nfsd: fix inclusive vfs_fsync_range() end

The vfs_fsync_range() call during write processing got the end of the
range off by one.  The range is inclusive, not exclusive.  The error has
nfsd sync more data than requested -- it's correct but unnecessary
overhead.

The call during commit processing is correct so I copied that pattern in
write processing.  Maybe a helper would be nice but I kept it trivial.

This is untested.  I found it while reviewing code for something else
entirely.

Signed-off-by: Zach Brown <zab@zabbo.net>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>

1 files changed, 7 insertions, 3 deletions

diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
index 989129e2d6ea..d16076bd9a7a 100644
--- a/fs/nfsd/vfs.c
+++ b/fs/nfsd/vfs.c
@@ -938,6 +938,7 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
         int                     stable = *stablep;
         int                     use_wgather;
         loff_t                  pos = offset;
+        loff_t                  end = LLONG_MAX;
         unsigned int            pflags = current->flags;
 
         if (rqstp->rq_local)
@@ -969,10 +970,13 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
         fsnotify_modify(file);
 
         if (stable) {
-                if (use_wgather)
+                if (use_wgather) {
                         host_err = wait_for_concurrent_writes(file);
-                else
-                        host_err = vfs_fsync_range(file, offset, offset+*cnt, 0);
+                } else {
+                        if (*cnt)
+                                end = offset + *cnt - 1;
+                        host_err = vfs_fsync_range(file, offset, end, 0);
+                }
         }
 
 out_nfserr: