1 files changed, 723 insertions, 0 deletions

diff --git a/fs/xfs/xfs_refcount_item.c b/fs/xfs/xfs_refcount_item.c
new file mode 100644
index 000000000..858e3e9eb
--- /dev/null
+++ b/fs/xfs/xfs_refcount_item.c
@@ -0,0 +1,723 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2016 Oracle.  All Rights Reserved.
+ * Author: Darrick J. Wong <darrick.wong@oracle.com>
+ */
+#include "xfs.h"
+#include "xfs_fs.h"
+#include "xfs_format.h"
+#include "xfs_log_format.h"
+#include "xfs_trans_resv.h"
+#include "xfs_bit.h"
+#include "xfs_shared.h"
+#include "xfs_mount.h"
+#include "xfs_defer.h"
+#include "xfs_trans.h"
+#include "xfs_trans_priv.h"
+#include "xfs_refcount_item.h"
+#include "xfs_log.h"
+#include "xfs_refcount.h"
+#include "xfs_error.h"
+#include "xfs_log_priv.h"
+#include "xfs_log_recover.h"
+
+struct kmem_cache	*xfs_cui_cache;
+struct kmem_cache	*xfs_cud_cache;
+
+static const struct xfs_item_ops xfs_cui_item_ops;
+
+static inline struct xfs_cui_log_item *CUI_ITEM(struct xfs_log_item *lip)
+{
+	return container_of(lip, struct xfs_cui_log_item, cui_item);
+}
+
+STATIC void
+xfs_cui_item_free(
+	struct xfs_cui_log_item	*cuip)
+{
+	kmem_free(cuip->cui_item.li_lv_shadow);
+	if (cuip->cui_format.cui_nextents > XFS_CUI_MAX_FAST_EXTENTS)
+		kmem_free(cuip);
+	else
+		kmem_cache_free(xfs_cui_cache, cuip);
+}
+
+/*
+ * Freeing the CUI requires that we remove it from the AIL if it has already
+ * been placed there. However, the CUI may not yet have been placed in the AIL
+ * when called by xfs_cui_release() from CUD processing due to the ordering of
+ * committed vs unpin operations in bulk insert operations. Hence the reference
+ * count to ensure only the last caller frees the CUI.
+ */
+STATIC void
+xfs_cui_release(
+	struct xfs_cui_log_item	*cuip)
+{
+	ASSERT(atomic_read(&cuip->cui_refcount) > 0);
+	if (!atomic_dec_and_test(&cuip->cui_refcount))
+		return;
+
+	xfs_trans_ail_delete(&cuip->cui_item, 0);
+	xfs_cui_item_free(cuip);
+}
+
+
+STATIC void
+xfs_cui_item_size(
+	struct xfs_log_item	*lip,
+	int			*nvecs,
+	int			*nbytes)
+{
+	struct xfs_cui_log_item	*cuip = CUI_ITEM(lip);
+
+	*nvecs += 1;
+	*nbytes += xfs_cui_log_format_sizeof(cuip->cui_format.cui_nextents);
+}
+
+/*
+ * This is called to fill in the vector of log iovecs for the
+ * given cui log item. We use only 1 iovec, and we point that
+ * at the cui_log_format structure embedded in the cui item.
+ * It is at this point that we assert that all of the extent
+ * slots in the cui item have been filled.
+ */
+STATIC void
+xfs_cui_item_format(
+	struct xfs_log_item	*lip,
+	struct xfs_log_vec	*lv)
+{
+	struct xfs_cui_log_item	*cuip = CUI_ITEM(lip);
+	struct xfs_log_iovec	*vecp = NULL;
+
+	ASSERT(atomic_read(&cuip->cui_next_extent) ==
+			cuip->cui_format.cui_nextents);
+
+	cuip->cui_format.cui_type = XFS_LI_CUI;
+	cuip->cui_format.cui_size = 1;
+
+	xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_CUI_FORMAT, &cuip->cui_format,
+			xfs_cui_log_format_sizeof(cuip->cui_format.cui_nextents));
+}
+
+/*
+ * The unpin operation is the last place an CUI is manipulated in the log. It is
+ * either inserted in the AIL or aborted in the event of a log I/O error. In
+ * either case, the CUI transaction has been successfully committed to make it
+ * this far. Therefore, we expect whoever committed the CUI to either construct
+ * and commit the CUD or drop the CUD's reference in the event of error. Simply
+ * drop the log's CUI reference now that the log is done with it.
