diff --git a/fs/lustre/include/cl_object.h b/fs/lustre/include/cl_object.h
index c717d03..0f28cfe 100644
--- a/fs/lustre/include/cl_object.h
+++ b/fs/lustre/include/cl_object.h
@@ -1788,8 +1788,8 @@ struct cl_io {
 	enum cl_io_state	ci_state;
 	/** main object this io is against. Immutable after creation. */
 	struct cl_object	*ci_obj;
-	/** one AIO request might be split in cl_io_loop */
-	struct cl_dio_aio	*ci_aio;
+	/** top level dio_aio */
+	struct cl_dio_aio	*ci_dio_aio;
 	/**
 	 * Upper layer io, of which this io is a part of. Immutable after
 	 * creation.
@@ -2532,11 +2532,12 @@ void cl_req_attr_set(const struct lu_env *env, struct cl_object *obj,
 
 struct cl_sync_io;
 struct cl_dio_aio;
+struct cl_sub_dio;
 
 typedef void (cl_sync_io_end_t)(const struct lu_env *, struct cl_sync_io *);
 
-void cl_sync_io_init_notify(struct cl_sync_io *anchor, int nr,
-			    struct cl_dio_aio *aio, cl_sync_io_end_t *end);
+void cl_sync_io_init_notify(struct cl_sync_io *anchor, int nr, void *dio_aio,
+			    cl_sync_io_end_t *end);
 
 int cl_sync_io_wait(const struct lu_env *env, struct cl_sync_io *anchor,
 		    long timeout);
@@ -2544,9 +2545,12 @@ void cl_sync_io_note(const struct lu_env *env, struct cl_sync_io *anchor,
 		     int ioret);
 int cl_sync_io_wait_recycle(const struct lu_env *env, struct cl_sync_io *anchor,
 			    long timeout, int ioret);
-struct cl_dio_aio *cl_aio_alloc(struct kiocb *iocb, struct cl_object *obj,
-				struct cl_dio_aio *ll_aio);
-void cl_aio_free(const struct lu_env *env, struct cl_dio_aio *aio);
+struct cl_dio_aio *cl_dio_aio_alloc(struct kiocb *iocb, struct cl_object *obj,
+				    bool is_aio);
+struct cl_sub_dio *cl_sub_dio_alloc(struct cl_dio_aio *ll_aio, bool nofree);
+void cl_dio_aio_free(const struct lu_env *env, struct cl_dio_aio *aio,
+		     bool always_free);
+void cl_sub_dio_free(struct cl_sub_dio *sdio, bool nofree);
 
 static inline void cl_sync_io_init(struct cl_sync_io *anchor, int nr)
 {
@@ -2568,8 +2572,8 @@ struct cl_sync_io {
 	wait_queue_head_t	csi_waitq;
 	/** callback to invoke when this IO is finished */
 	cl_sync_io_end_t	*csi_end_io;
-	/** aio private data */
-	struct cl_dio_aio	*csi_aio;
+	/* private pointer for an associated DIO/AIO */
+	void			*csi_dio_aio;
 };
 
 
@@ -2587,17 +2591,26 @@ struct ll_dio_pages {
 	loff_t			ldp_file_offset;
 };
 
-/* To support Direct AIO */
+/* Top level struct used for AIO and DIO */
 struct cl_dio_aio {
 	struct cl_sync_io	cda_sync;
-	struct cl_page_list	cda_pages;
 	struct cl_object	*cda_obj;
 	struct kiocb		*cda_iocb;
 	ssize_t			cda_bytes;
-	struct cl_dio_aio	*cda_ll_aio;
-	struct ll_dio_pages	cda_dio_pages;
 	unsigned int		cda_no_aio_complete:1,
-				cda_no_aio_free:1;
+				cda_no_sub_free:1;
+};
+
+/* Sub-dio used for splitting DIO (and AIO, because AIO is DIO) according to
+ * the layout/striping, so we can do parallel submit of DIO RPCs
+ */
+struct cl_sub_dio {
+	struct cl_sync_io	csd_sync;
+	struct cl_page_list	csd_pages;
+	ssize_t			csd_bytes;
+	struct cl_dio_aio	*csd_ll_aio;
+	struct ll_dio_pages	csd_dio_pages;
+	unsigned int		csd_no_free:1;
 };
 
