mirror of
https://github.com/jart/cosmopolitan.git
synced 2025-01-31 11:37:35 +00:00
6ffed14b9c
Actually Portable Executable now supports Android. Cosmo's old mmap code required a 47 bit address space. The new implementation is very agnostic and supports both smaller address spaces (e.g. embedded) and even modern 56-bit PML5T paging for x86 which finally came true on Zen4 Threadripper Cosmopolitan no longer requires UNIX systems to observe the Windows 64kb granularity; i.e. sysconf(_SC_PAGE_SIZE) will now report the host native page size. This fixes a longstanding POSIX conformance issue, concerning file mappings that overlap the end of file. Other aspects of conformance have been improved too, such as the subtleties of address assignment and and the various subtleties surrounding MAP_FIXED and MAP_FIXED_NOREPLACE On Windows, mappings larger than 100 megabytes won't be broken down into thousands of independent 64kb mappings. Support for MAP_STACK is removed by this change; please use NewCosmoStack() instead. Stack overflow avoidance is now being implemented using the POSIX thread APIs. Please use GetStackBottom() and GetStackAddr(), instead of the old error-prone GetStackAddr() and HaveStackMemory() APIs which are removed.
426 lines
17 KiB
ArmAsm
426 lines
17 KiB
ArmAsm
/*-*- mode:unix-assembly; indent-tabs-mode:t; tab-width:8; coding:utf-8 -*-│
|
||
│ vi: set noet ft=asm ts=8 sw=8 fenc=utf-8 :vi │
|
||
╞══════════════════════════════════════════════════════════════════════════════╡
|
||
│ Copyright 2020 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/dce.h"
|
||
#include "libc/macros.internal.h"
|
||
#include "libc/thread/pt.internal.h"
|
||
|
||
#define SIG_IGN 1
|
||
|
||
/* ▄▄▄
|
||
▄▄▄ ▀▓▓▒▄
|
||
▄▓▒▒░ ▀▓▒▒▒▄
|
||
▄▓▓▓▒▀ ▄▄▄▄ ▒▓▒▒░▒▄
|
||
▄▓▓▓▒▓ ▄▄▓██▓▓▓▓▒▒▒▒▓▓▄▄▓▓▒▒▒░░▒
|
||
▓▓▓▓▒▒▒▄▄ ░▒█▓▓▓▓▓▓▓▓▓▒▒▒▒▒▒▒▒▒▒▒▓▒░░▒░
|
||
██▓▓▓▒▒░░▒▒▒▒▓▓▓▓▓▓▒▓▒░▒▒░▀▒▒▒▒░▀░▒▒▒░▒
|
||
▓▓▓▓▓▓▓▒▒▒▒▒▒▓▓▒▓▓▒▒▒░▒▒░░ ░▒▒░ ░▒▒▒▒
|
||
▀▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▒▒░░▒░░ ░▒▒ ░ ▀▒▒
|
||
▀▓▓█▓▓▓▓▓▓▓▓▓▓▒▒░░▒▒░░ ░░░▓░ ▓░░░▒
|
||
▀▀█▓███▓▓▓▓▓▒▒░░░▒░░ ░█▓░█▓░█▓▓▄▒░
|
||
░▓██▓▓▓▓▓▒▒░░░▒░░ ░████▓▒▓█▓▀░▀▄
|
