Ocfs2 devel - Jun 2013 - [PATCH] ocfs2: need rollback when journal_access failed in ocfs2_orphan_add()

While adding a file into orphan dir in ocfs2_orphan_add(),
it calls __ocfs2_add_entry() before ocfs2_journal_access_di(). 
If ocfs2_journal_access_di() failed, the file is added into 
orphan dir, and orphan dir dinode updated, but file dinode 
has not been updated.
Accordingly, the data is not consistent between file dinode 
and orphan dir.

So, need to call ocfs2_journal_access_di() before __ocfs2_add_entry(),
and if ocfs2_journal_access_di() failed, orphan_fe and 
orphan_dir_inode->i_nlink need rollback. 

Signed-off-by: Younger Liu <younger.liu at huawei.com>
---
 fs/ocfs2/namei.c |   38 ++++++++++++++++++++++----------------
 1 file changed, 22 insertions(+), 16 deletions(-)

diff --git a/fs/ocfs2/namei.c b/fs/ocfs2/namei.c
index f53471d..f2da854 100644
--- a/fs/ocfs2/namei.c
+++ b/fs/ocfs2/namei.c
@@ -2012,6 +2012,21 @@ static int ocfs2_orphan_add(struct ocfs2_super *osb,
 		goto leave;
 	}
 
+	/*
+	 * We're going to journal the change of i_flags and i_orphaned_slot.
+	 * It's safe anyway, though some callers may duplicate the journaling.
+	 * Journaling within the func just make the logic look more
+	 * straightforward.
+	 */
+	status = ocfs2_journal_access_di(handle,
+					 INODE_CACHE(inode),
+					 fe_bh,
+					 OCFS2_JOURNAL_ACCESS_WRITE);
+	if (status < 0) {
+		mlog_errno(status);
+		goto leave;
+	}
+
 	/* we're a cluster, and nlink can change on disk from
 	 * underneath us... */
 	orphan_fe = (struct ocfs2_dinode *) orphan_dir_bh->b_data;
@@ -2026,22 +2041,7 @@ static int ocfs2_orphan_add(struct ocfs2_super *osb,
 				   orphan_dir_bh, lookup);
 	if (status < 0) {
 		mlog_errno(status);
-		goto leave;
-	}
-
-	/*
-	 * We're going to journal the change of i_flags and i_orphaned_slot.
-	 * It's safe anyway, though some callers may duplicate the journaling.
-	 * Journaling within the func just make the logic look more
-	 * straightforward.
-	 */
-	status = ocfs2_journal_access_di(handle,
-					 INODE_CACHE(inode),
-					 fe_bh,
-					 OCFS2_JOURNAL_ACCESS_WRITE);
-	if (status < 0) {
-		mlog_errno(status);
-		goto leave;
+		goto rollback;
 	}
 
 	fe->i_flags |= cpu_to_le32(OCFS2_ORPHANED_FL);
@@ -2057,6 +2057,12 @@ static int ocfs2_orphan_add(struct ocfs2_super *osb,
 	trace_ocfs2_orphan_add_end((unsigned long long)OCFS2_I(inode)->ip_blkno,
 				   osb->slot_num);
 
+rollback:
+	if (status < 0 && S_ISDIR(inode->i_mode)) {
+		ocfs2_add_links_count(orphan_fe, -1);
+		set_nlink(orphan_dir_inode, ocfs2_read_links_count(orphan_fe));
+	}
+
 leave:
 	brelse(orphan_dir_bh);
 
-- 1.7.9.7

Hey Younger,

On 06/19/2013 04:57 PM, Younger Liu wrote:
> While adding a file into orphan dir in ocfs2_orphan_add(),
> it calls __ocfs2_add_entry() before ocfs2_journal_access_di(). 
> If ocfs2_journal_access_di() failed, the file is added into 
> orphan dir, and orphan dir dinode updated, but file dinode 
> has not been updated.
> Accordingly, the data is not consistent between file dinode 
> and orphan dir.
> 
> So, need to call ocfs2_journal_access_di() before __ocfs2_add_entry(),
> and if ocfs2_journal_access_di() failed, orphan_fe and 
> orphan_dir_inode->i_nlink need rollback.
Yes, and this has been introduced by commits 3939fda4.
Please see my comments below.
> 
> Signed-off-by: Younger Liu <younger.liu at huawei.com>
> ---
>  fs/ocfs2/namei.c |   38 ++++++++++++++++++++++----------------
>  1 file changed, 22 insertions(+), 16 deletions(-)
> 
> diff --git a/fs/ocfs2/namei.c b/fs/ocfs2/namei.c
> index f53471d..f2da854 100644
> --- a/fs/ocfs2/namei.c
> +++ b/fs/ocfs2/namei.c
> @@ -2012,6 +2012,21 @@ static int ocfs2_orphan_add(struct ocfs2_super *osb,
>  		goto leave;
>  	}
>  
> +	/*
> +	 * We're going to journal the change of i_flags and i_orphaned_slot.
> +	 * It's safe anyway, though some callers may duplicate the
journaling.
> +	 * Journaling within the func just make the logic look more
> +	 * straightforward.
> +	 */
> +	status = ocfs2_journal_access_di(handle,
> +					 INODE_CACHE(inode),
> +					 fe_bh,
> +					 OCFS2_JOURNAL_ACCESS_WRITE);
> +	if (status < 0) {
> +		mlog_errno(status);
> +		goto leave;
> +	}
> +
>  	/* we're a cluster, and nlink can change on disk from
>  	 * underneath us... */
>  	orphan_fe = (struct ocfs2_dinode *) orphan_dir_bh->b_data;
> @@ -2026,22 +2041,7 @@ static int ocfs2_orphan_add(struct ocfs2_super *osb,
>  				   orphan_dir_bh, lookup);
>  	if (status < 0) {
>  		mlog_errno(status);
> -		goto leave;
> -	}
> -
> -	/*
> -	 * We're going to journal the change of i_flags and i_orphaned_slot.
> -	 * It's safe anyway, though some callers may duplicate the
journaling.
> -	 * Journaling within the func just make the logic look more
> -	 * straightforward.
> -	 */
> -	status = ocfs2_journal_access_di(handle,
> -					 INODE_CACHE(inode),
> -					 fe_bh,
> -					 OCFS2_JOURNAL_ACCESS_WRITE);
> -	if (status < 0) {
> -		mlog_errno(status);
> -		goto leave;
> +		goto rollback;
>  	}
>  
>  	fe->i_flags |= cpu_to_le32(OCFS2_ORPHANED_FL);
> @@ -2057,6 +2057,12 @@ static int ocfs2_orphan_add(struct ocfs2_super *osb,
>  	trace_ocfs2_orphan_add_end((unsigned long
long)OCFS2_I(inode)->ip_blkno,
>  				   osb->slot_num);
>  
> +rollback:
> +	if (status < 0 && S_ISDIR(inode->i_mode)) {
	              ^^^^ <-- But that might not be a directory, right? :-P
How about the following?

	if (status < 0) {
		if (S_ISDIR(inode->i_mode))
			ocfs2_add_links_count(orphan_fe, -1);
		set_nlink(orphan_dir_inode, ocfs2_read_links_count(orphan_fe));
	}
> +			ocfs2_add_links_count(orphan_fe, -1);
> +		set_nlink(orphan_dir_inode, ocfs2_read_links_count(orphan_fe));
> +	}
> +
>  leave:
>  	brelse(orphan_dir_bh);
>  
> -- 1.7.9.7 

Thanks,
-Jeff