cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
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xfs_refcount_item.c (19715B)


      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
     24struct kmem_cache	*xfs_cui_cache;
     25struct kmem_cache	*xfs_cud_cache;
     26
     27static const struct xfs_item_ops xfs_cui_item_ops;
     28
     29static 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
     34STATIC void
     35xfs_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 */
     52STATIC void
     53xfs_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
     65STATIC void
     66xfs_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 */
     84STATIC void
     85xfs_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 */
    110STATIC void
    111xfs_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 */
    125STATIC void
    126xfs_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 */
    135STATIC struct xfs_cui_log_item *
    136xfs_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
    160static 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
    165STATIC void
    166xfs_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 */
    182STATIC void
    183xfs_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 */
    202STATIC void
    203xfs_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
    213static struct xfs_log_item *
    214xfs_cud_item_intent(
    215	struct xfs_log_item	*lip)
    216{
    217	return &CUD_ITEM(lip)->cud_cuip->cui_item;
    218}
    219
    220static 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
    229static struct xfs_cud_log_item *
    230xfs_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 */
    251static int
    252xfs_trans_log_finish_refcount_update(
    253	struct xfs_trans		*tp,
    254	struct xfs_cud_log_item		*cudp,
    255	enum xfs_refcount_intent_type	type,
    256	xfs_fsblock_t			startblock,
    257	xfs_extlen_t			blockcount,
    258	xfs_fsblock_t			*new_fsb,
    259	xfs_extlen_t			*new_len,
    260	struct xfs_btree_cur		**pcur)
    261{
    262	int				error;
    263
    264	error = xfs_refcount_finish_one(tp, type, startblock,
    265			blockcount, new_fsb, new_len, pcur);
    266
    267	/*
    268	 * Mark the transaction dirty, even on error. This ensures the
    269	 * transaction is aborted, which:
    270	 *
    271	 * 1.) releases the CUI and frees the CUD
    272	 * 2.) shuts down the filesystem
    273	 */
    274	tp->t_flags |= XFS_TRANS_DIRTY | XFS_TRANS_HAS_INTENT_DONE;
    275	set_bit(XFS_LI_DIRTY, &cudp->cud_item.li_flags);
    276
    277	return error;
    278}
    279
    280/* Sort refcount intents by AG. */
    281static int
    282xfs_refcount_update_diff_items(
    283	void				*priv,
    284	const struct list_head		*a,
    285	const struct list_head		*b)
    286{
    287	struct xfs_mount		*mp = priv;
    288	struct xfs_refcount_intent	*ra;
    289	struct xfs_refcount_intent	*rb;
    290
    291	ra = container_of(a, struct xfs_refcount_intent, ri_list);
    292	rb = container_of(b, struct xfs_refcount_intent, ri_list);
    293	return  XFS_FSB_TO_AGNO(mp, ra->ri_startblock) -
    294		XFS_FSB_TO_AGNO(mp, rb->ri_startblock);
    295}
    296
    297/* Set the phys extent flags for this reverse mapping. */
    298static void
    299xfs_trans_set_refcount_flags(
    300	struct xfs_phys_extent		*refc,
    301	enum xfs_refcount_intent_type	type)
    302{
    303	refc->pe_flags = 0;
    304	switch (type) {
    305	case XFS_REFCOUNT_INCREASE:
    306	case XFS_REFCOUNT_DECREASE:
    307	case XFS_REFCOUNT_ALLOC_COW:
    308	case XFS_REFCOUNT_FREE_COW:
    309		refc->pe_flags |= type;
    310		break;
    311	default:
    312		ASSERT(0);
    313	}
    314}
    315
    316/* Log refcount updates in the intent item. */
    317STATIC void
    318xfs_refcount_update_log_item(
    319	struct xfs_trans		*tp,
    320	struct xfs_cui_log_item		*cuip,
    321	struct xfs_refcount_intent	*refc)
    322{
    323	uint				next_extent;
    324	struct xfs_phys_extent		*ext;
    325
    326	tp->t_flags |= XFS_TRANS_DIRTY;
    327	set_bit(XFS_LI_DIRTY, &cuip->cui_item.li_flags);
    328
    329	/*
    330	 * atomic_inc_return gives us the value after the increment;
    331	 * we want to use it as an array index so we need to subtract 1 from
    332	 * it.
