xref: /linux/arch/powerpc/kernel/syscalls.c (revision 95d465fd750897ab32462a6702fbfe1b122cbbc0)
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/syscalls.h>
44 #include <asm/time.h>
45 #include <asm/unistd.h>
46 
47 /*
48  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
49  *
50  * This is really horribly ugly.
51  */
52 int sys_ipc(uint call, int first, unsigned long second, long third,
53 	    void __user *ptr, long fifth)
54 {
55 	int version, ret;
56 
57 	version = call >> 16; /* hack for backward compatibility */
58 	call &= 0xffff;
59 
60 	ret = -ENOSYS;
61 	switch (call) {
62 	case SEMOP:
63 		ret = sys_semtimedop(first, (struct sembuf __user *)ptr,
64 				      (unsigned)second, NULL);
65 		break;
66 	case SEMTIMEDOP:
67 		ret = sys_semtimedop(first, (struct sembuf __user *)ptr,
68 				      (unsigned)second,
69 				      (const struct timespec __user *) fifth);
70 		break;
71 	case SEMGET:
72 		ret = sys_semget (first, (int)second, third);
73 		break;
74 	case SEMCTL: {
75 		union semun fourth;
76 
77 		ret = -EINVAL;
78 		if (!ptr)
79 			break;
80 		if ((ret = get_user(fourth.__pad, (void __user * __user *)ptr)))
81 			break;
82 		ret = sys_semctl(first, (int)second, third, fourth);
83 		break;
84 	}
85 	case MSGSND:
86 		ret = sys_msgsnd(first, (struct msgbuf __user *)ptr,
87 				 (size_t)second, third);
88 		break;
89 	case MSGRCV:
90 		switch (version) {
91 		case 0: {
92 			struct ipc_kludge tmp;
93 
94 			ret = -EINVAL;
95 			if (!ptr)
96 				break;
97 			if ((ret = copy_from_user(&tmp,
98 						(struct ipc_kludge __user *) ptr,
99 						sizeof (tmp)) ? -EFAULT : 0))
100 				break;
101 			ret = sys_msgrcv(first, tmp.msgp, (size_t) second,
102 					  tmp.msgtyp, third);
103 			break;
104 		}
105 		default:
106 			ret = sys_msgrcv (first, (struct msgbuf __user *) ptr,
107 					  (size_t)second, fifth, third);
108 			break;
109 		}
110 		break;
111 	case MSGGET:
112 		ret = sys_msgget((key_t)first, (int)second);
113 		break;
114 	case MSGCTL:
115 		ret = sys_msgctl(first, (int)second,
116 				  (struct msqid_ds __user *)ptr);
117 		break;
118 	case SHMAT: {
119 		ulong raddr;
120 		ret = do_shmat(first, (char __user *)ptr, (int)second, &raddr);
121 		if (ret)
122 			break;
123 		ret = put_user(raddr, (ulong __user *) third);
124 		break;
125 	}
126 	case SHMDT:
127 		ret = sys_shmdt((char __user *)ptr);
128 		break;
129 	case SHMGET:
130 		ret = sys_shmget(first, (size_t)second, third);
131 		break;
132 	case SHMCTL:
133 		ret = sys_shmctl(first, (int)second,
134 				 (struct shmid_ds __user *)ptr);
135 		break;
136 	}
137 
138 	return ret;
139 }
140 
141 /*
142  * sys_pipe() is the normal C calling standard for creating
143  * a pipe. It's not the way unix traditionally does this, though.
144  */
145 int sys_pipe(int __user *fildes)
146 {
147 	int fd[2];
148 	int error;
149 
150 	error = do_pipe(fd);
151 	if (!error) {
152 		if (copy_to_user(fildes, fd, 2*sizeof(int)))
153 			error = -EFAULT;
154 	}
155 	return error;
156 }
157 
158 static inline unsigned long do_mmap2(unsigned long addr, size_t len,
159 			unsigned long prot, unsigned long flags,
160 			unsigned long fd, unsigned long off, int shift)
161 {
162 	struct file * file = NULL;
163 	unsigned long ret = -EINVAL;
164 
165 	if (shift) {
166 		if (off & ((1 << shift) - 1))
167 			goto out;
168 		off >>= shift;
169 	}
170 
171 	ret = -EBADF;
172 	if (!(flags & MAP_ANONYMOUS)) {
173 		if (!(file = fget(fd)))
174 			goto out;
175 	}
176 
177 	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
178 
179 	down_write(&current->mm->mmap_sem);
180 	ret = do_mmap_pgoff(file, addr, len, prot, flags, off);
181 	up_write(&current->mm->mmap_sem);
182 	if (file)
183 		fput(file);
184 out:
185 	return ret;
186 }
187 
188 unsigned long sys_mmap2(unsigned long addr, size_t len,
189 			unsigned long prot, unsigned long flags,
190 			unsigned long fd, unsigned long pgoff)
191 {
192 	return do_mmap2(addr, len, prot, flags, fd, pgoff, PAGE_SHIFT-12);
193 }
194 
195 unsigned long sys_mmap(unsigned long addr, size_t len,
196 		       unsigned long prot, unsigned long flags,
197 		       unsigned long fd, off_t offset)
198 {
199 	return do_mmap2(addr, len, prot, flags, fd, offset, PAGE_SHIFT);
