release/src-rt/linux/linux-2.6/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 unsigned char shm_align_shift = PAGE_SHIFT;     /* Sane caches */
  60
  61 EXPORT_SYMBOL(shm_align_mask);
  62 EXPORT_SYMBOL(shm_align_shift);
  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 #ifdef CONFIG_32BIT
  76         task_size = TASK_SIZE;
  77 #else /* Must be CONFIG_64BIT*/
  78         task_size = test_thread_flag(TIF_32BIT_ADDR) ? TASK_SIZE32 : TASK_SIZE;
  79 #endif
  80
  81         if (len > task_size)
  82                 return -ENOMEM;
  83
  84         if (flags & MAP_FIXED) {
  85                 /* Even MAP_FIXED mappings must reside within task_size.  */
  86                 if (task_size - len < addr)
  87                         return -EINVAL;
  88
  89                 /*
  90                  * We do not accept a shared mapping if it would violate
  91                  * cache aliasing constraints.
  92                  */
  93                 if ((flags & MAP_SHARED) &&
  94                     ((addr - (pgoff << PAGE_SHIFT)) & shm_align_mask))
  95                         return -EINVAL;
  96                 return addr;
  97         }
  98
  99         do_color_align = 0;
 100         if (filp || (flags & MAP_SHARED))
 101                 do_color_align = 1;
 102         if (addr) {
 103                 if (do_color_align)
 104                         addr = COLOUR_ALIGN(addr, pgoff);
 105                 else
 106                         addr = PAGE_ALIGN(addr);
 107                 vmm = find_vma(current->mm, addr);
 108                 if (task_size - len >= addr &&
 109                     (!vmm || addr + len <= vmm->vm_start))
 110                         return addr;
 111         }
 112         addr = TASK_UNMAPPED_BASE;
 113         if (do_color_align)
 114                 addr = COLOUR_ALIGN(addr, pgoff);
 115         else
 116                 addr = PAGE_ALIGN(addr);
 117
 118         for (vmm = find_vma(current->mm, addr); ; vmm = vmm->vm_next) {
 119                 /* At this point:  (!vmm || addr < vmm->vm_end). */
 120                 if (task_size - len < addr)
 121                         return -ENOMEM;
 122                 if (!vmm || addr + len <= vmm->vm_start)
 123                         return addr;
 124                 addr = vmm->vm_end;
 125                 if (do_color_align)
 126                         addr = COLOUR_ALIGN(addr, pgoff);
 127         }
 128 }
 129
 130 /* common code for old and new mmaps */
 131 static inline unsigned long
 132 do_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
 133         unsigned long flags, unsigned long fd, unsigned long pgoff)
 134 {
 135         unsigned long error = -EBADF;
 136         struct file * file = NULL;
 137
 138         flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
 139         if (!(flags & MAP_ANONYMOUS)) {
 140                 file = fget(fd);
 141                 if (!file)
 142                         goto out;
 143         }
 144
 145         down_write(&current->mm->mmap_sem);
 146         error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
 147         up_write(&current->mm->mmap_sem);
 148
 149         if (file)
 150                 fput(file);
 151 out:
 152         return error;
 153 }
 154
 155 asmlinkage unsigned long
 156 old_mmap(unsigned long addr, unsigned long len, int prot,
 157         int flags, int fd, off_t offset)
 158 {
 159         unsigned long result;
 160
 161         result = -EINVAL;
 162         if (offset & ~PAGE_MASK)
 163                 goto out;
 164
 165         result = do_mmap2(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
 166
 167 out:
 168         return result;
 169 }
 170
 171 asmlinkage unsigned long
 172 sys_mmap2(unsigned long addr, unsigned long len, unsigned long prot,
 173           unsigned long flags, unsigned long fd, unsigned long pgoff)
 174 {
 175         if (pgoff & (~PAGE_MASK >> 12))
 176                 return -EINVAL;
 177
 178         return do_mmap2(addr, len, prot, flags, fd, pgoff >> (PAGE_SHIFT-12));
 179 }
 180
 181 save_static_function(sys_fork);
 182 __attribute_used__ noinline static int
 183 _sys_fork(nabi_no_regargs struct pt_regs regs)
 184 {