    333	 */
    334	next_extent = atomic_inc_return(&cuip->cui_next_extent) - 1;
    335	ASSERT(next_extent < cuip->cui_format.cui_nextents);
    336	ext = &cuip->cui_format.cui_extents[next_extent];
    337	ext->pe_startblock = refc->ri_startblock;
    338	ext->pe_len = refc->ri_blockcount;
    339	xfs_trans_set_refcount_flags(ext, refc->ri_type);
    340}
    341
    342static struct xfs_log_item *
    343xfs_refcount_update_create_intent(
    344	struct xfs_trans		*tp,
    345	struct list_head		*items,
    346	unsigned int			count,
    347	bool				sort)
    348{
    349	struct xfs_mount		*mp = tp->t_mountp;
    350	struct xfs_cui_log_item		*cuip = xfs_cui_init(mp, count);
    351	struct xfs_refcount_intent	*refc;
    352
    353	ASSERT(count > 0);
    354
    355	xfs_trans_add_item(tp, &cuip->cui_item);
    356	if (sort)
    357		list_sort(mp, items, xfs_refcount_update_diff_items);
    358	list_for_each_entry(refc, items, ri_list)
    359		xfs_refcount_update_log_item(tp, cuip, refc);
    360	return &cuip->cui_item;
    361}
    362
    363/* Get an CUD so we can process all the deferred refcount updates. */
    364static struct xfs_log_item *
    365xfs_refcount_update_create_done(
    366	struct xfs_trans		*tp,
    367	struct xfs_log_item		*intent,
    368	unsigned int			count)
    369{
    370	return &xfs_trans_get_cud(tp, CUI_ITEM(intent))->cud_item;
    371}
    372
    373/* Process a deferred refcount update. */
    374STATIC int
    375xfs_refcount_update_finish_item(
    376	struct xfs_trans		*tp,
    377	struct xfs_log_item		*done,
    378	struct list_head		*item,
    379	struct xfs_btree_cur		**state)
    380{
    381	struct xfs_refcount_intent	*refc;
    382	xfs_fsblock_t			new_fsb;
    383	xfs_extlen_t			new_aglen;
    384	int				error;
    385
    386	refc = container_of(item, struct xfs_refcount_intent, ri_list);
    387	error = xfs_trans_log_finish_refcount_update(tp, CUD_ITEM(done),
    388			refc->ri_type, refc->ri_startblock, refc->ri_blockcount,
    389			&new_fsb, &new_aglen, state);
    390
    391	/* Did we run out of reservation?  Requeue what we didn't finish. */
    392	if (!error && new_aglen > 0) {
    393		ASSERT(refc->ri_type == XFS_REFCOUNT_INCREASE ||
    394		       refc->ri_type == XFS_REFCOUNT_DECREASE);
    395		refc->ri_startblock = new_fsb;
    396		refc->ri_blockcount = new_aglen;
    397		return -EAGAIN;
    398	}
    399	kmem_cache_free(xfs_refcount_intent_cache, refc);
    400	return error;
    401}
    402
    403/* Abort all pending CUIs. */
    404STATIC void
    405xfs_refcount_update_abort_intent(
    406	struct xfs_log_item		*intent)
    407{
    408	xfs_cui_release(CUI_ITEM(intent));
    409}
    410
    411/* Cancel a deferred refcount update. */
    412STATIC void
    413xfs_refcount_update_cancel_item(
    414	struct list_head		*item)
    415{
    416	struct xfs_refcount_intent	*refc;
    417
    418	refc = container_of(item, struct xfs_refcount_intent, ri_list);
    419	kmem_cache_free(xfs_refcount_intent_cache, refc);
    420}
    421
    422const struct xfs_defer_op_type xfs_refcount_update_defer_type = {
