Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1324 insertions, 0 deletions

diff --git a/net/qrtr/af_qrtr.c b/net/qrtr/af_qrtr.c
new file mode 100644
index 000000000..76f0434d3
--- /dev/null
+++ b/net/qrtr/af_qrtr.c
@@ -0,0 +1,1324 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2015, Sony Mobile Communications Inc.
+ * Copyright (c) 2013, The Linux Foundation. All rights reserved.
+ */
+#include <linux/module.h>
+#include <linux/netlink.h>
+#include <linux/qrtr.h>
+#include <linux/termios.h>	/* For TIOCINQ/OUTQ */
+#include <linux/spinlock.h>
+#include <linux/wait.h>
+
+#include <net/sock.h>
+
+#include "qrtr.h"
+
+#define QRTR_PROTO_VER_1 1
+#define QRTR_PROTO_VER_2 3
+
+/* auto-bind range */
+#define QRTR_MIN_EPH_SOCKET 0x4000
+#define QRTR_MAX_EPH_SOCKET 0x7fff
+#define QRTR_EPH_PORT_RANGE \
+		XA_LIMIT(QRTR_MIN_EPH_SOCKET, QRTR_MAX_EPH_SOCKET)
+
+/**
+ * struct qrtr_hdr_v1 - (I|R)PCrouter packet header version 1
+ * @version: protocol version
+ * @type: packet type; one of QRTR_TYPE_*
+ * @src_node_id: source node
+ * @src_port_id: source port
+ * @confirm_rx: boolean; whether a resume-tx packet should be send in reply
+ * @size: length of packet, excluding this header
+ * @dst_node_id: destination node
+ * @dst_port_id: destination port
+ */
+struct qrtr_hdr_v1 {
+	__le32 version;
+	__le32 type;
+	__le32 src_node_id;
+	__le32 src_port_id;
+	__le32 confirm_rx;
+	__le32 size;
+	__le32 dst_node_id;
+	__le32 dst_port_id;
+} __packed;
+
+/**
+ * struct qrtr_hdr_v2 - (I|R)PCrouter packet header later versions
+ * @version: protocol version
+ * @type: packet type; one of QRTR_TYPE_*
+ * @flags: bitmask of QRTR_FLAGS_*
+ * @optlen: length of optional header data
+ * @size: length of packet, excluding this header and optlen
+ * @src_node_id: source node
+ * @src_port_id: source port
+ * @dst_node_id: destination node
+ * @dst_port_id: destination port
+ */
+struct qrtr_hdr_v2 {
+	u8 version;
+	u8 type;
+	u8 flags;
+	u8 optlen;
+	__le32 size;
+	__le16 src_node_id;
+	__le16 src_port_id;
+	__le16 dst_node_id;
+	__le16 dst_port_id;
+};
+
+#define QRTR_FLAGS_CONFIRM_RX	BIT(0)
+
+struct qrtr_cb {
+	u32 src_node;
+	u32 src_port;
+	u32 dst_node;
+	u32 dst_port;
+
+	u8 type;
+	u8 confirm_rx;
+};
+
+#define QRTR_HDR_MAX_SIZE max_t(size_t, sizeof(struct qrtr_hdr_v1), \
+					sizeof(struct qrtr_hdr_v2))
+
+struct qrtr_sock {
+	/* WARNING: sk must be the first member */
+	struct sock sk;
+	struct sockaddr_qrtr us;
+	struct sockaddr_qrtr peer;
+};
+
+static inline struct qrtr_sock *qrtr_sk(struct sock *sk)
+{
+	BUILD_BUG_ON(offsetof(struct qrtr_sock, sk) != 0);
+	return container_of(sk, struct qrtr_sock, sk);
+}
+
+static unsigned int qrtr_local_nid = 1;
+
+/* for node ids */
+static RADIX_TREE(qrtr_nodes, GFP_ATOMIC);
+static DEFINE_SPINLOCK(qrtr_nodes_lock);
+/* broadcast list */
+static LIST_HEAD(qrtr_all_nodes);
+/* lock for qrtr_all_nodes and node reference */
+static DEFINE_MUTEX(qrtr_node_lock);
+
+/* local port allocation management */
+static DEFINE_XARRAY_ALLOC(qrtr_ports);
+
+/**
+ * struct qrtr_node - endpoint node
+ * @ep_lock: lock for endpoint management and callbacks
+ * @ep: endpoint
+ * @ref: reference count for node
+ * @nid: node id
+ * @qrtr_tx_flow: tree of qrtr_tx_flow, keyed by node << 32 | port
+ * @qrtr_tx_lock: lock for qrtr_tx_flow inserts
+ * @rx_queue: receive queue
+ * @item: list item for broadcast list
+ */
+struct qrtr_node {
+	struct mutex ep_lock;
+	struct qrtr_endpoint *ep;
+	struct kref ref;
+	unsigned int nid;
+
+	struct radix_tree_root qrtr_tx_flow;
+	struct mutex qrtr_tx_lock; /* for qrtr_tx_flow */
+
+	struct sk_buff_head rx_queue;
+	struct list_head item;
+};
+
+/**
+ * struct qrtr_tx_flow - tx flow control
+ * @resume_tx: waiters for a resume tx from the remote
+ * @pending: number of waiting senders
+ * @tx_failed: indicates that a message with confirm_rx flag was lost
+ */
+struct qrtr_tx_flow {
+	struct wait_queue_head resume_tx;
+	int pending;
+	int tx_failed;
+};
+
+#define QRTR_TX_FLOW_HIGH	10
+#define QRTR_TX_FLOW_LOW	5
+
+static int qrtr_local_enqueue(struct qrtr_node *node, struct sk_buff *skb,
+			      int type, struct sockaddr_qrtr *from,
+			      struct sockaddr_qrtr *to);
+static int qrtr_bcast_enqueue(struct qrtr_node *node, struct sk_buff *skb,
+			      int type, struct sockaddr_qrtr *from,
+			      struct sockaddr_qrtr *to);
+static struct qrtr_sock *qrtr_port_lookup(int port);
+static void qrtr_port_put(struct qrtr_sock *ipc);
+
+/* Release node resources and free the node.
