tmpfs_mem.c revision 1.2.2.2
1 1.2.2.2 rmind /* $NetBSD: tmpfs_mem.c,v 1.2.2.2 2010/07/03 01:19:51 rmind Exp $ */ 2 1.2.2.2 rmind 3 1.2.2.2 rmind /* 4 1.2.2.2 rmind * Copyright (c) 2010 The NetBSD Foundation, Inc. 5 1.2.2.2 rmind * All rights reserved. 6 1.2.2.2 rmind * 7 1.2.2.2 rmind * Redistribution and use in source and binary forms, with or without 8 1.2.2.2 rmind * modification, are permitted provided that the following conditions 9 1.2.2.2 rmind * are met: 10 1.2.2.2 rmind * 1. Redistributions of source code must retain the above copyright 11 1.2.2.2 rmind * notice, this list of conditions and the following disclaimer. 12 1.2.2.2 rmind * 2. Redistributions in binary form must reproduce the above copyright 13 1.2.2.2 rmind * notice, this list of conditions and the following disclaimer in the 14 1.2.2.2 rmind * documentation and/or other materials provided with the distribution. 15 1.2.2.2 rmind * 16 1.2.2.2 rmind * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 17 1.2.2.2 rmind * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 18 1.2.2.2 rmind * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 19 1.2.2.2 rmind * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 20 1.2.2.2 rmind * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 21 1.2.2.2 rmind * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 22 1.2.2.2 rmind * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 23 1.2.2.2 rmind * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 24 1.2.2.2 rmind * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 25 1.2.2.2 rmind * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 26 1.2.2.2 rmind * POSSIBILITY OF SUCH DAMAGE. 27 1.2.2.2 rmind */ 28 1.2.2.2 rmind 29 1.2.2.2 rmind /* 30 1.2.2.2 rmind * tmpfs memory allocation routines. 31 1.2.2.2 rmind * Implements memory usage accounting and limiting. 32 1.2.2.2 rmind */ 33 1.2.2.2 rmind 34 1.2.2.2 rmind #include <sys/cdefs.h> 35 1.2.2.2 rmind __KERNEL_RCSID(0, "$NetBSD: tmpfs_mem.c,v 1.2.2.2 2010/07/03 01:19:51 rmind Exp $"); 36 1.2.2.2 rmind 37 1.2.2.2 rmind #include <sys/param.h> 38 1.2.2.2 rmind #include <sys/atomic.h> 39 1.2.2.2 rmind #include <sys/kmem.h> 40 1.2.2.2 rmind #include <sys/namei.h> 41 1.2.2.2 rmind #include <sys/pool.h> 42 1.2.2.2 rmind 43 1.2.2.2 rmind #include <fs/tmpfs/tmpfs.h> 44 1.2.2.2 rmind 45 1.2.2.2 rmind void 46 1.2.2.2 rmind tmpfs_mntmem_init(struct tmpfs_mount *mp, uint64_t memlimit) 47 1.2.2.2 rmind { 48 1.2.2.2 rmind 49 1.2.2.2 rmind sprintf(mp->tm_dwchan, "tmpfs_dirent_%p", mp); 50 1.2.2.2 rmind pool_init(&mp->tm_dirent_pool, sizeof(struct tmpfs_dirent), 0, 0, 0, 51 1.2.2.2 rmind mp->tm_dwchan, &pool_allocator_nointr, IPL_NONE); 52 1.2.2.2 rmind 53 1.2.2.2 rmind sprintf(mp->tm_nwchan, "tmpfs_node_%p", mp); 54 1.2.2.2 rmind pool_init(&mp->tm_node_pool, sizeof(struct tmpfs_node), 0, 0, 0, 55 1.2.2.2 rmind mp->tm_dwchan, &pool_allocator_nointr, IPL_NONE); 56 1.2.2.2 rmind 57 1.2.2.2 rmind mutex_init(&mp->tm_acc_lock, MUTEX_DEFAULT, IPL_NONE); 58 1.2.2.2 rmind mp->tm_mem_limit = memlimit; 59 1.2.2.2 