diff options
Diffstat (limited to 'fs/cifs/cache.c')
| -rw-r--r-- | fs/cifs/cache.c | 146 |
1 files changed, 146 insertions, 0 deletions
diff --git a/fs/cifs/cache.c b/fs/cifs/cache.c new file mode 100644 index 000000000..b7420e605 --- /dev/null +++ b/fs/cifs/cache.c @@ -0,0 +1,146 @@ +/* + * fs/cifs/cache.c - CIFS filesystem cache index structure definitions + * + * Copyright (c) 2010 Novell, Inc. + * Authors(s): Suresh Jayaraman (sjayaraman@suse.de> + * + * This library is free software; you can redistribute it and/or modify + * it under the terms of the GNU Lesser General Public License as published + * by the Free Software Foundation; either version 2.1 of the License, or + * (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See + * the GNU Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public License + * along with this library; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ +#include "fscache.h" +#include "cifs_debug.h" + +/* + * CIFS filesystem definition for FS-Cache + */ +struct fscache_netfs cifs_fscache_netfs = { + .name = "cifs", + .version = 0, +}; + +/* + * Register CIFS for caching with FS-Cache + */ +int cifs_fscache_register(void) +{ + return fscache_register_netfs(&cifs_fscache_netfs); +} + +/* + * Unregister CIFS for caching + */ +void cifs_fscache_unregister(void) +{ + fscache_unregister_netfs(&cifs_fscache_netfs); +} + +/* + * Server object for FS-Cache + */ +const struct fscache_cookie_def cifs_fscache_server_index_def = { + .name = "CIFS.server", + .type = FSCACHE_COOKIE_TYPE_INDEX, +}; + +/* + * Auxiliary data attached to CIFS superblock within the cache + */ +struct cifs_fscache_super_auxdata { + u64 resource_id; /* unique server resource id */ +}; + +char *extract_sharename(const char *treename) +{ + const char *src; + char *delim, *dst; + int len; + + /* skip double chars at the beginning */ + src = treename + 2; + + /* share name is always preceded by '\\' now */ + delim = strchr(src, '\\'); + if (!delim) + return ERR_PTR(-EINVAL); + delim++; + len = strlen(delim); + + /* caller has to free the memory */ + dst = kstrndup(delim, len, GFP_KERNEL); + if (!dst) + return ERR_PTR(-ENOMEM); + + return dst; +} + +static enum +fscache_checkaux cifs_fscache_super_check_aux(void *cookie_netfs_data, + const void *data, + uint16_t datalen, + loff_t object_size) +{ + struct cifs_fscache_super_auxdata auxdata; + const struct cifs_tcon *tcon = cookie_netfs_data; + + if (datalen != sizeof(auxdata)) + return FSCACHE_CHECKAUX_OBSOLETE; + + memset(&auxdata, 0, sizeof(auxdata)); + auxdata.resource_id = tcon->resource_id; + + if (memcmp(data, &auxdata, datalen) != 0) + return FSCACHE_CHECKAUX_OBSOLETE; + + return FSCACHE_CHECKAUX_OKAY; +} + +/* + * Superblock object for FS-Cache + */ +const struct fscache_cookie_def cifs_fscache_super_index_def = { + .name = "CIFS.super", + .type = FSCACHE_COOKIE_TYPE_INDEX, + .check_aux = cifs_fscache_super_check_aux, +}; + +static enum +fscache_checkaux cifs_fscache_inode_check_aux(void *cookie_netfs_data, + const void *data, + uint16_t datalen, + loff_t object_size) +{ + struct cifs_fscache_inode_auxdata auxdata; + struct cifsInodeInfo *cifsi = cookie_netfs_data; + + if (datalen != sizeof(auxdata)) + return FSCACHE_CHECKAUX_OBSOLETE; + + memset(&auxdata, 0, sizeof(auxdata)); + auxdata.eof = cifsi->server_eof; + auxdata.last_write_time_sec = cifsi->vfs_inode.i_mtime.tv_sec; + auxdata.last_change_time_sec = cifsi->vfs_inode.i_ctime.tv_sec; + auxdata.last_write_time_nsec = cifsi->vfs_inode.i_mtime.tv_nsec; + auxdata.last_change_time_nsec = cifsi->vfs_inode.i_ctime.tv_nsec; + + if (memcmp(data, &auxdata, datalen) != 0) + return FSCACHE_CHECKAUX_OBSOLETE; + + return FSCACHE_CHECKAUX_OKAY; +} + +const struct fscache_cookie_def cifs_fscache_inode_object_def = { + .name = "CIFS.uniqueid", + .type = FSCACHE_COOKIE_TYPE_DATAFILE, + .check_aux = cifs_fscache_inode_check_aux, +}; |