summaryrefslogtreecommitdiffstats
path: root/drivers/md
diff options
context:
space:
mode:
authorNeilBrown <neilb@suse.de>2012-05-22 13:55:10 +1000
committerNeilBrown <neilb@suse.de>2012-05-22 13:55:10 +1000
commit1ec885cdd01a9ad867dbb9fd32a1bfcc0875c486 (patch)
tree232eaa1e1b7820ca8e97782666f7742f78bef175 /drivers/md
parentd189122d4bca2647441fdc170dc6d4cc5c8bb2fa (diff)
downloadlinux-1ec885cdd01a9ad867dbb9fd32a1bfcc0875c486.tar.bz2
md/bitmap: move some fields of 'struct bitmap' into a 'storage' substruct.
This new 'struct bitmap_storage' reflects the external storage of the bitmap. Having this clearly defined will make it easier to change the storage used while the array is active. Signed-off-by: NeilBrown <neilb@suse.de>
Diffstat (limited to 'drivers/md')
-rw-r--r--drivers/md/bitmap.c180
-rw-r--r--drivers/md/bitmap.h17
-rw-r--r--drivers/md/md.c9
3 files changed, 110 insertions, 96 deletions
diff --git a/drivers/md/bitmap.c b/drivers/md/bitmap.c
index 511f0ed5a5db..c98f2fee1bd0 100644
--- a/drivers/md/bitmap.c
+++ b/drivers/md/bitmap.c
@@ -195,6 +195,7 @@ static int write_sb_page(struct bitmap *bitmap, struct page *page, int wait)
struct md_rdev *rdev = NULL;
struct block_device *bdev;
struct mddev *mddev = bitmap->mddev;
+ struct bitmap_storage *store = &bitmap->storage;
while ((rdev = next_active_rdev(rdev, mddev)) != NULL) {
int size = PAGE_SIZE;
@@ -202,8 +203,8 @@ static int write_sb_page(struct bitmap *bitmap, struct page *page, int wait)
bdev = (rdev->meta_bdev) ? rdev->meta_bdev : rdev->bdev;
- if (page->index == bitmap->file_pages-1)
- size = roundup(bitmap->last_page_size,
+ if (page->index == store->file_pages-1)
+ size = roundup(store->last_page_size,
bdev_logical_block_size(bdev));
/* Just make sure we aren't corrupting data or
* metadata
@@ -263,7 +264,7 @@ static void write_page(struct bitmap *bitmap, struct page *page, int wait)
{
struct buffer_head *bh;
- if (bitmap->file == NULL) {
+ if (bitmap->storage.file == NULL) {
switch (write_sb_page(bitmap, page, wait)) {
case -EINVAL:
bitmap->flags |= BITMAP_WRITE_ERROR;
@@ -408,9 +409,9 @@ void bitmap_update_sb(struct bitmap *bitmap)
return;
if (bitmap->mddev->bitmap_info.external)
return;
- if (!bitmap->sb_page) /* no superblock */
+ if (!bitmap->storage.sb_page) /* no superblock */
return;
- sb = kmap_atomic(bitmap->sb_page);
+ sb = kmap_atomic(bitmap->storage.sb_page);
sb->events = cpu_to_le64(bitmap->mddev->events);
if (bitmap->mddev->events < bitmap->events_cleared)
/* rocking back to read-only */
@@ -421,7 +422,7 @@ void bitmap_update_sb(struct bitmap *bitmap)
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);
- write_page(bitmap, bitmap->sb_page, 1);
+ write_page(bitmap, bitmap->storage.sb_page, 1);
}
/* print out the bitmap file superblock */
@@ -429,9 +430,9 @@ void bitmap_print_sb(struct bitmap *bitmap)
{
bitmap_super_t *sb;
- if (!bitmap || !bitmap->sb_page)
+ if (!bitmap || !bitmap->storage.sb_page)
return;
