data.c 19 KB

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  1. /*
  2. * fs/f2fs/data.c
  3. *
  4. * Copyright (c) 2012 Samsung Electronics Co., Ltd.
  5. * http://www.samsung.com/
  6. *
  7. * This program is free software; you can redistribute it and/or modify
  8. * it under the terms of the GNU General Public License version 2 as
  9. * published by the Free Software Foundation.
  10. */
  11. #include <linux/fs.h>
  12. #include <linux/f2fs_fs.h>
  13. #include <linux/buffer_head.h>
  14. #include <linux/mpage.h>
  15. #include <linux/aio.h>
  16. #include <linux/writeback.h>
  17. #include <linux/backing-dev.h>
  18. #include <linux/blkdev.h>
  19. #include <linux/bio.h>
  20. #include <linux/prefetch.h>
  21. #include "f2fs.h"
  22. #include "node.h"
  23. #include "segment.h"
  24. #include <trace/events/f2fs.h>
  25. /*
  26. * Lock ordering for the change of data block address:
  27. * ->data_page
  28. * ->node_page
  29. * update block addresses in the node page
  30. */
  31. static void __set_data_blkaddr(struct dnode_of_data *dn, block_t new_addr)
  32. {
  33. struct f2fs_node *rn;
  34. __le32 *addr_array;
  35. struct page *node_page = dn->node_page;
  36. unsigned int ofs_in_node = dn->ofs_in_node;
  37. wait_on_page_writeback(node_page);
  38. rn = (struct f2fs_node *)page_address(node_page);
  39. /* Get physical address of data block */
  40. addr_array = blkaddr_in_node(rn);
  41. addr_array[ofs_in_node] = cpu_to_le32(new_addr);
  42. set_page_dirty(node_page);
  43. }
  44. int reserve_new_block(struct dnode_of_data *dn)
  45. {
  46. struct f2fs_sb_info *sbi = F2FS_SB(dn->inode->i_sb);
  47. if (is_inode_flag_set(F2FS_I(dn->inode), FI_NO_ALLOC))
  48. return -EPERM;
  49. if (!inc_valid_block_count(sbi, dn->inode, 1))
  50. return -ENOSPC;
  51. trace_f2fs_reserve_new_block(dn->inode, dn->nid, dn->ofs_in_node);
  52. __set_data_blkaddr(dn, NEW_ADDR);
  53. dn->data_blkaddr = NEW_ADDR;
  54. sync_inode_page(dn);
  55. return 0;
  56. }
  57. static int check_extent_cache(struct inode *inode, pgoff_t pgofs,
  58. struct buffer_head *bh_result)
  59. {
  60. struct f2fs_inode_info *fi = F2FS_I(inode);
  61. #ifdef CONFIG_F2FS_STAT_FS
  62. struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
  63. #endif
  64. pgoff_t start_fofs, end_fofs;
  65. block_t start_blkaddr;
  66. read_lock(&fi->ext.ext_lock);
  67. if (fi->ext.len == 0) {
  68. read_unlock(&fi->ext.ext_lock);
  69. return 0;
  70. }
  71. #ifdef CONFIG_F2FS_STAT_FS
  72. sbi->total_hit_ext++;
  73. #endif
  74. start_fofs = fi->ext.fofs;
  75. end_fofs = fi->ext.fofs + fi->ext.len - 1;
  76. start_blkaddr = fi->ext.blk_addr;
  77. if (pgofs >= start_fofs && pgofs <= end_fofs) {
  78. unsigned int blkbits = inode->i_sb->s_blocksize_bits;
  79. size_t count;
  80. clear_buffer_new(bh_result);
  81. map_bh(bh_result, inode->i_sb,
  82. start_blkaddr + pgofs - start_fofs);
  83. count = end_fofs - pgofs + 1;
  84. if (count < (UINT_MAX >> blkbits))
  85. bh_result->b_size = (count << blkbits);
  86. else
  87. bh_result->b_size = UINT_MAX;
  88. #ifdef CONFIG_F2FS_STAT_FS
  89. sbi->read_hit_ext++;
  90. #endif
  91. read_unlock(&fi->ext.ext_lock);
  92. return 1;
  93. }
  94. read_unlock(&fi->ext.ext_lock);
  95. return 0;
  96. }