+ *
+ * Do not call directly, use qrtr_node_release.  To be used with
+ * kref_put_mutex.  As such, the node mutex is expected to be locked on call.
+ */
+static void __qrtr_node_release(struct kref *kref)
+{
+	struct qrtr_node *node = container_of(kref, struct qrtr_node, ref);
+	struct radix_tree_iter iter;
+	struct qrtr_tx_flow *flow;
+	unsigned long flags;
+	void __rcu **slot;
+
+	spin_lock_irqsave(&qrtr_nodes_lock, flags);
+	/* If the node is a bridge for other nodes, there are possibly
+	 * multiple entries pointing to our released node, delete them all.
+	 */
+	radix_tree_for_each_slot(slot, &qrtr_nodes, &iter, 0) {
+		if (*slot == node)
+			radix_tree_iter_delete(&qrtr_nodes, &iter, slot);
+	}
+	spin_unlock_irqrestore(&qrtr_nodes_lock, flags);
+
+	list_del(&node->item);
+	mutex_unlock(&qrtr_node_lock);
+
+	skb_queue_purge(&node->rx_queue);
+
+	/* Free tx flow counters */
+	radix_tree_for_each_slot(slot, &node->qrtr_tx_flow, &iter, 0) {
+		flow = *slot;
+		radix_tree_iter_delete(&node->qrtr_tx_flow, &iter, slot);
+		kfree(flow);
+	}
+	kfree(node);
+}
+
+/* Increment reference to node. */
+static struct qrtr_node *qrtr_node_acquire(struct qrtr_node *node)
+{
+	if (node)
+		kref_get(&node->ref);
+	return node;
+}
+
+/* Decrement reference to node and release as necessary. */
+static void qrtr_node_release(struct qrtr_node *node)
+{
+	if (!node)
+		return;
+	kref_put_mutex(&node->ref, __qrtr_node_release, &qrtr_node_lock);
+}
+
+/**
+ * qrtr_tx_resume() - reset flow control counter
+ * @node:	qrtr_node that the QRTR_TYPE_RESUME_TX packet arrived on
+ * @skb:	resume_tx packet
+ */
+static void qrtr_tx_resume(struct qrtr_node *node, struct sk_buff *skb)
+{
+	struct qrtr_ctrl_pkt *pkt = (struct qrtr_ctrl_pkt *)skb->data;
+	u64 remote_node = le32_to_cpu(pkt->client.node);
+	u32 remote_port = le32_to_cpu(pkt->client.port);
+	struct qrtr_tx_flow *flow;
+	unsigned long key;
+
+	key = remote_node << 32 | remote_port;
+
+	rcu_read_lock();
+	flow = radix_tree_lookup(&node->qrtr_tx_flow, key);
+	rcu_read_unlock();
+	if (flow) {
+		spin_lock(&flow->resume_tx.lock);
+		flow->pending = 0;
+		spin_unlock(&flow->resume_tx.lock);
+		wake_up_interruptible_all(&flow->resume_tx);
+	}
+
+	consume_skb(skb);
+}
+
+/**
+ * qrtr_tx_wait() - flow control for outgoing packets
+ * @node:	qrtr_node that the packet is to be send to
+ * @dest_node:	node id of the destination
+ * @dest_port:	port number of the destination
+ * @type:	type of message
+ *
+ * The flow control scheme is based around the low and high "watermarks". When
+ * the low watermark is passed the confirm_rx flag is set on the outgoing
+ * message, which will trigger the remote to send a control message of the type
+ * QRTR_TYPE_RESUME_TX to reset the counter. If the high watermark is hit
+ * further transmision should be paused.
+ *
+ * Return: 1 if confirm_rx should be set, 0 otherwise or errno failure
+ */
+static int qrtr_tx_wait(struct qrtr_node *node, int dest_node, int dest_port,
+			int type)
+{
+	unsigned long key = (u64)dest_node << 32 | dest_port;
+	struct qrtr_tx_flow *flow;
+	int confirm_rx = 0;
+	int ret;
+
+	/* Never set confirm_rx on non-data packets */
+	if (type != QRTR_TYPE_DATA)
+		return 0;
+
+	mutex_lock(&node->qrtr_tx_lock);
+	flow = radix_tree_lookup(&node->qrtr_tx_flow, key);
+	if (!flow) {
+		flow = kzalloc(sizeof(*flow), GFP_KERNEL);
+		if (flow) {
+			init_waitqueue_head(&flow->resume_tx);
+			if (radix_tree_insert(&node->qrtr_tx_flow, key, flow)) {
+				kfree(flow);
+				flow = NULL;
+			}
+		}
+	}
+	mutex_unlock(&node->qrtr_tx_lock);
+
+	/* Set confirm_rx if we where unable to find and allocate a flow */
+	if (!flow)
+		return 1;
+
+	spin_lock_irq(&flow->resume_tx.lock);
+	ret = wait_event_interruptible_locked_irq(flow->resume_tx,
+						  flow->pending < QRTR_TX_FLOW_HIGH ||
+						  flow->tx_failed ||
+						  !node->ep);
+	if (ret < 0) {
+		confirm_rx = ret;
+	} else if (!node->ep) {
+		confirm_rx = -EPIPE;
+	} else if (flow->tx_failed) {
+		flow->tx_failed = 0;
+		confirm_rx = 1;
+	} else {
+		flow->pending++;
+		confirm_rx = flow->pending == QRTR_TX_FLOW_LOW;
+	}
+	spin_unlock_irq(&flow->resume_tx.lock);
+
+	return confirm_rx;
+}
+
+/**
+ * qrtr_tx_flow_failed() - flag that tx of confirm_rx flagged messages failed
+ * @node:	qrtr_node that the packet is to be send to
+ * @dest_node:	node id of the destination
+ * @dest_port:	port number of the destination
+ *
+ * Signal that the transmission of a message with confirm_rx flag failed. The
+ * flow's "pending" counter will keep incrementing towards QRTR_TX_FLOW_HIGH,
+ * at which point transmission would stall forever waiting for the resume TX
+ * message associated with the dropped confirm_rx message.
