2 * QNX4 file system, Linux implementation.
6 * Using parts of the xiafs filesystem.
10 * 01-06-1998 by Richard Frowijn : first release.
11 * 20-06-1998 by Frank Denis : Linux 2.1.99+ support, boot signature, misc.
12 * 30-06-1998 by Frank Denis : first step to write inodes.
15 #include <linux/module.h>
16 #include <linux/init.h>
17 #include <linux/slab.h>
18 #include <linux/highuid.h>
19 #include <linux/pagemap.h>
20 #include <linux/buffer_head.h>
21 #include <linux/writeback.h>
22 #include <linux/statfs.h>
25 #define QNX4_VERSION 4
26 #define QNX4_BMNAME ".bitmap"
28 static const struct super_operations qnx4_sops;
30 static void qnx4_put_super(struct super_block *sb);
31 static struct inode *qnx4_alloc_inode(struct super_block *sb);
32 static void qnx4_destroy_inode(struct inode *inode);
33 static int qnx4_remount(struct super_block *sb, int *flags, char *data);
34 static int qnx4_statfs(struct dentry *, struct kstatfs *);
36 static const struct super_operations qnx4_sops =
38 .alloc_inode = qnx4_alloc_inode,
39 .destroy_inode = qnx4_destroy_inode,
40 .put_super = qnx4_put_super,
41 .statfs = qnx4_statfs,
42 .remount_fs = qnx4_remount,
45 static int qnx4_remount(struct super_block *sb, int *flags, char *data)
47 struct qnx4_sb_info *qs;
50 qs->Version = QNX4_VERSION;
55 static struct buffer_head *qnx4_getblk(struct inode *inode, int nr,
58 struct buffer_head *result = NULL;
61 nr = qnx4_block_map( inode, nr );
63 result = sb_getblk(inode->i_sb, nr);
69 struct buffer_head *qnx4_bread(struct inode *inode, int block, int create)
71 struct buffer_head *bh;
73 bh = qnx4_getblk(inode, block, create);
74 if (!bh || buffer_uptodate(bh)) {
77 ll_rw_block(READ, 1, &bh);
79 if (buffer_uptodate(bh)) {
87 static int qnx4_get_block( struct inode *inode, sector_t iblock, struct buffer_head *bh, int create )
91 QNX4DEBUG((KERN_INFO "qnx4: qnx4_get_block inode=[%ld] iblock=[%ld]\n",inode->i_ino,iblock));
93 phys = qnx4_block_map( inode, iblock );
95 // logical block is before EOF
96 map_bh(bh, inode->i_sb, phys);
101 unsigned long qnx4_block_map( struct inode *inode, long iblock )
105 unsigned long block = 0;
106 struct buffer_head *bh = NULL;
107 struct qnx4_xblk *xblk = NULL;
108 struct qnx4_inode_entry *qnx4_inode = qnx4_raw_inode(inode);
109 u16 nxtnt = le16_to_cpu(qnx4_inode->di_num_xtnts);
111 if ( iblock < le32_to_cpu(qnx4_inode->di_first_xtnt.xtnt_size) ) {
112 // iblock is in the first extent. This is easy.
113 block = le32_to_cpu(qnx4_inode->di_first_xtnt.xtnt_blk) + iblock - 1;
115 // iblock is beyond first extent. We have to follow the extent chain.
116 i_xblk = le32_to_cpu(qnx4_inode->di_xblk);
117 offset = iblock - le32_to_cpu(qnx4_inode->di_first_xtnt.xtnt_size);
119 while ( --nxtnt > 0 ) {
121 // read next xtnt block.
122 bh = sb_bread(inode->i_sb, i_xblk - 1);
124 QNX4DEBUG((KERN_ERR "qnx4: I/O error reading xtnt block [%ld])\n", i_xblk - 1));
127 xblk = (struct qnx4_xblk*)bh->b_data;
128 if ( memcmp( xblk->xblk_signature, "IamXblk", 7 ) ) {
129 QNX4DEBUG((KERN_ERR "qnx4: block at %ld is not a valid xtnt\n", qnx4_inode->i_xblk));
133 if ( offset < le32_to_cpu(xblk->xblk_xtnts[ix].xtnt_size) ) {
135 block = le32_to_cpu(xblk->xblk_xtnts[ix].xtnt_blk) + offset - 1;
138 offset -= le32_to_cpu(xblk->xblk_xtnts[ix].xtnt_size);
139 if ( ++ix >= xblk->xblk_num_xtnts ) {
140 i_xblk = le32_to_cpu(xblk->xblk_next_xblk);
150 QNX4DEBUG((KERN_INFO "qnx4: mapping block %ld of inode %ld = %ld\n",iblock,inode->i_ino,block));
154 static int qnx4_statfs(struct dentry *dentry, struct kstatfs *buf)
156 struct super_block *sb = dentry->d_sb;
157 u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
159 buf->f_type = sb->s_magic;
160 buf->f_bsize = sb->s_blocksize;
161 buf->f_blocks = le32_to_cpu(qnx4_sb(sb)->BitMap->di_size) * 8;
162 buf->f_bfree = qnx4_count_free_blocks(sb);
163 buf->f_bavail = buf->f_bfree;
164 buf->f_namelen = QNX4_NAME_MAX;
165 buf->f_fsid.val[0] = (u32)id;
166 buf->f_fsid.val[1] = (u32)(id >> 32);
172 * Check the root directory of the filesystem to make sure
173 * it really _is_ a qnx4 filesystem, and to check the size
174 * of the directory entry.
