f2fs: fix to initialize i_current_depth according to inode type

i_current_depth is used only for directory inode, but its space is
shared with i_gc_failures field used for regular inode, in order to
avoid affecting i_gc_failures' value, this patch fixes to initialize
the union's fields according to inode type.
Signed-off-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>

fs/f2fs/inode.c

@@ -232,8 +232,10 @@ static int do_read_inode(struct inode *inode)
 	inode->i_ctime.tv_nsec = le32_to_cpu(ri->i_ctime_nsec);
 	inode->i_mtime.tv_nsec = le32_to_cpu(ri->i_mtime_nsec);
 	inode->i_generation = le32_to_cpu(ri->i_generation);
-
-	fi->i_current_depth = le32_to_cpu(ri->i_current_depth);
+	if (S_ISDIR(inode->i_mode))
+		fi->i_current_depth = le32_to_cpu(ri->i_current_depth);
+	else if (S_ISREG(inode->i_mode))
+		fi->i_gc_failures = le16_to_cpu(ri->i_gc_failures);
 	fi->i_xattr_nid = le32_to_cpu(ri->i_xattr_nid);
 	fi->i_flags = le32_to_cpu(ri->i_flags);
 	fi->flags = 0;
@@ -422,7 +424,11 @@ void update_inode(struct inode *inode, struct page *node_page)
 	ri->i_atime_nsec = cpu_to_le32(inode->i_atime.tv_nsec);
 	ri->i_ctime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
 	ri->i_mtime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec);
-	ri->i_current_depth = cpu_to_le32(F2FS_I(inode)->i_current_depth);
+	if (S_ISDIR(inode->i_mode))
+		ri->i_current_depth =
+			cpu_to_le32(F2FS_I(inode)->i_current_depth);
+	else if (S_ISREG(inode->i_mode))
+		ri->i_gc_failures = cpu_to_le16(F2FS_I(inode)->i_gc_failures);
 	ri->i_xattr_nid = cpu_to_le32(F2FS_I(inode)->i_xattr_nid);
 	ri->i_flags = cpu_to_le32(F2FS_I(inode)->i_flags);
 	ri->i_pino = cpu_to_le32(F2FS_I(inode)->i_pino);

fs/f2fs/namei.c

@@ -54,6 +54,9 @@ static struct inode *f2fs_new_inode(struct inode *dir, umode_t mode)
 			F2FS_I(inode)->i_crtime = current_time(inode);
 	inode->i_generation = sbi->s_next_generation++;
 
+	if (S_ISDIR(inode->i_mode))
+		F2FS_I(inode)->i_current_depth = 1;
+
 	err = insert_inode_locked(inode);
 	if (err) {
 		err = -EINVAL;

fs/f2fs/super.c

@@ -830,7 +830,6 @@ static struct inode *f2fs_alloc_inode(struct super_block *sb)
 
 	/* Initialize f2fs-specific inode info */
 	atomic_set(&fi->dirty_pages, 0);
-	fi->i_current_depth = 1;
 	init_rwsem(&fi->i_sem);
 	INIT_LIST_HEAD(&fi->dirty_list);
 	INIT_LIST_HEAD(&fi->gdirty_list);