xfs: actually check xfs_btree_check_block return in xfs_btree_islastblock

Coverity points out that xfs_btree_islastblock doesn't check the return
value of xfs_btree_check_block.  Since the question "Does the cursor
point to the last block in this level?" only makes sense if the caller
previously performed a lookup or seek operation, the block should
already have been checked.

Therefore, check the return value in an ASSERT and turn the whole thing
into a static inline predicate.

Coverity-id: 114069
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>

diff --git a/fs/xfs/libxfs/xfs_btree.c b/fs/xfs/libxfs/xfs_btree.c
index 98843f1258b8ef9065bbb2e63ac2e300f78c6b6a..1fd4850c01810be7698eb8259fbfa2774bbefeab 100644 (file)
--- a/fs/xfs/libxfs/xfs_btree.c
+++ b/fs/xfs/libxfs/xfs_btree.c
@@ -716,25 +716,6 @@ xfs_btree_get_bufs(
        return xfs_trans_get_buf(tp, mp->m_ddev_targp, d, mp->m_bsize, 0);
 }
 
-/*
- * Check for the cursor referring to the last block at the given level.
- */
-int                                    /* 1=is last block, 0=not last block */
-xfs_btree_islastblock(
-       xfs_btree_cur_t         *cur,   /* btree cursor */
-       int                     level)  /* level to check */
-{
-       struct xfs_btree_block  *block; /* generic btree block pointer */
-       xfs_buf_t               *bp;    /* buffer containing block */
-
-       block = xfs_btree_get_block(cur, level, &bp);
-       xfs_btree_check_block(cur, block, level, bp);
-       if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
-               return block->bb_u.l.bb_rightsib == cpu_to_be64(NULLFSBLOCK);
-       else
-               return block->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK);
-}
-
 /*
  * Change the cursor to point to the first record at the given level.
  * Other levels are unaffected.

diff --git a/fs/xfs/libxfs/xfs_btree.h b/fs/xfs/libxfs/xfs_btree.h
index 6670120cd6901cfade4b2d79f6982f917d8cc016..fb9b2121c628ebc09eafdb7bf923045910113aeb 100644 (file)
--- a/fs/xfs/libxfs/xfs_btree.h
+++ b/fs/xfs/libxfs/xfs_btree.h
@@ -317,14 +317,6 @@ xfs_btree_get_bufs(
        xfs_agnumber_t          agno,   /* allocation group number */
        xfs_agblock_t           agbno); /* allocation group block number */
 
-/*
- * Check for the cursor referring to the last block at the given level.
- */
-int                                    /* 1=is last block, 0=not last block */
-xfs_btree_islastblock(
-       xfs_btree_cur_t         *cur,   /* btree cursor */
-       int                     level); /* level to check */
-
 /*
  * Compute first and last byte offsets for the fields given.
  * Interprets the offsets table, which contains struct field offsets.
@@ -524,4 +516,21 @@ int xfs_btree_has_record(struct xfs_btree_cur *cur, union xfs_btree_irec *low,
                union xfs_btree_irec *high, bool *exists);
 bool xfs_btree_has_more_records(struct xfs_btree_cur *cur);
 
+/* Does this cursor point to the last block in the given level? */
+static inline bool
+xfs_btree_islastblock(
+       xfs_btree_cur_t         *cur,
+       int                     level)
+{
+       struct xfs_btree_block  *block;
+       struct xfs_buf          *bp;
+
+       block = xfs_btree_get_block(cur, level, &bp);
+       ASSERT(block && xfs_btree_check_block(cur, block, level, bp) == 0);
+
+       if (cur->bc_flags & XFS_BTREE_LONG_PTRS)
+               return block->bb_u.l.bb_rightsib == cpu_to_be64(NULLFSBLOCK);
+       return block->bb_u.s.bb_rightsib == cpu_to_be32(NULLAGBLOCK);
+}
+
 #endif /* __XFS_BTREE_H__ */