xref: /openbmc/linux/fs/ocfs2/aops.c (revision 9d56dd3b083a3bec56e9da35ce07baca81030b03)
1 /* -*- mode: c; c-basic-offset: 8; -*-
2  * vim: noexpandtab sw=8 ts=8 sts=0:
3  *
4  * Copyright (C) 2002, 2004 Oracle.  All rights reserved.
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public
8  * License as published by the Free Software Foundation; either
9  * version 2 of the License, or (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public
17  * License along with this program; if not, write to the
18  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19  * Boston, MA 021110-1307, USA.
20  */
21 
22 #include <linux/fs.h>
23 #include <linux/slab.h>
24 #include <linux/highmem.h>
25 #include <linux/pagemap.h>
26 #include <asm/byteorder.h>
27 #include <linux/swap.h>
28 #include <linux/pipe_fs_i.h>
29 #include <linux/mpage.h>
30 #include <linux/quotaops.h>
31 
32 #define MLOG_MASK_PREFIX ML_FILE_IO
33 #include <cluster/masklog.h>
34 
35 #include "ocfs2.h"
36 
37 #include "alloc.h"
38 #include "aops.h"
39 #include "dlmglue.h"
40 #include "extent_map.h"
41 #include "file.h"
42 #include "inode.h"
43 #include "journal.h"
44 #include "suballoc.h"
45 #include "super.h"
46 #include "symlink.h"
47 #include "refcounttree.h"
48 
49 #include "buffer_head_io.h"
50 
51 static int ocfs2_symlink_get_block(struct inode *inode, sector_t iblock,
52 				   struct buffer_head *bh_result, int create)
53 {
54 	int err = -EIO;
55 	int status;
56 	struct ocfs2_dinode *fe = NULL;
57 	struct buffer_head *bh = NULL;
58 	struct buffer_head *buffer_cache_bh = NULL;
59 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
60 	void *kaddr;
61 
62 	mlog_entry("(0x%p, %llu, 0x%p, %d)\n", inode,
63 		   (unsigned long long)iblock, bh_result, create);
64 
65 	BUG_ON(ocfs2_inode_is_fast_symlink(inode));
66 
67 	if ((iblock << inode->i_sb->s_blocksize_bits) > PATH_MAX + 1) {
68 		mlog(ML_ERROR, "block offset > PATH_MAX: %llu",
69 		     (unsigned long long)iblock);
70 		goto bail;
71 	}
72 
73 	status = ocfs2_read_inode_block(inode, &bh);
74 	if (status < 0) {
75 		mlog_errno(status);
76 		goto bail;
77 	}
78 	fe = (struct ocfs2_dinode *) bh->b_data;
79 
80 	if ((u64)iblock >= ocfs2_clusters_to_blocks(inode->i_sb,
81 						    le32_to_cpu(fe->i_clusters))) {
82 		mlog(ML_ERROR, "block offset is outside the allocated size: "
83 		     "%llu\n", (unsigned long long)iblock);
84 		goto bail;
85 	}
86 
87 	/* We don't use the page cache to create symlink data, so if
88 	 * need be, copy it over from the buffer cache. */
89 	if (!buffer_uptodate(bh_result) && ocfs2_inode_is_new(inode)) {
90 		u64 blkno = le64_to_cpu(fe->id2.i_list.l_recs[0].e_blkno) +
91 			    iblock;
92 		buffer_cache_bh = sb_getblk(osb->sb, blkno);
93 		if (!buffer_cache_bh) {
94 			mlog(ML_ERROR, "couldn't getblock for symlink!\n");
95 			goto bail;
96 		}
97 
98 		/* we haven't locked out transactions, so a commit
99 		 * could've happened. Since we've got a reference on
100 		 * the bh, even if it commits while we're doing the
101 		 * copy, the data is still good. */
102 		if (buffer_jbd(buffer_cache_bh)
103 		    && ocfs2_inode_is_new(inode)) {
104 			kaddr = kmap_atomic(bh_result->b_page, KM_USER0);
105 			if (!kaddr) {
106 				mlog(ML_ERROR, "couldn't kmap!\n");
107 				goto bail;
108 			}
109 			memcpy(kaddr + (bh_result->b_size * iblock),
110 			       buffer_cache_bh->b_data,
111 			       bh_result->b_size);
112 			kunmap_atomic(kaddr, KM_USER0);
113 			set_buffer_uptodate(bh_result);
114 		}
115 		brelse(buffer_cache_bh);
116 	}
117 
118 	map_bh(bh_result, inode->i_sb,
119 	       le64_to_cpu(fe->id2.i_list.l_recs[0].e_blkno) + iblock);
120 
121 	err = 0;
122 
123 bail:
124 	brelse(bh);
125 
126 	mlog_exit(err);
127 	return err;
128 }
129 
130 int ocfs2_get_block(struct inode *inode, sector_t iblock,
131 		    struct buffer_head *bh_result, int create)
132 {
133 	int err = 0;
134 	unsigned int ext_flags;
135 	u64 max_blocks = bh_result->b_size >> inode->i_blkbits;
136 	u64 p_blkno, count, past_eof;
137 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
138 
139 	mlog_entry("(0x%p, %llu, 0x%p, %d)\n", inode,
140 		   (unsigned long long)iblock, bh_result, create);
141 
142 	if (OCFS2_I(inode)->ip_flags & OCFS2_INODE_SYSTEM_FILE)
143 		mlog(ML_NOTICE, "get_block on system inode 0x%p (%lu)\n",
144 		     inode, inode->i_ino);
145 
146 	if (S_ISLNK(inode->i_mode)) {
147 		/* this always does I/O for some reason. */
148 		err = ocfs2_symlink_get_block(inode, iblock, bh_result, create);
149 		goto bail;
150 	}
151 
152 	err = ocfs2_extent_map_get_blocks(inode, iblock, &p_blkno, &count,
153 					  &ext_flags);
154 	if (err) {
155 		mlog(ML_ERROR, "Error %d from get_blocks(0x%p, %llu, 1, "
156 		     "%llu, NULL)\n", err, inode, (unsigned long long)iblock,
157 		     (unsigned long long)p_blkno);
158 		goto bail;
159 	}
160 
161 	if (max_blocks < count)
162 		count = max_blocks;
163 
164 	/*
165 	 * ocfs2 never allocates in this function - the only time we
166 	 * need to use BH_New is when we're extending i_size on a file
167 	 * system which doesn't support holes, in which case BH_New
168 	 * allows block_prepare_write() to zero.
169 	 *
170 	 * If we see this on a sparse file system, then a truncate has
171 	 * raced us and removed the cluster. In this case, we clear
172 	 * the buffers dirty and uptodate bits and let the buffer code
173 	 * ignore it as a hole.
174 	 */
175 	if (create && p_blkno == 0 && ocfs2_sparse_alloc(osb)) {
176 		clear_buffer_dirty(bh_result);
177 		clear_buffer_uptodate(bh_result);
178 		goto bail;
179 	}
180 
181 	/* Treat the unwritten extent as a hole for zeroing purposes. */
182 	if (p_blkno && !(ext_flags & OCFS2_EXT_UNWRITTEN))
183 		map_bh(bh_result, inode->i_sb, p_blkno);
184 
185 	bh_result->b_size = count << inode->i_blkbits;
186 
187 	if (!ocfs2_sparse_alloc(osb)) {
188 		if (p_blkno == 0) {
189 			err = -EIO;
190 			mlog(ML_ERROR,
191 			     "iblock = %llu p_blkno = %llu blkno=(%llu)\n",
192 			     (unsigned long long)iblock,
193 			     (unsigned long long)p_blkno,
194 			     (unsigned long long)OCFS2_I(inode)->ip_blkno);
195 			mlog(ML_ERROR, "Size %llu, clusters %u\n", (unsigned long long)i_size_read(inode), OCFS2_I(inode)->ip_clusters);
196 			dump_stack();
197 			goto bail;
198 		}
199 
200 		past_eof = ocfs2_blocks_for_bytes(inode->i_sb, i_size_read(inode));
201 		mlog(0, "Inode %lu, past_eof = %llu\n", inode->i_ino,
202 		     (unsigned long long)past_eof);
203 
204 		if (create && (iblock >= past_eof))
205 			set_buffer_new(bh_result);
206 	}
207 
208 bail:
209 	if (err < 0)
210 		err = -EIO;
211 
212 	mlog_exit(err);
213 	return err;
214 }
215 
216 int ocfs2_read_inline_data(struct inode *inode, struct page *page,
217 			   struct buffer_head *di_bh)
218 {
219 	void *kaddr;
220 	loff_t size;
221 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
222 
223 	if (!(le16_to_cpu(di->i_dyn_features) & OCFS2_INLINE_DATA_FL)) {
224 		ocfs2_error(inode->i_sb, "Inode %llu lost inline data flag",
225 			    (unsigned long long)OCFS2_I(inode)->ip_blkno);
226 		return -EROFS;
227 	}
228 
229 	size = i_size_read(inode);
230 
231 	if (size > PAGE_CACHE_SIZE ||
232 	    size > ocfs2_max_inline_data_with_xattr(inode->i_sb, di)) {
233 		ocfs2_error(inode->i_sb,
234 			    "Inode %llu has with inline data has bad size: %Lu",
235 			    (unsigned long long)OCFS2_I(inode)->ip_blkno,
236 			    (unsigned long long)size);
237 		return -EROFS;
238 	}
239 
240 	kaddr = kmap_atomic(page, KM_USER0);
241 	if (size)
242 		memcpy(kaddr, di->id2.i_data.id_data, size);
243 	/* Clear the remaining part of the page */
244 	memset(kaddr + size, 0, PAGE_CACHE_SIZE - size);
245 	flush_dcache_page(page);
246 	kunmap_atomic(kaddr, KM_USER0);
247 
248 	SetPageUptodate(page);
249 
250 	return 0;
251 }
252 
253 static int ocfs2_readpage_inline(struct inode *inode, struct page *page)
254 {
255 	int ret;
256 	struct buffer_head *di_bh = NULL;
257 
258 	BUG_ON(!PageLocked(page));
259 	BUG_ON(!(OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL));
260 
261 	ret = ocfs2_read_inode_block(inode, &di_bh);
262 	if (ret) {
263 		mlog_errno(ret);
264 		goto out;
265 	}
266 
267 	ret = ocfs2_read_inline_data(inode, page, di_bh);
268 out:
269 	unlock_page(page);
270 
271 	brelse(di_bh);
272 	return ret;
273 }
274 
275 static int ocfs2_readpage(struct file *file, struct page *page)
276 {
277 	struct inode *inode = page->mapping->host;
278 	struct ocfs2_inode_info *oi = OCFS2_I(inode);
279 	loff_t start = (loff_t)page->index << PAGE_CACHE_SHIFT;
280 	int ret, unlock = 1;
281 
282 	mlog_entry("(0x%p, %lu)\n", file, (page ? page->index : 0));
283 
284 	ret = ocfs2_inode_lock_with_page(inode, NULL, 0, page);
285 	if (ret != 0) {
286 		if (ret == AOP_TRUNCATED_PAGE)
287 			unlock = 0;
288 		mlog_errno(ret);
289 		goto out;
290 	}
291 
292 	if (down_read_trylock(&oi->ip_alloc_sem) == 0) {
293 		ret = AOP_TRUNCATED_PAGE;
294 		goto out_inode_unlock;
295 	}
296 
297 	/*
298 	 * i_size might have just been updated as we grabed the meta lock.  We
299 	 * might now be discovering a truncate that hit on another node.
