inode.c 19 KB

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  1. /*
  2. FUSE: Filesystem in Userspace
  3. Copyright (C) 2001-2006 Miklos Szeredi <miklos@szeredi.hu>
  4. This program can be distributed under the terms of the GNU GPL.
  5. See the file COPYING.
  6. */
  7. #include "fuse_i.h"
  8. #include <linux/pagemap.h>
  9. #include <linux/slab.h>
  10. #include <linux/file.h>
  11. #include <linux/seq_file.h>
  12. #include <linux/init.h>
  13. #include <linux/module.h>
  14. #include <linux/parser.h>
  15. #include <linux/statfs.h>
  16. #include <linux/random.h>
  17. #include <linux/sched.h>
  18. MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>");
  19. MODULE_DESCRIPTION("Filesystem in Userspace");
  20. MODULE_LICENSE("GPL");
  21. static struct kmem_cache *fuse_inode_cachep;
  22. struct list_head fuse_conn_list;
  23. DEFINE_MUTEX(fuse_mutex);
  24. #define FUSE_SUPER_MAGIC 0x65735546
  25. struct fuse_mount_data {
  26. int fd;
  27. unsigned rootmode;
  28. unsigned user_id;
  29. unsigned group_id;
  30. unsigned fd_present : 1;
  31. unsigned rootmode_present : 1;
  32. unsigned user_id_present : 1;
  33. unsigned group_id_present : 1;
  34. unsigned flags;
  35. unsigned max_read;
  36. unsigned blksize;
  37. };
  38. static struct inode *fuse_alloc_inode(struct super_block *sb)
  39. {
  40. struct inode *inode;
  41. struct fuse_inode *fi;
  42. inode = kmem_cache_alloc(fuse_inode_cachep, GFP_KERNEL);
  43. if (!inode)
  44. return NULL;
  45. fi = get_fuse_inode(inode);
  46. fi->i_time = 0;
  47. fi->nodeid = 0;
  48. fi->nlookup = 0;
  49. fi->forget_req = fuse_request_alloc();
  50. if (!fi->forget_req) {
  51. kmem_cache_free(fuse_inode_cachep, inode);
  52. return NULL;
  53. }
  54. return inode;
  55. }
  56. static void fuse_destroy_inode(struct inode *inode)
  57. {
  58. struct fuse_inode *fi = get_fuse_inode(inode);
  59. if (fi->forget_req)
  60. fuse_request_free(fi->forget_req);
  61. kmem_cache_free(fuse_inode_cachep, inode);
  62. }
  63. static void fuse_read_inode(struct inode *inode)
  64. {
  65. /* No op */
  66. }
  67. void fuse_send_forget(struct fuse_conn *fc, struct fuse_req *req,
  68. unsigned long nodeid, u64 nlookup)
  69. {
  70. struct fuse_forget_in *inarg = &req->misc.forget_in;
  71. inarg->nlookup = nlookup;
  72. req->in.h.opcode = FUSE_FORGET;
  73. req->in.h.nodeid = nodeid;
  74. req->in.numargs = 1;
  75. req->in.args[0].size = sizeof(struct fuse_forget_in);
  76. req->in.args[0].value = inarg;
  77. request_send_noreply(fc, req);
  78. }
  79. static void fuse_clear_inode(struct inode *inode)
  80. {
  81. if (inode->i_sb->s_flags & MS_ACTIVE) {
  82. struct fuse_conn *fc = get_fuse_conn(inode);
  83. struct fuse_inode *fi = get_fuse_inode(inode);
  84. fuse_send_forget(fc, fi->forget_req, fi->nodeid, fi->nlookup);
  85. fi->forget_req = NULL;
  86. }
  87. }
  88. static int fuse_remount_fs(struct super_block *sb, int *flags, char *data)
  89. {
  90. if (*flags & MS_MANDLOCK)
  91. return -EINVAL;
  92. return 0;
  93. }
  94. static void fuse_truncate(struct address_space *mapping, loff_t offset)
  95. {
  96. /* See vmtruncate() */
  97. unmap_mapping_range(mapping, offset + PAGE_SIZE - 1, 0, 1);
  98. truncate_inode_pages(mapping, offset);
  99. unmap_mapping_range(mapping, offset + PAGE_SIZE - 1, 0, 1);
  100. }
  101. void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr)
  102. {
  103. struct fuse_conn *fc = get_fuse_conn(inode);
  104. struct fuse_inode *fi = get_fuse_inode(inode);
  105. loff_t oldsize;
  106. inode->i_ino = attr->ino;
  107. inode->i_mode = (inode->i_mode & S_IFMT) | (attr->mode & 07777);
  108. inode->i_nlink = attr->nlink;
  109. inode->i_uid = attr->uid;
  110. inode->i_gid = attr->gid;
  111. inode->i_blocks = attr->blocks;
  112. inode->i_atime.tv_sec = attr->atime;
  113. inode->i_atime.tv_nsec = attr->atimensec;
  114. inode->i_mtime.tv_sec = attr->mtime;
  115. inode->i_mtime.tv_nsec = attr->mtimensec;
  116. inode->i_ctime.tv_sec = attr->ctime;
  117. inode->i_ctime.tv_nsec = attr->ctimensec;
  118. /*
  119. * Don't set the sticky bit in i_mode, unless we want the VFS
  120. * to check permissions. This prevents failures due to the
  121. * check in may_delete().
  122. */
  123. fi->orig_i_mode = inode->i_mode;
  124. if (!(fc->flags & FUSE_DEFAULT_PERMISSIONS))
  125. inode->i_mode &= ~S_ISVTX;
  126. spin_lock(&fc->lock);
  127. oldsize = inode->i_size;
  128. i_size_write(inode, attr->size);
  129. spin_unlock(&fc->lock);
  130. if (S_ISREG(inode->i_mode) && oldsize != attr->size) {
  131. if (attr->size < oldsize)
  132. fuse_truncate(inode->i_mapping, attr->size);
  133. invalidate_inode_pages2(inode->i_mapping);
  134. }
  135. }
  136. static void fuse_init_inode(struct inode *inode, struct fuse_attr *attr)
  137. {
  138. inode->i_mode = attr->mode & S_IFMT;
  139. inode->i_size = attr->size;
  140. if (S_ISREG(inode->i_mode)) {
  141. fuse_init_common(inode);
  142. fuse_init_file_inode(inode);
  143. } else if (S_ISDIR(inode->i_mode))
  144. fuse_init_dir(inode);
  145. else if (S_ISLNK(inode->i_mode))
  146. fuse_init_symlink(inode);
  147. else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
  148. S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
  149. fuse_init_common(inode);
  150. init_special_inode(inode, inode->i_mode,
  151. new_decode_dev(attr->rdev));
  152. } else
  153. BUG();
  154. }
  155. static int fuse_inode_eq(struct inode *inode, void *_nodeidp)
  156. {
  157. unsigned long nodeid = *(unsigned long *) _nodeidp;
  158. if (get_node_id(inode) == nodeid)
  159. return 1;
  160. else
  161. return 0;
  162. }
  163. static int fuse_inode_set(struct inode *inode, void *_nodeidp)
  164. {
  165. unsigned long nodeid = *(unsigned long *) _nodeidp;
  166. get_fuse_inode(inode)->nodeid = nodeid;
  167. return 0;
  168. }
  169. struct inode *fuse_iget(struct super_block *sb, unsigned long nodeid,
  170. int generation, struct fuse_attr *attr)
  171. {
  172. struct inode *inode;
  173. struct fuse_inode *fi;
  174. struct fuse_conn *fc = get_fuse_conn_super(sb);
  175. retry:
  176. inode = iget5_locked(sb, nodeid, fuse_inode_eq, fuse_inode_set, &nodeid);
  177. if (!inode)
  178. return NULL;
  179. if ((inode->i_state & I_NEW)) {
  180. inode->i_flags |= S_NOATIME|S_NOCMTIME;
  181. inode->i_generation = generation;
  182. inode->i_data.backing_dev_info = &fc->bdi;
  183. fuse_init_inode(inode, attr);
  184. unlock_new_inode(inode);
  185. } else if ((inode->i_mode ^ attr->mode) & S_IFMT) {
  186. /* Inode has changed type, any I/O on the old should fail */
  187. make_bad_inode(inode);
  188. iput(inode);
  189. goto retry;
  190. }
  191. fi = get_fuse_inode(inode);
  192. spin_lock(&fc->lock);
  193. fi->nlookup ++;
  194. spin_unlock(&fc->lock);
  195. fuse_change_attributes(inode, attr);
  196. return inode;
  197. }
  198. static void fuse_umount_begin(struct vfsmount *vfsmnt, int flags)
  199. {
  200. if (flags & MNT_FORCE)
  201. fuse_abort_conn(get_fuse_conn_super(vfsmnt->mnt_sb));
  202. }
  203. static void fuse_send_destroy(struct fuse_conn *fc)
  204. {
  205. struct fuse_req *req = fc->destroy_req;
  206. if (req && fc->conn_init) {
  207. fc->destroy_req = NULL;
  208. req->in.h.opcode = FUSE_DESTROY;
  209. req->force = 1;
  210. request_send(fc, req);
  211. fuse_put_request(fc, req);
