LXR linux/fs/cifs/cache.c

   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 * Server object for FS-Cache
  50 */
  51const struct fscache_cookie_def cifs_fscache_server_index_def = {
  52        .name = "CIFS.server",
  53        .type = FSCACHE_COOKIE_TYPE_INDEX,
  54};
  55
  56static enum
  57fscache_checkaux cifs_fscache_super_check_aux(void *cookie_netfs_data,
  58                                              const void *data,
  59                                              uint16_t datalen,
  60                                              loff_t object_size)
  61{
  62        struct cifs_fscache_super_auxdata auxdata;
  63        const struct cifs_tcon *tcon = cookie_netfs_data;
  64
  65        if (datalen != sizeof(auxdata))
  66                return FSCACHE_CHECKAUX_OBSOLETE;
  67
  68        memset(&auxdata, 0, sizeof(auxdata));
  69        auxdata.resource_id = tcon->resource_id;
  70        auxdata.vol_create_time = tcon->vol_create_time;
  71        auxdata.vol_serial_number = tcon->vol_serial_number;
  72
  73        if (memcmp(data, &auxdata, datalen) != 0)
  74                return FSCACHE_CHECKAUX_OBSOLETE;
  75
  76        return FSCACHE_CHECKAUX_OKAY;
  77}
  78
  79/*
  80 * Superblock object for FS-Cache
  81 */
  82const struct fscache_cookie_def cifs_fscache_super_index_def = {
  83        .name = "CIFS.super",
  84        .type = FSCACHE_COOKIE_TYPE_INDEX,
  85        .check_aux = cifs_fscache_super_check_aux,
  86};
  87
  88static enum
  89fscache_checkaux cifs_fscache_inode_check_aux(void *cookie_netfs_data,
  90                                              const void *data,
  91                                              uint16_t datalen,
  92                                              loff_t object_size)
  93{
  94        struct cifs_fscache_inode_auxdata auxdata;
  95        struct cifsInodeInfo *cifsi = cookie_netfs_data;
  96
  97        if (datalen != sizeof(auxdata))
  98                return FSCACHE_CHECKAUX_OBSOLETE;
  99
 100        memset(&auxdata, 0, sizeof(auxdata));
 101        auxdata.eof = cifsi->server_eof;
 102        auxdata.last_write_time_sec = cifsi->vfs_inode.i_mtime.tv_sec;
 103        auxdata.last_change_time_sec = cifsi->vfs_inode.i_ctime.tv_sec;
 104        auxdata.last_write_time_nsec = cifsi->vfs_inode.i_mtime.tv_nsec;
 105        auxdata.last_change_time_nsec = cifsi->vfs_inode.i_ctime.tv_nsec;
 106
 107        if (memcmp(data, &auxdata, datalen) != 0)
 108                return FSCACHE_CHECKAUX_OBSOLETE;
 109
 110        return FSCACHE_CHECKAUX_OKAY;
 111}
 112
 113const struct fscache_cookie_def cifs_fscache_inode_object_def = {
 114        .name           = "CIFS.uniqueid",
 115        .type           = FSCACHE_COOKIE_TYPE_DATAFILE,
 116        .check_aux      = cifs_fscache_inode_check_aux,
 117};
 118