[GitHub/mt8127/android_kernel_alcatel_ttab.git] / arch / mips / kernel / syscall.c

/*
 * 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, 1996, 1997, 2000, 2001, 05 by Ralf Baechle
 * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
 * Copyright (C) 2001 MIPS Technologies, Inc.
 */
#include <linux/capability.h>
#include <linux/errno.h>
#include <linux/linkage.h>
#include <linux/fs.h>
#include <linux/smp.h>
#include <linux/ptrace.h>
#include <linux/string.h>
#include <linux/syscalls.h>
#include <linux/file.h>
#include <linux/utsname.h>
#include <linux/unistd.h>
#include <linux/sem.h>
#include <linux/msg.h>
#include <linux/shm.h>
#include <linux/compiler.h>
#include <linux/ipc.h>
#include <linux/uaccess.h>
#include <linux/slab.h>
#include <linux/elf.h>

#include <asm/asm.h>
#include <asm/branch.h>
#include <asm/cachectl.h>
#include <asm/cacheflush.h>
#include <asm/asm-offsets.h>
#include <asm/signal.h>
#include <asm/sim.h>
#include <asm/shmparam.h>
#include <asm/sysmips.h>
#include <asm/uaccess.h>
#include <asm/switch_to.h>

/*
 * For historic reasons the pipe(2) syscall on MIPS has an unusual calling
 * convention.  It returns results in registers $v0 / $v1 which means there
 * is no need for it to do verify the validity of a userspace pointer
 * argument.  Historically that used to be expensive in Linux.  These days
 * the performance advantage is negligible.
 */
asmlinkage int sysm_pipe(nabi_no_regargs volatile struct pt_regs regs)
{
	int fd[2];
	int error, res;

	error = do_pipe_flags(fd, 0);
	if (error) {
		res = error;
		goto out;
	}
	regs.regs[3] = fd[1];
	res = fd[0];
out:
	return res;
}

SYSCALL_DEFINE6(mips_mmap, unsigned long, addr, unsigned long, len,
	unsigned long, prot, unsigned long, flags, unsigned long,
	fd, off_t, offset)
{
	unsigned long result;

	result = -EINVAL;
	if (offset & ~PAGE_MASK)
		goto out;

	result = sys_mmap_pgoff(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);

out:
	return result;
}

SYSCALL_DEFINE6(mips_mmap2, unsigned long, addr, unsigned long, len,
	unsigned long, prot, unsigned long, flags, unsigned long, fd,
	unsigned long, pgoff)
{
	if (pgoff & (~PAGE_MASK >> 12))
		return -EINVAL;

	return sys_mmap_pgoff(addr, len, prot, flags, fd, pgoff >> (PAGE_SHIFT-12));
}

save_static_function(sys_fork);
static int __used noinline
_sys_fork(nabi_no_regargs struct pt_regs regs)
{
	return do_fork(SIGCHLD, regs.regs[29], 0, NULL, NULL);
}

save_static_function(sys_clone);
static int __used noinline
_sys_clone(nabi_no_regargs struct pt_regs regs)
{
	unsigned long clone_flags;
	unsigned long newsp;
	int __user *parent_tidptr, *child_tidptr;

	clone_flags = regs.regs[4];
	newsp = regs.regs[5];
	if (!newsp)
		newsp = regs.regs[29];
	parent_tidptr = (int __user *) regs.regs[6];
#ifdef CONFIG_32BIT
	/* We need to fetch the fifth argument off the stack.  */
	child_tidptr = NULL;
	if (clone_flags & (CLONE_CHILD_SETTID | CLONE_CHILD_CLEARTID)) {
		int __user *__user *usp = (int __user *__user *) regs.regs[29];
		if (regs.regs[2] == __NR_syscall) {
			if (get_user (child_tidptr, &usp[5]))
				return -EFAULT;
		}
		else if (get_user (child_tidptr, &usp[4]))
			return -EFAULT;
	}
#else
	child_tidptr = (int __user *) regs.regs[8];
#endif
	return do_fork(clone_flags, newsp, 0,
	               parent_tidptr, child_tidptr);
}

