aboutsummaryrefslogtreecommitdiff
path: root/fs/cifs/fscache.c
blob: d368a47ba5ebf317b377a0c34b0aeb2938a6c871 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
/*
 *   fs/cifs/fscache.c - CIFS filesystem cache interface
 *
 *   Copyright (c) 2010 Novell, Inc.
 *   Author(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 "cifsglob.h"
#include "cifs_debug.h"
#include "cifs_fs_sb.h"

void cifs_fscache_get_client_cookie(struct TCP_Server_Info *server)
{
	server->fscache =
		fscache_acquire_cookie(cifs_fscache_netfs.primary_index,
				&cifs_fscache_server_index_def, server);
	cFYI(1, "CIFS: get client cookie (0x%p/0x%p)", server,
				server->fscache);
}

void cifs_fscache_release_client_cookie(struct TCP_Server_Info *server)
{
	cFYI(1, "CIFS: release client cookie (0x%p/0x%p)", server,
				server->fscache);
	fscache_relinquish_cookie(server->fscache, 0);
	server->fscache = NULL;
}

void cifs_fscache_get_super_cookie(struct cifs_tcon *tcon)
{
	struct TCP_Server_Info *server = tcon->ses->server;

	tcon->fscache =
		fscache_acquire_cookie(server->fscache,
				&cifs_fscache_super_index_def, tcon);
	cFYI(1, "CIFS: get superblock cookie (0x%p/0x%p)",
				server->fscache, tcon->fscache);
}

void cifs_fscache_release_super_cookie(struct cifs_tcon *tcon)
{
	cFYI(1, "CIFS: releasing superblock cookie (0x%p)", tcon->fscache);
	fscache_relinquish_cookie(tcon->fscache, 0);
	tcon->fscache = NULL;
}

static void cifs_fscache_enable_inode_cookie(struct inode *inode)
{
	struct cifsInodeInfo *cifsi = CIFS_I(inode);
	struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
	struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);

	if (cifsi->fscache)
		return;

	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_FSCACHE) {
		cifsi->fscache = fscache_acquire_cookie(tcon->fscache,
				&cifs_fscache_inode_object_def, cifsi);
		cFYI(1, "CIFS: got FH cookie (0x%p/0x%p)", tcon->fscache,
				cifsi->fscache);
	}
}

void cifs_fscache_release_inode_cookie(struct inode *inode)
{
	struct cifsInodeInfo *cifsi = CIFS_I(inode);

	if (cifsi->fscache) {
		cFYI(1, "CIFS releasing inode cookie (0x%p)",
				cifsi->fscache);
		fscache_relinquish_cookie(cifsi->fscache, 0);
		cifsi->fscache = NULL;
	}
}

static void cifs_fscache_disable_inode_cookie(struct inode *inode)
{
	struct cifsInodeInfo *cifsi = CIFS_I(inode);

	if (cifsi->fscache) {
		cFYI(1, "CIFS disabling inode cookie (0x%p)",
				cifsi->fscache);
		fscache_relinquish_cookie(cifsi->fscache, 1);
		cifsi->fscache = NULL;
	}
}

void cifs_fscache_set_inode_cookie(struct inode *inode, struct file *filp)
{
	if ((filp->f_flags & O_ACCMODE) != O_RDONLY)
		cifs_fscache_disable_inode_cookie(inode);
	else
		cifs_fscache_enable_inode_cookie(inode);
}

void cifs_fscache_reset_inode_cookie(struct inode *inode)
{
	struct cifsInodeInfo *cifsi = CIFS_I(inode);
	struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
	struct fscache_cookie *old = cifsi->fscache;

	if (cifsi->fscache) {
		/* retire the current fscache cache and get a new one */
		fscache_relinquish_cookie(cifsi->fscache, 1);