  212. }
  213. }
  214. static void fuse_put_super(struct super_block *sb)
  215. {
  216. struct fuse_conn *fc = get_fuse_conn_super(sb);
  217. fuse_send_destroy(fc);
  218. spin_lock(&fc->lock);
  219. fc->connected = 0;
  220. fc->blocked = 0;
  221. spin_unlock(&fc->lock);
  222. /* Flush all readers on this fs */
  223. kill_fasync(&fc->fasync, SIGIO, POLL_IN);
  224. wake_up_all(&fc->waitq);
  225. wake_up_all(&fc->blocked_waitq);
  226. wake_up_all(&fc->reserved_req_waitq);
  227. mutex_lock(&fuse_mutex);
  228. list_del(&fc->entry);
  229. fuse_ctl_remove_conn(fc);
  230. mutex_unlock(&fuse_mutex);
  231. fuse_conn_put(fc);
  232. }
  233. static void convert_fuse_statfs(struct kstatfs *stbuf, struct fuse_kstatfs *attr)
  234. {
  235. stbuf->f_type = FUSE_SUPER_MAGIC;
  236. stbuf->f_bsize = attr->bsize;
  237. stbuf->f_frsize = attr->frsize;
  238. stbuf->f_blocks = attr->blocks;
  239. stbuf->f_bfree = attr->bfree;
  240. stbuf->f_bavail = attr->bavail;
  241. stbuf->f_files = attr->files;
  242. stbuf->f_ffree = attr->ffree;
  243. stbuf->f_namelen = attr->namelen;
  244. /* fsid is left zero */
  245. }
  246. static int fuse_statfs(struct dentry *dentry, struct kstatfs *buf)
  247. {
  248. struct super_block *sb = dentry->d_sb;
  249. struct fuse_conn *fc = get_fuse_conn_super(sb);
  250. struct fuse_req *req;
  251. struct fuse_statfs_out outarg;
  252. int err;
  253. req = fuse_get_req(fc);
  254. if (IS_ERR(req))
  255. return PTR_ERR(req);
  256. memset(&outarg, 0, sizeof(outarg));
  257. req->in.numargs = 0;
  258. req->in.h.opcode = FUSE_STATFS;
  259. req->in.h.nodeid = get_node_id(dentry->d_inode);
  260. req->out.numargs = 1;
  261. req->out.args[0].size =
  262. fc->minor < 4 ? FUSE_COMPAT_STATFS_SIZE : sizeof(outarg);
  263. req->out.args[0].value = &outarg;
  264. request_send(fc, req);
  265. err = req->out.h.error;
  266. if (!err)
  267. convert_fuse_statfs(buf, &outarg.st);
  268. fuse_put_request(fc, req);
  269. return err;
  270. }
  271. enum {
  272. OPT_FD,
  273. OPT_ROOTMODE,
  274. OPT_USER_ID,
  275. OPT_GROUP_ID,
  276. OPT_DEFAULT_PERMISSIONS,
  277. OPT_ALLOW_OTHER,
  278. OPT_MAX_READ,
  279. OPT_BLKSIZE,
  280. OPT_ERR
  281. };
  282. static match_table_t tokens = {
  283. {OPT_FD, "fd=%u"},
  284. {OPT_ROOTMODE, "rootmode=%o"},
  285. {OPT_USER_ID, "user_id=%u"},
  286. {OPT_GROUP_ID, "group_id=%u"},
  287. {OPT_DEFAULT_PERMISSIONS, "default_permissions"},
  288. {OPT_ALLOW_OTHER, "allow_other"},
  289. {OPT_MAX_READ, "max_read=%u"},
  290. {OPT_BLKSIZE, "blksize=%u"},
  291. {OPT_ERR, NULL}
  292. };
  293. static int parse_fuse_opt(char *opt, struct fuse_mount_data *d, int is_bdev)
  294. {
  295. char *p;
  296. memset(d, 0, sizeof(struct fuse_mount_data));
  297. d->max_read = ~0;
  298. d->blksize = 512;
  299. while ((p = strsep(&opt, ",")) != NULL) {
  300. int token;
  301. int value;
  302. substring_t args[MAX_OPT_ARGS];
  303. if (!*p)
  304. continue;
  305. token = match_token(p, tokens, args);
  306. switch (token) {
  307. case OPT_FD:
  308. if (match_int(&args[0], &value))
  309. return 0;
