arch/m32r/kernel/sys_m32r.c

   1 /*
   2  * linux/arch/m32r/kernel/sys_m32r.c
   3  *
   4  * This file contains various random system calls that
   5  * have a non-standard calling sequence on the Linux/M32R platform.
   6  *
   7  * Taken from i386 version.
   8  */
   9
  10 #include <linux/errno.h>
  11 #include <linux/sched.h>
  12 #include <linux/mm.h>
  13 #include <linux/fs.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
  24 #include <asm/uaccess.h>
  25 #include <asm/cachectl.h>
  26 #include <asm/cacheflush.h>
  27 #include <asm/ipc.h>
  28 #include <asm/syscall.h>
  29 #include <asm/unistd.h>
  30
  31 /*
  32  * sys_tas() - test-and-set
  33  */
  34 asmlinkage int sys_tas(int __user *addr)
  35 {
  36         int oldval;
  37
  38         if (!access_ok(VERIFY_WRITE, addr, sizeof (int)))
  39                 return -EFAULT;
  40
  41         /* atomic operation:
  42          *   oldval = *addr; *addr = 1;
  43          */
  44         __asm__ __volatile__ (
  45                 DCACHE_CLEAR("%0", "r4", "%1")
  46                 "       .fillinsn\n"
  47                 "1:\n"
  48                 "       lock    %0, @%1     ->  unlock  %2, @%1\n"
  49                 "2:\n"
  50                 /* NOTE:
  51                  *   The m32r processor can accept interrupts only
  52                  *   at the 32-bit instruction boundary.
  53                  *   So, in the above code, the "unlock" instruction
  54                  *   can be executed continuously after the "lock"
  55                  *   instruction execution without any interruptions.
  56                  */
  57                 ".section .fixup,\"ax\"\n"
  58                 "       .balign 4\n"
  59                 "3:     ldi     %0, #%3\n"
  60                 "       seth    r14, #high(2b)\n"
  61                 "       or3     r14, r14, #low(2b)\n"
  62                 "       jmp     r14\n"
  63                 ".previous\n"
  64                 ".section __ex_table,\"a\"\n"
  65                 "       .balign 4\n"
  66                 "       .long 1b,3b\n"
  67                 ".previous\n"
  68                 : "=&r" (oldval)
  69                 : "r" (addr), "r" (1), "i"(-EFAULT)
  70                 : "r14", "memory"
  71 #ifdef CONFIG_CHIP_M32700_TS1
  72                   , "r4"
  73 #endif /* CONFIG_CHIP_M32700_TS1 */
  74         );
  75
  76         return oldval;
  77 }
  78
  79 /*
  80  * sys_pipe() is the normal C calling standard for creating
  81  * a pipe. It's not the way Unix traditionally does this, though.
  82  */
  83 asmlinkage int
  84 sys_pipe(unsigned long r0, unsigned long r1, unsigned long r2,
  85         unsigned long r3, unsigned long r4, unsigned long r5,
  86         unsigned long r6, struct pt_regs regs)
  87 {
  88         int fd[2];
  89         int error;
  90
  91         error = do_pipe(fd);
  92         if (!error) {
  93                 if (copy_to_user((void __user *)r0, fd, 2*sizeof(int)))
  94                         error = -EFAULT;
  95         }
  96         return error;
  97 }
  98
  99 asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
 100         unsigned long prot, unsigned long flags,
 101         unsigned long fd, unsigned long pgoff)
 102 {
 103         int error = -EBADF;
 104         struct file *file = NULL;
 105
 106         flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
 107         if (!(flags & MAP_ANONYMOUS)) {
 108                 file = fget(fd);
 109                 if (!file)
 110                         goto out;
 111         }
 112
 113         down_write(&current->mm->mmap_sem);
 114         error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
 115         up_write(&current->mm->mmap_sem);
 116
 117         if (file)
 118                 fput(file);
 119 out:
 120         return error;
 121 }
 122
 123 /*
 124  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
 125  *
 126  * This is really horribly ugly.
