From mboxrd@z Thu Jan  1 00:00:00 1970
From: Bart Van Assche <bvanassche@acm.org>
Subject: Re: [PATCH 1/4] block: add zone open, close and finish support
Date: Tue, 25 Jun 2019 08:55:56 -0700
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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 
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().
- Add open/close/flush zone support be added in blk_partition_remap().

Thanks,

Bart.