arch/ppc/kernel/syscalls.c

   1 /*
   2  * arch/ppc/kernel/sys_ppc.c
   3  *
   4  *  PowerPC version
   5  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
   6  *
   7  * Derived from "arch/i386/kernel/sys_i386.c"
   8  * Adapted from the i386 version by Gary Thomas
   9  * Modified by Cort Dougan (cort@cs.nmt.edu)
  10  * and Paul Mackerras (paulus@cs.anu.edu.au).
  11  *
  12  * This file contains various random system calls that
  13  * have a non-standard calling sequence on the Linux/PPC
  14  * platform.
  15  *
  16  *  This program is free software; you can redistribute it and/or
  17  *  modify it under the terms of the GNU General Public License
  18  *  as published by the Free Software Foundation; either version
  19  *  2 of the License, or (at your option) any later version.
  20  *
  21  */
  22
  23 #include <linux/errno.h>
  24 #include <linux/sched.h>
  25 #include <linux/mm.h>
  26 #include <linux/smp.h>
  27 #include <linux/smp_lock.h>
  28 #include <linux/sem.h>
  29 #include <linux/msg.h>
  30 #include <linux/shm.h>
  31 #include <linux/stat.h>
  32 #include <linux/syscalls.h>
  33 #include <linux/mman.h>
  34 #include <linux/sys.h>
  35 #include <linux/ipc.h>
  36 #include <linux/utsname.h>
  37 #include <linux/file.h>
  38 #include <linux/unistd.h>
  39
  40 #include <asm/uaccess.h>
  41 #include <asm/ipc.h>
  42 #include <asm/semaphore.h>
  43
  44
  45 /*
  46  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
  47  *
  48  * This is really horribly ugly.
  49  */
  50 int
  51 sys_ipc (uint call, int first, int second, int third, void __user *ptr, long fifth)
  52 {
  53         int version, ret;
  54
  55         version = call >> 16; /* hack for backward compatibility */
  56         call &= 0xffff;
  57
  58         ret = -ENOSYS;
  59         switch (call) {
  60         case SEMOP:
  61                 ret = sys_semtimedop (first, (struct sembuf __user *)ptr,
  62                                       second, NULL);
  63                 break;
  64         case SEMTIMEDOP:
  65                 ret = sys_semtimedop (first, (struct sembuf __user *)ptr,
  66                                       second, (const struct timespec __user *) fifth);
  67                 break;
  68         case SEMGET:
  69                 ret = sys_semget (first, second, third);
  70                 break;
  71         case SEMCTL: {
  72                 union semun fourth;
  73
  74                 if (!ptr)
  75                         break;
  76                 if ((ret = access_ok(VERIFY_READ, ptr, sizeof(long)) ? 0 : -EFAULT)
  77                     || (ret = get_user(fourth.__pad, (void __user *__user *)ptr)))
  78                         break;
  79                 ret = sys_semctl (first, second, third, fourth);
  80                 break;
  81                 }
  82         case MSGSND:
  83                 ret = sys_msgsnd (first, (struct msgbuf __user *) ptr, second, third);
  84                 break;
  85         case MSGRCV:
  86                 switch (version) {
  87                 case 0: {
  88                         struct ipc_kludge tmp;
  89
  90                         if (!ptr)
  91                                 break;
  92                         if ((ret = access_ok(VERIFY_READ, ptr, sizeof(tmp)) ? 0 : -EFAULT)
  93                             || (ret = copy_from_user(&tmp,
  94                                         (struct ipc_kludge __user *) ptr,
  95                                         sizeof (tmp)) ? -EFAULT : 0))
  96                                 break;
  97                         ret = sys_msgrcv (first, tmp.msgp, second, tmp.msgtyp,
  98                                           third);
  99                         break;
 100                         }
 101                 default:
 102                         ret = sys_msgrcv (first, (struct msgbuf __user *) ptr,
 103                                           second, fifth, third);
 104                         break;
 105                 }
 106                 break;
 107         case MSGGET:
 108                 ret = sys_msgget ((key_t) first, second);
 109                 break;
 110         case MSGCTL:
 111                 ret = sys_msgctl (first, second, (struct msqid_ds __user *) ptr);
 112                 break;
 113         case SHMAT: {
 114                 ulong raddr;
 115
 116                 if ((ret = access_ok(VERIFY_WRITE, (ulong __user *) third,
 117                                        sizeof(ulong)) ? 0 : -EFAULT))
 118                         break;
 119                 ret = do_shmat (first, (char __user *) ptr, second, &raddr);
 120                 if (ret)
 121                         break;
 122                 ret = put_user (raddr, (ulong __user *) third);
 123                 break;
 124                 }
 125         case SHMDT:
 126                 ret = sys_shmdt ((char __user *)ptr);
 127                 break;
 128         case SHMGET:
 129                 ret = sys_shmget (first, second, third);
 130                 break;
 131         case SHMCTL:
 132                 ret = sys_shmctl (first, second, (struct shmid_ds __user *) ptr);
 133                 break;
 134         }
 135
 136         return ret;
 137 }
 138
 139 /*
 140  * sys_pipe() is the normal C calling standard for creating
 141  * a pipe. It's not the way unix traditionally does this, though.
 142  */
 143 int sys_pipe(int __user *fildes)
 144 {
 145         int fd[2];
 146         int error;
 147
 148         error = do_pipe(fd);
 149         if (!error) {
 150                 if (copy_to_user(fildes, fd, 2*sizeof(int)))
 151                         error = -EFAULT;
 152         }
 153         return error;
 154 }
 155
 156 static inline unsigned long
 157 do_mmap2(unsigned long addr, size_t len,
 158          unsigned long prot, unsigned long flags,
 159          unsigned long fd, unsigned long pgoff)
 160 {
 161         struct file * file = NULL;
 162         int ret = -EBADF;
 163
 164         flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
 165         if (!(flags & MAP_ANONYMOUS)) {
 166                 if (!(file = fget(fd)))
 167                         goto out;
 168         }
 169
 170         down_write(&current->mm->mmap_sem);
 171         ret = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
 172         up_write(&current->mm->mmap_sem);
 173         if (file)
 174                 fput(file);
 175 out:
 176         return ret;
 177 }
 178
 179 unsigned long sys_mmap2(unsigned long addr, size_t len,
 180                         unsigned long prot, unsigned long flags,
 181                         unsigned long fd, unsigned long pgoff)
 182 {
 183         return do_mmap2(addr, len, prot, flags, fd, pgoff);
 184 }
 185
 186 unsigned long sys_mmap(unsigned long addr, size_t len,
 187                        unsigned long prot, unsigned long flags,
 188                        unsigned long fd, off_t offset)
 189 {
 190         int err = -EINVAL;
 191
 192         if (offset & ~PAGE_MASK)
 193                 goto out;
 194
 195         err = do_mmap2(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
 196 out:
 197         return err;
 198 }
 199
 200 /*
 201  * Due to some executables calling the wrong select we sometimes
 202  * get wrong args.  This determines how the args are being passed
 203  * (a single ptr to them all args passed) then calls
 204  * sys_select() with the appropriate args. -- Cort
 205  */
 206 int
 207 ppc_select(int n, fd_set __user *inp, fd_set __user *outp, fd_set __user *exp, struct timeval __user *tvp)
 208 {
 209         if ( (unsigned long)n >= 4096 )
 210         {
 211                 unsigned long __user *buffer = (unsigned long __user *)n;
 212                 if (!access_ok(VERIFY_READ, buffer, 5*sizeof(unsigned long))
 213                     || __get_user(n, buffer)
 214                     || __get_user(inp, ((fd_set __user * __user *)(buffer+1)))
 215                     || __get_user(outp, ((fd_set  __user * __user *)(buffer+2)))
 216                     || __get_user(exp, ((fd_set  __user * __user *)(buffer+3)))
 217                     || __get_user(tvp, ((struct timeval  __user * __user *)(buffer+4))))
 218                         return -EFAULT;
 219         }
 220         return sys_select(n, inp, outp, exp, tvp);
 221 }
 222
 223 int sys_uname(struct old_utsname __user * name)
 224 {
 225         int err = -EFAULT;
 226
 227         down_read(&uts_sem);
 228         if (name && !copy_to_user(name, &system_utsname, sizeof (*name)))
 229                 err = 0;
 230         up_read(&uts_sem);
 231         return err;
 232 }
 233
 234 int sys_olduname(struct oldold_utsname __user * name)
 235 {
 236         int error;
 237
 238         if (!name)
 239                 return -EFAULT;
 240         if (!access_ok(VERIFY_WRITE,name,sizeof(struct oldold_utsname)))
 241                 return -EFAULT;
 242
 243         down_read(&uts_sem);
 244         error = __copy_to_user(&name->sysname,&system_utsname.sysname,__OLD_UTS_LEN);
 245         error -= __put_user(0,name->sysname+__OLD_UTS_LEN);
 246         error -= __copy_to_user(&name->nodename,&system_utsname.nodename,__OLD_UTS_LEN);
 247         error -= __put_user(0,name->nodename+__OLD_UTS_LEN);
 248         error -= __copy_to_user(&name->release,&system_utsname.release,__OLD_UTS_LEN);
 249         error -= __put_user(0,name->release+__OLD_UTS_LEN);
 250         error -= __copy_to_user(&name->version,&system_utsname.version,__OLD_UTS_LEN);
 251         error -= __put_user(0,name->version+__OLD_UTS_LEN);
 252         error -= __copy_to_user(&name->machine,&system_utsname.machine,__OLD_UTS_LEN);
 253         error = __put_user(0,name->machine+__OLD_UTS_LEN);
 254         up_read(&uts_sem);
 255
 256         error = error ? -EFAULT : 0;
 257         return error;
 258 }
 259
 260 /*
 261  * We put the arguments in a different order so we only use 6
 262  * registers for arguments, rather than 7 as sys_fadvise64_64 needs
 263  * (because `offset' goes in r5/r6).
 264  */
 265 long ppc_fadvise64_64(int fd, int advice, loff_t offset, loff_t len)
 266 {
 267         return sys_fadvise64_64(fd, offset, len, advice);
 268 }