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mac80211: 802.11w - Optional software CCMP for management frames
[linux-2.6/linux-2.6-openrd.git] / fs / fuse / inode.c
blob459b73dd45e1302298ab75a5e6c4bee86849ebae
1 /*
2 FUSE: Filesystem in Userspace
3 Copyright (C) 2001-2008 Miklos Szeredi <miklos@szeredi.hu>
4
5 This program can be distributed under the terms of the GNU GPL.
6 See the file COPYING.
7 */
8
9 #include "fuse_i.h"
10
11 #include <linux/pagemap.h>
12 #include <linux/slab.h>
13 #include <linux/file.h>
14 #include <linux/seq_file.h>
15 #include <linux/init.h>
16 #include <linux/module.h>
17 #include <linux/parser.h>
18 #include <linux/statfs.h>
19 #include <linux/random.h>
20 #include <linux/sched.h>
21 #include <linux/exportfs.h>
22
23 MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>");
24 MODULE_DESCRIPTION("Filesystem in Userspace");
25 MODULE_LICENSE("GPL");
26
27 static struct kmem_cache *fuse_inode_cachep;
28 struct list_head fuse_conn_list;
29 DEFINE_MUTEX(fuse_mutex);
30
31 #define FUSE_SUPER_MAGIC 0x65735546
32
33 #define FUSE_DEFAULT_BLKSIZE 512
34
35 struct fuse_mount_data {
36 int fd;
37 unsigned rootmode;
38 unsigned user_id;
39 unsigned group_id;
40 unsigned fd_present:1;
41 unsigned rootmode_present:1;
42 unsigned user_id_present:1;
43 unsigned group_id_present:1;
44 unsigned flags;
45 unsigned max_read;
46 unsigned blksize;
47 };
48
49 static struct inode *fuse_alloc_inode(struct super_block *sb)
50 {
51 struct inode *inode;
52 struct fuse_inode *fi;
53
54 inode = kmem_cache_alloc(fuse_inode_cachep, GFP_KERNEL);
55 if (!inode)
56 return NULL;
57
58 fi = get_fuse_inode(inode);
59 fi->i_time = 0;
60 fi->nodeid = 0;
61 fi->nlookup = 0;
62 fi->attr_version = 0;
63 fi->writectr = 0;
64 INIT_LIST_HEAD(&fi->write_files);
65 INIT_LIST_HEAD(&fi->queued_writes);
66 INIT_LIST_HEAD(&fi->writepages);
67 init_waitqueue_head(&fi->page_waitq);
68 fi->forget_req = fuse_request_alloc();
69 if (!fi->forget_req) {
70 kmem_cache_free(fuse_inode_cachep, inode);
71 return NULL;
72 }
73
74 return inode;
75 }
76
77 static void fuse_destroy_inode(struct inode *inode)
78 {
79 struct fuse_inode *fi = get_fuse_inode(inode);
80 BUG_ON(!list_empty(&fi->write_files));
81 BUG_ON(!list_empty(&fi->queued_writes));
82 if (fi->forget_req)
83 fuse_request_free(fi->forget_req);
84 kmem_cache_free(fuse_inode_cachep, inode);
85 }
86
87 void fuse_send_forget(struct fuse_conn *fc, struct fuse_req *req,
88 u64 nodeid, u64 nlookup)
89 {
90 struct fuse_forget_in *inarg = &req->misc.forget_in;
91 inarg->nlookup = nlookup;
92 req->in.h.opcode = FUSE_FORGET;
93 req->in.h.nodeid = nodeid;
94 req->in.numargs = 1;
95 req->in.args[0].size = sizeof(struct fuse_forget_in);
96 req->in.args[0].value = inarg;
97 fuse_request_send_noreply(fc, req);
98 }
99
100 static void fuse_clear_inode(struct inode *inode)
101 {
102 if (inode->i_sb->s_flags & MS_ACTIVE) {
103 struct fuse_conn *fc = get_fuse_conn(inode);
104 struct fuse_inode *fi = get_fuse_inode(inode);
105 fuse_send_forget(fc, fi->forget_req, fi->nodeid, fi->nlookup);
106 fi->forget_req = NULL;
107 }
108 }
109
110 static int fuse_remount_fs(struct super_block *sb, int *flags, char *data)
111 {
112 if (*flags & MS_MANDLOCK)
113 return -EINVAL;
114
115 return 0;
116 }
117
118 void fuse_truncate(struct address_space *mapping, loff_t offset)
119 {
120 /* See vmtruncate() */
121 unmap_mapping_range(mapping, offset + PAGE_SIZE - 1, 0, 1);
122 truncate_inode_pages(mapping, offset);
123 unmap_mapping_range(mapping, offset + PAGE_SIZE - 1, 0, 1);
124 }
125
126 void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr,
127 u64 attr_valid)
128 {
129 struct fuse_conn *fc = get_fuse_conn(inode);
130 struct fuse_inode *fi = get_fuse_inode(inode);
131
132 fi->attr_version = ++fc->attr_version;
133 fi->i_time = attr_valid;
134
135 inode->i_ino = attr->ino;
136 inode->i_mode = (inode->i_mode & S_IFMT) | (attr->mode & 07777);
137 inode->i_nlink = attr->nlink;
138 inode->i_uid = attr->uid;
139 inode->i_gid = attr->gid;
140 inode->i_blocks = attr->blocks;
141 inode->i_atime.tv_sec = attr->atime;
142 inode->i_atime.tv_nsec = attr->atimensec;
143 inode->i_mtime.tv_sec = attr->mtime;
144 inode->i_mtime.tv_nsec = attr->mtimensec;
145 inode->i_ctime.tv_sec = attr->ctime;
146 inode->i_ctime.tv_nsec = attr->ctimensec;
147
148 if (attr->blksize != 0)
149 inode->i_blkbits = ilog2(attr->blksize);
150 else
151 inode->i_blkbits = inode->i_sb->s_blocksize_bits;
152
153 /*
154 * Don't set the sticky bit in i_mode, unless we want the VFS
155 * to check permissions. This prevents failures due to the
156 * check in may_delete().
