[ 01/38] CIFS use sensible file nlink values if unprovided

From: Greg Kroah-Hartman
Date: Fri Jul 19 2013 - 01:51:53 EST


3.9-stable review patch. If anyone has any objections, please let me know.

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

From: Steve French <smfrench@xxxxxxxxx>

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@xxxxxxx>
Signed-off-by: Steve French <smfrench@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
fs/cifs/inode.c | 5 +++++
1 file changed, 5 insertions(+)

--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -556,6 +556,11 @@ cifs_all_info_to_fattr(struct cifs_fattr
fattr->cf_mode &= ~(S_IWUGO);

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

fattr->cf_uid = cifs_sb->mnt_uid;


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