    423	.max_items	= XFS_CUI_MAX_FAST_EXTENTS,
    424	.create_intent	= xfs_refcount_update_create_intent,
    425	.abort_intent	= xfs_refcount_update_abort_intent,
    426	.create_done	= xfs_refcount_update_create_done,
    427	.finish_item	= xfs_refcount_update_finish_item,
    428	.finish_cleanup = xfs_refcount_finish_one_cleanup,
    429	.cancel_item	= xfs_refcount_update_cancel_item,
    430};
    431
    432/* Is this recovered CUI ok? */
    433static inline bool
    434xfs_cui_validate_phys(
    435	struct xfs_mount		*mp,
    436	struct xfs_phys_extent		*refc)
    437{
    438	if (!xfs_has_reflink(mp))
    439		return false;
    440
    441	if (refc->pe_flags & ~XFS_REFCOUNT_EXTENT_FLAGS)
    442		return false;
    443
    444	switch (refc->pe_flags & XFS_REFCOUNT_EXTENT_TYPE_MASK) {
    445	case XFS_REFCOUNT_INCREASE:
    446	case XFS_REFCOUNT_DECREASE:
    447	case XFS_REFCOUNT_ALLOC_COW:
    448	case XFS_REFCOUNT_FREE_COW:
    449		break;
    450	default:
    451		return false;
    452	}
    453
    454	return xfs_verify_fsbext(mp, refc->pe_startblock, refc->pe_len);
    455}
    456
    457/*
    458 * Process a refcount update intent item that was recovered from the log.
    459 * We need to update the refcountbt.
    460 */
    461STATIC int
    462xfs_cui_item_recover(
    463	struct xfs_log_item		*lip,
    464	struct list_head		*capture_list)
    465{
    466	struct xfs_bmbt_irec		irec;
    467	struct xfs_cui_log_item		*cuip = CUI_ITEM(lip);
    468	struct xfs_phys_extent		*refc;
    469	struct xfs_cud_log_item		*cudp;
    470	struct xfs_trans		*tp;
    471	struct xfs_btree_cur		*rcur = NULL;
    472	struct xfs_mount		*mp = lip->li_log->l_mp;
    473	xfs_fsblock_t			new_fsb;
    474	xfs_extlen_t			new_len;
    475	unsigned int			refc_type;
    476	bool				requeue_only = false;
    477	enum xfs_refcount_intent_type	type;
    478	int				i;
    479	int				error = 0;
    480
    481	/*
    482	 * First check the validity of the extents described by the
    483	 * CUI.  If any are bad, then assume that all are bad and
    484	 * just toss the CUI.
    485	 */
    486	for (i = 0; i < cuip->cui_format.cui_nextents; i++) {
    487		if (!xfs_cui_validate_phys(mp,
    488					&cuip->cui_format.cui_extents[i])) {
    489			XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
    490					&cuip->cui_format,
    491					sizeof(cuip->cui_format));
    492			return -EFSCORRUPTED;
    493		}
    494	}
    495
    496	/*
    497	 * Under normal operation, refcount updates are deferred, so we
    498	 * wouldn't be adding them directly to a transaction.  All
    499	 * refcount updates manage reservation usage internally and
    500	 * dynamically by deferring work that won't fit in the
    501	 * transaction.  Normally, any work that needs to be deferred
    502	 * gets attached to the same defer_ops that scheduled the
    503	 * refcount update.  However, we're in log recovery here, so we
    504	 * use the passed in defer_ops and to finish up any work that
    505	 * doesn't fit.  We need to reserve enough blocks to handle a
    506	 * full btree split on either end of the refcount range.