- sb = kmap_atomic(bitmap->sb_page);
+ sb = kmap_atomic(bitmap->storage.sb_page);
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));
@@ -470,15 +471,15 @@ static int bitmap_new_disk_sb(struct bitmap *bitmap)
unsigned long chunksize, daemon_sleep, write_behind;
int err = -EINVAL;
- bitmap->sb_page = alloc_page(GFP_KERNEL);
- if (IS_ERR(bitmap->sb_page)) {
- err = PTR_ERR(bitmap->sb_page);
- bitmap->sb_page = NULL;
+ bitmap->storage.sb_page = alloc_page(GFP_KERNEL);
+ if (IS_ERR(bitmap->storage.sb_page)) {
+ err = PTR_ERR(bitmap->storage.sb_page);
+ bitmap->storage.sb_page = NULL;
return err;
}
- bitmap->sb_page->index = 0;
+ bitmap->storage.sb_page->index = 0;
- sb = kmap_atomic(bitmap->sb_page);
+ sb = kmap_atomic(bitmap->storage.sb_page);
sb->magic = cpu_to_le32(BITMAP_MAGIC);
sb->version = cpu_to_le32(BITMAP_MAJOR_HI);
@@ -536,7 +537,7 @@ static int bitmap_read_sb(struct bitmap *bitmap)
int err = -EINVAL;
struct page *sb_page;
- if (!bitmap->file && !bitmap->mddev->bitmap_info.offset) {
+ if (!bitmap->storage.file && !bitmap->mddev->bitmap_info.offset) {
chunksize = 128 * 1024 * 1024;
daemon_sleep = 5 * HZ;
write_behind = 0;
@@ -548,13 +549,13 @@ static int bitmap_read_sb(struct bitmap *bitmap)
sb_page = alloc_page(GFP_KERNEL);
if (!sb_page)
return -ENOMEM;
- bitmap->sb_page = sb_page;
+ bitmap->storage.sb_page = sb_page;
- if (bitmap->file) {
- loff_t isize = i_size_read(bitmap->file->f_mapping->host);
+ if (bitmap->storage.file) {
+ loff_t isize = i_size_read(bitmap->storage.file->f_mapping->host);
int bytes = isize > PAGE_SIZE ? PAGE_SIZE : isize;
- err = read_page(bitmap->file, 0,
+ err = read_page(bitmap->storage.file, 0,
bitmap, bytes, sb_page);
} else {
err = read_sb_page(bitmap->mddev,
@@ -647,9 +648,9 @@ static int bitmap_mask_state(struct bitmap *bitmap, enum bitmap_state bits,
bitmap_super_t *sb;
int old;
- if (!bitmap->sb_page) /* can't set the state */
+ if (!bitmap->storage.sb_page) /* can't set the state */
return 0;
- sb = kmap_atomic(bitmap->sb_page);
+ sb = kmap_atomic(bitmap->storage.sb_page);
old = le32_to_cpu(sb->state) & bits;
switch (op) {
case MASK_SET:
@@ -678,17 +679,19 @@ static int bitmap_mask_state(struct bitmap *bitmap, enum bitmap_state bits,
* 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(struct bitmap *bitmap, unsigned long chunk)
+static inline unsigned long file_page_index(struct bitmap_storage *store,
+ unsigned long chunk)
{
- if (!bitmap->mddev->bitmap_info.external)
+ if (store->sb_page)
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(struct bitmap *bitmap, unsigned long chunk)
+static inline unsigned long file_page_offset(struct bitmap_storage *store,
+ unsigned long chunk)
{
- if (!bitmap->mddev->bitmap_info.external)
+ if (store->sb_page)
chunk += sizeof(bitmap_super_t) << 3;
return chunk & (PAGE_BITS - 1);
}
@@ -700,13 +703,13 @@ static inline unsigned long file_page_offset(struct bitmap *bitmap, unsigned lon
