fs/Kconfig: move qnx4 out
[linux-2.6.git] / fs / qnx4 / inode.c
1 /*
2  * QNX4 file system, Linux implementation.
3  *
4  * Version : 0.2.1
5  *
6  * Using parts of the xiafs filesystem.
7  *
8  * History :
9  *
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.
13  */
14
15 #include <linux/module.h>
16 #include <linux/types.h>
17 #include <linux/string.h>
18 #include <linux/errno.h>
19 #include <linux/slab.h>
20 #include <linux/fs.h>
21 #include <linux/qnx4_fs.h>
22 #include <linux/init.h>
23 #include <linux/highuid.h>
24 #include <linux/smp_lock.h>
25 #include <linux/pagemap.h>
26 #include <linux/buffer_head.h>
27 #include <linux/vfs.h>
28 #include <asm/uaccess.h>
29
30 #define QNX4_VERSION  4
31 #define QNX4_BMNAME   ".bitmap"
32
33 static const struct super_operations qnx4_sops;
34
35 #ifdef CONFIG_QNX4FS_RW
36
37 int qnx4_sync_inode(struct inode *inode)
38 {
39         int err = 0;
40 # if 0
41         struct buffer_head *bh;
42
43         bh = qnx4_update_inode(inode);
44         if (bh && buffer_dirty(bh))
45         {
46                 sync_dirty_buffer(bh);
47                 if (buffer_req(bh) && !buffer_uptodate(bh))
48                 {
49                         printk ("IO error syncing qnx4 inode [%s:%08lx]\n",
50                                 inode->i_sb->s_id, inode->i_ino);
51                         err = -1;
52                 }
53                 brelse (bh);
54         } else if (!bh) {
55                 err = -1;
56         }
57 # endif
58
59         return err;
60 }
61
62 static void qnx4_delete_inode(struct inode *inode)
63 {
64         QNX4DEBUG(("qnx4: deleting inode [%lu]\n", (unsigned long) inode->i_ino));
65         truncate_inode_pages(&inode->i_data, 0);
66         inode->i_size = 0;
67         qnx4_truncate(inode);
68         lock_kernel();
69         qnx4_free_inode(inode);
70         unlock_kernel();
71 }
72
73 static void qnx4_write_super(struct super_block *sb)
74 {
75         lock_kernel();
76         QNX4DEBUG(("qnx4: write_super\n"));
77         sb->s_dirt = 0;
78         unlock_kernel();
79 }
80
81 static int qnx4_write_inode(struct inode *inode, int unused)
82 {
83         struct qnx4_inode_entry *raw_inode;
84         int block, ino;
85         struct buffer_head *bh;
86         ino = inode->i_ino;
87
88         QNX4DEBUG(("qnx4: write inode 1.\n"));
89         if (inode->i_nlink == 0) {
90                 return 0;
91         }
92         if (!ino) {
93                 printk("qnx4: bad inode number on dev %s: %d is out of range\n",
94                        inode->i_sb->s_id, ino);
95                 return -EIO;
96         }
97         QNX4DEBUG(("qnx4: write inode 2.\n"));
98         block = ino / QNX4_INODES_PER_BLOCK;
99         lock_kernel();
100         if (!(bh = sb_bread(inode->i_sb, block))) {
101                 printk("qnx4: major problem: unable to read inode from dev "
102                        "%s\n", inode->i_sb->s_id);
103                 unlock_kernel();
104                 return -EIO;
105         }
106         raw_inode = ((struct qnx4_inode_entry *) bh->b_data) +
107             (ino % QNX4_INODES_PER_BLOCK);
108         raw_inode->di_mode  = cpu_to_le16(inode->i_mode);
109         raw_inode->di_uid   = cpu_to_le16(fs_high2lowuid(inode->i_uid));
110         raw_inode->di_gid   = cpu_to_le16(fs_high2lowgid(inode->i_gid));
111         raw_inode->di_nlink = cpu_to_le16(inode->i_nlink);
112         raw_inode->di_size  = cpu_to_le32(inode->i_size);
113         raw_inode->di_mtime = cpu_to_le32(inode->i_mtime.tv_sec);
