Implement bulk of UEFI protocol needed by linux kernel

.gitignore

@@ -17,3 +17,5 @@ tagit
 TAGS
 tags
 toolchain
+.cache
+vmlinux

external/lib/heap/dlmalloc/rules.mk

@@ -2,6 +2,15 @@ LOCAL_DIR := $(GET_LOCAL_DIR)
 
 MODULE := $(LOCAL_DIR)
 
+# MSPACE=1 enables mspace_malloc and other mspace_* routines.
+# They allow users to use preallocated memory for heap allocations
+# It's common for VM applications to preallocate backing memory for
+# the guest, then free the entire backing memory at once after guest
+# exits. This ensures no memory leak even if guest doesn't free its
+# memory properly. Or hypervisor may wish that the guest memory
+# are all contigous, etc.
+MODULE_DEFINES=MSPACES=1
+
 MODULE_SRCS += \
 	$(LOCAL_DIR)/dlmalloc.c
 

kernel/include/kernel/vm.h

@@ -46,6 +46,7 @@ __BEGIN_CDECLS
 
 #define PAGE_ALIGN(x) ALIGN(x, PAGE_SIZE)
 #define IS_PAGE_ALIGNED(x) IS_ALIGNED(x, PAGE_SIZE)
+struct list_node *get_arena_list(void);
 
 struct mmu_initial_mapping {
     paddr_t phys;
@@ -259,7 +260,7 @@ void vmm_context_switch(vmm_aspace_t *oldspace, vmm_aspace_t *newaspace);
 
 /* set the current user aspace as active on the current thread.
    NULL is a valid argument, which unmaps the current user address space */
-void vmm_set_active_aspace(vmm_aspace_t *aspace);
+vmm_aspace_t* vmm_set_active_aspace(vmm_aspace_t *aspace);
 
 __END_CDECLS
 

kernel/vm/pmm.c

@@ -34,6 +34,8 @@ static mutex_t lock = MUTEX_INITIAL_VALUE(lock);
 #define ADDRESS_IN_ARENA(address, arena) \
     ((address) >= (arena)->base && (address) <= (arena)->base + (arena)->size - 1)
 
+struct list_node *get_arena_list() { return &arena_list; }
+
 static inline bool page_is_free(const vm_page_t *page) {
     return !(page->flags & VM_PAGE_FLAG_NONFREE);
 }

kernel/vm/vmm.c

@@ -12,6 +12,7 @@
 #include <lk/err.h>
 #include <lk/trace.h>
 #include <string.h>
+#include "kernel/thread.h"
 #include "vm_priv.h"
 
 #define LOCAL_TRACE 0
@@ -751,21 +752,24 @@ void vmm_context_switch(vmm_aspace_t *oldspace, vmm_aspace_t *newaspace) {
     arch_mmu_context_switch(newaspace ? &newaspace->arch_aspace : NULL);
 }
 
-void vmm_set_active_aspace(vmm_aspace_t *aspace) {
+vmm_aspace_t* vmm_set_active_aspace(vmm_aspace_t *aspace) {
     LTRACEF("aspace %p\n", aspace);
 
     thread_t *t = get_current_thread();
     DEBUG_ASSERT(t);
 
     if (aspace == t->aspace)
-        return;
+        return aspace;
 
     /* grab the thread lock and switch to the new address space */
     THREAD_LOCK(state);
     vmm_aspace_t *old = t->aspace;
-    t->aspace = aspace;
-    vmm_context_switch(old, t->aspace);
+    if (old != aspace) {
+        t->aspace = aspace;
+        vmm_context_switch(old, t->aspace);
+    }
     THREAD_UNLOCK(state);
+    return old;
 }
 
 static void dump_region(const vmm_region_t *r) {

lib/uefi/README.md

@@ -4,11 +4,13 @@
 make qemu-virt-arm64-test
 ```
 
+Note, this may fail if your system does not have `aarch64-elf-gcc` installed. To address, download from [here](https://newos.org/toolchains/aarch64-elf-14.2.0-Linux-x86_64.tar.xz), unzip, and add the extracted dir to PATH.
+
 ## Run
 
 ```
 qemu-system-aarch64 -cpu max -m 512 -smp 1 -machine virt,highmem=off \
-	-kernel qemu-virt-arm64-test/lk.elf \
+	-kernel build-qemu-virt-arm64-test/lk.elf \
 	-net none -nographic \
 	-drive if=none,file=lib/uefi/helloworld_aa64.efi,id=blk,format=raw \
 	-device virtio-blk-device,drive=blk