1 /*
2 * Copyright (c) 2000-2001 Christoph Hellwig.
3 * Copyright (c) 2016 Krzysztof Blaszkowski
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions, and the following disclaimer,
11 * without modification.
12 * 2. The name of the author may not be used to endorse or promote products
13 * derived from this software without specific prior written permission.
14 *
15 * Alternatively, this software may be distributed under the terms of the
16 * GNU General Public License ("GPL").
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
22 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 */
30
31 /*
32 * Veritas filesystem driver - superblock related routines.
33 */
34 #include <linux/init.h>
35 #include <linux/module.h>
36
37 #include <linux/blkdev.h>
38 #include <linux/fs.h>
39 #include <linux/buffer_head.h>
40 #include <linux/kernel.h>
41 #include <linux/slab.h>
42 #include <linux/stat.h>
43 #include <linux/vfs.h>
44 #include <linux/mount.h>
45
46 #include "vxfs.h"
47 #include "vxfs_extern.h"
48 #include "vxfs_dir.h"
49 #include "vxfs_inode.h"
50
51
52 MODULE_AUTHOR("Christoph Hellwig, Krzysztof Blaszkowski");
53 MODULE_DESCRIPTION("Veritas Filesystem (VxFS) driver");
54 MODULE_LICENSE("Dual BSD/GPL");
55
56 static struct kmem_cache *vxfs_inode_cachep;
57
58 /**
59 * vxfs_put_super - free superblock resources
60 * @sbp: VFS superblock.
61 *
62 * Description:
63 * vxfs_put_super frees all resources allocated for @sbp
64 * after the last instance of the filesystem is unmounted.
65 */
66
67 static void
vxfs_put_super(struct super_block * sbp)68 vxfs_put_super(struct super_block *sbp)
69 {
70 struct vxfs_sb_info *infp = VXFS_SBI(sbp);
71
72 iput(infp->vsi_fship);
73 iput(infp->vsi_ilist);
74 iput(infp->vsi_stilist);
75
76 brelse(infp->vsi_bp);
77 kfree(infp);
78 }
79
80 /**
81 * vxfs_statfs - get filesystem information
82 * @dentry: VFS dentry to locate superblock
83 * @bufp: output buffer
84 *
85 * Description:
86 * vxfs_statfs fills the statfs buffer @bufp with information
87 * about the filesystem described by @dentry.
88 *
89 * Returns:
90 * Zero.
91 *
92 * Locking:
93 * No locks held.
94 *
95 * Notes:
96 * This is everything but complete...
97 */
98 static int
vxfs_statfs(struct dentry * dentry,struct kstatfs * bufp)99 vxfs_statfs(struct dentry *dentry, struct kstatfs *bufp)
100 {
101 struct vxfs_sb_info *infp = VXFS_SBI(dentry->d_sb);
102 struct vxfs_sb *raw_sb = infp->vsi_raw;
103
104 bufp->f_type = VXFS_SUPER_MAGIC;
105 bufp->f_bsize = dentry->d_sb->s_blocksize;
106 bufp->f_blocks = fs32_to_cpu(infp, raw_sb->vs_dsize);
107 bufp->f_bfree = fs32_to_cpu(infp, raw_sb->vs_free);
108 bufp->f_bavail = 0;
109 bufp->f_files = 0;
110 bufp->f_ffree = fs32_to_cpu(infp, raw_sb->vs_ifree);
111 bufp->f_namelen = VXFS_NAMELEN;
112
113 return 0;
114 }
115
vxfs_remount(struct super_block * sb,int * flags,char * data)116 static int vxfs_remount(struct super_block *sb, int *flags, char *data)
117 {
118 sync_filesystem(sb);
119 *flags |= SB_RDONLY;
120 return 0;
121 }
122
vxfs_alloc_inode(struct super_block * sb)123 static struct inode *vxfs_alloc_inode(struct super_block *sb)
