diff options
Diffstat (limited to 'linux-user/host')
| -rw-r--r-- | linux-user/host/aarch64/hostdep.h | 38 | ||||
| -rw-r--r-- | linux-user/host/aarch64/safe-syscall.inc.S | 75 | ||||
| -rw-r--r-- | linux-user/host/arm/hostdep.h | 38 | ||||
| -rw-r--r-- | linux-user/host/arm/safe-syscall.inc.S | 90 | ||||
| -rw-r--r-- | linux-user/host/i386/hostdep.h | 38 | ||||
| -rw-r--r-- | linux-user/host/i386/safe-syscall.inc.S | 112 | ||||
| -rw-r--r-- | linux-user/host/ia64/hostdep.h (renamed from linux-user/host/generic/hostdep.h) | 7 | ||||
| -rw-r--r-- | linux-user/host/mips/hostdep.h | 15 | ||||
| -rw-r--r-- | linux-user/host/ppc/hostdep.h | 15 | ||||
| -rw-r--r-- | linux-user/host/ppc64/hostdep.h | 38 | ||||
| -rw-r--r-- | linux-user/host/ppc64/safe-syscall.inc.S | 92 | ||||
| -rw-r--r-- | linux-user/host/s390/hostdep.h | 15 | ||||
| -rw-r--r-- | linux-user/host/s390x/hostdep.h | 38 | ||||
| -rw-r--r-- | linux-user/host/s390x/safe-syscall.inc.S | 90 | ||||
| -rw-r--r-- | linux-user/host/sparc/hostdep.h | 15 | ||||
| -rw-r--r-- | linux-user/host/sparc64/hostdep.h | 15 | ||||
| -rw-r--r-- | linux-user/host/x32/hostdep.h | 15 | ||||
| -rw-r--r-- | linux-user/host/x86_64/safe-syscall.inc.S | 6 |
18 files changed, 743 insertions, 9 deletions
diff --git a/linux-user/host/aarch64/hostdep.h b/linux-user/host/aarch64/hostdep.h new file mode 100644 index 0000000000..b79eaf1811 --- /dev/null +++ b/linux-user/host/aarch64/hostdep.h @@ -0,0 +1,38 @@ +/* + * hostdep.h : things which are dependent on the host architecture + * + * * Written by Peter Maydell <peter.maydell@linaro.org> + * + * Copyright (C) 2016 Linaro Limited + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + +#ifndef QEMU_HOSTDEP_H +#define QEMU_HOSTDEP_H + +/* We have a safe-syscall.inc.S */ +#define HAVE_SAFE_SYSCALL + +#ifndef __ASSEMBLER__ + +/* These are defined by the safe-syscall.inc.S file */ +extern char safe_syscall_start[]; +extern char safe_syscall_end[]; + +/* Adjust the signal context to rewind out of safe-syscall if we're in it */ +static inline void rewind_if_in_safe_syscall(void *puc) +{ + struct ucontext *uc = puc; + __u64 *pcreg = &uc->uc_mcontext.pc; + + if (*pcreg > (uintptr_t)safe_syscall_start + && *pcreg < (uintptr_t)safe_syscall_end) { + *pcreg = (uintptr_t)safe_syscall_start; + } +} + +#endif /* __ASSEMBLER__ */ + +#endif diff --git a/linux-user/host/aarch64/safe-syscall.inc.S b/linux-user/host/aarch64/safe-syscall.inc.S new file mode 100644 index 0000000000..58a2329b37 --- /dev/null +++ b/linux-user/host/aarch64/safe-syscall.inc.S @@ -0,0 +1,75 @@ +/* + * safe-syscall.inc.S : host-specific assembly fragment + * to handle signals occurring at the same time as system calls. + * This is intended to be included by linux-user/safe-syscall.S + * + * Written by Richard Henderson <rth@twiddle.net> + * Copyright (C) 2016 Red Hat, Inc. + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + + .global safe_syscall_base + .global safe_syscall_start + .global safe_syscall_end + .type safe_syscall_base, #function + .type safe_syscall_start, #function + .type safe_syscall_end, #function + + /* This is the entry point for making a system call. The calling + * convention here is that of a C varargs function with the + * first argument an 'int *' to the signal_pending flag, the + * second one the system call number (as a 'long'), and all further + * arguments being syscall arguments (also 'long'). + * We return a long which is the syscall's return value, which + * may be negative-errno on failure. Conversion to the + * -1-and-errno-set convention is done by the calling wrapper. + */ +safe_syscall_base: + .cfi_startproc + /* The syscall calling convention isn't the same as the + * C one: + * we enter with