xfs: flush for older, xfs specific ioctls

837a6e7f5cdb ("fs: add generic UNRESVSP and ZERO_RANGE ioctl handlers") changed
ioctls XFS_IOC_UNRESVSP XFS_IOC_UNRESVSP64 and XFS_IOC_ZERO_RANGE to be generic
instead of xfs specific.

Because of this change, 36f11775da75 ("xfs: properly serialise fallocate against
AIO+DIO") needed adaptation, as 5.4 still uses the xfs specific ioctls.

Without this, xfstests xfs/242 and xfs/290 fail. Both of these tests test
XFS_IOC_ZERO_RANGE.

Fixes: 36f11775da75 ("xfs: properly serialise fallocate against AIO+DIO")
Tested-by: Andy Strohman <astroh@amazon.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index bf0435dbec43646ee1a91815eb93ab8ab414410a..b3021d9b34a5e6395bfe699a0f30a6c6d21275a4 100644 (file)
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -622,7 +622,6 @@ xfs_ioc_space(
        error = xfs_break_layouts(inode, &iolock, BREAK_UNMAP);
        if (error)
                goto out_unlock;
-       inode_dio_wait(inode);
 
        switch (bf->l_whence) {
        case 0: /*SEEK_SET*/
@@ -668,6 +667,31 @@ xfs_ioc_space(
                goto out_unlock;
        }
 
+       /*
+        * Must wait for all AIO to complete before we continue as AIO can
+        * change the file size on completion without holding any locks we
+        * currently hold. We must do this first because AIO can update both
+        * the on disk and in memory inode sizes, and the operations that follow
+        * require the in-memory size to be fully up-to-date.
+        */
+       inode_dio_wait(inode);
+
+       /*
+        * Now that AIO and DIO has drained we can flush and (if necessary)
+        * invalidate the cached range over the first operation we are about to
+        * run. We include zero range here because it starts with a hole punch
+        * over the target range.
+        */
+       switch (cmd) {
+       case XFS_IOC_ZERO_RANGE:
+       case XFS_IOC_UNRESVSP:
+       case XFS_IOC_UNRESVSP64:
+               error = xfs_flush_unmap_range(ip, bf->l_start, bf->l_len);
+               if (error)
+                       goto out_unlock;
+               break;
+       }
+
        switch (cmd) {
        case XFS_IOC_ZERO_RANGE:
                flags |= XFS_PREALLOC_SET;