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 "kern_util.h"
  21 #include "user_util.h"
  22 #include "sysdep/syscalls.h"
  23 #include "mode_kern.h"
  24 #include "choose-mode.h"
  25
  26 /*  Unlocked, I don't care if this is a bit off */
  27 int nsyscalls = 0;
  28
  29 long sys_fork(void)
  30 {
  31         long ret;
  32
  33         current->thread.forking = 1;
  34         ret = do_fork(SIGCHLD, 0, NULL, 0, NULL, NULL);
  35         current->thread.forking = 0;
  36         return(ret);
  37 }
  38
  39 long sys_vfork(void)
  40 {
  41         long ret;
  42
  43         current->thread.forking = 1;
  44         ret = do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, 0, NULL, 0, NULL,
  45                       NULL);
  46         current->thread.forking = 0;
  47         return(ret);
  48 }
  49
  50 /* common code for old and new mmaps */
  51 long sys_mmap2(unsigned long addr, unsigned long len,
  52                unsigned long prot, unsigned long flags,
  53                unsigned long fd, unsigned long pgoff)
  54 {
  55         long error = -EBADF;
  56         struct file * file = NULL;
  57
  58         flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
  59         if (!(flags & MAP_ANONYMOUS)) {
  60                 file = fget(fd);
  61                 if (!file)
  62                         goto out;
  63         }
  64
  65         down_write(&current->mm->mmap_sem);
  66         error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
  67         up_write(&current->mm->mmap_sem);
  68
  69         if (file)
  70                 fput(file);
  71  out:
  72         return error;
  73 }
  74
  75 long old_mmap(unsigned long addr, unsigned long len,
  76               unsigned long prot, unsigned long flags,
  77               unsigned long fd, unsigned long offset)
  78 {
  79         long err = -EINVAL;
  80         if (offset & ~PAGE_MASK)
  81                 goto out;
  82
  83         err = sys_mmap2(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
  84  out:
  85         return err;
  86 }
  87 /*
  88  * sys_pipe() is the normal C calling standard for creating
  89  * a pipe. It's not the way unix traditionally does this, though.
  90  */
  91 long sys_pipe(unsigned long __user * fildes)
  92 {
  93         int fd[2];
  94         long error;
  95
  96         error = do_pipe(fd);
  97         if (!error) {
  98                 if (copy_to_user(fildes, fd, sizeof(fd)))
  99                         error = -EFAULT;
 100         }
 101         return error;
 102 }
 103
 104
 105 long sys_uname(struct old_utsname * name)
 106 {
 107         long err;
 108         if (!name)
 109                 return -EFAULT;
 110         down_read(&uts_sem);
 111         err=copy_to_user(name, &system_utsname, sizeof (*name));
 112         up_read(&uts_sem);
 113         return err?-EFAULT:0;
 114 }
 115
 116 long sys_olduname(struct oldold_utsname * name)
 117 {
 118         long error;
 119
 120         if (!name)
 121                 return -EFAULT;
 122         if (!access_ok(VERIFY_WRITE,name,sizeof(struct oldold_utsname)))
 123                 return -EFAULT;
 124
 125         down_read(&uts_sem);
 126
 127         error = __copy_to_user(&name->sysname,&system_utsname.sysname,
 128                                __OLD_UTS_LEN);
 129         error |= __put_user(0,name->sysname+__OLD_UTS_LEN);
 130         error |= __copy_to_user(&name->nodename,&system_utsname.nodename,
 131                                 __OLD_UTS_LEN);
 132         error |= __put_user(0,name->nodename+__OLD_UTS_LEN);
 133         error |= __copy_to_user(&name->release,&system_utsname.release,
 134                                 __OLD_UTS_LEN);
 135         error |= __put_user(0,name->release+__OLD_UTS_LEN);
 136         error |= __copy_to_user(&name->version,&system_utsname.version,
 137                                 __OLD_UTS_LEN);
 138         error |= __put_user(0,name->version+__OLD_UTS_LEN);
 139         error |= __copy_to_user(&name->machine,&system_utsname.machine,
 140                                 __OLD_UTS_LEN);
 141         error |= __put_user(0,name->machine+__OLD_UTS_LEN);
 142
 143         up_read(&uts_sem);
 144
 145         error = error ? -EFAULT : 0;
 146
 147         return error;
 148 }
 149
 150 DEFINE_SPINLOCK(syscall_lock);
 151
 152 static int syscall_index = 0;
 153
 154 int next_syscall_index(int limit)
 155 {
 156         int ret;
 157
 158         spin_lock(&syscall_lock);
 159         ret = syscall_index;
 160         if(++syscall_index == limit)
 161                 syscall_index = 0;
 162         spin_unlock(&syscall_lock);
 163         return(ret);
 164 }
 165
 166 /*
 167  * Overrides for Emacs so that we follow Linus's tabbing style.
 168  * Emacs will notice this stuff at the end of the file and automatically
 169  * adjust the settings for this buffer only.  This must remain at the end
 170  * of the file.
 171  * ---------------------------------------------------------------------------
 172  * Local variables:
 173  * c-file-style: "linux"
 174  * End:
 175  */