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>
32 #include <linux/dm-dirty-log.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 */
56 # define PRINTK(x...) printk(KERN_DEBUG x)
62 static inline char *bmname(struct bitmap *bitmap)
64 return bitmap->mddev ? mdname(bitmap->mddev) : "mdX";
68 * just a placeholder - calls kmalloc for bitmap pages
70 static unsigned char *bitmap_alloc_page(struct bitmap *bitmap)
74 #ifdef INJECT_FAULTS_1
77 page = kzalloc(PAGE_SIZE, GFP_NOIO);
80 printk("%s: bitmap_alloc_page FAILED\n", bmname(bitmap));
82 PRINTK("%s: bitmap_alloc_page: allocated page at %p\n",
83 bmname(bitmap), page);
88 * for now just a placeholder -- just calls kfree for bitmap pages
90 static void bitmap_free_page(struct bitmap *bitmap, unsigned char *page)
92 PRINTK("%s: bitmap_free_page: free page %p\n", bmname(bitmap), page);
97 * check a page and, if necessary, allocate it (or hijack it if the alloc fails)
99 * 1) check to see if this page is allocated, if it's not then try to alloc
100 * 2) if the alloc fails, set the page's hijacked flag so we'll use the
101 * page pointer directly as a counter
103 * if we find our page, we increment the page's refcount so that it stays
104 * allocated while we're using it
106 static int bitmap_checkpage(struct bitmap *bitmap,
107 unsigned long page, int create)
108 __releases(bitmap->lock)
109 __acquires(bitmap->lock)
111 unsigned char *mappage;
113 if (page >= bitmap->pages) {
114 /* This can happen if bitmap_start_sync goes beyond
115 * End-of-device while looking for a whole page.
121 if (bitmap->bp[page].hijacked) /* it's hijacked, don't try to alloc */
124 if (bitmap->bp[page].map) /* page is already allocated, just return */
130 /* this page has not been allocated yet */
132 spin_unlock_irq(&bitmap->lock);
133 mappage = bitmap_alloc_page(bitmap);
134 spin_lock_irq(&bitmap->lock);
136 if (mappage == NULL) {
137 PRINTK("%s: bitmap map page allocation failed, hijacking\n",
139 /* failed - set the hijacked flag so that we can use the
140 * pointer as a counter */
141 if (!bitmap->bp[page].map)
142 bitmap->bp[page].hijacked = 1;
143 } else if (bitmap->bp[page].map ||
144 bitmap->bp[page].hijacked) {
145 /* somebody beat us to getting the page */
146 bitmap_free_page(bitmap, mappage);
150 /* no page was in place and we have one, so install it */
152 bitmap->bp[page].map = mappage;
153 bitmap->missing_pages--;
158 /* if page is completely empty, put it back on the free list, or dealloc it */
159 /* if page was hijacked, unmark the flag so it might get alloced next time */
160 /* Note: lock should be held when calling this */
161 static void bitmap_checkfree(struct bitmap *bitmap, unsigned long page)
165 if (bitmap->bp[page].count) /* page is still busy */
168 /* page is no longer in use, it can be released */
170 if (bitmap->bp[page].hijacked) { /* page was hijacked, undo this now */
171 bitmap->bp[page].hijacked = 0;
172 bitmap->bp[page].map = NULL;
174 /* normal case, free the page */
175 ptr = bitmap->bp[page].map;
176 bitmap->bp[page].map = NULL;
177 bitmap->missing_pages++;
178 bitmap_free_page(bitmap, ptr);
183 * bitmap file handling - read and write the bitmap file and its superblock
187 * basic page I/O operations
190 /* IO operations when bitmap is stored near all superblocks */
191 static struct page *read_sb_page(mddev_t *mddev, loff_t offset,
193 unsigned long index, int size)
195 /* choose a good rdev and read the page from there */
202 page = alloc_page(GFP_KERNEL);
204 return ERR_PTR(-ENOMEM);
208 list_for_each_entry(rdev, &mddev->disks, same_set) {
209 if (! test_bit(In_sync, &rdev->flags)
210 || test_bit(Faulty, &rdev->flags))
213 target = offset + index * (PAGE_SIZE/512);
215 if (sync_page_io(rdev, target,
216 roundup(size, bdev_logical_block_size(rdev->bdev)),
219 attach_page_buffers(page, NULL); /* so that free_buffer will
226 return ERR_PTR(-EIO);
230 static mdk_rdev_t *next_active_rdev(mdk_rdev_t *rdev, mddev_t *mddev)
232 /* Iterate the disks of an mddev, using rcu to protect access to the
233 * linked list, and raising the refcount of devices we return to ensure
234 * they don't disappear while in use.
235 * As devices are only added or removed when raid_disk is < 0 and
236 * nr_pending is 0 and In_sync is clear, the entries we return will
237 * still be in the same position on the list when we re-enter
238 * list_for_each_continue_rcu.
240 struct list_head *pos;
243 /* start at the beginning */
246 /* release the previous rdev and start from there. */
247 rdev_dec_pending(rdev, mddev);
248 pos = &rdev->same_set;
250 list_for_each_continue_rcu(pos, &mddev->disks) {
251 rdev = list_entry(pos, mdk_rdev_t, same_set);
252 if (rdev->raid_disk >= 0 &&
253 !test_bit(Faulty, &rdev->flags)) {
254 /* this is a usable devices */
255 atomic_inc(&rdev->nr_pending);
264 static int write_sb_page(struct bitmap *bitmap, struct page *page, int wait)
266 mdk_rdev_t *rdev = NULL;
267 struct block_device *bdev;
268 mddev_t *mddev = bitmap->mddev;
270 while ((rdev = next_active_rdev(rdev, mddev)) != NULL) {
271 int size = PAGE_SIZE;
272 loff_t offset = mddev->bitmap_info.offset;
274 bdev = (rdev->meta_bdev) ? rdev->meta_bdev : rdev->bdev;
276 if (page->index == bitmap->file_pages-1)
277 size = roundup(bitmap->last_page_size,
278 bdev_logical_block_size(bdev));
279 /* Just make sure we aren't corrupting data or
282 if (mddev->external) {
283 /* Bitmap could be anywhere. */
284 if (rdev->sb_start + offset + (page->index
288 rdev->sb_start + offset
289 < (rdev->data_offset + mddev->dev_sectors
292 } else if (offset < 0) {
293 /* DATA BITMAP METADATA */
295 + (long)(page->index * (PAGE_SIZE/512))
297 /* bitmap runs in to metadata */
299 if (rdev->data_offset + mddev->dev_sectors
300 > rdev->sb_start + offset)
301 /* data runs in to bitmap */
303 } else if (rdev->sb_start < rdev->data_offset) {
304 /* METADATA BITMAP DATA */
307 + page->index*(PAGE_SIZE/512) + size/512
309 /* bitmap runs in to data */
312 /* DATA METADATA BITMAP - no problems */
314 md_super_write(mddev, rdev,
315 rdev->sb_start + offset
316 + page->index * (PAGE_SIZE/512),
322 md_super_wait(mddev);
329 static void bitmap_file_kick(struct bitmap *bitmap);
331 * write out a page to a file
333 static void write_page(struct bitmap *bitmap, struct page *page, int wait)
335 struct buffer_head *bh;
337 if (bitmap->file == NULL) {
338 switch (write_sb_page(bitmap, page, wait)) {
340 bitmap->flags |= BITMAP_WRITE_ERROR;
344 bh = page_buffers(page);
346 while (bh && bh->b_blocknr) {
347 atomic_inc(&bitmap->pending_writes);
348 set_buffer_locked(bh);
349 set_buffer_mapped(bh);
350 submit_bh(WRITE | REQ_SYNC, bh);
351 bh = bh->b_this_page;
355 wait_event(bitmap->write_wait,
356 atomic_read(&bitmap->pending_writes)==0);
358 if (bitmap->flags & BITMAP_WRITE_ERROR)
359 bitmap_file_kick(bitmap);
362 static void end_bitmap_write(struct buffer_head *bh, int uptodate)
364 struct bitmap *bitmap = bh->b_private;
368 spin_lock_irqsave(&bitmap->lock, flags);
369 bitmap->flags |= BITMAP_WRITE_ERROR;
370 spin_unlock_irqrestore(&bitmap->lock, flags);
372 if (atomic_dec_and_test(&bitmap->pending_writes))
373 wake_up(&bitmap->write_wait);
376 /* copied from buffer.c */
378 __clear_page_buffers(struct page *page)
380 ClearPagePrivate(page);
381 set_page_private(page, 0);
382 page_cache_release(page);
384 static void free_buffers(struct page *page)
386 struct buffer_head *bh = page_buffers(page);
389 struct buffer_head *next = bh->b_this_page;
390 free_buffer_head(bh);
393 __clear_page_buffers(page);
397 /* read a page from a file.
398 * We both read the page, and attach buffers to the page to record the
399 * address of each block (using bmap). These addresses will be used
400 * to write the block later, completely bypassing the filesystem.
401 * This usage is similar to how swap files are handled, and allows us
402 * to write to a file with no concerns of memory allocation failing.
404 static struct page *read_page(struct file *file, unsigned long index,
405 struct bitmap *bitmap,
408 struct page *page = NULL;
409 struct inode *inode = file->f_path.dentry->d_inode;
410 struct buffer_head *bh;
413 PRINTK("read bitmap file (%dB @ %llu)\n", (int)PAGE_SIZE,
414 (unsigned long long)index << PAGE_SHIFT);
416 page = alloc_page(GFP_KERNEL);
418 page = ERR_PTR(-ENOMEM);
422 bh = alloc_page_buffers(page, 1<<inode->i_blkbits, 0);
425 page = ERR_PTR(-ENOMEM);
428 attach_page_buffers(page, bh);
429 block = index << (PAGE_SHIFT - inode->i_blkbits);
434 bh->b_blocknr = bmap(inode, block);
435 if (bh->b_blocknr == 0) {
436 /* Cannot use this file! */
438 page = ERR_PTR(-EINVAL);
441 bh->b_bdev = inode->i_sb->s_bdev;
442 if (count < (1<<inode->i_blkbits))
445 count -= (1<<inode->i_blkbits);
447 bh->b_end_io = end_bitmap_write;
448 bh->b_private = bitmap;
449 atomic_inc(&bitmap->pending_writes);
450 set_buffer_locked(bh);
451 set_buffer_mapped(bh);
455 bh = bh->b_this_page;
459 wait_event(bitmap->write_wait,
460 atomic_read(&bitmap->pending_writes)==0);
461 if (bitmap->flags & BITMAP_WRITE_ERROR) {
463 page = ERR_PTR(-EIO);
467 printk(KERN_ALERT "md: bitmap read error: (%dB @ %llu): %ld\n",
469 (unsigned long long)index << PAGE_SHIFT,
475 * bitmap file superblock operations
478 /* update the event counter and sync the superblock to disk */
479 void bitmap_update_sb(struct bitmap *bitmap)
484 if (!bitmap || !bitmap->mddev) /* no bitmap for this array */
486 if (bitmap->mddev->bitmap_info.external)
488 spin_lock_irqsave(&bitmap->lock, flags);
489 if (!bitmap->sb_page) { /* no superblock */
490 spin_unlock_irqrestore(&bitmap->lock, flags);
493 spin_unlock_irqrestore(&bitmap->lock, flags);
494 sb = kmap_atomic(bitmap->sb_page, KM_USER0);
495 sb->events = cpu_to_le64(bitmap->mddev->events);
496 if (bitmap->mddev->events < bitmap->events_cleared)
497 /* rocking back to read-only */
498 bitmap->events_cleared = bitmap->mddev->events;
499 sb->events_cleared = cpu_to_le64(bitmap->events_cleared);
500 sb->state = cpu_to_le32(bitmap->flags);
501 /* Just in case these have been changed via sysfs: */
502 sb->daemon_sleep = cpu_to_le32(bitmap->mddev->bitmap_info.daemon_sleep/HZ);
503 sb->write_behind = cpu_to_le32(bitmap->mddev->bitmap_info.max_write_behind);
504 kunmap_atomic(sb, KM_USER0);
505 write_page(bitmap, bitmap->sb_page, 1);
508 /* print out the bitmap file superblock */
509 void bitmap_print_sb(struct bitmap *bitmap)
513 if (!bitmap || !bitmap->sb_page)
515 sb = kmap_atomic(bitmap->sb_page, KM_USER0);
516 printk(KERN_DEBUG "%s: bitmap file superblock:\n", bmname(bitmap));
517 printk(KERN_DEBUG " magic: %08x\n", le32_to_cpu(sb->magic));
518 printk(KERN_DEBUG " version: %d\n", le32_to_cpu(sb->version));
519 printk(KERN_DEBUG " uuid: %08x.%08x.%08x.%08x\n",
520 *(__u32 *)(sb->uuid+0),
521 *(__u32 *)(sb->uuid+4),
522 *(__u32 *)(sb->uuid+8),
523 *(__u32 *)(sb->uuid+12));
524 printk(KERN_DEBUG " events: %llu\n",
525 (unsigned long long) le64_to_cpu(sb->events));
526 printk(KERN_DEBUG "events cleared: %llu\n",
527 (unsigned long long) le64_to_cpu(sb->events_cleared));
528 printk(KERN_DEBUG " state: %08x\n", le32_to_cpu(sb->state));
529 printk(KERN_DEBUG " chunksize: %d B\n", le32_to_cpu(sb->chunksize));
530 printk(KERN_DEBUG " daemon sleep: %ds\n", le32_to_cpu(sb->daemon_sleep));
531 printk(KERN_DEBUG " sync size: %llu KB\n",
532 (unsigned long long)le64_to_cpu(sb->sync_size)/2);
533 printk(KERN_DEBUG "max write behind: %d\n", le32_to_cpu(sb->write_behind));
534 kunmap_atomic(sb, KM_USER0);
541 * This function is somewhat the reverse of bitmap_read_sb. bitmap_read_sb
542 * reads and verifies the on-disk bitmap superblock and populates bitmap_info.
543 * This function verifies 'bitmap_info' and populates the on-disk bitmap
544 * structure, which is to be written to disk.
546 * Returns: 0 on success, -Exxx on error
548 static int bitmap_new_disk_sb(struct bitmap *bitmap)
551 unsigned long chunksize, daemon_sleep, write_behind;
554 bitmap->sb_page = alloc_page(GFP_KERNEL);
555 if (IS_ERR(bitmap->sb_page)) {
556 err = PTR_ERR(bitmap->sb_page);
557 bitmap->sb_page = NULL;
560 bitmap->sb_page->index = 0;
562 sb = kmap_atomic(bitmap->sb_page, KM_USER0);
564 sb->magic = cpu_to_le32(BITMAP_MAGIC);
565 sb->version = cpu_to_le32(BITMAP_MAJOR_HI);
567 chunksize = bitmap->mddev->bitmap_info.chunksize;
569 if (!is_power_of_2(chunksize)) {
570 kunmap_atomic(sb, KM_USER0);
571 printk(KERN_ERR "bitmap chunksize not a power of 2\n");
574 sb->chunksize = cpu_to_le32(chunksize);
576 daemon_sleep = bitmap->mddev->bitmap_info.daemon_sleep;
578 (daemon_sleep < 1) || (daemon_sleep > MAX_SCHEDULE_TIMEOUT)) {
579 printk(KERN_INFO "Choosing daemon_sleep default (5 sec)\n");
580 daemon_sleep = 5 * HZ;
582 sb->daemon_sleep = cpu_to_le32(daemon_sleep);
583 bitmap->mddev->bitmap_info.daemon_sleep = daemon_sleep;
586 * FIXME: write_behind for RAID1. If not specified, what
587 * is a good choice? We choose COUNTER_MAX / 2 arbitrarily.
