Re: [patch] optimize o_direct on block device - v3

[Michael Reed <mdr@sgi.com>]

Hi Andrew,

Thanks again for finding the fix to the problem I reported.
Can you tell me when I might expect this fix to show up in
2.6.20-rc?

Thanks,
 Mike


Andrew Morton wrote:
> On Thu, 11 Jan 2007 13:21:57 -0600
> Michael Reed <mdr@sgi.com> wrote:
> 
>> Testing on my ia64 system reveals that this patch introduces a
>> data integrity error for direct i/o to a block device.  Device
>> errors which result in i/o failure do not propagate to the
>> process issuing direct i/o to the device.
>>
>> This can be reproduced by doing writes to a fibre channel block
>> device and then disabling the switch port connecting the host
>> adapter to the switch.
>>
> 
> Does this fix it?
> 
> <thwaps Ken>
> <thwaps compiler>
> <adds new entry to Documentation/SubmitChecklist>
> 
> diff -puN fs/block_dev.c~a fs/block_dev.c
> --- a/fs/block_dev.c~a
> +++ a/fs/block_dev.c
> @@ -146,7 +146,7 @@ static int blk_end_aio(struct bio *bio, 
>  		iocb->ki_nbytes = -EIO;
>  
>  	if (atomic_dec_and_test(bio_count)) {
> -		if (iocb->ki_nbytes < 0)
> +		if ((long)iocb->ki_nbytes < 0)
>  			aio_complete(iocb, iocb->ki_nbytes, 0);
>  		else
>  			aio_complete(iocb, iocb->ki_left, 0);
> _
> 
> 
> -
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