xref: /linux/fs/ocfs2/file.c (revision 0dd9ac63ce26ec87b080ca9c3e6efed33c23ace6)
1 /* -*- mode: c; c-basic-offset: 8; -*-
2  * vim: noexpandtab sw=8 ts=8 sts=0:
3  *
4  * file.c
5  *
6  * File open, close, extend, truncate
7  *
8  * Copyright (C) 2002, 2004 Oracle.  All rights reserved.
9  *
10  * This program is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU General Public
12  * License as published by the Free Software Foundation; either
13  * version 2 of the License, or (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
18  * General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public
21  * License along with this program; if not, write to the
22  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
23  * Boston, MA 021110-1307, USA.
24  */
25 
26 #include <linux/capability.h>
27 #include <linux/fs.h>
28 #include <linux/types.h>
29 #include <linux/slab.h>
30 #include <linux/highmem.h>
31 #include <linux/pagemap.h>
32 #include <linux/uio.h>
33 #include <linux/sched.h>
34 #include <linux/splice.h>
35 #include <linux/mount.h>
36 #include <linux/writeback.h>
37 #include <linux/falloc.h>
38 #include <linux/quotaops.h>
39 
40 #define MLOG_MASK_PREFIX ML_INODE
41 #include <cluster/masklog.h>
42 
43 #include "ocfs2.h"
44 
45 #include "alloc.h"
46 #include "aops.h"
47 #include "dir.h"
48 #include "dlmglue.h"
49 #include "extent_map.h"
50 #include "file.h"
51 #include "sysfile.h"
52 #include "inode.h"
53 #include "ioctl.h"
54 #include "journal.h"
55 #include "locks.h"
56 #include "mmap.h"
57 #include "suballoc.h"
58 #include "super.h"
59 #include "xattr.h"
60 #include "acl.h"
61 #include "quota.h"
62 #include "refcounttree.h"
63 
64 #include "buffer_head_io.h"
65 
66 static int ocfs2_sync_inode(struct inode *inode)
67 {
68 	filemap_fdatawrite(inode->i_mapping);
69 	return sync_mapping_buffers(inode->i_mapping);
70 }
71 
72 static int ocfs2_init_file_private(struct inode *inode, struct file *file)
73 {
74 	struct ocfs2_file_private *fp;
75 
76 	fp = kzalloc(sizeof(struct ocfs2_file_private), GFP_KERNEL);
77 	if (!fp)
78 		return -ENOMEM;
79 
80 	fp->fp_file = file;
81 	mutex_init(&fp->fp_mutex);
82 	ocfs2_file_lock_res_init(&fp->fp_flock, fp);
83 	file->private_data = fp;
84 
85 	return 0;
86 }
87 
88 static void ocfs2_free_file_private(struct inode *inode, struct file *file)
89 {
90 	struct ocfs2_file_private *fp = file->private_data;
91 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
92 
93 	if (fp) {
94 		ocfs2_simple_drop_lockres(osb, &fp->fp_flock);
95 		ocfs2_lock_res_free(&fp->fp_flock);
96 		kfree(fp);
97 		file->private_data = NULL;
98 	}
99 }
100 
101 static int ocfs2_file_open(struct inode *inode, struct file *file)
102 {
103 	int status;
104 	int mode = file->f_flags;
105 	struct ocfs2_inode_info *oi = OCFS2_I(inode);
106 
107 	mlog_entry("(0x%p, 0x%p, '%.*s')\n", inode, file,
108 		   file->f_path.dentry->d_name.len, file->f_path.dentry->d_name.name);
109 
110 	if (file->f_mode & FMODE_WRITE)
111 		dquot_initialize(inode);
112 
113 	spin_lock(&oi->ip_lock);
114 
115 	/* Check that the inode hasn't been wiped from disk by another
116 	 * node. If it hasn't then we're safe as long as we hold the
117 	 * spin lock until our increment of open count. */
118 	if (OCFS2_I(inode)->ip_flags & OCFS2_INODE_DELETED) {
119 		spin_unlock(&oi->ip_lock);
120 
121 		status = -ENOENT;
122 		goto leave;
123 	}
124 
125 	if (mode & O_DIRECT)
126 		oi->ip_flags |= OCFS2_INODE_OPEN_DIRECT;
127 
128 	oi->ip_open_count++;
129 	spin_unlock(&oi->ip_lock);
130 
131 	status = ocfs2_init_file_private(inode, file);
132 	if (status) {
133 		/*
134 		 * We want to set open count back if we're failing the
135 		 * open.
136 		 */
137 		spin_lock(&oi->ip_lock);
138 		oi->ip_open_count--;
139 		spin_unlock(&oi->ip_lock);
140 	}
141 
142 leave:
143 	mlog_exit(status);
144 	return status;
145 }
146 
147 static int ocfs2_file_release(struct inode *inode, struct file *file)
148 {
149 	struct ocfs2_inode_info *oi = OCFS2_I(inode);
150 
151 	mlog_entry("(0x%p, 0x%p, '%.*s')\n", inode, file,
152 		       file->f_path.dentry->d_name.len,
153 		       file->f_path.dentry->d_name.name);
154 
155 	spin_lock(&oi->ip_lock);
156 	if (!--oi->ip_open_count)
157 		oi->ip_flags &= ~OCFS2_INODE_OPEN_DIRECT;
158 	spin_unlock(&oi->ip_lock);
159 
160 	ocfs2_free_file_private(inode, file);
161 
162 	mlog_exit(0);
163 
164 	return 0;
165 }
166 
167 static int ocfs2_dir_open(struct inode *inode, struct file *file)
168 {
169 	return ocfs2_init_file_private(inode, file);
170 }
171 
172 static int ocfs2_dir_release(struct inode *inode, struct file *file)
173 {
174 	ocfs2_free_file_private(inode, file);
175 	return 0;
176 }
177 
178 static int ocfs2_sync_file(struct file *file, int datasync)
179 {
180 	int err = 0;
181 	journal_t *journal;
182 	struct dentry *dentry = file->f_path.dentry;
183 	struct inode *inode = file->f_mapping->host;
184 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
185 
186 	mlog_entry("(0x%p, 0x%p, %d, '%.*s')\n", file, dentry, datasync,
187 		   dentry->d_name.len, dentry->d_name.name);
188 
189 	err = ocfs2_sync_inode(dentry->d_inode);
190 	if (err)
191 		goto bail;
192 
193 	if (datasync && !(inode->i_state & I_DIRTY_DATASYNC))
194 		goto bail;
195 
196 	journal = osb->journal->j_journal;
197 	err = jbd2_journal_force_commit(journal);
198 
199 bail:
200 	mlog_exit(err);
201 
202 	return (err < 0) ? -EIO : 0;
203 }
204 
205 int ocfs2_should_update_atime(struct inode *inode,
206 			      struct vfsmount *vfsmnt)
207 {
208 	struct timespec now;
209 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
210 
211 	if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
212 		return 0;
213 
214 	if ((inode->i_flags & S_NOATIME) ||
215 	    ((inode->i_sb->s_flags & MS_NODIRATIME) && S_ISDIR(inode->i_mode)))
216 		return 0;
217 
218 	/*
219 	 * We can be called with no vfsmnt structure - NFSD will
220 	 * sometimes do this.
221 	 *
222 	 * Note that our action here is different than touch_atime() -
223 	 * if we can't tell whether this is a noatime mount, then we
224 	 * don't know whether to trust the value of s_atime_quantum.
225 	 */
226 	if (vfsmnt == NULL)
227 		return 0;
228 
229 	if ((vfsmnt->mnt_flags & MNT_NOATIME) ||
230 	    ((vfsmnt->mnt_flags & MNT_NODIRATIME) && S_ISDIR(inode->i_mode)))
231 		return 0;
232 
233 	if (vfsmnt->mnt_flags & MNT_RELATIME) {
234 		if ((timespec_compare(&inode->i_atime, &inode->i_mtime) <= 0) ||
235 		    (timespec_compare(&inode->i_atime, &inode->i_ctime) <= 0))
236 			return 1;
237 
238 		return 0;
239 	}
240 
241 	now = CURRENT_TIME;
242 	if ((now.tv_sec - inode->i_atime.tv_sec <= osb->s_atime_quantum))
243 		return 0;
244 	else
245 		return 1;
246 }
247 
248 int ocfs2_update_inode_atime(struct inode *inode,
249 			     struct buffer_head *bh)
250 {
251 	int ret;
252 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
253 	handle_t *handle;
254 	struct ocfs2_dinode *di = (struct ocfs2_dinode *) bh->b_data;
255 
256 	mlog_entry_void();
257 
258 	handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
259 	if (IS_ERR(handle)) {
260 		ret = PTR_ERR(handle);
261 		mlog_errno(ret);
262 		goto out;
263 	}
264 
265 	ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), bh,
266 				      OCFS2_JOURNAL_ACCESS_WRITE);
267 	if (ret) {
268 		mlog_errno(ret);
269 		goto out_commit;
270 	}
271 
272 	/*
273 	 * Don't use ocfs2_mark_inode_dirty() here as we don't always
274 	 * have i_mutex to guard against concurrent changes to other
275 	 * inode fields.
276 	 */
277 	inode->i_atime = CURRENT_TIME;
278 	di->i_atime = cpu_to_le64(inode->i_atime.tv_sec);
279 	di->i_atime_nsec = cpu_to_le32(inode->i_atime.tv_nsec);
280 	ocfs2_journal_dirty(handle, bh);
281 
282 out_commit:
283 	ocfs2_commit_trans(OCFS2_SB(inode->i_sb), handle);
284 out:
285 	mlog_exit(ret);
286 	return ret;
287 }
288 
289 static int ocfs2_set_inode_size(handle_t *handle,
290 				struct inode *inode,
291 				struct buffer_head *fe_bh,
292 				u64 new_i_size)
293 {
294 	int status;
295 
296 	mlog_entry_void();
297 	i_size_write(inode, new_i_size);
298 	inode->i_blocks = ocfs2_inode_sector_count(inode);
299 	inode->i_ctime = inode->i_mtime = CURRENT_TIME;
300 
301 	status = ocfs2_mark_inode_dirty(handle, inode, fe_bh);
302 	if (status < 0) {
303 		mlog_errno(status);
304 		goto bail;
305 	}
306 
307 bail:
308 	mlog_exit(status);
309 	return status;
310 }
311 
312 int ocfs2_simple_size_update(struct inode *inode,
313 			     struct buffer_head *di_bh,
314 			     u64 new_i_size)
315 {
316 	int ret;
317 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
318 	handle_t *handle = NULL;
319 
320 	handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
321 	if (IS_ERR(handle)) {
322 		ret = PTR_ERR(handle);
323 		mlog_errno(ret);
324 		goto out;
325 	}
326 
327 	ret = ocfs2_set_inode_size(handle, inode, di_bh,
328 				   new_i_size);
329 	if (ret < 0)
330 		mlog_errno(ret);
331 
332 	ocfs2_commit_trans(osb, handle);
333 out:
334 	return ret;
335 }
336 
337 static int ocfs2_cow_file_pos(struct inode *inode,
338 			      struct buffer_head *fe_bh,
339 			      u64 offset)
340 {
341 	int status;
342 	u32 phys, cpos = offset >> OCFS2_SB(inode->i_sb)->s_clustersize_bits;
343 	unsigned int num_clusters = 0;
344 	unsigned int ext_flags = 0;
345 
346 	/*
347 	 * If the new offset is aligned to the range of the cluster, there is
348 	 * no space for ocfs2_zero_range_for_truncate to fill, so no need to
349 	 * CoW either.
