diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c
index 317cedfa52bf6..6afa4195113e0 100644
--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -167,83 +167,6 @@ nfs_page_group_lock_head(struct nfs_page *req)
 	return head;
 }
 
-/*
- * nfs_unroll_locks -  unlock all newly locked reqs and wait on @req
- * @head: head request of page group, must be holding head lock
- * @req: request that couldn't lock and needs to wait on the req bit lock
- *
- * This is a helper function for nfs_lock_and_join_requests
- * returns 0 on success, < 0 on error.
- */
-static void
-nfs_unroll_locks(struct nfs_page *head, struct nfs_page *req)
-{
-	struct nfs_page *tmp;
-
-	/* relinquish all the locks successfully grabbed this run */
-	for (tmp = head->wb_this_page ; tmp != req; tmp = tmp->wb_this_page) {
-		if (!kref_read(&tmp->wb_kref))
-			continue;
-		nfs_unlock_and_release_request(tmp);
-	}
-}
-
-/*
- * nfs_page_group_lock_subreq -  try to lock a subrequest
- * @head: head request of page group
- * @subreq: request to lock
- *
- * This is a helper function for nfs_lock_and_join_requests which
- * must be called with the head request and page group both locked.
- * On error, it returns with the page group unlocked.
- */
-static int
-nfs_page_group_lock_subreq(struct nfs_page *head, struct nfs_page *subreq)
-{
-	int ret;
-
-	if (!kref_get_unless_zero(&subreq->wb_kref))
-		return 0;
-	while (!nfs_lock_request(subreq)) {
-		nfs_page_group_unlock(head);
-		ret = nfs_wait_on_request(subreq);
-		if (!ret)
-			ret = nfs_page_group_lock(head);
-		if (ret < 0) {
-			nfs_unroll_locks(head, subreq);
-			nfs_release_request(subreq);
-			return ret;
-		}
-	}
-	return 0;
-}
-
-/*
- * nfs_page_group_lock_subrequests -  try to lock the subrequests
- * @head: head request of page group
- *
- * This is a helper function for nfs_lock_and_join_requests which
- * must be called with the head request locked.
- */
-int nfs_page_group_lock_subrequests(struct nfs_page *head)
-{
-	struct nfs_page *subreq;
-	int ret;
-
-	ret = nfs_page_group_lock(head);
-	if (ret < 0)
-		return ret;
-	/* lock each request in the page group */
-	for (subreq = head->wb_this_page; subreq != head;
-			subreq = subreq->wb_this_page) {
-		ret = nfs_page_group_lock_subreq(head, subreq);
-		if (ret < 0)
-			return ret;
-	}
-	nfs_page_group_unlock(head);
-	return 0;
-}
-
 /*
  * nfs_page_set_headlock - set the request PG_HEADLOCK
  * @req: request that is to be locked
@@ -310,13 +233,14 @@ nfs_page_group_unlock(struct nfs_page *req)
 	nfs_page_clear_headlock(req);
 }
 
-/*
- * nfs_page_group_sync_on_bit_locked
+/**
+ * nfs_page_group_sync_on_bit_locked - Test if all requests have @bit set
+ * @req: request in page group
+ * @bit: PG_* bit that is used to sync page group
  *
  * must be called with page group lock held
  */
-static bool
-nfs_page_group_sync_on_bit_locked(struct nfs_page *req, unsigned int bit)
+bool nfs_page_group_sync_on_bit_locked(struct nfs_page *req, unsigned int bit)
 {
 	struct nfs_page *head = req->wb_head;
 	struct nfs_page *tmp;
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index eb39ba74a570b..2df426dac8ae7 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -154,20 +154,10 @@ nfs_page_set_inode_ref(struct nfs_page *req, struct inode *inode)
 	}
 }
 
