arch/um/kernel/syscall_kern.c

   1 /*
   2  * Copyright (C) 2000 - 2003 Jeff Dike (jdike@addtoit.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 "asm/mman.h"
  19 #include "asm/uaccess.h"
  20 #include "asm/ipc.h"
  21 #include "kern_util.h"
  22 #include "user_util.h"
  23 #include "sysdep/syscalls.h"
  24 #include "mode_kern.h"
  25 #include "choose-mode.h"
  26
  27 /*  Unlocked, I don't care if this is a bit off */
  28 int nsyscalls = 0;
  29
  30 long um_mount(char * dev_name, char * dir_name, char * type,
  31               unsigned long new_flags, void * data)
  32 {
  33         if(type == NULL) type = "";
  34         return(sys_mount(dev_name, dir_name, type, new_flags, data));
  35 }
  36
  37 long sys_fork(void)
  38 {
  39         long ret;
  40
  41         current->thread.forking = 1;
  42         ret = do_fork(SIGCHLD, 0, NULL, 0, NULL, NULL);
  43         current->thread.forking = 0;
  44         return(ret);
  45 }
  46
  47 long sys_clone(unsigned long clone_flags, unsigned long newsp,
  48                int *parent_tid, int *child_tid)
  49 {
  50         long ret;
  51
  52         current->thread.forking = 1;
  53         ret = do_fork(clone_flags, newsp, NULL, 0, parent_tid, child_tid);
  54         current->thread.forking = 0;
  55         return(ret);
  56 }
  57
  58 long sys_vfork(void)
  59 {
  60         long ret;
  61
  62         current->thread.forking = 1;
  63         ret = do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, 0, NULL, 0, NULL,
  64                       NULL);
  65         current->thread.forking = 0;
  66         return(ret);
  67 }
  68
  69 /* common code for old and new mmaps */
  70 long do_mmap2(struct mm_struct *mm, unsigned long addr, unsigned long len,
  71               unsigned long prot, unsigned long flags, unsigned long fd,
  72               unsigned long pgoff)
  73 {
  74         int error = -EBADF;
  75         struct file * file = NULL;
  76
  77         flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
  78         if (!(flags & MAP_ANONYMOUS)) {
  79                 file = fget(fd);
  80                 if (!file)
  81                         goto out;
  82         }
  83
  84         down_write(&mm->mmap_sem);
  85         error = do_mmap_pgoff(mm, file, addr, len, prot, flags, pgoff);
  86         up_write(&mm->mmap_sem);
  87
  88         if (file)
  89                 fput(file);
  90  out:
  91         return error;
  92 }
  93
  94 long sys_mmap2(unsigned long addr, unsigned long len,
  95                unsigned long prot, unsigned long flags,
  96                unsigned long fd, unsigned long pgoff)
  97 {
  98         return do_mmap2(current->mm, addr, len, prot, flags, fd, pgoff);
  99 }
 100
 101 /*
 102  * Perform the select(nd, in, out, ex, tv) and mmap() system
 103  * calls. Linux/i386 didn't use to be able to handle more than
 104  * 4 system call parameters, so these system calls used a memory
 105  * block for parameter passing..
 106  */
 107
 108 struct mmap_arg_struct {
 109         unsigned long addr;
 110         unsigned long len;
 111         unsigned long prot;
 112         unsigned long flags;
 113         unsigned long fd;
 114         unsigned long offset;
 115 };
 116
 117 int old_mmap(unsigned long addr, unsigned long len,
 118              unsigned long prot, unsigned long flags,
 119              unsigned long fd, unsigned long offset)
 120 {
 121         int err = -EINVAL;
 122         if (offset & ~PAGE_MASK)
 123                 goto out;
 124
 125         err = do_mmap2(current->mm, addr, len, prot, flags, fd,
 126                        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, sizeof(fd)))
 142                         error = -EFAULT;
 143         }
 144         return error;
 145 }
 146
 147 /*
 148  * sys_ipc() is the de-multiplexer for the SysV IPC calls..
 149  *
 150  * This is really horribly ugly.