SYSCALL_DEFINE1(set_thread_area, unsigned long, addr)
{
	struct thread_info *ti = task_thread_info(current);

	ti->tp_value = addr;
	if (cpu_has_userlocal)
		write_c0_userlocal(addr);

	return 0;
}

static inline int mips_atomic_set(struct pt_regs *regs,
	unsigned long addr, unsigned long new)
{
	unsigned long old, tmp;
	unsigned int err;

	if (unlikely(addr & 3))
		return -EINVAL;

	if (unlikely(!access_ok(VERIFY_WRITE, addr, 4)))
		return -EINVAL;

	if (cpu_has_llsc && R10000_LLSC_WAR) {
		__asm__ __volatile__ (
		"	.set	mips3					\n"
		"	li	%[err], 0				\n"
		"1:	ll	%[old], (%[addr])			\n"
		"	move	%[tmp], %[new]				\n"
		"2:	sc	%[tmp], (%[addr])			\n"
		"	beqzl	%[tmp], 1b				\n"
		"3:							\n"
		"	.section .fixup,\"ax\"				\n"
		"4:	li	%[err], %[efault]			\n"
		"	j	3b					\n"
		"	.previous					\n"
		"	.section __ex_table,\"a\"			\n"
		"	"STR(PTR)"	1b, 4b				\n"
		"	"STR(PTR)"	2b, 4b				\n"
		"	.previous					\n"
		"	.set	mips0					\n"
		: [old] "=&r" (old),
		  [err] "=&r" (err),
		  [tmp] "=&r" (tmp)
		: [addr] "r" (addr),
		  [new] "r" (new),
		  [efault] "i" (-EFAULT)
		: "memory");
	} else if (cpu_has_llsc) {
		__asm__ __volatile__ (
		"	.set	mips3					\n"
		"	li	%[err], 0				\n"
		"1:	ll	%[old], (%[addr])			\n"
		"	move	%[tmp], %[new]				\n"
		"2:	sc	%[tmp], (%[addr])			\n"
		"	bnez	%[tmp], 4f				\n"
		"3:							\n"
		"	.subsection 2					\n"
		"4:	b	1b					\n"
		"	.previous					\n"
		"							\n"
		"	.section .fixup,\"ax\"				\n"
		"5:	li	%[err], %[efault]			\n"
		"	j	3b					\n"
		"	.previous					\n"
		"	.section __ex_table,\"a\"			\n"
		"	"STR(PTR)"	1b, 5b				\n"
		"	"STR(PTR)"	2b, 5b				\n"
		"	.previous					\n"
		"	.set	mips0					\n"
		: [old] "=&r" (old),
		  [err] "=&r" (err),
		  [tmp] "=&r" (tmp)
		: [addr] "r" (addr),
		  [new] "r" (new),
		  [efault] "i" (-EFAULT)
		: "memory");
	} else {
		do {
			preempt_disable();
			ll_bit = 1;
			ll_task = current;
			preempt_enable();

			err = __get_user(old, (unsigned int *) addr);
			err |= __put_user(new, (unsigned int *) addr);
			if (err)
				break;
			rmb();
		} while (!ll_bit);
	}

	if (unlikely(err))
		return err;

	regs->regs[2] = old;
	regs->regs[7] = 0;	/* No error */

	/*
	 * Don't let your children do this ...
	 */
	__asm__ __volatile__(
	"	move	$29, %0						\n"
	"	j	syscall_exit					\n"
	: /* no outputs */
	: "r" (regs));

	/* unreached.  Honestly.  */
	unreachable();
}

save_static_function(sys_sysmips);
static int __used noinline
_sys_sysmips(nabi_no_regargs struct pt_regs regs)
{
	long cmd, arg1, arg2;

	cmd = regs.regs[4];
	arg1 = regs.regs[5];
	arg2 = regs.regs[6];

	switch (cmd) {
	case MIPS_ATOMIC_SET:
		return mips_atomic_set(&regs, arg1, arg2);

	case MIPS_FIXADE:
		if (arg1 & ~3)
			return -EINVAL;

		if (arg1 & 1)
			set_thread_flag(TIF_FIXADE);
		else
			clear_thread_flag(TIF_FIXADE);
		if (arg1 & 2)
			set_thread_flag(TIF_LOGADE);
		else
			clear_thread_flag(TIF_LOGADE);

		return 0;

	case FLUSH_CACHE:
		__flush_cache_all();
		return 0;
	}

	return -EINVAL;
}

/*
 * No implemented yet ...
 */
SYSCALL_DEFINE3(cachectl, char *, addr, int, nbytes, int, op)
{
	return -ENOSYS;
}