350 	 */
351 	if ((offset & (OCFS2_SB(inode->i_sb)->s_clustersize - 1)) == 0)
352 		return 0;
353 
354 	status = ocfs2_get_clusters(inode, cpos, &phys,
355 				    &num_clusters, &ext_flags);
356 	if (status) {
357 		mlog_errno(status);
358 		goto out;
359 	}
360 
361 	if (!(ext_flags & OCFS2_EXT_REFCOUNTED))
362 		goto out;
363 
364 	return ocfs2_refcount_cow(inode, fe_bh, cpos, 1, cpos+1);
365 
366 out:
367 	return status;
368 }
369 
370 static int ocfs2_orphan_for_truncate(struct ocfs2_super *osb,
371 				     struct inode *inode,
372 				     struct buffer_head *fe_bh,
373 				     u64 new_i_size)
374 {
375 	int status;
376 	handle_t *handle;
377 	struct ocfs2_dinode *di;
378 	u64 cluster_bytes;
379 
380 	mlog_entry_void();
381 
382 	/*
383 	 * We need to CoW the cluster contains the offset if it is reflinked
384 	 * since we will call ocfs2_zero_range_for_truncate later which will
385 	 * write "0" from offset to the end of the cluster.
386 	 */
387 	status = ocfs2_cow_file_pos(inode, fe_bh, new_i_size);
388 	if (status) {
389 		mlog_errno(status);
390 		return status;
391 	}
392 
393 	/* TODO: This needs to actually orphan the inode in this
394 	 * transaction. */
395 
396 	handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
397 	if (IS_ERR(handle)) {
398 		status = PTR_ERR(handle);
399 		mlog_errno(status);
400 		goto out;
401 	}
402 
403 	status = ocfs2_journal_access_di(handle, INODE_CACHE(inode), fe_bh,
404 					 OCFS2_JOURNAL_ACCESS_WRITE);
405 	if (status < 0) {
406 		mlog_errno(status);
407 		goto out_commit;
408 	}
409 
410 	/*
411 	 * Do this before setting i_size.
412 	 */
413 	cluster_bytes = ocfs2_align_bytes_to_clusters(inode->i_sb, new_i_size);
414 	status = ocfs2_zero_range_for_truncate(inode, handle, new_i_size,
415 					       cluster_bytes);
416 	if (status) {
417 		mlog_errno(status);
418 		goto out_commit;
419 	}
420 
421 	i_size_write(inode, new_i_size);
422 	inode->i_ctime = inode->i_mtime = CURRENT_TIME;
423 
424 	di = (struct ocfs2_dinode *) fe_bh->b_data;
425 	di->i_size = cpu_to_le64(new_i_size);
426 	di->i_ctime = di->i_mtime = cpu_to_le64(inode->i_ctime.tv_sec);
427 	di->i_ctime_nsec = di->i_mtime_nsec = cpu_to_le32(inode->i_ctime.tv_nsec);
428 
429 	ocfs2_journal_dirty(handle, fe_bh);
430 
431 out_commit:
432 	ocfs2_commit_trans(osb, handle);
433 out:
434 
435 	mlog_exit(status);
436 	return status;
437 }
438 
439 static int ocfs2_truncate_file(struct inode *inode,
440 			       struct buffer_head *di_bh,
441 			       u64 new_i_size)
442 {
443 	int status = 0;
444 	struct ocfs2_dinode *fe = NULL;
445 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
446 
447 	mlog_entry("(inode = %llu, new_i_size = %llu\n",
448 		   (unsigned long long)OCFS2_I(inode)->ip_blkno,
449 		   (unsigned long long)new_i_size);
450 
451 	/* We trust di_bh because it comes from ocfs2_inode_lock(), which
452 	 * already validated it */
453 	fe = (struct ocfs2_dinode *) di_bh->b_data;
454 
455 	mlog_bug_on_msg(le64_to_cpu(fe->i_size) != i_size_read(inode),
456 			"Inode %llu, inode i_size = %lld != di "
457 			"i_size = %llu, i_flags = 0x%x\n",
458 			(unsigned long long)OCFS2_I(inode)->ip_blkno,
459 			i_size_read(inode),
460 			(unsigned long long)le64_to_cpu(fe->i_size),
461 			le32_to_cpu(fe->i_flags));
462 
463 	if (new_i_size > le64_to_cpu(fe->i_size)) {
464 		mlog(0, "asked to truncate file with size (%llu) to size (%llu)!\n",
465 		     (unsigned long long)le64_to_cpu(fe->i_size),
466 		     (unsigned long long)new_i_size);
467 		status = -EINVAL;
468 		mlog_errno(status);
469 		goto bail;
470 	}
471 
472 	mlog(0, "inode %llu, i_size = %llu, new_i_size = %llu\n",
473 	     (unsigned long long)le64_to_cpu(fe->i_blkno),
474 	     (unsigned long long)le64_to_cpu(fe->i_size),
475 	     (unsigned long long)new_i_size);
476 
477 	/* lets handle the simple truncate cases before doing any more
478 	 * cluster locking. */
479 	if (new_i_size == le64_to_cpu(fe->i_size))
480 		goto bail;
481 
482 	down_write(&OCFS2_I(inode)->ip_alloc_sem);
483 
484 	ocfs2_resv_discard(&osb->osb_la_resmap,
485 			   &OCFS2_I(inode)->ip_la_data_resv);
486 
487 	/*
488 	 * The inode lock forced other nodes to sync and drop their
489 	 * pages, which (correctly) happens even if we have a truncate
490 	 * without allocation change - ocfs2 cluster sizes can be much
491 	 * greater than page size, so we have to truncate them
492 	 * anyway.
493 	 */
494 	unmap_mapping_range(inode->i_mapping, new_i_size + PAGE_SIZE - 1, 0, 1);
495 	truncate_inode_pages(inode->i_mapping, new_i_size);
496 
497 	if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
498 		status = ocfs2_truncate_inline(inode, di_bh, new_i_size,
499 					       i_size_read(inode), 1);
500 		if (status)
501 			mlog_errno(status);
502 
503 		goto bail_unlock_sem;
504 	}
505 
506 	/* alright, we're going to need to do a full blown alloc size
507 	 * change. Orphan the inode so that recovery can complete the
508 	 * truncate if necessary. This does the task of marking
509 	 * i_size. */
510 	status = ocfs2_orphan_for_truncate(osb, inode, di_bh, new_i_size);
511 	if (status < 0) {
512 		mlog_errno(status);
513 		goto bail_unlock_sem;
514 	}
515 
516 	status = ocfs2_commit_truncate(osb, inode, di_bh);
517 	if (status < 0) {
518 		mlog_errno(status);
519 		goto bail_unlock_sem;
520 	}
521 
522 	/* TODO: orphan dir cleanup here. */
523 bail_unlock_sem:
524 	up_write(&OCFS2_I(inode)->ip_alloc_sem);
525 
526 bail:
527 	if (!status && OCFS2_I(inode)->ip_clusters == 0)
528 		status = ocfs2_try_remove_refcount_tree(inode, di_bh);
529 
530 	mlog_exit(status);
531 	return status;
532 }
533 
534 /*
535  * extend file allocation only here.
536  * we'll update all the disk stuff, and oip->alloc_size
537  *
538  * expect stuff to be locked, a transaction started and enough data /
539  * metadata reservations in the contexts.
540  *
541  * Will return -EAGAIN, and a reason if a restart is needed.
542  * If passed in, *reason will always be set, even in error.
543  */
544 int ocfs2_add_inode_data(struct ocfs2_super *osb,
545 			 struct inode *inode,
546 			 u32 *logical_offset,
547 			 u32 clusters_to_add,
548 			 int mark_unwritten,
549 			 struct buffer_head *fe_bh,
550 			 handle_t *handle,
551 			 struct ocfs2_alloc_context *data_ac,
552 			 struct ocfs2_alloc_context *meta_ac,
553 			 enum ocfs2_alloc_restarted *reason_ret)
554 {
555 	int ret;
556 	struct ocfs2_extent_tree et;
557 
558 	ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode), fe_bh);
559 	ret = ocfs2_add_clusters_in_btree(handle, &et, logical_offset,
560 					  clusters_to_add, mark_unwritten,
561 					  data_ac, meta_ac, reason_ret);
562 
563 	return ret;
564 }
565 
566 static int __ocfs2_extend_allocation(struct inode *inode, u32 logical_start,
567 				     u32 clusters_to_add, int mark_unwritten)
568 {
569 	int status = 0;
570 	int restart_func = 0;
571 	int credits;
572 	u32 prev_clusters;
573 	struct buffer_head *bh = NULL;
574 	struct ocfs2_dinode *fe = NULL;
575 	handle_t *handle = NULL;
576 	struct ocfs2_alloc_context *data_ac = NULL;
577 	struct ocfs2_alloc_context *meta_ac = NULL;
578 	enum ocfs2_alloc_restarted why;
579 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
580 	struct ocfs2_extent_tree et;
581 	int did_quota = 0;
582 
583 	mlog_entry("(clusters_to_add = %u)\n", clusters_to_add);
584 
585 	/*
586 	 * This function only exists for file systems which don't
587 	 * support holes.
