xref: /openbmc/linux/arch/sh/kernel/sys_sh.c (revision 96de0e252cedffad61b3cb5e05662c591898e69a)
1 /*
2  * linux/arch/sh/kernel/sys_sh.c
3  *
4  * This file contains various random system calls that
5  * have a non-standard calling sequence on the Linux/SuperH
6  * platform.
7  *
8  * Taken from i386 version.
9  */
10 
11 #include <linux/errno.h>
12 #include <linux/sched.h>
13 #include <linux/mm.h>
14 #include <linux/smp.h>
15 #include <linux/sem.h>
16 #include <linux/msg.h>
17 #include <linux/shm.h>
18 #include <linux/stat.h>
19 #include <linux/syscalls.h>
20 #include <linux/mman.h>
21 #include <linux/file.h>
22 #include <linux/utsname.h>
23 #include <linux/module.h>
24 #include <linux/fs.h>
25 #include <linux/ipc.h>
26 #include <asm/cacheflush.h>
27 #include <asm/uaccess.h>
28 #include <asm/unistd.h>
29 
30 /*
31  * sys_pipe() is the normal C calling standard for creating
32  * a pipe. It's not the way Unix traditionally does this, though.
33  */
34 asmlinkage int sys_pipe(unsigned long r4, unsigned long r5,
35 	unsigned long r6, unsigned long r7,
36 	struct pt_regs __regs)
37 {
38 	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
39 	int fd[2];
40 	int error;
41 
42 	error = do_pipe(fd);
43 	if (!error) {
44 		regs->regs[1] = fd[1];
45 		return fd[0];
46 	}
47 	return error;
48 }
49 
50 unsigned long shm_align_mask = PAGE_SIZE - 1;	/* Sane caches */
51 
52 EXPORT_SYMBOL(shm_align_mask);
53 
54 #ifdef CONFIG_MMU
55 /*
56  * To avoid cache aliases, we map the shared page with same color.
57  */
58 #define COLOUR_ALIGN(addr, pgoff)				\
59 	((((addr) + shm_align_mask) & ~shm_align_mask) +	\
60 	 (((pgoff) << PAGE_SHIFT) & shm_align_mask))
61 
62 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
63 	unsigned long len, unsigned long pgoff, unsigned long flags)
64 {
65 	struct mm_struct *mm = current->mm;
66 	struct vm_area_struct *vma;
67 	unsigned long start_addr;
68 	int do_colour_align;
69 
70 	if (flags & MAP_FIXED) {
71 		/* We do not accept a shared mapping if it would violate
72 		 * cache aliasing constraints.
73 		 */
74 		if ((flags & MAP_SHARED) && (addr & shm_align_mask))
75 			return -EINVAL;
76 		return addr;
77 	}
78 
79 	if (unlikely(len > TASK_SIZE))
80 		return -ENOMEM;
81 
82 	do_colour_align = 0;
83 	if (filp || (flags & MAP_SHARED))
84 		do_colour_align = 1;
85 
86 	if (addr) {
87 		if (do_colour_align)
88 			addr = COLOUR_ALIGN(addr, pgoff);
89 		else
90 			addr = PAGE_ALIGN(addr);
91 
92 		vma = find_vma(mm, addr);
93 		if (TASK_SIZE - len >= addr &&
94 		    (!vma || addr + len <= vma->vm_start))
95 			return addr;
96 	}
97 
98 	if (len > mm->cached_hole_size) {
99 		start_addr = addr = mm->free_area_cache;
100 	} else {
101 	        mm->cached_hole_size = 0;
102 		start_addr = addr = TASK_UNMAPPED_BASE;
103 	}
104 
105 full_search:
106 	if (do_colour_align)
107 		addr = COLOUR_ALIGN(addr, pgoff);
108 	else
109 		addr = PAGE_ALIGN(mm->free_area_cache);
110 
111 	for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
112 		/* At this point:  (!vma || addr < vma->vm_end). */
113 		if (unlikely(TASK_SIZE - len < addr)) {
114 			/*
115 			 * Start a new search - just in case we missed
116 			 * some holes.