+ * Work around this by marking the flow as having a failed transmission and
+ * cause the next transmission attempt to be sent with the confirm_rx.
+ */
+static void qrtr_tx_flow_failed(struct qrtr_node *node, int dest_node,
+				int dest_port)
+{
+	unsigned long key = (u64)dest_node << 32 | dest_port;
+	struct qrtr_tx_flow *flow;
+
+	rcu_read_lock();
+	flow = radix_tree_lookup(&node->qrtr_tx_flow, key);
+	rcu_read_unlock();
+	if (flow) {
+		spin_lock_irq(&flow->resume_tx.lock);
+		flow->tx_failed = 1;
+		spin_unlock_irq(&flow->resume_tx.lock);
+	}
+}
+
+/* Pass an outgoing packet socket buffer to the endpoint driver. */
+static int qrtr_node_enqueue(struct qrtr_node *node, struct sk_buff *skb,
+			     int type, struct sockaddr_qrtr *from,
+			     struct sockaddr_qrtr *to)
+{
+	struct qrtr_hdr_v1 *hdr;
+	size_t len = skb->len;
+	int rc, confirm_rx;
+
+	confirm_rx = qrtr_tx_wait(node, to->sq_node, to->sq_port, type);
+	if (confirm_rx < 0) {
+		kfree_skb(skb);
+		return confirm_rx;
+	}
+
+	hdr = skb_push(skb, sizeof(*hdr));
+	hdr->version = cpu_to_le32(QRTR_PROTO_VER_1);
+	hdr->type = cpu_to_le32(type);
+	hdr->src_node_id = cpu_to_le32(from->sq_node);
+	hdr->src_port_id = cpu_to_le32(from->sq_port);
+	if (to->sq_port == QRTR_PORT_CTRL) {
+		hdr->dst_node_id = cpu_to_le32(node->nid);
+		hdr->dst_port_id = cpu_to_le32(QRTR_PORT_CTRL);
+	} else {
+		hdr->dst_node_id = cpu_to_le32(to->sq_node);
+		hdr->dst_port_id = cpu_to_le32(to->sq_port);
+	}
+
+	hdr->size = cpu_to_le32(len);
+	hdr->confirm_rx = !!confirm_rx;
+
+	rc = skb_put_padto(skb, ALIGN(len, 4) + sizeof(*hdr));
+
+	if (!rc) {
+		mutex_lock(&node->ep_lock);
+		rc = -ENODEV;
+		if (node->ep)
+			rc = node->ep->xmit(node->ep, skb);
+		else
+			kfree_skb(skb);
+		mutex_unlock(&node->ep_lock);
+	}
+	/* Need to ensure that a subsequent message carries the otherwise lost
+	 * confirm_rx flag if we dropped this one */
+	if (rc && confirm_rx)
+		qrtr_tx_flow_failed(node, to->sq_node, to->sq_port);
+
+	return rc;
+}
+
+/* Lookup node by id.
+ *
+ * callers must release with qrtr_node_release()
+ */
+static struct qrtr_node *qrtr_node_lookup(unsigned int nid)
+{
+	struct qrtr_node *node;
+	unsigned long flags;
+
+	mutex_lock(&qrtr_node_lock);
+	spin_lock_irqsave(&qrtr_nodes_lock, flags);
+	node = radix_tree_lookup(&qrtr_nodes, nid);
+	node = qrtr_node_acquire(node);
+	spin_unlock_irqrestore(&qrtr_nodes_lock, flags);
+	mutex_unlock(&qrtr_node_lock);
+
+	return node;
+}
+
+/* Assign node id to node.
+ *
+ * This is mostly useful for automatic node id assignment, based on
+ * the source id in the incoming packet.
+ */
+static void qrtr_node_assign(struct qrtr_node *node, unsigned int nid)
+{
+	unsigned long flags;
+
+	if (nid == QRTR_EP_NID_AUTO)
+		return;
+
+	spin_lock_irqsave(&qrtr_nodes_lock, flags);
+	radix_tree_insert(&qrtr_nodes, nid, node);
+	if (node->nid == QRTR_EP_NID_AUTO)
+		node->nid = nid;
+	spin_unlock_irqrestore(&qrtr_nodes_lock, flags);
+}
+
+/**
+ * qrtr_endpoint_post() - post incoming data
+ * @ep: endpoint handle
+ * @data: data pointer
+ * @len: size of data in bytes
+ *
+ * Return: 0 on success; negative error code on failure
+ */
+int qrtr_endpoint_post(struct qrtr_endpoint *ep, const void *data, size_t len)
+{
+	struct qrtr_node *node = ep->node;
+	const struct qrtr_hdr_v1 *v1;
+	const struct qrtr_hdr_v2 *v2;
+	struct qrtr_sock *ipc;
+	struct sk_buff *skb;
+	struct qrtr_cb *cb;
+	size_t size;
+	unsigned int ver;
