nilfs2: avoid readahead on metadata file for create mode
This turns off readhead action of metadata file if nilfs_mdt_get_block
function was called with a create flag.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
diff --git a/fs/nilfs2/mdt.c b/fs/nilfs2/mdt.c
index 3028e8f..948b1f8 100644
--- a/fs/nilfs2/mdt.c
+++ b/fs/nilfs2/mdt.c
@@ -186,7 +186,7 @@
}
static int nilfs_mdt_read_block(struct inode *inode, unsigned long block,
- struct buffer_head **out_bh)
+ int readahead, struct buffer_head **out_bh)
{
struct buffer_head *first_bh, *bh;
unsigned long blkoff;
@@ -200,16 +200,18 @@
if (unlikely(err))
goto failed;
- blkoff = block + 1;
- for (i = 0; i < nr_ra_blocks; i++, blkoff++) {
- err = nilfs_mdt_submit_block(inode, blkoff, READA, &bh);
- if (likely(!err || err == -EEXIST))
- brelse(bh);
- else if (err != -EBUSY)
- break; /* abort readahead if bmap lookup failed */
-
- if (!buffer_locked(first_bh))
- goto out_no_wait;
+ if (readahead) {
+ blkoff = block + 1;
+ for (i = 0; i < nr_ra_blocks; i++, blkoff++) {
+ err = nilfs_mdt_submit_block(inode, blkoff, READA, &bh);
+ if (likely(!err || err == -EEXIST))
+ brelse(bh);
+ else if (err != -EBUSY)
+ break;
+ /* abort readahead if bmap lookup failed */
+ if (!buffer_locked(first_bh))
+ goto out_no_wait;
+ }
}
wait_on_buffer(first_bh);
@@ -263,7 +265,7 @@
/* Should be rewritten with merging nilfs_mdt_read_block() */
retry:
- ret = nilfs_mdt_read_block(inode, blkoff, out_bh);
+ ret = nilfs_mdt_read_block(inode, blkoff, !create, out_bh);
if (!create || ret != -ENOENT)
return ret;
@@ -371,7 +373,7 @@
struct buffer_head *bh;
int err;
- err = nilfs_mdt_read_block(inode, block, &bh);
+ err = nilfs_mdt_read_block(inode, block, 0, &bh);
if (unlikely(err))
return err;
nilfs_mark_buffer_dirty(bh);
