1 files changed, 330 insertions, 0 deletions
diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c
new file mode 100644
index 000000000000..b2048287fe90
--- /dev/null
+++ b/net/bluetooth/hci_sync.c
@@ -0,0 +1,330 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * BlueZ - Bluetooth protocol stack for Linux
+ *
+ * Copyright (C) 2021 Intel Corporation
+ */
+
+#include <net/bluetooth/bluetooth.h>
+#include <net/bluetooth/hci_core.h>
+#include <net/bluetooth/mgmt.h>
+
+#include "hci_request.h"
+#include "smp.h"
+
+static void hci_cmd_sync_complete(struct hci_dev *hdev, u8 result, u16 opcode,
+				  struct sk_buff *skb)
+{
+	bt_dev_dbg(hdev, "result 0x%2.2x", result);
+
+	if (hdev->req_status != HCI_REQ_PEND)
+		return;
+
+	hdev->req_result = result;
+	hdev->req_status = HCI_REQ_DONE;
+
+	wake_up_interruptible(&hdev->req_wait_q);
+}
+
+static struct sk_buff *hci_cmd_sync_alloc(struct hci_dev *hdev, u16 opcode,
+					  u32 plen, const void *param,
+					  struct sock *sk)
+{
+	int len = HCI_COMMAND_HDR_SIZE + plen;
+	struct hci_command_hdr *hdr;
+	struct sk_buff *skb;
+
+	skb = bt_skb_alloc(len, GFP_ATOMIC);
+	if (!skb)
+		return NULL;
+
+	hdr = skb_put(skb, HCI_COMMAND_HDR_SIZE);
+	hdr->opcode = cpu_to_le16(opcode);
+	hdr->plen   = plen;
+
+	if (plen)
+		skb_put_data(skb, param, plen);
+
+	bt_dev_dbg(hdev, "skb len %d", skb->len);
+
+	hci_skb_pkt_type(skb) = HCI_COMMAND_PKT;
+	hci_skb_opcode(skb) = opcode;
+
+	return skb;
+}
+
+static void hci_cmd_sync_add(struct hci_request *req, u16 opcode, u32 plen,
+			     const void *param, u8 event, struct sock *sk)
+{
+	struct hci_dev *hdev = req->hdev;
+	struct sk_buff *skb;
+
+	bt_dev_dbg(hdev, "opcode 0x%4.4x plen %d", opcode, plen);
+
+	/* If an error occurred during request building, there is no point in
+	 * queueing the HCI command. We can simply return.
+	 */
+	if (req->err)
+		return;
+
+	skb = hci_cmd_sync_alloc(hdev, opcode, plen, param, sk);
+	if (!skb) {
+		bt_dev_err(hdev, "no memory for command (opcode 0x%4.4x)",
+			   opcode);
+		req->err = -ENOMEM;
+		return;
+	}
+
+	if (skb_queue_empty(&req->cmd_q))
+		bt_cb(skb)->hci.req_flags |= HCI_REQ_START;
+
+	bt_cb(skb)->hci.req_event = event;
+
+	skb_queue_tail(&req->cmd_q, skb);
+}
+
+static int hci_cmd_sync_run(struct hci_request *req)
+{
+	struct hci_dev *hdev = req->hdev;
+	struct sk_buff *skb;
+	unsigned long flags;
+
+	bt_dev_dbg(hdev, "length %u", skb_queue_len(&req->cmd_q));
+
+	/* If an error occurred during request building, remove all HCI
+	 * commands queued on the HCI request queue.