157 */
158 fi->orig_i_mode = inode->i_mode;
159 if (!(fc->flags & FUSE_DEFAULT_PERMISSIONS))
160 inode->i_mode &= ~S_ISVTX;
161 }
162
163 void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
164 u64 attr_valid, u64 attr_version)
165 {
166 struct fuse_conn *fc = get_fuse_conn(inode);
167 struct fuse_inode *fi = get_fuse_inode(inode);
168 loff_t oldsize;
169
170 spin_lock(&fc->lock);
171 if (attr_version != 0 && fi->attr_version > attr_version) {
172 spin_unlock(&fc->lock);
173 return;
174 }
175
176 fuse_change_attributes_common(inode, attr, attr_valid);
177
178 oldsize = inode->i_size;
179 i_size_write(inode, attr->size);
180 spin_unlock(&fc->lock);
181
182 if (S_ISREG(inode->i_mode) && oldsize != attr->size) {
183 if (attr->size < oldsize)
184 fuse_truncate(inode->i_mapping, attr->size);
185 invalidate_inode_pages2(inode->i_mapping);
186 }
187 }
188
189 static void fuse_init_inode(struct inode *inode, struct fuse_attr *attr)
190 {
191 inode->i_mode = attr->mode & S_IFMT;
192 inode->i_size = attr->size;
193 if (S_ISREG(inode->i_mode)) {
194 fuse_init_common(inode);
195 fuse_init_file_inode(inode);
196 } else if (S_ISDIR(inode->i_mode))
197 fuse_init_dir(inode);
198 else if (S_ISLNK(inode->i_mode))
199 fuse_init_symlink(inode);
200 else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
201 S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
202 fuse_init_common(inode);
203 init_special_inode(inode, inode->i_mode,
204 new_decode_dev(attr->rdev));
205 } else
206 BUG();
207 }
208
209 static int fuse_inode_eq(struct inode *inode, void *_nodeidp)
210 {
211 u64 nodeid = *(u64 *) _nodeidp;
212 if (get_node_id(inode) == nodeid)
213 return 1;
214 else
215 return 0;
216 }
217
218 static int fuse_inode_set(struct inode *inode, void *_nodeidp)
219 {
220 u64 nodeid = *(u64 *) _nodeidp;
221 get_fuse_inode(inode)->nodeid = nodeid;
222 return 0;
223 }
224
225 struct inode *fuse_iget(struct super_block *sb, u64 nodeid,
226 int generation, struct fuse_attr *attr,
227 u64 attr_valid, u64 attr_version)
228 {
229 struct inode *inode;
230 struct fuse_inode *fi;
231 struct fuse_conn *fc = get_fuse_conn_super(sb);
232
233 retry:
234 inode = iget5_locked(sb, nodeid, fuse_inode_eq, fuse_inode_set, &nodeid);
235 if (!inode)
236 return NULL;
237
238 if ((inode->i_state & I_NEW)) {
239 inode->i_flags |= S_NOATIME|S_NOCMTIME;
240 inode->i_generation = generation;
241 inode->i_data.backing_dev_info = &fc->bdi;
242 fuse_init_inode(inode, attr);
243 unlock_new_inode(inode);
244 } else if ((inode->i_mode ^ attr->mode) & S_IFMT) {
245 /* Inode has changed type, any I/O on the old should fail */
246 make_bad_inode(inode);
247 iput(inode);
248 goto retry;
249 }
250
251 fi = get_fuse_inode(inode);
252 spin_lock(&fc->lock);
253 fi->nlookup++;
254 spin_unlock(&fc->lock);
255 fuse_change_attributes(inode, attr, attr_valid, attr_version);
256
257 return inode;
258 }
259
260 static void fuse_umount_begin(struct super_block *sb)
261 {
262 fuse_abort_conn(get_fuse_conn_super(sb));
263 }
264
265 static void fuse_send_destroy(struct fuse_conn *fc)
266 {
267 struct fuse_req *req = fc->destroy_req;
268 if (req && fc->conn_init) {
269 fc->destroy_req = NULL;