117 			 */
118 			if (start_addr != TASK_UNMAPPED_BASE) {
119 				start_addr = addr = TASK_UNMAPPED_BASE;
120 				mm->cached_hole_size = 0;
121 				goto full_search;
122 			}
123 			return -ENOMEM;
124 		}
125 		if (likely(!vma || addr + len <= vma->vm_start)) {
126 			/*
127 			 * Remember the place where we stopped the search:
128 			 */
129 			mm->free_area_cache = addr + len;
130 			return addr;
131 		}
132 		if (addr + mm->cached_hole_size < vma->vm_start)
133 		        mm->cached_hole_size = vma->vm_start - addr;
134 
135 		addr = vma->vm_end;
136 		if (do_colour_align)
137 			addr = COLOUR_ALIGN(addr, pgoff);
138 	}
139 }
140 #endif /* CONFIG_MMU */
141 
142 static inline long
143 do_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
144 	 unsigned long flags, int fd, unsigned long pgoff)
145 {
146 	int error = -EBADF;
147 	struct file *file = NULL;
148 
149 	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
150 	if (!(flags & MAP_ANONYMOUS)) {
151 		file = fget(fd);
152 		if (!file)
153 			goto out;
154 	}
155 
156 	down_write(&current->mm->mmap_sem);
157 	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
158 	up_write(&current->mm->mmap_sem);
159 
160 	if (file)
161 		fput(file);
162 out:
163 	return error;
164 }
165 
166 asmlinkage int old_mmap(unsigned long addr, unsigned long len,
167 	unsigned long prot, unsigned long flags,
168 	int fd, unsigned long off)
169 {
170 	if (off & ~PAGE_MASK)
171 		return -EINVAL;
172 	return do_mmap2(addr, len, prot, flags, fd, off>>PAGE_SHIFT);
173 }
174 
175 asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
176 	unsigned long prot, unsigned long flags,
177 	unsigned long fd, unsigned long pgoff)
178 {
179 	return do_mmap2(addr, len, prot, flags, fd, pgoff);
180 }
181 
182 /*
183  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
184  *
185  * This is really horribly ugly.
186  */
187 asmlinkage int sys_ipc(uint call, int first, int second,
188 		       int third, void __user *ptr, long fifth)
189 {
190 	int version, ret;
191 
192 	version = call >> 16; /* hack for backward compatibility */
193 	call &= 0xffff;
194 
195 	if (call <= SEMCTL)
196 		switch (call) {
197 		case SEMOP:
198 			return sys_semtimedop(first, (struct sembuf __user *)ptr,
199 					      second, NULL);
200 		case SEMTIMEDOP:
201 			return sys_semtimedop(first, (struct sembuf __user *)ptr,
202 					      second,
203 					      (const struct timespec __user *)fifth);
204 		case SEMGET:
205 			return sys_semget (first, second, third);
206 		case SEMCTL: {
207 			union semun fourth;
208 			if (!ptr)
209 				return -EINVAL;
210 			if (get_user(fourth.__pad, (void * __user *) ptr))
211 				return -EFAULT;
212 			return sys_semctl (first, second, third, fourth);
213 			}
214 		default:
215 			return -EINVAL;
216 		}
217 
218 	if (call <= MSGCTL)
219 		switch (call) {
220 		case MSGSND:
221 			return sys_msgsnd (first, (struct msgbuf __user *) ptr,
222 					  second, third);
223 		case MSGRCV:
224 			switch (version) {
225 			case 0: {
226 				struct ipc_kludge tmp;
227 				if (!ptr)
228 					return -EINVAL;
229 
230 				if (copy_from_user(&tmp,
231 						   (struct ipc_kludge __user *) ptr,
