From patchwork Thu Jan 12 01:20:53 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [4/4] xfs: Protect xfs_file_aio_write() with sb_start_write - sb_end_write Date: Wed, 11 Jan 2012 15:20:53 -0000 From: Jan Kara X-Patchwork-Id: 135539 Message-Id: <1326331253-6497-5-git-send-email-jack@suse.cz> To: linux-fsdevel@vger.kernel.org Cc: LKML , linux-ext4@vger.kernel.org, xfs@oss.sgi.com, Eric Sandeen , Dave Chinner , Surbhi Palande , Kamal Mostafa , Christoph Hellwig , Jan Kara , Ben Myers , Alex Elder Replace racy xfs_wait_for_freeze() check with reliable sb_start_write() - sb_end_write() locking. Due to lock ranking dictated by the page fault code we have to call sb_start_write() after we acquire ilock. CC: Ben Myers CC: Alex Elder Signed-off-by: Jan Kara --- fs/xfs/xfs_file.c | 6 ++++-- 1 files changed, 4 insertions(+), 2 deletions(-) diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index 753ed9b..c5f879b 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -862,9 +862,11 @@ xfs_file_dio_aio_write( *iolock = XFS_IOLOCK_SHARED; } + sb_start_write(inode->i_sb); trace_xfs_file_direct_write(ip, count, iocb->ki_pos, 0); ret = generic_file_direct_write(iocb, iovp, &nr_segs, pos, &iocb->ki_pos, count, ocount); + sb_end_write(inode->i_sb); /* No fallback to buffered IO on errors for XFS. */ ASSERT(ret < 0 || ret == count); @@ -899,6 +901,7 @@ xfs_file_buffered_aio_write( /* We can write back this queue in page reclaim */ current->backing_dev_info = mapping->backing_dev_info; + sb_start_write(inode->i_sb); write_retry: trace_xfs_file_buffered_write(ip, count, iocb->ki_pos, 0); ret = generic_file_buffered_write(iocb, iovp, nr_segs, @@ -914,6 +917,7 @@ write_retry: enospc = 1; goto write_retry; } + sb_end_write(inode->i_sb); current->backing_dev_info = NULL; return ret; } @@ -945,8 +949,6 @@ xfs_file_aio_write( if (ocount == 0) return 0; - xfs_wait_for_freeze(ip->i_mount, SB_FREEZE_WRITE); - if (XFS_FORCED_SHUTDOWN(ip->i_mount)) return -EIO;