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[metal] Allow (re)mapping "/ape.com" into virtual memory

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This commit is contained in:
tkchia 2022-10-18 22:59:04 +00:00
parent ad8339426e
commit 3b20faf371
3 changed files with 56 additions and 16 deletions
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4
ape/ape.lds
View file

@ -565,10 +565,10 @@ SHSTUB2(ape_loader_dd_count,
#if SupportsMetal()
HIDDEN(v_ape_realsectors =
MIN(0x70000 - IMAGE_BASE_REAL,
ROUNDUP(RVA(_edata), 512)) / 512);
ROUNDUP(RVA(_tdata_end), 512)) / 512);
HIDDEN(v_ape_realpages = v_ape_realsectors / (4096 / 512));
HIDDEN(v_ape_highsectors =
(ROUNDUP(RVA(_edata), 512) / 512) - v_ape_realsectors);
(ROUNDUP(RVA(_tdata_end), 512) / 512) - v_ape_realsectors);
TSSDESCSTUB2(_tss, _tss, _tss_end ? _tss_end - _tss - 1 : 0);
#endif

1
libc/calls/getprogramexecutablename.greg.c
View file

@ -79,6 +79,7 @@ static inline void GetProgramExecutableNameImpl(char *p, char *e) {
// if argv[0] exists then turn it into an absolute path. we also try
// adding a .com suffix since the ape auto-appends it when resolving
if (__argc && (((q = __argv[0]) && !sys_faccessat(AT_FDCWD, q, F_OK, 0)) ||
IsMetal() ||
((q = StrCat(u.path, __argv[0], ".com")) &&
!sys_faccessat(AT_FDCWD, q, F_OK, 0)))) {
if (*q != '/') {

67
libc/intrin/directmap-metal.c
View file

@ -18,28 +18,56 @@
╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/calls/calls.h"
#include "libc/intrin/directmap.internal.h"
#include "libc/calls/internal.h"
#include "libc/calls/metalfile.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"
#define MAP_ANONYMOUS_linux 0x00000020
#define MAP_FIXED_linux 0x00000010
static uint64_t sys_mmap_metal_break;
noasan struct DirectMap sys_mmap_metal(void *paddr, size_t size, int prot,
noasan static struct DirectMap bad_mmap(void) {
struct DirectMap res;
res.addr = (void *)-1;
res.maphandle = -1;
return res;
}
noasan struct DirectMap sys_mmap_metal(void *vaddr, 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;
uint64_t addr, faddr = 0, page, *pte, *fdpte, *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;
addr = (uint64_t)vaddr;
if (!(flags & MAP_ANONYMOUS_linux)) {
struct Fd *sfd;
struct MetalFile *file;
if (off < 0 || fd < 0 || fd >= g_fds.n) return bad_mmap();
sfd = &g_fds.p[fd];
if (sfd->kind != kFdFile) return bad_mmap();
file = (struct MetalFile *)sfd->handle;
/* TODO: allow mapping partial page at end of file, if file size not
* multiple of page size */
if (off > file->size || size > file->size - off) return bad_mmap();
faddr = (uint64_t)file->base + off;
if (faddr % 4096 != 0) return bad_mmap();
}
if (!(flags & MAP_FIXED_linux)) {
if (!addr) {
addr = 4096;
} else {
addr = ROUNDUP(addr, 4096);
}
for (i = 0; i < size; i += 4096) {
pte = __get_virtual(mm, pml4t, addr + i, false);
if (pte && (*pte & (PAGE_V | PAGE_RSRV))) {
@ -52,15 +80,26 @@ noasan struct DirectMap sys_mmap_metal(void *paddr, size_t size, int prot,
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;
if (pte) {
if ((flags & MAP_ANONYMOUS_linux)) {
page = __new_page(mm);
if (!page) return bad_mmap();
__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;
} else {
fdpte = __get_virtual(mm, pml4t, faddr + i, false);
page = *fdpte;
page |= PAGE_RSRV | PAGE_U;
if (!(prot & PROT_WRITE)) page &= ~PAGE_RW;
if (!(prot & PROT_EXEC)) page |= PAGE_XD;
}
*pte = page;
invlpg(addr + i);
} else {
addr = -1;
break;