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/init.h>
12 #include <linux/buffer_head.h>
13 #include <linux/parser.h>
14 #include <linux/mount.h>
15 #include <linux/seq_file.h>
16 #include <linux/slab.h>
17 #include <linux/smp_lock.h>
18 #include <linux/statfs.h>
21 #include "dir_fplus.h"
23 #define ADFS_DEFAULT_OWNER_MASK S_IRWXU
24 #define ADFS_DEFAULT_OTHER_MASK (S_IRWXG | S_IRWXO)
26 void __adfs_error(struct super_block *sb, const char *function, const char *fmt, ...)
32 vsnprintf(error_buf, sizeof(error_buf), fmt, args);
35 printk(KERN_CRIT "ADFS-fs error (device %s)%s%s: %s\n",
36 sb->s_id, function ? ": " : "",
37 function ? function : "", error_buf);
40 static int adfs_checkdiscrecord(struct adfs_discrecord *dr)
44 /* sector size must be 256, 512 or 1024 bytes */
45 if (dr->log2secsize != 8 &&
46 dr->log2secsize != 9 &&
47 dr->log2secsize != 10)
50 /* idlen must be at least log2secsize + 3 */
51 if (dr->idlen < dr->log2secsize + 3)
54 /* we cannot have such a large disc that we
55 * are unable to represent sector offsets in
56 * 32 bits. This works out at 2.0 TB.
58 if (le32_to_cpu(dr->disc_size_high) >> dr->log2secsize)
61 /* idlen must be no greater than 19 v2 [1.0] */
65 /* reserved bytes should be zero */
66 for (i = 0; i < sizeof(dr->unused52); i++)
67 if (dr->unused52[i] != 0)
73 static unsigned char adfs_calczonecheck(struct super_block *sb, unsigned char *map)
75 unsigned int v0, v1, v2, v3;
78 v0 = v1 = v2 = v3 = 0;
79 for (i = sb->s_blocksize - 4; i; i -= 4) {
80 v0 += map[i] + (v3 >> 8);
82 v1 += map[i + 1] + (v0 >> 8);
84 v2 += map[i + 2] + (v1 >> 8);
86 v3 += map[i + 3] + (v2 >> 8);
90 v1 += map[1] + (v0 >> 8);
91 v2 += map[2] + (v1 >> 8);
92 v3 += map[3] + (v2 >> 8);
94 return v0 ^ v1 ^ v2 ^ v3;
97 static int adfs_checkmap(struct super_block *sb, struct adfs_discmap *dm)
99 unsigned char crosscheck = 0, zonecheck = 1;
102 for (i = 0; i < ADFS_SB(sb)->s_map_size; i++) {
105 map = dm[i].dm_bh->b_data;
107 if (adfs_calczonecheck(sb, map) != map[0]) {
108 adfs_error(sb, "zone %d fails zonecheck", i);
111 crosscheck ^= map[3];
113 if (crosscheck != 0xff)
114 adfs_error(sb, "crosscheck != 0xff");
115 return crosscheck == 0xff && zonecheck;
118 static void adfs_put_super(struct super_block *sb)
121 struct adfs_sb_info *asb = ADFS_SB(sb);
125 for (i = 0; i < asb->s_map_size; i++)
126 brelse(asb->s_map[i].dm_bh);
129 sb->s_fs_info = NULL;
134 static int adfs_show_options(struct seq_file *seq, struct vfsmount *mnt)
136 struct adfs_sb_info *asb = ADFS_SB(mnt->mnt_sb);
139 seq_printf(seq, ",uid=%u", asb->s_uid);
141 seq_printf(seq, ",gid=%u", asb->s_gid);
142 if (asb->s_owner_mask != ADFS_DEFAULT_OWNER_MASK)
143 seq_printf(seq, ",ownmask=%o", asb->s_owner_mask);
144 if (asb->s_other_mask != ADFS_DEFAULT_OTHER_MASK)
145 seq_printf(seq, ",othmask=%o", asb->s_other_mask);
150 enum {Opt_uid, Opt_gid, Opt_ownmask, Opt_othmask, Opt_err};
152 static const match_table_t tokens = {
155 {Opt_ownmask, "ownmask=%o"},
156 {Opt_othmask, "othmask=%o"},
160 static int parse_options(struct super_block *sb, char *options)
163 struct adfs_sb_info *asb = ADFS_SB(sb);
169 while ((p = strsep(&options, ",")) != NULL) {
170 substring_t args[MAX_OPT_ARGS];
175 token = match_token(p, tokens, args);
178 if (match_int(args, &option))
183 if (match_int(args, &option))
188 if (match_octal(args, &option))
190 asb->s_owner_mask = option;
193 if (match_octal(args, &option))
195 asb->s_other_mask = option;
198 printk("ADFS-fs: unrecognised mount option \"%s\" "
