arch/powerpc/kernel/syscalls.c

   1 /*
   2  *  Implementation of various system calls for Linux/PowerPC
   3  *
   4  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
   5  *
   6  * Derived from "arch/i386/kernel/sys_i386.c"
   7  * Adapted from the i386 version by Gary Thomas
   8  * Modified by Cort Dougan (cort@cs.nmt.edu)
   9  * and Paul Mackerras (paulus@cs.anu.edu.au).
  10  *
  11  * This file contains various random system calls that
  12  * have a non-standard calling sequence on the Linux/PPC
  13  * platform.
  14  *
  15  *  This program is free software; you can redistribute it and/or
  16  *  modify it under the terms of the GNU General Public License
  17  *  as published by the Free Software Foundation; either version
  18  *  2 of the License, or (at your option) any later version.
  19  *
  20  */
  21
  22 #include <linux/errno.h>
  23 #include <linux/sched.h>
  24 #include <linux/syscalls.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/mman.h>
  33 #include <linux/sys.h>
  34 #include <linux/ipc.h>
  35 #include <linux/utsname.h>
  36 #include <linux/file.h>
  37 #include <linux/init.h>
  38 #include <linux/personality.h>
  39
  40 #include <asm/uaccess.h>
  41 #include <asm/ipc.h>
  42 #include <asm/semaphore.h>
  43 #include <asm/syscalls.h>
  44 #include <asm/time.h>
  45 #include <asm/unistd.h>
  46
  47 /*
  48  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
  49  *
  50  * This is really horribly ugly.
  51  */
  52 int sys_ipc(uint call, int first, unsigned long second, long third,
  53             void __user *ptr, long fifth)
  54 {
  55         int version, ret;
  56
  57         version = call >> 16; /* hack for backward compatibility */
  58         call &= 0xffff;
  59
  60         ret = -ENOSYS;
  61         switch (call) {
  62         case SEMOP:
  63                 ret = sys_semtimedop(first, (struct sembuf __user *)ptr,
  64                                       (unsigned)second, NULL);
  65                 break;
  66         case SEMTIMEDOP:
  67                 ret = sys_semtimedop(first, (struct sembuf __user *)ptr,
  68                                       (unsigned)second,
  69                                       (const struct timespec __user *) fifth);
  70                 break;
  71         case SEMGET:
  72                 ret = sys_semget (first, (int)second, third);
  73                 break;
  74         case SEMCTL: {
  75                 union semun fourth;
  76
  77                 ret = -EINVAL;
  78                 if (!ptr)
  79                         break;
  80                 if ((ret = get_user(fourth.__pad, (void __user * __user *)ptr)))
  81                         break;
  82                 ret = sys_semctl(first, (int)second, third, fourth);
  83                 break;
  84         }
  85         case MSGSND:
  86                 ret = sys_msgsnd(first, (struct msgbuf __user *)ptr,
  87                                  (size_t)second, third);
  88                 break;
  89         case MSGRCV:
  90                 switch (version) {
  91                 case 0: {
  92                         struct ipc_kludge tmp;
  93
  94                         ret = -EINVAL;
  95                         if (!ptr)
  96                                 break;
  97                         if ((ret = copy_from_user(&tmp,
  98                                                 (struct ipc_kludge __user *) ptr,
  99                                                 sizeof (tmp)) ? -EFAULT : 0))
 100                                 break;
 101                         ret = sys_msgrcv(first, tmp.msgp, (size_t) second,
 102                                           tmp.msgtyp, third);
 103                         break;
 104                 }
 105                 default:
 106                         ret = sys_msgrcv (first, (struct msgbuf __user *) ptr,
 107                                           (size_t)second, fifth, third);
 108                         break;
 109                 }
 110                 break;
 111         case MSGGET:
 112                 ret = sys_msgget((key_t)first, (int)second);
 113                 break;
 114         case MSGCTL:
 115                 ret = sys_msgctl(first, (int)second,
 116                                   (struct msqid_ds __user *)ptr);
 117                 break;
 118         case SHMAT: {
 119                 ulong raddr;
 120                 ret = do_shmat(first, (char __user *)ptr, (int)second, &raddr);
 121                 if (ret)
 122                         break;
 123                 ret = put_user(raddr, (ulong __user *) third);
 124                 break;
 125         }
 126         case SHMDT:
 127                 ret = sys_shmdt((char __user *)ptr);
 128                 break;
 129         case SHMGET:
 130                 ret = sys_shmget(first, (size_t)second, third);
 131                 break;
 132         case SHMCTL:
 133                 ret = sys_shmctl(first, (int)second,
 134                                  (struct shmid_ds __user *)ptr);
 135                 break;
 136         }
 137
 138         return ret;
 139 }
 140
 141 /*
 142  * sys_pipe() is the normal C calling standard for creating
 143  * a pipe. It's not the way unix traditionally does this, though.
