[mirror_ubuntu-focal-kernel.git] / arch / mips / include / asm / syscall.h

/*
 * Access to user system call parameters and results
 *
 * 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.
 *
 * See asm-generic/syscall.h for descriptions of what we must do here.
 *
 * Copyright (C) 2012 Ralf Baechle <ralf@linux-mips.org>
 */

#ifndef __ASM_MIPS_SYSCALL_H
#define __ASM_MIPS_SYSCALL_H

#include <linux/compiler.h>
#include <uapi/linux/audit.h>
#include <linux/elf-em.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/uaccess.h>
#include <asm/ptrace.h>
#include <asm/unistd.h>

#ifndef __NR_syscall /* Only defined if _MIPS_SIM == _MIPS_SIM_ABI32 */
#define __NR_syscall 4000
#endif

static inline bool mips_syscall_is_indirect(struct task_struct *task,
					    struct pt_regs *regs)
{
	/* O32 ABI syscall() - Either 64-bit with O32 or 32-bit */
	return (IS_ENABLED(CONFIG_32BIT) ||
		test_tsk_thread_flag(task, TIF_32BIT_REGS)) &&
		(regs->regs[2] == __NR_syscall);
}

static inline long syscall_get_nr(struct task_struct *task,
				  struct pt_regs *regs)
{
	return current_thread_info()->syscall;
}

static inline void mips_syscall_update_nr(struct task_struct *task,
					  struct pt_regs *regs)
{
	/*
	 * v0 is the system call number, except for O32 ABI syscall(), where it
	 * ends up in a0.
	 */
	if (mips_syscall_is_indirect(task, regs))
		task_thread_info(task)->syscall = regs->regs[4];
	else
		task_thread_info(task)->syscall = regs->regs[2];
}

static inline void mips_get_syscall_arg(unsigned long *arg,
	struct task_struct *task, struct pt_regs *regs, unsigned int n)
{
	unsigned long usp __maybe_unused = regs->regs[29];

	switch (n) {
	case 0: case 1: case 2: case 3:
		*arg = regs->regs[4 + n];

		return;

#ifdef CONFIG_32BIT
	case 4: case 5: case 6: case 7:
		get_user(*arg, (int *)usp + n);
		return;
#endif

#ifdef CONFIG_64BIT
	case 4: case 5: case 6: case 7:
#ifdef CONFIG_MIPS32_O32
		if (test_tsk_thread_flag(task, TIF_32BIT_REGS))
			get_user(*arg, (int *)usp + n);
		else
#endif
			*arg = regs->regs[4 + n];

		return;
#endif

	default:
		BUG();
	}

	unreachable();
}

static inline long syscall_get_error(struct task_struct *task,
				     struct pt_regs *regs)
{
	return regs->regs[7] ? -regs->regs[2] : 0;
}

static inline long syscall_get_return_value(struct task_struct *task,
					    struct pt_regs *regs)
{
	return regs->regs[2];
}

static inline void syscall_rollback(struct task_struct *task,
				    struct pt_regs *regs)
{
	/* Do nothing */
}

static inline void syscall_set_return_value(struct task_struct *task,
					    struct pt_regs *regs,
					    int error, long val)
{
	if (error) {
		regs->regs[2] = -error;
		regs->regs[7] = 1;
	} else {
		regs->regs[2] = val;
		regs->regs[7] = 0;
	}
}

static inline void syscall_get_arguments(struct task_struct *task,
					 struct pt_regs *regs,
					 unsigned long *args)
{
	unsigned int i = 0;
	unsigned int n = 6;

