file.c 20 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/kernel.h>
  11. #include <linux/sched.h>
  12. static const struct file_operations fuse_direct_io_file_operations;
  13. static int fuse_send_open(struct inode *inode, struct file *file, int isdir,
  14. struct fuse_open_out *outargp)
  15. {
  16. struct fuse_conn *fc = get_fuse_conn(inode);
  17. struct fuse_open_in inarg;
  18. struct fuse_req *req;
  19. int err;
  20. req = fuse_get_req(fc);
  21. if (IS_ERR(req))
  22. return PTR_ERR(req);
  23. memset(&inarg, 0, sizeof(inarg));
  24. inarg.flags = file->f_flags & ~(O_CREAT | O_EXCL | O_NOCTTY | O_TRUNC);
  25. req->in.h.opcode = isdir ? FUSE_OPENDIR : FUSE_OPEN;
  26. req->in.h.nodeid = get_node_id(inode);
  27. req->in.numargs = 1;
  28. req->in.args[0].size = sizeof(inarg);
  29. req->in.args[0].value = &inarg;
  30. req->out.numargs = 1;
  31. req->out.args[0].size = sizeof(*outargp);
  32. req->out.args[0].value = outargp;
  33. request_send(fc, req);
  34. err = req->out.h.error;
  35. fuse_put_request(fc, req);
  36. return err;
  37. }
  38. struct fuse_file *fuse_file_alloc(void)
  39. {
  40. struct fuse_file *ff;
  41. ff = kmalloc(sizeof(struct fuse_file), GFP_KERNEL);
  42. if (ff) {
  43. ff->reserved_req = fuse_request_alloc();
  44. if (!ff->reserved_req) {
  45. kfree(ff);
  46. ff = NULL;
  47. }
  48. }
  49. return ff;
  50. }
  51. void fuse_file_free(struct fuse_file *ff)
  52. {
  53. fuse_request_free(ff->reserved_req);
  54. kfree(ff);
  55. }
  56. void fuse_finish_open(struct inode *inode, struct file *file,
  57. struct fuse_file *ff, struct fuse_open_out *outarg)
  58. {
  59. if (outarg->open_flags & FOPEN_DIRECT_IO)
  60. file->f_op = &fuse_direct_io_file_operations;
  61. if (!(outarg->open_flags & FOPEN_KEEP_CACHE))
  62. invalidate_mapping_pages(inode->i_mapping, 0, -1);
  63. ff->fh = outarg->fh;
  64. file->private_data = ff;
  65. }
  66. int fuse_open_common(struct inode *inode, struct file *file, int isdir)
  67. {
  68. struct fuse_open_out outarg;
  69. struct fuse_file *ff;
  70. int err;
  71. /* VFS checks this, but only _after_ ->open() */
  72. if (file->f_flags & O_DIRECT)
  73. return -EINVAL;
  74. err = generic_file_open(inode, file);
  75. if (err)
  76. return err;
  77. /* If opening the root node, no lookup has been performed on
  78. it, so the attributes must be refreshed */
  79. if (get_node_id(inode) == FUSE_ROOT_ID) {
  80. err = fuse_do_getattr(inode);
  81. if (err)
  82. return err;
  83. }
  84. ff = fuse_file_alloc();
  85. if (!ff)
  86. return -ENOMEM;
  87. err = fuse_send_open(inode, file, isdir, &outarg);
  88. if (err)
  89. fuse_file_free(ff);
  90. else {
  91. if (isdir)
  92. outarg.open_flags &= ~FOPEN_DIRECT_IO;
  93. fuse_finish_open(inode, file, ff, &outarg);
  94. }
  95. return err;
  96. }
  97. struct fuse_req *fuse_release_fill(struct fuse_file *ff, u64 nodeid, int flags,
  98. int opcode)
  99. {
  100. struct fuse_req *req = ff->reserved_req;
  101. struct fuse_release_in *inarg = &req->misc.release_in;
  102. inarg->fh = ff->fh;
  103. inarg->flags = flags;
  104. req->in.h.opcode = opcode;
  105. req->in.h.nodeid = nodeid;
  106. req->in.numargs = 1;
  107. req->in.args[0].size = sizeof(struct fuse_release_in);
  108. req->in.args[0].value = inarg;
  109. kfree(ff);
  110. return req;
  111. }
  112. int fuse_release_common(struct inode *inode, struct file *file, int isdir)
  113. {
  114. struct fuse_file *ff = file->private_data;
  115. if (ff) {
  116. struct fuse_conn *fc = get_fuse_conn(inode);
  117. struct fuse_req *req;
  118. req = fuse_release_fill(ff, get_node_id(inode), file->f_flags,
  119. isdir ? FUSE_RELEASEDIR : FUSE_RELEASE);
  120. /* Hold vfsmount and dentry until release is finished */
  121. req->vfsmount = mntget(file->f_path.mnt);
  122. req->dentry = dget(file->f_path.dentry);
  123. request_send_background(fc, req);
  124. }
  125. /* Return value is ignored by VFS */
  126. return 0;
  127. }
  128. static int fuse_open(struct inode *inode, struct file *file)
  129. {
  130. return fuse_open_common(inode, file, 0);
  131. }
  132. static int fuse_release(struct inode *inode, struct file *file)
  133. {
  134. return fuse_release_common(inode, file, 0);
  135. }
  136. /*
  137. * Scramble the ID space with XTEA, so that the value of the files_struct
  138. * pointer is not exposed to userspace.
  139. */
  140. static u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id)
  141. {
  142. u32 *k = fc->scramble_key;
  143. u64 v = (unsigned long) id;
  144. u32 v0 = v;
  145. u32 v1 = v >> 32;
  146. u32 sum = 0;
  147. int i;
  148. for (i = 0; i < 32; i++) {
  149. v0 += ((v1 << 4 ^ v1 >> 5) + v1) ^ (sum + k[sum & 3]);
  150. sum += 0x9E3779B9;
  151. v1 += ((v0 << 4 ^ v0 >> 5) + v0) ^ (sum + k[sum>>11 & 3]);
  152. }
  153. return (u64) v0 + ((u64) v1 << 32);
  154. }
  155. static int fuse_flush(struct file *file, fl_owner_t id)
  156. {
  157. struct inode *inode = file->f_path.dentry->d_inode;
  158. struct fuse_conn *fc = get_fuse_conn(inode);
  159. struct fuse_file *ff = file->private_data;
  160. struct fuse_req *req;
  161. struct fuse_flush_in inarg;
  162. int err;
  163. if (is_bad_inode(inode))
  164. return -EIO;
  165. if (fc->no_flush)
  166. return 0;
  167. req = fuse_get_req_nofail(fc, file);
  168. memset(&inarg, 0, sizeof(inarg));
  169. inarg.fh = ff->fh;
  170. inarg.lock_owner = fuse_lock_owner_id(fc, id);
  171. req->in.h.opcode = FUSE_FLUSH;
  172. req->in.h.nodeid = get_node_id(inode);
  173. req->in.numargs = 1;
  174. req->in.args[0].size = sizeof(inarg);
  175. req->in.args[0].value = &inarg;
  176. req->force = 1;
  177. request_send(fc, req);
  178. err = req->out.h.error;
  179. fuse_put_request(fc, req);
  180. if (err == -ENOSYS) {
  181. fc->no_flush = 1;
  182. err = 0;
  183. }
  184. return err;
  185. }
  186. int fuse_fsync_common(struct file *file, struct dentry *de, int datasync,
  187. int isdir)
  188. {
  189. struct inode *inode = de->d_inode;
  190. struct fuse_conn *fc = get_fuse_conn(inode);
  191. struct fuse_file *ff = file->private_data;
  192. struct fuse_req *req;
  193. struct fuse_fsync_in inarg;
  194. int err;
  195. if (is_bad_inode(inode))
  196. return -EIO;
  197. if ((!isdir && fc->no_fsync) || (isdir && fc->no_fsyncdir))
  198. return 0;
  199. req = fuse_get_req(fc);
  200. if (IS_ERR(req))
  201. return PTR_ERR(req);
  202. memset(&inarg, 0, sizeof(inarg));
  203. inarg.fh = ff->fh;
  204. inarg.fsync_flags = datasync ? 1 : 0;
  205. req->in.h.opcode = isdir ? FUSE_FSYNCDIR : FUSE_FSYNC;
  206. req->in.h.nodeid = get_node_id(inode);
  207. req->in.numargs = 1;
  208. req->in.args[0].size = sizeof(inarg);
  209. req->in.args[0].value = &inarg;
  210. request_send(fc, req);
  211. err = req->out.h.error;
  212. fuse_put_request(fc, req);
  213. if (err == -ENOSYS) {
  214. if (isdir)
  215. fc->no_fsyncdir = 1;
  216. else
  217. fc->no_fsync = 1;
  218. err = 0;
  219. }
  220. return err;
  221. }
  222. static int fuse_fsync(struct file *file, struct dentry *de, int datasync)
  223. {
  224. return fuse_fsync_common(file, de, datasync, 0);
  225. }
  226. void fuse_read_fill(struct fuse_req *req, struct file *file,
  227. struct inode *inode, loff_t pos, size_t count, int opcode)
  228. {
  229. struct fuse_file *ff = file->private_data;
  230. struct fuse_read_in *inarg = &req->misc.read_in;
  231. inarg->fh = ff->fh;
  232. inarg->offset = pos;
  233. inarg->size = count;
  234. req->in.h.opcode = opcode;
  235. req->in.h.nodeid = get_node_id(inode);
  236. req->in.numargs = 1;
  237. req->in.args[0].size = sizeof(struct fuse_read_in);
  238. req->in.args[0].value = inarg;