114         raw_inode->di_atime = cpu_to_le32(inode->i_atime.tv_sec);
115         raw_inode->di_ctime = cpu_to_le32(inode->i_ctime.tv_sec);
116         raw_inode->di_first_xtnt.xtnt_size = cpu_to_le32(inode->i_blocks);
117         mark_buffer_dirty(bh);
118         brelse(bh);
119         unlock_kernel();
120         return 0;
121 }
122
123 #endif
124
125 static void qnx4_put_super(struct super_block *sb);
126 static struct inode *qnx4_alloc_inode(struct super_block *sb);
127 static void qnx4_destroy_inode(struct inode *inode);
128 static int qnx4_remount(struct super_block *sb, int *flags, char *data);
129 static int qnx4_statfs(struct dentry *, struct kstatfs *);
130
131 static const struct super_operations qnx4_sops =
132 {
133         .alloc_inode    = qnx4_alloc_inode,
134         .destroy_inode  = qnx4_destroy_inode,
135         .put_super      = qnx4_put_super,
136         .statfs         = qnx4_statfs,
137         .remount_fs     = qnx4_remount,
138 #ifdef CONFIG_QNX4FS_RW
139         .write_inode    = qnx4_write_inode,
140         .delete_inode   = qnx4_delete_inode,
141         .write_super    = qnx4_write_super,
142 #endif
143 };
144
145 static int qnx4_remount(struct super_block *sb, int *flags, char *data)
146 {
147         struct qnx4_sb_info *qs;
148
149         qs = qnx4_sb(sb);
150         qs->Version = QNX4_VERSION;
151 #ifndef CONFIG_QNX4FS_RW
152         *flags |= MS_RDONLY;
153 #endif
154         if (*flags & MS_RDONLY) {
155                 return 0;
156         }
157
158         mark_buffer_dirty(qs->sb_buf);
159
160         return 0;
161 }
162
163 static struct buffer_head *qnx4_getblk(struct inode *inode, int nr,
164                                        int create)
165 {
166         struct buffer_head *result = NULL;
167
168         if ( nr >= 0 )
169                 nr = qnx4_block_map( inode, nr );
170         if (nr) {
171                 result = sb_getblk(inode->i_sb, nr);
172                 return result;
173         }
174         if (!create) {
175                 return NULL;
176         }
177 #if 0
178         tmp = qnx4_new_block(inode->i_sb);
179         if (!tmp) {
180                 return NULL;
181         }
182         result = sb_getblk(inode->i_sb, tmp);
183         if (tst) {
184                 qnx4_free_block(inode->i_sb, tmp);
185                 brelse(result);
186                 goto repeat;
187         }
188         tst = tmp;
189 #endif
190         inode->i_ctime = CURRENT_TIME_SEC;
191         mark_inode_dirty(inode);
192         return result;
193 }
194
195 struct buffer_head *qnx4_bread(struct inode *inode, int block, int create)
196 {
197         struct buffer_head *bh;
198
199         bh = qnx4_getblk(inode, block, create);
200         if (!bh || buffer_uptodate(bh)) {
201                 return bh;
202         }
203         ll_rw_block(READ, 1, &bh);
204         wait_on_buffer(bh);
205         if (buffer_uptodate(bh)) {
206                 return bh;
207         }
208         brelse(bh);
209
210         return NULL;
211 }
212
213 static int qnx4_get_block( struct inode *inode, sector_t iblock, struct buffer_head *bh, int create )
214 {
215         unsigned long phys;
216
217         QNX4DEBUG(("qnx4: qnx4_get_block inode=[%ld] iblock=[%ld]\n",inode->i_ino,iblock));
218
219         phys = qnx4_block_map( inode, iblock );
220         if ( phys ) {
221                 // logical block is before EOF
222                 map_bh(bh, inode->i_sb, phys);
223         } else if ( create ) {
224                 // to be done.
