summaryrefslogtreecommitdiffstats
path: root/arch/um/kernel/syscall.c
blob: b9d92b2089aed6cb0b3a5d67d0dafce8fd0051dc (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
/*
 * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
 * Licensed under the GPL
 */

#include "linux/file.h"
#include "linux/fs.h"
#include "linux/mm.h"
#include "linux/sched.h"
#include "linux/utsname.h"
#include "asm/current.h"
#include "asm/mman.h"
#include "asm/uaccess.h"
#include "asm/unistd.h"

/*  Unlocked, I don't care if this is a bit off */
int nsyscalls = 0;

long sys_fork(void)
{
	long ret;

	current->thread.forking = 1;
	ret = do_fork(SIGCHLD, UPT_SP(&current->thread.regs.regs),
		      &current->thread.regs, 0, NULL, NULL);
	current->thread.forking = 0;
	return ret;
}

long sys_vfork(void)
{
	long ret;

	current->thread.forking = 1;
	ret = do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD,
		      UPT_SP(&current->thread.regs.regs),
		      &current->thread.regs, 0, NULL, NULL);
	current->thread.forking = 0;
	return ret;
}

/* common code for old and new mmaps */
long sys_mmap2(unsigned long addr, unsigned long len,
	       unsigned long prot, unsigned long flags,
	       unsigned long fd, unsigned long pgoff)
{
	long error = -EBADF;
	struct file * file = NULL;

	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
	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;
}

long old_mmap(unsigned long addr, unsigned long len,
	      unsigned long prot, unsigned long flags,
	      unsigned long fd, unsigned long offset)
{
	long err = -EINVAL;
	if (offset & ~PAGE_MASK)
		goto out;

	err = sys_mmap2(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
 out:
	return err;
}
/*
 * sys_pipe() is the normal C calling standard for creating
 * a pipe. It's not the way unix traditionally does this, though.
 */
long sys_pipe(unsigned long __user * fildes)
{
	int fd[2];
	long error;

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


long sys_uname(struct old_utsname __user * name)
{
	long err;
	if (!name)
		return -EFAULT;
	down_read(&uts_sem);
	err = copy_to_user(name, utsname(), sizeof (*name));
	up_read(&uts_sem);
	return err?-EFAULT:0;
}

long sys_olduname(struct oldold_utsname __user * name)
{
	long error;

	if (!name)
		return -EFAULT;
	if (!access_ok(VERIFY_WRITE,name,sizeof(struct oldold_utsname)))
		return -EFAULT;

	down_read(&uts_sem);

	error = __copy_to_user(&name->sysname, &utsname()->sysname,
			       __OLD_UTS_LEN);
	error |= __put_user(0, name->sysname + __OLD_UTS_LEN);
	error |= __copy_to_user(&name->nodename, &utsname()->nodename,
				__OLD_UTS_LEN);
	error |= __put_user(0, name->nodename + __OLD_UTS_LEN);
	error |= __copy_to_user(&name->release, &utsname()->release,
				__OLD_UTS_LEN);
	error |= __put_user(0, name->release + __OLD_UTS_LEN);
	error |= __copy_to_user(&name->version, &utsname()->version,
				__OLD_UTS_LEN);
	error |= __put_user(0, name->version + __OLD_UTS_LEN);
	error |= __copy_to_user(&name->machine, &utsname()->machine,
				__OLD_UTS_LEN);
	error |= __put_user(0, name->machine + __OLD_UTS_LEN);

	up_read(&uts_sem);

	error = error ? -EFAULT : 0;

	return error;
}

int kernel_execve(const char *filename, char *const argv[], char *const envp[])
{
	mm_segment_t fs;
	int ret;

	fs = get_fs();
	set_fs(KERNEL_DS);
	ret = um_execve(filename, argv, envp);
	set_fs(fs);

	return ret;
}