[PATCH 5.4 153/177] ext4: Fix credit estimate for final inode freeing

Greg Kroah-Hartman
2019-12-16T18:23:04Z

From: Jan Kara <jack@suse.cz>

commit 65db869c754e7c271691dd5feabf884347e694f5 upstream.

Estimate for the number of credits needed for final freeing of inode in
ext4_evict_inode() was to small. We may modify 4 blocks (inode & sb for
orphan deletion, bitmap & group descriptor for inode freeing) and not
just 3.

[ Fixed minor whitespace nit. -- TYT ]

Fixes: e50e5129f384 ("ext4: xattr-in-inode support")
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20191105164437.32602-6-jack@suse.cz
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
fs/ext4/inode.c | 13 +++++++++++--
1 file changed, 11 insertions(+), 2 deletions(-)

--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -196,7 +196,12 @@ void ext4_evict_inode(struct inode *inod
{
handle_t *handle;
int err;
- int extra_credits = 3;
+ /*
+ * Credits for final inode cleanup and freeing:
+ * sb + inode (ext4_orphan_del()), block bitmap, group descriptor
+ * (xattr block freeing), bitmap, group descriptor (inode freeing)
+ */
+ int extra_credits = 6;
struct ext4_xattr_inode_array *ea_inode_array = NULL;

trace_ext4_evict_inode(inode);
@@ -252,8 +257,12 @@ void ext4_evict_inode(struct inode *inod
if (!IS_NOQUOTA(inode))
extra_credits += EXT4_MAXQUOTAS_DEL_BLOCKS(inode->i_sb);

+ /*
+ * Block bitmap, group descriptor, and inode are accounted in both
+ * ext4_blocks_for_truncate() and extra_credits. So subtract 3.
+ */
handle = ext4_journal_start(inode, EXT4_HT_TRUNCATE,
- ext4_blocks_for_truncate(inode)+extra_credits);
+ ext4_blocks_for_truncate(inode) + extra_credits - 3);
if (IS_ERR(handle)) {
ext4_std_error(inode->i_sb, PTR_ERR(handle));
/*