xfs: simplify xfs_rmap_lookup_le call sites

Most callers of xfs_rmap_lookup_le will retrieve the btree record
immediately if the lookup succeeds.  The overlapped version of this
function (xfs_rmap_lookup_le_range) will return the record if the lookup
succeeds, so make the regular version do it too.  Get rid of the useless
len argument, since it's not part of the lookup key.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>

Author: Darrick J. Wong

fs/xfs/libxfs/xfs_rmap.c

@@ -34,18 +34,32 @@ int
 xfs_rmap_lookup_le(
 	struct xfs_btree_cur	*cur,
 	xfs_agblock_t		bno,
-	xfs_extlen_t		len,
 	uint64_t		owner,
 	uint64_t		offset,
 	unsigned int		flags,
+	struct xfs_rmap_irec	*irec,
 	int			*stat)
 {
+	int			get_stat = 0;
+	int			error;
+
 	cur->bc_rec.r.rm_startblock = bno;
-	cur->bc_rec.r.rm_blockcount = len;
+	cur->bc_rec.r.rm_blockcount = 0;
 	cur->bc_rec.r.rm_owner = owner;
 	cur->bc_rec.r.rm_offset = offset;
 	cur->bc_rec.r.rm_flags = flags;
-	return xfs_btree_lookup(cur, XFS_LOOKUP_LE, stat);
+
+	error = xfs_btree_lookup(cur, XFS_LOOKUP_LE, stat);
+	if (error || !(*stat) || !irec)
+		return error;
+
+	error = xfs_rmap_get_rec(cur, irec, &get_stat);
+	if (error)
+		return error;
+	if (!get_stat)
+		return -EFSCORRUPTED;
+
+	return 0;
 }
 
 /*
@@ -510,21 +524,14 @@ xfs_rmap_unmap(
 	 * for the AG headers at rm_startblock == 0 created by mkfs/growfs that
 	 * will not ever be removed from the tree.
 	 */
-	error = xfs_rmap_lookup_le(cur, bno, len, owner, offset, flags, &i);
+	error = xfs_rmap_lookup_le(cur, bno, owner, offset, flags, &ltrec, &i);
 	if (error)
 		goto out_error;
 	if (XFS_IS_CORRUPT(mp, i != 1)) {
 		error = -EFSCORRUPTED;
 		goto out_error;
 	}
 
-	error = xfs_rmap_get_rec(cur, &ltrec, &i);
-	if (error)
-		goto out_error;
-	if (XFS_IS_CORRUPT(mp, i != 1)) {
-		error = -EFSCORRUPTED;
-		goto out_error;
-	}
 	trace_xfs_rmap_lookup_le_range_result(cur->bc_mp,
 			cur->bc_ag.pag->pag_agno, ltrec.rm_startblock,
 			ltrec.rm_blockcount, ltrec.rm_owner,
@@ -786,18 +793,11 @@ xfs_rmap_map(
 	 * record for our insertion point. This will also give us the record for
 	 * start block contiguity tests.
 	 */
-	error = xfs_rmap_lookup_le(cur, bno, len, owner, offset, flags,
+	error = xfs_rmap_lookup_le(cur, bno, owner, offset, flags, &ltrec,
 			&have_lt);
 	if (error)
 		goto out_error;
 	if (have_lt) {
-		error = xfs_rmap_get_rec(cur, &ltrec, &have_lt);
-		if (error)
-			goto out_error;
-		if (XFS_IS_CORRUPT(mp, have_lt != 1)) {
-			error = -EFSCORRUPTED;
-			goto out_error;
-		}
 		trace_xfs_rmap_lookup_le_range_result(cur->bc_mp,
 				cur->bc_ag.pag->pag_agno, ltrec.rm_startblock,
 				ltrec.rm_blockcount, ltrec.rm_owner,
@@ -1022,21 +1022,14 @@ xfs_rmap_convert(
 	 * record for our insertion point. This will also give us the record for
 	 * start block contiguity tests.
 	 */
-	error = xfs_rmap_lookup_le(cur, bno, len, owner, offset, oldext, &i);
+	error = xfs_rmap_lookup_le(cur, bno, owner, offset, oldext, &PREV, &i);
 	if (error)
 		goto done;
 	if (XFS_IS_CORRUPT(mp, i != 1)) {
 		error = -EFSCORRUPTED;
 		goto done;
 	}
 
