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. f2fs_wait_on_page_writeback(node_page, NODE, false);
  38. rn = F2FS_NODE(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), fi) +
  104. dn->ofs_in_node;
  105. /* Update the page address in the parent node */
  106. __set_data_blkaddr(dn, blk_addr);
  107. write_lock(&fi->ext.ext_lock);
  108. start_fofs = fi->ext.fofs;
  109. end_fofs = fi->ext.fofs + fi->ext.len - 1;
  110. start_blkaddr = fi->ext.blk_addr;
  111. end_blkaddr = fi->ext.blk_addr + fi->ext.len - 1;
  112. /* Drop and initialize the matched extent */
  113. if (fi->ext.len == 1 && fofs == start_fofs)
  114. fi->ext.len = 0;
  115. /* Initial extent */
  116. if (fi->ext.len == 0) {
  117. if (blk_addr != NULL_ADDR) {
  118. fi->ext.fofs = fofs;
  119. fi->ext.blk_addr = blk_addr;
  120. fi->ext.len = 1;
  121. }
  122. goto end_update;
  123. }
  124. /* Front merge */
  125. if (fofs == start_fofs - 1 && blk_addr == start_blkaddr - 1) {
  126. fi->ext.fofs--;
  127. fi->ext.blk_addr--;
  128. fi->ext.len++;
  129. goto end_update;
  130. }
  131. /* Back merge */
  132. if (fofs == end_fofs + 1 && blk_addr == end_blkaddr + 1) {
  133. fi->ext.len++;
  134. goto end_update;
  135. }
  136. /* Split the existing extent */
  137. if (fi->ext.len > 1 &&
  138. fofs >= start_fofs && fofs <= end_fofs) {
  139. if ((end_fofs - fofs) < (fi->ext.len >> 1)) {
  140. fi->ext.len = fofs - start_fofs;
  141. } else {
  142. fi->ext.fofs = fofs + 1;
  143. fi->ext.blk_addr = start_blkaddr +
  144. fofs - start_fofs + 1;
  145. fi->ext.len -= fofs - start_fofs + 1;
  146. }
  147. goto end_update;
  148. }
  149. write_unlock(&fi->ext.ext_lock);
  150. return;
  151. end_update:
  152. write_unlock(&fi->ext.ext_lock);
  153. sync_inode_page(dn);
  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. /*
  224. * A new dentry page is allocated but not able to be written, since its
  225. * new inode page couldn't be allocated due to -ENOSPC.
  226. * In such the case, its blkaddr can be remained as NEW_ADDR.
  227. * see, f2fs_add_link -> get_new_data_page -> init_inode_metadata.
  228. */
  229. if (dn.data_blkaddr == NEW_ADDR) {
  230. zero_user_segment(page, 0, PAGE_CACHE_SIZE);
  231. SetPageUptodate(page);
  232. return page;
  233. }
  234. err = f2fs_readpage(sbi, page, dn.data_blkaddr, READ_SYNC);
  235. if (err)
  236. return ERR_PTR(err);
  237. lock_page(page);
  238. if (!PageUptodate(page)) {
  239. f2fs_put_page(page, 1);
  240. return ERR_PTR(-EIO);
  241. }
  242. if (page->mapping != mapping) {
  243. f2fs_put_page(page, 1);
  244. goto repeat;
  245. }
  246. return page;
  247. }
  248. /*
  249. * Caller ensures that this data page is never allocated.
  250. * A new zero-filled data page is allocated in the page cache.
  251. *
  252. * Also, caller should grab and release a mutex by calling mutex_lock_op() and
  253. * mutex_unlock_op().
  254. * Note that, npage is set only by make_empty_dir.