588 	 */
589 	BUG_ON(mark_unwritten && !ocfs2_sparse_alloc(osb));
590 
591 	status = ocfs2_read_inode_block(inode, &bh);
592 	if (status < 0) {
593 		mlog_errno(status);
594 		goto leave;
595 	}
596 	fe = (struct ocfs2_dinode *) bh->b_data;
597 
598 restart_all:
599 	BUG_ON(le32_to_cpu(fe->i_clusters) != OCFS2_I(inode)->ip_clusters);
600 
601 	mlog(0, "extend inode %llu, i_size = %lld, di->i_clusters = %u, "
602 	     "clusters_to_add = %u\n",
603 	     (unsigned long long)OCFS2_I(inode)->ip_blkno,
604 	     (long long)i_size_read(inode), le32_to_cpu(fe->i_clusters),
605 	     clusters_to_add);
606 	ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode), bh);
607 	status = ocfs2_lock_allocators(inode, &et, clusters_to_add, 0,
608 				       &data_ac, &meta_ac);
609 	if (status) {
610 		mlog_errno(status);
611 		goto leave;
612 	}
613 
614 	credits = ocfs2_calc_extend_credits(osb->sb, &fe->id2.i_list,
615 					    clusters_to_add);
616 	handle = ocfs2_start_trans(osb, credits);
617 	if (IS_ERR(handle)) {
618 		status = PTR_ERR(handle);
619 		handle = NULL;
620 		mlog_errno(status);
621 		goto leave;
622 	}
623 
624 restarted_transaction:
625 	status = dquot_alloc_space_nodirty(inode,
626 			ocfs2_clusters_to_bytes(osb->sb, clusters_to_add));
627 	if (status)
628 		goto leave;
629 	did_quota = 1;
630 
631 	/* reserve a write to the file entry early on - that we if we
632 	 * run out of credits in the allocation path, we can still
633 	 * update i_size. */
634 	status = ocfs2_journal_access_di(handle, INODE_CACHE(inode), bh,
635 					 OCFS2_JOURNAL_ACCESS_WRITE);
636 	if (status < 0) {
637 		mlog_errno(status);
638 		goto leave;
639 	}
640 
641 	prev_clusters = OCFS2_I(inode)->ip_clusters;
642 
643 	status = ocfs2_add_inode_data(osb,
644 				      inode,
645 				      &logical_start,
646 				      clusters_to_add,
647 				      mark_unwritten,
648 				      bh,
649 				      handle,
650 				      data_ac,
651 				      meta_ac,
652 				      &why);
653 	if ((status < 0) && (status != -EAGAIN)) {
654 		if (status != -ENOSPC)
655 			mlog_errno(status);
656 		goto leave;
657 	}
658 
659 	ocfs2_journal_dirty(handle, bh);
660 
661 	spin_lock(&OCFS2_I(inode)->ip_lock);
662 	clusters_to_add -= (OCFS2_I(inode)->ip_clusters - prev_clusters);
663 	spin_unlock(&OCFS2_I(inode)->ip_lock);
664 	/* Release unused quota reservation */
665 	dquot_free_space(inode,
666 			ocfs2_clusters_to_bytes(osb->sb, clusters_to_add));
667 	did_quota = 0;
668 
669 	if (why != RESTART_NONE && clusters_to_add) {
670 		if (why == RESTART_META) {
671 			mlog(0, "restarting function.\n");
672 			restart_func = 1;
673 			status = 0;
674 		} else {
675 			BUG_ON(why != RESTART_TRANS);
676 
677 			mlog(0, "restarting transaction.\n");
678 			/* TODO: This can be more intelligent. */
679 			credits = ocfs2_calc_extend_credits(osb->sb,
680 							    &fe->id2.i_list,
681 							    clusters_to_add);
682 			status = ocfs2_extend_trans(handle, credits);
683 			if (status < 0) {
684 				/* handle still has to be committed at
685 				 * this point. */
686 				status = -ENOMEM;
687 				mlog_errno(status);
688 				goto leave;
689 			}
690 			goto restarted_transaction;
691 		}
692 	}
693 
694 	mlog(0, "fe: i_clusters = %u, i_size=%llu\n",
695 	     le32_to_cpu(fe->i_clusters),
696 	     (unsigned long long)le64_to_cpu(fe->i_size));
697 	mlog(0, "inode: ip_clusters=%u, i_size=%lld\n",
698 	     OCFS2_I(inode)->ip_clusters, (long long)i_size_read(inode));
699 
700 leave:
701 	if (status < 0 && did_quota)
702 		dquot_free_space(inode,
703 			ocfs2_clusters_to_bytes(osb->sb, clusters_to_add));
704 	if (handle) {
705 		ocfs2_commit_trans(osb, handle);
706 		handle = NULL;
707 	}
708 	if (data_ac) {
709 		ocfs2_free_alloc_context(data_ac);
710 		data_ac = NULL;
711 	}
712 	if (meta_ac) {
713 		ocfs2_free_alloc_context(meta_ac);
714 		meta_ac = NULL;
715 	}
716 	if ((!status) && restart_func) {
717 		restart_func = 0;
718 		goto restart_all;
719 	}
720 	brelse(bh);
721 	bh = NULL;
722 
723 	mlog_exit(status);
724 	return status;
725 }
726 
727 /* Some parts of this taken from generic_cont_expand, which turned out
728  * to be too fragile to do exactly what we need without us having to
729  * worry about recursive locking in ->write_begin() and ->write_end(). */
730 static int ocfs2_write_zero_page(struct inode *inode,
731 				 u64 size)
732 {
733 	struct address_space *mapping = inode->i_mapping;
734 	struct page *page;
735 	unsigned long index;
736 	unsigned int offset;
737 	handle_t *handle = NULL;
738 	int ret;
739 
740 	offset = (size & (PAGE_CACHE_SIZE-1)); /* Within page */
741 	/* ugh.  in prepare/commit_write, if from==to==start of block, we
742 	** skip the prepare.  make sure we never send an offset for the start
743 	** of a block
744 	*/
745 	if ((offset & (inode->i_sb->s_blocksize - 1)) == 0) {
746 		offset++;
747 	}
748 	index = size >> PAGE_CACHE_SHIFT;
749 
750 	page = grab_cache_page(mapping, index);
751 	if (!page) {
752 		ret = -ENOMEM;
753 		mlog_errno(ret);
754 		goto out;
755 	}
756 
757 	ret = ocfs2_prepare_write_nolock(inode, page, offset, offset);
758 	if (ret < 0) {
759 		mlog_errno(ret);
760 		goto out_unlock;
761 	}
762 
763 	if (ocfs2_should_order_data(inode)) {
764 		handle = ocfs2_start_walk_page_trans(inode, page, offset,
765 						     offset);
766 		if (IS_ERR(handle)) {
767 			ret = PTR_ERR(handle);
768 			handle = NULL;
769 			goto out_unlock;
770 		}
771 	}
772 
773 	/* must not update i_size! */
774 	ret = block_commit_write(page, offset, offset);
775 	if (ret < 0)
776 		mlog_errno(ret);
777 	else
778 		ret = 0;
779 
780 	if (handle)
781 		ocfs2_commit_trans(OCFS2_SB(inode->i_sb), handle);
782 out_unlock:
783 	unlock_page(page);
784 	page_cache_release(page);
785 out:
786 	return ret;
787 }
788 
789 static int ocfs2_zero_extend(struct inode *inode,
790 			     u64 zero_to_size)
791 {
792 	int ret = 0;
793 	u64 start_off;
794 	struct super_block *sb = inode->i_sb;
795 
796 	start_off = ocfs2_align_bytes_to_blocks(sb, i_size_read(inode));
797 	while (start_off < zero_to_size) {
798 		ret = ocfs2_write_zero_page(inode, start_off);
799 		if (ret < 0) {
800 			mlog_errno(ret);
801 			goto out;
802 		}
803 
804 		start_off += sb->s_blocksize;
805 
806 		/*
807 		 * Very large extends have the potential to lock up
808 		 * the cpu for extended periods of time.
809 		 */
810 		cond_resched();
811 	}
812 
813 out:
814 	return ret;
815 }
816 
817 int ocfs2_extend_no_holes(struct inode *inode, u64 new_i_size, u64 zero_to)
818 {
819 	int ret;
820 	u32 clusters_to_add;
821 	struct ocfs2_inode_info *oi = OCFS2_I(inode);
822 
823 	clusters_to_add = ocfs2_clusters_for_bytes(inode->i_sb, new_i_size);
824 	if (clusters_to_add < oi->ip_clusters)
825 		clusters_to_add = 0;
826 	else
827 		clusters_to_add -= oi->ip_clusters;
828 
829 	if (clusters_to_add) {
830 		ret = __ocfs2_extend_allocation(inode, oi->ip_clusters,
831 						clusters_to_add, 0);
832 		if (ret) {
833 			mlog_errno(ret);
834 			goto out;
835 		}
836 	}
837 
838 	/*
839 	 * Call this even if we don't add any clusters to the tree. We
840 	 * still need to zero the area between the old i_size and the
841 	 * new i_size.
842 	 */
843 	ret = ocfs2_zero_extend(inode, zero_to);
844 	if (ret < 0)
845 		mlog_errno(ret);
846 
847 out:
848 	return ret;
849 }
850 
851 static int ocfs2_extend_file(struct inode *inode,
852 			     struct buffer_head *di_bh,
853 			     u64 new_i_size)
854 {
855 	int ret = 0;
856 	struct ocfs2_inode_info *oi = OCFS2_I(inode);
857 
858 	BUG_ON(!di_bh);
859 
860 	/* setattr sometimes calls us like this. */
861 	if (new_i_size == 0)
862 		goto out;
863 
864 	if (i_size_read(inode) == new_i_size)
865   		goto out;
866 	BUG_ON(new_i_size < i_size_read(inode));
867 
868 	/*
869 	 * Fall through for converting inline data, even if the fs
870 	 * supports sparse files.
871 	 *
872 	 * The check for inline data here is legal - nobody can add
873 	 * the feature since we have i_mutex. We must check it again
874 	 * after acquiring ip_alloc_sem though, as paths like mmap
875 	 * might have raced us to converting the inode to extents.
876 	 */
877 	if (!(oi->ip_dyn_features & OCFS2_INLINE_DATA_FL)
878 	    && ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb)))
879 		goto out_update_size;
880 
881 	/*
882 	 * The alloc sem blocks people in read/write from reading our
883 	 * allocation until we're done changing it. We depend on
884 	 * i_mutex to block other extend/truncate calls while we're
885 	 * here.
886 	 */
887 	down_write(&oi->ip_alloc_sem);
888 
889 	if (oi->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
890 		/*
891 		 * We can optimize small extends by keeping the inodes
892 		 * inline data.