225         }
226         return 0;
227 }
228
229 unsigned long qnx4_block_map( struct inode *inode, long iblock )
230 {
231         int ix;
232         long offset, i_xblk;
233         unsigned long block = 0;
234         struct buffer_head *bh = NULL;
235         struct qnx4_xblk *xblk = NULL;
236         struct qnx4_inode_entry *qnx4_inode = qnx4_raw_inode(inode);
237         u16 nxtnt = le16_to_cpu(qnx4_inode->di_num_xtnts);
238
239         if ( iblock < le32_to_cpu(qnx4_inode->di_first_xtnt.xtnt_size) ) {
240                 // iblock is in the first extent. This is easy.
241                 block = le32_to_cpu(qnx4_inode->di_first_xtnt.xtnt_blk) + iblock - 1;
242         } else {
243                 // iblock is beyond first extent. We have to follow the extent chain.
244                 i_xblk = le32_to_cpu(qnx4_inode->di_xblk);
245                 offset = iblock - le32_to_cpu(qnx4_inode->di_first_xtnt.xtnt_size);
246                 ix = 0;
247                 while ( --nxtnt > 0 ) {
248                         if ( ix == 0 ) {
249                                 // read next xtnt block.
250                                 bh = sb_bread(inode->i_sb, i_xblk - 1);
251                                 if ( !bh ) {
252                                         QNX4DEBUG(("qnx4: I/O error reading xtnt block [%ld])\n", i_xblk - 1));
253                                         return -EIO;
254                                 }
255                                 xblk = (struct qnx4_xblk*)bh->b_data;
256                                 if ( memcmp( xblk->xblk_signature, "IamXblk", 7 ) ) {
257                                         QNX4DEBUG(("qnx4: block at %ld is not a valid xtnt\n", qnx4_inode->i_xblk));
258                                         return -EIO;
259                                 }
260                         }
261                         if ( offset < le32_to_cpu(xblk->xblk_xtnts[ix].xtnt_size) ) {
262                                 // got it!
263                                 block = le32_to_cpu(xblk->xblk_xtnts[ix].xtnt_blk) + offset - 1;
264                                 break;
265                         }
266                         offset -= le32_to_cpu(xblk->xblk_xtnts[ix].xtnt_size);
267                         if ( ++ix >= xblk->xblk_num_xtnts ) {
268                                 i_xblk = le32_to_cpu(xblk->xblk_next_xblk);
269                                 ix = 0;
270                                 brelse( bh );
271                                 bh = NULL;
272                         }
273                 }
274                 if ( bh )
275                         brelse( bh );
276         }
277
278         QNX4DEBUG(("qnx4: mapping block %ld of inode %ld = %ld\n",iblock,inode->i_ino,block));
279         return block;
280 }
281
282 static int qnx4_statfs(struct dentry *dentry, struct kstatfs *buf)
283 {
284         struct super_block *sb = dentry->d_sb;
285
286         lock_kernel();
287
288         buf->f_type    = sb->s_magic;
289         buf->f_bsize   = sb->s_blocksize;
290         buf->f_blocks  = le32_to_cpu(qnx4_sb(sb)->BitMap->di_size) * 8;
291         buf->f_bfree   = qnx4_count_free_blocks(sb);
292         buf->f_bavail  = buf->f_bfree;
293         buf->f_namelen = QNX4_NAME_MAX;
294
295         unlock_kernel();
296
297         return 0;
298 }
299
300 /*
301  * Check the root directory of the filesystem to make sure
302  * it really _is_ a qnx4 filesystem, and to check the size
303  * of the directory entry.
