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

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

jfs_fill_super() returns any error incurred when getting the root inode
instead of EINVAL.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Dave Kleikamp <shaggy@linux.vnet.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>
diff --git a/fs/jfs/inode.c b/fs/jfs/inode.c
index 4672013..2103397 100644
--- a/fs/jfs/inode.c
+++ b/fs/jfs/inode.c
@@ -31,11 +31,21 @@
 #include "jfs_debug.h"
 
 
-void jfs_read_inode(struct inode *inode)
+struct inode *jfs_iget(struct super_block *sb, unsigned long ino)
 {
-	if (diRead(inode)) {
-		make_bad_inode(inode);
-		return;
+	struct inode *inode;
+	int ret;
+
+	inode = iget_locked(sb, ino);
+	if (!inode)
+		return ERR_PTR(-ENOMEM);
+	if (!(inode->i_state & I_NEW))
+		return inode;
+
+	ret = diRead(inode);
+	if (ret < 0) {
+		iget_failed(inode);
+		return ERR_PTR(ret);
 	}
 
 	if (S_ISREG(inode->i_mode)) {
@@ -55,6 +65,8 @@
 		inode->i_op = &jfs_file_inode_operations;
 		init_special_inode(inode, inode->i_mode, inode->i_rdev);
 	}
+	unlock_new_inode(inode);
+	return inode;
 }
 
 /*