nfs: don't create zero-length requests
NFS doesn't expect requests with wb_bytes set to zero and may make
unexpected decisions about how to handle that request at the page IO layer.
Skip request creation if we won't have any wb_bytes in the request.
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Weston Andros Adamson <dros@primarydata.com>
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 0b949a0..b5f3da3 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -1291,6 +1291,9 @@
dprintk("NFS: nfs_updatepage(%pD2 %d@%lld)\n",
file, count, (long long)(page_file_offset(page) + offset));
+ if (!count)
+ goto out;
+
if (nfs_can_extend_write(file, page, inode)) {
count = max(count + offset, nfs_page_length(page));
offset = 0;
@@ -1301,7 +1304,7 @@
nfs_set_pageerror(page);
else
__set_page_dirty_nobuffers(page);
-
+out:
dprintk("NFS: nfs_updatepage returns %d (isize %lld)\n",
status, (long long)i_size_read(inode));
return status;