589 write_behind = bitmap->mddev->bitmap_info.max_write_behind;
590 if (write_behind > COUNTER_MAX)
591 write_behind = COUNTER_MAX / 2;
592 sb->write_behind = cpu_to_le32(write_behind);
593 bitmap->mddev->bitmap_info.max_write_behind = write_behind;
595 /* keep the array size field of the bitmap superblock up to date */
596 sb->sync_size = cpu_to_le64(bitmap->mddev->resync_max_sectors);
598 memcpy(sb->uuid, bitmap->mddev->uuid, 16);
600 bitmap->flags |= BITMAP_STALE;
601 sb->state |= cpu_to_le32(BITMAP_STALE);
602 bitmap->events_cleared = bitmap->mddev->events;
603 sb->events_cleared = cpu_to_le64(bitmap->mddev->events);
605 bitmap->flags |= BITMAP_HOSTENDIAN;
606 sb->version = cpu_to_le32(BITMAP_MAJOR_HOSTENDIAN);
608 kunmap_atomic(sb, KM_USER0);
613 /* read the superblock from the bitmap file and initialize some bitmap fields */
614 static int bitmap_read_sb(struct bitmap *bitmap)
618 unsigned long chunksize, daemon_sleep, write_behind;
619 unsigned long long events;
622 /* page 0 is the superblock, read it... */
624 loff_t isize = i_size_read(bitmap->file->f_mapping->host);
625 int bytes = isize > PAGE_SIZE ? PAGE_SIZE : isize;
627 bitmap->sb_page = read_page(bitmap->file, 0, bitmap, bytes);
629 bitmap->sb_page = read_sb_page(bitmap->mddev,
630 bitmap->mddev->bitmap_info.offset,
632 0, sizeof(bitmap_super_t));
634 if (IS_ERR(bitmap->sb_page)) {
635 err = PTR_ERR(bitmap->sb_page);
636 bitmap->sb_page = NULL;
640 sb = kmap_atomic(bitmap->sb_page, KM_USER0);
642 chunksize = le32_to_cpu(sb->chunksize);
643 daemon_sleep = le32_to_cpu(sb->daemon_sleep) * HZ;
644 write_behind = le32_to_cpu(sb->write_behind);
646 /* verify that the bitmap-specific fields are valid */
647 if (sb->magic != cpu_to_le32(BITMAP_MAGIC))
648 reason = "bad magic";
649 else if (le32_to_cpu(sb->version) < BITMAP_MAJOR_LO ||
650 le32_to_cpu(sb->version) > BITMAP_MAJOR_HI)
651 reason = "unrecognized superblock version";
652 else if (chunksize < 512)
653 reason = "bitmap chunksize too small";
654 else if (!is_power_of_2(chunksize))
655 reason = "bitmap chunksize not a power of 2";
656 else if (daemon_sleep < 1 || daemon_sleep > MAX_SCHEDULE_TIMEOUT)
657 reason = "daemon sleep period out of range";
658 else if (write_behind > COUNTER_MAX)
659 reason = "write-behind limit out of range (0 - 16383)";
661 printk(KERN_INFO "%s: invalid bitmap file superblock: %s\n",
662 bmname(bitmap), reason);
666 /* keep the array size field of the bitmap superblock up to date */
667 sb->sync_size = cpu_to_le64(bitmap->mddev->resync_max_sectors);
669 if (!bitmap->mddev->persistent)
673 * if we have a persistent array superblock, compare the
674 * bitmap's UUID and event counter to the mddev's
676 if (memcmp(sb->uuid, bitmap->mddev->uuid, 16)) {
677 printk(KERN_INFO "%s: bitmap superblock UUID mismatch\n",
681 events = le64_to_cpu(sb->events);
682 if (events < bitmap->mddev->events) {
683 printk(KERN_INFO "%s: bitmap file is out of date (%llu < %llu) "
684 "-- forcing full recovery\n", bmname(bitmap), events,
685 (unsigned long long) bitmap->mddev->events);
686 sb->state |= cpu_to_le32(BITMAP_STALE);
689 /* assign fields using values from superblock */
690 bitmap->mddev->bitmap_info.chunksize = chunksize;
691 bitmap->mddev->bitmap_info.daemon_sleep = daemon_sleep;
692 bitmap->mddev->bitmap_info.max_write_behind = write_behind;
693 bitmap->flags |= le32_to_cpu(sb->state);
694 if (le32_to_cpu(sb->version) == BITMAP_MAJOR_HOSTENDIAN)
695 bitmap->flags |= BITMAP_HOSTENDIAN;
696 bitmap->events_cleared = le64_to_cpu(sb->events_cleared);
697 if (bitmap->flags & BITMAP_STALE)
698 bitmap->events_cleared = bitmap->mddev->events;
701 kunmap_atomic(sb, KM_USER0);
703 bitmap_print_sb(bitmap);
707 enum bitmap_mask_op {
712 /* record the state of the bitmap in the superblock. Return the old value */
713 static int bitmap_mask_state(struct bitmap *bitmap, enum bitmap_state bits,
714 enum bitmap_mask_op op)
720 spin_lock_irqsave(&bitmap->lock, flags);
721 if (!bitmap->sb_page) { /* can't set the state */
722 spin_unlock_irqrestore(&bitmap->lock, flags);
725 spin_unlock_irqrestore(&bitmap->lock, flags);
726 sb = kmap_atomic(bitmap->sb_page, KM_USER0);
727 old = le32_to_cpu(sb->state) & bits;
730 sb->state |= cpu_to_le32(bits);
731 bitmap->flags |= bits;
734 sb->state &= cpu_to_le32(~bits);
735 bitmap->flags &= ~bits;
740 kunmap_atomic(sb, KM_USER0);
745 * general bitmap file operations
751 * Use one bit per "chunk" (block set). We do the disk I/O on the bitmap
752 * file a page at a time. There's a superblock at the start of the file.
754 /* calculate the index of the page that contains this bit */
755 static inline unsigned long file_page_index(struct bitmap *bitmap, unsigned long chunk)
757 if (!bitmap->mddev->bitmap_info.external)
758 chunk += sizeof(bitmap_super_t) << 3;
759 return chunk >> PAGE_BIT_SHIFT;
762 /* calculate the (bit) offset of this bit within a page */
763 static inline unsigned long file_page_offset(struct bitmap *bitmap, unsigned long chunk)
765 if (!bitmap->mddev->bitmap_info.external)
766 chunk += sizeof(bitmap_super_t) << 3;
767 return chunk & (PAGE_BITS - 1);
771 * return a pointer to the page in the filemap that contains the given bit
773 * this lookup is complicated by the fact that the bitmap sb might be exactly
774 * 1 page (e.g., x86) or less than 1 page -- so the bitmap might start on page
777 static inline struct page *filemap_get_page(struct bitmap *bitmap,
780 if (bitmap->filemap == NULL)
782 if (file_page_index(bitmap, chunk) >= bitmap->file_pages)
784 return bitmap->filemap[file_page_index(bitmap, chunk)
785 - file_page_index(bitmap, 0)];
788 static void bitmap_file_unmap(struct bitmap *bitmap)
790 struct page **map, *sb_page;
795 spin_lock_irqsave(&bitmap->lock, flags);
796 map = bitmap->filemap;
797 bitmap->filemap = NULL;
798 attr = bitmap->filemap_attr;
799 bitmap->filemap_attr = NULL;
800 pages = bitmap->file_pages;
801 bitmap->file_pages = 0;
802 sb_page = bitmap->sb_page;
803 bitmap->sb_page = NULL;
804 spin_unlock_irqrestore(&bitmap->lock, flags);
807 if (map[pages] != sb_page) /* 0 is sb_page, release it below */
808 free_buffers(map[pages]);
813 free_buffers(sb_page);
816 static void bitmap_file_put(struct bitmap *bitmap)
821 spin_lock_irqsave(&bitmap->lock, flags);
824 spin_unlock_irqrestore(&bitmap->lock, flags);
827 wait_event(bitmap->write_wait,
828 atomic_read(&bitmap->pending_writes)==0);
829 bitmap_file_unmap(bitmap);
832 struct inode *inode = file->f_path.dentry->d_inode;
833 invalidate_mapping_pages(inode->i_mapping, 0, -1);