/*
 * If we ever come here the user sp is bad.  Zap the process right away.
 * Due to the bad stack signaling wouldn't work.
 */
asmlinkage void bad_stack(void)
{
	do_exit(SIGSEGV);
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* This file is subject to the terms and conditions of the GNU General Public
	3	* License. See the file "COPYING" in the main directory of this archive
	4	* for more details.
	5	*
	6	* Copyright (C) 1995, 1996, 1997, 2000, 2001, 05 by Ralf Baechle
	7	* Copyright (C) 1999, 2000 Silicon Graphics, Inc.
	8	* Copyright (C) 2001 MIPS Technologies, Inc.
	9	*/
a9415644	10	#include <linux/capability.h>
1da177e4 LT	11	#include <linux/errno.h>
1da177e4 LT	12	#include <linux/linkage.h>
4e950f6f	13	#include <linux/fs.h>
1da177e4	14	#include <linux/smp.h>
1da177e4	15	#include <linux/ptrace.h>
1da177e4 LT	16	#include <linux/string.h>
	17	#include <linux/syscalls.h>
	18	#include <linux/file.h>
1da177e4 LT	19	#include <linux/utsname.h>
	20	#include <linux/unistd.h>
	21	#include <linux/sem.h>
	22	#include <linux/msg.h>
	23	#include <linux/shm.h>
	24	#include <linux/compiler.h>
cba4fbbf	25	#include <linux/ipc.h>
f1e39a4a	26	#include <linux/uaccess.h>
5a0e3ad6	27	#include <linux/slab.h>
652b14aa	28	#include <linux/elf.h>
1da177e4	29
f1e39a4a	30	#include <asm/asm.h>
1da177e4 LT	31	#include <asm/branch.h>
	32	#include <asm/cachectl.h>
	33	#include <asm/cacheflush.h>
048eb582	34	#include <asm/asm-offsets.h>
1da177e4 LT	35	#include <asm/signal.h>
	36	#include <asm/sim.h>
	37	#include <asm/shmparam.h>
	38	#include <asm/sysmips.h>
	39	#include <asm/uaccess.h>
b81947c6	40	#include <asm/switch_to.h>
1da177e4	41
8213bbf9 RB	42	/*
	43	* For historic reasons the pipe(2) syscall on MIPS has an unusual calling
	44	* convention. It returns results in registers $v0 / $v1 which means there
	45	* is no need for it to do verify the validity of a userspace pointer
	46	* argument. Historically that used to be expensive in Linux. These days
	47	* the performance advantage is negligible.
	48	*/
	49	asmlinkage int sysm_pipe(nabi_no_regargs volatile struct pt_regs regs)
1da177e4 LT	50	{
	51	int fd[2];
	52	int error, res;
	53
ed8cae8b	54	error = do_pipe_flags(fd, 0);
1da177e4 LT	55	if (error) {
	56	res = error;
	57	goto out;
	58	}
	59	regs.regs[3] = fd[1];
	60	res = fd[0];
	61	out:
	62	return res;
	63	}
	64
dbda6ac0 RB	65	SYSCALL_DEFINE6(mips_mmap, unsigned long, addr, unsigned long, len,
	66	unsigned long, prot, unsigned long, flags, unsigned long,
	67	fd, off_t, offset)
1da177e4 LT	68	{
	69	unsigned long result;
	70
	71	result = -EINVAL;
	72	if (offset & ~PAGE_MASK)
	73	goto out;
	74
f8b72560	75	result = sys_mmap_pgoff(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
1da177e4 LT	76
	77	out:
	78	return result;
	79	}
	80
dbda6ac0 RB	81	SYSCALL_DEFINE6(mips_mmap2, unsigned long, addr, unsigned long, len,