* 1 page (e.g., x86) or less than 1 page -- so the bitmap might start on page
* 0 or page 1
*/
-static inline struct page *filemap_get_page(struct bitmap *bitmap,
+static inline struct page *filemap_get_page(struct bitmap_storage *store,
unsigned long chunk)
{
- if (file_page_index(bitmap, chunk) >= bitmap->file_pages)
+ if (file_page_index(store, chunk) >= store->file_pages)
return NULL;
- return bitmap->filemap[file_page_index(bitmap, chunk)
- - file_page_index(bitmap, 0)];
+ return store->filemap[file_page_index(store, chunk)
+ - file_page_index(store, 0)];
}
static void bitmap_file_unmap(struct bitmap *bitmap)
@@ -715,16 +718,17 @@ static void bitmap_file_unmap(struct bitmap *bitmap)
unsigned long *attr;
int pages;
unsigned long flags;
+ struct bitmap_storage *store = &bitmap->storage;
spin_lock_irqsave(&bitmap->lock, flags);
- map = bitmap->filemap;
- bitmap->filemap = NULL;
- attr = bitmap->filemap_attr;
- bitmap->filemap_attr = NULL;
- pages = bitmap->file_pages;
- bitmap->file_pages = 0;
- sb_page = bitmap->sb_page;
- bitmap->sb_page = NULL;
+ map = store->filemap;
+ store->filemap = NULL;
+ attr = store->filemap_attr;
+ store->filemap_attr = NULL;
+ pages = store->file_pages;
+ store->file_pages = 0;
+ sb_page = store->sb_page;
+ store->sb_page = NULL;
spin_unlock_irqrestore(&bitmap->lock, flags);
while (pages--)
@@ -743,8 +747,8 @@ static void bitmap_file_put(struct bitmap *bitmap)
unsigned long flags;
spin_lock_irqsave(&bitmap->lock, flags);
- file = bitmap->file;
- bitmap->file = NULL;
+ file = bitmap->storage.file;
+ bitmap->storage.file = NULL;
spin_unlock_irqrestore(&bitmap->lock, flags);
if (file)
@@ -771,11 +775,11 @@ static void bitmap_file_kick(struct bitmap *bitmap)
if (bitmap_mask_state(bitmap, BITMAP_STALE, MASK_SET) == 0) {
bitmap_update_sb(bitmap);
- if (bitmap->file) {
+ if (bitmap->storage.file) {
path = kmalloc(PAGE_SIZE, GFP_KERNEL);
if (path)
- ptr = d_path(&bitmap->file->f_path, path,
- PAGE_SIZE);
+ ptr = d_path(&bitmap->storage.file->f_path,
+ path, PAGE_SIZE);
printk(KERN_ALERT
"%s: kicking failed bitmap file %s from array!\n",
@@ -803,19 +807,19 @@ enum bitmap_page_attr {
static inline void set_page_attr(struct bitmap *bitmap, int pnum,
enum bitmap_page_attr attr)
{
- __set_bit((pnum<<2) + attr, bitmap->filemap_attr);
+ __set_bit((pnum<<2) + attr, bitmap->storage.filemap_attr);
}
static inline void clear_page_attr(struct bitmap *bitmap, int pnum,
enum bitmap_page_attr attr)
{
- __clear_bit((pnum<<2) + attr, bitmap->filemap_attr);
+ __clear_bit((pnum<<2) + attr, bitmap->storage.filemap_attr);
}
static inline unsigned long test_page_attr(struct bitmap *bitmap, int pnum,
enum bitmap_page_attr attr)
{
- return test_bit((pnum<<2) + attr, bitmap->filemap_attr);
+ return test_bit((pnum<<2) + attr, bitmap->storage.filemap_attr);
}
/*
@@ -832,10 +836,10 @@ static void bitmap_file_set_bit(struct bitmap *bitmap, sector_t block)
void *kaddr;
unsigned long chunk = block >> bitmap->chunkshift;