 144  */
 145 int sys_pipe(int __user *fildes)
 146 {
 147         int fd[2];
 148         int error;
 149
 150         error = do_pipe(fd);
 151         if (!error) {
 152                 if (copy_to_user(fildes, fd, 2*sizeof(int)))
 153                         error = -EFAULT;
 154         }
 155         return error;
 156 }
 157
 158 static inline unsigned long do_mmap2(unsigned long addr, size_t len,
 159                         unsigned long prot, unsigned long flags,
 160                         unsigned long fd, unsigned long off, int shift)
 161 {
 162         struct file * file = NULL;
 163         unsigned long ret = -EINVAL;
 164
 165         if (shift) {
 166                 if (off & ((1 << shift) - 1))
 167                         goto out;
 168                 off >>= shift;
 169         }
 170
 171         ret = -EBADF;
 172         if (!(flags & MAP_ANONYMOUS)) {
 173                 if (!(file = fget(fd)))
 174                         goto out;
 175         }
 176
 177         flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
 178
 179         down_write(&current->mm->mmap_sem);
 180         ret = do_mmap_pgoff(file, addr, len, prot, flags, off);
 181         up_write(&current->mm->mmap_sem);
 182         if (file)
 183                 fput(file);
 184 out:
 185         return ret;
 186 }
 187
 188 unsigned long sys_mmap2(unsigned long addr, size_t len,
 189                         unsigned long prot, unsigned long flags,
 190                         unsigned long fd, unsigned long pgoff)
 191 {
 192         return do_mmap2(addr, len, prot, flags, fd, pgoff, PAGE_SHIFT-12);
 193 }
 194
 195 unsigned long sys_mmap(unsigned long addr, size_t len,
 196                        unsigned long prot, unsigned long flags,
 197                        unsigned long fd, off_t offset)
 198 {
 199         return do_mmap2(addr, len, prot, flags, fd, offset, PAGE_SHIFT);
 200 }
 201
 202 #ifdef CONFIG_PPC32
 203 /*
 204  * Due to some executables calling the wrong select we sometimes
 205  * get wrong args.  This determines how the args are being passed
 206  * (a single ptr to them all args passed) then calls
 207  * sys_select() with the appropriate args. -- Cort
 208  */
 209 int
 210 ppc_select(int n, fd_set __user *inp, fd_set __user *outp, fd_set __user *exp, struct timeval __user *tvp)
 211 {
 212         if ( (unsigned long)n >= 4096 )
 213         {
 214                 unsigned long __user *buffer = (unsigned long __user *)n;
 215                 if (!access_ok(VERIFY_READ, buffer, 5*sizeof(unsigned long))
 216                     || __get_user(n, buffer)
 217                     || __get_user(inp, ((fd_set __user * __user *)(buffer+1)))
 218                     || __get_user(outp, ((fd_set  __user * __user *)(buffer+2)))
 219                     || __get_user(exp, ((fd_set  __user * __user *)(buffer+3)))
 220                     || __get_user(tvp, ((struct timeval  __user * __user *)(buffer+4))))
 221                         return -EFAULT;
 222         }
 223         return sys_select(n, inp, outp, exp, tvp);
 224 }
 225 #endif
 226
 227 #ifdef CONFIG_PPC64
 228 long ppc64_personality(unsigned long personality)
 229 {
 230         long ret;
 231
 232         if (personality(current->personality) == PER_LINUX32
 233             && personality == PER_LINUX)
 234                 personality = PER_LINUX32;
 235         ret = sys_personality(personality);
 236         if (ret == PER_LINUX32)
 237                 ret = PER_LINUX;
