iget: stop EXT4 from using iget() and read_inode()

Stop the EXT4 filesystem from using iget() and read_inode().  Replace
ext4_read_inode() with ext4_iget(), and call that instead of iget().
ext4_iget() then uses iget_locked() directly and returns a proper error code
instead of an inode in the event of an error.

ext4_fill_super() returns any error incurred when getting the root inode
instead of EINVAL.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: "Theodore Ts'o" <tytso@mit.edu>
Acked-by: Jan Kara <jack@suse.cz>
Cc: <linux-ext4@vger.kernel.org>
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, 6 deletions

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 0e9055c..f4e3874 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -2680,21 +2680,31 @@ static blkcnt_t ext4_inode_blocks(struct ext4_inode *raw_inode,
 	}
 }
 
-void ext4_read_inode(struct inode * inode)
+struct inode *ext4_iget(struct super_block *sb, unsigned long ino)
 {
 	struct ext4_iloc iloc;
 	struct ext4_inode *raw_inode;
-	struct ext4_inode_info *ei = EXT4_I(inode);
+	struct ext4_inode_info *ei;
 	struct buffer_head *bh;
+	struct inode *inode;
+	long ret;
 	int block;
 
+	inode = iget_locked(sb, ino);
+	if (!inode)
+		return ERR_PTR(-ENOMEM);
+	if (!(inode->i_state & I_NEW))
+		return inode;
+
+	ei = EXT4_I(inode);
 #ifdef CONFIG_EXT4DEV_FS_POSIX_ACL
 	ei->i_acl = EXT4_ACL_NOT_CACHED;
 	ei->i_default_acl = EXT4_ACL_NOT_CACHED;
 #endif
 	ei->i_block_alloc_info = NULL;
 
-	if (__ext4_get_inode_loc(inode, &iloc, 0))
+	ret = __ext4_get_inode_loc(inode, &iloc, 0);
+	if (ret < 0)
 		goto bad_inode;
 	bh = iloc.bh;
 	raw_inode = ext4_raw_inode(&iloc);
@@ -2720,6 +2730,7 @@ void ext4_read_inode(struct inode * inode)
 		    !(EXT4_SB(inode->i_sb)->s_mount_state & EXT4_ORPHAN_FS)) {
 			/* this inode is deleted */
 			brelse (bh);
+			ret = -ESTALE;
 			goto bad_inode;
 		}
 		/* The only unlinked inodes we let through here have
@@ -2758,6 +2769,7 @@ void ext4_read_inode(struct inode * inode)
 		if (EXT4_GOOD_OLD_INODE_SIZE + ei->i_extra_isize >
 		    EXT4_INODE_SIZE(inode->i_sb)) {
 			brelse (bh);
+			ret = -EIO;
 			goto bad_inode;
 		}
 		if (ei->i_extra_isize == 0) {
@@ -2811,11 +2823,12 @@ void ext4_read_inode(struct inode * inode)
 	}
 	brelse (iloc.bh);
 	ext4_set_inode_flags(inode);
-	return;
+	unlock_new_inode(inode);
+	return inode;
 
 bad_inode:
-	make_bad_inode(inode);
-	return;
+	iget_failed(inode);
+	return ERR_PTR(ret);
 }
 
 static int ext4_inode_blocks_set(handle_t *handle,