 void ll_release_user_pages(struct page **pages, int npages);
diff --git a/fs/lustre/llite/file.c b/fs/lustre/llite/file.c
index ac20d05..92e450f 100644
--- a/fs/lustre/llite/file.c
+++ b/fs/lustre/llite/file.c
@@ -1664,7 +1664,7 @@ static void ll_heat_add(struct inode *inode, enum cl_io_type iot,
 	unsigned int dio_lock = 0;
 	bool is_aio = false;
 	bool is_parallel_dio = false;
-	struct cl_dio_aio *ci_aio = NULL;
+	struct cl_dio_aio *ci_dio_aio = NULL;
 	size_t per_bytes;
 	bool partial_io = false;
 	size_t max_io_pages, max_cached_pages;
@@ -1694,9 +1694,10 @@ static void ll_heat_add(struct inode *inode, enum cl_io_type iot,
 		if (!ll_sbi_has_parallel_dio(sbi))
 			is_parallel_dio = false;
 
-		ci_aio = cl_aio_alloc(args->u.normal.via_iocb,
-				      ll_i2info(inode)->lli_clob, NULL);
-		if (!ci_aio) {
+		ci_dio_aio = cl_dio_aio_alloc(args->u.normal.via_iocb,
+					      ll_i2info(inode)->lli_clob,
+					      is_aio);
+		if (!ci_dio_aio) {
 			rc = -ENOMEM;
 			goto out;
 		}
@@ -1715,7 +1716,7 @@ static void ll_heat_add(struct inode *inode, enum cl_io_type iot,
 	partial_io = per_bytes < count;
 	io = vvp_env_thread_io(env);
 	ll_io_init(io, file, iot == CIT_WRITE, args);
-	io->ci_aio = ci_aio;
+	io->ci_dio_aio = ci_dio_aio;
 	io->ci_dio_lock = dio_lock;
 	io->ci_ndelay_tried = retried;
 	io->ci_parallel_dio = is_parallel_dio;
@@ -1762,12 +1763,8 @@ static void ll_heat_add(struct inode *inode, enum cl_io_type iot,
 		rc = io->ci_result;
 	}
 
-	/* N/B: parallel DIO may be disabled during i/o submission;
-	 * if that occurs, async RPCs are resolved before we get here, and this
-	 * wait call completes immediately.
-	 */
 	if (is_parallel_dio) {
-		struct cl_sync_io *anchor = &io->ci_aio->cda_sync;
+		struct cl_sync_io *anchor = &io->ci_dio_aio->cda_sync;
 
 		/* for dio, EIOCBQUEUED is an implementation detail,
 		 * and we don't return it to userspace
@@ -1775,6 +1772,11 @@ static void ll_heat_add(struct inode *inode, enum cl_io_type iot,
 		if (rc == -EIOCBQUEUED)
 			rc = 0;
 
+		/* N/B: parallel DIO may be disabled during i/o submission;
+		 * if that occurs, I/O shifts to sync, so it's all resolved
+		 * before we get here, and this wait call completes
+		 * immediately.
+		 */
 		rc2 = cl_sync_io_wait_recycle(env, anchor, 0, 0);
 		if (rc2 < 0)
 			rc = rc2;
@@ -1838,24 +1840,29 @@ static void ll_heat_add(struct inode *inode, enum cl_io_type iot,
 		goto restart;
 	}
 
