summaryrefslogtreecommitdiff
path: root/fs
diff options
context:
space:
mode:
authorYongqiang Yang <xiaoqiangnk@gmail.com>2011-04-04 15:40:24 -0400
committerGreg Kroah-Hartman <gregkh@suse.de>2011-04-14 13:02:40 -0700
commit6fc45e2d18e042ac3d7677fcec64e2f0308f8b5f (patch)
tree81b067bfef64830e89012d6da3765ba8efcbe5b9 /fs
parent53224a1f02f493bb1a37bad94b596cc4314777e6 (diff)
downloadlwn-6fc45e2d18e042ac3d7677fcec64e2f0308f8b5f.tar.gz
lwn-6fc45e2d18e042ac3d7677fcec64e2f0308f8b5f.zip
ext4: fix credits computing for indirect mapped files
commit 5b41395fcc0265fc9f193aef9df39ce49d64677c upstream. When writing a contiguous set of blocks, two indirect blocks could be needed depending on how the blocks are aligned, so we need to increase the number of credits needed by one. [ Also fixed a another bug which could further underestimate the number of journal credits needed by 1; the code was using integer division instead of DIV_ROUND_UP() -- tytso] Signed-off-by: Yongqiang Yang <xiaoqiangnk@gmail.com> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'fs')
-rw-r--r--fs/ext4/inode.c11
1 files changed, 5 insertions, 6 deletions
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 9f7f9e49914f..fee51dbf74dc 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -5460,13 +5460,12 @@ static int ext4_indirect_trans_blocks(struct inode *inode, int nrblocks,
/* if nrblocks are contiguous */
if (chunk) {
/*
- * With N contiguous data blocks, it need at most
- * N/EXT4_ADDR_PER_BLOCK(inode->i_sb) indirect blocks
- * 2 dindirect blocks
- * 1 tindirect block
+ * With N contiguous data blocks, we need at most
+ * N/EXT4_ADDR_PER_BLOCK(inode->i_sb) + 1 indirect blocks,
+ * 2 dindirect blocks, and 1 tindirect block
*/
- indirects = nrblocks / EXT4_ADDR_PER_BLOCK(inode->i_sb);
- return indirects + 3;
+ return DIV_ROUND_UP(nrblocks,
+ EXT4_ADDR_PER_BLOCK(inode->i_sb)) + 4;
}
/*
* if nrblocks are not contiguous, worse case, each block touch