xref: /linux/arch/mips/kernel/syscall.c (revision d8327c784b51b57dac2c26cfad87dce0d68dfd98)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 1995, 1996, 1997, 2000, 2001, 05 by Ralf Baechle
7  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
8  * Copyright (C) 2001 MIPS Technologies, Inc.
9  */
10 #include <linux/config.h>
11 #include <linux/a.out.h>
12 #include <linux/capability.h>
13 #include <linux/errno.h>
14 #include <linux/linkage.h>
15 #include <linux/mm.h>
16 #include <linux/smp.h>
17 #include <linux/smp_lock.h>
18 #include <linux/mman.h>
19 #include <linux/ptrace.h>
20 #include <linux/sched.h>
21 #include <linux/string.h>
22 #include <linux/syscalls.h>
23 #include <linux/file.h>
24 #include <linux/slab.h>
25 #include <linux/utsname.h>
26 #include <linux/unistd.h>
27 #include <linux/sem.h>
28 #include <linux/msg.h>
29 #include <linux/shm.h>
30 #include <linux/compiler.h>
31 #include <linux/module.h>
32 
33 #include <asm/branch.h>
34 #include <asm/cachectl.h>
35 #include <asm/cacheflush.h>
36 #include <asm/ipc.h>
37 #include <asm/asm-offsets.h>
38 #include <asm/signal.h>
39 #include <asm/sim.h>
40 #include <asm/shmparam.h>
41 #include <asm/sysmips.h>
42 #include <asm/uaccess.h>
43 
44 asmlinkage int sys_pipe(nabi_no_regargs volatile struct pt_regs regs)
45 {
46 	int fd[2];
47 	int error, res;
48 
49 	error = do_pipe(fd);
50 	if (error) {
51 		res = error;
52 		goto out;
53 	}
54 	regs.regs[3] = fd[1];
55 	res = fd[0];
56 out:
57 	return res;
58 }
59 
60 unsigned long shm_align_mask = PAGE_SIZE - 1;	/* Sane caches */
61 
62 EXPORT_SYMBOL(shm_align_mask);
63 
64 #define COLOUR_ALIGN(addr,pgoff)				\
65 	((((addr) + shm_align_mask) & ~shm_align_mask) +	\
66 	 (((pgoff) << PAGE_SHIFT) & shm_align_mask))
67 
68 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
69 	unsigned long len, unsigned long pgoff, unsigned long flags)
70 {
71 	struct vm_area_struct * vmm;
72 	int do_color_align;
73 	unsigned long task_size;
74 
75 	task_size = STACK_TOP;
76 
77 	if (flags & MAP_FIXED) {
78 		/*
79 		 * We do not accept a shared mapping if it would violate
80 		 * cache aliasing constraints.
81 		 */
82 		if ((flags & MAP_SHARED) && (addr & shm_align_mask))
83 			return -EINVAL;
84 		return addr;
85 	}
86 
87 	if (len > task_size)
88 		return -ENOMEM;
89 	do_color_align = 0;
90 	if (filp || (flags & MAP_SHARED))
91 		do_color_align = 1;
92 	if (addr) {
93 		if (do_color_align)
94 			addr = COLOUR_ALIGN(addr, pgoff);
95 		else
96 			addr = PAGE_ALIGN(addr);
97 		vmm = find_vma(current->mm, addr);
98 		if (task_size - len >= addr &&
99 		    (!vmm || addr + len <= vmm->vm_start))
100 			return addr;
101 	}
102 	addr = TASK_UNMAPPED_BASE;
103 	if (do_color_align)
104 		addr = COLOUR_ALIGN(addr, pgoff);
105 	else
106 		addr = PAGE_ALIGN(addr);
107 
108 	for (vmm = find_vma(current->mm, addr); ; vmm = vmm->vm_next) {
109 		/* At this point:  (!vmm || addr < vmm->vm_end). */
110 		if (task_size - len < addr)
111 			return -ENOMEM;
112 		if (!vmm || addr + len <= vmm->vm_start)
113 			return addr;
114 		addr = vmm->vm_end;
115 		if (do_color_align)
116 			addr = COLOUR_ALIGN(addr, pgoff);
117 	}
118 }
119 
120 /* common code for old and new mmaps */
121 static inline unsigned long
122 do_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
123         unsigned long flags, unsigned long fd, unsigned long pgoff)
124 {
125 	unsigned long error = -EBADF;
126 	struct file * file = NULL;
127 
128 	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
129 	if (!(flags & MAP_ANONYMOUS)) {
130 		file = fget(fd);
131 		if (!file)
132 			goto out;
133 	}
134 
135 	down_write(&current->mm->mmap_sem);
136 	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
137 	up_write(&current->mm->mmap_sem);
138 
139 	if (file)
140 		fput(file);
141 out:
142 	return error;
143 }
144 
145 asmlinkage unsigned long
146 old_mmap(unsigned long addr, unsigned long len, int prot,