+	size_t hdrlen;
+
+	if (len == 0 || len & 3)
+		return -EINVAL;
+
+	skb = __netdev_alloc_skb(NULL, len, GFP_ATOMIC | __GFP_NOWARN);
+	if (!skb)
+		return -ENOMEM;
+
+	cb = (struct qrtr_cb *)skb->cb;
+
+	/* Version field in v1 is little endian, so this works for both cases */
+	ver = *(u8*)data;
+
+	switch (ver) {
+	case QRTR_PROTO_VER_1:
+		if (len < sizeof(*v1))
+			goto err;
+		v1 = data;
+		hdrlen = sizeof(*v1);
+
+		cb->type = le32_to_cpu(v1->type);
+		cb->src_node = le32_to_cpu(v1->src_node_id);
+		cb->src_port = le32_to_cpu(v1->src_port_id);
+		cb->confirm_rx = !!v1->confirm_rx;
+		cb->dst_node = le32_to_cpu(v1->dst_node_id);
+		cb->dst_port = le32_to_cpu(v1->dst_port_id);
+
+		size = le32_to_cpu(v1->size);
+		break;
+	case QRTR_PROTO_VER_2:
+		if (len < sizeof(*v2))
+			goto err;
+		v2 = data;
+		hdrlen = sizeof(*v2) + v2->optlen;
+
+		cb->type = v2->type;
+		cb->confirm_rx = !!(v2->flags & QRTR_FLAGS_CONFIRM_RX);
+		cb->src_node = le16_to_cpu(v2->src_node_id);
+		cb->src_port = le16_to_cpu(v2->src_port_id);
+		cb->dst_node = le16_to_cpu(v2->dst_node_id);
+		cb->dst_port = le16_to_cpu(v2->dst_port_id);
+
+		if (cb->src_port == (u16)QRTR_PORT_CTRL)
+			cb->src_port = QRTR_PORT_CTRL;
+		if (cb->dst_port == (u16)QRTR_PORT_CTRL)
+			cb->dst_port = QRTR_PORT_CTRL;
+
+		size = le32_to_cpu(v2->size);
+		break;
+	default:
+		pr_err("qrtr: Invalid version %d\n", ver);
+		goto err;
+	}
+
+	if (!size || len != ALIGN(size, 4) + hdrlen)
+		goto err;
+
+	if ((cb->type == QRTR_TYPE_NEW_SERVER ||
+	     cb->type == QRTR_TYPE_RESUME_TX) &&
+	    size < sizeof(struct qrtr_ctrl_pkt))
+		goto err;
+
+	if (cb->dst_port != QRTR_PORT_CTRL && cb->type != QRTR_TYPE_DATA &&
+	    cb->type != QRTR_TYPE_RESUME_TX)
+		goto err;
+
+	skb_put_data(skb, data + hdrlen, size);
+
+	qrtr_node_assign(node, cb->src_node);
+
+	if (cb->type == QRTR_TYPE_NEW_SERVER) {
+		/* Remote node endpoint can bridge other distant nodes */
+		const struct qrtr_ctrl_pkt *pkt;
+
+		pkt = data + hdrlen;
+		qrtr_node_assign(node, le32_to_cpu(pkt->server.node));
+	}
+
+	if (cb->type == QRTR_TYPE_RESUME_TX) {
+		qrtr_tx_resume(node, skb);
+	} else {
+		ipc = qrtr_port_lookup(cb->dst_port);
+		if (!ipc)
+			goto err;
+
+		if (sock_queue_rcv_skb(&ipc->sk, skb)) {
+			qrtr_port_put(ipc);
+			goto err;
+		}
+
+		qrtr_port_put(ipc);
+	}
+
+	return 0;
+
+err:
+	kfree_skb(skb);
+	return -EINVAL;
+
+}
+EXPORT_SYMBOL_GPL(qrtr_endpoint_post);
+
+/**
+ * qrtr_alloc_ctrl_packet() - allocate control packet skb
+ * @pkt: reference to qrtr_ctrl_pkt pointer
+ * @flags: the type of memory to allocate
+ *
+ * Returns newly allocated sk_buff, or NULL on failure
+ *
+ * This function allocates a sk_buff large enough to carry a qrtr_ctrl_pkt and
+ * on success returns a reference to the control packet in @pkt.
+ */
+static struct sk_buff *qrtr_alloc_ctrl_packet(struct qrtr_ctrl_pkt **pkt,
+					      gfp_t flags)
+{
+	const int pkt_len = sizeof(struct qrtr_ctrl_pkt);
+	struct sk_buff *skb;
+
+	skb = alloc_skb(QRTR_HDR_MAX_SIZE + pkt_len, flags);
+	if (!skb)
+		return NULL;
+
+	skb_reserve(skb, QRTR_HDR_MAX_SIZE);
+	*pkt = skb_put_zero(skb, pkt_len);
+
+	return skb;
+}
+
+/**
+ * qrtr_endpoint_register() - register a new endpoint
+ * @ep: endpoint to register
+ * @nid: desired node id; may be QRTR_EP_NID_AUTO for auto-assignment
+ * Return: 0 on success; negative error code on failure
+ *
+ * The specified endpoint must have the xmit function pointer set on call.