rmind mp->tm_bytes_used = 0; 60 1.2.2.2 rmind } 61 1.2.2.2 rmind 62 1.2.2.2 rmind void 63 1.2.2.2 rmind tmpfs_mntmem_destroy(struct tmpfs_mount *mp) 64 1.2.2.2 rmind { 65 1.2.2.2 rmind 66 1.2.2.2 rmind KASSERT(mp->tm_bytes_used == 0); 67 1.2.2.2 rmind mutex_destroy(&mp->tm_acc_lock); 68 1.2.2.2 rmind pool_destroy(&mp->tm_dirent_pool); 69 1.2.2.2 rmind pool_destroy(&mp->tm_node_pool); 70 1.2.2.2 rmind } 71 1.2.2.2 rmind 72 1.2.2.2 rmind /* 73 1.2.2.2 rmind * tmpfs_mem_info: return the number of available memory pages. 74 1.2.2.2 rmind * 75 1.2.2.2 rmind * => If 'total' is true, then return _total_ amount of pages. 76 1.2.2.2 rmind * => If false, then return the amount of _free_ memory pages. 77 1.2.2.2 rmind * 78 1.2.2.2 rmind * Remember to remove TMPFS_PAGES_RESERVED from the returned value to avoid 79 1.2.2.2 rmind * excessive memory usage. 80 1.2.2.2 rmind */ 81 1.2.2.2 rmind size_t 82 1.2.2.2 rmind tmpfs_mem_info(bool total) 83 1.2.2.2 rmind { 84 1.2.2.2 rmind size_t size = 0; 85 1.2.2.2 rmind 86 1.2.2.2 rmind /* XXX: unlocked */ 87 1.2.2.2 rmind size += uvmexp.swpgavail; 88 1.2.2.2 rmind if (!total) { 89 1.2.2.2 rmind size -= uvmexp.swpgonly; 90 1.2.2.2 rmind } 91 1.2.2.2 rmind size += uvmexp.free; 92 1.2.2.2 rmind size += uvmexp.filepages; 93 1.2.2.2 rmind if (size > uvmexp.wired) { 94 1.2.2.2 rmind size -= uvmexp.wired; 95 1.2.2.2 rmind } else { 96 1.2.2.2 rmind size = 0; 97 1.2.2.2 rmind } 98 1.2.2.2 rmind return size; 99 1.2.2.2 rmind } 100 1.2.2.2 rmind 101 1.2.2.2 rmind uint64_t 102 1.2.2.2 rmind tmpfs_bytes_max(struct tmpfs_mount *mp) 103 1.2.2.2 rmind { 104 1.2.2.2 rmind size_t freepages = tmpfs_mem_info(false); 105 1.2.2.2 rmind uint64_t avail_mem; 106 1.2.2.2 rmind 107 1.2.2.2 rmind if (freepages < TMPFS_PAGES_RESERVED) { 108 1.2.2.2 rmind freepages = 0; 109 1.2.2.2 rmind } else { 110 1.2.2.2 rmind freepages -= TMPFS_PAGES_RESERVED; 111 1.2.2.2 rmind } 112 1.2.2.2 rmind avail_mem = round_page(mp->tm_bytes_used) + (freepages << PAGE_SHIFT); 113 1.2.2.2 rmind return MIN(mp->tm_mem_limit, avail_mem); 114 1.2.2.2 rmind } 115 1.2.2.2 rmind 116 1.2.2.2 rmind size_t 117 1.2.2.2 rmind tmpfs_pages_avail(struct tmpfs_mount *mp) 118 1.2.2.2 rmind { 119 1.2.2.2 rmind 120 1.2.2.2 rmind return (tmpfs_bytes_max(mp) - mp->tm_bytes_used) >> PAGE_SHIFT; 121 1.2.2.2 rmind } 122 1.2.2.2 rmind 123 1.2.2.2 rmind bool 124 1.2.2.2 rmind tmpfs_mem_incr(struct tmpfs_mount *mp, size_t sz) 125 1.2.2.2 rmind { 126 1.2.2.2 rmind uint64_t lim; 127 1.2.2.2 rmind 128 1.2.2.2 rmind mutex_enter(&mp->tm_acc_lock); 129 1.2.2.2 rmind lim = tmpfs_bytes_max(mp); 130 1.2.2.2 rmind if (mp->tm_bytes_used + sz >= lim) { 131 1.2.2.2 rmind mutex_exit(&mp->tm_acc_lock); 132 1.2.2.2 rmind return false; 133 1.2.2.2 rmind } 134 1.2.2.2 rmind mp->tm_bytes_used += sz; 135 1.2.2.2 rmind mutex_exit(&mp->tm_acc_lock); 136 1.2.2.2 rmind return true; 137 1.2.2.2 rmind } 138 1.2.2.2 rmind 139 1.2.2.2 rmind void 140 1.2.2.2 rmind tmpfs_mem_decr(struct tmpfs_mount *mp, size_t sz) 141 1.2.2.2 rmind { 142 1.2.2.2 rmind 143 1.2.2.2 rmind