arch/mips/kernel/syscall.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 1995, 1996, 1997, 2000, 2001, 05 by Ralf Baechle
   7  * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
   8  * Copyright (C) 2001 MIPS Technologies, Inc.
   9  */
  10 #include <linux/config.h>
  11 #include <linux/a.out.h>
  12 #include <linux/capability.h>
  13 #include <linux/errno.h>
  14 #include <linux/linkage.h>
  15 #include <linux/mm.h>
  16 #include <linux/smp.h>
  17 #include <linux/smp_lock.h>
  18 #include <linux/mman.h>
  19 #include <linux/ptrace.h>
  20 #include <linux/sched.h>
  21 #include <linux/string.h>
  22 #include <linux/syscalls.h>
  23 #include <linux/file.h>
  24 #include <linux/slab.h>
  25 #include <linux/utsname.h>
  26 #include <linux/unistd.h>
  27 #include <linux/sem.h>
  28 #include <linux/msg.h>
  29 #include <linux/shm.h>
  30 #include <linux/compiler.h>
  31 #include <linux/module.h>
  32
  33 #include <asm/branch.h>
  34 #include <asm/cachectl.h>
  35 #include <asm/cacheflush.h>
  36 #include <asm/ipc.h>
  37 #include <asm/asm-offsets.h>
  38 #include <asm/signal.h>
  39 #include <asm/sim.h>
  40 #include <asm/shmparam.h>
  41 #include <asm/sysmips.h>
  42 #include <asm/uaccess.h>
  43
  44 asmlinkage int sys_pipe(nabi_no_regargs volatile struct pt_regs regs)
  45 {
  46         int fd[2];
  47         int error, res;
  48
  49         error = do_pipe(fd);
  50         if (error) {
  51                 res = error;
  52                 goto out;
  53         }
  54         regs.regs[3] = fd[1];
  55         res = fd[0];
  56 out:
  57         return res;
  58 }
  59
  60 unsigned long shm_align_mask = PAGE_SIZE - 1;   /* Sane caches */
  61
  62 EXPORT_SYMBOL(shm_align_mask);
  63
  64 #define COLOUR_ALIGN(addr,pgoff)                                \
  65         ((((addr) + shm_align_mask) & ~shm_align_mask) +        \
  66          (((pgoff) << PAGE_SHIFT) & shm_align_mask))
  67
  68 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
  69         unsigned long len, unsigned long pgoff, unsigned long flags)
  70 {
  71         struct vm_area_struct * vmm;
  72         int do_color_align;
  73         unsigned long task_size;
  74
  75         task_size = STACK_TOP;
  76
  77         if (flags & MAP_FIXED) {
  78                 /*
  79                  * We do not accept a shared mapping if it would violate
  80                  * cache aliasing constraints.
  81                  */
  82                 if ((flags & MAP_SHARED) && (addr & shm_align_mask))
  83                         return -EINVAL;
  84                 return addr;
  85         }
  86
  87         if (len > task_size)
  88                 return -ENOMEM;
  89         do_color_align = 0;
  90         if (filp || (flags & MAP_SHARED))
  91                 do_color_align = 1;
  92         if (addr) {
  93                 if (do_color_align)
  94                         addr = COLOUR_ALIGN(addr, pgoff);
  95                 else
  96                         addr = PAGE_ALIGN(addr);
  97                 vmm = find_vma(current->mm, addr);
  98                 if (task_size - len >= addr &&
  99                     (!vmm || addr + len <= vmm->vm_start))
 100                         return addr;
 101         }
 102         addr = TASK_UNMAPPED_BASE;
 103         if (do_color_align)
 104                 addr = COLOUR_ALIGN(addr, pgoff);
 105         else
 106                 addr = PAGE_ALIGN(addr);
 107
 108         for (vmm = find_vma(current->mm, addr); ; vmm = vmm->vm_next) {
 109                 /* At this point:  (!vmm || addr < vmm->vm_end). */
 110                 if (task_size - len < addr)
 111                         return -ENOMEM;
 112                 if (!vmm || addr + len <= vmm->vm_start)
 113                         return addr;
 114                 addr = vmm->vm_end;
 115                 if (do_color_align)
 116                         addr = COLOUR_ALIGN(addr, pgoff);
 117         }
 118 }
 119
 120 /* common code for old and new mmaps */
 121 static inline unsigned long
 122 do_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
 123         unsigned long flags, unsigned long fd, unsigned long pgoff)
 124 {
 125         unsigned long error = -EBADF;
 126         struct file * file = NULL;
 127
 128         flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
 129         if (!(flags & MAP_ANONYMOUS)) {
 130                 file = fget(fd);
 131                 if (!file)
 132                         goto out;
 133         }
 134
 135         down_write(&current->mm->mmap_sem);
 136         error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
 137         up_write(&current->mm->mmap_sem);
 138
 139         if (file)
 140                 fput(file);
 141 out:
 142         return error;
 143 }
 144
 145 asmlinkage unsigned long
 146 old_mmap(unsigned long addr, unsigned long len, int prot,
 147         int flags, int fd, off_t offset)
 148 {
 149         unsigned long result;
 150
 151         result = -EINVAL;
 152         if (offset & ~PAGE_MASK)
 153                 goto out;