+ */
+int qrtr_endpoint_register(struct qrtr_endpoint *ep, unsigned int nid)
+{
+	struct qrtr_node *node;
+
+	if (!ep || !ep->xmit)
+		return -EINVAL;
+
+	node = kzalloc(sizeof(*node), GFP_KERNEL);
+	if (!node)
+		return -ENOMEM;
+
+	kref_init(&node->ref);
+	mutex_init(&node->ep_lock);
+	skb_queue_head_init(&node->rx_queue);
+	node->nid = QRTR_EP_NID_AUTO;
+	node->ep = ep;
+
+	INIT_RADIX_TREE(&node->qrtr_tx_flow, GFP_KERNEL);
+	mutex_init(&node->qrtr_tx_lock);
+
+	qrtr_node_assign(node, nid);
+
+	mutex_lock(&qrtr_node_lock);
+	list_add(&node->item, &qrtr_all_nodes);
+	mutex_unlock(&qrtr_node_lock);
+	ep->node = node;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(qrtr_endpoint_register);
+
+/**
+ * qrtr_endpoint_unregister - unregister endpoint
+ * @ep: endpoint to unregister
+ */
+void qrtr_endpoint_unregister(struct qrtr_endpoint *ep)
+{
+	struct qrtr_node *node = ep->node;
+	struct sockaddr_qrtr src = {AF_QIPCRTR, node->nid, QRTR_PORT_CTRL};
+	struct sockaddr_qrtr dst = {AF_QIPCRTR, qrtr_local_nid, QRTR_PORT_CTRL};
+	struct radix_tree_iter iter;
+	struct qrtr_ctrl_pkt *pkt;
+	struct qrtr_tx_flow *flow;
+	struct sk_buff *skb;
+	unsigned long flags;
+	void __rcu **slot;
+
+	mutex_lock(&node->ep_lock);
+	node->ep = NULL;
+	mutex_unlock(&node->ep_lock);
+
+	/* Notify the local controller about the event */
+	spin_lock_irqsave(&qrtr_nodes_lock, flags);
+	radix_tree_for_each_slot(slot, &qrtr_nodes, &iter, 0) {
+		if (*slot != node)
+			continue;
+		src.sq_node = iter.index;
+		skb = qrtr_alloc_ctrl_packet(&pkt, GFP_ATOMIC);
+		if (skb) {
+			pkt->cmd = cpu_to_le32(QRTR_TYPE_BYE);
+			qrtr_local_enqueue(NULL, skb, QRTR_TYPE_BYE, &src, &dst);
+		}
+	}
+	spin_unlock_irqrestore(&qrtr_nodes_lock, flags);
+
+	/* Wake up any transmitters waiting for resume-tx from the node */
+	mutex_lock(&node->qrtr_tx_lock);
+	radix_tree_for_each_slot(slot, &node->qrtr_tx_flow, &iter, 0) {
+		flow = *slot;
+		wake_up_interruptible_all(&flow->resume_tx);
+	}
+	mutex_unlock(&node->qrtr_tx_lock);
+
+	qrtr_node_release(node);
+	ep->node = NULL;
+}
+EXPORT_SYMBOL_GPL(qrtr_endpoint_unregister);
+
+/* Lookup socket by port.
+ *
+ * Callers must release with qrtr_port_put()
+ */
+static struct qrtr_sock *qrtr_port_lookup(int port)
+{
+	struct qrtr_sock *ipc;
+
+	if (port == QRTR_PORT_CTRL)
+		port = 0;
+
+	rcu_read_lock();
+	ipc = xa_load(&qrtr_ports, port);
+	if (ipc)
+		sock_hold(&ipc->sk);
+	rcu_read_unlock();
+
+	return ipc;
+}
+
+/* Release acquired socket. */
+static void qrtr_port_put(struct qrtr_sock *ipc)
+{
+	sock_put(&ipc->sk);
+}
+
+/* Remove port assignment. */
+static void qrtr_port_remove(struct qrtr_sock *ipc)
+{
+	struct qrtr_ctrl_pkt *pkt;
+	struct sk_buff *skb;
+	int port = ipc->us.sq_port;
+	struct sockaddr_qrtr to;
+
+	to.sq_family = AF_QIPCRTR;
+	to.sq_node = QRTR_NODE_BCAST;
+	to.sq_port = QRTR_PORT_CTRL;
+
+	skb = qrtr_alloc_ctrl_packet(&pkt, GFP_KERNEL);
+	if (skb) {
+		pkt->cmd = cpu_to_le32(QRTR_TYPE_DEL_CLIENT);
+		pkt->client.node = cpu_to_le32(ipc->us.sq_node);
+		pkt->client.port = cpu_to_le32(ipc->us.sq_port);
+
+		skb_set_owner_w(skb, &ipc->sk);
+		qrtr_bcast_enqueue(NULL, skb, QRTR_TYPE_DEL_CLIENT, &ipc->us,
+				   &to);
+	}
+
+	if (port == QRTR_PORT_CTRL)
+		port = 0;
+
+	__sock_put(&ipc->sk);
+
+	xa_erase(&qrtr_ports, port);
+
+	/* Ensure that if qrtr_port_lookup() did enter the RCU read section we
+	 * wait for it to up increment the refcount */
+	synchronize_rcu();
+}
+
+/* Assign port number to socket.
+ *
+ * Specify port in the integer pointed to by port, and it will be adjusted
+ * on return as necesssary.
+ *
+ * Port may be:
+ *   0: Assign ephemeral port in [QRTR_MIN_EPH_SOCKET, QRTR_MAX_EPH_SOCKET]
+ *   <QRTR_MIN_EPH_SOCKET: Specified; requires CAP_NET_ADMIN
+ *   >QRTR_MIN_EPH_SOCKET: Specified; available to all
+ */
+static int qrtr_port_assign(struct qrtr_sock *ipc, int *port)
+{
+	int rc;
+
+	if (!*port) {
+		rc = xa_alloc(&qrtr_ports, port, ipc, QRTR_EPH_PORT_RANGE,
+				GFP_KERNEL);
+	} else if (*port < QRTR_MIN_EPH_SOCKET && !capable(CAP_NET_ADMIN)) {
+		rc = -EACCES;
+	} else if (*port == QRTR_PORT_CTRL) {
+		rc = xa_insert(&qrtr_ports, 0, ipc, GFP_KERNEL);
+	} else {
+		rc = xa_insert(&qrtr_ports, *port, ipc, GFP_KERNEL);
+	}
+
+	if (rc == -EBUSY)
+		return -EADDRINUSE;
+	else if (rc < 0)
+		return rc;
+
+	sock_hold(&ipc->sk);
+
+	return 0;
+}
+
+/* Reset all non-control ports */
+static void qrtr_reset_ports(void)
+{
+	struct qrtr_sock *ipc;
+	unsigned long index;
+
+	rcu_read_lock();
+	xa_for_each_start(&qrtr_ports, index, ipc, 1) {
+		sock_hold(&ipc->sk);
+		ipc->sk.sk_err = ENETRESET;
+		sk_error_report(&ipc->sk);
+		sock_put(&ipc->sk);
+	}
+	rcu_read_unlock();
+}
+
+/* Bind socket to address.
+ *
+ * Socket should be locked upon call.
