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path: root/drivers/net/thunderbolt.c
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Diffstat (limited to 'drivers/net/thunderbolt.c')
-rw-r--r--drivers/net/thunderbolt.c1362
1 files changed, 1362 insertions, 0 deletions
diff --git a/drivers/net/thunderbolt.c b/drivers/net/thunderbolt.c
new file mode 100644
index 000000000000..1a7bc0bf4598
--- /dev/null
+++ b/drivers/net/thunderbolt.c
@@ -0,0 +1,1362 @@
+/*
+ * Networking over Thunderbolt cable using Apple ThunderboltIP protocol
+ *
+ * Copyright (C) 2017, Intel Corporation
+ * Authors: Amir Levy <amir.jer.levy@intel.com>
+ * Michael Jamet <michael.jamet@intel.com>
+ * Mika Westerberg <mika.westerberg@linux.intel.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/atomic.h>
+#include <linux/highmem.h>
+#include <linux/if_vlan.h>
+#include <linux/jhash.h>
+#include <linux/module.h>
+#include <linux/etherdevice.h>
+#include <linux/rtnetlink.h>
+#include <linux/sizes.h>
+#include <linux/thunderbolt.h>
+#include <linux/uuid.h>
+#include <linux/workqueue.h>
+
+#include <net/ip6_checksum.h>
+
+/* Protocol timeouts in ms */
+#define TBNET_LOGIN_DELAY 4500
+#define TBNET_LOGIN_TIMEOUT 500
+#define TBNET_LOGOUT_TIMEOUT 100
+
+#define TBNET_RING_SIZE 256
+#define TBNET_LOCAL_PATH 0xf
+#define TBNET_LOGIN_RETRIES 60
+#define TBNET_LOGOUT_RETRIES 5
+#define TBNET_MATCH_FRAGS_ID BIT(1)
+#define TBNET_MAX_MTU SZ_64K
+#define TBNET_FRAME_SIZE SZ_4K
+#define TBNET_MAX_PAYLOAD_SIZE \
+ (TBNET_FRAME_SIZE - sizeof(struct thunderbolt_ip_frame_header))
+/* Rx packets need to hold space for skb_shared_info */
+#define TBNET_RX_MAX_SIZE \
+ (TBNET_FRAME_SIZE + SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
+#define TBNET_RX_PAGE_ORDER get_order(TBNET_RX_MAX_SIZE)
+#define TBNET_RX_PAGE_SIZE (PAGE_SIZE << TBNET_RX_PAGE_ORDER)
+
+#define TBNET_L0_PORT_NUM(route) ((route) & GENMASK(5, 0))
+
+/**
+ * struct thunderbolt_ip_frame_header - Header for each Thunderbolt frame
+ * @frame_size: size of the data with the frame
+ * @frame_index: running index on the frames
+ * @frame_id: ID of the frame to match frames to specific packet
+ * @frame_count: how many frames assembles a full packet
+ *
+ * Each data frame passed to the high-speed DMA ring has this header. If
+ * the XDomain network directory announces that %TBNET_MATCH_FRAGS_ID is
+ * supported then @frame_id is filled, otherwise it stays %0.
