| /* |
| * This file is subject to the terms and conditions of the GNU General Public |
| * License. See the file "COPYING" in the main directory of this archive |
| * for more details. |
| * |
| * Copyright (C) 1995 - 2000, 2001 by Ralf Baechle |
| * Copyright (C) 1999, 2000 Silicon Graphics, Inc. |
| * Copyright (C) 2001 MIPS Technologies, Inc. |
| * Copyright (C) 2004 Thiemo Seufer |
| * |
| * Hairy, the userspace application uses a different argument passing |
| * convention than the kernel, so we have to translate things from o32 |
| * to ABI64 calling convention. 64-bit syscalls are also processed |
| * here for now. |
| */ |
| #include <linux/errno.h> |
| #include <asm/asm.h> |
| #include <asm/asmmacro.h> |
| #include <asm/irqflags.h> |
| #include <asm/mipsregs.h> |
| #include <asm/regdef.h> |
| #include <asm/stackframe.h> |
| #include <asm/thread_info.h> |
| #include <asm/unistd.h> |
| #include <asm/sysmips.h> |
| |
| .align 5 |
| NESTED(handle_sys, PT_SIZE, sp) |
| .set noat |
| SAVE_SOME |
| TRACE_IRQS_ON_RELOAD |
| STI |
| .set at |
| ld t1, PT_EPC(sp) # skip syscall on return |
| |
| dsubu t0, v0, __NR_O32_Linux # check syscall number |
| sltiu t0, t0, __NR_O32_Linux_syscalls |
| daddiu t1, 4 # skip to next instruction |
| sd t1, PT_EPC(sp) |
| beqz t0, not_o32_scall |
| #if 0 |
| SAVE_ALL |
| move a1, v0 |
| ASM_PRINT("Scall %ld\n") |
| RESTORE_ALL |
| #endif |
| |
| /* We don't want to stumble over broken sign extensions from |
| userland. O32 does never use the upper half. */ |
| sll a0, a0, 0 |
| sll a1, a1, 0 |
| sll a2, a2, 0 |
| sll a3, a3, 0 |
| |
| sd a3, PT_R26(sp) # save a3 for syscall restarting |
| |
| /* |
| * More than four arguments. Try to deal with it by copying the |
| * stack arguments from the user stack to the kernel stack. |
| * This Sucks (TM). |
| * |
| * We intentionally keep the kernel stack a little below the top of |
| * userspace so we don't have to do a slower byte accurate check here. |
| */ |
| ld t0, PT_R29(sp) # get old user stack pointer |
| daddu t1, t0, 32 |
| bltz t1, bad_stack |
| |
| load_a4: lw a4, 16(t0) # argument #5 from usp |
| load_a5: lw a5, 20(t0) # argument #6 from usp |
| load_a6: lw a6, 24(t0) # argument #7 from usp |
| load_a7: lw a7, 28(t0) # argument #8 from usp |
| loads_done: |
| |
| .section __ex_table,"a" |
| PTR_WD load_a4, bad_stack_a4 |
| PTR_WD load_a5, bad_stack_a5 |
| PTR_WD load_a6, bad_stack_a6 |
| PTR_WD load_a7, bad_stack_a7 |
| .previous |
| |
| /* |
| * absolute syscall number is in v0 unless we called syscall(__NR_###) |
| * where the real syscall number is in a0 |
| * note: NR_syscall is the first O32 syscall but the macro is |
| * only defined when compiling with -mabi=32 (CONFIG_32BIT) |
| * therefore __NR_O32_Linux is used (4000) |
| */ |
| |
| subu t2, v0, __NR_O32_Linux |
| bnez t2, 1f /* __NR_syscall at offset 0 */ |
| LONG_S a0, TI_SYSCALL($28) # Save a0 as syscall number |
| b 2f |
| 1: |
| LONG_S v0, TI_SYSCALL($28) # Save v0 as syscall number |
