cifs: update the inode cache with the results from a FIND_*

linux-2.6.32-504.el6-cifs_update_inode_cache.patch

Subject: cifs: update the inode cache with the results from a FIND_*

See also: https://github.com/torvalds/linux/commit/cd60042cc1392e79410dc8de9e9c1abb38a29e57
See also: https://github.com/torvalds/linux/commit/2f2591a34db6c9361faa316c91a6e320cb4e6aee
================================
diff -uNrp kernel-2.6.32-504.el6.orig/linux-2.6.32-504.el6.x86_64/fs/cifs/readdir.c kernel-2.6.32-504.el6.new/linux-2.6.32-504.el6.x86_64/fs/cifs/readdir.c
--- linux-2.6.32-504.el6.x86_64/fs/cifs/readdir.c       2014-09-16 14:20:00.000000000 +0900
+++ linux-2.6.32-504.el6.x86_64/fs/cifs/readdir.c       2014-11-07 06:51:30.746015526 +0900
@@ -74,6 +74,7 @@ cifs_readdir_lookup(struct dentry *paren
        struct dentry *dentry, *alias;
        struct inode *inode;
        struct super_block *sb = parent->d_inode->i_sb;
+       struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
 
        cFYI(1, "For %s", name->name);
 
@@ -84,11 +85,28 @@ cifs_readdir_lookup(struct dentry *paren
 
        dentry = d_lookup(parent, name);
        if (dentry) {
-               /* FIXME: check for inode number changes? */
-               if (dentry->d_inode != NULL)
-                       return dentry;
-               d_drop(dentry);
+               int err;
+
+               inode = dentry->d_inode;
+               if (inode) {
+                       /*
+                        * If we're generating inode numbers, then we don't
+                        * want to clobber the existing one with the one that
+                        * the readdir code created.
+                        */
+                       if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM))
+                               fattr->cf_uniqueid = CIFS_I(inode)->uniqueid;
+
+                       /* update inode in place if i_ino didn't change */
+                       if (CIFS_I(inode)->uniqueid == fattr->cf_uniqueid) {
+                               cifs_fattr_to_inode(inode, fattr);
+                               return dentry;
+                       }
+               }
+               err = d_invalidate(dentry);
                dput(dentry);
+               if (err)
+                       return NULL;
        }
 
        /*