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 #include <linux/ipc.h>
  24
  25 #include <asm/uaccess.h>
  26 #include <asm/cachectl.h>
  27 #include <asm/cacheflush.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_ipc() is the de-multiplexer for the SysV IPC calls..
  81  *
  82  * This is really horribly ugly.
  83  */
  84 asmlinkage int sys_ipc(uint call, int first, int second,
  85                        int third, void __user *ptr, long fifth)
  86 {
  87         int version, ret;
  88
  89         version = call >> 16; /* hack for backward compatibility */
  90         call &= 0xffff;
  91
  92         switch (call) {
  93         case SEMOP:
  94                 return sys_semtimedop(first, (struct sembuf __user *)ptr,
  95                                       second, NULL);
  96         case SEMTIMEDOP:
  97                 return sys_semtimedop(first, (struct sembuf __user *)ptr,
  98                                       second, (const struct timespec __user *)fifth);
  99         case SEMGET:
 100                 return sys_semget (first, second, third);
 101         case SEMCTL: {
 102                 union semun fourth;
 103                 if (!ptr)
 104                         return -EINVAL;
 105                 if (get_user(fourth.__pad, (void __user * __user *) ptr))
 106                         return -EFAULT;
 107                 return sys_semctl (first, second, third, fourth);
 108                 }
 109
 110         case MSGSND:
 111                 return sys_msgsnd (first, (struct msgbuf __user *) ptr,
 112                                    second, third);
 113         case MSGRCV:
 114                 switch (version) {
 115                 case 0: {
 116                         struct ipc_kludge tmp;
 117                         if (!ptr)
 118                                 return -EINVAL;
 119
 120                         if (copy_from_user(&tmp,
 121                                            (struct ipc_kludge __user *) ptr,
 122                                            sizeof (tmp)))
 123                                 return -EFAULT;
 124                         return sys_msgrcv (first, tmp.msgp, second,
 125                                            tmp.msgtyp, third);
 126                         }
 127                 default:
 128                         return sys_msgrcv (first,
 129                                            (struct msgbuf __user *) ptr,
 130                                            second, fifth, third);
 131                 }
 132         case MSGGET:
 133                 return sys_msgget ((key_t) first, second);
 134         case MSGCTL:
 135                 return sys_msgctl (first, second,
 136                                    (struct msqid_ds __user *) ptr);
 137         case SHMAT: {
 138                 ulong raddr;
 139
 140                 if (!access_ok(VERIFY_WRITE, (ulong __user *) third,
 141                                       sizeof(ulong)))
 142                         return -EFAULT;
 143                 ret = do_shmat (first, (char __user *) ptr, second, &raddr);
 144                 if (ret)
 145                         return ret;
 146                 return put_user (raddr, (ulong __user *) third);
 147                 }
 148         case SHMDT:
 149                 return sys_shmdt ((char __user *)ptr);
 150         case SHMGET:
 151                 return sys_shmget (first, second, third);
 152         case SHMCTL:
 153                 return sys_shmctl (first, second,
 154                                    (struct shmid_ds __user *) ptr);
 155         default:
 156                 return -ENOSYS;
 157         }
 158 }
 159
 160 asmlinkage int sys_uname(struct old_utsname __user * name)
 161 {
 162         int err;
 163         if (!name)
 164                 return -EFAULT;
 165         down_read(&uts_sem);
 166         err = copy_to_user(name, utsname(), sizeof (*name));
 167         up_read(&uts_sem);
 168         return err?-EFAULT:0;
 169 }
 170
 171 asmlinkage int sys_cacheflush(void *addr, int bytes, int cache)
 172 {
 173         /* This should flush more selectively ...  */
 174         _flush_cache_all();
 175         return 0;
 176 }
 177
 178 asmlinkage int sys_cachectl(char *addr, int nbytes, int op)
 179 {
 180         /* Not implemented yet. */
 181         return -ENOSYS;
 182 }
 183
 184 /*
 185  * Do a system call from kernel instead of calling sys_execve so we
 186  * end up with proper pt_regs.
 187  */
 188 int kernel_execve(const char *filename, char *const argv[], char *const envp[])
 189 {
 190         register long __scno __asm__ ("r7") = __NR_execve;
 191         register long __arg3 __asm__ ("r2") = (long)(envp);
 192         register long __arg2 __asm__ ("r1") = (long)(argv);
 193         register long __res __asm__ ("r0") = (long)(filename);
 194         __asm__ __volatile__ (
 195                 "trap #" SYSCALL_VECTOR "|| nop"
 196                 : "=r" (__res)
 197                 : "r" (__scno), "0" (__res), "r" (__arg2),
 198                         "r" (__arg3)
 199                 : "memory");
 200         return __res;
 201 }