 185         return do_fork(SIGCHLD, regs.regs[29], &regs, 0, NULL, NULL);
 186 }
 187
 188 save_static_function(sys_clone);
 189 __attribute_used__ noinline static int
 190 _sys_clone(nabi_no_regargs struct pt_regs regs)
 191 {
 192         unsigned long clone_flags;
 193         unsigned long newsp;
 194         int __user *parent_tidptr, *child_tidptr;
 195
 196         clone_flags = regs.regs[4];
 197         newsp = regs.regs[5];
 198         if (!newsp)
 199                 newsp = regs.regs[29];
 200         parent_tidptr = (int __user *) regs.regs[6];
 201 #ifdef CONFIG_32BIT
 202         /* We need to fetch the fifth argument off the stack.  */
 203         child_tidptr = NULL;
 204         if (clone_flags & (CLONE_CHILD_SETTID | CLONE_CHILD_CLEARTID)) {
 205                 int __user *__user *usp = (int __user *__user *) regs.regs[29];
 206                 if (regs.regs[2] == __NR_syscall) {
 207                         if (get_user (child_tidptr, &usp[5]))
 208                                 return -EFAULT;
 209                 }
 210                 else if (get_user (child_tidptr, &usp[4]))
 211                         return -EFAULT;
 212         }
 213 #else
 214         child_tidptr = (int __user *) regs.regs[8];
 215 #endif
 216         return do_fork(clone_flags, newsp, &regs, 0,
 217                        parent_tidptr, child_tidptr);
 218 }
 219
 220 /*
 221  * sys_execve() executes a new program.
 222  */
 223 asmlinkage int sys_execve(nabi_no_regargs struct pt_regs regs)
 224 {
 225         int error;
 226         char * filename;
 227
 228         filename = getname((char __user *) (long)regs.regs[4]);
 229         error = PTR_ERR(filename);
 230         if (IS_ERR(filename))
 231                 goto out;
 232         error = do_execve(filename, (char __user *__user *) (long)regs.regs[5],
 233                           (char __user *__user *) (long)regs.regs[6], &regs);
 234         putname(filename);
 235
 236 out:
 237         return error;
 238 }
 239
 240 /*
 241  * Compacrapability ...
 242  */
 243 asmlinkage int sys_uname(struct old_utsname __user * name)
 244 {
 245         if (name && !copy_to_user(name, utsname(), sizeof (*name)))
 246                 return 0;
 247         return -EFAULT;
 248 }
 249
 250 /*
 251  * Compacrapability ...
 252  */
 253 asmlinkage int sys_olduname(struct oldold_utsname __user * name)
 254 {
 255         int error;
 256
 257         if (!name)
 258                 return -EFAULT;
 259         if (!access_ok(VERIFY_WRITE,name,sizeof(struct oldold_utsname)))
 260                 return -EFAULT;
 261
 262         error = __copy_to_user(&name->sysname, &utsname()->sysname,
 263                                __OLD_UTS_LEN);
 264         error -= __put_user(0, name->sysname + __OLD_UTS_LEN);
 265         error -= __copy_to_user(&name->nodename, &utsname()->nodename,
 266                                 __OLD_UTS_LEN);
 267         error -= __put_user(0, name->nodename + __OLD_UTS_LEN);
 268         error -= __copy_to_user(&name->release, &utsname()->release,
 269                                 __OLD_UTS_LEN);
 270         error -= __put_user(0, name->release + __OLD_UTS_LEN);
 271         error -= __copy_to_user(&name->version, &utsname()->version,
 272                                 __OLD_UTS_LEN);
 273         error -= __put_user(0, name->version + __OLD_UTS_LEN);
 274         error -= __copy_to_user(&name->machine, &utsname()->machine,
 275                                 __OLD_UTS_LEN);
 276         error = __put_user(0, name->machine + __OLD_UTS_LEN);
 277         error = error ? -EFAULT : 0;
 278
 279         return error;
 280 }
 281
 282 asmlinkage int sys_set_thread_area(unsigned long addr)
 283 {
 284         struct thread_info *ti = task_thread_info(current);
 285
 286         ti->tp_value = addr;
 287         if (cpu_has_userlocal)
 288                 write_c0_userlocal(addr);
 289
 290         return 0;
 291 }
 292
 293 asmlinkage int _sys_sysmips(int cmd, long arg1, int arg2, int arg3)
 294 {
 295         int     tmp;
 296
 297         switch(cmd) {
 298         case MIPS_ATOMIC_SET:
 299                 printk(KERN_CRIT "How did I get here?\n");
 300                 return -EINVAL;
 301
 302         case MIPS_FIXADE:
 303                 tmp = current->thread.mflags & ~3;
 304                 current->thread.mflags = tmp | (arg1 & 3);
 305                 return 0;
 306
 307         case FLUSH_CACHE:
 308                 __flush_cache_all();
 309                 return 0;
 310         }
 311
 312         return -EINVAL;
 313 }
 314
 315 /*
 316  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
 317  *
 318  * This is really horribly ugly.
 319  */
 320 asmlinkage int sys_ipc (unsigned int call, int first, int second,
 321                         unsigned long third, void __user *ptr, long fifth)
 322 {
 323         int version, ret;
 324
 325         version = call >> 16; /* hack for backward compatibility */
 326         call &= 0xffff;
 327
 328         switch (call) {
 329         case SEMOP:
 330                 return sys_semtimedop (first, (struct sembuf __user *)ptr,
 331                                        second, NULL);
 332         case SEMTIMEDOP:
 333                 return sys_semtimedop (first, (struct sembuf __user *)ptr,
 334                                        second,
 335                                        (const struct timespec __user *)fifth);
 336         case SEMGET:
 337                 return sys_semget (first, second, third);
 338         case SEMCTL: {
 339                 union semun fourth;
 340                 if (!ptr)
 341                         return -EINVAL;
 342                 if (get_user(fourth.__pad, (void __user *__user *) ptr))
 343                         return -EFAULT;
 344                 return sys_semctl (first, second, third, fourth);
 345         }
 346
 347         case MSGSND:
 348                 return sys_msgsnd (first, (struct msgbuf __user *) ptr,
 349                                    second, third);
 350         case MSGRCV:
 351                 switch (version) {
 352                 case 0: {
 353                         struct ipc_kludge tmp;
 354                         if (!ptr)
 355                                 return -EINVAL;
 356
 357                         if (copy_from_user(&tmp,
 358                                            (struct ipc_kludge __user *) ptr,
 359                                            sizeof (tmp)))
 360                                 return -EFAULT;
 361                         return sys_msgrcv (first, tmp.msgp, second,
 362                                            tmp.msgtyp, third);
 363                 }
 364                 default:
 365                         return sys_msgrcv (first,
 366                                            (struct msgbuf __user *) ptr,
 367                                            second, fifth, third);
 368                 }
 369         case MSGGET:
 370                 return sys_msgget ((key_t) first, second);
 371         case MSGCTL:
 372                 return sys_msgctl (first, second,
 373                                    (struct msqid_ds __user *) ptr);
 374
 375         case SHMAT:
 376                 switch (version) {
 377                 default: {
 378                         unsigned long raddr;
 379                         ret = do_shmat (first, (char __user *) ptr, second,
 380                                         &raddr);
 381                         if (ret)
 382                                 return ret;
 383                         return put_user (raddr, (unsigned long __user *) third);
 384                 }
 385                 case 1: /* iBCS2 emulator entry point */
 386                         if (!segment_eq(get_fs(), get_ds()))
 387                                 return -EINVAL;
 388                         return do_shmat (first, (char __user *) ptr, second,
 389                                          (unsigned long *) third);
 390                 }
 391         case SHMDT:
 392                 return sys_shmdt ((char __user *)ptr);
 393         case SHMGET:
 394                 return sys_shmget (first, second, third);
 395         case SHMCTL:
 396                 return sys_shmctl (first, second,
 397                                    (struct shmid_ds __user *) ptr);
 398         default:
 399                 return -ENOSYS;
 400         }
 401 }
 402
 403 /*
 404  * No implemented yet ...
