ops_address.c 19 KB

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  1. /*
  2. * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
  3. * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved.
  4. *
  5. * This copyrighted material is made available to anyone wishing to use,
  6. * modify, copy, or redistribute it subject to the terms and conditions
  7. * of the GNU General Public License v.2.
  8. */
  9. #include <linux/sched.h>
  10. #include <linux/slab.h>
  11. #include <linux/spinlock.h>
  12. #include <linux/completion.h>
  13. #include <linux/buffer_head.h>
  14. #include <linux/pagemap.h>
  15. #include <linux/pagevec.h>
  16. #include <linux/mpage.h>
  17. #include <linux/fs.h>
  18. #include <linux/gfs2_ondisk.h>
  19. #include "gfs2.h"
  20. #include "lm_interface.h"
  21. #include "incore.h"
  22. #include "bmap.h"
  23. #include "glock.h"
  24. #include "inode.h"
  25. #include "log.h"
  26. #include "meta_io.h"
  27. #include "ops_address.h"
  28. #include "quota.h"
  29. #include "trans.h"
  30. #include "rgrp.h"
  31. #include "ops_file.h"
  32. #include "util.h"
  33. #include "glops.h"
  34. static void gfs2_page_add_databufs(struct gfs2_inode *ip, struct page *page,
  35. unsigned int from, unsigned int to)
  36. {
  37. struct buffer_head *head = page_buffers(page);
  38. unsigned int bsize = head->b_size;
  39. struct buffer_head *bh;
  40. unsigned int start, end;
  41. for (bh = head, start = 0; bh != head || !start;
  42. bh = bh->b_this_page, start = end) {
  43. end = start + bsize;
  44. if (end <= from || start >= to)
  45. continue;
  46. gfs2_trans_add_bh(ip->i_gl, bh, 0);
  47. }
  48. }
  49. /**
  50. * gfs2_get_block - Fills in a buffer head with details about a block
  51. * @inode: The inode
  52. * @lblock: The block number to look up
  53. * @bh_result: The buffer head to return the result in
  54. * @create: Non-zero if we may add block to the file
  55. *
  56. * Returns: errno
  57. */
  58. int gfs2_get_block(struct inode *inode, sector_t lblock,
  59. struct buffer_head *bh_result, int create)
  60. {
  61. int new = create;
  62. uint64_t dblock;
  63. int error;
  64. int boundary;
  65. error = gfs2_block_map(inode, lblock, &new, &dblock, &boundary);
  66. if (error)
  67. return error;
  68. if (!dblock)
  69. return 0;
  70. map_bh(bh_result, inode->i_sb, dblock);
  71. if (new)
  72. set_buffer_new(bh_result);
  73. if (boundary)
  74. set_buffer_boundary(bh_result);
  75. return 0;
  76. }
  77. /**
  78. * get_block_noalloc - Fills in a buffer head with details about a block
  79. * @inode: The inode
  80. * @lblock: The block number to look up
  81. * @bh_result: The buffer head to return the result in
  82. * @create: Non-zero if we may add block to the file
  83. *
  84. * Returns: errno
  85. */
  86. static int get_block_noalloc(struct inode *inode, sector_t lblock,
  87. struct buffer_head *bh_result, int create)
  88. {
  89. int new = 0;
  90. uint64_t dblock;
  91. int error;
  92. int boundary;
  93. error = gfs2_block_map(inode, lblock, &new, &dblock, &boundary);
  94. if (error)
  95. return error;
  96. if (dblock)
  97. map_bh(bh_result, inode->i_sb, dblock);
  98. else if (gfs2_assert_withdraw(GFS2_SB(inode), !create))
  99. error = -EIO;
  100. if (boundary)
  101. set_buffer_boundary(bh_result);
  102. return error;
  103. }
  104. /**
  105. * gfs2_writepage - Write complete page
  106. * @page: Page to write
  107. *
  108. * Returns: errno
  109. *
  110. * Some of this is copied from block_write_full_page() although we still
  111. * call it to do most of the work.
