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authorEvgeniy Dushistov <dushistov@mail.ru>2007-01-29 13:19:56 -0800
committerLinus Torvalds <torvalds@woody.linux-foundation.org>2007-01-30 08:26:45 -0800
commitefee2b812645d10824bf6cb247789910bcb66881 (patch)
treeb4b4c54b0064bc3b17aa778807f2f914a60848b8
parent8682164a66325cab07620082eb7f413b547f4b4a (diff)
downloadlinux-2.6.34-ux500-efee2b812645d10824bf6cb247789910bcb66881.tar.gz
[PATCH] ufs: reallocation fix
In blocks reallocation function sometimes does not update some of buffer_head::b_blocknr, which may and cause data damage. Signed-off-by: Evgeniy Dushistov <dushistov@mail.ru> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--fs/ufs/balloc.c41
1 files changed, 26 insertions, 15 deletions
diff --git a/fs/ufs/balloc.c b/fs/ufs/balloc.c
index 96ca8453bab..638f4c585e8 100644
--- a/fs/ufs/balloc.c
+++ b/fs/ufs/balloc.c
@@ -227,14 +227,14 @@ failed:
* We can come here from ufs_writepage or ufs_prepare_write,
* locked_page is argument of these functions, so we already lock it.
*/
-static void ufs_change_blocknr(struct inode *inode, unsigned int baseblk,
+static void ufs_change_blocknr(struct inode *inode, unsigned int beg,
unsigned int count, unsigned int oldb,
unsigned int newb, struct page *locked_page)
{
- unsigned int blk_per_page = 1 << (PAGE_CACHE_SHIFT - inode->i_blkbits);
- struct address_space *mapping = inode->i_mapping;
+ const unsigned mask = (1 << (PAGE_CACHE_SHIFT - inode->i_blkbits)) - 1;
+ struct address_space * const mapping = inode->i_mapping;
pgoff_t index, cur_index;
- unsigned int i, j;
+ unsigned end, pos, j;
struct page *page;
struct buffer_head *head, *bh;
@@ -246,8 +246,8 @@ static void ufs_change_blocknr(struct inode *inode, unsigned int baseblk,
cur_index = locked_page->index;
- for (i = 0; i < count; i += blk_per_page) {
- index = (baseblk+i) >> (PAGE_CACHE_SHIFT - inode->i_blkbits);
+ for (end = count + beg; beg < end; beg = (beg | mask) + 1) {
+ index = beg >> (PAGE_CACHE_SHIFT - inode->i_blkbits);
if (likely(cur_index != index)) {
page = ufs_get_locked_page(mapping, index);
@@ -256,21 +256,32 @@ static void ufs_change_blocknr(struct inode *inode, unsigned int baseblk,
} else
page = locked_page;
- j = i;
head = page_buffers(page);
bh = head;
+ pos = beg & mask;
+ for (j = 0; j < pos; ++j)
+ bh = bh->b_this_page;
+ j = 0;
do {
- if (likely(bh->b_blocknr == j + oldb && j < count)) {
- unmap_underlying_metadata(bh->b_bdev,
- bh->b_blocknr);
- bh->b_blocknr = newb + j++;
- mark_buffer_dirty(bh);
+ if (buffer_mapped(bh)) {
+ pos = bh->b_blocknr - oldb;
+ if (pos < count) {
+ UFSD(" change from %llu to %llu\n",
+ (unsigned long long)pos + oldb,
+ (unsigned long long)pos + newb);
+ bh->b_blocknr = newb + pos;
+ unmap_underlying_metadata(bh->b_bdev,
+ bh->b_blocknr);
+ mark_buffer_dirty(bh);
+ ++j;
+ }
}
bh = bh->b_this_page;
} while (bh != head);
- set_page_dirty(page);
+ if (j)
+ set_page_dirty(page);
if (likely(cur_index != index))
ufs_put_locked_page(page);
@@ -418,14 +429,14 @@ unsigned ufs_new_fragments(struct inode * inode, __fs32 * p, unsigned fragment,
}
result = ufs_alloc_fragments (inode, cgno, goal, request, err);
if (result) {
+ ufs_clear_frags(inode, result + oldcount, newcount - oldcount,
+ locked_page != NULL);
ufs_change_blocknr(inode, fragment - oldcount, oldcount, tmp,
result, locked_page);
*p = cpu_to_fs32(sb, result);
*err = 0;
UFS_I(inode)->i_lastfrag = max_t(u32, UFS_I(inode)->i_lastfrag, fragment + count);
- ufs_clear_frags(inode, result + oldcount, newcount - oldcount,
- locked_page != NULL);
unlock_super(sb);
if (newcount < request)
ufs_free_fragments (inode, result + newcount, request - newcount);