Message-ID: <24a46ae8-6e50-2f45-f099-45743bb013c4@linux.alibaba.com>
Date:   Fri, 10 Mar 2023 11:47:38 +0800
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Subject: Re: [PATCH v3 2/6] erofs: convert to use i_blockmask()
From:   Gao Xiang <hsiangkao@linux.alibaba.com>
To:     Al Viro <viro@zeniv.linux.org.uk>, Yangtao Li <frank.li@vivo.com>
Cc:     xiang@kernel.org, chao@kernel.org, huyue2@coolpad.com,
        jefflexu@linux.alibaba.com, tytso@mit.edu,
        adilger.kernel@dilger.ca, rpeterso@redhat.com, agruenba@redhat.com,
        mark@fasheh.com, jlbec@evilplan.org, joseph.qi@linux.alibaba.com,
        brauner@kernel.org, linux-erofs@lists.ozlabs.org,
        linux-kernel@vger.kernel.org, linux-ext4@vger.kernel.org,
        cluster-devel@redhat.com, ocfs2-devel@oss.oracle.com,
        linux-fsdevel@vger.kernel.org
References: <20230309152127.41427-1-frank.li@vivo.com>
 <20230309152127.41427-2-frank.li@vivo.com> <20230310031547.GD3390869@ZenIV>
 <2fa31829-03f0-7bfb-a89b-e3917c479733@linux.alibaba.com>
In-Reply-To: <2fa31829-03f0-7bfb-a89b-e3917c479733@linux.alibaba.com>
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On 2023/3/10 11:42, Gao Xiang wrote:
> Hi Al,
> 
> On 2023/3/10 11:15, Al Viro wrote:
>> On Thu, Mar 09, 2023 at 11:21:23PM +0800, Yangtao Li wrote:
>>> Use i_blockmask() to simplify code.
>>
>> Umm...  What's the branchpoint for that series?  Not the mainline -
>> there we have i_blocksize() open-coded...
> 
> Actually Yue Hu sent out a clean-up patch and I applied to -next for
> almost a week and will be upstreamed for 6.3-rc2:
> 
> https://lore.kernel.org/r/a238dca1-256f-ae2f-4a33-e54861fe4ffb@kernel.org/T/#t

Sorry this link:
https://lore.kernel.org/r/0261de31-e98b-85cd-80de-96af5a76e15c@linux.alibaba.com

Yangtao's suggestion was to use GENMASK, and I'm not sure it's a good way
since (i_blocksize(inode) - 1) is simple enough, and then it becomes like
this.

Thanks,
Gao Xiang


> 
> And then Yangtao would like to wrap this as a new VFS helper, I'm not
> sure why it's necessary since it doesn't save a lot but anyway, I'm open
> to it if VFS could have such new helper.
> 
> Thanks,
> Gao Xiang
> 
>>
>>> Signed-off-by: Yangtao Li <frank.li@vivo.com>
>>> ---
>>> v3:
>>> -none
>>> v2:
>>> -convert to i_blockmask()
>>>   fs/erofs/data.c | 2 +-
>>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/fs/erofs/data.c b/fs/erofs/data.c
>>> index 7e8baf56faa5..e9d1869cd4b3 100644
>>> --- a/fs/erofs/data.c
>>> +++ b/fs/erofs/data.c
>>> @@ -380,7 +380,7 @@ static ssize_t erofs_file_read_iter(struct kiocb *iocb, struct iov_iter *to)
>>>           if (bdev)
>>>               blksize_mask = bdev_logical_block_size(bdev) - 1;
>>>           else
>>> -            blksize_mask = i_blocksize(inode) - 1;
>>> +            blksize_mask = i_blockmask(inode);
>>>           if ((iocb->ki_pos | iov_iter_count(to) |
>>>                iov_iter_alignment(to)) & blksize_mask)
>>> -- 
>>> 2.25.1
>>>