304  */
305 static const char *qnx4_checkroot(struct super_block *sb)
306 {
307         struct buffer_head *bh;
308         struct qnx4_inode_entry *rootdir;
309         int rd, rl;
310         int i, j;
311         int found = 0;
312
313         if (*(qnx4_sb(sb)->sb->RootDir.di_fname) != '/') {
314                 return "no qnx4 filesystem (no root dir).";
315         } else {
316                 QNX4DEBUG(("QNX4 filesystem found on dev %s.\n", sb->s_id));
317                 rd = le32_to_cpu(qnx4_sb(sb)->sb->RootDir.di_first_xtnt.xtnt_blk) - 1;
318                 rl = le32_to_cpu(qnx4_sb(sb)->sb->RootDir.di_first_xtnt.xtnt_size);
319                 for (j = 0; j < rl; j++) {
320                         bh = sb_bread(sb, rd + j);      /* root dir, first block */
321                         if (bh == NULL) {
322                                 return "unable to read root entry.";
323                         }
324                         for (i = 0; i < QNX4_INODES_PER_BLOCK; i++) {
325                                 rootdir = (struct qnx4_inode_entry *) (bh->b_data + i * QNX4_DIR_ENTRY_SIZE);
326                                 if (rootdir->di_fname != NULL) {
327                                         QNX4DEBUG(("Rootdir entry found : [%s]\n", rootdir->di_fname));
328                                         if (!strncmp(rootdir->di_fname, QNX4_BMNAME, sizeof QNX4_BMNAME)) {
329                                                 found = 1;
330                                                 qnx4_sb(sb)->BitMap = kmalloc( sizeof( struct qnx4_inode_entry ), GFP_KERNEL );
331                                                 if (!qnx4_sb(sb)->BitMap) {
332                                                         brelse (bh);
333                                                         return "not enough memory for bitmap inode";
334                                                 }
335                                                 memcpy( qnx4_sb(sb)->BitMap, rootdir, sizeof( struct qnx4_inode_entry ) );      /* keep bitmap inode known */
336                                                 break;
337                                         }
338                                 }
339                         }
340                         brelse(bh);
341                         if (found != 0) {
342                                 break;
343                         }
344                 }
345                 if (found == 0) {
346                         return "bitmap file not found.";
347                 }
348         }
349         return NULL;
350 }
351
352 static int qnx4_fill_super(struct super_block *s, void *data, int silent)
353 {
354         struct buffer_head *bh;
355         struct inode *root;
356         const char *errmsg;
357         struct qnx4_sb_info *qs;
358         int ret = -EINVAL;
359
360         qs = kzalloc(sizeof(struct qnx4_sb_info), GFP_KERNEL);
361         if (!qs)
362                 return -ENOMEM;
363         s->s_fs_info = qs;
364
365         sb_set_blocksize(s, QNX4_BLOCK_SIZE);
366
367         /* Check the superblock signature. Since the qnx4 code is
368            dangerous, we should leave as quickly as possible
369            if we don't belong here... */
370         bh = sb_bread(s, 1);
371         if (!bh) {
372                 printk("qnx4: unable to read the superblock\n");
373                 goto outnobh;
374         }
375         if ( le32_to_cpup((__le32*) bh->b_data) != QNX4_SUPER_MAGIC ) {
376                 if (!silent)
377                         printk("qnx4: wrong fsid in superblock.\n");
378                 goto out;
379         }
380         s->s_op = &qnx4_sops;
381         s->s_magic = QNX4_SUPER_MAGIC;
382 #ifndef CONFIG_QNX4FS_RW
383         s->s_flags |= MS_RDONLY;        /* Yup, read-only yet */
384 #endif
385         qnx4_sb(s)->sb_buf = bh;
386         qnx4_sb(s)->sb = (struct qnx4_super_block *) bh->b_data;
387
388
389         /* check before allocating dentries, inodes, .. */
390         errmsg = qnx4_checkroot(s);
