Re: [PATCH v3 2/6] ext4: move inode extension/truncate code out from ext4_iomap_end()

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Mon 23-09-19 18:21:15, Jan Kara wrote:
> On Thu 12-09-19 21:04:00, Matthew Bobrowski wrote:
> So I'd just call ext4_handle_inode_extension() unconditionally like:
> 
> 	error = ext4_handle_inode_extension(inode, offset, ret, len);
> 
> and have a quick check at the beginning of that function to avoid starting
> transaction when there isn't anything to do. Something like:
> 
> 	/*
> 	 * DIO and DAX writes get exclusion from truncate (i_rwsem) and
> 	 * page writeback (i_rwsem and flushing all dirty pages).
> 	 */
> 	WARN_ON_ONCE(i_size_read(inode) != EXT4_I(inode)->i_disksize);
> 	if (offset + count <= i_size_read(inode))
> 		return 0;

One correction here. With commit 45d8ec4d9fd54 in mind this should be:

 	/*
 	 * DIO and DAX writes get exclusion from truncate (i_rwsem). There
 	 * can be pending delalloc writeback beyond the range written by
 	 * DIO though.
 	 */
 	WARN_ON_ONCE(i_size_read(inode) < EXT4_I(inode)->i_disksize);
 	if (offset + count <= EXT4_I(inode)->i_disksize)
 		return 0;

								Honza

> 	if (len < 0)
> 		goto truncate;
> 
> 	... do the heavylifting with transaction start, inode size update,
> 	and orphan handling...
> 
> 	if (truncate) {
> truncate:
> 		ext4_truncate_failed_write(inode);
> orphan_del:
> 		/*
> 		 * If the truncate operation failed early the inode
> 		 * may still be on the orphan list. In that case, we
> 		 * need try remove the inode from the linked list in
> 		 * memory.
> 		 */
> 		if (inode->i_nlink)
> 			ext4_orphan_del(NULL, inode);
> 	}
-- 
Jan Kara <jack@xxxxxxxx>
SUSE Labs, CR



[Index of Archives]     [Linux Ext4 Filesystem]     [Union Filesystem]     [Filesystem Testing]     [Ceph Users]     [Ecryptfs]     [AutoFS]     [Kernel Newbies]     [Share Photos]     [Security]     [Netfilter]     [Bugtraq]     [Yosemite News]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux Cachefs]     [Reiser Filesystem]     [Linux RAID]     [Samba]     [Device Mapper]     [CEPH Development]

  Powered by Linux