[PATCH] ext4: deaccount delayed allocations at freeing inode in ext4_evict_inode()

From: Konstantin Khlebnikov
Date: Tue Oct 29 2019 - 03:17:34 EST


If inode->i_blocks is zero then ext4_evict_inode() skips ext4_truncate().
Delayed allocation extents are freed later in ext4_clear_inode() but this
happens when quota reference is already dropped. This leads to leak of
reserved space in quota block, which disappears after umount-mount.

This seems broken for a long time but worked somehow until recent changes
in delayed allocation.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx>
---
fs/ext4/inode.c | 9 +++++++++
1 file changed, 9 insertions(+)

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 516faa280ced..580898145e8f 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -293,6 +293,15 @@ void ext4_evict_inode(struct inode *inode)
inode->i_ino, err);
goto stop_handle;
}
+ } else if (EXT4_I(inode)->i_reserved_data_blocks) {
+ /* Deaccount reserve if inode has only delayed allocations. */
+ err = ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
+ if (err) {
+ ext4_warning(inode->i_sb,
+ "couldn't remove extents %lu (err %d)",
+ inode->i_ino, err);
+ goto stop_handle;
+ }
}

/* Remove xattr references. */