+ */
+struct thunderbolt_ip_frame_header {
+ u32 frame_size;
+ u16 frame_index;
+ u16 frame_id;
+ u32 frame_count;
+};
+
+enum thunderbolt_ip_frame_pdf {
+ TBIP_PDF_FRAME_START = 1,
+ TBIP_PDF_FRAME_END,
+};
+
+enum thunderbolt_ip_type {
+ TBIP_LOGIN,
+ TBIP_LOGIN_RESPONSE,
+ TBIP_LOGOUT,
+ TBIP_STATUS,
+};
+
+struct thunderbolt_ip_header {
+ u32 route_hi;
+ u32 route_lo;
+ u32 length_sn;
+ uuid_t uuid;
+ uuid_t initiator_uuid;
+ uuid_t target_uuid;
+ u32 type;
+ u32 command_id;
+};
+
+#define TBIP_HDR_LENGTH_MASK GENMASK(5, 0)
+#define TBIP_HDR_SN_MASK GENMASK(28, 27)
+#define TBIP_HDR_SN_SHIFT 27
+
+struct thunderbolt_ip_login {
+ struct thunderbolt_ip_header hdr;
+ u32 proto_version;
+ u32 transmit_path;
+ u32 reserved[4];
+};
+
+#define TBIP_LOGIN_PROTO_VERSION 1
+
+struct thunderbolt_ip_login_response {
+ struct thunderbolt_ip_header hdr;
+ u32 status;
+ u32 receiver_mac[2];
+ u32 receiver_mac_len;
+ u32 reserved[4];
+};
+
+struct thunderbolt_ip_logout {
+ struct thunderbolt_ip_header hdr;
+};
+
+struct thunderbolt_ip_status {
+ struct thunderbolt_ip_header hdr;
+ u32 status;
+};
+
+struct tbnet_stats {
+ u64 tx_packets;
+ u64 rx_packets;
+ u64 tx_bytes;
+ u64 rx_bytes;
+ u64 rx_errors;
+ u64 tx_errors;
+ u64 rx_length_errors;
+ u64 rx_over_errors;
+ u64 rx_crc_errors;
+ u64 rx_missed_errors;
+};
+
+struct tbnet_frame {
+ struct net_device *dev;
+ struct page *page;
+ struct ring_frame frame;
+};
+
+struct tbnet_ring {
+ struct tbnet_frame frames[TBNET_RING_SIZE];
+ unsigned int cons;
+ unsigned int prod;
+ struct tb_ring *ring;
+};
+
+/**
+ * struct tbnet - ThunderboltIP network driver private data
+ * @svc: XDomain service the driver is bound to
+ * @xd: XDomain the service blongs to
+ * @handler: ThunderboltIP configuration protocol handler
+ * @dev: Networking device
+ * @napi: NAPI structure for Rx polling
+ * @stats: Network statistics
+ * @skb: Network packet that is currently processed on Rx path
+ * @command_id: ID used for next configuration protocol packet
+ * @login_sent: ThunderboltIP login message successfully sent
+ * @login_received: ThunderboltIP login message received from the remote
+ * host
+ * @transmit_path: HopID the other end needs to use building the
+ * opposite side path.
+ * @connection_lock: Lock serializing access to @login_sent,
+ * @login_received and @transmit_path.
+ * @login_retries: Number of login retries currently done
+ * @login_work: Worker to send ThunderboltIP login packets
+ * @connected_work: Worker that finalizes the ThunderboltIP connection
+ * setup and enables DMA paths for high speed data
+ * transfers
+ * @rx_hdr: Copy of the currently processed Rx frame. Used when a
+ * network packet consists of multiple Thunderbolt frames.
+ * In host byte order.