-	if (io->ci_aio) {
+	if (io->ci_dio_aio) {
 		/*
 		 * VFS will call aio_complete() if no -EIOCBQUEUED
 		 * is returned for AIO, so we can not call aio_complete()
 		 * in our end_io().
+		 *
+		 * NB: This is safe because the atomic_dec_and_lock  in
+		 * cl_sync_io_init has implicit memory barriers, so this will
+		 * be seen by whichever thread completes the DIO/AIO, even if
+		 * it's not this one
 		 */
 		if (rc != -EIOCBQUEUED)
-			io->ci_aio->cda_no_aio_complete = 1;
+			io->ci_dio_aio->cda_no_aio_complete = 1;
 		/**
 		 * Drop one extra reference so that end_io() could be
 		 * called for this IO context, we could call it after
 		 * we make sure all AIO requests have been proceed.
 		 */
-		cl_sync_io_note(env, &io->ci_aio->cda_sync,
+		cl_sync_io_note(env, &io->ci_dio_aio->cda_sync,
 				rc == -EIOCBQUEUED ? 0 : rc);
 		if (!is_aio) {
-			cl_aio_free(env, io->ci_aio);
-			io->ci_aio = NULL;
+			cl_dio_aio_free(env, io->ci_dio_aio, true);
+			io->ci_dio_aio = NULL;
 		}
 	}
 
diff --git a/fs/lustre/llite/rw26.c b/fs/lustre/llite/rw26.c
index 7147f0f..0f9ab68 100644
--- a/fs/lustre/llite/rw26.c
+++ b/fs/lustre/llite/rw26.c
@@ -202,13 +202,13 @@ static unsigned long ll_iov_iter_alignment(struct iov_iter *i)
 
 static int
 ll_direct_rw_pages(const struct lu_env *env, struct cl_io *io, size_t size,
-		   int rw, struct inode *inode, struct cl_dio_aio *aio)
+		   int rw, struct inode *inode, struct cl_sub_dio *sdio)
 {
-	struct ll_dio_pages *pv = &aio->cda_dio_pages;
+	struct ll_dio_pages *pv = &sdio->csd_dio_pages;
 	struct cl_page *page;
 	struct cl_2queue *queue = &io->ci_queue;
 	struct cl_object *obj = io->ci_obj;
-	struct cl_sync_io *anchor = &aio->cda_sync;
+	struct cl_sync_io *anchor = &sdio->csd_sync;
 	loff_t offset = pv->ldp_file_offset;
 	int io_pages = 0;
 	size_t page_size = cl_page_size(obj);
@@ -268,7 +268,7 @@ static unsigned long ll_iov_iter_alignment(struct iov_iter *i)
 		smp_mb();
 		rc = cl_io_submit_rw(env, io, iot, queue);
 		if (rc == 0) {
-			cl_page_list_splice(&queue->c2_qout, &aio->cda_pages);
+			cl_page_list_splice(&queue->c2_qout, &sdio->csd_pages);
 		} else {
 			atomic_add(-queue->c2_qin.pl_nr,
 				   &anchor->csi_sync_nr);
@@ -307,13 +307,15 @@ static ssize_t ll_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
 	struct cl_io *io;
 	struct file *file = iocb->ki_filp;
 	struct inode *inode = file->f_mapping->host;
-	struct cl_dio_aio *ll_aio;
-	struct cl_dio_aio *ldp_aio;
+	struct cl_dio_aio *ll_dio_aio;
+	struct cl_sub_dio *ldp_aio;
 	size_t count = iov_iter_count(iter);
 	ssize_t tot_bytes = 0, result = 0;
 	loff_t file_offset = iocb->ki_pos;
 	int rw = iov_iter_rw(iter);
+	bool sync_submit = false;
 	struct vvp_io *vio;
+	ssize_t rc2;
 
 	/* Check EOF by ourselves */
 	if (rw == READ && file_offset >= i_size_read(inode))
@@ -343,9 +345,22 @@ static ssize_t ll_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
 	io = lcc->lcc_io;
 	LASSERT(io);
 
