xref: /openbmc/linux/arch/powerpc/kernel/syscalls.c (revision 22246614)
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/fs.h>
27 #include <linux/smp.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/syscalls.h>
42 #include <asm/time.h>
43 #include <asm/unistd.h>
44 
45 /*
46  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
47  *
48  * This is really horribly ugly.
49  */
50 int sys_ipc(uint call, int first, unsigned long second, long third,
51 	    void __user *ptr, long fifth)
52 {
53 	int version, ret;
54 
55 	version = call >> 16; /* hack for backward compatibility */
56 	call &= 0xffff;
57 
58 	ret = -ENOSYS;
59 	switch (call) {
60 	case SEMOP:
61 		ret = sys_semtimedop(first, (struct sembuf __user *)ptr,
62 				      (unsigned)second, NULL);
63 		break;
64 	case SEMTIMEDOP:
65 		ret = sys_semtimedop(first, (struct sembuf __user *)ptr,
66 				      (unsigned)second,
67 				      (const struct timespec __user *) fifth);
68 		break;
69 	case SEMGET:
70 		ret = sys_semget (first, (int)second, third);
71 		break;
72 	case SEMCTL: {
73 		union semun fourth;
74 
75 		ret = -EINVAL;
76 		if (!ptr)
77 			break;
78 		if ((ret = get_user(fourth.__pad, (void __user * __user *)ptr)))
79 			break;
80 		ret = sys_semctl(first, (int)second, third, fourth);
81 		break;
82 	}
83 	case MSGSND:
84 		ret = sys_msgsnd(first, (struct msgbuf __user *)ptr,
85 				 (size_t)second, third);
86 		break;
87 	case MSGRCV:
88 		switch (version) {
89 		case 0: {
90 			struct ipc_kludge tmp;
91 
92 			ret = -EINVAL;
93 			if (!ptr)
94 				break;
95 			if ((ret = copy_from_user(&tmp,
96 						(struct ipc_kludge __user *) ptr,
97 						sizeof (tmp)) ? -EFAULT : 0))
98 				break;
99 			ret = sys_msgrcv(first, tmp.msgp, (size_t) second,
100 					  tmp.msgtyp, third);
101 			break;
102 		}
103 		default:
104 			ret = sys_msgrcv (first, (struct msgbuf __user *) ptr,
105 					  (size_t)second, fifth, third);
106 			break;
107 		}
108 		break;
109 	case MSGGET:
110 		ret = sys_msgget((key_t)first, (int)second);
111 		break;
112 	case MSGCTL:
113 		ret = sys_msgctl(first, (int)second,
114 				  (struct msqid_ds __user *)ptr);
115 		break;
116 	case SHMAT: {
117 		ulong raddr;
118 		ret = do_shmat(first, (char __user *)ptr, (int)second, &raddr);
119 		if (ret)
120 			break;
121 		ret = put_user(raddr, (ulong __user *) third);
122 		break;
123 	}
124 	case SHMDT:
125 		ret = sys_shmdt((char __user *)ptr);
126 		break;
127 	case SHMGET:
128 		ret = sys_shmget(first, (size_t)second, third);
129 		break;
130 	case SHMCTL:
131 		ret = sys_shmctl(first, (int)second,
132 				 (struct shmid_ds __user *)ptr);
133 		break;
134 	}
135 
136 	return ret;
137 }
138 
139 static inline unsigned long do_mmap2(unsigned long addr, size_t len,
140 			unsigned long prot, unsigned long flags,
141 			unsigned long fd, unsigned long off, int shift)
142 {
143 	struct file * file = NULL;
144 	unsigned long ret = -EINVAL;
145 
146 	if (shift) {
147 		if (off & ((1 << shift) - 1))
148 			goto out;
149 		off >>= shift;
150 	}
151 
152 	ret = -EBADF;
153 	if (!(flags & MAP_ANONYMOUS)) {
154 		if (!(file = fget(fd)))
155 			goto out;
156 	}
157 
158 	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
159 
160 	down_write(&current->mm->mmap_sem);
161 	ret = do_mmap_pgoff(file, addr, len, prot, flags, off);
162 	up_write(&current->mm->mmap_sem);
163 	if (file)
164 		fput(file);
165 out:
166 	return ret;
167 }
168 
169 unsigned long sys_mmap2(unsigned long addr, size_t len,
170 			unsigned long prot, unsigned long flags,
171 			unsigned long fd, unsigned long pgoff)
172 {
173 	return do_mmap2(addr, len, prot, flags, fd, pgoff, PAGE_SHIFT-12);
174 }
175 
176 unsigned long sys_mmap(unsigned long addr, size_t len,
177 		       unsigned long prot, unsigned long flags,
178 		       unsigned long fd, off_t offset)
179 {
180 	return do_mmap2(addr, len, prot, flags, fd, offset, PAGE_SHIFT);
181 }
182 
183 #ifdef CONFIG_PPC32
184 /*
185  * Due to some executables calling the wrong select we sometimes
