* additions, Copyright (C) 2003-2004, Paul Clements, SteelEye Technology, Inc.:
* - added disk storage for bitmap
* - changes to allow various bitmap chunk sizes
- * - added bitmap daemon (to asynchronously clear bitmap bits from disk)
*/
/*
*
* flush after percent set rather than just time based. (maybe both).
* wait if count gets too high, wake when it drops to half.
- * allow bitmap to be mirrored with superblock (before or after...)
- * allow hot-add to re-instate a current device.
- * allow hot-add of bitmap after quiessing device
*/
+#include <linux/blkdev.h>
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/init.h>
-#include <linux/config.h>
#include <linux/timer.h>
#include <linux/sched.h>
#include <linux/list.h>
#include <linux/file.h>
#include <linux/mount.h>
#include <linux/buffer_head.h>
-#include <linux/raid/md.h>
-#include <linux/raid/bitmap.h>
+#include "md.h"
+#include "bitmap.h"
/* debug macros */
/*
- * test if the bitmap is active
- */
-int bitmap_active(struct bitmap *bitmap)
-{
- unsigned long flags;
- int res = 0;
-
- if (!bitmap)
- return res;
- spin_lock_irqsave(&bitmap->lock, flags);
- res = bitmap->flags & BITMAP_ACTIVE;
- spin_unlock_irqrestore(&bitmap->lock, flags);
- return res;
-}
-
-#define WRITE_POOL_SIZE 256
-/* mempool for queueing pending writes on the bitmap file */
-static void *write_pool_alloc(gfp_t gfp_flags, void *data)
-{
- return kmalloc(sizeof(struct page_list), gfp_flags);
-}
-
-static void write_pool_free(void *ptr, void *data)
-{
- kfree(ptr);
-}
-
-/*
* just a placeholder - calls kmalloc for bitmap pages
*/
static unsigned char *bitmap_alloc_page(struct bitmap *bitmap)
* allocated while we're using it
*/
static int bitmap_checkpage(struct bitmap *bitmap, unsigned long page, int create)
+__releases(bitmap->lock)
+__acquires(bitmap->lock)
{
unsigned char *mappage;
if (page >= bitmap->pages) {
- printk(KERN_ALERT
- "%s: invalid bitmap page request: %lu (> %lu)\n",
- bmname(bitmap), page, bitmap->pages-1);
+ /* This can happen if bitmap_start_sync goes beyond
+ * End-of-device while looking for a whole page.
+ * It is harmless.
+ */
return -EINVAL;
}
/* if page is completely empty, put it back on the free list, or dealloc it */
/* if page was hijacked, unmark the flag so it might get alloced next time */
/* Note: lock should be held when calling this */
-static inline void bitmap_checkfree(struct bitmap *bitmap, unsigned long page)
+static void bitmap_checkfree(struct bitmap *bitmap, unsigned long page)
{
char *ptr;
* bitmap file handling - read and write the bitmap file and its superblock
*/
-/* copy the pathname of a file to a buffer */
-char *file_path(struct file *file, char *buf, int count)
-{
- struct dentry *d;
- struct vfsmount *v;
-
- if (!buf)
- return NULL;
-
- d = file->f_dentry;
- v = file->f_vfsmnt;
-
- buf = d_path(d, v, buf, count);
-
- return IS_ERR(buf) ? NULL : buf;
-}
-
/*
* basic page I/O operations
*/
/* IO operations when bitmap is stored near all superblocks */
-static struct page *read_sb_page(mddev_t *mddev, long offset, unsigned long index)
+static struct page *read_sb_page(mddev_t *mddev, loff_t offset,
+ struct page *page,
+ unsigned long index, int size)
{
/* choose a good rdev and read the page from there */
mdk_rdev_t *rdev;
- struct list_head *tmp;
- struct page *page = alloc_page(GFP_KERNEL);
sector_t target;
if (!page)
+ page = alloc_page(GFP_KERNEL);
+ if (!page)
return ERR_PTR(-ENOMEM);
- ITERATE_RDEV(mddev, rdev, tmp) {
+ list_for_each_entry(rdev, &mddev->disks, same_set) {
if (! test_bit(In_sync, &rdev->flags)
|| test_bit(Faulty, &rdev->flags))
continue;
- target = (rdev->sb_offset << 1) + offset + index * (PAGE_SIZE/512);
+ target = rdev->sb_start + offset + index * (PAGE_SIZE/512);
- if (sync_page_io(rdev->bdev, target, PAGE_SIZE, page, READ)) {
+ if (sync_page_io(rdev->bdev, target,
+ roundup(size, bdev_logical_block_size(rdev->bdev)),
+ page, READ)) {
page->index = index;
+ attach_page_buffers(page, NULL); /* so that free_buffer will
+ * quietly no-op */
return page;
}
}
}
-static int write_sb_page(mddev_t *mddev, long offset, struct page *page, int wait)
+static mdk_rdev_t *next_active_rdev(mdk_rdev_t *rdev, mddev_t *mddev)
{
- mdk_rdev_t *rdev;
- struct list_head *tmp;
+ /* Iterate the disks of an mddev, using rcu to protect access to the
+ * linked list, and raising the refcount of devices we return to ensure
+ * they don't disappear while in use.
+ * As devices are only added or removed when raid_disk is < 0 and
+ * nr_pending is 0 and In_sync is clear, the entries we return will
+ * still be in the same position on the list when we re-enter
+ * list_for_each_continue_rcu.
+ */
+ struct list_head *pos;
+ rcu_read_lock();
+ if (rdev == NULL)
+ /* start at the beginning */
+ pos = &mddev->disks;
+ else {
+ /* release the previous rdev and start from there. */
+ rdev_dec_pending(rdev, mddev);
+ pos = &rdev->same_set;
+ }
+ list_for_each_continue_rcu(pos, &mddev->disks) {
+ rdev = list_entry(pos, mdk_rdev_t, same_set);
+ if (rdev->raid_disk >= 0 &&
+ !test_bit(Faulty, &rdev->flags)) {
+ /* this is a usable devices */
+ atomic_inc(&rdev->nr_pending);
+ rcu_read_unlock();
+ return rdev;
+ }
+ }
+ rcu_read_unlock();
+ return NULL;
+}
- ITERATE_RDEV(mddev, rdev, tmp)
- if (test_bit(In_sync, &rdev->flags)
- && !test_bit(Faulty, &rdev->flags))
+static int write_sb_page(struct bitmap *bitmap, struct page *page, int wait)
+{
+ mdk_rdev_t *rdev = NULL;
+ mddev_t *mddev = bitmap->mddev;
+
+ while ((rdev = next_active_rdev(rdev, mddev)) != NULL) {
+ int size = PAGE_SIZE;
+ loff_t offset = mddev->bitmap_info.offset;
+ if (page->index == bitmap->file_pages-1)
+ size = roundup(bitmap->last_page_size,
+ bdev_logical_block_size(rdev->bdev));
+ /* Just make sure we aren't corrupting data or
+ * metadata
+ */
+ if (mddev->external) {
+ /* Bitmap could be anywhere. */
+ if (rdev->sb_start + offset + (page->index *(PAGE_SIZE/512)) >
+ rdev->data_offset &&
+ rdev->sb_start + offset <
+ rdev->data_offset + mddev->dev_sectors +
+ (PAGE_SIZE/512))
+ goto bad_alignment;
+ } else if (offset < 0) {
+ /* DATA BITMAP METADATA */
+ if (offset
+ + (long)(page->index * (PAGE_SIZE/512))
+ + size/512 > 0)
+ /* bitmap runs in to metadata */
+ goto bad_alignment;
+ if (rdev->data_offset + mddev->dev_sectors
+ > rdev->sb_start + offset)
+ /* data runs in to bitmap */
+ goto bad_alignment;
+ } else if (rdev->sb_start < rdev->data_offset) {
+ /* METADATA BITMAP DATA */
+ if (rdev->sb_start
+ + offset
+ + page->index*(PAGE_SIZE/512) + size/512
+ > rdev->data_offset)
+ /* bitmap runs in to data */
+ goto bad_alignment;
+ } else {
+ /* DATA METADATA BITMAP - no problems */
+ }
md_super_write(mddev, rdev,
- (rdev->sb_offset<<1) + offset
+ rdev->sb_start + offset
+ page->index * (PAGE_SIZE/512),
- PAGE_SIZE,
+ size,
page);
+ }
if (wait)
- wait_event(mddev->sb_wait, atomic_read(&mddev->pending_writes)==0);
+ md_super_wait(mddev);
return 0;
+
+ bad_alignment:
+ return -EINVAL;
}
+static void bitmap_file_kick(struct bitmap *bitmap);
/*
* write out a page to a file
*/
-static int write_page(struct bitmap *bitmap, struct page *page, int wait)
+static void write_page(struct bitmap *bitmap, struct page *page, int wait)
{
- int ret = -ENOMEM;
+ struct buffer_head *bh;
- if (bitmap->file == NULL)
- return write_sb_page(bitmap->mddev, bitmap->offset, page, wait);
+ if (bitmap->file == NULL) {
+ switch (write_sb_page(bitmap, page, wait)) {
+ case -EINVAL:
+ bitmap->flags |= BITMAP_WRITE_ERROR;
+ }
+ } else {
- if (wait)
- lock_page(page);
- else {
- if (TestSetPageLocked(page))
- return -EAGAIN; /* already locked */
- if (PageWriteback(page)) {
- unlock_page(page);
- return -EAGAIN;
+ bh = page_buffers(page);
+
+ while (bh && bh->b_blocknr) {
+ atomic_inc(&bitmap->pending_writes);
+ set_buffer_locked(bh);
+ set_buffer_mapped(bh);
+ submit_bh(WRITE, bh);
+ bh = bh->b_this_page;
+ }
+
+ if (wait) {
+ wait_event(bitmap->write_wait,
+ atomic_read(&bitmap->pending_writes)==0);
}
}
+ if (bitmap->flags & BITMAP_WRITE_ERROR)
+ bitmap_file_kick(bitmap);
+}
+
+static void end_bitmap_write(struct buffer_head *bh, int uptodate)
+{
+ struct bitmap *bitmap = bh->b_private;
+ unsigned long flags;
- ret = page->mapping->a_ops->prepare_write(NULL, page, 0, PAGE_SIZE);
- if (!ret)
- ret = page->mapping->a_ops->commit_write(NULL, page, 0,
- PAGE_SIZE);
- if (ret) {
- unlock_page(page);
- return ret;
+ if (!uptodate) {
+ spin_lock_irqsave(&bitmap->lock, flags);
+ bitmap->flags |= BITMAP_WRITE_ERROR;
+ spin_unlock_irqrestore(&bitmap->lock, flags);
}
+ if (atomic_dec_and_test(&bitmap->pending_writes))
+ wake_up(&bitmap->write_wait);
+}
+
+/* copied from buffer.c */
+static void
+__clear_page_buffers(struct page *page)
+{
+ ClearPagePrivate(page);
+ set_page_private(page, 0);
+ page_cache_release(page);
+}
+static void free_buffers(struct page *page)
+{
+ struct buffer_head *bh = page_buffers(page);
- set_page_dirty(page); /* force it to be written out */
-
- if (!wait) {
- /* add to list to be waited for by daemon */
- struct page_list *item = mempool_alloc(bitmap->write_pool, GFP_NOIO);
- item->page = page;
- page_cache_get(page);
- spin_lock(&bitmap->write_lock);
- list_add(&item->list, &bitmap->complete_pages);
- spin_unlock(&bitmap->write_lock);
- md_wakeup_thread(bitmap->writeback_daemon);
+ while (bh) {
+ struct buffer_head *next = bh->b_this_page;
+ free_buffer_head(bh);
+ bh = next;
}
- return write_one_page(page, wait);
+ __clear_page_buffers(page);
+ put_page(page);
}
-/* read a page from a file, pinning it into cache, and return bytes_read */
+/* read a page from a file.