	82	unsigned long, prot, unsigned long, flags, unsigned long, fd,
	83	unsigned long, pgoff)
1da177e4	84	{
947df17c PA	85	if (pgoff & (~PAGE_MASK >> 12))
	86	return -EINVAL;
	87
f8b72560	88	return sys_mmap_pgoff(addr, len, prot, flags, fd, pgoff >> (PAGE_SHIFT-12));
1da177e4 LT	89	}
	90
	91	save_static_function(sys_fork);
f5dbeaf5	92	static int __used noinline
1da177e4 LT	93	_sys_fork(nabi_no_regargs struct pt_regs regs)
1da177e4 LT	94	{
e80d6661	95	return do_fork(SIGCHLD, regs.regs[29], 0, NULL, NULL);
1da177e4 LT	96	}
	97
	98	save_static_function(sys_clone);
f5dbeaf5	99	static int __used noinline
1da177e4 LT	100	_sys_clone(nabi_no_regargs struct pt_regs regs)
	101	{
	102	unsigned long clone_flags;
	103	unsigned long newsp;
3c37026d	104	int __user parent_tidptr, child_tidptr;
1da177e4 LT	105
	106	clone_flags = regs.regs[4];
	107	newsp = regs.regs[5];
	108	if (!newsp)
	109	newsp = regs.regs[29];
3c37026d RB	110	parent_tidptr = (int __user *) regs.regs[6];
	111	#ifdef CONFIG_32BIT
	112	/* We need to fetch the fifth argument off the stack. */
	113	child_tidptr = NULL;
	114	if (clone_flags & (CLONE_CHILD_SETTID \| CLONE_CHILD_CLEARTID)) {
	115	int __user __user usp = (int __user __user ) regs.regs[29];
	116	if (regs.regs[2] == __NR_syscall) {
	117	if (get_user (child_tidptr, &usp[5]))
	118	return -EFAULT;
	119	}
	120	else if (get_user (child_tidptr, &usp[4]))
	121	return -EFAULT;
	122	}
	123	#else
	124	child_tidptr = (int __user *) regs.regs[8];
	125	#endif
e80d6661	126	return do_fork(clone_flags, newsp, 0,
1da177e4 LT	127	parent_tidptr, child_tidptr);
	128	}
	129
dbda6ac0	130	SYSCALL_DEFINE1(set_thread_area, unsigned long, addr)
3c37026d	131	{
dc8f6029	132	struct thread_info *ti = task_thread_info(current);
3c37026d RB	133
3c37026d RB	134	ti->tp_value = addr;
a3692020 RB	135	if (cpu_has_userlocal)
a3692020 RB	136	write_c0_userlocal(addr);
06be375b RB	137
06be375b RB	138	return 0;
3c37026d RB	139	}
3c37026d RB	140
f1e39a4a RB	141	static inline int mips_atomic_set(struct pt_regs *regs,
f1e39a4a RB	142	unsigned long addr, unsigned long new)
1da177e4	143	{
f1e39a4a RB	144	unsigned long old, tmp;
	145	unsigned int err;
	146
	147	if (unlikely(addr & 3))
	148	return -EINVAL;
	149
	150	if (unlikely(!access_ok(VERIFY_WRITE, addr, 4)))
	151	return -EINVAL;
	152
	153	if (cpu_has_llsc && R10000_LLSC_WAR) {
	154	__asm__ __volatile__ (
a91be9ee	155	" .set mips3 \n"
f1e39a4a RB	156	" li %[err], 0 \n"
	157	"1: ll %[old], (%[addr]) \n"
	158	" move %[tmp], %[new] \n"
	159	"2: sc %[tmp], (%[addr]) \n"
	160	" beqzl %[tmp], 1b \n"
	161	"3: \n"
	162	" .section .fixup,\"ax\" \n"
	163	"4: li %[err], %[efault] \n"
	164	" j 3b \n"
	165	" .previous \n"
	166	" .section __ex_table,\"a\" \n"
	167	" "STR(PTR)" 1b, 4b \n"
	168	" "STR(PTR)" 2b, 4b \n"
	169	" .previous \n"
a91be9ee	170	" .set mips0 \n"
f1e39a4a RB	171	: [old] "=&r" (old),