 405  */
 406 asmlinkage int sys_cachectl(char *addr, int nbytes, int op)
 407 {
 408         return -ENOSYS;
 409 }
 410
 411 /*
 412  * If we ever come here the user sp is bad.  Zap the process right away.
 413  * Due to the bad stack signaling wouldn't work.
 414  */
 415 asmlinkage void bad_stack(void)
 416 {
 417         do_exit(SIGSEGV);
 418 }
 419
 420 /*
 421  * Do a system call from kernel instead of calling sys_execve so we
 422  * end up with proper pt_regs.
 423  */
 424 int kernel_execve(const char *filename, char *const argv[], char *const envp[])
 425 {
 426         register unsigned long __a0 asm("$4") = (unsigned long) filename;
 427         register unsigned long __a1 asm("$5") = (unsigned long) argv;
 428         register unsigned long __a2 asm("$6") = (unsigned long) envp;
 429         register unsigned long __a3 asm("$7");
 430         unsigned long __v0;
 431
 432         __asm__ volatile ("                                     \n"
 433         "       .set    noreorder                               \n"
 434         "       li      $2, %5          # __NR_execve           \n"
 435         "       syscall                                         \n"
 436         "       move    %0, $2                                  \n"
 437         "       .set    reorder                                 \n"
 438         : "=&r" (__v0), "=r" (__a3)
 439         : "r" (__a0), "r" (__a1), "r" (__a2), "i" (__NR_execve)
 440         : "$2", "$8", "$9", "$10", "$11", "$12", "$13", "$14", "$15", "$24",
 441           "memory");
 442
 443         if (__a3 == 0)
 444                 return __v0;
 445
 446         return -__v0;
 447 }
 448
 449 /*
 450  * Build the string table for the builtin "poor man's strace".
 451  */
 452 #ifdef CONFIG_PRINT_SYSCALLS
 453 #define SYS(fun, narg) #fun,
 454 static char *sfnames[] = {
 455 #include "syscalls.h"
 456 };
 457
 458 #ifdef  CONFIG_HWSIM
 459 int do_strace = 1;
 460 #else
 461 int do_strace = 0;
 462 #endif
 463
 464 asmlinkage void strace(struct pt_regs *regs)
 465 {
 466         int i;
 467         unsigned long scn, narg, *pa0;
 468         char *name, space[16];
 469         extern char sys_call_table[];
 470
 471         if (do_strace == 0)
 472                 return;
 473
 474         scn = regs->regs[2];
 475         pa0 = &regs->regs[4];
 476
 477         if ((scn >= __NR_Linux)  && (scn < (__NR_Linux + __NR_Linux_syscalls))) {
 478                 name = sfnames[scn - __NR_Linux];
 479                 narg = *(unsigned long *)(((char *)(&sys_call_table[scn])) + 4);
 480         } else {
 481                 sprintf(space, "sc%lu", scn);
 482                 name = space;
 483                 narg = 0;
 484         }
 485
 486         printk("%lu[%s:%d]@0x%08lx: %s(", jiffies, current->comm, current->pid, regs->cp0_epc, name);
 487
 488         if (narg > 6) narg = 6;
 489
 490         for (i = 0; i < narg; i++) {
 491                 if (i) printk(", ");
 492                 if (i < 4)
 493                         printk("0x%08lx", pa0[i]);
 494                 else
 495                         printk("0x%08lx", regs->pad0[i]);
 496         }
 497
 498         printk(")\n");
 499 }
 500 #endif