893 		 */
894 		if (ocfs2_size_fits_inline_data(di_bh, new_i_size)) {
895 			up_write(&oi->ip_alloc_sem);
896 			goto out_update_size;
897 		}
898 
899 		ret = ocfs2_convert_inline_data_to_extents(inode, di_bh);
900 		if (ret) {
901 			up_write(&oi->ip_alloc_sem);
902 
903 			mlog_errno(ret);
904 			goto out;
905 		}
906 	}
907 
908 	if (!ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb)))
909 		ret = ocfs2_extend_no_holes(inode, new_i_size, new_i_size);
910 
911 	up_write(&oi->ip_alloc_sem);
912 
913 	if (ret < 0) {
914 		mlog_errno(ret);
915 		goto out;
916 	}
917 
918 out_update_size:
919 	ret = ocfs2_simple_size_update(inode, di_bh, new_i_size);
920 	if (ret < 0)
921 		mlog_errno(ret);
922 
923 out:
924 	return ret;
925 }
926 
927 int ocfs2_setattr(struct dentry *dentry, struct iattr *attr)
928 {
929 	int status = 0, size_change;
930 	struct inode *inode = dentry->d_inode;
931 	struct super_block *sb = inode->i_sb;
932 	struct ocfs2_super *osb = OCFS2_SB(sb);
933 	struct buffer_head *bh = NULL;
934 	handle_t *handle = NULL;
935 	struct dquot *transfer_to[MAXQUOTAS] = { };
936 	int qtype;
937 
938 	mlog_entry("(0x%p, '%.*s')\n", dentry,
939 	           dentry->d_name.len, dentry->d_name.name);
940 
941 	/* ensuring we don't even attempt to truncate a symlink */
942 	if (S_ISLNK(inode->i_mode))
943 		attr->ia_valid &= ~ATTR_SIZE;
944 
945 	if (attr->ia_valid & ATTR_MODE)
946 		mlog(0, "mode change: %d\n", attr->ia_mode);
947 	if (attr->ia_valid & ATTR_UID)
948 		mlog(0, "uid change: %d\n", attr->ia_uid);
949 	if (attr->ia_valid & ATTR_GID)
950 		mlog(0, "gid change: %d\n", attr->ia_gid);
951 	if (attr->ia_valid & ATTR_SIZE)
952 		mlog(0, "size change...\n");
953 	if (attr->ia_valid & (ATTR_ATIME | ATTR_MTIME | ATTR_CTIME))
954 		mlog(0, "time change...\n");
955 
956 #define OCFS2_VALID_ATTRS (ATTR_ATIME | ATTR_MTIME | ATTR_CTIME | ATTR_SIZE \
957 			   | ATTR_GID | ATTR_UID | ATTR_MODE)
958 	if (!(attr->ia_valid & OCFS2_VALID_ATTRS)) {
959 		mlog(0, "can't handle attrs: 0x%x\n", attr->ia_valid);
960 		return 0;
961 	}
962 
963 	status = inode_change_ok(inode, attr);
964 	if (status)
965 		return status;
966 
967 	if (is_quota_modification(inode, attr))
968 		dquot_initialize(inode);
969 	size_change = S_ISREG(inode->i_mode) && attr->ia_valid & ATTR_SIZE;
970 	if (size_change) {
971 		status = ocfs2_rw_lock(inode, 1);
972 		if (status < 0) {
973 			mlog_errno(status);
974 			goto bail;
975 		}
976 	}
977 
978 	status = ocfs2_inode_lock(inode, &bh, 1);
979 	if (status < 0) {
980 		if (status != -ENOENT)
981 			mlog_errno(status);
982 		goto bail_unlock_rw;
983 	}
984 
985 	if (size_change && attr->ia_size != i_size_read(inode)) {
986 		status = inode_newsize_ok(inode, attr->ia_size);
987 		if (status)
988 			goto bail_unlock;
989 
990 		if (i_size_read(inode) > attr->ia_size) {
991 			if (ocfs2_should_order_data(inode)) {
992 				status = ocfs2_begin_ordered_truncate(inode,
993 								      attr->ia_size);
994 				if (status)
995 					goto bail_unlock;
996 			}
997 			status = ocfs2_truncate_file(inode, bh, attr->ia_size);
998 		} else
999 			status = ocfs2_extend_file(inode, bh, attr->ia_size);
1000 		if (status < 0) {
1001 			if (status != -ENOSPC)
1002 				mlog_errno(status);
1003 			status = -ENOSPC;
1004 			goto bail_unlock;
1005 		}
1006 	}
1007 
1008 	if ((attr->ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid) ||
1009 	    (attr->ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid)) {
1010 		/*
1011 		 * Gather pointers to quota structures so that allocation /
1012 		 * freeing of quota structures happens here and not inside
1013 		 * dquot_transfer() where we have problems with lock ordering
1014 		 */
1015 		if (attr->ia_valid & ATTR_UID && attr->ia_uid != inode->i_uid
1016 		    && OCFS2_HAS_RO_COMPAT_FEATURE(sb,
1017 		    OCFS2_FEATURE_RO_COMPAT_USRQUOTA)) {
1018 			transfer_to[USRQUOTA] = dqget(sb, attr->ia_uid,
1019 						      USRQUOTA);
1020 			if (!transfer_to[USRQUOTA]) {
1021 				status = -ESRCH;
1022 				goto bail_unlock;
1023 			}
1024 		}
1025 		if (attr->ia_valid & ATTR_GID && attr->ia_gid != inode->i_gid
1026 		    && OCFS2_HAS_RO_COMPAT_FEATURE(sb,
1027 		    OCFS2_FEATURE_RO_COMPAT_GRPQUOTA)) {
1028 			transfer_to[GRPQUOTA] = dqget(sb, attr->ia_gid,
1029 						      GRPQUOTA);
1030 			if (!transfer_to[GRPQUOTA]) {
1031 				status = -ESRCH;
1032 				goto bail_unlock;
1033 			}
1034 		}
1035 		handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS +
1036 					   2 * ocfs2_quota_trans_credits(sb));
1037 		if (IS_ERR(handle)) {
1038 			status = PTR_ERR(handle);
1039 			mlog_errno(status);
1040 			goto bail_unlock;
1041 		}
1042 		status = __dquot_transfer(inode, transfer_to);
1043 		if (status < 0)
1044 			goto bail_commit;
1045 	} else {
1046 		handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
1047 		if (IS_ERR(handle)) {
1048 			status = PTR_ERR(handle);
1049 			mlog_errno(status);
1050 			goto bail_unlock;
1051 		}
1052 	}
1053 
1054 	/*
1055 	 * This will intentionally not wind up calling simple_setsize(),
1056 	 * since all the work for a size change has been done above.
1057 	 * Otherwise, we could get into problems with truncate as
1058 	 * ip_alloc_sem is used there to protect against i_size
1059 	 * changes.
1060 	 */
1061 	status = inode_setattr(inode, attr);
1062 	if (status < 0) {
1063 		mlog_errno(status);
1064 		goto bail_commit;
1065 	}
1066 
1067 	status = ocfs2_mark_inode_dirty(handle, inode, bh);
1068 	if (status < 0)
1069 		mlog_errno(status);
1070 
1071 bail_commit:
1072 	ocfs2_commit_trans(osb, handle);
1073 bail_unlock:
1074 	ocfs2_inode_unlock(inode, 1);
1075 bail_unlock_rw:
1076 	if (size_change)
1077 		ocfs2_rw_unlock(inode, 1);
1078 bail:
1079 	brelse(bh);
1080 
1081 	/* Release quota pointers in case we acquired them */
1082 	for (qtype = 0; qtype < MAXQUOTAS; qtype++)
1083 		dqput(transfer_to[qtype]);
1084 
1085 	if (!status && attr->ia_valid & ATTR_MODE) {
1086 		status = ocfs2_acl_chmod(inode);
1087 		if (status < 0)
1088 			mlog_errno(status);
1089 	}
1090 
1091 	mlog_exit(status);
1092 	return status;
1093 }
1094 
1095 int ocfs2_getattr(struct vfsmount *mnt,
1096 		  struct dentry *dentry,
1097 		  struct kstat *stat)
1098 {
1099 	struct inode *inode = dentry->d_inode;
1100 	struct super_block *sb = dentry->d_inode->i_sb;
1101 	struct ocfs2_super *osb = sb->s_fs_info;
1102 	int err;
1103 
1104 	mlog_entry_void();
1105 
1106 	err = ocfs2_inode_revalidate(dentry);
1107 	if (err) {
1108 		if (err != -ENOENT)
1109 			mlog_errno(err);
1110 		goto bail;
1111 	}
1112 
1113 	generic_fillattr(inode, stat);
1114 
1115 	/* We set the blksize from the cluster size for performance */
1116 	stat->blksize = osb->s_clustersize;
1117 
1118 bail:
1119 	mlog_exit(err);
1120 
1121 	return err;
1122 }
1123 
1124 int ocfs2_permission(struct inode *inode, int mask)
1125 {
1126 	int ret;
1127 
1128 	mlog_entry_void();
1129 
1130 	ret = ocfs2_inode_lock(inode, NULL, 0);
1131 	if (ret) {
1132 		if (ret != -ENOENT)
1133 			mlog_errno(ret);
1134 		goto out;
1135 	}
1136 
1137 	ret = generic_permission(inode, mask, ocfs2_check_acl);
1138 
1139 	ocfs2_inode_unlock(inode, 0);
1140 out:
1141 	mlog_exit(ret);
1142 	return ret;
1143 }
1144 
1145 static int __ocfs2_write_remove_suid(struct inode *inode,
1146 				     struct buffer_head *bh)
1147 {
1148 	int ret;
1149 	handle_t *handle;
1150 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1151 	struct ocfs2_dinode *di;
1152 
1153 	mlog_entry("(Inode %llu, mode 0%o)\n",
1154 		   (unsigned long long)OCFS2_I(inode)->ip_blkno, inode->i_mode);
1155 
1156 	handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
1157 	if (IS_ERR(handle)) {
1158 		ret = PTR_ERR(handle);
1159 		mlog_errno(ret);
1160 		goto out;
1161 	}
1162 
1163 	ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), bh,
1164 				      OCFS2_JOURNAL_ACCESS_WRITE);
1165 	if (ret < 0) {
1166 		mlog_errno(ret);
1167 		goto out_trans;
1168 	}
1169 
1170 	inode->i_mode &= ~S_ISUID;
1171 	if ((inode->i_mode & S_ISGID) && (inode->i_mode & S_IXGRP))
1172 		inode->i_mode &= ~S_ISGID;
1173 
1174 	di = (struct ocfs2_dinode *) bh->b_data;
1175 	di->i_mode = cpu_to_le16(inode->i_mode);
1176 
1177 	ocfs2_journal_dirty(handle, bh);
1178 
1179 out_trans:
1180 	ocfs2_commit_trans(osb, handle);
1181 out:
1182 	mlog_exit(ret);
1183 	return ret;
1184 }
1185 
1186 /*
1187  * Will look for holes and unwritten extents in the range starting at
1188  * pos for count bytes (inclusive).
1189  */
1190 static int ocfs2_check_range_for_holes(struct inode *inode, loff_t pos,
1191 				       size_t count)
1192 {
1193 	int ret = 0;
1194 	unsigned int extent_flags;
1195 	u32 cpos, clusters, extent_len, phys_cpos;
1196 	struct super_block *sb = inode->i_sb;
1197 
1198 	cpos = pos >> OCFS2_SB(sb)->s_clustersize_bits;
1199 	clusters = ocfs2_clusters_for_bytes(sb, pos + count) - cpos;
1200 
1201 	while (clusters) {
1202 		ret = ocfs2_get_clusters(inode, cpos, &phys_cpos, &extent_len,
1203 					 &extent_flags);
1204 		if (ret < 0) {
1205 			mlog_errno(ret);
1206 			goto out;
1207 		}
1208 
1209 		if (phys_cpos == 0 || (extent_flags & OCFS2_EXT_UNWRITTEN)) {
1210 			ret = 1;
1211 			break;
1212 		}
1213 
1214 		if (extent_len > clusters)
1215 			extent_len = clusters;
1216 
1217 		clusters -= extent_len;
1218 		cpos += extent_len;
1219 	}
1220 out:
1221 	return ret;
1222 }
1223 
1224 static int ocfs2_write_remove_suid(struct inode *inode)
1225 {
1226 	int ret;
1227 	struct buffer_head *bh = NULL;
1228 
1229 	ret = ocfs2_read_inode_block(inode, &bh);
1230 	if (ret < 0) {
1231 		mlog_errno(ret);
1232 		goto out;
1233 	}
1234 
1235 	ret =  __ocfs2_write_remove_suid(inode, bh);
1236 out:
1237 	brelse(bh);
1238 	return ret;
1239 }
1240 
1241 /*
1242  * Allocate enough extents to cover the region starting at byte offset
1243  * start for len bytes. Existing extents are skipped, any extents
1244  * added are marked as "unwritten".
1245  */
1246 static int ocfs2_allocate_unwritten_extents(struct inode *inode,
1247 					    u64 start, u64 len)
1248 {
1249 	int ret;
1250 	u32 cpos, phys_cpos, clusters, alloc_size;
1251 	u64 end = start + len;
1252 	struct buffer_head *di_bh = NULL;
1253 
1254 	if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
1255 		ret = ocfs2_read_inode_block(inode, &di_bh);
1256 		if (ret) {
1257 			mlog_errno(ret);
1258 			goto out;
1259 		}
1260 
1261 		/*
1262 		 * Nothing to do if the requested reservation range
1263 		 * fits within the inode.
1264 		 */
1265 		if (ocfs2_size_fits_inline_data(di_bh, end))
1266 			goto out;
1267 
1268 		ret = ocfs2_convert_inline_data_to_extents(inode, di_bh);
1269 		if (ret) {
1270 			mlog_errno(ret);
1271 			goto out;
1272 		}
1273 	}
1274 
1275 	/*
1276 	 * We consider both start and len to be inclusive.
1277 	 */
1278 	cpos = start >> OCFS2_SB(inode->i_sb)->s_clustersize_bits;
1279 	clusters = ocfs2_clusters_for_bytes(inode->i_sb, start + len);
1280 	clusters -= cpos;
1281 
1282 	while (clusters) {
1283 		ret = ocfs2_get_clusters(inode, cpos, &phys_cpos,
1284 					 &alloc_size, NULL);
1285 		if (ret) {
1286 			mlog_errno(ret);
1287 			goto out;
1288 		}
1289 
1290 		/*
1291 		 * Hole or existing extent len can be arbitrary, so
1292 		 * cap it to our own allocation request.
