xref: /linux/arch/powerpc/kernel/syscalls.c (revision 944d79559d154c12becde0dab327016cf438f46c)
1 /*
2  *  Implementation of various system calls for Linux/PowerPC
3  *
4  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
5  *
6  * Derived from "arch/i386/kernel/sys_i386.c"
7  * Adapted from the i386 version by Gary Thomas
8  * Modified by Cort Dougan (cort@cs.nmt.edu)
9  * and Paul Mackerras (paulus@cs.anu.edu.au).
10  *
11  * This file contains various random system calls that
12  * have a non-standard calling sequence on the Linux/PPC
13  * platform.
14  *
15  *  This program is free software; you can redistribute it and/or
16  *  modify it under the terms of the GNU General Public License
17  *  as published by the Free Software Foundation; either version
18  *  2 of the License, or (at your option) any later version.
19  *
20  */
21 
22 #include <linux/errno.h>
23 #include <linux/sched.h>
24 #include <linux/syscalls.h>
25 #include <linux/mm.h>
26 #include <linux/smp.h>
27 #include <linux/smp_lock.h>
28 #include <linux/sem.h>
29 #include <linux/msg.h>
30 #include <linux/shm.h>
31 #include <linux/stat.h>
32 #include <linux/mman.h>
33 #include <linux/sys.h>
34 #include <linux/ipc.h>
35 #include <linux/utsname.h>
36 #include <linux/file.h>
37 #include <linux/init.h>
38 #include <linux/personality.h>
39 
40 #include <asm/uaccess.h>
41 #include <asm/ipc.h>
42 #include <asm/semaphore.h>
43 #include <asm/time.h>
44 #include <asm/unistd.h>
45 
46 /*
47  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
48  *
49  * This is really horribly ugly.
50  */
51 int sys_ipc(uint call, int first, unsigned long second, long third,
52 	    void __user *ptr, long fifth)
53 {
54 	int version, ret;
55 
56 	version = call >> 16; /* hack for backward compatibility */
57 	call &= 0xffff;
58 
59 	ret = -ENOSYS;
60 	switch (call) {
61 	case SEMOP:
62 		ret = sys_semtimedop(first, (struct sembuf __user *)ptr,
63 				      (unsigned)second, NULL);
64 		break;
65 	case SEMTIMEDOP:
66 		ret = sys_semtimedop(first, (struct sembuf __user *)ptr,
67 				      (unsigned)second,
68 				      (const struct timespec __user *) fifth);
69 		break;
70 	case SEMGET:
71 		ret = sys_semget (first, (int)second, third);
72 		break;
73 	case SEMCTL: {
74 		union semun fourth;
75 
76 		ret = -EINVAL;
77 		if (!ptr)
78 			break;
79 		if ((ret = get_user(fourth.__pad, (void __user * __user *)ptr)))
80 			break;
81 		ret = sys_semctl(first, (int)second, third, fourth);
82 		break;
83 	}
84 	case MSGSND:
85 		ret = sys_msgsnd(first, (struct msgbuf __user *)ptr,
86 				 (size_t)second, third);
87 		break;
88 	case MSGRCV:
89 		switch (version) {
90 		case 0: {
91 			struct ipc_kludge tmp;
92 
93 			ret = -EINVAL;
94 			if (!ptr)
95 				break;
96 			if ((ret = copy_from_user(&tmp,
97 						(struct ipc_kludge __user *) ptr,
98 						sizeof (tmp)) ? -EFAULT : 0))
99 				break;
100 			ret = sys_msgrcv(first, tmp.msgp, (size_t) second,
101 					  tmp.msgtyp, third);
102 			break;
103 		}
104 		default:
105 			ret = sys_msgrcv (first, (struct msgbuf __user *) ptr,
106 					  (size_t)second, fifth, third);
107 			break;
108 		}
109 		break;
110 	case MSGGET:
111 		ret = sys_msgget((key_t)first, (int)second);
112 		break;
113 	case MSGCTL:
114 		ret = sys_msgctl(first, (int)second,
115 				  (struct msqid_ds __user *)ptr);
116 		break;
117 	case SHMAT: {
118 		ulong raddr;
119 		ret = do_shmat(first, (char __user *)ptr, (int)second, &raddr);
120 		if (ret)
121 			break;
122 		ret = put_user(raddr, (ulong __user *) third);
123 		break;
124 	}
125 	case SHMDT:
126 		ret = sys_shmdt((char __user *)ptr);
127 		break;
128 	case SHMGET:
129 		ret = sys_shmget(first, (size_t)second, third);
130 		break;
131 	case SHMCTL:
132 		ret = sys_shmctl(first, (int)second,
133 				 (struct shmid_ds __user *)ptr);
134 		break;
135 	}
136 
137 	return ret;
138 }
139 
140 /*
141  * sys_pipe() is the normal C calling standard for creating
142  * a pipe. It's not the way unix traditionally does this, though.