  97. void update_extent_cache(block_t blk_addr, struct dnode_of_data *dn)
  98. {
  99. struct f2fs_inode_info *fi = F2FS_I(dn->inode);
  100. pgoff_t fofs, start_fofs, end_fofs;
  101. block_t start_blkaddr, end_blkaddr;
  102. BUG_ON(blk_addr == NEW_ADDR);
  103. fofs = start_bidx_of_node(ofs_of_node(dn->node_page)) + dn->ofs_in_node;
  104. /* Update the page address in the parent node */
  105. __set_data_blkaddr(dn, blk_addr);
  106. write_lock(&fi->ext.ext_lock);
  107. start_fofs = fi->ext.fofs;
  108. end_fofs = fi->ext.fofs + fi->ext.len - 1;
  109. start_blkaddr = fi->ext.blk_addr;
  110. end_blkaddr = fi->ext.blk_addr + fi->ext.len - 1;
  111. /* Drop and initialize the matched extent */
  112. if (fi->ext.len == 1 && fofs == start_fofs)
  113. fi->ext.len = 0;
  114. /* Initial extent */
  115. if (fi->ext.len == 0) {
  116. if (blk_addr != NULL_ADDR) {
  117. fi->ext.fofs = fofs;
  118. fi->ext.blk_addr = blk_addr;
  119. fi->ext.len = 1;
  120. }
  121. goto end_update;
  122. }
  123. /* Front merge */
  124. if (fofs == start_fofs - 1 && blk_addr == start_blkaddr - 1) {
  125. fi->ext.fofs--;
  126. fi->ext.blk_addr--;
  127. fi->ext.len++;
  128. goto end_update;
  129. }
  130. /* Back merge */
  131. if (fofs == end_fofs + 1 && blk_addr == end_blkaddr + 1) {
  132. fi->ext.len++;
  133. goto end_update;
  134. }
  135. /* Split the existing extent */
  136. if (fi->ext.len > 1 &&
  137. fofs >= start_fofs && fofs <= end_fofs) {
  138. if ((end_fofs - fofs) < (fi->ext.len >> 1)) {
  139. fi->ext.len = fofs - start_fofs;
  140. } else {
  141. fi->ext.fofs = fofs + 1;
  142. fi->ext.blk_addr = start_blkaddr +
  143. fofs - start_fofs + 1;
  144. fi->ext.len -= fofs - start_fofs + 1;
  145. }
  146. goto end_update;
  147. }
  148. write_unlock(&fi->ext.ext_lock);
  149. return;
  150. end_update:
  151. write_unlock(&fi->ext.ext_lock);
  152. sync_inode_page(dn);
  153. return;
  154. }
  155. struct page *find_data_page(struct inode *inode, pgoff_t index, bool sync)
  156. {
  157. struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
  158. struct address_space *mapping = inode->i_mapping;
  159. struct dnode_of_data dn;
  160. struct page *page;
  161. int err;
  162. page = find_get_page(mapping, index);
  163. if (page && PageUptodate(page))
  164. return page;
  165. f2fs_put_page(page, 0);
  166. set_new_dnode(&dn, inode, NULL, NULL, 0);
  167. err = get_dnode_of_data(&dn, index, LOOKUP_NODE);
  168. if (err)
  169. return ERR_PTR(err);
  170. f2fs_put_dnode(&dn);
  171. if (dn.data_blkaddr == NULL_ADDR)
  172. return ERR_PTR(-ENOENT);
  173. /* By fallocate(), there is no cached page, but with NEW_ADDR */
  174. if (dn.data_blkaddr == NEW_ADDR)
  175. return ERR_PTR(-EINVAL);
  176. page = grab_cache_page_write_begin(mapping, index, AOP_FLAG_NOFS);
  177. if (!page)
  178. return ERR_PTR(-ENOMEM);
  179. if (PageUptodate(page)) {
  180. unlock_page(page);
  181. return page;
  182. }
  183. err = f2fs_readpage(sbi, page, dn.data_blkaddr,
  184. sync ? READ_SYNC : READA);
  185. if (sync) {
  186. wait_on_page_locked(page);
  187. if (!PageUptodate(page)) {
  188. f2fs_put_page(page, 0);
  189. return ERR_PTR(-EIO);
  190. }
  191. }
  192. return page;
  193. }
  194. /*
  195. * If it tries to access a hole, return an error.
