arch/um/kernel/syscall_kern.c

   1 /*
   2  * Copyright (C) 2000 Jeff Dike (jdike@karaya.com)
   3  * Licensed under the GPL
   4  */
   5
   6 #include "linux/sched.h"
   7 #include "linux/file.h"
   8 #include "linux/smp_lock.h"
   9 #include "linux/mm.h"
  10 #include "linux/utsname.h"
  11 #include "linux/msg.h"
  12 #include "linux/shm.h"
  13 #include "linux/sys.h"
  14 #include "linux/syscalls.h"
  15 #include "linux/unistd.h"
  16 #include "linux/slab.h"
  17 #include "linux/utime.h"
  18 #include <linux/vs_cvirt.h>
  19
  20 #include "asm/mman.h"
  21 #include "asm/uaccess.h"
  22 #include "asm/ipc.h"
  23 #include "kern_util.h"
  24 #include "user_util.h"
  25 #include "sysdep/syscalls.h"
  26 #include "mode_kern.h"
  27 #include "choose-mode.h"
  28
  29 /*  Unlocked, I don't care if this is a bit off */
  30 int nsyscalls = 0;
  31
  32 long um_mount(char * dev_name, char * dir_name, char * type,
  33               unsigned long new_flags, void * data)
  34 {
  35         if(type == NULL) type = "";
  36         return(sys_mount(dev_name, dir_name, type, new_flags, data));
  37 }
  38
  39 long sys_fork(void)
  40 {
  41         struct task_struct *p;
  42
  43         current->thread.forking = 1;
  44         p = do_fork(SIGCHLD, 0, NULL, 0, NULL, NULL);
  45         current->thread.forking = 0;
  46         return(IS_ERR(p) ? PTR_ERR(p) : p->pid);
  47 }
  48
  49 long sys_clone(unsigned long clone_flags, unsigned long newsp)
  50 {
  51         struct task_struct *p;
  52
  53         current->thread.forking = 1;
  54         p = do_fork(clone_flags, newsp, NULL, 0, NULL, NULL);
  55         current->thread.forking = 0;
  56         return(IS_ERR(p) ? PTR_ERR(p) : p->pid);
  57 }
  58
  59 long sys_vfork(void)
  60 {
  61         struct task_struct *p;
  62
  63         current->thread.forking = 1;
  64         p = do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, 0, NULL, 0, NULL, NULL);
  65         current->thread.forking = 0;
  66         return(IS_ERR(p) ? PTR_ERR(p) : p->pid);
  67 }
  68
  69 /* common code for old and new mmaps */
  70 static inline long do_mmap2(
  71         unsigned long addr, unsigned long len,
  72         unsigned long prot, unsigned long flags,
  73         unsigned long fd, unsigned long pgoff)
  74 {
  75         int error = -EBADF;
  76         struct file * file = NULL;
  77
  78         flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
  79         if (!(flags & MAP_ANONYMOUS)) {
  80                 file = fget(fd);
  81                 if (!file)
  82                         goto out;
  83         }
  84
  85         down_write(&current->mm->mmap_sem);
  86         error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
  87         up_write(&current->mm->mmap_sem);
  88
  89         if (file)
  90                 fput(file);
  91  out:
  92         return error;
  93 }
  94
  95 long sys_mmap2(unsigned long addr, unsigned long len,
  96                unsigned long prot, unsigned long flags,
  97                unsigned long fd, unsigned long pgoff)
  98 {
  99         return do_mmap2(addr, len, prot, flags, fd, pgoff);
 100 }
 101
 102 /*
 103  * Perform the select(nd, in, out, ex, tv) and mmap() system
 104  * calls. Linux/i386 didn't use to be able to handle more than
 105  * 4 system call parameters, so these system calls used a memory
 106  * block for parameter passing..
