arch/x86/kernel/platform/i86pc/include/vm/hment.h

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 #ifndef _VM_HMENT_H
  28 #define _VM_HMENT_H
  29
  30 #pragma ident   "%Z%%M% %I%     %E% SMI"
  31
  32 #ifdef  __cplusplus
  33 extern "C" {
  34 #endif
  35
  36
  37 struct hment;
  38 typedef struct hment hment_t;
  39
  40 #if defined(_KERNEL)
  41
  42 /*
  43  * Remove a page mapping, finds the matching mapping and unlinks it from
  44  * the page_t. If it returns a non-NULL pointer, the pointer must be
  45  * freed via hment_free() after doing x86_hm_exit().
  46  */
  47 extern hment_t *hment_remove(page_t *, htable_t *ht, uint_t entry);
  48 extern void hment_free(hment_t *);
  49
  50 /*
  51  * Iterator to walk through all mappings of a page.
  52  */
  53 extern hment_t *hment_walk(page_t *, htable_t **, uint_t *, hment_t *);
  54
  55 /*
  56  * Prepare a page for a new mapping
  57  */
  58 extern hment_t *hment_prepare(htable_t *ht, uint_t entry, page_t *);
  59
  60 /*
  61  * Add a mapping to a page's mapping list
  62  */
  63 extern void hment_assign(htable_t *ht, uint_t entry, page_t *, hment_t *);
  64
  65 /*
  66  * initialize hment data structures
  67  */
  68 extern void hment_init(void);
  69
  70 /*
  71  * lock/unlock a page_t's mapping list/pte entry
  72  */
  73 extern void x86_hm_enter(page_t *);
  74 extern void x86_hm_exit(page_t *);
  75 extern int x86_hm_held(page_t *pp);
  76
  77 /*
  78  * Called to allocate additional hments for reserve.
  79  *
  80  * The hment_reserve_count is exported for use by htable_hment_steal()
  81  */
  82 extern void hment_reserve(uint_t);
  83 extern uint_t hment_reserve_count;
  84
  85 /*
  86  * Used to readjust the hment reserve after the reserve list has been used.
  87  * Also called after boot to release left over boot reserves.
  88  */
  89 extern void hment_adjust_reserve(void);
  90
  91 /*
  92  * Return the number of mappings of a page_t
  93  */
  94 extern uint_t hment_mapcnt(page_t *);
  95
  96 #endif  /* _KERNEL */
  97
  98
  99 #ifdef  __cplusplus
 100 }
 101 #endif
 102
 103 #endif  /* _VM_HMENT_H */