1/* 2 * fs/cifs/cache.c - CIFS filesystem cache index structure definitions 3 * 4 * Copyright (c) 2010 Novell, Inc. 5 * Authors(s): Suresh Jayaraman (sjayaraman@suse.de> 6 * 7 * This library is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU Lesser General Public License as published 9 * by the Free Software Foundation; either version 2.1 of the License, or 10 * (at your option) any later version. 11 * 12 * This library is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See 15 * the GNU Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public License 18 * along with this library; if not, write to the Free Software 19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 20 */ 21#include "fscache.h" 22#include "cifs_debug.h" 23 24/* 25 * CIFS filesystem definition for FS-Cache 26 */ 27struct fscache_netfs cifs_fscache_netfs = { 28 .name = "cifs", 29 .version = 0, 30}; 31 32/* 33 * Register CIFS for caching with FS-Cache 34 */ 35int cifs_fscache_register(void) 36{ 37 return fscache_register_netfs(&cifs_fscache_netfs); 38} 39 40/* 41 * Unregister CIFS for caching 42 */ 43void cifs_fscache_unregister(void) 44{ 45 fscache_unregister_netfs(&cifs_fscache_netfs); 46} 47 48/* 49 * Key layout of CIFS server cache index object 50 */ 51struct cifs_server_key { 52 uint16_t family; /* address family */ 53 uint16_t port; /* IP port */ 54 union { 55 struct in_addr ipv4_addr; 56 struct in6_addr ipv6_addr; 57 } addr[0]; 58}; 59 60/* 61 * Server object keyed by {IPaddress,port,family} tuple 62 */ 63static uint16_t cifs_server_get_key(const void *cookie_netfs_data, 64 void *buffer, uint16_t maxbuf) 65{ 66 const struct TCP_Server_Info *server = cookie_netfs_data; 67 const struct sockaddr *sa = (struct sockaddr *) &server->addr.sockAddr; 68 struct cifs_server_key *key = buffer; 69 uint16_t key_len = sizeof(struct cifs_server_key); 70 71 memset(key, 0, key_len); 72 73 /* 74 * Should not be a problem as sin_family/sin6_family overlays 75 * sa_family field 76 */ 77 switch (sa->sa_family) { 78 case AF_INET: 79 key->family = server->addr.sockAddr.sin_family; 80 key->port = server->addr.sockAddr.sin_port; 81 key->addr[0].ipv4_addr = server->addr.sockAddr.sin_addr; 82 key_len += sizeof(key->addr[0].ipv4_addr); 83 break; 84 85 case AF_INET6: 86 key->family = server->addr.sockAddr6.sin6_family; 87 key->port = server->addr.sockAddr6.sin6_port; 88 key->addr[0].ipv6_addr = server->addr.sockAddr6.sin6_addr; 89 key_len += sizeof(key->addr[0].ipv6_addr); 90 break; 91 92 default: 93 cERROR(1, "CIFS: Unknown network family '%d'", sa->sa_family); 94 key_len = 0; 95 break; 96 } 97 98 return key_len; 99} 100 101/* 102 * Server object for FS-Cache 103 */ 104const struct fscache_cookie_def cifs_fscache_server_index_def = { 105 .name = "CIFS.server", 106 .type = FSCACHE_COOKIE_TYPE_INDEX, 107 .get_key = cifs_server_get_key, 108}; 109 110/* 111 * Auxiliary data attached to CIFS superblock within the cache 112 */ 113struct cifs_fscache_super_auxdata { 114 u64 resource_id; /* unique server resource id */ 115}; 116 117static char *extract_sharename(const char *treename) 118{ 119 const char *src; 120 char *delim, *dst; 121 int len; 122 123 /* skip double chars at the beginning */ 124 src = treename + 2; 125 126 /* share name is always preceded by '\\' now */ 127 delim = strchr(src, '\\'); 128 if (!delim) 129 return ERR_PTR(-EINVAL); 130 delim++; 131 len = strlen(delim); 132 133 /* caller has to free the memory */ 134 dst = kstrndup(delim, len, GFP_KERNEL); 135 if (!dst) 136 return ERR_PTR(-ENOMEM); 137 138 return dst; 139} 140 141/* 142 * Superblock object currently keyed by share name 143 */ 144static uint16_t cifs_super_get_key(const void *cookie_netfs_data, void *buffer, 145 uint16_t maxbuf) 146{ 147 const struct cifsTconInfo *tcon = cookie_netfs_data; 148 char *sharename; 149 uint16_t len; 150 151 sharename = extract_sharename(tcon->treeName); 152 if (IS_ERR(sharename)) { 153 cFYI(1, "CIFS: couldn't extract sharename\n"); 154 sharename = NULL; 155 return 0; 156 } 157 158 len = strlen(sharename); 159 if (len > maxbuf) 160 return 0; 161 162 memcpy(buffer, sharename, len); 163 164 kfree(sharename); 165 166 return len; 167} 168 169static uint16_t 170cifs_fscache_super_get_aux(const void *cookie_netfs_data, void *buffer, 171 uint16_t maxbuf) 172{ 173 struct