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
 56char *extract_sharename(const char *treename)
 57{
 58	const char *src;
 59	char *delim, *dst;
 60	int len;
 61
 62	/* skip double chars at the beginning */
 63	src = treename + 2;
 64
 65	/* share name is always preceded by '\\' now */
 66	delim = strchr(src, '\\');
 67	if (!delim)
 68		return ERR_PTR(-EINVAL);
 69	delim++;
 70	len = strlen(delim);
 71
 72	/* caller has to free the memory */
 73	dst = kstrndup(delim, len, GFP_KERNEL);
 74	if (!dst)
 75		return ERR_PTR(-ENOMEM);
 76
 77	return dst;
 78}
 79
 80static enum
 81fscache_checkaux cifs_fscache_super_check_aux(void *cookie_netfs_data,
 82					      const void *data,
 83					      uint16_t datalen,
 84					      loff_t object_size)
 85{
 86	struct cifs_fscache_super_auxdata auxdata;
 87	const struct cifs_tcon *tcon = cookie_netfs_data;
 88
 89	if (datalen != sizeof(auxdata))
 90		return FSCACHE_CHECKAUX_OBSOLETE;
 91
 92	memset(&auxdata, 0, sizeof(auxdata));
 93	auxdata.resource_id = tcon->resource_id;
 94	auxdata.vol_create_time = tcon->vol_create_time;
 95	auxdata.vol_serial_number = tcon->vol_serial_number;
 96
 97	if (memcmp(data, &auxdata, datalen) != 0)
 98		return FSCACHE_CHECKAUX_OBSOLETE;
 99
100	return FSCACHE_CHECKAUX_OKAY;
101}
102
103/*
104 * Superblock object for FS-Cache
105 */
106const struct fscache_cookie_def cifs_fscache_super_index_def = {
107	.name = "CIFS.super",
108	.type = FSCACHE_COOKIE_TYPE_INDEX,
109	.check_aux = cifs_fscache_super_check_aux,
110};
111
112static enum
113fscache_checkaux cifs_fscache_inode_check_aux(void *cookie_netfs_data,
114					      const void *data,
115					      uint16_t datalen,
116					      loff_t object_size)
117{
118	struct cifs_fscache_inode_auxdata auxdata;
119	struct cifsInodeInfo *cifsi = cookie_netfs_data;
120
121	if (datalen != sizeof(auxdata))
122		return FSCACHE_CHECKAUX_OBSOLETE;
123
124	memset(&auxdata, 0, sizeof(auxdata));
125	auxdata.eof = cifsi->server_eof;
126	auxdata.last_write_time_sec = cifsi->vfs_inode.i_mtime.tv_sec;
127	auxdata.last_change_time_sec = cifsi->vfs_inode.i_ctime.tv_sec;
128	auxdata.last_write_time_nsec = cifsi->vfs_inode.i_mtime.tv_nsec;
129	auxdata.last_change_time_nsec = cifsi->vfs_inode.i_ctime.tv_nsec;
130
131	if (memcmp(data, &auxdata, datalen) != 0)
132		return FSCACHE_CHECKAUX_OBSOLETE;
133
134	return FSCACHE_CHECKAUX_OKAY;
135}
136
137const struct fscache_cookie_def cifs_fscache_inode_object_def = {
138	.name		= "CIFS.uniqueid",
139	.type		= FSCACHE_COOKIE_TYPE_DATAFILE,
140	.check_aux	= cifs_fscache_inode_check_aux,
141};