300 	 * block_read_full_page->get_block freaks out if it is asked to read
301 	 * beyond the end of a file, so we check here.  Callers
302 	 * (generic_file_read, vm_ops->fault) are clever enough to check i_size
303 	 * and notice that the page they just read isn't needed.
304 	 *
305 	 * XXX sys_readahead() seems to get that wrong?
306 	 */
307 	if (start >= i_size_read(inode)) {
308 		zero_user(page, 0, PAGE_SIZE);
309 		SetPageUptodate(page);
310 		ret = 0;
311 		goto out_alloc;
312 	}
313 
314 	if (oi->ip_dyn_features & OCFS2_INLINE_DATA_FL)
315 		ret = ocfs2_readpage_inline(inode, page);
316 	else
317 		ret = block_read_full_page(page, ocfs2_get_block);
318 	unlock = 0;
319 
320 out_alloc:
321 	up_read(&OCFS2_I(inode)->ip_alloc_sem);
322 out_inode_unlock:
323 	ocfs2_inode_unlock(inode, 0);
324 out:
325 	if (unlock)
326 		unlock_page(page);
327 	mlog_exit(ret);
328 	return ret;
329 }
330 
331 /*
332  * This is used only for read-ahead. Failures or difficult to handle
333  * situations are safe to ignore.
334  *
335  * Right now, we don't bother with BH_Boundary - in-inode extent lists
336  * are quite large (243 extents on 4k blocks), so most inodes don't
337  * grow out to a tree. If need be, detecting boundary extents could
338  * trivially be added in a future version of ocfs2_get_block().
339  */
340 static int ocfs2_readpages(struct file *filp, struct address_space *mapping,
341 			   struct list_head *pages, unsigned nr_pages)
342 {
343 	int ret, err = -EIO;
344 	struct inode *inode = mapping->host;
345 	struct ocfs2_inode_info *oi = OCFS2_I(inode);
346 	loff_t start;
347 	struct page *last;
348 
349 	/*
350 	 * Use the nonblocking flag for the dlm code to avoid page
351 	 * lock inversion, but don't bother with retrying.
352 	 */
353 	ret = ocfs2_inode_lock_full(inode, NULL, 0, OCFS2_LOCK_NONBLOCK);
354 	if (ret)
355 		return err;
356 
357 	if (down_read_trylock(&oi->ip_alloc_sem) == 0) {
358 		ocfs2_inode_unlock(inode, 0);
359 		return err;
360 	}
361 
362 	/*
363 	 * Don't bother with inline-data. There isn't anything
364 	 * to read-ahead in that case anyway...
365 	 */
366 	if (oi->ip_dyn_features & OCFS2_INLINE_DATA_FL)
367 		goto out_unlock;
368 
369 	/*
370 	 * Check whether a remote node truncated this file - we just
371 	 * drop out in that case as it's not worth handling here.
372 	 */
373 	last = list_entry(pages->prev, struct page, lru);
374 	start = (loff_t)last->index << PAGE_CACHE_SHIFT;
375 	if (start >= i_size_read(inode))
376 		goto out_unlock;
377 
378 	err = mpage_readpages(mapping, pages, nr_pages, ocfs2_get_block);
379 
380 out_unlock:
381 	up_read(&oi->ip_alloc_sem);
382 	ocfs2_inode_unlock(inode, 0);
383 
384 	return err;
385 }
386 
387 /* Note: Because we don't support holes, our allocation has
388  * already happened (allocation writes zeros to the file data)
389  * so we don't have to worry about ordered writes in
390  * ocfs2_writepage.
391  *
392  * ->writepage is called during the process of invalidating the page cache
393  * during blocked lock processing.  It can't block on any cluster locks
394  * to during block mapping.  It's relying on the fact that the block
395  * mapping can't have disappeared under the dirty pages that it is
396  * being asked to write back.
397  */
398 static int ocfs2_writepage(struct page *page, struct writeback_control *wbc)
399 {
400 	int ret;
401 
402 	mlog_entry("(0x%p)\n", page);
403 
404 	ret = block_write_full_page(page, ocfs2_get_block, wbc);
405 
406 	mlog_exit(ret);
407 
408 	return ret;
409 }
410 
411 /*
412  * This is called from ocfs2_write_zero_page() which has handled it's
413  * own cluster locking and has ensured allocation exists for those
414  * blocks to be written.
415  */
416 int ocfs2_prepare_write_nolock(struct inode *inode, struct page *page,
417 			       unsigned from, unsigned to)
418 {
419 	int ret;
420 
421 	ret = block_prepare_write(page, from, to, ocfs2_get_block);
422 
423 	return ret;
424 }
425 
426 /* Taken from ext3. We don't necessarily need the full blown
427  * functionality yet, but IMHO it's better to cut and paste the whole
428  * thing so we can avoid introducing our own bugs (and easily pick up
429  * their fixes when they happen) --Mark */
430 int walk_page_buffers(	handle_t *handle,
431 			struct buffer_head *head,
432 			unsigned from,
433 			unsigned to,
434 			int *partial,
435 			int (*fn)(	handle_t *handle,
436 					struct buffer_head *bh))
437 {
438 	struct buffer_head *bh;
439 	unsigned block_start, block_end;
440 	unsigned blocksize = head->b_size;
441 	int err, ret = 0;
442 	struct buffer_head *next;
443 
444 	for (	bh = head, block_start = 0;
445 		ret == 0 && (bh != head || !block_start);
446 	    	block_start = block_end, bh = next)
447 	{
448 		next = bh->b_this_page;
449 		block_end = block_start + blocksize;
450 		if (block_end <= from || block_start >= to) {
451 			if (partial && !buffer_uptodate(bh))
452 				*partial = 1;
453 			continue;
454 		}
455 		err = (*fn)(handle, bh);
456 		if (!ret)
457 			ret = err;
458 	}
459 	return ret;
460 }
461 
462 handle_t *ocfs2_start_walk_page_trans(struct inode *inode,
463 							 struct page *page,
464 							 unsigned from,
465 							 unsigned to)
466 {
467 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
468 	handle_t *handle;
469 	int ret = 0;
470 
471 	handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
472 	if (IS_ERR(handle)) {
473 		ret = -ENOMEM;
474 		mlog_errno(ret);
475 		goto out;
476 	}
477 
478 	if (ocfs2_should_order_data(inode)) {
479 		ret = ocfs2_jbd2_file_inode(handle, inode);
480 		if (ret < 0)
481 			mlog_errno(ret);
482 	}
483 out:
484 	if (ret) {
485 		if (!IS_ERR(handle))
486 			ocfs2_commit_trans(osb, handle);
487 		handle = ERR_PTR(ret);
488 	}
489 	return handle;
490 }
491 
492 static sector_t ocfs2_bmap(struct address_space *mapping, sector_t block)
493 {
494 	sector_t status;
495 	u64 p_blkno = 0;
496 	int err = 0;
497 	struct inode *inode = mapping->host;
498 
499 	mlog_entry("(block = %llu)\n", (unsigned long long)block);
500 
501 	/* We don't need to lock journal system files, since they aren't
502 	 * accessed concurrently from multiple nodes.
