xref: /linux/fs/xfs/xfs_refcount_item.c (revision 60684c2bd35064043360e6f716d1b7c20e967b7d)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2016 Oracle.  All Rights Reserved.
4  * Author: Darrick J. Wong <darrick.wong@oracle.com>
5  */
6 #include "xfs.h"
7 #include "xfs_fs.h"
8 #include "xfs_format.h"
9 #include "xfs_log_format.h"
10 #include "xfs_trans_resv.h"
11 #include "xfs_bit.h"
12 #include "xfs_shared.h"
13 #include "xfs_mount.h"
14 #include "xfs_defer.h"
15 #include "xfs_trans.h"
16 #include "xfs_trans_priv.h"
17 #include "xfs_refcount_item.h"
18 #include "xfs_log.h"
19 #include "xfs_refcount.h"
20 #include "xfs_error.h"
21 #include "xfs_log_priv.h"
22 #include "xfs_log_recover.h"
23 
24 struct kmem_cache	*xfs_cui_cache;
25 struct kmem_cache	*xfs_cud_cache;
26 
27 static const struct xfs_item_ops xfs_cui_item_ops;
28 
29 static inline struct xfs_cui_log_item *CUI_ITEM(struct xfs_log_item *lip)
30 {
31 	return container_of(lip, struct xfs_cui_log_item, cui_item);
32 }
33 
34 STATIC void
35 xfs_cui_item_free(
36 	struct xfs_cui_log_item	*cuip)
37 {
38 	kmem_free(cuip->cui_item.li_lv_shadow);
39 	if (cuip->cui_format.cui_nextents > XFS_CUI_MAX_FAST_EXTENTS)
40 		kmem_free(cuip);
41 	else
42 		kmem_cache_free(xfs_cui_cache, cuip);
43 }
44 
45 /*
46  * Freeing the CUI requires that we remove it from the AIL if it has already
47  * been placed there. However, the CUI may not yet have been placed in the AIL
48  * when called by xfs_cui_release() from CUD processing due to the ordering of
49  * committed vs unpin operations in bulk insert operations. Hence the reference
50  * count to ensure only the last caller frees the CUI.
51  */
52 STATIC void
53 xfs_cui_release(
54 	struct xfs_cui_log_item	*cuip)
55 {
56 	ASSERT(atomic_read(&cuip->cui_refcount) > 0);
57 	if (!atomic_dec_and_test(&cuip->cui_refcount))
58 		return;
59 
60 	xfs_trans_ail_delete(&cuip->cui_item, 0);
61 	xfs_cui_item_free(cuip);
62 }
63 
64 
65 STATIC void
66 xfs_cui_item_size(
67 	struct xfs_log_item	*lip,
68 	int			*nvecs,
69 	int			*nbytes)
70 {
71 	struct xfs_cui_log_item	*cuip = CUI_ITEM(lip);
72 
73 	*nvecs += 1;
74 	*nbytes += xfs_cui_log_format_sizeof(cuip->cui_format.cui_nextents);
75 }
76 
77 /*
78  * This is called to fill in the vector of log iovecs for the
79  * given cui log item. We use only 1 iovec, and we point that
80  * at the cui_log_format structure embedded in the cui item.
81  * It is at this point that we assert that all of the extent
82  * slots in the cui item have been filled.
83  */
84 STATIC void
85 xfs_cui_item_format(
86 	struct xfs_log_item	*lip,
87 	struct xfs_log_vec	*lv)
88 {
89 	struct xfs_cui_log_item	*cuip = CUI_ITEM(lip);
90 	struct xfs_log_iovec	*vecp = NULL;
91 
92 	ASSERT(atomic_read(&cuip->cui_next_extent) ==
93 			cuip->cui_format.cui_nextents);
94 
95 	cuip->cui_format.cui_type = XFS_LI_CUI;
96 	cuip->cui_format.cui_size = 1;
97 
98 	xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_CUI_FORMAT, &cuip->cui_format,
99 			xfs_cui_log_format_sizeof(cuip->cui_format.cui_nextents));
100 }
101 
102 /*
103  * The unpin operation is the last place an CUI is manipulated in the log. It is
104  * either inserted in the AIL or aborted in the event of a log I/O error. In
105  * either case, the CUI transaction has been successfully committed to make it
106  * this far. Therefore, we expect whoever committed the CUI to either construct
107  * and commit the CUD or drop the CUD's reference in the event of error. Simply
108  * drop the log's CUI reference now that the log is done with it.