| 2: |
| |
| li t1, _TIF_WORK_SYSCALL_ENTRY |
| LONG_L t0, TI_FLAGS($28) # syscall tracing enabled? |
| and t0, t1, t0 |
| bnez t0, trace_a_syscall |
| |
| syscall_common: |
| dsll t0, v0, 3 # offset into table |
| ld t2, (sys32_call_table - (__NR_O32_Linux * 8))(t0) |
| |
| jalr t2 # Do The Real Thing (TM) |
| |
| li t0, -EMAXERRNO - 1 # error? |
| sltu t0, t0, v0 |
| sd t0, PT_R7(sp) # set error flag |
| beqz t0, 1f |
| |
| ld t1, PT_R2(sp) # syscall number |
| dnegu v0 # error |
| sd t1, PT_R0(sp) # save it for syscall restarting |
| 1: sd v0, PT_R2(sp) # result |
| |
| o32_syscall_exit: |
| j syscall_exit_partial |
| |
| /* ------------------------------------------------------------------------ */ |
| |
| trace_a_syscall: |
| SAVE_STATIC |
| sd a4, PT_R8(sp) # Save argument registers |
| sd a5, PT_R9(sp) |
| sd a6, PT_R10(sp) |
| sd a7, PT_R11(sp) # For indirect syscalls |
| |
| move a0, sp |
| jal syscall_trace_enter |
| |
| bltz v0, 1f # seccomp failed? Skip syscall |
| |
| RESTORE_STATIC |
| ld v0, PT_R2(sp) # Restore syscall (maybe modified) |
| ld a0, PT_R4(sp) # Restore argument registers |
| ld a1, PT_R5(sp) |
| ld a2, PT_R6(sp) |
| ld a3, PT_R7(sp) |
| ld a4, PT_R8(sp) |
| ld a5, PT_R9(sp) |
| ld a6, PT_R10(sp) |
| ld a7, PT_R11(sp) # For indirect syscalls |
| |
| dsubu t0, v0, __NR_O32_Linux # check (new) syscall number |
| sltiu t0, t0, __NR_O32_Linux_syscalls |
| beqz t0, not_o32_scall |
| |
| j syscall_common |
| |
| 1: j syscall_exit |
| |
| /* ------------------------------------------------------------------------ */ |
| |
| /* |
| * The stackpointer for a call with more than 4 arguments is bad. |
| */ |
| bad_stack: |
| li v0, EFAULT |
| sd v0, PT_R2(sp) |
| li t0, 1 # set error flag |
| sd t0, PT_R7(sp) |
| j o32_syscall_exit |
| |
| bad_stack_a4: |
| li a4, 0 |
| b load_a5 |
| |
| bad_stack_a5: |
| li a5, 0 |
| b load_a6 |
| |
| bad_stack_a6: |
| li a6, 0 |
| b load_a7 |
| |
| bad_stack_a7: |
| li a7, 0 |
| b loads_done |
| |
| not_o32_scall: |
| /* |
| * This is not an o32 compatibility syscall, pass it on |
| * to the 64-bit syscall handlers. |
| */ |
| #ifdef CONFIG_MIPS32_N32 |
| j handle_sysn32 |
| #else |
| j handle_sys64 |
| #endif |
| END(handle_sys) |
| |
| LEAF(sys32_syscall) |
| subu t0, a0, __NR_O32_Linux # check syscall number |
| sltiu v0, t0, __NR_O32_Linux_syscalls |
| beqz t0, einval # do not recurse |
| dsll t1, t0, 3 |
| beqz v0, einval |
| ld t2, sys32_call_table(t1) # syscall routine |
| |
| move a0, a1 # shift argument registers |
| move a1, a2 |
| move a2, a3 |
| move a3, a4 |
| move a4, a5 |
| move a5, a6 |
| move a6, a7 |
| jr t2 |
| /* Unreached */ |
| |
| einval: li v0, -ENOSYS |
| jr ra |
| END(sys32_syscall) |
| |
| #define __SYSCALL_WITH_COMPAT(nr, native, compat) __SYSCALL(nr, compat) |
| #define __SYSCALL(nr, entry) PTR_WD entry |
| .align 3 |
| .type sys32_call_table,@object |
| EXPORT(sys32_call_table) |
| #include <asm/syscall_table_o32.h> |