x0 == *signal_pending + * x1 == syscall number + * x2 ... x7, (stack) == syscall arguments + * and return the result in x0 + * and the syscall instruction needs + * x8 == syscall number + * x0 ... x7 == syscall arguments + * and returns the result in x0 + * Shuffle everything around appropriately. + */ + mov x9, x0 /* signal_pending pointer */ + mov x8, x1 /* syscall number */ + mov x0, x2 /* syscall arguments */ + mov x1, x3 + mov x2, x4 + mov x3, x5 + mov x4, x6 + mov x6, x7 + ldr x7, [sp] + + /* This next sequence of code works in conjunction with the + * rewind_if_safe_syscall_function(). If a signal is taken + * and the interrupted PC is anywhere between 'safe_syscall_start' + * and 'safe_syscall_end' then we rewind it to 'safe_syscall_start'. + * The code sequence must therefore be able to cope with this, and + * the syscall instruction must be the final one in the sequence. + */ +safe_syscall_start: + /* if signal_pending is non-zero, don't do the call */ + ldr w10, [x9] + cbnz w10, 0f + svc 0x0 +safe_syscall_end: + /* code path for having successfully executed the syscall */ + ret + +0: + /* code path when we didn't execute the syscall */ + mov x0, #-TARGET_ERESTARTSYS + ret + .cfi_endproc + + .size safe_syscall_base, .-safe_syscall_base diff --git a/linux-user/host/arm/hostdep.h b/linux-user/host/arm/hostdep.h new file mode 100644 index 0000000000..8e1ff2ffc5 --- /dev/null +++ b/linux-user/host/arm/hostdep.h @@ -0,0 +1,38 @@ +/* + * hostdep.h : things which are dependent on the host architecture + * + * * Written by Peter Maydell <peter.maydell@linaro.org> + * + * Copyright (C) 2016 Linaro Limited + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + +#ifndef QEMU_HOSTDEP_H +#define QEMU_HOSTDEP_H + +/* We have a safe-syscall.inc.S */ +#define HAVE_SAFE_SYSCALL + +#ifndef __ASSEMBLER__ + +/* These are defined by the safe-syscall.inc.S file */ +extern char safe_syscall_start[]; +extern char safe_syscall_end[]; + +/* Adjust the signal context to rewind out of safe-syscall if we're in it */ +static inline void rewind_if_in_safe_syscall(void *puc) +{ + struct ucontext *uc = puc; + unsigned long *pcreg = &uc->uc_mcontext.arm_pc; + + if (*pcreg > (uintptr_t)safe_syscall_start + && *pcreg < (uintptr_t)safe_syscall_end) { + *pcreg = (uintptr_t)safe_syscall_start; + } +} + +#endif /* __ASSEMBLER__ */ + +#endif diff --git a/linux-user/host/arm/safe-syscall.inc.S b/linux-user/host/arm/safe-syscall.inc.S new file mode 100644 index 0000000000..88c4958504 --- /dev/null +++ b/linux-user/host/arm/safe-syscall.inc.S @@ -0,0 +1,90 @@ +/* + * safe-syscall.inc.S : host-specific assembly fragment + * to handle signals occurring at the same time as system calls. + * This is intended to be included by linux-user/safe-syscall.S + * + * Written by Richard Henderson <rth@twiddle.net> + * Copyright (C) 2016 Red Hat, Inc. + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + + .global safe_syscall_base + .global safe_syscall_start + .global safe_syscall_end + .type safe_syscall_base, %function + + .cfi_sections .debug_frame + + .text + .syntax unified + .arm + .align 2 + + /* This is the entry point for making a system call. The calling + * convention here is that of a C varargs function with the + * first argument an 'int *' to the signal_pending flag, the + * second one the system call number (as a 'long'), and all further + * arguments being syscall arguments (also 'long'). + * We return a long which is the syscall's return value, which + * may be negative-errno on failure. Conversion to the + * -1-and-errno-set convention is done by the calling wrapper. + */ +safe_syscall_base: + .fnstart + .cfi_startproc + mov r12, sp /* save entry stack */ + push { r4, r5, r6, r7, r8, lr } + .save { r4, r5, r6, r7, r8, lr } + .cfi_adjust_cfa_offset 24 + .cfi_rel_offset r4, 0 + .cfi_rel_offset r5, 4 + .cfi_rel_offset r6, 8 + .cfi_rel_offset r7, 12 + .cfi_rel_offset r8, 16 + .cfi_rel_offset lr, 20 + + /* The syscall calling convention isn't the same as the C one: + * we enter with r0 == *signal_pending + * r1 == syscall number + * r2, r3, [sp+0] ... [sp+12] == syscall arguments + * and return the result in r0 + * and the syscall instruction needs + * r7 == syscall number + * r0 ... r6 == syscall arguments + * and returns the result in r0 + * Shuffle everything around appropriately. + * Note the 16 bytes that we pushed to save registers. + */ + mov r8, r0 /* copy signal_pending */ + mov r7, r1 /* syscall number */ + mov r0, r2 /* syscall args */ + mov r1, r3 + ldm r12, { r2, r3, r4, r5, r6 } + + /* This next sequence of code works in conjunction with the + * rewind_if_safe_syscall_function(). If a signal is taken + * and the interrupted PC is anywhere between 'safe_syscall_start' + * and 'safe_syscall_end' then we rewind it to 'safe_syscall_start'. + * The code sequence must therefore be able to cope with this, and + * the syscall instruction must be the final one in the sequence. + */ +safe_syscall_start: + /* if signal_pending is non-zero, don't do the call */ + ldr r12, [r8] /* signal_pending */ + tst r12, r12 + bne 1f + swi 0 +safe_syscall_end: + /* code path for having successfully executed the syscall */ + pop { r4, r5, r6, r7, r8, pc } + +1: + /* code path when we didn't execute the syscall */ + ldr r0, =-TARGET_ERESTARTSYS + pop { r4, r5, r6, r7, r8, pc } + .fnend + .cfi_endproc + + .size safe_syscall_base, .-safe_syscall_base diff --git a/linux-user/host/i386/hostdep.h b/linux-user/host/i386/hostdep.h new file mode 100644 index 0000000000..5a12f4adce --- /dev/null +++ b/linux-user/host/i386/hostdep.h @@ -0,0 +1,38 @@ +/* + * hostdep.h : things which are dependent on the host architecture + * + * * Written by Peter Maydell <peter.maydell@linaro.org> + * + * Copyright (C) 2016 Linaro Limited + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + +#ifndef QEMU_HOSTDEP_H +#define QEMU_HOSTDEP_H + +/* We have a safe-syscall.inc.S */ +#define HAVE_SAFE_SYSCALL + +#ifndef __ASSEMBLER__ + +/* These are defined by the safe-syscall.inc.S file */ +extern char safe_syscall_start[]; +extern char safe_syscall_end[]; + +/* Adjust the signal context to rewind out of safe-syscall if we're in it */ +static inline void rewind_if_in_safe_syscall(void *puc) +{ + struct ucontext *uc = puc; + greg_t *pcreg = &uc->uc_mcontext.gregs[REG_EIP]; + + if (*pcreg > (uintptr_t)safe_syscall_start + && *pcreg < (uintptr_t)safe_syscall_end) { + *pcreg = (uintptr_t)safe_syscall_start; + } +} + +#endif /* __ASSEMBLER__ */ + +#endif diff --git a/linux-user/host/i386/safe-syscall.inc.S b/linux-user/host/i386/safe-syscall.inc.S new file mode 100644 index 0000000000..766d0ded98 --- /dev/null +++ b/linux-user/host/i386/safe-syscall.inc.S @@ -0,0 +1,112 @@ +/* + * safe-syscall.inc.S : host-specific assembly fragment + * to handle signals occurring at the same time as system calls. + * This is intended to be included by linux-user/safe-syscall.S + * + * Written by Richard Henderson <rth@twiddle.net> + * Copyright (C) 2016 Red Hat, Inc. + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + + .global safe_syscall_base + .global safe_syscall_start + .global safe_syscall_end + .type safe_syscall_base, @function + + /* This is the entry point for making a system call. The calling + * convention here is that of a C varargs function with the + * first argument an 'int *' to the signal_pending flag, the + * second one the system call number (as a 'long'), and all further + * arguments being