  112. */
  113. static int gfs2_writepage(struct page *page, struct writeback_control *wbc)
  114. {
  115. struct inode *inode = page->mapping->host;
  116. struct gfs2_inode *ip = GFS2_I(inode);
  117. struct gfs2_sbd *sdp = GFS2_SB(inode);
  118. loff_t i_size = i_size_read(inode);
  119. pgoff_t end_index = i_size >> PAGE_CACHE_SHIFT;
  120. unsigned offset;
  121. int error;
  122. int done_trans = 0;
  123. if (gfs2_assert_withdraw(sdp, gfs2_glock_is_held_excl(ip->i_gl))) {
  124. unlock_page(page);
  125. return -EIO;
  126. }
  127. if (current->journal_info)
  128. goto out_ignore;
  129. /* Is the page fully outside i_size? (truncate in progress) */
  130. offset = i_size & (PAGE_CACHE_SIZE-1);
  131. if (page->index > end_index || (page->index == end_index && !offset)) {
  132. page->mapping->a_ops->invalidatepage(page, 0);
  133. unlock_page(page);
  134. return 0; /* don't care */
  135. }
  136. if (sdp->sd_args.ar_data == GFS2_DATA_ORDERED || gfs2_is_jdata(ip)) {
  137. error = gfs2_trans_begin(sdp, RES_DINODE + 1, 0);
  138. if (error)
  139. goto out_ignore;
  140. if (!page_has_buffers(page)) {
  141. create_empty_buffers(page, inode->i_sb->s_blocksize,
  142. (1 << BH_Dirty)|(1 << BH_Uptodate));
  143. }
  144. gfs2_page_add_databufs(ip, page, 0, sdp->sd_vfs->s_blocksize-1);
  145. done_trans = 1;
  146. }
  147. error = block_write_full_page(page, get_block_noalloc, wbc);
  148. if (done_trans)
  149. gfs2_trans_end(sdp);
  150. gfs2_meta_cache_flush(ip);
  151. return error;
  152. out_ignore:
  153. redirty_page_for_writepage(wbc, page);
  154. unlock_page(page);
  155. return 0;
  156. }
  157. static int zero_readpage(struct page *page)
  158. {
  159. void *kaddr;
  160. kaddr = kmap_atomic(page, KM_USER0);
  161. memset(kaddr, 0, PAGE_CACHE_SIZE);
  162. kunmap_atomic(page, KM_USER0);
  163. SetPageUptodate(page);
  164. return 0;
  165. }
  166. /**
  167. * stuffed_readpage - Fill in a Linux page with stuffed file data
  168. * @ip: the inode
  169. * @page: the page
  170. *
  171. * Returns: errno
  172. */
  173. static int stuffed_readpage(struct gfs2_inode *ip, struct page *page)
  174. {
  175. struct buffer_head *dibh;
  176. void *kaddr;
  177. int error;
  178. /* Only the first page of a stuffed file might contain data */
  179. if (unlikely(page->index))
  180. return zero_readpage(page);
  181. error = gfs2_meta_inode_buffer(ip, &dibh);
  182. if (error)
  183. return error;
  184. kaddr = kmap_atomic(page, KM_USER0);
  185. memcpy(kaddr, dibh->b_data + sizeof(struct gfs2_dinode),
  186. ip->i_di.di_size);
  187. memset(kaddr + ip->i_di.di_size, 0, PAGE_CACHE_SIZE - ip->i_di.di_size);
  188. kunmap_atomic(page, KM_USER0);
  189. brelse(dibh);
  190. SetPageUptodate(page);
  191. return 0;
  192. }
  193. /**
  194. * gfs2_readpage - readpage with locking
  195. * @file: The file to read a page for. N.B. This may be NULL if we are
  196. * reading an internal file.
