Re: [PATCH v5 12/16] md/raid5: support config stripe_size by sysfs entry

[Yufen Yu <yuyufen@huawei.com>]

On 2020/7/3 6:38, Song Liu wrote:
> On Thu, Jul 2, 2020 at 5:05 AM Yufen Yu <yuyufen@huawei.com> wrote:
>>
>> After this patch, we can adjust stripe_size by writing value into sysfs
>> entry, likely, set stripe_size as 16KB:
>>
>>            echo 16384 > /sys/block/md1/md/stripe_size
>>
>> Show current stripe_size value:
>>
>>            cat /sys/block/md1/md/stripe_size
>>
>> stripe_size should not be bigger than PAGE_SIZE, and it requires to be
>> multiple of 4096.
> 
> I think we can just merge 02/16 into this one.
> 
>>
>> Signed-off-by: Yufen Yu <yuyufen@huawei.com>
>> ---
>>   drivers/md/raid5.c | 69 +++++++++++++++++++++++++++++++++++++++++++++-
>>   1 file changed, 68 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
>> index f0fd01d9122e..a3376a4e4e5c 100644
>> --- a/drivers/md/raid5.c
>> +++ b/drivers/md/raid5.c
>> @@ -6715,7 +6715,74 @@ raid5_show_stripe_size(struct mddev  *mddev, char *page)
>>   static ssize_t
>>   raid5_store_stripe_size(struct mddev  *mddev, const char *page, size_t len)
>>   {
>> -       return -EINVAL;
>> +       struct r5conf *conf = mddev->private;
> 
> We need mddev_lock(mddev) before accessing mddev->private.
>

Thanks to point this bug. I will fix it.

Thanks,
Yufen