  239. req->out.argpages = 1;
  240. req->out.argvar = 1;
  241. req->out.numargs = 1;
  242. req->out.args[0].size = count;
  243. }
  244. static size_t fuse_send_read(struct fuse_req *req, struct file *file,
  245. struct inode *inode, loff_t pos, size_t count)
  246. {
  247. struct fuse_conn *fc = get_fuse_conn(inode);
  248. fuse_read_fill(req, file, inode, pos, count, FUSE_READ);
  249. request_send(fc, req);
  250. return req->out.args[0].size;
  251. }
  252. static int fuse_readpage(struct file *file, struct page *page)
  253. {
  254. struct inode *inode = page->mapping->host;
  255. struct fuse_conn *fc = get_fuse_conn(inode);
  256. struct fuse_req *req;
  257. int err;
  258. err = -EIO;
  259. if (is_bad_inode(inode))
  260. goto out;
  261. req = fuse_get_req(fc);
  262. err = PTR_ERR(req);
  263. if (IS_ERR(req))
  264. goto out;
  265. req->out.page_zeroing = 1;
  266. req->num_pages = 1;
  267. req->pages[0] = page;
  268. fuse_send_read(req, file, inode, page_offset(page), PAGE_CACHE_SIZE);
  269. err = req->out.h.error;
  270. fuse_put_request(fc, req);
  271. if (!err)
  272. SetPageUptodate(page);
  273. fuse_invalidate_attr(inode); /* atime changed */
  274. out:
  275. unlock_page(page);
  276. return err;
  277. }
  278. static void fuse_readpages_end(struct fuse_conn *fc, struct fuse_req *req)
  279. {
  280. int i;
  281. fuse_invalidate_attr(req->pages[0]->mapping->host); /* atime changed */
  282. for (i = 0; i < req->num_pages; i++) {
  283. struct page *page = req->pages[i];
  284. if (!req->out.h.error)
  285. SetPageUptodate(page);
  286. else
  287. SetPageError(page);
  288. unlock_page(page);
  289. }
  290. fuse_put_request(fc, req);
  291. }
  292. static void fuse_send_readpages(struct fuse_req *req, struct file *file,
  293. struct inode *inode)
  294. {
  295. struct fuse_conn *fc = get_fuse_conn(inode);
  296. loff_t pos = page_offset(req->pages[0]);
  297. size_t count = req->num_pages << PAGE_CACHE_SHIFT;
  298. req->out.page_zeroing = 1;
  299. fuse_read_fill(req, file, inode, pos, count, FUSE_READ);
  300. if (fc->async_read) {
  301. get_file(file);
  302. req->file = file;
  303. req->end = fuse_readpages_end;
  304. request_send_background(fc, req);
  305. } else {
  306. request_send(fc, req);
  307. fuse_readpages_end(fc, req);
  308. }
  309. }
  310. struct fuse_readpages_data {
  311. struct fuse_req *req;
  312. struct file *file;
  313. struct inode *inode;
  314. };
  315. static int fuse_readpages_fill(void *_data, struct page *page)
  316. {
  317. struct fuse_readpages_data *data = _data;
  318. struct fuse_req *req = data->req;
  319. struct inode *inode = data->inode;
  320. struct fuse_conn *fc = get_fuse_conn(inode);
  321. if (req->num_pages &&
  322. (req->num_pages == FUSE_MAX_PAGES_PER_REQ ||
  323. (req->num_pages + 1) * PAGE_CACHE_SIZE > fc->max_read ||
  324. req->pages[req->num_pages - 1]->index + 1 != page->index)) {
  325. fuse_send_readpages(req, data->file, inode);
  326. data->req = req = fuse_get_req(fc);
  327. if (IS_ERR(req)) {
  328. unlock_page(page);
  329. return PTR_ERR(req);
  330. }
  331. }
  332. req->pages[req->num_pages] = page;
  333. req->num_pages ++;
  334. return 0;
  335. }
  336. static int fuse_readpages(struct file *file, struct address_space *mapping,