+ * We both read the page, and attach buffers to the page to record the
+ * address of each block (using bmap). These addresses will be used
+ * to write the block later, completely bypassing the filesystem.
+ * This usage is similar to how swap files are handled, and allows us
+ * to write to a file with no concerns of memory allocation failing.
+ */
static struct page *read_page(struct file *file, unsigned long index,
- unsigned long *bytes_read)
+ struct bitmap *bitmap,
+ unsigned long count)
{
- struct inode *inode = file->f_mapping->host;
struct page *page = NULL;
- loff_t isize = i_size_read(inode);
- unsigned long end_index = isize >> PAGE_CACHE_SHIFT;
+ struct inode *inode = file->f_path.dentry->d_inode;
+ struct buffer_head *bh;
+ sector_t block;
- PRINTK("read bitmap file (%dB @ %Lu)\n", (int)PAGE_CACHE_SIZE,
- (unsigned long long)index << PAGE_CACHE_SHIFT);
+ PRINTK("read bitmap file (%dB @ %Lu)\n", (int)PAGE_SIZE,
+ (unsigned long long)index << PAGE_SHIFT);
- page = read_cache_page(inode->i_mapping, index,
- (filler_t *)inode->i_mapping->a_ops->readpage, file);
+ page = alloc_page(GFP_KERNEL);
+ if (!page)
+ page = ERR_PTR(-ENOMEM);
if (IS_ERR(page))
goto out;
- wait_on_page_locked(page);
- if (!PageUptodate(page) || PageError(page)) {
- page_cache_release(page);
- page = ERR_PTR(-EIO);
+
+ bh = alloc_page_buffers(page, 1<<inode->i_blkbits, 0);
+ if (!bh) {
+ put_page(page);
+ page = ERR_PTR(-ENOMEM);
goto out;
}
+ attach_page_buffers(page, bh);
+ block = index << (PAGE_SHIFT - inode->i_blkbits);
+ while (bh) {
+ if (count == 0)
+ bh->b_blocknr = 0;
+ else {
+ bh->b_blocknr = bmap(inode, block);
+ if (bh->b_blocknr == 0) {
+ /* Cannot use this file! */
+ free_buffers(page);
+ page = ERR_PTR(-EINVAL);
+ goto out;
+ }
+ bh->b_bdev = inode->i_sb->s_bdev;
+ if (count < (1<<inode->i_blkbits))
+ count = 0;
+ else
+ count -= (1<<inode->i_blkbits);
+
+ bh->b_end_io = end_bitmap_write;
+ bh->b_private = bitmap;
+ atomic_inc(&bitmap->pending_writes);
+ set_buffer_locked(bh);
+ set_buffer_mapped(bh);
+ submit_bh(READ, bh);
+ }
+ block++;
+ bh = bh->b_this_page;
+ }
+ page->index = index;
- if (index > end_index) /* we have read beyond EOF */
- *bytes_read = 0;
- else if (index == end_index) /* possible short read */
- *bytes_read = isize & ~PAGE_CACHE_MASK;
- else
- *bytes_read = PAGE_CACHE_SIZE; /* got a full page */
+ wait_event(bitmap->write_wait,
+ atomic_read(&bitmap->pending_writes)==0);
+ if (bitmap->flags & BITMAP_WRITE_ERROR) {
+ free_buffers(page);
+ page = ERR_PTR(-EIO);
+ }
out:
if (IS_ERR(page))
printk(KERN_ALERT "md: bitmap read error: (%dB @ %Lu): %ld\n",
- (int)PAGE_CACHE_SIZE,
- (unsigned long long)index << PAGE_CACHE_SHIFT,
+ (int)PAGE_SIZE,
+ (unsigned long long)index << PAGE_SHIFT,
PTR_ERR(page));
return page;
}
*/
/* update the event counter and sync the superblock to disk */
-int bitmap_update_sb(struct bitmap *bitmap)
+void bitmap_update_sb(struct bitmap *bitmap)
{
bitmap_super_t *sb;
unsigned long flags;
if (!bitmap || !bitmap->mddev) /* no bitmap for this array */
- return 0;
+ return;
+ if (bitmap->mddev->bitmap_info.external)
+ return;
spin_lock_irqsave(&bitmap->lock, flags);
if (!bitmap->sb_page) { /* no superblock */
spin_unlock_irqrestore(&bitmap->lock, flags);
- return 0;
+ return;
}
spin_unlock_irqrestore(&bitmap->lock, flags);
- sb = (bitmap_super_t *)kmap(bitmap->sb_page);
+ sb = (bitmap_super_t *)kmap_atomic(bitmap->sb_page, KM_USER0);
sb->events = cpu_to_le64(bitmap->mddev->events);
- if (!bitmap->mddev->degraded)
- sb->events_cleared = cpu_to_le64(bitmap->mddev->events);
- kunmap(bitmap->sb_page);
- return write_page(bitmap, bitmap->sb_page, 1);
+ if (bitmap->mddev->events < bitmap->events_cleared) {
+ /* rocking back to read-only */
+ bitmap->events_cleared = bitmap->mddev->events;
+ sb->events_cleared = cpu_to_le64(bitmap->events_cleared);
+ }
+ /* Just in case these have been changed via sysfs: */
+ sb->daemon_sleep = cpu_to_le32(bitmap->mddev->bitmap_info.daemon_sleep/HZ);
+ sb->write_behind = cpu_to_le32(bitmap->mddev->bitmap_info.max_write_behind);
+ kunmap_atomic(sb, KM_USER0);
+ write_page(bitmap, bitmap->sb_page, 1);
}
/* print out the bitmap file superblock */
if (!bitmap || !bitmap->sb_page)
return;
- sb = (bitmap_super_t *)kmap(bitmap->sb_page);
+ sb = (bitmap_super_t *)kmap_atomic(bitmap->sb_page, KM_USER0);
printk(KERN_DEBUG "%s: bitmap file superblock:\n", bmname(bitmap));
printk(KERN_DEBUG " magic: %08x\n", le32_to_cpu(sb->magic));
printk(KERN_DEBUG " version: %d\n", le32_to_cpu(sb->version));
printk(KERN_DEBUG " sync size: %llu KB\n",
(unsigned long long)le64_to_cpu(sb->sync_size)/2);
printk(KERN_DEBUG "max write behind: %d\n", le32_to_cpu(sb->write_behind));
- kunmap(bitmap->sb_page);
+ kunmap_atomic(sb, KM_USER0);
}
/* read the superblock from the bitmap file and initialize some bitmap fields */
char *reason = NULL;
bitmap_super_t *sb;
unsigned long chunksize, daemon_sleep, write_behind;
- unsigned long bytes_read;
unsigned long long events;
int err = -EINVAL;
/* page 0 is the superblock, read it... */
- if (bitmap->file)
- bitmap->sb_page = read_page(bitmap->file, 0, &bytes_read);
- else {
- bitmap->sb_page = read_sb_page(bitmap->mddev, bitmap->offset, 0);
- bytes_read = PAGE_SIZE;
+ if (bitmap->file) {
+ loff_t isize = i_size_read(bitmap->file->f_mapping->host);
+ int bytes = isize > PAGE_SIZE ? PAGE_SIZE : isize;
+
+ bitmap->sb_page = read_page(bitmap->file, 0, bitmap, bytes);
+ } else {
+ bitmap->sb_page = read_sb_page(bitmap->mddev,
+ bitmap->mddev->bitmap_info.offset,
+ NULL,
+ 0, sizeof(bitmap_super_t));
}
if (IS_ERR(bitmap->sb_page)) {
err = PTR_ERR(bitmap->sb_page);
return err;
}
- sb = (bitmap_super_t *)kmap(bitmap->sb_page);
-
- if (bytes_read < sizeof(*sb)) { /* short read */
- printk(KERN_INFO "%s: bitmap file superblock truncated\n",
- bmname(bitmap));
- err = -ENOSPC;
- goto out;
- }
+ sb = (bitmap_super_t *)kmap_atomic(bitmap->sb_page, KM_USER0);
chunksize = le32_to_cpu(sb->chunksize);
- daemon_sleep = le32_to_cpu(sb->daemon_sleep);
+ daemon_sleep = le32_to_cpu(sb->daemon_sleep) * HZ;
write_behind = le32_to_cpu(sb->write_behind);
/* verify that the bitmap-specific fields are valid */
else if (le32_to_cpu(sb->version) < BITMAP_MAJOR_LO ||
le32_to_cpu(sb->version) > BITMAP_MAJOR_HI)