  255. */
  256. struct page *get_new_data_page(struct inode *inode,
  257. struct page *npage, pgoff_t index, bool new_i_size)
  258. {
  259. struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
  260. struct address_space *mapping = inode->i_mapping;
  261. struct page *page;
  262. struct dnode_of_data dn;
  263. int err;
  264. set_new_dnode(&dn, inode, npage, npage, 0);
  265. err = get_dnode_of_data(&dn, index, ALLOC_NODE);
  266. if (err)
  267. return ERR_PTR(err);
  268. if (dn.data_blkaddr == NULL_ADDR) {
  269. if (reserve_new_block(&dn)) {
  270. if (!npage)
  271. f2fs_put_dnode(&dn);
  272. return ERR_PTR(-ENOSPC);
  273. }
  274. }
  275. if (!npage)
  276. f2fs_put_dnode(&dn);
  277. repeat:
  278. page = grab_cache_page(mapping, index);
  279. if (!page)
  280. return ERR_PTR(-ENOMEM);
  281. if (PageUptodate(page))
  282. return page;
  283. if (dn.data_blkaddr == NEW_ADDR) {
  284. zero_user_segment(page, 0, PAGE_CACHE_SIZE);
  285. SetPageUptodate(page);
  286. } else {
  287. err = f2fs_readpage(sbi, page, dn.data_blkaddr, READ_SYNC);
  288. if (err)
  289. return ERR_PTR(err);
  290. lock_page(page);
  291. if (!PageUptodate(page)) {
  292. f2fs_put_page(page, 1);
  293. return ERR_PTR(-EIO);
  294. }
  295. if (page->mapping != mapping) {
  296. f2fs_put_page(page, 1);
  297. goto repeat;
  298. }
  299. }
  300. if (new_i_size &&
  301. i_size_read(inode) < ((index + 1) << PAGE_CACHE_SHIFT)) {
  302. i_size_write(inode, ((index + 1) << PAGE_CACHE_SHIFT));
  303. /* Only the directory inode sets new_i_size */
  304. set_inode_flag(F2FS_I(inode), FI_UPDATE_DIR);
  305. mark_inode_dirty_sync(inode);
  306. }
  307. return page;
  308. }
  309. static void read_end_io(struct bio *bio, int err)
  310. {
  311. const int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
  312. struct bio_vec *bvec = bio->bi_io_vec + bio->bi_vcnt - 1;
  313. do {
  314. struct page *page = bvec->bv_page;
  315. if (--bvec >= bio->bi_io_vec)
  316. prefetchw(&bvec->bv_page->flags);
  317. if (uptodate) {
  318. SetPageUptodate(page);
  319. } else {
  320. ClearPageUptodate(page);
  321. SetPageError(page);
  322. }
  323. unlock_page(page);
  324. } while (bvec >= bio->bi_io_vec);
  325. bio_put(bio);
  326. }
  327. /*
  328. * Fill the locked page with data located in the block address.
  329. * Return unlocked page.
  330. */
  331. int f2fs_readpage(struct f2fs_sb_info *sbi, struct page *page,
  332. block_t blk_addr, int type)
  333. {
  334. struct block_device *bdev = sbi->sb->s_bdev;
  335. struct bio *bio;
  336. trace_f2fs_readpage(page, blk_addr, type);
  337. down_read(&sbi->bio_sem);
  338. /* Allocate a new bio */
  339. bio = f2fs_bio_alloc(bdev, 1);
  340. /* Initialize the bio */
  341. bio->bi_sector = SECTOR_FROM_BLOCK(sbi, blk_addr);
  342. bio->bi_end_io = read_end_io;
  343. if (bio_add_page(bio, page, PAGE_CACHE_SIZE, 0) < PAGE_CACHE_SIZE) {
  344. bio_put(bio);
  345. up_read(&sbi->bio_sem);
  346. f2fs_put_page(page, 1);
  347. return -EFAULT;
  348. }
  349. submit_bio(type, bio);
  350. up_read(&sbi->bio_sem);
  351. return 0;
  352. }
  353. /*
  354. * This function should be used by the data read flow only where it
  355. * does not check the "create" flag that indicates block allocation.
  356. * The reason for this special functionality is to exploit VFS readahead
  357. * mechanism.
