1/*
2 * Copyright (c) 2000-2001 Christoph Hellwig.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions, and the following disclaimer,
10 *    without modification.
11 * 2. The name of the author may not be used to endorse or promote products
12 *    derived from this software without specific prior written permission.
13 *
14 * Alternatively, this software may be distributed under the terms of the
15 * GNU General Public License ("GPL").
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
21 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30/*
31 * Veritas filesystem driver - superblock related routines.
32 */
33#include <linux/init.h>
34#include <linux/module.h>
35
36#include <linux/blkdev.h>
37#include <linux/fs.h>
38#include <linux/buffer_head.h>
39#include <linux/kernel.h>
40#include <linux/slab.h>
41#include <linux/stat.h>
42#include <linux/vfs.h>
43#include <linux/mount.h>
44
45#include "vxfs.h"
46#include "vxfs_extern.h"
47#include "vxfs_dir.h"
48#include "vxfs_inode.h"
49
50
51MODULE_AUTHOR("Christoph Hellwig");
52MODULE_DESCRIPTION("Veritas Filesystem (VxFS) driver");
53MODULE_LICENSE("Dual BSD/GPL");
54
55
56
57static void		vxfs_put_super(struct super_block *);
58static int		vxfs_statfs(struct dentry *, struct kstatfs *);
59static int		vxfs_remount(struct super_block *, int *, char *);
60
61static const struct super_operations vxfs_super_ops = {
62	.evict_inode =		vxfs_evict_inode,
63	.put_super =		vxfs_put_super,
64	.statfs =		vxfs_statfs,
65	.remount_fs =		vxfs_remount,
66};
67
68/**
69 * vxfs_put_super - free superblock resources
70 * @sbp:	VFS superblock.
71 *
72 * Description:
73 *   vxfs_put_super frees all resources allocated for @sbp
74 *   after the last instance of the filesystem is unmounted.
75 */
76
77static void
78vxfs_put_super(struct super_block *sbp)
79{
80	struct vxfs_sb_info	*infp = VXFS_SBI(sbp);
81
82	vxfs_put_fake_inode(infp->vsi_fship);
83	vxfs_put_fake_inode(infp->vsi_ilist);
84	vxfs_put_fake_inode(infp->vsi_stilist);
85
86	brelse(infp->vsi_bp);
87	kfree(infp);
88}
89
90/**
91 * vxfs_statfs - get filesystem information
92 * @dentry:	VFS dentry to locate superblock
93 * @bufp:	output buffer
94 *
95 * Description:
96 *   vxfs_statfs fills the statfs buffer @bufp with information
97 *   about the filesystem described by @dentry.
98 *
99 * Returns:
100 *   Zero.
101 *
102 * Locking:
103 *   No locks held.
104 *
105 * Notes:
106 *   This is everything but complete...
107 */
108static int
109vxfs_statfs(struct dentry *dentry, struct kstatfs *bufp)
110{
111	struct vxfs_sb_info		*infp = VXFS_SBI(dentry->d_sb);
112
113	bufp->f_type = VXFS_SUPER_MAGIC;
114	bufp->f_bsize = dentry->d_sb->s_blocksize;
115	bufp->f_blocks = infp->vsi_raw->vs_dsize;
116	bufp->f_bfree = infp->vsi_raw->vs_free;
117	bufp->f_bavail = 0;
118	bufp->f_files = 0;
119	bufp->f_ffree = infp->vsi_raw->vs_ifree;
120	bufp->f_namelen = VXFS_NAMELEN;
121
122	return 0;
123}
124
125static int vxfs_remount(struct super_block *sb, int *flags, char *data)
126{
127	sync_filesystem(sb);
128	*flags |= MS_RDONLY;
129	return 0;
130}
131
132/**
133 * vxfs_read_super - read superblock into memory and initialize filesystem
134 * @sbp:		VFS superblock (to fill)
135 * @dp:			fs private mount data
136 * @silent:		do not complain loudly when sth is wrong
137 *
138 * Description:
139 *   We are called on the first mount of a filesystem to read the
140 *   superblock into memory and do some basic setup.
141 *
142 * Returns:
143 *   The superblock on success, else %NULL.
144 *
145 * Locking:
146 *   We are under @sbp->s_lock.
