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Date:   Fri, 20 May 2022 11:09:23 +0200
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Subject: Re: [PATCH v4 08/13] btrfs:zoned: make sb for npo2 zone devices
 align with sb log offsets
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To:     Naohiro Aota <Naohiro.Aota@wdc.com>
CC:     "axboe@kernel.dk" <axboe@kernel.dk>,
        "damien.lemoal@opensource.wdc.com" <damien.lemoal@opensource.wdc.com>,
        "pankydev8@gmail.com" <pankydev8@gmail.com>,
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        "linux-nvme@lists.infradead.org" <linux-nvme@lists.infradead.org>,
        "linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>,
        "linux-btrfs@vger.kernel.org" <linux-btrfs@vger.kernel.org>,
        "jiangbo.365@bytedance.com" <jiangbo.365@bytedance.com>,
        "linux-block@vger.kernel.org" <linux-block@vger.kernel.org>,
        "gost.dev@samsung.com" <gost.dev@samsung.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
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From:   Pankaj Raghav <p.raghav@samsung.com>
In-Reply-To: <20220519075926.6h4ka3qbo3vv26ve@naota-xeon>
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References: <20220516165416.171196-1-p.raghav@samsung.com>
        <CGME20220516165429eucas1p272c8b4325a488675f08f2d7016aa6230@eucas1p2.samsung.com>
        <20220516165416.171196-9-p.raghav@samsung.com>
        <20220519075926.6h4ka3qbo3vv26ve@naota-xeon>
Precedence: bulk

On 5/19/22 09:59, Naohiro Aota wrote:
>> +
>>  static int sb_log_location(struct block_device *bdev, struct blk_zone *zones,
>> -			   int rw, u64 *bytenr_ret)
>> +			   int rw, int mirror, u64 *bytenr_ret)
>>  {
>>  	u64 wp;
>>  	int ret;
>> +	bool zones_empty = false;
>>  
>>  	if (zones[0].type == BLK_ZONE_TYPE_CONVENTIONAL) {
>>  		*bytenr_ret = zones[0].start << SECTOR_SHIFT;
>> @@ -775,13 +808,31 @@ static int sb_log_location(struct block_device *bdev, struct blk_zone *zones,
>>  	if (ret != -ENOENT && ret < 0)
>>  		return ret;
>>  
>> +	if (ret == -ENOENT)
>> +		zones_empty = true;
>> +
> 
> I think, we don't need this. We need to issue the zeroout when
> zones[0]->cond == BLK_ZONE_COND_EMPTY && !is_power_of_2(...) after sending
> ZONE_RESET if necessary. No?
> 
Yeah. I added this extra check to cover all the cases possible. But you
are right that it is enough to issue zeroout only for this condition:
zones[0]->cond == BLK_ZONE_COND_EMPTY && !is_power_of_2(...) as both the
zones empty is not likely to happen.
>>  	if (rw == WRITE) {
>>  		struct blk_zone *reset = NULL;
>> +		bool is_sb_offset_write_req = false;
>> +		u32 reset_zone_nr = -1;
>>  
>> -		if (wp == zones[0].start << SECTOR_SHIFT)
>> +		if (wp == zones[0].start << SECTOR_SHIFT) {
>>  			reset = &zones[0];
>> -		else if (wp == zones[1].start << SECTOR_SHIFT)
>> +			reset_zone_nr = 0;