839 * bitmap_file_kick - if an error occurs while manipulating the bitmap file
840 * then it is no longer reliable, so we stop using it and we mark the file
841 * as failed in the superblock
843 static void bitmap_file_kick(struct bitmap *bitmap)
845 char *path, *ptr = NULL;
847 if (bitmap_mask_state(bitmap, BITMAP_STALE, MASK_SET) == 0) {
848 bitmap_update_sb(bitmap);
851 path = kmalloc(PAGE_SIZE, GFP_KERNEL);
853 ptr = d_path(&bitmap->file->f_path, path,
857 "%s: kicking failed bitmap file %s from array!\n",
858 bmname(bitmap), IS_ERR(ptr) ? "" : ptr);
863 "%s: disabling internal bitmap due to errors\n",
867 bitmap_file_put(bitmap);
872 enum bitmap_page_attr {
873 BITMAP_PAGE_DIRTY = 0, /* there are set bits that need to be synced */
874 BITMAP_PAGE_CLEAN = 1, /* there are bits that might need to be cleared */
875 BITMAP_PAGE_NEEDWRITE = 2, /* there are cleared bits that need to be synced */
878 static inline void set_page_attr(struct bitmap *bitmap, struct page *page,
879 enum bitmap_page_attr attr)
882 __set_bit((page->index<<2) + attr, bitmap->filemap_attr);
884 __set_bit(attr, &bitmap->logattrs);
887 static inline void clear_page_attr(struct bitmap *bitmap, struct page *page,
888 enum bitmap_page_attr attr)
891 __clear_bit((page->index<<2) + attr, bitmap->filemap_attr);
893 __clear_bit(attr, &bitmap->logattrs);
896 static inline unsigned long test_page_attr(struct bitmap *bitmap, struct page *page,
897 enum bitmap_page_attr attr)
900 return test_bit((page->index<<2) + attr, bitmap->filemap_attr);
902 return test_bit(attr, &bitmap->logattrs);
906 * bitmap_file_set_bit -- called before performing a write to the md device
907 * to set (and eventually sync) a particular bit in the bitmap file
909 * we set the bit immediately, then we record the page number so that
910 * when an unplug occurs, we can flush the dirty pages out to disk
912 static void bitmap_file_set_bit(struct bitmap *bitmap, sector_t block)
915 struct page *page = NULL;
917 unsigned long chunk = block >> CHUNK_BLOCK_SHIFT(bitmap);
919 if (!bitmap->filemap) {
920 struct dm_dirty_log *log = bitmap->mddev->bitmap_info.log;
922 log->type->mark_region(log, chunk);
925 page = filemap_get_page(bitmap, chunk);
928 bit = file_page_offset(bitmap, chunk);
931 kaddr = kmap_atomic(page, KM_USER0);
932 if (bitmap->flags & BITMAP_HOSTENDIAN)
935 __test_and_set_bit_le(bit, kaddr);
936 kunmap_atomic(kaddr, KM_USER0);
937 PRINTK("set file bit %lu page %lu\n", bit, page->index);
939 /* record page number so it gets flushed to disk when unplug occurs */
940 set_page_attr(bitmap, page, BITMAP_PAGE_DIRTY);
943 /* this gets called when the md device is ready to unplug its underlying
944 * (slave) device queues -- before we let any writes go down, we need to
945 * sync the dirty pages of the bitmap file to disk */
946 void bitmap_unplug(struct bitmap *bitmap)
948 unsigned long i, flags;
949 int dirty, need_write;
955 if (!bitmap->filemap) {
956 /* Must be using a dirty_log */
957 struct dm_dirty_log *log = bitmap->mddev->bitmap_info.log;
958 dirty = test_and_clear_bit(BITMAP_PAGE_DIRTY, &bitmap->logattrs);
959 need_write = test_and_clear_bit(BITMAP_PAGE_NEEDWRITE, &bitmap->logattrs);
960 if (dirty || need_write)
961 if (log->type->flush(log))
962 bitmap->flags |= BITMAP_WRITE_ERROR;
966 /* look at each page to see if there are any set bits that need to be
967 * flushed out to disk */
968 for (i = 0; i < bitmap->file_pages; i++) {
969 spin_lock_irqsave(&bitmap->lock, flags);
970 if (!bitmap->filemap) {
971 spin_unlock_irqrestore(&bitmap->lock, flags);
974 page = bitmap->filemap[i];
975 dirty = test_page_attr(bitmap, page, BITMAP_PAGE_DIRTY);
976 need_write = test_page_attr(bitmap, page, BITMAP_PAGE_NEEDWRITE);
977 clear_page_attr(bitmap, page, BITMAP_PAGE_DIRTY);
978 clear_page_attr(bitmap, page, BITMAP_PAGE_NEEDWRITE);
981 spin_unlock_irqrestore(&bitmap->lock, flags);
983 if (dirty || need_write)
984 write_page(bitmap, page, 0);
986 if (wait) { /* if any writes were performed, we need to wait on them */
988 wait_event(bitmap->write_wait,
989 atomic_read(&bitmap->pending_writes)==0);
991 md_super_wait(bitmap->mddev);
994 if (bitmap->flags & BITMAP_WRITE_ERROR)
995 bitmap_file_kick(bitmap);
997 EXPORT_SYMBOL(bitmap_unplug);
999 static void bitmap_set_memory_bits(struct bitmap *bitmap, sector_t offset, int needed);
1000 /* * bitmap_init_from_disk -- called at bitmap_create time to initialize
1001 * the in-memory bitmap from the on-disk bitmap -- also, sets up the
1002 * memory mapping of the bitmap file
1004 * if there's no bitmap file, or if the bitmap file had been
1005 * previously kicked from the array, we mark all the bits as
1006 * 1's in order to cause a full resync.
1008 * We ignore all bits for sectors that end earlier than 'start'.
1009 * This is used when reading an out-of-date bitmap...
1011 static int bitmap_init_from_disk(struct bitmap *bitmap, sector_t start)
1013 unsigned long i, chunks, index, oldindex, bit;
1014 struct page *page = NULL, *oldpage = NULL;
1015 unsigned long num_pages, bit_cnt = 0;
1017 unsigned long bytes, offset;
1022 chunks = bitmap->chunks;
1023 file = bitmap->file;
1025 BUG_ON(!file && !bitmap->mddev->bitmap_info.offset);
1027 #ifdef INJECT_FAULTS_3
1030 outofdate = bitmap->flags & BITMAP_STALE;
1033 printk(KERN_INFO "%s: bitmap file is out of date, doing full "
1034 "recovery\n", bmname(bitmap));
1036 bytes = DIV_ROUND_UP(bitmap->chunks, 8);
1037 if (!bitmap->mddev->bitmap_info.external)
1038 bytes += sizeof(bitmap_super_t);
1040 num_pages = DIV_ROUND_UP(bytes, PAGE_SIZE);
1042 if (file && i_size_read(file->f_mapping->host) < bytes) {
1043 printk(KERN_INFO "%s: bitmap file too short %lu < %lu\n",
1045 (unsigned long) i_size_read(file->f_mapping->host),
1052 bitmap->filemap = kmalloc(sizeof(struct page *) * num_pages, GFP_KERNEL);
1053 if (!bitmap->filemap)
1056 /* We need 4 bits per page, rounded up to a multiple of sizeof(unsigned long) */
1057 bitmap->filemap_attr = kzalloc(
1058 roundup(DIV_ROUND_UP(num_pages*4, 8), sizeof(unsigned long)),
1060 if (!bitmap->filemap_attr)
1065 for (i = 0; i < chunks; i++) {
1067 index = file_page_index(bitmap, i);
1068 bit = file_page_offset(bitmap, i);
1069 if (index != oldindex) { /* this is a new page, read it in */
1071 /* unmap the old page, we're done with it */
1072 if (index == num_pages-1)
1073 count = bytes - index * PAGE_SIZE;
1076 if (index == 0 && bitmap->sb_page) {
1078 * if we're here then the superblock page
1079 * contains some bits (PAGE_SIZE != sizeof sb)
1080 * we've already read it in, so just use it