1293 		 */
1294 		if (alloc_size > clusters)
1295 			alloc_size = clusters;
1296 
1297 		if (phys_cpos) {
1298 			/*
1299 			 * We already have an allocation at this
1300 			 * region so we can safely skip it.
1301 			 */
1302 			goto next;
1303 		}
1304 
1305 		ret = __ocfs2_extend_allocation(inode, cpos, alloc_size, 1);
1306 		if (ret) {
1307 			if (ret != -ENOSPC)
1308 				mlog_errno(ret);
1309 			goto out;
1310 		}
1311 
1312 next:
1313 		cpos += alloc_size;
1314 		clusters -= alloc_size;
1315 	}
1316 
1317 	ret = 0;
1318 out:
1319 
1320 	brelse(di_bh);
1321 	return ret;
1322 }
1323 
1324 /*
1325  * Truncate a byte range, avoiding pages within partial clusters. This
1326  * preserves those pages for the zeroing code to write to.
1327  */
1328 static void ocfs2_truncate_cluster_pages(struct inode *inode, u64 byte_start,
1329 					 u64 byte_len)
1330 {
1331 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1332 	loff_t start, end;
1333 	struct address_space *mapping = inode->i_mapping;
1334 
1335 	start = (loff_t)ocfs2_align_bytes_to_clusters(inode->i_sb, byte_start);
1336 	end = byte_start + byte_len;
1337 	end = end & ~(osb->s_clustersize - 1);
1338 
1339 	if (start < end) {
1340 		unmap_mapping_range(mapping, start, end - start, 0);
1341 		truncate_inode_pages_range(mapping, start, end - 1);
1342 	}
1343 }
1344 
1345 static int ocfs2_zero_partial_clusters(struct inode *inode,
1346 				       u64 start, u64 len)
1347 {
1348 	int ret = 0;
1349 	u64 tmpend, end = start + len;
1350 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1351 	unsigned int csize = osb->s_clustersize;
1352 	handle_t *handle;
1353 
1354 	/*
1355 	 * The "start" and "end" values are NOT necessarily part of
1356 	 * the range whose allocation is being deleted. Rather, this
1357 	 * is what the user passed in with the request. We must zero
1358 	 * partial clusters here. There's no need to worry about
1359 	 * physical allocation - the zeroing code knows to skip holes.
1360 	 */
1361 	mlog(0, "byte start: %llu, end: %llu\n",
1362 	     (unsigned long long)start, (unsigned long long)end);
1363 
1364 	/*
1365 	 * If both edges are on a cluster boundary then there's no
1366 	 * zeroing required as the region is part of the allocation to
1367 	 * be truncated.
1368 	 */
1369 	if ((start & (csize - 1)) == 0 && (end & (csize - 1)) == 0)
1370 		goto out;
1371 
1372 	handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
1373 	if (IS_ERR(handle)) {
1374 		ret = PTR_ERR(handle);
1375 		mlog_errno(ret);
1376 		goto out;
1377 	}
1378 
1379 	/*
1380 	 * We want to get the byte offset of the end of the 1st cluster.
1381 	 */
1382 	tmpend = (u64)osb->s_clustersize + (start & ~(osb->s_clustersize - 1));
1383 	if (tmpend > end)
1384 		tmpend = end;
1385 
1386 	mlog(0, "1st range: start: %llu, tmpend: %llu\n",
1387 	     (unsigned long long)start, (unsigned long long)tmpend);
1388 
1389 	ret = ocfs2_zero_range_for_truncate(inode, handle, start, tmpend);
1390 	if (ret)
1391 		mlog_errno(ret);
1392 
1393 	if (tmpend < end) {
1394 		/*
1395 		 * This may make start and end equal, but the zeroing
1396 		 * code will skip any work in that case so there's no
1397 		 * need to catch it up here.
1398 		 */
1399 		start = end & ~(osb->s_clustersize - 1);
1400 
1401 		mlog(0, "2nd range: start: %llu, end: %llu\n",
1402 		     (unsigned long long)start, (unsigned long long)end);
1403 
1404 		ret = ocfs2_zero_range_for_truncate(inode, handle, start, end);
1405 		if (ret)
1406 			mlog_errno(ret);
1407 	}
1408 
1409 	ocfs2_commit_trans(osb, handle);
1410 out:
1411 	return ret;
1412 }
1413 
1414 static int ocfs2_find_rec(struct ocfs2_extent_list *el, u32 pos)
1415 {
1416 	int i;
1417 	struct ocfs2_extent_rec *rec = NULL;
1418 
1419 	for (i = le16_to_cpu(el->l_next_free_rec) - 1; i >= 0; i--) {
1420 
1421 		rec = &el->l_recs[i];
1422 
1423 		if (le32_to_cpu(rec->e_cpos) < pos)
1424 			break;
1425 	}
1426 
1427 	return i;
1428 }
1429 
1430 /*
1431  * Helper to calculate the punching pos and length in one run, we handle the
1432  * following three cases in order:
1433  *
1434  * - remove the entire record
1435  * - remove a partial record
1436  * - no record needs to be removed (hole-punching completed)
1437 */
1438 static void ocfs2_calc_trunc_pos(struct inode *inode,
1439 				 struct ocfs2_extent_list *el,
1440 				 struct ocfs2_extent_rec *rec,
1441 				 u32 trunc_start, u32 *trunc_cpos,
1442 				 u32 *trunc_len, u32 *trunc_end,
1443 				 u64 *blkno, int *done)
1444 {
1445 	int ret = 0;
1446 	u32 coff, range;
1447 
1448 	range = le32_to_cpu(rec->e_cpos) + ocfs2_rec_clusters(el, rec);
1449 
1450 	if (le32_to_cpu(rec->e_cpos) >= trunc_start) {
1451 		*trunc_cpos = le32_to_cpu(rec->e_cpos);
1452 		/*
1453 		 * Skip holes if any.
1454 		 */
1455 		if (range < *trunc_end)
1456 			*trunc_end = range;
1457 		*trunc_len = *trunc_end - le32_to_cpu(rec->e_cpos);
1458 		*blkno = le64_to_cpu(rec->e_blkno);
1459 		*trunc_end = le32_to_cpu(rec->e_cpos);
1460 	} else if (range > trunc_start) {
1461 		*trunc_cpos = trunc_start;
1462 		*trunc_len = *trunc_end - trunc_start;
1463 		coff = trunc_start - le32_to_cpu(rec->e_cpos);
1464 		*blkno = le64_to_cpu(rec->e_blkno) +
1465 				ocfs2_clusters_to_blocks(inode->i_sb, coff);
1466 		*trunc_end = trunc_start;
1467 	} else {
1468 		/*
1469 		 * It may have two following possibilities:
1470 		 *
1471 		 * - last record has been removed
1472 		 * - trunc_start was within a hole
1473 		 *
1474 		 * both two cases mean the completion of hole punching.
1475 		 */
1476 		ret = 1;
1477 	}
1478 
1479 	*done = ret;
1480 }
1481 
1482 static int ocfs2_remove_inode_range(struct inode *inode,
1483 				    struct buffer_head *di_bh, u64 byte_start,
1484 				    u64 byte_len)
1485 {
1486 	int ret = 0, flags = 0, done = 0, i;
1487 	u32 trunc_start, trunc_len, trunc_end, trunc_cpos, phys_cpos;
1488 	u32 cluster_in_el;
1489 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1490 	struct ocfs2_cached_dealloc_ctxt dealloc;
1491 	struct address_space *mapping = inode->i_mapping;
1492 	struct ocfs2_extent_tree et;
1493 	struct ocfs2_path *path = NULL;
1494 	struct ocfs2_extent_list *el = NULL;
1495 	struct ocfs2_extent_rec *rec = NULL;
1496 	struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
1497 	u64 blkno, refcount_loc = le64_to_cpu(di->i_refcount_loc);
1498 
1499 	ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode), di_bh);
1500 	ocfs2_init_dealloc_ctxt(&dealloc);
1501 
1502 	if (byte_len == 0)
1503 		return 0;
1504 
1505 	if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
1506 		ret = ocfs2_truncate_inline(inode, di_bh, byte_start,
1507 					    byte_start + byte_len, 0);
1508 		if (ret) {
1509 			mlog_errno(ret);
1510 			goto out;
1511 		}
1512 		/*
1513 		 * There's no need to get fancy with the page cache
1514 		 * truncate of an inline-data inode. We're talking
1515 		 * about less than a page here, which will be cached
1516 		 * in the dinode buffer anyway.
1517 		 */
1518 		unmap_mapping_range(mapping, 0, 0, 0);
1519 		truncate_inode_pages(mapping, 0);
1520 		goto out;
1521 	}
1522 
1523 	/*
1524 	 * For reflinks, we may need to CoW 2 clusters which might be
1525 	 * partially zero'd later, if hole's start and end offset were
1526 	 * within one cluster(means is not exactly aligned to clustersize).
1527 	 */
1528 
1529 	if (OCFS2_I(inode)->ip_dyn_features & OCFS2_HAS_REFCOUNT_FL) {
1530 
1531 		ret = ocfs2_cow_file_pos(inode, di_bh, byte_start);
1532 		if (ret) {
1533 			mlog_errno(ret);
1534 			goto out;
1535 		}
1536 
1537 		ret = ocfs2_cow_file_pos(inode, di_bh, byte_start + byte_len);
1538 		if (ret) {
1539 			mlog_errno(ret);
1540 			goto out;
1541 		}
1542 	}
1543 
1544 	trunc_start = ocfs2_clusters_for_bytes(osb->sb, byte_start);
1545 	trunc_end = (byte_start + byte_len) >> osb->s_clustersize_bits;
1546 	cluster_in_el = trunc_end;
1547 
1548 	mlog(0, "Inode: %llu, start: %llu, len: %llu, cstart: %u, cend: %u\n",
1549 	     (unsigned long long)OCFS2_I(inode)->ip_blkno,
1550 	     (unsigned long long)byte_start,
1551 	     (unsigned long long)byte_len, trunc_start, trunc_end);
1552 
1553 	ret = ocfs2_zero_partial_clusters(inode, byte_start, byte_len);
1554 	if (ret) {
1555 		mlog_errno(ret);
1556 		goto out;
1557 	}
1558 
1559 	path = ocfs2_new_path_from_et(&et);
1560 	if (!path) {
1561 		ret = -ENOMEM;
1562 		mlog_errno(ret);
1563 		goto out;
1564 	}
1565 
1566 	while (trunc_end > trunc_start) {
1567 
1568 		ret = ocfs2_find_path(INODE_CACHE(inode), path,
1569 				      cluster_in_el);
1570 		if (ret) {
1571 			mlog_errno(ret);
1572 			goto out;
1573 		}
1574 
1575 		el = path_leaf_el(path);
1576 
1577 		i = ocfs2_find_rec(el, trunc_end);
1578 		/*
1579 		 * Need to go to previous extent block.
1580 		 */
1581 		if (i < 0) {
1582 			if (path->p_tree_depth == 0)
1583 				break;
1584 
1585 			ret = ocfs2_find_cpos_for_left_leaf(inode->i_sb,
1586 							    path,
1587 							    &cluster_in_el);
1588 			if (ret) {
1589 				mlog_errno(ret);
1590 				goto out;
1591 			}
1592 
1593 			/*
1594 			 * We've reached the leftmost extent block,
1595 			 * it's safe to leave.
