xref: /linux/arch/mips/kernel/syscall.c (revision f3d9478b2ce468c3115b02ecae7e975990697f15)
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 	if (pgoff & (~PAGE_MASK >> 12))
166 		return -EINVAL;
167 
168 	return do_mmap2(addr, len, prot, flags, fd, pgoff >> (PAGE_SHIFT-12));
169 }
170 
171 save_static_function(sys_fork);
172 __attribute_used__ noinline static int
173 _sys_fork(nabi_no_regargs struct pt_regs regs)
174 {
175 	return do_fork(SIGCHLD, regs.regs[29], &regs, 0, NULL, NULL);
176 }
177 
178 save_static_function(sys_clone);
179 __attribute_used__ noinline static int
180 _sys_clone(nabi_no_regargs struct pt_regs regs)
181 {
182 	unsigned long clone_flags;
183 	unsigned long newsp;
184 	int __user *parent_tidptr, *child_tidptr;
185 
186 	clone_flags = regs.regs[4];
187 	newsp = regs.regs[5];
188 	if (!newsp)
189 		newsp = regs.regs[29];
190 	parent_tidptr = (int __user *) regs.regs[6];
191 #ifdef CONFIG_32BIT
192 	/* We need to fetch the fifth argument off the stack.  */
193 	child_tidptr = NULL;
194 	if (clone_flags & (CLONE_CHILD_SETTID | CLONE_CHILD_CLEARTID)) {
195 		int __user *__user *usp = (int __user *__user *) regs.regs[29];
196 		if (regs.regs[2] == __NR_syscall) {
197 			if (get_user (child_tidptr, &usp[5]))
198 				return -EFAULT;
199 		}
200 		else if (get_user (child_tidptr, &usp[4]))
201 			return -EFAULT;
202 	}
203 #else
204 	child_tidptr = (int __user *) regs.regs[8];
205 #endif
206 	return do_fork(clone_flags, newsp, &regs, 0,
207 	               parent_tidptr, child_tidptr);
208 }
209 
210 /*
211  * sys_execve() executes a new program.
212  */
213 asmlinkage int sys_execve(nabi_no_regargs struct pt_regs regs)
214 {
215 	int error;
216 	char * filename;
217 
218 	filename = getname((char __user *) (long)regs.regs[4]);
219 	error = PTR_ERR(filename);
220 	if (IS_ERR(filename))
221 		goto out;
222 	error = do_execve(filename, (char __user *__user *) (long)regs.regs[5],
223 	                  (char __user *__user *) (long)regs.regs[6], &regs);
224 	putname(filename);
225 
226 out:
227 	return error;
228 }
229 
230 /*
231  * Compacrapability ...
232  */
233 asmlinkage int sys_uname(struct old_utsname __user * name)
234 {
235 	if (name && !copy_to_user(name, &system_utsname, sizeof (*name)))
236 		return 0;
237 	return -EFAULT;
238 }
239 
240 /*
241  * Compacrapability ...
242  */
243 asmlinkage int sys_olduname(struct oldold_utsname __user * name)
244 {
245 	int error;
246 
247 	if (!name)
248 		return -EFAULT;
249 	if (!access_ok(VERIFY_WRITE,name,sizeof(struct oldold_utsname)))
250 		return -EFAULT;
251 
252 	error = __copy_to_user(&name->sysname,&system_utsname.sysname,__OLD_UTS_LEN);
253 	error -= __put_user(0,name->sysname+__OLD_UTS_LEN);
254 	error -= __copy_to_user(&name->nodename,&system_utsname.nodename,__OLD_UTS_LEN);
255 	error -= __put_user(0,name->nodename+__OLD_UTS_LEN);
256 	error -= __copy_to_user(&name->release,&system_utsname.release,__OLD_UTS_LEN);
257 	error -= __put_user(0,name->release+__OLD_UTS_LEN);
258 	error -= __copy_to_user(&name->version,&system_utsname.version,__OLD_UTS_LEN);
259 	error -= __put_user(0,name->version+__OLD_UTS_LEN);
260 	error -= __copy_to_user(&name->machine,&system_utsname.machine,__OLD_UTS_LEN);
261 	error = __put_user(0,name->machine+__OLD_UTS_LEN);
262 	error = error ? -EFAULT : 0;
263 
264 	return error;
265 }
266 
267 void sys_set_thread_area(unsigned long addr)
268 {
269 	struct thread_info *ti = task_thread_info(current);
270 
271 	ti->tp_value = addr;
272 
273 	/* If some future MIPS implementation has this register in hardware,
274 	 * we will need to update it here (and in context switches).  */
275 }
276 
277 asmlinkage int _sys_sysmips(int cmd, long arg1, int arg2, int arg3)
278 {
279 	int	tmp;
280 
281 	switch(cmd) {
282 	case MIPS_ATOMIC_SET:
283 		printk(KERN_CRIT "How did I get here?\n");
284 		return -EINVAL;
285 
286 	case MIPS_FIXADE:
287 		tmp = current->thread.mflags & ~3;
288 		current->thread.mflags = tmp | (arg1 & 3);
289 		return 0;
290 
291 	case FLUSH_CACHE:
292 		__flush_cache_all();
293 		return 0;
294 	}
295 
296 	return -EINVAL;
297 }
298 
299 /*
300  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
301  *
302  * This is really horribly ugly.