1082 page = bitmap->sb_page;
1083 offset = sizeof(bitmap_super_t);
1085 page = read_sb_page(
1087 bitmap->mddev->bitmap_info.offset,
1091 page = read_page(file, index, bitmap, count);
1094 page = read_sb_page(bitmap->mddev,
1095 bitmap->mddev->bitmap_info.offset,
1100 if (IS_ERR(page)) { /* read error */
1101 ret = PTR_ERR(page);
1108 bitmap->filemap[bitmap->file_pages++] = page;
1109 bitmap->last_page_size = count;
1113 * if bitmap is out of date, dirty the
1114 * whole page and write it out
1116 paddr = kmap_atomic(page, KM_USER0);
1117 memset(paddr + offset, 0xff,
1118 PAGE_SIZE - offset);
1119 kunmap_atomic(paddr, KM_USER0);
1120 write_page(bitmap, page, 1);
1123 if (bitmap->flags & BITMAP_WRITE_ERROR)
1127 paddr = kmap_atomic(page, KM_USER0);
1128 if (bitmap->flags & BITMAP_HOSTENDIAN)
1129 b = test_bit(bit, paddr);
1131 b = test_bit_le(bit, paddr);
1132 kunmap_atomic(paddr, KM_USER0);
1134 /* if the disk bit is set, set the memory bit */
1135 int needed = ((sector_t)(i+1) << (CHUNK_BLOCK_SHIFT(bitmap))
1137 bitmap_set_memory_bits(bitmap,
1138 (sector_t)i << CHUNK_BLOCK_SHIFT(bitmap),
1141 set_page_attr(bitmap, page, BITMAP_PAGE_CLEAN);
1145 /* everything went OK */
1147 bitmap_mask_state(bitmap, BITMAP_STALE, MASK_UNSET);
1149 if (bit_cnt) { /* Kick recovery if any bits were set */
1150 set_bit(MD_RECOVERY_NEEDED, &bitmap->mddev->recovery);
1151 md_wakeup_thread(bitmap->mddev->thread);
1154 printk(KERN_INFO "%s: bitmap initialized from disk: "
1155 "read %lu/%lu pages, set %lu of %lu bits\n",
1156 bmname(bitmap), bitmap->file_pages, num_pages, bit_cnt, chunks);
1161 printk(KERN_INFO "%s: bitmap initialisation failed: %d\n",
1162 bmname(bitmap), ret);
1166 void bitmap_write_all(struct bitmap *bitmap)
1168 /* We don't actually write all bitmap blocks here,
1169 * just flag them as needing to be written
1173 for (i = 0; i < bitmap->file_pages; i++)
1174 set_page_attr(bitmap, bitmap->filemap[i],
1175 BITMAP_PAGE_NEEDWRITE);
1178 static void bitmap_count_page(struct bitmap *bitmap, sector_t offset, int inc)
1180 sector_t chunk = offset >> CHUNK_BLOCK_SHIFT(bitmap);
1181 unsigned long page = chunk >> PAGE_COUNTER_SHIFT;
1182 bitmap->bp[page].count += inc;
1183 bitmap_checkfree(bitmap, page);
1185 static bitmap_counter_t *bitmap_get_counter(struct bitmap *bitmap,
1186 sector_t offset, sector_t *blocks,
1190 * bitmap daemon -- periodically wakes up to clean bits and flush pages
1194 void bitmap_daemon_work(mddev_t *mddev)
1196 struct bitmap *bitmap;
1198 unsigned long flags;
1199 struct page *page = NULL, *lastpage = NULL;
1202 struct dm_dirty_log *log = mddev->bitmap_info.log;
1204 /* Use a mutex to guard daemon_work against
1207 mutex_lock(&mddev->bitmap_info.mutex);
1208 bitmap = mddev->bitmap;
1209 if (bitmap == NULL) {
1210 mutex_unlock(&mddev->bitmap_info.mutex);
1213 if (time_before(jiffies, bitmap->daemon_lastrun
1214 + bitmap->mddev->bitmap_info.daemon_sleep))
1217 bitmap->daemon_lastrun = jiffies;
1218 if (bitmap->allclean) {
1219 bitmap->mddev->thread->timeout = MAX_SCHEDULE_TIMEOUT;
1222 bitmap->allclean = 1;
1224 spin_lock_irqsave(&bitmap->lock, flags);
1225 for (j = 0; j < bitmap->chunks; j++) {
1226 bitmap_counter_t *bmc;
1227 if (!bitmap->filemap) {
1229 /* error or shutdown */
1232 page = filemap_get_page(bitmap, j);
1234 if (page != lastpage) {
1235 /* skip this page unless it's marked as needing cleaning */
1236 if (!test_page_attr(bitmap, page, BITMAP_PAGE_CLEAN)) {
1237 int need_write = test_page_attr(bitmap, page,
1238 BITMAP_PAGE_NEEDWRITE);
1240 clear_page_attr(bitmap, page, BITMAP_PAGE_NEEDWRITE);
1242 spin_unlock_irqrestore(&bitmap->lock, flags);
1244 write_page(bitmap, page, 0);
1245 bitmap->allclean = 0;
1247 spin_lock_irqsave(&bitmap->lock, flags);
1248 j |= (PAGE_BITS - 1);
1252 /* grab the new page, sync and release the old */
1253 if (lastpage != NULL) {
1254 if (test_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE)) {
1255 clear_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE);
1256 spin_unlock_irqrestore(&bitmap->lock, flags);
1257 write_page(bitmap, lastpage, 0);
1259 set_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE);
1260 spin_unlock_irqrestore(&bitmap->lock, flags);
1263 spin_unlock_irqrestore(&bitmap->lock, flags);
1266 /* We are possibly going to clear some bits, so make
1267 * sure that events_cleared is up-to-date.
1269 if (bitmap->need_sync &&
1270 bitmap->mddev->bitmap_info.external == 0) {
1272 bitmap->need_sync = 0;
1273 sb = kmap_atomic(bitmap->sb_page, KM_USER0);
1274 sb->events_cleared =
1275 cpu_to_le64(bitmap->events_cleared);
1276 kunmap_atomic(sb, KM_USER0);
1277 write_page(bitmap, bitmap->sb_page, 1);
1279 spin_lock_irqsave(&bitmap->lock, flags);
1280 if (!bitmap->need_sync)
1281 clear_page_attr(bitmap, page, BITMAP_PAGE_CLEAN);
1283 bmc = bitmap_get_counter(bitmap,
1284 (sector_t)j << CHUNK_BLOCK_SHIFT(bitmap),
1288 bitmap->allclean = 0;
1291 *bmc = 1; /* maybe clear the bit next time */
1292 set_page_attr(bitmap, page, BITMAP_PAGE_CLEAN);
1293 } else if (*bmc == 1 && !bitmap->need_sync) {
1294 /* we can clear the bit */
1296 bitmap_count_page(bitmap,
1297 (sector_t)j << CHUNK_BLOCK_SHIFT(bitmap),
1302 paddr = kmap_atomic(page, KM_USER0);
1303 if (bitmap->flags & BITMAP_HOSTENDIAN)
1304 clear_bit(file_page_offset(bitmap, j),
1307 __test_and_clear_bit_le(file_page_offset(bitmap, j),
1309 kunmap_atomic(paddr, KM_USER0);
1311 log->type->clear_region(log, j);
1314 j |= PAGE_COUNTER_MASK;
1316 spin_unlock_irqrestore(&bitmap->lock, flags);
1318 /* now sync the final page */
1319 if (lastpage != NULL || log != NULL) {
1320 spin_lock_irqsave(&bitmap->lock, flags);
1321 if (test_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE)) {
1322 clear_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE);
1323 spin_unlock_irqrestore(&bitmap->lock, flags);
1325 write_page(bitmap, lastpage, 0);
1327 if (log->type->flush(log))
1328 bitmap->flags |= BITMAP_WRITE_ERROR;
1330 set_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE);
1331 spin_unlock_irqrestore(&bitmap->lock, flags);
1336 if (bitmap->allclean == 0)
1337 bitmap->mddev->thread->timeout =
1338 bitmap->mddev->bitmap_info.daemon_sleep;
1339 mutex_unlock(&mddev->bitmap_info.mutex);
1342 static bitmap_counter_t *bitmap_get_counter(struct bitmap *bitmap,
1343 sector_t offset, sector_t *blocks,
1345 __releases(bitmap->lock)
1346 __acquires(bitmap->lock)
1348 /* If 'create', we might release the lock and reclaim it.
1349 * The lock must have been taken with interrupts enabled.
1350 * If !create, we don't release the lock.