1596 			 */
1597 			if (cluster_in_el == 0)
1598 				break;
1599 
1600 			/*
1601 			 * The 'pos' searched for previous extent block is
1602 			 * always one cluster less than actual trunc_end.
1603 			 */
1604 			trunc_end = cluster_in_el + 1;
1605 
1606 			ocfs2_reinit_path(path, 1);
1607 
1608 			continue;
1609 
1610 		} else
1611 			rec = &el->l_recs[i];
1612 
1613 		ocfs2_calc_trunc_pos(inode, el, rec, trunc_start, &trunc_cpos,
1614 				     &trunc_len, &trunc_end, &blkno, &done);
1615 		if (done)
1616 			break;
1617 
1618 		flags = rec->e_flags;
1619 		phys_cpos = ocfs2_blocks_to_clusters(inode->i_sb, blkno);
1620 
1621 		ret = ocfs2_remove_btree_range(inode, &et, trunc_cpos,
1622 					       phys_cpos, trunc_len, flags,
1623 					       &dealloc, refcount_loc);
1624 		if (ret < 0) {
1625 			mlog_errno(ret);
1626 			goto out;
1627 		}
1628 
1629 		cluster_in_el = trunc_end;
1630 
1631 		ocfs2_reinit_path(path, 1);
1632 	}
1633 
1634 	ocfs2_truncate_cluster_pages(inode, byte_start, byte_len);
1635 
1636 out:
1637 	ocfs2_schedule_truncate_log_flush(osb, 1);
1638 	ocfs2_run_deallocs(osb, &dealloc);
1639 
1640 	return ret;
1641 }
1642 
1643 /*
1644  * Parts of this function taken from xfs_change_file_space()
1645  */
1646 static int __ocfs2_change_file_space(struct file *file, struct inode *inode,
1647 				     loff_t f_pos, unsigned int cmd,
1648 				     struct ocfs2_space_resv *sr,
1649 				     int change_size)
1650 {
1651 	int ret;
1652 	s64 llen;
1653 	loff_t size;
1654 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1655 	struct buffer_head *di_bh = NULL;
1656 	handle_t *handle;
1657 	unsigned long long max_off = inode->i_sb->s_maxbytes;
1658 
1659 	if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
1660 		return -EROFS;
1661 
1662 	mutex_lock(&inode->i_mutex);
1663 
1664 	/*
1665 	 * This prevents concurrent writes on other nodes
1666 	 */
1667 	ret = ocfs2_rw_lock(inode, 1);
1668 	if (ret) {
1669 		mlog_errno(ret);
1670 		goto out;
1671 	}
1672 
1673 	ret = ocfs2_inode_lock(inode, &di_bh, 1);
1674 	if (ret) {
1675 		mlog_errno(ret);
1676 		goto out_rw_unlock;
1677 	}
1678 
1679 	if (inode->i_flags & (S_IMMUTABLE|S_APPEND)) {
1680 		ret = -EPERM;
1681 		goto out_inode_unlock;
1682 	}
1683 
1684 	switch (sr->l_whence) {
1685 	case 0: /*SEEK_SET*/
1686 		break;
1687 	case 1: /*SEEK_CUR*/
1688 		sr->l_start += f_pos;
1689 		break;
1690 	case 2: /*SEEK_END*/
1691 		sr->l_start += i_size_read(inode);
1692 		break;
1693 	default:
1694 		ret = -EINVAL;
1695 		goto out_inode_unlock;
1696 	}
1697 	sr->l_whence = 0;
1698 
1699 	llen = sr->l_len > 0 ? sr->l_len - 1 : sr->l_len;
1700 
1701 	if (sr->l_start < 0
1702 	    || sr->l_start > max_off
1703 	    || (sr->l_start + llen) < 0
1704 	    || (sr->l_start + llen) > max_off) {
1705 		ret = -EINVAL;
1706 		goto out_inode_unlock;
1707 	}
1708 	size = sr->l_start + sr->l_len;
1709 
1710 	if (cmd == OCFS2_IOC_RESVSP || cmd == OCFS2_IOC_RESVSP64) {
1711 		if (sr->l_len <= 0) {
1712 			ret = -EINVAL;
1713 			goto out_inode_unlock;
1714 		}
1715 	}
1716 
1717 	if (file && should_remove_suid(file->f_path.dentry)) {
1718 		ret = __ocfs2_write_remove_suid(inode, di_bh);
1719 		if (ret) {
1720 			mlog_errno(ret);
1721 			goto out_inode_unlock;
1722 		}
1723 	}
1724 
1725 	down_write(&OCFS2_I(inode)->ip_alloc_sem);
1726 	switch (cmd) {
1727 	case OCFS2_IOC_RESVSP:
1728 	case OCFS2_IOC_RESVSP64:
1729 		/*
1730 		 * This takes unsigned offsets, but the signed ones we
1731 		 * pass have been checked against overflow above.
1732 		 */
1733 		ret = ocfs2_allocate_unwritten_extents(inode, sr->l_start,
1734 						       sr->l_len);
1735 		break;
1736 	case OCFS2_IOC_UNRESVSP:
1737 	case OCFS2_IOC_UNRESVSP64:
1738 		ret = ocfs2_remove_inode_range(inode, di_bh, sr->l_start,
1739 					       sr->l_len);
1740 		break;
1741 	default:
1742 		ret = -EINVAL;
1743 	}
1744 	up_write(&OCFS2_I(inode)->ip_alloc_sem);
1745 	if (ret) {
1746 		mlog_errno(ret);
1747 		goto out_inode_unlock;
1748 	}
1749 
1750 	/*
1751 	 * We update c/mtime for these changes
1752 	 */
1753 	handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS);
1754 	if (IS_ERR(handle)) {
1755 		ret = PTR_ERR(handle);
1756 		mlog_errno(ret);
1757 		goto out_inode_unlock;
1758 	}
1759 
1760 	if (change_size && i_size_read(inode) < size)
1761 		i_size_write(inode, size);
1762 
1763 	inode->i_ctime = inode->i_mtime = CURRENT_TIME;
1764 	ret = ocfs2_mark_inode_dirty(handle, inode, di_bh);
1765 	if (ret < 0)
1766 		mlog_errno(ret);
1767 
1768 	ocfs2_commit_trans(osb, handle);
1769 
1770 out_inode_unlock:
1771 	brelse(di_bh);
1772 	ocfs2_inode_unlock(inode, 1);
1773 out_rw_unlock:
1774 	ocfs2_rw_unlock(inode, 1);
1775 
1776 out:
1777 	mutex_unlock(&inode->i_mutex);
1778 	return ret;
1779 }
1780 
1781 int ocfs2_change_file_space(struct file *file, unsigned int cmd,
1782 			    struct ocfs2_space_resv *sr)
1783 {
1784 	struct inode *inode = file->f_path.dentry->d_inode;
1785 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1786 
1787 	if ((cmd == OCFS2_IOC_RESVSP || cmd == OCFS2_IOC_RESVSP64) &&
1788 	    !ocfs2_writes_unwritten_extents(osb))
1789 		return -ENOTTY;
1790 	else if ((cmd == OCFS2_IOC_UNRESVSP || cmd == OCFS2_IOC_UNRESVSP64) &&
1791 		 !ocfs2_sparse_alloc(osb))
1792 		return -ENOTTY;
1793 
1794 	if (!S_ISREG(inode->i_mode))
1795 		return -EINVAL;
1796 
1797 	if (!(file->f_mode & FMODE_WRITE))
1798 		return -EBADF;
1799 
1800 	return __ocfs2_change_file_space(file, inode, file->f_pos, cmd, sr, 0);
1801 }
1802 
1803 static long ocfs2_fallocate(struct inode *inode, int mode, loff_t offset,
1804 			    loff_t len)
1805 {
1806 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
1807 	struct ocfs2_space_resv sr;
1808 	int change_size = 1;
1809 
1810 	if (!ocfs2_writes_unwritten_extents(osb))
1811 		return -EOPNOTSUPP;
1812 
1813 	if (S_ISDIR(inode->i_mode))
1814 		return -ENODEV;
1815 
1816 	if (mode & FALLOC_FL_KEEP_SIZE)
1817 		change_size = 0;
1818 
1819 	sr.l_whence = 0;
1820 	sr.l_start = (s64)offset;
1821 	sr.l_len = (s64)len;
1822 
1823 	return __ocfs2_change_file_space(NULL, inode, offset,
1824 					 OCFS2_IOC_RESVSP64, &sr, change_size);
1825 }
1826 
1827 int ocfs2_check_range_for_refcount(struct inode *inode, loff_t pos,
1828 				   size_t count)
1829 {
1830 	int ret = 0;
1831 	unsigned int extent_flags;
1832 	u32 cpos, clusters, extent_len, phys_cpos;
1833 	struct super_block *sb = inode->i_sb;
1834 
1835 	if (!ocfs2_refcount_tree(OCFS2_SB(inode->i_sb)) ||
1836 	    !(OCFS2_I(inode)->ip_dyn_features & OCFS2_HAS_REFCOUNT_FL) ||
1837 	    OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
1838 		return 0;
1839 
1840 	cpos = pos >> OCFS2_SB(sb)->s_clustersize_bits;
1841 	clusters = ocfs2_clusters_for_bytes(sb, pos + count) - cpos;
1842 
1843 	while (clusters) {
1844 		ret = ocfs2_get_clusters(inode, cpos, &phys_cpos, &extent_len,
1845 					 &extent_flags);
1846 		if (ret < 0) {
1847 			mlog_errno(ret);
1848 			goto out;
1849 		}
1850 
1851 		if (phys_cpos && (extent_flags & OCFS2_EXT_REFCOUNTED)) {
1852 			ret = 1;
1853 			break;
1854 		}
1855 
1856 		if (extent_len > clusters)
1857 			extent_len = clusters;
1858 
1859 		clusters -= extent_len;
1860 		cpos += extent_len;
1861 	}
1862 out:
1863 	return ret;
1864 }
1865 
1866 static int ocfs2_prepare_inode_for_refcount(struct inode *inode,
1867 					    loff_t pos, size_t count,
1868 					    int *meta_level)
1869 {
1870 	int ret;
1871 	struct buffer_head *di_bh = NULL;
1872 	u32 cpos = pos >> OCFS2_SB(inode->i_sb)->s_clustersize_bits;
1873 	u32 clusters =
1874 		ocfs2_clusters_for_bytes(inode->i_sb, pos + count) - cpos;
1875 
1876 	ret = ocfs2_inode_lock(inode, &di_bh, 1);
1877 	if (ret) {
1878 		mlog_errno(ret);
1879 		goto out;
1880 	}
1881 
1882 	*meta_level = 1;
1883 
1884 	ret = ocfs2_refcount_cow(inode, di_bh, cpos, clusters, UINT_MAX);
1885 	if (ret)
1886 		mlog_errno(ret);
1887 out:
1888 	brelse(di_bh);
1889 	return ret;
1890 }
1891 
1892 static int ocfs2_prepare_inode_for_write(struct dentry *dentry,
1893 					 loff_t *ppos,
1894 					 size_t count,
1895 					 int appending,
1896 					 int *direct_io,
1897 					 int *has_refcount)
1898 {
1899 	int ret = 0, meta_level = 0;
1900 	struct inode *inode = dentry->d_inode;
1901 	loff_t saved_pos, end;
1902 
1903 	/*
1904 	 * We start with a read level meta lock and only jump to an ex
1905 	 * if we need to make modifications here.
