xfs: Introduce xfs_iext_max_nextents() helper

Source kernel commit: 9feb8f19665c8ba051c6a81aa7897149e7748e1e

xfs_iext_max_nextents() returns the maximum number of extents possible for one
of data, cow or attribute fork. This helper will be extended further in a
future commit when maximum extent counts associated with data/attribute forks
are increased.

Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Chandan Babu R <chandan.babu@oracle.com>
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>

5 files changed, 18 insertions, 13 deletions

diff --git a/libxfs/xfs_bmap.c b/libxfs/xfs_bmap.c
index e4386f04d4..3891de8e86 100644
--- a/libxfs/xfs_bmap.c
+++ b/libxfs/xfs_bmap.c
@@ -67,13 +67,12 @@ xfs_bmap_compute_maxlevels(
 	 * ATTR2 we have to assume the worst case scenario of a minimum size
 	 * available.
 	 */
-	if (whichfork == XFS_DATA_FORK) {
-		maxleafents = MAXEXTNUM;
+	maxleafents = xfs_iext_max_nextents(whichfork);
+	if (whichfork == XFS_DATA_FORK)
 		sz = XFS_BMDR_SPACE_CALC(MINDBTPTRS);
-	} else {
-		maxleafents = MAXAEXTNUM;
+	else
 		sz = XFS_BMDR_SPACE_CALC(MINABTPTRS);
-	}
+
 	maxrootrecs = xfs_bmdr_maxrecs(sz, 0);
 	minleafrecs = mp->m_bmap_dmnr[0];
 	minnoderecs = mp->m_bmap_dmnr[1];
diff --git a/libxfs/xfs_inode_buf.c b/libxfs/xfs_inode_buf.c
index 28662aa71a..12c117c902 100644
--- a/libxfs/xfs_inode_buf.c
+++ b/libxfs/xfs_inode_buf.c
@@ -334,6 +334,7 @@ xfs_dinode_verify_fork(
 	int			whichfork)
 {
 	uint32_t		di_nextents = XFS_DFORK_NEXTENTS(dip, whichfork);
+	xfs_extnum_t		max_extents;
 
 	switch (XFS_DFORK_FORMAT(dip, whichfork)) {
 	case XFS_DINODE_FMT_LOCAL:
@@ -355,12 +356,9 @@ xfs_dinode_verify_fork(
 			return __this_address;
 		break;
 	case XFS_DINODE_FMT_BTREE:
-		if (whichfork == XFS_ATTR_FORK) {
-			if (di_nextents > MAXAEXTNUM)
-				return __this_address;
-		} else if (di_nextents > MAXEXTNUM) {
+		max_extents = xfs_iext_max_nextents(whichfork);
+		if (di_nextents > max_extents)
 			return __this_address;
-		}
 		break;
 	default:
 		return __this_address;
diff --git a/libxfs/xfs_inode_fork.c b/libxfs/xfs_inode_fork.c
index d6ac13eea7..625d81733f 100644
--- a/libxfs/xfs_inode_fork.c
+++ b/libxfs/xfs_inode_fork.c
@@ -742,7 +742,7 @@ xfs_iext_count_may_overflow(
 	if (whichfork == XFS_COW_FORK)
 		return 0;
 
-	max_exts = (whichfork == XFS_ATTR_FORK) ? MAXAEXTNUM : MAXEXTNUM;
+	max_exts = xfs_iext_max_nextents(whichfork);
 
 	if (XFS_TEST_ERROR(false, ip->i_mount, XFS_ERRTAG_REDUCE_MAX_IEXTENTS))
 		max_exts = 10;
diff --git a/libxfs/xfs_inode_fork.h b/libxfs/xfs_inode_fork.h
index 3d64a3acb0..2605f7ff8f 100644
--- a/libxfs/xfs_inode_fork.h
+++ b/libxfs/xfs_inode_fork.h
@@ -133,6 +133,14 @@ static inline int8_t xfs_ifork_format(struct xfs_ifork *ifp)
 	return ifp->if_format;
 }
 
+static inline xfs_extnum_t xfs_iext_max_nextents(int whichfork)
+{
+	if (whichfork == XFS_DATA_FORK || whichfork == XFS_COW_FORK)
+		return MAXEXTNUM;
+
+	return MAXAEXTNUM;
+}
+
 struct xfs_ifork *xfs_ifork_alloc(enum xfs_dinode_fmt format,
 				xfs_extnum_t nextents);
 struct xfs_ifork *xfs_iext_state_to_fork(struct xfs_inode *ip, int state);
diff --git a/repair/dinode.c b/repair/dinode.c
index 8ea919698d..7cb80af2dc 100644
--- a/repair/dinode.c
+++ b/repair/dinode.c
@@ -1806,7 +1806,7 @@ _("bad nblocks %llu for inode %" PRIu64 ", would reset to %" PRIu64 "\n"),
 		}
 	}
 
-	if (nextents > MAXEXTNUM)  {
+	if (nextents > xfs_iext_max_nextents(XFS_DATA_FORK))  {
 		do_warn(
 _("too many data fork extents (%" PRIu64 ") in inode %" PRIu64 "\n"),
 			nextents, lino);
@@ -1829,7 +1829,7 @@ _("bad nextents %d for inode %" PRIu64 ", would reset to %" PRIu64 "\n"),
 		}
 	}
 
-	if (anextents > MAXAEXTNUM)  {
+	if (anextents > xfs_iext_max_nextents(XFS_ATTR_FORK))  {
 		do_warn(
 _("too many attr fork extents (%" PRIu64 ") in inode %" PRIu64 "\n"),
 			anextents, lino);