||
░▓██▓▓▓▓▓▒▒▒░░░▒░░ ▒██▓▒▒▒▒▒▒░░░▒
|
||
████▓▓▓▓▓▒▒▒▒▒▒▒▒▒░░▒▓▓▒░░░░▒░░░▒░ ░░░░░
|
||
░▓███▓▓▓▓▓▒▒░░░░░░░▒▒▒▒▒▒▒▒▒▒▒░░░ ░░░░░ ░
|
||
▓███▓▓▓▓▓▒▓▒▒▒▒░░░░░░░░░▒▓▒▒░▀ ░░░ ░░░░░
|
||
▀▒██▓▓▓▓▒▒▒▓▓▓▓▒▒▒▒▒▒▒▓▀▀░ ░░░░░░░░░ ░
|
||
▓▓▓▓▓▓▓▒▓▒▒▒▒▓▓▓▒▀░ ░░░░░▄░░░ ░░░ ░░░░░░
|
||
▓▓▓▒▒▒▒▒▒▒▒▒▒▒▓ █▓▒░░▒░░░░ ░░░░░░░░
|
||
▄▓▓▓▒▒▒▒▒░░░░░░░▒▄▄▄░▒▓▓▒▒░▀░
|
||
░▓█▓▓▒▒▒▒▒▒▒▒▒▒▒▒▒▒▓▓▓▓▓▓▒░░░▒ besiyata
|
||
▓▓█▓▓▒▓▓▓▒▒▒░░░░░░▒▓▓▓▓▒▒▒▒▒░ dishmaya
|
||
▓▓█▓▓▓▓▓▓▒▒▒░░░░░░░▒▓▓▒▀▀▀
|
||
▓▓██▓▓▓▓▓▓▓▒▒▒▒▒▒▒▒▒▒▀
|
||
█▓▓█▓▓▓▓▓▓▓▓▓▓▓▓▓▓▓▀
|
||
▒▓▓▓▓▀░░▒▓▓▓▓▓▓▓▓▒▒░░▒
|
||
▄▓▓▀░░░▄▓▓▓▓▒▒▒▒▒░░░░▄░
|
||
▄███▄▄▓▓▓▓▓▓▓▒▒▒▒▒░░▒▒░
|
||
▄▓▓▓█▓█▓▓███▓▓▓▓▓▓▓▓▓▓▓░
|
||
▄░▓▓▓▓▓▓▀▒▓▓▓▒▒▓▒░░░▒▓▒░░░▓
|
||
▄▄▄░▒▓▓▓▓▓▓░▀▀ ▓▓▒░▓▒▒▒▒▒▒▒▒▒▒▄░░▀▀░░ ▄▄▄▄
|
||
▄▄▄▒▒▓▓█▓▓▓▓▓▀▀▀▀▀ ▓▓▓▓▓▒▒▒▒▒▒▒▒▒▒▒▒▒▀░░▀░░▒▒▒░░░ ░░░░░
|
||
▄▓▓▓▒▀▀ ▓▒▓▓▓▓▓▒▒▒▒▒▒▒▒▓░░░ ▒▒▒░░░░░░░░▒
|
||
█▓▓▒ ▄▄▄ ▀▓▒▓▒▒▒▓▓▓▓▓▓▒▒▒░░░░░░░░░▒▒░░░░░░░
|
||
▀▓▓▓▓▒▄▄▒▒▒▒▒▒▄▄ ▀▀▀▀░░▒▒▒▒░░░░░░
|
||
▀▀▀▓▓▓▓▒▒▒▒▒▓▓▄▄
|
||
╔────────────────────────────────────────────────────────────────────────────│─╗
|
||
│ cosmopolitan § bell system five » system call support ─╬─│┼
|
||
╚────────────────────────────────────────────────────────────────────────────│*/
|
||
|
||
.initbss 300,_init_systemfive
|
||
|
||
// Performs System Five System Call.
|
||
//
|
||
// Cosmopolitan is designed to delegate all function calls into the
|
||
// Linux, FreeBSD, OpenBSD, and XNU kernels via this function, with
|
||
// few exceptions. This function should generally only be called by
|
||
// generated thunks in the libc/sysv/syscalls/ directory.
|
||
//
|
||
// It's safe to call this function on Windows, where it will always
|
||
// return -1 with errno == ENOSYS. Further note that -1 is the only
|
||
// return value that means error, a common anti-pattern is to check
|
||
// for values less than 0 (which is more problematic on 32-bit).
|
||
//
|
||
// It is important to consider that system calls are one order of a
|
||
// magnitude more expensive than normal function calls. For example
|
||
// getpid() on Linux usually takes 500ns, and cached i/o calls will
|
||
// take 1µs or more. So we don't need to inline them like Chromium.