1906 	 */
1907 	for(;;) {
1908 		ret = ocfs2_inode_lock(inode, NULL, meta_level);
1909 		if (ret < 0) {
1910 			meta_level = -1;
1911 			mlog_errno(ret);
1912 			goto out;
1913 		}
1914 
1915 		/* Clear suid / sgid if necessary. We do this here
1916 		 * instead of later in the write path because
1917 		 * remove_suid() calls ->setattr without any hint that
1918 		 * we may have already done our cluster locking. Since
1919 		 * ocfs2_setattr() *must* take cluster locks to
1920 		 * proceeed, this will lead us to recursively lock the
1921 		 * inode. There's also the dinode i_size state which
1922 		 * can be lost via setattr during extending writes (we
1923 		 * set inode->i_size at the end of a write. */
1924 		if (should_remove_suid(dentry)) {
1925 			if (meta_level == 0) {
1926 				ocfs2_inode_unlock(inode, meta_level);
1927 				meta_level = 1;
1928 				continue;
1929 			}
1930 
1931 			ret = ocfs2_write_remove_suid(inode);
1932 			if (ret < 0) {
1933 				mlog_errno(ret);
1934 				goto out_unlock;
1935 			}
1936 		}
1937 
1938 		/* work on a copy of ppos until we're sure that we won't have
1939 		 * to recalculate it due to relocking. */
1940 		if (appending) {
1941 			saved_pos = i_size_read(inode);
1942 			mlog(0, "O_APPEND: inode->i_size=%llu\n", saved_pos);
1943 		} else {
1944 			saved_pos = *ppos;
1945 		}
1946 
1947 		end = saved_pos + count;
1948 
1949 		ret = ocfs2_check_range_for_refcount(inode, saved_pos, count);
1950 		if (ret == 1) {
1951 			ocfs2_inode_unlock(inode, meta_level);
1952 			meta_level = -1;
1953 
1954 			ret = ocfs2_prepare_inode_for_refcount(inode,
1955 							       saved_pos,
1956 							       count,
1957 							       &meta_level);
1958 			if (has_refcount)
1959 				*has_refcount = 1;
1960 			if (direct_io)
1961 				*direct_io = 0;
1962 		}
1963 
1964 		if (ret < 0) {
1965 			mlog_errno(ret);
1966 			goto out_unlock;
1967 		}
1968 
1969 		/*
1970 		 * Skip the O_DIRECT checks if we don't need
1971 		 * them.
1972 		 */
1973 		if (!direct_io || !(*direct_io))
1974 			break;
1975 
1976 		/*
1977 		 * There's no sane way to do direct writes to an inode
1978 		 * with inline data.
1979 		 */
1980 		if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
1981 			*direct_io = 0;
1982 			break;
1983 		}
1984 
1985 		/*
1986 		 * Allowing concurrent direct writes means
1987 		 * i_size changes wouldn't be synchronized, so
1988 		 * one node could wind up truncating another
1989 		 * nodes writes.
1990 		 */
1991 		if (end > i_size_read(inode)) {
1992 			*direct_io = 0;
1993 			break;
1994 		}
1995 
1996 		/*
1997 		 * We don't fill holes during direct io, so
1998 		 * check for them here. If any are found, the
1999 		 * caller will have to retake some cluster
2000 		 * locks and initiate the io as buffered.
2001 		 */
2002 		ret = ocfs2_check_range_for_holes(inode, saved_pos, count);
2003 		if (ret == 1) {
2004 			*direct_io = 0;
2005 			ret = 0;
2006 		} else if (ret < 0)
2007 			mlog_errno(ret);
2008 		break;
2009 	}
2010 
2011 	if (appending)
2012 		*ppos = saved_pos;
2013 
2014 out_unlock:
2015 	if (meta_level >= 0)
2016 		ocfs2_inode_unlock(inode, meta_level);
2017 
2018 out:
2019 	return ret;
2020 }
2021 
2022 static ssize_t ocfs2_file_aio_write(struct kiocb *iocb,
2023 				    const struct iovec *iov,
2024 				    unsigned long nr_segs,
2025 				    loff_t pos)
2026 {
2027 	int ret, direct_io, appending, rw_level, have_alloc_sem  = 0;
2028 	int can_do_direct, has_refcount = 0;
2029 	ssize_t written = 0;
2030 	size_t ocount;		/* original count */
2031 	size_t count;		/* after file limit checks */
2032 	loff_t old_size, *ppos = &iocb->ki_pos;
2033 	u32 old_clusters;
2034 	struct file *file = iocb->ki_filp;
2035 	struct inode *inode = file->f_path.dentry->d_inode;
2036 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
2037 
2038 	mlog_entry("(0x%p, %u, '%.*s')\n", file,
2039 		   (unsigned int)nr_segs,
2040 		   file->f_path.dentry->d_name.len,
2041 		   file->f_path.dentry->d_name.name);
2042 
2043 	if (iocb->ki_left == 0)
2044 		return 0;
2045 
2046 	vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
2047 
2048 	appending = file->f_flags & O_APPEND ? 1 : 0;
2049 	direct_io = file->f_flags & O_DIRECT ? 1 : 0;
2050 
2051 	mutex_lock(&inode->i_mutex);
2052 
2053 relock:
2054 	/* to match setattr's i_mutex -> i_alloc_sem -> rw_lock ordering */
2055 	if (direct_io) {
2056 		down_read(&inode->i_alloc_sem);
2057 		have_alloc_sem = 1;
2058 	}
2059 
2060 	/* concurrent O_DIRECT writes are allowed */
2061 	rw_level = !direct_io;
2062 	ret = ocfs2_rw_lock(inode, rw_level);
2063 	if (ret < 0) {
2064 		mlog_errno(ret);
2065 		goto out_sems;
2066 	}
2067 
2068 	can_do_direct = direct_io;
2069 	ret = ocfs2_prepare_inode_for_write(file->f_path.dentry, ppos,
2070 					    iocb->ki_left, appending,
2071 					    &can_do_direct, &has_refcount);
2072 	if (ret < 0) {
2073 		mlog_errno(ret);
2074 		goto out;
2075 	}
2076 
2077 	/*
2078 	 * We can't complete the direct I/O as requested, fall back to
2079 	 * buffered I/O.
2080 	 */
2081 	if (direct_io && !can_do_direct) {
2082 		ocfs2_rw_unlock(inode, rw_level);
2083 		up_read(&inode->i_alloc_sem);
2084 
2085 		have_alloc_sem = 0;
2086 		rw_level = -1;
2087 
2088 		direct_io = 0;
2089 		goto relock;
2090 	}
2091 
2092 	/*
2093 	 * To later detect whether a journal commit for sync writes is
2094 	 * necessary, we sample i_size, and cluster count here.
2095 	 */
2096 	old_size = i_size_read(inode);
2097 	old_clusters = OCFS2_I(inode)->ip_clusters;
2098 
2099 	/* communicate with ocfs2_dio_end_io */
2100 	ocfs2_iocb_set_rw_locked(iocb, rw_level);
2101 
2102 	ret = generic_segment_checks(iov, &nr_segs, &ocount,
2103 				     VERIFY_READ);
2104 	if (ret)
2105 		goto out_dio;
2106 
2107 	count = ocount;
2108 	ret = generic_write_checks(file, ppos, &count,
2109 				   S_ISBLK(inode->i_mode));
2110 	if (ret)
2111 		goto out_dio;
2112 
2113 	if (direct_io) {
2114 		written = generic_file_direct_write(iocb, iov, &nr_segs, *ppos,
2115 						    ppos, count, ocount);
2116 		if (written < 0) {
2117 			/*
2118 			 * direct write may have instantiated a few
2119 			 * blocks outside i_size. Trim these off again.
2120 			 * Don't need i_size_read because we hold i_mutex.
2121 			 *
2122 			 * XXX(hch): this looks buggy because ocfs2 did not
2123 			 * actually implement ->truncate.  Take a look at
2124 			 * the new truncate sequence and update this accordingly
2125 			 */
2126 			if (*ppos + count > inode->i_size)
2127 				simple_setsize(inode, inode->i_size);
2128 			ret = written;
2129 			goto out_dio;
2130 		}
2131 	} else {
2132 		current->backing_dev_info = file->f_mapping->backing_dev_info;
2133 		written = generic_file_buffered_write(iocb, iov, nr_segs, *ppos,
2134 						      ppos, count, 0);
2135 		current->backing_dev_info = NULL;
2136 	}
2137 
2138 out_dio:
2139 	/* buffered aio wouldn't have proper lock coverage today */
2140 	BUG_ON(ret == -EIOCBQUEUED && !(file->f_flags & O_DIRECT));
2141 
2142 	if (((file->f_flags & O_DSYNC) && !direct_io) || IS_SYNC(inode) ||
2143 	    ((file->f_flags & O_DIRECT) && has_refcount)) {
2144 		ret = filemap_fdatawrite_range(file->f_mapping, pos,
2145 					       pos + count - 1);
2146 		if (ret < 0)
2147 			written = ret;
2148 
2149 		if (!ret && ((old_size != i_size_read(inode)) ||
2150 			     (old_clusters != OCFS2_I(inode)->ip_clusters) ||
2151 			     has_refcount)) {
2152 			ret = jbd2_journal_force_commit(osb->journal->j_journal);
2153 			if (ret < 0)
2154 				written = ret;
2155 		}
2156 
2157 		if (!ret)
2158 			ret = filemap_fdatawait_range(file->f_mapping, pos,
2159 						      pos + count - 1);
2160 	}
2161 
2162 	/*
2163 	 * deep in g_f_a_w_n()->ocfs2_direct_IO we pass in a ocfs2_dio_end_io
2164 	 * function pointer which is called when o_direct io completes so that
2165 	 * it can unlock our rw lock.  (it's the clustered equivalent of
2166 	 * i_alloc_sem; protects truncate from racing with pending ios).
2167 	 * Unfortunately there are error cases which call end_io and others
2168 	 * that don't.  so we don't have to unlock the rw_lock if either an
2169 	 * async dio is going to do it in the future or an end_io after an
2170 	 * error has already done it.
