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Fix metal bugs so deathstar.com runs in qemu (#20)

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- Remove XD bit in page tables
- Fix cylinder+head+sector arithmetic
- Implement fstat() for serial file descriptors on metal

Here's how to boot an Actually Portable Executable in QEMU:

    make -j12 o//tool/viz/deathstar.com
    qemu-system-x86_64 -serial stdio -fda o//tool/viz/deathstar.com

Here's a screenshot of DEATHSTAR.COM booted in QEMU:
https://justine.lol/cosmopolitan/cosmo-metal-qemu.png

Thus metal support is in much better shape now, but still incomplete.
Only a few system calls have been polyfilled. To figure out which ones
your program needs, simply boot it in the blinkenlights emulator with a
breakpoint, and press CTRL-C to continue to the system call breakpoint.
If it doesn't break then you should be good. (Note: to emulate normally
you can press 'c' and use CTRL-T and ALT-T to tune the speed.)

    m=tiny
    make -j12 SILENT=0 MODE=$m          \
      o/$m/tool/build/blinkenlights.com \
      o/$m/tool/viz/deathstar.com
    o/$m/tool/build/blinkenlights.com   \
      -r -t -b systemfive.linux         \
      o/$m/tool/viz/deathstar.com

Thank @Theldus for the bug report that made this change possible.
Fixes #20 which explains this change further.
This commit is contained in:
Justine Tunney
2021-01-16 17:52:15 -08:00
parent 58d9659d53
commit f0600a898c
13 changed files with 182 additions and 119 deletions
Download Patch File Download Diff File Expand all files Collapse all files

31
ape/ape.S
View File

@ -239,18 +239,17 @@ pc: cld
/ can have an understanding of physical locality, which deeply / can have an understanding of physical locality, which deeply
/ impacts the latency of operations. / impacts the latency of operations.
/ /
/ - 160KB: 1 head × 40 cylinders × 8 sectors × 512 = 163,840 / - 160KB: 40 cylinders × 1 head × 8 sectors × 512 = 163,840
/ - 180KB: 1 head × 40 cylinders × 9 sectors × 512 = 184,320 / - 180KB: 40 cylinders × 1 head × 9 sectors × 512 = 184,320
/ - 320KB: 2 heads × 40 cylinders × 8 sectors × 512 = 327,680 / - 320KB: 40 cylinders × 2 heads × 8 sectors × 512 = 327,680
/ - 360KB: 2 heads × 40 cylinders × 9 sectors × 512 = 368,640 / - 360KB: 40 cylinders × 2 heads × 9 sectors × 512 = 368,640
/ - 720KB: 2 heads × 80 cylinders × 9 sectors × 512 = 737,280 / - 720KB: 80 cylinders × 2 heads × 9 sectors × 512 = 737,280
/ - 1.2MB: 2 heads × 80 cylinders × 15 sectors × 512 = 1,228,800 / - 1.2MB: 80 cylinders × 2 heads × 15 sectors × 512 = 1,228,800
/ - 1.44MB: 2 heads × 80 cylinders × 18 sectors × 512 = 1,474,560 / - 1.44MB: 80 cylinders × 2 heads × 18 sectors × 512 = 1,474,560
/ /
/ Terminology / Terminology
/ /
/ - Cylinder / Tracks should mean the same thing / - Heads are also known as Tracks
/ - Heads / Sides / Spindles should mean the same thing
/ /
/ Disk Base Table / Disk Base Table
/ /
@ -341,18 +340,18 @@ pcread: push %ax
pop %cx pop %cx
pop %ax pop %ax
jc 9f jc 9f
mov %es,%si mov %es,%si # addr += 512
add $512>>4,%si add $512>>4,%si
mov %si,%es mov %si,%es
inc %al inc %al # ++sector
cmp XLM(DRIVE_LAST_SECTOR),%al cmp XLM(DRIVE_LAST_SECTOR),%al
jbe 2f jbe 2f
mov $1,%al mov $1,%al
inc %cx inc %dh # ++head
cmp XLM(DRIVE_LAST_CYLINDER),%cx cmp XLM(DRIVE_LAST_HEAD),%cx
jbe 2f jb 2f
xor %cx,%cx xor %dh,%dh
inc %dh inc %cx # ++cylinder
2: ret 2: ret
9: push %ax 9: push %ax
xor %ax,%ax # try disk reset on error xor %ax,%ax # try disk reset on error