199 "or missing value\n", p);
206 static int adfs_remount(struct super_block *sb, int *flags, char *data)
208 *flags |= MS_NODIRATIME;
209 return parse_options(sb, data);
212 static int adfs_statfs(struct dentry *dentry, struct kstatfs *buf)
214 struct super_block *sb = dentry->d_sb;
215 struct adfs_sb_info *sbi = ADFS_SB(sb);
216 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
218 buf->f_type = ADFS_SUPER_MAGIC;
219 buf->f_namelen = sbi->s_namelen;
220 buf->f_bsize = sb->s_blocksize;
221 buf->f_blocks = sbi->s_size;
222 buf->f_files = sbi->s_ids_per_zone * sbi->s_map_size;
224 buf->f_bfree = adfs_map_free(sb);
225 buf->f_ffree = (long)(buf->f_bfree * buf->f_files) / (long)buf->f_blocks;
226 buf->f_fsid.val[0] = (u32)id;
227 buf->f_fsid.val[1] = (u32)(id >> 32);
232 static struct kmem_cache *adfs_inode_cachep;
234 static struct inode *adfs_alloc_inode(struct super_block *sb)
236 struct adfs_inode_info *ei;
237 ei = (struct adfs_inode_info *)kmem_cache_alloc(adfs_inode_cachep, GFP_KERNEL);
240 return &ei->vfs_inode;
243 static void adfs_destroy_inode(struct inode *inode)
245 kmem_cache_free(adfs_inode_cachep, ADFS_I(inode));
248 static void init_once(void *foo)
250 struct adfs_inode_info *ei = (struct adfs_inode_info *) foo;
252 inode_init_once(&ei->vfs_inode);
255 static int init_inodecache(void)
257 adfs_inode_cachep = kmem_cache_create("adfs_inode_cache",
258 sizeof(struct adfs_inode_info),
259 0, (SLAB_RECLAIM_ACCOUNT|
262 if (adfs_inode_cachep == NULL)
267 static void destroy_inodecache(void)
269 kmem_cache_destroy(adfs_inode_cachep);
272 static const struct super_operations adfs_sops = {
273 .alloc_inode = adfs_alloc_inode,
274 .destroy_inode = adfs_destroy_inode,
275 .write_inode = adfs_write_inode,
276 .put_super = adfs_put_super,
277 .statfs = adfs_statfs,
278 .remount_fs = adfs_remount,
279 .show_options = adfs_show_options,
282 static struct adfs_discmap *adfs_read_map(struct super_block *sb, struct adfs_discrecord *dr)
284 struct adfs_discmap *dm;
285 unsigned int map_addr, zone_size, nzones;
287 struct adfs_sb_info *asb = ADFS_SB(sb);
289 nzones = asb->s_map_size;
290 zone_size = (8 << dr->log2secsize) - le16_to_cpu(dr->zone_spare);
291 map_addr = (nzones >> 1) * zone_size -
292 ((nzones > 1) ? ADFS_DR_SIZE_BITS : 0);
293 map_addr = signed_asl(map_addr, asb->s_map2blk);
295 asb->s_ids_per_zone = zone_size / (asb->s_idlen + 1);
297 dm = kmalloc(nzones * sizeof(*dm), GFP_KERNEL);
299 adfs_error(sb, "not enough memory");
303 for (zone = 0; zone < nzones; zone++, map_addr++) {
304 dm[zone].dm_startbit = 0;
305 dm[zone].dm_endbit = zone_size;
306 dm[zone].dm_startblk = zone * zone_size - ADFS_DR_SIZE_BITS;
307 dm[zone].dm_bh = sb_bread(sb, map_addr);
309 if (!dm[zone].dm_bh) {
310 adfs_error(sb, "unable to read map");
315 /* adjust the limits for the first and last map zones */
317 dm[0].dm_startblk = 0;
318 dm[0].dm_startbit = ADFS_DR_SIZE_BITS;
319 dm[i].dm_endbit = (le32_to_cpu(dr->disc_size_high) << (32 - dr->log2bpmb)) +
320 (le32_to_cpu(dr->disc_size) >> dr->log2bpmb) +
321 (ADFS_DR_SIZE_BITS - i * zone_size);
323 if (adfs_checkmap(sb, dm))
326 adfs_error(sb, "map corrupted");
330 brelse(dm[zone].dm_bh);
336 static inline unsigned long adfs_discsize(struct adfs_discrecord *dr, int block_bits)
338 unsigned long discsize;
340 discsize = le32_to_cpu(dr->disc_size_high) << (32 - block_bits);
341 discsize |= le32_to_cpu(dr->disc_size) >> block_bits;
346 static int adfs_fill_super(struct super_block *sb, void *data, int silent)