syscall arguments (also 'long'). + * We return a long which is the syscall's return value, which + * may be negative-errno on failure. Conversion to the + * -1-and-errno-set convention is done by the calling wrapper. + */ +safe_syscall_base: + .cfi_startproc + push %ebp + .cfi_adjust_cfa_offset 4 + .cfi_rel_offset ebp, 0 + push %esi + .cfi_adjust_cfa_offset 4 + .cfi_rel_offset esi, 0 + push %edi + .cfi_adjust_cfa_offset 4 + .cfi_rel_offset edi, 0 + push %ebx + .cfi_adjust_cfa_offset 4 + .cfi_rel_offset ebx, 0 + + /* The syscall calling convention isn't the same as the C one: + * we enter with 0(%esp) == return address + * 4(%esp) == *signal_pending + * 8(%esp) == syscall number + * 12(%esp) ... 32(%esp) == syscall arguments + * and return the result in eax + * and the syscall instruction needs + * eax == syscall number + * ebx, ecx, edx, esi, edi, ebp == syscall arguments + * and returns the result in eax + * Shuffle everything around appropriately. + * Note the 16 bytes that we pushed to save registers. + */ + mov 12+16(%esp), %ebx /* the syscall arguments */ + mov 16+16(%esp), %ecx + mov 20+16(%esp), %edx + mov 24+16(%esp), %esi + mov 28+16(%esp), %edi + mov 32+16(%esp), %ebp + + /* This next sequence of code works in conjunction with the + * rewind_if_safe_syscall_function(). If a signal is taken + * and the interrupted PC is anywhere between 'safe_syscall_start' + * and 'safe_syscall_end' then we rewind it to 'safe_syscall_start'. + * The code sequence must therefore be able to cope with this, and + * the syscall instruction must be the final one in the sequence. + */ +safe_syscall_start: + /* if signal_pending is non-zero, don't do the call */ + mov 4+16(%esp), %eax /* signal_pending */ + cmp $0, (%eax) + jnz 1f + mov 8+16(%esp), %eax /* syscall number */ + int $0x80 +safe_syscall_end: + /* code path for having successfully executed the syscall */ + pop %ebx + .cfi_remember_state + .cfi_def_cfa_offset -4 + .cfi_restore ebx + pop %edi + .cfi_def_cfa_offset -4 + .cfi_restore edi + pop %esi + .cfi_def_cfa_offset -4 + .cfi_restore esi + pop %ebp + .cfi_def_cfa_offset -4 + .cfi_restore ebp + ret + +1: + /* code path when we didn't execute the syscall */ + .cfi_restore_state + mov $-TARGET_ERESTARTSYS, %eax + pop %ebx + .cfi_def_cfa_offset -4 + .cfi_restore ebx + pop %edi + .cfi_def_cfa_offset -4 + .cfi_restore edi + pop %esi + .cfi_def_cfa_offset -4 + .cfi_restore esi + pop %ebp + .cfi_def_cfa_offset -4 + .cfi_restore ebp + ret + .cfi_endproc + + .size safe_syscall_base, .-safe_syscall_base diff --git a/linux-user/host/generic/hostdep.h b/linux-user/host/ia64/hostdep.h index cfabc3590b..7609bf5cd7 100644 --- a/linux-user/host/generic/hostdep.h +++ b/linux-user/host/ia64/hostdep.h @@ -1,6 +1,5 @@ /* - * hostdep.h : fallback generic version of header for things - * which are dependent on the host architecture + * hostdep.h : things which are dependent on the host architecture * * * Written by Peter Maydell <peter.maydell@linaro.org> * @@ -13,8 +12,4 @@ #ifndef QEMU_HOSTDEP_H #define QEMU_HOSTDEP_H -/* This is the fallback header which is only used if the host - * architecture doesn't provide one in linux-user/host/$ARCH. - */ - #endif diff --git a/linux-user/host/mips/hostdep.h b/linux-user/host/mips/hostdep.h new file mode 100644 index 0000000000..7609bf5cd7 --- /dev/null +++ b/linux-user/host/mips/hostdep.h @@ -0,0 +1,15 @@ +/* + * hostdep.h : things which are dependent on the host architecture + * + * * Written by Peter Maydell <peter.maydell@linaro.org> + * + * Copyright (C) 2016 Linaro Limited + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + +#ifndef QEMU_HOSTDEP_H +#define QEMU_HOSTDEP_H + +#endif diff --git a/linux-user/host/ppc/hostdep.h b/linux-user/host/ppc/hostdep.h