[PATCH 40/58] [GFS2] Only fetch the dinode once in block_map

swhiteho
2008-01-21T10:16:55Z

From: Bob Peterson <rpeterso@redhat.com>

Function gfs2_block_map was often looking up the disk inode twice.
This optimizes it so that only does it once.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

diff --git a/fs/gfs2/bmap.c b/fs/gfs2/bmap.c
index 4948602..2241141 100644
--- a/fs/gfs2/bmap.c
+++ b/fs/gfs2/bmap.c
@@ -469,6 +469,7 @@ int gfs2_block_map(struct inode *inode, sector_t lblock,
unsigned int maxlen = bh_map->b_size >> inode->i_blkbits;
struct metapath mp;
u64 size;
+ struct buffer_head *dibh = NULL;

BUG_ON(maxlen == 0);

@@ -499,6 +500,8 @@ int gfs2_block_map(struct inode *inode, sector_t lblock,
error = gfs2_meta_inode_buffer(ip, &bh);
if (error)
goto out_fail;
+ dibh = bh;
+ get_bh(dibh);

for (x = 0; x < end_of_metadata; x++) {
lookup_block(ip, bh, x, &mp, create, &new, &dblock);
@@ -517,13 +520,8 @@ int gfs2_block_map(struct inode *inode, sector_t lblock,
if (boundary)
set_buffer_boundary(bh_map);
if (new) {
- struct buffer_head *dibh;
- error = gfs2_meta_inode_buffer(ip, &dibh);
- if (!error) {
- gfs2_trans_add_bh(ip->i_gl, dibh, 1);
- gfs2_dinode_out(ip, dibh->b_data);
- brelse(dibh);
- }
+ gfs2_trans_add_bh(ip->i_gl, dibh, 1);
+ gfs2_dinode_out(ip, dibh->b_data);
set_buffer_new(bh_map);
goto out_brelse;
}
@@ -544,6 +542,8 @@ out_brelse:
out_ok:
error = 0;
out_fail:
+ if (dibh)
+ brelse(dibh);
bmap_unlock(inode, create);
return error;
}
--
1.5.1.2