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 __user * dev_name, char __user * dir_name,
  31               char __user * type, unsigned long new_flags, void __user * data)
  32 {
  33         return(sys_mount(dev_name, dir_name, type, new_flags, data));
  34 }
  35
  36 long sys_fork(void)
  37 {
  38         long ret;
  39
  40         current->thread.forking = 1;
  41         ret = do_fork(SIGCHLD, 0, NULL, 0, NULL, NULL);
  42         current->thread.forking = 0;
  43         return(ret);
  44 }
  45
  46 long sys_vfork(void)
  47 {
  48         long ret;
  49
  50         current->thread.forking = 1;
  51         ret = do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, 0, NULL, 0, NULL,
  52                       NULL);
  53         current->thread.forking = 0;
  54         return(ret);
  55 }
  56
  57 /* common code for old and new mmaps */
  58 long sys_mmap2(unsigned long addr, unsigned long len,
  59                unsigned long prot, unsigned long flags,
  60                unsigned long fd, unsigned long pgoff)
  61 {
  62         long error = -EBADF;
  63         struct file * file = NULL;
  64
  65         flags &= ~(MAP_EXECUTABLE | MAP_DENYWRITE);
  66         if (!(flags & MAP_ANONYMOUS)) {
  67                 file = fget(fd);
  68                 if (!file)
  69                         goto out;
  70         }
  71
  72         down_write(&current->mm->mmap_sem);
  73         error = do_mmap_pgoff(file, addr, len, prot, flags, pgoff);
  74         up_write(&current->mm->mmap_sem);
  75
  76         if (file)
  77                 fput(file);
  78  out:
  79         return error;
  80 }
  81
  82 long old_mmap(unsigned long addr, unsigned long len,
  83               unsigned long prot, unsigned long flags,
  84               unsigned long fd, unsigned long offset)
  85 {
  86         long err = -EINVAL;
  87         if (offset & ~PAGE_MASK)
  88                 goto out;
  89
  90         err = sys_mmap2(addr, len, prot, flags, fd, offset >> PAGE_SHIFT);
  91  out:
  92         return err;
  93 }
  94 /*
  95  * sys_pipe() is the normal C calling standard for creating
  96  * a pipe. It's not the way unix traditionally does this, though.
  97  */
  98 long sys_pipe(unsigned long __user * fildes)
  99 {
 100         int fd[2];
 101         long error;
 102
 103         error = do_pipe(fd);
 104         if (!error) {
 105                 if (copy_to_user(fildes, fd, sizeof(fd)))
 106                         error = -EFAULT;
 107         }
 108         return error;
 109 }
 110
 111
 112 long sys_uname(struct old_utsname * name)
 113 {
 114         long err;
 115         if (!name)
 116                 return -EFAULT;
 117         down_read(&uts_sem);
 118         err=copy_to_user(name, &system_utsname, sizeof (*name));
 119         up_read(&uts_sem);
 120         return err?-EFAULT:0;
 121 }
 122
 123 long sys_olduname(struct oldold_utsname * name)
 124 {
 125         long error;
 126
 127         if (!name)
 128                 return -EFAULT;
 129         if (!access_ok(VERIFY_WRITE,name,sizeof(struct oldold_utsname)))
 130                 return -EFAULT;
 131
 132         down_read(&uts_sem);
 133
 134         error = __copy_to_user(&name->sysname,&system_utsname.sysname,
 135                                __OLD_UTS_LEN);
 136         error |= __put_user(0,name->sysname+__OLD_UTS_LEN);
 137         error |= __copy_to_user(&name->nodename,&system_utsname.nodename,
 138                                 __OLD_UTS_LEN);
 139         error |= __put_user(0,name->nodename+__OLD_UTS_LEN);
 140         error |= __copy_to_user(&name->release,&system_utsname.release,
 141                                 __OLD_UTS_LEN);
 142         error |= __put_user(0,name->release+__OLD_UTS_LEN);
 143         error |= __copy_to_user(&name->version,&system_utsname.version,
 144                                 __OLD_UTS_LEN);
 145         error |= __put_user(0,name->version+__OLD_UTS_LEN);
 146         error |= __copy_to_user(&name->machine,&system_utsname.machine,
 147                                 __OLD_UTS_LEN);
 148         error |= __put_user(0,name->machine+__OLD_UTS_LEN);
 149
 150         up_read(&uts_sem);
 151
 152         error = error ? -EFAULT : 0;
 153
 154         return error;
 155 }
 156
 157 long execute_syscall(void *r)
 158 {
 159         return(CHOOSE_MODE_PROC(execute_syscall_tt, execute_syscall_skas, r));
 160 }
 161
 162 spinlock_t syscall_lock = SPIN_LOCK_UNLOCKED;
 163
 164 static int syscall_index = 0;
 165
 166 int next_syscall_index(int limit)
 167 {
 168         int ret;
 169
 170         spin_lock(&syscall_lock);
 171         ret = syscall_index;
 172         if(++syscall_index == limit)
 173                 syscall_index = 0;
 174         spin_unlock(&syscall_lock);
 175         return(ret);
 176 }
 177
 178 /*
 179  * Overrides for Emacs so that we follow Linus's tabbing style.
 180  * Emacs will notice this stuff at the end of the file and automatically
 181  * adjust the settings for this buffer only.  This must remain at the end
 182  * of the file.
 183  * ---------------------------------------------------------------------------
 184  * Local variables:
 185  * c-file-style: "linux"
 186  * End:
 187  */