176 static const char *qnx4_checkroot(struct super_block *sb)
178 struct buffer_head *bh;
179 struct qnx4_inode_entry *rootdir;
183 if (*(qnx4_sb(sb)->sb->RootDir.di_fname) != '/')
184 return "no qnx4 filesystem (no root dir).";
185 QNX4DEBUG((KERN_NOTICE "QNX4 filesystem found on dev %s.\n", sb->s_id));
186 rd = le32_to_cpu(qnx4_sb(sb)->sb->RootDir.di_first_xtnt.xtnt_blk) - 1;
187 rl = le32_to_cpu(qnx4_sb(sb)->sb->RootDir.di_first_xtnt.xtnt_size);
188 for (j = 0; j < rl; j++) {
189 bh = sb_bread(sb, rd + j); /* root dir, first block */
191 return "unable to read root entry.";
192 rootdir = (struct qnx4_inode_entry *) bh->b_data;
193 for (i = 0; i < QNX4_INODES_PER_BLOCK; i++, rootdir++) {
194 QNX4DEBUG((KERN_INFO "rootdir entry found : [%s]\n", rootdir->di_fname));
195 if (strcmp(rootdir->di_fname, QNX4_BMNAME) != 0)
197 qnx4_sb(sb)->BitMap = kmemdup(rootdir,
198 sizeof(struct qnx4_inode_entry),
201 if (!qnx4_sb(sb)->BitMap)
202 return "not enough memory for bitmap inode";
203 /* keep bitmap inode known */
208 return "bitmap file not found.";
211 static int qnx4_fill_super(struct super_block *s, void *data, int silent)
213 struct buffer_head *bh;
216 struct qnx4_sb_info *qs;
219 qs = kzalloc(sizeof(struct qnx4_sb_info), GFP_KERNEL);
224 sb_set_blocksize(s, QNX4_BLOCK_SIZE);
226 /* Check the superblock signature. Since the qnx4 code is
227 dangerous, we should leave as quickly as possible
228 if we don't belong here... */
231 printk(KERN_ERR "qnx4: unable to read the superblock\n");
234 if ( le32_to_cpup((__le32*) bh->b_data) != QNX4_SUPER_MAGIC ) {
236 printk(KERN_ERR "qnx4: wrong fsid in superblock.\n");
239 s->s_op = &qnx4_sops;
240 s->s_magic = QNX4_SUPER_MAGIC;
241 s->s_flags |= MS_RDONLY; /* Yup, read-only yet */
242 qnx4_sb(s)->sb_buf = bh;
243 qnx4_sb(s)->sb = (struct qnx4_super_block *) bh->b_data;
246 /* check before allocating dentries, inodes, .. */
247 errmsg = qnx4_checkroot(s);
248 if (errmsg != NULL) {
250 printk(KERN_ERR "qnx4: %s\n", errmsg);
254 /* does root not have inode number QNX4_ROOT_INO ?? */
255 root = qnx4_iget(s, QNX4_ROOT_INO * QNX4_INODES_PER_BLOCK);
257 printk(KERN_ERR "qnx4: get inode failed\n");
263 s->s_root = d_make_root(root);
264 if (s->s_root == NULL)
280 static void qnx4_put_super(struct super_block *sb)
282 struct qnx4_sb_info *qs = qnx4_sb(sb);
285 sb->s_fs_info = NULL;
289 static int qnx4_readpage(struct file *file, struct page *page)
291 return block_read_full_page(page,qnx4_get_block);
294 static sector_t qnx4_bmap(struct address_space *mapping, sector_t block)
296 return generic_block_bmap(mapping,block,qnx4_get_block);
298 static const struct address_space_operations qnx4_aops = {
299 .readpage = qnx4_readpage,
303 struct inode *qnx4_iget(struct super_block *sb, unsigned long ino)
305 struct buffer_head *bh;
306 struct qnx4_inode_entry *raw_inode;
308 struct qnx4_inode_entry *qnx4_inode;
311 inode = iget_locked(sb, ino);
313 return ERR_PTR(-ENOMEM);
314 if (!(inode->i_state & I_NEW))
317 qnx4_inode = qnx4_raw_inode(inode);
320 QNX4DEBUG((KERN_INFO "reading inode : [%d]\n", ino));
322 printk(KERN_ERR "qnx4: bad inode number on dev %s: %lu is "
326 return ERR_PTR(-EIO);
