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

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

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

[kamalesh@linux.vnet.ibm.com: build fix]
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 27 insertions, 13 deletions

diff --git a/fs/bfs/bfs.h b/fs/bfs/bfs.h
index ac7a8b1d6c3a..71faf4d23908 100644
--- a/fs/bfs/bfs.h
+++ b/fs/bfs/bfs.h
@@ -44,6 +44,8 @@ static inline struct bfs_inode_info *BFS_I(struct inode *inode)
 #define printf(format, args...) \
         printk(KERN_ERR "BFS-fs: %s(): " format, __FUNCTION__, ## args)
 
+/* inode.c */
+extern struct inode *bfs_iget(struct super_block *sb, unsigned long ino);
 
 /* file.c */
 extern const struct inode_operations bfs_file_inops;
diff --git a/fs/bfs/dir.c b/fs/bfs/dir.c
index 1fd056d0fc3d..034950cb3cbe 100644
--- a/fs/bfs/dir.c
+++ b/fs/bfs/dir.c
@@ -148,10 +148,10 @@ static struct dentry *bfs_lookup(struct inode *dir, struct dentry *dentry,
         if (bh) {
                 unsigned long ino = (unsigned long)le16_to_cpu(de->ino);
                 brelse(bh);
-                inode = iget(dir->i_sb, ino);
-                if (!inode) {
+                inode = bfs_iget(dir->i_sb, ino);
+                if (IS_ERR(inode)) {
                         unlock_kernel();
-                        return ERR_PTR(-EACCES);
+                        return ERR_CAST(inode);
                 }
         }
         unlock_kernel();
diff --git a/fs/bfs/inode.c b/fs/bfs/inode.c
index a64a71d444f5..8db623838b50 100644
--- a/fs/bfs/inode.c
+++ b/fs/bfs/inode.c
@@ -32,17 +32,22 @@ MODULE_LICENSE("GPL");
 
 void dump_imap(const char *prefix, struct super_block *s);
 
-static void bfs_read_inode(struct inode *inode)
+struct inode *bfs_iget(struct super_block *sb, unsigned long ino)
 {
-        unsigned long ino = inode->i_ino;
         struct bfs_inode *di;
+        struct inode *inode;
         struct buffer_head *bh;
         int block, off;
 
+        inode = iget_locked(sb, ino);
+        if (IS_ERR(inode))
+                return ERR_PTR(-ENOMEM);
+        if (!(inode->i_state & I_NEW))
+                return inode;
+
         if ((ino < BFS_ROOT_INO) || (ino > BFS_SB(inode->i_sb)->si_lasti)) {
                 printf("Bad inode number %s:%08lx\n", inode->i_sb->s_id, ino);
-                make_bad_inode(inode);
-                return;
+                goto error;
         }
 
         block = (ino - BFS_ROOT_INO) / BFS_INODES_PER_BLOCK + 1;
@@ -50,8 +55,7 @@ static void bfs_read_inode(struct inode *inode)
         if (!bh) {
                 printf("Unable to read inode %s:%08lx\n", inode->i_sb->s_id,
                                                                         ino);
-                make_bad_inode(inode);
-                return;
+                goto error;
         }
 
         off = (ino - BFS_ROOT_INO) % BFS_INODES_PER_BLOCK;
@@ -85,6 +89,12 @@ static void bfs_read_inode(struct inode *inode)
         inode->i_ctime.tv_nsec = 0;
 
         brelse(bh);
+        unlock_new_inode(inode);
+        return inode;
+
+error:
+        iget_failed(inode);
+        return ERR_PTR(-EIO);
 }
 
 static int bfs_write_inode(struct inode *inode, int unused)
@@ -276,7 +286,6 @@ static void destroy_inodecache(void)
 static const struct super_operations bfs_sops = {
         .alloc_inode    = bfs_alloc_inode,
         .destroy_inode  = bfs_destroy_inode,
-        .read_inode     = bfs_read_inode,
         .write_inode    = bfs_write_inode,
         .delete_inode   = bfs_delete_inode,
         .put_super      = bfs_put_super,
@@ -312,6 +321,7 @@ static int bfs_fill_super(struct super_block *s, void *data, int silent)
         struct inode *inode;
         unsigned i, imap_len;
         struct bfs_sb_info *info;
+        long ret = -EINVAL;
 
         info = kzalloc(sizeof(*info), GFP_KERNEL);
         if (!info)
@@ -346,14 +356,16 @@ static int bfs_fill_super(struct super_block *s, void *data, int silent)
                 set_bit(i, info->si_imap);
 
         s->s_op = &bfs_sops;
-        inode = iget(s, BFS_ROOT_INO);
-        if (!inode) {
+        inode = bfs_iget(s, BFS_ROOT_INO);
+        if (IS_ERR(inode)) {
+                ret = PTR_ERR(inode);
                 kfree(info->si_imap);
                 goto out;
         }
         s->s_root = d_alloc_root(inode);
         if (!s->s_root) {
                 iput(inode);
+                ret = -ENOMEM;
                 kfree(info->si_imap);
                 goto out;
         }
@@ -404,7 +416,7 @@ out:
         brelse(bh);
         kfree(info);
         s->s_fs_info = NULL;
-        return -EINVAL;
+        return ret;
 }
 
 static int bfs_get_sb(struct file_system_type *fs_type,