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 | |
28 | MODULE_AUTHOR("Christoph Hellwig, Krzysztof Blaszkowski" ); |
29 | MODULE_DESCRIPTION("Veritas Filesystem (VxFS) driver" ); |
30 | MODULE_LICENSE("Dual BSD/GPL" ); |
31 | |
32 | static 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 | |
43 | static void |
44 | vxfs_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 | */ |
74 | static int |
75 | vxfs_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 | |
94 | static 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 | |
101 | static 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 | |
112 | static void vxfs_free_inode(struct inode *inode) |
113 | { |
114 | kmem_cache_free(s: vxfs_inode_cachep, objp: VXFS_INO(inode)); |
115 | } |
116 | |
117 | static 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 | |
126 | static 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 | */ |
185 | static 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 | |
274 | out_free_ilist: |
275 | iput(infp->vsi_fship); |
276 | iput(infp->vsi_ilist); |
277 | iput(infp->vsi_stilist); |
278 | out: |
279 | brelse(bh: infp->vsi_bp); |
280 | kfree(objp: infp); |
281 | return ret; |
282 | } |
283 | |
284 | /* |
285 | * The usual module blurb. |
286 | */ |
287 | static 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 | |
293 | static 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 | }; |
300 | MODULE_ALIAS_FS("vxfs" ); /* makes mount -t vxfs autoload the module */ |
301 | MODULE_ALIAS("vxfs" ); |
302 | |
303 | static int __init |
304 | vxfs_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 | |
323 | static void __exit |
324 | vxfs_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 | |
335 | module_init(vxfs_init); |
336 | module_exit(vxfs_cleanup); |
337 | |