270 req->in.h.opcode = FUSE_DESTROY;
271 req->force = 1;
272 fuse_request_send(fc, req);
273 fuse_put_request(fc, req);
274 }
275 }
276
277 static void fuse_put_super(struct super_block *sb)
278 {
279 struct fuse_conn *fc = get_fuse_conn_super(sb);
280
281 fuse_send_destroy(fc);
282 spin_lock(&fc->lock);
283 fc->connected = 0;
284 fc->blocked = 0;
285 spin_unlock(&fc->lock);
286 /* Flush all readers on this fs */
287 kill_fasync(&fc->fasync, SIGIO, POLL_IN);
288 wake_up_all(&fc->waitq);
289 wake_up_all(&fc->blocked_waitq);
290 wake_up_all(&fc->reserved_req_waitq);
291 mutex_lock(&fuse_mutex);
292 list_del(&fc->entry);
293 fuse_ctl_remove_conn(fc);
294 mutex_unlock(&fuse_mutex);
295 bdi_destroy(&fc->bdi);
296 fuse_conn_put(fc);
297 }
298
299 static void convert_fuse_statfs(struct kstatfs *stbuf, struct fuse_kstatfs *attr)
300 {
301 stbuf->f_type = FUSE_SUPER_MAGIC;
302 stbuf->f_bsize = attr->bsize;
303 stbuf->f_frsize = attr->frsize;
304 stbuf->f_blocks = attr->blocks;
305 stbuf->f_bfree = attr->bfree;
306 stbuf->f_bavail = attr->bavail;
307 stbuf->f_files = attr->files;
308 stbuf->f_ffree = attr->ffree;
309 stbuf->f_namelen = attr->namelen;
310 /* fsid is left zero */
311 }
312
313 static int fuse_statfs(struct dentry *dentry, struct kstatfs *buf)
314 {
315 struct super_block *sb = dentry->d_sb;
316 struct fuse_conn *fc = get_fuse_conn_super(sb);
317 struct fuse_req *req;
318 struct fuse_statfs_out outarg;
319 int err;
320
321 if (!fuse_allow_task(fc, current)) {
322 buf->f_type = FUSE_SUPER_MAGIC;
323 return 0;
324 }
325
326 req = fuse_get_req(fc);
327 if (IS_ERR(req))
328 return PTR_ERR(req);
329
330 memset(&outarg, 0, sizeof(outarg));
331 req->in.numargs = 0;
332 req->in.h.opcode = FUSE_STATFS;
333 req->in.h.nodeid = get_node_id(dentry->d_inode);
334 req->out.numargs = 1;
335 req->out.args[0].size =
336 fc->minor < 4 ? FUSE_COMPAT_STATFS_SIZE : sizeof(outarg);
337 req->out.args[0].value = &outarg;
338 fuse_request_send(fc, req);
339 err = req->out.h.error;
340 if (!err)
341 convert_fuse_statfs(buf, &outarg.st);
342 fuse_put_request(fc, req);
343 return err;
344 }
345
346 enum {
347 OPT_FD,
348 OPT_ROOTMODE,
349 OPT_USER_ID,
350 OPT_GROUP_ID,
351 OPT_DEFAULT_PERMISSIONS,
352 OPT_ALLOW_OTHER,
353 OPT_MAX_READ,
354 OPT_BLKSIZE,
355 OPT_ERR
356 };
357
358 static const match_table_t tokens = {
359 {OPT_FD, "fd=%u"},
360 {OPT_ROOTMODE, "rootmode=%o"},
361 {OPT_USER_ID, "user_id=%u"},
362 {OPT_GROUP_ID, "group_id=%u"},
363 {OPT_DEFAULT_PERMISSIONS, "default_permissions"},
364 {OPT_ALLOW_OTHER, "allow_other"},
365 {OPT_MAX_READ, "max_read=%u"},
366 {OPT_BLKSIZE, "blksize=%u"},
367 {OPT_ERR, NULL}
368 };
369
370 static int parse_fuse_opt(char *opt, struct fuse_mount_data *d, int is_bdev)
371 {
372 char *p;
373 memset(d, 0, sizeof(struct fuse_mount_data));
374 d->max_read = ~0;
375 d->blksize = FUSE_DEFAULT_BLKSIZE;
376
377 while ((p = strsep(&opt, ",")) != NULL) {
378 int token;
379 int value;
380 substring_t args[MAX_OPT_ARGS];
381 if (!*p)
382 continue;
383
384 token = match_token(p, tokens, args);
385 switch (token) {
386 case OPT_FD:
387 if (match_int(&args[0], &value))
388 return 0;
389 d->fd = value;
