diff options
Diffstat (limited to 'arch/x86/include/asm/syscall.h')
| -rw-r--r-- | arch/x86/include/asm/syscall.h | 213 | 
1 files changed, 213 insertions, 0 deletions
diff --git a/arch/x86/include/asm/syscall.h b/arch/x86/include/asm/syscall.h new file mode 100644 index 00000000000..d82f39bb790 --- /dev/null +++ b/arch/x86/include/asm/syscall.h @@ -0,0 +1,213 @@ +/* + * Access to user system call parameters and results + * + * Copyright (C) 2008 Red Hat, Inc.  All rights reserved. + * + * This copyrighted material is made available to anyone wishing to use, + * modify, copy, or redistribute it subject to the terms and conditions + * of the GNU General Public License v.2. + * + * See asm-generic/syscall.h for descriptions of what we must do here. + */ + +#ifndef _ASM_X86_SYSCALL_H +#define _ASM_X86_SYSCALL_H + +#include <linux/sched.h> +#include <linux/err.h> + +static inline long syscall_get_nr(struct task_struct *task, +				  struct pt_regs *regs) +{ +	/* +	 * We always sign-extend a -1 value being set here, +	 * so this is always either -1L or a syscall number. +	 */ +	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(task)->status & TS_COMPAT) +		/* +		 * 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 int i, unsigned int n, +					 unsigned long *args) +{ +	BUG_ON(i + n > 6); +	memcpy(args, ®s->bx + i, n * sizeof(args[0])); +} + +static inline void syscall_set_arguments(struct task_struct *task, +					 struct pt_regs *regs, +					 unsigned int i, unsigned int n, +					 const unsigned long *args) +{ +	BUG_ON(i + n > 6); +	memcpy(®s->bx + i, args, n * sizeof(args[0])); +} + +#else	 /* CONFIG_X86_64 */ + +static inline void syscall_get_arguments(struct task_struct *task, +					 struct pt_regs *regs, +					 unsigned int i, unsigned int n, +					 unsigned long *args) +{ +# ifdef CONFIG_IA32_EMULATION +	if (task_thread_info(task)->status & TS_COMPAT) +		switch (i) { +		case 0: +			if (!n--) break; +			*args++ = regs->bx; +		case 1: +			if (!n--) break; +			*args++ = regs->cx; +		case 2: +			if (!n--) break; +			*args++ = regs->dx; +		case 3: +			if (!n--) break; +			*args++ = regs->si; +		case 4: +			if (!n--) break; +			*args++ = regs->di; +		case 5: +			if (!n--) break; +			*args++ = regs->bp; +		case 6: +			if (!n--) break; +		default: +			BUG(); +			break; +		} +	else +# endif +		switch (i) { +		case 0: +			if (!n--) break; +			*args++ = regs->di; +		case 1: +			if (!n--) break; +			*args++ = regs->si; +		case 2: +			if (!n--) break; +			*args++ = regs->dx; +		case 3: +			if (!n--) break; +			*args++ = regs->r10; +		case 4: +			if (!n--) break; +			*args++ = regs->r8; +		case 5: +			if (!n--) break; +			*args++ = regs->r9; +		case 6: +			if (!n--) break; +		default: +			BUG(); +			break; +		} +} + +static inline void syscall_set_arguments(struct task_struct *task, +					 struct pt_regs *regs, +					 unsigned int i, unsigned int n, +					 const unsigned long *args) +{ +# ifdef CONFIG_IA32_EMULATION +	if (task_thread_info(task)->status & TS_COMPAT) +		switch (i) { +		case 0: +			if (!n--) break; +			regs->bx = *args++; +		case 1: +			if (!n--) break; +			regs->cx = *args++; +		case 2: +			if (!n--) break; +			regs->dx = *args++; +		case 3: +			if (!n--) break; +			regs->si = *args++; +		case 4: +			if (!n--) break; +			regs->di = *args++; +		case 5: +			if (!n--) break; +			regs->bp = *args++; +		case 6: +			if (!n--) break; +		default: +			BUG(); +			break; +		} +	else +# endif +		switch (i) { +		case 0: +			if (!n--) break; +			regs->di = *args++; +		case 1: +			if (!n--) break; +			regs->si = *args++; +		case 2: +			if (!n--) break; +			regs->dx = *args++; +		case 3: +			if (!n--) break; +			regs->r10 = *args++; +		case 4: +			if (!n--) break; +			regs->r8 = *args++; +		case 5: +			if (!n--) break; +			regs->r9 = *args++; +		case 6: +			if (!n--) break; +		default: +			BUG(); +			break; +		} +} + +#endif	/* CONFIG_X86_32 */ + +#endif	/* _ASM_X86_SYSCALL_H */  | 
