From fe033cc848489851f0c7de48f0b1bab5d744ad8a Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 30 Oct 2008 16:56:09 +1100 Subject: [XFS] implement generic xfs_btree_lookup From: Dave Chinner [hch: split out from bigger patch and minor adaptions] SGI-PV: 985583 SGI-Modid: xfs-linux-melb:xfs-kern:32192a Signed-off-by: Christoph Hellwig Signed-off-by: Lachlan McIlroy Signed-off-by: Bill O'Donnell Signed-off-by: David Chinner --- fs/xfs/xfs_bmap_btree.c | 197 +++++++----------------------------------------- 1 file changed, 29 insertions(+), 168 deletions(-) (limited to 'fs/xfs/xfs_bmap_btree.c') diff --git a/fs/xfs/xfs_bmap_btree.c b/fs/xfs/xfs_bmap_btree.c index 7b5181d34a5..8403d154ae0 100644 --- a/fs/xfs/xfs_bmap_btree.c +++ b/fs/xfs/xfs_bmap_btree.c @@ -812,146 +812,6 @@ xfs_bmbt_log_ptrs( XFS_BMBT_TRACE_CURSOR(cur, EXIT); } -/* - * Lookup the record. The cursor is made to point to it, based on dir. - */ -STATIC int /* error */ -xfs_bmbt_lookup( - xfs_btree_cur_t *cur, - xfs_lookup_t dir, - int *stat) /* success/failure */ -{ - xfs_bmbt_block_t *block=NULL; - xfs_buf_t *bp; - xfs_daddr_t d; - xfs_sfiloff_t diff; - int error; /* error return value */ - xfs_fsblock_t fsbno=0; - int high; - int i; - int keyno=0; - xfs_bmbt_key_t *kkbase=NULL; - xfs_bmbt_key_t *kkp; - xfs_bmbt_rec_t *krbase=NULL; - xfs_bmbt_rec_t *krp; - int level; - int low; - xfs_mount_t *mp; - xfs_bmbt_ptr_t *pp; - xfs_bmbt_irec_t *rp; - xfs_fileoff_t startoff; - xfs_trans_t *tp; - - XFS_STATS_INC(xs_bmbt_lookup); - XFS_BMBT_TRACE_CURSOR(cur, ENTRY); - XFS_BMBT_TRACE_ARGI(cur, (int)dir); - tp = cur->bc_tp; - mp = cur->bc_mp; - rp = &cur->bc_rec.b; - for (level = cur->bc_nlevels - 1, diff = 1; level >= 0; level--) { - if (level < cur->bc_nlevels - 1) { - d = XFS_FSB_TO_DADDR(mp, fsbno); - bp = cur->bc_bufs[level]; - if (bp && XFS_BUF_ADDR(bp) != d) - bp = NULL; - if (!bp) { - if ((error = xfs_btree_read_bufl(mp, tp, fsbno, - 0, &bp, XFS_BMAP_BTREE_REF))) { - XFS_BMBT_TRACE_CURSOR(cur, ERROR); - return error; - } - xfs_btree_setbuf(cur, level, bp); - block = XFS_BUF_TO_BMBT_BLOCK(bp); - if ((error = xfs_btree_check_lblock(cur, block, - level, bp))) { - XFS_BMBT_TRACE_CURSOR(cur, ERROR); - return error; - } - } else - block = XFS_BUF_TO_BMBT_BLOCK(bp); - } else - block = xfs_bmbt_get_block(cur, level, &bp); - if (diff == 0) - keyno = 1; - else { - if (level > 0) - kkbase = XFS_BMAP_KEY_IADDR(block, 1, cur); - else - krbase = XFS_BMAP_REC_IADDR(block, 1, cur); - low = 1; - if (!(high = be16_to_cpu(block->bb_numrecs))) { - ASSERT(level == 0); - cur->bc_ptrs[0] = dir != XFS_LOOKUP_LE; - XFS_BMBT_TRACE_CURSOR(cur, EXIT); - *stat = 0; - return 0; - } - while (low <= high) { - XFS_STATS_INC(xs_bmbt_compare); - keyno = (low + high) >> 1; - if (level > 0) { - kkp = kkbase + keyno - 1; - startoff = be64_to_cpu(kkp->br_startoff); - } else { - krp = krbase + keyno - 1; - startoff = xfs_bmbt_disk_get_startoff(krp); - } - diff = (xfs_sfiloff_t) - (startoff - rp->br_startoff); - if (diff < 0) - low = keyno + 1; - else if (diff > 0) - high = keyno - 1; - else - break; - } - } - if (level > 0) { - if (diff > 0 && --keyno < 1) - keyno = 1; - pp = XFS_BMAP_PTR_IADDR(block, keyno, cur); - fsbno = be64_to_cpu(*pp); -#ifdef DEBUG - if ((error = xfs_btree_check_lptr(cur, fsbno, level))) { - XFS_BMBT_TRACE_CURSOR(cur, ERROR); - return error; - } -#endif - cur->bc_ptrs[level] = keyno; - } - } - if (dir != XFS_LOOKUP_LE && diff < 0) { - keyno++; - /* - * If ge search and we went off the end of the block, but it's - * not the last block, we're in the wrong block. - */ - if (dir == XFS_LOOKUP_GE && keyno > be16_to_cpu(block->bb_numrecs) && - be64_to_cpu(block->bb_rightsib) != NULLDFSBNO) { - cur->bc_ptrs[0] = keyno; - if ((error = xfs_btree_increment(cur, 0, &i))) { - XFS_BMBT_TRACE_CURSOR(cur, ERROR); - return error; - } - XFS_WANT_CORRUPTED_RETURN(i == 1); - XFS_BMBT_TRACE_CURSOR(cur, EXIT); - *stat = 1; - return 0; - } - } - else if (dir == XFS_LOOKUP_LE && diff > 0) - keyno--; - cur->bc_ptrs[0] = keyno; - if (keyno == 0 || keyno > be16_to_cpu(block->bb_numrecs)) { - XFS_BMBT_TRACE_CURSOR(cur, EXIT); - *stat = 0; - } else { - XFS_BMBT_TRACE_CURSOR(cur, EXIT); - *stat = ((dir != XFS_LOOKUP_EQ) || (diff == 0)); - } - return 0; -} - /* * Move 1 record left from cur/level if possible. * Update cur to reflect the new path. @@ -1809,34 +1669,6 @@ xfs_bmbt_log_recs( XFS_BMBT_TRACE_CURSOR(cur, EXIT); } -int /* error */ -xfs_bmbt_lookup_eq( - xfs_btree_cur_t *cur, - xfs_fileoff_t off, - xfs_fsblock_t bno, - xfs_filblks_t len, - int *stat) /* success/failure */ -{ - cur->bc_rec.b.br_startoff = off; - cur->bc_rec.b.br_startblock = bno; - cur->bc_rec.b.br_blockcount = len; - return xfs_bmbt_lookup(cur, XFS_LOOKUP_EQ, stat); -} - -int /* error */ -xfs_bmbt_lookup_ge( - xfs_btree_cur_t *cur, - xfs_fileoff_t off, - xfs_fsblock_t bno, - xfs_filblks_t len, - int *stat) /* success/failure */ -{ - cur->bc_rec.b.br_startoff = off; - cur->bc_rec.b.br_startblock = bno; - cur->bc_rec.b.br_blockcount = len; - return xfs_bmbt_lookup(cur, XFS_LOOKUP_GE, stat); -} - /* * Give the bmap btree a new root block. Copy the old broot contents * down into a real block and make the broot point to it. @@ -2269,6 +2101,32 @@ xfs_bmbt_get_maxrecs( return XFS_BMAP_BLOCK_IMAXRECS(level, cur); } +STATIC void +xfs_bmbt_init_key_from_rec( + union xfs_btree_key *key, + union xfs_btree_rec *rec) +{ + key->bmbt.br_startoff = + cpu_to_be64(xfs_bmbt_disk_get_startoff(&rec->bmbt)); +} + +STATIC void +xfs_bmbt_init_ptr_from_cur( + struct xfs_btree_cur *cur, + union xfs_btree_ptr *ptr) +{ + ptr->l = 0; +} + +STATIC __int64_t +xfs_bmbt_key_diff( + struct xfs_btree_cur *cur, + union xfs_btree_key *key) +{ + return (__int64_t)be64_to_cpu(key->bmbt.br_startoff) - + cur->bc_rec.b.br_startoff; +} + #ifdef XFS_BTREE_TRACE ktrace_t *xfs_bmbt_trace_buf; @@ -2360,6 +2218,9 @@ static const struct xfs_btree_ops xfs_bmbt_ops = { .dup_cursor = xfs_bmbt_dup_cursor, .get_maxrecs = xfs_bmbt_get_maxrecs, + .init_key_from_rec = xfs_bmbt_init_key_from_rec, + .init_ptr_from_cur = xfs_bmbt_init_ptr_from_cur, + .key_diff = xfs_bmbt_key_diff, #ifdef XFS_BTREE_TRACE .trace_enter = xfs_bmbt_trace_enter, -- cgit v1.2.3-18-g5258