cosmopolitan/libc/intrin/directmap-metal.c
Justine Tunney e522aa3a07
Make more threading improvements
- ASAN memory morgue is now lockless
- Make C11 atomics header more portable
- Rewrote pthread keys support to be lockless
- Simplify Python's unicode table unpacking code
- Make crash report write(2) closer to being atomic
- Make it possible to strace/ftrace a single thread
- ASAN now checks nul-terminated strings fast and properly
- Windows fork() now restores TLS memory of calling thread
2022-11-01 23:28:26 -07:00

72 lines
3.4 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
╞══════════════════════════════════════════════════════════════════════════════╡
│ Copyright 2021 Justine Alexandra Roberts Tunney │
│ │
│ Permission to use, copy, modify, and/or distribute this software for │
│ any purpose with or without fee is hereby granted, provided that the │
│ above copyright notice and this permission notice appear in all copies. │
│ │
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
│ PERFORMANCE OF THIS SOFTWARE. │
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/calls/calls.h"
#include "libc/intrin/directmap.internal.h"
#include "libc/macros.internal.h"
#include "libc/runtime/pc.internal.h"
#include "libc/str/str.h"
#include "libc/sysv/consts/map.h"
#include "libc/sysv/consts/prot.h"
#include "libc/sysv/errfuns.h"
static uint64_t sys_mmap_metal_break;
noasan struct DirectMap sys_mmap_metal(void *paddr, size_t size, int prot,
int flags, int fd, int64_t off) {
/* asan runtime depends on this function */
size_t i;
struct mman *mm;
struct DirectMap res;
uint64_t addr, page, *pte, *pml4t;
mm = (struct mman *)(BANE + 0x0500);
pml4t = __get_pml4t();
size = ROUNDUP(size, 4096);
addr = (uint64_t)paddr;
if (!(flags & MAP_FIXED)) {
if (!addr) addr = 4096;
for (i = 0; i < size; i += 4096) {
pte = __get_virtual(mm, pml4t, addr + i, false);
if (pte && (*pte & (PAGE_V | PAGE_RSRV))) {
addr = MAX(addr, sys_mmap_metal_break) + i + 4096;
i = 0;
}
}
sys_mmap_metal_break = MAX(addr + size, sys_mmap_metal_break);
}
for (i = 0; i < size; i += 4096) {
page = __new_page(mm);
pte = __get_virtual(mm, pml4t, addr + i, true);
if (pte && page) {
__clear_page(BANE + page);
page |= PAGE_RSRV | PAGE_U;
if ((prot & PROT_WRITE))
page |= PAGE_V | PAGE_RW;
else if ((prot & (PROT_READ | PROT_EXEC)))
page |= PAGE_V;
if (!(prot & PROT_EXEC)) page |= PAGE_XD;
*pte = page;
} else {
addr = -1;
break;
}
}
res.addr = (void *)addr;
res.maphandle = -1;
return res;
}