+	 */
+	if (req->err) {
+		skb_queue_purge(&req->cmd_q);
+		return req->err;
+	}
+
+	/* Do not allow empty requests */
+	if (skb_queue_empty(&req->cmd_q))
+		return -ENODATA;
+
+	skb = skb_peek_tail(&req->cmd_q);
+	bt_cb(skb)->hci.req_complete_skb = hci_cmd_sync_complete;
+	bt_cb(skb)->hci.req_flags |= HCI_REQ_SKB;
+
+	spin_lock_irqsave(&hdev->cmd_q.lock, flags);
+	skb_queue_splice_tail(&req->cmd_q, &hdev->cmd_q);
+	spin_unlock_irqrestore(&hdev->cmd_q.lock, flags);
+
+	queue_work(hdev->workqueue, &hdev->cmd_work);
+
+	return 0;
+}
+
+/* This function requires the caller holds hdev->req_lock. */
+struct sk_buff *__hci_cmd_sync_sk(struct hci_dev *hdev, u16 opcode, u32 plen,
+				  const void *param, u8 event, u32 timeout,
+				  struct sock *sk)
+{
+	struct hci_request req;
+	struct sk_buff *skb;
+	int err = 0;
+
+	bt_dev_dbg(hdev, "");
+
+	hci_req_init(&req, hdev);
+
+	hci_cmd_sync_add(&req, opcode, plen, param, event, sk);
+
+	hdev->req_status = HCI_REQ_PEND;
+
+	err = hci_cmd_sync_run(&req);
+	if (err < 0)
+		return ERR_PTR(err);
+
+	err = wait_event_interruptible_timeout(hdev->req_wait_q,
+					       hdev->req_status != HCI_REQ_PEND,
+					       timeout);
+
+	if (err == -ERESTARTSYS)
+		return ERR_PTR(-EINTR);
+
+	switch (hdev->req_status) {
+	case HCI_REQ_DONE:
+		err = -bt_to_errno(hdev->req_result);
+		break;
+
+	case HCI_REQ_CANCELED:
+		err = -hdev->req_result;
+		break;
+
+	default:
+		err = -ETIMEDOUT;
+		break;
+	}
+
+	hdev->req_status = 0;
+	hdev->req_result = 0;
+	skb = hdev->req_skb;
+	hdev->req_skb = NULL;
+
+	bt_dev_dbg(hdev, "end: err %d", err);
+
+	if (err < 0) {
+		kfree_skb(skb);
+		return ERR_PTR(err);
+	}
+
+	if (!skb)
+		return ERR_PTR(-ENODATA);
+
+	return skb;
+}
+EXPORT_SYMBOL(__hci_cmd_sync_sk);
+
+/* This function requires the caller holds hdev->req_lock. */
+struct sk_buff *__hci_cmd_sync(struct hci_dev *hdev, u16 opcode, u32 plen,
+			       const void *param, u32 timeout)
+{
+	return __hci_cmd_sync_sk(hdev, opcode, plen, param, 0, timeout, NULL);
+}
+EXPORT_SYMBOL(__hci_cmd_sync);
+
+/* Send HCI command and wait for command complete event */
+struct sk_buff *hci_cmd_sync(struct hci_dev *hdev, u16 opcode, u32 plen,
+			     const void *param, u32 timeout)
+{
+	struct sk_buff *skb;
+
+	if (!test_bit(HCI_UP, &hdev->flags))
+		return ERR_PTR(-ENETDOWN);
+
+	bt_dev_dbg(hdev, "opcode 0x%4.4x plen %d", opcode, plen);
+
+	hci_req_sync_lock(hdev);
+	skb = __hci_cmd_sync(hdev, opcode, plen, param, timeout);
+	hci_req_sync_unlock(hdev);
+
+	return skb;
+}
+EXPORT_SYMBOL(hci_cmd_sync);
+
+/* This function requires the caller holds hdev->req_lock. */
+struct sk_buff *__hci_cmd_sync_ev(struct hci_dev *hdev, u16 opcode, u32 plen,
+				  const void *param, u8 event, u32 timeout)
+{
+	return __hci_cmd_sync_sk(hdev, opcode, plen, param, event, timeout,
+				 NULL);
+}
