From dbac6710a6dfcec7fbe7d9571c183d86a4237623 Mon Sep 17 00:00:00 2001 From: Steven Whitehouse Date: Tue, 29 Jan 2008 09:12:55 +0000 Subject: [GFS2] Introduce array of buffers to struct metapath The reason for doing this is to allow all the block mapping code to share the same array. As a result we can remove two arguments from lookup_metapath since they are now returned via the array. We also add a function to drop all refs to buffer heads when we are done with the metapath. The build_height function shares the struct metapath, but currently still frees its own buffers, and this will change in a future patch. Signed-off-by: Steven Whitehouse --- fs/gfs2/bmap.c | 97 +++++++++++++++++++++++++++++----------------------------- 1 file changed, 48 insertions(+), 49 deletions(-) (limited to 'fs/gfs2') diff --git a/fs/gfs2/bmap.c b/fs/gfs2/bmap.c index 08d1be4..2011dd2 100644 --- a/fs/gfs2/bmap.c +++ b/fs/gfs2/bmap.c @@ -33,6 +33,7 @@ * keep it small. */ struct metapath { + struct buffer_head *mp_bh[GFS2_MAX_META_HEIGHT]; __u16 mp_list[GFS2_MAX_META_HEIGHT]; }; @@ -185,12 +186,11 @@ out: * Returns: errno */ -static int build_height(struct inode *inode, unsigned height) +static int build_height(struct inode *inode, struct metapath *mp, unsigned height) { struct gfs2_inode *ip = GFS2_I(inode); unsigned new_height = height - ip->i_height; struct buffer_head *dibh; - struct buffer_head *blocks[GFS2_MAX_META_HEIGHT]; struct gfs2_dinode *di; int error; __be64 *bp; @@ -206,29 +206,29 @@ static int build_height(struct inode *inode, unsigned height) for(n = 0; n < new_height; n++) { bn = gfs2_alloc_meta(ip); - blocks[n] = gfs2_meta_new(ip->i_gl, bn); - gfs2_trans_add_bh(ip->i_gl, blocks[n], 1); + mp->mp_bh[n] = gfs2_meta_new(ip->i_gl, bn); + gfs2_trans_add_bh(ip->i_gl, mp->mp_bh[n], 1); } n = 0; - bn = blocks[0]->b_blocknr; + bn = mp->mp_bh[0]->b_blocknr; if (new_height > 1) { for(; n < new_height-1; n++) { - gfs2_metatype_set(blocks[n], GFS2_METATYPE_IN, + gfs2_metatype_set(mp->mp_bh[n], GFS2_METATYPE_IN, GFS2_FORMAT_IN); - gfs2_buffer_clear_tail(blocks[n], + gfs2_buffer_clear_tail(mp->mp_bh[n], sizeof(struct gfs2_meta_header)); - bp = (__be64 *)(blocks[n]->b_data + + bp = (__be64 *)(mp->mp_bh[n]->b_data + sizeof(struct gfs2_meta_header)); - *bp = cpu_to_be64(blocks[n+1]->b_blocknr); - brelse(blocks[n]); - blocks[n] = NULL; + *bp = cpu_to_be64(mp->mp_bh[n+1]->b_blocknr); + brelse(mp->mp_bh[n]); + mp->mp_bh[n] = NULL; } } - gfs2_metatype_set(blocks[n], GFS2_METATYPE_IN, GFS2_FORMAT_IN); - gfs2_buffer_copy_tail(blocks[n], sizeof(struct gfs2_meta_header), + 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), dibh, sizeof(struct gfs2_dinode)); - brelse(blocks[n]); + brelse(mp->mp_bh[n]); 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)); @@ -314,7 +314,6 @@ static void find_metapath(struct gfs2_inode *ip, u64 block, /** * metapointer - Return pointer to start of metadata in a buffer - * @bh: The buffer * @height: The metadata height (0 = dinode) * @mp: The metapath * @@ -323,9 +322,10 @@ static void find_metapath(struct gfs2_inode *ip, u64 block, * metadata tree. */ -static inline __be64 *metapointer(struct buffer_head *bh, int *boundary, - unsigned int height, const struct metapath *mp) +static inline __be64 *metapointer(int *boundary, unsigned int height, + const struct metapath *mp) { + struct buffer_head *bh = mp->mp_bh[height]; unsigned int head_size = (height > 0) ? sizeof(struct gfs2_meta_header) : sizeof(struct gfs2_dinode); __be64 *ptr; @@ -339,7 +339,6 @@ static inline __be64 *metapointer(struct buffer_head *bh, int *boundary, /** * lookup_block - Get the next metadata block in metadata tree * @ip: The GFS2 inode - * @bh: Buffer containing the pointers to metadata blocks * @height: The height of the tree (0 = dinode) * @mp: The metapath * @create: Non-zero if we may create a new meatdata block @@ -352,12 +351,12 @@ static inline __be64 *metapointer(struct buffer_head *bh, int *boundary, * */ -static int lookup_block(struct gfs2_inode *ip, struct buffer_head *bh, - unsigned int height, struct metapath *mp, int create, +static int lookup_block(struct gfs2_inode *ip, unsigned int