xref: /openbmc/linux/arch/arm/kernel/sys_arm.c (revision a09d2831)
1 /*
2  *  linux/arch/arm/kernel/sys_arm.c
3  *
4  *  Copyright (C) People who wrote linux/arch/i386/kernel/sys_i386.c
5  *  Copyright (C) 1995, 1996 Russell King.
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  *
11  *  This file contains various random system calls that
12  *  have a non-standard calling sequence on the Linux/arm
13  *  platform.
14  */
15 #include <linux/module.h>
16 #include <linux/errno.h>
17 #include <linux/sched.h>
18 #include <linux/slab.h>
19 #include <linux/mm.h>
20 #include <linux/sem.h>
21 #include <linux/msg.h>
22 #include <linux/shm.h>
23 #include <linux/stat.h>
24 #include <linux/syscalls.h>
25 #include <linux/mman.h>
26 #include <linux/fs.h>
27 #include <linux/file.h>
28 #include <linux/ipc.h>
29 #include <linux/uaccess.h>
30 
31 struct mmap_arg_struct {
32 	unsigned long addr;
33 	unsigned long len;
34 	unsigned long prot;
35 	unsigned long flags;
36 	unsigned long fd;
37 	unsigned long offset;
38 };
39 
40 asmlinkage int old_mmap(struct mmap_arg_struct __user *arg)
41 {
42 	int error = -EFAULT;
43 	struct mmap_arg_struct a;
44 
45 	if (copy_from_user(&a, arg, sizeof(a)))
46 		goto out;
47 
48 	error = -EINVAL;
49 	if (a.offset & ~PAGE_MASK)
50 		goto out;
51 
52 	error = sys_mmap_pgoff(a.addr, a.len, a.prot, a.flags, a.fd, a.offset >> PAGE_SHIFT);
53 out:
54 	return error;
55 }
56 
57 /*
58  * Perform the select(nd, in, out, ex, tv) and mmap() system
59  * calls.
60  */
61 
62 struct sel_arg_struct {
63 	unsigned long n;
64 	fd_set __user *inp, *outp, *exp;
65 	struct timeval __user *tvp;
66 };
67 
68 asmlinkage int old_select(struct sel_arg_struct __user *arg)
69 {
70 	struct sel_arg_struct a;
71 
72 	if (copy_from_user(&a, arg, sizeof(a)))
73 		return -EFAULT;
74 	/* sys_select() does the appropriate kernel locking */
75 	return sys_select(a.n, a.inp, a.outp, a.exp, a.tvp);
76 }
77 
78 #if !defined(CONFIG_AEABI) || defined(CONFIG_OABI_COMPAT)
79 /*
80  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
81  *
82  * This is really horribly ugly.
83  */
84 asmlinkage int sys_ipc(uint call, int first, int second, int third,
85 		       void __user *ptr, long fifth)
86 {
87 	int version, ret;
88 
89 	version = call >> 16; /* hack for backward compatibility */
90 	call &= 0xffff;
91 
92 	switch (call) {
93 	case SEMOP:
94 		return sys_semtimedop (first, (struct sembuf __user *)ptr, second, NULL);
95 	case SEMTIMEDOP:
96 		return sys_semtimedop(first, (struct sembuf __user *)ptr, second,
97 					(const struct timespec __user *)fifth);
98 
99 	case SEMGET:
100 		return sys_semget (first, second, third);
101 	case SEMCTL: {
102 		union semun fourth;
103 		if (!ptr)
104 			return -EINVAL;
105 		if (get_user(fourth.__pad, (void __user * __user *) ptr))
106 			return -EFAULT;
107 		return sys_semctl (first, second, third, fourth);
108 	}
109 
110 	case MSGSND:
111 		return sys_msgsnd(first, (struct msgbuf __user *) ptr,
112 				  second, third);
113 	case MSGRCV:
114 		switch (version) {
115 		case 0: {
116 			struct ipc_kludge tmp;
117 			if (!ptr)
118 				return -EINVAL;
119 			if (copy_from_user(&tmp,(struct ipc_kludge __user *)ptr,
120 					   sizeof (tmp)))
121 				return -EFAULT;
122 			return sys_msgrcv (first, tmp.msgp, second,
123 					   tmp.msgtyp, third);
124 		}
125 		default:
126 			return sys_msgrcv (first,
127 					   (struct msgbuf __user *) ptr,
128 					   second, fifth, third);
129 		}
130 	case MSGGET:
131 		return sys_msgget ((key_t) first, second);
132 	case MSGCTL:
133 		return sys_msgctl(first, second, (struct msqid_ds __user *)ptr);
134 
135 	case SHMAT:
136 		switch (version) {
137 		default: {
138 			ulong raddr;
139 			ret = do_shmat(first, (char __user *)ptr, second, &raddr);
140 			if (ret)
141 				return ret;
142 			return put_user(raddr, (ulong __user *)third);
143 		}
144 		case 1: /* Of course, we don't support iBCS2! */
145 			return -EINVAL;
146 		}
147 	case SHMDT:
148 		return sys_shmdt ((char __user *)ptr);
149 	case SHMGET:
150 		return sys_shmget (first, second, third);
151 	case SHMCTL:
152 		return sys_shmctl (first, second,
153 				   (struct shmid_ds __user *) ptr);
154 	default:
155 		return -ENOSYS;
156 	}
157 }
158 #endif
159 
160 /* Fork a new task - this creates a new program thread.
