vfs_file.c 21 KB

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  1. /*
  2. * linux/fs/9p/vfs_file.c
  3. *
  4. * This file contians vfs file ops for 9P2000.
  5. *
  6. * Copyright (C) 2004 by Eric Van Hensbergen <ericvh@gmail.com>
  7. * Copyright (C) 2002 by Ron Minnich <rminnich@lanl.gov>
  8. *
  9. * This program is free software; you can redistribute it and/or modify
  10. * it under the terms of the GNU General Public License version 2
  11. * as published by the Free Software Foundation.
  12. *
  13. * This program is distributed in the hope that it will be useful,
  14. * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15. * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16. * GNU General Public License for more details.
  17. *
  18. * You should have received a copy of the GNU General Public License
  19. * along with this program; if not, write to:
  20. * Free Software Foundation
  21. * 51 Franklin Street, Fifth Floor
  22. * Boston, MA 02111-1301 USA
  23. *
  24. */
  25. #include <linux/module.h>
  26. #include <linux/errno.h>
  27. #include <linux/fs.h>
  28. #include <linux/sched.h>
  29. #include <linux/file.h>
  30. #include <linux/stat.h>
  31. #include <linux/string.h>
  32. #include <linux/inet.h>
  33. #include <linux/list.h>
  34. #include <linux/pagemap.h>
  35. #include <linux/utsname.h>
  36. #include <asm/uaccess.h>
  37. #include <linux/idr.h>
  38. #include <net/9p/9p.h>
  39. #include <net/9p/client.h>
  40. #include "v9fs.h"
  41. #include "v9fs_vfs.h"
  42. #include "fid.h"
  43. #include "cache.h"
  44. static const struct vm_operations_struct v9fs_file_vm_ops;
  45. static const struct vm_operations_struct v9fs_mmap_file_vm_ops;
  46. /**
  47. * v9fs_file_open - open a file (or directory)
  48. * @inode: inode to be opened
  49. * @file: file being opened
  50. *
  51. */
  52. int v9fs_file_open(struct inode *inode, struct file *file)
  53. {
  54. int err;
  55. struct v9fs_inode *v9inode;
  56. struct v9fs_session_info *v9ses;
  57. struct p9_fid *fid;
  58. int omode;
  59. p9_debug(P9_DEBUG_VFS, "inode: %p file: %p\n", inode, file);
  60. v9inode = V9FS_I(inode);
  61. v9ses = v9fs_inode2v9ses(inode);
  62. if (v9fs_proto_dotl(v9ses))
  63. omode = v9fs_open_to_dotl_flags(file->f_flags);
  64. else
  65. omode = v9fs_uflags2omode(file->f_flags,
  66. v9fs_proto_dotu(v9ses));
  67. fid = file->private_data;
  68. if (!fid) {
  69. fid = v9fs_fid_clone(file->f_path.dentry);
  70. if (IS_ERR(fid))
  71. return PTR_ERR(fid);
  72. err = p9_client_open(fid, omode);
  73. if (err < 0) {
  74. p9_client_clunk(fid);
  75. return err;
  76. }
  77. if ((file->f_flags & O_APPEND) &&
  78. (!v9fs_proto_dotu(v9ses) && !v9fs_proto_dotl(v9ses)))
  79. generic_file_llseek(file, 0, SEEK_END);
  80. }
  81. file->private_data = fid;
  82. mutex_lock(&v9inode->v_mutex);
  83. if ((v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE) &&
  84. !v9inode->writeback_fid &&
  85. ((file->f_flags & O_ACCMODE) != O_RDONLY)) {
  86. /*
  87. * clone a fid and add it to writeback_fid
  88. * we do it during open time instead of
  89. * page dirty time via write_begin/page_mkwrite
  90. * because we want write after unlink usecase
  91. * to work.