390 d->fd_present = 1;
391 break;
392
393 case OPT_ROOTMODE:
394 if (match_octal(&args[0], &value))
395 return 0;
396 if (!fuse_valid_type(value))
397 return 0;
398 d->rootmode = value;
399 d->rootmode_present = 1;
400 break;
401
402 case OPT_USER_ID:
403 if (match_int(&args[0], &value))
404 return 0;
405 d->user_id = value;
406 d->user_id_present = 1;
407 break;
408
409 case OPT_GROUP_ID:
410 if (match_int(&args[0], &value))
411 return 0;
412 d->group_id = value;
413 d->group_id_present = 1;
414 break;
415
416 case OPT_DEFAULT_PERMISSIONS:
417 d->flags |= FUSE_DEFAULT_PERMISSIONS;
418 break;
419
420 case OPT_ALLOW_OTHER:
421 d->flags |= FUSE_ALLOW_OTHER;
422 break;
423
424 case OPT_MAX_READ:
425 if (match_int(&args[0], &value))
426 return 0;
427 d->max_read = value;
428 break;
429
430 case OPT_BLKSIZE:
431 if (!is_bdev || match_int(&args[0], &value))
432 return 0;
433 d->blksize = value;
434 break;
435
436 default:
437 return 0;
438 }
439 }
440
441 if (!d->fd_present || !d->rootmode_present ||
442 !d->user_id_present || !d->group_id_present)
443 return 0;
444
445 return 1;
446 }
447
448 static int fuse_show_options(struct seq_file *m, struct vfsmount *mnt)
449 {
450 struct fuse_conn *fc = get_fuse_conn_super(mnt->mnt_sb);
451
452 seq_printf(m, ",user_id=%u", fc->user_id);
453 seq_printf(m, ",group_id=%u", fc->group_id);
454 if (fc->flags & FUSE_DEFAULT_PERMISSIONS)
455 seq_puts(m, ",default_permissions");
456 if (fc->flags & FUSE_ALLOW_OTHER)
457 seq_puts(m, ",allow_other");
458 if (fc->max_read != ~0)
459 seq_printf(m, ",max_read=%u", fc->max_read);
460 if (mnt->mnt_sb->s_bdev &&
461 mnt->mnt_sb->s_blocksize != FUSE_DEFAULT_BLKSIZE)
462 seq_printf(m, ",blksize=%lu", mnt->mnt_sb->s_blocksize);
463 return 0;
464 }
465
466 int fuse_conn_init(struct fuse_conn *fc, struct super_block *sb)
467 {
468 int err;
469
470 memset(fc, 0, sizeof(*fc));
471 spin_lock_init(&fc->lock);
472 mutex_init(&fc->inst_mutex);
473 atomic_set(&fc->count, 1);
474 init_waitqueue_head(&fc->waitq);
475 init_waitqueue_head(&fc->blocked_waitq);
476 init_waitqueue_head(&fc->reserved_req_waitq);
477 INIT_LIST_HEAD(&fc->pending);
478 INIT_LIST_HEAD(&fc->processing);
479 INIT_LIST_HEAD(&fc->io);
480 INIT_LIST_HEAD(&fc->interrupts);
481 INIT_LIST_HEAD(&fc->bg_queue);
482 INIT_LIST_HEAD(&fc->entry);
483 atomic_set(&fc->num_waiting, 0);
484 fc->bdi.ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE;
485 fc->bdi.unplug_io_fn = default_unplug_io_fn;
486 /* fuse does it's own writeback accounting */
487 fc->bdi.capabilities = BDI_CAP_NO_ACCT_WB;
488 fc->khctr = 0;
489 fc->polled_files = RB_ROOT;
490 fc->dev = sb->s_dev;
491 err = bdi_init(&fc->bdi);
492 if (err)
493 goto error_mutex_destroy;
494 if (sb->s_bdev) {
495 err = bdi_register(&fc->bdi, NULL, "%u:%u-fuseblk",
496 MAJOR(fc->dev), MINOR(fc->dev));
497 } else {
498 err = bdi_register_dev(&fc->bdi, fc->dev);
499 }
500 if (err)
501 goto error_bdi_destroy;
502 /*
503 * For a single fuse filesystem use max 1% of dirty +
504 * writeback threshold.
505 *
506 * This gives about 1M of write buffer for memory maps on a
507 * machine with 1G and 10% dirty_ratio, which should be more
508 * than enough.
