From c2dfe1736352c164df44211e1446669aa6594710 Mon Sep 17 00:00:00 2001
From: Drew Galbraith <dgalbraith33@gmail.com>
Date: Wed, 21 Jun 2023 18:46:06 -0700
Subject: [PATCH] [zion] Use ErrorOr in PciConfiguration

---
 lib/glacier/status/error_or.h  | 2 +-
 zion/boot/acpi.cpp             | 6 ++----
 zion/boot/acpi.h               | 7 ++++++-
 zion/syscall/memory_object.cpp | 8 ++++----
 4 files changed, 13 insertions(+), 10 deletions(-)

diff --git a/lib/glacier/status/error_or.h b/lib/glacier/status/error_or.h
index 755def3..38c00c8 100644
--- a/lib/glacier/status/error_or.h
+++ b/lib/glacier/status/error_or.h
@@ -12,7 +12,7 @@ class ErrorOr {
   ErrorOr(ErrorOr&&) = delete;
 
   ErrorOr(ErrorCode code) : error_(code), ok_(false) {}
-  ErrorOr(T obj) : obj_(obj), ok_(true) {}
+  ErrorOr(const T& obj) : obj_(obj), ok_(true) {}
   ErrorOr(T&& obj) : obj_(obj), ok_(true) {}
 
   bool ok() { return ok_; }
diff --git a/zion/boot/acpi.cpp b/zion/boot/acpi.cpp
index eb6fc53..9c450db 100644
--- a/zion/boot/acpi.cpp
+++ b/zion/boot/acpi.cpp
@@ -255,12 +255,10 @@ void ProbeRsdp() {
 #endif
 }
 
-z_err_t GetPciExtendedConfiguration(uint64_t* base, uint64_t* offset) {
+glcr::ErrorOr<PcieConfiguration> GetPciExtendedConfiguration() {
   if (gPcieEcSize == 0) {
     return glcr::NOT_FOUND;
   }
 
-  *base = gPcieEcBase;
-  *offset = gPcieEcSize;
-  return glcr::OK;
+  return PcieConfiguration{gPcieEcBase, gPcieEcSize};
 }
diff --git a/zion/boot/acpi.h b/zion/boot/acpi.h
index c151ed0..1216540 100644
--- a/zion/boot/acpi.h
+++ b/zion/boot/acpi.h
@@ -1,9 +1,14 @@
 #pragma once
 
+#include <glacier/status/error_or.h>
 #include <stdint.h>
 
 #include "include/ztypes.h"
 
 void ProbeRsdp();
 
-z_err_t GetPciExtendedConfiguration(uint64_t* base, uint64_t* offset);
+struct PcieConfiguration {
+  uint64_t base;
+  uint64_t offset;
+};
+glcr::ErrorOr<PcieConfiguration> GetPciExtendedConfiguration();
diff --git a/zion/syscall/memory_object.cpp b/zion/syscall/memory_object.cpp
index d9bba0a..a17ef00 100644
--- a/zion/syscall/memory_object.cpp
+++ b/zion/syscall/memory_object.cpp
@@ -32,11 +32,11 @@ z_err_t MemoryObjectCreateContiguous(ZMemoryObjectCreateContiguousReq* req) {
 
 z_err_t TempPcieConfigObjectCreate(ZTempPcieConfigObjectCreateReq* req) {
   auto& curr_proc = gScheduler->CurrentProcess();
-  uint64_t pci_base, pci_size;
-  RET_ERR(GetPciExtendedConfiguration(&pci_base, &pci_size));
-  auto vmmo_ref = glcr::MakeRefCounted<FixedMemoryObject>(pci_base, pci_size);
+  ASSIGN_OR_RETURN(PcieConfiguration config, GetPciExtendedConfiguration());
+  auto vmmo_ref =
+      glcr::MakeRefCounted<FixedMemoryObject>(config.base, config.offset);
   *req->vmmo_cap = curr_proc.AddNewCapability(
       StaticCastRefPtr<MemoryObject>(vmmo_ref), ZC_WRITE);
-  *req->vmmo_size = pci_size;
+  *req->vmmo_size = config.offset;
   return glcr::OK;
 }