  196. * Because, the callers, functions in dir.c and GC, should be able to know
  197. * whether this page exists or not.
  198. */
  199. struct page *get_lock_data_page(struct inode *inode, pgoff_t index)
  200. {
  201. struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
  202. struct address_space *mapping = inode->i_mapping;
  203. struct dnode_of_data dn;
  204. struct page *page;
  205. int err;
  206. repeat:
  207. page = grab_cache_page_write_begin(mapping, index, AOP_FLAG_NOFS);
  208. if (!page)
  209. return ERR_PTR(-ENOMEM);
  210. set_new_dnode(&dn, inode, NULL, NULL, 0);
  211. err = get_dnode_of_data(&dn, index, LOOKUP_NODE);
  212. if (err) {
  213. f2fs_put_page(page, 1);
  214. return ERR_PTR(err);
  215. }
  216. f2fs_put_dnode(&dn);
  217. if (dn.data_blkaddr == NULL_ADDR) {
  218. f2fs_put_page(page, 1);
  219. return ERR_PTR(-ENOENT);
  220. }
  221. if (PageUptodate(page))
  222. return page;
  223. BUG_ON(dn.data_blkaddr == NEW_ADDR);
  224. BUG_ON(dn.data_blkaddr == NULL_ADDR);
  225. err = f2fs_readpage(sbi, page, dn.data_blkaddr, READ_SYNC);
  226. if (err)
  227. return ERR_PTR(err);
  228. lock_page(page);
  229. if (!PageUptodate(page)) {
  230. f2fs_put_page(page, 1);
  231. return ERR_PTR(-EIO);
  232. }
  233. if (page->mapping != mapping) {
  234. f2fs_put_page(page, 1);
  235. goto repeat;
  236. }
  237. return page;
  238. }
  239. /*
  240. * Caller ensures that this data page is never allocated.
  241. * A new zero-filled data page is allocated in the page cache.
  242. *
  243. * Also, caller should grab and release a mutex by calling mutex_lock_op() and
  244. * mutex_unlock_op().
  245. * Note that, npage is set only by make_empty_dir.
  246. */
  247. struct page *get_new_data_page(struct inode *inode,
  248. struct page *npage, pgoff_t index, bool new_i_size)
  249. {
  250. struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
  251. struct address_space *mapping = inode->i_mapping;
  252. struct page *page;
  253. struct dnode_of_data dn;
  254. int err;
  255. set_new_dnode(&dn, inode, npage, npage, 0);
  256. err = get_dnode_of_data(&dn, index, ALLOC_NODE);
  257. if (err)
  258. return ERR_PTR(err);
  259. if (dn.data_blkaddr == NULL_ADDR) {
  260. if (reserve_new_block(&dn)) {
  261. if (!npage)
  262. f2fs_put_dnode(&dn);
  263. return ERR_PTR(-ENOSPC);
  264. }
  265. }
  266. if (!npage)
  267. f2fs_put_dnode(&dn);
  268. repeat:
  269. page = grab_cache_page(mapping, index);
  270. if (!page)
  271. return ERR_PTR(-ENOMEM);
  272. if (PageUptodate(page))
  273. return page;
  274. if (dn.data_blkaddr == NEW_ADDR) {
  275. zero_user_segment(page, 0, PAGE_CACHE_SIZE);
  276. SetPageUptodate(page);
  277. } else {
  278. err = f2fs_readpage(sbi, page, dn.data_blkaddr, READ_SYNC);
  279. if (err)
  280. return ERR_PTR(err);
  281. lock_page(page);
  282. if (!PageUptodate(page)) {
  283. f2fs_put_page(page, 1);
  284. return ERR_PTR(-EIO);
  285. }
  286. if (page->mapping != mapping) {
  287. f2fs_put_page(page, 1);
  288. goto repeat;
  289. }
  290. }
  291. if (new_i_size &&
  292. i_size_read(inode) < ((index + 1) << PAGE_CACHE_SHIFT)) {