    507	 */
    508	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate,
    509			mp->m_refc_maxlevels * 2, 0, XFS_TRANS_RESERVE, &tp);
    510	if (error)
    511		return error;
    512
    513	cudp = xfs_trans_get_cud(tp, cuip);
    514
    515	for (i = 0; i < cuip->cui_format.cui_nextents; i++) {
    516		refc = &cuip->cui_format.cui_extents[i];
    517		refc_type = refc->pe_flags & XFS_REFCOUNT_EXTENT_TYPE_MASK;
    518		switch (refc_type) {
    519		case XFS_REFCOUNT_INCREASE:
    520		case XFS_REFCOUNT_DECREASE:
    521		case XFS_REFCOUNT_ALLOC_COW:
    522		case XFS_REFCOUNT_FREE_COW:
    523			type = refc_type;
    524			break;
    525		default:
    526			XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, mp);
    527			error = -EFSCORRUPTED;
    528			goto abort_error;
    529		}
    530		if (requeue_only) {
    531			new_fsb = refc->pe_startblock;
    532			new_len = refc->pe_len;
    533		} else
    534			error = xfs_trans_log_finish_refcount_update(tp, cudp,
    535				type, refc->pe_startblock, refc->pe_len,
    536				&new_fsb, &new_len, &rcur);
    537		if (error == -EFSCORRUPTED)
    538			XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
    539					refc, sizeof(*refc));
    540		if (error)
    541			goto abort_error;
    542
    543		/* Requeue what we didn't finish. */
    544		if (new_len > 0) {
    545			irec.br_startblock = new_fsb;
    546			irec.br_blockcount = new_len;
    547			switch (type) {
    548			case XFS_REFCOUNT_INCREASE:
    549				xfs_refcount_increase_extent(tp, &irec);
    550				break;
    551			case XFS_REFCOUNT_DECREASE:
    552				xfs_refcount_decrease_extent(tp, &irec);
    553				break;
    554			case XFS_REFCOUNT_ALLOC_COW:
    555				xfs_refcount_alloc_cow_extent(tp,
    556						irec.br_startblock,
    557						irec.br_blockcount);
    558				break;
    559			case XFS_REFCOUNT_FREE_COW:
    560				xfs_refcount_free_cow_extent(tp,
    561						irec.br_startblock,
    562						irec.br_blockcount);
    563				break;
    564			default:
    565				ASSERT(0);
    566			}
    567			requeue_only = true;
    568		}
    569	}
    570
    571	xfs_refcount_finish_one_cleanup(tp, rcur, error);
    572	return xfs_defer_ops_capture_and_commit(tp, capture_list);
    573
    574abort_error:
    575	xfs_refcount_finish_one_cleanup(tp, rcur, error);
    576	xfs_trans_cancel(tp);
    577	return error;
    578}
    579
    580STATIC bool
    581xfs_cui_item_match(
    582	struct xfs_log_item	*lip,
    583	uint64_t		intent_id)
    584{
    585	return CUI_ITEM(lip)->cui_format.cui_id == intent_id;
    586}
    587
    588/* Relog an intent item to push the log tail forward. */
    589static struct xfs_log_item *
    590xfs_cui_item_relog(
    591	struct xfs_log_item		*intent,
    592	struct xfs_trans		*tp)
    593{
    594	struct xfs_cud_log_item		*cudp;
    595	struct xfs_cui_log_item		*cuip;
    596	struct xfs_phys_extent		*extp;
    597	unsigned int			count;
    598
    599	count = CUI_ITEM(intent)->cui_format.cui_nextents;
    600	extp = CUI_ITEM(intent)->cui_format.cui_extents;
    601
    602	tp->t_flags |= XFS_TRANS_DIRTY;
    603	cudp = xfs_trans_get_cud(tp, CUI_ITEM(intent));
    604	set_bit(XFS_LI_DIRTY, &cudp->cud_item.li_flags);
    605
    606	cuip = xfs_cui_init(tp->t_mountp, count);
    607	memcpy(cuip->cui_format.cui_extents, extp, count * sizeof(*extp));
    608	atomic_set(&cuip->cui_next_extent, count);
    609	xfs_trans_add_item(tp, &cuip->cui_item);
    610	set_bit(XFS_LI_DIRTY, &cuip->cui_item.li_flags);
    611	return &cuip->cui_item;
    612}
    613
    614static const struct xfs_item_ops xfs_cui_item_ops = {
    615	.flags		= XFS_ITEM_INTENT,
    616	.iop_size	= xfs_cui_item_size,
    617	.iop_format	= xfs_cui_item_format,
    618	.iop_unpin	= xfs_cui_item_unpin,
    619	.iop_release	= xfs_cui_item_release,
    620	.iop_recover	= xfs_cui_item_recover,
    621	.iop_match	= xfs_cui_item_match,
    622	.iop_relog	= xfs_cui_item_relog,
    623};
    624
    625/*
    626 * Copy an CUI format buffer from the given buf, and into the destination
    627 * CUI format structure.  The CUI/CUD items were designed not to need any
    628 * special alignment handling.
