kernel/protocols: Add OCP to core query protocol

The query protocol is used to check the availability of a protocol at a
given version.

It should take into account every available protocol. Add the new OCP
protocol management.

Signed-off-by: Nicola Ramacciotti <niko.ramak@gmail.com>

Author: n-ramacciotti

kernel/src/protocols/core.rs

@@ -17,10 +17,15 @@ use crate::protocols::SVSM_UEFI_MM_PROTOCOL;
 use crate::protocols::apic::{APIC_PROTOCOL_VERSION_MAX, APIC_PROTOCOL_VERSION_MIN};
 use crate::protocols::attest::{ATTEST_PROTOCOL_VERSION_MAX, ATTEST_PROTOCOL_VERSION_MIN};
 use crate::protocols::errors::SvsmReqError;
+use crate::protocols::ocp::{
+    OBSERVABILITY_CONFIGURATION_PROTOCOL_VERSION_MAX,
+    OBSERVABILITY_CONFIGURATION_PROTOCOL_VERSION_MIN,
+};
 #[cfg(all(feature = "uefivars", not(test)))]
 use crate::protocols::uefivars::{UEFI_MM_PROTOCOL_VERSION_MAX, UEFI_MM_PROTOCOL_VERSION_MIN};
 use crate::protocols::{
     RequestParams, SVSM_APIC_PROTOCOL, SVSM_ATTEST_PROTOCOL, SVSM_CORE_PROTOCOL,
+    SVSM_OBSERVABILITY_CONFIGURATION_PROTOCOL,
 };
 #[cfg(all(feature = "vtpm", not(test)))]
 use crate::protocols::{
@@ -276,6 +281,11 @@ fn core_query_protocol(params: &mut RequestParams) -> Result<(), SvsmReqError> {
             UEFI_MM_PROTOCOL_VERSION_MIN,
             UEFI_MM_PROTOCOL_VERSION_MAX,
         ),
+        SVSM_OBSERVABILITY_CONFIGURATION_PROTOCOL => protocol_supported(
+            version,
+            OBSERVABILITY_CONFIGURATION_PROTOCOL_VERSION_MIN,
+            OBSERVABILITY_CONFIGURATION_PROTOCOL_VERSION_MAX,
+        ),
         _ => 0,
     };
 

kernel/src/protocols/ocp.rs

@@ -27,6 +27,10 @@ const SVSM_OCP_LIST: u32 = 0;
 const SVSM_OCP_READ: u32 = 1;
 const SVSM_OCP_WRITE: u32 = 2;
 
+// Min and Max supported protocol version
+pub const OBSERVABILITY_CONFIGURATION_PROTOCOL_VERSION_MIN: u32 = 1;
+pub const OBSERVABILITY_CONFIGURATION_PROTOCOL_VERSION_MAX: u32 = 1;
+
 #[bitfield(u32)]
 #[derive(IntoBytes, Immutable)]
 struct OcpSourceFlags {