height, + struct metapath *mp, int create, int *new, u64 *block) { int boundary; - __be64 *ptr = metapointer(bh, &boundary, height, mp); + __be64 *ptr = metapointer(&boundary, height, mp); if (*ptr) { *block = be64_to_cpu(*ptr); @@ -374,7 +373,7 @@ static int lookup_block(struct gfs2_inode *ip, struct buffer_head *bh, else *block = gfs2_alloc_meta(ip); - gfs2_trans_add_bh(ip->i_gl, bh, 1); + gfs2_trans_add_bh(ip->i_gl, mp->mp_bh[height], 1); *ptr = cpu_to_be64(*block); ip->i_di.di_blocks++; @@ -385,32 +384,38 @@ static int lookup_block(struct gfs2_inode *ip, struct buffer_head *bh, } static int lookup_metapath(struct inode *inode, struct metapath *mp, - int create, int *new, u64 *dblock, - struct buffer_head **dibh, struct buffer_head **bh) + int create, int *new, u64 *dblock) { + struct buffer_head *bh; 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); + int ret = gfs2_meta_inode_buffer(ip, &bh); if (ret) return ret; - *dibh = *bh; - get_bh(*dibh); + mp->mp_bh[0] = bh; for (x = 0; x < end_of_metadata; x++) { - lookup_block(ip, *bh, x, mp, create, new, dblock); - brelse(*bh); - *bh = NULL; + lookup_block(ip, x, mp, create, new, dblock); if (!dblock) return 0; - ret = gfs2_meta_indirect_buffer(ip, x+1, *dblock, *new, bh); + ret = gfs2_meta_indirect_buffer(ip, x+1, *dblock, *new, &mp->mp_bh[x+1]); if (ret) return ret; } - return lookup_block(ip, *bh, end_of_metadata, mp, create, new, dblock); + return lookup_block(ip, end_of_metadata, mp, create, new, dblock); +} + +static void release_metapath(struct metapath *mp) +{ + int i; + + for (i = 0; i < GFS2_MAX_META_HEIGHT; i++) + if (mp->mp_bh[i]) + brelse(mp->mp_bh[i]); } static inline void bmap_lock(struct inode *inode, int create) @@ -449,7 +454,6 @@ int gfs2_block_map(struct inode *inode, sector_t lblock, struct gfs2_inode *ip = GFS2_I(inode); struct gfs2_sbd *sdp = GFS2_SB(inode); unsigned int bsize = sdp->sd_sb.sb_bsize; - struct buffer_head *bh = NULL; int error = 0; int new = 0; u64 dblock = 0; @@ -457,13 +461,13 @@ 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; const u64 *arr = sdp->sd_heightsize; BUG_ON(maxlen == 0); if (gfs2_assert_warn(sdp, !gfs2_is_stuffed(ip))) return 0; + memset(mp.mp_bh, 0, sizeof(mp.mp_bh)); bmap_lock(inode, create); clear_buffer_mapped(bh_map); clear_buffer_new(bh_map); @@ -480,13 +484,13 @@ int gfs2_block_map(struct inode *inode, sector_t lblock, goto out_ok; while (size > arr[height]) height++; - error = build_height(inode, height); + error = build_height(inode, &mp, height); if (error) goto out_fail; } find_metapath(ip, lblock, &mp); - error = lookup_metapath(inode, &mp, create, &new, &dblock, &dibh, &bh); + error = lookup_metapath(inode, &mp, create, &new, &dblock); if (error < 0) goto out_fail; boundary = error; @@ -496,17 +500,15 @@ int gfs2_block_map(struct inode *inode, sector_t lblock, if (boundary) set_buffer_boundary(bh_map); if (new) { - gfs2_trans_add_bh(ip->i_gl, dibh, 1); - gfs2_dinode_out(ip, dibh->b_data); + gfs2_trans_add_bh(ip->i_gl, mp.mp_bh[0], 1); + gfs2_dinode_out(ip, mp.mp_bh[0]->b_data); set_buffer_new(bh_map); - goto out_brelse; + goto out_ok; } while(--maxlen && !buffer_boundary(bh_map)) { - unsigned int end_of_metadata = ip->i_height - 1; u64 eblock; - - mp.mp_list[end_of_metadata]++; - boundary = lookup_block(ip, bh, end_of_metadata, &mp, 0, &new, &eblock); + mp.mp_list[ip->i_height - 1]++; + boundary = lookup_block(ip, ip->i_height - 1, &mp, 0, &new, &eblock); if (eblock != ++dblock) break; bh_map->b_size += (1 << inode->i_blkbits); @@ -514,14 +516,10 @@ int gfs2_block_map(struct inode *inode, sector_t lblock, set_buffer_boundary(bh_map); } } -out_brelse: - if (bh) - brelse(bh); out_ok: error = 0; out_fail: - if (dibh) - brelse(dibh); + release_metapath(&mp); bmap_unlock(inode, create); return error; } @@ -819,10 +817,11 @@ static int do_grow(struct gfs2_inode *ip, u64 size) down_write(&ip->i_rw_mutex); if (size > arr[ip->i_height]) { + struct metapath mp; u8 height = ip->i_height; while(size > arr[height]) height++; - error = build_height(&ip->i_inode, height); + error = build_height(&ip->i_inode, &mp, height); } up_write(&ip->i_rw_mutex); if (error) -- cgit v1.1