hfsplus: rework processing of hfs_btree_write() returned error

Add to hfs_btree_write() a return of -EIO on failure of b-tree node
searching.  Also add logic ofor processing errors from hfs_btree_write()
in hfsplus_system_write_inode() with a message about b-tree writing
failure.

[akpm@linux-foundation.org: reduce scope of `err', print errno on error]
Signed-off-by: Vyacheslav Dubeyko <slava@dubeyko.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: Hin-Tak Leung <htl10@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/hfsplus/btree.c

@@ -159,7 +159,7 @@ void hfs_btree_close(struct hfs_btree *tree)
 	kfree(tree);
 }
 
-void hfs_btree_write(struct hfs_btree *tree)
+int hfs_btree_write(struct hfs_btree *tree)
 {
 	struct hfs_btree_header_rec *head;
 	struct hfs_bnode *node;
@@ -168,7 +168,7 @@ void hfs_btree_write(struct hfs_btree *tree)
 	node = hfs_bnode_find(tree, 0);
 	if (IS_ERR(node))
 		/* panic? */
-		return;
+		return -EIO;
 	/* Load the header */
 	page = node->page[0];
 	head = (struct hfs_btree_header_rec *)(kmap(page) +
@@ -186,6 +186,7 @@ void hfs_btree_write(struct hfs_btree *tree)
 	kunmap(page);
 	set_page_dirty(page);
 	hfs_bnode_put(node);
+	return 0;
 }
 
 static struct hfs_bnode *hfs_bmap_new_bmap(struct hfs_bnode *prev, u32 idx)

fs/hfsplus/hfsplus_fs.h

@@ -335,7 +335,7 @@ int hfsplus_block_free(struct super_block *, u32, u32);
 /* btree.c */
 struct hfs_btree *hfs_btree_open(struct super_block *, u32);
 void hfs_btree_close(struct hfs_btree *);
-void hfs_btree_write(struct hfs_btree *);
+int hfs_btree_write(struct hfs_btree *);
 struct hfs_bnode *hfs_bmap_alloc(struct hfs_btree *);
 void hfs_bmap_free(struct hfs_bnode *);
 

fs/hfsplus/super.c

@@ -127,8 +127,14 @@ static int hfsplus_system_write_inode(struct inode *inode)
 		hfsplus_mark_mdb_dirty(inode->i_sb);
 	}
 	hfsplus_inode_write_fork(inode, fork);
-	if (tree)
-		hfs_btree_write(tree);
+	if (tree) {
+		int err = hfs_btree_write(tree);
+		if (err) {
+			printk(KERN_ERR "hfs: b-tree write err: %d, ino %lu\n",
+					err, inode->i_ino);
+			return err;
+		}
+	}
 	return 0;
 }