[dm-devel] [PATCH 1/4] block: Enhance blk_revalidate_disk_zones()

[Damien Le Moal]

On 2019/10/24 16:08, Christoph Hellwig wrote:
>> diff --git a/block/blk-zoned.c b/block/blk-zoned.c
>> index 4bc5f260248a..293891b7068a 100644
>> --- a/block/blk-zoned.c
>> +++ b/block/blk-zoned.c
>> @@ -441,6 +441,57 @@ void blk_queue_free_zone_bitmaps(struct request_queue *q)
>>  	q->seq_zones_wlock = NULL;
>>  }
>>  
>> +/**
>> + * blk_check_zone - Check a zone information
>> + * @q:		request queue
>> + * @zone:	the zone to  check
>> + * @sector:	start sector of the zone
>> + *
>> + * Helper function to check zones of a zoned block device. Returns true if the
>> + * zone is correct and false if a problem is detected.
>> + */
>> +static bool blk_check_zone(struct gendisk *disk, struct blk_zone *zone,
>> +			   sector_t *sector)
> 
> Maybe call this blk_zone_valid?  Also in many places we don't really
> do the verbose kerneldoc comments with the duplicated parameter names
> for local functions, as the scripts only pick up non-stack ones anyway.
> 
>> +	/*
>> +	 * All zones must have the same size, with the exception on an eventual
>> +	 * smaller last zone.
>> +	 */
>> +	if (zone->start + zone_sectors < capacity &&
>> +	    zone->len != zone_sectors) {
>> +		pr_warn("%s: Invalid zone device with non constant zone size\n",
>> +			disk->disk_name);
>> +		return false;
>> +	}
> 
> I think we should also move the power of two zone size check here
> instead of leaving it in the driver.

We should not since the drivers calls blk_queue_chunk_sectors() first to
set the zone size and that function has a power of 2 check. So better
check that earlier than here.

-- 
Damien Le Moal
Western Digital Research