503 	 */
504 	if (!INODE_JOURNAL(inode)) {
505 		err = ocfs2_inode_lock(inode, NULL, 0);
506 		if (err) {
507 			if (err != -ENOENT)
508 				mlog_errno(err);
509 			goto bail;
510 		}
511 		down_read(&OCFS2_I(inode)->ip_alloc_sem);
512 	}
513 
514 	if (!(OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL))
515 		err = ocfs2_extent_map_get_blocks(inode, block, &p_blkno, NULL,
516 						  NULL);
517 
518 	if (!INODE_JOURNAL(inode)) {
519 		up_read(&OCFS2_I(inode)->ip_alloc_sem);
520 		ocfs2_inode_unlock(inode, 0);
521 	}
522 
523 	if (err) {
524 		mlog(ML_ERROR, "get_blocks() failed, block = %llu\n",
525 		     (unsigned long long)block);
526 		mlog_errno(err);
527 		goto bail;
528 	}
529 
530 bail:
531 	status = err ? 0 : p_blkno;
532 
533 	mlog_exit((int)status);
534 
535 	return status;
536 }
537 
538 /*
539  * TODO: Make this into a generic get_blocks function.
540  *
541  * From do_direct_io in direct-io.c:
542  *  "So what we do is to permit the ->get_blocks function to populate
543  *   bh.b_size with the size of IO which is permitted at this offset and
544  *   this i_blkbits."
545  *
546  * This function is called directly from get_more_blocks in direct-io.c.
547  *
548  * called like this: dio->get_blocks(dio->inode, fs_startblk,
549  * 					fs_count, map_bh, dio->rw == WRITE);
550  *
551  * Note that we never bother to allocate blocks here, and thus ignore the
552  * create argument.
553  */
554 static int ocfs2_direct_IO_get_blocks(struct inode *inode, sector_t iblock,
555 				     struct buffer_head *bh_result, int create)
556 {
557 	int ret;
558 	u64 p_blkno, inode_blocks, contig_blocks;
559 	unsigned int ext_flags;
560 	unsigned char blocksize_bits = inode->i_sb->s_blocksize_bits;
561 	unsigned long max_blocks = bh_result->b_size >> inode->i_blkbits;
562 
563 	/* This function won't even be called if the request isn't all
564 	 * nicely aligned and of the right size, so there's no need
565 	 * for us to check any of that. */
566 
567 	inode_blocks = ocfs2_blocks_for_bytes(inode->i_sb, i_size_read(inode));
568 
569 	/* This figures out the size of the next contiguous block, and
570 	 * our logical offset */
571 	ret = ocfs2_extent_map_get_blocks(inode, iblock, &p_blkno,
572 					  &contig_blocks, &ext_flags);
573 	if (ret) {
574 		mlog(ML_ERROR, "get_blocks() failed iblock=%llu\n",
575 		     (unsigned long long)iblock);
576 		ret = -EIO;
577 		goto bail;
578 	}
579 
580 	/* We should already CoW the refcounted extent. */
581 	BUG_ON(ext_flags & OCFS2_EXT_REFCOUNTED);
582 	/*
583 	 * get_more_blocks() expects us to describe a hole by clearing
584 	 * the mapped bit on bh_result().
585 	 *
586 	 * Consider an unwritten extent as a hole.
587 	 */
588 	if (p_blkno && !(ext_flags & OCFS2_EXT_UNWRITTEN))
589 		map_bh(bh_result, inode->i_sb, p_blkno);
590 	else
591 		clear_buffer_mapped(bh_result);
592 
593 	/* make sure we don't map more than max_blocks blocks here as
594 	   that's all the kernel will handle at this point. */
595 	if (max_blocks < contig_blocks)
596 		contig_blocks = max_blocks;
597 	bh_result->b_size = contig_blocks << blocksize_bits;
598 bail:
599 	return ret;
600 }
601 
602 /*
603  * ocfs2_dio_end_io is called by the dio core when a dio is finished.  We're
604  * particularly interested in the aio/dio case.  Like the core uses
605  * i_alloc_sem, we use the rw_lock DLM lock to protect io on one node from
606  * truncation on another.
607  */
608 static void ocfs2_dio_end_io(struct kiocb *iocb,
609 			     loff_t offset,
610 			     ssize_t bytes,
611 			     void *private)
612 {
613 	struct inode *inode = iocb->ki_filp->f_path.dentry->d_inode;
614 	int level;
615 
616 	/* this io's submitter should not have unlocked this before we could */
617 	BUG_ON(!ocfs2_iocb_is_rw_locked(iocb));
618 
619 	ocfs2_iocb_clear_rw_locked(iocb);
620 
621 	level = ocfs2_iocb_rw_locked_level(iocb);
622 	if (!level)
623 		up_read(&inode->i_alloc_sem);
624 	ocfs2_rw_unlock(inode, level);
625 }
626 
627 /*
628  * ocfs2_invalidatepage() and ocfs2_releasepage() are shamelessly stolen
629  * from ext3.  PageChecked() bits have been removed as OCFS2 does not
630  * do journalled data.
631  */
632 static void ocfs2_invalidatepage(struct page *page, unsigned long offset)
633 {
634 	journal_t *journal = OCFS2_SB(page->mapping->host->i_sb)->journal->j_journal;
635 
636 	jbd2_journal_invalidatepage(journal, page, offset);
637 }
638 
639 static int ocfs2_releasepage(struct page *page, gfp_t wait)
640 {
641 	journal_t *journal = OCFS2_SB(page->mapping->host->i_sb)->journal->j_journal;
642 
643 	if (!page_has_buffers(page))
644 		return 0;
645 	return jbd2_journal_try_to_free_buffers(journal, page, wait);
646 }
647 
648 static ssize_t ocfs2_direct_IO(int rw,
649 			       struct kiocb *iocb,
650 			       const struct iovec *iov,
651 			       loff_t offset,
652 			       unsigned long nr_segs)
653 {
654 	struct file *file = iocb->ki_filp;
655 	struct inode *inode = file->f_path.dentry->d_inode->i_mapping->host;
656 	int ret;
657 
658 	mlog_entry_void();
659 
660 	/*
661 	 * Fallback to buffered I/O if we see an inode without
662 	 * extents.
663 	 */
664 	if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
665 		return 0;
666 
667 	/* Fallback to buffered I/O if we are appending. */
668 	if (i_size_read(inode) <= offset)
669 		return 0;
670 
671 	ret = blockdev_direct_IO_no_locking(rw, iocb, inode,
672 					    inode->i_sb->s_bdev, iov, offset,
673 					    nr_segs,
674 					    ocfs2_direct_IO_get_blocks,
675 					    ocfs2_dio_end_io);
676 
677 	mlog_exit(ret);
678 	return ret;
679 }
680 
681 static void ocfs2_figure_cluster_boundaries(struct ocfs2_super *osb,
682 					    u32 cpos,
683 					    unsigned int *start,
684 					    unsigned int *end)
685 {
686 	unsigned int cluster_start = 0, cluster_end = PAGE_CACHE_SIZE;
687 
688 	if (unlikely(PAGE_CACHE_SHIFT > osb->s_clustersize_bits)) {
689 		unsigned int cpp;
690 
691 		cpp = 1 << (PAGE_CACHE_SHIFT - osb->s_clustersize_bits);
692 
693 		cluster_start = cpos % cpp;
694 		cluster_start = cluster_start << osb->s_clustersize_bits;
695 
696 		cluster_end = cluster_start + osb->s_clustersize;
697 	}
698 
699 	BUG_ON(cluster_start > PAGE_SIZE);
700 	BUG_ON(cluster_end > PAGE_SIZE);
701 
702 	if (start)
703 		*start = cluster_start;
704 	if (end)
705 		*end = cluster_end;
706 }
707 
708 /*
709  * 'from' and 'to' are the region in the page to avoid zeroing.
710  *
711  * If pagesize > clustersize, this function will avoid zeroing outside
712  * of the cluster boundary.
713  *
714  * from == to == 0 is code for "zero the entire cluster region"
715  */
716 static void ocfs2_clear_page_regions(struct page *page,
717 				     struct ocfs2_super *osb, u32 cpos,
718 				     unsigned from, unsigned to)
719 {
720 	void *kaddr;
721 	unsigned int cluster_start, cluster_end;
722 
723 	ocfs2_figure_cluster_boundaries(osb, cpos, &cluster_start, &cluster_end);
724 
725 	kaddr = kmap_atomic(page, KM_USER0);
726 
727 	if (from || to) {
728 		if (from > cluster_start)
729 			memset(kaddr + cluster_start, 0, from - cluster_start);
730 		if (to < cluster_end)
731 			memset(kaddr + to, 0, cluster_end - to);
732 	} else {
733 		memset(kaddr + cluster_start, 0, cluster_end - cluster_start);
734 	}
735 
736 	kunmap_atomic(kaddr, KM_USER0);
737 }
738 
739 /*
740  * Nonsparse file systems fully allocate before we get to the write
741  * code. This prevents ocfs2_write() from tagging the write as an
742  * allocating one, which means ocfs2_map_page_blocks() might try to
743  * read-in the blocks at the tail of our file. Avoid reading them by
744  * testing i_size against each block offset.
