Re: [PATCH v4]: ublk: Add UBLK_U_CMD_UPDATE_SIZE

[Jared Holzman <jholzman@nvidia.com>]

On 21/04/2025 5:51, Ming Lei wrote:
> On Sun, Apr 20, 2025 at 11:06:17AM +0300, Jared Holzman wrote:
>>
>>
>> On 18/04/2025 2:35, Ming Lei wrote:
>>> On Wed, Apr 16, 2025 at 01:07:47PM +0300, Jared Holzman wrote:
>>>> Currently ublk only allows the size of the ublkb block device to be
>>>> set via UBLK_CMD_SET_PARAMS before UBLK_CMD_START_DEV is triggered.
>>>>
>>>> This does not provide support for extendable user-space block devices
>>>> without having to stop and restart the underlying ublkb block device
>>>> causing IO interruption.
>>>>
>>>> This patch adds a new ublk command UBLK_U_CMD_UPDATE_SIZE to allow the
>>>> ublk block device to be resized on-the-fly.
>>>>
>>>> Feature flag UBLK_F_UPDATE_SIZE is also added to indicate support for this
>>>> command.
>>>>
>>>> Signed-off-by: Omri Mann <omri@nvidia.com>
>>>> ---
>>>>   drivers/block/ublk_drv.c      | 18 +++++++++++++++++-
>>>>   include/uapi/linux/ublk_cmd.h |  7 +++++++
>>>>   2 files changed, 24 insertions(+), 1 deletion(-)
>>>>
>>>> diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
>>>> index cdb1543fa4a9..128f094efbad 100644
>>>> --- a/drivers/block/ublk_drv.c
>>>> +++ b/drivers/block/ublk_drv.c
>>>> @@ -64,7 +64,8 @@
>>>>           | UBLK_F_CMD_IOCTL_ENCODE \
>>>>           | UBLK_F_USER_COPY \
>>>>           | UBLK_F_ZONED \
>>>> -        | UBLK_F_USER_RECOVERY_FAIL_IO)
>>>> +        | UBLK_F_USER_RECOVERY_FAIL_IO \
>>>> +        | UBLK_F_UPDATE_SIZE)
>>>>
>>>>   #define UBLK_F_ALL_RECOVERY_FLAGS (UBLK_F_USER_RECOVERY \
>>>>           | UBLK_F_USER_RECOVERY_REISSUE \
>>>> @@ -3067,6 +3068,16 @@ static int ublk_ctrl_get_features(const struct
>>>> ublksrv_ctrl_cmd *header)
>>>
>>> I try to apply this patch downloaded from both lore or patchwork, and 'git
>>> am' always complains the patch is broken:
>>
>> I think this is because of my workflow. I cannot send email outside of our
>> network using git send-mail so I've been copy-pasting the patch into
>> Thunderbird.
> 
> oops, copy-paste usually breaks patch style, probably `xclip` can help you
> if copy-paste can't be avoided.

Apparently Thunderbird also breaks patch style by default. I had to change some settings.

> 
> You probably need to find one email client to support importing patch plain
> text from file or sending patch directly, such as mutt/msmtp,...

Should be good now. Please see v6 of the patch I just sent. I already tried downloading and applying it myself and it works.

Apologies for the noise.


> 
> Thanks,
> Ming
>