+ */
+STATIC void
+xfs_cui_item_unpin(
+	struct xfs_log_item	*lip,
+	int			remove)
+{
+	struct xfs_cui_log_item	*cuip = CUI_ITEM(lip);
+
+	xfs_cui_release(cuip);
+}
+
+/*
+ * The CUI has been either committed or aborted if the transaction has been
+ * cancelled. If the transaction was cancelled, an CUD isn't going to be
+ * constructed and thus we free the CUI here directly.
+ */
+STATIC void
+xfs_cui_item_release(
+	struct xfs_log_item	*lip)
+{
+	xfs_cui_release(CUI_ITEM(lip));
+}
+
+/*
+ * Allocate and initialize an cui item with the given number of extents.
+ */
+STATIC struct xfs_cui_log_item *
+xfs_cui_init(
+	struct xfs_mount		*mp,
+	uint				nextents)
+
+{
+	struct xfs_cui_log_item		*cuip;
+
+	ASSERT(nextents > 0);
+	if (nextents > XFS_CUI_MAX_FAST_EXTENTS)
+		cuip = kmem_zalloc(xfs_cui_log_item_sizeof(nextents),
+				0);
+	else
+		cuip = kmem_cache_zalloc(xfs_cui_cache,
+					 GFP_KERNEL | __GFP_NOFAIL);
+
+	xfs_log_item_init(mp, &cuip->cui_item, XFS_LI_CUI, &xfs_cui_item_ops);
+	cuip->cui_format.cui_nextents = nextents;
+	cuip->cui_format.cui_id = (uintptr_t)(void *)cuip;
+	atomic_set(&cuip->cui_next_extent, 0);
+	atomic_set(&cuip->cui_refcount, 2);
+
+	return cuip;
+}
+
+static inline struct xfs_cud_log_item *CUD_ITEM(struct xfs_log_item *lip)
+{
+	return container_of(lip, struct xfs_cud_log_item, cud_item);
+}
+
+STATIC void
+xfs_cud_item_size(
+	struct xfs_log_item	*lip,
+	int			*nvecs,
+	int			*nbytes)
+{
+	*nvecs += 1;
+	*nbytes += sizeof(struct xfs_cud_log_format);
+}
+
+/*
+ * This is called to fill in the vector of log iovecs for the
+ * given cud log item. We use only 1 iovec, and we point that
+ * at the cud_log_format structure embedded in the cud item.
+ * It is at this point that we assert that all of the extent
+ * slots in the cud item have been filled.
+ */
+STATIC void
+xfs_cud_item_format(
+	struct xfs_log_item	*lip,
+	struct xfs_log_vec	*lv)
+{
+	struct xfs_cud_log_item	*cudp = CUD_ITEM(lip);
+	struct xfs_log_iovec	*vecp = NULL;
+
+	cudp->cud_format.cud_type = XFS_LI_CUD;
+	cudp->cud_format.cud_size = 1;
+
+	xlog_copy_iovec(lv, &vecp, XLOG_REG_TYPE_CUD_FORMAT, &cudp->cud_format,
+			sizeof(struct xfs_cud_log_format));
+}
+
+/*
+ * The CUD is either committed or aborted if the transaction is cancelled. If
+ * the transaction is cancelled, drop our reference to the CUI and free the
+ * CUD.