  92. */
  93. fid = v9fs_writeback_fid(file->f_path.dentry);
  94. if (IS_ERR(fid)) {
  95. err = PTR_ERR(fid);
  96. mutex_unlock(&v9inode->v_mutex);
  97. goto out_error;
  98. }
  99. v9inode->writeback_fid = (void *) fid;
  100. }
  101. mutex_unlock(&v9inode->v_mutex);
  102. if (v9ses->cache == CACHE_LOOSE || v9ses->cache == CACHE_FSCACHE)
  103. v9fs_cache_inode_set_cookie(inode, file);
  104. return 0;
  105. out_error:
  106. p9_client_clunk(file->private_data);
  107. file->private_data = NULL;
  108. return err;
  109. }
  110. /**
  111. * v9fs_file_lock - lock a file (or directory)
  112. * @filp: file to be locked
  113. * @cmd: lock command
  114. * @fl: file lock structure
  115. *
  116. * Bugs: this looks like a local only lock, we should extend into 9P
  117. * by using open exclusive
  118. */
  119. static int v9fs_file_lock(struct file *filp, int cmd, struct file_lock *fl)
  120. {
  121. int res = 0;
  122. struct inode *inode = file_inode(filp);
  123. p9_debug(P9_DEBUG_VFS, "filp: %p lock: %p\n", filp, fl);
  124. /* No mandatory locks */
  125. if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
  126. return -ENOLCK;
  127. if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
  128. filemap_write_and_wait(inode->i_mapping);
  129. invalidate_mapping_pages(&inode->i_data, 0, -1);
  130. }
  131. return res;
  132. }
  133. static int v9fs_file_do_lock(struct file *filp, int cmd, struct file_lock *fl)
  134. {
  135. struct p9_flock flock;
  136. struct p9_fid *fid;
  137. uint8_t status;
  138. int res = 0;
  139. unsigned char fl_type;
  140. fid = filp->private_data;
  141. BUG_ON(fid == NULL);
  142. if ((fl->fl_flags & FL_POSIX) != FL_POSIX)
  143. BUG();
  144. res = posix_lock_file_wait(filp, fl);
  145. if (res < 0)
  146. goto out;
  147. /* convert posix lock to p9 tlock args */
  148. memset(&flock, 0, sizeof(flock));
  149. /* map the lock type */
  150. switch (fl->fl_type) {
  151. case F_RDLCK:
  152. flock.type = P9_LOCK_TYPE_RDLCK;
  153. break;
  154. case F_WRLCK:
  155. flock.type = P9_LOCK_TYPE_WRLCK;
  156. break;
  157. case F_UNLCK:
  158. flock.type = P9_LOCK_TYPE_UNLCK;
  159. break;
  160. }
  161. flock.start = fl->fl_start;
  162. if (fl->fl_end == OFFSET_MAX)
  163. flock.length = 0;
  164. else
  165. flock.length = fl->fl_end - fl->fl_start + 1;
  166. flock.proc_id = fl->fl_pid;
  167. flock.client_id = fid->clnt->name;
  168. if (IS_SETLKW(cmd))
  169. flock.flags = P9_LOCK_FLAGS_BLOCK;
  170. /*
  171. * if its a blocked request and we get P9_LOCK_BLOCKED as the status
  172. * for lock request, keep on trying
  173. */
  174. for (;;) {
  175. res = p9_client_lock_dotl(fid, &flock, &status);
  176. if (res < 0)
  177. break;
  178. if (status != P9_LOCK_BLOCKED)
  179. break;
  180. if (status == P9_LOCK_BLOCKED && !IS_SETLKW(cmd))
  181. break;
  182. if (schedule_timeout_interruptible(P9_LOCK_TIMEOUT) != 0)
  183. break;
  184. }
  185. /* map 9p status to VFS status */
  186. switch (status) {
  187. case P9_LOCK_SUCCESS:
  188. res = 0;
  189. break;
  190. case P9_LOCK_BLOCKED:
  191. res = -EAGAIN;
  192. break;
  193. case P9_LOCK_ERROR:
  194. case P9_LOCK_GRACE:
  195. res = -ENOLCK;
  196. break;
  197. default:
  198. BUG();
  199. }
  200. /*
  201. * incase server returned error for lock request, revert
  202. * it locally
  203. */
  204. if (res < 0 && fl->fl_type != F_UNLCK) {