745  */
746 static int ocfs2_should_read_blk(struct inode *inode, struct page *page,
747 				 unsigned int block_start)
748 {
749 	u64 offset = page_offset(page) + block_start;
750 
751 	if (ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb)))
752 		return 1;
753 
754 	if (i_size_read(inode) > offset)
755 		return 1;
756 
757 	return 0;
758 }
759 
760 /*
761  * Some of this taken from block_prepare_write(). We already have our
762  * mapping by now though, and the entire write will be allocating or
763  * it won't, so not much need to use BH_New.
764  *
765  * This will also skip zeroing, which is handled externally.
766  */
767 int ocfs2_map_page_blocks(struct page *page, u64 *p_blkno,
768 			  struct inode *inode, unsigned int from,
769 			  unsigned int to, int new)
770 {
771 	int ret = 0;
772 	struct buffer_head *head, *bh, *wait[2], **wait_bh = wait;
773 	unsigned int block_end, block_start;
774 	unsigned int bsize = 1 << inode->i_blkbits;
775 
776 	if (!page_has_buffers(page))
777 		create_empty_buffers(page, bsize, 0);
778 
779 	head = page_buffers(page);
780 	for (bh = head, block_start = 0; bh != head || !block_start;
781 	     bh = bh->b_this_page, block_start += bsize) {
782 		block_end = block_start + bsize;
783 
784 		clear_buffer_new(bh);
785 
786 		/*
787 		 * Ignore blocks outside of our i/o range -
788 		 * they may belong to unallocated clusters.
789 		 */
790 		if (block_start >= to || block_end <= from) {
791 			if (PageUptodate(page))
792 				set_buffer_uptodate(bh);
793 			continue;
794 		}
795 
796 		/*
797 		 * For an allocating write with cluster size >= page
798 		 * size, we always write the entire page.
799 		 */
800 		if (new)
801 			set_buffer_new(bh);
802 
803 		if (!buffer_mapped(bh)) {
804 			map_bh(bh, inode->i_sb, *p_blkno);
805 			unmap_underlying_metadata(bh->b_bdev, bh->b_blocknr);
806 		}
807 
808 		if (PageUptodate(page)) {
809 			if (!buffer_uptodate(bh))
810 				set_buffer_uptodate(bh);
811 		} else if (!buffer_uptodate(bh) && !buffer_delay(bh) &&
812 			   !buffer_new(bh) &&
813 			   ocfs2_should_read_blk(inode, page, block_start) &&
814 			   (block_start < from || block_end > to)) {
815 			ll_rw_block(READ, 1, &bh);
816 			*wait_bh++=bh;
817 		}
818 
819 		*p_blkno = *p_blkno + 1;
820 	}
821 
822 	/*
823 	 * If we issued read requests - let them complete.
824 	 */
825 	while(wait_bh > wait) {
826 		wait_on_buffer(*--wait_bh);
827 		if (!buffer_uptodate(*wait_bh))
828 			ret = -EIO;
829 	}
830 
831 	if (ret == 0 || !new)
832 		return ret;
833 
834 	/*
835 	 * If we get -EIO above, zero out any newly allocated blocks
836 	 * to avoid exposing stale data.
837 	 */
838 	bh = head;
839 	block_start = 0;
840 	do {
841 		block_end = block_start + bsize;
842 		if (block_end <= from)
843 			goto next_bh;
844 		if (block_start >= to)
845 			break;
846 
847 		zero_user(page, block_start, bh->b_size);
848 		set_buffer_uptodate(bh);
849 		mark_buffer_dirty(bh);
850 
851 next_bh:
852 		block_start = block_end;
853 		bh = bh->b_this_page;
854 	} while (bh != head);
855 
856 	return ret;
857 }
858 
859 #if (PAGE_CACHE_SIZE >= OCFS2_MAX_CLUSTERSIZE)
860 #define OCFS2_MAX_CTXT_PAGES	1
861 #else
862 #define OCFS2_MAX_CTXT_PAGES	(OCFS2_MAX_CLUSTERSIZE / PAGE_CACHE_SIZE)
863 #endif
864 
865 #define OCFS2_MAX_CLUSTERS_PER_PAGE	(PAGE_CACHE_SIZE / OCFS2_MIN_CLUSTERSIZE)
866 
867 /*
868  * Describe the state of a single cluster to be written to.
869  */
870 struct ocfs2_write_cluster_desc {
871 	u32		c_cpos;
872 	u32		c_phys;
873 	/*
874 	 * Give this a unique field because c_phys eventually gets
875 	 * filled.
876 	 */
877 	unsigned	c_new;
878 	unsigned	c_unwritten;
879 	unsigned	c_needs_zero;
880 };
881 
882 struct ocfs2_write_ctxt {
883 	/* Logical cluster position / len of write */
884 	u32				w_cpos;
885 	u32				w_clen;
886 
887 	/* First cluster allocated in a nonsparse extend */
888 	u32				w_first_new_cpos;
889 
890 	struct ocfs2_write_cluster_desc	w_desc[OCFS2_MAX_CLUSTERS_PER_PAGE];
891 
892 	/*
893 	 * This is true if page_size > cluster_size.
894 	 *
895 	 * It triggers a set of special cases during write which might
896 	 * have to deal with allocating writes to partial pages.
897 	 */
898 	unsigned int			w_large_pages;
899 
900 	/*
901 	 * Pages involved in this write.
902 	 *
903 	 * w_target_page is the page being written to by the user.
904 	 *
905 	 * w_pages is an array of pages which always contains
906 	 * w_target_page, and in the case of an allocating write with
907 	 * page_size < cluster size, it will contain zero'd and mapped
908 	 * pages adjacent to w_target_page which need to be written
909 	 * out in so that future reads from that region will get
910 	 * zero's.
911 	 */
912 	struct page			*w_pages[OCFS2_MAX_CTXT_PAGES];
913 	unsigned int			w_num_pages;
914 	struct page			*w_target_page;
915 
916 	/*
917 	 * ocfs2_write_end() uses this to know what the real range to
918 	 * write in the target should be.
919 	 */
920 	unsigned int			w_target_from;
921 	unsigned int			w_target_to;
922 
923 	/*
924 	 * We could use journal_current_handle() but this is cleaner,
925 	 * IMHO -Mark
926 	 */
927 	handle_t			*w_handle;
928 
929 	struct buffer_head		*w_di_bh;
930 
931 	struct ocfs2_cached_dealloc_ctxt w_dealloc;
932 };
933 
934 void ocfs2_unlock_and_free_pages(struct page **pages, int num_pages)
935 {
936 	int i;
937 
938 	for(i = 0; i < num_pages; i++) {
939 		if (pages[i]) {
940 			unlock_page(pages[i]);
941 			mark_page_accessed(pages[i]);
942 			page_cache_release(pages[i]);
943 		}
944 	}
945 }
946 
947 static void ocfs2_free_write_ctxt(struct ocfs2_write_ctxt *wc)
948 {
949 	ocfs2_unlock_and_free_pages(wc->w_pages, wc->w_num_pages);
950 
951 	brelse(wc->w_di_bh);
952 	kfree(wc);
953 }
954 
955 static int ocfs2_alloc_write_ctxt(struct ocfs2_write_ctxt **wcp,
956 				  struct ocfs2_super *osb, loff_t pos,
957 				  unsigned len, struct buffer_head *di_bh)
958 {
959 	u32 cend;
960 	struct ocfs2_write_ctxt *wc;
961 
962 	wc = kzalloc(sizeof(struct ocfs2_write_ctxt), GFP_NOFS);
963 	if (!wc)
964 		return -ENOMEM;
965 
966 	wc->w_cpos = pos >> osb->s_clustersize_bits;
967 	wc->w_first_new_cpos = UINT_MAX;
968 	cend = (pos + len - 1) >> osb->s_clustersize_bits;
969 	wc->w_clen = cend - wc->w_cpos + 1;
970 	get_bh(di_bh);
971 	wc->w_di_bh = di_bh;
972 
973 	if (unlikely(PAGE_CACHE_SHIFT > osb->s_clustersize_bits))
974 		wc->w_large_pages = 1;
975 	else
976 		wc->w_large_pages = 0;
977 
978 	ocfs2_init_dealloc_ctxt(&wc->w_dealloc);
979 
980 	*wcp = wc;
981 
982 	return 0;
983 }
984 
985 /*
986  * If a page has any new buffers, zero them out here, and mark them uptodate
987  * and dirty so they'll be written out (in order to prevent uninitialised
988  * block data from leaking). And clear the new bit.
989  */
990 static void ocfs2_zero_new_buffers(struct page *page, unsigned from, unsigned to)
991 {
992 	unsigned int block_start, block_end;
993 	struct buffer_head *head, *bh;
994 
995 	BUG_ON(!PageLocked(page));
996 	if (!page_has_buffers(page))
997 		return;
998 
999 	bh = head = page_buffers(page);
1000 	block_start = 0;
1001 	do {
1002 		block_end = block_start + bh->b_size;
1003 
1004 		if (buffer_new(bh)) {
1005 			if (block_end > from && block_start < to) {
1006 				if (!PageUptodate(page)) {
1007 					unsigned start, end;
1008 
1009 					start = max(from, block_start);
1010 					end = min(to, block_end);
1011 
1012 					zero_user_segment(page, start, end);
1013 					set_buffer_uptodate(bh);
1014 				}
1015 
1016 				clear_buffer_new(bh);
1017 				mark_buffer_dirty(bh);
1018 			}
1019 		}
1020 
1021 		block_start = block_end;
1022 		bh = bh->b_this_page;
1023 	} while (bh != head);
1024 }
1025 
1026 /*
1027  * Only called when we have a failure during allocating write to write
1028  * zero's to the newly allocated region.
