jbd2: Fix oops in jbd2_journal_file_inode()

[karo-tx-linux.git] / fs / ext4 / inode.c

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index dd32a2eacd0d23c07d9c1cef6e2a3d115c5a4404..c2ca04e67a4fce6a40316550215e2b2fbe107d01 100644 (file)
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -3533,6 +3533,18 @@ int ext4_punch_hole(struct inode *inode, loff_t offset, loff_t length)
                   offset;
        }
 
+       if (offset & (sb->s_blocksize - 1) ||
+           (offset + length) & (sb->s_blocksize - 1)) {
+               /*
+                * Attach jinode to inode for jbd2 if we do any zeroing of
+                * partial block
+                */
+               ret = ext4_inode_attach_jinode(inode);
+               if (ret < 0)
+                       goto out_mutex;
+
+       }
+
        first_block_offset = round_up(offset, sb->s_blocksize);
        last_block_offset = round_down((offset + length), sb->s_blocksize) - 1;
 
@@ -3601,6 +3613,31 @@ out_mutex:
        return ret;
 }
 
+int ext4_inode_attach_jinode(struct inode *inode)
+{
+       struct ext4_inode_info *ei = EXT4_I(inode);
+       struct jbd2_inode *jinode;
+
+       if (ei->jinode || !EXT4_SB(inode->i_sb)->s_journal)
+               return 0;
+
+       jinode = jbd2_alloc_inode(GFP_KERNEL);
+       spin_lock(&inode->i_lock);
+       if (!ei->jinode) {
+               if (!jinode) {
+                       spin_unlock(&inode->i_lock);
+                       return -ENOMEM;
+               }
+               ei->jinode = jinode;
+               jbd2_journal_init_jbd_inode(ei->jinode, inode);
+               jinode = NULL;
+       }
+       spin_unlock(&inode->i_lock);
+       if (unlikely(jinode != NULL))
+               jbd2_free_inode(jinode);
+       return 0;
+}
+
 /*
  * ext4_truncate()
  *
@@ -3661,6 +3698,12 @@ void ext4_truncate(struct inode *inode)
                        return;
        }
 
+       /* If we zero-out tail of the page, we have to create jinode for jbd2 */
+       if (inode->i_size & (inode->i_sb->s_blocksize - 1)) {
+               if (ext4_inode_attach_jinode(inode) < 0)
+                       return;
+       }
+
        if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS))
                credits = ext4_writepage_trans_blocks(inode);
        else