  205. fl_type = fl->fl_type;
  206. fl->fl_type = F_UNLCK;
  207. res = posix_lock_file_wait(filp, fl);
  208. fl->fl_type = fl_type;
  209. }
  210. out:
  211. return res;
  212. }
  213. static int v9fs_file_getlock(struct file *filp, struct file_lock *fl)
  214. {
  215. struct p9_getlock glock;
  216. struct p9_fid *fid;
  217. int res = 0;
  218. fid = filp->private_data;
  219. BUG_ON(fid == NULL);
  220. posix_test_lock(filp, fl);
  221. /*
  222. * if we have a conflicting lock locally, no need to validate
  223. * with server
  224. */
  225. if (fl->fl_type != F_UNLCK)
  226. return res;
  227. /* convert posix lock to p9 tgetlock args */
  228. memset(&glock, 0, sizeof(glock));
  229. glock.type = P9_LOCK_TYPE_UNLCK;
  230. glock.start = fl->fl_start;
  231. if (fl->fl_end == OFFSET_MAX)
  232. glock.length = 0;
  233. else
  234. glock.length = fl->fl_end - fl->fl_start + 1;
  235. glock.proc_id = fl->fl_pid;
  236. glock.client_id = fid->clnt->name;
  237. res = p9_client_getlock_dotl(fid, &glock);
  238. if (res < 0)
  239. return res;
  240. /* map 9p lock type to os lock type */
  241. switch (glock.type) {
  242. case P9_LOCK_TYPE_RDLCK:
  243. fl->fl_type = F_RDLCK;
  244. break;
  245. case P9_LOCK_TYPE_WRLCK:
  246. fl->fl_type = F_WRLCK;
  247. break;
  248. case P9_LOCK_TYPE_UNLCK:
  249. fl->fl_type = F_UNLCK;
  250. break;
  251. }
  252. if (glock.type != P9_LOCK_TYPE_UNLCK) {
  253. fl->fl_start = glock.start;
  254. if (glock.length == 0)
  255. fl->fl_end = OFFSET_MAX;
  256. else
  257. fl->fl_end = glock.start + glock.length - 1;
  258. fl->fl_pid = glock.proc_id;
  259. }
  260. return res;
  261. }
  262. /**
  263. * v9fs_file_lock_dotl - lock a file (or directory)
  264. * @filp: file to be locked
  265. * @cmd: lock command
  266. * @fl: file lock structure
  267. *
  268. */
  269. static int v9fs_file_lock_dotl(struct file *filp, int cmd, struct file_lock *fl)
  270. {
  271. struct inode *inode = file_inode(filp);
  272. int ret = -ENOLCK;
  273. p9_debug(P9_DEBUG_VFS, "filp: %p cmd:%d lock: %p name: %pD\n",
  274. filp, cmd, fl, filp);
  275. /* No mandatory locks */
  276. if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
  277. goto out_err;
  278. if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
  279. filemap_write_and_wait(inode->i_mapping);
  280. invalidate_mapping_pages(&inode->i_data, 0, -1);
  281. }
  282. if (IS_SETLK(cmd) || IS_SETLKW(cmd))
  283. ret = v9fs_file_do_lock(filp, cmd, fl);
  284. else if (IS_GETLK(cmd))
  285. ret = v9fs_file_getlock(filp, fl);
  286. else
  287. ret = -EINVAL;
  288. out_err:
  289. return ret;
  290. }
  291. /**
  292. * v9fs_file_flock_dotl - lock a file
  293. * @filp: file to be locked
  294. * @cmd: lock command
  295. * @fl: file lock structure
  296. *
  297. */
  298. static int v9fs_file_flock_dotl(struct file *filp, int cmd,
  299. struct file_lock *fl)
  300. {
  301. struct inode *inode = file_inode(filp);
  302. int ret = -ENOLCK;
  303. p9_debug(P9_DEBUG_VFS, "filp: %p cmd:%d lock: %p name: %pD\n",
  304. filp, cmd, fl, filp);
  305. /* No mandatory locks */
  306. if (__mandatory_lock(inode) && fl->fl_type != F_UNLCK)
  307. goto out_err;
  308. if (!(fl->fl_flags & FL_FLOCK))
  309. goto out_err;
  310. if ((IS_SETLK(cmd) || IS_SETLKW(cmd)) && fl->fl_type != F_UNLCK) {
  311. filemap_write_and_wait(inode->i_mapping);