509 *
510 * Privileged users can raise it by writing to
511 *
512 * /sys/class/bdi/<bdi>/max_ratio
513 */
514 bdi_set_max_ratio(&fc->bdi, 1);
515 fc->reqctr = 0;
516 fc->blocked = 1;
517 fc->attr_version = 1;
518 get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key));
519
520 return 0;
521
522 error_bdi_destroy:
523 bdi_destroy(&fc->bdi);
524 error_mutex_destroy:
525 mutex_destroy(&fc->inst_mutex);
526 return err;
527 }
528 EXPORT_SYMBOL_GPL(fuse_conn_init);
529
530 void fuse_conn_put(struct fuse_conn *fc)
531 {
532 if (atomic_dec_and_test(&fc->count)) {
533 if (fc->destroy_req)
534 fuse_request_free(fc->destroy_req);
535 mutex_destroy(&fc->inst_mutex);
536 fc->release(fc);
537 }
538 }
539
540 struct fuse_conn *fuse_conn_get(struct fuse_conn *fc)
541 {
542 atomic_inc(&fc->count);
543 return fc;
544 }
545
546 static struct inode *fuse_get_root_inode(struct super_block *sb, unsigned mode)
547 {
548 struct fuse_attr attr;
549 memset(&attr, 0, sizeof(attr));
550
551 attr.mode = mode;
552 attr.ino = FUSE_ROOT_ID;
553 attr.nlink = 1;
554 return fuse_iget(sb, 1, 0, &attr, 0, 0);
555 }
556
557 struct fuse_inode_handle {
558 u64 nodeid;
559 u32 generation;
560 };
561
562 static struct dentry *fuse_get_dentry(struct super_block *sb,
563 struct fuse_inode_handle *handle)
564 {
565 struct fuse_conn *fc = get_fuse_conn_super(sb);
566 struct inode *inode;
567 struct dentry *entry;
568 int err = -ESTALE;
569
570 if (handle->nodeid == 0)
571 goto out_err;
572
573 inode = ilookup5(sb, handle->nodeid, fuse_inode_eq, &handle->nodeid);
574 if (!inode) {
575 struct fuse_entry_out outarg;
576 struct qstr name;
577
578 if (!fc->export_support)
579 goto out_err;
580
581 name.len = 1;
582 name.name = ".";
583 err = fuse_lookup_name(sb, handle->nodeid, &name, &outarg,
584 &inode);
585 if (err && err != -ENOENT)
586 goto out_err;
587 if (err || !inode) {
588 err = -ESTALE;
589 goto out_err;
590 }
591 err = -EIO;
592 if (get_node_id(inode) != handle->nodeid)
593 goto out_iput;
594 }
595 err = -ESTALE;
596 if (inode->i_generation != handle->generation)
597 goto out_iput;
598
599 entry = d_obtain_alias(inode);
600 if (!IS_ERR(entry) && get_node_id(inode) != FUSE_ROOT_ID) {
601 entry->d_op = &fuse_dentry_operations;
602 fuse_invalidate_entry_cache(entry);
603 }
604
605 return entry;
606
607 out_iput:
608 iput(inode);
609 out_err:
610 return ERR_PTR(err);
611 }
612
613 static int fuse_encode_fh(struct dentry *dentry, u32 *fh, int *max_len,
614 int connectable)
615 {
616 struct inode *inode = dentry->d_inode;
617 bool encode_parent = connectable && !S_ISDIR(inode->i_mode);
618 int len = encode_parent ? 6 : 3;
619 u64 nodeid;
620 u32 generation;
621
622 if (*max_len < len)
623 return 255;
624
625 nodeid = get_fuse_inode(inode)->nodeid;
626 generation = inode->i_generation;
627
628 fh[0] = (u32)(nodeid >> 32);
629 fh[1] = (u32)(nodeid & 0xffffffff);
630 fh[2] = generation;
631
632 if (encode_parent) {
633 struct inode *parent;
634
635 spin_lock(&dentry->d_lock);
636 parent = dentry->d_parent->d_inode;
637 nodeid = get_fuse_inode(parent)->nodeid;
638 generation = parent->i_generation;
639 spin_unlock(&dentry->d_lock);
640
641 fh[3] = (u32)(nodeid >> 32);
642 fh[4] = (u32)(nodeid & 0xffffffff);
643 fh[5] = generation;
644 }
645
646 *max_len = len;
647 return encode_parent ? 0x82 : 0x81;
648 }
649
650 static struct dentry *fuse_fh_to_dentry(struct super_block *sb,
651 struct fid *fid, int fh_len, int fh_type)
652 {
653 struct fuse_inode_handle handle;
654
655 if ((fh_type != 0x81 && fh_type != 0x82) || fh_len < 3)
656 return NULL;
657
658 handle.nodeid = (u64) fid->raw[0] << 32;
