Merge branch 'for-linus' of git://oss.sgi.com/xfs/xfs

* 'for-linus' of git://oss.sgi.com/xfs/xfs:
  xfs: correctly decrement the extent buffer index in xfs_bmap_del_extent
  xfs: check for valid indices in xfs_iext_get_ext and xfs_iext_idx_to_irec
  xfs: fix up asserts in xfs_iflush_fork
  xfs: do not do pointer arithmetic on extent records
  xfs: do not use unchecked extent indices in xfs_bunmapi
  xfs: do not use unchecked extent indices in xfs_bmapi
  xfs: do not use unchecked extent indices in xfs_bmap_add_extent_*
  xfs: remove if_lastex
  xfs: remove the unused XFS_BMAPI_RSVBLOCKS flag
  xfs: do not discard alloc btree blocks
  xfs: add online discard support

15 files changed, 366 insertions, 318 deletions

diff --git a/Documentation/filesystems/xfs.txt b/Documentation/filesystems/xfs.txt
index 7bff3e4f35df..3fc0c31a6f5d 100644
--- a/Documentation/filesystems/xfs.txt
+++ b/Documentation/filesystems/xfs.txt
@@ -39,6 +39,12 @@ When mounting an XFS filesystem, the following options are accepted.
 	drive level write caching to be enabled, for devices that
 	support write barriers.
 
+  discard
+	Issue command to let the block device reclaim space freed by the
+	filesystem.  This is useful for SSD devices, thinly provisioned
+	LUNs and virtual machine images, but may have a performance
+	impact.  This option is incompatible with the nodelaylog option.
+
   dmapi
 	Enable the DMAPI (Data Management API) event callouts.
 	Use with the "mtpt" option.
diff --git a/fs/xfs/linux-2.6/xfs_discard.c b/fs/xfs/linux-2.6/xfs_discard.c
index d61611c88012..244e797dae32 100644
--- a/fs/xfs/linux-2.6/xfs_discard.c
+++ b/fs/xfs/linux-2.6/xfs_discard.c
@@ -191,3 +191,32 @@ xfs_ioc_trim(
 		return -XFS_ERROR(EFAULT);
 	return 0;
 }
+
+int
+xfs_discard_extents(
+	struct xfs_mount	*mp,
+	struct list_head	*list)
+{
+	struct xfs_busy_extent	*busyp;
+	int			error = 0;
+
+	list_for_each_entry(busyp, list, list) {
+		trace_xfs_discard_extent(mp, busyp->agno, busyp->bno,
+					 busyp->length);
+
+		error = -blkdev_issue_discard(mp->m_ddev_targp->bt_bdev,
+				XFS_AGB_TO_DADDR(mp, busyp->agno, busyp->bno),
+				XFS_FSB_TO_BB(mp, busyp->length),
+				GFP_NOFS, 0);
+		if (error && error != EOPNOTSUPP) {
+			xfs_info(mp,
+	 "discard failed for extent [0x%llu,%u], error %d",
+				 (unsigned long long)busyp->bno,
+				 busyp->length,
+				 error);
+			return error;
+		}
+	}
+
+	return 0;
+}
diff --git a/fs/xfs/linux-2.6/xfs_discard.h b/fs/xfs/linux-2.6/xfs_discard.h
index e82b6dd3e127..344879aea646 100644
--- a/fs/xfs/linux-2.6/xfs_discard.h
+++ b/fs/xfs/linux-2.6/xfs_discard.h
@@ -2,7 +2,9 @@
 #define XFS_DISCARD_H 1
 
 struct fstrim_range;
+struct list_head;
 
 extern int	xfs_ioc_trim(struct xfs_mount *, struct fstrim_range __user *);
+extern int	xfs_discard_extents(struct xfs_mount *, struct list_head *);
 
 #endif /* XFS_DISCARD_H */
diff --git a/fs/xfs/linux-2.6/xfs_super.c b/fs/xfs/linux-2.6/xfs_super.c
index b0aa59e51fd0..98b9c91fcdf1 100644
--- a/fs/xfs/linux-2.6/xfs_super.c
+++ b/fs/xfs/linux-2.6/xfs_super.c
@@ -110,8 +110,10 @@ mempool_t *xfs_ioend_pool;
 #define MNTOPT_GQUOTANOENF "gqnoenforce"/* group quota limit enforcement */
 #define MNTOPT_PQUOTANOENF "pqnoenforce"/* project quota limit enforcement */
 #define MNTOPT_QUOTANOENF  "qnoenforce"	/* same as uqnoenforce */
-#define MNTOPT_DELAYLOG   "delaylog"	/* Delayed loging enabled */
-#define MNTOPT_NODELAYLOG "nodelaylog"	/* Delayed loging disabled */
+#define MNTOPT_DELAYLOG    "delaylog"	/* Delayed logging enabled */
+#define MNTOPT_NODELAYLOG  "nodelaylog"	/* Delayed logging disabled */
+#define MNTOPT_DISCARD	   "discard"	/* Discard unused blocks */
+#define MNTOPT_NODISCARD   "nodiscard"	/* Do not discard unused blocks */
 
 /*
  * Table driven mount option parser.
@@ -355,6 +357,10 @@ xfs_parseargs(
 			mp->m_flags |= XFS_MOUNT_DELAYLOG;
 		} else if (!strcmp(this_char, MNTOPT_NODELAYLOG)) {
 			mp->m_flags &= ~XFS_MOUNT_DELAYLOG;
+		} else if (!strcmp(this_char, MNTOPT_DISCARD)) {
+			mp->m_flags |= XFS_MOUNT_DISCARD;
+		} else if (!strcmp(this_char, MNTOPT_NODISCARD)) {
+			mp->m_flags &= ~XFS_MOUNT_DISCARD;
 		} else if (!strcmp(this_char, "ihashsize")) {
 			xfs_warn(mp,
 	"ihashsize no longer used, option is deprecated.");
@@ -388,6 +394,13 @@ xfs_parseargs(
 		return EINVAL;
 	}
 
+	if ((mp->m_flags & XFS_MOUNT_DISCARD) &&
+	    !(mp->m_flags & XFS_MOUNT_DELAYLOG)) {
+		xfs_warn(mp,
+	"the discard option is incompatible with the nodelaylog option");
+		return EINVAL;
+	}
+
 #ifndef CONFIG_XFS_QUOTA
 	if (XFS_IS_QUOTA_RUNNING(mp)) {
 		xfs_warn(mp, "quota support not available in this kernel.");
@@ -488,6 +501,7 @@ xfs_showargs(
 		{ XFS_MOUNT_FILESTREAMS,	"," MNTOPT_FILESTREAM },
 		{ XFS_MOUNT_GRPID,		"," MNTOPT_GRPID },
 		{ XFS_MOUNT_DELAYLOG,		"," MNTOPT_DELAYLOG },
+		{ XFS_MOUNT_DISCARD,		"," MNTOPT_DISCARD },
 		{ 0, NULL }
 	};
 	static struct proc_xfs_info xfs_info_unset[] = {
diff --git a/fs/xfs/xfs_ag.h b/fs/xfs/xfs_ag.h
index da0a561ffba2..6530769a999b 100644
--- a/fs/xfs/xfs_ag.h
+++ b/fs/xfs/xfs_ag.h
@@ -187,6 +187,9 @@ struct xfs_busy_extent {
 	xfs_agnumber_t	agno;
 	xfs_agblock_t	bno;
 	xfs_extlen_t	length;
+	unsigned int	flags;
+#define XFS_ALLOC_BUSY_DISCARDED	0x01	/* undergoing a discard op. */
+#define XFS_ALLOC_BUSY_SKIP_DISCARD	0x02	/* do not discard */
 };
 
 /*
diff --git a/fs/xfs/xfs_alloc.c b/fs/xfs/xfs_alloc.c
index acdced86413c..95862bbff56b 100644
--- a/fs/xfs/xfs_alloc.c
+++ b/fs/xfs/xfs_alloc.c
@@ -2469,7 +2469,7 @@ xfs_free_extent(
 
 	error = xfs_free_ag_extent(tp, args.agbp, args.agno, args.agbno, len, 0);
 	if (!error)
-		xfs_alloc_busy_insert(tp, args.agno, args.agbno, len);
+		xfs_alloc_busy_insert(tp, args.agno, args.agbno, len, 0);
 error0:
 	xfs_perag_put(args.pag);
 	return error;
@@ -2480,7 +2480,8 @@ xfs_alloc_busy_insert(
 	struct xfs_trans	*tp,
 	xfs_agnumber_t		agno,
 	xfs_agblock_t		bno,
-	xfs_extlen_t		len)
+	xfs_extlen_t		len,
+	unsigned int		flags)
 {
 	struct xfs_busy_extent	*new;
 	struct xfs_busy_extent	*busyp;
@@ -2504,6 +2505,7 @@ xfs_alloc_busy_insert(
 	new->bno = bno;
 	new->length = len;
 	INIT_LIST_HEAD(&new->list);
+	new->flags = flags;
 
 	/* trace before insert to be able to see failed inserts */
 	trace_xfs_alloc_busy(tp->t_mountp, agno, bno, len);
@@ -2609,6 +2611,18 @@ xfs_alloc_busy_update_extent(
 	xfs_agblock_t		bend = bbno + busyp->length;
 
 	/*
+	 * This extent is currently being discarded.  Give the thread
+	 * performing the discard a chance to mark the extent unbusy
+	 * and retry.
+	 */
+	if (busyp->flags & XFS_ALLOC_BUSY_DISCARDED) {
+		spin_unlock(&pag->pagb_lock);
+		delay(1);
+		spin_lock(&pag->pagb_lock);
+		return false;
+	}
+
+	/*
 	 * If there is a busy extent overlapping a user allocation, we have
 	 * no choice but to force the log and retry the search.
 	 *
@@ -2813,7 +2827,8 @@ restart:
 		 * If this is a metadata allocation, try to reuse the busy
 		 * extent instead of trimming the allocation.
 		 */
-		if (!args->userdata) {
+		if (!args->userdata &&
+		    !(busyp->flags & XFS_ALLOC_BUSY_DISCARDED)) {
 			if (!xfs_alloc_busy_update_extent(args->mp, args->pag,
 							  busyp, fbno, flen,
 							  false))
@@ -2979,10 +2994,16 @@ xfs_alloc_busy_clear_one(
 	kmem_free(busyp);
 }
 
+/*
+ * Remove all extents on the passed in list from the busy extents tree.
+ * If do_discard is set skip extents that need to be discarded, and mark
+ * these as undergoing a discard operation instead.
+ */
 void
 xfs_alloc_busy_clear(
 	struct xfs_mount	*mp,
-	struct list_head	*list)
+	struct list_head	*list,
+	bool			do_discard)
 {
 	struct xfs_busy_extent	*busyp, *n;
 	struct xfs_perag	*pag = NULL;
@@ -2999,7 +3020,11 @@ xfs_alloc_busy_clear(
 			agno = busyp->agno;
 		}
 