  197. * @page: The page to read
  198. *
  199. * Returns: errno
  200. */
  201. static int gfs2_readpage(struct file *file, struct page *page)
  202. {
  203. struct gfs2_inode *ip = GFS2_I(page->mapping->host);
  204. struct gfs2_sbd *sdp = GFS2_SB(page->mapping->host);
  205. struct gfs2_holder gh;
  206. int error;
  207. int do_unlock = 0;
  208. if (likely(file != &gfs2_internal_file_sentinal)) {
  209. if (file) {
  210. struct gfs2_file *gf = file->private_data;
  211. if (test_bit(GFF_EXLOCK, &gf->f_flags))
  212. goto skip_lock;
  213. }
  214. gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME|GL_AOP, &gh);
  215. do_unlock = 1;
  216. error = gfs2_glock_nq_m_atime(1, &gh);
  217. if (unlikely(error))
  218. goto out_unlock;
  219. }
  220. skip_lock:
  221. if (gfs2_is_stuffed(ip)) {
  222. error = stuffed_readpage(ip, page);
  223. unlock_page(page);
  224. } else
  225. error = mpage_readpage(page, gfs2_get_block);
  226. if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
  227. error = -EIO;
  228. if (file != &gfs2_internal_file_sentinal) {
  229. gfs2_glock_dq_m(1, &gh);
  230. gfs2_holder_uninit(&gh);
  231. }
  232. out:
  233. return error;
  234. out_unlock:
  235. unlock_page(page);
  236. if (do_unlock)
  237. gfs2_holder_uninit(&gh);
  238. goto out;
  239. }
  240. /**
  241. * gfs2_readpages - Read a bunch of pages at once
  242. *
  243. * Some notes:
  244. * 1. This is only for readahead, so we can simply ignore any things
  245. * which are slightly inconvenient (such as locking conflicts between
  246. * the page lock and the glock) and return having done no I/O. Its
  247. * obviously not something we'd want to do on too regular a basis.
  248. * Any I/O we ignore at this time will be done via readpage later.
  249. * 2. We have to handle stuffed files here too.
  250. * 3. mpage_readpages() does most of the heavy lifting in the common case.
  251. * 4. gfs2_get_block() is relied upon to set BH_Boundary in the right places.
  252. * 5. We use LM_FLAG_TRY_1CB here, effectively we then have lock-ahead as
  253. * well as read-ahead.
  254. */
  255. static int gfs2_readpages(struct file *file, struct address_space *mapping,
  256. struct list_head *pages, unsigned nr_pages)
  257. {
  258. struct inode *inode = mapping->host;
  259. struct gfs2_inode *ip = GFS2_I(inode);
  260. struct gfs2_sbd *sdp = GFS2_SB(inode);
  261. struct gfs2_holder gh;
  262. unsigned page_idx;
  263. int ret;
  264. int do_unlock = 0;
  265. if (likely(file != &gfs2_internal_file_sentinal)) {
  266. if (file) {
  267. struct gfs2_file *gf = file->private_data;
  268. if (test_bit(GFF_EXLOCK, &gf->f_flags))
  269. goto skip_lock;
  270. }
  271. gfs2_holder_init(ip->i_gl, LM_ST_SHARED,
  272. LM_FLAG_TRY_1CB|GL_ATIME|GL_AOP, &gh);
  273. do_unlock = 1;
  274. ret = gfs2_glock_nq_m_atime(1, &gh);
  275. if (ret == GLR_TRYFAILED)
  276. goto out_noerror;
  277. if (unlikely(ret))
  278. goto out_unlock;
  279. }
  280. skip_lock:
  281. if (gfs2_is_stuffed(ip)) {
  282. struct pagevec lru_pvec;
  283. pagevec_init(&lru_pvec, 0);
  284. for (page_idx = 0; page_idx < nr_pages; page_idx++) {
  285. struct page *page = list_entry(pages->prev, struct page, lru);