-	ll_aio = io->ci_aio;
-	LASSERT(ll_aio);
-	LASSERT(ll_aio->cda_iocb == iocb);
+	ll_dio_aio = io->ci_dio_aio;
+	LASSERT(ll_dio_aio);
+	LASSERT(ll_dio_aio->cda_iocb == iocb);
+
+	/* We cannot do parallel submission of sub-I/Os - for AIO or regular
+	 * DIO - unless lockless because it causes us to release the lock
+	 * early.
+	 *
+	 * There are also several circumstances in which we must disable
+	 * parallel DIO, so we check if it is enabled.
+	 *
+	 * The check for "is_sync_kiocb" excludes AIO, which does not need to
+	 * be disabled in these situations.
+	 */
+	if (io->ci_dio_lock || (is_sync_kiocb(iocb) && !io->ci_parallel_dio))
+		sync_submit = true;
 
 	while (iov_iter_count(iter)) {
 		struct ll_dio_pages *pvec;
@@ -360,22 +375,24 @@ static ssize_t ll_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
 				count = i_size_read(inode) - file_offset;
 		}
 
-		/* this aio is freed on completion from cl_sync_io_note, so we
-		 * do not need to directly free the memory here
+		/* if we are doing sync_submit, then we free this below,
+		 * otherwise it is freed on the final call to cl_sync_io_note
+		 * (either in this function or from a ptlrpcd daemon)
 		 */
-		ldp_aio = cl_aio_alloc(iocb, ll_i2info(inode)->lli_clob,
-				       ll_aio);
+		ldp_aio = cl_sub_dio_alloc(ll_dio_aio, sync_submit);
 		if (!ldp_aio) {
 			result = -ENOMEM;
 			goto out;
 		}
 
-		pvec = &ldp_aio->cda_dio_pages;
+		pvec = &ldp_aio->csd_dio_pages;
 
 		result = ll_get_user_pages(rw, iter, &pages,
 					   &pvec->ldp_count, count);
 		if (unlikely(result <= 0)) {
-			cl_sync_io_note(env, &ldp_aio->cda_sync, result);
+			cl_sync_io_note(env, &ldp_aio->csd_sync, result);
+			if (sync_submit)
+				cl_sub_dio_free(ldp_aio, true);
 			goto out;
 		}
 
@@ -388,8 +405,15 @@ static ssize_t ll_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
 		/* We've submitted pages and can now remove the extra
 		 * reference for that
 		 */
-		cl_sync_io_note(env, &ldp_aio->cda_sync, result);
-
+		cl_sync_io_note(env, &ldp_aio->csd_sync, result);
+
+		if (sync_submit) {
+			rc2 = cl_sync_io_wait(env, &ldp_aio->csd_sync,
+					     0);
+			if (result == 0 && rc2)
+				result = rc2;
+			cl_sub_dio_free(ldp_aio, true);
+		}
 		if (unlikely(result < 0))
 			goto out;
 
@@ -399,35 +423,18 @@ static ssize_t ll_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
 	}
 
 out:
-	ll_aio->cda_bytes += tot_bytes;
+	ll_dio_aio->cda_bytes += tot_bytes;
 
 	if (rw == WRITE)
 		vio->u.readwrite.vui_written += tot_bytes;
 	else
 		vio->u.readwrite.vui_read += tot_bytes;
 
-	/* We cannot do async submission - for AIO or regular DIO - unless
-	 * lockless because it causes us to release the lock early.
-	 *
-	 * There are also several circumstances in which we must disable
-	 * parallel DIO, so we check if it is enabled.
-	 *
-	 * The check for "is_sync_kiocb" excludes AIO, which does not need to
-	 * be disabled in these situations.
+	/* AIO is not supported on pipes, so we cannot return EIOCBQEUED like
+	 * we normally would for both DIO and AIO here
 	 */
-	if (io->ci_dio_lock || (is_sync_kiocb(iocb) && !io->ci_parallel_dio)) {
-		ssize_t rc2;
-
-		/* Wait here rather than doing async submission */
-		rc2 = cl_sync_io_wait_recycle(env, &ll_aio->cda_sync, 0, 0);
-		if (result == 0 && rc2)
-			result = rc2;
-
-		if (result == 0)
-			result = tot_bytes;
-	} else if (result == 0) {
+	if (result == 0 && !iov_iter_is_pipe(iter))
 		result = -EIOCBQUEUED;
-	}
 