+ */
+STATIC void
+xfs_cud_item_release(
+	struct xfs_log_item	*lip)
+{
+	struct xfs_cud_log_item	*cudp = CUD_ITEM(lip);
+
+	xfs_cui_release(cudp->cud_cuip);
+	kmem_free(cudp->cud_item.li_lv_shadow);
+	kmem_cache_free(xfs_cud_cache, cudp);
+}
+
+static struct xfs_log_item *
+xfs_cud_item_intent(
+	struct xfs_log_item	*lip)
+{
+	return &CUD_ITEM(lip)->cud_cuip->cui_item;
+}
+
+static const struct xfs_item_ops xfs_cud_item_ops = {
+	.flags		= XFS_ITEM_RELEASE_WHEN_COMMITTED |
+			  XFS_ITEM_INTENT_DONE,
+	.iop_size	= xfs_cud_item_size,
+	.iop_format	= xfs_cud_item_format,
+	.iop_release	= xfs_cud_item_release,
+	.iop_intent	= xfs_cud_item_intent,
+};
+
+static struct xfs_cud_log_item *
+xfs_trans_get_cud(
+	struct xfs_trans		*tp,
+	struct xfs_cui_log_item		*cuip)
+{
+	struct xfs_cud_log_item		*cudp;
+
+	cudp = kmem_cache_zalloc(xfs_cud_cache, GFP_KERNEL | __GFP_NOFAIL);
+	xfs_log_item_init(tp->t_mountp, &cudp->cud_item, XFS_LI_CUD,
+			  &xfs_cud_item_ops);
+	cudp->cud_cuip = cuip;
+	cudp->cud_format.cud_cui_id = cuip->cui_format.cui_id;
+
+	xfs_trans_add_item(tp, &cudp->cud_item);
+	return cudp;
+}
+
+/*
+ * Finish an refcount update and log it to the CUD. Note that the
+ * transaction is marked dirty regardless of whether the refcount
+ * update succeeds or fails to support the CUI/CUD lifecycle rules.
+ */
+static int
+xfs_trans_log_finish_refcount_update(
+	struct xfs_trans		*tp,
+	struct xfs_cud_log_item		*cudp,
+	enum xfs_refcount_intent_type	type,
+	xfs_fsblock_t			startblock,
+	xfs_extlen_t			blockcount,
+	xfs_fsblock_t			*new_fsb,
+	xfs_extlen_t			*new_len,
+	struct xfs_btree_cur		**pcur)
+{
+	int				error;
+
+	error = xfs_refcount_finish_one(tp, type, startblock,
+			blockcount, new_fsb, new_len, pcur);
+
+	/*
+	 * Mark the transaction dirty, even on error. This ensures the
+	 * transaction is aborted, which:
+	 *
+	 * 1.) releases the CUI and frees the CUD
+	 * 2.) shuts down the filesystem
+	 */
+	tp->t_flags |= XFS_TRANS_DIRTY | XFS_TRANS_HAS_INTENT_DONE;
+	set_bit(XFS_LI_DIRTY, &cudp->cud_item.li_flags);
+
+	return error;
+}
+
+/* Sort refcount intents by AG. */
+static int
+xfs_refcount_update_diff_items(
+	void				*priv,
+	const struct list_head		*a,
+	const struct list_head		*b)
+{
+	struct xfs_mount		*mp = priv;
+	struct xfs_refcount_intent	*ra;
+	struct xfs_refcount_intent	*rb;
+
+	ra = container_of(a, struct xfs_refcount_intent, ri_list);
+	rb = container_of(b, struct xfs_refcount_intent, ri_list);
+	return  XFS_FSB_TO_AGNO(mp, ra->ri_startblock) -
+		XFS_FSB_TO_AGNO(mp, rb->ri_startblock);
+}
+
+/* Set the phys extent flags for this reverse mapping. */
+static void
+xfs_trans_set_refcount_flags(
+	struct xfs_phys_extent		*refc,
+	enum xfs_refcount_intent_type	type)
+{
+	refc->pe_flags = 0;
+	switch (type) {
+	case XFS_REFCOUNT_INCREASE:
+	case XFS_REFCOUNT_DECREASE:
+	case XFS_REFCOUNT_ALLOC_COW:
+	case XFS_REFCOUNT_FREE_COW:
+		refc->pe_flags |= type;
+		break;
+	default:
+		ASSERT(0);
+	}
+}
+
+/* Log refcount updates in the intent item. */
+STATIC void
+xfs_refcount_update_log_item(
+	struct xfs_trans		*tp,
+	struct xfs_cui_log_item		*cuip,
+	struct xfs_refcount_intent	*refc)
+{
+	uint				next_extent;
+	struct xfs_phys_extent		*ext;
+
+	tp->t_flags |= XFS_TRANS_DIRTY;
+	set_bit(XFS_LI_DIRTY, &cuip->cui_item.li_flags);
+
+	/*
+	 * atomic_inc_return gives us the value after the increment;
+	 * we want to use it as an array index so we need to subtract 1 from
+	 * it.