109  */
110 STATIC void
111 xfs_cui_item_unpin(
112 	struct xfs_log_item	*lip,
113 	int			remove)
114 {
115 	struct xfs_cui_log_item	*cuip = CUI_ITEM(lip);
116 
117 	xfs_cui_release(cuip);
118 }
119 
120 /*
121  * The CUI has been either committed or aborted if the transaction has been
122  * cancelled. If the transaction was cancelled, an CUD isn't going to be
123  * constructed and thus we free the CUI here directly.
124  */
125 STATIC void
126 xfs_cui_item_release(
127 	struct xfs_log_item	*lip)
128 {
129 	xfs_cui_release(CUI_ITEM(lip));
130 }
131 
132 /*
133  * Allocate and initialize an cui item with the given number of extents.
134  */
135 STATIC struct xfs_cui_log_item *
136 xfs_cui_init(
137 	struct xfs_mount		*mp,
138 	uint				nextents)
139 
140 {
141 	struct xfs_cui_log_item		*cuip;
142 
143 	ASSERT(nextents > 0);
144 	if (nextents > XFS_CUI_MAX_FAST_EXTENTS)
145 		cuip = kmem_zalloc(xfs_cui_log_item_sizeof(nextents),
146 				0);
147 	else
148 		cuip = kmem_cache_zalloc(xfs_cui_cache,
149 					 GFP_KERNEL | __GFP_NOFAIL);
150 
151 	xfs_log_item_init(mp, &cuip->cui_item, XFS_LI_CUI, &xfs_cui_item_ops);
152 	cuip->cui_format.cui_nextents = nextents;
153 	cuip->cui_format.cui_id = (uintptr_t)(void *)cuip;
154 	atomic_set(&cuip->cui_next_extent, 0);
155 	atomic_set(&cuip->cui_refcount, 2);
156 
157 	return cuip;
158 }
159 
160 static inline struct xfs_cud_log_item *CUD_ITEM(struct xfs_log_item *lip)
161 {
162 	return container_of(lip, struct xfs_cud_log_item, cud_item);
163 }
164 
165 STATIC void
166 xfs_cud_item_size(
167 	struct xfs_log_item	*lip,
168 	int			*nvecs,
169 	int			*nbytes)
170 {
171 	*nvecs += 1;
172 	*nbytes += sizeof(struct xfs_cud_log_format);
173 }
174 
175 /*
176  * This is called to fill in the vector of log iovecs for the
177  * given cud log item. We use only 1 iovec, and we point that
178  * at the cud_log_format structure embedded in the cud item.
179  * It is at this point that we assert that all of the extent
180  * slots in the cud item have been filled.
181  */
182 STATIC void
183 xfs_cud_item_format(
184 	struct xfs_log_item	*lip,
185 	struct xfs_log_vec	*lv)
186 {
187 	struct xfs_cud_log_item	*cudp = CUD_ITEM(lip);
188 	struct xfs_log_iovec	*vecp = NULL;
189 
190 	cudp->cud_format.cud_type = XFS_LI_CUD;
191 	cudp->cud_format.cud_size = 1;
192 
193 	xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_CUD_FORMAT, &cudp->cud_format,
194 			sizeof(struct xfs_cud_log_format));
195 }
196 
197 /*
198  * The CUD is either committed or aborted if the transaction is cancelled. If
199  * the transaction is cancelled, drop our reference to the CUI and free the
200  * CUD.