	/* O32 ABI syscall() */
	if (mips_syscall_is_indirect(task, regs))
		i++;

	while (n--)
		mips_get_syscall_arg(args++, task, regs, i++);
}

extern const unsigned long sys_call_table[];
extern const unsigned long sys32_call_table[];
extern const unsigned long sysn32_call_table[];

static inline int syscall_get_arch(struct task_struct *task)
{
	int arch = AUDIT_ARCH_MIPS;
#ifdef CONFIG_64BIT
	if (!test_tsk_thread_flag(task, TIF_32BIT_REGS)) {
		arch |= __AUDIT_ARCH_64BIT;
		/* N32 sets only TIF_32BIT_ADDR */
		if (test_tsk_thread_flag(task, TIF_32BIT_ADDR))
			arch |= __AUDIT_ARCH_CONVENTION_MIPS64_N32;
	}
#endif
#if defined(__LITTLE_ENDIAN)
	arch |=  __AUDIT_ARCH_LE;
#endif
	return arch;
}

#endif	/* __ASM_MIPS_SYSCALL_H */
Commit	Line	Data
19e2e172	1	/*
c0ff3c53 RB	2	* Access to user system call parameters and results
c0ff3c53 RB	3	*
19e2e172 RB	4	* This file is subject to the terms and conditions of the GNU General Public
	5	* License. See the file "COPYING" in the main directory of this archive
	6	* for more details.
	7	*
c0ff3c53 RB	8	* See asm-generic/syscall.h for descriptions of what we must do here.
c0ff3c53 RB	9	*
19e2e172 RB	10	* Copyright (C) 2012 Ralf Baechle <ralf@linux-mips.org>
	11	*/
	12
	13	#ifndef __ASM_MIPS_SYSCALL_H
	14	#define __ASM_MIPS_SYSCALL_H
	15
f5179287	16	#include <linux/compiler.h>
579ec9e1	17	#include <uapi/linux/audit.h>
bec9b2b2	18	#include <linux/elf-em.h>
c0ff3c53 RB	19	#include <linux/kernel.h>
	20	#include <linux/sched.h>
	21	#include <linux/uaccess.h>
	22	#include <asm/ptrace.h>
4c21b8fd MC	23	#include <asm/unistd.h>
	24
	25	#ifndef __NR_syscall /* Only defined if _MIPS_SIM == _MIPS_SIM_ABI32 */
	26	#define __NR_syscall 4000
	27	#endif
c0ff3c53	28
de8cd0dc JH	29	static inline bool mips_syscall_is_indirect(struct task_struct *task,
	30	struct pt_regs *regs)
	31	{
	32	/* O32 ABI syscall() - Either 64-bit with O32 or 32-bit */
	33	return (IS_ENABLED(CONFIG_32BIT) \|\|
	34	test_tsk_thread_flag(task, TIF_32BIT_REGS)) &&
	35	(regs->regs[2] == __NR_syscall);
	36	}
	37
c0ff3c53 RB	38	static inline long syscall_get_nr(struct task_struct *task,
	39	struct pt_regs *regs)
	40	{
c2d9f177	41	return current_thread_info()->syscall;
c0ff3c53 RB	42	}
c0ff3c53 RB	43
de8cd0dc JH	44	static inline void mips_syscall_update_nr(struct task_struct *task,
	45	struct pt_regs *regs)
	46	{
	47	/*
	48	* v0 is the system call number, except for O32 ABI syscall(), where it
	49	* ends up in a0.
	50	*/
	51	if (mips_syscall_is_indirect(task, regs))
	52	task_thread_info(task)->syscall = regs->regs[4];
	53	else
	54	task_thread_info(task)->syscall = regs->regs[2];
	55	}
	56
077ff3be	57	static inline void mips_get_syscall_arg(unsigned long *arg,
c0ff3c53 RB	58	struct task_struct task, struct pt_regs regs, unsigned int n)
c0ff3c53 RB	59	{
63238f2c	60	unsigned long usp __maybe_unused = regs->regs[29];