1029  */
1030 static void ocfs2_write_failure(struct inode *inode,
1031 				struct ocfs2_write_ctxt *wc,
1032 				loff_t user_pos, unsigned user_len)
1033 {
1034 	int i;
1035 	unsigned from = user_pos & (PAGE_CACHE_SIZE - 1),
1036 		to = user_pos + user_len;
1037 	struct page *tmppage;
1038 
1039 	ocfs2_zero_new_buffers(wc->w_target_page, from, to);
1040 
1041 	for(i = 0; i < wc->w_num_pages; i++) {
1042 		tmppage = wc->w_pages[i];
1043 
1044 		if (page_has_buffers(tmppage)) {
1045 			if (ocfs2_should_order_data(inode))
1046 				ocfs2_jbd2_file_inode(wc->w_handle, inode);
1047 
1048 			block_commit_write(tmppage, from, to);
1049 		}
1050 	}
1051 }
1052 
1053 static int ocfs2_prepare_page_for_write(struct inode *inode, u64 *p_blkno,
1054 					struct ocfs2_write_ctxt *wc,
1055 					struct page *page, u32 cpos,
1056 					loff_t user_pos, unsigned user_len,
1057 					int new)
1058 {
1059 	int ret;
1060 	unsigned int map_from = 0, map_to = 0;
1061 	unsigned int cluster_start, cluster_end;
1062 	unsigned int user_data_from = 0, user_data_to = 0;
1063 
1064 	ocfs2_figure_cluster_boundaries(OCFS2_SB(inode->i_sb), cpos,
1065 					&cluster_start, &cluster_end);
1066 
1067 	if (page == wc->w_target_page) {
1068 		map_from = user_pos & (PAGE_CACHE_SIZE - 1);
1069 		map_to = map_from + user_len;
1070 
1071 		if (new)
1072 			ret = ocfs2_map_page_blocks(page, p_blkno, inode,
1073 						    cluster_start, cluster_end,
1074 						    new);
1075 		else
1076 			ret = ocfs2_map_page_blocks(page, p_blkno, inode,
1077 						    map_from, map_to, new);
1078 		if (ret) {
1079 			mlog_errno(ret);
1080 			goto out;
1081 		}
1082 
1083 		user_data_from = map_from;
1084 		user_data_to = map_to;
1085 		if (new) {
1086 			map_from = cluster_start;
1087 			map_to = cluster_end;
1088 		}
1089 	} else {
1090 		/*
1091 		 * If we haven't allocated the new page yet, we
1092 		 * shouldn't be writing it out without copying user
1093 		 * data. This is likely a math error from the caller.
1094 		 */
1095 		BUG_ON(!new);
1096 
1097 		map_from = cluster_start;
1098 		map_to = cluster_end;
1099 
1100 		ret = ocfs2_map_page_blocks(page, p_blkno, inode,
1101 					    cluster_start, cluster_end, new);
1102 		if (ret) {
1103 			mlog_errno(ret);
1104 			goto out;
1105 		}
1106 	}
1107 
1108 	/*
1109 	 * Parts of newly allocated pages need to be zero'd.
1110 	 *
1111 	 * Above, we have also rewritten 'to' and 'from' - as far as
1112 	 * the rest of the function is concerned, the entire cluster
1113 	 * range inside of a page needs to be written.
1114 	 *
1115 	 * We can skip this if the page is up to date - it's already
1116 	 * been zero'd from being read in as a hole.
1117 	 */
1118 	if (new && !PageUptodate(page))
1119 		ocfs2_clear_page_regions(page, OCFS2_SB(inode->i_sb),
1120 					 cpos, user_data_from, user_data_to);
1121 
1122 	flush_dcache_page(page);
1123 
1124 out:
1125 	return ret;
1126 }
1127 
1128 /*
1129  * This function will only grab one clusters worth of pages.
1130  */
1131 static int ocfs2_grab_pages_for_write(struct address_space *mapping,
1132 				      struct ocfs2_write_ctxt *wc,
1133 				      u32 cpos, loff_t user_pos, int new,
1134 				      struct page *mmap_page)
1135 {
1136 	int ret = 0, i;
1137 	unsigned long start, target_index, index;
1138 	struct inode *inode = mapping->host;
1139 
1140 	target_index = user_pos >> PAGE_CACHE_SHIFT;
1141 
1142 	/*
1143 	 * Figure out how many pages we'll be manipulating here. For
1144 	 * non allocating write, we just change the one
1145 	 * page. Otherwise, we'll need a whole clusters worth.
1146 	 */
1147 	if (new) {
1148 		wc->w_num_pages = ocfs2_pages_per_cluster(inode->i_sb);
1149 		start = ocfs2_align_clusters_to_page_index(inode->i_sb, cpos);
1150 	} else {
1151 		wc->w_num_pages = 1;
1152 		start = target_index;
1153 	}
1154 
1155 	for(i = 0; i < wc->w_num_pages; i++) {
1156 		index = start + i;
1157 
1158 		if (index == target_index && mmap_page) {
1159 			/*
1160 			 * ocfs2_pagemkwrite() is a little different
1161 			 * and wants us to directly use the page
1162 			 * passed in.
1163 			 */
1164 			lock_page(mmap_page);
1165 
1166 			if (mmap_page->mapping != mapping) {
1167 				unlock_page(mmap_page);
1168 				/*
1169 				 * Sanity check - the locking in
1170 				 * ocfs2_pagemkwrite() should ensure
1171 				 * that this code doesn't trigger.
1172 				 */
1173 				ret = -EINVAL;
1174 				mlog_errno(ret);
1175 				goto out;
1176 			}
1177 
1178 			page_cache_get(mmap_page);
1179 			wc->w_pages[i] = mmap_page;
1180 		} else {
1181 			wc->w_pages[i] = find_or_create_page(mapping, index,
1182 							     GFP_NOFS);
1183 			if (!wc->w_pages[i]) {
1184 				ret = -ENOMEM;
1185 				mlog_errno(ret);
1186 				goto out;
1187 			}
1188 		}
1189 
1190 		if (index == target_index)
1191 			wc->w_target_page = wc->w_pages[i];
1192 	}
1193 out:
1194 	return ret;
1195 }
1196 
1197 /*
1198  * Prepare a single cluster for write one cluster into the file.
1199  */
1200 static int ocfs2_write_cluster(struct address_space *mapping,
1201 			       u32 phys, unsigned int unwritten,
1202 			       unsigned int should_zero,
1203 			       struct ocfs2_alloc_context *data_ac,
1204 			       struct ocfs2_alloc_context *meta_ac,
1205 			       struct ocfs2_write_ctxt *wc, u32 cpos,
1206 			       loff_t user_pos, unsigned user_len)
1207 {
1208 	int ret, i, new;
1209 	u64 v_blkno, p_blkno;
1210 	struct inode *inode = mapping->host;
1211 	struct ocfs2_extent_tree et;
1212 
1213 	new = phys == 0 ? 1 : 0;
1214 	if (new) {
1215 		u32 tmp_pos;
1216 
1217 		/*
1218 		 * This is safe to call with the page locks - it won't take
1219 		 * any additional semaphores or cluster locks.
1220 		 */
1221 		tmp_pos = cpos;
1222 		ret = ocfs2_add_inode_data(OCFS2_SB(inode->i_sb), inode,
1223 					   &tmp_pos, 1, 0, wc->w_di_bh,
1224 					   wc->w_handle, data_ac,
1225 					   meta_ac, NULL);
1226 		/*
1227 		 * This shouldn't happen because we must have already
1228 		 * calculated the correct meta data allocation required. The
1229 		 * internal tree allocation code should know how to increase
1230 		 * transaction credits itself.
1231 		 *
1232 		 * If need be, we could handle -EAGAIN for a
1233 		 * RESTART_TRANS here.
1234 		 */
1235 		mlog_bug_on_msg(ret == -EAGAIN,
1236 				"Inode %llu: EAGAIN return during allocation.\n",
1237 				(unsigned long long)OCFS2_I(inode)->ip_blkno);
1238 		if (ret < 0) {
1239 			mlog_errno(ret);
1240 			goto out;
1241 		}
1242 	} else if (unwritten) {
1243 		ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode),
1244 					      wc->w_di_bh);
1245 		ret = ocfs2_mark_extent_written(inode, &et,
1246 						wc->w_handle, cpos, 1, phys,
1247 						meta_ac, &wc->w_dealloc);
1248 		if (ret < 0) {
1249 			mlog_errno(ret);
1250 			goto out;
1251 		}
1252 	}
1253 
1254 	if (should_zero)
1255 		v_blkno = ocfs2_clusters_to_blocks(inode->i_sb, cpos);
1256 	else
1257 		v_blkno = user_pos >> inode->i_sb->s_blocksize_bits;
1258 
1259 	/*
1260 	 * The only reason this should fail is due to an inability to
1261 	 * find the extent added.
