From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cuda.sgi.com (cuda1.sgi.com [192.48.157.11]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id o3MJPYBk227393 for ; Thu, 22 Apr 2010 14:25:34 -0500 Received: from coco.kroah.org (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id B333A1057B5B for ; Thu, 22 Apr 2010 12:27:34 -0700 (PDT) Received: from coco.kroah.org (kroah.org [198.145.64.141]) by cuda.sgi.com with ESMTP id Pg7sweBIEQ8XmVrV for ; Thu, 22 Apr 2010 12:27:34 -0700 (PDT) Message-Id: <20100422190908.397864177@kvm.kroah.org> Date: Thu, 22 Apr 2010 12:07:42 -0700 From: Greg KH Subject: [011/197] xfs: I/O completion handlers must use NOFS allocations In-Reply-To: <20100422191857.GA13268@kroah.com> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, Alex Elder , akpm@linux-foundation.org, xfs@oss.sgi.com, torvalds@linux-foundation.org, Christoph Hellwig , alan@lxorguk.ukuu.org.uk 2.6.32-stable review patch. If anyone has any objections, please let us know. ------------------ From: Christoph Hellwig commit 80641dc66a2d6dfb22af4413227a92b8ab84c7bb upstream When completing I/O requests we must not allow the memory allocator to recurse into the filesystem, as we might deadlock on waiting for the I/O completion otherwise. The only thing currently allocating normal GFP_KERNEL memory is the allocation of the transaction structure for the unwritten extent conversion. Add a memflags argument to _xfs_trans_alloc to allow controlling the allocator behaviour. Signed-off-by: Christoph Hellwig Reported-by: Thomas Neumann Tested-by: Thomas Neumann Reviewed-by: Alex Elder Signed-off-by: Alex Elder Signed-off-by: Greg Kroah-Hartman --- fs/xfs/xfs_fsops.c | 2 +- fs/xfs/xfs_iomap.c | 9 ++++++++- fs/xfs/xfs_mount.c | 2 +- fs/xfs/xfs_trans.c | 7 ++++--- fs/xfs/xfs_trans.h | 2 +- 5 files changed, 15 insertions(+), 7 deletions(-) --- a/fs/xfs/xfs_fsops.c +++ b/fs/xfs/xfs_fsops.c @@ -611,7 +611,7 @@ xfs_fs_log_dummy( xfs_inode_t *ip; int error; - tp = _xfs_trans_alloc(mp, XFS_TRANS_DUMMY1); + tp = _xfs_trans_alloc(mp, XFS_TRANS_DUMMY1, KM_SLEEP); error = xfs_trans_reserve(tp, 0, XFS_ICHANGE_LOG_RES(mp), 0, 0, 0); if (error) { xfs_trans_cancel(tp, 0); --- a/fs/xfs/xfs_iomap.c +++ b/fs/xfs/xfs_iomap.c @@ -860,8 +860,15 @@ xfs_iomap_write_unwritten( * set up a transaction to convert the range of extents * from unwritten to real. Do allocations in a loop until * we have covered the range passed in. + * + * Note that we open code the transaction allocation here + * to pass KM_NOFS--we can't risk to recursing back into + * the filesystem here as we might be asked to write out + * the same inode that we complete here and might deadlock + * on the iolock. */ - tp = xfs_trans_alloc(mp, XFS_TRANS_STRAT_WRITE); + xfs_wait_for_freeze(mp, SB_FREEZE_TRANS); + tp = _xfs_trans_alloc(mp, XFS_TRANS_STRAT_WRITE, KM_NOFS); tp->t_flags |= XFS_TRANS_RESERVE; error = xfs_trans_reserve(tp, resblks, XFS_WRITE_LOG_RES(mp), 0, --- a/fs/xfs/xfs_mount.c +++ b/fs/xfs/xfs_mount.c @@ -1471,7 +1471,7 @@ xfs_log_sbcount( if (!xfs_sb_version_haslazysbcount(&mp->m_sb)) return 0; - tp = _xfs_trans_alloc(mp, XFS_TRANS_SB_COUNT); + tp = _xfs_trans_alloc(mp, XFS_TRANS_SB_COUNT, KM_SLEEP); error = xfs_trans_reserve(tp, 0, mp->m_sb.sb_sectsize + 128, 0, 0, XFS_DEFAULT_LOG_COUNT); if (error) { --- a/fs/xfs/xfs_trans.c +++ b/fs/xfs/xfs_trans.c @@ -236,19 +236,20 @@ xfs_trans_alloc( uint type) { xfs_wait_for_freeze(mp, SB_FREEZE_TRANS); - return _xfs_trans_alloc(mp, type); + return _xfs_trans_alloc(mp, type, KM_SLEEP); } xfs_trans_t * _xfs_trans_alloc( xfs_mount_t *mp, - uint type) + uint type, + uint memflags) { xfs_trans_t *tp; atomic_inc(&mp->m_active_trans); - tp = kmem_zone_zalloc(xfs_trans_zone, KM_SLEEP); + tp = kmem_zone_zalloc(xfs_trans_zone, memflags); tp->t_magic = XFS_TRANS_MAGIC; tp->t_type = type; tp->t_mountp = mp; --- a/fs/xfs/xfs_trans.h +++ b/fs/xfs/xfs_trans.h @@ -924,7 +924,7 @@ typedef struct xfs_trans { * XFS transaction mechanism exported interfaces. */ xfs_trans_t *xfs_trans_alloc(struct xfs_mount *, uint); -xfs_trans_t *_xfs_trans_alloc(struct xfs_mount *, uint); +xfs_trans_t *_xfs_trans_alloc(struct xfs_mount *, uint, uint); xfs_trans_t *xfs_trans_dup(xfs_trans_t *); int xfs_trans_reserve(xfs_trans_t *, uint, uint, uint, uint, uint); _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs