Re: [PATCH 3/3] f2fs: fix inode rwsem regression

[Chao Yu <yuchao0@huawei.com>]

On 2019/9/14 3:46, Jaegeuk Kim wrote:
> https://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs.git/commit/?h=dev&id=ebef4d7eda0d06a6ab6dc0f9e9f848276e605962

Reviewed-by: Chao Yu <yuchao0@huawei.com>

Thanks,

> 
> Merged. Thanks,
> 
> On 09/11, Goldwyn Rodrigues wrote:
>> From: Goldwyn Rodrigues <rgoldwyn@suse.com>
>>
>> This is similar to 942491c9e6d6 ("xfs: fix AIM7 regression")
>> Apparently our current rwsem code doesn't like doing the trylock, then
>> lock for real scheme.  So change our read/write methods to just do the
>> trylock for the RWF_NOWAIT case.
>>
>> We don't need a check for IOCB_NOWAIT and !direct-IO because it
>> is checked in generic_write_checks().
>>
>> Fixes: b91050a80cec ("f2fs: add nowait aio support")
>> Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
>> ---
>>  fs/f2fs/file.c | 10 +++-------
>>  1 file changed, 3 insertions(+), 7 deletions(-)
>>
>> diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
>> index 3e58a6f697dd..c6f3ef815c05 100644
>> --- a/fs/f2fs/file.c
>> +++ b/fs/f2fs/file.c
>> @@ -3134,16 +3134,12 @@ static ssize_t f2fs_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
>>  		goto out;
>>  	}
>>  
>> -	if ((iocb->ki_flags & IOCB_NOWAIT) && !(iocb->ki_flags & IOCB_DIRECT)) {
>> -		ret = -EINVAL;
>> -		goto out;
>> -	}
>> -
>> -	if (!inode_trylock(inode)) {
>> -		if (iocb->ki_flags & IOCB_NOWAIT) {
>> +	if (iocb->ki_flags & IOCB_NOWAIT) {
>> +		if (!inode_trylock(inode)) {
>>  			ret = -EAGAIN;
>>  			goto out;
>>  		}
>> +	} else {
>>  		inode_lock(inode);
>>  	}
>>  
>> -- 
>> 2.16.4
> .
>