ext4: allow ext4_ext_truncate() to return an error

Return errors to the caller instead of declaring the file system
corrupted.

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>

fs/ext4/ext4.h

@@ -3128,7 +3128,7 @@ extern int ext4_ext_writepage_trans_blocks(struct inode *, int);
 extern int ext4_ext_index_trans_blocks(struct inode *inode, int extents);
 extern int ext4_ext_map_blocks(handle_t *handle, struct inode *inode,
 			       struct ext4_map_blocks *map, int flags);
-extern void ext4_ext_truncate(handle_t *, struct inode *);
+extern int ext4_ext_truncate(handle_t *, struct inode *);
 extern int ext4_ext_remove_space(struct inode *inode, ext4_lblk_t start,
 				 ext4_lblk_t end);
 extern void ext4_ext_init(struct super_block *);

fs/ext4/extents.c

@@ -4631,7 +4631,7 @@ out2:
 	return err ? err : allocated;
 }
 
-void ext4_ext_truncate(handle_t *handle, struct inode *inode)
+int ext4_ext_truncate(handle_t *handle, struct inode *inode)
 {
 	struct super_block *sb = inode->i_sb;
 	ext4_lblk_t last_block;
@@ -4645,7 +4645,9 @@ void ext4_ext_truncate(handle_t *handle, struct inode *inode)
 
 	/* we have to know where to truncate from in crash case */
 	EXT4_I(inode)->i_disksize = inode->i_size;
-	ext4_mark_inode_dirty(handle, inode);
+	err = ext4_mark_inode_dirty(handle, inode);
+	if (err)
+		return err;
 
 	last_block = (inode->i_size + sb->s_blocksize - 1)
 			>> EXT4_BLOCK_SIZE_BITS(sb);
@@ -4657,12 +4659,9 @@ retry:
 		congestion_wait(BLK_RW_ASYNC, HZ/50);
 		goto retry;
 	}
-	if (err) {
-		ext4_std_error(inode->i_sb, err);
-		return;
-	}
-	err = ext4_ext_remove_space(inode, last_block, EXT_MAX_BLOCKS - 1);
-	ext4_std_error(inode->i_sb, err);
+	if (err)
+		return err;
+	return ext4_ext_remove_space(inode, last_block, EXT_MAX_BLOCKS - 1);
 }
 
 static int ext4_alloc_file_blocks(struct file *file, ext4_lblk_t offset,

fs/ext4/inode.c

@@ -4173,11 +4173,13 @@ int ext4_truncate(struct inode *inode)
 	ext4_discard_preallocations(inode);
 
 	if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
-		ext4_ext_truncate(handle, inode);
+		err = ext4_ext_truncate(handle, inode);
 	else
 		ext4_ind_truncate(handle, inode);
 
 	up_write(&ei->i_data_sem);
+	if (err)
+		goto out_stop;
 
 	if (IS_SYNC(inode))
 		ext4_handle_sync(handle);