reason = "unrecognized superblock version";
- else if (chunksize < 512 || chunksize > (1024 * 1024 * 4))
- reason = "bitmap chunksize out of range (512B - 4MB)";
+ else if (chunksize < 512)
+ reason = "bitmap chunksize too small";
else if ((1 << ffz(~chunksize)) != chunksize)
reason = "bitmap chunksize not a power of 2";
- else if (daemon_sleep < 1 || daemon_sleep > 15)
- reason = "daemon sleep period out of range (1-15s)";
+ else if (daemon_sleep < 1 || daemon_sleep > MAX_SCHEDULE_TIMEOUT)
+ reason = "daemon sleep period out of range";
else if (write_behind > COUNTER_MAX)
reason = "write-behind limit out of range (0 - 16383)";
if (reason) {
printk(KERN_INFO "%s: bitmap file is out of date (%llu < %llu) "
"-- forcing full recovery\n", bmname(bitmap), events,
(unsigned long long) bitmap->mddev->events);
- sb->state |= BITMAP_STALE;
+ sb->state |= cpu_to_le32(BITMAP_STALE);
}
success:
/* assign fields using values from superblock */
- bitmap->chunksize = chunksize;
- bitmap->daemon_sleep = daemon_sleep;
- bitmap->daemon_lastrun = jiffies;
- bitmap->max_write_behind = write_behind;
- bitmap->flags |= sb->state;
+ bitmap->mddev->bitmap_info.chunksize = chunksize;
+ bitmap->mddev->bitmap_info.daemon_sleep = daemon_sleep;
+ bitmap->mddev->bitmap_info.max_write_behind = write_behind;
+ bitmap->flags |= le32_to_cpu(sb->state);
if (le32_to_cpu(sb->version) == BITMAP_MAJOR_HOSTENDIAN)
bitmap->flags |= BITMAP_HOSTENDIAN;
bitmap->events_cleared = le64_to_cpu(sb->events_cleared);
- if (sb->state & BITMAP_STALE)
+ if (sb->state & cpu_to_le32(BITMAP_STALE))
bitmap->events_cleared = bitmap->mddev->events;
err = 0;
out:
- kunmap(bitmap->sb_page);
+ kunmap_atomic(sb, KM_USER0);
if (err)
bitmap_print_sb(bitmap);
return err;
MASK_UNSET
};
-/* record the state of the bitmap in the superblock */
-static void bitmap_mask_state(struct bitmap *bitmap, enum bitmap_state bits,
- enum bitmap_mask_op op)
+/* record the state of the bitmap in the superblock. Return the old value */
+static int bitmap_mask_state(struct bitmap *bitmap, enum bitmap_state bits,
+ enum bitmap_mask_op op)
{
bitmap_super_t *sb;
unsigned long flags;
+ int old;
spin_lock_irqsave(&bitmap->lock, flags);
- if (!bitmap || !bitmap->sb_page) { /* can't set the state */
+ if (!bitmap->sb_page) { /* can't set the state */
spin_unlock_irqrestore(&bitmap->lock, flags);
- return;
+ return 0;
}
- page_cache_get(bitmap->sb_page);
spin_unlock_irqrestore(&bitmap->lock, flags);
- sb = (bitmap_super_t *)kmap(bitmap->sb_page);
+ sb = (bitmap_super_t *)kmap_atomic(bitmap->sb_page, KM_USER0);
+ old = le32_to_cpu(sb->state) & bits;
switch (op) {
- case MASK_SET: sb->state |= bits;
+ case MASK_SET: sb->state |= cpu_to_le32(bits);
break;
- case MASK_UNSET: sb->state &= ~bits;
+ case MASK_UNSET: sb->state &= cpu_to_le32(~bits);
break;
default: BUG();
}
- kunmap(bitmap->sb_page);
- page_cache_release(bitmap->sb_page);
+ kunmap_atomic(sb, KM_USER0);
+ return old;
}
/*
* general bitmap file operations
*/
+/*
+ * on-disk bitmap:
+ *
+ * Use one bit per "chunk" (block set). We do the disk I/O on the bitmap
+ * file a page at a time. There's a superblock at the start of the file.
+ */
/* calculate the index of the page that contains this bit */
-static inline unsigned long file_page_index(unsigned long chunk)
+static inline unsigned long file_page_index(struct bitmap *bitmap, unsigned long chunk)
{
- return CHUNK_BIT_OFFSET(chunk) >> PAGE_BIT_SHIFT;
+ if (!bitmap->mddev->bitmap_info.external)
+ chunk += sizeof(bitmap_super_t) << 3;
+ return chunk >> PAGE_BIT_SHIFT;
}
/* calculate the (bit) offset of this bit within a page */
-static inline unsigned long file_page_offset(unsigned long chunk)
+static inline unsigned long file_page_offset(struct bitmap *bitmap, unsigned long chunk)
{
- return CHUNK_BIT_OFFSET(chunk) & (PAGE_BITS - 1);
+ if (!bitmap->mddev->bitmap_info.external)
+ chunk += sizeof(bitmap_super_t) << 3;
+ return chunk & (PAGE_BITS - 1);
}
/*
static inline struct page *filemap_get_page(struct bitmap *bitmap,
unsigned long chunk)
{
- return bitmap->filemap[file_page_index(chunk) - file_page_index(0)];
+ if (file_page_index(bitmap, chunk) >= bitmap->file_pages) return NULL;
+ return bitmap->filemap[file_page_index(bitmap, chunk)
+ - file_page_index(bitmap, 0)];
}
spin_unlock_irqrestore(&bitmap->lock, flags);
while (pages--)
- if (map[pages]->index != 0) /* 0 is sb_page, release it below */
- page_cache_release(map[pages]);
+ if (map[pages] != sb_page) /* 0 is sb_page, release it below */
+ free_buffers(map[pages]);
kfree(map);
kfree(attr);
if (sb_page)
- page_cache_release(sb_page);
-}
-
-static void bitmap_stop_daemon(struct bitmap *bitmap);
-
-/* dequeue the next item in a page list -- don't call from irq context */
-static struct page_list *dequeue_page(struct bitmap *bitmap)
-{
- struct page_list *item = NULL;
- struct list_head *head = &bitmap->complete_pages;
-
- spin_lock(&bitmap->write_lock);
- if (list_empty(head))
- goto out;
- item = list_entry(head->prev, struct page_list, list);
- list_del(head->prev);
-out:
- spin_unlock(&bitmap->write_lock);
- return item;
-}
-
-static void drain_write_queues(struct bitmap *bitmap)
-{
- struct page_list *item;
-
- while ((item = dequeue_page(bitmap))) {
- /* don't bother to wait */
- page_cache_release(item->page);
- mempool_free(item, bitmap->write_pool);
- }
-
- wake_up(&bitmap->write_wait);
+ free_buffers(sb_page);
}
static void bitmap_file_put(struct bitmap *bitmap)
{
struct file *file;
- struct inode *inode;
unsigned long flags;
spin_lock_irqsave(&bitmap->lock, flags);
bitmap->file = NULL;
spin_unlock_irqrestore(&bitmap->lock, flags);
- bitmap_stop_daemon(bitmap);
-
- drain_write_queues(bitmap);
-
+ if (file)
+ wait_event(bitmap->write_wait,
+ atomic_read(&bitmap->pending_writes)==0);
bitmap_file_unmap(bitmap);
if (file) {
- inode = file->f_mapping->host;
- spin_lock(&inode->i_lock);
- atomic_set(&inode->i_writecount, 1); /* allow writes again */
- spin_unlock(&inode->i_lock);
+ struct inode *inode = file->f_path.dentry->d_inode;
+ invalidate_mapping_pages(inode->i_mapping, 0, -1);
fput(file);
}
}
{
char *path, *ptr = NULL;
- bitmap_mask_state(bitmap, BITMAP_STALE, MASK_SET);
- bitmap_update_sb(bitmap);
+ if (bitmap_mask_state(bitmap, BITMAP_STALE, MASK_SET) == 0) {
