[PATCH] 2.6.22.6 reiserfs: work around for dead loop in finish_unfinished

2007-09-16 Thread lepton 
Hi,
  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 doesn'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. (against 2.6.22.6)

Signed-off-by: Lepton Wu <[EMAIL PROTECTED]>

diff -X linux-2.6.22.6/Documentation/dontdiff -pru 
linux-2.6.22.6/fs/reiserfs/super.c linux-2.6.22.6-lepton/fs/reiserfs/super.c
--- linux-2.6.22.6/fs/reiserfs/super.c  2007-09-14 17:41:15.0 +0800
+++ linux-2.6.22.6-lepton/fs/reiserfs/super.c   2007-09-16 19:06:39.0 
+0800
@@ -144,7 +144,7 @@ static int finish_unfinished(struct supe
 {
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;
@@ -165,6 +165,8 @@ static int finish_unfinished(struct supe
set_cpu_key_k_offset(_cpu_key, ~0U);
max_cpu_key.key_length = 3;
 
+   memset(_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) {
@@ -277,8 +279,16 @@ static int finish_unfinished(struct supe
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(_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, 
+  _link_key, 
0);
+   }
}
 
iput(inode);
-
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[PATCH] 2.6.22.6 reiserfs: work around for dead loop in finish_unfinished

2007-09-16 Thread lepton 
Hi,
  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 doesn'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. (against 2.6.22.6)

Signed-off-by: Lepton Wu [EMAIL PROTECTED]

diff -X linux-2.6.22.6/Documentation/dontdiff -pru 
linux-2.6.22.6/fs/reiserfs/super.c linux-2.6.22.6-lepton/fs/reiserfs/super.c
--- linux-2.6.22.6/fs/reiserfs/super.c  2007-09-14 17:41:15.0 +0800
+++ linux-2.6.22.6-lepton/fs/reiserfs/super.c   2007-09-16 19:06:39.0 
+0800
@@ -144,7 +144,7 @@ static int finish_unfinished(struct supe
 {
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;
@@ -165,6 +165,8 @@ static int finish_unfinished(struct supe
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) {
@@ -277,8 +279,16 @@ static int finish_unfinished(struct supe
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);
-
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