  310. d->fd = value;
  311. d->fd_present = 1;
  312. break;
  313. case OPT_ROOTMODE:
  314. if (match_octal(&args[0], &value))
  315. return 0;
  316. if (!fuse_valid_type(value))
  317. return 0;
  318. d->rootmode = value;
  319. d->rootmode_present = 1;
  320. break;
  321. case OPT_USER_ID:
  322. if (match_int(&args[0], &value))
  323. return 0;
  324. d->user_id = value;
  325. d->user_id_present = 1;
  326. break;
  327. case OPT_GROUP_ID:
  328. if (match_int(&args[0], &value))
  329. return 0;
  330. d->group_id = value;
  331. d->group_id_present = 1;
  332. break;
  333. case OPT_DEFAULT_PERMISSIONS:
  334. d->flags |= FUSE_DEFAULT_PERMISSIONS;
  335. break;
  336. case OPT_ALLOW_OTHER:
  337. d->flags |= FUSE_ALLOW_OTHER;
  338. break;
  339. case OPT_MAX_READ:
  340. if (match_int(&args[0], &value))
  341. return 0;
  342. d->max_read = value;
  343. break;
  344. case OPT_BLKSIZE:
  345. if (!is_bdev || match_int(&args[0], &value))
  346. return 0;
  347. d->blksize = value;
  348. break;
  349. default:
  350. return 0;
  351. }
  352. }
  353. if (!d->fd_present || !d->rootmode_present ||
  354. !d->user_id_present || !d->group_id_present)
  355. return 0;
  356. return 1;
  357. }
  358. static int fuse_show_options(struct seq_file *m, struct vfsmount *mnt)
  359. {
  360. struct fuse_conn *fc = get_fuse_conn_super(mnt->mnt_sb);
  361. seq_printf(m, ",user_id=%u", fc->user_id);
  362. seq_printf(m, ",group_id=%u", fc->group_id);
  363. if (fc->flags & FUSE_DEFAULT_PERMISSIONS)
  364. seq_puts(m, ",default_permissions");
  365. if (fc->flags & FUSE_ALLOW_OTHER)
  366. seq_puts(m, ",allow_other");
  367. if (fc->max_read != ~0)
  368. seq_printf(m, ",max_read=%u", fc->max_read);
  369. return 0;
  370. }
  371. static struct fuse_conn *new_conn(void)
  372. {
  373. struct fuse_conn *fc;
  374. int err;
  375. fc = kzalloc(sizeof(*fc), GFP_KERNEL);
  376. if (fc) {
  377. spin_lock_init(&fc->lock);
  378. mutex_init(&fc->inst_mutex);
  379. atomic_set(&fc->count, 1);
  380. init_waitqueue_head(&fc->waitq);
  381. init_waitqueue_head(&fc->blocked_waitq);
  382. init_waitqueue_head(&fc->reserved_req_waitq);
  383. INIT_LIST_HEAD(&fc->pending);
  384. INIT_LIST_HEAD(&fc->processing);
  385. INIT_LIST_HEAD(&fc->io);
  386. INIT_LIST_HEAD(&fc->interrupts);
  387. atomic_set(&fc->num_waiting, 0);
  388. fc->bdi.ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE;
  389. fc->bdi.unplug_io_fn = default_unplug_io_fn;
  390. err = bdi_init(&fc->bdi);
  391. if (err) {
  392. kfree(fc);
  393. fc = NULL;
  394. goto out;
  395. }
  396. fc->reqctr = 0;
  397. fc->blocked = 1;
  398. get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key));
  399. }
  400. out:
  401. return fc;
  402. }
  403. void fuse_conn_put(struct fuse_conn *fc)
  404. {
  405. if (atomic_dec_and_test(&fc->count)) {
  406. if (fc->destroy_req)
  407. fuse_request_free(fc->destroy_req);
  408. mutex_destroy(&fc->inst_mutex);
  409. bdi_destroy(&fc->bdi);
  410. kfree(fc);
  411. }
  412. }
  413. struct fuse_conn *fuse_conn_get(struct fuse_conn *fc)
  414. {
  415. atomic_inc(&fc->count);
