ia64/linux-2.6.18-xen.hg

view fs/qnx4/inode.c @ 524:7f8b544237bf

netfront: Allow netfront in domain 0.

This is useful if your physical network device is in a utility domain.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
author Keir Fraser <keir.fraser@citrix.com>
date Tue Apr 15 15:18:58 2008 +0100 (2008-04-15)
parents 831230e53067
children
line source
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 */
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>
30 #define QNX4_VERSION 4
31 #define QNX4_BMNAME ".bitmap"
33 static struct super_operations qnx4_sops;
35 #ifdef CONFIG_QNX4FS_RW
37 int qnx4_sync_inode(struct inode *inode)
38 {
39 int err = 0;
40 # if 0
41 struct buffer_head *bh;
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
59 return err;
60 }
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 }
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 }
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;
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 }
123 #endif
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 void qnx4_read_inode(struct inode *);
129 static int qnx4_remount(struct super_block *sb, int *flags, char *data);
130 static int qnx4_statfs(struct dentry *, struct kstatfs *);
132 static struct super_operations qnx4_sops =
133 {
134 .alloc_inode = qnx4_alloc_inode,
135 .destroy_inode = qnx4_destroy_inode,
136 .read_inode = qnx4_read_inode,
137 .put_super = qnx4_put_super,
138 .statfs = qnx4_statfs,
139 .remount_fs = qnx4_remount,
140 #ifdef CONFIG_QNX4FS_RW
141 .write_inode = qnx4_write_inode,
142 .delete_inode = qnx4_delete_inode,
143 .write_super = qnx4_write_super,
144 #endif
145 };
147 static int qnx4_remount(struct super_block *sb, int *flags, char *data)
148 {
149 struct qnx4_sb_info *qs;
151 qs = qnx4_sb(sb);
152 qs->Version = QNX4_VERSION;
153 #ifndef CONFIG_QNX4FS_RW
154 *flags |= MS_RDONLY;
155 #endif
156 if (*flags & MS_RDONLY) {
157 return 0;
158 }
160 mark_buffer_dirty(qs->sb_buf);
162 return 0;
163 }
165 static struct buffer_head *qnx4_getblk(struct inode *inode, int nr,
166 int create)
167 {
168 struct buffer_head *result = NULL;
170 if ( nr >= 0 )
171 nr = qnx4_block_map( inode, nr );
172 if (nr) {
173 result = sb_getblk(inode->i_sb, nr);
174 return result;
175 }
176 if (!create) {
177 return NULL;
178 }
179 #if 0
180 tmp = qnx4_new_block(inode->i_sb);
181 if (!tmp) {
182 return NULL;
183 }
184 result = sb_getblk(inode->i_sb, tmp);
185 if (tst) {
186 qnx4_free_block(inode->i_sb, tmp);
187 brelse(result);
188 goto repeat;
189 }
190 tst = tmp;
191 #endif
192 inode->i_ctime = CURRENT_TIME_SEC;
193 mark_inode_dirty(inode);
194 return result;
195 }
197 struct buffer_head *qnx4_bread(struct inode *inode, int block, int create)
198 {
199 struct buffer_head *bh;
201 bh = qnx4_getblk(inode, block, create);
202 if (!bh || buffer_uptodate(bh)) {
203 return bh;
204 }
205 ll_rw_block(READ, 1, &bh);
206 wait_on_buffer(bh);
207 if (buffer_uptodate(bh)) {
208 return bh;
209 }
210 brelse(bh);
212 return NULL;
213 }
215 static int qnx4_get_block( struct inode *inode, sector_t iblock, struct buffer_head *bh, int create )
216 {
217 unsigned long phys;
219 QNX4DEBUG(("qnx4: qnx4_get_block inode=[%ld] iblock=[%ld]\n",inode->i_ino,iblock));
221 phys = qnx4_block_map( inode, iblock );
222 if ( phys ) {
223 // logical block is before EOF
224 map_bh(bh, inode->i_sb, phys);
225 } else if ( create ) {
226 // to be done.
227 }
228 return 0;
229 }
231 unsigned long qnx4_block_map( struct inode *inode, long iblock )
232 {
233 int ix;
234 long offset, i_xblk;
235 unsigned long block = 0;
236 struct buffer_head *bh = NULL;
237 struct qnx4_xblk *xblk = NULL;
238 struct qnx4_inode_entry *qnx4_inode = qnx4_raw_inode(inode);
239 u16 nxtnt = le16_to_cpu(qnx4_inode->di_num_xtnts);
241 if ( iblock < le32_to_cpu(qnx4_inode->di_first_xtnt.xtnt_size) ) {
242 // iblock is in the first extent. This is easy.
