[PATCH v15 1/7] docs/qcow2: add the zoned format feature

[Niklas Cassel <cassel@kernel.org>]

From: Sam Li <faithilikerun@gmail.com>

Add the specs for the zoned format feature of the qcow2 driver.
The qcow2 file then can emulate real zoned devices, either passed
through by virtio-blk device or NVMe ZNS drive to the guest
given zoned information.

Signed-off-by: Sam Li <faithilikerun@gmail.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Niklas Cassel <cassel@kernel.org>
---
Changes by Niklas Cassel:
- do not document a zone append size limit, which the driver no longer
  stores in the image
---
 docs/system/qemu-block-drivers.rst.inc | 44 ++++++++++++++++++++++++++
 1 file changed, 44 insertions(+)

diff --git a/docs/system/qemu-block-drivers.rst.inc b/docs/system/qemu-block-drivers.rst.inc
index 675daa72f9..70b9b8d1b4 100644
--- a/docs/system/qemu-block-drivers.rst.inc
+++ b/docs/system/qemu-block-drivers.rst.inc
@@ -172,6 +172,50 @@ This section describes each format and the options that are supported for it.
     filename`` to check if the NOCOW flag is set or not (Capital 'C' is
     NOCOW flag).
 
+  .. option:: zone.mode
+
+    If this is set to ``host-managed``, the image is an emulated zoned
+    block device. This option is only valid for emulated zoned device files.
+
+  .. option:: zone.size
+
+    The size of a zone in bytes. The device is divided into zones of this
+    size with the exception of the last zone, which may be smaller.
+    Defaults to ``256 MiB``.
+
+  .. option:: zone.capacity
+
+    The initial capacity value, in bytes, for all zones. The capacity must
+    be less than or equal to zone size. If the last zone is smaller, then
+    its capacity is capped. Defaults to ``zone.size``.
+
+    The zone capacity is per zone and may be different between zones in real
+    devices. QCow2 sets all zones to the same capacity.
+
+  .. option:: zone.conventional_zones
+
+    The number of conventional zones of the zoned device. Defaults to ``0``
+    (all zones are sequential-write-required).
+
+  .. option:: zone.max_active_zones
+
+    The maximum allowed active zones (zones in the implicit open, explicit
+    open, or closed state).
+
+    The max active zones must be less or equal to the number of SWR
+    (sequential write required) zones of the device. Defaults to ``0``,
+    meaning no limit.
+
+  .. option:: zone.max_open_zones
+
+    The maximum allowed open zones (zones in the implicit open or explicit
+    open state). The max open zones must not be larger than the max active
+    zones. Defaults to ``zone.max_active_zones`` if that is set, otherwise
+    ``0`` (no limit).
+
+    If the limits of open zones or active zones are equal to the number of
+    SWR zones, then it is the same as having no limits.
+
 .. program:: image-formats
 .. option:: qed
 
-- 
2.56.0