  337. struct list_head *pages, unsigned nr_pages)
  338. {
  339. struct inode *inode = mapping->host;
  340. struct fuse_conn *fc = get_fuse_conn(inode);
  341. struct fuse_readpages_data data;
  342. int err;
  343. err = -EIO;
  344. if (is_bad_inode(inode))
  345. goto out;
  346. data.file = file;
  347. data.inode = inode;
  348. data.req = fuse_get_req(fc);
  349. err = PTR_ERR(data.req);
  350. if (IS_ERR(data.req))
  351. goto out;
  352. err = read_cache_pages(mapping, pages, fuse_readpages_fill, &data);
  353. if (!err) {
  354. if (data.req->num_pages)
  355. fuse_send_readpages(data.req, file, inode);
  356. else
  357. fuse_put_request(fc, data.req);
  358. }
  359. out:
  360. return err;
  361. }
  362. static size_t fuse_send_write(struct fuse_req *req, struct file *file,
  363. struct inode *inode, loff_t pos, size_t count)
  364. {
  365. struct fuse_conn *fc = get_fuse_conn(inode);
  366. struct fuse_file *ff = file->private_data;
  367. struct fuse_write_in inarg;
  368. struct fuse_write_out outarg;
  369. memset(&inarg, 0, sizeof(struct fuse_write_in));
  370. inarg.fh = ff->fh;
  371. inarg.offset = pos;
  372. inarg.size = count;
  373. req->in.h.opcode = FUSE_WRITE;
  374. req->in.h.nodeid = get_node_id(inode);
  375. req->in.argpages = 1;
  376. req->in.numargs = 2;
  377. req->in.args[0].size = sizeof(struct fuse_write_in);
  378. req->in.args[0].value = &inarg;
  379. req->in.args[1].size = count;
  380. req->out.numargs = 1;
  381. req->out.args[0].size = sizeof(struct fuse_write_out);
  382. req->out.args[0].value = &outarg;
  383. request_send(fc, req);
  384. return outarg.size;
  385. }
  386. static int fuse_write_begin(struct file *file, struct address_space *mapping,
  387. loff_t pos, unsigned len, unsigned flags,
  388. struct page **pagep, void **fsdata)
  389. {
  390. pgoff_t index = pos >> PAGE_CACHE_SHIFT;
  391. *pagep = __grab_cache_page(mapping, index);
  392. if (!*pagep)
  393. return -ENOMEM;
  394. return 0;
  395. }
  396. static int fuse_buffered_write(struct file *file, struct inode *inode,
  397. loff_t pos, unsigned count, struct page *page)
  398. {
  399. int err;
  400. size_t nres;
  401. struct fuse_conn *fc = get_fuse_conn(inode);
  402. unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
  403. struct fuse_req *req;
  404. if (is_bad_inode(inode))
  405. return -EIO;
  406. req = fuse_get_req(fc);
  407. if (IS_ERR(req))
  408. return PTR_ERR(req);
  409. req->num_pages = 1;
  410. req->pages[0] = page;
  411. req->page_offset = offset;
  412. nres = fuse_send_write(req, file, inode, pos, count);
  413. err = req->out.h.error;
  414. fuse_put_request(fc, req);
  415. if (!err && !nres)
  416. err = -EIO;
  417. if (!err) {
  418. pos += nres;
  419. spin_lock(&fc->lock);
  420. if (pos > inode->i_size)
  421. i_size_write(inode, pos);
  422. spin_unlock(&fc->lock);
  423. if (count == PAGE_CACHE_SIZE)
  424. SetPageUptodate(page);
  425. }
  426. fuse_invalidate_attr(inode);
  427. return err ? err : nres;
  428. }
  429. static int fuse_write_end(struct file *file, struct address_space *mapping,
  430. loff_t pos, unsigned len, unsigned copied,
  431. struct page *page, void *fsdata)
  432. {
  433. struct inode *inode = mapping->host;
  434. int res = 0;
  435. if (copied)
  436. res = fuse_buffered_write(file, inode, pos, copied, page);