243 block = le32_to_cpu(qnx4_inode->di_first_xtnt.xtnt_blk) + iblock - 1;
244 } else {
245 // iblock is beyond first extent. We have to follow the extent chain.
246 i_xblk = le32_to_cpu(qnx4_inode->di_xblk);
247 offset = iblock - le32_to_cpu(qnx4_inode->di_first_xtnt.xtnt_size);
248 ix = 0;
249 while ( --nxtnt > 0 ) {
250 if ( ix == 0 ) {
251 // read next xtnt block.
252 bh = sb_bread(inode->i_sb, i_xblk - 1);
253 if ( !bh ) {
254 QNX4DEBUG(("qnx4: I/O error reading xtnt block [%ld])\n", i_xblk - 1));
255 return -EIO;
256 }
257 xblk = (struct qnx4_xblk*)bh->b_data;
258 if ( memcmp( xblk->xblk_signature, "IamXblk", 7 ) ) {
259 QNX4DEBUG(("qnx4: block at %ld is not a valid xtnt\n", qnx4_inode->i_xblk));
260 return -EIO;
261 }
262 }
263 if ( offset < le32_to_cpu(xblk->xblk_xtnts[ix].xtnt_size) ) {
264 // got it!
265 block = le32_to_cpu(xblk->xblk_xtnts[ix].xtnt_blk) + offset - 1;
266 break;
267 }
268 offset -= le32_to_cpu(xblk->xblk_xtnts[ix].xtnt_size);
269 if ( ++ix >= xblk->xblk_num_xtnts ) {
270 i_xblk = le32_to_cpu(xblk->xblk_next_xblk);
271 ix = 0;
272 brelse( bh );
273 bh = NULL;
274 }
275 }
276 if ( bh )
277 brelse( bh );
278 }
280 QNX4DEBUG(("qnx4: mapping block %ld of inode %ld = %ld\n",iblock,inode->i_ino,block));
281 return block;
282 }
284 static int qnx4_statfs(struct dentry *dentry, struct kstatfs *buf)
285 {
286 struct super_block *sb = dentry->d_sb;
288 lock_kernel();
290 buf->f_type = sb->s_magic;
291 buf->f_bsize = sb->s_blocksize;
292 buf->f_blocks = le32_to_cpu(qnx4_sb(sb)->BitMap->di_size) * 8;
293 buf->f_bfree = qnx4_count_free_blocks(sb);
294 buf->f_bavail = buf->f_bfree;
295 buf->f_namelen = QNX4_NAME_MAX;
297 unlock_kernel();
299 return 0;
300 }
302 /*
303 * Check the root directory of the filesystem to make sure
304 * it really _is_ a qnx4 filesystem, and to check the size
305 * of the directory entry.
306 */
307 static const char *qnx4_checkroot(struct super_block *sb)
308 {
309 struct buffer_head *bh;
310 struct qnx4_inode_entry *rootdir;
311 int rd, rl;
312 int i, j;
313 int found = 0;
315 if (*(qnx4_sb(sb)->sb->RootDir.di_fname) != '/') {
316 return "no qnx4 filesystem (no root dir).";
317 } else {
318 QNX4DEBUG(("QNX4 filesystem found on dev %s.\n", sb->s_id));
319 rd = le32_to_cpu(qnx4_sb(sb)->sb->RootDir.di_first_xtnt.xtnt_blk) - 1;
320 rl = le32_to_cpu(qnx4_sb(sb)->sb->RootDir.di_first_xtnt.xtnt_size);
321 for (j = 0; j < rl; j++) {
322 bh = sb_bread(sb, rd + j); /* root dir, first block */
323 if (bh == NULL) {
324 return "unable to read root entry.";
325 }
326 for (i = 0; i < QNX4_INODES_PER_BLOCK; i++) {
327 rootdir = (struct qnx4_inode_entry *) (bh->b_data + i * QNX4_DIR_ENTRY_SIZE);
328 if (rootdir->di_fname != NULL) {
329 QNX4DEBUG(("Rootdir entry found : [%s]\n", rootdir->di_fname));
330 if (!strncmp(rootdir->di_fname, QNX4_BMNAME, sizeof QNX4_BMNAME)) {
331 found = 1;
332 qnx4_sb(sb)->BitMap = kmalloc( sizeof( struct qnx4_inode_entry ), GFP_KERNEL );
333 if (!qnx4_sb(sb)->BitMap) {
334 brelse (bh);
335 return "not enough memory for bitmap inode";
336 }
337 memcpy( qnx4_sb(sb)->BitMap, rootdir, sizeof( struct qnx4_inode_entry ) ); /* keep bitmap inode known */
338 break;
339 }
340 }
341 }
342 brelse(bh);
343 if (found != 0) {
344 break;
345 }
346 }
347 if (found == 0) {
348 return "bitmap file not found.";
349 }
350 }
351 return NULL;
352 }
