From b994ebdfbde87a61d9df0938b1b447a0819d47d8 Mon Sep 17 00:00:00 2001
From: Konrad Sztyber <konrad.sztyber@intel.com>
Date: Wed, 24 Aug 2022 09:28:25 +0200
Subject: [PATCH] sma: interface for querying QoS capabilities

Signed-off-by: Konrad Sztyber <konrad.sztyber@intel.com>
Change-Id: I6013205499c122cad95d807c84e609f188b4d2d2
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/14189
Tested-by: SPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: Tomasz Zawadzki <tomasz.zawadzki@intel.com>
Reviewed-by: Jim Harris <james.r.harris@intel.com>
---
 python/spdk/sma/proto/sma.proto | 42 ++++++++++++++++++++++++++++++++-
 1 file changed, 41 insertions(+), 1 deletion(-)

diff --git a/python/spdk/sma/proto/sma.proto b/python/spdk/sma/proto/sma.proto
index 7f1f04c07..abc427482 100644
--- a/python/spdk/sma/proto/sma.proto
+++ b/python/spdk/sma/proto/sma.proto
@@ -13,6 +13,14 @@ package sma;
 
 option go_package = "spdk.io/sma";
 
+// Enumeration defining types of devices
+enum DeviceType {
+  DEVICE_TYPE_INVALID = 0;
+  DEVICE_TYPE_NVME = 1;
+  DEVICE_TYPE_VIRTIO_BLK = 2;
+  DEVICE_TYPE_NVMF_TCP = 3;
+}
+
 // Volume's crypto parameters
 message VolumeCryptoParameters {
   // Key to be used for encryption
@@ -120,7 +128,8 @@ message SetQosRequest {
   // the QoS will be set up on the whole device (all volumes attached to that
   // device will share QoS settings).  Some device types might only support
   // configuring QoS on per-device (volume_id must be empty) or per-volume level
-  // (volume_id cannot be empty).
+  // (volume_id cannot be empty).  This information can be obtained by sending a
+  // GetQosCapabilities request.
   bytes volume_id = 2;
   // Maximum allowed IOPS/bandwidth
   QosLimit maximum = 3;
@@ -129,6 +138,34 @@ message SetQosRequest {
 // SetQos response
 message SetQosResponse {}
 
+// Get QoS capabilities request
+message GetQosCapabilitiesRequest {
+  // Type of a device to query for QoS capabilities
+  DeviceType device_type = 1;
+}
+
+// Get QoS capabilities response
+message GetQosCapabilitiesResponse {
+  message QosCapabilities {
+    // Read IOPS
+    bool rd_iops = 1;
+    // Write IOPS
+    bool wr_iops = 2;
+    // Read/write IOPS
+    bool rw_iops = 3;
+    // Read bandwidth
+    bool rd_bandwidth = 4;
+    // Write bandwidth
+    bool wr_bandwidth = 5;
+    // Read/write bandwidth
+    bool rw_bandwidth = 6;
+  }
+  // Device level maximum QoS limits
+  QosCapabilities max_device_caps = 1;
+  // Volume level maximum QoS limits
+  QosCapabilities max_volume_caps = 2;
+};
+
 // Storage Management Agent gRPC service definition
 service StorageManagementAgent {
   // Creates a new device.  A device is an entity that can be used to expose
@@ -151,4 +188,7 @@ service StorageManagementAgent {
   // Configures QoS on a device/volume
   rpc SetQos (SetQosRequest)
     returns (SetQosResponse) {}
+  // Returns QoS capabilities of a given device type
+  rpc GetQosCapabilities (GetQosCapabilitiesRequest)
+    returns (GetQosCapabilitiesResponse) {}
 }