+ bitmap_update_sb(bitmap);
- if (bitmap->file) {
- path = kmalloc(PAGE_SIZE, GFP_KERNEL);
- if (path)
- ptr = file_path(bitmap->file, path, PAGE_SIZE);
+ if (bitmap->file) {
+ path = kmalloc(PAGE_SIZE, GFP_KERNEL);
+ if (path)
+ ptr = d_path(&bitmap->file->f_path, path,
+ PAGE_SIZE);
- printk(KERN_ALERT "%s: kicking failed bitmap file %s from array!\n",
- bmname(bitmap), ptr ? ptr : "");
- kfree(path);
+ printk(KERN_ALERT
+ "%s: kicking failed bitmap file %s from array!\n",
+ bmname(bitmap), IS_ERR(ptr) ? "" : ptr);
+
+ kfree(path);
+ } else
+ printk(KERN_ALERT
+ "%s: disabling internal bitmap due to errors\n",
+ bmname(bitmap));
}
bitmap_file_put(bitmap);
}
enum bitmap_page_attr {
- BITMAP_PAGE_DIRTY = 1, // there are set bits that need to be synced
- BITMAP_PAGE_CLEAN = 2, // there are bits that might need to be cleared
- BITMAP_PAGE_NEEDWRITE=4, // there are cleared bits that need to be synced
+ BITMAP_PAGE_DIRTY = 0, // there are set bits that need to be synced
+ BITMAP_PAGE_CLEAN = 1, // there are bits that might need to be cleared
+ BITMAP_PAGE_NEEDWRITE=2, // there are cleared bits that need to be synced
};
static inline void set_page_attr(struct bitmap *bitmap, struct page *page,
enum bitmap_page_attr attr)
{
- bitmap->filemap_attr[page->index] |= attr;
+ __set_bit((page->index<<2) + attr, bitmap->filemap_attr);
}
static inline void clear_page_attr(struct bitmap *bitmap, struct page *page,
enum bitmap_page_attr attr)
{
- bitmap->filemap_attr[page->index] &= ~attr;
+ __clear_bit((page->index<<2) + attr, bitmap->filemap_attr);
}
-static inline unsigned long get_page_attr(struct bitmap *bitmap, struct page *page)
+static inline unsigned long test_page_attr(struct bitmap *bitmap, struct page *page,
+ enum bitmap_page_attr attr)
{
- return bitmap->filemap_attr[page->index];
+ return test_bit((page->index<<2) + attr, bitmap->filemap_attr);
}
/*
}
page = filemap_get_page(bitmap, chunk);
- bit = file_page_offset(chunk);
-
-
- /* make sure the page stays cached until it gets written out */
- if (! (get_page_attr(bitmap, page) & BITMAP_PAGE_DIRTY))
- page_cache_get(page);
+ if (!page) return;
+ bit = file_page_offset(bitmap, chunk);
/* set the bit */
kaddr = kmap_atomic(page, KM_USER0);
/* this gets called when the md device is ready to unplug its underlying
* (slave) device queues -- before we let any writes go down, we need to
* sync the dirty pages of the bitmap file to disk */
-int bitmap_unplug(struct bitmap *bitmap)
+void bitmap_unplug(struct bitmap *bitmap)
{
- unsigned long i, attr, flags;
+ unsigned long i, flags;
+ int dirty, need_write;
struct page *page;
int wait = 0;
- int err;
if (!bitmap)
- return 0;
+ return;
/* look at each page to see if there are any set bits that need to be
* flushed out to disk */
spin_lock_irqsave(&bitmap->lock, flags);
if (!bitmap->filemap) {
spin_unlock_irqrestore(&bitmap->lock, flags);
- return 0;
+ return;
}
page = bitmap->filemap[i];
- attr = get_page_attr(bitmap, page);
+ dirty = test_page_attr(bitmap, page, BITMAP_PAGE_DIRTY);
+ need_write = test_page_attr(bitmap, page, BITMAP_PAGE_NEEDWRITE);
clear_page_attr(bitmap, page, BITMAP_PAGE_DIRTY);
clear_page_attr(bitmap, page, BITMAP_PAGE_NEEDWRITE);
- if ((attr & BITMAP_PAGE_DIRTY))
+ if (dirty)
wait = 1;
spin_unlock_irqrestore(&bitmap->lock, flags);
- if (attr & (BITMAP_PAGE_DIRTY | BITMAP_PAGE_NEEDWRITE)) {
- err = write_page(bitmap, page, 0);
- if (err == -EAGAIN) {
- if (attr & BITMAP_PAGE_DIRTY)
- err = write_page(bitmap, page, 1);
- else
- err = 0;
- }
- if (err)
- return 1;
- }
+ if (dirty | need_write)
+ write_page(bitmap, page, 0);
}
if (wait) { /* if any writes were performed, we need to wait on them */
- if (bitmap->file) {
- spin_lock_irq(&bitmap->write_lock);
- wait_event_lock_irq(bitmap->write_wait,
- list_empty(&bitmap->complete_pages), bitmap->write_lock,
- wake_up_process(bitmap->writeback_daemon->tsk));
- spin_unlock_irq(&bitmap->write_lock);
- } else
- wait_event(bitmap->mddev->sb_wait,
- atomic_read(&bitmap->mddev->pending_writes)==0);
+ if (bitmap->file)
+ wait_event(bitmap->write_wait,
+ atomic_read(&bitmap->pending_writes)==0);
+ else
+ md_super_wait(bitmap->mddev);
}
- return 0;
+ if (bitmap->flags & BITMAP_WRITE_ERROR)
+ bitmap_file_kick(bitmap);
}
static void bitmap_set_memory_bits(struct bitmap *bitmap, sector_t offset, int needed);
struct page *page = NULL, *oldpage = NULL;
unsigned long num_pages, bit_cnt = 0;
struct file *file;
- unsigned long bytes, offset, dummy;
+ unsigned long bytes, offset;
int outofdate;
int ret = -ENOSPC;
+ void *paddr;
chunks = bitmap->chunks;
file = bitmap->file;
- BUG_ON(!file && !bitmap->offset);
+ BUG_ON(!file && !bitmap->mddev->bitmap_info.offset);
#ifdef INJECT_FAULTS_3
outofdate = 1;
"recovery\n", bmname(bitmap));
bytes = (chunks + 7) / 8;
+ if (!bitmap->mddev->bitmap_info.external)
+ bytes += sizeof(bitmap_super_t);
- num_pages = (bytes + sizeof(bitmap_super_t) + PAGE_SIZE - 1) / PAGE_SIZE;
+
+ num_pages = (bytes + PAGE_SIZE - 1) / PAGE_SIZE;
- if (file && i_size_read(file->f_mapping->host) < bytes + sizeof(bitmap_super_t)) {
+ if (file && i_size_read(file->f_mapping->host) < bytes) {
printk(KERN_INFO "%s: bitmap file too short %lu < %lu\n",
bmname(bitmap),
(unsigned long) i_size_read(file->f_mapping->host),
- bytes + sizeof(bitmap_super_t));
- goto out;
+ bytes);
+ goto err;
}
ret = -ENOMEM;
bitmap->filemap = kmalloc(sizeof(struct page *) * num_pages, GFP_KERNEL);
if (!bitmap->filemap)
- goto out;
+ goto err;
- bitmap->filemap_attr = kmalloc(sizeof(long) * num_pages, GFP_KERNEL);
+ /* We need 4 bits per page, rounded up to a multiple of sizeof(unsigned long) */
+ bitmap->filemap_attr = kzalloc(
+ roundup( DIV_ROUND_UP(num_pages*4, 8), sizeof(unsigned long)),
+ GFP_KERNEL);
if (!bitmap->filemap_attr)
- goto out;
-
- memset(bitmap->filemap_attr, 0, sizeof(long) * num_pages);
+ goto err;
oldindex = ~0L;
for (i = 0; i < chunks; i++) {
int b;
- index = file_page_index(i);
- bit = file_page_offset(i);
+ index = file_page_index(bitmap, i);
+ bit = file_page_offset(bitmap, i);
if (index != oldindex) { /* this is a new page, read it in */
+ int count;
/* unmap the old page, we're done with it */
- if (oldpage != NULL)
- kunmap(oldpage);
- if (index == 0) {
+ if (index == num_pages-1)
