[PATCH v2] erofs: make erofs_err() and erofs_info() support NULL sb parameter

[Gao Xiang]

Hi Jingbo,

On 2024/1/2 23:10, Jingbo Xu wrote:
> Hi Chunhai,
> 
> Thanks for the commit.
> 
> On 1/2/24 11:01 PM, Chunhai Guo wrote:
>> Make erofs_err() and erofs_info() support NULL sb parameter for more
>> general usage.
>>
>> Suggested-by: Gao Xiang <xiang at kernel.org>
>> Signed-off-by: Chunhai Guo <guochunhai at vivo.com>
>> ---
>>   fs/erofs/super.c | 10 ++++++++--
>>   1 file changed, 8 insertions(+), 2 deletions(-)
>>
>> diff --git a/fs/erofs/super.c b/fs/erofs/super.c
>> index 3789d6224513..5f60f163bd56 100644
>> --- a/fs/erofs/super.c
>> +++ b/fs/erofs/super.c
>> @@ -27,7 +27,10 @@ void _erofs_err(struct super_block *sb, const char *func, const char *fmt, ...)
>>   	vaf.fmt = fmt;
>>   	vaf.va = &args;
>>   
>> -	pr_err("(device %s): %s: %pV", sb->s_id, func, &vaf);
>> +	if (sb)
>> +		pr_err("(device %s): %s: %pV", sb->s_id, func, &vaf);
>> +	else
>> +		pr_err("%s: %pV", func, &vaf);
>>   	va_end(args);
>>   }
>>   
>> @@ -41,7 +44,10 @@ void _erofs_info(struct super_block *sb, const char *func, const char *fmt, ...)
>>   	vaf.fmt = fmt;
>>   	vaf.va = &args;
>>   
>> -	pr_info("(device %s): %pV", sb->s_id, &vaf);
>> +	if (sb)
>> +		pr_info("(device %s): %pV", sb->s_id, &vaf);
>> +	else
>> +		pr_info("%pV", &vaf);
>>   	va_end(args);
>>   }
>>   
> 
> May I ask in which case the input sb parameter will be NULL?  In that
> case, why don't we call pr_err() or pr_info() directly?

That was my suggestion. erofs_err/info are widely used in the codebase
and they emit the final "\n" but pr_err/pr_info need to use "\n" in
contrast.

Combining these two usage might not quite good.  Does it sound good to
you?

Also, it is worth converting the only one to erofs_err now.
decompressor_deflate.c: pr_err("failed to allocate zlib workspace\n");

THNKS,
GAO XIANG