2
ape/lib/mapimage.c
View File

@ -30,7 +30,7 @@ textreal static void __map_segment(uint64_t k, uint64_t a, uint64_t b) {
textreal void __map_image(void) { textreal void __map_image(void) {
__map_segment(PAGE_V | PAGE_U, 0, (uintptr_t)_etext - IMAGE_BASE_VIRTUAL); __map_segment(PAGE_V | PAGE_U, 0, (uintptr_t)_etext - IMAGE_BASE_VIRTUAL);
__map_segment(PAGE_V | PAGE_U | PAGE_RW | PAGE_XD, __map_segment(PAGE_V | PAGE_U | PAGE_RW,
(uintptr_t)_etext - IMAGE_BASE_VIRTUAL, (uintptr_t)_etext - IMAGE_BASE_VIRTUAL,
(uintptr_t)_end - IMAGE_BASE_VIRTUAL); (uintptr_t)_end - IMAGE_BASE_VIRTUAL);
} }

50
examples/stat.c
View File

@ -11,6 +11,7 @@
#include "libc/calls/struct/stat.h" #include "libc/calls/struct/stat.h"
#include "libc/errno.h" #include "libc/errno.h"
#include "libc/fmt/fmt.h" #include "libc/fmt/fmt.h"
#include "libc/log/check.h"
#include "libc/runtime/gc.h" #include "libc/runtime/gc.h"
#include "libc/stdio/stdio.h" #include "libc/stdio/stdio.h"
#include "libc/x/x.h" #include "libc/x/x.h"
@ -23,32 +24,29 @@
void PrintFileMetadata(const char *pathname, struct stat *st) { void PrintFileMetadata(const char *pathname, struct stat *st) {
printf("\n%s:", pathname); printf("\n%s:", pathname);
if (stat(pathname, st) != -1) { CHECK_NE(-1, stat(pathname, st));
printf( printf("\n"
"\n" "%-32s%,ld\n"
"%-32s%,ld\n" "%-32s%,ld\n"
"%-32s%,ld\n" "%-32s%#lx\n"
"%-32s%#lx\n" "%-32s%#lx\n"
"%-32s%#lx\n" "%-32s%ld\n"
"%-32s%ld\n" "%-32s%#o\n"
"%-32s%#o\n" "%-32s%d\n"
"%-32s%d\n" "%-32s%d\n"
"%-32s%d\n" "%-32s%d\n"
"%-32s%d\n" "%-32s%ld\n"
"%-32s%ld\n" "%-32s%s\n"
"%-32s%s\n" "%-32s%s\n"
"%-32s%s\n" "%-32s%s\n",
"%-32s%s\n", "bytes in file", st->st_size, "physical bytes", st->st_blocks * 512,
"bytes in file", st->st_size, "physical bytes", st->st_blocks * 512, "device id w/ file", st->st_dev, "inode", st->st_ino,
"device id w/ file", st->st_dev, "inode", st->st_ino, "hard link count", "hard link count", st->st_nlink, "mode / permissions", st->st_mode,
st->st_nlink, "mode / permissions", st->st_mode, "owner id", st->st_uid, "owner id", st->st_uid, "group id", st->st_gid,
"group id", st->st_gid, "device id (if special)", st->st_rdev, "device id (if special)", st->st_rdev, "block size", st->st_blksize,
"block size", st->st_blksize, "access time", gc(xiso8601(&st->st_atim)), "access time", gc(xiso8601(&st->st_atim)), "modified time",
"modified time", gc(xiso8601(&st->st_mtim)), "c[omplicated]time", gc(xiso8601(&st->st_mtim)), "c[omplicated]time",
gc(xiso8601(&st->st_ctim))); gc(xiso8601(&st->st_ctim)));
} else {
printf(" %s\n", strerror(errno));
}
} }
int main(int argc, char *argv[]) { int main(int argc, char *argv[]) {

