LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Niklas Cassel <Niklas.Cassel@wdc.com>
To: Keith Busch <kbusch@kernel.org>, Jens Axboe <axboe@fb.com>,
	Christoph Hellwig <hch@lst.de>, Sagi Grimberg <sagi@grimberg.me>
Cc: "damien.lemoal@opensource.wdc.com"
	<damien.lemoal@opensource.wdc.com>,
	Niklas Cassel <Niklas.Cassel@wdc.com>,
	"linux-nvme@lists.infradead.org" <linux-nvme@lists.infradead.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: [PATCH v2] nvme: report write pointer for a full zone as zone start + zone len
Date: Fri, 26 Nov 2021 10:42:44 +0000	[thread overview]
Message-ID: <20211126104157.227400-1-Niklas.Cassel@wdc.com> (raw)

From: Niklas Cassel <niklas.cassel@wdc.com>

The write pointer in NVMe ZNS is invalid for a zone in zone state full.
The same also holds true for ZAC/ZBC.

The current behavior for NVMe is to simply propagate the wp reported by
the drive, even for full zones. Since the wp is invalid for a full zone,
the wp reported by the drive may be any value.

The way that the sd_zbc driver handles a full zone is to always report
the wp as zone start + zone len, regardless of what the drive reported.
null_blk also follows this convention.

Do the same for NVMe, so that a BLKREPORTZONE ioctl reports the write
pointer for a full zone in a consistent way, regardless of the interface
of the underlying zoned block device.

blkzone report before patch:
start: 0x000040000, len 0x040000, cap 0x03e000, wptr 0xfffffffffffbfff8
reset:0 non-seq:0, zcond:14(fu) [type: 2(SEQ_WRITE_REQUIRED)]

blkzone report after patch:
start: 0x000040000, len 0x040000, cap 0x03e000, wptr 0x040000 reset:0
non-seq:0, zcond:14(fu) [type: 2(SEQ_WRITE_REQUIRED)]

Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
---
Changes since v1:
- Minor commit message rewording.
- Use if/else instead of setting wp unconditionally and then
  conditionally updating it.

 drivers/nvme/host/zns.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/nvme/host/zns.c b/drivers/nvme/host/zns.c
index bfc259e0d7b8..9f81beb4df4e 100644
--- a/drivers/nvme/host/zns.c
+++ b/drivers/nvme/host/zns.c
@@ -166,7 +166,10 @@ static int nvme_zone_parse_entry(struct nvme_ns *ns,
 	zone.len = ns->zsze;
 	zone.capacity = nvme_lba_to_sect(ns, le64_to_cpu(entry->zcap));
 	zone.start = nvme_lba_to_sect(ns, le64_to_cpu(entry->zslba));
-	zone.wp = nvme_lba_to_sect(ns, le64_to_cpu(entry->wp));
+	if (zone.cond == BLK_ZONE_COND_FULL)
+		zone.wp = zone.start + zone.len;
+	else
+		zone.wp = nvme_lba_to_sect(ns, le64_to_cpu(entry->wp));
 
 	return cb(&zone, idx, data);
 }
-- 
2.33.1

             reply	other threads:[~2021-11-26 10:44 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-11-26 10:42 Niklas Cassel [this message]
2021-11-27  1:08 ` Damien Le Moal
2021-12-02 13:35 ` Johannes Thumshirn
2021-12-03 16:00 ` Keith Busch
2021-12-06  7:54 ` Christoph Hellwig

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20211126104157.227400-1-Niklas.Cassel@wdc.com \
    --to=niklas.cassel@wdc.com \
    --cc=axboe@fb.com \
    --cc=damien.lemoal@opensource.wdc.com \
    --cc=hch@lst.de \
    --cc=kbusch@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-nvme@lists.infradead.org \
    --cc=sagi@grimberg.me \
    --subject='Re: [PATCH v2] nvme: report write pointer for a full zone as zone start + zone len' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).