summaryrefslogtreecommitdiffstats
path: root/arch/arm/kernel/sys_arm.c
blob: ef32577da304ba7f4c13a9c92d0f6a36631d3376 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
/*
 *  linux/arch/arm/kernel/sys_arm.c
 *
 *  Copyright (C) People who wrote linux/arch/i386/kernel/sys_i386.c
 *  Copyright (C) 1995, 1996 Russell King.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 *  This file contains various random system calls that
 *  have a non-standard calling sequence on the Linux/arm
 *  platform.
 */
#include <linux/module.h>
#include <linux/errno.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/sem.h>
#include <linux/msg.h>
#include <linux/shm.h>
#include <linux/stat.h>
#include <linux/syscalls.h>
#include <linux/mman.h>
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/utsname.h>

#include <asm/uaccess.h>
#include <asm/ipc.h>

extern unsigned long do_mremap(unsigned long addr, unsigned long old_len,
			       unsigned long new_len, unsigned long flags,
			       unsigned long new_addr);

/*
 * sys_pipe() is the normal C calling standard for creating
 * a pipe. It's not the way unix traditionally does this, though.
 */
asmlinkage int sys_pipe(unsigned long __user *fildes)
{
	int fd[2];
	int error;

	error = do_pipe(fd);
	if (!error) {
		if (copy_to_user(fildes, fd, 2*sizeof(int)))
			error = -EFAULT;
	}
	return error;
}

/* common code for old and new mmaps */
inline long do_mmap2(
	unsigned long addr, unsigned long len,
	unsigned long prot, unsigned long flags,
	unsigned long fd, unsigned long pgoff)
{
	int error = -EINVAL;
	struct file * file = NULL;

	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);

	if (flags & MAP_FIXED && addr < FIRST_USER_ADDRESS)
		goto out;

	error = -EBADF;
	if (!(flags & MAP_ANONYMOUS)) {
		file = fget(fd);
		if (!file)
			goto out;
	}

	down_write(&current->mm->mmap_sem);
	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
	up_write(&current->mm->mmap_sem);

	if (file)
		fput(file);
out:
	return error;
}

struct mmap_arg_struct {
	unsigned long addr;
	unsigned long len;
	unsigned long prot;
	unsigned long flags;
	unsigned long fd;
	unsigned long offset;
};

asmlinkage int old_mmap(struct mmap_arg_struct __user *arg)
{
	int error = -EFAULT;
	struct mmap_arg_struct a;

	if (copy_from_user(&a, arg, sizeof(a)))
		goto out;

	error = -EINVAL;
	if (a.offset & ~PAGE_MASK)
		goto out;

	error = do_mmap2(a.addr, a.len, a.prot, a.flags, a.fd, a.offset >> PAGE_SHIFT);
out:
	return error;
}

asmlinkage unsigned long
sys_arm_mremap(unsigned long addr, unsigned long old_len,
	       unsigned long new_len, unsigned long flags,
	       unsigned long new_addr)
{
	unsigned long ret = -EINVAL;

	if (flags & MREMAP_FIXED && new_addr < FIRST_USER_ADDRESS)
		goto out;

	down_write(&current->mm->mmap_sem);
	ret = do_mremap(addr, old_len, new_len, flags, new_addr);
	up_write(&current->mm->mmap_sem);

out:
	return ret;
}

/*
 * Perform the select(nd, in, out, ex, tv) and mmap() system
 * calls.
 */

struct sel_arg_struct {
	unsigned long n;
	fd_set __user *inp, *outp, *exp;
	struct timeval __user *tvp;
};

asmlinkage int old_select(struct sel_arg_struct __user *arg)
{
	struct sel_arg_struct a;

	if (copy_from_user(&a, arg, sizeof(a)))
		return -EFAULT;
	/* sys_select() does the appropriate kernel locking */
	return sys_select(a.n, a.inp, a.outp, a.exp, a.tvp);
}