303  */
304 asmlinkage int sys_ipc (uint call, int first, int second,
305 			unsigned long third, void __user *ptr, long fifth)
306 {
307 	int version, ret;
308 
309 	version = call >> 16; /* hack for backward compatibility */
310 	call &= 0xffff;
311 
312 	switch (call) {
313 	case SEMOP:
314 		return sys_semtimedop (first, (struct sembuf __user *)ptr,
315 		                       second, NULL);
316 	case SEMTIMEDOP:
317 		return sys_semtimedop (first, (struct sembuf __user *)ptr,
318 				       second,
319 				       (const struct timespec __user *)fifth);
320 	case SEMGET:
321 		return sys_semget (first, second, third);
322 	case SEMCTL: {
323 		union semun fourth;
324 		if (!ptr)
325 			return -EINVAL;
326 		if (get_user(fourth.__pad, (void __user *__user *) ptr))
327 			return -EFAULT;
328 		return sys_semctl (first, second, third, fourth);
329 	}
330 
331 	case MSGSND:
332 		return sys_msgsnd (first, (struct msgbuf __user *) ptr,
333 				   second, third);
334 	case MSGRCV:
335 		switch (version) {
336 		case 0: {
337 			struct ipc_kludge tmp;
338 			if (!ptr)
339 				return -EINVAL;
340 
341 			if (copy_from_user(&tmp,
342 					   (struct ipc_kludge __user *) ptr,
343 					   sizeof (tmp)))
344 				return -EFAULT;
345 			return sys_msgrcv (first, tmp.msgp, second,
346 					   tmp.msgtyp, third);
347 		}
348 		default:
349 			return sys_msgrcv (first,
350 					   (struct msgbuf __user *) ptr,
351 					   second, fifth, third);
352 		}
353 	case MSGGET:
354 		return sys_msgget ((key_t) first, second);
355 	case MSGCTL:
356 		return sys_msgctl (first, second,
357 				   (struct msqid_ds __user *) ptr);
358 
359 	case SHMAT:
360 		switch (version) {
361 		default: {
362 			ulong raddr;
363 			ret = do_shmat (first, (char __user *) ptr, second,
364 					&raddr);
365 			if (ret)
366 				return ret;
367 			return put_user (raddr, (ulong __user *) third);
368 		}
369 		case 1:	/* iBCS2 emulator entry point */
370 			if (!segment_eq(get_fs(), get_ds()))
371 				return -EINVAL;
372 			return do_shmat (first, (char __user *) ptr, second,
373 					 (ulong *) third);
374 		}
375 	case SHMDT:
376 		return sys_shmdt ((char __user *)ptr);
377 	case SHMGET:
378 		return sys_shmget (first, second, third);
379 	case SHMCTL:
380 		return sys_shmctl (first, second,
381 				   (struct shmid_ds __user *) ptr);
382 	default:
383 		return -ENOSYS;
384 	}
385 }
386 
387 /*
388  * No implemented yet ...
389  */
390 asmlinkage int sys_cachectl(char *addr, int nbytes, int op)
391 {
392 	return -ENOSYS;
393 }
394 
395 /*
396  * If we ever come here the user sp is bad.  Zap the process right away.
397  * Due to the bad stack signaling wouldn't work.
398  */
399 asmlinkage void bad_stack(void)
400 {
401 	do_exit(SIGSEGV);
402 }
403