1352 sector_t chunk = offset >> CHUNK_BLOCK_SHIFT(bitmap);
1353 unsigned long page = chunk >> PAGE_COUNTER_SHIFT;
1354 unsigned long pageoff = (chunk & PAGE_COUNTER_MASK) << COUNTER_BYTE_SHIFT;
1358 err = bitmap_checkpage(bitmap, page, create);
1360 if (bitmap->bp[page].hijacked ||
1361 bitmap->bp[page].map == NULL)
1362 csize = ((sector_t)1) << (CHUNK_BLOCK_SHIFT(bitmap) +
1363 PAGE_COUNTER_SHIFT - 1);
1365 csize = ((sector_t)1) << (CHUNK_BLOCK_SHIFT(bitmap));
1366 *blocks = csize - (offset & (csize - 1));
1371 /* now locked ... */
1373 if (bitmap->bp[page].hijacked) { /* hijacked pointer */
1374 /* should we use the first or second counter field
1375 * of the hijacked pointer? */
1376 int hi = (pageoff > PAGE_COUNTER_MASK);
1377 return &((bitmap_counter_t *)
1378 &bitmap->bp[page].map)[hi];
1379 } else /* page is allocated */
1380 return (bitmap_counter_t *)
1381 &(bitmap->bp[page].map[pageoff]);
1384 int bitmap_startwrite(struct bitmap *bitmap, sector_t offset, unsigned long sectors, int behind)
1391 atomic_inc(&bitmap->behind_writes);
1392 bw = atomic_read(&bitmap->behind_writes);
1393 if (bw > bitmap->behind_writes_used)
1394 bitmap->behind_writes_used = bw;
1396 PRINTK(KERN_DEBUG "inc write-behind count %d/%d\n",
1397 bw, bitmap->max_write_behind);
1402 bitmap_counter_t *bmc;
1404 spin_lock_irq(&bitmap->lock);
1405 bmc = bitmap_get_counter(bitmap, offset, &blocks, 1);
1407 spin_unlock_irq(&bitmap->lock);
1411 if (unlikely(COUNTER(*bmc) == COUNTER_MAX)) {
1412 DEFINE_WAIT(__wait);
1413 /* note that it is safe to do the prepare_to_wait
1414 * after the test as long as we do it before dropping
1417 prepare_to_wait(&bitmap->overflow_wait, &__wait,
1418 TASK_UNINTERRUPTIBLE);
1419 spin_unlock_irq(&bitmap->lock);
1421 finish_wait(&bitmap->overflow_wait, &__wait);
1427 bitmap_file_set_bit(bitmap, offset);
1428 bitmap_count_page(bitmap, offset, 1);
1436 spin_unlock_irq(&bitmap->lock);
1439 if (sectors > blocks)
1444 bitmap->allclean = 0;
1447 EXPORT_SYMBOL(bitmap_startwrite);
1449 void bitmap_endwrite(struct bitmap *bitmap, sector_t offset, unsigned long sectors,
1450 int success, int behind)
1455 if (atomic_dec_and_test(&bitmap->behind_writes))
1456 wake_up(&bitmap->behind_wait);
1457 PRINTK(KERN_DEBUG "dec write-behind count %d/%d\n",
1458 atomic_read(&bitmap->behind_writes), bitmap->max_write_behind);
1460 if (bitmap->mddev->degraded)
1461 /* Never clear bits or update events_cleared when degraded */
1466 unsigned long flags;
1467 bitmap_counter_t *bmc;
1469 spin_lock_irqsave(&bitmap->lock, flags);
1470 bmc = bitmap_get_counter(bitmap, offset, &blocks, 0);
1472 spin_unlock_irqrestore(&bitmap->lock, flags);
1477 bitmap->events_cleared < bitmap->mddev->events) {
1478 bitmap->events_cleared = bitmap->mddev->events;
1479 bitmap->need_sync = 1;
1480 sysfs_notify_dirent_safe(bitmap->sysfs_can_clear);
1483 if (!success && !NEEDED(*bmc))
1484 *bmc |= NEEDED_MASK;
1486 if (COUNTER(*bmc) == COUNTER_MAX)
1487 wake_up(&bitmap->overflow_wait);
1491 set_page_attr(bitmap,
1494 offset >> CHUNK_BLOCK_SHIFT(bitmap)),
1497 spin_unlock_irqrestore(&bitmap->lock, flags);
1499 if (sectors > blocks)
1505 EXPORT_SYMBOL(bitmap_endwrite);
1507 static int __bitmap_start_sync(struct bitmap *bitmap, sector_t offset, sector_t *blocks,
1510 bitmap_counter_t *bmc;
1512 if (bitmap == NULL) {/* FIXME or bitmap set as 'failed' */
1514 return 1; /* always resync if no bitmap */
1516 spin_lock_irq(&bitmap->lock);
1517 bmc = bitmap_get_counter(bitmap, offset, blocks, 0);
1523 else if (NEEDED(*bmc)) {
1525 if (!degraded) { /* don't set/clear bits if degraded */
1526 *bmc |= RESYNC_MASK;
1527 *bmc &= ~NEEDED_MASK;
1531 spin_unlock_irq(&bitmap->lock);
1532 bitmap->allclean = 0;
1536 int bitmap_start_sync(struct bitmap *bitmap, sector_t offset, sector_t *blocks,
1539 /* bitmap_start_sync must always report on multiples of whole
1540 * pages, otherwise resync (which is very PAGE_SIZE based) will
1542 * So call __bitmap_start_sync repeatedly (if needed) until
1543 * At least PAGE_SIZE>>9 blocks are covered.
1544 * Return the 'or' of the result.
1550 while (*blocks < (PAGE_SIZE>>9)) {
1551 rv |= __bitmap_start_sync(bitmap, offset,
1552 &blocks1, degraded);
1558 EXPORT_SYMBOL(bitmap_start_sync);
1560 void bitmap_end_sync(struct bitmap *bitmap, sector_t offset, sector_t *blocks, int aborted)
1562 bitmap_counter_t *bmc;
1563 unsigned long flags;
1565 if (bitmap == NULL) {
1569 spin_lock_irqsave(&bitmap->lock, flags);
1570 bmc = bitmap_get_counter(bitmap, offset, blocks, 0);
1575 *bmc &= ~RESYNC_MASK;
1577 if (!NEEDED(*bmc) && aborted)
1578 *bmc |= NEEDED_MASK;
1581 set_page_attr(bitmap,
1582 filemap_get_page(bitmap, offset >> CHUNK_BLOCK_SHIFT(bitmap)),
1587 spin_unlock_irqrestore(&bitmap->lock, flags);
1588 bitmap->allclean = 0;
1590 EXPORT_SYMBOL(bitmap_end_sync);
1592 void bitmap_close_sync(struct bitmap *bitmap)
1594 /* Sync has finished, and any bitmap chunks that weren't synced
1595 * properly have been aborted. It remains to us to clear the
1596 * RESYNC bit wherever it is still on
1598 sector_t sector = 0;
1602 while (sector < bitmap->mddev->resync_max_sectors) {
1603 bitmap_end_sync(bitmap, sector, &blocks, 0);
1607 EXPORT_SYMBOL(bitmap_close_sync);
1609 void bitmap_cond_end_sync(struct bitmap *bitmap, sector_t sector)
1617 bitmap->last_end_sync = jiffies;
1620 if (time_before(jiffies, (bitmap->last_end_sync
1621 + bitmap->mddev->bitmap_info.daemon_sleep)))
1623 wait_event(bitmap->mddev->recovery_wait,
1624 atomic_read(&bitmap->mddev->recovery_active) == 0);
1626 bitmap->mddev->curr_resync_completed = sector;
1627 set_bit(MD_CHANGE_CLEAN, &bitmap->mddev->flags);
1628 sector &= ~((1ULL << CHUNK_BLOCK_SHIFT(bitmap)) - 1);
1630 while (s < sector && s < bitmap->mddev->resync_max_sectors) {