/*
 * sys_ipc() is the de-multiplexer for the SysV IPC calls..
 *
 * This is really horribly ugly.
 */
asmlinkage int sys_ipc(uint call, int first, int second, int third,
		       void __user *ptr, long fifth)
{
	int version, ret;

	version = call >> 16; /* hack for backward compatibility */
	call &= 0xffff;

	switch (call) {
	case SEMOP:
		return sys_semtimedop (first, (struct sembuf __user *)ptr, second, NULL);
	case SEMTIMEDOP:
		return sys_semtimedop(first, (struct sembuf __user *)ptr, second,
					(const struct timespec __user *)fifth);

	case SEMGET:
		return sys_semget (first, second, third);
	case SEMCTL: {
		union semun fourth;
		if (!ptr)
			return -EINVAL;
		if (get_user(fourth.__pad, (void __user * __user *) ptr))
			return -EFAULT;
		return sys_semctl (first, second, third, fourth);
	}

	case MSGSND:
		return sys_msgsnd(first, (struct msgbuf __user *) ptr, 
				  second, third);
	case MSGRCV:
		switch (version) {
		case 0: {
			struct ipc_kludge tmp;
			if (!ptr)
				return -EINVAL;
			if (copy_from_user(&tmp,(struct ipc_kludge __user *)ptr,
					   sizeof (tmp)))
				return -EFAULT;
			return sys_msgrcv (first, tmp.msgp, second,
					   tmp.msgtyp, third);
		}
		default:
			return sys_msgrcv (first,
					   (struct msgbuf __user *) ptr,
					   second, fifth, third);
		}
	case MSGGET:
		return sys_msgget ((key_t) first, second);
	case MSGCTL:
		return sys_msgctl(first, second, (struct msqid_ds __user *)ptr);

	case SHMAT:
		switch (version) {
		default: {
			ulong raddr;
			ret = do_shmat(first, (char __user *)ptr, second, &raddr);
			if (ret)
				return ret;
			return put_user(raddr, (ulong __user *)third);
		}
		case 1: /* Of course, we don't support iBCS2! */
			return -EINVAL;
		}
	case SHMDT: 
		return sys_shmdt ((char __user *)ptr);
	case SHMGET:
		return sys_shmget (first, second, third);
	case SHMCTL:
		return sys_shmctl (first, second,
				   (struct shmid_ds __user *) ptr);
	default:
		return -ENOSYS;
	}
}

/* Fork a new task - this creates a new program thread.
 * This is called indirectly via a small wrapper
 */
asmlinkage int sys_fork(struct pt_regs *regs)
{
	return do_fork(SIGCHLD, regs->ARM_sp, regs, 0, NULL, NULL);
}

/* Clone a task - this clones the calling program thread.
 * This is called indirectly via a small wrapper
 */
asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
			 int __user *parent_tidptr, int tls_val,
			 int __user *child_tidptr, struct pt_regs *regs)
{
	if (!newsp)
		newsp = regs->ARM_sp;

	return do_fork(clone_flags, newsp, regs, 0, parent_tidptr, child_tidptr);
}

asmlinkage int sys_vfork(struct pt_regs *regs)
{
	return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->ARM_sp, regs, 0, NULL, NULL);
}

/* sys_execve() executes a new program.
 * This is called indirectly via a small wrapper
 */
asmlinkage int sys_execve(char __user *filenamei, char __user * __user *argv,
			  char __user * __user *envp, struct pt_regs *regs)
{
	int error;
	char * filename;

	filename = getname(filenamei);
	error = PTR_ERR(filename);
	if (IS_ERR(filename))
		goto out;
	error = do_execve(filename, argv, envp, regs);
	putname(filename);
out:
	return error;
}

long execve(const char *filename, char **argv, char **envp)
{
	struct pt_regs regs;
	int ret;

	memset(&regs, 0, sizeof(struct pt_regs));
	ret = do_execve((char *)filename, (char __user * __user *)argv,
			(char __user * __user *)envp, &regs);
	if (ret < 0)
		goto out;

	/*
	 * Save argc to the register structure for userspace.
	 */
	regs.ARM_r0 = ret;

	/*
	 * We were successful.  We won't be returning to our caller, but
	 * instead to user space by manipulating the kernel stack.
	 */
	asm(	"add	r0, %0, %1\n\t"
		"mov	r1, %2\n\t"
		"mov	r2, %3\n\t"
		"bl	memmove\n\t"	/* copy regs to top of stack */
		"mov	r8, #0\n\t"	/* not a syscall */
		"mov	r9, %0\n\t"	/* thread structure */
		"mov	sp, r0\n\t"	/* reposition stack pointer */
		"b	ret_to_user"
		:
		: "r" (current_thread_info()),
		  "Ir" (THREAD_SIZE - 8 - sizeof(regs)),
		  "r" (&regs),
		  "Ir" (sizeof(regs))
		: "r0", "r1", "r2", "r3", "ip", "memory");

 out:
	return ret;
}
EXPORT_SYMBOL(execve);