201  */
202 STATIC void
203 xfs_cud_item_release(
204 	struct xfs_log_item	*lip)
205 {
206 	struct xfs_cud_log_item	*cudp = CUD_ITEM(lip);
207 
208 	xfs_cui_release(cudp->cud_cuip);
209 	kmem_free(cudp->cud_item.li_lv_shadow);
210 	kmem_cache_free(xfs_cud_cache, cudp);
211 }
212 
213 static struct xfs_log_item *
214 xfs_cud_item_intent(
215 	struct xfs_log_item	*lip)
216 {
217 	return &CUD_ITEM(lip)->cud_cuip->cui_item;
218 }
219 
220 static const struct xfs_item_ops xfs_cud_item_ops = {
221 	.flags		= XFS_ITEM_RELEASE_WHEN_COMMITTED |
222 			  XFS_ITEM_INTENT_DONE,
223 	.iop_size	= xfs_cud_item_size,
224 	.iop_format	= xfs_cud_item_format,
225 	.iop_release	= xfs_cud_item_release,
226 	.iop_intent	= xfs_cud_item_intent,
227 };
228 
229 static struct xfs_cud_log_item *
230 xfs_trans_get_cud(
231 	struct xfs_trans		*tp,
232 	struct xfs_cui_log_item		*cuip)
233 {
234 	struct xfs_cud_log_item		*cudp;
235 
236 	cudp = kmem_cache_zalloc(xfs_cud_cache, GFP_KERNEL | __GFP_NOFAIL);
237 	xfs_log_item_init(tp->t_mountp, &cudp->cud_item, XFS_LI_CUD,
238 			  &xfs_cud_item_ops);
239 	cudp->cud_cuip = cuip;
240 	cudp->cud_format.cud_cui_id = cuip->cui_format.cui_id;
241 
242 	xfs_trans_add_item(tp, &cudp->cud_item);
243 	return cudp;
244 }
245 
246 /*
247  * Finish an refcount update and log it to the CUD. Note that the
248  * transaction is marked dirty regardless of whether the refcount
249  * update succeeds or fails to support the CUI/CUD lifecycle rules.
250  */
251 static int
252 xfs_trans_log_finish_refcount_update(
253 	struct xfs_trans		*tp,
254 	struct xfs_cud_log_item		*cudp,
255 	struct xfs_refcount_intent	*ri,
256 	struct xfs_btree_cur		**pcur)
257 {
258 	int				error;
259 
260 	error = xfs_refcount_finish_one(tp, ri, pcur);
261 
262 	/*
263 	 * Mark the transaction dirty, even on error. This ensures the
264 	 * transaction is aborted, which:
265 	 *
266 	 * 1.) releases the CUI and frees the CUD
267 	 * 2.) shuts down the filesystem
268 	 */
269 	tp->t_flags |= XFS_TRANS_DIRTY | XFS_TRANS_HAS_INTENT_DONE;
270 	set_bit(XFS_LI_DIRTY, &cudp->cud_item.li_flags);
271 
272 	return error;
273 }
274 
275 /* Sort refcount intents by AG. */
276 static int
277 xfs_refcount_update_diff_items(
278 	void				*priv,
279 	const struct list_head		*a,
280 	const struct list_head		*b)
281 {
282 	struct xfs_mount		*mp = priv;
283 	struct xfs_refcount_intent	*ra;
284 	struct xfs_refcount_intent	*rb;
285 
286 	ra = container_of(a, struct xfs_refcount_intent, ri_list);
287 	rb = container_of(b, struct xfs_refcount_intent, ri_list);
288 	return  XFS_FSB_TO_AGNO(mp, ra->ri_startblock) -
289 		XFS_FSB_TO_AGNO(mp, rb->ri_startblock);
290 }
291 
292 /* Set the phys extent flags for this reverse mapping. */
293 static void
294 xfs_trans_set_refcount_flags(
295 	struct xfs_phys_extent		*pmap,
296 	enum xfs_refcount_intent_type	type)
297 {
298 	pmap->pe_flags = 0;
299 	switch (type) {
300 	case XFS_REFCOUNT_INCREASE:
301 	case XFS_REFCOUNT_DECREASE:
302 	case XFS_REFCOUNT_ALLOC_COW:
303 	case XFS_REFCOUNT_FREE_COW:
304 		pmap->pe_flags |= type;
305 		break;
306 	default:
307 		ASSERT(0);
308 	}
309 }
310 
311 /* Log refcount updates in the intent item. */
312 STATIC void
313 xfs_refcount_update_log_item(
314 	struct xfs_trans		*tp,
315 	struct xfs_cui_log_item		*cuip,
316 	struct xfs_refcount_intent	*ri)
317 {
318 	uint				next_extent;
319 	struct xfs_phys_extent		*pmap;
320 
321 	tp->t_flags |= XFS_TRANS_DIRTY;
322 	set_bit(XFS_LI_DIRTY, &cuip->cui_item.li_flags);
323 
324 	/*
325 	 * atomic_inc_return gives us the value after the increment;
326 	 * we want to use it as an array index so we need to subtract 1 from
327 	 * it.
