2 * linux/fs/adfs/super.c
4 * Copyright (C) 1997-1999 Russell King
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
10 #include <linux/module.h>
11 #include <linux/errno.h>
13 #include <linux/adfs_fs.h>
14 #include <linux/slab.h>
15 #include <linux/time.h>
16 #include <linux/stat.h>
17 #include <linux/string.h>
18 #include <linux/init.h>
19 #include <linux/buffer_head.h>
20 #include <linux/vfs.h>
21 #include <linux/parser.h>
22 #include <linux/bitops.h>
23 #include <linux/mount.h>
24 #include <linux/seq_file.h>
26 #include <asm/uaccess.h>
27 #include <asm/system.h>
33 #include "dir_fplus.h"
35 #define ADFS_DEFAULT_OWNER_MASK S_IRWXU
36 #define ADFS_DEFAULT_OTHER_MASK (S_IRWXG | S_IRWXO)
38 void __adfs_error(struct super_block *sb, const char *function, const char *fmt, ...)
44 vsnprintf(error_buf, sizeof(error_buf), fmt, args);
47 printk(KERN_CRIT "ADFS-fs error (device %s)%s%s: %s\n",
48 sb->s_id, function ? ": " : "",
49 function ? function : "", error_buf);
52 static int adfs_checkdiscrecord(struct adfs_discrecord *dr)
56 /* sector size must be 256, 512 or 1024 bytes */
57 if (dr->log2secsize != 8 &&
58 dr->log2secsize != 9 &&
59 dr->log2secsize != 10)
62 /* idlen must be at least log2secsize + 3 */
63 if (dr->idlen < dr->log2secsize + 3)
66 /* we cannot have such a large disc that we
67 * are unable to represent sector offsets in
68 * 32 bits. This works out at 2.0 TB.
70 if (le32_to_cpu(dr->disc_size_high) >> dr->log2secsize)
73 /* idlen must be no greater than 19 v2 [1.0] */
77 /* reserved bytes should be zero */
78 for (i = 0; i < sizeof(dr->unused52); i++)
79 if (dr->unused52[i] != 0)
85 static unsigned char adfs_calczonecheck(struct super_block *sb, unsigned char *map)
87 unsigned int v0, v1, v2, v3;
90 v0 = v1 = v2 = v3 = 0;
91 for (i = sb->s_blocksize - 4; i; i -= 4) {
92 v0 += map[i] + (v3 >> 8);
94 v1 += map[i + 1] + (v0 >> 8);
96 v2 += map[i + 2] + (v1 >> 8);
98 v3 += map[i + 3] + (v2 >> 8);
102 v1 += map[1] + (v0 >> 8);
103 v2 += map[2] + (v1 >> 8);
104 v3 += map[3] + (v2 >> 8);
106 return v0 ^ v1 ^ v2 ^ v3;
109 static int adfs_checkmap(struct super_block *sb, struct adfs_discmap *dm)
111 unsigned char crosscheck = 0, zonecheck = 1;
114 for (i = 0; i < ADFS_SB(sb)->s_map_size; i++) {
117 map = dm[i].dm_bh->b_data;
119 if (adfs_calczonecheck(sb, map) != map[0]) {
120 adfs_error(sb, "zone %d fails zonecheck", i);
123 crosscheck ^= map[3];
125 if (crosscheck != 0xff)
126 adfs_error(sb, "crosscheck != 0xff");
127 return crosscheck == 0xff && zonecheck;
130 static void adfs_put_super(struct super_block *sb)
133 struct adfs_sb_info *asb = ADFS_SB(sb);
135 for (i = 0; i < asb->s_map_size; i++)
136 brelse(asb->s_map[i].dm_bh);
139 sb->s_fs_info = NULL;
142 static int adfs_show_options(struct seq_file *seq, struct vfsmount *mnt)
144 struct adfs_sb_info *asb = ADFS_SB(mnt->mnt_sb);
147 seq_printf(seq, ",uid=%u", asb->s_uid);
149 seq_printf(seq, ",gid=%u", asb->s_gid);
150 if (asb->s_owner_mask != ADFS_DEFAULT_OWNER_MASK)
151 seq_printf(seq, ",ownmask=%o", asb->s_owner_mask);
152 if (asb->s_other_mask != ADFS_DEFAULT_OTHER_MASK)
153 seq_printf(seq, ",othmask=%o", asb->s_other_mask);
158 enum {Opt_uid, Opt_gid, Opt_ownmask, Opt_othmask, Opt_err};
160 static const match_table_t tokens = {
163 {Opt_ownmask, "ownmask=%o"},
164 {Opt_othmask, "othmask=%o"},
168 static int parse_options(struct super_block *sb, char *options)
171 struct adfs_sb_info *asb = ADFS_SB(sb);
177 while ((p = strsep(&options, ",")) != NULL) {
178 substring_t args[MAX_OPT_ARGS];
183 token = match_token(p, tokens, args);