 	return result;
 }
diff --git a/fs/lustre/obdclass/cl_internal.h b/fs/lustre/obdclass/cl_internal.h
index db9dd98..eb3d81a 100644
--- a/fs/lustre/obdclass/cl_internal.h
+++ b/fs/lustre/obdclass/cl_internal.h
@@ -47,6 +47,7 @@ struct cl_thread_info {
 };
 
 extern struct kmem_cache *cl_dio_aio_kmem;
+extern struct kmem_cache *cl_sub_dio_kmem;
 extern struct kmem_cache *cl_page_kmem_array[16];
 extern unsigned short cl_page_kmem_size_array[16];
 
diff --git a/fs/lustre/obdclass/cl_io.c b/fs/lustre/obdclass/cl_io.c
index c388700..06b9eb8 100644
--- a/fs/lustre/obdclass/cl_io.c
+++ b/fs/lustre/obdclass/cl_io.c
@@ -1072,14 +1072,14 @@ void cl_req_attr_set(const struct lu_env *env, struct cl_object *obj,
  *		anchor->csi_waitq.lock
  */
 void cl_sync_io_init_notify(struct cl_sync_io *anchor, int nr,
-			    struct cl_dio_aio *aio, cl_sync_io_end_t *end)
+			    void *dio_aio, cl_sync_io_end_t *end)
 {
 	memset(anchor, 0, sizeof(*anchor));
 	init_waitqueue_head(&anchor->csi_waitq);
 	atomic_set(&anchor->csi_sync_nr, nr);
 	anchor->csi_sync_rc = 0;
 	anchor->csi_end_io = end;
-	anchor->csi_aio = aio;
+	anchor->csi_dio_aio = dio_aio;
 }
 EXPORT_SYMBOL(cl_sync_io_init_notify);
 
@@ -1117,32 +1117,37 @@ int cl_sync_io_wait(const struct lu_env *env, struct cl_sync_io *anchor,
 }
 EXPORT_SYMBOL(cl_sync_io_wait);
 
-static void cl_aio_end(const struct lu_env *env, struct cl_sync_io *anchor)
+static void cl_dio_aio_end(const struct lu_env *env, struct cl_sync_io *anchor)
 {
 	struct cl_dio_aio *aio = container_of(anchor, typeof(*aio), cda_sync);
 	ssize_t ret = anchor->csi_sync_rc;
 
+	if (!aio->cda_no_aio_complete) {
+		aio->cda_iocb->ki_complete(aio->cda_iocb, ret ?: aio->cda_bytes,
+					   0);
+	}
+}
+
+static void cl_sub_dio_end(const struct lu_env *env, struct cl_sync_io *anchor)
+{
+	struct cl_sub_dio *sdio = container_of(anchor, typeof(*sdio), csd_sync);
+	ssize_t ret = anchor->csi_sync_rc;
+
 	/* release pages */
-	while (aio->cda_pages.pl_nr > 0) {
-		struct cl_page *page = cl_page_list_first(&aio->cda_pages);
+	while (sdio->csd_pages.pl_nr > 0) {
+		struct cl_page *page = cl_page_list_first(&sdio->csd_pages);
 
 		cl_page_delete(env, page);
-		cl_page_list_del(env, &aio->cda_pages, page);
+		cl_page_list_del(env, &sdio->csd_pages, page);
 	}
 
-	if (!aio->cda_no_aio_complete)
-		aio->cda_iocb->ki_complete(aio->cda_iocb,
-					   ret ?: aio->cda_bytes, 0);
-
-	if (aio->cda_ll_aio) {
-		ll_release_user_pages(aio->cda_dio_pages.ldp_pages,
-				      aio->cda_dio_pages.ldp_count);
-		cl_sync_io_note(env, &aio->cda_ll_aio->cda_sync, ret);
-	}
+	ll_release_user_pages(sdio->csd_dio_pages.ldp_pages,
+			      sdio->csd_dio_pages.ldp_count);
+	cl_sync_io_note(env, &sdio->csd_ll_aio->cda_sync, ret);
 }
 