-static int
-nfs_cancel_remove_inode(struct nfs_page *req, struct inode *inode)
+static void nfs_cancel_remove_inode(struct nfs_page *req, struct inode *inode)
 {
-	int ret;
-
-	if (!test_bit(PG_REMOVE, &req->wb_flags))
-		return 0;
-	ret = nfs_page_group_lock(req);
-	if (ret)
-		return ret;
 	if (test_and_clear_bit(PG_REMOVE, &req->wb_flags))
 		nfs_page_set_inode_ref(req, inode);
-	nfs_page_group_unlock(req);
-	return 0;
 }
 
 static struct nfs_page *
@@ -239,36 +229,6 @@ static struct nfs_page *nfs_page_find_head_request(struct page *page)
 	return req;
 }
 
-static struct nfs_page *nfs_find_and_lock_page_request(struct page *page)
-{
-	struct inode *inode = page_file_mapping(page)->host;
-	struct nfs_page *req, *head;
-	int ret;
-
-	for (;;) {
-		req = nfs_page_find_head_request(page);
-		if (!req)
-			return req;
-		head = nfs_page_group_lock_head(req);
-		if (head != req)
-			nfs_release_request(req);
-		if (IS_ERR(head))
-			return head;
-		ret = nfs_cancel_remove_inode(head, inode);
-		if (ret < 0) {
-			nfs_unlock_and_release_request(head);
-			return ERR_PTR(ret);
-		}
-		/* Ensure that nobody removed the request before we locked it */
-		if (head == nfs_page_private_request(page))
-			break;
-		if (PageSwapCache(page))
-			break;
-		nfs_unlock_and_release_request(head);
-	}
-	return head;
-}
-
 /* Adjust the file length if we're writing beyond the end */
 static void nfs_grow_file(struct page *page, unsigned int offset, unsigned int count)
 {
@@ -547,6 +507,57 @@ nfs_join_page_group(struct nfs_page *head, struct inode *inode)
 	nfs_destroy_unlinked_subrequests(destroy_list, head, inode);
 }
 
+/*
+ * nfs_unroll_locks -  unlock all newly locked reqs and wait on @req
+ * @head: head request of page group, must be holding head lock
+ * @req: request that couldn't lock and needs to wait on the req bit lock
+ *
+ * This is a helper function for nfs_lock_and_join_requests
+ * returns 0 on success, < 0 on error.
+ */
+static void
+nfs_unroll_locks(struct nfs_page *head, struct nfs_page *req)
+{
+	struct nfs_page *tmp;
+
+	/* relinquish all the locks successfully grabbed this run */
+	for (tmp = head->wb_this_page ; tmp != req; tmp = tmp->wb_this_page) {
+		if (!kref_read(&tmp->wb_kref))
+			continue;
+		nfs_unlock_and_release_request(tmp);
+	}
+}
+
+/*
+ * nfs_page_group_lock_subreq -  try to lock a subrequest
+ * @head: head request of page group
+ * @subreq: request to lock
+ *
+ * This is a helper function for nfs_lock_and_join_requests which
+ * must be called with the head request and page group both locked.
+ * On error, it returns with the page group unlocked.
+ */
+static int
+nfs_page_group_lock_subreq(struct nfs_page *head, struct nfs_page *subreq)
+{
+	int ret;
+
+	if (!kref_get_unless_zero(&subreq->wb_kref))
+		return 0;
+	while (!nfs_lock_request(subreq)) {
+		nfs_page_group_unlock(head);
+		ret = nfs_wait_on_request(subreq);
+		if (!ret)
+			ret = nfs_page_group_lock(head);
+		if (ret < 0) {
+			nfs_unroll_locks(head, subreq);
+			nfs_release_request(subreq);
+			return ret;
+		}
+	}
+	return 0;
+}
+
 /*
  * nfs_lock_and_join_requests - join all subreqs to the head req
  * @page: the page used to lookup the "page group" of nfs_page structures
@@ -566,7 +577,7 @@ static struct nfs_page *
 nfs_lock_and_join_requests(struct page *page)
 {
 	struct inode *inode = page_file_mapping(page)->host;
-	struct nfs_page *head;
+	struct nfs_page *head, *subreq;
 	int ret;
 