38
libc/calls/fstat-metal.c Normal file
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@ -0,0 +1,38 @@
/*-*- 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/internal.h"
#include "libc/calls/struct/stat.h"
#include "libc/str/str.h"
#include "libc/sysv/consts/s.h"
#include "libc/sysv/errfuns.h"
int fstat$metal(int fd, struct stat *st) {
if (fd < 0) return einval();
if (fd < g_fds.n && g_fds.p[fd].kind == kFdSerial) {
memset(st, 0, sizeof(*st));
st->st_dev = g_fds.p[fd].handle;
st->st_rdev = g_fds.p[fd].handle;
st->st_nlink = 1;
st->st_mode = S_IFCHR | 0600;
st->st_blksize = 1;
return 0;
} else {
return ebadf();
}
}

65
libc/calls/fstat-nt.c
View File

@ -35,34 +35,47 @@ textwindows int fstat$nt(int64_t handle, struct stat *st) {
uint64_t actualsize; uint64_t actualsize;
struct NtFileCompressionInfo fci; struct NtFileCompressionInfo fci;
struct NtByHandleFileInformation wst; struct NtByHandleFileInformation wst;
if (GetFileInformationByHandle(handle, &wst)) { if ((filetype = GetFileType(handle))) {
memset(st, 0, sizeof(*st)); memset(st, 0, sizeof(*st));
filetype = GetFileType(handle); switch (filetype) {
st->st_mode = case kNtFileTypeChar:
(S_IRUSR | S_IXUSR | st->st_mode = S_IFCHR | 0600;
(!(wst.dwFileAttributes & kNtFileAttributeReadonly) ? S_IWUSR : 0) | break;
((wst.dwFileAttributes & kNtFileAttributeNormal) ? S_IFREG : 0) | case kNtFileTypePipe:
((wst.dwFileAttributes & kNtFileFlagOpenReparsePoint) ? S_IFLNK : 0) | st->st_mode = S_IFIFO | 0600;
((wst.dwFileAttributes & kNtFileAttributeDirectory) break;
? S_IFDIR case kNtFileTypeDisk:
: (((filetype == kNtFileTypeDisk) ? S_IFBLK : 0) | if (GetFileInformationByHandle(handle, &wst)) {
((filetype == kNtFileTypeChar) ? S_IFCHR : 0) | dprintf(1, "handle = %ld\n", handle);
((filetype == kNtFileTypePipe) ? S_IFIFO : 0)))); st->st_mode =
st->st_atim = FileTimeToTimeSpec(wst.ftLastAccessFileTime); (S_IRUSR | S_IXUSR |
st->st_mtim = FileTimeToTimeSpec(wst.ftLastWriteFileTime); (!(wst.dwFileAttributes & kNtFileAttributeReadonly) ? S_IWUSR
st->st_ctim = FileTimeToTimeSpec(wst.ftCreationFileTime); : 0) |
st->st_size = (uint64_t)wst.nFileSizeHigh << 32 | wst.nFileSizeLow; ((wst.dwFileAttributes & kNtFileAttributeNormal) ? S_IFREG : 0) |
st->st_blksize = PAGESIZE; ((wst.dwFileAttributes & kNtFileFlagOpenReparsePoint) ? S_IFLNK
st->st_dev = wst.dwVolumeSerialNumber; : 0) |
st->st_ino = (uint64_t)wst.nFileIndexHigh << 32 | wst.nFileIndexLow; ((wst.dwFileAttributes & kNtFileAttributeDirectory) ? S_IFDIR
st->st_nlink = wst.nNumberOfLinks; : 0));
if (GetFileInformationByHandleEx(handle, kNtFileCompressionInfo, &fci, st->st_atim = FileTimeToTimeSpec(wst.ftLastAccessFileTime);
sizeof(fci))) { st->st_mtim = FileTimeToTimeSpec(wst.ftLastWriteFileTime);
actualsize = fci.CompressedFileSize; st->st_ctim = FileTimeToTimeSpec(wst.ftCreationFileTime);
} else { st->st_size = (uint64_t)wst.nFileSizeHigh << 32 | wst.nFileSizeLow;
actualsize = st->st_size; st->st_blksize = PAGESIZE;
st->st_dev = wst.dwVolumeSerialNumber;
st->st_ino = (uint64_t)wst.nFileIndexHigh << 32 | wst.nFileIndexLow;
st->st_nlink = wst.nNumberOfLinks;
if (GetFileInformationByHandleEx(handle, kNtFileCompressionInfo, &fci,
sizeof(fci))) {
actualsize = fci.CompressedFileSize;
} else {
actualsize = st->st_size;
}
st->st_blocks = roundup(actualsize, PAGESIZE) / 512;
}
break;
default:
break;
} }
st->st_blocks = roundup(actualsize, PAGESIZE) / 512;
return 0; return 0;
} else { } else {
return __winerr(); return __winerr();