mutex_enter(&mp->tm_acc_lock); 144 1.2.2.2 rmind KASSERT(mp->tm_bytes_used >= sz); 145 1.2.2.2 rmind mp->tm_bytes_used -= sz; 146 1.2.2.2 rmind mutex_exit(&mp->tm_acc_lock); 147 1.2.2.2 rmind } 148 1.2.2.2 rmind 149 1.2.2.2 rmind struct tmpfs_dirent * 150 1.2.2.2 rmind tmpfs_dirent_get(struct tmpfs_mount *mp) 151 1.2.2.2 rmind { 152 1.2.2.2 rmind 153 1.2.2.2 rmind if (!tmpfs_mem_incr(mp, sizeof(struct tmpfs_dirent))) { 154 1.2.2.2 rmind return NULL; 155 1.2.2.2 rmind } 156 1.2.2.2 rmind return pool_get(&mp->tm_dirent_pool, PR_WAITOK); 157 1.2.2.2 rmind } 158 1.2.2.2 rmind 159 1.2.2.2 rmind void 160 1.2.2.2 rmind tmpfs_dirent_put(struct tmpfs_mount *mp, struct tmpfs_dirent *de) 161 1.2.2.2 rmind { 162 1.2.2.2 rmind 163 1.2.2.2 rmind tmpfs_mem_decr(mp, sizeof(struct tmpfs_dirent)); 164 1.2.2.2 rmind pool_put(&mp->tm_dirent_pool, de); 165 1.2.2.2 rmind } 166 1.2.2.2 rmind 167 1.2.2.2 rmind struct tmpfs_node * 168 1.2.2.2 rmind tmpfs_node_get(struct tmpfs_mount *mp) 169 1.2.2.2 rmind { 170 1.2.2.2 rmind 171 1.2.2.2 rmind if (!tmpfs_mem_incr(mp, sizeof(struct tmpfs_node))) { 172 1.2.2.2 rmind return NULL; 173 1.2.2.2 rmind } 174 1.2.2.2 rmind return pool_get(&mp->tm_node_pool, PR_WAITOK); 175 1.2.2.2 rmind } 176 1.2.2.2 rmind 177 1.2.2.2 rmind void 178 1.2.2.2 rmind tmpfs_node_put(struct tmpfs_mount *mp, struct tmpfs_node *tn) 179 1.2.2.2 rmind { 180 1.2.2.2 rmind 181 1.2.2.2 rmind tmpfs_mem_decr(mp, sizeof(struct tmpfs_node)); 182 1.2.2.2 rmind pool_put(&mp->tm_node_pool, tn); 183 1.2.2.2 rmind } 184 1.2.2.2 rmind 185 1.2.2.2 rmind /* 186 1.2.2.2 rmind * Quantum size to round-up the tmpfs names in order to reduce re-allocations. 187 1.2.2.2 rmind */ 188 1.2.2.2 rmind 189 1.2.2.2 rmind #define TMPFS_NAME_QUANTUM (32) 190 1.2.2.2 rmind 191 1.2.2.2 rmind char * 192 1.2.2.2 rmind tmpfs_strname_alloc(struct tmpfs_mount *mp, size_t len) 193 1.2.2.2 rmind { 194 1.2.2.2 rmind const size_t sz = roundup2(len, TMPFS_NAME_QUANTUM); 195 1.2.2.2 rmind 196 1.2.2.2 rmind KASSERT(sz > 0 && sz <= 1024); 197 1.2.2.2 rmind if (!tmpfs_mem_incr(mp, sz)) { 198 1.2.2.2 rmind return NULL; 199 1.2.2.2 rmind } 200 1.2.2.2 rmind return kmem_alloc(sz, KM_SLEEP); 201 1.2.2.2 rmind } 202 1.2.2.2 rmind 203 1.2.2.2 rmind void 204 1.2.2.2 rmind tmpfs_strname_free(struct tmpfs_mount *mp, char *str, size_t len) 205 1.2.2.2 rmind { 206 1.2.2.2 rmind const size_t sz = roundup2(len, TMPFS_NAME_QUANTUM); 207 1.2.2.2 rmind 208 1.2.2.2 rmind KASSERT(sz > 0 && sz <= 1024); 209 1.2.2.2 rmind tmpfs_mem_decr(mp, sz); 210 1.2.2.2 rmind kmem_free(str, sz); 211 1.2.2.2 rmind } 212 1.2.2.2 rmind 213 1.2.2.2 rmind bool 214 1.2.2.2 rmind tmpfs_strname_neqlen(struct componentname *fcnp, struct componentname *tcnp) 215 1.2.2.2 rmind { 216 1.2.2.2 rmind const size_t fln = roundup2(fcnp->cn_namelen, TMPFS_NAME_QUANTUM); 217 1.2.2.2 rmind const size_t tln = roundup2(tcnp->cn_namelen, TMPFS_NAME_QUANTUM); 218 1.2.2.2 rmind 219 1.2.2.2 rmind return (fln != tln) || memcmp(fcnp->cn_nameptr, tcnp->cn_nameptr, fln); 220 1.2.2.2 rmind } 221
Indexes created Mon Sep 29 21:09:56 GMT 2025