 151  */
 152 int sys_ipc (uint call, int first, int second,
 153              int third, void *ptr, long fifth)
 154 {
 155         int version, ret;
 156
 157         version = call >> 16; /* hack for backward compatibility */
 158         call &= 0xffff;
 159
 160         switch (call) {
 161         case SEMOP:
 162                 return sys_semtimedop(first, (struct sembuf *) ptr, second,
 163                                       NULL);
 164         case SEMTIMEDOP:
 165                 return sys_semtimedop(first, (struct sembuf *) ptr, second,
 166                                       (const struct timespec *) fifth);
 167         case SEMGET:
 168                 return sys_semget (first, second, third);
 169         case SEMCTL: {
 170                 union semun fourth;
 171                 if (!ptr)
 172                         return -EINVAL;
 173                 if (get_user(fourth.__pad, (void **) ptr))
 174                         return -EFAULT;
 175                 return sys_semctl (first, second, third, fourth);
 176         }
 177
 178         case MSGSND:
 179                 return sys_msgsnd (first, (struct msgbuf *) ptr,
 180                                    second, third);
 181         case MSGRCV:
 182                 switch (version) {
 183                 case 0: {
 184                         struct ipc_kludge tmp;
 185                         if (!ptr)
 186                                 return -EINVAL;
 187
 188                         if (copy_from_user(&tmp,
 189                                            (struct ipc_kludge *) ptr,
 190                                            sizeof (tmp)))
 191                                 return -EFAULT;
 192                         return sys_msgrcv (first, tmp.msgp, second,
 193                                            tmp.msgtyp, third);
 194                 }
 195                 default:
 196                         panic("msgrcv with version != 0");
 197                         return sys_msgrcv (first,
 198                                            (struct msgbuf *) ptr,
 199                                            second, fifth, third);
 200                 }
 201         case MSGGET:
 202                 return sys_msgget ((key_t) first, second);
 203         case MSGCTL:
 204                 return sys_msgctl (first, second, (struct msqid_ds *) ptr);
 205
 206         case SHMAT:
 207                 switch (version) {
 208                 default: {
 209                         ulong raddr;
 210                         ret = do_shmat (first, (char *) ptr, second, &raddr);
 211                         if (ret)
 212                                 return ret;
 213                         return put_user (raddr, (ulong *) third);
 214                 }
 215                 case 1: /* iBCS2 emulator entry point */
 216                         if (!segment_eq(get_fs(), get_ds()))
 217                                 return -EINVAL;
 218                         return do_shmat (first, (char *) ptr, second, (ulong *) third);
 219                 }
 220         case SHMDT:
 221                 return sys_shmdt ((char *)ptr);
 222         case SHMGET:
 223                 return sys_shmget (first, second, third);
 224         case SHMCTL:
 225                 return sys_shmctl (first, second,
 226                                    (struct shmid_ds *) ptr);
 227         default:
 228                 return -ENOSYS;
 229         }
 230 }
 231
 232 int sys_uname(struct old_utsname * name)
 233 {
 234         int err;
 235         if (!name)
 236                 return -EFAULT;
 237         down_read(&uts_sem);
 238         err=copy_to_user(name, vx_new_utsname(), sizeof (*name));
 239         up_read(&uts_sem);
 240         return err?-EFAULT:0;
 241 }
 242
 243 int sys_olduname(struct oldold_utsname * name)
 244 {
 245         int error;
 246         struct new_utsname *ptr;
 247
 248         if (!name)
 249                 return -EFAULT;
 250         if (!access_ok(VERIFY_WRITE,name,sizeof(struct oldold_utsname)))
 251                 return -EFAULT;
 252
 253         down_read(&uts_sem);
 254
 255         ptr = vx_new_utsname();
 256         error = __copy_to_user(&name->sysname,ptr->sysname,
 257                                __OLD_UTS_LEN);
 258         error |= __put_user(0,name->sysname+__OLD_UTS_LEN);
 259         error |= __copy_to_user(&name->nodename,ptr->nodename,
 260                                 __OLD_UTS_LEN);
 261         error |= __put_user(0,name->nodename+__OLD_UTS_LEN);
 262         error |= __copy_to_user(&name->release,ptr->release,
 263                                 __OLD_UTS_LEN);
 264         error |= __put_user(0,name->release+__OLD_UTS_LEN);
 265         error |= __copy_to_user(&name->version,ptr->version,
 266                                 __OLD_UTS_LEN);
 267         error |= __put_user(0,name->version+__OLD_UTS_LEN);
 268         error |= __copy_to_user(&name->machine,ptr->machine,
 269                                 __OLD_UTS_LEN);
 270         error |= __put_user(0,name->machine+__OLD_UTS_LEN);
 271
 272         up_read(&uts_sem);
 273
 274         error = error ? -EFAULT : 0;
 275
 276         return error;
 277 }
 278
 279 long execute_syscall(void *r)
 280 {
 281         return(CHOOSE_MODE_PROC(execute_syscall_tt, execute_syscall_skas, r));
 282 }
 283
 284 spinlock_t syscall_lock = SPIN_LOCK_UNLOCKED;
 285
 286 static int syscall_index = 0;
 287
 288 int next_syscall_index(int limit)
 289 {
 290         int ret;
 291
 292         spin_lock(&syscall_lock);
 293         ret = syscall_index;
 294         if(++syscall_index == limit)
 295                 syscall_index = 0;
 296         spin_unlock(&syscall_lock);
 297         return(ret);
 298 }
 299
 300 /*
 301  * Overrides for Emacs so that we follow Linus's tabbing style.
 302  * Emacs will notice this stuff at the end of the file and automatically
 303  * adjust the settings for this buffer only.  This must remain at the end
 304  * of the file.
 305  * ---------------------------------------------------------------------------
 306  * Local variables:
 307  * c-file-style: "linux"
 308  * End:
 309  */