new file mode 100644 index 0000000000..7609bf5cd7 --- /dev/null +++ b/linux-user/host/ppc/hostdep.h @@ -0,0 +1,15 @@ +/* + * hostdep.h : things which are dependent on the host architecture + * + * * Written by Peter Maydell <peter.maydell@linaro.org> + * + * Copyright (C) 2016 Linaro Limited + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + +#ifndef QEMU_HOSTDEP_H +#define QEMU_HOSTDEP_H + +#endif diff --git a/linux-user/host/ppc64/hostdep.h b/linux-user/host/ppc64/hostdep.h new file mode 100644 index 0000000000..310e7d1b73 --- /dev/null +++ b/linux-user/host/ppc64/hostdep.h @@ -0,0 +1,38 @@ +/* + * hostdep.h : things which are dependent on the host architecture + * + * * Written by Peter Maydell <peter.maydell@linaro.org> + * + * Copyright (C) 2016 Linaro Limited + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + +#ifndef QEMU_HOSTDEP_H +#define QEMU_HOSTDEP_H + +/* We have a safe-syscall.inc.S */ +#define HAVE_SAFE_SYSCALL + +#ifndef __ASSEMBLER__ + +/* These are defined by the safe-syscall.inc.S file */ +extern char safe_syscall_start[]; +extern char safe_syscall_end[]; + +/* Adjust the signal context to rewind out of safe-syscall if we're in it */ +static inline void rewind_if_in_safe_syscall(void *puc) +{ + struct ucontext *uc = puc; + unsigned long *pcreg = &uc->uc_mcontext.gp_regs[PT_NIP]; + + if (*pcreg > (uintptr_t)safe_syscall_start + && *pcreg < (uintptr_t)safe_syscall_end) { + *pcreg = (uintptr_t)safe_syscall_start; + } +} + +#endif /* __ASSEMBLER__ */ + +#endif diff --git a/linux-user/host/ppc64/safe-syscall.inc.S b/linux-user/host/ppc64/safe-syscall.inc.S new file mode 100644 index 0000000000..d30050a67c --- /dev/null +++ b/linux-user/host/ppc64/safe-syscall.inc.S @@ -0,0 +1,92 @@ +/* + * safe-syscall.inc.S : host-specific assembly fragment + * to handle signals occurring at the same time as system calls. + * This is intended to be included by linux-user/safe-syscall.S + * + * Written by Richard Henderson <rth@twiddle.net> + * Copyright (C) 2016 Red Hat, Inc. + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + + .global safe_syscall_base + .global safe_syscall_start + .global safe_syscall_end + .type safe_syscall_base, @function + + .text + + /* This is the entry point for making a system call. The calling + * convention here is that of a C varargs function with the + * first argument an 'int *' to the signal_pending flag, the + * second one the system call number (as a 'long'), and all further + * arguments being syscall arguments (also 'long'). + * We return a long which is the syscall's return value, which + * may be negative-errno on failure. Conversion to the + * -1-and-errno-set convention is done by the calling wrapper. + */ +#if _CALL_ELF == 2 +safe_syscall_base: + .cfi_startproc + .localentry safe_syscall_base,0 +#else + .section ".opd","aw" + .align 3 +safe_syscall_base: + .quad .L.safe_syscall_base,.TOC.@tocbase,0 + .previous +.L.safe_syscall_base: + .cfi_startproc +#endif + /* We enter with r3 == *signal_pending + * r4 == syscall number + * r5 ... r10 == syscall arguments + * and return the result in r3 + * and the syscall instruction needs + * r0 == syscall number + * r3 ... r8 == syscall arguments + * and returns the result in r3 + * Shuffle everything around appropriately. + */ + mr 11, 3 /* signal_pending */ + mr 0, 4 /* syscall number */ + mr 3, 5 /* syscall arguments */ + mr 4, 6 + mr 5, 7 + mr 6, 8 + mr 7, 9 + mr 8, 10 + + /* This next sequence of code works in conjunction with the + * rewind_if_safe_syscall_function(). If a signal is taken + * and the interrupted PC is anywhere between 'safe_syscall_start' + * and 'safe_syscall_end' then we rewind it to 'safe_syscall_start'. + * The code sequence must therefore be able to cope with this, and + * the syscall instruction must be the final one in the sequence. + */ +safe_syscall_start: + /* if signal_pending is non-zero, don't do the call */ + lwz 12, 0(11) + cmpwi 0, 12, 0 + bne- 0f + sc +safe_syscall_end: + /* code path when we did execute the syscall */ + bnslr+ + + /* syscall failed; return negative errno */ + neg 3, 3 + blr + + /* code path when we didn't execute the syscall */ +0: addi 3, 0, -TARGET_ERESTARTSYS + blr + .cfi_endproc + +#if _CALL_ELF == 2 + .size safe_syscall_base, .