[ 3.5.y.z extended stable ] Patch "[CIFS] use sensible file nlink values if unprovided" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    [CIFS] use sensible file nlink values if unprovided

to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.5.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From dd0bade709fffade7471fd1d59e4be11e5ec2da1 Mon Sep 17 00:00:00 2001
From: Steve French <smfrench at gmail.com>
Date: Thu, 4 Jul 2013 14:38:48 -0500
Subject: [PATCH] [CIFS] use sensible file nlink values if unprovided

commit 6658b9f70ebca5fc0795b1d6d733996af1e2caa7 upstream.

Certain servers may not set the NumberOfLinks field in query file/path
info responses. In such a case, cifs_inode_needs_reval() assumes that
all regular files are hardlinks and triggers revalidation, leading to
excessive and unnecessary network traffic.

This change hardcodes cf_nlink (and subsequently i_nlink) when not
returned by the server, similar to what already occurs in cifs_mkdir().

Signed-off-by: David Disseldorp <ddiss at suse.de>
Signed-off-by: Steve French <smfrench at gmail.com>
[ luis: backported to 3.5:
  - replaced cifs_dbg() by cFYI() ]
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 fs/cifs/inode.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 6fbfbdb..293226e 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -549,6 +549,11 @@ cifs_all_info_to_fattr(struct cifs_fattr *fattr, FILE_ALL_INFO *info,
 			fattr->cf_mode &= ~(S_IWUGO);

 		fattr->cf_nlink = le32_to_cpu(info->NumberOfLinks);
+		if (fattr->cf_nlink < 1) {
+			cFYI(1, "replacing bogus file nlink value %u\n",
+				fattr->cf_nlink);
+			fattr->cf_nlink = 1;
+		}
 	}

 	fattr->cf_uid = cifs_sb->mnt_uid;
--
1.8.1.2