  312. invalidate_mapping_pages(&inode->i_data, 0, -1);
  313. }
  314. /* Convert flock to posix lock */
  315. fl->fl_flags |= FL_POSIX;
  316. fl->fl_flags ^= FL_FLOCK;
  317. if (IS_SETLK(cmd) | IS_SETLKW(cmd))
  318. ret = v9fs_file_do_lock(filp, cmd, fl);
  319. else
  320. ret = -EINVAL;
  321. out_err:
  322. return ret;
  323. }
  324. /**
  325. * v9fs_fid_readn - read from a fid
  326. * @fid: fid to read
  327. * @data: data buffer to read data into
  328. * @udata: user data buffer to read data into
  329. * @count: size of buffer
  330. * @offset: offset at which to read data
  331. *
  332. */
  333. ssize_t
  334. v9fs_fid_readn(struct p9_fid *fid, char *data, char __user *udata, u32 count,
  335. u64 offset)
  336. {
  337. int n, total, size;
  338. p9_debug(P9_DEBUG_VFS, "fid %d offset %llu count %d\n",
  339. fid->fid, (long long unsigned)offset, count);
  340. n = 0;
  341. total = 0;
  342. size = fid->iounit ? fid->iounit : fid->clnt->msize - P9_IOHDRSZ;
  343. do {
  344. n = p9_client_read(fid, data, udata, offset, count);
  345. if (n <= 0)
  346. break;
  347. if (data)
  348. data += n;
  349. if (udata)
  350. udata += n;
  351. offset += n;
  352. count -= n;
  353. total += n;
  354. } while (count > 0 && n == size);
  355. if (n < 0)
  356. total = n;
  357. return total;
  358. }
  359. /**
  360. * v9fs_file_readn - read from a file
  361. * @filp: file pointer to read
  362. * @data: data buffer to read data into
  363. * @udata: user data buffer to read data into
  364. * @count: size of buffer
  365. * @offset: offset at which to read data
  366. *
  367. */
  368. ssize_t
  369. v9fs_file_readn(struct file *filp, char *data, char __user *udata, u32 count,
  370. u64 offset)
  371. {
  372. return v9fs_fid_readn(filp->private_data, data, udata, count, offset);
  373. }
  374. /**
  375. * v9fs_file_read - read from a file
  376. * @filp: file pointer to read
  377. * @udata: user data buffer to read data into
  378. * @count: size of buffer
  379. * @offset: offset at which to read data
  380. *
  381. */
  382. static ssize_t
  383. v9fs_file_read(struct file *filp, char __user *udata, size_t count,
  384. loff_t * offset)
  385. {
  386. int ret;
  387. struct p9_fid *fid;
  388. size_t size;
  389. p9_debug(P9_DEBUG_VFS, "count %zu offset %lld\n", count, *offset);
  390. fid = filp->private_data;
  391. size = fid->iounit ? fid->iounit : fid->clnt->msize - P9_IOHDRSZ;
  392. if (count > size)
  393. ret = v9fs_file_readn(filp, NULL, udata, count, *offset);
  394. else
  395. ret = p9_client_read(fid, NULL, udata, *offset, count);
  396. if (ret > 0)
  397. *offset += ret;
  398. return ret;
  399. }
  400. ssize_t
  401. v9fs_file_write_internal(struct inode *inode, struct p9_fid *fid,
  402. const char __user *data, size_t count,
  403. loff_t *offset, int invalidate)
  404. {
  405. int n;
  406. loff_t i_size;
  407. size_t total = 0;
  408. loff_t origin = *offset;
  409. unsigned long pg_start, pg_end;
  410. p9_debug(P9_DEBUG_VFS, "data %p count %d offset %x\n",
  411. data, (int)count, (int)*offset);
  412. do {
  413. n = p9_client_write(fid, NULL, data+total, origin+total, count);
  414. if (n <= 0)
  415. break;
  416. count -= n;
  417. total += n;
  418. } while (count > 0);
  419. if (invalidate && (total > 0)) {
  420. pg_start = origin >> PAGE_CACHE_SHIFT;
  421. pg_end = (origin + total - 1) >> PAGE_CACHE_SHIFT;