+ count = bytes - index * PAGE_SIZE;
+ else
+ count = PAGE_SIZE;
+ if (index == 0 && bitmap->sb_page) {
/*
* if we're here then the superblock page
* contains some bits (PAGE_SIZE != sizeof sb)
*/
page = bitmap->sb_page;
offset = sizeof(bitmap_super_t);
+ if (!file)
+ read_sb_page(bitmap->mddev,
+ bitmap->mddev->bitmap_info.offset,
+ page,
+ index, count);
} else if (file) {
- page = read_page(file, index, &dummy);
+ page = read_page(file, index, bitmap, count);
offset = 0;
} else {
- page = read_sb_page(bitmap->mddev, bitmap->offset, index);
+ page = read_sb_page(bitmap->mddev,
+ bitmap->mddev->bitmap_info.offset,
+ NULL,
+ index, count);
offset = 0;
}
if (IS_ERR(page)) { /* read error */
ret = PTR_ERR(page);
- goto out;
+ goto err;
}
oldindex = index;
oldpage = page;
- kmap(page);
+
+ bitmap->filemap[bitmap->file_pages++] = page;
+ bitmap->last_page_size = count;
if (outofdate) {
/*
* if bitmap is out of date, dirty the
* whole page and write it out
*/
- memset(page_address(page) + offset, 0xff,
+ paddr = kmap_atomic(page, KM_USER0);
+ memset(paddr + offset, 0xff,
PAGE_SIZE - offset);
- ret = write_page(bitmap, page, 1);
- if (ret) {
- kunmap(page);
- /* release, page not in filemap yet */
- page_cache_release(page);
- goto out;
- }
- }
+ kunmap_atomic(paddr, KM_USER0);
+ write_page(bitmap, page, 1);
- bitmap->filemap[bitmap->file_pages++] = page;
+ ret = -EIO;
+ if (bitmap->flags & BITMAP_WRITE_ERROR)
+ goto err;
+ }
}
+ paddr = kmap_atomic(page, KM_USER0);
if (bitmap->flags & BITMAP_HOSTENDIAN)
- b = test_bit(bit, page_address(page));
+ b = test_bit(bit, paddr);
else
- b = ext2_test_bit(bit, page_address(page));
+ b = ext2_test_bit(bit, paddr);
+ kunmap_atomic(paddr, KM_USER0);
if (b) {
/* if the disk bit is set, set the memory bit */
- bitmap_set_memory_bits(bitmap, i << CHUNK_BLOCK_SHIFT(bitmap),
- ((i+1) << (CHUNK_BLOCK_SHIFT(bitmap)) >= start)
- );
+ int needed = ((sector_t)(i+1) << (CHUNK_BLOCK_SHIFT(bitmap))
+ >= start);
+ bitmap_set_memory_bits(bitmap,
+ (sector_t)i << CHUNK_BLOCK_SHIFT(bitmap),
+ needed);
bit_cnt++;
set_page_attr(bitmap, page, BITMAP_PAGE_CLEAN);
}
ret = 0;
bitmap_mask_state(bitmap, BITMAP_STALE, MASK_UNSET);
- if (page) /* unmap the last page */
- kunmap(page);
-
if (bit_cnt) { /* Kick recovery if any bits were set */
set_bit(MD_RECOVERY_NEEDED, &bitmap->mddev->recovery);
md_wakeup_thread(bitmap->mddev->thread);
}
-out:
printk(KERN_INFO "%s: bitmap initialized from disk: "
- "read %lu/%lu pages, set %lu bits, status: %d\n",
- bmname(bitmap), bitmap->file_pages, num_pages, bit_cnt, ret);
+ "read %lu/%lu pages, set %lu bits\n",
+ bmname(bitmap), bitmap->file_pages, num_pages, bit_cnt);
+ return 0;
+
+ err:
+ printk(KERN_INFO "%s: bitmap initialisation failed: %d\n",
+ bmname(bitmap), ret);
return ret;
}
/* We don't actually write all bitmap blocks here,
* just flag them as needing to be written
*/
+ int i;
- unsigned long chunks = bitmap->chunks;
- unsigned long bytes = (chunks+7)/8 + sizeof(bitmap_super_t);
- unsigned long num_pages = (bytes + PAGE_SIZE-1) / PAGE_SIZE;
- while (num_pages--)
- bitmap->filemap_attr[num_pages] |= BITMAP_PAGE_NEEDWRITE;
+ for (i=0; i < bitmap->file_pages; i++)
+ set_page_attr(bitmap, bitmap->filemap[i],
+ BITMAP_PAGE_NEEDWRITE);
}
* out to disk
*/
-int bitmap_daemon_work(struct bitmap *bitmap)
+void bitmap_daemon_work(mddev_t *mddev)
{
+ struct bitmap *bitmap;
unsigned long j;
unsigned long flags;
struct page *page = NULL, *lastpage = NULL;
- int err = 0;
int blocks;
- int attr;
+ void *paddr;
+
+ /* Use a mutex to guard daemon_work against
+ * bitmap_destroy.
+ */
+ mutex_lock(&mddev->bitmap_info.mutex);
+ bitmap = mddev->bitmap;
+ if (bitmap == NULL) {
+ mutex_unlock(&mddev->bitmap_info.mutex);
+ return;
+ }
+ if (time_before(jiffies, bitmap->daemon_lastrun
+ + bitmap->mddev->bitmap_info.daemon_sleep))
+ goto done;
- if (bitmap == NULL)
- return 0;
- if (time_before(jiffies, bitmap->daemon_lastrun + bitmap->daemon_sleep*HZ))
- return 0;
bitmap->daemon_lastrun = jiffies;
+ if (bitmap->allclean) {
+ bitmap->mddev->thread->timeout = MAX_SCHEDULE_TIMEOUT;
+ goto done;
+ }
+ bitmap->allclean = 1;
+ spin_lock_irqsave(&bitmap->lock, flags);
for (j = 0; j < bitmap->chunks; j++) {
bitmap_counter_t *bmc;
- spin_lock_irqsave(&bitmap->lock, flags);
- if (!bitmap->filemap) {
+ if (!bitmap->filemap)
/* error or shutdown */
- spin_unlock_irqrestore(&bitmap->lock, flags);
break;
- }
page = filemap_get_page(bitmap, j);
if (page != lastpage) {
/* skip this page unless it's marked as needing cleaning */
- if (!((attr=get_page_attr(bitmap, page)) & BITMAP_PAGE_CLEAN)) {
- if (attr & BITMAP_PAGE_NEEDWRITE) {
- page_cache_get(page);
+ if (!test_page_attr(bitmap, page, BITMAP_PAGE_CLEAN)) {
+ int need_write = test_page_attr(bitmap, page,
+ BITMAP_PAGE_NEEDWRITE);
+ if (need_write)
clear_page_attr(bitmap, page, BITMAP_PAGE_NEEDWRITE);
- }
+
spin_unlock_irqrestore(&bitmap->lock, flags);
- if (attr & BITMAP_PAGE_NEEDWRITE) {
- switch (write_page(bitmap, page, 0)) {
- case -EAGAIN:
- set_page_attr(bitmap, page, BITMAP_PAGE_NEEDWRITE);
- break;
- case 0:
- break;
- default:
- bitmap_file_kick(bitmap);
- }
- page_cache_release(page);
+ if (need_write) {
+ write_page(bitmap, page, 0);
+ bitmap->allclean = 0;
}
+ spin_lock_irqsave(&bitmap->lock, flags);
+ j |= (PAGE_BITS - 1);
continue;
}
/* grab the new page, sync and release the old */
- page_cache_get(page);
if (lastpage != NULL) {
- if (get_page_attr(bitmap, lastpage) & BITMAP_PAGE_NEEDWRITE) {
+ if (test_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE)) {
clear_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE);
spin_unlock_irqrestore(&bitmap->lock, flags);
- err = write_page(bitmap, lastpage, 0);
- if (err == -EAGAIN) {
- err = 0;
- set_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE);
- }
+ write_page(bitmap, lastpage, 0);
} else {
set_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE);
spin_unlock_irqrestore(&bitmap->lock, flags);
}
- kunmap(lastpage);
- page_cache_release(lastpage);
- if (err)
- bitmap_file_kick(bitmap);
} else
spin_unlock_irqrestore(&bitmap->lock, flags);
lastpage = page;
- kmap(page);
-/*
- printk("bitmap clean at page %lu\n", j);
-*/
+
+ /* We are possibly going to clear some bits, so make
+ * sure that events_cleared is up-to-date.