328 	 */
329 	next_extent = atomic_inc_return(&cuip->cui_next_extent) - 1;
330 	ASSERT(next_extent < cuip->cui_format.cui_nextents);
331 	pmap = &cuip->cui_format.cui_extents[next_extent];
332 	pmap->pe_startblock = ri->ri_startblock;
333 	pmap->pe_len = ri->ri_blockcount;
334 	xfs_trans_set_refcount_flags(pmap, ri->ri_type);
335 }
336 
337 static struct xfs_log_item *
338 xfs_refcount_update_create_intent(
339 	struct xfs_trans		*tp,
340 	struct list_head		*items,
341 	unsigned int			count,
342 	bool				sort)
343 {
344 	struct xfs_mount		*mp = tp->t_mountp;
345 	struct xfs_cui_log_item		*cuip = xfs_cui_init(mp, count);
346 	struct xfs_refcount_intent	*ri;
347 
348 	ASSERT(count > 0);
349 
350 	xfs_trans_add_item(tp, &cuip->cui_item);
351 	if (sort)
352 		list_sort(mp, items, xfs_refcount_update_diff_items);
353 	list_for_each_entry(ri, items, ri_list)
354 		xfs_refcount_update_log_item(tp, cuip, ri);
355 	return &cuip->cui_item;
356 }
357 
358 /* Get an CUD so we can process all the deferred refcount updates. */
359 static struct xfs_log_item *
360 xfs_refcount_update_create_done(
361 	struct xfs_trans		*tp,
362 	struct xfs_log_item		*intent,
363 	unsigned int			count)
364 {
365 	return &xfs_trans_get_cud(tp, CUI_ITEM(intent))->cud_item;
366 }
367 
368 /* Process a deferred refcount update. */
369 STATIC int
370 xfs_refcount_update_finish_item(
371 	struct xfs_trans		*tp,
372 	struct xfs_log_item		*done,
373 	struct list_head		*item,
374 	struct xfs_btree_cur		**state)
375 {
376 	struct xfs_refcount_intent	*ri;
377 	int				error;
378 
379 	ri = container_of(item, struct xfs_refcount_intent, ri_list);
380 	error = xfs_trans_log_finish_refcount_update(tp, CUD_ITEM(done), ri,
381 			state);
382 
383 	/* Did we run out of reservation?  Requeue what we didn't finish. */
384 	if (!error && ri->ri_blockcount > 0) {
385 		ASSERT(ri->ri_type == XFS_REFCOUNT_INCREASE ||
386 		       ri->ri_type == XFS_REFCOUNT_DECREASE);
387 		return -EAGAIN;
388 	}
389 	kmem_cache_free(xfs_refcount_intent_cache, ri);
390 	return error;
391 }
392 
393 /* Abort all pending CUIs. */
394 STATIC void
395 xfs_refcount_update_abort_intent(
396 	struct xfs_log_item		*intent)
397 {
398 	xfs_cui_release(CUI_ITEM(intent));
399 }
400 
401 /* Cancel a deferred refcount update. */
402 STATIC void
403 xfs_refcount_update_cancel_item(
404 	struct list_head		*item)
405 {
406 	struct xfs_refcount_intent	*ri;
407 
408 	ri = container_of(item, struct xfs_refcount_intent, ri_list);
409 	kmem_cache_free(xfs_refcount_intent_cache, ri);
410 }
411 
412 const struct xfs_defer_op_type xfs_refcount_update_defer_type = {
413 	.max_items	= XFS_CUI_MAX_FAST_EXTENTS,
