1ae115bc7Smrj /* 2ae115bc7Smrj * CDDL HEADER START 3ae115bc7Smrj * 4ae115bc7Smrj * The contents of this file are subject to the terms of the 5ae115bc7Smrj * Common Development and Distribution License (the "License"). 6ae115bc7Smrj * You may not use this file except in compliance with the License. 7ae115bc7Smrj * 8ae115bc7Smrj * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9ae115bc7Smrj * or http://www.opensolaris.org/os/licensing. 10ae115bc7Smrj * See the License for the specific language governing permissions 11ae115bc7Smrj * and limitations under the License. 12ae115bc7Smrj * 13ae115bc7Smrj * When distributing Covered Code, include this CDDL HEADER in each 14ae115bc7Smrj * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15ae115bc7Smrj * If applicable, add the following below this CDDL HEADER, with the 16ae115bc7Smrj * fields enclosed by brackets "[]" replaced with your own identifying 17ae115bc7Smrj * information: Portions Copyright [yyyy] [name of copyright owner] 18ae115bc7Smrj * 19ae115bc7Smrj * CDDL HEADER END 20ae115bc7Smrj */ 21ae115bc7Smrj /* 22ae115bc7Smrj * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 23ae115bc7Smrj * Use is subject to license terms. 24ae115bc7Smrj */ 25ae115bc7Smrj 26ae115bc7Smrj #ifndef _SYS_HOLD_PAGE_H 27ae115bc7Smrj #define _SYS_HOLD_PAGE_H 28ae115bc7Smrj 29ae115bc7Smrj #pragma ident "%Z%%M% %I% %E% SMI" 30ae115bc7Smrj 31ae115bc7Smrj #ifdef __cplusplus 32ae115bc7Smrj extern "C" { 33ae115bc7Smrj #endif 34ae115bc7Smrj 35ae115bc7Smrj #include <sys/types.h> 36ae115bc7Smrj #include <vm/page.h> 37ae115bc7Smrj 38ae115bc7Smrj /* 39ae115bc7Smrj * swrand generates entropy by mapping different pages in the system. This 40ae115bc7Smrj * can create problems for some hypervisors, as certain pages may be removed 41ae115bc7Smrj * from the system at any time. The following interfaces allow swrand to 42ae115bc7Smrj * check the validity and make sure a page is not given away while it is mapped. 43ae115bc7Smrj * 44ae115bc7Smrj * int plat_hold_page(pfn_t pfn, int lock, page_t **pp_ret) 45ae115bc7Smrj * 46ae115bc7Smrj * If lock is PLAT_HOLD_NO_LOCK, simply check if the page pfn is valid 47ae115bc7Smrj * in the system. If the page is valid, PLAT_HOLD_OK will be returned. 48ae115bc7Smrj * pp_ret is ignored if lock is PLAT_HOLD_NO_LOCK. 49ae115bc7Smrj * 50ae115bc7Smrj * If lock is PLAT_HOLD_LOCK, in addition to the above, attempt to lock 51ae115bc7Smrj * the page exclusively. Again, if the lock is successful, the page 52*843e1988Sjohnlev * pointer will be put in pp_ret, and PLAT_HOLD_OK will be returned. 53*843e1988Sjohnlev * pp_ret must be passed to a later call to plat_release_page. If the 54*843e1988Sjohnlev * page wasn't found, or the lock couldn't be grabbed, the return value 55*843e1988Sjohnlev * will be PLAT_HOLD_FAIL. 56ae115bc7Smrj * 57ae115bc7Smrj * void plat_release_page(page_t *pp) 58ae115bc7Smrj * 59ae115bc7Smrj * Unlock the page pp. Should only be called after a previous, 60*843e1988Sjohnlev * successful call to plat_hold_page(pfn, PLAT_HOLD_LOCK, &pp); 61ae115bc7Smrj */ 62ae115bc7Smrj 63ae115bc7Smrj #define PLAT_HOLD_NO_LOCK 0 64ae115bc7Smrj #define PLAT_HOLD_LOCK 1 65ae115bc7Smrj 66ae115bc7Smrj #define PLAT_HOLD_OK 0 67ae115bc7Smrj #define PLAT_HOLD_FAIL 1 68ae115bc7Smrj 69ae115bc7Smrj extern int plat_hold_page(pfn_t, int, page_t **); 70ae115bc7Smrj extern void plat_release_page(page_t *); 71ae115bc7Smrj 72ae115bc7Smrj #ifdef __cplusplus 73ae115bc7Smrj } 74ae115bc7Smrj #endif 75ae115bc7Smrj 76ae115bc7Smrj #endif /* _SYS_HOLD_PAGE_H */ 77