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 sys_fork(void)
  31 {
  32         long ret;
  33
  34         current->thread.forking = 1;
  35         ret = do_fork(SIGCHLD, 0, NULL, 0, NULL, NULL);
  36         current->thread.forking = 0;
  37         return(ret);
  38 }
  39
  40 long sys_vfork(void)
  41 {
  42         long ret;
  43
  44         current->thread.forking = 1;
  45         ret = do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, 0, NULL, 0, NULL,
  46                       NULL);
  47         current->thread.forking = 0;
  48         return(ret);
  49 }
  50
  51 /* common code for old and new mmaps */
  52 long sys_mmap2(unsigned long addr, unsigned long len,
  53                unsigned long prot, unsigned long flags,
  54                unsigned long fd, unsigned long pgoff)
  55 {
  56         long error = -EBADF;
  57         struct file * file = NULL;
  58
  59         flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
  60         if (!(flags & MAP_ANONYMOUS)) {
  61                 file = fget(fd);
  62                 if (!file)
  63                         goto out;
  64         }
  65
  66         down_write(&current->mm->mmap_sem);
  67         error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
  68         up_write(&current->mm->mmap_sem);
  69
  70         if (file)
  71                 fput(file);
  72  out:
  73         return error;
  74 }
  75
  76 long old_mmap(unsigned long addr, unsigned long len,
  77               unsigned long prot, unsigned long flags,
  78               unsigned long fd, unsigned long offset)
  79 {
  80         long err = -EINVAL;
  81         if (offset & ~PAGE_MASK)
  82                 goto out;
  83
  84         err = sys_mmap2(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
  85  out:
  86         return err;
  87 }
  88 /*
  89  * sys_pipe() is the normal C calling standard for creating
  90  * a pipe. It's not the way unix traditionally does this, though.
  91  */
  92 long sys_pipe(unsigned long __user * fildes)
  93 {
  94         int fd[2];
  95         long error;
  96
  97         error = do_pipe(fd);
  98         if (!error) {
  99                 if (copy_to_user(fildes, fd, sizeof(fd)))
 100                         error = -EFAULT;
 101         }
 102         return error;
 103 }
 104
 105
 106 long sys_uname(struct old_utsname * name)
 107 {
 108         long err;
 109         if (!name)
 110                 return -EFAULT;
 111         down_read(&uts_sem);
 112         err=copy_to_user(name, &system_utsname, sizeof (*name));
 113         up_read(&uts_sem);
 114         return err?-EFAULT:0;
 115 }
 116
 117 long sys_olduname(struct oldold_utsname * name)
 118 {
 119         long error;
 120
 121         if (!name)
 122                 return -EFAULT;
 123         if (!access_ok(VERIFY_WRITE,name,sizeof(struct oldold_utsname)))
 124                 return -EFAULT;
 125
 126         down_read(&uts_sem);
 127
 128         error = __copy_to_user(&name->sysname,&system_utsname.sysname,
 129                                __OLD_UTS_LEN);
 130         error |= __put_user(0,name->sysname+__OLD_UTS_LEN);
 131         error |= __copy_to_user(&name->nodename,&system_utsname.nodename,
 132                                 __OLD_UTS_LEN);
 133         error |= __put_user(0,name->nodename+__OLD_UTS_LEN);
 134         error |= __copy_to_user(&name->release,&system_utsname.release,
 135                                 __OLD_UTS_LEN);
 136         error |= __put_user(0,name->release+__OLD_UTS_LEN);
 137         error |= __copy_to_user(&name->version,&system_utsname.version,
 138                                 __OLD_UTS_LEN);
 139         error |= __put_user(0,name->version+__OLD_UTS_LEN);
 140         error |= __copy_to_user(&name->machine,&system_utsname.machine,
 141                                 __OLD_UTS_LEN);
 142         error |= __put_user(0,name->machine+__OLD_UTS_LEN);
 143
 144         up_read(&uts_sem);
 145
 146         error = error ? -EFAULT : 0;
 147
 148         return error;
 149 }
 150
 151 DEFINE_SPINLOCK(syscall_lock);
 152
 153 static int syscall_index = 0;
 154
 155 int next_syscall_index(int limit)
 156 {
 157         int ret;
 158
 159         spin_lock(&syscall_lock);
 160         ret = syscall_index;
 161         if(++syscall_index == limit)
 162                 syscall_index = 0;
 163         spin_unlock(&syscall_lock);
 164         return(ret);
 165 }
 166
 167 /*
 168  * Overrides for Emacs so that we follow Linus's tabbing style.
 169  * Emacs will notice this stuff at the end of the file and automatically
 170  * adjust the settings for this buffer only.  This must remain at the end
 171  * of the file.
 172  * ---------------------------------------------------------------------------
 173  * Local variables:
 174  * c-file-style: "linux"
 175  * End:
 176  */