414 	.create_intent	= xfs_refcount_update_create_intent,
415 	.abort_intent	= xfs_refcount_update_abort_intent,
416 	.create_done	= xfs_refcount_update_create_done,
417 	.finish_item	= xfs_refcount_update_finish_item,
418 	.finish_cleanup = xfs_refcount_finish_one_cleanup,
419 	.cancel_item	= xfs_refcount_update_cancel_item,
420 };
421 
422 /* Is this recovered CUI ok? */
423 static inline bool
424 xfs_cui_validate_phys(
425 	struct xfs_mount		*mp,
426 	struct xfs_phys_extent		*pmap)
427 {
428 	if (!xfs_has_reflink(mp))
429 		return false;
430 
431 	if (pmap->pe_flags & ~XFS_REFCOUNT_EXTENT_FLAGS)
432 		return false;
433 
434 	switch (pmap->pe_flags & XFS_REFCOUNT_EXTENT_TYPE_MASK) {
435 	case XFS_REFCOUNT_INCREASE:
436 	case XFS_REFCOUNT_DECREASE:
437 	case XFS_REFCOUNT_ALLOC_COW:
438 	case XFS_REFCOUNT_FREE_COW:
439 		break;
440 	default:
441 		return false;
442 	}
443 
444 	return xfs_verify_fsbext(mp, pmap->pe_startblock, pmap->pe_len);
445 }
446 
447 /*
448  * Process a refcount update intent item that was recovered from the log.
449  * We need to update the refcountbt.
450  */
451 STATIC int
452 xfs_cui_item_recover(
453 	struct xfs_log_item		*lip,
454 	struct list_head		*capture_list)
455 {
456 	struct xfs_cui_log_item		*cuip = CUI_ITEM(lip);
457 	struct xfs_cud_log_item		*cudp;
458 	struct xfs_trans		*tp;
459 	struct xfs_btree_cur		*rcur = NULL;
460 	struct xfs_mount		*mp = lip->li_log->l_mp;
461 	unsigned int			refc_type;
462 	bool				requeue_only = false;
463 	int				i;
464 	int				error = 0;
465 
466 	/*
467 	 * First check the validity of the extents described by the
468 	 * CUI.  If any are bad, then assume that all are bad and
469 	 * just toss the CUI.
470 	 */
471 	for (i = 0; i < cuip->cui_format.cui_nextents; i++) {
472 		if (!xfs_cui_validate_phys(mp,
473 					&cuip->cui_format.cui_extents[i])) {
474 			XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
475 					&cuip->cui_format,
476 					sizeof(cuip->cui_format));
477 			return -EFSCORRUPTED;
478 		}
479 	}
480 
481 	/*
482 	 * Under normal operation, refcount updates are deferred, so we
483 	 * wouldn't be adding them directly to a transaction.  All
484 	 * refcount updates manage reservation usage internally and
485 	 * dynamically by deferring work that won't fit in the
486 	 * transaction.  Normally, any work that needs to be deferred
487 	 * gets attached to the same defer_ops that scheduled the
488 	 * refcount update.  However, we're in log recovery here, so we
489 	 * use the passed in defer_ops and to finish up any work that
490 	 * doesn't fit.  We need to reserve enough blocks to handle a
491 	 * full btree split on either end of the refcount range.