147 	int flags, int fd, off_t offset)
148 {
149 	unsigned long result;
150 
151 	result = -EINVAL;
152 	if (offset & ~PAGE_MASK)
153 		goto out;
154 
155 	result = do_mmap2(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
156 
157 out:
158 	return result;
159 }
160 
161 asmlinkage unsigned long
162 sys_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
163           unsigned long flags, unsigned long fd, unsigned long pgoff)
164 {
165 	return do_mmap2(addr, len, prot, flags, fd, pgoff);
166 }
167 
168 save_static_function(sys_fork);
169 __attribute_used__ noinline static int
170 _sys_fork(nabi_no_regargs struct pt_regs regs)
171 {
172 	return do_fork(SIGCHLD, regs.regs[29], &regs, 0, NULL, NULL);
173 }
174 
175 save_static_function(sys_clone);
176 __attribute_used__ noinline static int
177 _sys_clone(nabi_no_regargs struct pt_regs regs)
178 {
179 	unsigned long clone_flags;
180 	unsigned long newsp;
181 	int __user *parent_tidptr, *child_tidptr;
182 
183 	clone_flags = regs.regs[4];
184 	newsp = regs.regs[5];
185 	if (!newsp)
186 		newsp = regs.regs[29];
187 	parent_tidptr = (int __user *) regs.regs[6];
188 #ifdef CONFIG_32BIT
189 	/* We need to fetch the fifth argument off the stack.  */
190 	child_tidptr = NULL;
191 	if (clone_flags & (CLONE_CHILD_SETTID | CLONE_CHILD_CLEARTID)) {
192 		int __user *__user *usp = (int __user *__user *) regs.regs[29];
193 		if (regs.regs[2] == __NR_syscall) {
194 			if (get_user (child_tidptr, &usp[5]))
195 				return -EFAULT;
196 		}
197 		else if (get_user (child_tidptr, &usp[4]))
198 			return -EFAULT;
199 	}
200 #else
201 	child_tidptr = (int __user *) regs.regs[8];
202 #endif
203 	return do_fork(clone_flags, newsp, &regs, 0,
204 	               parent_tidptr, child_tidptr);
205 }
206 
207 /*
208  * sys_execve() executes a new program.
209  */
210 asmlinkage int sys_execve(nabi_no_regargs struct pt_regs regs)
211 {
212 	int error;
213 	char * filename;
214 
215 	filename = getname((char __user *) (long)regs.regs[4]);
216 	error = PTR_ERR(filename);
217 	if (IS_ERR(filename))
218 		goto out;
219 	error = do_execve(filename, (char __user *__user *) (long)regs.regs[5],
220 	                  (char __user *__user *) (long)regs.regs[6], &regs);
221 	putname(filename);
222 
223 out:
224 	return error;
225 }
226 
227 /*
228  * Compacrapability ...
229  */
230 asmlinkage int sys_uname(struct old_utsname __user * name)
231 {
232 	if (name && !copy_to_user(name, &system_utsname, sizeof (*name)))
233 		return 0;
234 	return -EFAULT;
235 }
236 
237 /*
238  * Compacrapability ...
239  */
240 asmlinkage int sys_olduname(struct oldold_utsname __user * name)
241 {
242 	int error;
243 
244 	if (!name)
245 		return -EFAULT;
246 	if (!access_ok(VERIFY_WRITE,name,sizeof(struct oldold_utsname)))
247 		return -EFAULT;
248 
249 	error = __copy_to_user(&name->sysname,&system_utsname.sysname,__OLD_UTS_LEN);
250 	error -= __put_user(0,name->sysname+__OLD_UTS_LEN);
251 	error -= __copy_to_user(&name->nodename,&system_utsname.nodename,__OLD_UTS_LEN);
252 	error -= __put_user(0,name->nodename+__OLD_UTS_LEN);
253 	error -= __copy_to_user(&name->release,&system_utsname.release,__OLD_UTS_LEN);
254 	error -= __put_user(0,name->release+__OLD_UTS_LEN);
255 	error -= __copy_to_user(&name->version,&system_utsname.version,__OLD_UTS_LEN);
256 	error -= __put_user(0,name->version+__OLD_UTS_LEN);
257 	error -= __copy_to_user(&name->machine,&system_utsname.machine,__OLD_UTS_LEN);
258 	error = __put_user(0,name->machine+__OLD_UTS_LEN);
259 	error = error ? -EFAULT : 0;
260 
261 	return error;
262 }
263 
264 void sys_set_thread_area(unsigned long addr)
265 {
266 	struct thread_info *ti = task_thread_info(current);
267 
268 	ti->tp_value = addr;
269 
270 	/* If some future MIPS implementation has this register in hardware,
271 	 * we will need to update it here (and in context switches).  */
272 }
273 