 	/*
@@ -574,20 +585,49 @@ nfs_lock_and_join_requests(struct page *page)
 	 * reference to the whole page group - the group will not be destroyed
 	 * until the head reference is released.
 	 */
-	head = nfs_find_and_lock_page_request(page);
+retry:
+	head = nfs_page_find_head_request(page);
 	if (IS_ERR_OR_NULL(head))
 		return head;
 
-	/* lock each request in the page group */
-	ret = nfs_page_group_lock_subrequests(head);
-	if (ret < 0) {
+	while (!nfs_lock_request(head)) {
+		ret = nfs_wait_on_request(head);
+		if (ret < 0) {
+			nfs_release_request(head);
+			return ERR_PTR(ret);
+		}
+	}
+
+	ret = nfs_page_group_lock(head);
+	if (ret < 0)
+		goto out_unlock;
+
+	/* Ensure that nobody removed the request before we locked it */
+	if (head != nfs_page_private_request(page) && !PageSwapCache(page)) {
+		nfs_page_group_unlock(head);
 		nfs_unlock_and_release_request(head);
-		return ERR_PTR(ret);
+		goto retry;
 	}
 
-	nfs_join_page_group(head, inode);
+	nfs_cancel_remove_inode(head, inode);
 
+	/* lock each request in the page group */
+	for (subreq = head->wb_this_page;
+	     subreq != head;
+	     subreq = subreq->wb_this_page) {
+		ret = nfs_page_group_lock_subreq(head, subreq);
+		if (ret < 0)
+			goto out_unlock;
+	}
+
+	nfs_page_group_unlock(head);
+
+	nfs_join_page_group(head, inode);
 	return head;
+
+out_unlock:
+	nfs_unlock_and_release_request(head);
+	return ERR_PTR(ret);
 }
 
 static void nfs_write_error(struct nfs_page *req, int error)
@@ -788,7 +828,8 @@ static void nfs_inode_remove_request(struct nfs_page *req)
 	struct nfs_inode *nfsi = NFS_I(inode);
 	struct nfs_page *head;
 
-	if (nfs_page_group_sync_on_bit(req, PG_REMOVE)) {
+	nfs_page_group_lock(req);
+	if (nfs_page_group_sync_on_bit_locked(req, PG_REMOVE)) {
 		head = req->wb_head;
 
 		spin_lock(&mapping->private_lock);
@@ -799,6 +840,7 @@ static void nfs_inode_remove_request(struct nfs_page *req)
 		}
 		spin_unlock(&mapping->private_lock);
 	}
+	nfs_page_group_unlock(req);
 
 	if (test_and_clear_bit(PG_INODE_REF, &req->wb_flags)) {
 		nfs_release_request(req);
diff --git a/include/linux/nfs_page.h b/include/linux/nfs_page.h
index f0373a6cb5fb6..d6e6a9376ee45 100644
--- a/include/linux/nfs_page.h
+++ b/include/linux/nfs_page.h
@@ -144,11 +144,11 @@ extern  int nfs_wait_on_request(struct nfs_page *);
 extern	void nfs_unlock_request(struct nfs_page *req);
 extern	void nfs_unlock_and_release_request(struct nfs_page *);
 extern	struct nfs_page *nfs_page_group_lock_head(struct nfs_page *req);
-extern	int nfs_page_group_lock_subrequests(struct nfs_page *head);
 extern	void nfs_join_page_group(struct nfs_page *head, struct inode *inode);
 extern int nfs_page_group_lock(struct nfs_page *);
 extern void nfs_page_group_unlock(struct nfs_page *);
 extern bool nfs_page_group_sync_on_bit(struct nfs_page *, unsigned int);
+extern bool nfs_page_group_sync_on_bit_locked(struct nfs_page *, unsigned int);
 extern	int nfs_page_set_headlock(struct nfs_page *req);
 extern void nfs_page_clear_headlock(struct nfs_page *req);
 extern bool nfs_async_iocounter_wait(struct rpc_task *, struct nfs_lock_context *);
diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index e7862903187d8..5833eccdb881a 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -28,6 +28,7 @@
 #include <linux/idr.h>
 #include <linux/leds.h>
 #include <linux/rculist.h>
+#include <linux/srcu.h>
 