  293. i_size_write(inode, ((index + 1) << PAGE_CACHE_SHIFT));
  294. /* Only the directory inode sets new_i_size */
  295. set_inode_flag(F2FS_I(inode), FI_UPDATE_DIR);
  296. mark_inode_dirty_sync(inode);
  297. }
  298. return page;
  299. }
  300. static void read_end_io(struct bio *bio, int err)
  301. {
  302. const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
  303. struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
  304. do {
  305. struct page *page = bvec->bv_page;
  306. if (--bvec >= bio->bi_io_vec)
  307. prefetchw(&bvec->bv_page->flags);
  308. if (uptodate) {
  309. SetPageUptodate(page);
  310. } else {
  311. ClearPageUptodate(page);
  312. SetPageError(page);
  313. }
  314. unlock_page(page);
  315. } while (bvec >= bio->bi_io_vec);
  316. kfree(bio->bi_private);
  317. bio_put(bio);
  318. }
  319. /*
  320. * Fill the locked page with data located in the block address.
  321. * Return unlocked page.
  322. */
  323. int f2fs_readpage(struct f2fs_sb_info *sbi, struct page *page,
  324. block_t blk_addr, int type)
  325. {
  326. struct block_device *bdev = sbi->sb->s_bdev;
  327. struct bio *bio;
  328. trace_f2fs_readpage(page, blk_addr, type);
  329. down_read(&sbi->bio_sem);
  330. /* Allocate a new bio */
  331. bio = f2fs_bio_alloc(bdev, 1);
  332. /* Initialize the bio */
  333. bio->bi_sector = SECTOR_FROM_BLOCK(sbi, blk_addr);
  334. bio->bi_end_io = read_end_io;
  335. if (bio_add_page(bio, page, PAGE_CACHE_SIZE, 0) < PAGE_CACHE_SIZE) {
  336. kfree(bio->bi_private);
  337. bio_put(bio);
  338. up_read(&sbi->bio_sem);
  339. f2fs_put_page(page, 1);
  340. return -EFAULT;
  341. }
  342. submit_bio(type, bio);
  343. up_read(&sbi->bio_sem);
  344. return 0;
  345. }
  346. /*
  347. * This function should be used by the data read flow only where it
  348. * does not check the "create" flag that indicates block allocation.
  349. * The reason for this special functionality is to exploit VFS readahead
  350. * mechanism.
  351. */
  352. static int get_data_block_ro(struct inode *inode, sector_t iblock,
  353. struct buffer_head *bh_result, int create)
  354. {
  355. unsigned int blkbits = inode->i_sb->s_blocksize_bits;
  356. unsigned maxblocks = bh_result->b_size >> blkbits;
  357. struct dnode_of_data dn;
  358. pgoff_t pgofs;
  359. int err;
  360. /* Get the page offset from the block offset(iblock) */
  361. pgofs = (pgoff_t)(iblock >> (PAGE_CACHE_SHIFT - blkbits));
  362. if (check_extent_cache(inode, pgofs, bh_result)) {
  363. trace_f2fs_get_data_block(inode, iblock, bh_result, 0);
  364. return 0;
  365. }
  366. /* When reading holes, we need its node page */
  367. set_new_dnode(&dn, inode, NULL, NULL, 0);
  368. err = get_dnode_of_data(&dn, pgofs, LOOKUP_NODE_RA);
  369. if (err) {
  370. trace_f2fs_get_data_block(inode, iblock, bh_result, err);
  371. return (err == -ENOENT) ? 0 : err;
  372. }
  373. /* It does not support data allocation */
  374. BUG_ON(create);
  375. if (dn.data_blkaddr != NEW_ADDR && dn.data_blkaddr != NULL_ADDR) {
  376. int i;
  377. unsigned int end_offset;
  378. end_offset = IS_INODE(dn.node_page) ?
