Modify wording based on comments on July 24th

csi.proto

@@ -383,13 +383,13 @@ message CreateVolumeRequest {
   // choose where the provisioned volume is accessible from.
   TopologyRequirement accessibility_requirements = 7;
 
-  // Plugin specific mutable parameters passed in as opaque key-value
-  // pairs. This field is OPTIONAL. The Plugin is responsible for 
-  // parsing and validating these parameters. COs will treat these 
-  // as opaque. Plugins MUST treat these as if they take precedence 
-  // over the parameters field.
-  // COs SHALL NOT provide any values in mutable_parameters if the
-  // capability is not enabled.
+  // Plugin specific parameters to apply, passed in as opaque
+  // key-value pairs. This field is OPTIONAL. The Plugin is
+  // responsible for  parsing and validating these parameters. 
+  // COs will treat these as opaque. Plugins MUST treat these 
+  // as if they take precedence over the parameters field.
+  // This field SHALL NOT be specified unless the SP has the
+  // MODIFY_VOLUME plugin capability.
   map<string, string> mutable_parameters = 8 [(alpha_field) = true];
 }
 
@@ -1010,12 +1010,12 @@ message ControllerModifyVolumeRequest {
   map<string, string> secrets = 2 [(csi_secret) = true];
 
   // Plugin specific parameters to apply, passed in as opaque key-value
-  // pairs. This field is OPTIONAL. The Plugin is responsible for
+  // pairs. This field is REQUIRED. The Plugin is responsible for
   // parsing and validating these parameters. COs will treat these
-  // as opaque. COs MUST specify the intended value of every mutable
-  // parameter. Absent keys that were previously assigned a value MUST
-  // be interpreted as a deletion of the key from the set of mutable
-  // parameters.
+  // as opaque. The CO SHOULD specify the intended values of all mutable
+  // parameters it intends to modify. SPs MUST NOT modify volumes based
+  // on the absence of keys, only keys that are specified should result
+  // in modifications to the volume.
   map<string, string> mutable_parameters = 3;
 }
 

spec.md

@@ -854,13 +854,13 @@ message CreateVolumeRequest {
   // choose where the provisioned volume is accessible from.
   TopologyRequirement accessibility_requirements = 7;
 
-  // Plugin specific mutable parameters passed in as opaque key-value
-  // pairs. This field is OPTIONAL. The Plugin is responsible for 
-  // parsing and validating these parameters. COs will treat these 
-  // as opaque. Plugins MUST treat these as if they take precedence 
-  // over the parameters field.
-  // COs SHALL NOT provide any values in mutable_parameters if the
-  // capability is not enabled.
+  // Plugin specific parameters to apply, passed in as opaque
+  // key-value pairs. This field is OPTIONAL. The Plugin is
+  // responsible for  parsing and validating these parameters. 
+  // COs will treat these as opaque. Plugins MUST treat these 
+  // as if they take precedence over the parameters field.
+  // This field SHALL NOT be specified unless the SP has the
+  // MODIFY_VOLUME plugin capability.
   map<string, string> mutable_parameters = 8 [(alpha_field) = true];
 }
 
@@ -1668,12 +1668,12 @@ message ControllerModifyVolumeRequest {
   map<string, string> secrets = 2 [(csi_secret) = true];
 
   // Plugin specific parameters to apply, passed in as opaque key-value
-  // pairs. This field is OPTIONAL. The Plugin is responsible for
+  // pairs. This field is REQUIRED. The Plugin is responsible for
   // parsing and validating these parameters. COs will treat these
-  // as opaque. COs MUST specify the intended value of every mutable
-  // parameter. Absent keys that were previously assigned a value MUST
-  // be interpreted as a deletion of the key from the set of mutable
-  // parameters.
+  // as opaque. The CO SHOULD specify the intended values of all mutable
+  // parameters it intends to modify. SPs MUST NOT modify volumes based
+  // on the absence of keys, only keys that are specified should result
+  // in modifications to the volume.
   map<string, string> mutable_parameters = 3;
 }