Merge commit 'v2.6.27-rc6' into core/rcu
[linux-2.6] / arch / sh / kernel / sys_sh.c
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 <= SEMTIMEDOP)
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 }