  379. ADDRS_PER_INODE :
  380. ADDRS_PER_BLOCK;
  381. clear_buffer_new(bh_result);
  382. /* Give more consecutive addresses for the read ahead */
  383. for (i = 0; i < end_offset - dn.ofs_in_node; i++)
  384. if (((datablock_addr(dn.node_page,
  385. dn.ofs_in_node + i))
  386. != (dn.data_blkaddr + i)) || maxblocks == i)
  387. break;
  388. map_bh(bh_result, inode->i_sb, dn.data_blkaddr);
  389. bh_result->b_size = (i << blkbits);
  390. }
  391. f2fs_put_dnode(&dn);
  392. trace_f2fs_get_data_block(inode, iblock, bh_result, 0);
  393. return 0;
  394. }
  395. static int f2fs_read_data_page(struct file *file, struct page *page)
  396. {
  397. return mpage_readpage(page, get_data_block_ro);
  398. }
  399. static int f2fs_read_data_pages(struct file *file,
  400. struct address_space *mapping,
  401. struct list_head *pages, unsigned nr_pages)
  402. {
  403. return mpage_readpages(mapping, pages, nr_pages, get_data_block_ro);
  404. }
  405. int do_write_data_page(struct page *page)
  406. {
  407. struct inode *inode = page->mapping->host;
  408. block_t old_blk_addr, new_blk_addr;
  409. struct dnode_of_data dn;
  410. int err = 0;
  411. set_new_dnode(&dn, inode, NULL, NULL, 0);
  412. err = get_dnode_of_data(&dn, page->index, LOOKUP_NODE);
  413. if (err)
  414. return err;
  415. old_blk_addr = dn.data_blkaddr;
  416. /* This page is already truncated */
  417. if (old_blk_addr == NULL_ADDR)
  418. goto out_writepage;
  419. set_page_writeback(page);
  420. /*
  421. * If current allocation needs SSR,
  422. * it had better in-place writes for updated data.
  423. */
  424. if (unlikely(old_blk_addr != NEW_ADDR &&
  425. !is_cold_data(page) &&
  426. need_inplace_update(inode))) {
  427. rewrite_data_page(F2FS_SB(inode->i_sb), page,
  428. old_blk_addr);
  429. } else {
  430. write_data_page(inode, page, &dn,
  431. old_blk_addr, &new_blk_addr);
  432. update_extent_cache(new_blk_addr, &dn);
  433. }
  434. out_writepage:
  435. f2fs_put_dnode(&dn);
  436. return err;
  437. }
  438. static int f2fs_write_data_page(struct page *page,
  439. struct writeback_control *wbc)
  440. {
  441. struct inode *inode = page->mapping->host;
  442. struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
  443. loff_t i_size = i_size_read(inode);
  444. const pgoff_t end_index = ((unsigned long long) i_size)
  445. >> PAGE_CACHE_SHIFT;
  446. unsigned offset;
  447. bool need_balance_fs = false;
  448. int err = 0;
  449. if (page->index < end_index)
  450. goto write;
  451. /*
  452. * If the offset is out-of-range of file size,
  453. * this page does not have to be written to disk.