492 	 */
493 	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate,
494 			mp->m_refc_maxlevels * 2, 0, XFS_TRANS_RESERVE, &tp);
495 	if (error)
496 		return error;
497 
498 	cudp = xfs_trans_get_cud(tp, cuip);
499 
500 	for (i = 0; i < cuip->cui_format.cui_nextents; i++) {
501 		struct xfs_refcount_intent	fake = { };
502 		struct xfs_phys_extent		*pmap;
503 
504 		pmap = &cuip->cui_format.cui_extents[i];
505 		refc_type = pmap->pe_flags & XFS_REFCOUNT_EXTENT_TYPE_MASK;
506 		switch (refc_type) {
507 		case XFS_REFCOUNT_INCREASE:
508 		case XFS_REFCOUNT_DECREASE:
509 		case XFS_REFCOUNT_ALLOC_COW:
510 		case XFS_REFCOUNT_FREE_COW:
511 			fake.ri_type = refc_type;
512 			break;
513 		default:
514 			XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
515 					&cuip->cui_format,
516 					sizeof(cuip->cui_format));
517 			error = -EFSCORRUPTED;
518 			goto abort_error;
519 		}
520 
521 		fake.ri_startblock = pmap->pe_startblock;
522 		fake.ri_blockcount = pmap->pe_len;
523 		if (!requeue_only)
524 			error = xfs_trans_log_finish_refcount_update(tp, cudp,
525 					&fake, &rcur);
526 		if (error == -EFSCORRUPTED)
527 			XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
528 					&cuip->cui_format,
529 					sizeof(cuip->cui_format));
530 		if (error)
531 			goto abort_error;
532 
533 		/* Requeue what we didn't finish. */
534 		if (fake.ri_blockcount > 0) {
535 			struct xfs_bmbt_irec	irec = {
536 				.br_startblock	= fake.ri_startblock,
537 				.br_blockcount	= fake.ri_blockcount,
538 			};
539 
540 			switch (fake.ri_type) {
541 			case XFS_REFCOUNT_INCREASE:
542 				xfs_refcount_increase_extent(tp, &irec);
543 				break;
544 			case XFS_REFCOUNT_DECREASE:
545 				xfs_refcount_decrease_extent(tp, &irec);
546 				break;
547 			case XFS_REFCOUNT_ALLOC_COW:
548 				xfs_refcount_alloc_cow_extent(tp,
549 						irec.br_startblock,
550 						irec.br_blockcount);
551 				break;
552 			case XFS_REFCOUNT_FREE_COW:
553 				xfs_refcount_free_cow_extent(tp,
554 						irec.br_startblock,
555 						irec.br_blockcount);
556 				break;
557 			default:
558 				ASSERT(0);
559 			}
560 			requeue_only = true;
561 		}
562 	}
563 
564 	xfs_refcount_finish_one_cleanup(tp, rcur, error);
565 	return xfs_defer_ops_capture_and_commit(tp, capture_list);
566 
567 abort_error:
568 	xfs_refcount_finish_one_cleanup(tp, rcur, error);
569 	xfs_trans_cancel(tp);
570 	return error;
571 }
572 
573 STATIC bool
574 xfs_cui_item_match(
575 	struct xfs_log_item	*lip,
576 	uint64_t		intent_id)
577 {
578 	return CUI_ITEM(lip)->cui_format.cui_id == intent_id;
579 }
580 
581 /* Relog an intent item to push the log tail forward. */
582 static struct xfs_log_item *
583 xfs_cui_item_relog(
584 	struct xfs_log_item		*intent,
585 	struct xfs_trans		*tp)
586 {
587 	struct xfs_cud_log_item		*cudp;
588 	struct xfs_cui_log_item		*cuip;
589 	struct xfs_phys_extent		*pmap;
590 	unsigned int			count;
591 
592 	count = CUI_ITEM(intent)->cui_format.cui_nextents;
593 	pmap = CUI_ITEM(intent)->cui_format.cui_extents;
594 
595 	tp->t_flags |= XFS_TRANS_DIRTY;
596 	cudp = xfs_trans_get_cud(tp, CUI_ITEM(intent));
597 	set_bit(XFS_LI_DIRTY, &cudp->cud_item.li_flags);
598 
599 	cuip = xfs_cui_init(tp->t_mountp, count);
600 	memcpy(cuip->cui_format.cui_extents, pmap, count * sizeof(*pmap));
601 	atomic_set(&cuip->cui_next_extent, count);
602 	xfs_trans_add_item(tp, &cuip->cui_item);
603 	set_bit(XFS_LI_DIRTY, &cuip->cui_item.li_flags);
604 	return &cuip->cui_item;
605 }
606 
607 static const struct xfs_item_ops xfs_cui_item_ops = {
608 	.flags		= XFS_ITEM_INTENT,
609 	.iop_size	= xfs_cui_item_size,
610 	.iop_format	= xfs_cui_item_format,
611 	.iop_unpin	= xfs_cui_item_unpin,
612 	.iop_release	= xfs_cui_item_release,
613 	.iop_recover	= xfs_cui_item_recover,
614 	.iop_match	= xfs_cui_item_match,
615 	.iop_relog	= xfs_cui_item_relog,
616 };
617 
618 static inline void
619 xfs_cui_copy_format(
620 	struct xfs_cui_log_format	*dst,
621 	const struct xfs_cui_log_format	*src)
622 {
623 	unsigned int			i;
624 
625 	memcpy(dst, src, offsetof(struct xfs_cui_log_format, cui_extents));
626 
627 	for (i = 0; i < src->cui_nextents; i++)
628 		memcpy(&dst->cui_extents[i], &src->cui_extents[i],
629 				sizeof(struct xfs_phys_extent));
630 }
631 
632 /*
633  * This routine is called to create an in-core extent refcount update
634  * item from the cui format structure which was logged on disk.
