diff options
Diffstat (limited to 'fs/gfs2/bmap.c')
| -rw-r--r-- | fs/gfs2/bmap.c | 117 |
1 files changed, 54 insertions, 63 deletions
diff --git a/fs/gfs2/bmap.c b/fs/gfs2/bmap.c index 06e3447ea132..8240c1ff94f4 100644 --- a/fs/gfs2/bmap.c +++ b/fs/gfs2/bmap.c @@ -423,12 +423,29 @@ static int lookup_block(struct gfs2_inode *ip, struct buffer_head *bh, return 0; } +static inline void bmap_lock(struct inode *inode, int create) +{ + struct gfs2_inode *ip = GFS2_I(inode); + if (create) + down_write(&ip->i_rw_mutex); + else + down_read(&ip->i_rw_mutex); +} + +static inline void bmap_unlock(struct inode *inode, int create) +{ + struct gfs2_inode *ip = GFS2_I(inode); + if (create) + up_write(&ip->i_rw_mutex); + else + up_read(&ip->i_rw_mutex); +} + /** - * gfs2_block_pointers - Map a block from an inode to a disk block + * gfs2_block_map - Map a block from an inode to a disk block * @inode: The inode * @lblock: The logical block number - * @map_bh: The bh to be mapped - * @mp: metapath to use + * @bh_map: The bh to be mapped * * Find the block number on the current device which corresponds to an * inode's block. If the block had to be created, "new" will be set. @@ -436,8 +453,8 @@ static int lookup_block(struct gfs2_inode *ip, struct buffer_head *bh, * Returns: errno */ -static int gfs2_block_pointers(struct inode *inode, u64 lblock, int create, - struct buffer_head *bh_map, struct metapath *mp) +int gfs2_block_map(struct inode *inode, u64 lblock, int create, + struct buffer_head *bh_map) { struct gfs2_inode *ip = GFS2_I(inode); struct gfs2_sbd *sdp = GFS2_SB(inode); @@ -451,51 +468,55 @@ static int gfs2_block_pointers(struct inode *inode, u64 lblock, int create, u64 dblock = 0; int boundary; unsigned int maxlen = bh_map->b_size >> inode->i_blkbits; + struct metapath mp; + u64 size; BUG_ON(maxlen == 0); if (gfs2_assert_warn(sdp, !gfs2_is_stuffed(ip))) return 0; + bmap_lock(inode, create); + clear_buffer_mapped(bh_map); + clear_buffer_new(bh_map); + clear_buffer_boundary(bh_map); bsize = gfs2_is_dir(ip) ? sdp->sd_jbsize : sdp->sd_sb.sb_bsize; - - height = calc_tree_height(ip, (lblock + 1) * bsize); - if (ip->i_di.di_height < height) { - if (!create) - return 0; - - error = build_height(inode, height); - if (error) - return error; + size = (lblock + 1) * bsize; + + if (size > ip->i_di.di_size) { + height = calc_tree_height(ip, size); + if (ip->i_di.di_height < height) { + if (!create) + goto out_ok; + + error = build_height(inode, height); + if (error) + goto out_fail; + } } - find_metapath(ip, lblock, mp); + find_metapath(ip, lblock, &mp); end_of_metadata = ip->i_di.di_height - 1; - error = gfs2_meta_inode_buffer(ip, &bh); if (error) - return error; + goto out_fail; for (x = 0; x < end_of_metadata; x++) { - lookup_block(ip, bh, x, mp, create, &new, &dblock); + lookup_block(ip, bh, x, &mp, create, &new, &dblock); brelse(bh); if (!dblock) - return 0; + goto out_ok; error = gfs2_meta_indirect_buffer(ip, x+1, dblock, new, &bh); if (error) - return error; + goto out_fail; } - boundary = lookup_block(ip, bh, end_of_metadata, mp, create, &new, &dblock); - clear_buffer_mapped(bh_map); - clear_buffer_new(bh_map); - clear_buffer_boundary(bh_map); - + boundary = lookup_block(ip, bh, end_of_metadata, &mp, create, &new, &dblock); if (dblock) { map_bh(bh_map, inode->i_sb, dblock); if (boundary) - set_buffer_boundary(bh); + set_buffer_boundary(bh_map); if (new) { struct buffer_head *dibh; error = gfs2_meta_inode_buffer(ip, &dibh); @@ -510,8 +531,8 @@ static int gfs2_block_pointers(struct inode *inode, u64 lblock, int create, while(--maxlen && !buffer_boundary(bh_map)) { u64 eblock; - mp->mp_list[end_of_metadata]++; - boundary = lookup_block(ip, bh, end_of_metadata, mp, 0, &new, &eblock); + mp.mp_list[end_of_metadata]++; + boundary = lookup_block(ip, bh, end_of_metadata, &mp, 0, &new, &eblock); if (eblock != ++dblock) break; bh_map->b_size += (1 << inode->i_blkbits); @@ -521,43 +542,15 @@ static int gfs2_block_pointers(struct inode *inode, u64 lblock, int create, } out_brelse: brelse(bh); - return 0; -} - - -static inline void bmap_lock(struct inode *inode, int create) -{ - struct gfs2_inode *ip = GFS2_I(inode); - if (create) - down_write(&ip->i_rw_mutex); - else - down_read(&ip->i_rw_mutex); -} - -static inline void bmap_unlock(struct inode *inode, int create) -{ - struct gfs2_inode *ip = GFS2_I(inode); - if (create) - up_write(&ip->i_rw_mutex); - else - up_read(&ip->i_rw_mutex); -} - -int gfs2_block_map(struct inode *inode, u64 lblock, int create, - struct buffer_head *bh) -{ - struct metapath mp; - int ret; - - bmap_lock(inode, create); - ret = gfs2_block_pointers(inode, lblock, create, bh, &mp); +out_ok: + error = 0; +out_fail: bmap_unlock(inode, create); - return ret; + return error; } int gfs2_extent_map(struct inode *inode, u64 lblock, int *new, u64 *dblock, unsigned *extlen) { - struct metapath mp; struct buffer_head bh = { .b_state = 0, .b_blocknr = 0 }; int ret; int create = *new; @@ -567,9 +560,7 @@ int gfs2_extent_map(struct inode *inode, u64 lblock, int *new, u64 *dblock, unsi BUG_ON(!new); bh.b_size = 1 << (inode->i_blkbits + 5); - bmap_lock(inode, create); - ret = gfs2_block_pointers(inode, lblock, create, &bh, &mp); - bmap_unlock(inode, create); + ret = gfs2_block_map(inode, lblock, create, &bh); *extlen = bh.b_size >> inode->i_blkbits; *dblock = bh.b_blocknr; if (buffer_new(&bh)) |