|
||
//
|
||
// Another thing to consider is that BSDs only loosely follow the
|
||
// System Five ABI for the SYSCALL instruction. For example Linux
|
||
// always follows the six argument limit but the FreeBSD sendfile
|
||
// system call accepts a seventh argument that is passed on stack
|
||
// and OpenBSD modifies functions like mmap so that the sixth arg
|
||
// is passed on the stack. There's also the carry flag convention
|
||
// that XNU, FreeBSD, and OpenBSD inherited from 386BSD aka Jolix
|
||
//
|
||
// @param %rax function ordinal supplied by jump slot
|
||
// @param %rdi,%rsi,%rdx,%rcx,%r8,%r9 and rest on stack
|
||
// @return %rax:%rdx is result, or -1 w/ errno on error
|
||
// @clob %rcx,%r10,%r11
|
||
// @see syscalls.sh
|
||
__systemfive:
|
||
.quad 0
|
||
.endobj __systemfive,globl,hidden
|
||
__pid: .quad 0
|
||
.endobj __pid,globl,hidden
|
||
.previous
|
||
|
||
systemfive_cp:
|
||
push %rbp
|
||
mov %rsp,%rbp // so backtraces work
|
||
systemfive_cancellable: // our pthread_cancel() miracle code
|
||
cmpb $0,__tls_enabled(%rip) // inspired by the musl libc design!
|
||
je 1f // we handle linux and bsd together!
|
||
mov %gs:0x30,%r10 // CosmoTib::tib_self
|
||
mov 0x28(%r10),%r10 // CosmoTib::tib_pthread
|
||
test %r10,%r10 // is it a posix thread?
|
||
jz 1f // it's spawn() probably
|
||
testb $PT_NOCANCEL,0x00(%r10) // PosixThread::flags
|
||
jnz 1f // canceler no cancelling
|
||
#if IsModeDbg()
|
||
testb $PT_INCANCEL,0x00(%r10)
|
||
jz 5f
|
||
#endif
|
||
cmpl $0,0x04(%r10) // PosixThread::cancelled
|
||
jne systemfive_cancel // we will tail call below
|
||
1: mov %rcx,%r10 // move the fourth argument
|
||
clc // no cancellable system calls exist
|
||
syscall // that have 7+ args on the bsd OSes
|
||
systemfive_cancellable_end: // i/o calls park here for long time
|
||
pop %rbp
|
||
jnc 2f
|
||
neg %rax // turns bsd errno to system v errno
|
||
2: cmp $-4095,%rax // but we still check again on eintr
|
||
jae 3f // branch because system call failed
|
||
ret // done if the system call succeeded
|
||
3: neg %eax // now examine the nature of failure
|
||
cmp EINTR(%rip),%eax // did the SIGTHR cancel our IO call
|
||
jne systemfive_errno // werent interrupted by OnSigCancel
|
||
cmpb $0,__tls_enabled(%rip) // make sure it's safe to grab %fs:0
|
||
je systemfive_errno // tls is disabled we can't continue
|
||
mov %gs:0x30,%rcx // CosmoTib::tib_self
|
||
mov 0x28(%rcx),%rcx // CosmoTib::tib_pthread
|
||
test %rcx,%rcx // is it a posix thread?