1631 bitmap_end_sync(bitmap, s, &blocks, 0);
1634 bitmap->last_end_sync = jiffies;
1635 sysfs_notify(&bitmap->mddev->kobj, NULL, "sync_completed");
1637 EXPORT_SYMBOL(bitmap_cond_end_sync);
1639 static void bitmap_set_memory_bits(struct bitmap *bitmap, sector_t offset, int needed)
1641 /* For each chunk covered by any of these sectors, set the
1642 * counter to 1 and set resync_needed. They should all
1643 * be 0 at this point
1647 bitmap_counter_t *bmc;
1648 spin_lock_irq(&bitmap->lock);
1649 bmc = bitmap_get_counter(bitmap, offset, &secs, 1);
1651 spin_unlock_irq(&bitmap->lock);
1656 *bmc = 1 | (needed ? NEEDED_MASK : 0);
1657 bitmap_count_page(bitmap, offset, 1);
1658 page = filemap_get_page(bitmap, offset >> CHUNK_BLOCK_SHIFT(bitmap));
1659 set_page_attr(bitmap, page, BITMAP_PAGE_CLEAN);
1661 spin_unlock_irq(&bitmap->lock);
1662 bitmap->allclean = 0;
1665 /* dirty the memory and file bits for bitmap chunks "s" to "e" */
1666 void bitmap_dirty_bits(struct bitmap *bitmap, unsigned long s, unsigned long e)
1668 unsigned long chunk;
1670 for (chunk = s; chunk <= e; chunk++) {
1671 sector_t sec = (sector_t)chunk << CHUNK_BLOCK_SHIFT(bitmap);
1672 bitmap_set_memory_bits(bitmap, sec, 1);
1673 bitmap_file_set_bit(bitmap, sec);
1674 if (sec < bitmap->mddev->recovery_cp)
1675 /* We are asserting that the array is dirty,
1676 * so move the recovery_cp address back so
1677 * that it is obvious that it is dirty
1679 bitmap->mddev->recovery_cp = sec;
1684 * flush out any pending updates
1686 void bitmap_flush(mddev_t *mddev)
1688 struct bitmap *bitmap = mddev->bitmap;
1691 if (!bitmap) /* there was no bitmap */
1694 /* run the daemon_work three time to ensure everything is flushed
1697 sleep = mddev->bitmap_info.daemon_sleep * 2;
1698 bitmap->daemon_lastrun -= sleep;
1699 bitmap_daemon_work(mddev);
1700 bitmap->daemon_lastrun -= sleep;
1701 bitmap_daemon_work(mddev);
1702 bitmap->daemon_lastrun -= sleep;
1703 bitmap_daemon_work(mddev);
1704 bitmap_update_sb(bitmap);
1708 * free memory that was allocated
1710 static void bitmap_free(struct bitmap *bitmap)
1712 unsigned long k, pages;
1713 struct bitmap_page *bp;
1715 if (!bitmap) /* there was no bitmap */
1718 /* release the bitmap file and kill the daemon */
1719 bitmap_file_put(bitmap);
1722 pages = bitmap->pages;
1724 /* free all allocated memory */
1726 if (bp) /* deallocate the page memory */
1727 for (k = 0; k < pages; k++)
1728 if (bp[k].map && !bp[k].hijacked)
1734 void bitmap_destroy(mddev_t *mddev)
1736 struct bitmap *bitmap = mddev->bitmap;
1738 if (!bitmap) /* there was no bitmap */
1741 mutex_lock(&mddev->bitmap_info.mutex);
1742 mddev->bitmap = NULL; /* disconnect from the md device */
1743 mutex_unlock(&mddev->bitmap_info.mutex);
1745 mddev->thread->timeout = MAX_SCHEDULE_TIMEOUT;
1747 if (bitmap->sysfs_can_clear)
1748 sysfs_put(bitmap->sysfs_can_clear);
1750 bitmap_free(bitmap);
1754 * initialize the bitmap structure
1755 * if this returns an error, bitmap_destroy must be called to do clean up
1757 int bitmap_create(mddev_t *mddev)
1759 struct bitmap *bitmap;
1760 sector_t blocks = mddev->resync_max_sectors;
1761 unsigned long chunks;
1762 unsigned long pages;
1763 struct file *file = mddev->bitmap_info.file;
1765 struct sysfs_dirent *bm = NULL;
1767 BUILD_BUG_ON(sizeof(bitmap_super_t) != 256);
1770 && !mddev->bitmap_info.offset
1771 && !mddev->bitmap_info.log) /* bitmap disabled, nothing to do */
1774 BUG_ON(file && mddev->bitmap_info.offset);
1775 BUG_ON(mddev->bitmap_info.offset && mddev->bitmap_info.log);
1777 bitmap = kzalloc(sizeof(*bitmap), GFP_KERNEL);
1781 spin_lock_init(&bitmap->lock);
1782 atomic_set(&bitmap->pending_writes, 0);
1783 init_waitqueue_head(&bitmap->write_wait);
1784 init_waitqueue_head(&bitmap->overflow_wait);
1785 init_waitqueue_head(&bitmap->behind_wait);
1787 bitmap->mddev = mddev;
1790 bm = sysfs_get_dirent(mddev->kobj.sd, NULL, "bitmap");
1792 bitmap->sysfs_can_clear = sysfs_get_dirent(bm, NULL, "can_clear");
1795 bitmap->sysfs_can_clear = NULL;
1797 bitmap->file = file;
1800 /* As future accesses to this file will use bmap,
1801 * and bypass the page cache, we must sync the file
1806 /* read superblock from bitmap file (this sets mddev->bitmap_info.chunksize) */
1807 if (!mddev->bitmap_info.external) {
1809 * If 'MD_ARRAY_FIRST_USE' is set, then device-mapper is
1810 * instructing us to create a new on-disk bitmap instance.
1812 if (test_and_clear_bit(MD_ARRAY_FIRST_USE, &mddev->flags))
1813 err = bitmap_new_disk_sb(bitmap);
1815 err = bitmap_read_sb(bitmap);
1818 if (mddev->bitmap_info.chunksize == 0 ||
1819 mddev->bitmap_info.daemon_sleep == 0)
1820 /* chunksize and time_base need to be
1827 bitmap->daemon_lastrun = jiffies;
1828 bitmap->chunkshift = ffz(~mddev->bitmap_info.chunksize);
1830 /* now that chunksize and chunkshift are set, we can use these macros */
1831 chunks = (blocks + CHUNK_BLOCK_RATIO(bitmap) - 1) >>
1832 CHUNK_BLOCK_SHIFT(bitmap);
1833 pages = (chunks + PAGE_COUNTER_RATIO - 1) / PAGE_COUNTER_RATIO;
1837 bitmap->chunks = chunks;
1838 bitmap->pages = pages;
1839 bitmap->missing_pages = pages;
1841 #ifdef INJECT_FATAL_FAULT_1
1844 bitmap->bp = kzalloc(pages * sizeof(*bitmap->bp), GFP_KERNEL);
1850 printk(KERN_INFO "created bitmap (%lu pages) for device %s\n",
1851 pages, bmname(bitmap));
1853 mddev->bitmap = bitmap;
1856 return (bitmap->flags & BITMAP_WRITE_ERROR) ? -EIO : 0;
1859 bitmap_free(bitmap);
1863 int bitmap_load(mddev_t *mddev)
1866 sector_t sector = 0;
1867 struct bitmap *bitmap = mddev->bitmap;
1872 /* Clear out old bitmap info first: Either there is none, or we
1873 * are resuming after someone else has possibly changed things,
1874 * so we should forget old cached info.
1875 * All chunks should be clean, but some might need_sync.