124 {
125 struct vxfs_inode_info *vi;
126
127 vi = kmem_cache_alloc(vxfs_inode_cachep, GFP_KERNEL);
128 if (!vi)
129 return NULL;
130 inode_init_once(&vi->vfs_inode);
131 return &vi->vfs_inode;
132 }
133
vxfs_free_inode(struct inode * inode)134 static void vxfs_free_inode(struct inode *inode)
135 {
136 kmem_cache_free(vxfs_inode_cachep, VXFS_INO(inode));
137 }
138
139 static const struct super_operations vxfs_super_ops = {
140 .alloc_inode = vxfs_alloc_inode,
141 .free_inode = vxfs_free_inode,
142 .evict_inode = vxfs_evict_inode,
143 .put_super = vxfs_put_super,
144 .statfs = vxfs_statfs,
145 .remount_fs = vxfs_remount,
146 };
147
vxfs_try_sb_magic(struct super_block * sbp,int silent,unsigned blk,__fs32 magic)148 static int vxfs_try_sb_magic(struct super_block *sbp, int silent,
149 unsigned blk, __fs32 magic)
150 {
151 struct buffer_head *bp;
152 struct vxfs_sb *rsbp;
153 struct vxfs_sb_info *infp = VXFS_SBI(sbp);
154 int rc = -ENOMEM;
155
156 bp = sb_bread(sbp, blk);
157 do {
158 if (!bp || !buffer_mapped(bp)) {
159 if (!silent) {
160 printk(KERN_WARNING
161 "vxfs: unable to read disk superblock at %u\n",
162 blk);
163 }
164 break;
165 }
166
167 rc = -EINVAL;
168 rsbp = (struct vxfs_sb *)bp->b_data;
169 if (rsbp->vs_magic != magic) {
170 if (!silent)
171 printk(KERN_NOTICE
172 "vxfs: WRONG superblock magic %08x at %u\n",
173 rsbp->vs_magic, blk);
174 break;
175 }
176
177 rc = 0;
178 infp->vsi_raw = rsbp;
179 infp->vsi_bp = bp;
180 } while (0);
181
182 if (rc) {
183 infp->vsi_raw = NULL;
184 infp->vsi_bp = NULL;
185 brelse(bp);
186 }
187
188 return rc;
189 }
190
191 /**
192 * vxfs_read_super - read superblock into memory and initialize filesystem
193 * @sbp: VFS superblock (to fill)
194 * @dp: fs private mount data
195 * @silent: do not complain loudly when sth is wrong
196 *
197 * Description:
198 * We are called on the first mount of a filesystem to read the
199 * superblock into memory and do some basic setup.
200 *
201 * Returns:
202 * The superblock on success, else %NULL.
203 *
204 * Locking:
205 * We are under @sbp->s_lock.
206 */
vxfs_fill_super(struct super_block * sbp,void * dp,int silent)207 static int vxfs_fill_super(struct super_block *sbp, void *dp, int silent)
208 {
209 struct vxfs_sb_info *infp;
210 struct vxfs_sb *rsbp;
211 u_long bsize;
212 struct inode *root;
213 int ret = -EINVAL;
214 u32 j;
215
216 sbp->s_flags |= SB_RDONLY;
217
218 infp = kzalloc(sizeof(*infp), GFP_KERNEL);
219 if (!infp) {
220 printk(KERN_WARNING "vxfs: unable to allocate incore superblock\n");
221 return -ENOMEM;
222 }
223
224 bsize = sb_min_blocksize(sbp, BLOCK_SIZE);
225 if (!bsize) {
226 printk(KERN_WARNING "vxfs: unable to set blocksize\n");
227 goto out;
228 }
229
230 sbp->s_op = &vxfs_super_ops;
231 sbp->s_fs_info = infp;
232 sbp->s_time_min = 0;
233 sbp->s_time_max = U32_MAX;
234
235 if (!vxfs_try_sb_magic(sbp, silent, 1,
236 (__force __fs32)cpu_to_le32(VXFS_SUPER_MAGIC))) {
237 /* Unixware, x86 */
238 infp->byte_order = VXFS_BO_LE;
239 } else if (!vxfs_try_sb_magic(sbp, silent, 8,
240 (__force __fs32)cpu_to_be32(VXFS_SUPER_MAGIC))) {
241 /* HP-UX, parisc */
