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/a.out.h>
  11 #include <linux/capability.h>
  12 #include <linux/errno.h>
  13 #include <linux/linkage.h>
  14 #include <linux/mm.h>
  15 #include <linux/smp.h>
  16 #include <linux/mman.h>
  17 #include <linux/ptrace.h>
  18 #include <linux/sched.h>
  19 #include <linux/string.h>
  20 #include <linux/syscalls.h>
  21 #include <linux/file.h>
  22 #include <linux/slab.h>
  23 #include <linux/utsname.h>
  24 #include <linux/unistd.h>
  25 #include <linux/sem.h>
  26 #include <linux/msg.h>
  27 #include <linux/shm.h>
  28 #include <linux/compiler.h>
  29 #include <linux/module.h>
  30
  31 #include <asm/branch.h>
  32 #include <asm/cachectl.h>
  33 #include <asm/cacheflush.h>
  34 #include <asm/ipc.h>
  35 #include <asm/asm-offsets.h>
  36 #include <asm/signal.h>
  37 #include <asm/sim.h>
  38 #include <asm/shmparam.h>
  39 #include <asm/sysmips.h>
  40 #include <asm/uaccess.h>
  41
  42 asmlinkage int sys_pipe(nabi_no_regargs volatile struct pt_regs regs)
  43 {
  44         int fd[2];
  45         int error, res;
  46
  47         error = do_pipe(fd);
  48         if (error) {
  49                 res = error;
  50                 goto out;
  51         }
  52         regs.regs[3] = fd[1];
  53         res = fd[0];
  54 out:
  55         return res;
  56 }
  57
  58 unsigned long shm_align_mask = PAGE_SIZE - 1;   /* Sane caches */
  59
  60 EXPORT_SYMBOL(shm_align_mask);
  61
  62 #define COLOUR_ALIGN(addr,pgoff)                                \
  63         ((((addr) + shm_align_mask) & ~shm_align_mask) +        \
  64          (((pgoff) << PAGE_SHIFT) & shm_align_mask))
  65
  66 unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
  67         unsigned long len, unsigned long pgoff, unsigned long flags)
  68 {
  69         struct vm_area_struct * vmm;
  70         int do_color_align;
  71         unsigned long task_size;
  72
  73         task_size = STACK_TOP;
  74
  75         if (flags & MAP_FIXED) {
  76                 /*
  77                  * We do not accept a shared mapping if it would violate
  78                  * cache aliasing constraints.
  79                  */
  80                 if ((flags & MAP_SHARED) && (addr & shm_align_mask))
  81                         return -EINVAL;
  82                 return addr;
  83         }
  84
  85         if (len > task_size)
  86                 return -ENOMEM;
  87         do_color_align = 0;
  88         if (filp || (flags & MAP_SHARED))
  89                 do_color_align = 1;
  90         if (addr) {
  91                 if (do_color_align)
  92                         addr = COLOUR_ALIGN(addr, pgoff);
  93                 else
  94                         addr = PAGE_ALIGN(addr);
  95                 vmm = find_vma(current->mm, addr);
  96                 if (task_size - len >= addr &&
  97                     (!vmm || addr + len <= vmm->vm_start))
  98                         return addr;
  99         }
 100         addr = TASK_UNMAPPED_BASE;
 101         if (do_color_align)
 102                 addr = COLOUR_ALIGN(addr, pgoff);
 103         else
 104                 addr = PAGE_ALIGN(addr);
 105
 106         for (vmm = find_vma(current->mm, addr); ; vmm = vmm->vm_next) {
 107                 /* At this point:  (!vmm || addr < vmm->vm_end). */
 108                 if (task_size - len < addr)
 109                         return -ENOMEM;
 110                 if (!vmm || addr + len <= vmm->vm_start)
 111                         return addr;
 112                 addr = vmm->vm_end;
 113                 if (do_color_align)
 114                         addr = COLOUR_ALIGN(addr, pgoff);
 115         }
 116 }
 117
 118 /* common code for old and new mmaps */
 119 static inline unsigned long
 120 do_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
 121         unsigned long flags, unsigned long fd, unsigned long pgoff)
 122 {
 123         unsigned long error = -EBADF;
 124         struct file * file = NULL;
 125
 126         flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
 127         if (!(flags & MAP_ANONYMOUS)) {
 128                 file = fget(fd);
 129                 if (!file)
 130                         goto out;
 131         }
 132
 133         down_write(&current->mm->mmap_sem);
 134         error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
 135         up_write(&current->mm->mmap_sem);
 136
 137         if (file)
 138                 fput(file);
 139 out:
 140         return error;
 141 }
 142
 143 asmlinkage unsigned long
 144 old_mmap(unsigned long addr, unsigned long len, int prot,
 145         int flags, int fd, off_t offset)
 146 {
 147         unsigned long result;
 148
 149         result = -EINVAL;
 150         if (offset & ~PAGE_MASK)
 151                 goto out;
 152
 153         result = do_mmap2(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
 154
 155 out:
 156         return result;
 157 }
 158
 159 asmlinkage unsigned long
 160 sys_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