6
libc/calls/fstat.c
View File

@ -32,7 +32,11 @@ int fstat(int fd, struct stat *st) {
return weaken(__zipos_fstat)( return weaken(__zipos_fstat)(
(struct ZiposHandle *)(intptr_t)g_fds.p[fd].handle, st); (struct ZiposHandle *)(intptr_t)g_fds.p[fd].handle, st);
} else if (!IsWindows()) { } else if (!IsWindows()) {
return fstat$sysv(fd, st); if (!IsMetal()) {
return fstat$sysv(fd, st);
} else {
return fstat$metal(fd, st);
}
} else { } else {
if (!__isfdkind(fd, kFdFile)) return ebadf(); if (!__isfdkind(fd, kFdFile)) return ebadf();
return fstat$nt(g_fds.p[fd].handle, st); return fstat$nt(g_fds.p[fd].handle, st);

6
libc/calls/internal.h
View File

@ -267,6 +267,12 @@ int64_t __winerr(void) nocallback privileged;
int __mkntpath(const char *, char16_t[hasatleast PATH_MAX - 16]) hidden; int __mkntpath(const char *, char16_t[hasatleast PATH_MAX - 16]) hidden;
int __mkntpath2(const char *, char16_t[hasatleast PATH_MAX - 16], int) hidden; int __mkntpath2(const char *, char16_t[hasatleast PATH_MAX - 16], int) hidden;
/*───────────────────────────────────────────────────────────────────────────│─╗
│ cosmopolitan § syscalls » metal ─╬─│┼
╚────────────────────────────────────────────────────────────────────────────│*/
int fstat$metal(int, struct stat *);
/*───────────────────────────────────────────────────────────────────────────│─╗ /*───────────────────────────────────────────────────────────────────────────│─╗
│ cosmopolitan § syscalls » drivers ─╬─│┼ │ cosmopolitan § syscalls » drivers ─╬─│┼
╚────────────────────────────────────────────────────────────────────────────│*/ ╚────────────────────────────────────────────────────────────────────────────│*/

15
libc/calls/ischardev.c
View File

@ -30,16 +30,11 @@
textstartup bool32 ischardev(int fd) { textstartup bool32 ischardev(int fd) {
int olderr; int olderr;
struct stat st; struct stat st;
if (!IsWindows()) { olderr = errno;
olderr = errno; if (fstat(fd, &st) != -1) {
if (fstat$sysv(fd, &st) != -1) { return S_ISCHR(st.st_mode);
return S_ISCHR(st.st_mode);
} else {
errno = olderr;
return false;
}
} else { } else {
return __isfdkind(fd, kFdFile) && errno = olderr;
GetFileType(g_fds.p[fd].handle) == kNtFileTypeChar; return false;
} }
} }