232 						   sizeof (tmp)))
233 					return -EFAULT;
234 				return sys_msgrcv (first, tmp.msgp, second,
235 						   tmp.msgtyp, third);
236 				}
237 			default:
238 				return sys_msgrcv (first,
239 						   (struct msgbuf __user *) ptr,
240 						   second, fifth, third);
241 			}
242 		case MSGGET:
243 			return sys_msgget ((key_t) first, second);
244 		case MSGCTL:
245 			return sys_msgctl (first, second,
246 					   (struct msqid_ds __user *) ptr);
247 		default:
248 			return -EINVAL;
249 		}
250 	if (call <= SHMCTL)
251 		switch (call) {
252 		case SHMAT:
253 			switch (version) {
254 			default: {
255 				ulong raddr;
256 				ret = do_shmat (first, (char __user *) ptr,
257 						 second, &raddr);
258 				if (ret)
259 					return ret;
260 				return put_user (raddr, (ulong __user *) third);
261 			}
262 			case 1:	/* iBCS2 emulator entry point */
263 				if (!segment_eq(get_fs(), get_ds()))
264 					return -EINVAL;
265 				return do_shmat (first, (char __user *) ptr,
266 						  second, (ulong *) third);
267 			}
268 		case SHMDT:
269 			return sys_shmdt ((char __user *)ptr);
270 		case SHMGET:
271 			return sys_shmget (first, second, third);
272 		case SHMCTL:
273 			return sys_shmctl (first, second,
274 					   (struct shmid_ds __user *) ptr);
275 		default:
276 			return -EINVAL;
277 		}
278 
279 	return -EINVAL;
280 }
281 
282 asmlinkage int sys_uname(struct old_utsname * name)
283 {
284 	int err;
285 	if (!name)
286 		return -EFAULT;
287 	down_read(&uts_sem);
288 	err = copy_to_user(name, utsname(), sizeof (*name));
289 	up_read(&uts_sem);
290 	return err?-EFAULT:0;
291 }
292 
293 asmlinkage ssize_t sys_pread_wrapper(unsigned int fd, char * buf,
294 			     size_t count, long dummy, loff_t pos)
295 {
296 	return sys_pread64(fd, buf, count, pos);
297 }
298 
299 asmlinkage ssize_t sys_pwrite_wrapper(unsigned int fd, const char * buf,
300 			      size_t count, long dummy, loff_t pos)
301 {
302 	return sys_pwrite64(fd, buf, count, pos);
303 }
304 
305 asmlinkage int sys_fadvise64_64_wrapper(int fd, u32 offset0, u32 offset1,
306 				u32 len0, u32 len1, int advice)
307 {
308 #ifdef  __LITTLE_ENDIAN__
309 	return sys_fadvise64_64(fd, (u64)offset1 << 32 | offset0,
310 				(u64)len1 << 32 | len0,	advice);
311 #else
312 	return sys_fadvise64_64(fd, (u64)offset0 << 32 | offset1,
313 				(u64)len0 << 32 | len1,	advice);
314 #endif
315 }
316 
317 #if defined(CONFIG_CPU_SH2) || defined(CONFIG_CPU_SH2A)
318 #define SYSCALL_ARG3	"trapa #0x23"
319 #else
320 #define SYSCALL_ARG3	"trapa #0x13"
321 #endif
322 
323 /*
324  * Do a system call from kernel instead of calling sys_execve so we
325  * end up with proper pt_regs.
326  */
327 int kernel_execve(const char *filename, char *const argv[], char *const envp[])
328 {
329 	register long __sc0 __asm__ ("r3") = __NR_execve;
330 	register long __sc4 __asm__ ("r4") = (long) filename;
331 	register long __sc5 __asm__ ("r5") = (long) argv;
332 	register long __sc6 __asm__ ("r6") = (long) envp;
333 	__asm__ __volatile__ (SYSCALL_ARG3 : "=z" (__sc0)
334 			: "0" (__sc0), "r" (__sc4), "r" (__sc5), "r" (__sc6)
335 			: "memory");
336 	return __sc0;
337 }
338