* [Ocfs2-devel] [PATCH 2/2] jbd2: return ENOSPC in journal_dirty_metadata if a handle runs out of space
2013-12-02 14:45 ` [Ocfs2-devel] [PATCH 2/2] jbd2: return ENOSPC in journal_dirty_metadata if a handle runs out of space Theodore Ts'o
@ 2013-12-02 15:35 ` Jan Kara
2013-12-03 7:34 ` Joel Becker
1 sibling, 0 replies; 3+ messages in thread
From: Jan Kara @ 2013-12-02 15:35 UTC (permalink / raw)
To: Theodore Ts'o; +Cc: Ext4 Developers List, ocfs2-devel
On Mon 02-12-13 09:45:02, Ted Tso wrote:
> If a handle runs out of space, we currently stop the kernel with a
> BUG. This makes it hard to figure out what might be going on. So
> return an error of ENOSPC, so we can let the file system layer figure
> out what is going on, to make it more likely we can get useful
> debugging information). This should make it easier to debug problems
> such as the one which was reported by:
>
> https://bugzilla.kernel.org/show_bug.cgi?id=44731
>
> The only two callers of this function are ext4_handle_dirty_metadata()
> and ocfs2_journal_dirty(). The ocfs2 function will trigger a
> BUG_ON(), which means there will be no change in behavior. The ext4
> function will call ext4_error_inode() which will print the useful
> debugging information and then handle the situation using ext4's error
> handling mechanisms (i.e., which might mean halting the kernel or
> remounting the file system read-only).
>
> Also, since both file systems already call WARN_ON(), drop the WARN_ON
> from jbd2_journal_dirty_metadata() to avoid two stack traces from
> being displayed.
>
> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
> Cc: ocfs2-devel at oss.oracle.com
The patch looks good. You can add:
Reviewed-by: Jan Kara <jack@suse.cz>
Honza
> ---
> fs/jbd2/transaction.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
> index 7aa9a32..b0b74e5 100644
> --- a/fs/jbd2/transaction.c
> +++ b/fs/jbd2/transaction.c
> @@ -1290,7 +1290,10 @@ int jbd2_journal_dirty_metadata(handle_t *handle, struct buffer_head *bh)
> * once a transaction -bzzz
> */
> jh->b_modified = 1;
> - J_ASSERT_JH(jh, handle->h_buffer_credits > 0);
> + if (handle->h_buffer_credits <= 0) {
> + ret = -ENOSPC;
> + goto out_unlock_bh;
> + }
> handle->h_buffer_credits--;
> }
>
> @@ -1373,7 +1376,6 @@ out_unlock_bh:
> jbd2_journal_put_journal_head(jh);
> out:
> JBUFFER_TRACE(jh, "exit");
> - WARN_ON(ret); /* All errors are bugs, so dump the stack */
> return ret;
> }
>
> --
> 1.8.5.rc3.362.gdf10213
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
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--
Jan Kara <jack@suse.cz>
SUSE Labs, CR
^ permalink raw reply [flat|nested] 3+ messages in thread* [Ocfs2-devel] [PATCH 2/2] jbd2: return ENOSPC in journal_dirty_metadata if a handle runs out of space
2013-12-02 14:45 ` [Ocfs2-devel] [PATCH 2/2] jbd2: return ENOSPC in journal_dirty_metadata if a handle runs out of space Theodore Ts'o
2013-12-02 15:35 ` Jan Kara
@ 2013-12-03 7:34 ` Joel Becker
1 sibling, 0 replies; 3+ messages in thread
From: Joel Becker @ 2013-12-03 7:34 UTC (permalink / raw)
To: Theodore Ts'o; +Cc: Ext4 Developers List, ocfs2-devel
On Mon, Dec 02, 2013 at 09:45:02AM -0500, Theodore Ts'o wrote:
> If a handle runs out of space, we currently stop the kernel with a
> BUG. This makes it hard to figure out what might be going on. So
> return an error of ENOSPC, so we can let the file system layer figure
> out what is going on, to make it more likely we can get useful
> debugging information). This should make it easier to debug problems
> such as the one which was reported by:
>
> https://bugzilla.kernel.org/show_bug.cgi?id=44731
>
> The only two callers of this function are ext4_handle_dirty_metadata()
> and ocfs2_journal_dirty(). The ocfs2 function will trigger a
> BUG_ON(), which means there will be no change in behavior. The ext4
> function will call ext4_error_inode() which will print the useful
> debugging information and then handle the situation using ext4's error
> handling mechanisms (i.e., which might mean halting the kernel or
> remounting the file system read-only).
>
> Also, since both file systems already call WARN_ON(), drop the WARN_ON
> from jbd2_journal_dirty_metadata() to avoid two stack traces from
> being displayed.
>
> Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
> Cc: ocfs2-devel at oss.oracle.com
Acked-by: Joel Becker <jlbec@evilplan.org>
> ---
> fs/jbd2/transaction.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)
>
> diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c
> index 7aa9a32..b0b74e5 100644
> --- a/fs/jbd2/transaction.c
> +++ b/fs/jbd2/transaction.c
> @@ -1290,7 +1290,10 @@ int jbd2_journal_dirty_metadata(handle_t *handle, struct buffer_head *bh)
> * once a transaction -bzzz
> */
> jh->b_modified = 1;
> - J_ASSERT_JH(jh, handle->h_buffer_credits > 0);
> + if (handle->h_buffer_credits <= 0) {
> + ret = -ENOSPC;
> + goto out_unlock_bh;
> + }
> handle->h_buffer_credits--;
> }
>
> @@ -1373,7 +1376,6 @@ out_unlock_bh:
> jbd2_journal_put_journal_head(jh);
> out:
> JBUFFER_TRACE(jh, "exit");
> - WARN_ON(ret); /* All errors are bugs, so dump the stack */
> return ret;
> }
>
> --
> 1.8.5.rc3.362.gdf10213
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-ext4" in
> the body of a message to majordomo at vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
--
^ permalink raw reply [flat|nested] 3+ messages in thread