  437. unlock_page(page);
  438. page_cache_release(page);
  439. return res;
  440. }
  441. static void fuse_release_user_pages(struct fuse_req *req, int write)
  442. {
  443. unsigned i;
  444. for (i = 0; i < req->num_pages; i++) {
  445. struct page *page = req->pages[i];
  446. if (write)
  447. set_page_dirty_lock(page);
  448. put_page(page);
  449. }
  450. }
  451. static int fuse_get_user_pages(struct fuse_req *req, const char __user *buf,
  452. unsigned nbytes, int write)
  453. {
  454. unsigned long user_addr = (unsigned long) buf;
  455. unsigned offset = user_addr & ~PAGE_MASK;
  456. int npages;
  457. /* This doesn't work with nfsd */
  458. if (!current->mm)
  459. return -EPERM;
  460. nbytes = min(nbytes, (unsigned) FUSE_MAX_PAGES_PER_REQ << PAGE_SHIFT);
  461. npages = (nbytes + offset + PAGE_SIZE - 1) >> PAGE_SHIFT;
  462. npages = min(max(npages, 1), FUSE_MAX_PAGES_PER_REQ);
  463. down_read(&current->mm->mmap_sem);
  464. npages = get_user_pages(current, current->mm, user_addr, npages, write,
  465. 0, req->pages, NULL);
  466. up_read(&current->mm->mmap_sem);
  467. if (npages < 0)
  468. return npages;
  469. req->num_pages = npages;
  470. req->page_offset = offset;
  471. return 0;
  472. }
  473. static ssize_t fuse_direct_io(struct file *file, const char __user *buf,
  474. size_t count, loff_t *ppos, int write)
  475. {
  476. struct inode *inode = file->f_path.dentry->d_inode;
  477. struct fuse_conn *fc = get_fuse_conn(inode);
  478. size_t nmax = write ? fc->max_write : fc->max_read;
  479. loff_t pos = *ppos;
  480. ssize_t res = 0;
  481. struct fuse_req *req;
  482. if (is_bad_inode(inode))
  483. return -EIO;
  484. req = fuse_get_req(fc);
  485. if (IS_ERR(req))
  486. return PTR_ERR(req);
  487. while (count) {
  488. size_t nres;
  489. size_t nbytes = min(count, nmax);
  490. int err = fuse_get_user_pages(req, buf, nbytes, !write);
  491. if (err) {
  492. res = err;
  493. break;
  494. }
  495. nbytes = (req->num_pages << PAGE_SHIFT) - req->page_offset;
  496. nbytes = min(count, nbytes);
  497. if (write)
  498. nres = fuse_send_write(req, file, inode, pos, nbytes);
  499. else
  500. nres = fuse_send_read(req, file, inode, pos, nbytes);
  501. fuse_release_user_pages(req, !write);
  502. if (req->out.h.error) {
  503. if (!res)
  504. res = req->out.h.error;
  505. break;
  506. } else if (nres > nbytes) {
  507. res = -EIO;
  508. break;
  509. }
  510. count -= nres;
  511. res += nres;
  512. pos += nres;
  513. buf += nres;
  514. if (nres != nbytes)
  515. break;
  516. if (count) {
  517. fuse_put_request(fc, req);
  518. req = fuse_get_req(fc);
  519. if (IS_ERR(req))
  520. break;
  521. }
  522. }
  523. fuse_put_request(fc, req);
  524. if (res > 0) {
  525. if (write) {
  526. spin_lock(&fc->lock);
  527. if (pos > inode->i_size)
  528. i_size_write(inode, pos);
  529. spin_unlock(&fc->lock);
  530. }
  531. *ppos = pos;
  532. }
  533. fuse_invalidate_attr(inode);
  534. return res;
  535. }
  536. static ssize_t fuse_direct_read(struct file *file, char __user *buf,
  537. size_t count, loff_t *ppos)
  538. {
  539. return fuse_direct_io(file, buf, count, ppos, 0);
  540. }
  541. static ssize_t fuse_direct_write(struct file *file, const char __user *buf,
  542. size_t count, loff_t *ppos)