		cifsi->fscache = fscache_acquire_cookie(
					cifs_sb_master_tcon(cifs_sb)->fscache,
					&cifs_fscache_inode_object_def,
					cifsi);
		cFYI(1, "CIFS: new cookie 0x%p oldcookie 0x%p",
				cifsi->fscache, old);
	}
}

int cifs_fscache_release_page(struct page *page, gfp_t gfp)
{
	if (PageFsCache(page)) {
		struct inode *inode = page->mapping->host;
		struct cifsInodeInfo *cifsi = CIFS_I(inode);

		cFYI(1, "CIFS: fscache release page (0x%p/0x%p)",
				page, cifsi->fscache);
		if (!fscache_maybe_release_page(cifsi->fscache, page, gfp))
			return 0;
	}

	return 1;
}

static void cifs_readpage_from_fscache_complete(struct page *page, void *ctx,
						int error)
{
	cFYI(1, "CFS: readpage_from_fscache_complete (0x%p/%d)",
			page, error);
	if (!error)
		SetPageUptodate(page);
	unlock_page(page);
}

/*
 * Retrieve a page from FS-Cache
 */
int __cifs_readpage_from_fscache(struct inode *inode, struct page *page)
{
	int ret;

	cFYI(1, "CIFS: readpage_from_fscache(fsc:%p, p:%p, i:0x%p",
			CIFS_I(inode)->fscache, page, inode);
	ret = fscache_read_or_alloc_page(CIFS_I(inode)->fscache, page,
					 cifs_readpage_from_fscache_complete,
					 NULL,
					 GFP_KERNEL);
	switch (ret) {

	case 0: /* page found in fscache, read submitted */
		cFYI(1, "CIFS: readpage_from_fscache: submitted");
		return ret;
	case -ENOBUFS:	/* page won't be cached */
	case -ENODATA:	/* page not in cache */
		cFYI(1, "CIFS: readpage_from_fscache %d", ret);
		return 1;

	default:
		cERROR(1, "unknown error ret = %d", ret);
	}
	return ret;
}

/*
 * Retrieve a set of pages from FS-Cache
 */
int __cifs_readpages_from_fscache(struct inode *inode,
				struct address_space *mapping,
				struct list_head *pages,
				unsigned *nr_pages)
{
	int ret;

	cFYI(1, "CIFS: __cifs_readpages_from_fscache (0x%p/%u/0x%p)",
			CIFS_I(inode)->fscache, *nr_pages, inode);
	ret = fscache_read_or_alloc_pages(CIFS_I(inode)->fscache, mapping,
					  pages, nr_pages,
					  cifs_readpage_from_fscache_complete,
					  NULL,
					  mapping_gfp_mask(mapping));
	switch (ret) {
	case 0:	/* read submitted to the cache for all pages */
		cFYI(1, "CIFS: readpages_from_fscache: submitted");
		return ret;

	case -ENOBUFS:	/* some pages are not cached and can't be */
	case -ENODATA:	/* some pages are not cached */
		cFYI(1, "CIFS: readpages_from_fscache: no page");
		return 1;

	default:
		cFYI(1, "unknown error ret = %d", ret);
	}

	return ret;
}

void __cifs_readpage_to_fscache(struct inode *inode, struct page *page)
{
	int ret;

	cFYI(1, "CIFS: readpage_to_fscache(fsc: %p, p: %p, i: %p",
			CIFS_I(inode)->fscache, page, inode);
	ret = fscache_write_page(CIFS_I(inode)->fscache, page, GFP_KERNEL);
	if (ret != 0)
		fscache_uncache_page(CIFS_I(inode)->fscache, page);
}

void __cifs_fscache_invalidate_page(struct page *page, struct inode *inode)
{
	struct cifsInodeInfo *cifsi = CIFS_I(inode);
	struct fscache_cookie *cookie = cifsi->fscache;

	cFYI(1, "CIFS: fscache invalidatepage (0x%p/0x%p)", page, cookie);
	fscache_wait_on_page_write(cookie, page);
	fscache_uncache_page(cookie, page);
}