 107  */
 108
 109 struct mmap_arg_struct {
 110         unsigned long addr;
 111         unsigned long len;
 112         unsigned long prot;
 113         unsigned long flags;
 114         unsigned long fd;
 115         unsigned long offset;
 116 };
 117
 118 int old_mmap(unsigned long addr, unsigned long len,
 119              unsigned long prot, unsigned long flags,
 120              unsigned long fd, unsigned long offset)
 121 {
 122         int err = -EINVAL;
 123         if (offset & ~PAGE_MASK)
 124                 goto out;
 125
 126         err = do_mmap2(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
 127  out:
 128         return err;
 129 }
 130 /*
 131  * sys_pipe() is the normal C calling standard for creating
 132  * a pipe. It's not the way unix traditionally does this, though.
 133  */
 134 int sys_pipe(unsigned long * fildes)
 135 {
 136         int fd[2];
 137         int error;
 138
 139         error = do_pipe(fd);
 140         if (!error) {
 141                 if (copy_to_user(fildes, fd, 2*sizeof(int)))
 142                         error = -EFAULT;
 143         }
 144         return error;
 145 }
 146
 147 int sys_sigaction(int sig, const struct old_sigaction *act,
 148                          struct old_sigaction *oact)
 149 {
 150         struct k_sigaction new_ka, old_ka;
 151         int ret;
 152
 153         if (act) {
 154                 old_sigset_t mask;
 155                 if (verify_area(VERIFY_READ, act, sizeof(*act)) ||
 156                     __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
 157                     __get_user(new_ka.sa.sa_restorer, &act->sa_restorer))
 158                         return -EFAULT;
 159                 __get_user(new_ka.sa.sa_flags, &act->sa_flags);
 160                 __get_user(mask, &act->sa_mask);
 161                 siginitset(&new_ka.sa.sa_mask, mask);
 162         }
 163
 164         ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
 165
 166         if (!ret && oact) {
 167                 if (verify_area(VERIFY_WRITE, oact, sizeof(*oact)) ||
 168                     __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
 169                     __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer))
 170                         return -EFAULT;
 171                 __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
 172                 __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask);
 173         }
 174
 175         return ret;
 176 }
 177
 178 /*
 179  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
 180  *
 181  * This is really horribly ugly.
 182  */
 183 int sys_ipc (uint call, int first, int second,
 184              int third, void *ptr, long fifth)
 185 {
 186         int version, ret;
 187
 188         version = call >> 16; /* hack for backward compatibility */
 189         call &= 0xffff;
 190
 191         switch (call) {
 192         case SEMOP:
 193                 return sys_semtimedop(first, (struct sembuf *) ptr, second,
 194                                       NULL);
 195         case SEMTIMEDOP:
 196                 return sys_semtimedop(first, (struct sembuf *) ptr, second,
 197                                       (const struct timespec *) fifth);
 198         case SEMGET:
 199                 return sys_semget (first, second, third);
 200         case SEMCTL: {
 201                 union semun fourth;
 202                 if (!ptr)
 203                         return -EINVAL;
 204                 if (get_user(fourth.__pad, (void **) ptr))
 205                         return -EFAULT;
 206                 return sys_semctl (first, second, third, fourth);
 207         }
 208
 209         case MSGSND:
 210                 return sys_msgsnd (first, (struct msgbuf *) ptr,
 211                                    second, third);
 212         case MSGRCV:
 213                 switch (version) {
 214                 case 0: {
 215                         struct ipc_kludge tmp;
 216                         if (!ptr)
 217                                 return -EINVAL;
 218
 219                         if (copy_from_user(&tmp,
 220                                            (struct ipc_kludge *) ptr,
 221                                            sizeof (tmp)))
 222                                 return -EFAULT;
 223                         return sys_msgrcv (first, tmp.msgp, second,
 224                                            tmp.msgtyp, third);
 225                 }
