From e47c0cc9294b7659e62ae05115a403458d93ab50 Mon Sep 17 00:00:00 2001
From: tkchia <tkchia@users.noreply.github.com>
Date: Mon, 12 Jun 2023 01:32:39 +0800
Subject: [PATCH] [metal] Clean up code for getting pointer to `struct mman`
 (#828)

Co-authored-by: tkchia <tkchia-cosmo@gmx.com>
---
 libc/calls/munmap-metal.c     | 3 +--
 libc/intrin/directmap-metal.c | 2 +-
 libc/runtime/efimain.greg.c   | 2 +-
 libc/runtime/pc.internal.h    | 3 +++
 libc/vga/vga-init.greg.c      | 4 ++--
 5 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/libc/calls/munmap-metal.c b/libc/calls/munmap-metal.c
index 3b089e651..b4d69e11a 100644
--- a/libc/calls/munmap-metal.c
+++ b/libc/calls/munmap-metal.c
@@ -23,9 +23,8 @@
 noasan int sys_munmap_metal(void *addr, size_t size) {
   size_t i;
   uint64_t *e, paddr;
-  struct mman *mm;
+  struct mman *mm = __get_mm();
   uint64_t *pml4t = __get_pml4t();
-  mm = (struct mman *)(BANE + 0x0500);
   for (i = 0; i < size; i += 4096) {
     e = __get_virtual(mm, pml4t, (uint64_t)addr + i, false);
     if (e) {
diff --git a/libc/intrin/directmap-metal.c b/libc/intrin/directmap-metal.c
index 116176675..d6b82395c 100644
--- a/libc/intrin/directmap-metal.c
+++ b/libc/intrin/directmap-metal.c
@@ -46,7 +46,7 @@ noasan struct DirectMap sys_mmap_metal(void *vaddr, size_t size, int prot,
   struct mman *mm;
   struct DirectMap res;
   uint64_t addr, faddr = 0, page, e, *pte, *fdpte, *pml4t;
-  mm = (struct mman *)(BANE + 0x0500);
+  mm = __get_mm();
   pml4t = __get_pml4t();
   size = ROUNDUP(size, 4096);
   addr = (uint64_t)vaddr;
diff --git a/libc/runtime/efimain.greg.c b/libc/runtime/efimain.greg.c
index d04645221..777f6eca8 100644
--- a/libc/runtime/efimain.greg.c
+++ b/libc/runtime/efimain.greg.c
@@ -176,7 +176,7 @@ __msabi noasan EFI_STATUS EfiMain(EFI_HANDLE ImageHandle,
   SystemTable->BootServices->AllocatePages(
       AllocateAddress, EfiRuntimeServicesData,
       ((_end - __executable_start) + 4095) / 4096, &Address);
-  mm = (struct mman *)0x0500;
+  mm = __get_mm_phy();
   SystemTable->BootServices->SetMem(mm, sizeof(*mm), 0);
   SystemTable->BootServices->SetMem(
       (void *)0x79000, 0x7e000 - 0x79000 + sizeof(struct EfiArgs), 0);
diff --git a/libc/runtime/pc.internal.h b/libc/runtime/pc.internal.h
index cc55cbd39..6f815fd11 100644
--- a/libc/runtime/pc.internal.h
+++ b/libc/runtime/pc.internal.h
@@ -225,5 +225,8 @@ forceinline void outb(unsigned short port, unsigned char byte) {
     (uint64_t *)(BANE + cr3);         \
   })
 
+#define __get_mm()     ((struct mman *)(BANE + 0x0500))
+#define __get_mm_phy() ((struct mman *)0x0500)
+
 #endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */
 #endif /* COSMOPOLITAN_LIBC_RUNTIME_PC_H_ */
diff --git a/libc/vga/vga-init.greg.c b/libc/vga/vga-init.greg.c
index a4d4de62d..bdfa3ae7a 100644
--- a/libc/vga/vga-init.greg.c
+++ b/libc/vga/vga-init.greg.c
@@ -35,7 +35,7 @@ struct Tty _vga_tty;
 
 void _vga_reinit(struct Tty *tty, unsigned short starty, unsigned short startx,
                  unsigned init_flags) {
-  struct mman *mm = (struct mman *)(BANE + 0x0500);
+  struct mman *mm = __get_mm();
   unsigned char vid_type = mm->pc_video_type;
   unsigned short height = mm->pc_video_height, width = mm->pc_video_width,
                  stride = mm->pc_video_stride;
@@ -66,7 +66,7 @@ void _vga_reinit(struct Tty *tty, unsigned short starty, unsigned short startx,
 
 textstartup void _vga_init(void) {
   if (IsMetal()) {
-    struct mman *mm = (struct mman *)(BANE + 0x0500);
+    struct mman *mm = __get_mm();
     unsigned short starty = mm->pc_video_curs_info.y,
                    startx = mm->pc_video_curs_info.x;
     _vga_reinit(&_vga_tty, starty, startx, 0);