 127  */
 128 asmlinkage int sys_ipc(uint call, int first, int second,
 129                        int third, void __user *ptr, long fifth)
 130 {
 131         int version, ret;
 132
 133         version = call >> 16; /* hack for backward compatibility */
 134         call &= 0xffff;
 135
 136         switch (call) {
 137         case SEMOP:
 138                 return sys_semtimedop(first, (struct sembuf __user *)ptr,
 139                                       second, NULL);
 140         case SEMTIMEDOP:
 141                 return sys_semtimedop(first, (struct sembuf __user *)ptr,
 142                                       second, (const struct timespec __user *)fifth);
 143         case SEMGET:
 144                 return sys_semget (first, second, third);
 145         case SEMCTL: {
 146                 union semun fourth;
 147                 if (!ptr)
 148                         return -EINVAL;
 149                 if (get_user(fourth.__pad, (void __user * __user *) ptr))
 150                         return -EFAULT;
 151                 return sys_semctl (first, second, third, fourth);
 152                 }
 153
 154         case MSGSND:
 155                 return sys_msgsnd (first, (struct msgbuf __user *) ptr,
 156                                    second, third);
 157         case MSGRCV:
 158                 switch (version) {
 159                 case 0: {
 160                         struct ipc_kludge tmp;
 161                         if (!ptr)
 162                                 return -EINVAL;
 163
 164                         if (copy_from_user(&tmp,
 165                                            (struct ipc_kludge __user *) ptr,
 166                                            sizeof (tmp)))
 167                                 return -EFAULT;
 168                         return sys_msgrcv (first, tmp.msgp, second,
 169                                            tmp.msgtyp, third);
 170                         }
 171                 default:
 172                         return sys_msgrcv (first,
 173                                            (struct msgbuf __user *) ptr,
 174                                            second, fifth, third);
 175                 }
 176         case MSGGET:
 177                 return sys_msgget ((key_t) first, second);
 178         case MSGCTL:
 179                 return sys_msgctl (first, second,
 180                                    (struct msqid_ds __user *) ptr);
 181         case SHMAT: {
 182                 ulong raddr;
 183
 184                 if (!access_ok(VERIFY_WRITE, (ulong __user *) third,
 185                                       sizeof(ulong)))
 186                         return -EFAULT;
 187                 ret = do_shmat (first, (char __user *) ptr, second, &raddr);
 188                 if (ret)
 189                         return ret;
 190                 return put_user (raddr, (ulong __user *) third);
 191                 }
 192         case SHMDT:
 193                 return sys_shmdt ((char __user *)ptr);
 194         case SHMGET:
 195                 return sys_shmget (first, second, third);
 196         case SHMCTL:
 197                 return sys_shmctl (first, second,
 198                                    (struct shmid_ds __user *) ptr);
 199         default:
 200                 return -ENOSYS;
 201         }
 202 }
 203
 204 asmlinkage int sys_uname(struct old_utsname __user * name)
 205 {
 206         int err;
 207         if (!name)
 208                 return -EFAULT;
 209         down_read(&uts_sem);
 210         err = copy_to_user(name, utsname(), sizeof (*name));
 211         up_read(&uts_sem);
 212         return err?-EFAULT:0;
 213 }
 214
 215 asmlinkage int sys_cacheflush(void *addr, int bytes, int cache)
 216 {
 217         /* This should flush more selectivly ...  */
 218         _flush_cache_all();
 219         return 0;
 220 }
 221
 222 asmlinkage int sys_cachectl(char *addr, int nbytes, int op)
 223 {
 224         /* Not implemented yet. */
 225         return -ENOSYS;
 226 }
 227
 228 /*
 229  * Do a system call from kernel instead of calling sys_execve so we
 230  * end up with proper pt_regs.
 231  */
 232 int kernel_execve(const char *filename, char *const argv[], char *const envp[])
 233 {
 234         register long __scno __asm__ ("r7") = __NR_execve;
 235         register long __arg3 __asm__ ("r2") = (long)(envp);
 236         register long __arg2 __asm__ ("r1") = (long)(argv);
 237         register long __res __asm__ ("r0") = (long)(filename);
 238         __asm__ __volatile__ (
 239                 "trap #" SYSCALL_VECTOR "|| nop"
 240                 : "=r" (__res)
 241                 : "r" (__scno), "0" (__res), "r" (__arg2),
 242                         "r" (__arg3)
 243                 : "memory");
 244         return __res;
 245 }