- page = filemap_get_page(bitmap, chunk);
+ page = filemap_get_page(&bitmap->storage, chunk);
if (!page)
return;
- bit = file_page_offset(bitmap, chunk);
+ bit = file_page_offset(&bitmap->storage, chunk);
/* set the bit */
kaddr = kmap_atomic(page);
@@ -856,10 +860,10 @@ static void bitmap_file_clear_bit(struct bitmap *bitmap, sector_t block)
void *paddr;
unsigned long chunk = block >> bitmap->chunkshift;
- page = filemap_get_page(bitmap, chunk);
+ page = filemap_get_page(&bitmap->storage, chunk);
if (!page)
return;
- bit = file_page_offset(bitmap, chunk);
+ bit = file_page_offset(&bitmap->storage, chunk);
paddr = kmap_atomic(page);
if (bitmap->flags & BITMAP_HOSTENDIAN)
clear_bit(bit, paddr);
@@ -881,14 +885,14 @@ void bitmap_unplug(struct bitmap *bitmap)
int dirty, need_write;
int wait = 0;
- if (!bitmap || !bitmap->filemap)
+ if (!bitmap || !bitmap->storage.filemap)
return;
/* look at each page to see if there are any set bits that need to be
* flushed out to disk */
- for (i = 0; i < bitmap->file_pages; i++) {
+ for (i = 0; i < bitmap->storage.file_pages; i++) {
spin_lock_irqsave(&bitmap->lock, flags);
- if (!bitmap->filemap) {
+ if (!bitmap->storage.filemap) {
spin_unlock_irqrestore(&bitmap->lock, flags);
return;
}
@@ -903,10 +907,10 @@ void bitmap_unplug(struct bitmap *bitmap)
spin_unlock_irqrestore(&bitmap->lock, flags);
if (dirty || need_write)
- write_page(bitmap, bitmap->filemap[i], 0);
+ write_page(bitmap, bitmap->storage.filemap[i], 0);
}
if (wait) { /* if any writes were performed, we need to wait on them */
- if (bitmap->file)
+ if (bitmap->storage.file)
wait_event(bitmap->write_wait,
atomic_read(&bitmap->pending_writes)==0);
else
@@ -940,14 +944,15 @@ static int bitmap_init_from_disk(struct bitmap *bitmap, sector_t start)
int outofdate;
int ret = -ENOSPC;
void *paddr;
+ struct bitmap_storage *store = &bitmap->storage;
chunks = bitmap->chunks;
- file = bitmap->file;
+ file = store->file;
if (!file && !bitmap->mddev->bitmap_info.offset) {
/* No permanent bitmap - fill with '1s'. */
- bitmap->filemap = NULL;
- bitmap->file_pages = 0;
+ store->filemap = NULL;
+ store->file_pages = 0;
for (i = 0; i < chunks ; i++) {
/* if the disk bit is set, set the memory bit */
int needed = ((sector_t)(i+1) << (bitmap->chunkshift)
@@ -980,39 +985,40 @@ static int bitmap_init_from_disk(struct bitmap *bitmap, sector_t start)
ret = -ENOMEM;
- bitmap->filemap = kmalloc(sizeof(struct page *) * num_pages, GFP_KERNEL);
- if (!bitmap->filemap)
+ store->filemap = kmalloc(sizeof(struct page *)
+ * num_pages, GFP_KERNEL);
+ if (!store->filemap)
goto err;
pnum = 0;
offset = 0;
- if (bitmap->sb_page) {
- bitmap->filemap[0] = bitmap->sb_page;
+ if (store->sb_page) {
+ store->filemap[0] = store->sb_page;
pnum = 1;
offset = sizeof(bitmap_super_t);
}
for ( ; pnum < num_pages; pnum++) {
- bitmap->filemap[pnum] = alloc_page(GFP_KERNEL);
- if (!bitmap->filemap[pnum]) {
- bitmap->file_pages = pnum;