  454. */
  455. offset = i_size & (PAGE_CACHE_SIZE - 1);
  456. if ((page->index >= end_index + 1) || !offset) {
  457. if (S_ISDIR(inode->i_mode)) {
  458. dec_page_count(sbi, F2FS_DIRTY_DENTS);
  459. inode_dec_dirty_dents(inode);
  460. }
  461. goto out;
  462. }
  463. zero_user_segment(page, offset, PAGE_CACHE_SIZE);
  464. write:
  465. if (sbi->por_doing) {
  466. err = AOP_WRITEPAGE_ACTIVATE;
  467. goto redirty_out;
  468. }
  469. /* Dentry blocks are controlled by checkpoint */
  470. if (S_ISDIR(inode->i_mode)) {
  471. dec_page_count(sbi, F2FS_DIRTY_DENTS);
  472. inode_dec_dirty_dents(inode);
  473. err = do_write_data_page(page);
  474. } else {
  475. int ilock = mutex_lock_op(sbi);
  476. err = do_write_data_page(page);
  477. mutex_unlock_op(sbi, ilock);
  478. need_balance_fs = true;
  479. }
  480. if (err == -ENOENT)
  481. goto out;
  482. else if (err)
  483. goto redirty_out;
  484. if (wbc->for_reclaim)
  485. f2fs_submit_bio(sbi, DATA, true);
  486. clear_cold_data(page);
  487. out:
  488. unlock_page(page);
  489. if (need_balance_fs)
  490. f2fs_balance_fs(sbi);
  491. return 0;
  492. redirty_out:
  493. wbc->pages_skipped++;
  494. set_page_dirty(page);
  495. return err;
  496. }
  497. #define MAX_DESIRED_PAGES_WP 4096
  498. static int __f2fs_writepage(struct page *page, struct writeback_control *wbc,
  499. void *data)
  500. {
  501. struct address_space *mapping = data;
  502. int ret = mapping->a_ops->writepage(page, wbc);
  503. mapping_set_error(mapping, ret);
  504. return ret;
  505. }
  506. static int f2fs_write_data_pages(struct address_space *mapping,
  507. struct writeback_control *wbc)
  508. {
  509. struct inode *inode = mapping->host;
  510. struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
  511. bool locked = false;
  512. int ret;
  513. long excess_nrtw = 0, desired_nrtw;
  514. /* deal with chardevs and other special file */
  515. if (!mapping->a_ops->writepage)
  516. return 0;
  517. if (wbc->nr_to_write < MAX_DESIRED_PAGES_WP) {
  518. desired_nrtw = MAX_DESIRED_PAGES_WP;
  519. excess_nrtw = desired_nrtw - wbc->nr_to_write;
  520. wbc->nr_to_write = desired_nrtw;
  521. }
  522. if (!S_ISDIR(inode->i_mode)) {
  523. mutex_lock(&sbi->writepages);
  524. locked = true;
  525. }
  526. ret = write_cache_pages(mapping, wbc, __f2fs_writepage, mapping);
  527. if (locked)
  528. mutex_unlock(&sbi->writepages);
  529. f2fs_submit_bio(sbi, DATA, (wbc->sync_mode == WB_SYNC_ALL));
  530. remove_dirty_dir_inode(inode);
  531. wbc->nr_to_write -= excess_nrtw;
  532. return ret;
  533. }
  534. static int f2fs_write_begin(struct file *file, struct address_space *mapping,
  535. loff_t pos, unsigned len, unsigned flags,
  536. struct page **pagep, void **fsdata)
  537. {
  538. struct inode *inode = mapping->host;
  539. struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
  540. struct page *page;
  541. pgoff_t index = ((unsigned long long) pos) >> PAGE_CACHE_SHIFT;
  542. struct dnode_of_data dn;
  543. int err = 0;
  544. int ilock;
  545. /* for nobh_write_end */
  546. *fsdata = NULL;
  547. f2fs_balance_fs(sbi);
  548. repeat:
  549. page = grab_cache_page_write_begin(mapping, index, flags);
  550. if (!page)
  551. return -ENOMEM;
  552. *pagep = page;
  553. ilock = mutex_lock_op(sbi);
  554. set_new_dnode(&dn, inode, NULL, NULL, 0);
  555. err = get_dnode_of_data(&dn, index, ALLOC_NODE);
  556. if (err)
  557. goto err;
  558. if (dn.data_blkaddr == NULL_ADDR)
  559. err = reserve_new_block(&dn);
  560. f2fs_put_dnode(&dn);
  561. if (err)
  562. goto err;
  563. mutex_unlock_op(sbi, ilock);
