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-rw-r--r--src/pkg/runtime/linux/386/sys.s344
1 files changed, 344 insertions, 0 deletions
diff --git a/src/pkg/runtime/linux/386/sys.s b/src/pkg/runtime/linux/386/sys.s
new file mode 100644
index 000000000..0b4a34986
--- /dev/null
+++ b/src/pkg/runtime/linux/386/sys.s
@@ -0,0 +1,344 @@
+// 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 "386/asm.h"
+
+TEXT runtime·exit(SB),7,$0
+ MOVL $252, AX // syscall number
+ MOVL 4(SP), BX
+ INT $0x80
+ INT $3 // not reached
+ RET
+
+TEXT runtime·exit1(SB),7,$0
+ MOVL $1, AX // exit - exit the current os thread
+ MOVL 4(SP), BX
+ INT $0x80
+ INT $3 // not reached
+ RET
+
+TEXT runtime·open(SB),7,$0
+ MOVL $5, AX // syscall - open
+ MOVL 4(SP), BX
+ MOVL 8(SP), CX
+ MOVL 12(SP), DX
+ INT $0x80
+ RET
+
+TEXT runtime·close(SB),7,$0
+ MOVL $6, AX // syscall - close
+ MOVL 4(SP), BX
+ INT $0x80
+ RET
+
+TEXT runtime·write(SB),7,$0
+ MOVL $4, AX // syscall - write
+ MOVL 4(SP), BX
+ MOVL 8(SP), CX
+ MOVL 12(SP), DX
+ INT $0x80
+ RET
+
+TEXT runtime·read(SB),7,$0
+ MOVL $3, AX // syscall - read
+ MOVL 4(SP), BX
+ MOVL 8(SP), CX
+ MOVL 12(SP), DX
+ INT $0x80
+ RET
+
+TEXT runtime·raisesigpipe(SB),7,$12
+ MOVL $224, AX // syscall - gettid
+ INT $0x80
+ MOVL AX, 0(SP) // arg 1 tid
+ MOVL $13, 4(SP) // arg 2 SIGPIPE
+ MOVL $238, AX // syscall - tkill
+ INT $0x80
+ RET
+
+TEXT runtime·setitimer(SB),7,$0-24
+ MOVL $104, AX // syscall - setitimer
+ MOVL 4(SP), BX
+ MOVL 8(SP), CX
+ MOVL 12(SP), DX
+ INT $0x80
+ RET
+
+TEXT runtime·mincore(SB),7,$0-24
+ MOVL $218, AX // syscall - mincore
+ MOVL 4(SP), BX
+ MOVL 8(SP), CX
+ MOVL 12(SP), DX
+ INT $0x80
+ RET
+
+TEXT runtime·gettime(SB), 7, $32
+ MOVL $78, AX // syscall - gettimeofday
+ LEAL 8(SP), BX
+ MOVL $0, CX
+ MOVL $0, DX
+ INT $0x80
+
+ MOVL 8(SP), BX // sec
+ MOVL sec+0(FP), DI
+ MOVL BX, (DI)
+ MOVL $0, 4(DI) // zero extend 32 -> 64 bits
+
+ MOVL 12(SP), BX // usec
+ MOVL usec+4(FP), DI
+ MOVL BX, (DI)
+ RET
+
+TEXT runtime·rt_sigaction(SB),7,$0
+ MOVL $174, AX // syscall - rt_sigaction
+ MOVL 4(SP), BX
+ MOVL 8(SP), CX
+ MOVL 12(SP), DX
+ MOVL 16(SP), SI
+ INT $0x80
+ RET
+
+TEXT runtime·sigtramp(SB),7,$44
+ get_tls(CX)
+
+ // save g
+ MOVL g(CX), DI
+ MOVL DI, 20(SP)
+
+ // g = m->gsignal
+ MOVL m(CX), 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·sigignore(SB),7,$0
+ RET
+
+TEXT runtime·sigreturn(SB),7,$0
+ MOVL $173, AX // rt_sigreturn
+ INT $0x80
+ INT $3 // not reached
+ RET
+
+TEXT runtime·mmap(SB),7,$0
+ MOVL $192, AX // mmap2
+ MOVL 4(SP), BX
+ MOVL 8(SP), CX
+ MOVL 12(SP), DX
+ MOVL 16(SP), SI
+ MOVL 20(SP), DI
+ MOVL 24(SP), BP
+ SHRL $12, BP
+ INT $0x80
+ CMPL AX, $0xfffff001
+ JLS 3(PC)
+ NOTL AX
+ INCL AX
+ RET
+
+TEXT runtime·munmap(SB),7,$0
+ MOVL $91, AX // munmap
+ MOVL 4(SP), BX
+ MOVL 8(SP), CX
+ INT $0x80
+ CMPL AX, $0xfffff001
+ JLS 2(PC)
+ INT $3
+ RET
+
+// int32 futex(int32 *uaddr, int32 op, int32 val,
+// struct timespec *timeout, int32 *uaddr2, int32 val2);
+TEXT runtime·futex(SB),7,$0
+ MOVL $240, AX // futex
+ MOVL 4(SP), BX
+ MOVL 8(SP), CX
+ MOVL 12(SP), DX
+ MOVL 16(SP), SI
+ MOVL 20(SP), DI
+ MOVL 24(SP), BP
+ INT $0x80
+ RET
+
+// int32 clone(int32 flags, void *stack, M *m, G *g, void (*fn)(void));
+TEXT runtime·clone(SB),7,$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 m, g, 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)
+
+ INT $0x80
+
+ // In parent, return.
+ CMPL AX, $0
+ JEQ 2(PC)
+ RET
+
+ // Paranoia: check that SP is as we expect.
+ MOVL 12(SP), BP
+ CMPL BP, $1234
+ JEQ 2(PC)
+ INT $3
+
+ // Initialize AX to Linux tid
+ MOVL $224, AX
+ INT $0x80
+
+ // In child on new stack. Reload registers (paranoia).
+ MOVL 0(SP), BX // m
+ MOVL 4(SP), DX // g
+ MOVL 8(SP), 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, m(AX)
+
+ 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 $0x1234, 0x1005
+ RET
+
+TEXT runtime·sigaltstack(SB),7,$-8
+ MOVL $186, AX // sigaltstack
+ MOVL new+4(SP), BX
+ MOVL old+8(SP), CX
+ INT $0x80
+ 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),7,$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(GS) 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
+ INT $0x80
+
+ // 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),7,$0
+ MOVL $158, AX
+ INT $0x80
+ RET
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