-struct cl_dio_aio *cl_aio_alloc(struct kiocb *iocb, struct cl_object *obj,
-				struct cl_dio_aio *ll_aio)
+struct cl_dio_aio *cl_dio_aio_alloc(struct kiocb *iocb, struct cl_object *obj,
+				    bool is_aio)
 {
 	struct cl_dio_aio *aio;
 
@@ -1152,46 +1157,63 @@ struct cl_dio_aio *cl_aio_alloc(struct kiocb *iocb, struct cl_object *obj,
 		 * Hold one ref so that it won't be released until
 		 * every pages is added.
 		 */
-		cl_sync_io_init_notify(&aio->cda_sync, 1, aio, cl_aio_end);
-		cl_page_list_init(&aio->cda_pages);
+		cl_sync_io_init_notify(&aio->cda_sync, 1, aio, cl_dio_aio_end);
 		aio->cda_iocb = iocb;
-		if (is_sync_kiocb(iocb) || ll_aio)
-			aio->cda_no_aio_complete = 1;
-		else
-			aio->cda_no_aio_complete = 0;
-		/* in the case of a lower level aio struct (ll_aio is set), or
-		 * true AIO (!is_sync_kiocb()), the memory is freed by
-		 * the daemons calling cl_sync_io_note, because they are the
-		 * last users of the aio struct
+		aio->cda_no_aio_complete = !is_aio;
+		/* if this is true AIO, the memory is freed by the last call
+		 * to cl_sync_io_note (when all the I/O is complete), because
+		 * no one is waiting (in the kernel) for this to complete
 		 *
 		 * in other cases, the last user is cl_sync_io_wait, and in
-		 * that case, the caller frees the aio struct after that call
-		 * completes
+		 * that case, the caller frees the struct after that call
 		 */
-		if (ll_aio || !is_sync_kiocb(iocb))
-			aio->cda_no_aio_free = 0;
-		else
-			aio->cda_no_aio_free = 1;
+		aio->cda_no_sub_free = !is_aio;
 
 		cl_object_get(obj);
 		aio->cda_obj = obj;
-		aio->cda_ll_aio = ll_aio;
-
-		if (ll_aio)
-			atomic_add(1,  &ll_aio->cda_sync.csi_sync_nr);
 	}
 	return aio;
 }
-EXPORT_SYMBOL(cl_aio_alloc);
+EXPORT_SYMBOL(cl_dio_aio_alloc);
 
-void cl_aio_free(const struct lu_env *env, struct cl_dio_aio *aio)
+struct cl_sub_dio *cl_sub_dio_alloc(struct cl_dio_aio *ll_aio, bool nofree)
 {
-	if (aio) {
+	struct cl_sub_dio *sdio;
+
+	sdio = kmem_cache_zalloc(cl_sub_dio_kmem, GFP_NOFS);
+	if (sdio) {
+		/*
+		 * Hold one ref so that it won't be released until
+		 * every pages is added.
+		 */
+		cl_sync_io_init_notify(&sdio->csd_sync, 1, sdio,
+				       cl_sub_dio_end);
+		cl_page_list_init(&sdio->csd_pages);
+
+		sdio->csd_ll_aio = ll_aio;
+		atomic_add(1,  &ll_aio->cda_sync.csi_sync_nr);
+		sdio->csd_no_free = nofree;
+	}
+	return sdio;
+}
+EXPORT_SYMBOL(cl_sub_dio_alloc);
+
+void cl_dio_aio_free(const struct lu_env *env, struct cl_dio_aio *aio,
+		     bool always_free)
+{
+	if (aio && (!aio->cda_no_sub_free || always_free)) {
 		cl_object_put(env, aio->cda_obj);
 		kmem_cache_free(cl_dio_aio_kmem, aio);
 	}
 }
-EXPORT_SYMBOL(cl_aio_free);
+EXPORT_SYMBOL(cl_dio_aio_free);
+
+void cl_sub_dio_free(struct cl_sub_dio *sdio, bool always_free)
+{
+	if (sdio && (!sdio->csd_no_free || always_free))
+		kmem_cache_free(cl_sub_dio_kmem, sdio);
+}
+EXPORT_SYMBOL(cl_sub_dio_free);
 