+ */
+ if (bitmap->need_sync &&
+ bitmap->mddev->bitmap_info.external == 0) {
+ bitmap_super_t *sb;
+ bitmap->need_sync = 0;
+ sb = kmap_atomic(bitmap->sb_page, KM_USER0);
+ sb->events_cleared =
+ cpu_to_le64(bitmap->events_cleared);
+ kunmap_atomic(sb, KM_USER0);
+ write_page(bitmap, bitmap->sb_page, 1);
+ }
spin_lock_irqsave(&bitmap->lock, flags);
- clear_page_attr(bitmap, page, BITMAP_PAGE_CLEAN);
+ if (!bitmap->need_sync)
+ clear_page_attr(bitmap, page, BITMAP_PAGE_CLEAN);
}
- bmc = bitmap_get_counter(bitmap, j << CHUNK_BLOCK_SHIFT(bitmap),
- &blocks, 0);
+ bmc = bitmap_get_counter(bitmap,
+ (sector_t)j << CHUNK_BLOCK_SHIFT(bitmap),
+ &blocks, 0);
if (bmc) {
/*
if (j < 100) printk("bitmap: j=%lu, *bmc = 0x%x\n", j, *bmc);
*/
+ if (*bmc)
+ bitmap->allclean = 0;
+
if (*bmc == 2) {
*bmc=1; /* maybe clear the bit next time */
set_page_attr(bitmap, page, BITMAP_PAGE_CLEAN);
- } else if (*bmc == 1) {
+ } else if (*bmc == 1 && !bitmap->need_sync) {
/* we can clear the bit */
*bmc = 0;
- bitmap_count_page(bitmap, j << CHUNK_BLOCK_SHIFT(bitmap),
+ bitmap_count_page(bitmap,
+ (sector_t)j << CHUNK_BLOCK_SHIFT(bitmap),
-1);
/* clear the bit */
+ paddr = kmap_atomic(page, KM_USER0);
if (bitmap->flags & BITMAP_HOSTENDIAN)
- clear_bit(file_page_offset(j), page_address(page));
+ clear_bit(file_page_offset(bitmap, j),
+ paddr);
else
- ext2_clear_bit(file_page_offset(j), page_address(page));
+ ext2_clear_bit(file_page_offset(bitmap, j),
+ paddr);
+ kunmap_atomic(paddr, KM_USER0);
}
- }
- spin_unlock_irqrestore(&bitmap->lock, flags);
+ } else
+ j |= PAGE_COUNTER_MASK;
}
+ spin_unlock_irqrestore(&bitmap->lock, flags);
/* now sync the final page */
if (lastpage != NULL) {
- kunmap(lastpage);
spin_lock_irqsave(&bitmap->lock, flags);
- if (get_page_attr(bitmap, lastpage) &BITMAP_PAGE_NEEDWRITE) {
+ if (test_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE)) {
clear_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE);
spin_unlock_irqrestore(&bitmap->lock, flags);
- err = write_page(bitmap, lastpage, 0);
- if (err == -EAGAIN) {
- set_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE);
- err = 0;
- }
+ write_page(bitmap, lastpage, 0);
} else {
set_page_attr(bitmap, lastpage, BITMAP_PAGE_NEEDWRITE);
spin_unlock_irqrestore(&bitmap->lock, flags);
}
-
- page_cache_release(lastpage);
- }
-
- return err;
-}
-
-static void daemon_exit(struct bitmap *bitmap, mdk_thread_t **daemon)
-{
- mdk_thread_t *dmn;
- unsigned long flags;
-
- /* if no one is waiting on us, we'll free the md thread struct
- * and exit, otherwise we let the waiter clean things up */
- spin_lock_irqsave(&bitmap->lock, flags);
- if ((dmn = *daemon)) { /* no one is waiting, cleanup and exit */
- *daemon = NULL;
- spin_unlock_irqrestore(&bitmap->lock, flags);
- kfree(dmn);
- complete_and_exit(NULL, 0); /* do_exit not exported */
- }
- spin_unlock_irqrestore(&bitmap->lock, flags);
-}
-
-static void bitmap_writeback_daemon(mddev_t *mddev)
-{
- struct bitmap *bitmap = mddev->bitmap;
- struct page *page;
- struct page_list *item;
- int err = 0;
-
- if (signal_pending(current)) {
- printk(KERN_INFO
- "%s: bitmap writeback daemon got signal, exiting...\n",
- bmname(bitmap));
- err = -EINTR;
- goto out;
- }
- if (bitmap == NULL)
- /* about to be stopped. */
- return;
-
- PRINTK("%s: bitmap writeback daemon woke up...\n", bmname(bitmap));
- /* wait on bitmap page writebacks */
- while ((item = dequeue_page(bitmap))) {
- page = item->page;
- mempool_free(item, bitmap->write_pool);
- PRINTK("wait on page writeback: %p\n", page);
- wait_on_page_writeback(page);
- PRINTK("finished page writeback: %p\n", page);
-
- err = PageError(page);
- page_cache_release(page);
- if (err) {
- printk(KERN_WARNING "%s: bitmap file writeback "
- "failed (page %lu): %d\n",
- bmname(bitmap), page->index, err);
- bitmap_file_kick(bitmap);
- goto out;
- }
- }
- out:
- wake_up(&bitmap->write_wait);
- if (err) {
- printk(KERN_INFO "%s: bitmap writeback daemon exiting (%d)\n",
- bmname(bitmap), err);
- daemon_exit(bitmap, &bitmap->writeback_daemon);
- }
-}
-
-static mdk_thread_t *bitmap_start_daemon(struct bitmap *bitmap,
- void (*func)(mddev_t *), char *name)
-{
- mdk_thread_t *daemon;
- char namebuf[32];
-
-#ifdef INJECT_FATAL_FAULT_2
- daemon = NULL;
-#else
- sprintf(namebuf, "%%s_%s", name);
- daemon = md_register_thread(func, bitmap->mddev, namebuf);
-#endif
- if (!daemon) {
- printk(KERN_ERR "%s: failed to start bitmap daemon\n",
- bmname(bitmap));
- return ERR_PTR(-ECHILD);
}
- md_wakeup_thread(daemon); /* start it running */
-
- PRINTK("%s: %s daemon (pid %d) started...\n",
- bmname(bitmap), name, daemon->tsk->pid);
-
- return daemon;
-}
-
-static void bitmap_stop_daemon(struct bitmap *bitmap)
-{
- /* the daemon can't stop itself... it'll just exit instead... */
- if (bitmap->writeback_daemon && ! IS_ERR(bitmap->writeback_daemon) &&
- current->pid != bitmap->writeback_daemon->tsk->pid) {
- mdk_thread_t *daemon;
- unsigned long flags;
-
- spin_lock_irqsave(&bitmap->lock, flags);
- daemon = bitmap->writeback_daemon;
- bitmap->writeback_daemon = NULL;
- spin_unlock_irqrestore(&bitmap->lock, flags);
- if (daemon && ! IS_ERR(daemon))
- md_unregister_thread(daemon); /* destroy the thread */
- }
+ done:
+ if (bitmap->allclean == 0)
+ bitmap->mddev->thread->timeout =
+ bitmap->mddev->bitmap_info.daemon_sleep;
+ mutex_unlock(&mddev->bitmap_info.mutex);
}
static bitmap_counter_t *bitmap_get_counter(struct bitmap *bitmap,
sector_t offset, int *blocks,
int create)
+__releases(bitmap->lock)
+__acquires(bitmap->lock)
{
/* If 'create', we might release the lock and reclaim it.
* The lock must have been taken with interrupts enabled.
return 0;
}
+ if (unlikely((*bmc & COUNTER_MAX) == COUNTER_MAX)) {
+ DEFINE_WAIT(__wait);
+ /* note that it is safe to do the prepare_to_wait
+ * after the test as long as we do it before dropping
+ * the spinlock.
+ */
+ prepare_to_wait(&bitmap->overflow_wait, &__wait,
+ TASK_UNINTERRUPTIBLE);
+ spin_unlock_irq(&bitmap->lock);
+ blk_unplug(bitmap->mddev->queue);
+ schedule();
+ finish_wait(&bitmap->overflow_wait, &__wait);
+ continue;
+ }
+
switch(*bmc) {
case 0:
bitmap_file_set_bit(bitmap, offset);
bitmap_count_page(bitmap,offset, 1);
- blk_plug_device(bitmap->mddev->queue);
+ blk_plug_device_unlocked(bitmap->mddev->queue);
/* fall through */
case 1:
*bmc = 2;
}
- if ((*bmc & COUNTER_MAX) == COUNTER_MAX) BUG();
+
(*bmc)++;
spin_unlock_irq(&bitmap->lock);
sectors -= blocks;
else sectors = 0;
}
+ bitmap->allclean = 0;
return 0;
}
PRINTK(KERN_DEBUG "dec write-behind count %d/%d\n",
atomic_read(&bitmap->behind_writes), bitmap->max_write_behind);
}
+ if (bitmap->mddev->degraded)
+ /* Never clear bits or update events_cleared when degraded */
+ success = 0;
while (sectors) {
int blocks;
return;
}
+ if (success &&
+ bitmap->events_cleared < bitmap->mddev->events) {
+ bitmap->events_cleared = bitmap->mddev->events;
+ bitmap->need_sync = 1;
+ sysfs_notify_dirent(bitmap->sysfs_can_clear);
+ }
+
if (!success && ! (*bmc & NEEDED_MASK))
*bmc |= NEEDED_MASK;
+ if ((*bmc & COUNTER_MAX) == COUNTER_MAX)
+ wake_up(&bitmap->overflow_wait);
+
(*bmc)--;
if (*bmc <= 2) {
set_page_attr(bitmap,
}
}
-int bitmap_start_sync(struct bitmap *bitmap, sector_t offset, int *blocks,
- int degraded)
+static int __bitmap_start_sync(struct bitmap *bitmap, sector_t offset, int *blocks,
+ int degraded)
{
bitmap_counter_t *bmc;
int rv;
}
}
spin_unlock_irq(&bitmap->lock);
+ bitmap->allclean = 0;
+ return rv;
+}
+
+int bitmap_start_sync(struct bitmap *bitmap, sector_t offset, int *blocks,
+ int degraded)
+{
+ /* bitmap_start_sync must always report on multiples of whole
+ * pages, otherwise resync (which is very PAGE_SIZE based) will
+ * get confused.
+ * So call __bitmap_start_sync repeatedly (if needed) until
+ * At least PAGE_SIZE>>9 blocks are covered.
+ * Return the 'or' of the result.
