bsd/vm/dp_backing_file.c

   1 /*
   2  * Copyright (c) 2000-2010 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /*
  29  * NOTICE: This file was modified by SPARTA, Inc. in 2005 to introduce
  30  * support for mandatory and extensible security protections.  This notice
  31  * is included in support of clause 2.2 (b) of the Apple Public License,
  32  * Version 2.0.
  33  */
  34
  35 #include <sys/param.h>
  36 #include <sys/systm.h>
  37 #include <sys/lock.h>
  38 #include <sys/proc_internal.h>
  39 #include <sys/kauth.h>
  40 #include <sys/buf.h>
  41 #include <sys/uio.h>
  42 #include <sys/vnode_internal.h>
  43 #include <sys/namei.h>
  44 #include <sys/ubc_internal.h>
  45 #include <sys/malloc.h>
  46 #include <sys/user.h>
  47
  48 #include <default_pager/default_pager_types.h>
  49
  50 #include <security/audit/audit.h>
  51 #include <bsm/audit_kevents.h>
  52
  53 #include <mach/mach_types.h>
  54 #include <mach/host_priv.h>
  55 #include <mach/mach_traps.h>
  56 #include <mach/boolean.h>
  57
  58 #include <kern/kern_types.h>
  59 #include <kern/locks.h>
  60 #include <kern/host.h>
  61 #include <kern/task.h>
  62 #include <kern/zalloc.h>
  63 #include <kern/policy_internal.h>
  64
  65 #include <libkern/libkern.h>
  66
  67 #include <vm/vm_pageout.h>
  68 #include <vm/vm_map.h>
  69 #include <vm/vm_kern.h>
  70 #include <vm/vnode_pager.h>
  71 #include <vm/vm_protos.h>
  72 #if CONFIG_MACF
  73 #include <security/mac_framework.h>
  74 #endif
  75
  76 #include <pexpert/pexpert.h>
  77
  78
  79 /*
  80  *      Routine:        macx_backing_store_recovery
  81  *      Function:
  82  *              Syscall interface to set a tasks privilege
  83  *              level so that it is not subject to
  84  *              macx_backing_store_suspend
  85  */
  86 int
  87 macx_backing_store_recovery(
  88         __unused struct macx_backing_store_recovery_args *args)
  89 {
  90         return ENOTSUP;
  91 }
  92
  93 /*
  94  *      Routine:        macx_backing_store_suspend
  95  *      Function:
  96  *              Syscall interface to stop new demand for
  97  *              backing store when backing store is low
  98  */
  99
 100 int
 101 macx_backing_store_suspend(
 102         __unused struct macx_backing_store_suspend_args *args)
 103 {
 104         return ENOTSUP;
 105 }
 106
 107
 108 extern boolean_t compressor_store_stop_compaction;
 109
 110 /*
 111  *      Routine:        macx_backing_store_compaction
 112  *      Function:
 113  *              Turn compaction of swap space on or off.  This is
 114  *              used during shutdown/restart so that the kernel
 115  *              doesn't waste time compacting swap files that are
 116  *              about to be deleted anyway.  Compaction is always
 117  *              on by default when the system comes up and is turned
 118  *              off when a shutdown/restart is requested.  It is
 119  *              re-enabled if the shutdown/restart is aborted for any reason.
 120  *
 121  *  This routine assumes macx_lock has been locked by macx_triggers ->
 122  *      mach_macx_triggers -> macx_backing_store_compaction
 123  */
 124
 125 int
 126 macx_backing_store_compaction(int flags)
 127 {
 128         int error;
 129
 130         if ((error = suser(kauth_cred_get(), 0))) {
 131                 return error;
 132         }
 133
 134         if (flags & SWAP_COMPACT_DISABLE) {
 135                 compressor_store_stop_compaction = TRUE;
 136
 137                 kprintf("compressor_store_stop_compaction = TRUE\n");
 138         } else if (flags & SWAP_COMPACT_ENABLE) {
 139                 compressor_store_stop_compaction = FALSE;
 140
 141                 kprintf("compressor_store_stop_compaction = FALSE\n");
 142         }
 143
 144         return 0;
 145 }
 146
 147 /*
 148  *      Routine:        macx_triggers
 149  *      Function:
 150  *              Syscall interface to set the call backs for low and
 151  *              high water marks.
 152  */
 153 int
 154 macx_triggers(
 155         struct macx_triggers_args *args)
 156 {
 157         int     flags = args->flags;
 158
 159         if (flags & (SWAP_COMPACT_DISABLE | SWAP_COMPACT_ENABLE)) {
 160                 return macx_backing_store_compaction(flags);
 161         }
 162
 163         return ENOTSUP;
 164 }
 165
 166
 167 int
 168 macx_swapon(
 169         __unused struct macx_swapon_args *args)
 170 {
 171         return ENOTSUP;
 172 }
 173
 174
 175 /*
 176  *      Routine:        macx_swapoff
 177  *      Function:
 178  *              Syscall interface to remove a file from backing store
 179  */
 180 int
 181 macx_swapoff(
 182         __unused struct macx_swapoff_args *args)
 183 {
 184         return ENOTSUP;
 185 }
 186
 187 /*
 188  *      Routine:        macx_swapinfo
 189  *      Function:
 190  *              Syscall interface to get general swap statistics
 191  */
 192 extern uint64_t vm_swap_get_total_space(void);
 193 extern uint64_t vm_swap_get_free_space(void);
 194 extern boolean_t vm_swap_up;
 195
 196 int
 197 macx_swapinfo(
 198         memory_object_size_t    *total_p,
 199         memory_object_size_t    *avail_p,
 200         vm_size_t               *pagesize_p,
 201         boolean_t               *encrypted_p)
 202 {
 203         if (VM_CONFIG_SWAP_IS_PRESENT) {
 204                 *total_p = vm_swap_get_total_space();
 205                 *avail_p = vm_swap_get_free_space();
 206                 *pagesize_p = (vm_size_t)PAGE_SIZE_64;
 207                 *encrypted_p = TRUE;
 208         } else {
 209                 *total_p = 0;
 210                 *avail_p = 0;
 211                 *pagesize_p = 0;
 212                 *encrypted_p = FALSE;
 213         }
 214         return 0;
 215 }