[XFS] implement generic xfs_btree_lookup
From: Dave Chinner <dgc@sgi.com>
[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 <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: Bill O'Donnell <billodo@sgi.com>
Signed-off-by: David Chinner <david@fromorbit.com>
diff --git a/fs/xfs/xfs_bmap_btree.c b/fs/xfs/xfs_bmap_btree.c
index 7b5181d..8403d15 100644
--- a/fs/xfs/xfs_bmap_btree.c
+++ b/fs/xfs/xfs_bmap_btree.c
@@ -813,146 +813,6 @@
}
/*
- * 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_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 @@
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 @@
.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,