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