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 (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright 2006 Sun Microsystems, Inc. All rights reserved. 23 * Use is subject to license terms. 24 */ 25 26 /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */ 27 /* All Rights Reserved */ 28 29 /* 30 * University Copyright- Copyright (c) 1982, 1986, 1988 31 * The Regents of the University of California 32 * All Rights Reserved 33 * 34 * University Acknowledgment- Portions of this document are derived from 35 * software developed by the University of California, Berkeley, and its 36 * contributors. 37 */ 38 39 #ifndef _VM_SEG_VN_H 40 #define _VM_SEG_VN_H 41 42 #pragma ident "%Z%%M% %I% %E% SMI" 43 44 #include <sys/lgrp.h> 45 #include <vm/anon.h> 46 47 #ifdef __cplusplus 48 extern "C" { 49 #endif 50 51 /* 52 * A pointer to this structure is passed to segvn_create(). 53 */ 54 typedef struct segvn_crargs { 55 struct vnode *vp; /* vnode mapped from */ 56 struct cred *cred; /* credentials */ 57 u_offset_t offset; /* starting offset of vnode for mapping */ 58 uchar_t type; /* type of sharing done */ 59 uchar_t prot; /* protections */ 60 uchar_t maxprot; /* maximum protections */ 61 uint_t flags; /* flags */ 62 struct anon_map *amp; /* anon mapping to map to */ 63 uint_t szc; /* max preferred page size code */ 64 uint_t lgrp_mem_policy_flags; 65 } segvn_crargs_t; 66 67 /* 68 * (Semi) private data maintained by the seg_vn driver per segment mapping. 69 * 70 * The read/write segment lock protects all of segvn_data including the 71 * vpage array. All fields in segvn_data are treated as read-only when 72 * the "read" version of the address space and the segment locks are held. 73 * The "write" version of the segment lock, however, is required in order to 74 * update the following fields: 75 * 76 * pageprot 77 * prot 78 * amp 79 * vpage 80 * 81 * softlockcnt 82 * is written by acquiring either the readers lock on the segment and 83 * freemem lock, or any lock combination which guarantees exclusive use 84 * of this segment (e.g., adress space writers lock, 85 * address space readers lock + segment writers lock). 86 */ 87 typedef struct segvn_data { 88 krwlock_t lock; /* protect segvn_data and vpage array */ 89 kmutex_t segp_slock; /* serialize insertions into seg_pcache */ 90 uchar_t pageprot; /* true if per page protections present */ 91 uchar_t prot; /* current segment prot if pageprot == 0 */ 92 uchar_t maxprot; /* maximum segment protections */ 93 uchar_t type; /* type of sharing done */ 94 u_offset_t offset; /* starting offset of vnode for mapping */ 95 struct vnode *vp; /* vnode that segment mapping is to */ 96 ulong_t anon_index; /* starting index into anon_map anon array */ 97 struct anon_map *amp; /* pointer to anon share structure, if needed */ 98 struct vpage *vpage; /* per-page information, if needed */ 99 struct cred *cred; /* mapping credentials */ 100 size_t swresv; /* swap space reserved for this segment */ 101 uchar_t advice; /* madvise flags for segment */ 102 uchar_t pageadvice; /* true if per page advice set */ 103 ushort_t flags; /* flags - from sys/mman.h */ 104 ssize_t softlockcnt; /* # of pages SOFTLOCKED in seg */ 105 lgrp_mem_policy_info_t policy_info; /* memory allocation policy */ 106 } segvn_data_t; 107 108 #ifdef _KERNEL 109 110 /* 111 * Macros for segvn segment driver locking. 112 */ 113 #define SEGVN_LOCK_ENTER(as, lock, type) rw_enter((lock), (type)) 114 #define SEGVN_LOCK_EXIT(as, lock) rw_exit((lock)) 115 #define SEGVN_LOCK_DOWNGRADE(as, lock) rw_downgrade((lock)) 116 117 /* 118 * Macros to test lock states. 119 */ 120 #define SEGVN_LOCK_HELD(as, lock) RW_LOCK_HELD((lock)) 121 #define SEGVN_READ_HELD(as, lock) RW_READ_HELD((lock)) 122 #define SEGVN_WRITE_HELD(as, lock) RW_WRITE_HELD((lock)) 123 124 /* 125 * Macro used to detect the need to Break the sharing of COW pages 126 * 127 * The rw == S_WRITE is for the COW case 128 * rw == S_READ and type == SOFTLOCK is for the physio case 129 * We don't want to share a softlocked page because it can cause problems 130 * with multithreaded apps but if rw == S_READ_NOCOW it's ok to not break 131 * sharing of COW pages even in SOFTLOCK case. 132 */ 133 #define BREAK_COW_SHARE(rw, type, seg_type) ((rw == S_WRITE || \ 134 (type == F_SOFTLOCK && rw != S_READ_NOCOW)) && \ 135 seg_type == MAP_PRIVATE) 136 137 #define SEGVN_ZFOD_ARGS(prot, max) \ 138 { NULL, NULL, 0, MAP_PRIVATE, prot, max, 0, NULL, 0, 0 } 139 140 #define AS_MAP_VNSEGS_USELPGS(crfp, argsp) \ 141 ((crfp) == (int (*)())segvn_create && \ 142 (((struct segvn_crargs *)(argsp))->flags & \ 143 (MAP_TEXT | MAP_INITDATA)) && \ 144 ((struct segvn_crargs *)(argsp))->vp != NULL && \ 145 ((struct segvn_crargs *)(argsp))->amp == NULL) 146 147 #define AS_MAP_SHAMP(crfp, argsp) \ 148 ((crfp) == (int (*)())segvn_create && \ 149 ((struct segvn_crargs *)(argsp))->type == MAP_SHARED && \ 150 ((struct segvn_crargs *)(argsp))->vp == NULL) 151 152 extern void segvn_init(void); 153 extern int segvn_create(struct seg *, void *); 154 155 extern struct seg_ops segvn_ops; 156 157 /* 158 * Provided as shorthand for creating user zfod segments. 159 */ 160 extern caddr_t zfod_argsp; 161 extern caddr_t kzfod_argsp; 162 extern caddr_t stack_exec_argsp; 163 extern caddr_t stack_noexec_argsp; 164 165 #endif /* _KERNEL */ 166 167 #ifdef __cplusplus 168 } 169 #endif 170 171 #endif /* _VM_SEG_VN_H */ 172