242 infp->byte_order = VXFS_BO_BE;
243 } else {
244 if (!silent)
245 printk(KERN_NOTICE "vxfs: can't find superblock.\n");
246 goto out;
247 }
248
249 rsbp = infp->vsi_raw;
250 j = fs32_to_cpu(infp, rsbp->vs_version);
251 if ((j < 2 || j > 4) && !silent) {
252 printk(KERN_NOTICE "vxfs: unsupported VxFS version (%d)\n", j);
253 goto out;
254 }
255
256 #ifdef DIAGNOSTIC
257 printk(KERN_DEBUG "vxfs: supported VxFS version (%d)\n", j);
258 printk(KERN_DEBUG "vxfs: blocksize: %d\n",
259 fs32_to_cpu(infp, rsbp->vs_bsize));
260 #endif
261
262 sbp->s_magic = fs32_to_cpu(infp, rsbp->vs_magic);
263
264 infp->vsi_oltext = fs32_to_cpu(infp, rsbp->vs_oltext[0]);
265 infp->vsi_oltsize = fs32_to_cpu(infp, rsbp->vs_oltsize);
266
267 j = fs32_to_cpu(infp, rsbp->vs_bsize);
268 if (!sb_set_blocksize(sbp, j)) {
269 printk(KERN_WARNING "vxfs: unable to set final block size\n");
270 goto out;
271 }
272
273 if (vxfs_read_olt(sbp, bsize)) {
274 printk(KERN_WARNING "vxfs: unable to read olt\n");
275 goto out;
276 }
277
278 if (vxfs_read_fshead(sbp)) {
279 printk(KERN_WARNING "vxfs: unable to read fshead\n");
280 goto out;
281 }
282
283 root = vxfs_iget(sbp, VXFS_ROOT_INO);
284 if (IS_ERR(root)) {
285 ret = PTR_ERR(root);
286 goto out;
287 }
288 sbp->s_root = d_make_root(root);
289 if (!sbp->s_root) {
290 printk(KERN_WARNING "vxfs: unable to get root dentry.\n");
291 goto out_free_ilist;
292 }
293
294 return 0;
295
296 out_free_ilist:
297 iput(infp->vsi_fship);
298 iput(infp->vsi_ilist);
299 iput(infp->vsi_stilist);
300 out:
301 brelse(infp->vsi_bp);
302 kfree(infp);
303 return ret;
304 }
305
306 /*
307 * The usual module blurb.
308 */
vxfs_mount(struct file_system_type * fs_type,int flags,const char * dev_name,void * data)309 static struct dentry *vxfs_mount(struct file_system_type *fs_type,
310 int flags, const char *dev_name, void *data)
311 {
312 return mount_bdev(fs_type, flags, dev_name, data, vxfs_fill_super);
313 }
314
315 static struct file_system_type vxfs_fs_type = {
316 .owner = THIS_MODULE,
317 .name = "vxfs",
318 .mount = vxfs_mount,
319 .kill_sb = kill_block_super,
320 .fs_flags = FS_REQUIRES_DEV,
321 };
322 MODULE_ALIAS_FS("vxfs"); /* makes mount -t vxfs autoload the module */
323 MODULE_ALIAS("vxfs");
324
325 static int __init
vxfs_init(void)326 vxfs_init(void)
327 {
328 int rv;
329
330 vxfs_inode_cachep = kmem_cache_create_usercopy("vxfs_inode",
331 sizeof(struct vxfs_inode_info), 0,
332 SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD,
333 offsetof(struct vxfs_inode_info, vii_immed.vi_immed),
334 sizeof_field(struct vxfs_inode_info,
335 vii_immed.vi_immed),
336 NULL);
337 if (!vxfs_inode_cachep)
338 return -ENOMEM;
339 rv = register_filesystem(&vxfs_fs_type);
340 if (rv < 0)
341 kmem_cache_destroy(vxfs_inode_cachep);
342 return rv;
343 }
344
345 static void __exit
vxfs_cleanup(void)346 vxfs_cleanup(void)
347 {
348 unregister_filesystem(&vxfs_fs_type);
349 /*
350 * Make sure all delayed rcu free inodes are flushed before we
351 * destroy cache.
352 */
353 rcu_barrier();
354 kmem_cache_destroy(vxfs_inode_cachep);
355 }
356
357 module_init(vxfs_init);
358 module_exit(vxfs_cleanup);
359