200 }
201 
202 #ifdef CONFIG_PPC32
203 /*
204  * Due to some executables calling the wrong select we sometimes
205  * get wrong args.  This determines how the args are being passed
206  * (a single ptr to them all args passed) then calls
207  * sys_select() with the appropriate args. -- Cort
208  */
209 int
210 ppc_select(int n, fd_set __user *inp, fd_set __user *outp, fd_set __user *exp, struct timeval __user *tvp)
211 {
212 	if ( (unsigned long)n >= 4096 )
213 	{
214 		unsigned long __user *buffer = (unsigned long __user *)n;
215 		if (!access_ok(VERIFY_READ, buffer, 5*sizeof(unsigned long))
216 		    || __get_user(n, buffer)
217 		    || __get_user(inp, ((fd_set __user * __user *)(buffer+1)))
218 		    || __get_user(outp, ((fd_set  __user * __user *)(buffer+2)))
219 		    || __get_user(exp, ((fd_set  __user * __user *)(buffer+3)))
220 		    || __get_user(tvp, ((struct timeval  __user * __user *)(buffer+4))))
221 			return -EFAULT;
222 	}
223 	return sys_select(n, inp, outp, exp, tvp);
224 }
225 #endif
226 
227 #ifdef CONFIG_PPC64
228 long ppc64_personality(unsigned long personality)
229 {
230 	long ret;
231 
232 	if (personality(current->personality) == PER_LINUX32
233 	    && personality == PER_LINUX)
234 		personality = PER_LINUX32;
235 	ret = sys_personality(personality);
236 	if (ret == PER_LINUX32)
237 		ret = PER_LINUX;
238 	return ret;
239 }
240 #endif
241 
242 #ifdef CONFIG_PPC64
243 #define OVERRIDE_MACHINE    (personality(current->personality) == PER_LINUX32)
244 #else
245 #define OVERRIDE_MACHINE    0
246 #endif
247 
248 static inline int override_machine(char __user *mach)
249 {
250 	if (OVERRIDE_MACHINE) {
251 		/* change ppc64 to ppc */
252 		if (__put_user(0, mach+3) || __put_user(0, mach+4))
253 			return -EFAULT;
254 	}
255 	return 0;
256 }
257 
258 long ppc_newuname(struct new_utsname __user * name)
259 {
260 	int err = 0;
261 
262 	down_read(&uts_sem);
263 	if (copy_to_user(name, &system_utsname, sizeof(*name)))
264 		err = -EFAULT;
265 	up_read(&uts_sem);
266 	if (!err)
267 		err = override_machine(name->machine);
268 	return err;
269 }
270 
271 int sys_uname(struct old_utsname __user *name)
272 {
273 	int err = 0;
274 
275 	down_read(&uts_sem);
276 	if (copy_to_user(name, &system_utsname, sizeof(*name)))
277 		err = -EFAULT;
278 	up_read(&uts_sem);
279 	if (!err)
280 		err = override_machine(name->machine);
281 	return err;
282 }
283 
284 int sys_olduname(struct oldold_utsname __user *name)
285 {
286 	int error;
287 
288 	if (!access_ok(VERIFY_WRITE, name, sizeof(struct oldold_utsname)))
289 		return -EFAULT;
290 
291 	down_read(&uts_sem);
292 	error = __copy_to_user(&name->sysname, &system_utsname.sysname,
293 			       __OLD_UTS_LEN);
294 	error |= __put_user(0, name->sysname + __OLD_UTS_LEN);
295 	error |= __copy_to_user(&name->nodename, &system_utsname.nodename,
296 				__OLD_UTS_LEN);
297 	error |= __put_user(0, name->nodename + __OLD_UTS_LEN);
298 	error |= __copy_to_user(&name->release, &system_utsname.release,
299 				__OLD_UTS_LEN);
300 	error |= __put_user(0, name->release + __OLD_UTS_LEN);
301 	error |= __copy_to_user(&name->version, &system_utsname.version,
302 				__OLD_UTS_LEN);
303 	error |= __put_user(0, name->version + __OLD_UTS_LEN);
304 	error |= __copy_to_user(&name->machine, &system_utsname.machine,
305 				__OLD_UTS_LEN);
306 	error |= override_machine(name->machine);
307 	up_read(&uts_sem);
308 
309 	return error? -EFAULT: 0;
310 }
311 
312 long ppc_fadvise64_64(int fd, int advice, u32 offset_high, u32 offset_low,
313 		      u32 len_high, u32 len_low)
314 {
315 	return sys_fadvise64(fd, (u64)offset_high << 32 | offset_low,
316 			     (u64)len_high << 32 | len_low, advice);
317 }
318 
319 void do_show_syscall(unsigned long r3, unsigned long r4, unsigned long r5,
320 		     unsigned long r6, unsigned long r7, unsigned long r8,
321 		     struct pt_regs *regs)
322 {
323 	printk("syscall %ld(%lx, %lx, %lx, %lx, %lx, %lx) regs=%p current=%p"
324 	       " cpu=%d\n", regs->gpr[0], r3, r4, r5, r6, r7, r8, regs,
325 	       current, smp_processor_id());
326 }
327 
328 void do_show_syscall_exit(unsigned long r3)
329 {
330 	printk(" -> %lx, current=%p cpu=%d\n", r3, current, smp_processor_id());
331 }
332