-	error = xfs_rmap_get_rec(cur, &PREV, &i);
-	if (error)
-		goto done;
-	if (XFS_IS_CORRUPT(mp, i != 1)) {
-		error = -EFSCORRUPTED;
-		goto done;
-	}
 	trace_xfs_rmap_lookup_le_range_result(cur->bc_mp,
 			cur->bc_ag.pag->pag_agno, PREV.rm_startblock,
 			PREV.rm_blockcount, PREV.rm_owner,
@@ -1140,7 +1133,7 @@ xfs_rmap_convert(
 			_RET_IP_);
 
 	/* reset the cursor back to PREV */
-	error = xfs_rmap_lookup_le(cur, bno, len, owner, offset, oldext, &i);
+	error = xfs_rmap_lookup_le(cur, bno, owner, offset, oldext, NULL, &i);
 	if (error)
 		goto done;
 	if (XFS_IS_CORRUPT(mp, i != 1)) {
@@ -2677,7 +2670,7 @@ xfs_rmap_record_exists(
 	ASSERT(XFS_RMAP_NON_INODE_OWNER(owner) ||
 	       (flags & XFS_RMAP_BMBT_BLOCK));
 
-	error = xfs_rmap_lookup_le(cur, bno, len, owner, offset, flags,
+	error = xfs_rmap_lookup_le(cur, bno, owner, offset, flags, &irec,
 			&has_record);
 	if (error)
 		return error;
@@ -2686,14 +2679,6 @@ xfs_rmap_record_exists(
 		return 0;
 	}
 
-	error = xfs_rmap_get_rec(cur, &irec, &has_record);
-	if (error)
-		return error;
-	if (!has_record) {
-		*has_rmap = false;
-		return 0;
-	}
-
 	*has_rmap = (irec.rm_owner == owner && irec.rm_startblock <= bno &&
 		     irec.rm_startblock + irec.rm_blockcount >= bno + len);
 	return 0;

fs/xfs/libxfs/xfs_rmap.h

@@ -122,8 +122,8 @@ int xfs_rmap_free(struct xfs_trans *tp, struct xfs_buf *agbp,
 		  const struct xfs_owner_info *oinfo);
 
 int xfs_rmap_lookup_le(struct xfs_btree_cur *cur, xfs_agblock_t bno,
-		xfs_extlen_t len, uint64_t owner, uint64_t offset,
-		unsigned int flags, int *stat);
+		uint64_t owner, uint64_t offset, unsigned int flags,
+		struct xfs_rmap_irec *irec, int *stat);
 int xfs_rmap_lookup_eq(struct xfs_btree_cur *cur, xfs_agblock_t bno,
 		xfs_extlen_t len, uint64_t owner, uint64_t offset,
 		unsigned int flags, int *stat);

fs/xfs/scrub/bmap.c

@@ -133,29 +133,13 @@ xchk_bmap_get_rmap(
 	if (info->is_shared) {
 		error = xfs_rmap_lookup_le_range(info->sc->sa.rmap_cur, agbno,
 				owner, offset, rflags, rmap, &has_rmap);
-		if (!xchk_should_check_xref(info->sc, &error,
-				&info->sc->sa.rmap_cur))
-			return false;
-		goto out;
+	} else {
+		error = xfs_rmap_lookup_le(info->sc->sa.rmap_cur, agbno,
+				owner, offset, rflags, rmap, &has_rmap);
 	}
-
-	/*
-	 * Otherwise, use the (faster) regular lookup.
-	 */
-	error = xfs_rmap_lookup_le(info->sc->sa.rmap_cur, agbno, 0, owner,
-			offset, rflags, &has_rmap);
-	if (!xchk_should_check_xref(info->sc, &error,
-			&info->sc->sa.rmap_cur))
+	if (!xchk_should_check_xref(info->sc, &error, &info->sc->sa.rmap_cur))
 		return false;
-	if (!has_rmap)
-		goto out;
 
-	error = xfs_rmap_get_rec(info->sc->sa.rmap_cur, rmap, &has_rmap);
-	if (!xchk_should_check_xref(info->sc, &error,
-			&info->sc->sa.rmap_cur))
-		return false;
-
-out:
 	if (!has_rmap)
 		xchk_fblock_xref_set_corrupt(info->sc, info->whichfork,
 			irec->br_startoff);