-safe_syscall_base +#else + .size safe_syscall_base, .-.L.safe_syscall_base + .size .L.safe_syscall_base, .-.L.safe_syscall_base +#endif diff --git a/linux-user/host/s390/hostdep.h b/linux-user/host/s390/hostdep.h new file mode 100644 index 0000000000..7609bf5cd7 --- /dev/null +++ b/linux-user/host/s390/hostdep.h @@ -0,0 +1,15 @@ +/* + * hostdep.h : things which are dependent on the host architecture + * + * * Written by Peter Maydell <peter.maydell@linaro.org> + * + * Copyright (C) 2016 Linaro Limited + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + +#ifndef QEMU_HOSTDEP_H +#define QEMU_HOSTDEP_H + +#endif diff --git a/linux-user/host/s390x/hostdep.h b/linux-user/host/s390x/hostdep.h new file mode 100644 index 0000000000..e95871c46a --- /dev/null +++ b/linux-user/host/s390x/hostdep.h @@ -0,0 +1,38 @@ +/* + * hostdep.h : things which are dependent on the host architecture + * + * * Written by Peter Maydell <peter.maydell@linaro.org> + * + * Copyright (C) 2016 Linaro Limited + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + +#ifndef QEMU_HOSTDEP_H +#define QEMU_HOSTDEP_H + +/* We have a safe-syscall.inc.S */ +#define HAVE_SAFE_SYSCALL + +#ifndef __ASSEMBLER__ + +/* These are defined by the safe-syscall.inc.S file */ +extern char safe_syscall_start[]; +extern char safe_syscall_end[]; + +/* Adjust the signal context to rewind out of safe-syscall if we're in it */ +static inline void rewind_if_in_safe_syscall(void *puc) +{ + struct ucontext *uc = puc; + unsigned long *pcreg = &uc->uc_mcontext.psw.addr; + + if (*pcreg > (uintptr_t)safe_syscall_start + && *pcreg < (uintptr_t)safe_syscall_end) { + *pcreg = (uintptr_t)safe_syscall_start; + } +} + +#endif /* __ASSEMBLER__ */ + +#endif diff --git a/linux-user/host/s390x/safe-syscall.inc.S b/linux-user/host/s390x/safe-syscall.inc.S new file mode 100644 index 0000000000..f1b446abf6 --- /dev/null +++ b/linux-user/host/s390x/safe-syscall.inc.S @@ -0,0 +1,90 @@ +/* + * safe-syscall.inc.S : host-specific assembly fragment + * to handle signals occurring at the same time as system calls. + * This is intended to be included by linux-user/safe-syscall.S + * + * Written by Richard Henderson <rth@twiddle.net> + * Copyright (C) 2016 Red Hat, Inc. + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + + .global safe_syscall_base + .global safe_syscall_start + .global safe_syscall_end + .type safe_syscall_base, @function + + /* This is the entry point for making a system call. The calling + * convention here is that of a C varargs function with the + * first argument an 'int *' to the signal_pending flag, the + * second one the system call number (as a 'long'), and all further + * arguments being syscall arguments (also 'long'). + * We return a long which is the syscall's return value, which + * may be negative-errno on failure. Conversion to the + * -1-and-errno-set convention is done by the calling wrapper. + */ +safe_syscall_base: + .cfi_startproc + stmg %r6,%r15,48(%r15) /* save all call-saved registers */ + .cfi_offset %r15,-40 + .cfi_offset %r14,-48 + .cfi_offset %r13,-56 + .cfi_offset %r12,-64 + .cfi_offset %r11,-72 + .cfi_offset %r10,-80 + .cfi_offset %r9,-88 + .cfi_offset %r8,-96 + .cfi_offset %r7,-104 + .cfi_offset %r6,-112 + lgr %r1,%r15 + lg %r0,8(%r15) /* load eos */ + aghi %r15,-160 + .cfi_adjust_cfa_offset 160 + stg %r1,0(%r15) /* store back chain */ + stg %r0,8(%r15) /* store eos */ + + /* The syscall calling convention isn't the same as the + * C one: + * we enter with r2 == *signal_pending + * r3 == syscall number + * r4, r5, r6, (stack) == syscall arguments + * and return the result in r2 + * and the syscall instruction needs + * r1 == syscall number + * r2 ... r7 == syscall arguments + * and returns the result in r2 + * Shuffle everything around appropriately. + */ + lgr %r8,%r2 /* signal_pending pointer */ + lgr %r1,%r3 /* syscall number */ + lgr %r2,%r4 /* syscall args */ + lgr %r3,%r5 + lgr %r4,%r6 + lmg %r5,%r7,320(%r15) + + /* This next sequence of code works in conjunction with the + * rewind_if_safe_syscall_function(). If a signal is taken + * and the interrupted PC is anywhere between 'safe_syscall_start' + * and 'safe_syscall_end' then we rewind it to 'safe_syscall_start'. + * The code sequence must therefore be able to cope with this, and + * the syscall instruction must be the final one in the sequence. + */ +safe_syscall_start: + /* if signal_pending is non-zero, don't do the call */ + lt %r0,0(%r8) + jne 2f + svc 0 +safe_syscall_end: + +1: lg %r15,0(%r15) /* load back chain */ + .cfi_remember_state + .cfi_adjust_cfa_offset -160 + lmg %r6,%r15,48(%r15) /* load saved registers */ + br %r14 + .cfi_restore_state +2: lghi %r2, -TARGET_ERESTARTSYS + j 1b + .cfi_endproc + + .size safe_syscall_base, .-safe_syscall_base diff --git a/linux-user/host/sparc/hostdep.h b/linux-user/host/sparc/hostdep.h new file mode 100644 index 0000000000..7609bf5cd7 --- /dev/null +++ b/linux-user/host/sparc/hostdep.h @@ -0,0 +1,15 @@ +/* + * hostdep.h : things which are dependent on the host architecture + * + * * Written by Peter Maydell <peter.maydell@linaro.org> + * + * Copyright (C) 2016 Linaro Limited + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + +#ifndef QEMU_HOSTDEP_H +#define QEMU_HOSTDEP_H + +#endif diff --git a/linux-user/host/sparc64/hostdep.h b/linux-user/host/sparc64/hostdep.h new file mode 100644 index 0000000000..7609bf5cd7 --- /dev/null +++ b/linux-user/host/sparc64/hostdep.h @@ -0,0 +1,15 @@ +/* + * hostdep.h : things which are dependent on the host architecture + * + * * Written by Peter Maydell <peter.maydell@linaro.org> + * + * Copyright (C) 2016 Linaro Limited + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + +#ifndef QEMU_HOSTDEP_H +#define QEMU_HOSTDEP_H + +#endif diff --git a/linux-user/host/x32/hostdep.h b/linux-user/host/x32/hostdep.h new file mode 100644 index 0000000000..7609bf5cd7 --- /dev/null +++ b/linux-user/host/x32/hostdep.h @@ -0,0 +1,15 @@ +/* + * hostdep.h : things which are dependent on the host architecture + * + * * Written by Peter Maydell <peter.maydell@linaro.org> + * + * Copyright (C) 2016 Linaro Limited + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + +#ifndef QEMU_HOSTDEP_H +#define QEMU_HOSTDEP_H + +#endif diff --git a/linux-user/host/x86_64/safe-syscall.inc.S b/linux-user/host/x86_64/safe-syscall.inc.S index e09368d450..f36992daa3 100644 --- a/linux-user/host/x86_64/safe-syscall.inc.S +++ b/linux-user/host/x86_64/safe-syscall.inc.S @@ -67,8 +67,8 @@ safe_syscall_base: */ safe_syscall_start: /* if signal_pending is non-zero, don't do the call */ - testl $1, (%rbp) - jnz return_ERESTARTSYS + cmpl $0, (%rbp) + jnz 1f syscall safe_syscall_end: /* code path for having successfully executed the syscall */ @@ -78,7 +78,7 @@ safe_syscall_end: .cfi_restore rbp ret -return_ERESTARTSYS: +1: /* code path when we didn't execute the syscall */ .cfi_restore_state mov $-TARGET_ERESTARTSYS, %rax |