sys/kern/subr_kobj_vfs.c

   1 /*      $NetBSD: subr_kobj.c,v 1.39 2009/06/17 21:04:25 dyoung Exp $    */
   2
   3 /*-
   4  * Copyright (c) 2008 The NetBSD Foundation, Inc.
   5  * All rights reserved.
   6  *
   7  * This code is derived from software developed for The NetBSD Foundation
   8  * by Andrew Doran.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
  20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
  23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  29  * POSSIBILITY OF SUCH DAMAGE.
  30  */
  31
  32 /*-
  33  * Copyright (c) 1998-2000 Doug Rabson
  34  * Copyright (c) 2004 Peter Wemm
  35  * All rights reserved.
  36  *
  37  * Redistribution and use in source and binary forms, with or without
  38  * modification, are permitted provided that the following conditions
  39  * are met:
  40  * 1. Redistributions of source code must retain the above copyright
  41  *    notice, this list of conditions and the following disclaimer.
  42  * 2. Redistributions in binary form must reproduce the above copyright
  43  *    notice, this list of conditions and the following disclaimer in the
  44  *    documentation and/or other materials provided with the distribution.
  45  *
  46  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  47  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  48  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  49  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  50  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  51  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  52  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  53  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  54  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  55  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  56  * SUCH DAMAGE.
  57  */
  58
  59 /*
  60  * Kernel loader vfs routines.
  61  */
  62
  63 #include <sys/kobj_impl.h>
  64 #include "opt_modular.h"
  65
  66 #ifdef MODULAR
  67
  68 #include <sys/param.h>
  69 #include <sys/fcntl.h>
  70 #include <sys/module.h>
  71 #include <sys/namei.h>
  72 #include <sys/vnode.h>
  73
  74 #include <sys/cdefs.h>
  75 __KERNEL_RCSID(0, "$NetBSD: subr_kobj.c,v 1.39 2009/06/17 21:04:25 dyoung Exp $");
  76
  77 static void
  78 kobj_close_file(kobj_t ko)
  79 {
  80
  81         VOP_UNLOCK(ko->ko_source, 0);
  82         vn_close(ko->ko_source, FREAD, kauth_cred_get());
  83 }
  84
  85 /*
  86  * kobj_read:
  87  *
  88  *      Utility function: read from the object.
  89  */
  90 static int
  91 kobj_read_file(kobj_t ko, void **basep, size_t size, off_t off,
  92         bool allocate)
  93 {
  94         size_t resid;
  95         void *base;
  96         int error;
  97
  98         KASSERT(ko->ko_source != NULL);
  99
 100         if (allocate) {
 101                 base = kmem_alloc(size, KM_SLEEP);
 102         } else {
 103                 base = *basep;
 104                 KASSERT((uintptr_t)base >= (uintptr_t)ko->ko_address);
 105                 KASSERT((uintptr_t)base + size <=
 106                     (uintptr_t)ko->ko_address + ko->ko_size);
 107         }
 108
 109         error = vn_rdwr(UIO_READ, ko->ko_source, base, size, off,
 110             UIO_SYSSPACE, IO_NODELOCKED, curlwp->l_cred, &resid,
 111             curlwp);
 112
 113         if (error == 0 && resid != 0) {
 114                 error = EINVAL;
 115         }
 116
 117         if (allocate && error != 0) {
 118                 kmem_free(base, size);
 119                 base = NULL;
 120         }
 121
 122         if (allocate)
 123                 *basep = base;
 124
 125         return error;
 126 }
 127
 128 /*
 129  * kobj_load_file:
 130  *
 131  *      Load an object located in the file system.
 132  */
 133 int
 134 kobj_load_file(kobj_t *kop, const char *path, const bool nochroot)
 135 {
 136         struct nameidata nd;
 137         kauth_cred_t cred;
 138         int error;
 139         kobj_t ko;
 140
 141         cred = kauth_cred_get();
 142
 143         ko = kmem_zalloc(sizeof(*ko), KM_SLEEP);
 144         if (ko == NULL) {
 145                 return ENOMEM;
 146         }
 147
 148         NDINIT(&nd, LOOKUP, FOLLOW | (nochroot ? NOCHROOT : 0),
 149             UIO_SYSSPACE, path);
 150         error = vn_open(&nd, FREAD, 0);
 151
 152         if (error != 0) {
 153                 kmem_free(ko, sizeof(*ko));
 154                 return error;
 155         }
 156
 157         ko->ko_type = KT_VNODE;
 158         ko->ko_source = nd.ni_vp;
 159         ko->ko_read = kobj_read_file;
 160         ko->ko_close = kobj_close_file;
 161
 162         *kop = ko;
 163         return kobj_load(ko);
 164 }
 165
 166 #else /* MODULAR */
 167
 168 int
 169 kobj_load_file(kobj_t *kop, const char *path, const bool nochroot)
 170 {
 171
 172         return ENOSYS;
 173 }
 174
 175 #endif