diff mbox

[064/119] xfs: connect refcount adjust functions to upper layers

Message ID 146612668240.12839.9385528375591866350.stgit@birch.djwong.org (mailing list archive)
State New, archived
Headers show

Commit Message

Darrick J. Wong June 17, 2016, 1:24 a.m. UTC
Plumb in the upper level interface to schedule and finish deferred
refcount operations via the deferred ops mechanism.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/libxfs/xfs_defer.h    |    1 
 fs/xfs/libxfs/xfs_refcount.c |  171 ++++++++++++++++++++++++++++++++++++++++++
 fs/xfs/libxfs/xfs_refcount.h |   12 +++
 fs/xfs/xfs_defer_item.c      |  132 ++++++++++++++++++++++++++++++++
 fs/xfs/xfs_error.h           |    4 +
 fs/xfs/xfs_log_recover.c     |   79 +++++++++++++++++++
 fs/xfs/xfs_trace.h           |    3 +
 fs/xfs/xfs_trans.h           |    6 +
 fs/xfs/xfs_trans_refcount.c  |   10 ++
 9 files changed, 411 insertions(+), 7 deletions(-)



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diff mbox

Patch

diff --git a/fs/xfs/libxfs/xfs_defer.h b/fs/xfs/libxfs/xfs_defer.h
index 920642e62..4081b00 100644
--- a/fs/xfs/libxfs/xfs_defer.h
+++ b/fs/xfs/libxfs/xfs_defer.h
@@ -51,6 +51,7 @@  struct xfs_defer_pending {
  * find all the space it needs.
  */
 enum xfs_defer_ops_type {
+	XFS_DEFER_OPS_TYPE_REFCOUNT,
 	XFS_DEFER_OPS_TYPE_RMAP,
 	XFS_DEFER_OPS_TYPE_FREE,
 	XFS_DEFER_OPS_TYPE_MAX,
diff --git a/fs/xfs/libxfs/xfs_refcount.c b/fs/xfs/libxfs/xfs_refcount.c
index d13393b..bfbdbad 100644
--- a/fs/xfs/libxfs/xfs_refcount.c
+++ b/fs/xfs/libxfs/xfs_refcount.c
@@ -958,3 +958,174 @@  out_error:
 			error, _RET_IP_);
 	return error;
 }
+
+/* Clean up after calling xfs_refcount_finish_one. */
+void
+xfs_refcount_finish_one_cleanup(
+	struct xfs_trans	*tp,
+	struct xfs_btree_cur	*rcur,
+	int			error)
+{
+	struct xfs_buf		*agbp;
+
+	if (rcur == NULL)
+		return;
+	agbp = rcur->bc_private.a.agbp;
+	xfs_btree_del_cursor(rcur, error ? XFS_BTREE_ERROR : XFS_BTREE_NOERROR);
+	xfs_trans_brelse(tp, agbp);
+}
+
+/*
+ * Process one of the deferred refcount operations.  We pass back the
+ * btree cursor to maintain our lock on the btree between calls.
+ * This saves time and eliminates a buffer deadlock between the
+ * superblock and the AGF because we'll always grab them in the same
+ * order.
+ */
+int
+xfs_refcount_finish_one(
+	struct xfs_trans		*tp,
+	struct xfs_defer_ops		*dfops,
+	enum xfs_refcount_intent_type	type,
+	xfs_fsblock_t			startblock,
+	xfs_extlen_t			blockcount,
+	xfs_extlen_t			*adjusted,
+	struct xfs_btree_cur		**pcur)
+{
+	struct xfs_mount		*mp = tp->t_mountp;
+	struct xfs_btree_cur		*rcur;
+	struct xfs_buf			*agbp = NULL;
+	int				error = 0;
+	xfs_agnumber_t			agno;
+	xfs_agblock_t			bno;
+	unsigned long			nr_ops = 0;
+	int				shape_changes = 0;
+
+	agno = XFS_FSB_TO_AGNO(mp, startblock);
+	ASSERT(agno != NULLAGNUMBER);
+	bno = XFS_FSB_TO_AGBNO(mp, startblock);
+
+	trace_xfs_refcount_deferred(mp, XFS_FSB_TO_AGNO(mp, startblock),
+			type, XFS_FSB_TO_AGBNO(mp, startblock),
+			blockcount);
+
+	if (XFS_TEST_ERROR(false, mp,
+			XFS_ERRTAG_REFCOUNT_FINISH_ONE,
+			XFS_RANDOM_REFCOUNT_FINISH_ONE))
+		return -EIO;