  422. if (inode->i_mapping && inode->i_mapping->nrpages)
  423. invalidate_inode_pages2_range(inode->i_mapping,
  424. pg_start, pg_end);
  425. *offset += total;
  426. i_size = i_size_read(inode);
  427. if (*offset > i_size) {
  428. inode_add_bytes(inode, *offset - i_size);
  429. i_size_write(inode, *offset);
  430. }
  431. }
  432. if (n < 0)
  433. return n;
  434. return total;
  435. }
  436. /**
  437. * v9fs_file_write - write to a file
  438. * @filp: file pointer to write
  439. * @data: data buffer to write data from
  440. * @count: size of buffer
  441. * @offset: offset at which to write data
  442. *
  443. */
  444. static ssize_t
  445. v9fs_file_write(struct file *filp, const char __user * data,
  446. size_t count, loff_t *offset)
  447. {
  448. ssize_t retval = 0;
  449. loff_t origin = *offset;
  450. retval = generic_write_checks(filp, &origin, &count, 0);
  451. if (retval)
  452. goto out;
  453. retval = -EINVAL;
  454. if ((ssize_t) count < 0)
  455. goto out;
  456. retval = 0;
  457. if (!count)
  458. goto out;
  459. retval = v9fs_file_write_internal(file_inode(filp),
  460. filp->private_data,
  461. data, count, &origin, 1);
  462. /* update offset on successful write */
  463. if (retval > 0)
  464. *offset = origin;
  465. out:
  466. return retval;
  467. }
  468. static int v9fs_file_fsync(struct file *filp, loff_t start, loff_t end,
  469. int datasync)
  470. {
  471. struct p9_fid *fid;
  472. struct inode *inode = filp->f_mapping->host;
  473. struct p9_wstat wstat;
  474. int retval;
  475. retval = filemap_write_and_wait_range(inode->i_mapping, start, end);
  476. if (retval)
  477. return retval;
  478. mutex_lock(&inode->i_mutex);
  479. p9_debug(P9_DEBUG_VFS, "filp %p datasync %x\n", filp, datasync);
  480. fid = filp->private_data;
  481. v9fs_blank_wstat(&wstat);
  482. retval = p9_client_wstat(fid, &wstat);
  483. mutex_unlock(&inode->i_mutex);
  484. return retval;
  485. }
  486. int v9fs_file_fsync_dotl(struct file *filp, loff_t start, loff_t end,
  487. int datasync)
  488. {
  489. struct p9_fid *fid;
  490. struct inode *inode = filp->f_mapping->host;
  491. int retval;
  492. retval = filemap_write_and_wait_range(inode->i_mapping, start, end);
  493. if (retval)
  494. return retval;
  495. mutex_lock(&inode->i_mutex);
  496. p9_debug(P9_DEBUG_VFS, "filp %p datasync %x\n", filp, datasync);
  497. fid = filp->private_data;
  498. retval = p9_client_fsync(fid, datasync);
  499. mutex_unlock(&inode->i_mutex);
  500. return retval;
  501. }
  502. static int
  503. v9fs_file_mmap(struct file *filp, struct vm_area_struct *vma)
  504. {
  505. int retval;
  506. retval = generic_file_mmap(filp, vma);
  507. if (!retval)
  508. vma->vm_ops = &v9fs_file_vm_ops;
  509. return retval;
  510. }
  511. static int
  512. v9fs_mmap_file_mmap(struct file *filp, struct vm_area_struct *vma)
  513. {
  514. int retval;
  515. struct inode *inode;
  516. struct v9fs_inode *v9inode;
  517. struct p9_fid *fid;
  518. inode = file_inode(filp);
  519. v9inode = V9FS_I(inode);
  520. mutex_lock(&v9inode->v_mutex);
  521. if (!v9inode->writeback_fid &&
  522. (vma->vm_flags & VM_WRITE)) {
  523. /*
  524. * clone a fid and add it to writeback_fid
  525. * we do it during mmap instead of
  526. * page dirty time via write_begin/page_mkwrite
  527. * because we want write after unlink usecase
  528. * to work.