    629 */
    630static int
    631xfs_cui_copy_format(
    632	struct xfs_log_iovec		*buf,
    633	struct xfs_cui_log_format	*dst_cui_fmt)
    634{
    635	struct xfs_cui_log_format	*src_cui_fmt;
    636	uint				len;
    637
    638	src_cui_fmt = buf->i_addr;
    639	len = xfs_cui_log_format_sizeof(src_cui_fmt->cui_nextents);
    640
    641	if (buf->i_len == len) {
    642		memcpy(dst_cui_fmt, src_cui_fmt, len);
    643		return 0;
    644	}
    645	XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, NULL);
    646	return -EFSCORRUPTED;
    647}
    648
    649/*
    650 * This routine is called to create an in-core extent refcount update
    651 * item from the cui format structure which was logged on disk.
    652 * It allocates an in-core cui, copies the extents from the format
    653 * structure into it, and adds the cui to the AIL with the given
    654 * LSN.
    655 */
    656STATIC int
    657xlog_recover_cui_commit_pass2(
    658	struct xlog			*log,
    659	struct list_head		*buffer_list,
    660	struct xlog_recover_item	*item,
    661	xfs_lsn_t			lsn)
    662{
    663	int				error;
    664	struct xfs_mount		*mp = log->l_mp;
    665	struct xfs_cui_log_item		*cuip;
    666	struct xfs_cui_log_format	*cui_formatp;
    667
    668	cui_formatp = item->ri_buf[0].i_addr;
    669
    670	cuip = xfs_cui_init(mp, cui_formatp->cui_nextents);
    671	error = xfs_cui_copy_format(&item->ri_buf[0], &cuip->cui_format);
    672	if (error) {
    673		xfs_cui_item_free(cuip);
    674		return error;
    675	}
    676	atomic_set(&cuip->cui_next_extent, cui_formatp->cui_nextents);
    677	/*
    678	 * Insert the intent into the AIL directly and drop one reference so
    679	 * that finishing or canceling the work will drop the other.
    680	 */
    681	xfs_trans_ail_insert(log->l_ailp, &cuip->cui_item, lsn);
    682	xfs_cui_release(cuip);
    683	return 0;
    684}
    685
    686const struct xlog_recover_item_ops xlog_cui_item_ops = {
    687	.item_type		= XFS_LI_CUI,
    688	.commit_pass2		= xlog_recover_cui_commit_pass2,
    689};
    690
    691/*
    692 * This routine is called when an CUD format structure is found in a committed
    693 * transaction in the log. Its purpose is to cancel the corresponding CUI if it
    694 * was still in the log. To do this it searches the AIL for the CUI with an id
    695 * equal to that in the CUD format structure. If we find it we drop the CUD
    696 * reference, which removes the CUI from the AIL and frees it.
    697 */
    698STATIC int
    699xlog_recover_cud_commit_pass2(
    700	struct xlog			*log,
    701	struct list_head		*buffer_list,
    702	struct xlog_recover_item	*item,
    703	xfs_lsn_t			lsn)
    704{
    705	struct xfs_cud_log_format	*cud_formatp;
    706
    707	cud_formatp = item->ri_buf[0].i_addr;
    708	if (item->ri_buf[0].i_len != sizeof(struct xfs_cud_log_format)) {
    709		XFS_ERROR_REPORT(__func__, XFS_ERRLEVEL_LOW, log->l_mp);
    710		return -EFSCORRUPTED;
    711	}
    712
    713	xlog_recover_release_intent(log, XFS_LI_CUI, cud_formatp->cud_cui_id);
    714	return 0;
    715}
    716
    717const struct xlog_recover_item_ops xlog_cud_item_ops = {
    718	.item_type		= XFS_LI_CUD,
    719	.commit_pass2		= xlog_recover_cud_commit_pass2,
    720};