186 if (match_int(args, &option))
191 if (match_int(args, &option))
196 if (match_octal(args, &option))
198 asb->s_owner_mask = option;
201 if (match_octal(args, &option))
203 asb->s_other_mask = option;
206 printk("ADFS-fs: unrecognised mount option \"%s\" "
207 "or missing value\n", p);
214 static int adfs_remount(struct super_block *sb, int *flags, char *data)
216 *flags |= MS_NODIRATIME;
217 return parse_options(sb, data);
220 static int adfs_statfs(struct dentry *dentry, struct kstatfs *buf)
222 struct adfs_sb_info *asb = ADFS_SB(dentry->d_sb);
224 buf->f_type = ADFS_SUPER_MAGIC;
225 buf->f_namelen = asb->s_namelen;
226 buf->f_bsize = dentry->d_sb->s_blocksize;
227 buf->f_blocks = asb->s_size;
228 buf->f_files = asb->s_ids_per_zone * asb->s_map_size;
230 buf->f_bfree = adfs_map_free(dentry->d_sb);
231 buf->f_ffree = (long)(buf->f_bfree * buf->f_files) / (long)buf->f_blocks;
236 static struct kmem_cache *adfs_inode_cachep;
238 static struct inode *adfs_alloc_inode(struct super_block *sb)
240 struct adfs_inode_info *ei;
241 ei = (struct adfs_inode_info *)kmem_cache_alloc(adfs_inode_cachep, GFP_KERNEL);
244 return &ei->vfs_inode;
247 static void adfs_destroy_inode(struct inode *inode)
249 kmem_cache_free(adfs_inode_cachep, ADFS_I(inode));
252 static void init_once(void *foo)
254 struct adfs_inode_info *ei = (struct adfs_inode_info *) foo;
256 inode_init_once(&ei->vfs_inode);
259 static int init_inodecache(void)
261 adfs_inode_cachep = kmem_cache_create("adfs_inode_cache",
262 sizeof(struct adfs_inode_info),
263 0, (SLAB_RECLAIM_ACCOUNT|
266 if (adfs_inode_cachep == NULL)
271 static void destroy_inodecache(void)
273 kmem_cache_destroy(adfs_inode_cachep);
276 static const struct super_operations adfs_sops = {
277 .alloc_inode = adfs_alloc_inode,
278 .destroy_inode = adfs_destroy_inode,
279 .write_inode = adfs_write_inode,
280 .put_super = adfs_put_super,
281 .statfs = adfs_statfs,
282 .remount_fs = adfs_remount,
283 .show_options = adfs_show_options,
286 static struct adfs_discmap *adfs_read_map(struct super_block *sb, struct adfs_discrecord *dr)
288 struct adfs_discmap *dm;
289 unsigned int map_addr, zone_size, nzones;
291 struct adfs_sb_info *asb = ADFS_SB(sb);
293 nzones = asb->s_map_size;
294 zone_size = (8 << dr->log2secsize) - le16_to_cpu(dr->zone_spare);
295 map_addr = (nzones >> 1) * zone_size -
296 ((nzones > 1) ? ADFS_DR_SIZE_BITS : 0);
297 map_addr = signed_asl(map_addr, asb->s_map2blk);
299 asb->s_ids_per_zone = zone_size / (asb->s_idlen + 1);
301 dm = kmalloc(nzones * sizeof(*dm), GFP_KERNEL);
303 adfs_error(sb, "not enough memory");
307 for (zone = 0; zone < nzones; zone++, map_addr++) {
308 dm[zone].dm_startbit = 0;
309 dm[zone].dm_endbit = zone_size;
310 dm[zone].dm_startblk = zone * zone_size - ADFS_DR_SIZE_BITS;
311 dm[zone].dm_bh = sb_bread(sb, map_addr);
313 if (!dm[zone].dm_bh) {
314 adfs_error(sb, "unable to read map");
319 /* adjust the limits for the first and last map zones */
321 dm[0].dm_startblk = 0;
322 dm[0].dm_startbit = ADFS_DR_SIZE_BITS;
323 dm[i].dm_endbit = (le32_to_cpu(dr->disc_size_high) << (32 - dr->log2bpmb)) +
324 (le32_to_cpu(dr->disc_size) >> dr->log2bpmb) +
325 (ADFS_DR_SIZE_BITS - i * zone_size);
327 if (adfs_checkmap(sb, dm))
330 adfs_error(sb, "map corrupted");
334 brelse(dm[zone].dm_bh);
340 static inline unsigned long adfs_discsize(struct adfs_discrecord *dr, int block_bits)
342 unsigned long discsize;
344 discsize = le32_to_cpu(dr->disc_size_high) << (32 - block_bits);
345 discsize |= le32_to_cpu(dr->disc_size) >> block_bits;