348 struct adfs_discrecord *dr;
349 struct buffer_head *bh;
350 struct object_info root_obj;
351 unsigned char *b_data;
352 struct adfs_sb_info *asb;
355 sb->s_flags |= MS_NODIRATIME;
357 asb = kzalloc(sizeof(*asb), GFP_KERNEL);
362 /* set default options */
365 asb->s_owner_mask = ADFS_DEFAULT_OWNER_MASK;
366 asb->s_other_mask = ADFS_DEFAULT_OTHER_MASK;
368 if (parse_options(sb, data))
371 sb_set_blocksize(sb, BLOCK_SIZE);
372 if (!(bh = sb_bread(sb, ADFS_DISCRECORD / BLOCK_SIZE))) {
373 adfs_error(sb, "unable to read superblock");
377 b_data = bh->b_data + (ADFS_DISCRECORD % BLOCK_SIZE);
379 if (adfs_checkbblk(b_data)) {
381 printk("VFS: Can't find an adfs filesystem on dev "
386 dr = (struct adfs_discrecord *)(b_data + ADFS_DR_OFFSET);
389 * Do some sanity checks on the ADFS disc record
391 if (adfs_checkdiscrecord(dr)) {
393 printk("VPS: Can't find an adfs filesystem on dev "
399 if (sb_set_blocksize(sb, 1 << dr->log2secsize)) {
400 bh = sb_bread(sb, ADFS_DISCRECORD / sb->s_blocksize);
402 adfs_error(sb, "couldn't read superblock on "
406 b_data = bh->b_data + (ADFS_DISCRECORD % sb->s_blocksize);
407 if (adfs_checkbblk(b_data)) {
408 adfs_error(sb, "disc record mismatch, very weird!");
411 dr = (struct adfs_discrecord *)(b_data + ADFS_DR_OFFSET);
414 printk(KERN_ERR "VFS: Unsupported blocksize on dev "
420 * blocksize on this device should now be set to the ADFS log2secsize
423 sb->s_magic = ADFS_SUPER_MAGIC;
424 asb->s_idlen = dr->idlen;
425 asb->s_map_size = dr->nzones | (dr->nzones_high << 8);
426 asb->s_map2blk = dr->log2bpmb - dr->log2secsize;
427 asb->s_size = adfs_discsize(dr, sb->s_blocksize_bits);
428 asb->s_version = dr->format_version;
429 asb->s_log2sharesize = dr->log2sharesize;
431 asb->s_map = adfs_read_map(sb, dr);
438 * set up enough so that we can read an inode
440 sb->s_op = &adfs_sops;
442 dr = (struct adfs_discrecord *)(asb->s_map[0].dm_bh->b_data + 4);
444 root_obj.parent_id = root_obj.file_id = le32_to_cpu(dr->root);
445 root_obj.name_len = 0;
446 root_obj.loadaddr = 0;
447 root_obj.execaddr = 0;
448 root_obj.size = ADFS_NEWDIR_SIZE;
449 root_obj.attr = ADFS_NDA_DIRECTORY | ADFS_NDA_OWNER_READ |
450 ADFS_NDA_OWNER_WRITE | ADFS_NDA_PUBLIC_READ;
453 * If this is a F+ disk with variable length directories,
454 * get the root_size from the disc record.
456 if (asb->s_version) {
457 root_obj.size = le32_to_cpu(dr->root_size);
458 asb->s_dir = &adfs_fplus_dir_ops;
459 asb->s_namelen = ADFS_FPLUS_NAME_LEN;
461 asb->s_dir = &adfs_f_dir_ops;
462 asb->s_namelen = ADFS_F_NAME_LEN;
465 root = adfs_iget(sb, &root_obj);
466 sb->s_root = d_alloc_root(root);
470 for (i = 0; i < asb->s_map_size; i++)
471 brelse(asb->s_map[i].dm_bh);
473 adfs_error(sb, "get root inode failed\n");
476 sb->s_root->d_op = &adfs_dentry_operations;
482 sb->s_fs_info = NULL;
487 static int adfs_get_sb(struct file_system_type *fs_type,
488 int flags, const char *dev_name, void *data, struct vfsmount *mnt)
490 return get_sb_bdev(fs_type, flags, dev_name, data, adfs_fill_super,
494 static struct file_system_type adfs_fs_type = {
495 .owner = THIS_MODULE,
497 .get_sb = adfs_get_sb,
498 .kill_sb = kill_block_super,
499 .fs_flags = FS_REQUIRES_DEV,
502 static int __init init_adfs_fs(void)
504 int err = init_inodecache();
507 err = register_filesystem(&adfs_fs_type);
512 destroy_inodecache();
517 static void __exit exit_adfs_fs(void)
519 unregister_filesystem(&adfs_fs_type);
520 destroy_inodecache();
523 module_init(init_adfs_fs)
524 module_exit(exit_adfs_fs)
525 MODULE_LICENSE("GPL");