+ */
+ int rv = 0;
+ int blocks1;
+
+ *blocks = 0;
+ while (*blocks < (PAGE_SIZE>>9)) {
+ rv |= __bitmap_start_sync(bitmap, offset,
+ &blocks1, degraded);
+ offset += blocks1;
+ *blocks += blocks1;
+ }
return rv;
}
}
unlock:
spin_unlock_irqrestore(&bitmap->lock, flags);
+ bitmap->allclean = 0;
}
void bitmap_close_sync(struct bitmap *bitmap)
*/
sector_t sector = 0;
int blocks;
- if (!bitmap) return;
+ if (!bitmap)
+ return;
while (sector < bitmap->mddev->resync_max_sectors) {
bitmap_end_sync(bitmap, sector, &blocks, 0);
-/*
- if (sector < 500) printk("bitmap_close_sync: sec %llu blks %d\n",
- (unsigned long long)sector, blocks);
-*/ sector += blocks;
+ sector += blocks;
}
}
+void bitmap_cond_end_sync(struct bitmap *bitmap, sector_t sector)
+{
+ sector_t s = 0;
+ int blocks;
+
+ if (!bitmap)
+ return;
+ if (sector == 0) {
+ bitmap->last_end_sync = jiffies;
+ return;
+ }
+ if (time_before(jiffies, (bitmap->last_end_sync
+ + bitmap->mddev->bitmap_info.daemon_sleep)))
+ return;
+ wait_event(bitmap->mddev->recovery_wait,
+ atomic_read(&bitmap->mddev->recovery_active) == 0);
+
+ bitmap->mddev->curr_resync_completed = bitmap->mddev->curr_resync;
+ set_bit(MD_CHANGE_CLEAN, &bitmap->mddev->flags);
+ sector &= ~((1ULL << CHUNK_BLOCK_SHIFT(bitmap)) - 1);
+ s = 0;
+ while (s < sector && s < bitmap->mddev->resync_max_sectors) {
+ bitmap_end_sync(bitmap, s, &blocks, 0);
+ s += blocks;
+ }
+ bitmap->last_end_sync = jiffies;
+ sysfs_notify(&bitmap->mddev->kobj, NULL, "sync_completed");
+}
+
static void bitmap_set_memory_bits(struct bitmap *bitmap, sector_t offset, int needed)
{
/* For each chunk covered by any of these sectors, set the
set_page_attr(bitmap, page, BITMAP_PAGE_CLEAN);
}
spin_unlock_irq(&bitmap->lock);
+ bitmap->allclean = 0;
+}
+/* dirty the memory and file bits for bitmap chunks "s" to "e" */
+void bitmap_dirty_bits(struct bitmap *bitmap, unsigned long s, unsigned long e)
+{
+ unsigned long chunk;
+
+ for (chunk = s; chunk <= e; chunk++) {
+ sector_t sec = (sector_t)chunk << CHUNK_BLOCK_SHIFT(bitmap);
+ bitmap_set_memory_bits(bitmap, sec, 1);
+ bitmap_file_set_bit(bitmap, sec);
+ if (sec < bitmap->mddev->recovery_cp)
+ /* We are asserting that the array is dirty,
+ * so move the recovery_cp address back so
+ * that it is obvious that it is dirty
+ */
+ bitmap->mddev->recovery_cp = sec;
+ }
}
/*
void bitmap_flush(mddev_t *mddev)
{
struct bitmap *bitmap = mddev->bitmap;
- int sleep;
+ long sleep;
if (!bitmap) /* there was no bitmap */
return;
/* run the daemon_work three time to ensure everything is flushed
* that can be
*/
- sleep = bitmap->daemon_sleep;
- bitmap->daemon_sleep = 0;
- bitmap_daemon_work(bitmap);
- bitmap_daemon_work(bitmap);
- bitmap_daemon_work(bitmap);
- bitmap->daemon_sleep = sleep;
+ sleep = mddev->bitmap_info.daemon_sleep * 2;
+ bitmap->daemon_lastrun -= sleep;
+ bitmap_daemon_work(mddev);
+ bitmap->daemon_lastrun -= sleep;
+ bitmap_daemon_work(mddev);
+ bitmap->daemon_lastrun -= sleep;
+ bitmap_daemon_work(mddev);
bitmap_update_sb(bitmap);
}
/* free all allocated memory */
- mempool_destroy(bitmap->write_pool);
-
if (bp) /* deallocate the page memory */
for (k = 0; k < pages; k++)
if (bp[k].map && !bp[k].hijacked)
kfree(bp);
kfree(bitmap);
}
+
void bitmap_destroy(mddev_t *mddev)
{
struct bitmap *bitmap = mddev->bitmap;
if (!bitmap) /* there was no bitmap */
return;
+ mutex_lock(&mddev->bitmap_info.mutex);
mddev->bitmap = NULL; /* disconnect from the md device */
+ mutex_unlock(&mddev->bitmap_info.mutex);
+ if (mddev->thread)
+ mddev->thread->timeout = MAX_SCHEDULE_TIMEOUT;
+
+ if (bitmap->sysfs_can_clear)
+ sysfs_put(bitmap->sysfs_can_clear);
bitmap_free(bitmap);
}
int bitmap_create(mddev_t *mddev)
{
struct bitmap *bitmap;
- unsigned long blocks = mddev->resync_max_sectors;
+ sector_t blocks = mddev->resync_max_sectors;
unsigned long chunks;
unsigned long pages;
- struct file *file = mddev->bitmap_file;
+ struct file *file = mddev->bitmap_info.file;
int err;
sector_t start;
+ struct sysfs_dirent *bm;
- BUG_ON(sizeof(bitmap_super_t) != 256);
+ BUILD_BUG_ON(sizeof(bitmap_super_t) != 256);
- if (!file && !mddev->bitmap_offset) /* bitmap disabled, nothing to do */
+ if (!file && !mddev->bitmap_info.offset) /* bitmap disabled, nothing to do */
return 0;
- BUG_ON(file && mddev->bitmap_offset);
+ BUG_ON(file && mddev->bitmap_info.offset);
- bitmap = kmalloc(sizeof(*bitmap), GFP_KERNEL);
+ bitmap = kzalloc(sizeof(*bitmap), GFP_KERNEL);
if (!bitmap)
return -ENOMEM;
- memset(bitmap, 0, sizeof(*bitmap));
-
spin_lock_init(&bitmap->lock);
+ atomic_set(&bitmap->pending_writes, 0);
+ init_waitqueue_head(&bitmap->write_wait);
+ init_waitqueue_head(&bitmap->overflow_wait);
+
bitmap->mddev = mddev;
- spin_lock_init(&bitmap->write_lock);
- INIT_LIST_HEAD(&bitmap->complete_pages);
- init_waitqueue_head(&bitmap->write_wait);
- bitmap->write_pool = mempool_create(WRITE_POOL_SIZE, write_pool_alloc,
- write_pool_free, NULL);
- err = -ENOMEM;
- if (!bitmap->write_pool)
- goto error;
+ bm = sysfs_get_dirent(mddev->kobj.sd, NULL, "bitmap");
+ if (bm) {
+ bitmap->sysfs_can_clear = sysfs_get_dirent(bm, NULL, "can_clear");
+ sysfs_put(bm);
+ } else
+ bitmap->sysfs_can_clear = NULL;
bitmap->file = file;
- bitmap->offset = mddev->bitmap_offset;
- if (file) get_file(file);
- /* read superblock from bitmap file (this sets bitmap->chunksize) */
- err = bitmap_read_sb(bitmap);
+ if (file) {
+ get_file(file);
+ /* As future accesses to this file will use bmap,
+ * and bypass the page cache, we must sync the file
+ * first.