+
+	/*
+	 * If we haven't gotten a cursor or the cursor AG doesn't match
+	 * the startblock, get one now.
+	 */
+	rcur = *pcur;
+	if (rcur != NULL && rcur->bc_private.a.agno != agno) {
+		nr_ops = rcur->bc_private.a.priv.refc.nr_ops;
+		shape_changes = rcur->bc_private.a.priv.refc.shape_changes;
+		xfs_refcount_finish_one_cleanup(tp, rcur, 0);
+		rcur = NULL;
+		*pcur = NULL;
+	}
+	if (rcur == NULL) {
+		error = xfs_alloc_read_agf(tp->t_mountp, tp, agno,
+				XFS_ALLOC_FLAG_FREEING, &agbp);
+		if (error)
+			return error;
+		if (!agbp)
+			return -EFSCORRUPTED;
+
+		rcur = xfs_refcountbt_init_cursor(mp, tp, agbp, agno, dfops);
+		if (!rcur) {
+			error = -ENOMEM;
+			goto out_cur;
+		}
+		rcur->bc_private.a.priv.refc.nr_ops = nr_ops;
+		rcur->bc_private.a.priv.refc.shape_changes = shape_changes;
+	}
+	*pcur = rcur;
+
+	switch (type) {
+	case XFS_REFCOUNT_INCREASE:
+		error = xfs_refcount_adjust(rcur, bno, blockcount, adjusted,
+			XFS_REFCOUNT_ADJUST_INCREASE, dfops, NULL);
+		break;
+	case XFS_REFCOUNT_DECREASE:
+		error = xfs_refcount_adjust(rcur, bno, blockcount, adjusted,
+			XFS_REFCOUNT_ADJUST_DECREASE, dfops, NULL);
+		break;
+	default:
+		ASSERT(0);
+		error = -EFSCORRUPTED;
+	}
+	if (!error && *adjusted != blockcount)
+		trace_xfs_refcount_finish_one_leftover(mp, agno, type,
+				bno, blockcount, *adjusted);
+	return error;
+
+out_cur:
+	xfs_trans_brelse(tp, agbp);
+
+	return error;
+}
+
+/*
+ * Record a refcount intent for later processing.
+ */
+static int
+__xfs_refcount_add(
+	struct xfs_mount		*mp,
+	struct xfs_defer_ops		*dfops,
+	struct xfs_refcount_intent	*ri)
+{
+	struct xfs_refcount_intent	*new;
+
+	if (!xfs_sb_version_hasreflink(&mp->m_sb))
+		return 0;
+
+	trace_xfs_refcount_defer(mp, XFS_FSB_TO_AGNO(mp, ri->ri_startblock),
+			ri->ri_type, XFS_FSB_TO_AGBNO(mp, ri->ri_startblock),
+			ri->ri_blockcount);
+
+	new = kmem_zalloc(sizeof(struct xfs_refcount_intent),
+			KM_SLEEP | KM_NOFS);
+	*new = *ri;
+
+	xfs_defer_add(dfops, XFS_DEFER_OPS_TYPE_REFCOUNT, &new->ri_list);
+	return 0;
+}
+
+/*
+ * Increase the reference count of the blocks backing a file's extent.
+ */
+int
+xfs_refcount_increase_extent(
+	struct xfs_mount		*mp,
+	struct xfs_defer_ops		*dfops,
+	struct xfs_bmbt_irec		*PREV)
+{
+	struct xfs_refcount_intent	ri;
+
+	ri.ri_type = XFS_REFCOUNT_INCREASE;
+	ri.ri_startblock = PREV->br_startblock;
+	ri.ri_blockcount = PREV->br_blockcount;
+
+	return __xfs_refcount_add(mp, dfops, &ri);
+}
+
+/*
+ * Decrease the reference count of the blocks backing a file's extent.
+ */
+int
+xfs_refcount_decrease_extent(
+	struct xfs_mount		*mp,
+	struct xfs_defer_ops		*dfops,
+	struct xfs_bmbt_irec		*PREV)
+{
+	struct xfs_refcount_intent	ri;
+
+	ri.ri_type = XFS_REFCOUNT_DECREASE;
+	ri.ri_startblock = PREV->br_startblock;
+	ri.ri_blockcount = PREV->br_blockcount;
+
+	return __xfs_refcount_add(mp, dfops, &ri);
+}
diff --git a/fs/xfs/libxfs/xfs_refcount.h b/fs/xfs/libxfs/xfs_refcount.h
index 0b36c1d..92c05ea 100644
--- a/fs/xfs/libxfs/xfs_refcount.h
+++ b/fs/xfs/libxfs/xfs_refcount.h
@@ -41,4 +41,16 @@  struct xfs_refcount_intent {
 	xfs_extlen_t				ri_blockcount;
 };
 
+extern int xfs_refcount_increase_extent(struct xfs_mount *mp,
+		struct xfs_defer_ops *dfops, struct xfs_bmbt_irec *irec);
+extern int xfs_refcount_decrease_extent(struct xfs_mount *mp,
+		struct xfs_defer_ops *dfops, struct xfs_bmbt_irec *irec);
+
+extern void xfs_refcount_finish_one_cleanup(struct xfs_trans *tp,
+		struct xfs_btree_cur *rcur, int error);
+extern int xfs_refcount_finish_one(struct xfs_trans *tp,
+		struct xfs_defer_ops *dfops, enum xfs_refcount_intent_type type,
+		xfs_fsblock_t startblock, xfs_extlen_t blockcount,
+		xfs_extlen_t *adjusted, struct xfs_btree_cur **pcur);
+
 #endif	/* __XFS_REFCOUNT_H__ */
diff --git a/fs/xfs/xfs_defer_item.c b/fs/xfs/xfs_defer_item.c
index 9ed060d..2cac94f 100644
--- a/fs/xfs/xfs_defer_item.c
+++ b/fs/xfs/xfs_defer_item.c
@@ -33,6 +33,8 @@ 
 #include "xfs_extfree_item.h"
 #include "xfs_rmap_btree.h"
 #include "xfs_rmap_item.h"
+#include "xfs_refcount.h"
+#include "xfs_refcount_item.h"
 
 /* Extent Freeing */
 
@@ -263,12 +265,142 @@  const struct xfs_defer_op_type xfs_rmap_update_defer_type = {
 	.cancel_item	= xfs_rmap_update_cancel_item,
 };
 
