reiserfs: workaround for dead loop in finish_unfinished
There is possible dead loop in finish_unfinished function.
In most situation, the call chain iput -> ... -> reiserfs_delete_inode ->
remove_save_link will success. But for some reason such as data
corruption, reiserfs_delete_inode fails on reiserfs_do_truncate ->
search_for_position_by_key.
Then remove_save_link won't be called. We always get the same
"save_link_key" in the while loop in finish_unfinished function. The
following patch adds a check for the possible dead loop and just remove
save link when deap loop.
[akpm@linux-foundation.org: cleanups]
Signed-off-by: Lepton Wu <ytht.net@gmail.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Jeff Mahoney <jeffm@suse.com>
Cc: "Vladimir V. Saveliev" <vs@namesys.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/reiserfs/super.c b/fs/reiserfs/super.c
index edfd74f..b82897a 100644
--- a/fs/reiserfs/super.c
+++ b/fs/reiserfs/super.c
@@ -145,7 +145,7 @@
{
INITIALIZE_PATH(path);
struct cpu_key max_cpu_key, obj_key;
- struct reiserfs_key save_link_key;
+ struct reiserfs_key save_link_key, last_inode_key;
int retval = 0;
struct item_head *ih;
struct buffer_head *bh;
@@ -166,6 +166,8 @@
set_cpu_key_k_offset(&max_cpu_key, ~0U);
max_cpu_key.key_length = 3;
+ memset(&last_inode_key, 0, sizeof(last_inode_key));
+
#ifdef CONFIG_QUOTA
/* Needed for iput() to work correctly and not trash data */
if (s->s_flags & MS_ACTIVE) {
@@ -278,8 +280,18 @@
REISERFS_I(inode)->i_flags |= i_link_saved_unlink_mask;
/* not completed unlink (rmdir) found */
reiserfs_info(s, "Removing %k..", INODE_PKEY(inode));
- /* removal gets completed in iput */
- retval = 0;
+ if (memcmp(&last_inode_key, INODE_PKEY(inode),
+ sizeof(last_inode_key))){
+ last_inode_key = *INODE_PKEY(inode);
+ /* removal gets completed in iput */
+ retval = 0;
+ } else {
+ reiserfs_warning(s, "Dead loop in "
+ "finish_unfinished detected, "
+ "just remove save link\n");
+ retval = remove_save_link_only(s,
+ &save_link_key, 0);
+ }
}
iput(inode);