Re: [PATCH 1/4] block: add zone open, close and finish support

[Damien Le Moal]

On 2019/06/26 1:51, Chaitanya Kulkarni wrote:
> On 06/25/2019 08:56 AM, Bart Van Assche wrote:
>> On 6/25/19 3:35 AM, Matias Bjørling wrote:
>>> On 6/25/19 12:27 AM, Chaitanya Kulkarni wrote:
>>>> On 6/24/19 12:43 PM, Bart Van Assche wrote:
>>>>> static inline bool op_is_write(unsigned int op)
>>>>> {
>>>>>      return (op & 1);
>>>>> }
>>>>>
>>>>
>>>
>>> The zone mgmt commands are neither write nor reads commands. I guess,
>>> one could characterize them as write commands, but they don't write any
>>> data, they update a state of a zone on a drive. One should keep it as
>>> is? and make sure the zone mgmt commands don't get categorized as either
>>> read/write.
>>
>> Since the open, close and finish operations support modifying zone data
>> I propose to characterize these as write commands. How about the
>> following additional changes:
>> - Make bio_check_ro() refuse open/close/flush/reset zone operations for
>                                           ^
> Since finish also listed above which supports modifying data do we need 
> to add finish here with flush in above line ?

There is no "zone flush" operation. I guess Bart made a typo here and meant
"finish". "flush" on a zoned disk is not different from regular disks.

> 
>> read-only partitions (see also commit a32e236eb93e ("Partially revert
>> "block: fail op_is_write() requests to read-only partitions"") # v4.18).
>> - In submit_bio(), change op_is_write(bio_op(bio)) ? "WRITE" : "READ"
>> into something that uses blk_op_str().
> Good idea, I've a patch for blk_op_str() and debugfs just waiting for 
> this to merge. Does it make sense to add that patch in this series ?
>> - Add open/close/flush zone support be added in blk_partition_remap().
> same here for finish ?
>>
>> Thanks,
>>
>> Bart.
>>
> 
> 


-- 
Damien Le Moal
Western Digital Research