143  */
144 int sys_pipe(int __user *fildes)
145 {
146 	int fd[2];
147 	int error;
148 
149 	error = do_pipe(fd);
150 	if (!error) {
151 		if (copy_to_user(fildes, fd, 2*sizeof(int)))
152 			error = -EFAULT;
153 	}
154 	return error;
155 }
156 
157 static inline unsigned long do_mmap2(unsigned long addr, size_t len,
158 			unsigned long prot, unsigned long flags,
159 			unsigned long fd, unsigned long off, int shift)
160 {
161 	struct file * file = NULL;
162 	unsigned long ret = -EINVAL;
163 
164 	if (shift) {
165 		if (off & ((1 << shift) - 1))
166 			goto out;
167 		off >>= shift;
168 	}
169 
170 	ret = -EBADF;
171 	if (!(flags & MAP_ANONYMOUS)) {
172 		if (!(file = fget(fd)))
173 			goto out;
174 	}
175 
176 	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
177 
178 	down_write(&current->mm->mmap_sem);
179 	ret = do_mmap_pgoff(file, addr, len, prot, flags, off);
180 	up_write(&current->mm->mmap_sem);
181 	if (file)
182 		fput(file);
183 out:
184 	return ret;
185 }
186 
187 unsigned long sys_mmap2(unsigned long addr, size_t len,
188 			unsigned long prot, unsigned long flags,
189 			unsigned long fd, unsigned long pgoff)
190 {
191 	return do_mmap2(addr, len, prot, flags, fd, pgoff, PAGE_SHIFT-12);
192 }
193 
194 unsigned long sys_mmap(unsigned long addr, size_t len,
195 		       unsigned long prot, unsigned long flags,
196 		       unsigned long fd, off_t offset)
197 {
198 	return do_mmap2(addr, len, prot, flags, fd, offset, PAGE_SHIFT);
199 }
200 
201 #ifdef CONFIG_PPC32
202 /*
203  * Due to some executables calling the wrong select we sometimes
204  * get wrong args.  This determines how the args are being passed
205  * (a single ptr to them all args passed) then calls
206  * sys_select() with the appropriate args. -- Cort
207  */
208 int
209 ppc_select(int n, fd_set __user *inp, fd_set __user *outp, fd_set __user *exp, struct timeval __user *tvp)
210 {
211 	if ( (unsigned long)n >= 4096 )
212 	{
213 		unsigned long __user *buffer = (unsigned long __user *)n;
214 		if (!access_ok(VERIFY_READ, buffer, 5*sizeof(unsigned long))
215 		    || __get_user(n, buffer)
216 		    || __get_user(inp, ((fd_set __user * __user *)(buffer+1)))
217 		    || __get_user(outp, ((fd_set  __user * __user *)(buffer+2)))
218 		    || __get_user(exp, ((fd_set  __user * __user *)(buffer+3)))
219 		    || __get_user(tvp, ((struct timeval  __user * __user *)(buffer+4))))
220 			return -EFAULT;
221 	}
222 	return sys_select(n, inp, outp, exp, tvp);
223 }
224 #endif
225 
226 #ifdef CONFIG_PPC64
227 long ppc64_personality(unsigned long personality)
228 {
229 	long ret;
230 
231 	if (personality(current->personality) == PER_LINUX32
232 	    && personality == PER_LINUX)
233 		personality = PER_LINUX32;
234 	ret = sys_personality(personality);
235 	if (ret == PER_LINUX32)
236 		ret = PER_LINUX;
237 	return ret;
238 }