1262 	 */
1263 	ret = ocfs2_extent_map_get_blocks(inode, v_blkno, &p_blkno, NULL,
1264 					  NULL);
1265 	if (ret < 0) {
1266 		ocfs2_error(inode->i_sb, "Corrupting extend for inode %llu, "
1267 			    "at logical block %llu",
1268 			    (unsigned long long)OCFS2_I(inode)->ip_blkno,
1269 			    (unsigned long long)v_blkno);
1270 		goto out;
1271 	}
1272 
1273 	BUG_ON(p_blkno == 0);
1274 
1275 	for(i = 0; i < wc->w_num_pages; i++) {
1276 		int tmpret;
1277 
1278 		tmpret = ocfs2_prepare_page_for_write(inode, &p_blkno, wc,
1279 						      wc->w_pages[i], cpos,
1280 						      user_pos, user_len,
1281 						      should_zero);
1282 		if (tmpret) {
1283 			mlog_errno(tmpret);
1284 			if (ret == 0)
1285 				ret = tmpret;
1286 		}
1287 	}
1288 
1289 	/*
1290 	 * We only have cleanup to do in case of allocating write.
1291 	 */
1292 	if (ret && new)
1293 		ocfs2_write_failure(inode, wc, user_pos, user_len);
1294 
1295 out:
1296 
1297 	return ret;
1298 }
1299 
1300 static int ocfs2_write_cluster_by_desc(struct address_space *mapping,
1301 				       struct ocfs2_alloc_context *data_ac,
1302 				       struct ocfs2_alloc_context *meta_ac,
1303 				       struct ocfs2_write_ctxt *wc,
1304 				       loff_t pos, unsigned len)
1305 {
1306 	int ret, i;
1307 	loff_t cluster_off;
1308 	unsigned int local_len = len;
1309 	struct ocfs2_write_cluster_desc *desc;
1310 	struct ocfs2_super *osb = OCFS2_SB(mapping->host->i_sb);
1311 
1312 	for (i = 0; i < wc->w_clen; i++) {
1313 		desc = &wc->w_desc[i];
1314 
1315 		/*
1316 		 * We have to make sure that the total write passed in
1317 		 * doesn't extend past a single cluster.
1318 		 */
1319 		local_len = len;
1320 		cluster_off = pos & (osb->s_clustersize - 1);
1321 		if ((cluster_off + local_len) > osb->s_clustersize)
1322 			local_len = osb->s_clustersize - cluster_off;
1323 
1324 		ret = ocfs2_write_cluster(mapping, desc->c_phys,
1325 					  desc->c_unwritten,
1326 					  desc->c_needs_zero,
1327 					  data_ac, meta_ac,
1328 					  wc, desc->c_cpos, pos, local_len);
1329 		if (ret) {
1330 			mlog_errno(ret);
1331 			goto out;
1332 		}
1333 
1334 		len -= local_len;
1335 		pos += local_len;
1336 	}
1337 
1338 	ret = 0;
1339 out:
1340 	return ret;
1341 }
1342 
1343 /*
1344  * ocfs2_write_end() wants to know which parts of the target page it
1345  * should complete the write on. It's easiest to compute them ahead of
1346  * time when a more complete view of the write is available.
1347  */
1348 static void ocfs2_set_target_boundaries(struct ocfs2_super *osb,
1349 					struct ocfs2_write_ctxt *wc,
1350 					loff_t pos, unsigned len, int alloc)
1351 {
1352 	struct ocfs2_write_cluster_desc *desc;
1353 
1354 	wc->w_target_from = pos & (PAGE_CACHE_SIZE - 1);
1355 	wc->w_target_to = wc->w_target_from + len;
1356 
1357 	if (alloc == 0)
1358 		return;
1359 
1360 	/*
1361 	 * Allocating write - we may have different boundaries based
1362 	 * on page size and cluster size.
1363 	 *
1364 	 * NOTE: We can no longer compute one value from the other as
1365 	 * the actual write length and user provided length may be
1366 	 * different.
1367 	 */
1368 
1369 	if (wc->w_large_pages) {
1370 		/*
1371 		 * We only care about the 1st and last cluster within
1372 		 * our range and whether they should be zero'd or not. Either
1373 		 * value may be extended out to the start/end of a
1374 		 * newly allocated cluster.
1375 		 */
1376 		desc = &wc->w_desc[0];
1377 		if (desc->c_needs_zero)
1378 			ocfs2_figure_cluster_boundaries(osb,
1379 							desc->c_cpos,
1380 							&wc->w_target_from,
1381 							NULL);
1382 
1383 		desc = &wc->w_desc[wc->w_clen - 1];
1384 		if (desc->c_needs_zero)
1385 			ocfs2_figure_cluster_boundaries(osb,
1386 							desc->c_cpos,
1387 							NULL,
1388 							&wc->w_target_to);
1389 	} else {
1390 		wc->w_target_from = 0;
1391 		wc->w_target_to = PAGE_CACHE_SIZE;
1392 	}
1393 }
1394 
1395 /*
1396  * Populate each single-cluster write descriptor in the write context
1397  * with information about the i/o to be done.
1398  *
1399  * Returns the number of clusters that will have to be allocated, as
1400  * well as a worst case estimate of the number of extent records that
1401  * would have to be created during a write to an unwritten region.
1402  */
1403 static int ocfs2_populate_write_desc(struct inode *inode,
1404 				     struct ocfs2_write_ctxt *wc,
1405 				     unsigned int *clusters_to_alloc,
1406 				     unsigned int *extents_to_split)
1407 {
1408 	int ret;
1409 	struct ocfs2_write_cluster_desc *desc;
1410 	unsigned int num_clusters = 0;
1411 	unsigned int ext_flags = 0;
1412 	u32 phys = 0;
1413 	int i;
1414 
1415 	*clusters_to_alloc = 0;
1416 	*extents_to_split = 0;
1417 
1418 	for (i = 0; i < wc->w_clen; i++) {
1419 		desc = &wc->w_desc[i];
1420 		desc->c_cpos = wc->w_cpos + i;
1421 
1422 		if (num_clusters == 0) {
1423 			/*
1424 			 * Need to look up the next extent record.
1425 			 */
1426 			ret = ocfs2_get_clusters(inode, desc->c_cpos, &phys,
1427 						 &num_clusters, &ext_flags);
1428 			if (ret) {
1429 				mlog_errno(ret);
1430 				goto out;
1431 			}
1432 
1433 			/* We should already CoW the refcountd extent. */
1434 			BUG_ON(ext_flags & OCFS2_EXT_REFCOUNTED);
1435 
1436 			/*
1437 			 * Assume worst case - that we're writing in
1438 			 * the middle of the extent.
1439 			 *
1440 			 * We can assume that the write proceeds from
1441 			 * left to right, in which case the extent
1442 			 * insert code is smart enough to coalesce the
1443 			 * next splits into the previous records created.
1444 			 */
1445 			if (ext_flags & OCFS2_EXT_UNWRITTEN)
1446 				*extents_to_split = *extents_to_split + 2;
1447 		} else if (phys) {
1448 			/*
1449 			 * Only increment phys if it doesn't describe
1450 			 * a hole.
1451 			 */
1452 			phys++;
1453 		}
1454 
1455 		/*
1456 		 * If w_first_new_cpos is < UINT_MAX, we have a non-sparse
1457 		 * file that got extended.  w_first_new_cpos tells us
1458 		 * where the newly allocated clusters are so we can
1459 		 * zero them.
1460 		 */
1461 		if (desc->c_cpos >= wc->w_first_new_cpos) {
1462 			BUG_ON(phys == 0);
1463 			desc->c_needs_zero = 1;
1464 		}
1465 
1466 		desc->c_phys = phys;
1467 		if (phys == 0) {
1468 			desc->c_new = 1;
1469 			desc->c_needs_zero = 1;
1470 			*clusters_to_alloc = *clusters_to_alloc + 1;
1471 		}
1472 
1473 		if (ext_flags & OCFS2_EXT_UNWRITTEN) {
1474 			desc->c_unwritten = 1;
1475 			desc->c_needs_zero = 1;
1476 		}
1477 
1478 		num_clusters--;
1479 	}
1480 
1481 	ret = 0;
1482 out:
1483 	return ret;
1484 }
1485 
1486 static int ocfs2_write_begin_inline(struct address_space *mapping,
1487 				    struct inode *inode,
1488 				    struct ocfs2_write_ctxt *wc)
1489 {
1490 	int ret;
1491 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1492 	struct page *page;
1493 	handle_t *handle;
1494 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)wc->w_di_bh->b_data;
1495 
1496 	page = find_or_create_page(mapping, 0, GFP_NOFS);
1497 	if (!page) {
1498 		ret = -ENOMEM;
1499 		mlog_errno(ret);
1500 		goto out;
1501 	}
1502 	/*
1503 	 * If we don't set w_num_pages then this page won't get unlocked
1504 	 * and freed on cleanup of the write context.