659 handle.nodeid |= (u64) fid->raw[1];
660 handle.generation = fid->raw[2];
661 return fuse_get_dentry(sb, &handle);
662 }
663
664 static struct dentry *fuse_fh_to_parent(struct super_block *sb,
665 struct fid *fid, int fh_len, int fh_type)
666 {
667 struct fuse_inode_handle parent;
668
669 if (fh_type != 0x82 || fh_len < 6)
670 return NULL;
671
672 parent.nodeid = (u64) fid->raw[3] << 32;
673 parent.nodeid |= (u64) fid->raw[4];
674 parent.generation = fid->raw[5];
675 return fuse_get_dentry(sb, &parent);
676 }
677
678 static struct dentry *fuse_get_parent(struct dentry *child)
679 {
680 struct inode *child_inode = child->d_inode;
681 struct fuse_conn *fc = get_fuse_conn(child_inode);
682 struct inode *inode;
683 struct dentry *parent;
684 struct fuse_entry_out outarg;
685 struct qstr name;
686 int err;
687
688 if (!fc->export_support)
689 return ERR_PTR(-ESTALE);
690
691 name.len = 2;
692 name.name = "..";
693 err = fuse_lookup_name(child_inode->i_sb, get_node_id(child_inode),
694 &name, &outarg, &inode);
695 if (err) {
696 if (err == -ENOENT)
697 return ERR_PTR(-ESTALE);
698 return ERR_PTR(err);
699 }
700
701 parent = d_obtain_alias(inode);
702 if (!IS_ERR(parent) && get_node_id(inode) != FUSE_ROOT_ID) {
703 parent->d_op = &fuse_dentry_operations;
704 fuse_invalidate_entry_cache(parent);
705 }
706
707 return parent;
708 }
709
710 static const struct export_operations fuse_export_operations = {
711 .fh_to_dentry = fuse_fh_to_dentry,
712 .fh_to_parent = fuse_fh_to_parent,
713 .encode_fh = fuse_encode_fh,
714 .get_parent = fuse_get_parent,
715 };
716
717 static const struct super_operations fuse_super_operations = {
718 .alloc_inode = fuse_alloc_inode,
719 .destroy_inode = fuse_destroy_inode,
720 .clear_inode = fuse_clear_inode,
721 .drop_inode = generic_delete_inode,
722 .remount_fs = fuse_remount_fs,
723 .put_super = fuse_put_super,
724 .umount_begin = fuse_umount_begin,
725 .statfs = fuse_statfs,
726 .show_options = fuse_show_options,
727 };
728
729 static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req)
730 {
731 struct fuse_init_out *arg = &req->misc.init_out;
732
733 if (req->out.h.error || arg->major != FUSE_KERNEL_VERSION)
734 fc->conn_error = 1;
735 else {
736 unsigned long ra_pages;
737
738 if (arg->minor >= 6) {
739 ra_pages = arg->max_readahead / PAGE_CACHE_SIZE;
740 if (arg->flags & FUSE_ASYNC_READ)
741 fc->async_read = 1;
742 if (!(arg->flags & FUSE_POSIX_LOCKS))
743 fc->no_lock = 1;
744 if (arg->flags & FUSE_ATOMIC_O_TRUNC)
745 fc->atomic_o_trunc = 1;
746 if (arg->minor >= 9) {
747 /* LOOKUP has dependency on proto version */
748 if (arg->flags & FUSE_EXPORT_SUPPORT)
749 fc->export_support = 1;
750 }
751 if (arg->flags & FUSE_BIG_WRITES)
752 fc->big_writes = 1;
753 } else {
754 ra_pages = fc->max_read / PAGE_CACHE_SIZE;
755 fc->no_lock = 1;
756 }
757
758 fc->bdi.ra_pages = min(fc->bdi.ra_pages, ra_pages);
759 fc->minor = arg->minor;
760 fc->max_write = arg->minor < 5 ? 4096 : arg->max_write;
761 fc->max_write = max_t(unsigned, 4096, fc->max_write);
762 fc->conn_init = 1;
763 }
764 fc->blocked = 0;
765 wake_up_all(&fc->blocked_waitq);
766 }
767
768 static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req)
769 {
770 struct fuse_init_in *arg = &req->misc.init_in;
771
772 arg->major = FUSE_KERNEL_VERSION;
773 arg->minor = FUSE_KERNEL_MINOR_VERSION;
774 arg->max_readahead = fc->bdi.ra_pages * PAGE_CACHE_SIZE;
775 arg->flags |= FUSE_ASYNC_READ | FUSE_POSIX_LOCKS | FUSE_ATOMIC_O_TRUNC |
776 FUSE_EXPORT_SUPPORT | FUSE_BIG_WRITES;
777 req->in.h.opcode = FUSE_INIT;
778 req->in.numargs = 1;