391         if (errmsg != NULL) {
392                 if (!silent)
393                         printk("qnx4: %s\n", errmsg);
394                 goto out;
395         }
396
397         /* does root not have inode number QNX4_ROOT_INO ?? */
398         root = qnx4_iget(s, QNX4_ROOT_INO * QNX4_INODES_PER_BLOCK);
399         if (IS_ERR(root)) {
400                 printk("qnx4: get inode failed\n");
401                 ret = PTR_ERR(root);
402                 goto out;
403         }
404
405         ret = -ENOMEM;
406         s->s_root = d_alloc_root(root);
407         if (s->s_root == NULL)
408                 goto outi;
409
410         brelse(bh);
411
412         return 0;
413
414       outi:
415         iput(root);
416       out:
417         brelse(bh);
418       outnobh:
419         kfree(qs);
420         s->s_fs_info = NULL;
421         return ret;
422 }
423
424 static void qnx4_put_super(struct super_block *sb)
425 {
426         struct qnx4_sb_info *qs = qnx4_sb(sb);
427         kfree( qs->BitMap );
428         kfree( qs );
429         sb->s_fs_info = NULL;
430         return;
431 }
432
433 static int qnx4_writepage(struct page *page, struct writeback_control *wbc)
434 {
435         return block_write_full_page(page,qnx4_get_block, wbc);
436 }
437
438 static int qnx4_readpage(struct file *file, struct page *page)
439 {
440         return block_read_full_page(page,qnx4_get_block);
441 }
442
443 static int qnx4_write_begin(struct file *file, struct address_space *mapping,
444                         loff_t pos, unsigned len, unsigned flags,
445                         struct page **pagep, void **fsdata)
446 {
447         struct qnx4_inode_info *qnx4_inode = qnx4_i(mapping->host);
448         *pagep = NULL;
449         return cont_write_begin(file, mapping, pos, len, flags, pagep, fsdata,
450                                 qnx4_get_block,
451                                 &qnx4_inode->mmu_private);
452 }
453 static sector_t qnx4_bmap(struct address_space *mapping, sector_t block)
454 {
455         return generic_block_bmap(mapping,block,qnx4_get_block);
456 }
457 static const struct address_space_operations qnx4_aops = {
458         .readpage       = qnx4_readpage,
459         .writepage      = qnx4_writepage,
460         .sync_page      = block_sync_page,
461         .write_begin    = qnx4_write_begin,
462         .write_end      = generic_write_end,
463         .bmap           = qnx4_bmap
464 };
465
466 struct inode *qnx4_iget(struct super_block *sb, unsigned long ino)
467 {
468         struct buffer_head *bh;
469         struct qnx4_inode_entry *raw_inode;
470         int block;
471         struct qnx4_inode_entry *qnx4_inode;
472         struct inode *inode;
473
474         inode = iget_locked(sb, ino);
475         if (!inode)
476                 return ERR_PTR(-ENOMEM);
477         if (!(inode->i_state & I_NEW))
478                 return inode;
479
480         qnx4_inode = qnx4_raw_inode(inode);
481         inode->i_mode = 0;
482
483         QNX4DEBUG(("Reading inode : [%d]\n", ino));
484         if (!ino) {
485                 printk(KERN_ERR "qnx4: bad inode number on dev %s: %lu is "
486                                 "out of range\n",
487                        sb->s_id, ino);
488                 iget_failed(inode);
489                 return ERR_PTR(-EIO);
490         }
491         block = ino / QNX4_INODES_PER_BLOCK;
492
493         if (!(bh = sb_bread(sb, block))) {
494                 printk("qnx4: major problem: unable to read inode from dev "
495                        "%s\n", sb->s_id);
496                 iget_failed(inode);
497                 return ERR_PTR(-EIO);
498         }
499         raw_inode = ((struct qnx4_inode_entry *) bh->b_data) +
500             (ino % QNX4_INODES_PER_BLOCK);
501
502         inode->i_mode    = le16_to_cpu(raw_inode->di_mode);
503         inode->i_uid     = (uid_t)le16_to_cpu(raw_inode->di_uid);
504         inode->i_gid     = (gid_t)le16_to_cpu(raw_inode->di_gid);
505         inode->i_nlink   = le16_to_cpu(raw_inode->di_nlink);