1505 	 */
1506 	wc->w_pages[0] = wc->w_target_page = page;
1507 	wc->w_num_pages = 1;
1508 
1509 	handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
1510 	if (IS_ERR(handle)) {
1511 		ret = PTR_ERR(handle);
1512 		mlog_errno(ret);
1513 		goto out;
1514 	}
1515 
1516 	ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), wc->w_di_bh,
1517 				      OCFS2_JOURNAL_ACCESS_WRITE);
1518 	if (ret) {
1519 		ocfs2_commit_trans(osb, handle);
1520 
1521 		mlog_errno(ret);
1522 		goto out;
1523 	}
1524 
1525 	if (!(OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL))
1526 		ocfs2_set_inode_data_inline(inode, di);
1527 
1528 	if (!PageUptodate(page)) {
1529 		ret = ocfs2_read_inline_data(inode, page, wc->w_di_bh);
1530 		if (ret) {
1531 			ocfs2_commit_trans(osb, handle);
1532 
1533 			goto out;
1534 		}
1535 	}
1536 
1537 	wc->w_handle = handle;
1538 out:
1539 	return ret;
1540 }
1541 
1542 int ocfs2_size_fits_inline_data(struct buffer_head *di_bh, u64 new_size)
1543 {
1544 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
1545 
1546 	if (new_size <= le16_to_cpu(di->id2.i_data.id_count))
1547 		return 1;
1548 	return 0;
1549 }
1550 
1551 static int ocfs2_try_to_write_inline_data(struct address_space *mapping,
1552 					  struct inode *inode, loff_t pos,
1553 					  unsigned len, struct page *mmap_page,
1554 					  struct ocfs2_write_ctxt *wc)
1555 {
1556 	int ret, written = 0;
1557 	loff_t end = pos + len;
1558 	struct ocfs2_inode_info *oi = OCFS2_I(inode);
1559 	struct ocfs2_dinode *di = NULL;
1560 
1561 	mlog(0, "Inode %llu, write of %u bytes at off %llu. features: 0x%x\n",
1562 	     (unsigned long long)oi->ip_blkno, len, (unsigned long long)pos,
1563 	     oi->ip_dyn_features);
1564 
1565 	/*
1566 	 * Handle inodes which already have inline data 1st.
1567 	 */
1568 	if (oi->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
1569 		if (mmap_page == NULL &&
1570 		    ocfs2_size_fits_inline_data(wc->w_di_bh, end))
1571 			goto do_inline_write;
1572 
1573 		/*
1574 		 * The write won't fit - we have to give this inode an
1575 		 * inline extent list now.
1576 		 */
1577 		ret = ocfs2_convert_inline_data_to_extents(inode, wc->w_di_bh);
1578 		if (ret)
1579 			mlog_errno(ret);
1580 		goto out;
1581 	}
1582 
1583 	/*
1584 	 * Check whether the inode can accept inline data.
1585 	 */
1586 	if (oi->ip_clusters != 0 || i_size_read(inode) != 0)
1587 		return 0;
1588 
1589 	/*
1590 	 * Check whether the write can fit.
1591 	 */
1592 	di = (struct ocfs2_dinode *)wc->w_di_bh->b_data;
1593 	if (mmap_page ||
1594 	    end > ocfs2_max_inline_data_with_xattr(inode->i_sb, di))
1595 		return 0;
1596 
1597 do_inline_write:
1598 	ret = ocfs2_write_begin_inline(mapping, inode, wc);
1599 	if (ret) {
1600 		mlog_errno(ret);
1601 		goto out;
1602 	}
1603 
1604 	/*
1605 	 * This signals to the caller that the data can be written
1606 	 * inline.
1607 	 */
1608 	written = 1;
1609 out:
1610 	return written ? written : ret;
1611 }
1612 
1613 /*
1614  * This function only does anything for file systems which can't
1615  * handle sparse files.
1616  *
1617  * What we want to do here is fill in any hole between the current end
1618  * of allocation and the end of our write. That way the rest of the
1619  * write path can treat it as an non-allocating write, which has no
1620  * special case code for sparse/nonsparse files.
1621  */
1622 static int ocfs2_expand_nonsparse_inode(struct inode *inode, loff_t pos,
1623 					unsigned len,
1624 					struct ocfs2_write_ctxt *wc)
1625 {
1626 	int ret;
1627 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1628 	loff_t newsize = pos + len;
1629 
1630 	if (ocfs2_sparse_alloc(osb))
1631 		return 0;
1632 
1633 	if (newsize <= i_size_read(inode))
1634 		return 0;
1635 
1636 	ret = ocfs2_extend_no_holes(inode, newsize, pos);
1637 	if (ret)
1638 		mlog_errno(ret);
1639 
1640 	wc->w_first_new_cpos =
1641 		ocfs2_clusters_for_bytes(inode->i_sb, i_size_read(inode));
1642 
1643 	return ret;
1644 }
1645 
1646 int ocfs2_write_begin_nolock(struct address_space *mapping,
1647 			     loff_t pos, unsigned len, unsigned flags,
1648 			     struct page **pagep, void **fsdata,
1649 			     struct buffer_head *di_bh, struct page *mmap_page)
1650 {
1651 	int ret, cluster_of_pages, credits = OCFS2_INODE_UPDATE_CREDITS;
1652 	unsigned int clusters_to_alloc, extents_to_split;
1653 	struct ocfs2_write_ctxt *wc;
1654 	struct inode *inode = mapping->host;
1655 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1656 	struct ocfs2_dinode *di;
1657 	struct ocfs2_alloc_context *data_ac = NULL;
1658 	struct ocfs2_alloc_context *meta_ac = NULL;
1659 	handle_t *handle;
1660 	struct ocfs2_extent_tree et;
1661 
1662 	ret = ocfs2_alloc_write_ctxt(&wc, osb, pos, len, di_bh);
1663 	if (ret) {
1664 		mlog_errno(ret);
1665 		return ret;
1666 	}
1667 
1668 	if (ocfs2_supports_inline_data(osb)) {
1669 		ret = ocfs2_try_to_write_inline_data(mapping, inode, pos, len,
1670 						     mmap_page, wc);
1671 		if (ret == 1) {
1672 			ret = 0;
1673 			goto success;
1674 		}
1675 		if (ret < 0) {
1676 			mlog_errno(ret);
1677 			goto out;
1678 		}
1679 	}
1680 
1681 	ret = ocfs2_expand_nonsparse_inode(inode, pos, len, wc);
1682 	if (ret) {
1683 		mlog_errno(ret);
1684 		goto out;
1685 	}
1686 
1687 	ret = ocfs2_check_range_for_refcount(inode, pos, len);
1688 	if (ret < 0) {
1689 		mlog_errno(ret);
1690 		goto out;
1691 	} else if (ret == 1) {
1692 		ret = ocfs2_refcount_cow(inode, di_bh,
1693 					 wc->w_cpos, wc->w_clen, UINT_MAX);
1694 		if (ret) {
1695 			mlog_errno(ret);
1696 			goto out;
1697 		}
1698 	}
1699 
1700 	ret = ocfs2_populate_write_desc(inode, wc, &clusters_to_alloc,
1701 					&extents_to_split);
1702 	if (ret) {
1703 		mlog_errno(ret);
1704 		goto out;
1705 	}
1706 
1707 	di = (struct ocfs2_dinode *)wc->w_di_bh->b_data;
1708 
1709 	/*
1710 	 * We set w_target_from, w_target_to here so that
1711 	 * ocfs2_write_end() knows which range in the target page to
1712 	 * write out. An allocation requires that we write the entire
1713 	 * cluster range.
1714 	 */
1715 	if (clusters_to_alloc || extents_to_split) {
1716 		/*
1717 		 * XXX: We are stretching the limits of
1718 		 * ocfs2_lock_allocators(). It greatly over-estimates
1719 		 * the work to be done.
1720 		 */
1721 		mlog(0, "extend inode %llu, i_size = %lld, di->i_clusters = %u,"
1722 		     " clusters_to_add = %u, extents_to_split = %u\n",
1723 		     (unsigned long long)OCFS2_I(inode)->ip_blkno,
1724 		     (long long)i_size_read(inode), le32_to_cpu(di->i_clusters),
1725 		     clusters_to_alloc, extents_to_split);
1726 
1727 		ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode),
1728 					      wc->w_di_bh);
1729 		ret = ocfs2_lock_allocators(inode, &et,
1730 					    clusters_to_alloc, extents_to_split,
1731 					    &data_ac, &meta_ac);
1732 		if (ret) {
1733 			mlog_errno(ret);
1734 			goto out;
1735 		}
1736 
1737 		credits = ocfs2_calc_extend_credits(inode->i_sb,
1738 						    &di->id2.i_list,
1739 						    clusters_to_alloc);
1740 
1741 	}
1742 
1743 	/*
1744 	 * We have to zero sparse allocated clusters, unwritten extent clusters,
1745 	 * and non-sparse clusters we just extended.  For non-sparse writes,
1746 	 * we know zeros will only be needed in the first and/or last cluster.
1747 	 */
1748 	if (clusters_to_alloc || extents_to_split ||
1749 	    (wc->w_clen && (wc->w_desc[0].c_needs_zero ||
1750 			    wc->w_desc[wc->w_clen - 1].c_needs_zero)))
1751 		cluster_of_pages = 1;
1752 	else
1753 		cluster_of_pages = 0;
1754 
1755 	ocfs2_set_target_boundaries(osb, wc, pos, len, cluster_of_pages);
1756 
1757 	handle = ocfs2_start_trans(osb, credits);
1758 	if (IS_ERR(handle)) {
1759 		ret = PTR_ERR(handle);
1760 		mlog_errno(ret);
1761 		goto out;
1762 	}
1763 
1764 	wc->w_handle = handle;
1765 
1766 	if (clusters_to_alloc && vfs_dq_alloc_space_nodirty(inode,
1767 			ocfs2_clusters_to_bytes(osb->sb, clusters_to_alloc))) {
1768 		ret = -EDQUOT;
1769 		goto out_commit;
1770 	}
1771 	/*
1772 	 * We don't want this to fail in ocfs2_write_end(), so do it
1773 	 * here.