-		xfs_alloc_busy_clear_one(mp, pag, busyp);
+		if (do_discard && busyp->length &&
+		    !(busyp->flags & XFS_ALLOC_BUSY_SKIP_DISCARD))
+			busyp->flags = XFS_ALLOC_BUSY_DISCARDED;
+		else
+			xfs_alloc_busy_clear_one(mp, pag, busyp);
 	}
 
 	if (pag) {
diff --git a/fs/xfs/xfs_alloc.h b/fs/xfs/xfs_alloc.h
index 240ad288f2f9..2f52b924be79 100644
--- a/fs/xfs/xfs_alloc.h
+++ b/fs/xfs/xfs_alloc.h
@@ -137,10 +137,11 @@ xfs_alloc_longest_free_extent(struct xfs_mount *mp,
 #ifdef __KERNEL__
 void
 xfs_alloc_busy_insert(struct xfs_trans *tp, xfs_agnumber_t agno,
-	xfs_agblock_t bno, xfs_extlen_t len);
+	xfs_agblock_t bno, xfs_extlen_t len, unsigned int flags);
 
 void
-xfs_alloc_busy_clear(struct xfs_mount *mp, struct list_head *list);
+xfs_alloc_busy_clear(struct xfs_mount *mp, struct list_head *list,
+	bool do_discard);
 
 int
 xfs_alloc_busy_search(struct xfs_mount *mp, xfs_agnumber_t agno,
diff --git a/fs/xfs/xfs_alloc_btree.c b/fs/xfs/xfs_alloc_btree.c
index 8b469d53599f..2b3518826a69 100644
--- a/fs/xfs/xfs_alloc_btree.c
+++ b/fs/xfs/xfs_alloc_btree.c
@@ -120,7 +120,8 @@ xfs_allocbt_free_block(
 	if (error)
 		return error;
 
-	xfs_alloc_busy_insert(cur->bc_tp, be32_to_cpu(agf->agf_seqno), bno, 1);
+	xfs_alloc_busy_insert(cur->bc_tp, be32_to_cpu(agf->agf_seqno), bno, 1,
+			      XFS_ALLOC_BUSY_SKIP_DISCARD);
 	xfs_trans_agbtree_delta(cur->bc_tp, -1);
 	return 0;
 }
diff --git a/fs/xfs/xfs_bmap.c b/fs/xfs/xfs_bmap.c
index fa00788de2f5..e546a33214c9 100644
--- a/fs/xfs/xfs_bmap.c
+++ b/fs/xfs/xfs_bmap.c
@@ -89,36 +89,19 @@ xfs_bmap_add_attrfork_local(
 	int			*flags);	/* inode logging flags */
 
 /*
- * Called by xfs_bmapi to update file extent records and the btree
- * after allocating space (or doing a delayed allocation).
- */
-STATIC int				/* error */
-xfs_bmap_add_extent(
-	xfs_inode_t		*ip,	/* incore inode pointer */
-	xfs_extnum_t		idx,	/* extent number to update/insert */
-	xfs_btree_cur_t		**curp,	/* if *curp is null, not a btree */
-	xfs_bmbt_irec_t		*new,	/* new data to add to file extents */
-	xfs_fsblock_t		*first,	/* pointer to firstblock variable */
-	xfs_bmap_free_t		*flist,	/* list of extents to be freed */
-	int			*logflagsp, /* inode logging flags */
-	int			whichfork, /* data or attr fork */
-	int			rsvd);	/* OK to allocate reserved blocks */
-
-/*
  * Called by xfs_bmap_add_extent to handle cases converting a delayed
  * allocation to a real allocation.
  */
 STATIC int				/* error */
 xfs_bmap_add_extent_delay_real(
 	xfs_inode_t		*ip,	/* incore inode pointer */
-	xfs_extnum_t		idx,	/* extent number to update/insert */
+	xfs_extnum_t		*idx,	/* extent number to update/insert */
 	xfs_btree_cur_t		**curp,	/* if *curp is null, not a btree */
 	xfs_bmbt_irec_t		*new,	/* new data to add to file extents */
 	xfs_filblks_t		*dnew,	/* new delayed-alloc indirect blocks */
 	xfs_fsblock_t		*first,	/* pointer to firstblock variable */
 	xfs_bmap_free_t		*flist,	/* list of extents to be freed */
-	int			*logflagsp, /* inode logging flags */
-	int			rsvd);	/* OK to allocate reserved blocks */
+	int			*logflagsp); /* inode logging flags */
 
 /*
  * Called by xfs_bmap_add_extent to handle cases converting a hole
@@ -127,10 +110,9 @@ xfs_bmap_add_extent_delay_real(
 STATIC int				/* error */
 xfs_bmap_add_extent_hole_delay(
 	xfs_inode_t		*ip,	/* incore inode pointer */
-	xfs_extnum_t		idx,	/* extent number to update/insert */
+	xfs_extnum_t		*idx,	/* extent number to update/insert */
 	xfs_bmbt_irec_t		*new,	/* new data to add to file extents */
-	int			*logflagsp,/* inode logging flags */
-	int			rsvd);	/* OK to allocate reserved blocks */
+	int			*logflagsp); /* inode logging flags */
 
 /*
  * Called by xfs_bmap_add_extent to handle cases converting a hole
@@ -139,7 +121,7 @@ xfs_bmap_add_extent_hole_delay(
 STATIC int				/* error */
 xfs_bmap_add_extent_hole_real(
 	xfs_inode_t		*ip,	/* incore inode pointer */
-	xfs_extnum_t		idx,	/* extent number to update/insert */
+	xfs_extnum_t		*idx,	/* extent number to update/insert */
 	xfs_btree_cur_t		*cur,	/* if null, not a btree */
 	xfs_bmbt_irec_t		*new,	/* new data to add to file extents */
 	int			*logflagsp, /* inode logging flags */
@@ -152,7 +134,7 @@ xfs_bmap_add_extent_hole_real(
 STATIC int				/* error */
 xfs_bmap_add_extent_unwritten_real(
 	xfs_inode_t		*ip,	/* incore inode pointer */
-	xfs_extnum_t		idx,	/* extent number to update/insert */
+	xfs_extnum_t		*idx,	/* extent number to update/insert */
 	xfs_btree_cur_t		**curp,	/* if *curp is null, not a btree */
 	xfs_bmbt_irec_t		*new,	/* new data to add to file extents */
 	int			*logflagsp); /* inode logging flags */
@@ -180,22 +162,6 @@ xfs_bmap_btree_to_extents(
 	int			whichfork); /* data or attr fork */
 
 /*
- * Called by xfs_bmapi to update file extent records and the btree
- * after removing space (or undoing a delayed allocation).
- */
-STATIC int				/* error */
-xfs_bmap_del_extent(
-	xfs_inode_t		*ip,	/* incore inode pointer */
-	xfs_trans_t		*tp,	/* current trans pointer */
-	xfs_extnum_t		idx,	/* extent number to update/insert */
-	xfs_bmap_free_t		*flist,	/* list of extents to be freed */
-	xfs_btree_cur_t		*cur,	/* if null, not a btree */
-	xfs_bmbt_irec_t		*new,	/* new data to add to file extents */
-	int			*logflagsp,/* inode logging flags */
-	int			whichfork, /* data or attr fork */
-	int			rsvd);	 /* OK to allocate reserved blocks */
-
-/*
  * Remove the entry "free" from the free item list.  Prev points to the
  * previous entry, unless "free" is the head of the list.
  */
@@ -474,14 +440,13 @@ xfs_bmap_add_attrfork_local(
 STATIC int				/* error */
 xfs_bmap_add_extent(
 	xfs_inode_t		*ip,	/* incore inode pointer */
-	xfs_extnum_t		idx,	/* extent number to update/insert */
+	xfs_extnum_t		*idx,	/* extent number to update/insert */
 	xfs_btree_cur_t		**curp,	/* if *curp is null, not a btree */
 	xfs_bmbt_irec_t		*new,	/* new data to add to file extents */
 	xfs_fsblock_t		*first,	/* pointer to firstblock variable */
 	xfs_bmap_free_t		*flist,	/* list of extents to be freed */
 	int			*logflagsp, /* inode logging flags */
-	int			whichfork, /* data or attr fork */
-	int			rsvd)	/* OK to use reserved data blocks */
+	int			whichfork) /* data or attr fork */
 {
 	xfs_btree_cur_t		*cur;	/* btree cursor or null */
 	xfs_filblks_t		da_new; /* new count del alloc blocks used */
@@ -492,23 +457,27 @@ xfs_bmap_add_extent(
 	xfs_extnum_t		nextents; /* number of extents in file now */
 
 	XFS_STATS_INC(xs_add_exlist);
+
 	cur = *curp;
 	ifp = XFS_IFORK_PTR(ip, whichfork);
 	nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
-	ASSERT(idx <= nextents);
 	da_old = da_new = 0;
 	error = 0;
+
+	ASSERT(*idx >= 0);
+	ASSERT(*idx <= nextents);
+
 	/*
 	 * This is the first extent added to a new/empty file.
 	 * Special case this one, so other routines get to assume there are
 	 * already extents in the list.
 	 */
 	if (nextents == 0) {
-		xfs_iext_insert(ip, 0, 1, new,
+		xfs_iext_insert(ip, *idx, 1, new,
 				whichfork == XFS_ATTR_FORK ? BMAP_ATTRFORK : 0);
 
 		ASSERT(cur == NULL);
-		ifp->if_lastex = 0;
+
 		if (!isnullstartblock(new->br_startblock)) {
 			XFS_IFORK_NEXT_SET(ip, whichfork, 1);
 			logflags = XFS_ILOG_CORE | xfs_ilog_fext(whichfork);
@@ -522,27 +491,25 @@ xfs_bmap_add_extent(
 		if (cur)
 			ASSERT((cur->bc_private.b.flags &
 				XFS_BTCUR_BPRV_WASDEL) == 0);
-		if ((error = xfs_bmap_add_extent_hole_delay(ip, idx, new,
-				&logflags, rsvd)))
-			goto done;
+		error = xfs_bmap_add_extent_hole_delay(ip, idx, new,
+						       &logflags);
 	}
 	/*
 	 * Real allocation off the end of the file.
 	 */
-	else if (idx == nextents) {
+	else if (*idx == nextents) {
 		if (cur)
 			ASSERT((cur->bc_private.b.flags &
 				XFS_BTCUR_BPRV_WASDEL) == 0);
-		if ((error = xfs_bmap_add_extent_hole_real(ip, idx, cur, new,
-				&logflags, whichfork)))
-			goto done;
+		error = xfs_bmap_add_extent_hole_real(ip, idx, cur, new,
+				&logflags, whichfork);
 	} else {
 		xfs_bmbt_irec_t	prev;	/* old extent at offset idx */
 
 		/*
 		 * Get the record referred to by idx.
 		 */
-		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, idx), &prev);
+		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, *idx), &prev);
 		/*
 		 * If it's a real allocation record, and the new allocation ends
 		 * after the start of the referred to record, then we're filling
@@ -557,22 +524,18 @@ xfs_bmap_add_extent(
 				if (cur)
 					ASSERT(cur->bc_private.b.flags &
 						XFS_BTCUR_BPRV_WASDEL);
-				if ((error = xfs_bmap_add_extent_delay_real(ip,
-					idx, &cur, new, &da_new, first, flist,
-					&logflags, rsvd)))
-					goto done;
-			} else if (new->br_state == XFS_EXT_NORM) {
-				ASSERT(new->br_state == XFS_EXT_NORM);
-				if ((error = xfs_bmap_add_extent_unwritten_real(
-					ip, idx, &cur, new, &logflags)))
-					goto done;
+				error = xfs_bmap_add_extent_delay_real(ip,
+						idx, &cur, new, &da_new,
+						first, flist, &logflags);
 			} else {
-				ASSERT(new->br_state == XFS_EXT_UNWRITTEN);
-				if ((error = xfs_bmap_add_extent_unwritten_real(
-					ip, idx, &cur, new, &logflags)))
+				ASSERT(new->br_state == XFS_EXT_NORM ||
+				       new->br_state == XFS_EXT_UNWRITTEN);
+
+				error = xfs_bmap_add_extent_unwritten_real(ip,
+						idx, &cur, new, &logflags);
+				if (error)
 					goto done;
 			}
-			ASSERT(*curp == cur || *curp == NULL);
 		}
 		/*
 		 * Otherwise we're filling in a hole with an allocation.
@@ -581,13 +544,15 @@ xfs_bmap_add_extent(
 			if (cur)
 				ASSERT((cur->bc_private.b.flags &
 					XFS_BTCUR_BPRV_WASDEL) == 0);
-			if ((error = xfs_bmap_add_extent_hole_real(ip, idx, cur,
-					new, &logflags, whichfork)))
-				goto done;
+			error = xfs_bmap_add_extent_hole_real(ip, idx, cur,
+					new, &logflags, whichfork);
 		}
 	}
 
+	if (error)
+		goto done;
 	ASSERT(*curp == cur || *curp == NULL);
+
 	/*
 	 * Convert to a btree if necessary.
 	 */
@@ -615,7 +580,7 @@ xfs_bmap_add_extent(
 		ASSERT(nblks <= da_old);
 		if (nblks < da_old)
 			xfs_icsb_modify_counters(ip->i_mount, XFS_SBS_FDBLOCKS,
-				(int64_t)(da_old - nblks), rsvd);
+				(int64_t)(da_old - nblks), 0);
 	}
 	/*
 	 * Clear out the allocated field, done with it now in any case.
@@ -640,14 +605,13 @@ done:
 STATIC int				/* error */
 xfs_bmap_add_extent_delay_real(
 	xfs_inode_t		*ip,	/* incore inode pointer */
-	xfs_extnum_t		idx,	/* extent number to update/insert */
+	xfs_extnum_t		*idx,	/* extent number to update/insert */
 	xfs_btree_cur_t		**curp,	/* if *curp is null, not a btree */
 	xfs_bmbt_irec_t		*new,	/* new data to add to file extents */
 	xfs_filblks_t		*dnew,	/* new delayed-alloc indirect blocks */
 	xfs_fsblock_t		*first,	/* pointer to firstblock variable */
 	xfs_bmap_free_t		*flist,	/* list of extents to be freed */
-	int			*logflagsp, /* inode logging flags */
-	int			rsvd)	/* OK to use reserved data block allocation */
+	int			*logflagsp) /* inode logging flags */
 {
 	xfs_btree_cur_t		*cur;	/* btree cursor */
 	int			diff;	/* temp value */
@@ -673,7 +637,7 @@ xfs_bmap_add_extent_delay_real(
 	 */
 	cur = *curp;
 	ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
-	ep = xfs_iext_get_ext(ifp, idx);
+	ep = xfs_iext_get_ext(ifp, *idx);
 	xfs_bmbt_get_all(ep, &PREV);
 	new_endoff = new->br_startoff + new->br_blockcount;
 	ASSERT(PREV.br_startoff <= new->br_startoff);
@@ -692,9 +656,9 @@ xfs_bmap_add_extent_delay_real(
 	 * Check and set flags if this segment has a left neighbor.
 	 * Don't set contiguous if the combined extent would be too large.
 	 */
-	if (idx > 0) {
+	if (*idx > 0) {
 		state |= BMAP_LEFT_VALID;
-		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, idx - 1), &LEFT);
+		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, *idx - 1), &LEFT);
 
 		if (isnullstartblock(LEFT.br_startblock))
 			state |= BMAP_LEFT_DELAY;
@@ -712,9 +676,9 @@ xfs_bmap_add_extent_delay_real(
 	 * Don't set contiguous if the combined extent would be too large.
 	 * Also check for all-three-contiguous being too large.
 	 */
-	if (idx < ip->i_df.if_bytes / (uint)sizeof(xfs_bmbt_rec_t) - 1) {
+	if (*idx < ip->i_df.if_bytes / (uint)sizeof(xfs_bmbt_rec_t) - 1) {
 		state |= BMAP_RIGHT_VALID;
-		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, idx + 1), &RIGHT);
+		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, *idx + 1), &RIGHT);
 
 		if (isnullstartblock(RIGHT.br_startblock))
 			state |= BMAP_RIGHT_DELAY;
@@ -745,14 +709,14 @@ xfs_bmap_add_extent_delay_real(
 		 * Filling in all of a previously delayed allocation extent.
 		 * The left and right neighbors are both contiguous with new.
 		 */
-		trace_xfs_bmap_pre_update(ip, idx - 1, state, _THIS_IP_);
-		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, idx - 1),
+		--*idx;
+		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
+		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, *idx),
 			LEFT.br_blockcount + PREV.br_blockcount +
 			RIGHT.br_blockcount);
-		trace_xfs_bmap_post_update(ip, idx - 1, state, _THIS_IP_);
+		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 
-		xfs_iext_remove(ip, idx, 2, state);
-		ip->i_df.if_lastex = idx - 1;
+		xfs_iext_remove(ip, *idx + 1, 2, state);
 		ip->i_d.di_nextents--;
 		if (cur == NULL)
 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
@@ -784,13 +748,14 @@ xfs_bmap_add_extent_delay_real(
 		 * Filling in all of a previously delayed allocation extent.
 		 * The left neighbor is contiguous, the right is not.
 		 */
-		trace_xfs_bmap_pre_update(ip, idx - 1, state, _THIS_IP_);
-		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, idx - 1),
+		--*idx;
+
+		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
+		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, *idx),
 			LEFT.br_blockcount + PREV.br_blockcount);
-		trace_xfs_bmap_post_update(ip, idx - 1, state, _THIS_IP_);
+		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 
-		ip->i_df.if_lastex = idx - 1;
-		xfs_iext_remove(ip, idx, 1, state);
+		xfs_iext_remove(ip, *idx + 1, 1, state);
 		if (cur == NULL)
 			rval = XFS_ILOG_DEXT;
 		else {
@@ -814,14 +779,13 @@ xfs_bmap_add_extent_delay_real(
 		 * Filling in all of a previously delayed allocation extent.
 		 * The right neighbor is contiguous, the left is not.
 		 */
-		trace_xfs_bmap_pre_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
 		xfs_bmbt_set_startblock(ep, new->br_startblock);
 		xfs_bmbt_set_blockcount(ep,
 			PREV.br_blockcount + RIGHT.br_blockcount);
-		trace_xfs_bmap_post_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 
-		ip->i_df.if_lastex = idx;
-		xfs_iext_remove(ip, idx + 1, 1, state);
+		xfs_iext_remove(ip, *idx + 1, 1, state);
 		if (cur == NULL)
 			rval = XFS_ILOG_DEXT;
 		else {
@@ -837,6 +801,7 @@ xfs_bmap_add_extent_delay_real(
 					RIGHT.br_blockcount, PREV.br_state)))
 				goto done;
 		}
+
 		*dnew = 0;
 		break;
 
@@ -846,11 +811,10 @@ xfs_bmap_add_extent_delay_real(
 		 * Neither the left nor right neighbors are contiguous with
 		 * the new one.
 		 */
-		trace_xfs_bmap_pre_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
 		xfs_bmbt_set_startblock(ep, new->br_startblock);
-		trace_xfs_bmap_post_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 
-		ip->i_df.if_lastex = idx;
 		ip->i_d.di_nextents++;
 		if (cur == NULL)
 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
@@ -866,6 +830,7 @@ xfs_bmap_add_extent_delay_real(
 				goto done;
 			XFS_WANT_CORRUPTED_GOTO(i == 1, done);
 		}
+
 		*dnew = 0;
 		break;
 
@@ -874,17 +839,16 @@ xfs_bmap_add_extent_delay_real(
 		 * Filling in the first part of a previous delayed allocation.
 		 * The left neighbor is contiguous.
 		 */
-		trace_xfs_bmap_pre_update(ip, idx - 1, state, _THIS_IP_);
-		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, idx - 1),
+		trace_xfs_bmap_pre_update(ip, *idx - 1, state, _THIS_IP_);
+		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, *idx - 1),
 			LEFT.br_blockcount + new->br_blockcount);
 		xfs_bmbt_set_startoff(ep,
 			PREV.br_startoff + new->br_blockcount);
-		trace_xfs_bmap_post_update(ip, idx - 1, state, _THIS_IP_);
+		trace_xfs_bmap_post_update(ip, *idx - 1, state, _THIS_IP_);
 
 		temp = PREV.br_blockcount - new->br_blockcount;
-		trace_xfs_bmap_pre_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
 		xfs_bmbt_set_blockcount(ep, temp);
-		ip->i_df.if_lastex = idx - 1;
 		if (cur == NULL)
 			rval = XFS_ILOG_DEXT;
 		else {
@@ -904,7 +868,9 @@ xfs_bmap_add_extent_delay_real(
 		temp = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip, temp),
 			startblockval(PREV.br_startblock));
 		xfs_bmbt_set_startblock(ep, nullstartblock((int)temp));
-		trace_xfs_bmap_post_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
+
+		--*idx;
 		*dnew = temp;
 		break;
 
@@ -913,12 +879,11 @@ xfs_bmap_add_extent_delay_real(
 		 * Filling in the first part of a previous delayed allocation.
 		 * The left neighbor is not contiguous.
 		 */
-		trace_xfs_bmap_pre_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
 		xfs_bmbt_set_startoff(ep, new_endoff);
 		temp = PREV.br_blockcount - new->br_blockcount;
 		xfs_bmbt_set_blockcount(ep, temp);
-		xfs_iext_insert(ip, idx, 1, new, state);
-		ip->i_df.if_lastex = idx;
+		xfs_iext_insert(ip, *idx, 1, new, state);
 		ip->i_d.di_nextents++;
 		if (cur == NULL)
 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
@@ -946,9 +911,10 @@ xfs_bmap_add_extent_delay_real(
 		temp = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip, temp),
 			startblockval(PREV.br_startblock) -
 			(cur ? cur->bc_private.b.allocated : 0));
-		ep = xfs_iext_get_ext(ifp, idx + 1);
+		ep = xfs_iext_get_ext(ifp, *idx + 1);
 		xfs_bmbt_set_startblock(ep, nullstartblock((int)temp));
-		trace_xfs_bmap_post_update(ip, idx + 1, state, _THIS_IP_);
+		trace_xfs_bmap_post_update(ip, *idx + 1, state, _THIS_IP_);
+
 		*dnew = temp;
 		break;
 
@@ -958,15 +924,13 @@ xfs_bmap_add_extent_delay_real(
 		 * The right neighbor is contiguous with the new allocation.
 		 */
 		temp = PREV.br_blockcount - new->br_blockcount;
-		trace_xfs_bmap_pre_update(ip, idx, state, _THIS_IP_);
-		trace_xfs_bmap_pre_update(ip, idx + 1, state, _THIS_IP_);
+		trace_xfs_bmap_pre_update(ip, *idx + 1, state, _THIS_IP_);
 		xfs_bmbt_set_blockcount(ep, temp);
-		xfs_bmbt_set_allf(xfs_iext_get_ext(ifp, idx + 1),
+		xfs_bmbt_set_allf(xfs_iext_get_ext(ifp, *idx + 1),
 			new->br_startoff, new->br_startblock,
 			new->br_blockcount + RIGHT.br_blockcount,
 			RIGHT.br_state);
-		trace_xfs_bmap_post_update(ip, idx + 1, state, _THIS_IP_);
-		ip->i_df.if_lastex = idx + 1;
+		trace_xfs_bmap_post_update(ip, *idx + 1, state, _THIS_IP_);
 		if (cur == NULL)
 			rval = XFS_ILOG_DEXT;
 		else {
@@ -983,10 +947,14 @@ xfs_bmap_add_extent_delay_real(
 					RIGHT.br_state)))
 				goto done;
 		}
+
 		temp = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip, temp),
 			startblockval(PREV.br_startblock));
+		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
 		xfs_bmbt_set_startblock(ep, nullstartblock((int)temp));
-		trace_xfs_bmap_post_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
+
+		++*idx;
 		*dnew = temp;
 		break;
 
@@ -996,10 +964,9 @@ xfs_bmap_add_extent_delay_real(
 		 * The right neighbor is not contiguous.
 		 */
 		temp = PREV.br_blockcount - new->br_blockcount;
-		trace_xfs_bmap_pre_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
 		xfs_bmbt_set_blockcount(ep, temp);
-		xfs_iext_insert(ip, idx + 1, 1, new, state);
-		ip->i_df.if_lastex = idx + 1;
+		xfs_iext_insert(ip, *idx + 1, 1, new, state);
 		ip->i_d.di_nextents++;
 		if (cur == NULL)
 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
@@ -1027,9 +994,11 @@ xfs_bmap_add_extent_delay_real(
 		temp = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip, temp),
 			startblockval(PREV.br_startblock) -
 			(cur ? cur->bc_private.b.allocated : 0));
-		ep = xfs_iext_get_ext(ifp, idx);
+		ep = xfs_iext_get_ext(ifp, *idx);
 		xfs_bmbt_set_startblock(ep, nullstartblock((int)temp));
-		trace_xfs_bmap_post_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
+
+		++*idx;
 		*dnew = temp;
 		break;
 
@@ -1056,7 +1025,7 @@ xfs_bmap_add_extent_delay_real(
 		 */
 		temp = new->br_startoff - PREV.br_startoff;
 		temp2 = PREV.br_startoff + PREV.br_blockcount - new_endoff;
-		trace_xfs_bmap_pre_update(ip, idx, 0, _THIS_IP_);
+		trace_xfs_bmap_pre_update(ip, *idx, 0, _THIS_IP_);
 		xfs_bmbt_set_blockcount(ep, temp);	/* truncate PREV */
 		LEFT = *new;
 		RIGHT.br_state = PREV.br_state;
@@ -1065,8 +1034,7 @@ xfs_bmap_add_extent_delay_real(
 		RIGHT.br_startoff = new_endoff;
 		RIGHT.br_blockcount = temp2;
 		/* insert LEFT (r[0]) and RIGHT (r[1]) at the same time */
-		xfs_iext_insert(ip, idx + 1, 2, &LEFT, state);
-		ip->i_df.if_lastex = idx + 1;
+		xfs_iext_insert(ip, *idx + 1, 2, &LEFT, state);
 		ip->i_d.di_nextents++;
 		if (cur == NULL)
 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
@@ -1097,7 +1065,7 @@ xfs_bmap_add_extent_delay_real(
 			(cur ? cur->bc_private.b.allocated : 0));
 		if (diff > 0 &&
 		    xfs_icsb_modify_counters(ip->i_mount, XFS_SBS_FDBLOCKS,
-					     -((int64_t)diff), rsvd)) {
+					     -((int64_t)diff), 0)) {
 			/*
 			 * Ick gross gag me with a spoon.
 			 */
@@ -1109,7 +1077,7 @@ xfs_bmap_add_extent_delay_real(
 					if (!diff ||
 					    !xfs_icsb_modify_counters(ip->i_mount,
 						    XFS_SBS_FDBLOCKS,
-						    -((int64_t)diff), rsvd))
+						    -((int64_t)diff), 0))
 						break;
 				}
 				if (temp2) {
@@ -1118,18 +1086,20 @@ xfs_bmap_add_extent_delay_real(
 					if (!diff ||
 					    !xfs_icsb_modify_counters(ip->i_mount,
 						    XFS_SBS_FDBLOCKS,
-						    -((int64_t)diff), rsvd))
+						    -((int64_t)diff), 0))
 						break;
 				}
 			}
 		}
-		ep = xfs_iext_get_ext(ifp, idx);
+		ep = xfs_iext_get_ext(ifp, *idx);
 		xfs_bmbt_set_startblock(ep, nullstartblock((int)temp));
-		trace_xfs_bmap_post_update(ip, idx, state, _THIS_IP_);
-		trace_xfs_bmap_pre_update(ip, idx + 2, state, _THIS_IP_);
-		xfs_bmbt_set_startblock(xfs_iext_get_ext(ifp, idx + 2),
+		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
+		trace_xfs_bmap_pre_update(ip, *idx + 2, state, _THIS_IP_);
+		xfs_bmbt_set_startblock(xfs_iext_get_ext(ifp, *idx + 2),
 			nullstartblock((int)temp2));
-		trace_xfs_bmap_post_update(ip, idx + 2, state, _THIS_IP_);
+		trace_xfs_bmap_post_update(ip, *idx + 2, state, _THIS_IP_);
+
+		++*idx;
 		*dnew = temp + temp2;
 		break;
 
@@ -1161,7 +1131,7 @@ done:
 STATIC int				/* error */
 xfs_bmap_add_extent_unwritten_real(
 	xfs_inode_t		*ip,	/* incore inode pointer */
-	xfs_extnum_t		idx,	/* extent number to update/insert */
+	xfs_extnum_t		*idx,	/* extent number to update/insert */
 	xfs_btree_cur_t		**curp,	/* if *curp is null, not a btree */
 	xfs_bmbt_irec_t		*new,	/* new data to add to file extents */
 	int			*logflagsp) /* inode logging flags */
@@ -1188,7 +1158,7 @@ xfs_bmap_add_extent_unwritten_real(
 	error = 0;
 	cur = *curp;
 	ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
-	ep = xfs_iext_get_ext(ifp, idx);
+	ep = xfs_iext_get_ext(ifp, *idx);
 	xfs_bmbt_get_all(ep, &PREV);
 	newext = new->br_state;
 	oldext = (newext == XFS_EXT_UNWRITTEN) ?
@@ -1211,9 +1181,9 @@ xfs_bmap_add_extent_unwritten_real(
 	 * Check and set flags if this segment has a left neighbor.
 	 * Don't set contiguous if the combined extent would be too large.
 	 */
-	if (idx > 0) {
+	if (*idx > 0) {
 		state |= BMAP_LEFT_VALID;
-		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, idx - 1), &LEFT);
+		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, *idx - 1), &LEFT);
 
 		if (isnullstartblock(LEFT.br_startblock))
 			state |= BMAP_LEFT_DELAY;
@@ -1231,9 +1201,9 @@ xfs_bmap_add_extent_unwritten_real(
 	 * Don't set contiguous if the combined extent would be too large.
 	 * Also check for all-three-contiguous being too large.
 	 */
-	if (idx < ip->i_df.if_bytes / (uint)sizeof(xfs_bmbt_rec_t) - 1) {
+	if (*idx < ip->i_df.if_bytes / (uint)sizeof(xfs_bmbt_rec_t) - 1) {
 		state |= BMAP_RIGHT_VALID;
-		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, idx + 1), &RIGHT);
+		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, *idx + 1), &RIGHT);
 		if (isnullstartblock(RIGHT.br_startblock))
 			state |= BMAP_RIGHT_DELAY;
 	}
@@ -1262,14 +1232,15 @@ xfs_bmap_add_extent_unwritten_real(
 		 * Setting all of a previous oldext extent to newext.
 		 * The left and right neighbors are both contiguous with new.
 		 */
-		trace_xfs_bmap_pre_update(ip, idx - 1, state, _THIS_IP_);
-		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, idx - 1),
+		--*idx;
+
+		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
+		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, *idx),
 			LEFT.br_blockcount + PREV.br_blockcount +
 			RIGHT.br_blockcount);
-		trace_xfs_bmap_post_update(ip, idx - 1, state, _THIS_IP_);
+		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 
-		xfs_iext_remove(ip, idx, 2, state);
-		ip->i_df.if_lastex = idx - 1;
+		xfs_iext_remove(ip, *idx + 1, 2, state);
 		ip->i_d.di_nextents -= 2;
 		if (cur == NULL)
 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
@@ -1305,13 +1276,14 @@ xfs_bmap_add_extent_unwritten_real(
 		 * Setting all of a previous oldext extent to newext.
 		 * The left neighbor is contiguous, the right is not.
 		 */
-		trace_xfs_bmap_pre_update(ip, idx - 1, state, _THIS_IP_);
-		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, idx - 1),
+		--*idx;
+
+		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
+		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, *idx),
 			LEFT.br_blockcount + PREV.br_blockcount);
-		trace_xfs_bmap_post_update(ip, idx - 1, state, _THIS_IP_);
+		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 
-		ip->i_df.if_lastex = idx - 1;
-		xfs_iext_remove(ip, idx, 1, state);
+		xfs_iext_remove(ip, *idx + 1, 1, state);
 		ip->i_d.di_nextents--;
 		if (cur == NULL)
 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
@@ -1341,13 +1313,12 @@ xfs_bmap_add_extent_unwritten_real(
 		 * Setting all of a previous oldext extent to newext.
 		 * The right neighbor is contiguous, the left is not.
 		 */
-		trace_xfs_bmap_pre_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
 		xfs_bmbt_set_blockcount(ep,
 			PREV.br_blockcount + RIGHT.br_blockcount);
 		xfs_bmbt_set_state(ep, newext);
-		trace_xfs_bmap_post_update(ip, idx, state, _THIS_IP_);
-		ip->i_df.if_lastex = idx;
-		xfs_iext_remove(ip, idx + 1, 1, state);
+		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
+		xfs_iext_remove(ip, *idx + 1, 1, state);
 		ip->i_d.di_nextents--;
 		if (cur == NULL)
 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
@@ -1378,11 +1349,10 @@ xfs_bmap_add_extent_unwritten_real(
 		 * Neither the left nor right neighbors are contiguous with
 		 * the new one.
 		 */
-		trace_xfs_bmap_pre_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
 		xfs_bmbt_set_state(ep, newext);
-		trace_xfs_bmap_post_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 
-		ip->i_df.if_lastex = idx;
 		if (cur == NULL)
 			rval = XFS_ILOG_DEXT;
 		else {
@@ -1404,21 +1374,22 @@ xfs_bmap_add_extent_unwritten_real(
 		 * Setting the first part of a previous oldext extent to newext.
 		 * The left neighbor is contiguous.
 		 */
-		trace_xfs_bmap_pre_update(ip, idx - 1, state, _THIS_IP_);
-		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, idx - 1),
+		trace_xfs_bmap_pre_update(ip, *idx - 1, state, _THIS_IP_);
+		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, *idx - 1),
 			LEFT.br_blockcount + new->br_blockcount);
 		xfs_bmbt_set_startoff(ep,
 			PREV.br_startoff + new->br_blockcount);
-		trace_xfs_bmap_post_update(ip, idx - 1, state, _THIS_IP_);
+		trace_xfs_bmap_post_update(ip, *idx - 1, state, _THIS_IP_);
 
-		trace_xfs_bmap_pre_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
 		xfs_bmbt_set_startblock(ep,
 			new->br_startblock + new->br_blockcount);
 		xfs_bmbt_set_blockcount(ep,
 			PREV.br_blockcount - new->br_blockcount);
-		trace_xfs_bmap_post_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
+
+		--*idx;
 
-		ip->i_df.if_lastex = idx - 1;
 		if (cur == NULL)
 			rval = XFS_ILOG_DEXT;
 		else {
@@ -1449,17 +1420,16 @@ xfs_bmap_add_extent_unwritten_real(
 		 * Setting the first part of a previous oldext extent to newext.
 		 * The left neighbor is not contiguous.
 		 */
-		trace_xfs_bmap_pre_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
 		ASSERT(ep && xfs_bmbt_get_state(ep) == oldext);
 		xfs_bmbt_set_startoff(ep, new_endoff);
 		xfs_bmbt_set_blockcount(ep,
 			PREV.br_blockcount - new->br_blockcount);
 		xfs_bmbt_set_startblock(ep,
 			new->br_startblock + new->br_blockcount);
-		trace_xfs_bmap_post_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 
-		xfs_iext_insert(ip, idx, 1, new, state);
-		ip->i_df.if_lastex = idx;
+		xfs_iext_insert(ip, *idx, 1, new, state);
 		ip->i_d.di_nextents++;
 		if (cur == NULL)
 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
@@ -1488,17 +1458,19 @@ xfs_bmap_add_extent_unwritten_real(
 		 * Setting the last part of a previous oldext extent to newext.
 		 * The right neighbor is contiguous with the new allocation.
 		 */
-		trace_xfs_bmap_pre_update(ip, idx, state, _THIS_IP_);
-		trace_xfs_bmap_pre_update(ip, idx + 1, state, _THIS_IP_);
+		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
 		xfs_bmbt_set_blockcount(ep,
 			PREV.br_blockcount - new->br_blockcount);
-		trace_xfs_bmap_post_update(ip, idx, state, _THIS_IP_);
-		xfs_bmbt_set_allf(xfs_iext_get_ext(ifp, idx + 1),
+		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
+
+		++*idx;
+
+		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
+		xfs_bmbt_set_allf(xfs_iext_get_ext(ifp, *idx),
 			new->br_startoff, new->br_startblock,
 			new->br_blockcount + RIGHT.br_blockcount, newext);
-		trace_xfs_bmap_post_update(ip, idx + 1, state, _THIS_IP_);
+		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 
-		ip->i_df.if_lastex = idx + 1;
 		if (cur == NULL)
 			rval = XFS_ILOG_DEXT;
 		else {
@@ -1528,13 +1500,14 @@ xfs_bmap_add_extent_unwritten_real(
 		 * Setting the last part of a previous oldext extent to newext.
 		 * The right neighbor is not contiguous.
 		 */
-		trace_xfs_bmap_pre_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
 		xfs_bmbt_set_blockcount(ep,
 			PREV.br_blockcount - new->br_blockcount);
-		trace_xfs_bmap_post_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
+
+		++*idx;
+		xfs_iext_insert(ip, *idx, 1, new, state);
 
-		xfs_iext_insert(ip, idx + 1, 1, new, state);
-		ip->i_df.if_lastex = idx + 1;
 		ip->i_d.di_nextents++;
 		if (cur == NULL)
 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
@@ -1568,10 +1541,10 @@ xfs_bmap_add_extent_unwritten_real(
 		 * newext.  Contiguity is impossible here.
 		 * One extent becomes three extents.
 		 */
-		trace_xfs_bmap_pre_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
 		xfs_bmbt_set_blockcount(ep,
 			new->br_startoff - PREV.br_startoff);
-		trace_xfs_bmap_post_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 
 		r[0] = *new;
 		r[1].br_startoff = new_endoff;
@@ -1579,8 +1552,10 @@ xfs_bmap_add_extent_unwritten_real(
 			PREV.br_startoff + PREV.br_blockcount - new_endoff;
 		r[1].br_startblock = new->br_startblock + new->br_blockcount;
 		r[1].br_state = oldext;
-		xfs_iext_insert(ip, idx + 1, 2, &r[0], state);
-		ip->i_df.if_lastex = idx + 1;
+
+		++*idx;
+		xfs_iext_insert(ip, *idx, 2, &r[0], state);
+
 		ip->i_d.di_nextents += 2;
 		if (cur == NULL)
 			rval = XFS_ILOG_CORE | XFS_ILOG_DEXT;
@@ -1650,12 +1625,10 @@ done:
 STATIC int				/* error */
 xfs_bmap_add_extent_hole_delay(
 	xfs_inode_t		*ip,	/* incore inode pointer */
-	xfs_extnum_t		idx,	/* extent number to update/insert */
+	xfs_extnum_t		*idx,	/* extent number to update/insert */
 	xfs_bmbt_irec_t		*new,	/* new data to add to file extents */
-	int			*logflagsp, /* inode logging flags */
-	int			rsvd)		/* OK to allocate reserved blocks */
+	int			*logflagsp) /* inode logging flags */
 {
-	xfs_bmbt_rec_host_t	*ep;	/* extent record for idx */
 	xfs_ifork_t		*ifp;	/* inode fork pointer */
 	xfs_bmbt_irec_t		left;	/* left neighbor extent entry */
 	xfs_filblks_t		newlen=0;	/* new indirect size */
@@ -1665,16 +1638,15 @@ xfs_bmap_add_extent_hole_delay(
 	xfs_filblks_t		temp=0;	/* temp for indirect calculations */
 
 	ifp = XFS_IFORK_PTR(ip, XFS_DATA_FORK);
-	ep = xfs_iext_get_ext(ifp, idx);
 	state = 0;
 	ASSERT(isnullstartblock(new->br_startblock));
 
 	/*
 	 * Check and set flags if this segment has a left neighbor
 	 */
-	if (idx > 0) {
+	if (*idx > 0) {
 		state |= BMAP_LEFT_VALID;
-		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, idx - 1), &left);
+		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, *idx - 1), &left);
 
 		if (isnullstartblock(left.br_startblock))
 			state |= BMAP_LEFT_DELAY;
@@ -1684,9 +1656,9 @@ xfs_bmap_add_extent_hole_delay(
 	 * Check and set flags if the current (right) segment exists.
 	 * If it doesn't exist, we're converting the hole at end-of-file.
 	 */
-	if (idx < ip->i_df.if_bytes / (uint)sizeof(xfs_bmbt_rec_t)) {
+	if (*idx < ip->i_df.if_bytes / (uint)sizeof(xfs_bmbt_rec_t)) {
 		state |= BMAP_RIGHT_VALID;
-		xfs_bmbt_get_all(ep, &right);
+		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, *idx), &right);
 
 		if (isnullstartblock(right.br_startblock))
 			state |= BMAP_RIGHT_DELAY;
@@ -1719,21 +1691,21 @@ xfs_bmap_add_extent_hole_delay(
 		 * on the left and on the right.
 		 * Merge all three into a single extent record.
 		 */
+		--*idx;
 		temp = left.br_blockcount + new->br_blockcount +
 			right.br_blockcount;
 
