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, UPT_SP(&current->thread.regs.regs),
  35                       &current->thread.regs, 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,
  46                       UPT_SP(&current->thread.regs.regs),
  47                       &current->thread.regs, 0, NULL, NULL);
  48         current->thread.forking = 0;
  49         return(ret);
  50 }
  51
  52 /* common code for old and new mmaps */
  53 long sys_mmap2(unsigned long addr, unsigned long len,
  54                unsigned long prot, unsigned long flags,
  55                unsigned long fd, unsigned long pgoff)
  56 {
  57         long error = -EBADF;
  58         struct file * file = NULL;
  59
  60         flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
  61         if (!(flags & MAP_ANONYMOUS)) {
  62                 file = fget(fd);
  63                 if (!file)
  64                         goto out;
  65         }
  66
  67         down_write(&current->mm->mmap_sem);
  68         error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
  69         up_write(&current->mm->mmap_sem);
  70
  71         if (file)
  72                 fput(file);
  73  out:
  74         return error;
  75 }
  76
  77 long old_mmap(unsigned long addr, unsigned long len,
  78               unsigned long prot, unsigned long flags,
  79               unsigned long fd, unsigned long offset)
  80 {
  81         long err = -EINVAL;
  82         if (offset & ~PAGE_MASK)
  83                 goto out;
  84
  85         err = sys_mmap2(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
  86  out:
  87         return err;
  88 }
  89 /*
  90  * sys_pipe() is the normal C calling standard for creating
  91  * a pipe. It's not the way unix traditionally does this, though.
  92  */
  93 long sys_pipe(unsigned long __user * fildes)
  94 {
  95         int fd[2];
  96         long error;
  97
  98         error = do_pipe(fd);
  99         if (!error) {
 100                 if (copy_to_user(fildes, fd, sizeof(fd)))
 101                         error = -EFAULT;
 102         }
 103         return error;
 104 }
 105
 106
 107 long sys_uname(struct old_utsname * name)
 108 {
 109         long err;
 110         if (!name)
 111                 return -EFAULT;
 112         down_read(&uts_sem);
 113         err=copy_to_user(name, &system_utsname, sizeof (*name));
 114         up_read(&uts_sem);
 115         return err?-EFAULT:0;
 116 }
 117
 118 long sys_olduname(struct oldold_utsname * name)
 119 {
 120         long error;
 121
 122         if (!name)
 123                 return -EFAULT;
 124         if (!access_ok(VERIFY_WRITE,name,sizeof(struct oldold_utsname)))
 125                 return -EFAULT;
 126
 127         down_read(&uts_sem);
 128
 129         error = __copy_to_user(&name->sysname,&system_utsname.sysname,
 130                                __OLD_UTS_LEN);
 131         error |= __put_user(0,name->sysname+__OLD_UTS_LEN);
 132         error |= __copy_to_user(&name->nodename,&system_utsname.nodename,
 133                                 __OLD_UTS_LEN);
 134         error |= __put_user(0,name->nodename+__OLD_UTS_LEN);
 135         error |= __copy_to_user(&name->release,&system_utsname.release,
 136                                 __OLD_UTS_LEN);
 137         error |= __put_user(0,name->release+__OLD_UTS_LEN);
 138         error |= __copy_to_user(&name->version,&system_utsname.version,
 139                                 __OLD_UTS_LEN);
 140         error |= __put_user(0,name->version+__OLD_UTS_LEN);
 141         error |= __copy_to_user(&name->machine,&system_utsname.machine,
 142                                 __OLD_UTS_LEN);
 143         error |= __put_user(0,name->machine+__OLD_UTS_LEN);
 144
 145         up_read(&uts_sem);
 146
 147         error = error ? -EFAULT : 0;
 148
 149         return error;
 150 }
 151
 152 DEFINE_SPINLOCK(syscall_lock);
 153
 154 static int syscall_index = 0;
 155
 156 int next_syscall_index(int limit)
 157 {
 158         int ret;
 159
 160         spin_lock(&syscall_lock);
 161         ret = syscall_index;
 162         if(++syscall_index == limit)
 163                 syscall_index = 0;
 164         spin_unlock(&syscall_lock);
 165         return(ret);
 166 }