  358. */
  359. static int get_data_block_ro(struct inode *inode, sector_t iblock,
  360. struct buffer_head *bh_result, int create)
  361. {
  362. unsigned int blkbits = inode->i_sb->s_blocksize_bits;
  363. unsigned maxblocks = bh_result->b_size >> blkbits;
  364. struct dnode_of_data dn;
  365. pgoff_t pgofs;
  366. int err;
  367. /* Get the page offset from the block offset(iblock) */
  368. pgofs = (pgoff_t)(iblock >> (PAGE_CACHE_SHIFT - blkbits));
  369. if (check_extent_cache(inode, pgofs, bh_result)) {
  370. trace_f2fs_get_data_block(inode, iblock, bh_result, 0);
  371. return 0;
  372. }
  373. /* When reading holes, we need its node page */
  374. set_new_dnode(&dn, inode, NULL, NULL, 0);
  375. err = get_dnode_of_data(&dn, pgofs, LOOKUP_NODE_RA);
  376. if (err) {
  377. trace_f2fs_get_data_block(inode, iblock, bh_result, err);
  378. return (err == -ENOENT) ? 0 : err;
  379. }
  380. /* It does not support data allocation */
  381. BUG_ON(create);
  382. if (dn.data_blkaddr != NEW_ADDR && dn.data_blkaddr != NULL_ADDR) {
  383. int i;
  384. unsigned int end_offset;
  385. end_offset = IS_INODE(dn.node_page) ?
  386. ADDRS_PER_INODE(F2FS_I(inode)) :
  387. ADDRS_PER_BLOCK;
  388. clear_buffer_new(bh_result);
  389. /* Give more consecutive addresses for the read ahead */
  390. for (i = 0; i < end_offset - dn.ofs_in_node; i++)
  391. if (((datablock_addr(dn.node_page,
  392. dn.ofs_in_node + i))
  393. != (dn.data_blkaddr + i)) || maxblocks == i)
  394. break;
  395. map_bh(bh_result, inode->i_sb, dn.data_blkaddr);
  396. bh_result->b_size = (i << blkbits);
  397. }
  398. f2fs_put_dnode(&dn);
  399. trace_f2fs_get_data_block(inode, iblock, bh_result, 0);
  400. return 0;
  401. }
  402. static int f2fs_read_data_page(struct file *file, struct page *page)
  403. {
  404. return mpage_readpage(page, get_data_block_ro);
  405. }
  406. static int f2fs_read_data_pages(struct file *file,
  407. struct address_space *mapping,
  408. struct list_head *pages, unsigned nr_pages)
  409. {
  410. return mpage_readpages(mapping, pages, nr_pages, get_data_block_ro);
  411. }
  412. int do_write_data_page(struct page *page)
  413. {
  414. struct inode *inode = page->mapping->host;
  415. block_t old_blk_addr, new_blk_addr;
  416. struct dnode_of_data dn;
  417. int err = 0;
  418. set_new_dnode(&dn, inode, NULL, NULL, 0);
  419. err = get_dnode_of_data(&dn, page->index, LOOKUP_NODE);
  420. if (err)
  421. return err;
  422. old_blk_addr = dn.data_blkaddr;
  423. /* This page is already truncated */
  424. if (old_blk_addr == NULL_ADDR)
  425. goto out_writepage;
  426. set_page_writeback(page);
  427. /*
  428. * If current allocation needs SSR,
  429. * it had better in-place writes for updated data.
  430. */
  431. if (unlikely(old_blk_addr != NEW_ADDR &&
  432. !is_cold_data(page) &&
  433. need_inplace_update(inode))) {
  434. rewrite_data_page(F2FS_SB(inode->i_sb), page,
  435. old_blk_addr);
  436. } else {
  437. write_data_page(inode, page, &dn,
  438. old_blk_addr, &new_blk_addr);
  439. update_extent_cache(new_blk_addr, &dn);
  440. }
  441. out_writepage:
  442. f2fs_put_dnode(&dn);
  443. return err;
  444. }
  445. static int f2fs_write_data_page(struct page *page,
  446. struct writeback_control *wbc)
  447. {
  448. struct inode *inode = page->mapping->host;
  449. struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
  450. loff_t i_size = i_size_read(inode);
  451. const pgoff_t end_index = ((unsigned long long) i_size)
  452. >> PAGE_CACHE_SHIFT;
  453. unsigned offset;
  454. bool need_balance_fs = false;
  455. int err = 0;
  456. if (page->index < end_index)
  457. goto write;
  458. /*
  459. * If the offset is out-of-range of file size,
  460. * this page does not have to be written to disk.