-		trace_xfs_bmap_pre_update(ip, idx - 1, state, _THIS_IP_);
-		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, idx - 1), temp);
+		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
+		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, *idx), temp);
 		oldlen = startblockval(left.br_startblock) +
 			startblockval(new->br_startblock) +
 			startblockval(right.br_startblock);
 		newlen = xfs_bmap_worst_indlen(ip, temp);
-		xfs_bmbt_set_startblock(xfs_iext_get_ext(ifp, idx - 1),
+		xfs_bmbt_set_startblock(xfs_iext_get_ext(ifp, *idx),
 			nullstartblock((int)newlen));
-		trace_xfs_bmap_post_update(ip, idx - 1, state, _THIS_IP_);
+		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 
-		xfs_iext_remove(ip, idx, 1, state);
-		ip->i_df.if_lastex = idx - 1;
+		xfs_iext_remove(ip, *idx + 1, 1, state);
 		break;
 
 	case BMAP_LEFT_CONTIG:
@@ -1742,17 +1714,17 @@ xfs_bmap_add_extent_hole_delay(
 		 * on the left.
 		 * Merge the new allocation with the left neighbor.
 		 */
+		--*idx;
 		temp = left.br_blockcount + new->br_blockcount;
-		trace_xfs_bmap_pre_update(ip, idx - 1, state, _THIS_IP_);
-		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, idx - 1), temp);
+
+		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
+		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, *idx), temp);
 		oldlen = startblockval(left.br_startblock) +
 			startblockval(new->br_startblock);
 		newlen = xfs_bmap_worst_indlen(ip, temp);
-		xfs_bmbt_set_startblock(xfs_iext_get_ext(ifp, idx - 1),
+		xfs_bmbt_set_startblock(xfs_iext_get_ext(ifp, *idx),
 			nullstartblock((int)newlen));
-		trace_xfs_bmap_post_update(ip, idx - 1, state, _THIS_IP_);
-
-		ip->i_df.if_lastex = idx - 1;
+		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 		break;
 
 	case BMAP_RIGHT_CONTIG:
@@ -1761,16 +1733,15 @@ xfs_bmap_add_extent_hole_delay(
 		 * on the right.
 		 * Merge the new allocation with the right neighbor.
 		 */
-		trace_xfs_bmap_pre_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
 		temp = new->br_blockcount + right.br_blockcount;
 		oldlen = startblockval(new->br_startblock) +
 			startblockval(right.br_startblock);
 		newlen = xfs_bmap_worst_indlen(ip, temp);
-		xfs_bmbt_set_allf(ep, new->br_startoff,
+		xfs_bmbt_set_allf(xfs_iext_get_ext(ifp, *idx),
+			new->br_startoff,
 			nullstartblock((int)newlen), temp, right.br_state);
-		trace_xfs_bmap_post_update(ip, idx, state, _THIS_IP_);
-
-		ip->i_df.if_lastex = idx;
+		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 		break;
 
 	case 0:
@@ -1780,14 +1751,13 @@ xfs_bmap_add_extent_hole_delay(
 		 * Insert a new entry.
 		 */
 		oldlen = newlen = 0;
-		xfs_iext_insert(ip, idx, 1, new, state);
-		ip->i_df.if_lastex = idx;
+		xfs_iext_insert(ip, *idx, 1, new, state);
 		break;
 	}
 	if (oldlen != newlen) {
 		ASSERT(oldlen > newlen);
 		xfs_icsb_modify_counters(ip->i_mount, XFS_SBS_FDBLOCKS,
-			(int64_t)(oldlen - newlen), rsvd);
+			(int64_t)(oldlen - newlen), 0);
 		/*
 		 * Nothing to do for disk quota accounting here.
 		 */
@@ -1803,13 +1773,12 @@ xfs_bmap_add_extent_hole_delay(
 STATIC int				/* error */
 xfs_bmap_add_extent_hole_real(
 	xfs_inode_t		*ip,	/* incore inode pointer */
-	xfs_extnum_t		idx,	/* extent number to update/insert */
+	xfs_extnum_t		*idx,	/* extent number to update/insert */
 	xfs_btree_cur_t		*cur,	/* if null, not a btree */
 	xfs_bmbt_irec_t		*new,	/* new data to add to file extents */
 	int			*logflagsp, /* inode logging flags */
 	int			whichfork) /* data or attr fork */
 {
-	xfs_bmbt_rec_host_t	*ep;	/* pointer to extent entry ins. point */
 	int			error;	/* error return value */
 	int			i;	/* temp state */
 	xfs_ifork_t		*ifp;	/* inode fork pointer */
@@ -1819,8 +1788,7 @@ xfs_bmap_add_extent_hole_real(
 	int			state;	/* state bits, accessed thru macros */
 
 	ifp = XFS_IFORK_PTR(ip, whichfork);
-	ASSERT(idx <= ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t));
-	ep = xfs_iext_get_ext(ifp, idx);
+	ASSERT(*idx <= ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t));
 	state = 0;
 
 	if (whichfork == XFS_ATTR_FORK)
@@ -1829,9 +1797,9 @@ xfs_bmap_add_extent_hole_real(
 	/*
 	 * Check and set flags if this segment has a left neighbor.
 	 */
-	if (idx > 0) {
+	if (*idx > 0) {
 		state |= BMAP_LEFT_VALID;
-		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, idx - 1), &left);
+		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, *idx - 1), &left);
 		if (isnullstartblock(left.br_startblock))
 			state |= BMAP_LEFT_DELAY;
 	}
@@ -1840,9 +1808,9 @@ xfs_bmap_add_extent_hole_real(
 	 * Check and set flags if this segment has a current value.
 	 * Not true if we're inserting into the "hole" at eof.
 	 */
-	if (idx < ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t)) {
+	if (*idx < ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t)) {
 		state |= BMAP_RIGHT_VALID;
-		xfs_bmbt_get_all(ep, &right);
+		xfs_bmbt_get_all(xfs_iext_get_ext(ifp, *idx), &right);
 		if (isnullstartblock(right.br_startblock))
 			state |= BMAP_RIGHT_DELAY;
 	}
@@ -1879,14 +1847,15 @@ xfs_bmap_add_extent_hole_real(
 		 * left and on the right.
 		 * Merge all three into a single extent record.
 		 */
-		trace_xfs_bmap_pre_update(ip, idx - 1, state, _THIS_IP_);
-		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, idx - 1),
+		--*idx;
+		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
+		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, *idx),
 			left.br_blockcount + new->br_blockcount +
 			right.br_blockcount);
-		trace_xfs_bmap_post_update(ip, idx - 1, state, _THIS_IP_);
+		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
+
+		xfs_iext_remove(ip, *idx + 1, 1, state);
 
-		xfs_iext_remove(ip, idx, 1, state);
-		ifp->if_lastex = idx - 1;
 		XFS_IFORK_NEXT_SET(ip, whichfork,
 			XFS_IFORK_NEXTENTS(ip, whichfork) - 1);
 		if (cur == NULL) {
@@ -1921,12 +1890,12 @@ xfs_bmap_add_extent_hole_real(
 		 * on the left.
 		 * Merge the new allocation with the left neighbor.
 		 */
-		trace_xfs_bmap_pre_update(ip, idx - 1, state, _THIS_IP_);
-		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, idx - 1),
+		--*idx;
+		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
+		xfs_bmbt_set_blockcount(xfs_iext_get_ext(ifp, *idx),
 			left.br_blockcount + new->br_blockcount);
-		trace_xfs_bmap_post_update(ip, idx - 1, state, _THIS_IP_);
+		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 
-		ifp->if_lastex = idx - 1;
 		if (cur == NULL) {
 			rval = xfs_ilog_fext(whichfork);
 		} else {
@@ -1952,13 +1921,13 @@ xfs_bmap_add_extent_hole_real(
 		 * on the right.
 		 * Merge the new allocation with the right neighbor.
 		 */
-		trace_xfs_bmap_pre_update(ip, idx, state, _THIS_IP_);
-		xfs_bmbt_set_allf(ep, new->br_startoff, new->br_startblock,
+		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
+		xfs_bmbt_set_allf(xfs_iext_get_ext(ifp, *idx),
+			new->br_startoff, new->br_startblock,
 			new->br_blockcount + right.br_blockcount,
 			right.br_state);
-		trace_xfs_bmap_post_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 
-		ifp->if_lastex = idx;
 		if (cur == NULL) {
 			rval = xfs_ilog_fext(whichfork);
 		} else {
@@ -1984,8 +1953,7 @@ xfs_bmap_add_extent_hole_real(
 		 * real allocation.
 		 * Insert a new entry.
 		 */
-		xfs_iext_insert(ip, idx, 1, new, state);
-		ifp->if_lastex = idx;
+		xfs_iext_insert(ip, *idx, 1, new, state);
 		XFS_IFORK_NEXT_SET(ip, whichfork,
 			XFS_IFORK_NEXTENTS(ip, whichfork) + 1);
 		if (cur == NULL) {
@@ -2833,13 +2801,12 @@ STATIC int				/* error */
 xfs_bmap_del_extent(
 	xfs_inode_t		*ip,	/* incore inode pointer */
 	xfs_trans_t		*tp,	/* current transaction pointer */
-	xfs_extnum_t		idx,	/* extent number to update/delete */
+	xfs_extnum_t		*idx,	/* extent number to update/delete */
 	xfs_bmap_free_t		*flist,	/* list of extents to be freed */
 	xfs_btree_cur_t		*cur,	/* if null, not a btree */
 	xfs_bmbt_irec_t		*del,	/* data to remove from extents */
 	int			*logflagsp, /* inode logging flags */
-	int			whichfork, /* data or attr fork */
-	int			rsvd)	/* OK to allocate reserved blocks */
+	int			whichfork) /* data or attr fork */
 {
 	xfs_filblks_t		da_new;	/* new delay-alloc indirect blocks */
 	xfs_filblks_t		da_old;	/* old delay-alloc indirect blocks */
@@ -2870,10 +2837,10 @@ xfs_bmap_del_extent(
 