+	 */
+	next_extent = atomic_inc_return(&cuip->cui_next_extent) - 1;
+	ASSERT(next_extent < cuip->cui_format.cui_nextents);
+	ext = &cuip->cui_format.cui_extents[next_extent];
+	ext->pe_startblock = refc->ri_startblock;
+	ext->pe_len = refc->ri_blockcount;
+	xfs_trans_set_refcount_flags(ext, refc->ri_type);
+}
+
+static struct xfs_log_item *
+xfs_refcount_update_create_intent(
+	struct xfs_trans		*tp,
+	struct list_head		*items,
+	unsigned int			count,
+	bool				sort)
+{
+	struct xfs_mount		*mp = tp->t_mountp;
+	struct xfs_cui_log_item		*cuip = xfs_cui_init(mp, count);
+	struct xfs_refcount_intent	*refc;
+
+	ASSERT(count > 0);
+
+	xfs_trans_add_item(tp, &cuip->cui_item);
+	if (sort)
+		list_sort(mp, items, xfs_refcount_update_diff_items);
+	list_for_each_entry(refc, items, ri_list)
+		xfs_refcount_update_log_item(tp, cuip, refc);
+	return &cuip->cui_item;
+}
+
+/* Get an CUD so we can process all the deferred refcount updates. */
+static struct xfs_log_item *
+xfs_refcount_update_create_done(
+	struct xfs_trans		*tp,
+	struct xfs_log_item		*intent,
+	unsigned int			count)
+{
+	return &xfs_trans_get_cud(tp, CUI_ITEM(intent))->cud_item;
+}
+
+/* Process a deferred refcount update. */
+STATIC int
+xfs_refcount_update_finish_item(
+	struct xfs_trans		*tp,
+	struct xfs_log_item		*done,
+	struct list_head		*item,
+	struct xfs_btree_cur		**state)
+{
+	struct xfs_refcount_intent	*refc;
+	xfs_fsblock_t			new_fsb;
+	xfs_extlen_t			new_aglen;
+	int				error;
+
+	refc = container_of(item, struct xfs_refcount_intent, ri_list);
+	error = xfs_trans_log_finish_refcount_update(tp, CUD_ITEM(done),
+			refc->ri_type, refc->ri_startblock, refc->ri_blockcount,
+			&new_fsb, &new_aglen, state);
+
+	/* Did we run out of reservation?  Requeue what we didn't finish. */
+	if (!error && new_aglen > 0) {
+		ASSERT(refc->ri_type == XFS_REFCOUNT_INCREASE ||
+		       refc->ri_type == XFS_REFCOUNT_DECREASE);
+		refc->ri_startblock = new_fsb;
+		refc->ri_blockcount = new_aglen;
+		return -EAGAIN;
+	}
+	kmem_cache_free(xfs_refcount_intent_cache, refc);
+	return error;
+}
+
+/* Abort all pending CUIs. */
+STATIC void
+xfs_refcount_update_abort_intent(
+	struct xfs_log_item		*intent)
+{
+	xfs_cui_release(CUI_ITEM(intent));
+}
+
+/* Cancel a deferred refcount update. */
+STATIC void
+xfs_refcount_update_cancel_item(
+	struct list_head		*item)
+{
+	struct xfs_refcount_intent	*refc;
+
+	refc = container_of(item, struct xfs_refcount_intent, ri_list);
+	kmem_cache_free(xfs_refcount_intent_cache, refc);
+}
+
+const struct xfs_defer_op_type xfs_refcount_update_defer_type = {
+	.max_items	= XFS_CUI_MAX_FAST_EXTENTS,