  461. */
  462. offset = i_size & (PAGE_CACHE_SIZE - 1);
  463. if ((page->index >= end_index + 1) || !offset) {
  464. if (S_ISDIR(inode->i_mode)) {
  465. dec_page_count(sbi, F2FS_DIRTY_DENTS);
  466. inode_dec_dirty_dents(inode);
  467. }
  468. goto out;
  469. }
  470. zero_user_segment(page, offset, PAGE_CACHE_SIZE);
  471. write:
  472. if (sbi->por_doing) {
  473. err = AOP_WRITEPAGE_ACTIVATE;
  474. goto redirty_out;
  475. }
  476. /* Dentry blocks are controlled by checkpoint */
  477. if (S_ISDIR(inode->i_mode)) {
  478. dec_page_count(sbi, F2FS_DIRTY_DENTS);
  479. inode_dec_dirty_dents(inode);
  480. err = do_write_data_page(page);
  481. } else {
  482. int ilock = mutex_lock_op(sbi);
  483. err = do_write_data_page(page);
  484. mutex_unlock_op(sbi, ilock);
  485. need_balance_fs = true;
  486. }
  487. if (err == -ENOENT)
  488. goto out;
  489. else if (err)
  490. goto redirty_out;
  491. if (wbc->for_reclaim)
  492. f2fs_submit_bio(sbi, DATA, true);
  493. clear_cold_data(page);
  494. out:
  495. unlock_page(page);
  496. if (need_balance_fs)
  497. f2fs_balance_fs(sbi);
  498. return 0;
  499. redirty_out:
  500. wbc->pages_skipped++;
  501. set_page_dirty(page);
  502. return err;
  503. }
  504. #define MAX_DESIRED_PAGES_WP 4096
  505. static int __f2fs_writepage(struct page *page, struct writeback_control *wbc,
  506. void *data)
  507. {
  508. struct address_space *mapping = data;
  509. int ret = mapping->a_ops->writepage(page, wbc);
  510. mapping_set_error(mapping, ret);
  511. return ret;
  512. }
  513. static int f2fs_write_data_pages(struct address_space *mapping,
  514. struct writeback_control *wbc)
  515. {
  516. struct inode *inode = mapping->host;
  517. struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
  518. bool locked = false;
  519. int ret;
  520. long excess_nrtw = 0, desired_nrtw;
  521. /* deal with chardevs and other special file */
  522. if (!mapping->a_ops->writepage)
  523. return 0;
  524. if (wbc->nr_to_write < MAX_DESIRED_PAGES_WP) {
  525. desired_nrtw = MAX_DESIRED_PAGES_WP;
  526. excess_nrtw = desired_nrtw - wbc->nr_to_write;
  527. wbc->nr_to_write = desired_nrtw;
  528. }
  529. if (!S_ISDIR(inode->i_mode)) {
  530. mutex_lock(&sbi->writepages);
  531. locked = true;
  532. }
  533. ret = write_cache_pages(mapping, wbc, __f2fs_writepage, mapping);
  534. if (locked)
  535. mutex_unlock(&sbi->writepages);
  536. f2fs_submit_bio(sbi, DATA, (wbc->sync_mode == WB_SYNC_ALL));
  537. remove_dirty_dir_inode(inode);
  538. wbc->nr_to_write -= excess_nrtw;
  539. return ret;
  540. }
  541. static int f2fs_write_begin(struct file *file, struct address_space *mapping,
  542. loff_t pos, unsigned len, unsigned flags,
  543. struct page **pagep, void **fsdata)
  544. {
  545. struct inode *inode = mapping->host;
  546. struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
  547. struct page *page;
  548. pgoff_t index = ((unsigned long long) pos) >> PAGE_CACHE_SHIFT;
  549. struct dnode_of_data dn;
  550. int err = 0;
  551. int ilock;
  552. f2fs_balance_fs(sbi);
  553. repeat:
  554. page = grab_cache_page_write_begin(mapping, index, flags);
  555. if (!page)
  556. return -ENOMEM;
  557. *pagep = page;
  558. ilock = mutex_lock_op(sbi);
  559. set_new_dnode(&dn, inode, NULL, NULL, 0);
  560. err = get_dnode_of_data(&dn, index, ALLOC_NODE);
  561. if (err)
  562. goto err;
  563. if (dn.data_blkaddr == NULL_ADDR)
  564. err = reserve_new_block(&dn);
  565. f2fs_put_dnode(&dn);
  566. if (err)
  567. goto err;
  568. mutex_unlock_op(sbi, ilock);