cifs_fscache_super_auxdata auxdata; 174 const struct cifsTconInfo *tcon = cookie_netfs_data; 175 176 memset(&auxdata, 0, sizeof(auxdata)); 177 auxdata.resource_id = tcon->resource_id; 178 179 if (maxbuf > sizeof(auxdata)) 180 maxbuf = sizeof(auxdata); 181 182 memcpy(buffer, &auxdata, maxbuf); 183 184 return maxbuf; 185} 186 187static enum 188fscache_checkaux cifs_fscache_super_check_aux(void *cookie_netfs_data, 189 const void *data, 190 uint16_t datalen) 191{ 192 struct cifs_fscache_super_auxdata auxdata; 193 const struct cifsTconInfo *tcon = cookie_netfs_data; 194 195 if (datalen != sizeof(auxdata)) 196 return FSCACHE_CHECKAUX_OBSOLETE; 197 198 memset(&auxdata, 0, sizeof(auxdata)); 199 auxdata.resource_id = tcon->resource_id; 200 201 if (memcmp(data, &auxdata, datalen) != 0) 202 return FSCACHE_CHECKAUX_OBSOLETE; 203 204 return FSCACHE_CHECKAUX_OKAY; 205} 206 207/* 208 * Superblock object for FS-Cache 209 */ 210const struct fscache_cookie_def cifs_fscache_super_index_def = { 211 .name = "CIFS.super", 212 .type = FSCACHE_COOKIE_TYPE_INDEX, 213 .get_key = cifs_super_get_key, 214 .get_aux = cifs_fscache_super_get_aux, 215 .check_aux = cifs_fscache_super_check_aux, 216}; 217 218/* 219 * Auxiliary data attached to CIFS inode within the cache 220 */ 221struct cifs_fscache_inode_auxdata { 222 struct timespec last_write_time; 223 struct timespec last_change_time; 224 u64 eof; 225}; 226 227static uint16_t cifs_fscache_inode_get_key(const void *cookie_netfs_data, 228 void *buffer, uint16_t maxbuf) 229{ 230 const struct cifsInodeInfo *cifsi = cookie_netfs_data; 231 uint16_t keylen; 232 233 /* use the UniqueId as the key */ 234 keylen = sizeof(cifsi->uniqueid); 235 if (keylen > maxbuf) 236 keylen = 0; 237 else 238 memcpy(buffer, &cifsi->uniqueid, keylen); 239 240 return keylen; 241} 242 243static void 244cifs_fscache_inode_get_attr(const void *cookie_netfs_data, uint64_t *size) 245{ 246 const struct cifsInodeInfo *cifsi = cookie_netfs_data; 247 248 *size = cifsi->vfs_inode.i_size; 249} 250 251static uint16_t 252cifs_fscache_inode_get_aux(const void *cookie_netfs_data, void *buffer, 253 uint16_t maxbuf) 254{ 255 struct cifs_fscache_inode_auxdata auxdata; 256 const struct cifsInodeInfo *cifsi = cookie_netfs_data; 257 258 memset(&auxdata, 0, sizeof(auxdata)); 259 auxdata.eof = cifsi->server_eof; 260 auxdata.last_write_time = cifsi->vfs_inode.i_mtime; 261 auxdata.last_change_time = cifsi->vfs_inode.i_ctime; 262 263 if (maxbuf > sizeof(auxdata)) 264 maxbuf = sizeof(auxdata); 265 266 memcpy(buffer, &auxdata, maxbuf); 267 268 return maxbuf; 269} 270 271static enum 272fscache_checkaux cifs_fscache_inode_check_aux(void *cookie_netfs_data, 273 const void *data, 274 uint16_t datalen) 275{ 276 struct cifs_fscache_inode_auxdata auxdata; 277 struct cifsInodeInfo *cifsi = cookie_netfs_data; 278 279 if (datalen != sizeof(auxdata)) 280 return FSCACHE_CHECKAUX_OBSOLETE; 281 282 memset(&auxdata, 0, sizeof(auxdata)); 283 auxdata.eof = cifsi->server_eof; 284 auxdata.last_write_time = cifsi->vfs_inode.i_mtime; 285 auxdata.last_change_time = cifsi->vfs_inode.i_ctime; 286 287 if (memcmp(data, &auxdata, datalen) != 0) 288 return FSCACHE_CHECKAUX_OBSOLETE; 289 290 return FSCACHE_CHECKAUX_OKAY; 291} 292 293static void cifs_fscache_inode_now_uncached(void *cookie_netfs_data) 294{ 295 struct cifsInodeInfo *cifsi = cookie_netfs_data; 296 struct pagevec pvec; 297 pgoff_t first; 298 int loop, nr_pages; 299 300 pagevec_init(&pvec, 0); 301 first = 0; 302 303 cFYI(1, "cifs inode 0x%p now uncached", cifsi); 304 305 for (;;) { 306 nr_pages = pagevec_lookup(&pvec, 307 cifsi->vfs_inode.i_mapping, first, 308 PAGEVEC_SIZE - pagevec_count(&pvec)); 309 if (!nr_pages) 310 break; 311 312 for (loop = 0; loop < nr_pages; loop++) 313 ClearPageFsCache(pvec.pages[loop]); 314 315 first = pvec.pages[nr_pages - 1]->index + 1; 316 317 pvec.nr = nr_pages; 318 pagevec_release(&pvec); 319 cond_resched(); 320 } 321} 322 323const struct fscache_cookie_def cifs_fscache_inode_object_def = { 324 .name = "CIFS.uniqueid", 325 .type = FSCACHE_COOKIE_TYPE_DATAFILE, 326 .get_key = cifs_fscache_inode_get_key, 327 .get_attr = cifs_fscache_inode_get_attr, 328 .get_aux = cifs_fscache_inode_get_aux, 329 .check_aux = cifs_fscache_inode_check_aux, 330 .now_uncached = cifs_fscache_inode_now_uncached, 331}; 332