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  */
  27 struct fscache_netfs cifs_fscache_netfs = {
  28         .name = "cifs",
  29         .version = 0,
  30 };
  31
  32 /*
  33  * Register CIFS for caching with FS-Cache
  34  */
  35 int cifs_fscache_register(void)
  36 {
  37         return fscache_register_netfs(&cifs_fscache_netfs);
  38 }
  39
  40 /*
  41  * Unregister CIFS for caching
  42  */
  43 void cifs_fscache_unregister(void)
  44 {
  45         fscache_unregister_netfs(&cifs_fscache_netfs);
  46 }
  47
  48 /*
  49  * Server object for FS-Cache
  50  */
  51 const struct fscache_cookie_def cifs_fscache_server_index_def = {
  52         .name = "CIFS.server",
  53         .type = FSCACHE_COOKIE_TYPE_INDEX,
  54 };
  55
  56 static enum
  57 fscache_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  */
  82 const 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
  88 static enum
  89 fscache_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
 113 const 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 };