506         inode->i_size    = le32_to_cpu(raw_inode->di_size);
507         inode->i_mtime.tv_sec   = le32_to_cpu(raw_inode->di_mtime);
508         inode->i_mtime.tv_nsec = 0;
509         inode->i_atime.tv_sec   = le32_to_cpu(raw_inode->di_atime);
510         inode->i_atime.tv_nsec = 0;
511         inode->i_ctime.tv_sec   = le32_to_cpu(raw_inode->di_ctime);
512         inode->i_ctime.tv_nsec = 0;
513         inode->i_blocks  = le32_to_cpu(raw_inode->di_first_xtnt.xtnt_size);
514
515         memcpy(qnx4_inode, raw_inode, QNX4_DIR_ENTRY_SIZE);
516         if (S_ISREG(inode->i_mode)) {
517                 inode->i_op = &qnx4_file_inode_operations;
518                 inode->i_fop = &qnx4_file_operations;
519                 inode->i_mapping->a_ops = &qnx4_aops;
520                 qnx4_i(inode)->mmu_private = inode->i_size;
521         } else if (S_ISDIR(inode->i_mode)) {
522                 inode->i_op = &qnx4_dir_inode_operations;
523                 inode->i_fop = &qnx4_dir_operations;
524         } else if (S_ISLNK(inode->i_mode)) {
525                 inode->i_op = &page_symlink_inode_operations;
526                 inode->i_mapping->a_ops = &qnx4_aops;
527                 qnx4_i(inode)->mmu_private = inode->i_size;
528         } else {
529                 printk(KERN_ERR "qnx4: bad inode %lu on dev %s\n",
530                         ino, sb->s_id);
531                 iget_failed(inode);
532                 brelse(bh);
533                 return ERR_PTR(-EIO);
534         }
535         brelse(bh);
536         unlock_new_inode(inode);
537         return inode;
538 }
539
540 static struct kmem_cache *qnx4_inode_cachep;
541
542 static struct inode *qnx4_alloc_inode(struct super_block *sb)
543 {
544         struct qnx4_inode_info *ei;
545         ei = kmem_cache_alloc(qnx4_inode_cachep, GFP_KERNEL);
546         if (!ei)
547                 return NULL;
548         return &ei->vfs_inode;
549 }
550
551 static void qnx4_destroy_inode(struct inode *inode)
552 {
553         kmem_cache_free(qnx4_inode_cachep, qnx4_i(inode));
554 }
555
556 static void init_once(void *foo)
557 {
558         struct qnx4_inode_info *ei = (struct qnx4_inode_info *) foo;
559
560         inode_init_once(&ei->vfs_inode);
561 }
562
563 static int init_inodecache(void)
564 {
565         qnx4_inode_cachep = kmem_cache_create("qnx4_inode_cache",
566                                              sizeof(struct qnx4_inode_info),
567                                              0, (SLAB_RECLAIM_ACCOUNT|
568                                                 SLAB_MEM_SPREAD),
569                                              init_once);
570         if (qnx4_inode_cachep == NULL)
571                 return -ENOMEM;
572         return 0;
573 }
574
575 static void destroy_inodecache(void)
576 {
577         kmem_cache_destroy(qnx4_inode_cachep);
578 }
579
580 static int qnx4_get_sb(struct file_system_type *fs_type,
581         int flags, const char *dev_name, void *data, struct vfsmount *mnt)
582 {
583         return get_sb_bdev(fs_type, flags, dev_name, data, qnx4_fill_super,
584                            mnt);
585 }
586
587 static struct file_system_type qnx4_fs_type = {
588         .owner          = THIS_MODULE,
589         .name           = "qnx4",
590         .get_sb         = qnx4_get_sb,
591         .kill_sb        = kill_block_super,
592         .fs_flags       = FS_REQUIRES_DEV,
593 };
594
595 static int __init init_qnx4_fs(void)
596 {
597         int err;
598
599         err = init_inodecache();
600         if (err)
601                 return err;
602
603         err = register_filesystem(&qnx4_fs_type);
604         if (err) {
605                 destroy_inodecache();
606                 return err;
607         }
608
609         printk("QNX4 filesystem 0.2.3 registered.\n");
610         return 0;
611 }
612
613 static void __exit exit_qnx4_fs(void)
614 {
615         unregister_filesystem(&qnx4_fs_type);
616         destroy_inodecache();
617 }
618
619 module_init(init_qnx4_fs)
620 module_exit(exit_qnx4_fs)
621 MODULE_LICENSE("GPL");
622