+ */
+ vfs_fsync(file, 1);
+ }
+ /* read superblock from bitmap file (this sets mddev->bitmap_info.chunksize) */
+ if (!mddev->bitmap_info.external)
+ err = bitmap_read_sb(bitmap);
+ else {
+ err = 0;
+ if (mddev->bitmap_info.chunksize == 0 ||
+ mddev->bitmap_info.daemon_sleep == 0)
+ /* chunksize and time_base need to be
+ * set first. */
+ err = -EINVAL;
+ }
if (err)
goto error;
- bitmap->chunkshift = find_first_bit(&bitmap->chunksize,
- sizeof(bitmap->chunksize));
+ bitmap->daemon_lastrun = jiffies;
+ bitmap->chunkshift = ffz(~mddev->bitmap_info.chunksize);
/* now that chunksize and chunkshift are set, we can use these macros */
- chunks = (blocks + CHUNK_BLOCK_RATIO(bitmap) - 1) /
- CHUNK_BLOCK_RATIO(bitmap);
+ chunks = (blocks + CHUNK_BLOCK_RATIO(bitmap) - 1) >>
+ CHUNK_BLOCK_SHIFT(bitmap);
pages = (chunks + PAGE_COUNTER_RATIO - 1) / PAGE_COUNTER_RATIO;
BUG_ON(!pages);
#ifdef INJECT_FATAL_FAULT_1
bitmap->bp = NULL;
#else
- bitmap->bp = kmalloc(pages * sizeof(*bitmap->bp), GFP_KERNEL);
+ bitmap->bp = kzalloc(pages * sizeof(*bitmap->bp), GFP_KERNEL);
#endif
err = -ENOMEM;
if (!bitmap->bp)
goto error;
- memset(bitmap->bp, 0, pages * sizeof(*bitmap->bp));
-
- bitmap->flags |= BITMAP_ACTIVE;
/* now that we have some pages available, initialize the in-memory
* bitmap from the on-disk bitmap */
mddev->bitmap = bitmap;
- if (file)
- /* kick off the bitmap writeback daemon */
- bitmap->writeback_daemon =
- bitmap_start_daemon(bitmap,
- bitmap_writeback_daemon,
- "bitmap_wb");
+ mddev->thread->timeout = mddev->bitmap_info.daemon_sleep;
+ md_wakeup_thread(mddev->thread);
- if (IS_ERR(bitmap->writeback_daemon))
- return PTR_ERR(bitmap->writeback_daemon);
- return bitmap_update_sb(bitmap);
+ bitmap_update_sb(bitmap);
+
+ return (bitmap->flags & BITMAP_WRITE_ERROR) ? -EIO : 0;
error:
bitmap_free(bitmap);
return err;
}
+static ssize_t
+location_show(mddev_t *mddev, char *page)
+{
+ ssize_t len;
+ if (mddev->bitmap_info.file) {
+ len = sprintf(page, "file");
+ } else if (mddev->bitmap_info.offset) {
+ len = sprintf(page, "%+lld", (long long)mddev->bitmap_info.offset);
+ } else
+ len = sprintf(page, "none");
+ len += sprintf(page+len, "\n");
+ return len;
+}
+
+static ssize_t
+location_store(mddev_t *mddev, const char *buf, size_t len)
+{
+
+ if (mddev->pers) {
+ if (!mddev->pers->quiesce)
+ return -EBUSY;
+ if (mddev->recovery || mddev->sync_thread)
+ return -EBUSY;
+ }
+
+ if (mddev->bitmap || mddev->bitmap_info.file ||
+ mddev->bitmap_info.offset) {
+ /* bitmap already configured. Only option is to clear it */
+ if (strncmp(buf, "none", 4) != 0)
+ return -EBUSY;
+ if (mddev->pers) {
+ mddev->pers->quiesce(mddev, 1);
+ bitmap_destroy(mddev);
+ mddev->pers->quiesce(mddev, 0);
+ }
+ mddev->bitmap_info.offset = 0;
+ if (mddev->bitmap_info.file) {
+ struct file *f = mddev->bitmap_info.file;
+ mddev->bitmap_info.file = NULL;
+ restore_bitmap_write_access(f);
+ fput(f);
+ }
+ } else {
+ /* No bitmap, OK to set a location */
+ long long offset;
+ if (strncmp(buf, "none", 4) == 0)
+ /* nothing to be done */;
+ else if (strncmp(buf, "file:", 5) == 0) {
+ /* Not supported yet */
+ return -EINVAL;
+ } else {
+ int rv;
+ if (buf[0] == '+')
+ rv = strict_strtoll(buf+1, 10, &offset);
+ else
+ rv = strict_strtoll(buf, 10, &offset);
+ if (rv)
+ return rv;
+ if (offset == 0)
+ return -EINVAL;
+ if (mddev->bitmap_info.external == 0 &&
+ mddev->major_version == 0 &&
+ offset != mddev->bitmap_info.default_offset)
+ return -EINVAL;
+ mddev->bitmap_info.offset = offset;
+ if (mddev->pers) {
+ mddev->pers->quiesce(mddev, 1);
+ rv = bitmap_create(mddev);
+ if (rv) {
+ bitmap_destroy(mddev);
+ mddev->bitmap_info.offset = 0;
+ }
+ mddev->pers->quiesce(mddev, 0);
+ if (rv)
+ return rv;
+ }
+ }
+ }
+ if (!mddev->external) {
+ /* Ensure new bitmap info is stored in
+ * metadata promptly.
+ */
+ set_bit(MD_CHANGE_DEVS, &mddev->flags);
+ md_wakeup_thread(mddev->thread);
+ }
+ return len;
+}
+
+static struct md_sysfs_entry bitmap_location =
+__ATTR(location, S_IRUGO|S_IWUSR, location_show, location_store);
+
+static ssize_t
+timeout_show(mddev_t *mddev, char *page)
+{
+ ssize_t len;
+ unsigned long secs = mddev->bitmap_info.daemon_sleep / HZ;
+ unsigned long jifs = mddev->bitmap_info.daemon_sleep % HZ;
+
+ len = sprintf(page, "%lu", secs);
+ if (jifs)
+ len += sprintf(page+len, ".%03u", jiffies_to_msecs(jifs));
+ len += sprintf(page+len, "\n");
+ return len;
+}
+
+static ssize_t
+timeout_store(mddev_t *mddev, const char *buf, size_t len)
+{
+ /* timeout can be set at any time */
+ unsigned long timeout;
+ int rv = strict_strtoul_scaled(buf, &timeout, 4);
+ if (rv)
+ return rv;
+
+ /* just to make sure we don't overflow... */
+ if (timeout >= LONG_MAX / HZ)
+ return -EINVAL;
+
+ timeout = timeout * HZ / 10000;
+
+ if (timeout >= MAX_SCHEDULE_TIMEOUT)
+ timeout = MAX_SCHEDULE_TIMEOUT-1;
+ if (timeout < 1)
+ timeout = 1;
+ mddev->bitmap_info.daemon_sleep = timeout;
+ if (mddev->thread) {
+ /* if thread->timeout is MAX_SCHEDULE_TIMEOUT, then
+ * the bitmap is all clean and we don't need to
+ * adjust the timeout right now
+ */
+ if (mddev->thread->timeout < MAX_SCHEDULE_TIMEOUT) {
+ mddev->thread->timeout = timeout;
+ md_wakeup_thread(mddev->thread);
+ }
+ }
+ return len;
+}
+
+static struct md_sysfs_entry bitmap_timeout =
+__ATTR(time_base, S_IRUGO|S_IWUSR, timeout_show, timeout_store);
+
+static ssize_t
+backlog_show(mddev_t *mddev, char *page)
+{
+ return sprintf(page, "%lu\n", mddev->bitmap_info.max_write_behind);
+}
+
+static ssize_t
+backlog_store(mddev_t *mddev, const char *buf, size_t len)
+{
+ unsigned long backlog;
+ int rv = strict_strtoul(buf, 10, &backlog);
+ if (rv)
+ return rv;
+ if (backlog > COUNTER_MAX)
+ return -EINVAL;
+ mddev->bitmap_info.max_write_behind = backlog;
+ return len;
+}
+
+static struct md_sysfs_entry bitmap_backlog =
+__ATTR(backlog, S_IRUGO|S_IWUSR, backlog_show, backlog_store);
+
+static ssize_t
+chunksize_show(mddev_t *mddev, char *page)
+{
+ return sprintf(page, "%lu\n", mddev->bitmap_info.chunksize);
+}
+
+static ssize_t
+chunksize_store(mddev_t *mddev, const char *buf, size_t len)
+{
+ /* Can only be changed when no bitmap is active */
+ int rv;
+ unsigned long csize;
+ if (mddev->bitmap)
+ return -EBUSY;
+ rv = strict_strtoul(buf, 10, &csize);
+ if (rv)
+ return rv;
+ if (csize < 512 ||
+ !is_power_of_2(csize))
+ return -EINVAL;
+ mddev->bitmap_info.chunksize = csize;
+ return len;
+}
+
+static struct md_sysfs_entry bitmap_chunksize =
+__ATTR(chunksize, S_IRUGO|S_IWUSR, chunksize_show, chunksize_store);
+
+static ssize_t metadata_show(mddev_t *mddev, char *page)
+{
+ return sprintf(page, "%s\n", (mddev->bitmap_info.external
+ ? "external" : "internal"));
+}
+
+static ssize_t metadata_store(mddev_t *mddev, const char *buf, size_t len)
+{
+ if (mddev->bitmap ||
+ mddev->bitmap_info.file ||
+ mddev->bitmap_info.offset)
+ return -EBUSY;
+ if (strncmp(buf, "external", 8) == 0)
+ mddev->bitmap_info.external = 1;
+ else if (strncmp(buf, "internal", 8) == 0)
+ mddev->bitmap_info.external = 0;
+ else
+ return -EINVAL;
+ return len;
+}
+
+static struct md_sysfs_entry bitmap_metadata =
+__ATTR(metadata, S_IRUGO|S_IWUSR, metadata_show, metadata_store);
+
+static ssize_t can_clear_show(mddev_t *mddev, char *page)
+{
+ int len;
+ if (mddev->bitmap)
+ len = sprintf(page, "%s\n", (mddev->bitmap->need_sync ?
+ "false" : "true"));
+ else
+ len = sprintf(page, "\n");
+ return len;
+}
+
+static ssize_t can_clear_store(mddev_t *mddev, const char *buf, size_t len)
+{
+ if (mddev->bitmap == NULL)
+ return -ENOENT;
+ if (strncmp(buf, "false", 5) == 0)
+ mddev->bitmap->need_sync = 1;
+ else if (strncmp(buf, "true", 4) == 0) {
+ if (mddev->degraded)
+ return -EBUSY;
+ mddev->bitmap->need_sync = 0;
+ } else
+ return -EINVAL;
+ return len;
+}
+
+static struct md_sysfs_entry bitmap_can_clear =
+__ATTR(can_clear, S_IRUGO|S_IWUSR, can_clear_show, can_clear_store);
+
+static struct attribute *md_bitmap_attrs[] = {
+ &bitmap_location.attr,
+ &bitmap_timeout.attr,
+ &bitmap_backlog.attr,
+ &bitmap_chunksize.attr,
+ &bitmap_metadata.attr,
+ &bitmap_can_clear.attr,
+ NULL
+};
+struct attribute_group md_bitmap_group = {
+ .name = "bitmap",
+ .attrs = md_bitmap_attrs,
+};
+
+
/* the bitmap API -- for raid personalities */
EXPORT_SYMBOL(bitmap_startwrite);
EXPORT_SYMBOL(bitmap_endwrite);
EXPORT_SYMBOL(bitmap_end_sync);
EXPORT_SYMBOL(bitmap_unplug);
EXPORT_SYMBOL(bitmap_close_sync);
-EXPORT_SYMBOL(bitmap_daemon_work);
+EXPORT_SYMBOL(bitmap_cond_end_sync);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff