkshift are set, we can use these macros */
1666 chunks
= (blocks
+ CHUNK_BLOCK_RATIO(bitmap
) - 1) >>
1667 CHUNK_BLOCK_SHIFT(bitmap
);
1668 pages
= (chunks
+ PAGE_COUNTER_RATIO
- 1) / PAGE_COUNTER_RATIO
;
1672 bitmap
->chunks
= chunks
;
1673 bitmap
->pages
= pages
;
1674 bitmap
->missing_pages
= pages
;
1675 bitmap
->counter_bits
= COUNTER_BITS
;
1677 bitmap
->syncchunk
= ~0UL;
1679 #ifdef INJECT_FATAL_FAULT_1
1682 bitmap
->bp
= kzalloc(pages
* sizeof(*bitmap
->bp
), GFP_KERNEL
);
1688 /* now that we have some pages available, initialize the in-memory
1689 * bitmap from the on-disk bitmap */
1691 if (mddev
->degraded
== 0
1692 || bitmap
->events_cleared
== mddev
->events
)
1693 /* no need to keep dirty bits to optimise a re-add of a missing device */
1694 start
= mddev
->recovery_cp
;
1695 err
= bitmap_init_from_disk(bitmap
, start
);
1700 printk(KERN_INFO
"created bitmap (%lu pages) for device %s\n",
1701 pages
, bmname(bitmap
));
1703 mddev
->bitmap
= bitmap
;
1705 mddev
->thread
->timeout
= mddev
->bitmap_info
.daemon_sleep
;
1706 md_wakeup_thread(mddev
->thread
);
1708 bitmap_update_sb(bitmap
);
1710 return (bitmap
->flags
& BITMAP_WRITE_ERROR
) ? -EIO
: 0;
1713 bitmap_free(bitmap
);
1717 /* the bitmap API -- for raid personalities */
1718 EXPORT_SYMBOL(bitmap_startwrite
);
1719 EXPORT_SYMBOL(bitmap_endwrite
);
1720 EXPORT_SYMBOL(bitmap_start_sync
);
1721 EXPORT_SYMBOL(bitmap_end_sync
);
1722 EXPORT_SYMBOL(bitmap_unplug
);
1723 EXPORT_SYMBOL(bitmap_close_sync
);
1724 EXPORT_SYMBOL(bitmap_cond_end_sync
);