[prev in list] [next in list] [prev in thread] [next in thread] 

List:       fuse-devel
Subject:    Re: [fuse-devel] [PATCH] fuse: Do not mask return value from fuse_direct_io for partially valid data
From:       Ashish Samant <ashish.samant () oracle ! com>
Date:       2016-03-14 18:18:26
Message-ID: 56E70072.3070702 () oracle ! com
[Download RAW message or body]



On 03/14/2016 09:47 AM, Miklos Szeredi wrote:
> On Wed, Mar 09, 2016 at 10:57:51AM -0800, Ashish Samant wrote:
>> If a user calls writev/readv in direct io mode with partially valid data
>> in the iovec array such that any iovec other than the first one in the
>> array contains invalid data, we currently return the error for the invalid
>> iovec.
>>
>> Instead, we should return the number of bytes already written/read and not
>> the error as we do in the non direct_io case.
> Okay, the patch looks good in theory.  Except it doesn't compile.
Oops. Sorry about that. It is because err is defined in the while loop 
and I was using it outside the loop.
>
> It would be good to know that you at least tried to compile the patch before
> sending it and preferably even test out the functionality and that it fixes the
> bug (see also Documentations/SubmitChecklist filtered with common sense).
Yes, I did compile and test a slightly different version of the patch 
before sending it out and it does fix the bug. I will send v2.

Thanks,
Ashish
>
> Thanks,
> Miklos
>
>> Reported-by: Alexey Kodanev <alexey.kodanev@oracle.com>
>> Signed-off-by: Ashish Samant <ashish.samant@oracle.com>
>> ---
>>   fs/fuse/file.c | 6 ++----
>>   1 file changed, 2 insertions(+), 4 deletions(-)
>>
>> diff --git a/fs/fuse/file.c b/fs/fuse/file.c
>> index b03d253..f135008 100644
>> --- a/fs/fuse/file.c
>> +++ b/fs/fuse/file.c
>> @@ -1333,10 +1333,8 @@ ssize_t fuse_direct_io(struct fuse_io_priv *io, struct iov_iter *iter,
>>   		fl_owner_t owner = current->files;
>>   		size_t nbytes = min(count, nmax);
>>   		int err = fuse_get_user_pages(req, iter, &nbytes, write);
>> -		if (err) {
>> -			res = err;
>> +		if (err)
>>   			break;
>> -		}
>>   
>>   		if (write)
>>   			nres = fuse_send_write(req, io, pos, nbytes, owner);
>> @@ -1374,7 +1372,7 @@ ssize_t fuse_direct_io(struct fuse_io_priv *io, struct iov_iter *iter,
>>   	if (res > 0)
>>   		*ppos = pos;
>>   
>> -	return res;
>> +	return res > 0 ? res : err;
>>   }
>>   EXPORT_SYMBOL_GPL(fuse_direct_io);
>>   
>> -- 
>> 1.9.1
>>


------------------------------------------------------------------------------
Transform Data into Opportunity.
Accelerate data analysis in your applications with
Intel Data Analytics Acceleration Library.
Click to learn more.
http://pubads.g.doubleclick.net/gampad/clk?id=278785231&iu=/4140
-- 
fuse-devel mailing list
To unsubscribe or subscribe, visit https://lists.sourceforge.net/lists/listinfo/fuse-devel
[prev in list] [next in list] [prev in thread] [next in thread]