+ store->filemap[pnum] = alloc_page(GFP_KERNEL);
+ if (!store->filemap[pnum]) {
+ store->file_pages = pnum;
goto err;
}
}
- bitmap->file_pages = pnum;
+ store->file_pages = pnum;
/* We need 4 bits per page, rounded up to a multiple of sizeof(unsigned long) */
- bitmap->filemap_attr = kzalloc(
+ store->filemap_attr = kzalloc(
roundup(DIV_ROUND_UP(num_pages*4, 8), sizeof(unsigned long)),
GFP_KERNEL);
- if (!bitmap->filemap_attr)
+ if (!store->filemap_attr)
goto err;
oldindex = ~0L;
for (i = 0; i < chunks; i++) {
int b;
- index = file_page_index(bitmap, i);
- bit = file_page_offset(bitmap, i);
+ index = file_page_index(&bitmap->storage, i);
+ bit = file_page_offset(&bitmap->storage, i);
if (index != oldindex) { /* this is a new page, read it in */
int count;
/* unmap the old page, we're done with it */
@@ -1020,7 +1026,7 @@ static int bitmap_init_from_disk(struct bitmap *bitmap, sector_t start)
count = bytes - index * PAGE_SIZE;
else
count = PAGE_SIZE;
- page = bitmap->filemap[index];
+ page = store->filemap[index];
if (file)
ret = read_page(file, index, bitmap,
count, page);
@@ -1036,7 +1042,7 @@ static int bitmap_init_from_disk(struct bitmap *bitmap, sector_t start)
oldindex = index;
- bitmap->last_page_size = count;
+ store->last_page_size = count;
if (outofdate) {
/*
@@ -1074,7 +1080,8 @@ static int bitmap_init_from_disk(struct bitmap *bitmap, sector_t start)
printk(KERN_INFO "%s: bitmap initialized from disk: "
"read %lu/%lu pages, set %lu of %lu bits\n",
- bmname(bitmap), bitmap->file_pages, num_pages, bit_cnt, chunks);
+ bmname(bitmap), store->file_pages,
+ num_pages, bit_cnt, chunks);
return 0;
@@ -1091,14 +1098,14 @@ void bitmap_write_all(struct bitmap *bitmap)
*/
int i;
- if (!bitmap || !bitmap->filemap)
+ if (!bitmap || !bitmap->storage.filemap)
return;
- if (bitmap->file)
+ if (bitmap->storage.file)
/* Only one copy, so nothing needed */
return;
spin_lock_irq(&bitmap->lock);
- for (i = 0; i < bitmap->file_pages; i++)
+ for (i = 0; i < bitmap->storage.file_pages; i++)
set_page_attr(bitmap, i,
BITMAP_PAGE_NEEDWRITE);
bitmap->allclean = 0;
@@ -1165,7 +1172,7 @@ void bitmap_daemon_work(struct mddev *mddev)
* we will write it.
*/
spin_lock_irqsave(&bitmap->lock, flags);
- for (j = 0; j < bitmap->file_pages; j++)
+ for (j = 0; j < bitmap->storage.file_pages; j++)
if (test_page_attr(bitmap, j,
BITMAP_PAGE_PENDING)) {
set_page_attr(bitmap, j,
@@ -1180,8 +1187,8 @@ void bitmap_daemon_work(struct mddev *mddev)
* other changes */
bitmap_super_t *sb;
bitmap->need_sync = 0;
- if (bitmap->filemap) {
- sb = kmap_atomic(bitmap->sb_page);
+ if (bitmap->storage.filemap) {
+ sb = kmap_atomic(bitmap->storage.sb_page);
sb->events_cleared =
cpu_to_le64(bitmap->events_cleared);
kunmap_atomic(sb);
@@ -1233,7 +1240,7 @@ void bitmap_daemon_work(struct mddev *mddev)
* the first blocking holds the superblock and it has been updated.
* We mustn't write any other blocks before the superblock.
