xref: /openbmc/linux/arch/sh/kernel/sys_sh.c (revision f15cbe6f1a4b4d9df59142fc8e4abb973302cf44)
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 #include <linux/errno.h>
11 #include <linux/sched.h>
12 #include <linux/mm.h>
13 #include <linux/smp.h>
14 #include <linux/sem.h>
15 #include <linux/msg.h>
16 #include <linux/shm.h>
17 #include <linux/stat.h>
18 #include <linux/syscalls.h>
19 #include <linux/mman.h>
20 #include <linux/file.h>
21 #include <linux/utsname.h>
22 #include <linux/module.h>
23 #include <linux/fs.h>
24 #include <linux/ipc.h>
25 #include <asm/cacheflush.h>
26 #include <asm/uaccess.h>
27 #include <asm/unistd.h>
28 
29 unsigned long shm_align_mask = PAGE_SIZE - 1;	/* Sane caches */
30 EXPORT_SYMBOL(shm_align_mask);
31 
32 #ifdef CONFIG_MMU
33 /*
34  * To avoid cache aliases, we map the shared page with same color.
35  */
36 #define COLOUR_ALIGN(addr, pgoff)				\
37 	((((addr) + shm_align_mask) & ~shm_align_mask) +	\
38 	 (((pgoff) << PAGE_SHIFT) & shm_align_mask))
39 
40 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
41 	unsigned long len, unsigned long pgoff, unsigned long flags)
42 {
43 	struct mm_struct *mm = current->mm;
44 	struct vm_area_struct *vma;
45 	unsigned long start_addr;
46 	int do_colour_align;
47 
48 	if (flags & MAP_FIXED) {
49 		/* We do not accept a shared mapping if it would violate
50 		 * cache aliasing constraints.
51 		 */
52 		if ((flags & MAP_SHARED) && (addr & shm_align_mask))
53 			return -EINVAL;
54 		return addr;
55 	}
56 
57 	if (unlikely(len > TASK_SIZE))
58 		return -ENOMEM;
59 
60 	do_colour_align = 0;
61 	if (filp || (flags & MAP_SHARED))
62 		do_colour_align = 1;
63 
64 	if (addr) {
65 		if (do_colour_align)
66 			addr = COLOUR_ALIGN(addr, pgoff);
67 		else
68 			addr = PAGE_ALIGN(addr);
69 
70 		vma = find_vma(mm, addr);
71 		if (TASK_SIZE - len >= addr &&
72 		    (!vma || addr + len <= vma->vm_start))
73 			return addr;
74 	}
75 
76 	if (len > mm->cached_hole_size) {
77 		start_addr = addr = mm->free_area_cache;
78 	} else {
79 	        mm->cached_hole_size = 0;
80 		start_addr = addr = TASK_UNMAPPED_BASE;
81 	}
82 
83 full_search:
84 	if (do_colour_align)
85 		addr = COLOUR_ALIGN(addr, pgoff);
86 	else
87 		addr = PAGE_ALIGN(mm->free_area_cache);
88 
89 	for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
90 		/* At this point:  (!vma || addr < vma->vm_end). */
91 		if (unlikely(TASK_SIZE - len < addr)) {
92 			/*
93 			 * Start a new search - just in case we missed
94 			 * some holes.
95 			 */
96 			if (start_addr != TASK_UNMAPPED_BASE) {
97 				start_addr = addr = TASK_UNMAPPED_BASE;
98 				mm->cached_hole_size = 0;
99 				goto full_search;
100 			}
101 			return -ENOMEM;
102 		}
103 		if (likely(!vma || addr + len <= vma->vm_start)) {
104 			/*
105 			 * Remember the place where we stopped the search:
106 			 */
107 			mm->free_area_cache = addr + len;
108 			return addr;
109 		}
110 		if (addr + mm->cached_hole_size < vma->vm_start)
111 		        mm->cached_hole_size = vma->vm_start - addr;
112 
113 		addr = vma->vm_end;
114 		if (do_colour_align)
115 			addr = COLOUR_ALIGN(addr, pgoff);
116 	}
117 }
118 #endif /* CONFIG_MMU */
119 
120 static inline long
121 do_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
122 	 unsigned long flags, int fd, unsigned long pgoff)
123 {
124 	int error = -EBADF;
125 	struct file *file = NULL;
126 
127 	flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
128 	if (!(flags & MAP_ANONYMOUS)) {
129 		file = fget(fd);
130 		if (!file)
131 			goto out;
132 	}
133 
134 	down_write(&current->mm->mmap_sem);
135 	error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
136 	up_write(&current->mm->mmap_sem);
137 
138 	if (file)
139 		fput(file);
140 out:
141 	return error;
142 }
143 
144 asmlinkage int old_mmap(unsigned long addr, unsigned long len,
145 	unsigned long prot, unsigned long flags,
146 	int fd, unsigned long off)
147 {
148 	if (off & ~PAGE_MASK)
149 		return -EINVAL;
150 	return do_mmap2(addr, len, prot, flags, fd, off>>PAGE_SHIFT);
151 }
152 
153 asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
154 	unsigned long prot, unsigned long flags,
155 	unsigned long fd, unsigned long pgoff)
156 {
157 	return do_mmap2(addr, len, prot, flags, fd, pgoff);
158 }
159 
160 /*
161  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
162  *
163  * This is really horribly ugly.