	172	[err] "=&r" (err),
	173	[tmp] "=&r" (tmp)
	174	: [addr] "r" (addr),
	175	[new] "r" (new),
	176	[efault] "i" (-EFAULT)
	177	: "memory");
	178	} else if (cpu_has_llsc) {
	179	__asm__ __volatile__ (
a91be9ee	180	" .set mips3 \n"
f1e39a4a RB	181	" li %[err], 0 \n"
	182	"1: ll %[old], (%[addr]) \n"
	183	" move %[tmp], %[new] \n"
	184	"2: sc %[tmp], (%[addr]) \n"
	185	" bnez %[tmp], 4f \n"
	186	"3: \n"
	187	" .subsection 2 \n"
	188	"4: b 1b \n"
	189	" .previous \n"
	190	" \n"
	191	" .section .fixup,\"ax\" \n"
	192	"5: li %[err], %[efault] \n"
	193	" j 3b \n"
	194	" .previous \n"
	195	" .section __ex_table,\"a\" \n"
	196	" "STR(PTR)" 1b, 5b \n"
	197	" "STR(PTR)" 2b, 5b \n"
	198	" .previous \n"
a91be9ee	199	" .set mips0 \n"
f1e39a4a RB	200	: [old] "=&r" (old),
	201	[err] "=&r" (err),
	202	[tmp] "=&r" (tmp)
	203	: [addr] "r" (addr),
	204	[new] "r" (new),
	205	[efault] "i" (-EFAULT)
	206	: "memory");
	207	} else {
	208	do {
	209	preempt_disable();
	210	ll_bit = 1;
	211	ll_task = current;
	212	preempt_enable();
	213
	214	err = __get_user(old, (unsigned int *) addr);
	215	err \|= __put_user(new, (unsigned int *) addr);
	216	if (err)
	217	break;
	218	rmb();
	219	} while (!ll_bit);
	220	}
	221
	222	if (unlikely(err))
	223	return err;
	224
	225	regs->regs[2] = old;
	226	regs->regs[7] = 0; /* No error */
	227
	228	/*
	229	* Don't let your children do this ...
	230	*/
	231	__asm__ __volatile__(
	232	" move $29, %0 \n"
	233	" j syscall_exit \n"
	234	: /* no outputs */
	235	: "r" (regs));
	236
	237	/* unreached. Honestly. */
f2ace931	238	unreachable();
f1e39a4a RB	239	}
	240
	241	save_static_function(sys_sysmips);
	242	static int __used noinline
	243	_sys_sysmips(nabi_no_regargs struct pt_regs regs)
	244	{
7a6e4ca1	245	long cmd, arg1, arg2;
f1e39a4a RB	246
	247	cmd = regs.regs[4];
	248	arg1 = regs.regs[5];
	249	arg2 = regs.regs[6];
f1e39a4a	250
293c5bd1	251	switch (cmd) {
1da177e4	252	case MIPS_ATOMIC_SET:
f1e39a4a	253	return mips_atomic_set(&regs, arg1, arg2);
1da177e4 LT	254
1da177e4 LT	255	case MIPS_FIXADE:
293c5bd1 RB	256	if (arg1 & ~3)
	257	return -EINVAL;
	258
	259	if (arg1 & 1)
	260	set_thread_flag(TIF_FIXADE);
	261	else
	262	clear_thread_flag(TIF_FIXADE);
	263	if (arg1 & 2)
	264	set_thread_flag(TIF_LOGADE);
	265	else
e56293b1	266	clear_thread_flag(TIF_LOGADE);
293c5bd1	267
1da177e4 LT	268	return 0;
	269
	270	case FLUSH_CACHE:
	271	__flush_cache_all();
	272	return 0;
1da177e4 LT	273	}
	274
	275	return -EINVAL;
	276	}
	277
1da177e4 LT	278	/*
	279	* No implemented yet ...
	280	*/
dbda6ac0	281	SYSCALL_DEFINE3(cachectl, char *, addr, int, nbytes, int, op)
1da177e4 LT	282	{
	283	return -ENOSYS;
	284	}
	285
	286	/*
	287	* If we ever come here the user sp is bad. Zap the process right away.
	288	* Due to the bad stack signaling wouldn't work.
	289	*/
	290	asmlinkage void bad_stack(void)
	291	{
	292	do_exit(SIGSEGV);
	293	}