[PATCH 19/30] ocfs2: abstract the oversized extent list count check

[Joseph Qi <joseph.qi@linux.alibaba.com>]

Fold the l_count against ocfs2_extent_recs_per_inode() test into a
predicate.

Move the rationale for using the no-xattr maximum into the predicate,
next to the bound it explains, rather than leaving it at the call site
where the bound is no longer computed.

No functional change intended.

Signed-off-by: Joseph Qi <joseph.qi@linux.alibaba.com>
---
 fs/ocfs2/inode.c | 21 ++++++++++++++-------
 1 file changed, 14 insertions(+), 7 deletions(-)

diff --git a/fs/ocfs2/inode.c b/fs/ocfs2/inode.c
index 70fb032ce891..f68f8a26e6ab 100644
--- a/fs/ocfs2/inode.c
+++ b/fs/ocfs2/inode.c
@@ -255,6 +255,19 @@ static bool ocfs2_dinode_has_zero_extent_count(struct ocfs2_dinode *di)
 	return le16_to_cpu(di->id2.i_list.l_count) == 0;
 }
 
+static bool ocfs2_dinode_has_oversized_extent_count(struct super_block *sb,
+						    struct ocfs2_dinode *di)
+{
+	/*
+	 * The exact capacity depends on i_xattr_inline_size, another
+	 * unvalidated on-disk field. Inline xattrs only shrink the list, so
+	 * the no-xattr maximum is a safe upper bound that a valid l_count
+	 * never exceeds.
+	 */
+	return le16_to_cpu(di->id2.i_list.l_count) >
+		ocfs2_extent_recs_per_inode(sb);
+}
+
 void ocfs2_set_inode_flags(struct inode *inode)
 {
 	unsigned int flags = OCFS2_I(inode)->ip_attr;
@@ -1908,13 +1921,7 @@ int ocfs2_validate_inode_block(struct super_block *sb,
 					 (unsigned long long)bh->b_blocknr);
 			goto bail;
 		}
-		/*
-		 * The exact capacity depends on i_xattr_inline_size, another
-		 * unvalidated on-disk field. Inline xattrs only shrink the
-		 * list, so the no-xattr maximum is a safe upper bound that a
-		 * valid l_count never exceeds.
-		 */
-		if (count > ocfs2_extent_recs_per_inode(sb)) {
+		if (ocfs2_dinode_has_oversized_extent_count(sb, di)) {
 			rc = ocfs2_error(sb,
 					 "Invalid dinode %llu: extent list l_count %u exceeds max %u\n",
 					 (unsigned long long)bh->b_blocknr, count,
-- 
2.39.3