  529. */
  530. fid = v9fs_writeback_fid(filp->f_path.dentry);
  531. if (IS_ERR(fid)) {
  532. retval = PTR_ERR(fid);
  533. mutex_unlock(&v9inode->v_mutex);
  534. return retval;
  535. }
  536. v9inode->writeback_fid = (void *) fid;
  537. }
  538. mutex_unlock(&v9inode->v_mutex);
  539. retval = generic_file_mmap(filp, vma);
  540. if (!retval)
  541. vma->vm_ops = &v9fs_mmap_file_vm_ops;
  542. return retval;
  543. }
  544. static int
  545. v9fs_vm_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
  546. {
  547. struct v9fs_inode *v9inode;
  548. struct page *page = vmf->page;
  549. struct file *filp = vma->vm_file;
  550. struct inode *inode = file_inode(filp);
  551. p9_debug(P9_DEBUG_VFS, "page %p fid %lx\n",
  552. page, (unsigned long)filp->private_data);
  553. /* Update file times before taking page lock */
  554. file_update_time(filp);
  555. v9inode = V9FS_I(inode);
  556. /* make sure the cache has finished storing the page */
  557. v9fs_fscache_wait_on_page_write(inode, page);
  558. BUG_ON(!v9inode->writeback_fid);
  559. lock_page(page);
  560. if (page->mapping != inode->i_mapping)
  561. goto out_unlock;
  562. wait_for_stable_page(page);
  563. return VM_FAULT_LOCKED;
  564. out_unlock:
  565. unlock_page(page);
  566. return VM_FAULT_NOPAGE;
  567. }
  568. static ssize_t
  569. v9fs_direct_read(struct file *filp, char __user *udata, size_t count,
  570. loff_t *offsetp)
  571. {
  572. loff_t size, offset;
  573. struct inode *inode;
  574. struct address_space *mapping;
  575. offset = *offsetp;
  576. mapping = filp->f_mapping;
  577. inode = mapping->host;
  578. if (!count)
  579. return 0;
  580. size = i_size_read(inode);
  581. if (offset < size)
  582. filemap_write_and_wait_range(mapping, offset,
  583. offset + count - 1);
  584. return v9fs_file_read(filp, udata, count, offsetp);
  585. }
  586. /**
  587. * v9fs_cached_file_read - read from a file
  588. * @filp: file pointer to read
  589. * @data: user data buffer to read data into
  590. * @count: size of buffer
  591. * @offset: offset at which to read data
  592. *
  593. */
  594. static ssize_t
  595. v9fs_cached_file_read(struct file *filp, char __user *data, size_t count,
  596. loff_t *offset)
  597. {
  598. if (filp->f_flags & O_DIRECT)
  599. return v9fs_direct_read(filp, data, count, offset);
  600. return new_sync_read(filp, data, count, offset);
  601. }
  602. /**
  603. * v9fs_mmap_file_read - read from a file
  604. * @filp: file pointer to read
  605. * @data: user data buffer to read data into
  606. * @count: size of buffer
  607. * @offset: offset at which to read data
  608. *
  609. */
  610. static ssize_t
  611. v9fs_mmap_file_read(struct file *filp, char __user *data, size_t count,
  612. loff_t *offset)
  613. {
  614. /* TODO: Check if there are dirty pages */
  615. return v9fs_file_read(filp, data, count, offset);
  616. }
  617. static ssize_t
  618. v9fs_direct_write(struct file *filp, const char __user * data,
  619. size_t count, loff_t *offsetp)
  620. {
  621. loff_t offset;