147 */
148static int vxfs_fill_super(struct super_block *sbp, void *dp, int silent)
149{
150	struct vxfs_sb_info	*infp;
151	struct vxfs_sb		*rsbp;
152	struct buffer_head	*bp = NULL;
153	u_long			bsize;
154	struct inode *root;
155	int ret = -EINVAL;
156
157	sbp->s_flags |= MS_RDONLY;
158
159	infp = kzalloc(sizeof(*infp), GFP_KERNEL);
160	if (!infp) {
161		printk(KERN_WARNING "vxfs: unable to allocate incore superblock\n");
162		return -ENOMEM;
163	}
164
165	bsize = sb_min_blocksize(sbp, BLOCK_SIZE);
166	if (!bsize) {
167		printk(KERN_WARNING "vxfs: unable to set blocksize\n");
168		goto out;
169	}
170
171	bp = sb_bread(sbp, 1);
172	if (!bp || !buffer_mapped(bp)) {
173		if (!silent) {
174			printk(KERN_WARNING
175				"vxfs: unable to read disk superblock\n");
176		}
177		goto out;
178	}
179
180	rsbp = (struct vxfs_sb *)bp->b_data;
181	if (rsbp->vs_magic != VXFS_SUPER_MAGIC) {
182		if (!silent)
183			printk(KERN_NOTICE "vxfs: WRONG superblock magic\n");
184		goto out;
185	}
186
187	if ((rsbp->vs_version < 2 || rsbp->vs_version > 4) && !silent) {
188		printk(KERN_NOTICE "vxfs: unsupported VxFS version (%d)\n",
189		       rsbp->vs_version);
190		goto out;
191	}
192
193#ifdef DIAGNOSTIC
194	printk(KERN_DEBUG "vxfs: supported VxFS version (%d)\n", rsbp->vs_version);
195	printk(KERN_DEBUG "vxfs: blocksize: %d\n", rsbp->vs_bsize);
196#endif
197
198	sbp->s_magic = rsbp->vs_magic;
199	sbp->s_fs_info = infp;
200
201	infp->vsi_raw = rsbp;
202	infp->vsi_bp = bp;
203	infp->vsi_oltext = rsbp->vs_oltext[0];
204	infp->vsi_oltsize = rsbp->vs_oltsize;
205
206	if (!sb_set_blocksize(sbp, rsbp->vs_bsize)) {
207		printk(KERN_WARNING "vxfs: unable to set final block size\n");
208		goto out;
209	}
210
211	if (vxfs_read_olt(sbp, bsize)) {
212		printk(KERN_WARNING "vxfs: unable to read olt\n");
213		goto out;
214	}
215
216	if (vxfs_read_fshead(sbp)) {
217		printk(KERN_WARNING "vxfs: unable to read fshead\n");
218		goto out;
219	}
220
221	sbp->s_op = &vxfs_super_ops;
222	root = vxfs_iget(sbp, VXFS_ROOT_INO);
223	if (IS_ERR(root)) {
224		ret = PTR_ERR(root);
225		goto out;
226	}
227	sbp->s_root = d_make_root(root);
228	if (!sbp->s_root) {
229		printk(KERN_WARNING "vxfs: unable to get root dentry.\n");
230		goto out_free_ilist;
231	}
232
233	return 0;
234
235out_free_ilist:
236	vxfs_put_fake_inode(infp->vsi_fship);
237	vxfs_put_fake_inode(infp->vsi_ilist);
238	vxfs_put_fake_inode(infp->vsi_stilist);
239out:
240	brelse(bp);
241	kfree(infp);
242	return ret;
243}
244
245/*
246 * The usual module blurb.
247 */
248static struct dentry *vxfs_mount(struct file_system_type *fs_type,
249	int flags, const char *dev_name, void *data)
250{
251	return mount_bdev(fs_type, flags, dev_name, data, vxfs_fill_super);
252}
253
254static struct file_system_type vxfs_fs_type = {
255	.owner		= THIS_MODULE,
256	.name		= "vxfs",
257	.mount		= vxfs_mount,
258	.kill_sb	= kill_block_super,
259	.fs_flags	= FS_REQUIRES_DEV,
260};
261MODULE_ALIAS_FS("vxfs"); /* makes mount -t vxfs autoload the module */
262MODULE_ALIAS("vxfs");
263
264static int __init
265vxfs_init(void)
266{
267	int rv;
268
269	vxfs_inode_cachep = kmem_cache_create("vxfs_inode",
270			sizeof(struct vxfs_inode_info), 0,
271			SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD, NULL);
272	if (!vxfs_inode_cachep)
273		return -ENOMEM;
274	rv = register_filesystem(&vxfs_fs_type);
275	if (rv < 0)
276		kmem_cache_destroy(vxfs_inode_cachep);
277	return rv;
278}
279
280static void __exit
281vxfs_cleanup(void)
282{
283	unregister_filesystem(&vxfs_fs_type);
284	/*
285	 * Make sure all delayed rcu free inodes are flushed before we
286	 * destroy cache.
287	 */
288	rcu_barrier();
289	kmem_cache_destroy(vxfs_inode_cachep);
290}
291
292module_init(vxfs_init);
293module_exit(vxfs_cleanup);
294