iget: stop CIFS from using iget() and read_inode()

Stop the CIFS filesystem from using iget() and read_inode().  Replace
cifs_read_inode() with cifs_iget(), and call that instead of iget().
cifs_iget() then uses iget_locked() directly and returns a proper error code
instead of an inode in the event of an error.

cifs_read_super() now returns any error incurred when getting the root inode
instead of ENOMEM.

cifs_iget() needs examining.  The comment "can not call macro FreeXid here
since in a void func" is no longer true.

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Steven French <sfrench@us.ibm.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 19 insertions, 3 deletions

diff --git a/fs/cifs/inode.c b/fs/cifs/inode.c
index 47f2621001e..b1a4a65eaa0 100644
--- a/fs/cifs/inode.c
+++ b/fs/cifs/inode.c
@@ -586,10 +586,18 @@ static const struct inode_operations cifs_ipc_inode_ops = {
 };
 
 /* gets root inode */
-void cifs_read_inode(struct inode *inode)
+struct inode *cifs_iget(struct super_block *sb, unsigned long ino)
 {
-        int xid, rc;
+        int xid;
         struct cifs_sb_info *cifs_sb;
+        struct inode *inode;
+        long rc;
+
+        inode = iget_locked(sb, ino);
+        if (!inode)
+                return ERR_PTR(-ENOMEM);
+        if (!(inode->i_state & I_NEW))
+                return inode;
 
         cifs_sb = CIFS_SB(inode->i_sb);
         xid = GetXid();
@@ -606,10 +614,18 @@ void cifs_read_inode(struct inode *inode)
                 inode->i_fop = &simple_dir_operations;
                 inode->i_uid = cifs_sb->mnt_uid;
                 inode->i_gid = cifs_sb->mnt_gid;
+                _FreeXid(xid);
+                iget_failed(inode);
+                return ERR_PTR(rc);
         }
 
-        /* can not call macro FreeXid here since in a void func */
+        unlock_new_inode(inode);
+
+        /* can not call macro FreeXid here since in a void func
+         * TODO: This is no longer true
+         */
         _FreeXid(xid);
+        return inode;
 }
 
 int cifs_unlink(struct inode *inode, struct dentry *direntry)