+ */
+static int __qrtr_bind(struct socket *sock,
+		       const struct sockaddr_qrtr *addr, int zapped)
+{
+	struct qrtr_sock *ipc = qrtr_sk(sock->sk);
+	struct sock *sk = sock->sk;
+	int port;
+	int rc;
+
+	/* rebinding ok */
+	if (!zapped && addr->sq_port == ipc->us.sq_port)
+		return 0;
+
+	port = addr->sq_port;
+	rc = qrtr_port_assign(ipc, &port);
+	if (rc)
+		return rc;
+
+	/* unbind previous, if any */
+	if (!zapped)
+		qrtr_port_remove(ipc);
+	ipc->us.sq_port = port;
+
+	sock_reset_flag(sk, SOCK_ZAPPED);
+
+	/* Notify all open ports about the new controller */
+	if (port == QRTR_PORT_CTRL)
+		qrtr_reset_ports();
+
+	return 0;
+}
+
+/* Auto bind to an ephemeral port. */
+static int qrtr_autobind(struct socket *sock)
+{
+	struct sock *sk = sock->sk;
+	struct sockaddr_qrtr addr;
+
+	if (!sock_flag(sk, SOCK_ZAPPED))
+		return 0;
+
+	addr.sq_family = AF_QIPCRTR;
+	addr.sq_node = qrtr_local_nid;
+	addr.sq_port = 0;
+
+	return __qrtr_bind(sock, &addr, 1);
+}
+
+/* Bind socket to specified sockaddr. */
+static int qrtr_bind(struct socket *sock, struct sockaddr *saddr, int len)
+{
+	DECLARE_SOCKADDR(struct sockaddr_qrtr *, addr, saddr);
+	struct qrtr_sock *ipc = qrtr_sk(sock->sk);
+	struct sock *sk = sock->sk;
+	int rc;
+
+	if (len < sizeof(*addr) || addr->sq_family != AF_QIPCRTR)
+		return -EINVAL;
+
+	if (addr->sq_node != ipc->us.sq_node)
+		return -EINVAL;
+
+	lock_sock(sk);
+	rc = __qrtr_bind(sock, addr, sock_flag(sk, SOCK_ZAPPED));
+	release_sock(sk);
+
+	return rc;
+}
+
+/* Queue packet to local peer socket. */
+static int qrtr_local_enqueue(struct qrtr_node *node, struct sk_buff *skb,
+			      int type, struct sockaddr_qrtr *from,
+			      struct sockaddr_qrtr *to)
+{
+	struct qrtr_sock *ipc;
+	struct qrtr_cb *cb;
+
+	ipc = qrtr_port_lookup(to->sq_port);
+	if (!ipc || &ipc->sk == skb->sk) { /* do not send to self */
+		if (ipc)
+			qrtr_port_put(ipc);
+		kfree_skb(skb);
+		return -ENODEV;
+	}
+
+	cb = (struct qrtr_cb *)skb->cb;
+	cb->src_node = from->sq_node;
+	cb->src_port = from->sq_port;
+
+	if (sock_queue_rcv_skb(&ipc->sk, skb)) {
+		qrtr_port_put(ipc);
+		kfree_skb(skb);
+		return -ENOSPC;
+	}
+
+	qrtr_port_put(ipc);
+
+	return 0;
+}
+
+/* Queue packet for broadcast. */
+static int qrtr_bcast_enqueue(struct qrtr_node *node, struct sk_buff *skb,
+			      int type, struct sockaddr_qrtr *from,
+			      struct sockaddr_qrtr *to)
+{
+	struct sk_buff *skbn;
+
+	mutex_lock(&qrtr_node_lock);
+	list_for_each_entry(node, &qrtr_all_nodes, item) {
+		skbn = skb_clone(skb, GFP_KERNEL);
+		if (!skbn)
+			break;
+		skb_set_owner_w(skbn, skb->sk);
+		qrtr_node_enqueue(node, skbn, type, from, to);
+	}
+	mutex_unlock(&qrtr_node_lock);
+
+	qrtr_local_enqueue(NULL, skb, type, from, to);
+
+	return 0;
+}
+
+static int qrtr_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
+{
+	DECLARE_SOCKADDR(struct sockaddr_qrtr *, addr, msg->msg_name);
+	int (*enqueue_fn)(struct qrtr_node *, struct sk_buff *, int,
+			  struct sockaddr_qrtr *, struct sockaddr_qrtr *);
+	__le32 qrtr_type = cpu_to_le32(QRTR_TYPE_DATA);
+	struct qrtr_sock *ipc = qrtr_sk(sock->sk);
+	struct sock *sk = sock->sk;
+	struct qrtr_node *node;
+	struct sk_buff *skb;
+	size_t plen;
+	u32 type;
+	int rc;
+
+	if (msg->msg_flags & ~(MSG_DONTWAIT))
+		return -EINVAL;
+
+	if (len > 65535)
+		return -EMSGSIZE;
+
+	lock_sock(sk);
+
+	if (addr) {
+		if (msg->msg_namelen < sizeof(*addr)) {
+			release_sock(sk);
+			return -EINVAL;
+		}
+
+		if (addr->sq_family != AF_QIPCRTR) {
+			release_sock(sk);
+			return -EINVAL;
+		}
+
+		rc = qrtr_autobind(sock);
+		if (rc) {
+			release_sock(sk);
+			return rc;
+		}
+	} else if (sk->sk_state == TCP_ESTABLISHED) {
+		addr = &ipc->peer;
+	} else {
+		release_sock(sk);
+		return -ENOTCONN;
+	}
+
+	node = NULL;
+	if (addr->sq_node == QRTR_NODE_BCAST) {
+		if (addr->sq_port != QRTR_PORT_CTRL &&
+		    qrtr_local_nid != QRTR_NODE_BCAST) {