  416. return fc;
  417. }
  418. static struct inode *get_root_inode(struct super_block *sb, unsigned mode)
  419. {
  420. struct fuse_attr attr;
  421. memset(&attr, 0, sizeof(attr));
  422. attr.mode = mode;
  423. attr.ino = FUSE_ROOT_ID;
  424. attr.nlink = 1;
  425. return fuse_iget(sb, 1, 0, &attr);
  426. }
  427. static const struct super_operations fuse_super_operations = {
  428. .alloc_inode = fuse_alloc_inode,
  429. .destroy_inode = fuse_destroy_inode,
  430. .read_inode = fuse_read_inode,
  431. .clear_inode = fuse_clear_inode,
  432. .drop_inode = generic_delete_inode,
  433. .remount_fs = fuse_remount_fs,
  434. .put_super = fuse_put_super,
  435. .umount_begin = fuse_umount_begin,
  436. .statfs = fuse_statfs,
  437. .show_options = fuse_show_options,
  438. };
  439. static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req)
  440. {
  441. struct fuse_init_out *arg = &req->misc.init_out;
  442. if (req->out.h.error || arg->major != FUSE_KERNEL_VERSION)
  443. fc->conn_error = 1;
  444. else {
  445. unsigned long ra_pages;
  446. if (arg->minor >= 6) {
  447. ra_pages = arg->max_readahead / PAGE_CACHE_SIZE;
  448. if (arg->flags & FUSE_ASYNC_READ)
  449. fc->async_read = 1;
  450. if (!(arg->flags & FUSE_POSIX_LOCKS))
  451. fc->no_lock = 1;
  452. } else {
  453. ra_pages = fc->max_read / PAGE_CACHE_SIZE;
  454. fc->no_lock = 1;
  455. }
  456. fc->bdi.ra_pages = min(fc->bdi.ra_pages, ra_pages);
  457. fc->minor = arg->minor;
  458. fc->max_write = arg->minor < 5 ? 4096 : arg->max_write;
  459. fc->conn_init = 1;
  460. }
  461. fuse_put_request(fc, req);
  462. fc->blocked = 0;
  463. wake_up_all(&fc->blocked_waitq);
  464. }
  465. static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req)
  466. {
  467. struct fuse_init_in *arg = &req->misc.init_in;
  468. arg->major = FUSE_KERNEL_VERSION;
  469. arg->minor = FUSE_KERNEL_MINOR_VERSION;
  470. arg->max_readahead = fc->bdi.ra_pages * PAGE_CACHE_SIZE;
  471. arg->flags |= FUSE_ASYNC_READ | FUSE_POSIX_LOCKS;
  472. req->in.h.opcode = FUSE_INIT;
  473. req->in.numargs = 1;
  474. req->in.args[0].size = sizeof(*arg);
  475. req->in.args[0].value = arg;
  476. req->out.numargs = 1;
  477. /* Variable length arguement used for backward compatibility
  478. with interface version < 7.5. Rest of init_out is zeroed
  479. by do_get_request(), so a short reply is not a problem */
  480. req->out.argvar = 1;
  481. req->out.args[0].size = sizeof(struct fuse_init_out);
  482. req->out.args[0].value = &req->misc.init_out;
  483. req->end = process_init_reply;
  484. request_send_background(fc, req);
  485. }
  486. static u64 conn_id(void)
  487. {
  488. static u64 ctr = 1;
  489. return ctr++;
  490. }
  491. static int fuse_fill_super(struct super_block *sb, void *data, int silent)
  492. {
  493. struct fuse_conn *fc;
  494. struct inode *root;
  495. struct fuse_mount_data d;
  496. struct file *file;
  497. struct dentry *root_dentry;
  498. struct fuse_req *init_req;
  499. int err;
  500. int is_bdev = sb->s_bdev != NULL;
  501. if (sb->s_flags & MS_MANDLOCK)
  502. return -EINVAL;