635  * It allocates an in-core cui, copies the extents from the format
636  * structure into it, and adds the cui to the AIL with the given
637  * LSN.
638  */
639 STATIC int
640 xlog_recover_cui_commit_pass2(
641 	struct xlog			*log,
642 	struct list_head		*buffer_list,
643 	struct xlog_recover_item	*item,
644 	xfs_lsn_t			lsn)
645 {
646 	struct xfs_mount		*mp = log->l_mp;
647 	struct xfs_cui_log_item		*cuip;
648 	struct xfs_cui_log_format	*cui_formatp;
649 	size_t				len;
650 
651 	cui_formatp = item->ri_buf[0].i_addr;
652 
653 	if (item->ri_buf[0].i_len < xfs_cui_log_format_sizeof(0)) {
654 		XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
655 				item->ri_buf[0].i_addr, item->ri_buf[0].i_len);
656 		return -EFSCORRUPTED;
657 	}
658 
659 	len = xfs_cui_log_format_sizeof(cui_formatp->cui_nextents);
660 	if (item->ri_buf[0].i_len != len) {
661 		XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
662 				item->ri_buf[0].i_addr, item->ri_buf[0].i_len);
663 		return -EFSCORRUPTED;
664 	}
665 
666 	cuip = xfs_cui_init(mp, cui_formatp->cui_nextents);
667 	xfs_cui_copy_format(&cuip->cui_format, cui_formatp);
668 	atomic_set(&cuip->cui_next_extent, cui_formatp->cui_nextents);
669 	/*
670 	 * Insert the intent into the AIL directly and drop one reference so
671 	 * that finishing or canceling the work will drop the other.
672 	 */
673 	xfs_trans_ail_insert(log->l_ailp, &cuip->cui_item, lsn);
674 	xfs_cui_release(cuip);
675 	return 0;
676 }
677 
678 const struct xlog_recover_item_ops xlog_cui_item_ops = {
679 	.item_type		= XFS_LI_CUI,
680 	.commit_pass2		= xlog_recover_cui_commit_pass2,
681 };
682 
683 /*
684  * This routine is called when an CUD format structure is found in a committed
685  * transaction in the log. Its purpose is to cancel the corresponding CUI if it
686  * was still in the log. To do this it searches the AIL for the CUI with an id
687  * equal to that in the CUD format structure. If we find it we drop the CUD
688  * reference, which removes the CUI from the AIL and frees it.
689  */
690 STATIC int
691 xlog_recover_cud_commit_pass2(
692 	struct xlog			*log,
693 	struct list_head		*buffer_list,
694 	struct xlog_recover_item	*item,
695 	xfs_lsn_t			lsn)
696 {
697 	struct xfs_cud_log_format	*cud_formatp;
698 
699 	cud_formatp = item->ri_buf[0].i_addr;
700 	if (item->ri_buf[0].i_len != sizeof(struct xfs_cud_log_format)) {
701 		XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, log->l_mp,
702 				item->ri_buf[0].i_addr, item->ri_buf[0].i_len);
703 		return -EFSCORRUPTED;
704 	}
705 
706 	xlog_recover_release_intent(log, XFS_LI_CUI, cud_formatp->cud_cui_id);
707 	return 0;
708 }
709 
710 const struct xlog_recover_item_ops xlog_cud_item_ops = {
711 	.item_type		= XFS_LI_CUD,
712 	.commit_pass2		= xlog_recover_cud_commit_pass2,
713 };
714