|
||
jz systemfive_errno // it's spawn() probably
|
||
testb $PT_NOCANCEL,0x00(%rcx) // PosixThread::flags
|
||
jnz systemfive_errno // cancellation is disabled
|
||
cmpl $0,0x04(%rcx) // PosixThread::cancelled
|
||
je systemfive_errno // we aren't actually cancelled
|
||
jmp 4f // now we are in fact cancelled
|
||
systemfive_cancel: // SIGTHR will jump here too
|
||
pop %rbp
|
||
4: jmp _pthread_cancel_ack // tail call
|
||
.weak _pthread_cancel_ack // must be linked if we're cancelled
|
||
#if IsModeDbg()
|
||
not_a_cancellation_point: // need BEGIN/END_CANCELLATION_POINT
|
||
nop
|
||
.weak report_cancellation_point
|
||
5: ezlea report_cancellation_point,cx
|
||
test %rcx,%rcx
|
||
jz 6f
|
||
call *%rcx
|
||
6: ud2
|
||
nop
|
||
#endif
|
||
.globl systemfive_cancellable_end
|
||
.globl systemfive_cancellable
|
||
.globl systemfive_cancel
|
||
.endfn systemfive_cp
|
||
|
||
.Lanchorpoint:
|
||
#if SupportsLinux() || SupportsMetal()
|
||
systemfive_linux:
|
||
and $0xfff,%eax // remove nonlinux bits from ordinal
|
||
cmp $0xfff,%eax // checks if unsupported by platform
|
||
je systemfive_enosys // never taken branches cost nothing
|
||
btr $11,%eax // 0x800 means a call is cancellable
|
||
jc systemfive_cp // it is handled by the holiest code
|
||
mov %rcx,%r10 // syscall instruction clobbers %rcx
|
||
push %rbp // linux never reads args from stack
|
||
mov %rsp,%rbp // having frame will help backtraces
|
||
syscall // this is known as a context switch
|
||
pop %rbp // next we check to see if it failed
|
||
cmp $-4095,%rax // system five nexgen32e abi § a.2.1
|
||
jae systemfive_error // encodes errno as neg return value
|
||
ret
|
||
.endfn systemfive_linux,globl,hidden
|
||
systemfive_error:
|
||
neg %eax
|
||
// 𝑠𝑙𝑖𝑑𝑒
|
||
.endfn systemfive_error,globl,hidden
|
||
#endif
|
||
systemfive_errno:
|
||
xchg %eax,%ecx
|
||
.errno
|
||
mov %ecx,(%rax) // normalize to c library convention
|
||
push $-1 // negative one is only error result
|
||
pop %rax // the push pop is to save code size
|
||
ret
|
||
.endfn systemfive_errno,globl,hidden
|
||
systemfive_enosys:
|
||
mov ENOSYS(%rip),%eax
|
||
jmp systemfive_errno
|
||
.endfn systemfive_enosys,globl,hidden
|
||
#if SupportsNetbsd()
|
||
systemfive_netbsd:
|
||
shr $4*13,%rax
|
||
jmp systemfive_bsdscrub
|
||
.endfn systemfive_netbsd,globl,hidden
|
||
#endif
|
||
#if SupportsOpenbsd()
|
||
systemfive_openbsd:
|
||
shr $4*10,%rax
|
||
jmp systemfive_bsdscrub
|
||
.endfn systemfive_openbsd,globl,hidden
|
||
#endif
|
||
#if SupportsFreebsd()
|
||
systemfive_freebsd:
|
||
shr $4*7,%rax
|
||
movzwl %ax,%eax
|
||
// 𝑠𝑙𝑖𝑑𝑒
|
||
.endfn systemfive_freebsd,globl,hidden
|
||
#endif
|
||
#if SupportsBsd()
|
||
systemfive_bsdscrub:
|
||
and $0xfff,%eax
|
||
// 𝑠𝑙𝑖𝑑𝑒
|
||
.endfn systemfive_bsdscrub,globl,hidden
|
||
systemfive_bsd:
|
||
cmp $0xfff,%ax
|
||
je systemfive_enosys
|
||
btr $11,%eax // checks/reset the 800 cancellable bit
|
||
jc systemfive_cp
|
||
mov %rcx,%r10
|
||
syscall // bsd will need arg on stack sometimes
|
||
jc systemfive_errno // bsd sets carry flag if %rax is errno
|
||
ret
|
||
.endfn systemfive_bsd
|
||
#endif
|
||
#if SupportsXnu()
|
||
systemfive_xnu:
|
||
// 0x?????????2153??? // how syscalls.sh encodes xnu ordinals
|
||
// │└┴┴┐
|
||
// │ ├┬┐
|
||
// 0x0000000002000153 // how xnu wants ordinals to be encoded
|
||
mov %eax,%r11d
|
||
and $0x0f000000,%r11d
|
||
shl $8,%eax
|
||
shr $20,%eax
|
||
or %r11d,%eax
|
||
jmp systemfive_bsd
|
||
.endfn systemfive_xnu,globl,hidden
|
||
#endif
|
||
.previous
|
||
|
||
// Initializes System Five system call support.