 	mp = ip->i_mount;
 	ifp = XFS_IFORK_PTR(ip, whichfork);
-	ASSERT((idx >= 0) && (idx < ifp->if_bytes /
+	ASSERT((*idx >= 0) && (*idx < ifp->if_bytes /
 		(uint)sizeof(xfs_bmbt_rec_t)));
 	ASSERT(del->br_blockcount > 0);
-	ep = xfs_iext_get_ext(ifp, idx);
+	ep = xfs_iext_get_ext(ifp, *idx);
 	xfs_bmbt_get_all(ep, &got);
 	ASSERT(got.br_startoff <= del->br_startoff);
 	del_endoff = del->br_startoff + del->br_blockcount;
@@ -2947,11 +2914,12 @@ xfs_bmap_del_extent(
 		/*
 		 * Matches the whole extent.  Delete the entry.
 		 */
-		xfs_iext_remove(ip, idx, 1,
+		xfs_iext_remove(ip, *idx, 1,
 				whichfork == XFS_ATTR_FORK ? BMAP_ATTRFORK : 0);
-		ifp->if_lastex = idx;
+		--*idx;
 		if (delay)
 			break;
+
 		XFS_IFORK_NEXT_SET(ip, whichfork,
 			XFS_IFORK_NEXTENTS(ip, whichfork) - 1);
 		flags |= XFS_ILOG_CORE;
@@ -2968,21 +2936,20 @@ xfs_bmap_del_extent(
 		/*
 		 * Deleting the first part of the extent.
 		 */
-		trace_xfs_bmap_pre_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
 		xfs_bmbt_set_startoff(ep, del_endoff);
 		temp = got.br_blockcount - del->br_blockcount;
 		xfs_bmbt_set_blockcount(ep, temp);
-		ifp->if_lastex = idx;
 		if (delay) {
 			temp = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip, temp),
 				da_old);
 			xfs_bmbt_set_startblock(ep, nullstartblock((int)temp));
-			trace_xfs_bmap_post_update(ip, idx, state, _THIS_IP_);
+			trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 			da_new = temp;
 			break;
 		}
 		xfs_bmbt_set_startblock(ep, del_endblock);
-		trace_xfs_bmap_post_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 		if (!cur) {
 			flags |= xfs_ilog_fext(whichfork);
 			break;
@@ -2998,18 +2965,17 @@ xfs_bmap_del_extent(
 		 * Deleting the last part of the extent.
 		 */
 		temp = got.br_blockcount - del->br_blockcount;
-		trace_xfs_bmap_pre_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
 		xfs_bmbt_set_blockcount(ep, temp);
-		ifp->if_lastex = idx;
 		if (delay) {
 			temp = XFS_FILBLKS_MIN(xfs_bmap_worst_indlen(ip, temp),
 				da_old);
 			xfs_bmbt_set_startblock(ep, nullstartblock((int)temp));
-			trace_xfs_bmap_post_update(ip, idx, state, _THIS_IP_);
+			trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 			da_new = temp;
 			break;
 		}
-		trace_xfs_bmap_post_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
 		if (!cur) {
 			flags |= xfs_ilog_fext(whichfork);
 			break;
@@ -3026,7 +2992,7 @@ xfs_bmap_del_extent(
 		 * Deleting the middle of the extent.
 		 */
 		temp = del->br_startoff - got.br_startoff;
-		trace_xfs_bmap_pre_update(ip, idx, state, _THIS_IP_);
+		trace_xfs_bmap_pre_update(ip, *idx, state, _THIS_IP_);
 		xfs_bmbt_set_blockcount(ep, temp);
 		new.br_startoff = del_endoff;
 		temp2 = got_endoff - del_endoff;
@@ -3113,9 +3079,9 @@ xfs_bmap_del_extent(
 				}
 			}
 		}
-		trace_xfs_bmap_post_update(ip, idx, state, _THIS_IP_);
-		xfs_iext_insert(ip, idx + 1, 1, &new, state);
-		ifp->if_lastex = idx + 1;
+		trace_xfs_bmap_post_update(ip, *idx, state, _THIS_IP_);
+		xfs_iext_insert(ip, *idx + 1, 1, &new, state);
+		++*idx;
 		break;
 	}
 	/*
@@ -3142,7 +3108,7 @@ xfs_bmap_del_extent(
 	ASSERT(da_old >= da_new);
 	if (da_old > da_new) {
 		xfs_icsb_modify_counters(mp, XFS_SBS_FDBLOCKS,
-			(int64_t)(da_old - da_new), rsvd);
+			(int64_t)(da_old - da_new), 0);
 	}
 done:
 	*logflagsp = flags;
@@ -4562,29 +4528,24 @@ xfs_bmapi(
 				if (rt) {
 					error = xfs_mod_incore_sb(mp,
 							XFS_SBS_FREXTENTS,
-							-((int64_t)extsz), (flags &
-							XFS_BMAPI_RSVBLOCKS));
+							-((int64_t)extsz), 0);
 				} else {
 					error = xfs_icsb_modify_counters(mp,
 							XFS_SBS_FDBLOCKS,
-							-((int64_t)alen), (flags &
-							XFS_BMAPI_RSVBLOCKS));
+							-((int64_t)alen), 0);
 				}
 				if (!error) {
 					error = xfs_icsb_modify_counters(mp,
 							XFS_SBS_FDBLOCKS,
-							-((int64_t)indlen), (flags &
-							XFS_BMAPI_RSVBLOCKS));
+							-((int64_t)indlen), 0);
 					if (error && rt)
 						xfs_mod_incore_sb(mp,
 							XFS_SBS_FREXTENTS,
-							(int64_t)extsz, (flags &
-							XFS_BMAPI_RSVBLOCKS));
+							(int64_t)extsz, 0);
 					else if (error)
 						xfs_icsb_modify_counters(mp,
 							XFS_SBS_FDBLOCKS,
-							(int64_t)alen, (flags &
-							XFS_BMAPI_RSVBLOCKS));
+							(int64_t)alen, 0);
 				}
 
 				if (error) {
@@ -4701,13 +4662,12 @@ xfs_bmapi(
 				if (!wasdelay && (flags & XFS_BMAPI_PREALLOC))
 					got.br_state = XFS_EXT_UNWRITTEN;
 			}
-			error = xfs_bmap_add_extent(ip, lastx, &cur, &got,
+			error = xfs_bmap_add_extent(ip, &lastx, &cur, &got,
 				firstblock, flist, &tmp_logflags,
-				whichfork, (flags & XFS_BMAPI_RSVBLOCKS));
+				whichfork);
 			logflags |= tmp_logflags;
 			if (error)
 				goto error0;
-			lastx = ifp->if_lastex;
 			ep = xfs_iext_get_ext(ifp, lastx);
 			nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
 			xfs_bmbt_get_all(ep, &got);
@@ -4803,13 +4763,12 @@ xfs_bmapi(
 			mval->br_state = (mval->br_state == XFS_EXT_UNWRITTEN)
 						? XFS_EXT_NORM
 						: XFS_EXT_UNWRITTEN;
-			error = xfs_bmap_add_extent(ip, lastx, &cur, mval,
+			error = xfs_bmap_add_extent(ip, &lastx, &cur, mval,
 				firstblock, flist, &tmp_logflags,
-				whichfork, (flags & XFS_BMAPI_RSVBLOCKS));
+				whichfork);
 			logflags |= tmp_logflags;
 			if (error)
 				goto error0;
-			lastx = ifp->if_lastex;
 			ep = xfs_iext_get_ext(ifp, lastx);
 			nextents = ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t);
 			xfs_bmbt_get_all(ep, &got);
@@ -4868,14 +4827,14 @@ xfs_bmapi(
 		/*
 		 * Else go on to the next record.
 		 */
-		ep = xfs_iext_get_ext(ifp, ++lastx);
 		prev = got;
-		if (lastx >= nextents)
-			eof = 1;
-		else
+		if (++lastx < nextents) {
+			ep = xfs_iext_get_ext(ifp, lastx);
 			xfs_bmbt_get_all(ep, &got);
+		} else {
+			eof = 1;
+		}
 	}
-	ifp->if_lastex = lastx;
 	*nmap = n;
 	/*
 	 * Transform from btree to extents, give it cur.
@@ -4984,7 +4943,6 @@ xfs_bmapi_single(
 	ASSERT(!isnullstartblock(got.br_startblock));
 	ASSERT(bno < got.br_startoff + got.br_blockcount);
 	*fsb = got.br_startblock + (bno - got.br_startoff);
-	ifp->if_lastex = lastx;
 	return 0;
 }
 
@@ -5026,7 +4984,6 @@ xfs_bunmapi(
 	int			tmp_logflags;	/* partial logging flags */
 	int			wasdel;		/* was a delayed alloc extent */
 	int			whichfork;	/* data or attribute fork */
-	int			rsvd;		/* OK to allocate reserved blocks */
 	xfs_fsblock_t		sum;
 