  543. {
  544. struct inode *inode = file->f_path.dentry->d_inode;
  545. ssize_t res;
  546. /* Don't allow parallel writes to the same file */
  547. mutex_lock(&inode->i_mutex);
  548. res = generic_write_checks(file, ppos, &count, 0);
  549. if (!res)
  550. res = fuse_direct_io(file, buf, count, ppos, 1);
  551. mutex_unlock(&inode->i_mutex);
  552. return res;
  553. }
  554. static int fuse_file_mmap(struct file *file, struct vm_area_struct *vma)
  555. {
  556. if ((vma->vm_flags & VM_SHARED)) {
  557. if ((vma->vm_flags & VM_WRITE))
  558. return -ENODEV;
  559. else
  560. vma->vm_flags &= ~VM_MAYWRITE;
  561. }
  562. return generic_file_mmap(file, vma);
  563. }
  564. static int fuse_set_page_dirty(struct page *page)
  565. {
  566. printk("fuse_set_page_dirty: should not happen\n");
  567. dump_stack();
  568. return 0;
  569. }
  570. static int convert_fuse_file_lock(const struct fuse_file_lock *ffl,
  571. struct file_lock *fl)
  572. {
  573. switch (ffl->type) {
  574. case F_UNLCK:
  575. break;
  576. case F_RDLCK:
  577. case F_WRLCK:
  578. if (ffl->start > OFFSET_MAX || ffl->end > OFFSET_MAX ||
  579. ffl->end < ffl->start)
  580. return -EIO;
  581. fl->fl_start = ffl->start;
  582. fl->fl_end = ffl->end;
  583. fl->fl_pid = ffl->pid;
  584. break;
  585. default:
  586. return -EIO;
  587. }
  588. fl->fl_type = ffl->type;
  589. return 0;
  590. }
  591. static void fuse_lk_fill(struct fuse_req *req, struct file *file,
  592. const struct file_lock *fl, int opcode, pid_t pid)
  593. {
  594. struct inode *inode = file->f_path.dentry->d_inode;
  595. struct fuse_conn *fc = get_fuse_conn(inode);
  596. struct fuse_file *ff = file->private_data;
  597. struct fuse_lk_in *arg = &req->misc.lk_in;
  598. arg->fh = ff->fh;
  599. arg->owner = fuse_lock_owner_id(fc, fl->fl_owner);
  600. arg->lk.start = fl->fl_start;
  601. arg->lk.end = fl->fl_end;
  602. arg->lk.type = fl->fl_type;
  603. arg->lk.pid = pid;
  604. req->in.h.opcode = opcode;
  605. req->in.h.nodeid = get_node_id(inode);
  606. req->in.numargs = 1;
  607. req->in.args[0].size = sizeof(*arg);
  608. req->in.args[0].value = arg;
  609. }
  610. static int fuse_getlk(struct file *file, struct file_lock *fl)
  611. {
  612. struct inode *inode = file->f_path.dentry->d_inode;
  613. struct fuse_conn *fc = get_fuse_conn(inode);
  614. struct fuse_req *req;
  615. struct fuse_lk_out outarg;
  616. int err;
  617. req = fuse_get_req(fc);
  618. if (IS_ERR(req))
  619. return PTR_ERR(req);
  620. fuse_lk_fill(req, file, fl, FUSE_GETLK, 0);
  621. req->out.numargs = 1;
  622. req->out.args[0].size = sizeof(outarg);
  623. req->out.args[0].value = &outarg;
  624. request_send(fc, req);
  625. err = req->out.h.error;
  626. fuse_put_request(fc, req);
  627. if (!err)
  628. err = convert_fuse_file_lock(&outarg.lk, fl);
  629. return err;
  630. }
  631. static int fuse_setlk(struct file *file, struct file_lock *fl)
  632. {
  633. struct inode *inode = file->f_path.dentry->d_inode;
  634. struct fuse_conn *fc = get_fuse_conn(inode);
  635. struct fuse_req *req;
  636. int opcode = (fl->fl_flags & FL_SLEEP) ? FUSE_SETLKW : FUSE_SETLK;
  637. pid_t pid = fl->fl_type != F_UNLCK ? current->tgid : 0;
  638. int err;
  639. /* Unlock on close is handled by the flush method */