4
libc/calls/madvise-nt.c
View File

@ -31,7 +31,7 @@ forceinline typeof(PrefetchVirtualMemory) *GetPrefetchVirtualMemory(void) {
if (!once) { if (!once) {
once = true; once = true;
PrefetchVirtualMemory_ = /* win8.1+ */ PrefetchVirtualMemory_ = /* win8.1+ */
GetProcAddressModule("KernelBase.dll", "PrefetchVirtualMemory"); GetProcAddressModule("Kernel32.dll", "PrefetchVirtualMemory");
} }
return PrefetchVirtualMemory_; return PrefetchVirtualMemory_;
} }
@ -42,7 +42,7 @@ forceinline typeof(OfferVirtualMemory) *GetOfferVirtualMemory(void) {
if (!once) { if (!once) {
once = true; once = true;
OfferVirtualMemory_ = /* win8.1+ */ OfferVirtualMemory_ = /* win8.1+ */
GetProcAddressModule("KernelBase.dll", "OfferVirtualMemory"); GetProcAddressModule("Kernel32.dll", "OfferVirtualMemory");
} }
return OfferVirtualMemory_; return OfferVirtualMemory_;
} }

10
libc/calls/nanosleep.c
View File

@ -27,10 +27,14 @@
int nanosleep(const struct timespec *req, struct timespec *rem) { int nanosleep(const struct timespec *req, struct timespec *rem) {
if (!req) return efault(); if (!req) return efault();
if (!IsWindows()) { if (!IsWindows()) {
if (!IsXnu()) { if (!IsMetal()) {
return nanosleep$sysv(req, rem); if (!IsXnu()) {
return nanosleep$sysv(req, rem);
} else {
return nanosleep$xnu(req, rem);
}
} else { } else {
return nanosleep$xnu(req, rem); return enosys(); /* TODO: Sleep on Metal */
} }
} else { } else {
return nanosleep$nt(req, rem); return nanosleep$nt(req, rem);

46
libc/calls/sigaction.c
View File

@ -141,32 +141,36 @@ int(sigaction)(int sig, const struct sigaction *act, struct sigaction *oldact) {
return efault(); return efault();
} }
if (!IsWindows()) { if (!IsWindows()) {
if (act) { if (!IsMetal()) {
memcpy(&copy, act, sizeof(copy)); if (act) {
ap = &copy; memcpy(&copy, act, sizeof(copy));
if (IsXnu()) { ap = &copy;
ap->sa_restorer = (void *)&xnutrampoline; if (IsXnu()) {
ap->sa_handler = (void *)&xnutrampoline; ap->sa_restorer = (void *)&xnutrampoline;
} else { ap->sa_handler = (void *)&xnutrampoline;
if (IsLinux()) { } else {
if (!(ap->sa_flags & SA_RESTORER)) { if (IsLinux()) {
ap->sa_flags |= SA_RESTORER; if (!(ap->sa_flags & SA_RESTORER)) {
ap->sa_restorer = &__restore_rt; ap->sa_flags |= SA_RESTORER;
ap->sa_restorer = &__restore_rt;
}
}
if (rva >= kSigactionMinRva) {
ap->sa_sigaction = (sigaction_f)__sigenter;
} }
} }
if (rva >= kSigactionMinRva) { sigaction$cosmo2native((union metasigaction *)ap);
ap->sa_sigaction = (sigaction_f)__sigenter; } else {
} ap = NULL;
} }
sigaction$cosmo2native((union metasigaction *)ap); rc = sigaction$sysv(
sig, ap, oldact,
(!IsXnu() ? 8 /* or linux whines */
: (int64_t)(intptr_t)oldact /* from go code */));
if (rc != -1) sigaction$native2cosmo((union metasigaction *)oldact);
} else { } else {
ap = NULL; return enosys(); /* TODO: Signals on Metal */
} }
rc = sigaction$sysv(
sig, ap, oldact,
(!IsXnu() ? 8 /* or linux whines */
: (int64_t)(intptr_t)oldact /* from go code */));
if (rc != -1) sigaction$native2cosmo((union metasigaction *)oldact);
} else { } else {
if (oldact) { if (oldact) {
memset(oldact, 0, sizeof(*oldact)); memset(oldact, 0, sizeof(*oldact));

