[PATCH 3.2 054/101] nfsd: update mtime on truncate

[Ben Hutchings]

3.2.89-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Christoph Hellwig <h...@lst.de>

commit f0c63124a6165792f6e37e4b5983792d009e1ce8 upstream.

This fixes a failure in xfstests generic/313 because nfs doesn't update
mtime on a truncate.  The protocol requires this to be done implicity
for a size changing setattr.

Signed-off-by: Christoph Hellwig <h...@lst.de>
Signed-off-by: J. Bruce Fields <bfie...@redhat.com>
Signed-off-by: Ben Hutchings <b...@decadent.org.uk>
---
 fs/nfsd/vfs.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -450,6 +450,16 @@ nfsd_setattr(struct svc_rqst *rqstp, str
                if (err)
                        goto out;
                size_change = 1;
+
+               /*
+                * RFC5661, Section 18.30.4:
+                *   Changing the size of a file with SETATTR indirectly
+                *   changes the time_modify and change attributes.
+                *
+                * (and similar for the older RFCs)
+                */
+               if (iap->ia_size != i_size_read(inode))
+                       iap->ia_valid |= ATTR_MTIME;
        }
 
        iap->ia_valid |= ATTR_CTIME;