164  */
165 asmlinkage int sys_ipc(uint call, int first, int second,
166 		       int third, void __user *ptr, long fifth)
167 {
168 	int version, ret;
169 
170 	version = call >> 16; /* hack for backward compatibility */
171 	call &= 0xffff;
172 
173 	if (call <= SEMCTL)
174 		switch (call) {
175 		case SEMOP:
176 			return sys_semtimedop(first,
177 					      (struct sembuf __user *)ptr,
178 					      second, NULL);
179 		case SEMTIMEDOP:
180 			return sys_semtimedop(first,
181 				(struct sembuf __user *)ptr, second,
182 			        (const struct timespec __user *)fifth);
183 		case SEMGET:
184 			return sys_semget (first, second, third);
185 		case SEMCTL: {
186 			union semun fourth;
187 			if (!ptr)
188 				return -EINVAL;
189 			if (get_user(fourth.__pad, (void * __user *) ptr))
190 				return -EFAULT;
191 			return sys_semctl (first, second, third, fourth);
192 			}
193 		default:
194 			return -EINVAL;
195 		}
196 
197 	if (call <= MSGCTL)
198 		switch (call) {
199 		case MSGSND:
200 			return sys_msgsnd (first, (struct msgbuf __user *) ptr,
201 					  second, third);
202 		case MSGRCV:
203 			switch (version) {
204 			case 0:
205 			{
206 				struct ipc_kludge tmp;
207 
208 				if (!ptr)
209 					return -EINVAL;
210 
211 				if (copy_from_user(&tmp,
212 					(struct ipc_kludge __user *) ptr,
213 						   sizeof (tmp)))
214 					return -EFAULT;
215 
216 				return sys_msgrcv (first, tmp.msgp, second,
217 						   tmp.msgtyp, third);
218 			}
219 			default:
220 				return sys_msgrcv (first,
221 						   (struct msgbuf __user *) ptr,
222 						   second, fifth, third);
223 			}
224 		case MSGGET:
225 			return sys_msgget ((key_t) first, second);
226 		case MSGCTL:
227 			return sys_msgctl (first, second,
228 					   (struct msqid_ds __user *) ptr);
229 		default:
230 			return -EINVAL;
231 		}
232 	if (call <= SHMCTL)
233 		switch (call) {
234 		case SHMAT:
235 			switch (version) {
236 			default: {
237 				ulong raddr;
238 				ret = do_shmat (first, (char __user *) ptr,
239 						 second, &raddr);
240 				if (ret)
241 					return ret;
242 				return put_user (raddr, (ulong __user *) third);
243 			}
244 			case 1:	/* iBCS2 emulator entry point */
245 				if (!segment_eq(get_fs(), get_ds()))
246 					return -EINVAL;
247 				return do_shmat (first, (char __user *) ptr,
248 						  second, (ulong *) third);
249 			}
250 		case SHMDT:
251 			return sys_shmdt ((char __user *)ptr);
252 		case SHMGET:
253 			return sys_shmget (first, second, third);
254 		case SHMCTL:
255 			return sys_shmctl (first, second,
256 					   (struct shmid_ds __user *) ptr);
257 		default:
258 			return -EINVAL;
259 		}
260 
261 	return -EINVAL;
262 }
263 
264 asmlinkage int sys_uname(struct old_utsname * name)
265 {
266 	int err;
267 	if (!name)
268 		return -EFAULT;
269 	down_read(&uts_sem);
270 	err = copy_to_user(name, utsname(), sizeof (*name));
271 	up_read(&uts_sem);
272 	return err?-EFAULT:0;
273 }
274