779 req->in.args[0].size = sizeof(*arg);
780 req->in.args[0].value = arg;
781 req->out.numargs = 1;
782 /* Variable length arguement used for backward compatibility
783 with interface version < 7.5. Rest of init_out is zeroed
784 by do_get_request(), so a short reply is not a problem */
785 req->out.argvar = 1;
786 req->out.args[0].size = sizeof(struct fuse_init_out);
787 req->out.args[0].value = &req->misc.init_out;
788 req->end = process_init_reply;
789 fuse_request_send_background(fc, req);
790 }
791
792 static void fuse_free_conn(struct fuse_conn *fc)
793 {
794 kfree(fc);
795 }
796
797 static int fuse_fill_super(struct super_block *sb, void *data, int silent)
798 {
799 struct fuse_conn *fc;
800 struct inode *root;
801 struct fuse_mount_data d;
802 struct file *file;
803 struct dentry *root_dentry;
804 struct fuse_req *init_req;
805 int err;
806 int is_bdev = sb->s_bdev != NULL;
807
808 err = -EINVAL;
809 if (sb->s_flags & MS_MANDLOCK)
810 goto err;
811
812 if (!parse_fuse_opt((char *) data, &d, is_bdev))
813 goto err;
814
815 if (is_bdev) {
816 #ifdef CONFIG_BLOCK
817 err = -EINVAL;
818 if (!sb_set_blocksize(sb, d.blksize))
819 goto err;
820 #endif
821 } else {
822 sb->s_blocksize = PAGE_CACHE_SIZE;
823 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
824 }
825 sb->s_magic = FUSE_SUPER_MAGIC;
826 sb->s_op = &fuse_super_operations;
827 sb->s_maxbytes = MAX_LFS_FILESIZE;
828 sb->s_export_op = &fuse_export_operations;
829
830 file = fget(d.fd);
831 err = -EINVAL;
832 if (!file)
833 goto err;
834
835 if (file->f_op != &fuse_dev_operations)
836 goto err_fput;
837
838 fc = kmalloc(sizeof(*fc), GFP_KERNEL);
839 err = -ENOMEM;
840 if (!fc)
841 goto err_fput;
842
843 err = fuse_conn_init(fc, sb);
844 if (err) {
845 kfree(fc);
846 goto err_fput;
847 }
848
849 fc->release = fuse_free_conn;
850 fc->flags = d.flags;
851 fc->user_id = d.user_id;
852 fc->group_id = d.group_id;
853 fc->max_read = max_t(unsigned, 4096, d.max_read);
854
855 /* Used by get_root_inode() */
856 sb->s_fs_info = fc;
857
858 err = -ENOMEM;
859 root = fuse_get_root_inode(sb, d.rootmode);
860 if (!root)
861 goto err_put_conn;
862
863 root_dentry = d_alloc_root(root);
864 if (!root_dentry) {
865 iput(root);
866 goto err_put_conn;
867 }
868
869 init_req = fuse_request_alloc();
870 if (!init_req)
871 goto err_put_root;
872
873 if (is_bdev) {
874 fc->destroy_req = fuse_request_alloc();
875 if (!fc->destroy_req)
876 goto err_free_init_req;
877 }
878
879 mutex_lock(&fuse_mutex);
880 err = -EINVAL;
881 if (file->private_data)
882 goto err_unlock;
883
884 err = fuse_ctl_add_conn(fc);
885 if (err)
886 goto err_unlock;
887
888 list_add_tail(&fc->entry, &fuse_conn_list);
889 sb->s_root = root_dentry;
890 fc->connected = 1;
891 file->private_data = fuse_conn_get(fc);
892 mutex_unlock(&fuse_mutex);
893 /*
894 * atomic_dec_and_test() in fput() provides the necessary
895 * memory barrier for file->private_data to be visible on all
896 * CPUs after this
897 */
898 fput(file);
899
900 fuse_send_init(fc, init_req);
901
902 return 0;
903
904 err_unlock:
905 mutex_unlock(&fuse_mutex);
906 err_free_init_req:
907 fuse_request_free(init_req);
908 err_put_root:
909 dput(root_dentry);
910 err_put_conn:
911 fuse_conn_put(fc);
912 err_fput:
913 fput(file);
914 err:
915 return err;
916 }
917
918 static int fuse_get_sb(struct file_system_type *fs_type,
919 int flags, const char *dev_name,
920 void *raw_data, struct vfsmount *mnt)
921 {
922 return get_sb_nodev(fs_type, flags, raw_data, fuse_fill_super, mnt);
923 }
924
925 static struct file_system_type fuse_fs_type = {
926 .owner = THIS_MODULE,