+/* Reference Counting */
+
+/* Sort rmap intents by AG. */
+static int
+xfs_refcount_update_diff_items(
+	void				*priv,
+	struct list_head		*a,
+	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);
+}
+
+/* Get an CUI. */
+STATIC void *
+xfs_refcount_update_create_intent(
+	struct xfs_trans		*tp,
+	unsigned int			count)
+{
+	return xfs_trans_get_cui(tp, count);
+}
+
+/* Log refcount updates in the intent item. */
+STATIC void
+xfs_refcount_update_log_item(
+	struct xfs_trans		*tp,
+	void				*intent,
+	struct list_head		*item)
+{
+	struct xfs_refcount_intent	*refc;
+
+	refc = container_of(item, struct xfs_refcount_intent, ri_list);
+	xfs_trans_log_start_refcount_update(tp, intent, refc->ri_type,
+			refc->ri_startblock,
+			refc->ri_blockcount);
+}
+
+/* Get an CUD so we can process all the deferred refcount updates. */
+STATIC void *
+xfs_refcount_update_create_done(
+	struct xfs_trans		*tp,
+	void				*intent,
+	unsigned int			count)
+{
+	return xfs_trans_get_cud(tp, intent, count);
+}
+
+/* Process a deferred refcount update. */
+STATIC int
+xfs_refcount_update_finish_item(
+	struct xfs_trans		*tp,
+	struct xfs_defer_ops		*dop,
+	struct list_head		*item,
+	void				*done_item,
+	void				**state)
+{
+	struct xfs_refcount_intent	*refc;
+	xfs_extlen_t			adjusted;
+	int				error;
+
+	refc = container_of(item, struct xfs_refcount_intent, ri_list);
+	error = xfs_trans_log_finish_refcount_update(tp, done_item, dop,
+			refc->ri_type,
+			refc->ri_startblock,
+			refc->ri_blockcount,
+			&adjusted,
+			(struct xfs_btree_cur **)state);
+	/* Did we run out of reservation?  Requeue what we didn't finish. */
+	if (!error && adjusted < refc->ri_blockcount) {
+		ASSERT(refc->ri_type == XFS_REFCOUNT_INCREASE ||
+		       refc->ri_type == XFS_REFCOUNT_DECREASE);
+		refc->ri_startblock += adjusted;
+		refc->ri_blockcount -= adjusted;
+		return -EAGAIN;
+	}
+	kmem_free(refc);
+	return error;
+}
+
+/* Clean up after processing deferred refcounts. */
+STATIC void
+xfs_refcount_update_finish_cleanup(
+	struct xfs_trans	*tp,
+	void			*state,
+	int			error)
+{
+	struct xfs_btree_cur	*rcur = state;
+
+	xfs_refcount_finish_one_cleanup(tp, rcur, error);
+}
+
+/* Abort all pending CUIs. */
+STATIC void
+xfs_refcount_update_abort_intent(
+	void				*intent)
+{
+	xfs_cui_release(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_free(refc);
+}
+
+const struct xfs_defer_op_type xfs_refcount_update_defer_type = {
+	.type		= XFS_DEFER_OPS_TYPE_REFCOUNT,
+	.max_items	= XFS_CUI_MAX_FAST_EXTENTS,
+	.diff_items	= xfs_refcount_update_diff_items,
+	.create_intent	= xfs_refcount_update_create_intent,
+	.abort_intent	= xfs_refcount_update_abort_intent,
+	.log_item	= xfs_refcount_update_log_item,
+	.create_done	= xfs_refcount_update_create_done,
+	.finish_item	= xfs_refcount_update_finish_item,
+	.finish_cleanup = xfs_refcount_update_finish_cleanup,
+	.cancel_item	= xfs_refcount_update_cancel_item,
+};
+
 /* Deferred Item Initialization */
 
 /* Initialize the deferred operation types. */
 void
 xfs_defer_init_types(void)
 {
+	xfs_defer_init_op_type(&xfs_refcount_update_defer_type);
 	xfs_defer_init_op_type(&xfs_rmap_update_defer_type);
 	xfs_defer_init_op_type(&xfs_extent_free_defer_type);
 }
diff --git a/fs/xfs/xfs_error.h b/fs/xfs/xfs_error.h
index ffeffb5..83d7b62 100644
--- a/fs/xfs/xfs_error.h
+++ b/fs/xfs/xfs_error.h
@@ -93,7 +93,8 @@  extern void xfs_verifier_error(struct xfs_buf *bp);
 #define XFS_ERRTAG_FREE_EXTENT				22
 #define XFS_ERRTAG_RMAP_FINISH_ONE			23
 #define XFS_ERRTAG_REFCOUNT_CONTINUE_UPDATE		24
-#define XFS_ERRTAG_MAX					25
+#define XFS_ERRTAG_REFCOUNT_FINISH_ONE			25
+#define XFS_ERRTAG_MAX					26
 
 /*
  * Random factors for above tags, 1 means always, 2 means 1/2 time, etc.
@@ -123,6 +124,7 @@  extern void xfs_verifier_error(struct xfs_buf *bp);
 #define XFS_RANDOM_FREE_EXTENT				1
 #define XFS_RANDOM_RMAP_FINISH_ONE			1
 #define XFS_RANDOM_REFCOUNT_CONTINUE_UPDATE		1
+#define XFS_RANDOM_REFCOUNT_FINISH_ONE			1
 