274 asmlinkage int _sys_sysmips(int cmd, long arg1, int arg2, int arg3)
275 {
276 	int	tmp, len;
277 	char	__user *name;
278 
279 	switch(cmd) {
280 	case SETNAME: {
281 		char nodename[__NEW_UTS_LEN + 1];
282 
283 		if (!capable(CAP_SYS_ADMIN))
284 			return -EPERM;
285 
286 		name = (char __user *) arg1;
287 
288 		len = strncpy_from_user(nodename, name, __NEW_UTS_LEN);
289 		if (len < 0)
290 			return -EFAULT;
291 
292 		down_write(&uts_sem);
293 		strncpy(system_utsname.nodename, nodename, len);
294 		nodename[__NEW_UTS_LEN] = '\0';
295 		strlcpy(system_utsname.nodename, nodename,
296 		        sizeof(system_utsname.nodename));
297 		up_write(&uts_sem);
298 		return 0;
299 	}
300 
301 	case MIPS_ATOMIC_SET:
302 		printk(KERN_CRIT "How did I get here?\n");
303 		return -EINVAL;
304 
305 	case MIPS_FIXADE:
306 		tmp = current->thread.mflags & ~3;
307 		current->thread.mflags = tmp | (arg1 & 3);
308 		return 0;
309 
310 	case FLUSH_CACHE:
311 		__flush_cache_all();
312 		return 0;
313 
314 	case MIPS_RDNVRAM:
315 		return -EIO;
316 	}
317 
318 	return -EINVAL;
319 }
320 
321 /*
322  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
323  *
324  * This is really horribly ugly.
325  */
326 asmlinkage int sys_ipc (uint call, int first, int second,
327 			unsigned long third, void __user *ptr, long fifth)
328 {
329 	int version, ret;
330 
331 	version = call >> 16; /* hack for backward compatibility */
332 	call &= 0xffff;
333 
334 	switch (call) {
335 	case SEMOP:
336 		return sys_semtimedop (first, (struct sembuf __user *)ptr,
337 		                       second, NULL);
338 	case SEMTIMEDOP:
339 		return sys_semtimedop (first, (struct sembuf __user *)ptr,
340 				       second,
341 				       (const struct timespec __user *)fifth);
342 	case SEMGET:
343 		return sys_semget (first, second, third);
344 	case SEMCTL: {
345 		union semun fourth;
346 		if (!ptr)
347 			return -EINVAL;
348 		if (get_user(fourth.__pad, (void *__user *) ptr))
349 			return -EFAULT;
350 		return sys_semctl (first, second, third, fourth);
351 	}
352 
353 	case MSGSND:
354 		return sys_msgsnd (first, (struct msgbuf __user *) ptr,
355 				   second, third);
356 	case MSGRCV:
357 		switch (version) {
358 		case 0: {
359 			struct ipc_kludge tmp;
360 			if (!ptr)
361 				return -EINVAL;
362 
363 			if (copy_from_user(&tmp,
364 					   (struct ipc_kludge __user *) ptr,
365 					   sizeof (tmp)))
366 				return -EFAULT;
367 			return sys_msgrcv (first, tmp.msgp, second,
368 					   tmp.msgtyp, third);
369 		}
370 		default:
371 			return sys_msgrcv (first,
372 					   (struct msgbuf __user *) ptr,
373 					   second, fifth, third);
374 		}
375 	case MSGGET:
376 		return sys_msgget ((key_t) first, second);
377 	case MSGCTL:
378 		return sys_msgctl (first, second,
379 				   (struct msqid_ds __user *) ptr);
380 
381 	case SHMAT:
382 		switch (version) {
383 		default: {
384 			ulong raddr;
385 			ret = do_shmat (first, (char __user *) ptr, second,
386 					&raddr);
387 			if (ret)
388 				return ret;
389 			return put_user (raddr, (ulong __user *) third);
390 		}
391 		case 1:	/* iBCS2 emulator entry point */
392 			if (!segment_eq(get_fs(), get_ds()))
393 				return -EINVAL;
394 			return do_shmat (first, (char __user *) ptr, second,
395 					 (ulong *) third);
396 		}
397 	case SHMDT:
398 		return sys_shmdt ((char __user *)ptr);
399 	case SHMGET:
400 		return sys_shmget (first, second, third);
401 	case SHMCTL:
402 		return sys_shmctl (first, second,
403 				   (struct shmid_ds __user *) ptr);
404 	default:
405 		return -ENOSYS;
406 	}
407 }
408 
409 /*
410  * No implemented yet ...
411  */
412 asmlinkage int sys_cachectl(char *addr, int nbytes, int op)
413 {
414 	return -ENOSYS;
415 }
416 
417 /*
418  * If we ever come here the user sp is bad.  Zap the process right away.
419  * Due to the bad stack signaling wouldn't work.
420  */
421 asmlinkage void bad_stack(void)
422 {
423 	do_exit(SIGSEGV);
424 }
425