  503. if (!parse_fuse_opt((char *) data, &d, is_bdev))
  504. return -EINVAL;
  505. if (is_bdev) {
  506. #ifdef CONFIG_BLOCK
  507. if (!sb_set_blocksize(sb, d.blksize))
  508. return -EINVAL;
  509. #endif
  510. } else {
  511. sb->s_blocksize = PAGE_CACHE_SIZE;
  512. sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
  513. }
  514. sb->s_magic = FUSE_SUPER_MAGIC;
  515. sb->s_op = &fuse_super_operations;
  516. sb->s_maxbytes = MAX_LFS_FILESIZE;
  517. file = fget(d.fd);
  518. if (!file)
  519. return -EINVAL;
  520. if (file->f_op != &fuse_dev_operations)
  521. return -EINVAL;
  522. fc = new_conn();
  523. if (!fc)
  524. return -ENOMEM;
  525. fc->flags = d.flags;
  526. fc->user_id = d.user_id;
  527. fc->group_id = d.group_id;
  528. fc->max_read = d.max_read;
  529. /* Used by get_root_inode() */
  530. sb->s_fs_info = fc;
  531. err = -ENOMEM;
  532. root = get_root_inode(sb, d.rootmode);
  533. if (!root)
  534. goto err;
  535. root_dentry = d_alloc_root(root);
  536. if (!root_dentry) {
  537. iput(root);
  538. goto err;
  539. }
  540. init_req = fuse_request_alloc();
  541. if (!init_req)
  542. goto err_put_root;
  543. if (is_bdev) {
  544. fc->destroy_req = fuse_request_alloc();
  545. if (!fc->destroy_req)
  546. goto err_put_root;
  547. }
  548. mutex_lock(&fuse_mutex);
  549. err = -EINVAL;
  550. if (file->private_data)
  551. goto err_unlock;
  552. fc->id = conn_id();
  553. err = fuse_ctl_add_conn(fc);
  554. if (err)
  555. goto err_unlock;
  556. list_add_tail(&fc->entry, &fuse_conn_list);
  557. sb->s_root = root_dentry;
  558. fc->connected = 1;
  559. file->private_data = fuse_conn_get(fc);
  560. mutex_unlock(&fuse_mutex);
  561. /*
  562. * atomic_dec_and_test() in fput() provides the necessary
  563. * memory barrier for file->private_data to be visible on all
  564. * CPUs after this
  565. */
  566. fput(file);
  567. fuse_send_init(fc, init_req);
  568. return 0;
  569. err_unlock:
  570. mutex_unlock(&fuse_mutex);
  571. fuse_request_free(init_req);
  572. err_put_root:
  573. dput(root_dentry);
  574. err:
  575. fput(file);
  576. fuse_conn_put(fc);
  577. return err;
  578. }
  579. static int fuse_get_sb(struct file_system_type *fs_type,
  580. int flags, const char *dev_name,
  581. void *raw_data, struct vfsmount *mnt)
  582. {
  583. return get_sb_nodev(fs_type, flags, raw_data, fuse_fill_super, mnt);
  584. }
  585. static struct file_system_type fuse_fs_type = {
  586. .owner = THIS_MODULE,
  587. .name = "fuse",
  588. .fs_flags = FS_HAS_SUBTYPE,
  589. .get_sb = fuse_get_sb,
  590. .kill_sb = kill_anon_super,
  591. };
  592. #ifdef CONFIG_BLOCK
  593. static int fuse_get_sb_blk(struct file_system_type *fs_type,
  594. int flags, const char *dev_name,
  595. void *raw_data, struct vfsmount *mnt)
  596. {
  597. return get_sb_bdev(fs_type, flags, dev_name, raw_data, fuse_fill_super,
  598. mnt);
  599. }
  600. static struct file_system_type fuseblk_fs_type = {
  601. .owner = THIS_MODULE,
  602. .name = "fuseblk",
  603. .get_sb = fuse_get_sb_blk,
  604. .kill_sb = kill_block_super,
  605. .fs_flags = FS_REQUIRES_DEV | FS_HAS_SUBTYPE,