 #ifdef DEBUG
 extern int xfs_error_test_active;
diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c
index e0a470a..ee37dc5 100644
--- a/fs/xfs/xfs_log_recover.c
+++ b/fs/xfs/xfs_log_recover.c
@@ -47,6 +47,7 @@ 
 #include "xfs_rmap_item.h"
 #include "xfs_rmap_btree.h"
 #include "xfs_refcount_item.h"
+#include "xfs_refcount.h"
 
 #define BLK_AVG(blk1, blk2)	((blk1+blk2) >> 1)
 
@@ -4833,6 +4834,15 @@  xlog_recover_process_cui(
 	struct xfs_phys_extent		*refc;
 	xfs_fsblock_t			startblock_fsb;
 	bool				op_ok;
+	struct xfs_cud_log_item		*cudp;
+	struct xfs_trans		*tp;
+	struct xfs_btree_cur		*rcur = NULL;
+	enum xfs_refcount_intent_type	type;
+	xfs_fsblock_t			firstfsb;
+	xfs_extlen_t			adjusted;
+	struct xfs_bmbt_irec		irec;
+	struct xfs_defer_ops		dfops;
+	bool				requeue_only = false;
 
 	ASSERT(!test_bit(XFS_CUI_RECOVERED, &cuip->cui_flags));
 
@@ -4871,9 +4881,74 @@  xlog_recover_process_cui(
 		}
 	}
 
-	/* XXX: do nothing for now */
+	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0, &tp);
+	if (error)
+		return error;
+	cudp = xfs_trans_get_cud(tp, cuip, cuip->cui_format.cui_nextents);
+
+	xfs_defer_init(&dfops, &firstfsb);
+	for (i = 0; i < cuip->cui_format.cui_nextents; i++) {
+		refc = &(cuip->cui_format.cui_extents[i]);
+		switch (refc->pe_flags & XFS_REFCOUNT_EXTENT_TYPE_MASK) {
+		case XFS_REFCOUNT_EXTENT_INCREASE:
+			type = XFS_REFCOUNT_INCREASE;
+			break;
+		case XFS_REFCOUNT_EXTENT_DECREASE:
+			type = XFS_REFCOUNT_DECREASE;
+			break;
+		case XFS_REFCOUNT_EXTENT_ALLOC_COW:
+			type = XFS_REFCOUNT_ALLOC_COW;
+			break;
+		case XFS_REFCOUNT_EXTENT_FREE_COW:
+			type = XFS_REFCOUNT_FREE_COW;
+			break;
+		default:
+			error = -EFSCORRUPTED;
+			goto abort_error;
+		}
+		if (requeue_only)
+			adjusted = 0;
+		else
+			error = xfs_trans_log_finish_refcount_update(tp, cudp,
+				&dfops, type, refc->pe_startblock, refc->pe_len,
+				&adjusted, &rcur);
+		if (error)
+			goto abort_error;
+
+		/* Requeue what we didn't finish. */
+		if (adjusted < refc->pe_len) {
+			irec.br_startblock = refc->pe_startblock + adjusted;
+			irec.br_blockcount = refc->pe_len - adjusted;
+			switch (type) {
+			case XFS_REFCOUNT_INCREASE:
+				error = xfs_refcount_increase_extent(
+						tp->t_mountp, &dfops, &irec);
+				break;
+			case XFS_REFCOUNT_DECREASE:
+				error = xfs_refcount_decrease_extent(
+						tp->t_mountp, &dfops, &irec);
+				break;
+			default:
+				ASSERT(0);
+			}
+			if (error)
+				goto abort_error;
+			requeue_only = true;
+		}
+	}
+
+	xfs_refcount_finish_one_cleanup(tp, rcur, error);
+	error = xfs_defer_finish(&tp, &dfops, NULL);
+	if (error)
+		goto abort_error;
 	set_bit(XFS_CUI_RECOVERED, &cuip->cui_flags);
-	xfs_cui_release(cuip);
+	error = xfs_trans_commit(tp);
+	return error;
+
+abort_error:
+	xfs_refcount_finish_one_cleanup(tp, rcur, error);
+	xfs_defer_cancel(&dfops);
+	xfs_trans_cancel(tp);
 	return error;
 }
 
diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h
index 1f6cee0..8366102 100644
--- a/fs/xfs/xfs_trace.h
+++ b/fs/xfs/xfs_trace.h
@@ -2905,6 +2905,9 @@  DEFINE_REFCOUNT_DOUBLE_EXTENT_EVENT(xfs_refcount_rec_order_error);
 DEFINE_AG_EXTENT_EVENT(xfs_refcount_find_shared);
 DEFINE_AG_EXTENT_EVENT(xfs_refcount_find_shared_result);
 DEFINE_AG_ERROR_EVENT(xfs_refcount_find_shared_error);
+#define DEFINE_REFCOUNT_DEFERRED_EVENT DEFINE_PHYS_EXTENT_DEFERRED_EVENT
+DEFINE_REFCOUNT_DEFERRED_EVENT(xfs_refcount_defer);
+DEFINE_REFCOUNT_DEFERRED_EVENT(xfs_refcount_deferred);
 
 TRACE_EVENT(xfs_refcount_finish_one_leftover,
 	TP_PROTO(struct xfs_mount *mp, xfs_agnumber_t agno,
diff --git a/fs/xfs/xfs_trans.h b/fs/xfs/xfs_trans.h
index 2b197fd..6b6cb4a 100644
--- a/fs/xfs/xfs_trans.h
+++ b/fs/xfs/xfs_trans.h
@@ -33,6 +33,7 @@  struct xfs_trans;
 struct xfs_trans_res;
 struct xfs_dquot_acct;
 struct xfs_busy_extent;
+struct xfs_defer_ops;
 
 typedef struct xfs_log_item {
 	struct list_head		li_ail;		/* AIL pointers */
@@ -264,8 +265,9 @@  void xfs_trans_log_start_refcount_update(struct xfs_trans *tp,
 struct xfs_cud_log_item *xfs_trans_get_cud(struct xfs_trans *tp,
 		struct xfs_cui_log_item *cuip, uint nextents);
 int xfs_trans_log_finish_refcount_update(struct xfs_trans *tp,
-		struct xfs_cud_log_item *cudp,
+		struct xfs_cud_log_item *cudp, struct xfs_defer_ops *dfops,
 		enum xfs_refcount_intent_type type, xfs_fsblock_t startblock,
-		xfs_extlen_t blockcount, struct xfs_btree_cur **pcur);
+		xfs_extlen_t blockcount, xfs_extlen_t *adjusted,
+		struct xfs_btree_cur **pcur);
 
 #endif	/* __XFS_TRANS_H__ */
diff --git a/fs/xfs/xfs_trans_refcount.c b/fs/xfs/xfs_trans_refcount.c
index 32701e4..de30c5a 100644
--- a/fs/xfs/xfs_trans_refcount.c
+++ b/fs/xfs/xfs_trans_refcount.c
@@ -142,17 +142,19 @@  int
 xfs_trans_log_finish_refcount_update(
 	struct xfs_trans		*tp,
 	struct xfs_cud_log_item		*cudp,
+	struct xfs_defer_ops		*dop,
 	enum xfs_refcount_intent_type	type,
 	xfs_fsblock_t			startblock,
 	xfs_extlen_t			blockcount,
+	xfs_extlen_t			*adjusted,
 	struct xfs_btree_cur		**pcur)
 {
 	uint				next_extent;
 	struct xfs_phys_extent		*refc;
 	int				error;
 
-	/* XXX: leave this empty for now */
-	error = -EFSCORRUPTED;
+	error = xfs_refcount_finish_one(tp, dop, type, startblock,
+			blockcount, adjusted, pcur);
 
 	/*
 	 * Mark the transaction dirty, even on error. This ensures the
@@ -187,6 +189,10 @@  xfs_trans_log_finish_refcount_update(
 		ASSERT(0);
 	}
 	cudp->cud_next_extent++;
+	if (!error && *adjusted != blockcount) {
+		refc->pe_len = *adjusted;
+		cudp->cud_format.cud_nextents = cudp->cud_next_extent;
+	}
 
 	return error;
 }