xref: /openbmc/linux/arch/sh/kernel/sys_sh.c (revision 64c70b1c)
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 <asm/cacheflush.h>
25 #include <asm/uaccess.h>
26 #include <asm/ipc.h>
27 #include <asm/unistd.h>
28 
29 /*
30  * sys_pipe() is the normal C calling standard for creating
31  * a pipe. It's not the way Unix traditionally does this, though.
32  */
33 asmlinkage int sys_pipe(unsigned long r4, unsigned long r5,
34 	unsigned long r6, unsigned long r7,
35 	struct pt_regs __regs)
36 {
37 	struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
38 	int fd[2];
39 	int error;
40 
41 	error = do_pipe(fd);
42 	if (!error) {
43 		regs->regs[1] = fd[1];
44 		return fd[0];
45 	}
46 	return error;
47 }
48 
49 unsigned long shm_align_mask = PAGE_SIZE - 1;	/* Sane caches */
50 
51 EXPORT_SYMBOL(shm_align_mask);
52 
53 #ifdef CONFIG_MMU
54 /*
55  * To avoid cache aliases, we map the shared page with same color.
56  */
57 #define COLOUR_ALIGN(addr, pgoff)				\
58 	((((addr) + shm_align_mask) & ~shm_align_mask) +	\
59 	 (((pgoff) << PAGE_SHIFT) & shm_align_mask))
60 
61 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
62 	unsigned long len, unsigned long pgoff, unsigned long flags)
63 {
64 	struct mm_struct *mm = current->mm;
65 	struct vm_area_struct *vma;
66 	unsigned long start_addr;
67 	int do_colour_align;
68 
69 	if (flags & MAP_FIXED) {
70 		/* We do not accept a shared mapping if it would violate
71 		 * cache aliasing constraints.
72 		 */
73 		if ((flags & MAP_SHARED) && (addr & shm_align_mask))
74 			return -EINVAL;
75 		return addr;
76 	}
77 
78 	if (unlikely(len > TASK_SIZE))
79 		return -ENOMEM;
80 
81 	do_colour_align = 0;
82 	if (filp || (flags & MAP_SHARED))
83 		do_colour_align = 1;
84 
85 	if (addr) {
86 		if (do_colour_align)
87 			addr = COLOUR_ALIGN(addr, pgoff);
88 		else
89 			addr = PAGE_ALIGN(addr);
90 
91 		vma = find_vma(mm, addr);
92 		if (TASK_SIZE - len >= addr &&
93 		    (!vma || addr + len <= vma->vm_start))
94 			return addr;
95 	}
96 
97 	if (len > mm->cached_hole_size) {
98 		start_addr = addr = mm->free_area_cache;
99 	} else {
100 	        mm->cached_hole_size = 0;
101 		start_addr = addr = TASK_UNMAPPED_BASE;
102 	}
103 
104 full_search:
105 	if (do_colour_align)
106 		addr = COLOUR_ALIGN(addr, pgoff);
107 	else
108 		addr = PAGE_ALIGN(mm->free_area_cache);
109 
110 	for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
111 		/* At this point:  (!vma || addr < vma->vm_end). */
112 		if (unlikely(TASK_SIZE - len < addr)) {
113 			/*
114 			 * Start a new search - just in case we missed
115 			 * some holes.
116 			 */
117 			if (start_addr != TASK_UNMAPPED_BASE) {
118 				start_addr = addr = TASK_UNMAPPED_BASE;
119 				mm->cached_hole_size = 0;
120 				goto full_search;
121 			}
122 			return -ENOMEM;
123 		}
124 		if (likely(!vma || addr + len <= vma->vm_start)) {
125 			/*
126 			 * Remember the place where we stopped the search:
127 			 */
128 			mm->free_area_cache = addr + len;
129 			return addr;
130 		}
131 		if (addr + mm->cached_hole_size < vma->vm_start)
132 		        mm->cached_hole_size = vma->vm_start - addr;
133 
134 		addr = vma->vm_end;
135 		if (do_colour_align)
136 			addr = COLOUR_ALIGN(addr, pgoff);
137 	}
138 }
139 #endif /* CONFIG_MMU */
140 
141 static inline long
142 do_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
143 	 unsigned long flags, int fd, unsigned long pgoff)
144 {
145 	int error = -EBADF;
146 	struct file *file = NULL;
147 
148 	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
149 	if (!(flags & MAP_ANONYMOUS)) {
150 		file = fget(fd);
151 		if (!file)
152 			goto out;
153 	}
154 
155 	down_write(&current->mm->mmap_sem);
156 	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
157 	up_write(&current->mm->mmap_sem);
158 
159 	if (file)
160 		fput(file);
161 out:
162 	return error;
163 }
164 
165 asmlinkage int old_mmap(unsigned long addr, unsigned long len,
166 	unsigned long prot, unsigned long flags,
167 	int fd, unsigned long off)
168 {
169 	if (off & ~PAGE_MASK)
170 		return -EINVAL;
171 	return do_mmap2(addr, len, prot, flags, fd, off>>PAGE_SHIFT);
172 }
173 
174 asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
175 	unsigned long prot, unsigned long flags,
176 	unsigned long fd, unsigned long pgoff)
177 {
178 	return do_mmap2(addr, len, prot, flags, fd, pgoff);
179 }
180 
181 /*
182  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
183  *
184  * This is really horribly ugly.
185  */
186 asmlinkage int sys_ipc(uint call, int first, int second,
187 		       int third, void __user *ptr, long fifth)
188 {
189 	int version, ret;
190 
191 	version = call >> 16; /* hack for backward compatibility */
192 	call &= 0xffff;
193 
194 	if (call <= SEMCTL)
195 		switch (call) {
196 		case SEMOP:
197 			return sys_semtimedop(first, (struct sembuf __user *)ptr,
198 					      second, NULL);
199 		case SEMTIMEDOP:
200 			return sys_semtimedop(first, (struct sembuf __user *)ptr,
201 					      second,
202 					      (const struct timespec __user *)fifth);
203 		case SEMGET:
204 			return sys_semget (first, second, third);
205 		case SEMCTL: {
206 			union semun fourth;
207 			if (!ptr)
208 				return -EINVAL;
209 			if (get_user(fourth.__pad, (void * __user *) ptr))
210 				return -EFAULT;
211 			return sys_semctl (first, second, third, fourth);
212 			}
213 		default:
214 			return -EINVAL;
215 		}
216 
217 	if (call <= MSGCTL)
218 		switch (call) {
219 		case MSGSND:
220 			return sys_msgsnd (first, (struct msgbuf __user *) ptr,
221 					  second, third);
222 		case MSGRCV:
223 			switch (version) {
224 			case 0: {
225 				struct ipc_kludge tmp;
226 				if (!ptr)
227 					return -EINVAL;
228 
229 				if (copy_from_user(&tmp,
230 						   (struct ipc_kludge __user *) ptr,
231 						   sizeof (tmp)))
232 					return -EFAULT;
233 				return sys_msgrcv (first, tmp.msgp, second,
234 						   tmp.msgtyp, third);
235 				}
236 			default:
237 				return sys_msgrcv (first,
238 						   (struct msgbuf __user *) ptr,
239 						   second, fifth, third);
240 			}
241 		case MSGGET:
242 			return sys_msgget ((key_t) first, second);
243 		case MSGCTL:
244 			return sys_msgctl (first, second,
245 					   (struct msqid_ds __user *) ptr);
246 		default:
247 			return -EINVAL;
248 		}
249 	if (call <= SHMCTL)
250 		switch (call) {
251 		case SHMAT:
252 			switch (version) {
253 			default: {
254 				ulong raddr;
255 				ret = do_shmat (first, (char __user *) ptr,
256 						 second, &raddr);
257 				if (ret)
258 					return ret;
259 				return put_user (raddr, (ulong __user *) third);
260 			}
261 			case 1:	/* iBCS2 emulator entry point */
262 				if (!segment_eq(get_fs(), get_ds()))
263 					return -EINVAL;
264 				return do_shmat (first, (char __user *) ptr,
265 						  second, (ulong *) third);
266 			}
267 		case SHMDT:
268 			return sys_shmdt ((char __user *)ptr);
269 		case SHMGET:
270 			return sys_shmget (first, second, third);
271 		case SHMCTL:
272 			return sys_shmctl (first, second,
273 					   (struct shmid_ds __user *) ptr);
274 		default:
275 			return -EINVAL;
276 		}
277 
278 	return -EINVAL;
279 }
280 
281 asmlinkage int sys_uname(struct old_utsname * name)
282 {
283 	int err;
284 	if (!name)
285 		return -EFAULT;
286 	down_read(&uts_sem);
287 	err = copy_to_user(name, utsname(), sizeof (*name));
288 	up_read(&uts_sem);
289 	return err?-EFAULT:0;
290 }
291 
292 asmlinkage ssize_t sys_pread_wrapper(unsigned int fd, char * buf,
293 			     size_t count, long dummy, loff_t pos)
294 {
295 	return sys_pread64(fd, buf, count, pos);
296 }
297 
298 asmlinkage ssize_t sys_pwrite_wrapper(unsigned int fd, const char * buf,
299 			      size_t count, long dummy, loff_t pos)
300 {
301 	return sys_pwrite64(fd, buf, count, pos);
302 }
303 
304 asmlinkage int sys_fadvise64_64_wrapper(int fd, u32 offset0, u32 offset1,
305 				u32 len0, u32 len1, int advice)
306 {
307 #ifdef  __LITTLE_ENDIAN__
308 	return sys_fadvise64_64(fd, (u64)offset1 << 32 | offset0,
309 				(u64)len1 << 32 | len0,	advice);
310 #else
311 	return sys_fadvise64_64(fd, (u64)offset0 << 32 | offset1,
312 				(u64)len0 << 32 | len1,	advice);
313 #endif
314 }
315 
316 #if defined(CONFIG_CPU_SH2) || defined(CONFIG_CPU_SH2A)
317 #define SYSCALL_ARG3	"trapa #0x23"
318 #else
319 #define SYSCALL_ARG3	"trapa #0x13"
320 #endif
321 
322 /*
323  * Do a system call from kernel instead of calling sys_execve so we
324  * end up with proper pt_regs.
325  */
326 int kernel_execve(const char *filename, char *const argv[], char *const envp[])
327 {
328 	register long __sc0 __asm__ ("r3") = __NR_execve;
329 	register long __sc4 __asm__ ("r4") = (long) filename;
330 	register long __sc5 __asm__ ("r5") = (long) argv;
331 	register long __sc6 __asm__ ("r6") = (long) envp;
332 	__asm__ __volatile__ (SYSCALL_ARG3 : "=z" (__sc0)
333 			: "0" (__sc0), "r" (__sc4), "r" (__sc5), "r" (__sc6)
334 			: "memory");
335 	return __sc0;
336 }
337