  606. };
  607. static inline int register_fuseblk(void)
  608. {
  609. return register_filesystem(&fuseblk_fs_type);
  610. }
  611. static inline void unregister_fuseblk(void)
  612. {
  613. unregister_filesystem(&fuseblk_fs_type);
  614. }
  615. #else
  616. static inline int register_fuseblk(void)
  617. {
  618. return 0;
  619. }
  620. static inline void unregister_fuseblk(void)
  621. {
  622. }
  623. #endif
  624. static decl_subsys(fuse, NULL, NULL);
  625. static decl_subsys(connections, NULL, NULL);
  626. static void fuse_inode_init_once(struct kmem_cache *cachep, void *foo)
  627. {
  628. struct inode * inode = foo;
  629. inode_init_once(inode);
  630. }
  631. static int __init fuse_fs_init(void)
  632. {
  633. int err;
  634. err = register_filesystem(&fuse_fs_type);
  635. if (err)
  636. goto out;
  637. err = register_fuseblk();
  638. if (err)
  639. goto out_unreg;
  640. fuse_inode_cachep = kmem_cache_create("fuse_inode",
  641. sizeof(struct fuse_inode),
  642. 0, SLAB_HWCACHE_ALIGN,
  643. fuse_inode_init_once);
  644. err = -ENOMEM;
  645. if (!fuse_inode_cachep)
  646. goto out_unreg2;
  647. return 0;
  648. out_unreg2:
  649. unregister_fuseblk();
  650. out_unreg:
  651. unregister_filesystem(&fuse_fs_type);
  652. out:
  653. return err;
  654. }
  655. static void fuse_fs_cleanup(void)
  656. {
  657. unregister_filesystem(&fuse_fs_type);
  658. unregister_fuseblk();
  659. kmem_cache_destroy(fuse_inode_cachep);
  660. }
  661. static int fuse_sysfs_init(void)
  662. {
  663. int err;
  664. kobj_set_kset_s(&fuse_subsys, fs_subsys);
  665. err = subsystem_register(&fuse_subsys);
  666. if (err)
  667. goto out_err;
  668. kobj_set_kset_s(&connections_subsys, fuse_subsys);
  669. err = subsystem_register(&connections_subsys);
  670. if (err)
  671. goto out_fuse_unregister;
  672. return 0;
  673. out_fuse_unregister:
  674. subsystem_unregister(&fuse_subsys);
  675. out_err:
  676. return err;
  677. }
  678. static void fuse_sysfs_cleanup(void)
  679. {
  680. subsystem_unregister(&connections_subsys);
  681. subsystem_unregister(&fuse_subsys);
  682. }
  683. static int __init fuse_init(void)
  684. {
  685. int res;
  686. printk("fuse init (API version %i.%i)\n",
  687. FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION);
  688. INIT_LIST_HEAD(&fuse_conn_list);
  689. res = fuse_fs_init();
  690. if (res)
  691. goto err;
  692. res = fuse_dev_init();
  693. if (res)
  694. goto err_fs_cleanup;
  695. res = fuse_sysfs_init();
  696. if (res)
  697. goto err_dev_cleanup;
  698. res = fuse_ctl_init();
  699. if (res)
  700. goto err_sysfs_cleanup;
  701. return 0;
  702. err_sysfs_cleanup:
  703. fuse_sysfs_cleanup();
  704. err_dev_cleanup:
  705. fuse_dev_cleanup();
  706. err_fs_cleanup:
  707. fuse_fs_cleanup();
  708. err:
  709. return res;
  710. }
  711. static void __exit fuse_exit(void)
  712. {
  713. printk(KERN_DEBUG "fuse exit\n");
  714. fuse_ctl_cleanup();
  715. fuse_sysfs_cleanup();
  716. fuse_fs_cleanup();
  717. fuse_dev_cleanup();
  718. }
  719. module_init(fuse_init);
  720. module_exit(fuse_exit);