  286. prefetchw(&page->flags);
  287. list_del(&page->lru);
  288. if (!add_to_page_cache(page, mapping,
  289. page->index, GFP_KERNEL)) {
  290. ret = stuffed_readpage(ip, page);
  291. unlock_page(page);
  292. if (!pagevec_add(&lru_pvec, page))
  293. __pagevec_lru_add(&lru_pvec);
  294. } else {
  295. page_cache_release(page);
  296. }
  297. }
  298. pagevec_lru_add(&lru_pvec);
  299. ret = 0;
  300. } else {
  301. /* What we really want to do .... */
  302. ret = mpage_readpages(mapping, pages, nr_pages, gfs2_get_block);
  303. }
  304. if (do_unlock) {
  305. gfs2_glock_dq_m(1, &gh);
  306. gfs2_holder_uninit(&gh);
  307. }
  308. out:
  309. if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags)))
  310. ret = -EIO;
  311. return ret;
  312. out_noerror:
  313. ret = 0;
  314. out_unlock:
  315. /* unlock all pages, we can't do any I/O right now */
  316. for (page_idx = 0; page_idx < nr_pages; page_idx++) {
  317. struct page *page = list_entry(pages->prev, struct page, lru);
  318. list_del(&page->lru);
  319. unlock_page(page);
  320. page_cache_release(page);
  321. }
  322. if (do_unlock)
  323. gfs2_holder_uninit(&gh);
  324. goto out;
  325. }
  326. /**
  327. * gfs2_prepare_write - Prepare to write a page to a file
  328. * @file: The file to write to
  329. * @page: The page which is to be prepared for writing
  330. * @from: From (byte range within page)
  331. * @to: To (byte range within page)
  332. *
  333. * Returns: errno
  334. */
  335. static int gfs2_prepare_write(struct file *file, struct page *page,
  336. unsigned from, unsigned to)
  337. {
  338. struct gfs2_inode *ip = GFS2_I(page->mapping->host);
  339. struct gfs2_sbd *sdp = GFS2_SB(page->mapping->host);
  340. unsigned int data_blocks, ind_blocks, rblocks;
  341. int alloc_required;
  342. int error = 0;
  343. loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + from;
  344. loff_t end = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
  345. struct gfs2_alloc *al;
  346. gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, GL_ATIME|GL_AOP, &ip->i_gh);
  347. error = gfs2_glock_nq_m_atime(1, &ip->i_gh);
  348. if (error)
  349. goto out_uninit;
  350. gfs2_write_calc_reserv(ip, to - from, &data_blocks, &ind_blocks);
  351. error = gfs2_write_alloc_required(ip, pos, from - to, &alloc_required);
  352. if (error)
  353. goto out_unlock;
  354. if (alloc_required) {
  355. al = gfs2_alloc_get(ip);
  356. error = gfs2_quota_lock(ip, NO_QUOTA_CHANGE, NO_QUOTA_CHANGE);
  357. if (error)
  358. goto out_alloc_put;
  359. error = gfs2_quota_check(ip, ip->i_di.di_uid, ip->i_di.di_gid);
  360. if (error)
  361. goto out_qunlock;
  362. al->al_requested = data_blocks + ind_blocks;
  363. error = gfs2_inplace_reserve(ip);
  364. if (error)
  365. goto out_qunlock;
  366. }
  367. rblocks = RES_DINODE + ind_blocks;
  368. if (gfs2_is_jdata(ip))
  369. rblocks += data_blocks ? data_blocks : 1;
  370. if (ind_blocks || data_blocks)
  371. rblocks += RES_STATFS + RES_QUOTA;
  372. error = gfs2_trans_begin(sdp, rblocks, 0);
  373. if (error)
  374. goto out;
  375. if (gfs2_is_stuffed(ip)) {
  376. if (end > sdp->sd_sb.sb_bsize - sizeof(struct gfs2_dinode)) {