  569. if ((len == PAGE_CACHE_SIZE) || PageUptodate(page))
  570. return 0;
  571. if ((pos & PAGE_CACHE_MASK) >= i_size_read(inode)) {
  572. unsigned start = pos & (PAGE_CACHE_SIZE - 1);
  573. unsigned end = start + len;
  574. /* Reading beyond i_size is simple: memset to zero */
  575. zero_user_segments(page, 0, start, end, PAGE_CACHE_SIZE);
  576. goto out;
  577. }
  578. if (dn.data_blkaddr == NEW_ADDR) {
  579. zero_user_segment(page, 0, PAGE_CACHE_SIZE);
  580. } else {
  581. err = f2fs_readpage(sbi, page, dn.data_blkaddr, READ_SYNC);
  582. if (err)
  583. return err;
  584. lock_page(page);
  585. if (!PageUptodate(page)) {
  586. f2fs_put_page(page, 1);
  587. return -EIO;
  588. }
  589. if (page->mapping != mapping) {
  590. f2fs_put_page(page, 1);
  591. goto repeat;
  592. }
  593. }
  594. out:
  595. SetPageUptodate(page);
  596. clear_cold_data(page);
  597. return 0;
  598. err:
  599. mutex_unlock_op(sbi, ilock);
  600. f2fs_put_page(page, 1);
  601. return err;
  602. }
  603. static int f2fs_write_end(struct file *file,
  604. struct address_space *mapping,
  605. loff_t pos, unsigned len, unsigned copied,
  606. struct page *page, void *fsdata)
  607. {
  608. struct inode *inode = page->mapping->host;
  609. SetPageUptodate(page);
  610. set_page_dirty(page);
  611. if (pos + copied > i_size_read(inode)) {
  612. i_size_write(inode, pos + copied);
  613. mark_inode_dirty(inode);
  614. update_inode_page(inode);
  615. }
  616. unlock_page(page);
  617. page_cache_release(page);
  618. return copied;
  619. }
  620. static ssize_t f2fs_direct_IO(int rw, struct kiocb *iocb,
  621. const struct iovec *iov, loff_t offset, unsigned long nr_segs)
  622. {
  623. struct file *file = iocb->ki_filp;
  624. struct inode *inode = file->f_mapping->host;
  625. if (rw == WRITE)
  626. return 0;
  627. /* Needs synchronization with the cleaner */
  628. return blockdev_direct_IO(rw, iocb, inode, iov, offset, nr_segs,
  629. get_data_block_ro);
  630. }
  631. static void f2fs_invalidate_data_page(struct page *page, unsigned int offset,
  632. unsigned int length)
  633. {
  634. struct inode *inode = page->mapping->host;
  635. struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
  636. if (S_ISDIR(inode->i_mode) && PageDirty(page)) {
  637. dec_page_count(sbi, F2FS_DIRTY_DENTS);
  638. inode_dec_dirty_dents(inode);
  639. }
  640. ClearPagePrivate(page);
  641. }
  642. static int f2fs_release_data_page(struct page *page, gfp_t wait)
  643. {
  644. ClearPagePrivate(page);
  645. return 1;
  646. }
  647. static int f2fs_set_data_page_dirty(struct page *page)
  648. {
  649. struct address_space *mapping = page->mapping;
  650. struct inode *inode = mapping->host;
  651. SetPageUptodate(page);
  652. if (!PageDirty(page)) {
  653. __set_page_dirty_nobuffers(page);
  654. set_dirty_dir_page(inode, page);
  655. return 1;
  656. }
  657. return 0;
  658. }
  659. static sector_t f2fs_bmap(struct address_space *mapping, sector_t block)
  660. {
  661. return generic_block_bmap(mapping, block, get_data_block_ro);
  662. }
  663. const struct address_space_operations f2fs_dblock_aops = {
  664. .readpage = f2fs_read_data_page,
  665. .readpages = f2fs_read_data_pages,
  666. .writepage = f2fs_write_data_page,
  667. .writepages = f2fs_write_data_pages,
  668. .write_begin = f2fs_write_begin,
  669. .write_end = f2fs_write_end,
  670. .set_page_dirty = f2fs_set_data_page_dirty,
  671. .invalidatepage = f2fs_invalidate_data_page,
  672. .releasepage = f2fs_release_data_page,
  673. .direct_IO = f2fs_direct_IO,
  674. .bmap = f2fs_bmap,
  675. };