1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2000-2001 Christoph Hellwig.
4 * Copyright (c) 2016 Krzysztof Blaszkowski
5 */
6
7/*
8 * Veritas filesystem driver - superblock related routines.
9 */
10#include <linux/init.h>
11#include <linux/module.h>
12
13#include <linux/blkdev.h>
14#include <linux/fs.h>
15#include <linux/buffer_head.h>
16#include <linux/kernel.h>
17#include <linux/slab.h>
18#include <linux/stat.h>
19#include <linux/vfs.h>
20#include <linux/mount.h>
21
22#include "vxfs.h"
23#include "vxfs_extern.h"
24#include "vxfs_dir.h"
25#include "vxfs_inode.h"
26
27
28MODULE_AUTHOR("Christoph Hellwig, Krzysztof Blaszkowski");
29MODULE_DESCRIPTION("Veritas Filesystem (VxFS) driver");
30MODULE_LICENSE("Dual BSD/GPL");
31
32static struct kmem_cache *vxfs_inode_cachep;
33
34/**
35 * vxfs_put_super - free superblock resources
36 * @sbp: VFS superblock.
37 *
38 * Description:
39 * vxfs_put_super frees all resources allocated for @sbp
40 * after the last instance of the filesystem is unmounted.
41 */
42
43static void
44vxfs_put_super(struct super_block *sbp)
45{
46 struct vxfs_sb_info *infp = VXFS_SBI(sbp);
47
48 iput(infp->vsi_fship);
49 iput(infp->vsi_ilist);
50 iput(infp->vsi_stilist);
51
52 brelse(bh: infp->vsi_bp);
53 kfree(objp: infp);
54}
55
56/**
57 * vxfs_statfs - get filesystem information
58 * @dentry: VFS dentry to locate superblock
59 * @bufp: output buffer
60 *
61 * Description:
62 * vxfs_statfs fills the statfs buffer @bufp with information
63 * about the filesystem described by @dentry.
64 *
65 * Returns:
66 * Zero.
67 *
68 * Locking:
69 * No locks held.
70 *
71 * Notes:
72 * This is everything but complete...
73 */
74static int
75vxfs_statfs(struct dentry *dentry, struct kstatfs *bufp)
76{
77 struct vxfs_sb_info *infp = VXFS_SBI(dentry->d_sb);
78 struct vxfs_sb *raw_sb = infp->vsi_raw;
79 u64 id = huge_encode_dev(dev: dentry->d_sb->s_bdev->bd_dev);
80
81 bufp->f_type = VXFS_SUPER_MAGIC;
82 bufp->f_bsize = dentry->d_sb->s_blocksize;
83 bufp->f_blocks = fs32_to_cpu(sbi: infp, a: raw_sb->vs_dsize);
84 bufp->f_bfree = fs32_to_cpu(sbi: infp, a: raw_sb->vs_free);
85 bufp->f_bavail = 0;
86 bufp->f_files = 0;
87 bufp->f_ffree = fs32_to_cpu(sbi: infp, a: raw_sb->vs_ifree);
88 bufp->f_fsid = u64_to_fsid(v: id);
89 bufp->f_namelen = VXFS_NAMELEN;
90
91 return 0;
92}
93
94static int vxfs_remount(struct super_block *sb, int *flags, char *data)
95{
96 sync_filesystem(sb);
97 *flags |= SB_RDONLY;
98 return 0;
99}
100
101static struct inode *vxfs_alloc_inode(struct super_block *sb)
102{
103 struct vxfs_inode_info *vi;
104
105 vi = alloc_inode_sb(sb, cache: vxfs_inode_cachep, GFP_KERNEL);
106 if (!vi)
107 return NULL;
108 inode_init_once(&vi->vfs_inode);
109 return &vi->vfs_inode;
110}
111
112static void vxfs_free_inode(struct inode *inode)
113{
114 kmem_cache_free(s: vxfs_inode_cachep, objp: VXFS_INO(inode));
115}
116