+	.create_intent	= xfs_refcount_update_create_intent,
+	.abort_intent	= xfs_refcount_update_abort_intent,
+	.create_done	= xfs_refcount_update_create_done,
+	.finish_item	= xfs_refcount_update_finish_item,
+	.finish_cleanup = xfs_refcount_finish_one_cleanup,
+	.cancel_item	= xfs_refcount_update_cancel_item,
+};
+
+/* Is this recovered CUI ok? */
+static inline bool
+xfs_cui_validate_phys(
+	struct xfs_mount		*mp,
+	struct xfs_phys_extent		*refc)
+{
+	if (!xfs_has_reflink(mp))
+		return false;
+
+	if (refc->pe_flags & ~XFS_REFCOUNT_EXTENT_FLAGS)
+		return false;
+
+	switch (refc->pe_flags & XFS_REFCOUNT_EXTENT_TYPE_MASK) {
+	case XFS_REFCOUNT_INCREASE:
+	case XFS_REFCOUNT_DECREASE:
+	case XFS_REFCOUNT_ALLOC_COW:
+	case XFS_REFCOUNT_FREE_COW:
+		break;
+	default:
+		return false;
+	}
+
+	return xfs_verify_fsbext(mp, refc->pe_startblock, refc->pe_len);
+}
+
+/*
+ * Process a refcount update intent item that was recovered from the log.
+ * We need to update the refcountbt.
+ */
+STATIC int
+xfs_cui_item_recover(
+	struct xfs_log_item		*lip,
+	struct list_head		*capture_list)
+{
+	struct xfs_bmbt_irec		irec;
+	struct xfs_cui_log_item		*cuip = CUI_ITEM(lip);
+	struct xfs_phys_extent		*refc;
+	struct xfs_cud_log_item		*cudp;
+	struct xfs_trans		*tp;
+	struct xfs_btree_cur		*rcur = NULL;
+	struct xfs_mount		*mp = lip->li_log->l_mp;
+	xfs_fsblock_t			new_fsb;
+	xfs_extlen_t			new_len;
+	unsigned int			refc_type;
+	bool				requeue_only = false;
+	enum xfs_refcount_intent_type	type;
+	int				i;
+	int				error = 0;
+
+	/*
+	 * First check the validity of the extents described by the
+	 * CUI.  If any are bad, then assume that all are bad and
+	 * just toss the CUI.
+	 */
+	for (i = 0; i < cuip->cui_format.cui_nextents; i++) {
+		if (!xfs_cui_validate_phys(mp,
+					&cuip->cui_format.cui_extents[i])) {
+			XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
+					&cuip->cui_format,
+					sizeof(cuip->cui_format));
+			return -EFSCORRUPTED;
+		}
+	}
+
+	/*
+	 * Under normal operation, refcount updates are deferred, so we
+	 * wouldn't be adding them directly to a transaction.  All
+	 * refcount updates manage reservation usage internally and
+	 * dynamically by deferring work that won't fit in the
+	 * transaction.  Normally, any work that needs to be deferred
+	 * gets attached to the same defer_ops that scheduled the
+	 * refcount update.  However, we're in log recovery here, so we
+	 * use the passed in defer_ops and to finish up any work that
+	 * doesn't fit.  We need to reserve enough blocks to handle a
+	 * full btree split on either end of the refcount range.