2171 	 */
2172 	if ((ret == -EIOCBQUEUED) || (!ocfs2_iocb_is_rw_locked(iocb))) {
2173 		rw_level = -1;
2174 		have_alloc_sem = 0;
2175 	}
2176 
2177 out:
2178 	if (rw_level != -1)
2179 		ocfs2_rw_unlock(inode, rw_level);
2180 
2181 out_sems:
2182 	if (have_alloc_sem)
2183 		up_read(&inode->i_alloc_sem);
2184 
2185 	mutex_unlock(&inode->i_mutex);
2186 
2187 	if (written)
2188 		ret = written;
2189 	mlog_exit(ret);
2190 	return ret;
2191 }
2192 
2193 static int ocfs2_splice_to_file(struct pipe_inode_info *pipe,
2194 				struct file *out,
2195 				struct splice_desc *sd)
2196 {
2197 	int ret;
2198 
2199 	ret = ocfs2_prepare_inode_for_write(out->f_path.dentry,	&sd->pos,
2200 					    sd->total_len, 0, NULL, NULL);
2201 	if (ret < 0) {
2202 		mlog_errno(ret);
2203 		return ret;
2204 	}
2205 
2206 	return splice_from_pipe_feed(pipe, sd, pipe_to_file);
2207 }
2208 
2209 static ssize_t ocfs2_file_splice_write(struct pipe_inode_info *pipe,
2210 				       struct file *out,
2211 				       loff_t *ppos,
2212 				       size_t len,
2213 				       unsigned int flags)
2214 {
2215 	int ret;
2216 	struct address_space *mapping = out->f_mapping;
2217 	struct inode *inode = mapping->host;
2218 	struct splice_desc sd = {
2219 		.total_len = len,
2220 		.flags = flags,
2221 		.pos = *ppos,
2222 		.u.file = out,
2223 	};
2224 
2225 	mlog_entry("(0x%p, 0x%p, %u, '%.*s')\n", out, pipe,
2226 		   (unsigned int)len,
2227 		   out->f_path.dentry->d_name.len,
2228 		   out->f_path.dentry->d_name.name);
2229 
2230 	if (pipe->inode)
2231 		mutex_lock_nested(&pipe->inode->i_mutex, I_MUTEX_PARENT);
2232 
2233 	splice_from_pipe_begin(&sd);
2234 	do {
2235 		ret = splice_from_pipe_next(pipe, &sd);
2236 		if (ret <= 0)
2237 			break;
2238 
2239 		mutex_lock_nested(&inode->i_mutex, I_MUTEX_CHILD);
2240 		ret = ocfs2_rw_lock(inode, 1);
2241 		if (ret < 0)
2242 			mlog_errno(ret);
2243 		else {
2244 			ret = ocfs2_splice_to_file(pipe, out, &sd);
2245 			ocfs2_rw_unlock(inode, 1);
2246 		}
2247 		mutex_unlock(&inode->i_mutex);
2248 	} while (ret > 0);
2249 	splice_from_pipe_end(pipe, &sd);
2250 
2251 	if (pipe->inode)
2252 		mutex_unlock(&pipe->inode->i_mutex);
2253 
2254 	if (sd.num_spliced)
2255 		ret = sd.num_spliced;
2256 
2257 	if (ret > 0) {
2258 		unsigned long nr_pages;
2259 		int err;
2260 
2261 		nr_pages = (ret + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
2262 
2263 		err = generic_write_sync(out, *ppos, ret);
2264 		if (err)
2265 			ret = err;
2266 		else
2267 			*ppos += ret;
2268 
2269 		balance_dirty_pages_ratelimited_nr(mapping, nr_pages);
2270 	}
2271 
2272 	mlog_exit(ret);
2273 	return ret;
2274 }
2275 
2276 static ssize_t ocfs2_file_splice_read(struct file *in,
2277 				      loff_t *ppos,
2278 				      struct pipe_inode_info *pipe,
2279 				      size_t len,
2280 				      unsigned int flags)
2281 {
2282 	int ret = 0, lock_level = 0;
2283 	struct inode *inode = in->f_path.dentry->d_inode;
2284 
2285 	mlog_entry("(0x%p, 0x%p, %u, '%.*s')\n", in, pipe,
2286 		   (unsigned int)len,
2287 		   in->f_path.dentry->d_name.len,
2288 		   in->f_path.dentry->d_name.name);
2289 
2290 	/*
2291 	 * See the comment in ocfs2_file_aio_read()
2292 	 */
2293 	ret = ocfs2_inode_lock_atime(inode, in->f_vfsmnt, &lock_level);
2294 	if (ret < 0) {
2295 		mlog_errno(ret);
2296 		goto bail;
2297 	}
2298 	ocfs2_inode_unlock(inode, lock_level);
2299 
2300 	ret = generic_file_splice_read(in, ppos, pipe, len, flags);
2301 
2302 bail:
2303 	mlog_exit(ret);
2304 	return ret;
2305 }
2306 
2307 static ssize_t ocfs2_file_aio_read(struct kiocb *iocb,
2308 				   const struct iovec *iov,
2309 				   unsigned long nr_segs,
2310 				   loff_t pos)
2311 {
2312 	int ret = 0, rw_level = -1, have_alloc_sem = 0, lock_level = 0;
2313 	struct file *filp = iocb->ki_filp;
2314 	struct inode *inode = filp->f_path.dentry->d_inode;
2315 
2316 	mlog_entry("(0x%p, %u, '%.*s')\n", filp,
2317 		   (unsigned int)nr_segs,
2318 		   filp->f_path.dentry->d_name.len,
2319 		   filp->f_path.dentry->d_name.name);
2320 
2321 	if (!inode) {
2322 		ret = -EINVAL;
2323 		mlog_errno(ret);
2324 		goto bail;
2325 	}
2326 
2327 	/*
2328 	 * buffered reads protect themselves in ->readpage().  O_DIRECT reads
2329 	 * need locks to protect pending reads from racing with truncate.
2330 	 */
2331 	if (filp->f_flags & O_DIRECT) {
2332 		down_read(&inode->i_alloc_sem);
2333 		have_alloc_sem = 1;
2334 
2335 		ret = ocfs2_rw_lock(inode, 0);
2336 		if (ret < 0) {
2337 			mlog_errno(ret);
2338 			goto bail;
2339 		}
2340 		rw_level = 0;
2341 		/* communicate with ocfs2_dio_end_io */
2342 		ocfs2_iocb_set_rw_locked(iocb, rw_level);
2343 	}
2344 
2345 	/*
2346 	 * We're fine letting folks race truncates and extending
2347 	 * writes with read across the cluster, just like they can
2348 	 * locally. Hence no rw_lock during read.
2349 	 *
2350 	 * Take and drop the meta data lock to update inode fields
2351 	 * like i_size. This allows the checks down below
2352 	 * generic_file_aio_read() a chance of actually working.
2353 	 */
2354 	ret = ocfs2_inode_lock_atime(inode, filp->f_vfsmnt, &lock_level);
2355 	if (ret < 0) {
2356 		mlog_errno(ret);
2357 		goto bail;
2358 	}
2359 	ocfs2_inode_unlock(inode, lock_level);
2360 
2361 	ret = generic_file_aio_read(iocb, iov, nr_segs, iocb->ki_pos);
2362 	if (ret == -EINVAL)
2363 		mlog(0, "generic_file_aio_read returned -EINVAL\n");
2364 
2365 	/* buffered aio wouldn't have proper lock coverage today */
2366 	BUG_ON(ret == -EIOCBQUEUED && !(filp->f_flags & O_DIRECT));
2367 
2368 	/* see ocfs2_file_aio_write */
2369 	if (ret == -EIOCBQUEUED || !ocfs2_iocb_is_rw_locked(iocb)) {
2370 		rw_level = -1;
2371 		have_alloc_sem = 0;
2372 	}
2373 
2374 bail:
2375 	if (have_alloc_sem)
2376 		up_read(&inode->i_alloc_sem);
2377 	if (rw_level != -1)
2378 		ocfs2_rw_unlock(inode, rw_level);
2379 	mlog_exit(ret);
2380 
2381 	return ret;
2382 }
2383 
2384 const struct inode_operations ocfs2_file_iops = {
2385 	.setattr	= ocfs2_setattr,
2386 	.getattr	= ocfs2_getattr,
2387 	.permission	= ocfs2_permission,
2388 	.setxattr	= generic_setxattr,
2389 	.getxattr	= generic_getxattr,
2390 	.listxattr	= ocfs2_listxattr,
2391 	.removexattr	= generic_removexattr,
2392 	.fallocate	= ocfs2_fallocate,
2393 	.fiemap		= ocfs2_fiemap,
2394 };
2395 
2396 const struct inode_operations ocfs2_special_file_iops = {
2397 	.setattr	= ocfs2_setattr,
2398 	.getattr	= ocfs2_getattr,
2399 	.permission	= ocfs2_permission,
2400 };
2401 
2402 /*
2403  * Other than ->lock, keep ocfs2_fops and ocfs2_dops in sync with
2404  * ocfs2_fops_no_plocks and ocfs2_dops_no_plocks!
2405  */
2406 const struct file_operations ocfs2_fops = {
2407 	.llseek		= generic_file_llseek,
2408 	.read		= do_sync_read,
2409 	.write		= do_sync_write,
2410 	.mmap		= ocfs2_mmap,
2411 	.fsync		= ocfs2_sync_file,
2412 	.release	= ocfs2_file_release,
2413 	.open		= ocfs2_file_open,
2414 	.aio_read	= ocfs2_file_aio_read,
2415 	.aio_write	= ocfs2_file_aio_write,
2416 	.unlocked_ioctl	= ocfs2_ioctl,
2417 #ifdef CONFIG_COMPAT
2418 	.compat_ioctl   = ocfs2_compat_ioctl,
2419 #endif
2420 	.lock		= ocfs2_lock,
2421 	.flock		= ocfs2_flock,
2422 	.splice_read	= ocfs2_file_splice_read,
2423 	.splice_write	= ocfs2_file_splice_write,
2424 };
2425 
2426 const struct file_operations ocfs2_dops = {
2427 	.llseek		= generic_file_llseek,
2428 	.read		= generic_read_dir,
2429 	.readdir	= ocfs2_readdir,
2430 	.fsync		= ocfs2_sync_file,
2431 	.release	= ocfs2_dir_release,
2432 	.open		= ocfs2_dir_open,
2433 	.unlocked_ioctl	= ocfs2_ioctl,
2434 #ifdef CONFIG_COMPAT
2435 	.compat_ioctl   = ocfs2_compat_ioctl,
2436 #endif
2437 	.lock		= ocfs2_lock,
2438 	.flock		= ocfs2_flock,
2439 };
2440 
2441 /*
2442  * POSIX-lockless variants of our file_operations.
2443  *
2444  * These will be used if the underlying cluster stack does not support
2445  * posix file locking, if the user passes the "localflocks" mount
2446  * option, or if we have a local-only fs.
2447  *
2448  * ocfs2_flock is in here because all stacks handle UNIX file locks,
2449  * so we still want it in the case of no stack support for
2450  * plocks. Internally, it will do the right thing when asked to ignore
2451  * the cluster.
2452  */
2453 const struct file_operations ocfs2_fops_no_plocks = {
2454 	.llseek		= generic_file_llseek,
2455 	.read		= do_sync_read,
2456 	.write		= do_sync_write,
2457 	.mmap		= ocfs2_mmap,
2458 	.fsync		= ocfs2_sync_file,
2459 	.release	= ocfs2_file_release,
2460 	.open		= ocfs2_file_open,
2461 	.aio_read	= ocfs2_file_aio_read,
2462 	.aio_write	= ocfs2_file_aio_write,
2463 	.unlocked_ioctl	= ocfs2_ioctl,
2464 #ifdef CONFIG_COMPAT
2465 	.compat_ioctl   = ocfs2_compat_ioctl,
2466 #endif
2467 	.flock		= ocfs2_flock,
2468 	.splice_read	= ocfs2_file_splice_read,
2469 	.splice_write	= ocfs2_file_splice_write,
2470 };
2471 
2472 const struct file_operations ocfs2_dops_no_plocks = {
2473 	.llseek		= generic_file_llseek,
2474 	.read		= generic_read_dir,
2475 	.readdir	= ocfs2_readdir,
2476 	.fsync		= ocfs2_sync_file,
2477 	.release	= ocfs2_dir_release,
2478 	.open		= ocfs2_dir_open,
2479 	.unlocked_ioctl	= ocfs2_ioctl,
2480 #ifdef CONFIG_COMPAT
2481 	.compat_ioctl   = ocfs2_compat_ioctl,
2482 #endif
2483 	.flock		= ocfs2_flock,
2484 };
2485