diff options
Diffstat (limited to 'src/runtime/sys_linux_386.s')
-rw-r--r-- | src/runtime/sys_linux_386.s | 489 |
1 files changed, 489 insertions, 0 deletions
diff --git a/src/runtime/sys_linux_386.s b/src/runtime/sys_linux_386.s new file mode 100644 index 000000000..0f6d4bbb5 --- /dev/null +++ b/src/runtime/sys_linux_386.s @@ -0,0 +1,489 @@ +// Copyright 2009 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// +// System calls and other sys.stuff for 386, Linux +// + +#include "zasm_GOOS_GOARCH.h" +#include "textflag.h" + +TEXT runtime·exit(SB),NOSPLIT,$0 + MOVL $252, AX // syscall number + MOVL code+0(FP), BX + CALL *runtime·_vdso(SB) + INT $3 // not reached + RET + +TEXT runtime·exit1(SB),NOSPLIT,$0 + MOVL $1, AX // exit - exit the current os thread + MOVL code+0(FP), BX + CALL *runtime·_vdso(SB) + INT $3 // not reached + RET + +TEXT runtime·open(SB),NOSPLIT,$0 + MOVL $5, AX // syscall - open + MOVL name+0(FP), BX + MOVL mode+4(FP), CX + MOVL perm+8(FP), DX + CALL *runtime·_vdso(SB) + MOVL AX, ret+12(FP) + RET + +TEXT runtime·close(SB),NOSPLIT,$0 + MOVL $6, AX // syscall - close + MOVL fd+0(FP), BX + CALL *runtime·_vdso(SB) + MOVL AX, ret+4(FP) + RET + +TEXT runtime·write(SB),NOSPLIT,$0 + MOVL $4, AX // syscall - write + MOVL fd+0(FP), BX + MOVL p+4(FP), CX + MOVL n+8(FP), DX + CALL *runtime·_vdso(SB) + MOVL AX, ret+12(FP) + RET + +TEXT runtime·read(SB),NOSPLIT,$0 + MOVL $3, AX // syscall - read + MOVL fd+0(FP), BX + MOVL p+4(FP), CX + MOVL n+8(FP), DX + CALL *runtime·_vdso(SB) + MOVL AX, ret+12(FP) + RET + +TEXT runtime·getrlimit(SB),NOSPLIT,$0 + MOVL $191, AX // syscall - ugetrlimit + MOVL kind+0(FP), BX + MOVL limit+4(FP), CX + CALL *runtime·_vdso(SB) + MOVL AX, ret+8(FP) + RET + +TEXT runtime·usleep(SB),NOSPLIT,$8 + MOVL $0, DX + MOVL usec+0(FP), AX + MOVL $1000000, CX + DIVL CX + MOVL AX, 0(SP) + MOVL DX, 4(SP) + + // select(0, 0, 0, 0, &tv) + MOVL $142, AX + MOVL $0, BX + MOVL $0, CX + MOVL $0, DX + MOVL $0, SI + LEAL 0(SP), DI + CALL *runtime·_vdso(SB) + RET + +TEXT runtime·raise(SB),NOSPLIT,$12 + MOVL $224, AX // syscall - gettid + CALL *runtime·_vdso(SB) + MOVL AX, BX // arg 1 tid + MOVL sig+0(FP), CX // arg 2 signal + MOVL $238, AX // syscall - tkill + CALL *runtime·_vdso(SB) + RET + +TEXT runtime·setitimer(SB),NOSPLIT,$0-12 + MOVL $104, AX // syscall - setitimer + MOVL mode+0(FP), BX + MOVL new+4(FP), CX + MOVL old+8(FP), DX + CALL *runtime·_vdso(SB) + RET + +TEXT runtime·mincore(SB),NOSPLIT,$0-16 + MOVL $218, AX // syscall - mincore + MOVL addr+0(FP), BX + MOVL n+4(FP), CX + MOVL dst+8(FP), DX + CALL *runtime·_vdso(SB) + MOVL AX, ret+12(FP) + RET + +// func now() (sec int64, nsec int32) +TEXT time·now(SB), NOSPLIT, $32 + MOVL $265, AX // syscall - clock_gettime + MOVL $0, BX // CLOCK_REALTIME + LEAL 8(SP), CX + MOVL $0, DX + CALL *runtime·_vdso(SB) + MOVL 8(SP), AX // sec + MOVL 12(SP), BX // nsec + + // sec is in AX, nsec in BX + MOVL AX, sec+0(FP) + MOVL $0, sec+4(FP) + MOVL BX, nsec+8(FP) + RET + +// int64 nanotime(void) so really +// void nanotime(int64 *nsec) +TEXT runtime·nanotime(SB), NOSPLIT, $32 + MOVL $265, AX // syscall - clock_gettime + MOVL $1, BX // CLOCK_MONOTONIC + LEAL 8(SP), CX + MOVL $0, DX + CALL *runtime·_vdso(SB) + MOVL 8(SP), AX // sec + MOVL 12(SP), BX // nsec + + // sec is in AX, nsec in BX + // convert to DX:AX nsec + MOVL $1000000000, CX + MULL CX + ADDL BX, AX + ADCL $0, DX + + MOVL AX, ret_lo+0(FP) + MOVL DX, ret_hi+4(FP) + RET + +TEXT runtime·rtsigprocmask(SB),NOSPLIT,$0 + MOVL $175, AX // syscall entry + MOVL sig+0(FP), BX + MOVL new+4(FP), CX + MOVL old+8(FP), DX + MOVL size+12(FP), SI + CALL *runtime·_vdso(SB) + CMPL AX, $0xfffff001 + JLS 2(PC) + INT $3 + RET + +TEXT runtime·rt_sigaction(SB),NOSPLIT,$0 + MOVL $174, AX // syscall - rt_sigaction + MOVL sig+0(FP), BX + MOVL new+4(FP), CX + MOVL old+8(FP), DX + MOVL size+12(FP), SI + CALL *runtime·_vdso(SB) + MOVL AX, ret+16(FP) + RET + +TEXT runtime·sigtramp(SB),NOSPLIT,$44 + get_tls(CX) + + // check that g exists + MOVL g(CX), DI + CMPL DI, $0 + JNE 6(PC) + MOVL sig+0(FP), BX + MOVL BX, 0(SP) + MOVL $runtime·badsignal(SB), AX + CALL AX + RET + + // save g + MOVL DI, 20(SP) + + // g = m->gsignal + MOVL g_m(DI), BX + MOVL m_gsignal(BX), BX + MOVL BX, g(CX) + + // copy arguments for call to sighandler + MOVL sig+0(FP), BX + MOVL BX, 0(SP) + MOVL info+4(FP), BX + MOVL BX, 4(SP) + MOVL context+8(FP), BX + MOVL BX, 8(SP) + MOVL DI, 12(SP) + + CALL runtime·sighandler(SB) + + // restore g + get_tls(CX) + MOVL 20(SP), BX + MOVL BX, g(CX) + + RET + +TEXT runtime·sigreturn(SB),NOSPLIT,$0 + MOVL $173, AX // rt_sigreturn + // Sigreturn expects same SP as signal handler, + // so cannot CALL *runtime._vsdo(SB) here. + INT $0x80 + INT $3 // not reached + RET + +TEXT runtime·mmap(SB),NOSPLIT,$0 + MOVL $192, AX // mmap2 + MOVL addr+0(FP), BX + MOVL n+4(FP), CX + MOVL prot+8(FP), DX + MOVL flags+12(FP), SI + MOVL fd+16(FP), DI + MOVL off+20(FP), BP + SHRL $12, BP + CALL *runtime·_vdso(SB) + CMPL AX, $0xfffff001 + JLS 3(PC) + NOTL AX + INCL AX + MOVL AX, ret+24(FP) + RET + +TEXT runtime·munmap(SB),NOSPLIT,$0 + MOVL $91, AX // munmap + MOVL addr+0(FP), BX + MOVL n+4(FP), CX + CALL *runtime·_vdso(SB) + CMPL AX, $0xfffff001 + JLS 2(PC) + INT $3 + RET + +TEXT runtime·madvise(SB),NOSPLIT,$0 + MOVL $219, AX // madvise + MOVL addr+0(FP), BX + MOVL n+4(FP), CX + MOVL flags+8(FP), DX + CALL *runtime·_vdso(SB) + // ignore failure - maybe pages are locked + RET + +// int32 futex(int32 *uaddr, int32 op, int32 val, +// struct timespec *timeout, int32 *uaddr2, int32 val2); +TEXT runtime·futex(SB),NOSPLIT,$0 + MOVL $240, AX // futex + MOVL addr+0(FP), BX + MOVL op+4(FP), CX + MOVL val+8(FP), DX + MOVL ts+12(FP), SI + MOVL addr2+16(FP), DI + MOVL val3+20(FP), BP + CALL *runtime·_vdso(SB) + MOVL AX, ret+24(FP) + RET + +// int32 clone(int32 flags, void *stack, M *mp, G *gp, void (*fn)(void)); +TEXT runtime·clone(SB),NOSPLIT,$0 + MOVL $120, AX // clone + MOVL flags+4(SP), BX + MOVL stack+8(SP), CX + MOVL $0, DX // parent tid ptr + MOVL $0, DI // child tid ptr + + // Copy mp, gp, fn off parent stack for use by child. + SUBL $16, CX + MOVL mm+12(SP), SI + MOVL SI, 0(CX) + MOVL gg+16(SP), SI + MOVL SI, 4(CX) + MOVL fn+20(SP), SI + MOVL SI, 8(CX) + MOVL $1234, 12(CX) + + // cannot use CALL *runtime·_vdso(SB) here, because + // the stack changes during the system call (after + // CALL *runtime·_vdso(SB), the child is still using + // the parent's stack when executing its RET instruction). + INT $0x80 + + // In parent, return. + CMPL AX, $0 + JEQ 3(PC) + MOVL AX, ret+20(FP) + RET + + // Paranoia: check that SP is as we expect. + MOVL mm+8(FP), BP + CMPL BP, $1234 + JEQ 2(PC) + INT $3 + + // Initialize AX to Linux tid + MOVL $224, AX + CALL *runtime·_vdso(SB) + + // In child on new stack. Reload registers (paranoia). + MOVL 0(SP), BX // m + MOVL flags+0(FP), DX // g + MOVL stk+4(FP), SI // fn + + MOVL AX, m_procid(BX) // save tid as m->procid + + // set up ldt 7+id to point at m->tls. + // newosproc left the id in tls[0]. + LEAL m_tls(BX), BP + MOVL 0(BP), DI + ADDL $7, DI // m0 is LDT#7. count up. + // setldt(tls#, &tls, sizeof tls) + PUSHAL // save registers + PUSHL $32 // sizeof tls + PUSHL BP // &tls + PUSHL DI // tls # + CALL runtime·setldt(SB) + POPL AX + POPL AX + POPL AX + POPAL + + // Now segment is established. Initialize m, g. + get_tls(AX) + MOVL DX, g(AX) + MOVL BX, g_m(DX) + + CALL runtime·stackcheck(SB) // smashes AX, CX + MOVL 0(DX), DX // paranoia; check they are not nil + MOVL 0(BX), BX + + // more paranoia; check that stack splitting code works + PUSHAL + CALL runtime·emptyfunc(SB) + POPAL + + CALL SI // fn() + CALL runtime·exit1(SB) + MOVL $0x1234, 0x1005 + +TEXT runtime·sigaltstack(SB),NOSPLIT,$-8 + MOVL $186, AX // sigaltstack + MOVL new+4(SP), BX + MOVL old+8(SP), CX + CALL *runtime·_vdso(SB) + CMPL AX, $0xfffff001 + JLS 2(PC) + INT $3 + RET + +// <asm-i386/ldt.h> +// struct user_desc { +// unsigned int entry_number; +// unsigned long base_addr; +// unsigned int limit; +// unsigned int seg_32bit:1; +// unsigned int contents:2; +// unsigned int read_exec_only:1; +// unsigned int limit_in_pages:1; +// unsigned int seg_not_present:1; +// unsigned int useable:1; +// }; +#define SEG_32BIT 0x01 +// contents are the 2 bits 0x02 and 0x04. +#define CONTENTS_DATA 0x00 +#define CONTENTS_STACK 0x02 +#define CONTENTS_CODE 0x04 +#define READ_EXEC_ONLY 0x08 +#define LIMIT_IN_PAGES 