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[PATCH] ufs: reallocation fix

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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>
This commit is contained in:
Evgeniy Dushistov 2007-01-29 13:19:56 -08:00 committed by Linus Torvalds
parent 8682164a66
commit efee2b8126
1 changed files with 26 additions and 15 deletions
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41
fs/ufs/balloc.c
View file

@ -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);