sys/vm/vm_vmspace.c

   1 /*
   2  * Copyright (c) 2006 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Matthew Dillon <dillon@backplane.com>
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  *
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in
  15  *    the documentation and/or other materials provided with the
  16  *    distribution.
  17  * 3. Neither the name of The DragonFly Project nor the names of its
  18  *    contributors may be used to endorse or promote products derived
  19  *    from this software without specific, prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  32  * SUCH DAMAGE.
  33  *
  34  * $DragonFly: src/sys/vm/vm_vmspace.c,v 1.1 2006/09/03 17:11:51 dillon Exp $
  35  */
  36
  37 #include <sys/param.h>
  38 #include <sys/kernel.h>
  39 #include <sys/systm.h>
  40 #include <sys/sysproto.h>
  41
  42 /*
  43  * vmspace_ctl {void *id, void *ctx, int what }
  44  *
  45  * Create, destroy, or execute a VM space.  This functions returns when
  46  * the VM space has run for a specified period of time, a signal occurs,
  47  * or the VM space traps or makes a system call.
  48  *
  49  * Execution of a VM space is accomplished by swapping out the caller's
  50  * current VM space.  Any signal or condition applicable to the caller
  51  * will swap the caller's VM space back in for processing, then return
  52  * EINTR.  A trap, system call, or page fault in the VM space will swap
  53  * the caller's VM space back in, adjust the context, and return the
  54  * appropriate code.
  55  *
  56  * A virtual kernel manages multiple 'process' VM spaces this way, the
  57  * real kernel only sees only the processes representing the virtual kernel
  58  * itself, typically one per virtual cpu.
  59  */
  60 int
  61 sys_vmspace_ctl(struct vmspace_ctl_args *uap)
  62 {
  63         return (EINVAL);
  64 }
  65
  66 /*
  67  * vmspace_map { void *id, off_t offset, void *ptr, int bytes, int prot }
  68  *
  69  * Map pages backing the specified memory in the caller's context into
  70  * the specified VM space and reduce their protection using 'prot'.  A
  71  * protection value of 0 removes the page mapping.  Page mappings can be
  72  * removed by the kernel at any time and cause execution of the VM space
  73  * to return with VMSPACE_PAGEFAULT.
  74  */
  75 int
  76 sys_vmspace_map(struct vmspace_map_args *uap)
  77 {
  78         return (EINVAL);
  79 }
  80
  81 /*
  82  * vmspace_protect { void *id, off_t offset, int bytes, int prot }
  83  *
  84  * Adjust the protection of mapped pages in the specified VM context.  Pages
  85  * that are not mapped or whos mapping was removed by the kernel are not
  86  * effected.
  87  */
  88 int
  89 sys_vmspace_protect(struct vmspace_protect_args *uap)
  90 {
  91         return (EINVAL);
  92 }
  93
  94 /*
  95  * vmspace_read { void *id, void *ptr, int bytes }
  96  *
  97  * Read data from the VM space.  Only data in mapped pages can be read.  If
  98  * an unmapped page is encountered this function will return fewer then the
  99  * requested number of bytes and the caller must map the additional pages
 100  * before restarting the call.
 101  */
 102 int
 103 sys_vmspace_read(struct vmspace_read_args *uap)
 104 {
 105         return (EINVAL);
 106 }
 107
 108 /*
 109  * vmspace_write { void *id, const void *ptr, int bytes }
 110  *
 111  * Write data to the VM space.  Only mapped, writable pages can be written.
 112  * If an unmapped or read-only page is encountered this function will return
 113  * fewer then the requested number of bytes and the caller must map the
 114  * additional pages before restarting the call.
 115  */
 116 int
 117 sys_vmspace_write(struct vmspace_write_args *uap)
 118 {
 119         return (EINVAL);
 120 }
 121