239 #endif
240 
241 #ifdef CONFIG_PPC64
242 #define OVERRIDE_MACHINE    (personality(current->personality) == PER_LINUX32)
243 #else
244 #define OVERRIDE_MACHINE    0
245 #endif
246 
247 static inline int override_machine(char __user *mach)
248 {
249 	if (OVERRIDE_MACHINE) {
250 		/* change ppc64 to ppc */
251 		if (__put_user(0, mach+3) || __put_user(0, mach+4))
252 			return -EFAULT;
253 	}
254 	return 0;
255 }
256 
257 long ppc_newuname(struct new_utsname __user * name)
258 {
259 	int err = 0;
260 
261 	down_read(&uts_sem);
262 	if (copy_to_user(name, &system_utsname, sizeof(*name)))
263 		err = -EFAULT;
264 	up_read(&uts_sem);
265 	if (!err)
266 		err = override_machine(name->machine);
267 	return err;
268 }
269 
270 int sys_uname(struct old_utsname __user *name)
271 {
272 	int err = 0;
273 
274 	down_read(&uts_sem);
275 	if (copy_to_user(name, &system_utsname, sizeof(*name)))
276 		err = -EFAULT;
277 	up_read(&uts_sem);
278 	if (!err)
279 		err = override_machine(name->machine);
280 	return err;
281 }
282 
283 int sys_olduname(struct oldold_utsname __user *name)
284 {
285 	int error;
286 
287 	if (!access_ok(VERIFY_WRITE, name, sizeof(struct oldold_utsname)))
288 		return -EFAULT;
289 
290 	down_read(&uts_sem);
291 	error = __copy_to_user(&name->sysname, &system_utsname.sysname,
292 			       __OLD_UTS_LEN);
293 	error |= __put_user(0, name->sysname + __OLD_UTS_LEN);
294 	error |= __copy_to_user(&name->nodename, &system_utsname.nodename,
295 				__OLD_UTS_LEN);
296 	error |= __put_user(0, name->nodename + __OLD_UTS_LEN);
297 	error |= __copy_to_user(&name->release, &system_utsname.release,
298 				__OLD_UTS_LEN);
299 	error |= __put_user(0, name->release + __OLD_UTS_LEN);
300 	error |= __copy_to_user(&name->version, &system_utsname.version,
301 				__OLD_UTS_LEN);
302 	error |= __put_user(0, name->version + __OLD_UTS_LEN);
303 	error |= __copy_to_user(&name->machine, &system_utsname.machine,
304 				__OLD_UTS_LEN);
305 	error |= override_machine(name->machine);
306 	up_read(&uts_sem);
307 
308 	return error? -EFAULT: 0;
309 }
310 
311 long ppc_fadvise64_64(int fd, int advice, u32 offset_high, u32 offset_low,
312 		      u32 len_high, u32 len_low)
313 {
314 	return sys_fadvise64(fd, (u64)offset_high << 32 | offset_low,
315 			     (u64)len_high << 32 | len_low, advice);
316 }
317 
318 void do_show_syscall(unsigned long r3, unsigned long r4, unsigned long r5,
319 		     unsigned long r6, unsigned long r7, unsigned long r8,
320 		     struct pt_regs *regs)
321 {
322 	printk("syscall %ld(%lx, %lx, %lx, %lx, %lx, %lx) regs=%p current=%p"
323 	       " cpu=%d\n", regs->gpr[0], r3, r4, r5, r6, r7, r8, regs,
324 	       current, smp_processor_id());
325 }
326 
327 void do_show_syscall_exit(unsigned long r3)
328 {
329 	printk(" -> %lx, current=%p cpu=%d\n", r3, current, smp_processor_id());
330 }
331