+			release_sock(sk);
+			return -ENOTCONN;
+		}
+		enqueue_fn = qrtr_bcast_enqueue;
+	} else if (addr->sq_node == ipc->us.sq_node) {
+		enqueue_fn = qrtr_local_enqueue;
+	} else {
+		node = qrtr_node_lookup(addr->sq_node);
+		if (!node) {
+			release_sock(sk);
+			return -ECONNRESET;
+		}
+		enqueue_fn = qrtr_node_enqueue;
+	}
+
+	plen = (len + 3) & ~3;
+	skb = sock_alloc_send_skb(sk, plen + QRTR_HDR_MAX_SIZE,
+				  msg->msg_flags & MSG_DONTWAIT, &rc);
+	if (!skb) {
+		rc = -ENOMEM;
+		goto out_node;
+	}
+
+	skb_reserve(skb, QRTR_HDR_MAX_SIZE);
+
+	rc = memcpy_from_msg(skb_put(skb, len), msg, len);
+	if (rc) {
+		kfree_skb(skb);
+		goto out_node;
+	}
+
+	if (ipc->us.sq_port == QRTR_PORT_CTRL) {
+		if (len < 4) {
+			rc = -EINVAL;
+			kfree_skb(skb);
+			goto out_node;
+		}
+
+		/* control messages already require the type as 'command' */
+		skb_copy_bits(skb, 0, &qrtr_type, 4);
+	}
+
+	type = le32_to_cpu(qrtr_type);
+	rc = enqueue_fn(node, skb, type, &ipc->us, addr);
+	if (rc >= 0)
+		rc = len;
+
+out_node:
+	qrtr_node_release(node);
+	release_sock(sk);
+
+	return rc;
+}
+
+static int qrtr_send_resume_tx(struct qrtr_cb *cb)
+{
+	struct sockaddr_qrtr remote = { AF_QIPCRTR, cb->src_node, cb->src_port };
+	struct sockaddr_qrtr local = { AF_QIPCRTR, cb->dst_node, cb->dst_port };
+	struct qrtr_ctrl_pkt *pkt;
+	struct qrtr_node *node;
+	struct sk_buff *skb;
+	int ret;
+
+	node = qrtr_node_lookup(remote.sq_node);
+	if (!node)
+		return -EINVAL;
+
+	skb = qrtr_alloc_ctrl_packet(&pkt, GFP_KERNEL);
+	if (!skb)
+		return -ENOMEM;
+
+	pkt->cmd = cpu_to_le32(QRTR_TYPE_RESUME_TX);
+	pkt->client.node = cpu_to_le32(cb->dst_node);
+	pkt->client.port = cpu_to_le32(cb->dst_port);
+
+	ret = qrtr_node_enqueue(node, skb, QRTR_TYPE_RESUME_TX, &local, &remote);
+
+	qrtr_node_release(node);
+
+	return ret;
+}
+
+static int qrtr_recvmsg(struct socket *sock, struct msghdr *msg,
+			size_t size, int flags)
+{
+	DECLARE_SOCKADDR(struct sockaddr_qrtr *, addr, msg->msg_name);
+	struct sock *sk = sock->sk;
+	struct sk_buff *skb;
+	struct qrtr_cb *cb;
+	int copied, rc;
+
+	lock_sock(sk);
+
+	if (sock_flag(sk, SOCK_ZAPPED)) {
+		release_sock(sk);
+		return -EADDRNOTAVAIL;
+	}
+
+	skb = skb_recv_datagram(sk, flags, &rc);
+	if (!skb) {
+		release_sock(sk);
+		return rc;
+	}
+	cb = (struct qrtr_cb *)skb->cb;
+
+	copied = skb->len;
+	if (copied > size) {
+		copied = size;
+		msg->msg_flags |= MSG_TRUNC;
+	}
+
+	rc = skb_copy_datagram_msg(skb, 0, msg, copied);
+	if (rc < 0)
+		goto out;
+	rc = copied;
+
+	if (addr) {
+		/* There is an anonymous 2-byte hole after sq_family,
+		 * make sure to clear it.
+		 */
+		memset(addr, 0, sizeof(*addr));
+
+		addr->sq_family = AF_QIPCRTR;
+		addr->sq_node = cb->src_node;
+		addr->sq_port = cb->src_port;
+		msg->msg_namelen = sizeof(*addr);
+	}
+
+out:
+	if (cb->confirm_rx)
+		qrtr_send_resume_tx(cb);
+
+	skb_free_datagram(sk, skb);
+	release_sock(sk);
+
+	return rc;
+}
+
+static int qrtr_connect(struct socket *sock, struct sockaddr *saddr,
+			int len, int flags)
+{
+	DECLARE_SOCKADDR(struct sockaddr_qrtr *, addr, saddr);
+	struct qrtr_sock *ipc = qrtr_sk(sock->sk);
+	struct sock *sk = sock->sk;
+	int rc;
+
+	if (len < sizeof(*addr) || addr->sq_family != AF_QIPCRTR)
+		return -EINVAL;
+
+	lock_sock(sk);
+
+	sk->sk_state = TCP_CLOSE;
+	sock->state = SS_UNCONNECTED;
+
+	rc = qrtr_autobind(sock);
+	if (rc) {
+		release_sock(sk);
+		return rc;
+	}
+
+	ipc->peer = *addr;
+	sock->state = SS_CONNECTED;
+	sk->sk_state = TCP_ESTABLISHED;
+
+	release_sock(sk);
+
+	return 0;
+}
+
+static int qrtr_getname(struct socket *sock, struct sockaddr *saddr,
+			int peer)
+{
+	struct qrtr_sock *ipc = qrtr_sk(sock->sk);
+	struct sockaddr_qrtr qaddr;
+	struct sock *sk = sock->sk;
+
+	lock_sock(sk);
+	if (peer) {
+		if (sk->sk_state != TCP_ESTABLISHED) {
+			release_sock(sk);
+			return -ENOTCONN;
+		}
+
