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