[v2,14/15] docs: Add documentation for SR-IOV and Virtualization Enhancements

Commit Message

Łukasz Gieryk Nov. 16, 2021, 3:34 p.m. UTC

From: Lukasz Maniak <[e-mail]>

Signed-off-by: Lukasz Maniak <[e-mail]>
---
 docs/system/devices/nvme.rst | 35 +++++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)

Patch

diff --git a/docs/system/devices/nvme.rst b/docs/system/devices/nvme.rst
index bff72d1c24..29fe2565b5 100644
--- a/docs/system/devices/nvme.rst
+++ b/docs/system/devices/nvme.rst
@@ -235,3 +235,38 @@  The virtual namespace device supports DIF- and DIX-based protection information
   to ``1`` to transfer protection information as the first eight bytes of
   metadata. Otherwise, the protection information is transferred as the last
   eight bytes.
+
+Virtualization Enhancements and SR-IOV
+--------------------------------------
+
+The ``nvme`` device supports Single Root I/O Virtualization and Sharing
+along with Virtualization Enhancements. The controller has to be linked to
+an NVM Subsystem device (``nvme-subsys``) for use with SR-IOV.
+
+A number of parameters are present:
+
+``sriov_max_vfs`` (default: ``0``)
+  Indicates the maximum number of PCIe virtual functions supported
+  by the controller. Specifying a non-zero value enables reporting of both
+  SR-IOV and ARI (Alternative Routing-ID Interpretation) capabilities
+  by the NVMe device. Virtual function controllers will not report SR-IOV.
+
+``sriov_vq_flexible``
+  Indicates the total number of flexible queue resources assignable to all
+  the secondary controllers. Implicitly sets the number of PF-private
+  resources to (max_ioqpairs - sriov_vq_flexible).
+
+``sriov_vi_flexible``
+  Indicates the total number of flexible interrupt resources assignable to
+  all the secondary controllers. Implicitly sets the number of PF-private
+  resources to (msix_qsize - sriov_vi_flexible).
+
+``sriov_max_vi_per_vf``
+  Indicates the maximum number of virtual interrupt resources assignable
+  to a secondary controller. The default 0 resolves to the number of private
+  interrupt resources configured for PF.
+
+``sriov_max_vq_per_vf``
+  Indicates the maximum number of virtual queue resources assignable to
+  a secondary controller. The default 0 resolves to the number of private
+  queue resources configured for PF.