summaryrefslogtreecommitdiff
path: root/fs/cifs/fscache.c
blob: efaac4d5ff5570125fa5e6df33312b3604657e42 (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
// SPDX-License-Identifier: LGPL-2.1
/*
 *   CIFS filesystem cache interface
 *
 *   Copyright (c) 2010 Novell, Inc.
 *   Author(s): Suresh Jayaraman <sjayaraman@suse.de>
 *
 */
#include "fscache.h"
#include "cifsglob.h"
#include "cifs_debug.h"
#include "cifs_fs_sb.h"
#include "cifsproto.h"

static void cifs_fscache_fill_volume_coherency(
	struct cifs_tcon *tcon,
	struct cifs_fscache_volume_coherency_data *cd)
{
	memset(cd, 0, sizeof(*cd));
	cd->resource_id		= cpu_to_le64(tcon->resource_id);
	cd->vol_create_time	= tcon->vol_create_time;
	cd->vol_serial_number	= cpu_to_le32(tcon->vol_serial_number);
}

int cifs_fscache_get_super_cookie(struct cifs_tcon *tcon)
{
	struct cifs_fscache_volume_coherency_data cd;
	struct TCP_Server_Info *server = tcon->ses->server;
	struct fscache_volume *vcookie;
	const struct sockaddr *sa = (struct sockaddr *)&server->dstaddr;
	size_t slen, i;
	char *sharename;
	char *key;
	int ret = -ENOMEM;

	tcon->fscache = NULL;
	switch (sa->sa_family) {
	case AF_INET:
	case AF_INET6:
		break;
	default:
		cifs_dbg(VFS, "Unknown network family '%d'\n", sa->sa_family);
		return -EINVAL;
	}

	memset(&key, 0, sizeof(key));

	sharename = extract_sharename(tcon->treeName);
	if (IS_ERR(sharename)) {
		cifs_dbg(FYI, "%s: couldn't extract sharename\n", __func__);
		return -EINVAL;
	}

	slen = strlen(sharename);
	for (i = 0; i < slen; i++)
		if (sharename[i] == '/')
			sharename[i] = ';';

	key = kasprintf(GFP_KERNEL, "cifs,%pISpc,%s", sa, sharename);
	if (!key)
		goto out;

	cifs_fscache_fill_volume_coherency(tcon, &cd);
	vcookie = fscache_acquire_volume(key,
					 NULL, /* preferred_cache */
					 &cd, sizeof(cd));
	cifs_dbg(FYI, "%s: (%s/0x%p)\n", __func__, key, vcookie);
	if (IS_ERR(vcookie)) {
		if (vcookie != ERR_PTR(-EBUSY)) {
			ret = PTR_ERR(vcookie);
			goto out_2;
		}
		pr_err("Cache volume key already in use (%s)\n", key);
		vcookie = NULL;
	}

	tcon->fscache = vcookie;
	ret = 0;
out_2:
	kfree(key);
out:
	kfree(sharename);
	return ret;
}

void cifs_fscache_release_super_cookie(struct cifs_tcon *tcon)
{
	struct cifs_fscache_volume_coherency_data cd;

	cifs_dbg(FYI, "%s: (0x%p)\n", __func__, tcon->fscache);

	cifs_fscache_fill_volume_coherency(tcon, &cd);
	fscache_relinquish_volume(tcon->fscache, &cd, false);
	tcon->fscache = NULL;
}

void cifs_fscache_get_inode_cookie(struct inode *inode)
{
	struct cifs_fscache_inode_coherency_data cd;
	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);

	cifs_fscache_fill_coherency(&cifsi->vfs_inode, &cd);

	cifsi->fscache =
		fscache_acquire_cookie(tcon->fscache, 0,
				       &cifsi->uniqueid, sizeof(cifsi->uniqueid),
				       &cd, sizeof(cd),
				       i_size_read(&cifsi->vfs_inode));
}

void cifs_fscache_unuse_inode_cookie(struct inode *inode, bool update)
{
	if (update) {
		struct cifs_fscache_inode_coherency_data cd;
		loff_t i_size = i_size_read(inode);

		cifs_fscache_fill_coherency(inode, &cd);
		fscache_unuse_cookie(cifs_inode_cookie(inode), &cd, &i_size);
	} else {
		fscache_unuse_cookie(cifs_inode_cookie(inode), NULL, NULL);
	}
}

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

	if (cifsi->fscache) {
		cifs_dbg(FYI, "%s: (0x%p)\n", __func__, cifsi->fscache);
		fscache_relinquish_cookie(cifsi->fscache, false);
		cifsi->fscache = NULL;
	}
}

/*
 * Retrieve a page from FS-Cache
 */
int __cifs_readpage_from_fscache(struct inode *inode, struct page *page)
{
	cifs_dbg(FYI, "%s: (fsc:%p, p:%p, i:0x%p\n",
		 __func__, CIFS_I(inode)->fscache, page, inode);
	return -ENOBUFS; // Needs conversion to using netfslib
}

/*
 * 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)
{
	cifs_dbg(FYI, "%s: (0x%p/%u/0x%p)\n",
		 __func__, CIFS_I(inode)->fscache, *nr_pages, inode);
	return -ENOBUFS; // Needs conversion to using netfslib
}

void __cifs_readpage_to_fscache(struct inode *inode, struct page *page)
{
	struct cifsInodeInfo *cifsi = CIFS_I(inode);

	WARN_ON(!cifsi->fscache);

	cifs_dbg(FYI, "%s: (fsc: %p, p: %p, i: %p)\n",
		 __func__, cifsi->fscache, page, inode);

	// Needs conversion to using netfslib
}