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 asmlinkage long sys_mmap2(unsigned long addr, unsigned long len,
  80         unsigned long prot, unsigned long flags,
  81         unsigned long fd, unsigned long pgoff)
  82 {
  83         int error = -EBADF;
  84         struct file *file = NULL;
  85
  86         flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
  87         if (!(flags & MAP_ANONYMOUS)) {
  88                 file = fget(fd);
  89                 if (!file)
  90                         goto out;
  91         }
  92
  93         down_write(&current->mm->mmap_sem);
  94         error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
  95         up_write(&current->mm->mmap_sem);
  96
  97         if (file)
  98                 fput(file);
  99 out:
 100         return error;
 101 }
 102
 103 /*
 104  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
 105  *
 106  * This is really horribly ugly.
 107  */
 108 asmlinkage int sys_ipc(uint call, int first, int second,
 109                        int third, void __user *ptr, long fifth)
 110 {
 111         int version, ret;
 112
 113         version = call >> 16; /* hack for backward compatibility */
 114         call &= 0xffff;
 115
 116         switch (call) {
 117         case SEMOP:
 118                 return sys_semtimedop(first, (struct sembuf __user *)ptr,
 119                                       second, NULL);
 120         case SEMTIMEDOP:
 121                 return sys_semtimedop(first, (struct sembuf __user *)ptr,
 122                                       second, (const struct timespec __user *)fifth);
 123         case SEMGET:
 124                 return sys_semget (first, second, third);
 125         case SEMCTL: {
 126                 union semun fourth;
 127                 if (!ptr)
 128                         return -EINVAL;
 129                 if (get_user(fourth.__pad, (void __user * __user *) ptr))
 130                         return -EFAULT;
 131                 return sys_semctl (first, second, third, fourth);
 132                 }
 133
 134         case MSGSND:
 135                 return sys_msgsnd (first, (struct msgbuf __user *) ptr,
 136                                    second, third);
 137         case MSGRCV:
 138                 switch (version) {
 139                 case 0: {
 140                         struct ipc_kludge tmp;
 141                         if (!ptr)
 142                                 return -EINVAL;
 143
 144                         if (copy_from_user(&tmp,
 145                                            (struct ipc_kludge __user *) ptr,
 146                                            sizeof (tmp)))
 147                                 return -EFAULT;
 148                         return sys_msgrcv (first, tmp.msgp, second,
 149                                            tmp.msgtyp, third);
 150                         }
 151                 default:
 152                         return sys_msgrcv (first,
 153                                            (struct msgbuf __user *) ptr,
 154                                            second, fifth, third);
 155                 }
 156         case MSGGET:
 157                 return sys_msgget ((key_t) first, second);
 158         case MSGCTL:
 159                 return sys_msgctl (first, second,
 160                                    (struct msqid_ds __user *) ptr);
 161         case SHMAT: {
 162                 ulong raddr;
 163
 164                 if (!access_ok(VERIFY_WRITE, (ulong __user *) third,
 165                                       sizeof(ulong)))
 166                         return -EFAULT;
 167                 ret = do_shmat (first, (char __user *) ptr, second, &raddr);
 168                 if (ret)
 169                         return ret;
 170                 return put_user (raddr, (ulong __user *) third);
 171                 }
 172         case SHMDT:
 173                 return sys_shmdt ((char __user *)ptr);
 174         case SHMGET:
 175                 return sys_shmget (first, second, third);
 176         case SHMCTL:
 177                 return sys_shmctl (first, second,
 178                                    (struct shmid_ds __user *) ptr);
 179         default:
 180                 return -ENOSYS;
 181         }
 182 }
 183
 184 asmlinkage int sys_uname(struct old_utsname __user * name)
 185 {
 186         int err;
 187         if (!name)
 188                 return -EFAULT;
 189         down_read(&uts_sem);
 190         err = copy_to_user(name, utsname(), sizeof (*name));
 191         up_read(&uts_sem);
 192         return err?-EFAULT:0;
 193 }
 194
 195 asmlinkage int sys_cacheflush(void *addr, int bytes, int cache)
 196 {
 197         /* This should flush more selectively ...  */
 198         _flush_cache_all();
 199         return 0;
 200 }
 201
 202 asmlinkage int sys_cachectl(char *addr, int nbytes, int op)
 203 {
 204         /* Not implemented yet. */
 205         return -ENOSYS;
 206 }
 207
 208 /*
 209  * Do a system call from kernel instead of calling sys_execve so we
 210  * end up with proper pt_regs.
 211  */
 212 int kernel_execve(const char *filename, char *const argv[], char *const envp[])
 213 {
 214         register long __scno __asm__ ("r7") = __NR_execve;
 215         register long __arg3 __asm__ ("r2") = (long)(envp);
 216         register long __arg2 __asm__ ("r1") = (long)(argv);
 217         register long __res __asm__ ("r0") = (long)(filename);
 218         __asm__ __volatile__ (
 219                 "trap #" SYSCALL_VECTOR "|| nop"
 220                 : "=r" (__res)
 221                 : "r" (__scno), "0" (__res), "r" (__arg2),
 222                         "r" (__arg3)
 223                 : "memory");
 224         return __res;
 225 }