+	 */
+	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate,
+			mp->m_refc_maxlevels * 2, 0, XFS_TRANS_RESERVE, &tp);
+	if (error)
+		return error;
+
+	cudp = xfs_trans_get_cud(tp, cuip);
+
+	for (i = 0; i < cuip->cui_format.cui_nextents; i++) {
+		refc = &cuip->cui_format.cui_extents[i];
+		refc_type = refc->pe_flags & XFS_REFCOUNT_EXTENT_TYPE_MASK;
+		switch (refc_type) {
+		case XFS_REFCOUNT_INCREASE:
+		case XFS_REFCOUNT_DECREASE:
+		case XFS_REFCOUNT_ALLOC_COW:
+		case XFS_REFCOUNT_FREE_COW:
+			type = refc_type;
+			break;
+		default:
+			XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
+					&cuip->cui_format,
+					sizeof(cuip->cui_format));
+			error = -EFSCORRUPTED;
+			goto abort_error;
+		}
+		if (requeue_only) {
+			new_fsb = refc->pe_startblock;
+			new_len = refc->pe_len;
+		} else
+			error = xfs_trans_log_finish_refcount_update(tp, cudp,
+				type, refc->pe_startblock, refc->pe_len,
+				&new_fsb, &new_len, &rcur);
+		if (error == -EFSCORRUPTED)
+			XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
+					&cuip->cui_format,
+					sizeof(cuip->cui_format));
+		if (error)
+			goto abort_error;
+
+		/* Requeue what we didn't finish. */
+		if (new_len > 0) {
+			irec.br_startblock = new_fsb;
+			irec.br_blockcount = new_len;
+			switch (type) {
+			case XFS_REFCOUNT_INCREASE:
+				xfs_refcount_increase_extent(tp, &irec);
+				break;
+			case XFS_REFCOUNT_DECREASE:
+				xfs_refcount_decrease_extent(tp, &irec);
+				break;
+			case XFS_REFCOUNT_ALLOC_COW:
+				xfs_refcount_alloc_cow_extent(tp,
+						irec.br_startblock,
+						irec.br_blockcount);
+				break;
+			case XFS_REFCOUNT_FREE_COW:
+				xfs_refcount_free_cow_extent(tp,
+						irec.br_startblock,
+						irec.br_blockcount);
+				break;
+			default:
+				ASSERT(0);
+			}
+			requeue_only = true;
+		}
+	}
+
+	xfs_refcount_finish_one_cleanup(tp, rcur, error);
+	return xfs_defer_ops_capture_and_commit(tp, capture_list);
+
+abort_error:
+	xfs_refcount_finish_one_cleanup(tp, rcur, error);
+	xfs_trans_cancel(tp);
+	return error;
+}
+
+STATIC bool
+xfs_cui_item_match(
+	struct xfs_log_item	*lip,
+	uint64_t		intent_id)
+{
+	return CUI_ITEM(lip)->cui_format.cui_id == intent_id;
+}
+
+/* Relog an intent item to push the log tail forward. */
+static struct xfs_log_item *
+xfs_cui_item_relog(
+	struct xfs_log_item		*intent,
+	struct xfs_trans		*tp)
+{
+	struct xfs_cud_log_item		*cudp;
+	struct xfs_cui_log_item		*cuip;
+	struct xfs_phys_extent		*extp;
+	unsigned int			count;
+
+	count = CUI_ITEM(intent)->cui_format.cui_nextents;
+	extp = CUI_ITEM(intent)->cui_format.cui_extents;
+
+	tp->t_flags |= XFS_TRANS_DIRTY;
+	cudp = xfs_trans_get_cud(tp, CUI_ITEM(intent));
+	set_bit(XFS_LI_DIRTY, &cudp->cud_item.li_flags);
+
+	cuip = xfs_cui_init(tp->t_mountp, count);
+	memcpy(cuip->cui_format.cui_extents, extp, count * sizeof(*extp));
+	atomic_set(&cuip->cui_next_extent, count);
+	xfs_trans_add_item(tp, &cuip->cui_item);
+	set_bit(XFS_LI_DIRTY, &cuip->cui_item.li_flags);
+	return &cuip->cui_item;
+}
+
+static const struct xfs_item_ops xfs_cui_item_ops = {
+	.flags		= XFS_ITEM_INTENT,
+	.iop_size	= xfs_cui_item_size,
+	.iop_format	= xfs_cui_item_format,
+	.iop_unpin	= xfs_cui_item_unpin,
+	.iop_release	= xfs_cui_item_release,
+	.iop_recover	= xfs_cui_item_recover,
+	.iop_match	= xfs_cui_item_match,
+	.iop_relog	= xfs_cui_item_relog,
+};
+
+static inline void
+xfs_cui_copy_format(
+	struct xfs_cui_log_format	*dst,
+	const struct xfs_cui_log_format	*src)
+{
+	unsigned int			i;
+
+	memcpy(dst, src, offsetof(struct xfs_cui_log_format, cui_extents));
+
+	for (i = 0; i < src->cui_nextents; i++)
+		memcpy(&dst->cui_extents[i], &src->cui_extents[i],
+				sizeof(struct xfs_phys_extent));
+}
+
+/*
+ * This routine is called to create an in-core extent refcount update
+ * item from the cui format structure which was logged on disk.