 #include <net/bluetooth/hci.h>
 #include <net/bluetooth/hci_sync.h>
@@ -345,6 +346,7 @@ struct amp_assoc {
 
 struct hci_dev {
 	struct list_head list;
+	struct srcu_struct srcu;
 	struct mutex	lock;
 
 	char		name[8];
diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index fd3145e81e87f..52ccb0e8d9f2c 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -109,7 +109,7 @@ static int hci_linkpol_req(struct hci_request *req, unsigned long opt)
 
 /* Get HCI device by index.
  * Device is held on return. */
-struct hci_dev *hci_dev_get(int index)
+static struct hci_dev *__hci_dev_get(int index, int *srcu_index)
 {
 	struct hci_dev *hdev = NULL, *d;
 
@@ -122,6 +122,8 @@ struct hci_dev *hci_dev_get(int index)
 	list_for_each_entry(d, &hci_dev_list, list) {
 		if (d->id == index) {
 			hdev = hci_dev_hold(d);
+			if (srcu_index)
+				*srcu_index = srcu_read_lock(&d->srcu);
 			break;
 		}
 	}
@@ -129,6 +131,22 @@ struct hci_dev *hci_dev_get(int index)
 	return hdev;
 }
 
+struct hci_dev *hci_dev_get(int index)
+{
+	return __hci_dev_get(index, NULL);
+}
+
+static struct hci_dev *hci_dev_get_srcu(int index, int *srcu_index)
+{
+	return __hci_dev_get(index, srcu_index);
+}
+
+static void hci_dev_put_srcu(struct hci_dev *hdev, int srcu_index)
+{
+	srcu_read_unlock(&hdev->srcu, srcu_index);
+	hci_dev_put(hdev);
+}
+
 /* ---- Inquiry support ---- */
 
 bool hci_discovery_active(struct hci_dev *hdev)
@@ -639,9 +657,9 @@ static int hci_dev_do_reset(struct hci_dev *hdev)
 int hci_dev_reset(__u16 dev)
 {
 	struct hci_dev *hdev;
-	int err;
+	int err, srcu_index;
 
-	hdev = hci_dev_get(dev);
+	hdev = hci_dev_get_srcu(dev, &srcu_index);
 	if (!hdev)
 		return -ENODEV;
 
@@ -663,7 +681,7 @@ int hci_dev_reset(__u16 dev)
 	err = hci_dev_do_reset(hdev);
 
 done:
-	hci_dev_put(hdev);
+	hci_dev_put_srcu(hdev, srcu_index);
 	return err;
 }
 
@@ -2432,6 +2450,11 @@ struct hci_dev *hci_alloc_dev_priv(int sizeof_priv)
 	if (!hdev)
 		return NULL;
 
+	if (init_srcu_struct(&hdev->srcu)) {
+		kfree(hdev);
+		return NULL;
+	}
+
 	hdev->pkt_type  = (HCI_DM1 | HCI_DH1 | HCI_HV1);
 	hdev->esco_type = (ESCO_HV1);
 	hdev->link_mode = (HCI_LM_ACCEPT);
@@ -2684,6 +2707,9 @@ void hci_unregister_dev(struct hci_dev *hdev)
 	list_del(&hdev->list);
 	write_unlock(&hci_dev_list_lock);
 
+	synchronize_srcu(&hdev->srcu);
+	cleanup_srcu_struct(&hdev->srcu);
+
 	cancel_work_sync(&hdev->power_on);
 
 	hci_cmd_sync_clear(hdev);