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 /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */ 28 /* All Rights Reserved */ 29 30 /* 31 * University Copyright- Copyright (c) 1982, 1986, 1988 32 * The Regents of the University of California 33 * All Rights Reserved 34 * 35 * University Acknowledgment- Portions of this document are derived from 36 * software developed by the University of California, Berkeley, and its 37 * contributors. 38 */ 39 40 #ifndef _VM_SEG_VN_H 41 #define _VM_SEG_VN_H 42 43 #pragma ident "%Z%%M% %I% %E% SMI" 44 45 #include <sys/lgrp.h> 46 #include <vm/anon.h> 47 48 #ifdef __cplusplus 49 extern "C" { 50 #endif 51 52 /* 53 * A pointer to this structure is passed to segvn_create(). 54 */ 55 typedef struct segvn_crargs { 56 struct vnode *vp; /* vnode mapped from */ 57 struct cred *cred; /* credentials */ 58 u_offset_t offset; /* starting offset of vnode for mapping */ 59 uchar_t type; /* type of sharing done */ 60 uchar_t prot; /* protections */ 61 uchar_t maxprot; /* maximum protections */ 62 uint_t flags; /* flags */ 63 struct anon_map *amp; /* anon mapping to map to */ 64 uint_t szc; /* max preferred page size code */ 65 uint_t lgrp_mem_policy_flags; 66 } segvn_crargs_t; 67 68 /* 69 * (Semi) private data maintained by the seg_vn driver per segment mapping. 70 * 71 * The read/write segment lock protects all of segvn_data including the 72 * vpage array. All fields in segvn_data are treated as read-only when 73 * the "read" version of the address space and the segment locks are held. 74 * The "write" version of the segment lock, however, is required in order to 75 * update the following fields: 76 * 77 * pageprot 78 * prot 79 * amp 80 * vpage 81 * 82 * softlockcnt 83 * is written by acquiring either the readers lock on the segment and 84 * freemem lock, or any lock combination which guarantees exclusive use 85 * of this segment (e.g., adress space writers lock, 86 * address space readers lock + segment writers lock). 87 */ 88 typedef struct segvn_data { 89 krwlock_t lock; /* protect segvn_data and vpage array */ 90 kmutex_t segp_slock; /* serialize insertions into seg_pcache */ 91 uchar_t pageprot; /* true if per page protections present */ 92 uchar_t prot; /* current segment prot if pageprot == 0 */ 93 uchar_t maxprot; /* maximum segment protections */ 94 uchar_t type; /* type of sharing done */ 95 u_offset_t offset; /* starting offset of vnode for mapping */ 96 struct vnode *vp; /* vnode that segment mapping is to */ 97 ulong_t anon_index; /* starting index into anon_map anon array */ 98 struct anon_map *amp; /* pointer to anon share structure, if needed */ 99 struct vpage *vpage; /* per-page information, if needed */ 100 struct cred *cred; /* mapping credentials */ 101 size_t swresv; /* swap space reserved for this segment */ 102 uchar_t advice; /* madvise flags for segment */ 103 uchar_t pageadvice; /* true if per page advice set */ 104 ushort_t flags; /* flags - from sys/mman.h */ 105 ssize_t softlockcnt; /* # of pages SOFTLOCKED in seg */ 106 lgrp_mem_policy_info_t policy_info; /* memory allocation policy */ 107 } segvn_data_t; 108 109 #ifdef _KERNEL 110 111 /* 112 * Macros for segvn segment driver locking. 113 */ 114 #define SEGVN_LOCK_ENTER(as, lock, type) rw_enter((lock), (type)) 115 #define SEGVN_LOCK_EXIT(as, lock) rw_exit((lock)) 116 #define SEGVN_LOCK_DOWNGRADE(as, lock) rw_downgrade((lock)) 117 118 /* 119 * Macros to test lock states. 120 */ 121 #define SEGVN_LOCK_HELD(as, lock) RW_LOCK_HELD((lock)) 122 #define SEGVN_READ_HELD(as, lock) RW_READ_HELD((lock)) 123 #define SEGVN_WRITE_HELD(as, lock) RW_WRITE_HELD((lock)) 124 125 /* 126 * Macro used to detect the need to Break the sharing of COW pages 127 * 128 * The rw == S_WRITE is for the COW case 129 * rw == S_READ and type == SOFTLOCK is for the physio case 130 * We don't want to share a softlocked page because it can cause problems 131 * with multithreaded apps but if rw == S_READ_NOCOW it's ok to not break 132 * sharing of COW pages even in SOFTLOCK case. 133 */ 134 #define BREAK_COW_SHARE(rw, type, seg_type) ((rw == S_WRITE || \ 135 (type == F_SOFTLOCK && rw != S_READ_NOCOW)) && \ 136 seg_type == MAP_PRIVATE) 137 138 #define SEGVN_ZFOD_ARGS(prot, max) \ 139 { NULL, NULL, 0, MAP_PRIVATE, prot, max, 0, NULL, 0, 0 } 140 141 #define AS_MAP_VNSEGS_USELPGS(crfp, argsp) \ 142 ((crfp) == (int (*)())segvn_create && \ 143 (((struct segvn_crargs *)(argsp))->flags & \ 144 (MAP_TEXT | MAP_INITDATA)) && \ 145 ((struct segvn_crargs *)(argsp))->vp != NULL && \ 146 ((struct segvn_crargs *)(argsp))->amp == NULL) 147 148 149 extern void segvn_init(void); 150 extern int segvn_create(struct seg *, void *); 151 152 extern struct seg_ops segvn_ops; 153 154 /* 155 * Provided as shorthand for creating user zfod segments. 156 */ 157 extern caddr_t zfod_argsp; 158 extern caddr_t kzfod_argsp; 159 extern caddr_t stack_exec_argsp; 160 extern caddr_t stack_noexec_argsp; 161 162 #endif /* _KERNEL */ 163 164 #ifdef __cplusplus 165 } 166 #endif 167 168 #endif /* _VM_SEG_VN_H */ 169