  377. error = gfs2_unstuff_dinode(ip, page);
  378. if (error == 0)
  379. goto prepare_write;
  380. } else if (!PageUptodate(page))
  381. error = stuffed_readpage(ip, page);
  382. goto out;
  383. }
  384. prepare_write:
  385. error = block_prepare_write(page, from, to, gfs2_get_block);
  386. out:
  387. if (error) {
  388. gfs2_trans_end(sdp);
  389. if (alloc_required) {
  390. gfs2_inplace_release(ip);
  391. out_qunlock:
  392. gfs2_quota_unlock(ip);
  393. out_alloc_put:
  394. gfs2_alloc_put(ip);
  395. }
  396. out_unlock:
  397. gfs2_glock_dq_m(1, &ip->i_gh);
  398. out_uninit:
  399. gfs2_holder_uninit(&ip->i_gh);
  400. }
  401. return error;
  402. }
  403. /**
  404. * gfs2_commit_write - Commit write to a file
  405. * @file: The file to write to
  406. * @page: The page containing the data
  407. * @from: From (byte range within page)
  408. * @to: To (byte range within page)
  409. *
  410. * Returns: errno
  411. */
  412. static int gfs2_commit_write(struct file *file, struct page *page,
  413. unsigned from, unsigned to)
  414. {
  415. struct inode *inode = page->mapping->host;
  416. struct gfs2_inode *ip = GFS2_I(inode);
  417. struct gfs2_sbd *sdp = GFS2_SB(inode);
  418. int error = -EOPNOTSUPP;
  419. struct buffer_head *dibh;
  420. struct gfs2_alloc *al = &ip->i_alloc;;
  421. if (gfs2_assert_withdraw(sdp, gfs2_glock_is_locked_by_me(ip->i_gl)))
  422. goto fail_nounlock;
  423. error = gfs2_meta_inode_buffer(ip, &dibh);
  424. if (error)
  425. goto fail_endtrans;
  426. gfs2_trans_add_bh(ip->i_gl, dibh, 1);
  427. if (gfs2_is_stuffed(ip)) {
  428. uint64_t file_size;
  429. void *kaddr;
  430. file_size = ((uint64_t)page->index << PAGE_CACHE_SHIFT) + to;
  431. kaddr = kmap_atomic(page, KM_USER0);
  432. memcpy(dibh->b_data + sizeof(struct gfs2_dinode) + from,
  433. (char *)kaddr + from, to - from);
  434. kunmap_atomic(page, KM_USER0);
  435. SetPageUptodate(page);
  436. if (inode->i_size < file_size)
  437. i_size_write(inode, file_size);
  438. } else {
  439. if (sdp->sd_args.ar_data == GFS2_DATA_ORDERED ||
  440. gfs2_is_jdata(ip))
  441. gfs2_page_add_databufs(ip, page, from, to);
  442. error = generic_commit_write(file, page, from, to);
  443. if (error)
  444. goto fail;
  445. }
  446. if (ip->i_di.di_size < inode->i_size)
  447. ip->i_di.di_size = inode->i_size;
  448. gfs2_dinode_out(&ip->i_di, dibh->b_data);
  449. brelse(dibh);
  450. gfs2_trans_end(sdp);
  451. if (al->al_requested) {
  452. gfs2_inplace_release(ip);
  453. gfs2_quota_unlock(ip);
  454. gfs2_alloc_put(ip);
  455. }
  456. gfs2_glock_dq_m(1, &ip->i_gh);
  457. gfs2_holder_uninit(&ip->i_gh);
  458. return 0;
  459. fail:
  460. brelse(dibh);
  461. fail_endtrans:
  462. gfs2_trans_end(sdp);
  463. if (al->al_requested) {
  464. gfs2_inplace_release(ip);
  465. gfs2_quota_unlock(ip);
  466. gfs2_alloc_put(ip);
  467. }
  468. gfs2_glock_dq_m(1, &ip->i_gh);
  469. gfs2_holder_uninit(&ip->i_gh);
  470. fail_nounlock:
  471. ClearPageUptodate(page);
  472. return error;
  473. }
  474. /**
  475. * gfs2_bmap - Block map function
  476. * @mapping: Address space info
  477. * @lblock: The block to map
  478. *
  479. * Returns: The disk address for the block or 0 on hole or error
