summaryrefslogtreecommitdiffstats
path: root/fs/afs/inode.c
blob: c476fde33fbc24ab64ed26137424e8eb7b7d776a (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
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
/*
 * Copyright (c) 2002 Red Hat, Inc. All rights reserved.
 *
 * This software may be freely redistributed under the terms of the
 * GNU General Public License.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * Authors: David Woodhouse <dwmw2@cambridge.redhat.com>
 *          David Howells <dhowells@redhat.com>
 *
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/pagemap.h>
#include "volume.h"
#include "vnode.h"
#include "super.h"
#include "internal.h"

struct afs_iget_data {
	struct afs_fid		fid;
	struct afs_volume	*volume;	/* volume on which resides */
};

/*****************************************************************************/
/*
 * map the AFS file status to the inode member variables
 */
static int afs_inode_map_status(struct afs_vnode *vnode)
{
	struct inode *inode = AFS_VNODE_TO_I(vnode);

	_debug("FS: ft=%d lk=%d sz=%Zu ver=%Lu mod=%hu",
	       vnode->status.type,
	       vnode->status.nlink,
	       vnode->status.size,
	       vnode->status.version,
	       vnode->status.mode);

	switch (vnode->status.type) {
	case AFS_FTYPE_FILE:
		inode->i_mode	= S_IFREG | vnode->status.mode;
		inode->i_op	= &afs_file_inode_operations;
		inode->i_fop	= &afs_file_file_operations;
		break;
	case AFS_FTYPE_DIR:
		inode->i_mode	= S_IFDIR | vnode->status.mode;
		inode->i_op	= &afs_dir_inode_operations;
		inode->i_fop	= &afs_dir_file_operations;
		break;
	case AFS_FTYPE_SYMLINK:
		inode->i_mode	= S_IFLNK | vnode->status.mode;
		inode->i_op	= &page_symlink_inode_operations;
		break;
	default:
		printk("kAFS: AFS vnode with undefined type\n");
		return -EBADMSG;
	}

	inode->i_nlink		= vnode->status.nlink;
	inode->i_uid		= vnode->status.owner;
	inode->i_gid		= 0;
	inode->i_size		= vnode->status.size;
	inode->i_ctime.tv_sec	= vnode->status.mtime_server;
	inode->i_ctime.tv_nsec	= 0;
	inode->i_atime		= inode->i_mtime = inode->i_ctime;
	inode->i_blksize	= PAGE_CACHE_SIZE;
	inode->i_blocks		= 0;
	inode->i_version	= vnode->fid.unique;
	inode->i_mapping->a_ops	= &afs_fs_aops;

	/* check to see whether a symbolic link is really a mountpoint */
	if (vnode->status.type == AFS_FTYPE_SYMLINK) {
		afs_mntpt_check_symlink(vnode);

		if (vnode->flags & AFS_VNODE_MOUNTPOINT) {
			inode->i_mode	= S_IFDIR | vnode->status.mode;
			inode->i_op	= &afs_mntpt_inode_operations;
			inode->i_fop	= &afs_mntpt_file_operations;
		}
	}

	return 0;
} /* end afs_inode_map_status() */

/*****************************************************************************/
/*
 * attempt to fetch the status of an inode, coelescing multiple simultaneous
 * fetches
 */
static int afs_inode_fetch_status(struct inode *inode)
{
	struct afs_vnode *vnode;
	int ret;

	vnode = AFS_FS_I(inode);

	ret = afs_vnode_fetch_status(vnode);

	if (ret == 0)
		ret = afs_inode_map_status(vnode);

	return ret;

} /* end afs_inode_fetch_status() */

/*****************************************************************************/
/*
 * iget5() comparator
 */
static int afs_iget5_test(struct inode *inode, void *opaque)
{
	struct afs_iget_data *data = opaque;

	return inode->i_ino == data->fid.vnode &&
		inode->i_version == data->fid.unique;
} /* end afs_iget5_test() */

/*****************************************************************************/
/*
 * iget5() inode initialiser
 */
static int afs_iget5_set(struct inode *inode, void *opaque)
{
	struct afs_iget_data *data = opaque;
	struct afs_vnode *vnode = AFS_FS_I(inode);

	inode->i_ino = data->fid.vnode;
	inode->i_version = data->fid.unique;
	vnode->fid = data->fid;
	vnode->volume = data->volume;

	return 0;
} /* end afs_iget5_set() */

/*****************************************************************************/
/*
 * inode retrieval
 */
inline int afs_iget(struct super_block *sb, struct afs_fid *fid,
		    struct inode **_inode)
{
	struct afs_iget_data data = { .fid = *fid };
	struct afs_super_info *as;
	struct afs_vnode *vnode;
	struct inode *inode;
	int ret;

	_enter(",{%u,%u,%u},,", fid->vid, fid->vnode, fid->unique);

	as = sb->s_fs_info;
	data.volume = as->volume;

	inode = iget5_locked(sb, fid->vnode, afs_iget5_test, afs_iget5_set,
			     &data);
	if (!inode) {
		_leave(" = -ENOMEM");
		return -ENOMEM;
	}

	vnode = AFS_FS_I(inode);

	/* deal with an existing inode */
	if (!(inode->i_state & I_NEW)) {
		ret = afs_vnode_fetch_status(vnode);
		if (ret==0)
			*_inode = inode;
		else
			iput(inode);
		_leave(" = %d", ret);
		return ret;
	}

#ifdef AFS_CACHING_SUPPORT
	/* set up caching before reading the status, as fetch-status reads the
	 * first page of symlinks to see if they're really mntpts */
	cachefs_acquire_cookie(vnode->volume->cache,
			       NULL,
			       vnode,
			       &vnode->cache);
#endif

	/* okay... it's a new inode */
	inode->i_flags |= S_NOATIME;
	vnode->flags |= AFS_VNODE_CHANGED;
	ret = afs_inode_fetch_status(inode);
	if (ret<0)
		goto bad_inode;

	/* success */
	unlock_new_inode(inode);

	*_inode = inode;
	_leave(" = 0 [CB { v=%u x=%lu t=%u }]",
	       vnode->cb_version,
	       vnode->cb_timeout.timo_jif,
	       vnode->cb_type);
	return 0;

	/* failure */
 bad_inode:
	make_bad_inode(inode);
	unlock_new_inode(inode);
	iput(inode);

	_leave(" = %d [bad]", ret);
	return ret;
} /* end afs_iget() */

/*****************************************************************************/
/*
 * read the attributes of an inode
 */
int afs_inode_getattr(struct vfsmount *mnt, struct dentry *dentry,
		      struct kstat *stat)
{
	struct afs_vnode *vnode;
	struct inode *inode;
	int ret;

	inode = dentry->d_inode;

	_enter("{ ino=%lu v=%lu }", inode->i_ino, inode->i_version);

	vnode = AFS_FS_I(inode);

	ret = afs_inode_fetch_status(inode);
	if (ret == -ENOENT) {
		_leave(" = %d [%d %p]",
		       ret, atomic_read(&dentry->d_count), dentry->d_inode);
		return ret;
	}
	else if (ret < 0) {
		make_bad_inode(inode);
		_leave(" = %d", ret);
		return ret;
	}

	/* transfer attributes from the inode structure to the stat
	 * structure */
	generic_fillattr(inode, stat);

	_leave(" = 0 CB { v=%u x=%u t=%u }",
	       vnode->cb_version,
	       vnode->cb_expiry,
	       vnode->cb_type);

	return 0;
} /* end afs_inode_getattr() */

/*****************************************************************************/
/*
 * clear an AFS inode
 */
void afs_clear_inode(struct inode *inode)
{
	struct afs_vnode *vnode;

	vnode = AFS_FS_I(inode);

	_enter("ino=%lu { vn=%08x v=%u x=%u t=%u }",
	       inode->i_ino,
	       vnode->fid.vnode,
	       vnode->cb_version,
	       vnode->cb_expiry,
	       vnode->cb_type
	       );

	BUG_ON(inode->i_ino != vnode->fid.vnode);

	afs_vnode_give_up_callback(vnode);

#ifdef AFS_CACHING_SUPPORT
	cachefs_relinquish_cookie(vnode->cache, 0);
	vnode->cache = NULL;
#endif

	_leave("");
} /* end afs_clear_inode() */