927 .name = "fuse",
928 .fs_flags = FS_HAS_SUBTYPE,
929 .get_sb = fuse_get_sb,
930 .kill_sb = kill_anon_super,
931 };
932
933 #ifdef CONFIG_BLOCK
934 static int fuse_get_sb_blk(struct file_system_type *fs_type,
935 int flags, const char *dev_name,
936 void *raw_data, struct vfsmount *mnt)
937 {
938 return get_sb_bdev(fs_type, flags, dev_name, raw_data, fuse_fill_super,
939 mnt);
940 }
941
942 static struct file_system_type fuseblk_fs_type = {
943 .owner = THIS_MODULE,
944 .name = "fuseblk",
945 .get_sb = fuse_get_sb_blk,
946 .kill_sb = kill_block_super,
947 .fs_flags = FS_REQUIRES_DEV | FS_HAS_SUBTYPE,
948 };
949
950 static inline int register_fuseblk(void)
951 {
952 return register_filesystem(&fuseblk_fs_type);
953 }
954
955 static inline void unregister_fuseblk(void)
956 {
957 unregister_filesystem(&fuseblk_fs_type);
958 }
959 #else
960 static inline int register_fuseblk(void)
961 {
962 return 0;
963 }
964
965 static inline void unregister_fuseblk(void)
966 {
967 }
968 #endif
969
970 static void fuse_inode_init_once(void *foo)
971 {
972 struct inode *inode = foo;
973
974 inode_init_once(inode);
975 }
976
977 static int __init fuse_fs_init(void)
978 {
979 int err;
980
981 err = register_filesystem(&fuse_fs_type);
982 if (err)
983 goto out;
984
985 err = register_fuseblk();
986 if (err)
987 goto out_unreg;
988
989 fuse_inode_cachep = kmem_cache_create("fuse_inode",
990 sizeof(struct fuse_inode),
991 0, SLAB_HWCACHE_ALIGN,
992 fuse_inode_init_once);
993 err = -ENOMEM;
994 if (!fuse_inode_cachep)
995 goto out_unreg2;
996
997 return 0;
998
999 out_unreg2:
1000 unregister_fuseblk();
1001 out_unreg:
1002 unregister_filesystem(&fuse_fs_type);
1003 out:
1004 return err;
1005 }
1006
1007 static void fuse_fs_cleanup(void)
1008 {
1009 unregister_filesystem(&fuse_fs_type);
1010 unregister_fuseblk();
1011 kmem_cache_destroy(fuse_inode_cachep);
1012 }
1013
1014 static struct kobject *fuse_kobj;
1015 static struct kobject *connections_kobj;
1016
1017 static int fuse_sysfs_init(void)
1018 {
1019 int err;
1020
1021 fuse_kobj = kobject_create_and_add("fuse", fs_kobj);
1022 if (!fuse_kobj) {
1023 err = -ENOMEM;
1024 goto out_err;
1025 }
1026
1027 connections_kobj = kobject_create_and_add("connections", fuse_kobj);
1028 if (!connections_kobj) {
1029 err = -ENOMEM;
1030 goto out_fuse_unregister;
1031 }
1032
1033 return 0;
1034
1035 out_fuse_unregister:
1036 kobject_put(fuse_kobj);
1037 out_err:
1038 return err;
1039 }
1040
1041 static void fuse_sysfs_cleanup(void)
1042 {
1043 kobject_put(connections_kobj);
1044 kobject_put(fuse_kobj);
1045 }
1046
1047 static int __init fuse_init(void)
1048 {
1049 int res;
1050
1051 printk(KERN_INFO "fuse init (API version %i.%i)\n",
1052 FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION);
1053
1054 INIT_LIST_HEAD(&fuse_conn_list);
1055 res = fuse_fs_init();
1056 if (res)
1057 goto err;
1058
1059 res = fuse_dev_init();
1060 if (res)
1061 goto err_fs_cleanup;
1062
1063 res = fuse_sysfs_init();
1064 if (res)
1065 goto err_dev_cleanup;
1066
1067 res = fuse_ctl_init();
1068 if (res)
1069 goto err_sysfs_cleanup;
1070
1071 return 0;
1072
1073 err_sysfs_cleanup:
1074 fuse_sysfs_cleanup();
1075 err_dev_cleanup:
1076 fuse_dev_cleanup();
1077 err_fs_cleanup:
1078 fuse_fs_cleanup();
1079 err:
1080 return res;
1081 }
1082
1083 static void __exit fuse_exit(void)
1084 {
1085 printk(KERN_DEBUG "fuse exit\n");
1086
1087 fuse_ctl_cleanup();
1088 fuse_sysfs_cleanup();
1089 fuse_fs_cleanup();
1090 fuse_dev_cleanup();
1091 }
1092
1093 module_init(fuse_init);
1094 module_exit(fuse_exit);
linux 2.6 git repository for openrd