 154
 155         result = do_mmap2(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
 156
 157 out:
 158         return result;
 159 }
 160
 161 asmlinkage unsigned long
 162 sys_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
 163           unsigned long flags, unsigned long fd, unsigned long pgoff)
 164 {
 165         return do_mmap2(addr, len, prot, flags, fd, pgoff);
 166 }
 167
 168 save_static_function(sys_fork);
 169 __attribute_used__ noinline static int
 170 _sys_fork(nabi_no_regargs struct pt_regs regs)
 171 {
 172         return do_fork(SIGCHLD, regs.regs[29], &regs, 0, NULL, NULL);
 173 }
 174
 175 save_static_function(sys_clone);
 176 __attribute_used__ noinline static int
 177 _sys_clone(nabi_no_regargs struct pt_regs regs)
 178 {
 179         unsigned long clone_flags;
 180         unsigned long newsp;
 181         int __user *parent_tidptr, *child_tidptr;
 182
 183         clone_flags = regs.regs[4];
 184         newsp = regs.regs[5];
 185         if (!newsp)
 186                 newsp = regs.regs[29];
 187         parent_tidptr = (int __user *) regs.regs[6];
 188 #ifdef CONFIG_32BIT
 189         /* We need to fetch the fifth argument off the stack.  */
 190         child_tidptr = NULL;
 191         if (clone_flags & (CLONE_CHILD_SETTID | CLONE_CHILD_CLEARTID)) {
 192                 int __user *__user *usp = (int __user *__user *) regs.regs[29];
 193                 if (regs.regs[2] == __NR_syscall) {
 194                         if (get_user (child_tidptr, &usp[5]))
 195                                 return -EFAULT;
 196                 }
 197                 else if (get_user (child_tidptr, &usp[4]))
 198                         return -EFAULT;
 199         }
 200 #else
 201         child_tidptr = (int __user *) regs.regs[8];
 202 #endif
 203         return do_fork(clone_flags, newsp, &regs, 0,
 204                        parent_tidptr, child_tidptr);
 205 }
 206
 207 /*
 208  * sys_execve() executes a new program.
 209  */
 210 asmlinkage int sys_execve(nabi_no_regargs struct pt_regs regs)
 211 {
 212         int error;
 213         char * filename;
 214
 215         filename = getname((char __user *) (long)regs.regs[4]);
 216         error = PTR_ERR(filename);
 217         if (IS_ERR(filename))
 218                 goto out;
 219         error = do_execve(filename, (char __user *__user *) (long)regs.regs[5],
 220                           (char __user *__user *) (long)regs.regs[6], &regs);
 221         putname(filename);
 222
 223 out:
 224         return error;
 225 }
 226
 227 /*
 228  * Compacrapability ...
 229  */
 230 asmlinkage int sys_uname(struct old_utsname __user * name)
 231 {
 232         if (name && !copy_to_user(name, &system_utsname, sizeof (*name)))
 233                 return 0;
 234         return -EFAULT;
 235 }
 236
 237 /*
 238  * Compacrapability ...
 239  */
 240 asmlinkage int sys_olduname(struct oldold_utsname __user * name)
 241 {
 242         int error;
 243
 244         if (!name)
 245                 return -EFAULT;
 246         if (!access_ok(VERIFY_WRITE,name,sizeof(struct oldold_utsname)))
 247                 return -EFAULT;
 248
 249         error = __copy_to_user(&name->sysname,&system_utsname.sysname,__OLD_UTS_LEN);
 250         error -= __put_user(0,name->sysname+__OLD_UTS_LEN);
 251         error -= __copy_to_user(&name->nodename,&system_utsname.nodename,__OLD_UTS_LEN);
 252         error -= __put_user(0,name->nodename+__OLD_UTS_LEN);
 253         error -= __copy_to_user(&name->release,&system_utsname.release,__OLD_UTS_LEN);
 254         error -= __put_user(0,name->release+__OLD_UTS_LEN);
 255         error -= __copy_to_user(&name->version,&system_utsname.version,__OLD_UTS_LEN);
 256         error -= __put_user(0,name->version+__OLD_UTS_LEN);
 257         error -= __copy_to_user(&name->machine,&system_utsname.machine,__OLD_UTS_LEN);
 258         error = __put_user(0,name->machine+__OLD_UTS_LEN);
 259         error = error ? -EFAULT : 0;
 260
 261         return error;
 262 }
 263
 264 void sys_set_thread_area(unsigned long addr)
 265 {
 266         struct thread_info *ti = task_thread_info(current);
 267
 268         ti->tp_value = addr;
 269
 270         /* If some future MIPS implementation has this register in hardware,
 271          * we will need to update it here (and in context switches).  */
 272 }
 273
 274 asmlinkage int _sys_sysmips(int cmd, long arg1, int arg2, int arg3)
 275 {
 276         int     tmp, len;
 277         char    __user *name;
 278
 279         switch(cmd) {
 280         case SETNAME: {
 281                 char nodename[__NEW_UTS_LEN + 1];
 282
 283                 if (!capable(CAP_SYS_ADMIN))
 284                         return -EPERM;
 285
 286                 name = (char __user *) arg1;
 287
 288                 len = strncpy_from_user(nodename, name, __NEW_UTS_LEN);
 289                 if (len < 0)
 290                         return -EFAULT;
 291
 292                 down_write(&uts_sem);
 293                 strncpy(system_utsname.nodename, nodename, len);
