From: Boaz Harrosh <bharrosh@panasas.com>
Subject: Re: [patch 5/5] ext2: convert to use the new truncate convention.
Date: Mon, 17 Aug 2009 14:09:54 +0300
Message-ID: <4A893A82.6030801@panasas.com>
References: <20090816102533.329473921@suse.de> <20090816102856.846088617@suse.de> <20090816201626.GA23048@infradead.org> <20090817064216.GC9962@wotan.suse.de>
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Cc: Christoph Hellwig <hch@infradead.org>,
	Andrew Morton <akpm@linux-foundation.org>,
	linux-fsdevel@vger.kernel.org, linux-ext4@vger.kernel.org,
	Christoph Hellwig <hch@lst.de>
To: Nick Piggin <npiggin@suse.de>
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On 08/17/2009 09:42 AM, Nick Piggin wrote:
> On Sun, Aug 16, 2009 at 04:16:26PM -0400, Christoph Hellwig wrote:
>> On Sun, Aug 16, 2009 at 08:25:38PM +1000, npiggin@suse.de wrote:
>>> @@ -66,9 +68,10 @@ void ext2_delete_inode (struct inode * i
>>>  	mark_inode_dirty(inode);
>>>  	ext2_write_inode(inode, inode_needs_sync(inode));
>>>  
>>> +	/* XXX: where is truncate_inode_pages? */
>>>  	inode->i_size = 0;
>>>  	if (inode->i_blocks)
>>> -		ext2_truncate (inode);
>>> +		ext2_truncate_blocks(inode, 0);
>>>  	ext2_free_inode (inode);
>>
>> At the beginning of the function, just before the diff window.  Because
>> this is ->delete_inode we truncate away all pages, down to offset 0.
> 
> OK, weird. I thought I couldn't see it when I wrote that :) maybe my
> tree was corrupted or I'm stupid.
> 
> 
>>> +static void ext2_truncate_blocks(struct inode *inode, loff_t offset)
>>> +{
>>> +	/*
>>> +	 * XXX: it seems like a bug here that we don't allow
>>> +	 * IS_APPEND inode to have blocks-past-i_size trimmed off.
>>> +	 * review and fix this.
>>> +	 */
>>> +	if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
>>> +	    S_ISLNK(inode->i_mode)))
>>> +		return -EINVAL;
>>> +	if (ext2_inode_is_fast_symlink(inode))
>>> +		return -EINVAL;
>>> +	if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
>>> +		return -EPERM;
>>> +	__ext2_truncate_blocks(inode, offset);
>>
>> Yes, I think the IS_APPEND(inode) || IS_IMMUTABLE(inode) checks should move
>> into ext2_setsize.  But let's leave that for a separate patch.
> 
> Yeah agreed.
> 
>  
>> Btw, the above code gives me warnings like this:
>>
>> /home/hch/work/linux-2.6/fs/ext2/inode.c: In function
>> 'ext2_truncate_blocks':
>> /home/hch/work/linux-2.6/fs/ext2/inode.c:1158: warning: 'return' with a
>> value, in function returning void
>> /home/hch/work/linux-2.6/fs/ext2/inode.c:1160: warning: 'return' with a
>> value, in function returning void
>> /home/hch/work/linux-2.6/fs/ext2/inode.c:1162: warning: 'return' with a
>> value, in function returning void
>>
>> because you try to return errors from a function delcared as void.
> 
> Hm, sorry. I thought it was in good shape... I'll recheck that I sent
> out the correct versions and resend according to feedback from you
> and Hugh.
> 
> Thanks,
> Nick
> 

Nick do you have a public tree with these latest patches? I would like to
try out an exofs conversion and testing.

Thanks
Boaz