+EXPORT_SYMBOL(__hci_cmd_sync_ev);
+
+/* This function requires the caller holds hdev->req_lock. */
+int __hci_cmd_sync_status_sk(struct hci_dev *hdev, u16 opcode, u32 plen,
+			     const void *param, u8 event, u32 timeout,
+			     struct sock *sk)
+{
+	struct sk_buff *skb;
+	u8 status;
+
+	skb = __hci_cmd_sync_sk(hdev, opcode, plen, param, event, timeout, sk);
+	if (IS_ERR_OR_NULL(skb)) {
+		bt_dev_err(hdev, "Opcode 0x%4x failed: %ld", opcode,
+			   PTR_ERR(skb));
+		return PTR_ERR(skb);
+	}
+
+	status = skb->data[0];
+
+	kfree_skb(skb);
+
+	return status;
+}
+EXPORT_SYMBOL(__hci_cmd_sync_status_sk);
+
+int __hci_cmd_sync_status(struct hci_dev *hdev, u16 opcode, u32 plen,
+			  const void *param, u32 timeout)
+{
+	return __hci_cmd_sync_status_sk(hdev, opcode, plen, param, 0, timeout,
+					NULL);
+}
+EXPORT_SYMBOL(__hci_cmd_sync_status);
+
+static void hci_cmd_sync_work(struct work_struct *work)
+{
+	struct hci_dev *hdev = container_of(work, struct hci_dev, cmd_sync_work);
+	struct hci_cmd_sync_work_entry *entry;
+	hci_cmd_sync_work_func_t func;
+	hci_cmd_sync_work_destroy_t destroy;
+	void *data;
+
+	bt_dev_dbg(hdev, "");
+
+	mutex_lock(&hdev->cmd_sync_work_lock);
+	entry = list_first_entry(&hdev->cmd_sync_work_list,
+				 struct hci_cmd_sync_work_entry, list);
+	if (entry) {
+		list_del(&entry->list);
+		func = entry->func;
+		data = entry->data;
+		destroy = entry->destroy;
+		kfree(entry);
+	} else {
+		func = NULL;
+		data = NULL;
+		destroy = NULL;
+	}
+	mutex_unlock(&hdev->cmd_sync_work_lock);
+
+	if (func) {
+		int err;
+
+		hci_req_sync_lock(hdev);
+
+		err = func(hdev, data);
+
+		if (destroy)
+			destroy(hdev, data, err);
+
+		hci_req_sync_unlock(hdev);
+	}
+}
+
+void hci_cmd_sync_init(struct hci_dev *hdev)
+{
+	INIT_WORK(&hdev->cmd_sync_work, hci_cmd_sync_work);
+	INIT_LIST_HEAD(&hdev->cmd_sync_work_list);
+	mutex_init(&hdev->cmd_sync_work_lock);
+}
+
+void hci_cmd_sync_clear(struct hci_dev *hdev)
+{
+	struct hci_cmd_sync_work_entry *entry, *tmp;
+
+	cancel_work_sync(&hdev->cmd_sync_work);
+
+	list_for_each_entry_safe(entry, tmp, &hdev->cmd_sync_work_list, list) {
+		if (entry->destroy)
+			entry->destroy(hdev, entry->data, -ECANCELED);
+
+		list_del(&entry->list);
+		kfree(entry);
+	}
+}
+
+int hci_cmd_sync_queue(struct hci_dev *hdev, hci_cmd_sync_work_func_t func,
+		       void *data, hci_cmd_sync_work_destroy_t destroy)
+{
+	struct hci_cmd_sync_work_entry *entry;
+
+	entry = kmalloc(sizeof(*entry), GFP_KERNEL);
+	if (!entry)
+		return -ENOMEM;
+
+	entry->func = func;
+	entry->data = data;
+	entry->destroy = destroy;
+
+	mutex_lock(&hdev->cmd_sync_work_lock);
+	list_add_tail(&entry->list, &hdev->cmd_sync_work_list);
+	mutex_unlock(&hdev->cmd_sync_work_lock);
+
+	queue_work(hdev->req_workqueue, &hdev->cmd_sync_work);
+
+	return 0;
+}
+EXPORT_SYMBOL(hci_cmd_sync_queue);