328 block = ino / QNX4_INODES_PER_BLOCK;
330 if (!(bh = sb_bread(sb, block))) {
331 printk(KERN_ERR "qnx4: major problem: unable to read inode from dev "
334 return ERR_PTR(-EIO);
336 raw_inode = ((struct qnx4_inode_entry *) bh->b_data) +
337 (ino % QNX4_INODES_PER_BLOCK);
339 inode->i_mode = le16_to_cpu(raw_inode->di_mode);
340 inode->i_uid = (uid_t)le16_to_cpu(raw_inode->di_uid);
341 inode->i_gid = (gid_t)le16_to_cpu(raw_inode->di_gid);
342 set_nlink(inode, le16_to_cpu(raw_inode->di_nlink));
343 inode->i_size = le32_to_cpu(raw_inode->di_size);
344 inode->i_mtime.tv_sec = le32_to_cpu(raw_inode->di_mtime);
345 inode->i_mtime.tv_nsec = 0;
346 inode->i_atime.tv_sec = le32_to_cpu(raw_inode->di_atime);
347 inode->i_atime.tv_nsec = 0;
348 inode->i_ctime.tv_sec = le32_to_cpu(raw_inode->di_ctime);
349 inode->i_ctime.tv_nsec = 0;
350 inode->i_blocks = le32_to_cpu(raw_inode->di_first_xtnt.xtnt_size);
352 memcpy(qnx4_inode, raw_inode, QNX4_DIR_ENTRY_SIZE);
353 if (S_ISREG(inode->i_mode)) {
354 inode->i_fop = &generic_ro_fops;
355 inode->i_mapping->a_ops = &qnx4_aops;
356 qnx4_i(inode)->mmu_private = inode->i_size;
357 } else if (S_ISDIR(inode->i_mode)) {
358 inode->i_op = &qnx4_dir_inode_operations;
359 inode->i_fop = &qnx4_dir_operations;
360 } else if (S_ISLNK(inode->i_mode)) {
361 inode->i_op = &page_symlink_inode_operations;
362 inode->i_mapping->a_ops = &qnx4_aops;
363 qnx4_i(inode)->mmu_private = inode->i_size;
365 printk(KERN_ERR "qnx4: bad inode %lu on dev %s\n",
369 return ERR_PTR(-EIO);
372 unlock_new_inode(inode);
376 static struct kmem_cache *qnx4_inode_cachep;
378 static struct inode *qnx4_alloc_inode(struct super_block *sb)
380 struct qnx4_inode_info *ei;
381 ei = kmem_cache_alloc(qnx4_inode_cachep, GFP_KERNEL);
384 return &ei->vfs_inode;
387 static void qnx4_i_callback(struct rcu_head *head)
389 struct inode *inode = container_of(head, struct inode, i_rcu);
390 kmem_cache_free(qnx4_inode_cachep, qnx4_i(inode));
393 static void qnx4_destroy_inode(struct inode *inode)
395 call_rcu(&inode->i_rcu, qnx4_i_callback);
398 static void init_once(void *foo)
400 struct qnx4_inode_info *ei = (struct qnx4_inode_info *) foo;
402 inode_init_once(&ei->vfs_inode);
405 static int init_inodecache(void)
407 qnx4_inode_cachep = kmem_cache_create("qnx4_inode_cache",
408 sizeof(struct qnx4_inode_info),
409 0, (SLAB_RECLAIM_ACCOUNT|
412 if (qnx4_inode_cachep == NULL)
417 static void destroy_inodecache(void)
419 kmem_cache_destroy(qnx4_inode_cachep);
422 static struct dentry *qnx4_mount(struct file_system_type *fs_type,
423 int flags, const char *dev_name, void *data)
425 return mount_bdev(fs_type, flags, dev_name, data, qnx4_fill_super);
428 static struct file_system_type qnx4_fs_type = {
429 .owner = THIS_MODULE,
432 .kill_sb = kill_block_super,
433 .fs_flags = FS_REQUIRES_DEV,
436 static int __init init_qnx4_fs(void)
440 err = init_inodecache();
444 err = register_filesystem(&qnx4_fs_type);
446 destroy_inodecache();
450 printk(KERN_INFO "QNX4 filesystem 0.2.3 registered.\n");
454 static void __exit exit_qnx4_fs(void)
456 unregister_filesystem(&qnx4_fs_type);
457 destroy_inodecache();
460 module_init(init_qnx4_fs)
461 module_exit(exit_qnx4_fs)
462 MODULE_LICENSE("GPL");