 /*
  * ll_release_user_pages - tear down page struct array
@@ -1225,7 +1247,7 @@ void cl_sync_io_note(const struct lu_env *env, struct cl_sync_io *anchor,
 	LASSERT(atomic_read(&anchor->csi_sync_nr) > 0);
 	if (atomic_dec_and_lock(&anchor->csi_sync_nr,
 				&anchor->csi_waitq.lock)) {
-		struct cl_dio_aio *aio = NULL;
+		void *dio_aio = NULL;
 
 		cl_sync_io_end_t *end_io = anchor->csi_end_io;
 
@@ -1238,29 +1260,28 @@ void cl_sync_io_note(const struct lu_env *env, struct cl_sync_io *anchor,
 		if (end_io)
 			end_io(env, anchor);
 
-		aio = anchor->csi_aio;
+		dio_aio = anchor->csi_dio_aio;
 
 		spin_unlock(&anchor->csi_waitq.lock);
 
-		if (aio && !aio->cda_no_aio_free)
-			cl_aio_free(env, aio);
+		if (dio_aio) {
+			if (end_io == cl_dio_aio_end)
+				cl_dio_aio_free(env,
+						(struct cl_dio_aio *) dio_aio,
+						false);
+			else if (end_io == cl_sub_dio_end)
+				cl_sub_dio_free((struct cl_sub_dio *) dio_aio,
+						false);
+		}
 	}
 }
 EXPORT_SYMBOL(cl_sync_io_note);
 
-
 int cl_sync_io_wait_recycle(const struct lu_env *env, struct cl_sync_io *anchor,
 			    long timeout, int ioret)
 {
-	bool no_aio_free = anchor->csi_aio->cda_no_aio_free;
 	int rc = 0;
 
-	/* for true AIO, the daemons running cl_sync_io_note would normally
-	 * free the aio struct, but if we're waiting on it, we need them to not
-	 * do that.  This ensures the aio is not freed when we drop the
-	 * reference count to zero in cl_sync_io_note below
-	 */
-	anchor->csi_aio->cda_no_aio_free = 1;
 	/*
 	 * @anchor was inited as 1 to prevent end_io to be
 	 * called before we add all pages for IO, so drop
@@ -1280,8 +1301,6 @@ int cl_sync_io_wait_recycle(const struct lu_env *env, struct cl_sync_io *anchor,
 	 */
 	atomic_add(1, &anchor->csi_sync_nr);
 
-	anchor->csi_aio->cda_no_aio_free = no_aio_free;
-
 	return rc;
 }
 EXPORT_SYMBOL(cl_sync_io_wait_recycle);
diff --git a/fs/lustre/obdclass/cl_object.c b/fs/lustre/obdclass/cl_object.c
index 6f87160..28bf1e4 100644
--- a/fs/lustre/obdclass/cl_object.c
+++ b/fs/lustre/obdclass/cl_object.c
@@ -57,6 +57,7 @@
 
 static struct kmem_cache *cl_env_kmem;
 struct kmem_cache *cl_dio_aio_kmem;
+struct kmem_cache *cl_sub_dio_kmem;
 struct kmem_cache *cl_page_kmem_array[16];
 unsigned short cl_page_kmem_size_array[16];
 
@@ -989,6 +990,11 @@ struct cl_thread_info *cl_env_info(const struct lu_env *env)
 		.ckd_size  = sizeof(struct cl_dio_aio)
 	},
 	{
+		.ckd_cache = &cl_sub_dio_kmem,
+		.ckd_name  = "cl_sub_dio_kmem",
+		.ckd_size  = sizeof(struct cl_sub_dio)
+	},
+	{
 		.ckd_cache = NULL
 	}
 };