117static const struct super_operations vxfs_super_ops = {
118 .alloc_inode = vxfs_alloc_inode,
119 .free_inode = vxfs_free_inode,
120 .evict_inode = vxfs_evict_inode,
121 .put_super = vxfs_put_super,
122 .statfs = vxfs_statfs,
123 .remount_fs = vxfs_remount,
124};
125
126static int vxfs_try_sb_magic(struct super_block *sbp, int silent,
127 unsigned blk, __fs32 magic)
128{
129 struct buffer_head *bp;
130 struct vxfs_sb *rsbp;
131 struct vxfs_sb_info *infp = VXFS_SBI(sbp);
132 int rc = -ENOMEM;
133
134 bp = sb_bread(sb: sbp, block: blk);
135 do {
136 if (!bp || !buffer_mapped(bh: bp)) {
137 if (!silent) {
138 printk(KERN_WARNING
139 "vxfs: unable to read disk superblock at %u\n",
140 blk);
141 }
142 break;
143 }
144
145 rc = -EINVAL;
146 rsbp = (struct vxfs_sb *)bp->b_data;
147 if (rsbp->vs_magic != magic) {
148 if (!silent)
149 printk(KERN_NOTICE
150 "vxfs: WRONG superblock magic %08x at %u\n",
151 rsbp->vs_magic, blk);
152 break;
153 }
154
155 rc = 0;
156 infp->vsi_raw = rsbp;
157 infp->vsi_bp = bp;
158 } while (0);
159
160 if (rc) {
161 infp->vsi_raw = NULL;
162 infp->vsi_bp = NULL;
163 brelse(bh: bp);
164 }
165
166 return rc;
167}
168
169/**
170 * vxfs_fill_super - read superblock into memory and initialize filesystem
171 * @sbp: VFS superblock (to fill)
172 * @dp: fs private mount data
173 * @silent: do not complain loudly when sth is wrong
174 *
175 * Description:
176 * We are called on the first mount of a filesystem to read the
177 * superblock into memory and do some basic setup.
178 *
179 * Returns:
180 * The superblock on success, else %NULL.
181 *
182 * Locking:
183 * We are under @sbp->s_lock.
184 */
185static int vxfs_fill_super(struct super_block *sbp, void *dp, int silent)
186{
187 struct vxfs_sb_info *infp;
188 struct vxfs_sb *rsbp;
189 u_long bsize;
190 struct inode *root;
191 int ret = -EINVAL;
192 u32 j;
193
194 sbp->s_flags |= SB_RDONLY;
195
196 infp = kzalloc(size: sizeof(*infp), GFP_KERNEL);
197 if (!infp) {
198 printk(KERN_WARNING "vxfs: unable to allocate incore superblock\n");
199 return -ENOMEM;
200 }
201
202 bsize = sb_min_blocksize(sbp, BLOCK_SIZE);
203 if (!bsize) {
204 printk(KERN_WARNING "vxfs: unable to set blocksize\n");
205 goto out;
206 }
207
208 sbp->s_op = &vxfs_super_ops;
209 sbp->s_fs_info = infp;
210 sbp->s_time_min = 0;
211 sbp->s_time_max = U32_MAX;
212
213 if (!vxfs_try_sb_magic(sbp, silent, blk: 1,
214 magic: (__force __fs32)cpu_to_le32(VXFS_SUPER_MAGIC))) {
215 /* Unixware, x86 */
216 infp->byte_order = VXFS_BO_LE;
217 } else if (!vxfs_try_sb_magic(sbp, silent, blk: 8,
218 magic: (__force __fs32)cpu_to_be32(VXFS_SUPER_MAGIC))) {
219 /* HP-UX, parisc */
220 infp->byte_order = VXFS_BO_BE;
221 } else {
222 if (!silent)
223 printk(KERN_NOTICE "vxfs: can't find superblock.\n");
224 goto out;
225 }
226
227 rsbp = infp->vsi_raw;
228 j = fs32_to_cpu(sbi: infp, a: rsbp->vs_version);