c0ff3c53 RB	61
	62	switch (n) {
	63	case 0: case 1: case 2: case 3:
	64	*arg = regs->regs[4 + n];
	65
077ff3be	66	return;
c0ff3c53 RB	67
	68	#ifdef CONFIG_32BIT
	69	case 4: case 5: case 6: case 7:
077ff3be NC	70	get_user(arg, (int )usp + n);
077ff3be NC	71	return;
c0ff3c53 RB	72	#endif
	73
	74	#ifdef CONFIG_64BIT
	75	case 4: case 5: case 6: case 7:
	76	#ifdef CONFIG_MIPS32_O32
c50cbd85	77	if (test_tsk_thread_flag(task, TIF_32BIT_REGS))
077ff3be	78	get_user(arg, (int )usp + n);
c0ff3c53 RB	79	else
	80	#endif
	81	*arg = regs->regs[4 + n];
	82
077ff3be	83	return;
c0ff3c53 RB	84	#endif
	85
	86	default:
	87	BUG();
	88	}
f5179287 RB	89
f5179287 RB	90	unreachable();
c0ff3c53 RB	91	}
c0ff3c53 RB	92
ba849160 DL	93	static inline long syscall_get_error(struct task_struct *task,
	94	struct pt_regs *regs)
	95	{
	96	return regs->regs[7] ? -regs->regs[2] : 0;
	97	}
	98
1d7bf993 RB	99	static inline long syscall_get_return_value(struct task_struct *task,
	100	struct pt_regs *regs)
	101	{
	102	return regs->regs[2];
	103	}
	104
22feadbe MC	105	static inline void syscall_rollback(struct task_struct *task,
	106	struct pt_regs *regs)
	107	{
	108	/* Do nothing */
	109	}
	110
1d7bf993 RB	111	static inline void syscall_set_return_value(struct task_struct *task,
	112	struct pt_regs *regs,
	113	int error, long val)
	114	{
	115	if (error) {
	116	regs->regs[2] = -error;
becddba9	117	regs->regs[7] = 1;
1d7bf993 RB	118	} else {
	119	regs->regs[2] = val;
	120	regs->regs[7] = 0;
	121	}
	122	}
	123
c0ff3c53 RB	124	static inline void syscall_get_arguments(struct task_struct *task,
c0ff3c53 RB	125	struct pt_regs *regs,
c0ff3c53 RB	126	unsigned long *args)
c0ff3c53 RB	127	{
b35f549d SRRH	128	unsigned int i = 0;
b35f549d SRRH	129	unsigned int n = 6;
de8cd0dc JH	130
	131	/* O32 ABI syscall() */
	132	if (mips_syscall_is_indirect(task, regs))
4c21b8fd	133	i++;
c0ff3c53 RB	134
c0ff3c53 RB	135	while (n--)
077ff3be	136	mips_get_syscall_arg(args++, task, regs, i++);
c0ff3c53 RB	137	}
c0ff3c53 RB	138
19e2e172 RB	139	extern const unsigned long sys_call_table[];
	140	extern const unsigned long sys32_call_table[];
	141	extern const unsigned long sysn32_call_table[];
	142
16add411	143	static inline int syscall_get_arch(struct task_struct *task)
bec9b2b2	144	{
ce5d1128	145	int arch = AUDIT_ARCH_MIPS;
bec9b2b2	146	#ifdef CONFIG_64BIT
16add411	147	if (!test_tsk_thread_flag(task, TIF_32BIT_REGS)) {
6e345746	148	arch \|= __AUDIT_ARCH_64BIT;
40381529	149	/* N32 sets only TIF_32BIT_ADDR */
16add411	150	if (test_tsk_thread_flag(task, TIF_32BIT_ADDR))
40381529 MC	151	arch \|= __AUDIT_ARCH_CONVENTION_MIPS64_N32;
40381529 MC	152	}
bec9b2b2 RB	153	#endif
	154	#if defined(__LITTLE_ENDIAN)
	155	arch \|= __AUDIT_ARCH_LE;
	156	#endif
	157	return arch;
	158	}
	159
19e2e172	160	#endif /* __ASM_MIPS_SYSCALL_H */