feat(slave-side-prot): add device access control enable function

Each architecture needs to implement their access control function.
This function is called during the dev init for vms, and is executed instead
of the original memory mapping.

Signed-off-by: Miguel Silva <[email protected]>

Author: miguelafsilva5

src/core/inc/vm.h

@@ -183,5 +183,6 @@ unsigned long vcpu_readpc(struct vcpu* vcpu);
 void vcpu_writepc(struct vcpu* vcpu, unsigned long pc);
 void vcpu_arch_reset(struct vcpu* vcpu, vaddr_t entry);
 bool vcpu_arch_is_on(struct vcpu* vcpu);
+void vm_arch_allow_mmio_access(struct vm_dev_region* dev);
 
 #endif /* __VM_H__ */

src/core/vm.c

@@ -20,8 +20,6 @@ static void vm_master_init(struct vm* vm, const struct vm_config* vm_config, vmi
     vm->lock = SPINLOCK_INITVAL;
 
     cpu_sync_init(&vm->sync, vm->cpu_num);
-
-    vm_mem_prot_init(vm, vm_config);
 }
 
 static void vm_cpu_init(struct vm* vm)
@@ -210,9 +208,10 @@ static void vm_init_dev(struct vm* vm, const struct vm_config* vm_config)
     for (size_t i = 0; i < vm_config->platform.dev_num; i++) {
         struct vm_dev_region* dev = &vm_config->platform.devs[i];
 
-        size_t n = ALIGN(dev->size, PAGE_SIZE) / PAGE_SIZE;
-
-        if (dev->va != INVALID_VA) {
+        if (DEFINED(MMIO_SLAVE_SIDE_PROT)) {
+            vm_arch_allow_mmio_access(dev);
+        } else if (dev->va != INVALID_VA) {
+            size_t n = ALIGN(dev->size, PAGE_SIZE) / PAGE_SIZE;
             mem_alloc_map_dev(&vm->as, SEC_VM_ANY, (vaddr_t)dev->va, dev->pa, n);
         }
 
@@ -319,6 +318,12 @@ struct vm* vm_init(struct vm_allocation* vm_alloc, const struct vm_config* vm_co
 
     cpu_sync_barrier(&vm->sync);
 
+    if (master) {
+        vm_mem_prot_init(vm, vm_config);
+    }
+
+    cpu_sync_barrier(&vm->sync);
+
     /**
      * Perform architecture dependent initializations. This includes, for example, setting the page
      * table pointer and other virtualization extensions specifics.
@@ -422,3 +427,10 @@ void vcpu_run(struct vcpu* vcpu)
         cpu_powerdown();
     }
 }
+
+__attribute__((weak)) void vm_arch_allow_mmio_access(struct vm_dev_region* dev)
+{
+    UNUSED_ARG(dev);
+    ERROR("vm_arch_allow_mmio_access must be implemented by the arch!")
+    return;
+}