186  * get wrong args.  This determines how the args are being passed
187  * (a single ptr to them all args passed) then calls
188  * sys_select() with the appropriate args. -- Cort
189  */
190 int
191 ppc_select(int n, fd_set __user *inp, fd_set __user *outp, fd_set __user *exp, struct timeval __user *tvp)
192 {
193 	if ( (unsigned long)n >= 4096 )
194 	{
195 		unsigned long __user *buffer = (unsigned long __user *)n;
196 		if (!access_ok(VERIFY_READ, buffer, 5*sizeof(unsigned long))
197 		    || __get_user(n, buffer)
198 		    || __get_user(inp, ((fd_set __user * __user *)(buffer+1)))
199 		    || __get_user(outp, ((fd_set  __user * __user *)(buffer+2)))
200 		    || __get_user(exp, ((fd_set  __user * __user *)(buffer+3)))
201 		    || __get_user(tvp, ((struct timeval  __user * __user *)(buffer+4))))
202 			return -EFAULT;
203 	}
204 	return sys_select(n, inp, outp, exp, tvp);
205 }
206 #endif
207 
208 #ifdef CONFIG_PPC64
209 long ppc64_personality(unsigned long personality)
210 {
211 	long ret;
212 
213 	if (personality(current->personality) == PER_LINUX32
214 	    && personality == PER_LINUX)
215 		personality = PER_LINUX32;
216 	ret = sys_personality(personality);
217 	if (ret == PER_LINUX32)
218 		ret = PER_LINUX;
219 	return ret;
220 }
221 #endif
222 
223 #ifdef CONFIG_PPC64
224 #define OVERRIDE_MACHINE    (personality(current->personality) == PER_LINUX32)
225 #else
226 #define OVERRIDE_MACHINE    0
227 #endif
228 
229 static inline int override_machine(char __user *mach)
230 {
231 	if (OVERRIDE_MACHINE) {
232 		/* change ppc64 to ppc */
233 		if (__put_user(0, mach+3) || __put_user(0, mach+4))
234 			return -EFAULT;
235 	}
236 	return 0;
237 }
238 
239 long ppc_newuname(struct new_utsname __user * name)
240 {
241 	int err = 0;
242 
243 	down_read(&uts_sem);
244 	if (copy_to_user(name, utsname(), sizeof(*name)))
245 		err = -EFAULT;
246 	up_read(&uts_sem);
247 	if (!err)
248 		err = override_machine(name->machine);
249 	return err;
250 }
251 
252 int sys_uname(struct old_utsname __user *name)
253 {
254 	int err = 0;
255 
256 	down_read(&uts_sem);
257 	if (copy_to_user(name, utsname(), sizeof(*name)))
258 		err = -EFAULT;
259 	up_read(&uts_sem);
260 	if (!err)
261 		err = override_machine(name->machine);
262 	return err;
263 }
264 
265 int sys_olduname(struct oldold_utsname __user *name)
266 {
267 	int error;
268 
269 	if (!access_ok(VERIFY_WRITE, name, sizeof(struct oldold_utsname)))
270 		return -EFAULT;
271 
272 	down_read(&uts_sem);
273 	error = __copy_to_user(&name->sysname, &utsname()->sysname,
274 			       __OLD_UTS_LEN);
275 	error |= __put_user(0, name->sysname + __OLD_UTS_LEN);
276 	error |= __copy_to_user(&name->nodename, &utsname()->nodename,
277 				__OLD_UTS_LEN);
278 	error |= __put_user(0, name->nodename + __OLD_UTS_LEN);
279 	error |= __copy_to_user(&name->release, &utsname()->release,
280 				__OLD_UTS_LEN);
281 	error |= __put_user(0, name->release + __OLD_UTS_LEN);
282 	error |= __copy_to_user(&name->version, &utsname()->version,
283 				__OLD_UTS_LEN);
284 	error |= __put_user(0, name->version + __OLD_UTS_LEN);
285 	error |= __copy_to_user(&name->machine, &utsname()->machine,
286 				__OLD_UTS_LEN);
287 	error |= override_machine(name->machine);
288 	up_read(&uts_sem);
289 
290 	return error? -EFAULT: 0;
291 }
292 
293 long ppc_fadvise64_64(int fd, int advice, u32 offset_high, u32 offset_low,
294 		      u32 len_high, u32 len_low)
295 {
296 	return sys_fadvise64(fd, (u64)offset_high << 32 | offset_low,
297 			     (u64)len_high << 32 | len_low, advice);
298 }
299 
300 void do_show_syscall(unsigned long r3, unsigned long r4, unsigned long r5,
301 		     unsigned long r6, unsigned long r7, unsigned long r8,
302 		     struct pt_regs *regs)
303 {
304 	printk("syscall %ld(%lx, %lx, %lx, %lx, %lx, %lx) regs=%p current=%p"
305 	       " cpu=%d\n", regs->gpr[0], r3, r4, r5, r6, r7, r8, regs,
306 	       current, smp_processor_id());
307 }
308 
309 void do_show_syscall_exit(unsigned long r3)
310 {
311 	printk(" -> %lx, current=%p cpu=%d\n", r3, current, smp_processor_id());
312 }
313