 	trace_xfs_bunmap(ip, bno, len, flags, _RET_IP_);
@@ -5044,7 +5001,7 @@ xfs_bunmapi(
 	mp = ip->i_mount;
 	if (XFS_FORCED_SHUTDOWN(mp))
 		return XFS_ERROR(EIO);
-	rsvd = (flags & XFS_BMAPI_RSVBLOCKS) != 0;
+
 	ASSERT(len > 0);
 	ASSERT(nexts >= 0);
 	ASSERT(ifp->if_ext_max ==
@@ -5160,9 +5117,9 @@ xfs_bunmapi(
 				del.br_blockcount = mod;
 			}
 			del.br_state = XFS_EXT_UNWRITTEN;
-			error = xfs_bmap_add_extent(ip, lastx, &cur, &del,
+			error = xfs_bmap_add_extent(ip, &lastx, &cur, &del,
 				firstblock, flist, &logflags,
-				XFS_DATA_FORK, 0);
+				XFS_DATA_FORK);
 			if (error)
 				goto error0;
 			goto nodelete;
@@ -5188,9 +5145,12 @@ xfs_bunmapi(
 				 */
 				ASSERT(bno >= del.br_blockcount);
 				bno -= del.br_blockcount;
-				if (bno < got.br_startoff) {
-					if (--lastx >= 0)
-						xfs_bmbt_get_all(--ep, &got);
+				if (got.br_startoff > bno) {
+					if (--lastx >= 0) {
+						ep = xfs_iext_get_ext(ifp,
+								      lastx);
+						xfs_bmbt_get_all(ep, &got);
+					}
 				}
 				continue;
 			} else if (del.br_state == XFS_EXT_UNWRITTEN) {
@@ -5214,18 +5174,19 @@ xfs_bunmapi(
 					prev.br_startoff = start;
 				}
 				prev.br_state = XFS_EXT_UNWRITTEN;
-				error = xfs_bmap_add_extent(ip, lastx - 1, &cur,
+				lastx--;
+				error = xfs_bmap_add_extent(ip, &lastx, &cur,
 					&prev, firstblock, flist, &logflags,
-					XFS_DATA_FORK, 0);
+					XFS_DATA_FORK);
 				if (error)
 					goto error0;
 				goto nodelete;
 			} else {
 				ASSERT(del.br_state == XFS_EXT_NORM);
 				del.br_state = XFS_EXT_UNWRITTEN;
-				error = xfs_bmap_add_extent(ip, lastx, &cur,
+				error = xfs_bmap_add_extent(ip, &lastx, &cur,
 					&del, firstblock, flist, &logflags,
-					XFS_DATA_FORK, 0);
+					XFS_DATA_FORK);
 				if (error)
 					goto error0;
 				goto nodelete;
@@ -5240,13 +5201,13 @@ xfs_bunmapi(
 				rtexts = XFS_FSB_TO_B(mp, del.br_blockcount);
 				do_div(rtexts, mp->m_sb.sb_rextsize);
 				xfs_mod_incore_sb(mp, XFS_SBS_FREXTENTS,
-						(int64_t)rtexts, rsvd);
+						(int64_t)rtexts, 0);
 				(void)xfs_trans_reserve_quota_nblks(NULL,
 					ip, -((long)del.br_blockcount), 0,
 					XFS_QMOPT_RES_RTBLKS);
 			} else {
 				xfs_icsb_modify_counters(mp, XFS_SBS_FDBLOCKS,
-						(int64_t)del.br_blockcount, rsvd);
+						(int64_t)del.br_blockcount, 0);
 				(void)xfs_trans_reserve_quota_nblks(NULL,
 					ip, -((long)del.br_blockcount), 0,
 					XFS_QMOPT_RES_REGBLKS);
@@ -5277,31 +5238,29 @@ xfs_bunmapi(
 			error = XFS_ERROR(ENOSPC);
 			goto error0;
 		}
-		error = xfs_bmap_del_extent(ip, tp, lastx, flist, cur, &del,
-				&tmp_logflags, whichfork, rsvd);
+		error = xfs_bmap_del_extent(ip, tp, &lastx, flist, cur, &del,
+				&tmp_logflags, whichfork);
 		logflags |= tmp_logflags;
 		if (error)
 			goto error0;
 		bno = del.br_startoff - 1;
 nodelete:
-		lastx = ifp->if_lastex;
 		/*
 		 * If not done go on to the next (previous) record.
-		 * Reset ep in case the extents array was re-alloced.
 		 */
-		ep = xfs_iext_get_ext(ifp, lastx);
 		if (bno != (xfs_fileoff_t)-1 && bno >= start) {
-			if (lastx >= XFS_IFORK_NEXTENTS(ip, whichfork) ||
-			    xfs_bmbt_get_startoff(ep) > bno) {
-				if (--lastx >= 0)
-					ep = xfs_iext_get_ext(ifp, lastx);
-			}
-			if (lastx >= 0)
+			if (lastx >= 0) {
+				ep = xfs_iext_get_ext(ifp, lastx);
+				if (xfs_bmbt_get_startoff(ep) > bno) {
+					if (--lastx >= 0)
+						ep = xfs_iext_get_ext(ifp,
+								      lastx);
+				}
 				xfs_bmbt_get_all(ep, &got);
+			}
 			extno++;
 		}
 	}
-	ifp->if_lastex = lastx;
 	*done = bno == (xfs_fileoff_t)-1 || bno < start || lastx < 0;
 	ASSERT(ifp->if_ext_max ==
 	       XFS_IFORK_SIZE(ip, whichfork) / (uint)sizeof(xfs_bmbt_rec_t));
diff --git a/fs/xfs/xfs_bmap.h b/fs/xfs/xfs_bmap.h
index 3651191daea1..c62234bde053 100644
--- a/fs/xfs/xfs_bmap.h
+++ b/fs/xfs/xfs_bmap.h
@@ -69,7 +69,6 @@ typedef	struct xfs_bmap_free
 #define XFS_BMAPI_ENTIRE	0x004	/* return entire extent, not trimmed */
 #define XFS_BMAPI_METADATA	0x008	/* mapping metadata not user data */
 #define XFS_BMAPI_ATTRFORK	0x010	/* use attribute fork not data */
-#define XFS_BMAPI_RSVBLOCKS	0x020	/* OK to alloc. reserved data blocks */
 #define	XFS_BMAPI_PREALLOC	0x040	/* preallocation op: unwritten space */
 #define	XFS_BMAPI_IGSTATE	0x080	/* Ignore state - */
 					/* combine contig. space */
@@ -87,7 +86,6 @@ typedef	struct xfs_bmap_free
 	{ XFS_BMAPI_ENTIRE,	"ENTIRE" }, \
 	{ XFS_BMAPI_METADATA,	"METADATA" }, \
 	{ XFS_BMAPI_ATTRFORK,	"ATTRFORK" }, \
-	{ XFS_BMAPI_RSVBLOCKS,	"RSVBLOCKS" }, \
 	{ XFS_BMAPI_PREALLOC,	"PREALLOC" }, \
 	{ XFS_BMAPI_IGSTATE,	"IGSTATE" }, \
 	{ XFS_BMAPI_CONTIG,	"CONTIG" }, \
diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c
index c8e3349c287c..a098a20ca63e 100644
--- a/fs/xfs/xfs_inode.c
+++ b/fs/xfs/xfs_inode.c
@@ -920,7 +920,6 @@ xfs_iread_extents(
 	/*
 	 * We know that the size is valid (it's checked in iformat_btree)
 	 */
-	ifp->if_lastex = NULLEXTNUM;
 	ifp->if_bytes = ifp->if_real_bytes = 0;
 	ifp->if_flags |= XFS_IFEXTENTS;
 	xfs_iext_add(ifp, 0, nextents);
@@ -2558,12 +2557,9 @@ xfs_iflush_fork(
 	case XFS_DINODE_FMT_EXTENTS:
 		ASSERT((ifp->if_flags & XFS_IFEXTENTS) ||
 		       !(iip->ili_format.ilf_fields & extflag[whichfork]));
-		ASSERT((xfs_iext_get_ext(ifp, 0) != NULL) ||
-			(ifp->if_bytes == 0));
-		ASSERT((xfs_iext_get_ext(ifp, 0) == NULL) ||
-			(ifp->if_bytes > 0));
 		if ((iip->ili_format.ilf_fields & extflag[whichfork]) &&
 		    (ifp->if_bytes > 0)) {
+			ASSERT(xfs_iext_get_ext(ifp, 0));
 			ASSERT(XFS_IFORK_NEXTENTS(ip, whichfork) > 0);
 			(void)xfs_iextents_copy(ip, (xfs_bmbt_rec_t *)cp,
 				whichfork);
@@ -3112,6 +3108,8 @@ xfs_iext_get_ext(
 	xfs_extnum_t	idx)		/* index of target extent */
 {
 	ASSERT(idx >= 0);
+	ASSERT(idx < ifp->if_bytes / sizeof(xfs_bmbt_rec_t));
+
 	if ((ifp->if_flags & XFS_IFEXTIREC) && (idx == 0)) {
 		return ifp->if_u1.if_ext_irec->er_extbuf;
 	} else if (ifp->if_flags & XFS_IFEXTIREC) {
@@ -3191,7 +3189,6 @@ xfs_iext_add(
 		}
 		ifp->if_u1.if_extents = ifp->if_u2.if_inline_ext;
 		ifp->if_real_bytes = 0;
-		ifp->if_lastex = nextents + ext_diff;
 	}
 	/*
 	 * Otherwise use a linear (direct) extent list.
@@ -3886,8 +3883,10 @@ xfs_iext_idx_to_irec(
 	xfs_extnum_t	page_idx = *idxp; /* extent index in target list */
 
 	ASSERT(ifp->if_flags & XFS_IFEXTIREC);
-	ASSERT(page_idx >= 0 && page_idx <=
-		ifp->if_bytes / (uint)sizeof(xfs_bmbt_rec_t));
+	ASSERT(page_idx >= 0);
+	ASSERT(page_idx <= ifp->if_bytes / sizeof(xfs_bmbt_rec_t));
+	ASSERT(page_idx < ifp->if_bytes / sizeof(xfs_bmbt_rec_t) || realloc);
+
 	nlists = ifp->if_real_bytes / XFS_IEXT_BUFSZ;
 	erp_idx = 0;
 	low = 0;
diff --git a/fs/xfs/xfs_inode.h b/fs/xfs/xfs_inode.h
index ff4e2a30227d..3ae6d58e5473 100644
--- a/fs/xfs/xfs_inode.h
+++ b/fs/xfs/xfs_inode.h
@@ -67,7 +67,6 @@ typedef struct xfs_ifork {
 	short			if_broot_bytes;	/* bytes allocated for root */
 	unsigned char		if_flags;	/* per-fork flags */
 	unsigned char		if_ext_max;	/* max # of extent records */
-	xfs_extnum_t		if_lastex;	/* last if_extents used */
 	union {
 		xfs_bmbt_rec_host_t *if_extents;/* linear map file exts */
 		xfs_ext_irec_t	*if_ext_irec;	/* irec map file exts */
diff --git a/fs/xfs/xfs_log_cil.c b/fs/xfs/xfs_log_cil.c
index 7d56e88a3f0e..c7755d5a5fbe 100644
--- a/fs/xfs/xfs_log_cil.c
+++ b/fs/xfs/xfs_log_cil.c
@@ -29,6 +29,7 @@
 #include "xfs_mount.h"
 #include "xfs_error.h"
 #include "xfs_alloc.h"
+#include "xfs_discard.h"
 
 /*
  * Perform initial CIL structure initialisation. If the CIL is not
@@ -361,18 +362,28 @@ xlog_cil_committed(
 	int	abort)
 {
 	struct xfs_cil_ctx	*ctx = args;
+	struct xfs_mount	*mp = ctx->cil->xc_log->l_mp;
 
 	xfs_trans_committed_bulk(ctx->cil->xc_log->l_ailp, ctx->lv_chain,
 					ctx->start_lsn, abort);
 
 	xfs_alloc_busy_sort(&ctx->busy_extents);
-	xfs_alloc_busy_clear(ctx->cil->xc_log->l_mp, &ctx->busy_extents);
+	xfs_alloc_busy_clear(mp, &ctx->busy_extents,
+			     (mp->m_flags & XFS_MOUNT_DISCARD) && !abort);
 
 	spin_lock(&ctx->cil->xc_cil_lock);
 	list_del(&ctx->committing);
 	spin_unlock(&ctx->cil->xc_cil_lock);
 
 	xlog_cil_free_logvec(ctx->lv_chain);
+
+	if (!list_empty(&ctx->busy_extents)) {
+		ASSERT(mp->m_flags & XFS_MOUNT_DISCARD);
+
+		xfs_discard_extents(mp, &ctx->busy_extents);
+		xfs_alloc_busy_clear(mp, &ctx->busy_extents, false);
+	}
+
 	kmem_free(ctx);
 }
 
diff --git a/fs/xfs/xfs_mount.h b/fs/xfs/xfs_mount.h
index 19af0ab0d0c6..3d68bb267c5f 100644
--- a/fs/xfs/xfs_mount.h
+++ b/fs/xfs/xfs_mount.h
@@ -224,6 +224,7 @@ typedef struct xfs_mount {
 #define XFS_MOUNT_FS_SHUTDOWN	(1ULL << 4)	/* atomic stop of all filesystem
 						   operations, typically for
 						   disk errors in metadata */
+#define XFS_MOUNT_DISCARD	(1ULL << 5)	/* discard unused blocks */
 #define XFS_MOUNT_RETERR	(1ULL << 6)     /* return alignment errors to
 						   user */
 #define XFS_MOUNT_NOALIGN	(1ULL << 7)	/* turn off stripe alignment
diff --git a/fs/xfs/xfs_trans.c b/fs/xfs/xfs_trans.c
index d1f24858ccc4..7c7bc2b786bd 100644
--- a/fs/xfs/xfs_trans.c
+++ b/fs/xfs/xfs_trans.c
@@ -609,7 +609,7 @@ xfs_trans_free(
 	struct xfs_trans	*tp)
 {
 	xfs_alloc_busy_sort(&tp->t_busy);
-	xfs_alloc_busy_clear(tp->t_mountp, &tp->t_busy);
+	xfs_alloc_busy_clear(tp->t_mountp, &tp->t_busy, false);
 
 	atomic_dec(&tp->t_mountp->m_active_trans);
 	xfs_trans_free_dqinfo(tp);