1 files changed, 32 insertions, 29 deletions

diff --git a/fs/xfs/linux-2.6/xfs_lrw.c b/fs/xfs/linux-2.6/xfs_lrw.c
index 8e46c9798fb..80fe3123347 100644
--- a/fs/xfs/linux-2.6/xfs_lrw.c
+++ b/fs/xfs/linux-2.6/xfs_lrw.c
@@ -649,7 +649,7 @@ xfs_write(
         bhv_vrwlock_t           locktype;
         size_t                  ocount = 0, count;
         loff_t                  pos;
-        int                     need_i_mutex = 1, need_flush = 0;
+        int                     need_i_mutex;
 
         XFS_STATS_INC(xs_write_calls);
 
@@ -689,39 +689,20 @@ xfs_write(
         if (XFS_FORCED_SHUTDOWN(mp))
                 return -EIO;
 
-        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))
-                        return XFS_ERROR(-EINVAL);
-
-                if (!VN_CACHED(vp) && pos < i_size_read(inode))
-                        need_i_mutex = 0;
-
-                if (VN_CACHED(vp))
-                        need_flush = 1;
-        }
-
 relock:
-        if (need_i_mutex) {
+        if (ioflags & IO_ISDIRECT) {
+                iolock = XFS_IOLOCK_SHARED;
+                locktype = VRWLOCK_WRITE_DIRECT;
+                need_i_mutex = 0;
+        } else {
                 iolock = XFS_IOLOCK_EXCL;
                 locktype = VRWLOCK_WRITE;
-
+                need_i_mutex = 1;
                 mutex_lock(&inode->i_mutex);
-        } else {
-                iolock = XFS_IOLOCK_SHARED;
-                locktype = VRWLOCK_WRITE_DIRECT;
         }
 
         xfs_ilock(xip, XFS_ILOCK_EXCL|iolock);
 
-        isize = i_size_read(inode);
-
-        if (file->f_flags & O_APPEND)
-                *offset = isize;
-
 start:
         error = -generic_write_checks(file, &pos, &count,
                                         S_ISBLK(inode->i_mode));
@@ -730,6 +711,29 @@ start:
                 goto out_unlock_mutex;
         }
 
+        isize = i_size_read(inode);
+
+        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 > isize)) {
+                        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 > isize)
                 io->io_new_size = new_size;
@@ -761,7 +765,6 @@ start:
                  * what allows the size to change in the first place.
                  */
                 if ((file->f_flags & O_APPEND) && savedsize != isize) {
-                        pos = isize = xip->i_d.di_size;
                         goto start;
                 }
         }
@@ -815,7 +818,8 @@ retry:
         current->backing_dev_info = mapping->backing_dev_info;
 
         if ((ioflags & IO_ISDIRECT)) {
-                if (need_flush) {
+                if (VN_CACHED(vp)) {
+                        WARN_ON(need_i_mutex == 0);
                         xfs_inval_cached_trace(io, pos, -1,
                                         ctooff(offtoct(pos)), -1);
                         error = bhv_vop_flushinval_pages(vp, ctooff(offtoct(pos)),
@@ -849,7 +853,6 @@ retry:
                         pos += ret;
                         count -= ret;
 
-                        need_i_mutex = 1;
                         ioflags &= ~IO_ISDIRECT;
                         xfs_iunlock(xip, iolock);
                         goto relock;