Documentation: ABI: stable: document the zoned_qd1_writes attribute

Update the documentation file Documentation/ABI/stable/sysfs-block to
describe the zoned_qd1_writes sysfs queue attribute file.

Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/Documentation/ABI/stable/sysfs-block b/Documentation/ABI/stable/sysfs-block
index 09a9d4aca0fd550c0b7c5f9293db146a45dc2b06..900b3fc4c72d0715f10a89c7d1c001d8f9a0917c 100644 (file)
--- a/Documentation/ABI/stable/sysfs-block
+++ b/Documentation/ABI/stable/sysfs-block
@@ -886,6 +886,21 @@ Description:
                zone commands, they will be treated as regular block devices and
                zoned will report "none".
 
+What:          /sys/block/<disk>/queue/zoned_qd1_writes
+Date:          January 2026
+Contact:       Damien Le Moal <dlemoal@kernel.org>
+Description:
+               [RW] zoned_qd1_writes indicates if write operations to a zoned
+               block device are being handled using a single issuer context (a
+               kernel thread) operating at a maximum queue depth of 1. This
+               attribute is visible only for zoned block devices. The default
+               value for zoned block devices that are not rotational devices
+               (e.g. ZNS SSDs or zoned UFS devices) is 0. For rotational zoned
+               block devices (e.g. SMR HDDs) the default value is 1. Since
+               this default may not be appropriate for some devices, e.g.
+               remotely connected devices over high latency networks, the user
+               can disable this feature by setting this attribute to 0.
+
 
 What:          /sys/block/<disk>/hidden
 Date:          March 2023