354 static int qnx4_fill_super(struct super_block *s, void *data, int silent)
355 {
356 struct buffer_head *bh;
357 struct inode *root;
358 const char *errmsg;
359 struct qnx4_sb_info *qs;
361 qs = kmalloc(sizeof(struct qnx4_sb_info), GFP_KERNEL);
362 if (!qs)
363 return -ENOMEM;
364 s->s_fs_info = qs;
365 memset(qs, 0, sizeof(struct qnx4_sb_info));
367 sb_set_blocksize(s, QNX4_BLOCK_SIZE);
369 /* Check the superblock signature. Since the qnx4 code is
370 dangerous, we should leave as quickly as possible
371 if we don't belong here... */
372 bh = sb_bread(s, 1);
373 if (!bh) {
374 printk("qnx4: unable to read the superblock\n");
375 goto outnobh;
376 }
377 if ( le32_to_cpup((__le32*) bh->b_data) != QNX4_SUPER_MAGIC ) {
378 if (!silent)
379 printk("qnx4: wrong fsid in superblock.\n");
380 goto out;
381 }
382 s->s_op = &qnx4_sops;
383 s->s_magic = QNX4_SUPER_MAGIC;
384 #ifndef CONFIG_QNX4FS_RW
385 s->s_flags |= MS_RDONLY; /* Yup, read-only yet */
386 #endif
387 qnx4_sb(s)->sb_buf = bh;
388 qnx4_sb(s)->sb = (struct qnx4_super_block *) bh->b_data;
391 /* check before allocating dentries, inodes, .. */
392 errmsg = qnx4_checkroot(s);
393 if (errmsg != NULL) {
394 if (!silent)
395 printk("qnx4: %s\n", errmsg);
396 goto out;
397 }
399 /* does root not have inode number QNX4_ROOT_INO ?? */
400 root = iget(s, QNX4_ROOT_INO * QNX4_INODES_PER_BLOCK);
401 if (!root) {
402 printk("qnx4: get inode failed\n");
403 goto out;
404 }
406 s->s_root = d_alloc_root(root);
407 if (s->s_root == NULL)
408 goto outi;
410 brelse(bh);
412 return 0;
414 outi:
415 iput(root);
416 out:
417 brelse(bh);
418 outnobh:
419 kfree(qs);
420 s->s_fs_info = NULL;
421 return -EINVAL;
422 }
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 }
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 static int qnx4_readpage(struct file *file, struct page *page)
438 {
439 return block_read_full_page(page,qnx4_get_block);
440 }
441 static int qnx4_prepare_write(struct file *file, struct page *page,
442 unsigned from, unsigned to)
443 {
444 struct qnx4_inode_info *qnx4_inode = qnx4_i(page->mapping->host);
445 return cont_prepare_write(page, from, to, qnx4_get_block,
446 &qnx4_inode->mmu_private);
447 }
448 static sector_t qnx4_bmap(struct address_space *mapping, sector_t block)
449 {
450 return generic_block_bmap(mapping,block,qnx4_get_block);
451 }
452 static const struct address_space_operations qnx4_aops = {
453 .readpage = qnx4_readpage,
454 .writepage = qnx4_writepage,
455 .sync_page = block_sync_page,
456 .prepare_write = qnx4_prepare_write,
457 .commit_write = generic_commit_write,
458 .bmap = qnx4_bmap
459 };
461 static void qnx4_read_inode(struct inode *inode)
462 {
463 struct buffer_head *bh;
464 struct qnx4_inode_entry *raw_inode;
465 int block, ino;
466 struct super_block *sb = inode->i_sb;
467 struct qnx4_inode_entry *qnx4_inode = qnx4_raw_inode(inode);
469 ino = inode->i_ino;
470 inode->i_mode = 0;
472 QNX4DEBUG(("Reading inode : [%d]\n", ino));
473 if (!ino) {
474 printk("qnx4: bad inode number on dev %s: %d is out of range\n",
475 sb->s_id, ino);
476 return;
477 }
478 block = ino / QNX4_INODES_PER_BLOCK;
480 if (!(bh = sb_bread(sb, block))) {
481 printk("qnx4: major problem: unable to read inode from dev "
482 "%s\n", sb->s_id);
483 return;
484 }
485 raw_inode = ((struct qnx4_inode_entry *) bh->b_data) +
486 (ino % QNX4_INODES_PER_BLOCK);
488 inode->i_mode = le16_to_cpu(raw_inode->di_mode);