  640. if (fl->fl_flags & FL_CLOSE)
  641. return 0;
  642. req = fuse_get_req(fc);
  643. if (IS_ERR(req))
  644. return PTR_ERR(req);
  645. fuse_lk_fill(req, file, fl, opcode, pid);
  646. request_send(fc, req);
  647. err = req->out.h.error;
  648. /* locking is restartable */
  649. if (err == -EINTR)
  650. err = -ERESTARTSYS;
  651. fuse_put_request(fc, req);
  652. return err;
  653. }
  654. static int fuse_file_lock(struct file *file, int cmd, struct file_lock *fl)
  655. {
  656. struct inode *inode = file->f_path.dentry->d_inode;
  657. struct fuse_conn *fc = get_fuse_conn(inode);
  658. int err;
  659. if (cmd == F_GETLK) {
  660. if (fc->no_lock) {
  661. posix_test_lock(file, fl);
  662. err = 0;
  663. } else
  664. err = fuse_getlk(file, fl);
  665. } else {
  666. if (fc->no_lock)
  667. err = posix_lock_file_wait(file, fl);
  668. else
  669. err = fuse_setlk(file, fl);
  670. }
  671. return err;
  672. }
  673. static sector_t fuse_bmap(struct address_space *mapping, sector_t block)
  674. {
  675. struct inode *inode = mapping->host;
  676. struct fuse_conn *fc = get_fuse_conn(inode);
  677. struct fuse_req *req;
  678. struct fuse_bmap_in inarg;
  679. struct fuse_bmap_out outarg;
  680. int err;
  681. if (!inode->i_sb->s_bdev || fc->no_bmap)
  682. return 0;
  683. req = fuse_get_req(fc);
  684. if (IS_ERR(req))
  685. return 0;
  686. memset(&inarg, 0, sizeof(inarg));
  687. inarg.block = block;
  688. inarg.blocksize = inode->i_sb->s_blocksize;
  689. req->in.h.opcode = FUSE_BMAP;
  690. req->in.h.nodeid = get_node_id(inode);
  691. req->in.numargs = 1;
  692. req->in.args[0].size = sizeof(inarg);
  693. req->in.args[0].value = &inarg;
  694. req->out.numargs = 1;
  695. req->out.args[0].size = sizeof(outarg);
  696. req->out.args[0].value = &outarg;
  697. request_send(fc, req);
  698. err = req->out.h.error;
  699. fuse_put_request(fc, req);
  700. if (err == -ENOSYS)
  701. fc->no_bmap = 1;
  702. return err ? 0 : outarg.block;
  703. }
  704. static const struct file_operations fuse_file_operations = {
  705. .llseek = generic_file_llseek,
  706. .read = do_sync_read,
  707. .aio_read = generic_file_aio_read,
  708. .write = do_sync_write,
  709. .aio_write = generic_file_aio_write,
  710. .mmap = fuse_file_mmap,
  711. .open = fuse_open,
  712. .flush = fuse_flush,
  713. .release = fuse_release,
  714. .fsync = fuse_fsync,
  715. .lock = fuse_file_lock,
  716. .splice_read = generic_file_splice_read,
  717. };
  718. static const struct file_operations fuse_direct_io_file_operations = {
  719. .llseek = generic_file_llseek,
  720. .read = fuse_direct_read,
  721. .write = fuse_direct_write,
  722. .open = fuse_open,
  723. .flush = fuse_flush,
  724. .release = fuse_release,
  725. .fsync = fuse_fsync,
  726. .lock = fuse_file_lock,
  727. /* no mmap and splice_read */
  728. };
  729. static const struct address_space_operations fuse_file_aops = {
  730. .readpage = fuse_readpage,
  731. .write_begin = fuse_write_begin,
  732. .write_end = fuse_write_end,
  733. .readpages = fuse_readpages,
  734. .set_page_dirty = fuse_set_page_dirty,
  735. .bmap = fuse_bmap,
  736. };
  737. void fuse_init_file_inode(struct inode *inode)
  738. {
  739. inode->i_fop = &fuse_file_operations;
  740. inode->i_data.a_ops = &fuse_file_aops;
  741. }