1774 	 */
1775 	ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), wc->w_di_bh,
1776 				      OCFS2_JOURNAL_ACCESS_WRITE);
1777 	if (ret) {
1778 		mlog_errno(ret);
1779 		goto out_quota;
1780 	}
1781 
1782 	/*
1783 	 * Fill our page array first. That way we've grabbed enough so
1784 	 * that we can zero and flush if we error after adding the
1785 	 * extent.
1786 	 */
1787 	ret = ocfs2_grab_pages_for_write(mapping, wc, wc->w_cpos, pos,
1788 					 cluster_of_pages, mmap_page);
1789 	if (ret) {
1790 		mlog_errno(ret);
1791 		goto out_quota;
1792 	}
1793 
1794 	ret = ocfs2_write_cluster_by_desc(mapping, data_ac, meta_ac, wc, pos,
1795 					  len);
1796 	if (ret) {
1797 		mlog_errno(ret);
1798 		goto out_quota;
1799 	}
1800 
1801 	if (data_ac)
1802 		ocfs2_free_alloc_context(data_ac);
1803 	if (meta_ac)
1804 		ocfs2_free_alloc_context(meta_ac);
1805 
1806 success:
1807 	*pagep = wc->w_target_page;
1808 	*fsdata = wc;
1809 	return 0;
1810 out_quota:
1811 	if (clusters_to_alloc)
1812 		vfs_dq_free_space(inode,
1813 			  ocfs2_clusters_to_bytes(osb->sb, clusters_to_alloc));
1814 out_commit:
1815 	ocfs2_commit_trans(osb, handle);
1816 
1817 out:
1818 	ocfs2_free_write_ctxt(wc);
1819 
1820 	if (data_ac)
1821 		ocfs2_free_alloc_context(data_ac);
1822 	if (meta_ac)
1823 		ocfs2_free_alloc_context(meta_ac);
1824 	return ret;
1825 }
1826 
1827 static int ocfs2_write_begin(struct file *file, struct address_space *mapping,
1828 			     loff_t pos, unsigned len, unsigned flags,
1829 			     struct page **pagep, void **fsdata)
1830 {
1831 	int ret;
1832 	struct buffer_head *di_bh = NULL;
1833 	struct inode *inode = mapping->host;
1834 
1835 	ret = ocfs2_inode_lock(inode, &di_bh, 1);
1836 	if (ret) {
1837 		mlog_errno(ret);
1838 		return ret;
1839 	}
1840 
1841 	/*
1842 	 * Take alloc sem here to prevent concurrent lookups. That way
1843 	 * the mapping, zeroing and tree manipulation within
1844 	 * ocfs2_write() will be safe against ->readpage(). This
1845 	 * should also serve to lock out allocation from a shared
1846 	 * writeable region.
1847 	 */
1848 	down_write(&OCFS2_I(inode)->ip_alloc_sem);
1849 
1850 	ret = ocfs2_write_begin_nolock(mapping, pos, len, flags, pagep,
1851 				       fsdata, di_bh, NULL);
1852 	if (ret) {
1853 		mlog_errno(ret);
1854 		goto out_fail;
1855 	}
1856 
1857 	brelse(di_bh);
1858 
1859 	return 0;
1860 
1861 out_fail:
1862 	up_write(&OCFS2_I(inode)->ip_alloc_sem);
1863 
1864 	brelse(di_bh);
1865 	ocfs2_inode_unlock(inode, 1);
1866 
1867 	return ret;
1868 }
1869 
1870 static void ocfs2_write_end_inline(struct inode *inode, loff_t pos,
1871 				   unsigned len, unsigned *copied,
1872 				   struct ocfs2_dinode *di,
1873 				   struct ocfs2_write_ctxt *wc)
1874 {
1875 	void *kaddr;
1876 
1877 	if (unlikely(*copied < len)) {
1878 		if (!PageUptodate(wc->w_target_page)) {
1879 			*copied = 0;
1880 			return;
1881 		}
1882 	}
1883 
1884 	kaddr = kmap_atomic(wc->w_target_page, KM_USER0);
1885 	memcpy(di->id2.i_data.id_data + pos, kaddr + pos, *copied);
1886 	kunmap_atomic(kaddr, KM_USER0);
1887 
1888 	mlog(0, "Data written to inode at offset %llu. "
1889 	     "id_count = %u, copied = %u, i_dyn_features = 0x%x\n",
1890 	     (unsigned long long)pos, *copied,
1891 	     le16_to_cpu(di->id2.i_data.id_count),
1892 	     le16_to_cpu(di->i_dyn_features));
1893 }
1894 
1895 int ocfs2_write_end_nolock(struct address_space *mapping,
1896 			   loff_t pos, unsigned len, unsigned copied,
1897 			   struct page *page, void *fsdata)
1898 {
1899 	int i;
1900 	unsigned from, to, start = pos & (PAGE_CACHE_SIZE - 1);
1901 	struct inode *inode = mapping->host;
1902 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1903 	struct ocfs2_write_ctxt *wc = fsdata;
1904 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)wc->w_di_bh->b_data;
1905 	handle_t *handle = wc->w_handle;
1906 	struct page *tmppage;
1907 
1908 	if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
1909 		ocfs2_write_end_inline(inode, pos, len, &copied, di, wc);
1910 		goto out_write_size;
1911 	}
1912 
1913 	if (unlikely(copied < len)) {
1914 		if (!PageUptodate(wc->w_target_page))
1915 			copied = 0;
1916 
1917 		ocfs2_zero_new_buffers(wc->w_target_page, start+copied,
1918 				       start+len);
1919 	}
1920 	flush_dcache_page(wc->w_target_page);
1921 
1922 	for(i = 0; i < wc->w_num_pages; i++) {
1923 		tmppage = wc->w_pages[i];
1924 
1925 		if (tmppage == wc->w_target_page) {
1926 			from = wc->w_target_from;
1927 			to = wc->w_target_to;
1928 
1929 			BUG_ON(from > PAGE_CACHE_SIZE ||
1930 			       to > PAGE_CACHE_SIZE ||
1931 			       to < from);
1932 		} else {
1933 			/*
1934 			 * Pages adjacent to the target (if any) imply
1935 			 * a hole-filling write in which case we want
1936 			 * to flush their entire range.
1937 			 */
1938 			from = 0;
1939 			to = PAGE_CACHE_SIZE;
1940 		}
1941 
1942 		if (page_has_buffers(tmppage)) {
1943 			if (ocfs2_should_order_data(inode))
1944 				ocfs2_jbd2_file_inode(wc->w_handle, inode);
1945 			block_commit_write(tmppage, from, to);
1946 		}
1947 	}
1948 
1949 out_write_size:
1950 	pos += copied;
1951 	if (pos > inode->i_size) {
1952 		i_size_write(inode, pos);
1953 		mark_inode_dirty(inode);
1954 	}
1955 	inode->i_blocks = ocfs2_inode_sector_count(inode);
1956 	di->i_size = cpu_to_le64((u64)i_size_read(inode));
1957 	inode->i_mtime = inode->i_ctime = CURRENT_TIME;
1958 	di->i_mtime = di->i_ctime = cpu_to_le64(inode->i_mtime.tv_sec);
1959 	di->i_mtime_nsec = di->i_ctime_nsec = cpu_to_le32(inode->i_mtime.tv_nsec);
1960 	ocfs2_journal_dirty(handle, wc->w_di_bh);
1961 
1962 	ocfs2_commit_trans(osb, handle);
1963 
1964 	ocfs2_run_deallocs(osb, &wc->w_dealloc);
1965 
1966 	ocfs2_free_write_ctxt(wc);
1967 
1968 	return copied;
1969 }
1970 
1971 static int ocfs2_write_end(struct file *file, struct address_space *mapping,
1972 			   loff_t pos, unsigned len, unsigned copied,
1973 			   struct page *page, void *fsdata)
1974 {
1975 	int ret;
1976 	struct inode *inode = mapping->host;
1977 
1978 	ret = ocfs2_write_end_nolock(mapping, pos, len, copied, page, fsdata);
1979 
1980 	up_write(&OCFS2_I(inode)->ip_alloc_sem);
1981 	ocfs2_inode_unlock(inode, 1);
1982 
1983 	return ret;
1984 }
1985 
1986 const struct address_space_operations ocfs2_aops = {
1987 	.readpage		= ocfs2_readpage,
1988 	.readpages		= ocfs2_readpages,
1989 	.writepage		= ocfs2_writepage,
1990 	.write_begin		= ocfs2_write_begin,
1991 	.write_end		= ocfs2_write_end,
1992 	.bmap			= ocfs2_bmap,
1993 	.sync_page		= block_sync_page,
1994 	.direct_IO		= ocfs2_direct_IO,
1995 	.invalidatepage		= ocfs2_invalidatepage,
1996 	.releasepage		= ocfs2_releasepage,
1997 	.migratepage		= buffer_migrate_page,
1998 	.is_partially_uptodate	= block_is_partially_uptodate,
1999 	.error_remove_page	= generic_error_remove_page,
2000 };
2001