  564. if ((len == PAGE_CACHE_SIZE) || PageUptodate(page))
  565. return 0;
  566. if ((pos & PAGE_CACHE_MASK) >= i_size_read(inode)) {
  567. unsigned start = pos & (PAGE_CACHE_SIZE - 1);
  568. unsigned end = start + len;
  569. /* Reading beyond i_size is simple: memset to zero */
  570. zero_user_segments(page, 0, start, end, PAGE_CACHE_SIZE);
  571. goto out;
  572. }
  573. if (dn.data_blkaddr == NEW_ADDR) {
  574. zero_user_segment(page, 0, PAGE_CACHE_SIZE);
  575. } else {
  576. err = f2fs_readpage(sbi, page, dn.data_blkaddr, READ_SYNC);
  577. if (err)
  578. return err;
  579. lock_page(page);
  580. if (!PageUptodate(page)) {
  581. f2fs_put_page(page, 1);
  582. return -EIO;
  583. }
  584. if (page->mapping != mapping) {
  585. f2fs_put_page(page, 1);
  586. goto repeat;
  587. }
  588. }
  589. out:
  590. SetPageUptodate(page);
  591. clear_cold_data(page);
  592. return 0;
  593. err:
  594. mutex_unlock_op(sbi, ilock);
  595. f2fs_put_page(page, 1);
  596. return err;
  597. }
  598. static int f2fs_write_end(struct file *file,
  599. struct address_space *mapping,
  600. loff_t pos, unsigned len, unsigned copied,
  601. struct page *page, void *fsdata)
  602. {
  603. struct inode *inode = page->mapping->host;
  604. SetPageUptodate(page);
  605. set_page_dirty(page);
  606. if (pos + copied > i_size_read(inode)) {
  607. i_size_write(inode, pos + copied);
  608. mark_inode_dirty(inode);
  609. update_inode_page(inode);
  610. }
  611. unlock_page(page);
  612. page_cache_release(page);
  613. return copied;
  614. }
  615. static ssize_t f2fs_direct_IO(int rw, struct kiocb *iocb,
  616. const struct iovec *iov, loff_t offset, unsigned long nr_segs)
  617. {
  618. struct file *file = iocb->ki_filp;
  619. struct inode *inode = file->f_mapping->host;
  620. if (rw == WRITE)
  621. return 0;
  622. /* Needs synchronization with the cleaner */
  623. return blockdev_direct_IO(rw, iocb, inode, iov, offset, nr_segs,
  624. get_data_block_ro);
  625. }
  626. static void f2fs_invalidate_data_page(struct page *page, unsigned int offset,
  627. unsigned int length)
  628. {
  629. struct inode *inode = page->mapping->host;
  630. struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
  631. if (S_ISDIR(inode->i_mode) && PageDirty(page)) {
  632. dec_page_count(sbi, F2FS_DIRTY_DENTS);
  633. inode_dec_dirty_dents(inode);
  634. }
  635. ClearPagePrivate(page);
  636. }
  637. static int f2fs_release_data_page(struct page *page, gfp_t wait)
  638. {
  639. ClearPagePrivate(page);
  640. return 1;
  641. }
  642. static int f2fs_set_data_page_dirty(struct page *page)
  643. {
  644. struct address_space *mapping = page->mapping;
  645. struct inode *inode = mapping->host;
  646. SetPageUptodate(page);
  647. if (!PageDirty(page)) {
  648. __set_page_dirty_nobuffers(page);
  649. set_dirty_dir_page(inode, page);
  650. return 1;
  651. }
  652. return 0;
  653. }
  654. static sector_t f2fs_bmap(struct address_space *mapping, sector_t block)
  655. {
  656. return generic_block_bmap(mapping, block, get_data_block_ro);
  657. }
  658. const struct address_space_operations f2fs_dblock_aops = {
  659. .readpage = f2fs_read_data_page,
  660. .readpages = f2fs_read_data_pages,
  661. .writepage = f2fs_write_data_page,
  662. .writepages = f2fs_write_data_pages,
  663. .write_begin = f2fs_write_begin,
  664. .write_end = f2fs_write_end,
  665. .set_page_dirty = f2fs_set_data_page_dirty,
  666. .invalidatepage = f2fs_invalidate_data_page,
  667. .releasepage = f2fs_release_data_page,
  668. .direct_IO = f2fs_direct_IO,
  669. .bmap = f2fs_bmap,
  670. };