*/
- for (j = 0; j < bitmap->file_pages; j++) {
+ for (j = 0; j < bitmap->storage.file_pages; j++) {
if (test_page_attr(bitmap, j,
BITMAP_PAGE_DIRTY))
@@ -1244,9 +1251,9 @@ void bitmap_daemon_work(struct mddev *mddev)
clear_page_attr(bitmap, j,
BITMAP_PAGE_NEEDWRITE);
spin_unlock_irqrestore(&bitmap->lock, flags);
- write_page(bitmap, bitmap->filemap[j], 0);
+ write_page(bitmap, bitmap->storage.filemap[j], 0);
spin_lock_irqsave(&bitmap->lock, flags);
- if (!bitmap->filemap)
+ if (!bitmap->storage.filemap)
break;
}
}
@@ -1700,7 +1707,7 @@ int bitmap_create(struct mddev *mddev)
} else
bitmap->sysfs_can_clear = NULL;
- bitmap->file = file;
+ bitmap->storage.file = file;
if (file) {
get_file(file);
/* As future accesses to this file will use bmap,
@@ -1832,9 +1839,9 @@ void bitmap_status(struct seq_file *seq, struct bitmap *bitmap)
<< (PAGE_SHIFT - 10),
chunk_kb ? chunk_kb : bitmap->mddev->bitmap_info.chunksize,
chunk_kb ? "KB" : "B");
- if (bitmap->file) {
+ if (bitmap->storage.file) {
seq_printf(seq, ", file: ");
- seq_path(seq, &bitmap->file->f_path, " \t\n");
+ seq_path(seq, &bitmap->storage.file->f_path, " \t\n");
}
seq_printf(seq, "\n");
@@ -1958,8 +1965,9 @@ space_store(struct mddev *mddev, const char *buf, size_t len)
return -EINVAL;
if (mddev->bitmap &&
- sectors < ((mddev->bitmap->file_pages - 1) * PAGE_SIZE
- + mddev->bitmap->last_page_size + 511) >> 9)
+ sectors < ((mddev->bitmap->storage.file_pages - 1)
+ * PAGE_SIZE
+ + mddev->bitmap->storage.last_page_size + 511) >> 9)
return -EFBIG; /* Bitmap is too big for this small space */
/* could make sure it isn't too big, but that isn't really
diff --git a/drivers/md/bitmap.h b/drivers/md/bitmap.h
index 79e17983473a..162ab095b866 100644
--- a/drivers/md/bitmap.h
+++ b/drivers/md/bitmap.h
@@ -188,12 +188,17 @@ struct bitmap {
/* bitmap spinlock */
spinlock_t lock;
- struct file *file; /* backing disk file */
- struct page *sb_page; /* cached copy of the bitmap file superblock */
- struct page **filemap; /* list of cache pages for the file */
- unsigned long *filemap_attr; /* attributes associated w/ filemap pages */
- unsigned long file_pages; /* number of pages in the file */
- int last_page_size; /* bytes in the last page */
+ struct bitmap_storage {
+ struct file *file; /* backing disk file */
+ struct page *sb_page; /* cached copy of the bitmap
+ * file superblock */
+ struct page **filemap; /* list of cache pages for
+ * the file */
+ unsigned long *filemap_attr; /* attributes associated
+ * w/ filemap pages */
+ unsigned long file_pages; /* number of pages in the file*/
+ int last_page_size; /* bytes in the last page */
+ } storage;
unsigned long flags;
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 607771bb7e92..9e2336fbbd31 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -1989,7 +1989,7 @@ super_1_allow_new_offset(struct md_rdev *rdev,
bitmap = rdev->mddev->bitmap;
if (bitmap && !rdev->mddev->bitmap_info.file &&
rdev->sb_start + rdev->mddev->bitmap_info.offset +
- bitmap->file_pages * (PAGE_SIZE>>9) > new_offset)
+ bitmap->storage.file_pages * (PAGE_SIZE>>9) > new_offset)
return 0;
if (rdev->badblocks.sector + rdev->badblocks.size > new_offset)
return 0;
@@ -5649,7 +5649,7 @@ static int get_bitmap_file(struct mddev * mddev, void __user * arg)
goto out;
/* bitmap disabled, zero the first byte and copy out */
- if (!mddev->bitmap || !mddev->bitmap->file) {
+ if (!mddev->bitmap || !mddev->bitmap->storage.file) {
file->pathname[0] = '\0';
goto copy_out;
}
@@ -5658,7 +5658,8 @@ static int get_bitmap_file(struct mddev * mddev, void __user * arg)
if (!buf)
goto out;
- ptr = d_path(&mddev->bitmap->file->f_path, buf, sizeof(file->pathname));
+ ptr = d_path(&mddev->bitmap->storage.file->f_path,
+ buf, sizeof(file->pathname));
if (IS_ERR(ptr))
goto out;
@@ -6299,7 +6300,7 @@ static int update_array_info(struct mddev *mddev, mdu_array_info_t *info)
/* remove the bitmap */
if (!mddev->bitmap)
return -ENOENT;
- if (mddev->bitmap->file)
+ if (mddev->bitmap->storage.file)
return -EINVAL;
mddev->pers->quiesce(mddev, 1);
bitmap_destroy(mddev);