arch/m68knommu/kernel/sys_m68k.c

   1 /*
   2  * linux/arch/m68knommu/kernel/sys_m68k.c
   3  *
   4  * This file contains various random system calls that
   5  * have a non-standard calling sequence on the Linux/m68k
   6  * platform.
   7  */
   8
   9 #include <linux/errno.h>
  10 #include <linux/sched.h>
  11 #include <linux/mm.h>
  12 #include <linux/smp.h>
  13 #include <linux/sem.h>
  14 #include <linux/msg.h>
  15 #include <linux/shm.h>
  16 #include <linux/stat.h>
  17 #include <linux/syscalls.h>
  18 #include <linux/mman.h>
  19 #include <linux/file.h>
  20 #include <linux/ipc.h>
  21 #include <linux/fs.h>
  22
  23 #include <asm/setup.h>
  24 #include <asm/uaccess.h>
  25 #include <asm/cachectl.h>
  26 #include <asm/traps.h>
  27 #include <asm/cacheflush.h>
  28 #include <asm/unistd.h>
  29
  30 /*
  31  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
  32  *
  33  * This is really horribly ugly.
  34  */
  35 asmlinkage int sys_ipc (uint call, int first, int second,
  36                         int third, void *ptr, long fifth)
  37 {
  38         int version, ret;
  39
  40         version = call >> 16; /* hack for backward compatibility */
  41         call &= 0xffff;
  42
  43         if (call <= SEMCTL)
  44                 switch (call) {
  45                 case SEMOP:
  46                         return sys_semop (first, (struct sembuf *)ptr, second);
  47                 case SEMGET:
  48                         return sys_semget (first, second, third);
  49                 case SEMCTL: {
  50                         union semun fourth;
  51                         if (!ptr)
  52                                 return -EINVAL;
  53                         if (get_user(fourth.__pad, (void **) ptr))
  54                                 return -EFAULT;
  55                         return sys_semctl (first, second, third, fourth);
  56                         }
  57                 default:
  58                         return -EINVAL;
  59                 }
  60         if (call <= MSGCTL)
  61                 switch (call) {
  62                 case MSGSND:
  63                         return sys_msgsnd (first, (struct msgbuf *) ptr,
  64                                           second, third);
  65                 case MSGRCV:
  66                         switch (version) {
  67                         case 0: {
  68                                 struct ipc_kludge tmp;
  69                                 if (!ptr)
  70                                         return -EINVAL;
  71                                 if (copy_from_user (&tmp,
  72                                                     (struct ipc_kludge *)ptr,
  73                                                     sizeof (tmp)))
  74                                         return -EFAULT;
  75                                 return sys_msgrcv (first, tmp.msgp, second,
  76                                                    tmp.msgtyp, third);
  77                                 }
  78                         default:
  79                                 return sys_msgrcv (first,
  80                                                    (struct msgbuf *) ptr,
  81                                                    second, fifth, third);
  82                         }
  83                 case MSGGET:
  84                         return sys_msgget ((key_t) first, second);
  85                 case MSGCTL:
  86                         return sys_msgctl (first, second,
  87                                            (struct msqid_ds *) ptr);
  88                 default:
  89                         return -EINVAL;
  90                 }
  91         if (call <= SHMCTL)
  92                 switch (call) {
  93                 case SHMAT:
  94                         switch (version) {
  95                         default: {
  96                                 ulong raddr;
  97                                 ret = do_shmat (first, ptr, second, &raddr);
  98                                 if (ret)
  99                                         return ret;
 100                                 return put_user (raddr, (ulong __user *) third);
 101                         }
 102                         }
 103                 case SHMDT:
 104                         return sys_shmdt (ptr);
 105                 case SHMGET:
 106                         return sys_shmget (first, second, third);
 107                 case SHMCTL:
 108                         return sys_shmctl (first, second, ptr);
 109                 default:
 110                         return -ENOSYS;
 111                 }
 112
 113         return -EINVAL;
 114 }
 115
 116 /* sys_cacheflush -- flush (part of) the processor cache.  */
 117 asmlinkage int
 118 sys_cacheflush (unsigned long addr, int scope, int cache, unsigned long len)
 119 {
 120         flush_cache_all();
 121         return(0);
 122 }
 123
 124 asmlinkage int sys_getpagesize(void)
 125 {
 126         return PAGE_SIZE;
 127 }
 128
 129 /*
 130  * Do a system call from kernel instead of calling sys_execve so we
 131  * end up with proper pt_regs.
 132  */
 133 int kernel_execve(const char *filename, char *const argv[], char *const envp[])
 134 {
 135         register long __res asm ("%d0") = __NR_execve;
 136         register long __a asm ("%d1") = (long)(filename);
 137         register long __b asm ("%d2") = (long)(argv);
 138         register long __c asm ("%d3") = (long)(envp);
 139         asm volatile ("trap  #0" : "+d" (__res)
 140                         : "d" (__a), "d" (__b), "d" (__c));
 141         return __res;
 142 }
 143
 144 asmlinkage unsigned long sys_get_thread_area(void)
 145 {
 146         return current_thread_info()->tp_value;
 147 }
 148
 149 asmlinkage int sys_set_thread_area(unsigned long tp)
 150 {
 151         current_thread_info()->tp_value = tp;
 152         return 0;
 153 }
 154
 155 /* This syscall gets its arguments in A0 (mem), D2 (oldval) and
 156    D1 (newval).  */
 157 asmlinkage int
 158 sys_atomic_cmpxchg_32(unsigned long newval, int oldval, int d3, int d4, int d5,
 159                       unsigned long __user * mem)
 160 {
 161         struct mm_struct *mm = current->mm;
 162         unsigned long mem_value;
 163
 164         down_read(&mm->mmap_sem);
 165
 166         mem_value = *mem;
 167         if (mem_value == oldval)
 168                 *mem = newval;
 169
 170         up_read(&mm->mmap_sem);
 171         return mem_value;
 172 }
 173
 174 asmlinkage int sys_atomic_barrier(void)
 175 {
 176         /* no code needed for uniprocs */
 177         return 0;
 178 }