 226                 default:
 227                         panic("msgrcv with version != 0");
 228                         return sys_msgrcv (first,
 229                                            (struct msgbuf *) ptr,
 230                                            second, fifth, third);
 231                 }
 232         case MSGGET:
 233                 return sys_msgget ((key_t) first, second);
 234         case MSGCTL:
 235                 return sys_msgctl (first, second, (struct msqid_ds *) ptr);
 236
 237         case SHMAT:
 238                 switch (version) {
 239                 default: {
 240                         ulong raddr;
 241                         ret = do_shmat (first, (char *) ptr, second, &raddr);
 242                         if (ret)
 243                                 return ret;
 244                         return put_user (raddr, (ulong *) third);
 245                 }
 246                 case 1: /* iBCS2 emulator entry point */
 247                         if (!segment_eq(get_fs(), get_ds()))
 248                                 return -EINVAL;
 249                         return do_shmat (first, (char *) ptr, second, (ulong *) third);
 250                 }
 251         case SHMDT:
 252                 return sys_shmdt ((char *)ptr);
 253         case SHMGET:
 254                 return sys_shmget (first, second, third);
 255         case SHMCTL:
 256                 return sys_shmctl (first, second,
 257                                    (struct shmid_ds *) ptr);
 258         default:
 259                 return -EINVAL;
 260         }
 261 }
 262
 263 int sys_uname(struct old_utsname * name)
 264 {
 265         int err;
 266         if (!name)
 267                 return -EFAULT;
 268         down_read(&uts_sem);
 269         err=copy_to_user(name, vx_new_utsname(), sizeof (*name));
 270         up_read(&uts_sem);
 271         return err?-EFAULT:0;
 272 }
 273
 274 int sys_olduname(struct oldold_utsname * name)
 275 {
 276         int error;
 277         struct new_utsname *ptr;
 278
 279         if (!name)
 280                 return -EFAULT;
 281         if (!access_ok(VERIFY_WRITE,name,sizeof(struct oldold_utsname)))
 282                 return -EFAULT;
 283
 284         down_read(&uts_sem);
 285
 286         ptr = vx_new_utsname();
 287         error = __copy_to_user(&name->sysname,ptr->sysname,
 288                                __OLD_UTS_LEN);
 289         error |= __put_user(0,name->sysname+__OLD_UTS_LEN);
 290         error |= __copy_to_user(&name->nodename,ptr->nodename,
 291                                 __OLD_UTS_LEN);
 292         error |= __put_user(0,name->nodename+__OLD_UTS_LEN);
 293         error |= __copy_to_user(&name->release,ptr->release,
 294                                 __OLD_UTS_LEN);
 295         error |= __put_user(0,name->release+__OLD_UTS_LEN);
 296         error |= __copy_to_user(&name->version,ptr->version,
 297                                 __OLD_UTS_LEN);
 298         error |= __put_user(0,name->version+__OLD_UTS_LEN);
 299         error |= __copy_to_user(&name->machine,ptr->machine,
 300                                 __OLD_UTS_LEN);
 301         error |= __put_user(0,name->machine+__OLD_UTS_LEN);
 302
 303         up_read(&uts_sem);
 304
 305         error = error ? -EFAULT : 0;
 306
 307         return error;
 308 }
 309
 310 int sys_sigaltstack(const stack_t *uss, stack_t *uoss)
 311 {
 312         return(do_sigaltstack(uss, uoss, PT_REGS_SP(&current->thread.regs)));
 313 }
 314
 315 long execute_syscall(void *r)
 316 {
 317         return(CHOOSE_MODE_PROC(execute_syscall_tt, execute_syscall_skas, r));
 318 }
 319
 320 spinlock_t syscall_lock = SPIN_LOCK_UNLOCKED;
 321
 322 static int syscall_index = 0;
 323
 324 int next_syscall_index(int limit)
 325 {
 326         int ret;
 327
 328         spin_lock(&syscall_lock);
 329         ret = syscall_index;
 330         if(++syscall_index == limit)
 331                 syscall_index = 0;
 332         spin_unlock(&syscall_lock);
 333         return(ret);
 334 }
 335
 336 /*
 337  * Overrides for Emacs so that we follow Linus's tabbing style.
 338  * Emacs will notice this stuff at the end of the file and automatically
 339  * adjust the settings for this buffer only.  This must remain at the end
 340  * of the file.
 341  * ---------------------------------------------------------------------------
 342  * Local variables:
 343  * c-file-style: "linux"
 344  * End:
 345  */