489 inode->i_uid = (uid_t)le16_to_cpu(raw_inode->di_uid);
490 inode->i_gid = (gid_t)le16_to_cpu(raw_inode->di_gid);
491 inode->i_nlink = le16_to_cpu(raw_inode->di_nlink);
492 inode->i_size = le32_to_cpu(raw_inode->di_size);
493 inode->i_mtime.tv_sec = le32_to_cpu(raw_inode->di_mtime);
494 inode->i_mtime.tv_nsec = 0;
495 inode->i_atime.tv_sec = le32_to_cpu(raw_inode->di_atime);
496 inode->i_atime.tv_nsec = 0;
497 inode->i_ctime.tv_sec = le32_to_cpu(raw_inode->di_ctime);
498 inode->i_ctime.tv_nsec = 0;
499 inode->i_blocks = le32_to_cpu(raw_inode->di_first_xtnt.xtnt_size);
500 inode->i_blksize = QNX4_DIR_ENTRY_SIZE;
502 memcpy(qnx4_inode, raw_inode, QNX4_DIR_ENTRY_SIZE);
503 if (S_ISREG(inode->i_mode)) {
504 inode->i_op = &qnx4_file_inode_operations;
505 inode->i_fop = &qnx4_file_operations;
506 inode->i_mapping->a_ops = &qnx4_aops;
507 qnx4_i(inode)->mmu_private = inode->i_size;
508 } else if (S_ISDIR(inode->i_mode)) {
509 inode->i_op = &qnx4_dir_inode_operations;
510 inode->i_fop = &qnx4_dir_operations;
511 } else if (S_ISLNK(inode->i_mode)) {
512 inode->i_op = &page_symlink_inode_operations;
513 inode->i_mapping->a_ops = &qnx4_aops;
514 qnx4_i(inode)->mmu_private = inode->i_size;
515 } else
516 printk("qnx4: bad inode %d on dev %s\n",ino,sb->s_id);
517 brelse(bh);
518 }
520 static kmem_cache_t *qnx4_inode_cachep;
522 static struct inode *qnx4_alloc_inode(struct super_block *sb)
523 {
524 struct qnx4_inode_info *ei;
525 ei = kmem_cache_alloc(qnx4_inode_cachep, SLAB_KERNEL);
526 if (!ei)
527 return NULL;
528 return &ei->vfs_inode;
529 }
531 static void qnx4_destroy_inode(struct inode *inode)
532 {
533 kmem_cache_free(qnx4_inode_cachep, qnx4_i(inode));
534 }
536 static void init_once(void *foo, kmem_cache_t * cachep,
537 unsigned long flags)
538 {
539 struct qnx4_inode_info *ei = (struct qnx4_inode_info *) foo;
541 if ((flags & (SLAB_CTOR_VERIFY | SLAB_CTOR_CONSTRUCTOR)) ==
542 SLAB_CTOR_CONSTRUCTOR)
543 inode_init_once(&ei->vfs_inode);
544 }
546 static int init_inodecache(void)
547 {
548 qnx4_inode_cachep = kmem_cache_create("qnx4_inode_cache",
549 sizeof(struct qnx4_inode_info),
550 0, (SLAB_RECLAIM_ACCOUNT|
551 SLAB_MEM_SPREAD),
552 init_once, NULL);
553 if (qnx4_inode_cachep == NULL)
554 return -ENOMEM;
555 return 0;
556 }
558 static void destroy_inodecache(void)
559 {
560 if (kmem_cache_destroy(qnx4_inode_cachep))
561 printk(KERN_INFO
562 "qnx4_inode_cache: not all structures were freed\n");
563 }
565 static int qnx4_get_sb(struct file_system_type *fs_type,
566 int flags, const char *dev_name, void *data, struct vfsmount *mnt)
567 {
568 return get_sb_bdev(fs_type, flags, dev_name, data, qnx4_fill_super,
569 mnt);
570 }
572 static struct file_system_type qnx4_fs_type = {
573 .owner = THIS_MODULE,
574 .name = "qnx4",
575 .get_sb = qnx4_get_sb,
576 .kill_sb = kill_block_super,
577 .fs_flags = FS_REQUIRES_DEV,
578 };
580 static int __init init_qnx4_fs(void)
581 {
582 int err;
584 err = init_inodecache();
585 if (err)
586 return err;
588 err = register_filesystem(&qnx4_fs_type);
589 if (err) {
590 destroy_inodecache();
591 return err;
592 }
594 printk("QNX4 filesystem 0.2.3 registered.\n");
595 return 0;
596 }
598 static void __exit exit_qnx4_fs(void)
599 {
600 unregister_filesystem(&qnx4_fs_type);
601 destroy_inodecache();
602 }
604 module_init(init_qnx4_fs)
605 module_exit(exit_qnx4_fs)
606 MODULE_LICENSE("GPL");