161  * This is called indirectly via a small wrapper
162  */
163 asmlinkage int sys_fork(struct pt_regs *regs)
164 {
165 #ifdef CONFIG_MMU
166 	return do_fork(SIGCHLD, regs->ARM_sp, regs, 0, NULL, NULL);
167 #else
168 	/* can not support in nommu mode */
169 	return(-EINVAL);
170 #endif
171 }
172 
173 /* Clone a task - this clones the calling program thread.
174  * This is called indirectly via a small wrapper
175  */
176 asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp,
177 			 int __user *parent_tidptr, int tls_val,
178 			 int __user *child_tidptr, struct pt_regs *regs)
179 {
180 	if (!newsp)
181 		newsp = regs->ARM_sp;
182 
183 	return do_fork(clone_flags, newsp, regs, 0, parent_tidptr, child_tidptr);
184 }
185 
186 asmlinkage int sys_vfork(struct pt_regs *regs)
187 {
188 	return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->ARM_sp, regs, 0, NULL, NULL);
189 }
190 
191 /* sys_execve() executes a new program.
192  * This is called indirectly via a small wrapper
193  */
194 asmlinkage int sys_execve(char __user *filenamei, char __user * __user *argv,
195 			  char __user * __user *envp, struct pt_regs *regs)
196 {
197 	int error;
198 	char * filename;
199 
200 	filename = getname(filenamei);
201 	error = PTR_ERR(filename);
202 	if (IS_ERR(filename))
203 		goto out;
204 	error = do_execve(filename, argv, envp, regs);
205 	putname(filename);
206 out:
207 	return error;
208 }
209 
210 int kernel_execve(const char *filename, char *const argv[], char *const envp[])
211 {
212 	struct pt_regs regs;
213 	int ret;
214 
215 	memset(&regs, 0, sizeof(struct pt_regs));
216 	ret = do_execve((char *)filename, (char __user * __user *)argv,
217 			(char __user * __user *)envp, &regs);
218 	if (ret < 0)
219 		goto out;
220 
221 	/*
222 	 * Save argc to the register structure for userspace.
223 	 */
224 	regs.ARM_r0 = ret;
225 
226 	/*
227 	 * We were successful.  We won't be returning to our caller, but
228 	 * instead to user space by manipulating the kernel stack.
229 	 */
230 	asm(	"add	r0, %0, %1\n\t"
231 		"mov	r1, %2\n\t"
232 		"mov	r2, %3\n\t"
233 		"bl	memmove\n\t"	/* copy regs to top of stack */
234 		"mov	r8, #0\n\t"	/* not a syscall */
235 		"mov	r9, %0\n\t"	/* thread structure */
236 		"mov	sp, r0\n\t"	/* reposition stack pointer */
237 		"b	ret_to_user"
238 		:
239 		: "r" (current_thread_info()),
240 		  "Ir" (THREAD_START_SP - sizeof(regs)),
241 		  "r" (&regs),
242 		  "Ir" (sizeof(regs))
243 		: "r0", "r1", "r2", "r3", "ip", "lr", "memory");
244 
245  out:
246 	return ret;
247 }
248 EXPORT_SYMBOL(kernel_execve);
249 
250 /*
251  * Since loff_t is a 64 bit type we avoid a lot of ABI hassle
252  * with a different argument ordering.
253  */
254 asmlinkage long sys_arm_fadvise64_64(int fd, int advice,
255 				     loff_t offset, loff_t len)
256 {
257 	return sys_fadvise64_64(fd, offset, len, advice);
258 }
259