  622. ssize_t retval;
  623. struct inode *inode;
  624. struct address_space *mapping;
  625. offset = *offsetp;
  626. mapping = filp->f_mapping;
  627. inode = mapping->host;
  628. if (!count)
  629. return 0;
  630. mutex_lock(&inode->i_mutex);
  631. retval = filemap_write_and_wait_range(mapping, offset,
  632. offset + count - 1);
  633. if (retval)
  634. goto err_out;
  635. /*
  636. * After a write we want buffered reads to be sure to go to disk to get
  637. * the new data. We invalidate clean cached page from the region we're
  638. * about to write. We do this *before* the write so that if we fail
  639. * here we fall back to buffered write
  640. */
  641. if (mapping->nrpages) {
  642. pgoff_t pg_start = offset >> PAGE_CACHE_SHIFT;
  643. pgoff_t pg_end = (offset + count - 1) >> PAGE_CACHE_SHIFT;
  644. retval = invalidate_inode_pages2_range(mapping,
  645. pg_start, pg_end);
  646. /*
  647. * If a page can not be invalidated, fall back
  648. * to buffered write.
  649. */
  650. if (retval) {
  651. if (retval == -EBUSY)
  652. goto buff_write;
  653. goto err_out;
  654. }
  655. }
  656. retval = v9fs_file_write(filp, data, count, offsetp);
  657. err_out:
  658. mutex_unlock(&inode->i_mutex);
  659. return retval;
  660. buff_write:
  661. mutex_unlock(&inode->i_mutex);
  662. return new_sync_write(filp, data, count, offsetp);
  663. }
  664. /**
  665. * v9fs_cached_file_write - write to a file
  666. * @filp: file pointer to write
  667. * @data: data buffer to write data from
  668. * @count: size of buffer
  669. * @offset: offset at which to write data
  670. *
  671. */
  672. static ssize_t
  673. v9fs_cached_file_write(struct file *filp, const char __user * data,
  674. size_t count, loff_t *offset)
  675. {
  676. if (filp->f_flags & O_DIRECT)
  677. return v9fs_direct_write(filp, data, count, offset);
  678. return new_sync_write(filp, data, count, offset);
  679. }
  680. /**
  681. * v9fs_mmap_file_write - write to a file
  682. * @filp: file pointer to write
  683. * @data: data buffer to write data from
  684. * @count: size of buffer
  685. * @offset: offset at which to write data
  686. *
  687. */
  688. static ssize_t
  689. v9fs_mmap_file_write(struct file *filp, const char __user *data,
  690. size_t count, loff_t *offset)
  691. {
  692. /*
  693. * TODO: invalidate mmaps on filp's inode between
  694. * offset and offset+count
  695. */
  696. return v9fs_file_write(filp, data, count, offset);
  697. }
  698. static void v9fs_mmap_vm_close(struct vm_area_struct *vma)
  699. {
  700. struct inode *inode;
  701. struct writeback_control wbc = {
  702. .nr_to_write = LONG_MAX,
  703. .sync_mode = WB_SYNC_ALL,
  704. .range_start = vma->vm_pgoff * PAGE_SIZE,
  705. /* absolute end, byte at end included */
  706. .range_end = vma->vm_pgoff * PAGE_SIZE +
  707. (vma->vm_end - vma->vm_start - 1),
  708. };
  709. p9_debug(P9_DEBUG_VFS, "9p VMA close, %p, flushing", vma);
  710. inode = file_inode(vma->vm_file);
  711. if (!mapping_cap_writeback_dirty(inode->i_mapping))