  480. */
  481. static sector_t gfs2_bmap(struct address_space *mapping, sector_t lblock)
  482. {
  483. struct gfs2_inode *ip = GFS2_I(mapping->host);
  484. struct gfs2_holder i_gh;
  485. sector_t dblock = 0;
  486. int error;
  487. error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh);
  488. if (error)
  489. return 0;
  490. if (!gfs2_is_stuffed(ip))
  491. dblock = generic_block_bmap(mapping, lblock, gfs2_get_block);
  492. gfs2_glock_dq_uninit(&i_gh);
  493. return dblock;
  494. }
  495. static void discard_buffer(struct gfs2_sbd *sdp, struct buffer_head *bh)
  496. {
  497. struct gfs2_bufdata *bd;
  498. gfs2_log_lock(sdp);
  499. bd = bh->b_private;
  500. if (bd) {
  501. bd->bd_bh = NULL;
  502. bh->b_private = NULL;
  503. }
  504. gfs2_log_unlock(sdp);
  505. lock_buffer(bh);
  506. clear_buffer_dirty(bh);
  507. bh->b_bdev = NULL;
  508. clear_buffer_mapped(bh);
  509. clear_buffer_req(bh);
  510. clear_buffer_new(bh);
  511. clear_buffer_delay(bh);
  512. unlock_buffer(bh);
  513. }
  514. static void gfs2_invalidatepage(struct page *page, unsigned long offset)
  515. {
  516. struct gfs2_sbd *sdp = GFS2_SB(page->mapping->host);
  517. struct buffer_head *head, *bh, *next;
  518. unsigned int curr_off = 0;
  519. BUG_ON(!PageLocked(page));
  520. if (!page_has_buffers(page))
  521. return;
  522. bh = head = page_buffers(page);
  523. do {
  524. unsigned int next_off = curr_off + bh->b_size;
  525. next = bh->b_this_page;
  526. if (offset <= curr_off)
  527. discard_buffer(sdp, bh);
  528. curr_off = next_off;
  529. bh = next;
  530. } while (bh != head);
  531. if (!offset)
  532. try_to_release_page(page, 0);
  533. return;
  534. }
  535. static ssize_t gfs2_direct_IO(int rw, struct kiocb *iocb,
  536. const struct iovec *iov, loff_t offset,
  537. unsigned long nr_segs)
  538. {
  539. struct file *file = iocb->ki_filp;
  540. struct inode *inode = file->f_mapping->host;
  541. struct gfs2_inode *ip = GFS2_I(inode);
  542. struct gfs2_holder gh;
  543. int rv;
  544. if (rw == READ)
  545. mutex_lock(&inode->i_mutex);
  546. /*
  547. * Shared lock, even if its a write, since we do no allocation
  548. * on this path. All we need change is atime.
  549. */
  550. gfs2_holder_init(ip->i_gl, LM_ST_SHARED, GL_ATIME, &gh);
  551. rv = gfs2_glock_nq_m_atime(1, &gh);
  552. if (rv)
  553. goto out;
  554. if (offset > i_size_read(inode))
  555. goto out;
  556. /*
  557. * Should we return an error here? I can't see that O_DIRECT for
  558. * a journaled file makes any sense. For now we'll silently fall
  559. * back to buffered I/O, likewise we do the same for stuffed
  560. * files since they are (a) small and (b) unaligned.
  561. */
  562. if (gfs2_is_jdata(ip))
  563. goto out;
  564. if (gfs2_is_stuffed(ip))
  565. goto out;
  566. rv = blockdev_direct_IO_own_locking(rw, iocb, inode,
  567. inode->i_sb->s_bdev,
  568. iov, offset, nr_segs,
  569. gfs2_get_block, NULL);
  570. out:
  571. gfs2_glock_dq_m(1, &gh);
  572. gfs2_holder_uninit(&gh);
  573. if (rw == READ)
  574. mutex_unlock(&inode->i_mutex);
  575. return rv;
  576. }
  577. /**
  578. * stuck_releasepage - We're stuck in gfs2_releasepage(). Print stuff out.