 294                 nodename[__NEW_UTS_LEN] = '\0';
 295                 strlcpy(system_utsname.nodename, nodename,
 296                         sizeof(system_utsname.nodename));
 297                 up_write(&uts_sem);
 298                 return 0;
 299         }
 300
 301         case MIPS_ATOMIC_SET:
 302                 printk(KERN_CRIT "How did I get here?\n");
 303                 return -EINVAL;
 304
 305         case MIPS_FIXADE:
 306                 tmp = current->thread.mflags & ~3;
 307                 current->thread.mflags = tmp | (arg1 & 3);
 308                 return 0;
 309
 310         case FLUSH_CACHE:
 311                 __flush_cache_all();
 312                 return 0;
 313
 314         case MIPS_RDNVRAM:
 315                 return -EIO;
 316         }
 317
 318         return -EINVAL;
 319 }
 320
 321 /*
 322  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
 323  *
 324  * This is really horribly ugly.
 325  */
 326 asmlinkage int sys_ipc (uint call, int first, int second,
 327                         unsigned long third, void __user *ptr, long fifth)
 328 {
 329         int version, ret;
 330
 331         version = call >> 16; /* hack for backward compatibility */
 332         call &= 0xffff;
 333
 334         switch (call) {
 335         case SEMOP:
 336                 return sys_semtimedop (first, (struct sembuf __user *)ptr,
 337                                        second, NULL);
 338         case SEMTIMEDOP:
 339                 return sys_semtimedop (first, (struct sembuf __user *)ptr,
 340                                        second,
 341                                        (const struct timespec __user *)fifth);
 342         case SEMGET:
 343                 return sys_semget (first, second, third);
 344         case SEMCTL: {
 345                 union semun fourth;
 346                 if (!ptr)
 347                         return -EINVAL;
 348                 if (get_user(fourth.__pad, (void *__user *) ptr))
 349                         return -EFAULT;
 350                 return sys_semctl (first, second, third, fourth);
 351         }
 352
 353         case MSGSND:
 354                 return sys_msgsnd (first, (struct msgbuf __user *) ptr,
 355                                    second, third);
 356         case MSGRCV:
 357                 switch (version) {
 358                 case 0: {
 359                         struct ipc_kludge tmp;
 360                         if (!ptr)
 361                                 return -EINVAL;
 362
 363                         if (copy_from_user(&tmp,
 364                                            (struct ipc_kludge __user *) ptr,
 365                                            sizeof (tmp)))
 366                                 return -EFAULT;
 367                         return sys_msgrcv (first, tmp.msgp, second,
 368                                            tmp.msgtyp, third);
 369                 }
 370                 default:
 371                         return sys_msgrcv (first,
 372                                            (struct msgbuf __user *) ptr,
 373                                            second, fifth, third);
 374                 }
 375         case MSGGET:
 376                 return sys_msgget ((key_t) first, second);
 377         case MSGCTL:
 378                 return sys_msgctl (first, second,
 379                                    (struct msqid_ds __user *) ptr);
 380
 381         case SHMAT:
 382                 switch (version) {
 383                 default: {
 384                         ulong raddr;
 385                         ret = do_shmat (first, (char __user *) ptr, second,
 386                                         &raddr);
 387                         if (ret)
 388                                 return ret;
 389                         return put_user (raddr, (ulong __user *) third);
 390                 }
 391                 case 1: /* iBCS2 emulator entry point */
 392                         if (!segment_eq(get_fs(), get_ds()))
 393                                 return -EINVAL;
 394                         return do_shmat (first, (char __user *) ptr, second,
 395                                          (ulong *) third);
 396                 }
 397         case SHMDT:
 398                 return sys_shmdt ((char __user *)ptr);
 399         case SHMGET:
 400                 return sys_shmget (first, second, third);
 401         case SHMCTL:
 402                 return sys_shmctl (first, second,
 403                                    (struct shmid_ds __user *) ptr);
 404         default:
 405                 return -ENOSYS;
 406         }
 407 }
 408
 409 /*
 410  * No implemented yet ...
 411  */
 412 asmlinkage int sys_cachectl(char *addr, int nbytes, int op)
 413 {
 414         return -ENOSYS;
 415 }
 416
 417 /*
 418  * If we ever come here the user sp is bad.  Zap the process right away.
 419  * Due to the bad stack signaling wouldn't work.
 420  */
 421 asmlinkage void bad_stack(void)
 422 {
 423         do_exit(SIGSEGV);
 424 }