 161           unsigned long flags, unsigned long fd, unsigned long pgoff)
 162 {
 163         if (pgoff & (~PAGE_MASK >> 12))
 164                 return -EINVAL;
 165
 166         return do_mmap2(addr, len, prot, flags, fd, pgoff >> (PAGE_SHIFT-12));
 167 }
 168
 169 save_static_function(sys_fork);
 170 static int __used noinline
 171 _sys_fork(nabi_no_regargs struct pt_regs regs)
 172 {
 173         return do_fork(SIGCHLD, regs.regs[29], &regs, 0, NULL, NULL);
 174 }
 175
 176 save_static_function(sys_clone);
 177 static int __used noinline
 178 _sys_clone(nabi_no_regargs struct pt_regs regs)
 179 {
 180         unsigned long clone_flags;
 181         unsigned long newsp;
 182         int __user *parent_tidptr, *child_tidptr;
 183
 184         clone_flags = regs.regs[4];
 185         newsp = regs.regs[5];
 186         if (!newsp)
 187                 newsp = regs.regs[29];
 188         parent_tidptr = (int __user *) regs.regs[6];
 189 #ifdef CONFIG_32BIT
 190         /* We need to fetch the fifth argument off the stack.  */
 191         child_tidptr = NULL;
 192         if (clone_flags & (CLONE_CHILD_SETTID | CLONE_CHILD_CLEARTID)) {
 193                 int __user *__user *usp = (int __user *__user *) regs.regs[29];
 194                 if (regs.regs[2] == __NR_syscall) {
 195                         if (get_user (child_tidptr, &usp[5]))
 196                                 return -EFAULT;
 197                 }
 198                 else if (get_user (child_tidptr, &usp[4]))
 199                         return -EFAULT;
 200         }
 201 #else
 202         child_tidptr = (int __user *) regs.regs[8];
 203 #endif
 204         return do_fork(clone_flags, newsp, &regs, 0,
 205                        parent_tidptr, child_tidptr);
 206 }
 207
 208 /*
 209  * sys_execve() executes a new program.
 210  */
 211 asmlinkage int sys_execve(nabi_no_regargs struct pt_regs regs)
 212 {
 213         int error;
 214         char * filename;
 215
 216         filename = getname((char __user *) (long)regs.regs[4]);
 217         error = PTR_ERR(filename);
 218         if (IS_ERR(filename))
 219                 goto out;
 220         error = do_execve(filename, (char __user *__user *) (long)regs.regs[5],
 221                           (char __user *__user *) (long)regs.regs[6], &regs);
 222         putname(filename);
 223
 224 out:
 225         return error;
 226 }
 227
 228 /*
 229  * Compacrapability ...
 230  */
 231 asmlinkage int sys_uname(struct old_utsname __user * name)
 232 {
 233         if (name && !copy_to_user(name, utsname(), sizeof (*name)))
 234                 return 0;
 235         return -EFAULT;
 236 }
 237
 238 /*
 239  * Compacrapability ...
 240  */
 241 asmlinkage int sys_olduname(struct oldold_utsname __user * name)
 242 {
 243         int error;
 244
 245         if (!name)
 246                 return -EFAULT;
 247         if (!access_ok(VERIFY_WRITE,name,sizeof(struct oldold_utsname)))
 248                 return -EFAULT;
 249
 250         error = __copy_to_user(&name->sysname, &utsname()->sysname,
 251                                __OLD_UTS_LEN);
 252         error -= __put_user(0, name->sysname + __OLD_UTS_LEN);
 253         error -= __copy_to_user(&name->nodename, &utsname()->nodename,
 254                                 __OLD_UTS_LEN);
 255         error -= __put_user(0, name->nodename + __OLD_UTS_LEN);
 256         error -= __copy_to_user(&name->release, &utsname()->release,
 257                                 __OLD_UTS_LEN);
 258         error -= __put_user(0, name->release + __OLD_UTS_LEN);
 259         error -= __copy_to_user(&name->version, &utsname()->version,
 260                                 __OLD_UTS_LEN);
 261         error -= __put_user(0, name->version + __OLD_UTS_LEN);
 262         error -= __copy_to_user(&name->machine, &utsname()->machine,
 263                                 __OLD_UTS_LEN);
 264         error = __put_user(0, name->machine + __OLD_UTS_LEN);
 265         error = error ? -EFAULT : 0;
 266
 267         return error;
 268 }
 269
 270 asmlinkage int sys_set_thread_area(unsigned long addr)
 271 {
 272         struct thread_info *ti = task_thread_info(current);
 273
 274         ti->tp_value = addr;
 275         if (cpu_has_userlocal)
 276                 write_c0_userlocal(addr);
 277
 278         return 0;
 279 }
 280
 281 asmlinkage int _sys_sysmips(int cmd, long arg1, int arg2, int arg3)
 282 {
 283         int     tmp;
 284
 285         switch(cmd) {
 286         case MIPS_ATOMIC_SET:
 287                 printk(KERN_CRIT "How did I get here?\n");
 288                 return -EINVAL;
 289
 290         case MIPS_FIXADE:
 291                 tmp = current->thread.mflags & ~3;
 292                 current->thread.mflags = tmp | (arg1 & 3);
 293                 return 0;
 294
 295         case FLUSH_CACHE:
 296                 __flush_cache_all();
 297                 return 0;
 298         }
 299
 300         return -EINVAL;
 301 }
 302
 303 /*
 304  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
 305  *
 306  * This is really horribly ugly.