 238         return ret;
 239 }
 240 #endif
 241
 242 #ifdef CONFIG_PPC64
 243 #define OVERRIDE_MACHINE    (personality(current->personality) == PER_LINUX32)
 244 #else
 245 #define OVERRIDE_MACHINE    0
 246 #endif
 247
 248 static inline int override_machine(char __user *mach)
 249 {
 250         if (OVERRIDE_MACHINE) {
 251                 /* change ppc64 to ppc */
 252                 if (__put_user(0, mach+3) || __put_user(0, mach+4))
 253                         return -EFAULT;
 254         }
 255         return 0;
 256 }
 257
 258 long ppc_newuname(struct new_utsname __user * name)
 259 {
 260         int err = 0;
 261
 262         down_read(&uts_sem);
 263         if (copy_to_user(name, &system_utsname, sizeof(*name)))
 264                 err = -EFAULT;
 265         up_read(&uts_sem);
 266         if (!err)
 267                 err = override_machine(name->machine);
 268         return err;
 269 }
 270
 271 int sys_uname(struct old_utsname __user *name)
 272 {
 273         int err = 0;
 274
 275         down_read(&uts_sem);
 276         if (copy_to_user(name, &system_utsname, sizeof(*name)))
 277                 err = -EFAULT;
 278         up_read(&uts_sem);
 279         if (!err)
 280                 err = override_machine(name->machine);
 281         return err;
 282 }
 283
 284 int sys_olduname(struct oldold_utsname __user *name)
 285 {
 286         int error;
 287
 288         if (!access_ok(VERIFY_WRITE, name, sizeof(struct oldold_utsname)))
 289                 return -EFAULT;
 290
 291         down_read(&uts_sem);
 292         error = __copy_to_user(&name->sysname, &system_utsname.sysname,
 293                                __OLD_UTS_LEN);
 294         error |= __put_user(0, name->sysname + __OLD_UTS_LEN);
 295         error |= __copy_to_user(&name->nodename, &system_utsname.nodename,
 296                                 __OLD_UTS_LEN);
 297         error |= __put_user(0, name->nodename + __OLD_UTS_LEN);
 298         error |= __copy_to_user(&name->release, &system_utsname.release,
 299                                 __OLD_UTS_LEN);
 300         error |= __put_user(0, name->release + __OLD_UTS_LEN);
 301         error |= __copy_to_user(&name->version, &system_utsname.version,
 302                                 __OLD_UTS_LEN);
 303         error |= __put_user(0, name->version + __OLD_UTS_LEN);
 304         error |= __copy_to_user(&name->machine, &system_utsname.machine,
 305                                 __OLD_UTS_LEN);
 306         error |= override_machine(name->machine);
 307         up_read(&uts_sem);
 308
 309         return error? -EFAULT: 0;
 310 }
 311
 312 long ppc_fadvise64_64(int fd, int advice, u32 offset_high, u32 offset_low,
 313                       u32 len_high, u32 len_low)
 314 {
 315         return sys_fadvise64(fd, (u64)offset_high << 32 | offset_low,
 316                              (u64)len_high << 32 | len_low, advice);
 317 }
 318
 319 void do_show_syscall(unsigned long r3, unsigned long r4, unsigned long r5,
 320                      unsigned long r6, unsigned long r7, unsigned long r8,
 321                      struct pt_regs *regs)
 322 {
 323         printk("syscall %ld(%lx, %lx, %lx, %lx, %lx, %lx) regs=%p current=%p"
 324                " cpu=%d\n", regs->gpr[0], r3, r4, r5, r6, r7, r8, regs,
 325                current, smp_processor_id());
 326 }
 327
 328 void do_show_syscall_exit(unsigned long r3)
 329 {
 330         printk(" -> %lx, current=%p cpu=%d\n", r3, current, smp_processor_id());
 331 }