diff options
Diffstat (limited to 'arch/x86/include/asm/syscall.h')
| -rw-r--r-- | arch/x86/include/asm/syscall.h | 135 |
1 files changed, 135 insertions, 0 deletions
diff --git a/arch/x86/include/asm/syscall.h b/arch/x86/include/asm/syscall.h new file mode 100644 index 000000000..5b85987a5 --- /dev/null +++ b/arch/x86/include/asm/syscall.h @@ -0,0 +1,135 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Access to user system call parameters and results + * + * Copyright (C) 2008-2009 Red Hat, Inc. All rights reserved. + * + * See asm-generic/syscall.h for descriptions of what we must do here. + */ + +#ifndef _ASM_X86_SYSCALL_H +#define _ASM_X86_SYSCALL_H + +#include <uapi/linux/audit.h> +#include <linux/sched.h> +#include <linux/err.h> +#include <asm/thread_info.h> /* for TS_COMPAT */ +#include <asm/unistd.h> + +typedef long (*sys_call_ptr_t)(const struct pt_regs *); +extern const sys_call_ptr_t sys_call_table[]; + +#if defined(CONFIG_X86_32) +#define ia32_sys_call_table sys_call_table +#else +/* + * These may not exist, but still put the prototypes in so we + * can use IS_ENABLED(). + */ +extern const sys_call_ptr_t ia32_sys_call_table[]; +extern const sys_call_ptr_t x32_sys_call_table[]; +#endif + +/* + * Only the low 32 bits of orig_ax are meaningful, so we return int. + * This importantly ignores the high bits on 64-bit, so comparisons + * sign-extend the low 32 bits. + */ +static inline int syscall_get_nr(struct task_struct *task, struct pt_regs *regs) +{ + return regs->orig_ax; +} + +static inline void syscall_rollback(struct task_struct *task, + struct pt_regs *regs) +{ + regs->ax = regs->orig_ax; +} + +static inline long syscall_get_error(struct task_struct *task, + struct pt_regs *regs) +{ + unsigned long error = regs->ax; +#ifdef CONFIG_IA32_EMULATION + /* + * TS_COMPAT is set for 32-bit syscall entries and then + * remains set until we return to user mode. + */ + if (task->thread_info.status & (TS_COMPAT|TS_I386_REGS_POKED)) + /* + * Sign-extend the value so (int)-EFOO becomes (long)-EFOO + * and will match correctly in comparisons. + */ + error = (long) (int) error; +#endif + return IS_ERR_VALUE(error) ? error : 0; +} + +static inline long syscall_get_return_value(struct task_struct *task, + struct pt_regs *regs) +{ + return regs->ax; +} + +static inline void syscall_set_return_value(struct task_struct *task, + struct pt_regs *regs, + int error, long val) +{ + regs->ax = (long) error ?: val; +} + +#ifdef CONFIG_X86_32 + +static inline void syscall_get_arguments(struct task_struct *task, + struct pt_regs *regs, + unsigned long *args) +{ + memcpy(args, ®s->bx, 6 * sizeof(args[0])); +} + +static inline int syscall_get_arch(struct task_struct *task) +{ + return AUDIT_ARCH_I386; +} + +#else /* CONFIG_X86_64 */ + +static inline void syscall_get_arguments(struct task_struct *task, + struct pt_regs *regs, + unsigned long *args) +{ +# ifdef CONFIG_IA32_EMULATION + if (task->thread_info.status & TS_COMPAT) { + *args++ = regs->bx; + *args++ = regs->cx; + *args++ = regs->dx; + *args++ = regs->si; + *args++ = regs->di; + *args = regs->bp; + } else +# endif + { + *args++ = regs->di; + *args++ = regs->si; + *args++ = regs->dx; + *args++ = regs->r10; + *args++ = regs->r8; + *args = regs->r9; + } +} + +static inline int syscall_get_arch(struct task_struct *task) +{ + /* x32 tasks should be considered AUDIT_ARCH_X86_64. */ + return (IS_ENABLED(CONFIG_IA32_EMULATION) && + task->thread_info.status & TS_COMPAT) + ? AUDIT_ARCH_I386 : AUDIT_ARCH_X86_64; +} + +void do_syscall_64(struct pt_regs *regs, int nr); +void do_int80_syscall_32(struct pt_regs *regs); +long do_fast_syscall_32(struct pt_regs *regs); + +#endif /* CONFIG_X86_32 */ + +#endif /* _ASM_X86_SYSCALL_H */ |