7
libc/runtime/program_invocation_short_name.S
View File

@ -28,7 +28,10 @@ program_invocation_short_name:
.init.start 400,_init_program_invocation_short_name .init.start 400,_init_program_invocation_short_name
push %rsi push %rsi
mov (%r13),%rsi xor %eax,%eax
test %r12d,%r12d # argc
jz 2f
mov (%r13),%rsi # argv[0]
mov %rsi,%rcx mov %rsi,%rcx
1: lodsb 1: lodsb
cmp $'/,%al cmp $'/,%al
@ -39,5 +42,5 @@ program_invocation_short_name:
jnz 1b jnz 1b
xchg %rcx,%rax xchg %rcx,%rax
pop %rsi pop %rsi
stosq 2: stosq
.init.end 400,_init_program_invocation_short_name .init.end 400,_init_program_invocation_short_name

21
tool/build/blinkenlights.c
View File

@ -1789,14 +1789,14 @@ static void OnDiskServiceBadCommand(void) {
} }
static void OnDiskServiceGetParams(void) { static void OnDiskServiceGetParams(void) {
size_t lastsector, lasttrack, lasthead; size_t lastsector, lastcylinder, lasthead;
lasthead = GetLastIndex(elf->mapsize, 512 * 63 * 1024, 0, 255); lastcylinder = GetLastIndex(elf->mapsize, 512 * 63 * 255, 0, 1023);
lasttrack = GetLastIndex(elf->mapsize, 512 * 63, 0, 1023); lasthead = GetLastIndex(elf->mapsize, 512 * 63, 0, 255);
lastsector = GetLastIndex(elf->mapsize, 512, 1, 63); lastsector = GetLastIndex(elf->mapsize, 512, 1, 63);
m->dx[0] = 1; m->dx[0] = 1;
m->dx[1] = lasthead; m->dx[1] = lasthead;
m->cx[0] = lasttrack >> 8 << 6 | lastsector; m->cx[0] = lastcylinder >> 8 << 6 | lastsector;
m->cx[1] = lasttrack; m->cx[1] = lastcylinder;
m->ax[1] = 0; m->ax[1] = 0;
Write64(m->es, 0); Write64(m->es, 0);
Write16(m->di, 0); Write16(m->di, 0);
@ -1806,18 +1806,17 @@ static void OnDiskServiceGetParams(void) {
static void OnDiskServiceReadSectors(void) { static void OnDiskServiceReadSectors(void) {
static int x; static int x;
uint64_t addr, size; uint64_t addr, size;
int64_t sectors, drive, head, track, sector, offset; int64_t sectors, drive, head, cylinder, sector, offset;
sectors = m->ax[0]; sectors = m->ax[0];
drive = m->dx[0]; drive = m->dx[0];
head = m->dx[1]; head = m->dx[1];
track = (m->cx[0] & 0b11000000) << 2 | m->cx[1]; cylinder = (m->cx[0] & 0b11000000) << 2 | m->cx[1];
sector = (m->cx[0] & 0b00111111) - 1; sector = (m->cx[0] & 0b00111111) - 1;
offset = head * track * sector * 512;
size = sectors * 512; size = sectors * 512;
offset = sector * 512 + track * 512 * 63 + head * 512 * 63 * 1024; offset = sector * 512 + head * 512 * 63 + cylinder * 512 * 63 * 255;
VERBOSEF("bios read sectors %d " VERBOSEF("bios read sectors %d "
"@ sector %ld track %ld head %ld drive %ld offset %#lx", "@ sector %ld cylinder %ld head %ld drive %ld offset %#lx",
sectors, sector, track, head, drive, offset); sectors, sector, cylinder, head, drive, offset);
if (0 <= sector && offset + size <= elf->mapsize) { if (0 <= sector && offset + size <= elf->mapsize) {
addr = Read64(m->es) + Read16(m->bx); addr = Read64(m->es) + Read16(m->bx);
if (addr + size <= m->real.n) { if (addr + size <= m->real.n) {