0x10 +#define SEG_NOT_PRESENT 0x20 +#define USEABLE 0x40 + +// setldt(int entry, int address, int limit) +TEXT runtime·setldt(SB),NOSPLIT,$32 + MOVL entry+0(FP), BX // entry + MOVL address+4(FP), CX // base address + + /* + * When linking against the system libraries, + * we use its pthread_create and let it set up %gs + * for us. When we do that, the private storage + * we get is not at 0(GS), 4(GS), but -8(GS), -4(GS). + * To insulate the rest of the tool chain from this + * ugliness, 8l rewrites 0(TLS) into -8(GS) for us. + * To accommodate that rewrite, we translate + * the address here and bump the limit to 0xffffffff (no limit) + * so that -8(GS) maps to 0(address). + * Also, the final 0(GS) (current 8(CX)) has to point + * to itself, to mimic ELF. + */ + ADDL $0x8, CX // address + MOVL CX, 0(CX) + + // set up user_desc + LEAL 16(SP), AX // struct user_desc + MOVL BX, 0(AX) + MOVL CX, 4(AX) + MOVL $0xfffff, 8(AX) + MOVL $(SEG_32BIT|LIMIT_IN_PAGES|USEABLE|CONTENTS_DATA), 12(AX) // flag bits + + // call modify_ldt + MOVL $1, BX // func = 1 (write) + MOVL AX, CX // user_desc + MOVL $16, DX // sizeof(user_desc) + MOVL $123, AX // syscall - modify_ldt + CALL *runtime·_vdso(SB) + + // breakpoint on error + CMPL AX, $0xfffff001 + JLS 2(PC) + INT $3 + + // compute segment selector - (entry*8+7) + MOVL entry+0(FP), AX + SHLL $3, AX + ADDL $7, AX + MOVW AX, GS + + RET + +TEXT runtime·osyield(SB),NOSPLIT,$0 + MOVL $158, AX + CALL *runtime·_vdso(SB) + RET + +TEXT runtime·sched_getaffinity(SB),NOSPLIT,$0 + MOVL $242, AX // syscall - sched_getaffinity + MOVL pid+0(FP), BX + MOVL len+4(FP), CX + MOVL buf+8(FP), DX + CALL *runtime·_vdso(SB) + MOVL AX, ret+12(FP) + RET + +// int32 runtime·epollcreate(int32 size); +TEXT runtime·epollcreate(SB),NOSPLIT,$0 + MOVL $254, AX + MOVL size+0(FP), BX + CALL *runtime·_vdso(SB) + MOVL AX, ret+4(FP) + RET + +// int32 runtime·epollcreate1(int32 flags); +TEXT runtime·epollcreate1(SB),NOSPLIT,$0 + MOVL $329, AX + MOVL flags+0(FP), BX + CALL *runtime·_vdso(SB) + MOVL AX, ret+4(FP) + RET + +// func epollctl(epfd, op, fd int32, ev *epollEvent) int +TEXT runtime·epollctl(SB),NOSPLIT,$0 + MOVL $255, AX + MOVL epfd+0(FP), BX + MOVL op+4(FP), CX + MOVL fd+8(FP), DX + MOVL ev+12(FP), SI + CALL *runtime·_vdso(SB) + MOVL AX, ret+16(FP) + RET + +// int32 runtime·epollwait(int32 epfd, EpollEvent *ev, int32 nev, int32 timeout); +TEXT runtime·epollwait(SB),NOSPLIT,$0 + MOVL $256, AX + MOVL epfd+0(FP), BX + MOVL ev+4(FP), CX + MOVL nev+8(FP), DX + MOVL timeout+12(FP), SI + CALL *runtime·_vdso(SB) + MOVL AX, ret+16(FP) + RET + +// void runtime·closeonexec(int32 fd); +TEXT runtime·closeonexec(SB),NOSPLIT,$0 + MOVL $55, AX // fcntl + MOVL fd+0(FP), BX // fd + MOVL $2, CX // F_SETFD + MOVL $1, DX // FD_CLOEXEC + CALL *runtime·_vdso(SB) + RET |