  712. wbc.nr_to_write = 0;
  713. might_sleep();
  714. sync_inode(inode, &wbc);
  715. }
  716. static const struct vm_operations_struct v9fs_file_vm_ops = {
  717. .fault = filemap_fault,
  718. .map_pages = filemap_map_pages,
  719. .page_mkwrite = v9fs_vm_page_mkwrite,
  720. .remap_pages = generic_file_remap_pages,
  721. };
  722. static const struct vm_operations_struct v9fs_mmap_file_vm_ops = {
  723. .close = v9fs_mmap_vm_close,
  724. .fault = filemap_fault,
  725. .map_pages = filemap_map_pages,
  726. .page_mkwrite = v9fs_vm_page_mkwrite,
  727. .remap_pages = generic_file_remap_pages,
  728. };
  729. const struct file_operations v9fs_cached_file_operations = {
  730. .llseek = generic_file_llseek,
  731. .read = v9fs_cached_file_read,
  732. .write = v9fs_cached_file_write,
  733. .read_iter = generic_file_read_iter,
  734. .write_iter = generic_file_write_iter,
  735. .open = v9fs_file_open,
  736. .release = v9fs_dir_release,
  737. .lock = v9fs_file_lock,
  738. .mmap = v9fs_file_mmap,
  739. .fsync = v9fs_file_fsync,
  740. };
  741. const struct file_operations v9fs_cached_file_operations_dotl = {
  742. .llseek = generic_file_llseek,
  743. .read = v9fs_cached_file_read,
  744. .write = v9fs_cached_file_write,
  745. .read_iter = generic_file_read_iter,
  746. .write_iter = generic_file_write_iter,
  747. .open = v9fs_file_open,
  748. .release = v9fs_dir_release,
  749. .lock = v9fs_file_lock_dotl,
  750. .flock = v9fs_file_flock_dotl,
  751. .mmap = v9fs_file_mmap,
  752. .fsync = v9fs_file_fsync_dotl,
  753. };
  754. const struct file_operations v9fs_file_operations = {
  755. .llseek = generic_file_llseek,
  756. .read = v9fs_file_read,
  757. .write = v9fs_file_write,
  758. .open = v9fs_file_open,
  759. .release = v9fs_dir_release,
  760. .lock = v9fs_file_lock,
  761. .mmap = generic_file_readonly_mmap,
  762. .fsync = v9fs_file_fsync,
  763. };
  764. const struct file_operations v9fs_file_operations_dotl = {
  765. .llseek = generic_file_llseek,
  766. .read = v9fs_file_read,
  767. .write = v9fs_file_write,
  768. .open = v9fs_file_open,
  769. .release = v9fs_dir_release,
  770. .lock = v9fs_file_lock_dotl,
  771. .flock = v9fs_file_flock_dotl,
  772. .mmap = generic_file_readonly_mmap,
  773. .fsync = v9fs_file_fsync_dotl,
  774. };
  775. const struct file_operations v9fs_mmap_file_operations = {
  776. .llseek = generic_file_llseek,
  777. .read = v9fs_mmap_file_read,
  778. .write = v9fs_mmap_file_write,
  779. .open = v9fs_file_open,
  780. .release = v9fs_dir_release,
  781. .lock = v9fs_file_lock,
  782. .mmap = v9fs_mmap_file_mmap,
  783. .fsync = v9fs_file_fsync,
  784. };
  785. const struct file_operations v9fs_mmap_file_operations_dotl = {
  786. .llseek = generic_file_llseek,
  787. .read = v9fs_mmap_file_read,
  788. .write = v9fs_mmap_file_write,
  789. .open = v9fs_file_open,
  790. .release = v9fs_dir_release,
  791. .lock = v9fs_file_lock_dotl,
  792. .flock = v9fs_file_flock_dotl,
  793. .mmap = v9fs_mmap_file_mmap,
  794. .fsync = v9fs_file_fsync_dotl,
  795. };