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| author | Lachlan McIlroy <lachlan@sgi.com> | 2007-05-08 13:50:12 +1000 |
|---|---|---|
| committer | Tim Shimmin <tes@sgi.com> | 2007-05-08 13:50:12 +1000 |
| commit | 71dfd5a396d11512aa6c8ed0d35b268bc084bb9b (patch) | |
| tree | 843b46b1e42df50707c160650695e074f1e8d7f6 /fs | |
| parent | 3a02ee1828915d6540b415a160344775e2a4f918 (diff) | |
| download | linux-stable-71dfd5a396d11512aa6c8ed0d35b268bc084bb9b.tar.gz linux-stable-71dfd5a396d11512aa6c8ed0d35b268bc084bb9b.tar.bz2 linux-stable-71dfd5a396d11512aa6c8ed0d35b268bc084bb9b.zip | |
[XFS] Fix race in xfs_write() b/w dmapi callout and direct I/O checks.
In xfs_write() the iolock is dropped and reacquired in XFS_SEND_DATA()
which means that the file could change from not-cached to cached and we
need to redo the direct I/O checks. We should also redo the direct I/O
checks when the file size changes regardless if O_APPEND is set or not.
SGI-PV: 963483
SGI-Modid: xfs-linux-melb:xfs-kern:28440a
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: David Chinner <dgc@sgi.com>
Signed-off-by: Tim Shimmin <tes@sgi.com>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/xfs/linux-2.6/xfs_lrw.c | 53 |
1 files changed, 26 insertions, 27 deletions
diff --git a/fs/xfs/linux-2.6/xfs_lrw.c b/fs/xfs/linux-2.6/xfs_lrw.c index 82ab792c7fc9..b2a1beb33888 100644 --- a/fs/xfs/linux-2.6/xfs_lrw.c +++ b/fs/xfs/linux-2.6/xfs_lrw.c @@ -724,34 +724,8 @@ start: goto out_unlock_mutex; } - if (ioflags & IO_ISDIRECT) { - xfs_buftarg_t *target = - (xip->i_d.di_flags & XFS_DIFLAG_REALTIME) ? - mp->m_rtdev_targp : mp->m_ddev_targp; - - if ((pos & target->bt_smask) || (count & target->bt_smask)) { - xfs_iunlock(xip, XFS_ILOCK_EXCL|iolock); - return XFS_ERROR(-EINVAL); - } - - if (!need_i_mutex && (VN_CACHED(vp) || pos > xip->i_size)) { - xfs_iunlock(xip, XFS_ILOCK_EXCL|iolock); - iolock = XFS_IOLOCK_EXCL; - locktype = VRWLOCK_WRITE; - need_i_mutex = 1; - mutex_lock(&inode->i_mutex); - xfs_ilock(xip, XFS_ILOCK_EXCL|iolock); - goto start; - } - } - - new_size = pos + count; - if (new_size > xip->i_size) - io->io_new_size = new_size; - if ((DM_EVENT_ENABLED(vp->v_vfsp, xip, DM_EVENT_WRITE) && !(ioflags & IO_INVIS) && !eventsent)) { - loff_t savedsize = pos; int dmflags = FILP_DELAY_FLAG(file); if (need_i_mutex) @@ -774,10 +748,35 @@ start: * event prevents another call to XFS_SEND_DATA, which is * what allows the size to change in the first place. */ - if ((file->f_flags & O_APPEND) && savedsize != xip->i_size) + if ((file->f_flags & O_APPEND) && pos != xip->i_size) goto start; } + if (ioflags & IO_ISDIRECT) { + xfs_buftarg_t *target = + (xip->i_d.di_flags & XFS_DIFLAG_REALTIME) ? + mp->m_rtdev_targp : mp->m_ddev_targp; + + if ((pos & target->bt_smask) || (count & target->bt_smask)) { + xfs_iunlock(xip, XFS_ILOCK_EXCL|iolock); + return XFS_ERROR(-EINVAL); + } + + if (!need_i_mutex && (VN_CACHED(vp) || pos > xip->i_size)) { + xfs_iunlock(xip, XFS_ILOCK_EXCL|iolock); + iolock = XFS_IOLOCK_EXCL; + locktype = VRWLOCK_WRITE; + need_i_mutex = 1; + mutex_lock(&inode->i_mutex); + xfs_ilock(xip, XFS_ILOCK_EXCL|iolock); + goto start; + } + } + + new_size = pos + count; + if (new_size > xip->i_size) + io->io_new_size = new_size; + if (likely(!(ioflags & IO_INVIS))) { file_update_time(file); xfs_ichgtime_fast(xip, inode, |