350 static int adfs_fill_super(struct super_block *sb, void *data, int silent)
352 struct adfs_discrecord *dr;
353 struct buffer_head *bh;
354 struct object_info root_obj;
355 unsigned char *b_data;
356 struct adfs_sb_info *asb;
359 sb->s_flags |= MS_NODIRATIME;
361 asb = kzalloc(sizeof(*asb), GFP_KERNEL);
366 /* set default options */
369 asb->s_owner_mask = ADFS_DEFAULT_OWNER_MASK;
370 asb->s_other_mask = ADFS_DEFAULT_OTHER_MASK;
372 if (parse_options(sb, data))
375 sb_set_blocksize(sb, BLOCK_SIZE);
376 if (!(bh = sb_bread(sb, ADFS_DISCRECORD / BLOCK_SIZE))) {
377 adfs_error(sb, "unable to read superblock");
381 b_data = bh->b_data + (ADFS_DISCRECORD % BLOCK_SIZE);
383 if (adfs_checkbblk(b_data)) {
385 printk("VFS: Can't find an adfs filesystem on dev "
390 dr = (struct adfs_discrecord *)(b_data + ADFS_DR_OFFSET);
393 * Do some sanity checks on the ADFS disc record
395 if (adfs_checkdiscrecord(dr)) {
397 printk("VPS: Can't find an adfs filesystem on dev "
403 if (sb_set_blocksize(sb, 1 << dr->log2secsize)) {
404 bh = sb_bread(sb, ADFS_DISCRECORD / sb->s_blocksize);
406 adfs_error(sb, "couldn't read superblock on "
410 b_data = bh->b_data + (ADFS_DISCRECORD % sb->s_blocksize);
411 if (adfs_checkbblk(b_data)) {
412 adfs_error(sb, "disc record mismatch, very weird!");
415 dr = (struct adfs_discrecord *)(b_data + ADFS_DR_OFFSET);
418 printk(KERN_ERR "VFS: Unsupported blocksize on dev "
424 * blocksize on this device should now be set to the ADFS log2secsize
427 sb->s_magic = ADFS_SUPER_MAGIC;
428 asb->s_idlen = dr->idlen;
429 asb->s_map_size = dr->nzones | (dr->nzones_high << 8);
430 asb->s_map2blk = dr->log2bpmb - dr->log2secsize;
431 asb->s_size = adfs_discsize(dr, sb->s_blocksize_bits);
432 asb->s_version = dr->format_version;
433 asb->s_log2sharesize = dr->log2sharesize;
435 asb->s_map = adfs_read_map(sb, dr);
442 * set up enough so that we can read an inode
444 sb->s_op = &adfs_sops;
446 dr = (struct adfs_discrecord *)(asb->s_map[0].dm_bh->b_data + 4);
448 root_obj.parent_id = root_obj.file_id = le32_to_cpu(dr->root);
449 root_obj.name_len = 0;
450 root_obj.loadaddr = 0;
451 root_obj.execaddr = 0;
452 root_obj.size = ADFS_NEWDIR_SIZE;
453 root_obj.attr = ADFS_NDA_DIRECTORY | ADFS_NDA_OWNER_READ |
454 ADFS_NDA_OWNER_WRITE | ADFS_NDA_PUBLIC_READ;
457 * If this is a F+ disk with variable length directories,
458 * get the root_size from the disc record.
460 if (asb->s_version) {
461 root_obj.size = le32_to_cpu(dr->root_size);
462 asb->s_dir = &adfs_fplus_dir_ops;
463 asb->s_namelen = ADFS_FPLUS_NAME_LEN;
465 asb->s_dir = &adfs_f_dir_ops;
466 asb->s_namelen = ADFS_F_NAME_LEN;
469 root = adfs_iget(sb, &root_obj);
470 sb->s_root = d_alloc_root(root);
474 for (i = 0; i < asb->s_map_size; i++)
475 brelse(asb->s_map[i].dm_bh);
477 adfs_error(sb, "get root inode failed\n");
480 sb->s_root->d_op = &adfs_dentry_operations;
486 sb->s_fs_info = NULL;
491 static int adfs_get_sb(struct file_system_type *fs_type,
492 int flags, const char *dev_name, void *data, struct vfsmount *mnt)
494 return get_sb_bdev(fs_type, flags, dev_name, data, adfs_fill_super,
498 static struct file_system_type adfs_fs_type = {
499 .owner = THIS_MODULE,
501 .get_sb = adfs_get_sb,
502 .kill_sb = kill_block_super,
503 .fs_flags = FS_REQUIRES_DEV,
506 static int __init init_adfs_fs(void)
508 int err = init_inodecache();
511 err = register_filesystem(&adfs_fs_type);
516 destroy_inodecache();
521 static void __exit exit_adfs_fs(void)
523 unregister_filesystem(&adfs_fs_type);
524 destroy_inodecache();
527 module_init(init_adfs_fs)
528 module_exit(exit_adfs_fs)