1877 while (sector < mddev->resync_max_sectors) {
1879 bitmap_start_sync(bitmap, sector, &blocks, 0);
1882 bitmap_close_sync(bitmap);
1884 if (mddev->bitmap_info.log) {
1886 struct dm_dirty_log *log = mddev->bitmap_info.log;
1887 for (i = 0; i < bitmap->chunks; i++)
1888 if (!log->type->in_sync(log, i, 1))
1889 bitmap_set_memory_bits(bitmap,
1890 (sector_t)i << CHUNK_BLOCK_SHIFT(bitmap),
1894 if (mddev->degraded == 0
1895 || bitmap->events_cleared == mddev->events)
1896 /* no need to keep dirty bits to optimise a
1897 * re-add of a missing device */
1898 start = mddev->recovery_cp;
1900 mutex_lock(&mddev->bitmap_info.mutex);
1901 err = bitmap_init_from_disk(bitmap, start);
1902 mutex_unlock(&mddev->bitmap_info.mutex);
1907 mddev->thread->timeout = mddev->bitmap_info.daemon_sleep;
1908 md_wakeup_thread(mddev->thread);
1910 bitmap_update_sb(bitmap);
1912 if (bitmap->flags & BITMAP_WRITE_ERROR)
1917 EXPORT_SYMBOL_GPL(bitmap_load);
1920 location_show(mddev_t *mddev, char *page)
1923 if (mddev->bitmap_info.file)
1924 len = sprintf(page, "file");
1925 else if (mddev->bitmap_info.offset)
1926 len = sprintf(page, "%+lld", (long long)mddev->bitmap_info.offset);
1928 len = sprintf(page, "none");
1929 len += sprintf(page+len, "\n");
1934 location_store(mddev_t *mddev, const char *buf, size_t len)
1938 if (!mddev->pers->quiesce)
1940 if (mddev->recovery || mddev->sync_thread)
1944 if (mddev->bitmap || mddev->bitmap_info.file ||
1945 mddev->bitmap_info.offset) {
1946 /* bitmap already configured. Only option is to clear it */
1947 if (strncmp(buf, "none", 4) != 0)
1950 mddev->pers->quiesce(mddev, 1);
1951 bitmap_destroy(mddev);
1952 mddev->pers->quiesce(mddev, 0);
1954 mddev->bitmap_info.offset = 0;
1955 if (mddev->bitmap_info.file) {
1956 struct file *f = mddev->bitmap_info.file;
1957 mddev->bitmap_info.file = NULL;
1958 restore_bitmap_write_access(f);
1962 /* No bitmap, OK to set a location */
1964 if (strncmp(buf, "none", 4) == 0)
1965 /* nothing to be done */;
1966 else if (strncmp(buf, "file:", 5) == 0) {
1967 /* Not supported yet */
1972 rv = strict_strtoll(buf+1, 10, &offset);
1974 rv = strict_strtoll(buf, 10, &offset);
1979 if (mddev->bitmap_info.external == 0 &&
1980 mddev->major_version == 0 &&
1981 offset != mddev->bitmap_info.default_offset)
1983 mddev->bitmap_info.offset = offset;
1985 mddev->pers->quiesce(mddev, 1);
1986 rv = bitmap_create(mddev);
1988 rv = bitmap_load(mddev);
1990 bitmap_destroy(mddev);
1991 mddev->bitmap_info.offset = 0;
1993 mddev->pers->quiesce(mddev, 0);
1999 if (!mddev->external) {
2000 /* Ensure new bitmap info is stored in
2001 * metadata promptly.
2003 set_bit(MD_CHANGE_DEVS, &mddev->flags);
2004 md_wakeup_thread(mddev->thread);
2009 static struct md_sysfs_entry bitmap_location =
2010 __ATTR(location, S_IRUGO|S_IWUSR, location_show, location_store);
2013 timeout_show(mddev_t *mddev, char *page)
2016 unsigned long secs = mddev->bitmap_info.daemon_sleep / HZ;
2017 unsigned long jifs = mddev->bitmap_info.daemon_sleep % HZ;
2019 len = sprintf(page, "%lu", secs);
2021 len += sprintf(page+len, ".%03u", jiffies_to_msecs(jifs));
2022 len += sprintf(page+len, "\n");
2027 timeout_store(mddev_t *mddev, const char *buf, size_t len)
2029 /* timeout can be set at any time */
2030 unsigned long timeout;
2031 int rv = strict_strtoul_scaled(buf, &timeout, 4);
2035 /* just to make sure we don't overflow... */
2036 if (timeout >= LONG_MAX / HZ)
2039 timeout = timeout * HZ / 10000;
2041 if (timeout >= MAX_SCHEDULE_TIMEOUT)
2042 timeout = MAX_SCHEDULE_TIMEOUT-1;
2045 mddev->bitmap_info.daemon_sleep = timeout;
2046 if (mddev->thread) {
2047 /* if thread->timeout is MAX_SCHEDULE_TIMEOUT, then
2048 * the bitmap is all clean and we don't need to
2049 * adjust the timeout right now
2051 if (mddev->thread->timeout < MAX_SCHEDULE_TIMEOUT) {
2052 mddev->thread->timeout = timeout;
2053 md_wakeup_thread(mddev->thread);
2059 static struct md_sysfs_entry bitmap_timeout =
2060 __ATTR(time_base, S_IRUGO|S_IWUSR, timeout_show, timeout_store);
2063 backlog_show(mddev_t *mddev, char *page)
2065 return sprintf(page, "%lu\n", mddev->bitmap_info.max_write_behind);
2069 backlog_store(mddev_t *mddev, const char *buf, size_t len)
2071 unsigned long backlog;
2072 int rv = strict_strtoul(buf, 10, &backlog);
2075 if (backlog > COUNTER_MAX)
2077 mddev->bitmap_info.max_write_behind = backlog;
2081 static struct md_sysfs_entry bitmap_backlog =
2082 __ATTR(backlog, S_IRUGO|S_IWUSR, backlog_show, backlog_store);
2085 chunksize_show(mddev_t *mddev, char *page)
2087 return sprintf(page, "%lu\n", mddev->bitmap_info.chunksize);
2091 chunksize_store(mddev_t *mddev, const char *buf, size_t len)
2093 /* Can only be changed when no bitmap is active */
2095 unsigned long csize;
2098 rv = strict_strtoul(buf, 10, &csize);
2102 !is_power_of_2(csize))
2104 mddev->bitmap_info.chunksize = csize;
2108 static struct md_sysfs_entry bitmap_chunksize =
2109 __ATTR(chunksize, S_IRUGO|S_IWUSR, chunksize_show, chunksize_store);
2111 static ssize_t metadata_show(mddev_t *mddev, char *page)
2113 return sprintf(page, "%s\n", (mddev->bitmap_info.external
2114 ? "external" : "internal"));
2117 static ssize_t metadata_store(mddev_t *mddev, const char *buf, size_t len)
2119 if (mddev->bitmap ||
2120 mddev->bitmap_info.file ||
2121 mddev->bitmap_info.offset)
2123 if (strncmp(buf, "external", 8) == 0)
2124 mddev->bitmap_info.external = 1;
2125 else if (strncmp(buf, "internal", 8) == 0)
2126 mddev->bitmap_info.external = 0;
2132 static struct md_sysfs_entry bitmap_metadata =
2133 __ATTR(metadata, S_IRUGO|S_IWUSR, metadata_show, metadata_store);
2135 static ssize_t can_clear_show(mddev_t *mddev, char *page)
2139 len = sprintf(page, "%s\n", (mddev->bitmap->need_sync ?
2142 len = sprintf(page, "\n");
2146 static ssize_t can_clear_store(mddev_t *mddev, const char *buf, size_t len)
2148 if (mddev->bitmap == NULL)
2150 if (strncmp(buf, "false", 5) == 0)
2151 mddev->bitmap->need_sync = 1;
2152 else if (strncmp(buf, "true", 4) == 0) {
2153 if (mddev->degraded)
2155 mddev->bitmap->need_sync = 0;
2161 static struct md_sysfs_entry bitmap_can_clear =
2162 __ATTR(can_clear, S_IRUGO|S_IWUSR, can_clear_show, can_clear_store);
2165 behind_writes_used_show(mddev_t *mddev, char *page)
2167 if (mddev->bitmap == NULL)
2168 return sprintf(page, "0\n");
2169 return sprintf(page, "%lu\n",
2170 mddev->bitmap->behind_writes_used);
2174 behind_writes_used_reset(mddev_t *mddev, const char *buf, size_t len)
2177 mddev->bitmap->behind_writes_used = 0;
2181 static struct md_sysfs_entry max_backlog_used =
2182 __ATTR(max_backlog_used, S_IRUGO | S_IWUSR,
2183 behind_writes_used_show, behind_writes_used_reset);
2185 static struct attribute *md_bitmap_attrs[] = {
2186 &bitmap_location.attr,
2187 &bitmap_timeout.attr,
2188 &bitmap_backlog.attr,
2189 &bitmap_chunksize.attr,
2190 &bitmap_metadata.attr,
2191 &bitmap_can_clear.attr,
2192 &max_backlog_used.attr,
2195 struct attribute_group md_bitmap_group = {
2197 .attrs = md_bitmap_attrs,