  579. * @bh: the buffer we're stuck on
  580. *
  581. */
  582. static void stuck_releasepage(struct buffer_head *bh)
  583. {
  584. struct inode *inode = bh->b_page->mapping->host;
  585. struct gfs2_sbd *sdp = inode->i_sb->s_fs_info;
  586. struct gfs2_bufdata *bd = bh->b_private;
  587. struct gfs2_glock *gl;
  588. fs_warn(sdp, "stuck in gfs2_releasepage() %p\n", inode);
  589. fs_warn(sdp, "blkno = %llu, bh->b_count = %d\n",
  590. (unsigned long long)bh->b_blocknr, atomic_read(&bh->b_count));
  591. fs_warn(sdp, "pinned = %u\n", buffer_pinned(bh));
  592. fs_warn(sdp, "bh->b_private = %s\n", (bd) ? "!NULL" : "NULL");
  593. if (!bd)
  594. return;
  595. gl = bd->bd_gl;
  596. fs_warn(sdp, "gl = (%u, %llu)\n",
  597. gl->gl_name.ln_type, (unsigned long long)gl->gl_name.ln_number);
  598. fs_warn(sdp, "bd_list_tr = %s, bd_le.le_list = %s\n",
  599. (list_empty(&bd->bd_list_tr)) ? "no" : "yes",
  600. (list_empty(&bd->bd_le.le_list)) ? "no" : "yes");
  601. if (gl->gl_ops == &gfs2_inode_glops) {
  602. struct gfs2_inode *ip = gl->gl_object;
  603. unsigned int x;
  604. if (!ip)
  605. return;
  606. fs_warn(sdp, "ip = %llu %llu\n",
  607. (unsigned long long)ip->i_num.no_formal_ino,
  608. (unsigned long long)ip->i_num.no_addr);
  609. for (x = 0; x < GFS2_MAX_META_HEIGHT; x++)
  610. fs_warn(sdp, "ip->i_cache[%u] = %s\n",
  611. x, (ip->i_cache[x]) ? "!NULL" : "NULL");
  612. }
  613. }
  614. /**
  615. * gfs2_aspace_releasepage - free the metadata associated with a page
  616. * @page: the page that's being released
  617. * @gfp_mask: passed from Linux VFS, ignored by us
  618. *
  619. * Call try_to_free_buffers() if the buffers in this page can be
  620. * released.
  621. *
  622. * Returns: 0
  623. */
  624. int gfs2_releasepage(struct page *page, gfp_t gfp_mask)
  625. {
  626. struct inode *aspace = page->mapping->host;
  627. struct gfs2_sbd *sdp = aspace->i_sb->s_fs_info;
  628. struct buffer_head *bh, *head;
  629. struct gfs2_bufdata *bd;
  630. unsigned long t;
  631. if (!page_has_buffers(page))
  632. goto out;
  633. head = bh = page_buffers(page);
  634. do {
  635. t = jiffies;
  636. while (atomic_read(&bh->b_count)) {
  637. if (atomic_read(&aspace->i_writecount)) {
  638. if (time_after_eq(jiffies, t +
  639. gfs2_tune_get(sdp, gt_stall_secs) * HZ)) {
  640. stuck_releasepage(bh);
  641. t = jiffies;
  642. }
  643. yield();
  644. continue;
  645. }
  646. return 0;
  647. }
  648. gfs2_assert_warn(sdp, !buffer_pinned(bh));
  649. bd = bh->b_private;
  650. if (bd) {
  651. gfs2_assert_warn(sdp, bd->bd_bh == bh);
  652. gfs2_assert_warn(sdp, list_empty(&bd->bd_list_tr));
  653. gfs2_assert_warn(sdp, list_empty(&bd->bd_le.le_list));
  654. gfs2_assert_warn(sdp, !bd->bd_ail);
  655. kmem_cache_free(gfs2_bufdata_cachep, bd);
  656. bh->b_private = NULL;
  657. }
  658. bh = bh->b_this_page;
  659. }
  660. while (bh != head);
  661. out:
  662. return try_to_free_buffers(page);
  663. }
  664. const struct address_space_operations gfs2_file_aops = {
  665. .writepage = gfs2_writepage,
  666. .readpage = gfs2_readpage,
  667. .readpages = gfs2_readpages,
  668. .sync_page = block_sync_page,
  669. .prepare_write = gfs2_prepare_write,
  670. .commit_write = gfs2_commit_write,
  671. .bmap = gfs2_bmap,
  672. .invalidatepage = gfs2_invalidatepage,
  673. .releasepage = gfs2_releasepage,
  674. .direct_IO = gfs2_direct_IO,
  675. };