|
||
//
|
||
// (1) Extracts parameters passed by kernel
|
||
// (2) Detects OS without issuing system calls
|
||
// (3) Unpacks magnums from libc/sysv/consts.sh
|
||
// (4) Replaces stack with one we control
|
||
//
|
||
// @param %r15 is auxv
|
||
// @note OpenBSD devs: let us know if you start using auxv
|
||
.init.start 300,_init_systemfive
|
||
push %rbx
|
||
push %rsi
|
||
// Detect the operating system.
|
||
mov __hostos(%rip),%eax
|
||
#if SupportsWindows() || SupportsXnu() || SupportsFreebsd()
|
||
// set by libc/ape.S for XNU
|
||
// set by libc/crt/crt.S for XNU/FreeBSD
|
||
// set by libc/nt/winmain.greg.c for New Technology
|
||
test %eax,%eax
|
||
jnz _init_systemfive_detected // os is already known
|
||
#endif
|
||
#if SupportsOpenbsd()
|
||
cmpq $0,(%r15) // OpenBSD has no auxv
|
||
jnz 0f
|
||
mov $_HOSTOPENBSD,%al
|
||
jmp _init_systemfive_detected
|
||
0:
|
||
#endif
|
||
#if SupportsNetbsd()
|
||
xor %ecx,%ecx
|
||
0: cmpq $2014,(%r15,%rcx,8) // NetBSD's AT_EXECFN
|
||
jne 1f
|
||
mov $_HOSTNETBSD,%al
|
||
jmp _init_systemfive_detected
|
||
1: cmpq $0,(%r15,%rcx,8)
|
||
lea 2(%ecx),%ecx
|
||
jnz 0b
|
||
2:
|
||
#endif
|
||
mov $_HOSTLINUX,%al
|
||
_init_systemfive_detected:
|
||
mov %eax,__hostos(%rip)
|
||
bsr %eax,%eax
|
||
mov $_init_systemfive_jmptab,%ebx
|
||
movzbl (%rbx,%rax),%eax
|
||
lea (%rbx,%rax),%eax
|
||
jmp *%rax
|
||
_init_systemfive_jmptab:
|
||
.byte _init_systemfive_linux-_init_systemfive_jmptab
|
||
.byte _init_systemfive_metal-_init_systemfive_jmptab
|
||
.byte _init_systemfive_windows-_init_systemfive_jmptab
|
||
.byte _init_systemfive_xnu-_init_systemfive_jmptab
|
||
.byte _init_systemfive_openbsd-_init_systemfive_jmptab
|
||
.byte _init_systemfive_freebsd-_init_systemfive_jmptab
|
||
.byte _init_systemfive_netbsd-_init_systemfive_jmptab
|
||
.endobj _init_systemfive_jmptab
|
||
_init_systemfive_linux:
|
||
#if SupportsLinux()
|
||
pushb systemfive_linux-.Lanchorpoint
|
||
mov $syscon_linux,%esi
|
||
jmp _init_systemfive_os
|
||
#endif
|
||
.endfn _init_systemfive_linux
|
||
_init_systemfive_metal:
|
||
#if SupportsMetal()
|
||
pushb systemfive_enosys-.Lanchorpoint
|
||
mov $syscon_linux,%esi
|
||
jmp _init_systemfive_os
|
||
#endif
|
||
.endfn _init_systemfive_metal
|
||
_init_systemfive_windows:
|
||
#if SupportsWindows()
|
||
pushb systemfive_enosys-.Lanchorpoint
|
||
mov $syscon_windows,%esi
|
||
jmp _init_systemfive_os
|
||
#endif
|
||
.endfn _init_systemfive_windows
|
||
_init_systemfive_xnu:
|
||
#if SupportsXnu()
|
||
pushb systemfive_xnu-.Lanchorpoint
|
||
mov $syscon_xnu,%esi
|
||
jmp _init_systemfive_os
|
||
#endif
|
||
.endfn _init_systemfive_xnu
|
||
_init_systemfive_openbsd:
|
||
#if SupportsOpenbsd()
|
||
pushb systemfive_openbsd-.Lanchorpoint
|
||
mov $syscon_openbsd,%esi
|
||
jmp _init_systemfive_os
|
||
#endif
|
||
.endfn _init_systemfive_openbsd
|
||
_init_systemfive_freebsd:
|
||
#if SupportsFreebsd()
|
||
pushb systemfive_freebsd-.Lanchorpoint
|
||
mov $syscon_freebsd,%esi
|
||
jmp _init_systemfive_os
|
||
#endif
|
||
.endfn _init_systemfive_freebsd
|
||
_init_systemfive_netbsd:
|
||
#if SupportsNetbsd()
|
||
pushb systemfive_netbsd-.Lanchorpoint
|
||
mov $syscon_netbsd,%esi
|
||
// 𝑠𝑙𝑖𝑑𝑒
|
||
#endif
|
||
.endfn _init_systemfive_netbsd
|
||
_init_systemfive_os:
|
||
pop %rax
|
||
add $.Lanchorpoint,%eax
|
||
stosq #→ __systemfive
|
||
// 𝑠𝑙𝑖𝑑𝑒
|
||
.endfn _init_systemfive_os
|
||
_init_systemfive_magnums:
|
||
push %rdi
|
||
mov $syscon_start,%edi
|
||
2: cmp $syscon_end,%edi
|
||
jnb 5f
|
||
xor %ebx,%ebx
|
||
xor %ecx,%ecx
|
||
xor %edx,%edx
|
||
3: lodsb // decodes uleb128
|
||
movzbl %al,%edx
|
||
and $127,%dl
|
||
shl %cl,%rdx
|
||
or %rdx,%rbx
|
||
add $7,%cl
|
||
test $128,%al
|
||
jnz 3b
|
||
xchg %rbx,%rax
|
||
stosq
|
||
jmp 2b
|
||
5: nop
|
||
pop %rdi
|
||
pop %rsi
|
||
pop %rbx
|
||
// 𝑠𝑙𝑖𝑑𝑒
|
||
.endfn _init_systemfive_magnums
|
||
#if SupportsSystemv()
|
||
_init_systemfive_pid:
|
||
ezlea __hostos,cx
|
||
mov (%rcx),%al
|
||
mov (%rdi),%eax
|
||
testb $_HOSTWINDOWS|_HOSTMETAL,(%rcx)
|
||
jnz 1f
|
||
mov __NR_getpid(%rip),%eax
|
||
syscall
|
||
1: stosq
|
||
.endfn _init_systemfive_pid
|
||
#endif
|
||
#if SupportsBsd() && !defined(TINY)
|
||
_init_systemfive_sigsys:
|
||
testb IsBsd() // BSDs will trap SIGSYS!
|
||
jz 1f // We want ENOSYS instead
|
||
push %rdi // XNU removed some calls
|
||
push %rsi // in past, so this makes
|
||
xor %eax,%eax // troubleshooting easier
|
||
push %rax // but it's non-essential
|
||
push %rax
|
||
push %rax
|
||
push %rax
|
||
push %rax
|
||
push $SIG_IGN // sigaction_meta size 48
|
||
mov __NR_sigaction(%rip),%eax // mag
|
||
mov SIGSYS(%rip),%edi // sig
|
||
mov %rsp,%rsi // new
|
||
xor %edx,%edx // old
|
||
mov $8,%r10d // for linux
|
||
xor %r8d,%r8d // for netbsd
|
||
syscall
|
||
add $6*8,%rsp
|
||
pop %rsi
|
||
pop %rdi
|
||
1: .endfn _init_systemfive_sigsys
|
||
#endif
|
||
_init_systemfive_done:
|
||
nop
|
||
.init.end 300,_init_systemfive,globl,hidden
|