 307  */
 308 asmlinkage int sys_ipc (unsigned int call, int first, int second,
 309                         unsigned long third, void __user *ptr, long fifth)
 310 {
 311         int version, ret;
 312
 313         version = call >> 16; /* hack for backward compatibility */
 314         call &= 0xffff;
 315
 316         switch (call) {
 317         case SEMOP:
 318                 return sys_semtimedop (first, (struct sembuf __user *)ptr,
 319                                        second, NULL);
 320         case SEMTIMEDOP:
 321                 return sys_semtimedop (first, (struct sembuf __user *)ptr,
 322                                        second,
 323                                        (const struct timespec __user *)fifth);
 324         case SEMGET:
 325                 return sys_semget (first, second, third);
 326         case SEMCTL: {
 327                 union semun fourth;
 328                 if (!ptr)
 329                         return -EINVAL;
 330                 if (get_user(fourth.__pad, (void __user *__user *) ptr))
 331                         return -EFAULT;
 332                 return sys_semctl (first, second, third, fourth);
 333         }
 334
 335         case MSGSND:
 336                 return sys_msgsnd (first, (struct msgbuf __user *) ptr,
 337                                    second, third);
 338         case MSGRCV:
 339                 switch (version) {
 340                 case 0: {
 341                         struct ipc_kludge tmp;
 342                         if (!ptr)
 343                                 return -EINVAL;
 344
 345                         if (copy_from_user(&tmp,
 346                                            (struct ipc_kludge __user *) ptr,
 347                                            sizeof (tmp)))
 348                                 return -EFAULT;
 349                         return sys_msgrcv (first, tmp.msgp, second,
 350                                            tmp.msgtyp, third);
 351                 }
 352                 default:
 353                         return sys_msgrcv (first,
 354                                            (struct msgbuf __user *) ptr,
 355                                            second, fifth, third);
 356                 }
 357         case MSGGET:
 358                 return sys_msgget ((key_t) first, second);
 359         case MSGCTL:
 360                 return sys_msgctl (first, second,
 361                                    (struct msqid_ds __user *) ptr);
 362
 363         case SHMAT:
 364                 switch (version) {
 365                 default: {
 366                         unsigned long raddr;
 367                         ret = do_shmat (first, (char __user *) ptr, second,
 368                                         &raddr);
 369                         if (ret)
 370                                 return ret;
 371                         return put_user (raddr, (unsigned long __user *) third);
 372                 }
 373                 case 1: /* iBCS2 emulator entry point */
 374                         if (!segment_eq(get_fs(), get_ds()))
 375                                 return -EINVAL;
 376                         return do_shmat (first, (char __user *) ptr, second,
 377                                          (unsigned long *) third);
 378                 }
 379         case SHMDT:
 380                 return sys_shmdt ((char __user *)ptr);
 381         case SHMGET:
 382                 return sys_shmget (first, second, third);
 383         case SHMCTL:
 384                 return sys_shmctl (first, second,
 385                                    (struct shmid_ds __user *) ptr);
 386         default:
 387                 return -ENOSYS;
 388         }
 389 }
 390
 391 /*
 392  * No implemented yet ...
 393  */
 394 asmlinkage int sys_cachectl(char *addr, int nbytes, int op)
 395 {
 396         return -ENOSYS;
 397 }
 398
 399 /*
 400  * If we ever come here the user sp is bad.  Zap the process right away.
 401  * Due to the bad stack signaling wouldn't work.
 402  */
 403 asmlinkage void bad_stack(void)
 404 {
 405         do_exit(SIGSEGV);
 406 }
 407
 408 /*
 409  * Do a system call from kernel instead of calling sys_execve so we
 410  * end up with proper pt_regs.
 411  */
 412 int kernel_execve(const char *filename, char *const argv[], char *const envp[])
 413 {
 414         register unsigned long __a0 asm("$4") = (unsigned long) filename;
 415         register unsigned long __a1 asm("$5") = (unsigned long) argv;
 416         register unsigned long __a2 asm("$6") = (unsigned long) envp;
 417         register unsigned long __a3 asm("$7");
 418         unsigned long __v0;
 419
 420         __asm__ volatile ("                                     \n"
 421         "       .set    noreorder                               \n"
 422         "       li      $2, %5          # __NR_execve           \n"
 423         "       syscall                                         \n"
 424         "       move    %0, $2                                  \n"
 425         "       .set    reorder                                 \n"
 426         : "=&r" (__v0), "=r" (__a3)
 427         : "r" (__a0), "r" (__a1), "r" (__a2), "i" (__NR_execve)
 428         : "$2", "$8", "$9", "$10", "$11", "$12", "$13", "$14", "$15", "$24",
 429           "memory");
 430
 431         if (__a3 == 0)
 432                 return __v0;
 433
 434         return -__v0;
 435 }