From e23159d2a7b2df5bce5f0ee8d57d3292243abf66 Mon Sep 17 00:00:00 2001 From: Steven Whitehouse Date: Tue, 12 Feb 2008 14:48:39 +0000 Subject: [PATCH] [GFS2] Get inode buffer only once per block map call In the case that we needed to grow the height of the metadata tree we were looking up the inode buffer and then brelse()ing it despite the fact that it is needed later in the block map process. This patch ensures that we look up the inode's buffer once and only once during the block map process. Signed-off-by: Steven Whitehouse --- fs/gfs2/bmap.c | 48 +++++++++++++++++++++--------------------------- 1 file changed, 21 insertions(+), 27 deletions(-) diff --git a/fs/gfs2/bmap.c b/fs/gfs2/bmap.c index e27e66046f0a..f1f38ca77a52 100644 --- a/fs/gfs2/bmap.c +++ b/fs/gfs2/bmap.c @@ -188,50 +188,45 @@ static int build_height(struct inode *inode, struct metapath *mp, unsigned heigh { struct gfs2_inode *ip = GFS2_I(inode); unsigned new_height = height - ip->i_height; - struct buffer_head *dibh; + struct buffer_head *dibh = mp->mp_bh[0]; struct gfs2_dinode *di; - int error; __be64 *bp; u64 bn; unsigned n, i = 0; - if (height <= ip->i_height) - return 0; - - error = gfs2_meta_inode_buffer(ip, &dibh); - if (error) - return error; + BUG_ON(height <= ip->i_height); do { n = new_height - i; bn = gfs2_alloc_block(ip, &n); gfs2_trans_add_unrevoke(GFS2_SB(inode), bn, n); do { - mp->mp_bh[i] = gfs2_meta_new(ip->i_gl, bn++); - gfs2_trans_add_bh(ip->i_gl, mp->mp_bh[i], 1); + mp->mp_bh[i + 1] = gfs2_meta_new(ip->i_gl, bn++); + gfs2_trans_add_bh(ip->i_gl, mp->mp_bh[i + 1], 1); i++; } while(i < n); } while(i < new_height); n = 0; - bn = mp->mp_bh[0]->b_blocknr; + bn = mp->mp_bh[1]->b_blocknr; if (new_height > 1) { for(; n < new_height-1; n++) { - gfs2_metatype_set(mp->mp_bh[n], GFS2_METATYPE_IN, + gfs2_metatype_set(mp->mp_bh[n + 1], GFS2_METATYPE_IN, GFS2_FORMAT_IN); - gfs2_buffer_clear_tail(mp->mp_bh[n], + gfs2_buffer_clear_tail(mp->mp_bh[n + 1], sizeof(struct gfs2_meta_header)); - bp = (__be64 *)(mp->mp_bh[n]->b_data + + bp = (__be64 *)(mp->mp_bh[n + 1]->b_data + sizeof(struct gfs2_meta_header)); - *bp = cpu_to_be64(mp->mp_bh[n+1]->b_blocknr); - brelse(mp->mp_bh[n]); - mp->mp_bh[n] = NULL; + *bp = cpu_to_be64(mp->mp_bh[n+2]->b_blocknr); + brelse(mp->mp_bh[n+1]); + mp->mp_bh[n+1] = NULL; } } - gfs2_metatype_set(mp->mp_bh[n], GFS2_METATYPE_IN, GFS2_FORMAT_IN); - gfs2_buffer_copy_tail(mp->mp_bh[n], sizeof(struct gfs2_meta_header), + gfs2_metatype_set(mp->mp_bh[n+1], GFS2_METATYPE_IN, GFS2_FORMAT_IN); + gfs2_buffer_copy_tail(mp->mp_bh[n+1], sizeof(struct gfs2_meta_header), dibh, sizeof(struct gfs2_dinode)); - brelse(mp->mp_bh[n]); + brelse(mp->mp_bh[n+1]); + mp->mp_bh[n+1] = NULL; gfs2_trans_add_bh(ip->i_gl, dibh, 1); di = (struct gfs2_dinode *)dibh->b_data; gfs2_buffer_clear_tail(dibh, sizeof(struct gfs2_dinode)); @@ -240,8 +235,7 @@ static int build_height(struct inode *inode, struct metapath *mp, unsigned heigh gfs2_add_inode_blocks(&ip->i_inode, new_height); di->di_height = cpu_to_be16(ip->i_height); di->di_blocks = cpu_to_be64(gfs2_get_inode_blocks(&ip->i_inode)); - brelse(dibh); - return error; + return 0; } /** @@ -391,11 +385,7 @@ static int lookup_metapath(struct inode *inode, struct metapath *mp, struct gfs2_inode *ip = GFS2_I(inode); unsigned int end_of_metadata = ip->i_height - 1; unsigned int x; - int ret = gfs2_meta_inode_buffer(ip, &bh); - if (ret) - return ret; - - mp->mp_bh[0] = bh; + int ret; for (x = 0; x < end_of_metadata; x++) { lookup_block(ip, x, mp, create, new, dblock); @@ -515,6 +505,10 @@ int gfs2_block_map(struct inode *inode, sector_t lblock, } size = (lblock + 1) * bsize; + error = gfs2_meta_inode_buffer(ip, &mp.mp_bh[0]); + if (error) + goto out_fail; + if (size > arr[ip->i_height]) { u8 height = ip->i_height; if (!create)