229 if ((j < 2 || j > 4) && !silent) {
230 printk(KERN_NOTICE "vxfs: unsupported VxFS version (%d)\n", j);
231 goto out;
232 }
233
234#ifdef DIAGNOSTIC
235 printk(KERN_DEBUG "vxfs: supported VxFS version (%d)\n", j);
236 printk(KERN_DEBUG "vxfs: blocksize: %d\n",
237 fs32_to_cpu(infp, rsbp->vs_bsize));
238#endif
239
240 sbp->s_magic = fs32_to_cpu(sbi: infp, a: rsbp->vs_magic);
241
242 infp->vsi_oltext = fs32_to_cpu(sbi: infp, a: rsbp->vs_oltext[0]);
243 infp->vsi_oltsize = fs32_to_cpu(sbi: infp, a: rsbp->vs_oltsize);
244
245 j = fs32_to_cpu(sbi: infp, a: rsbp->vs_bsize);
246 if (!sb_set_blocksize(sbp, j)) {
247 printk(KERN_WARNING "vxfs: unable to set final block size\n");
248 goto out;
249 }
250
251 if (vxfs_read_olt(sbp, bsize)) {
252 printk(KERN_WARNING "vxfs: unable to read olt\n");
253 goto out;
254 }
255
256 if (vxfs_read_fshead(sbp)) {
257 printk(KERN_WARNING "vxfs: unable to read fshead\n");
258 goto out;
259 }
260
261 root = vxfs_iget(sbp, VXFS_ROOT_INO);
262 if (IS_ERR(ptr: root)) {
263 ret = PTR_ERR(ptr: root);
264 goto out;
265 }
266 sbp->s_root = d_make_root(root);
267 if (!sbp->s_root) {
268 printk(KERN_WARNING "vxfs: unable to get root dentry.\n");
269 goto out_free_ilist;
270 }
271
272 return 0;
273
274out_free_ilist:
275 iput(infp->vsi_fship);
276 iput(infp->vsi_ilist);
277 iput(infp->vsi_stilist);
278out:
279 brelse(bh: infp->vsi_bp);
280 kfree(objp: infp);
281 return ret;
282}
283
284/*
285 * The usual module blurb.
286 */
287static struct dentry *vxfs_mount(struct file_system_type *fs_type,
288 int flags, const char *dev_name, void *data)
289{
290 return mount_bdev(fs_type, flags, dev_name, data, fill_super: vxfs_fill_super);
291}
292
293static struct file_system_type vxfs_fs_type = {
294 .owner = THIS_MODULE,
295 .name = "vxfs",
296 .mount = vxfs_mount,
297 .kill_sb = kill_block_super,
298 .fs_flags = FS_REQUIRES_DEV,
299};
300MODULE_ALIAS_FS("vxfs"); /* makes mount -t vxfs autoload the module */
301MODULE_ALIAS("vxfs");
302
303static int __init
304vxfs_init(void)
305{
306 int rv;
307
308 vxfs_inode_cachep = kmem_cache_create_usercopy(name: "vxfs_inode",
309 size: sizeof(struct vxfs_inode_info), align: 0,
310 SLAB_RECLAIM_ACCOUNT|SLAB_MEM_SPREAD,
311 offsetof(struct vxfs_inode_info, vii_immed.vi_immed),
312 sizeof_field(struct vxfs_inode_info,
313 vii_immed.vi_immed),
314 NULL);
315 if (!vxfs_inode_cachep)
316 return -ENOMEM;
317 rv = register_filesystem(&vxfs_fs_type);
318 if (rv < 0)
319 kmem_cache_destroy(s: vxfs_inode_cachep);
320 return rv;
321}
322
323static void __exit
324vxfs_cleanup(void)
325{
326 unregister_filesystem(&vxfs_fs_type);
327 /*
328 * Make sure all delayed rcu free inodes are flushed before we
329 * destroy cache.
330 */
331 rcu_barrier();
332 kmem_cache_destroy(s: vxfs_inode_cachep);
333}
334
335module_init(vxfs_init);
336module_exit(vxfs_cleanup);
337

source code of linux/fs/freevxfs/vxfs_super.c