+		qaddr = ipc->peer;
+	} else {
+		qaddr = ipc->us;
+	}
+	release_sock(sk);
+
+	qaddr.sq_family = AF_QIPCRTR;
+
+	memcpy(saddr, &qaddr, sizeof(qaddr));
+
+	return sizeof(qaddr);
+}
+
+static int qrtr_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
+{
+	void __user *argp = (void __user *)arg;
+	struct qrtr_sock *ipc = qrtr_sk(sock->sk);
+	struct sock *sk = sock->sk;
+	struct sockaddr_qrtr *sq;
+	struct sk_buff *skb;
+	struct ifreq ifr;
+	long len = 0;
+	int rc = 0;
+
+	lock_sock(sk);
+
+	switch (cmd) {
+	case TIOCOUTQ:
+		len = sk->sk_sndbuf - sk_wmem_alloc_get(sk);
+		if (len < 0)
+			len = 0;
+		rc = put_user(len, (int __user *)argp);
+		break;
+	case TIOCINQ:
+		skb = skb_peek(&sk->sk_receive_queue);
+		if (skb)
+			len = skb->len;
+		rc = put_user(len, (int __user *)argp);
+		break;
+	case SIOCGIFADDR:
+		if (get_user_ifreq(&ifr, NULL, argp)) {
+			rc = -EFAULT;
+			break;
+		}
+
+		sq = (struct sockaddr_qrtr *)&ifr.ifr_addr;
+		*sq = ipc->us;
+		if (put_user_ifreq(&ifr, argp)) {
+			rc = -EFAULT;
+			break;
+		}
+		break;
+	case SIOCADDRT:
+	case SIOCDELRT:
+	case SIOCSIFADDR:
+	case SIOCGIFDSTADDR:
+	case SIOCSIFDSTADDR:
+	case SIOCGIFBRDADDR:
+	case SIOCSIFBRDADDR:
+	case SIOCGIFNETMASK:
+	case SIOCSIFNETMASK:
+		rc = -EINVAL;
+		break;
+	default:
+		rc = -ENOIOCTLCMD;
+		break;
+	}
+
+	release_sock(sk);
+
+	return rc;
+}
+
+static int qrtr_release(struct socket *sock)
+{
+	struct sock *sk = sock->sk;
+	struct qrtr_sock *ipc;
+
+	if (!sk)
+		return 0;
+
+	lock_sock(sk);
+
+	ipc = qrtr_sk(sk);
+	sk->sk_shutdown = SHUTDOWN_MASK;
+	if (!sock_flag(sk, SOCK_DEAD))
+		sk->sk_state_change(sk);
+
+	sock_set_flag(sk, SOCK_DEAD);
+	sock_orphan(sk);
+	sock->sk = NULL;
+
+	if (!sock_flag(sk, SOCK_ZAPPED))
+		qrtr_port_remove(ipc);
+
+	skb_queue_purge(&sk->sk_receive_queue);
+
+	release_sock(sk);
+	sock_put(sk);
+
+	return 0;
+}
+
+static const struct proto_ops qrtr_proto_ops = {
+	.owner		= THIS_MODULE,
+	.family		= AF_QIPCRTR,
+	.bind		= qrtr_bind,
+	.connect	= qrtr_connect,
+	.socketpair	= sock_no_socketpair,
+	.accept		= sock_no_accept,
+	.listen		= sock_no_listen,
+	.sendmsg	= qrtr_sendmsg,
+	.recvmsg	= qrtr_recvmsg,
+	.getname	= qrtr_getname,
+	.ioctl		= qrtr_ioctl,
+	.gettstamp	= sock_gettstamp,
+	.poll		= datagram_poll,
+	.shutdown	= sock_no_shutdown,
+	.release	= qrtr_release,
+	.mmap		= sock_no_mmap,
+	.sendpage	= sock_no_sendpage,
+};
+
+static struct proto qrtr_proto = {
+	.name		= "QIPCRTR",
+	.owner		= THIS_MODULE,
+	.obj_size	= sizeof(struct qrtr_sock),
+};
+
+static int qrtr_create(struct net *net, struct socket *sock,
+		       int protocol, int kern)
+{
+	struct qrtr_sock *ipc;
+	struct sock *sk;
+
+	if (sock->type != SOCK_DGRAM)
+		return -EPROTOTYPE;
+
+	sk = sk_alloc(net, AF_QIPCRTR, GFP_KERNEL, &qrtr_proto, kern);
+	if (!sk)
+		return -ENOMEM;
+
+	sock_set_flag(sk, SOCK_ZAPPED);
+
+	sock_init_data(sock, sk);
+	sock->ops = &qrtr_proto_ops;
+
+	ipc = qrtr_sk(sk);
+	ipc->us.sq_family = AF_QIPCRTR;
+	ipc->us.sq_node = qrtr_local_nid;
+	ipc->us.sq_port = 0;
+
+	return 0;
+}
+
+static const struct net_proto_family qrtr_family = {
+	.owner	= THIS_MODULE,
+	.family	= AF_QIPCRTR,
+	.create	= qrtr_create,
+};
+
+static int __init qrtr_proto_init(void)
+{
+	int rc;
+
+	rc = proto_register(&qrtr_proto, 1);
+	if (rc)
+		return rc;
+
+	rc = sock_register(&qrtr_family);
+	if (rc)
+		goto err_proto;
+
+	rc = qrtr_ns_init();
+	if (rc)
+		goto err_sock;
+
+	return 0;
+
+err_sock:
+	sock_unregister(qrtr_family.family);
+err_proto:
+	proto_unregister(&qrtr_proto);
+	return rc;
+}
+postcore_initcall(qrtr_proto_init);
+
+static void __exit qrtr_proto_fini(void)
+{
+	qrtr_ns_remove();
+	sock_unregister(qrtr_family.family);
+	proto_unregister(&qrtr_proto);
+}
+module_exit(qrtr_proto_fini);
+
+MODULE_DESCRIPTION("Qualcomm IPC-router driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS_NETPROTO(PF_QIPCRTR);