+ * It allocates an in-core cui, copies the extents from the format
+ * structure into it, and adds the cui to the AIL with the given
+ * LSN.
+ */
+STATIC int
+xlog_recover_cui_commit_pass2(
+	struct xlog			*log,
+	struct list_head		*buffer_list,
+	struct xlog_recover_item	*item,
+	xfs_lsn_t			lsn)
+{
+	struct xfs_mount		*mp = log->l_mp;
+	struct xfs_cui_log_item		*cuip;
+	struct xfs_cui_log_format	*cui_formatp;
+	size_t				len;
+
+	cui_formatp = item->ri_buf[0].i_addr;
+
+	if (item->ri_buf[0].i_len < xfs_cui_log_format_sizeof(0)) {
+		XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
+				item->ri_buf[0].i_addr, item->ri_buf[0].i_len);
+		return -EFSCORRUPTED;
+	}
+
+	len = xfs_cui_log_format_sizeof(cui_formatp->cui_nextents);
+	if (item->ri_buf[0].i_len != len) {
+		XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, mp,
+				item->ri_buf[0].i_addr, item->ri_buf[0].i_len);
+		return -EFSCORRUPTED;
+	}
+
+	cuip = xfs_cui_init(mp, cui_formatp->cui_nextents);
+	xfs_cui_copy_format(&cuip->cui_format, cui_formatp);
+	atomic_set(&cuip->cui_next_extent, cui_formatp->cui_nextents);
+	/*
+	 * Insert the intent into the AIL directly and drop one reference so
+	 * that finishing or canceling the work will drop the other.
+	 */
+	xfs_trans_ail_insert(log->l_ailp, &cuip->cui_item, lsn);
+	xfs_cui_release(cuip);
+	return 0;
+}
+
+const struct xlog_recover_item_ops xlog_cui_item_ops = {
+	.item_type		= XFS_LI_CUI,
+	.commit_pass2		= xlog_recover_cui_commit_pass2,
+};
+
+/*
+ * This routine is called when an CUD format structure is found in a committed
+ * transaction in the log. Its purpose is to cancel the corresponding CUI if it
+ * was still in the log. To do this it searches the AIL for the CUI with an id
+ * equal to that in the CUD format structure. If we find it we drop the CUD
+ * reference, which removes the CUI from the AIL and frees it.
+ */
+STATIC int
+xlog_recover_cud_commit_pass2(
+	struct xlog			*log,
+	struct list_head		*buffer_list,
+	struct xlog_recover_item	*item,
+	xfs_lsn_t			lsn)
+{
+	struct xfs_cud_log_format	*cud_formatp;
+
+	cud_formatp = item->ri_buf[0].i_addr;
+	if (item->ri_buf[0].i_len != sizeof(struct xfs_cud_log_format)) {
+		XFS_CORRUPTION_ERROR(__func__, XFS_ERRLEVEL_LOW, log->l_mp,
+				item->ri_buf[0].i_addr, item->ri_buf[0].i_len);
+		return -EFSCORRUPTED;
+	}
+
+	xlog_recover_release_intent(log, XFS_LI_CUI, cud_formatp->cud_cui_id);
+	return 0;
+}
+
+const struct xlog_recover_item_ops xlog_cud_item_ops = {
+	.item_type		= XFS_LI_CUD,
+	.commit_pass2		= xlog_recover_cud_commit_pass2,
+};