+ * @rx_ring: Software ring holding Rx frames
+ * @frame_id: Frame ID use for next Tx packet
+ * (if %TBNET_MATCH_FRAGS_ID is supported in both ends)
+ * @tx_ring: Software ring holding Tx frames
+ */
+struct tbnet {
+ const struct tb_service *svc;
+ struct tb_xdomain *xd;
+ struct tb_protocol_handler handler;
+ struct net_device *dev;
+ struct napi_struct napi;
+ struct tbnet_stats stats;
+ struct sk_buff *skb;
+ atomic_t command_id;
+ bool login_sent;
+ bool login_received;
+ u32 transmit_path;
+ struct mutex connection_lock;
+ int login_retries;
+ struct delayed_work login_work;
+ struct work_struct connected_work;
+ struct thunderbolt_ip_frame_header rx_hdr;
+ struct tbnet_ring rx_ring;
+ atomic_t frame_id;
+ struct tbnet_ring tx_ring;
+};
+
+/* Network property directory UUID: c66189ca-1cce-4195-bdb8-49592e5f5a4f */
+static const uuid_t tbnet_dir_uuid =
+ UUID_INIT(0xc66189ca, 0x1cce, 0x4195,
+ 0xbd, 0xb8, 0x49, 0x59, 0x2e, 0x5f, 0x5a, 0x4f);
+
+/* ThunderboltIP protocol UUID: 798f589e-3616-8a47-97c6-5664a920c8dd */
+static const uuid_t tbnet_svc_uuid =
+ UUID_INIT(0x798f589e, 0x3616, 0x8a47,
+ 0x97, 0xc6, 0x56, 0x64, 0xa9, 0x20, 0xc8, 0xdd);
+
+static struct tb_property_dir *tbnet_dir;
+
+static void tbnet_fill_header(struct thunderbolt_ip_header *hdr, u64 route,
+ u8 sequence, const uuid_t *initiator_uuid, const uuid_t *target_uuid,
+ enum thunderbolt_ip_type type, size_t size, u32 command_id)
+{
+ u32 length_sn;
+
+ /* Length does not include route_hi/lo and length_sn fields */
+ length_sn = (size - 3 * 4) / 4;
+ length_sn |= (sequence << TBIP_HDR_SN_SHIFT) & TBIP_HDR_SN_MASK;
+
+ hdr->route_hi = upper_32_bits(route);
+ hdr->route_lo = lower_32_bits(route);
+ hdr->length_sn = length_sn;
+ uuid_copy(&hdr->uuid, &tbnet_svc_uuid);
+ uuid_copy(&hdr->initiator_uuid, initiator_uuid);
+ uuid_copy(&hdr->target_uuid, target_uuid);
+ hdr->type = type;
+ hdr->command_id = command_id;
+}
+
+static int tbnet_login_response(struct tbnet *net, u64 route, u8 sequence,
+ u32 command_id)
+{
+ struct thunderbolt_ip_login_response reply;
+ struct tb_xdomain *xd = net->xd;
+
+ memset(&reply, 0, sizeof(reply));
+ tbnet_fill_header(&reply.hdr, route, sequence, xd->local_uuid,
+ xd->remote_uuid, TBIP_LOGIN_RESPONSE, sizeof(reply),
+ command_id);
+ memcpy(reply.receiver_mac, net->dev->dev_addr, ETH_ALEN);
+ reply.receiver_mac_len = ETH_ALEN;
+
+ return tb_xdomain_response(xd, &reply, sizeof(reply),
+ TB_CFG_PKG_XDOMAIN_RESP);
+}
+
+static int tbnet_login_request(struct tbnet *net, u8 sequence)
+{
+ struct thunderbolt_ip_login_response reply;
+ struct thunderbolt_ip_login request;
+ struct tb_xdomain *xd = net->xd;
+
+ memset(&request, 0, sizeof(request));
+ tbnet_fill_header(&request.hdr, xd->route, sequence, xd->local_uuid,
+ xd->remote_uuid, TBIP_LOGIN, sizeof(request),
+ atomic_inc_return(&net->command_id));
+
+ request.proto_version = TBIP_LOGIN_PROTO_VERSION;
+ request.transmit_path = TBNET_LOCAL_PATH;
+
+ return tb_xdomain_request(xd, &request, sizeof(request),
+ TB_CFG_PKG_XDOMAIN_RESP, &reply,
+ sizeof(reply), TB_CFG_PKG_XDOMAIN_RESP,
+ TBNET_LOGIN_TIMEOUT);
+}
+
+static int tbnet_logout_response(struct tbnet *net, u64 route, u8 sequence,
+ u32 command_id)
+{
+ struct thunderbolt_ip_status reply;
+ struct tb_xdomain *xd = net->xd;
+
+ memset(&reply, 0, sizeof(reply));
+ tbnet_fill_header(&reply.hdr, route, sequence, xd->local_uuid,
+ xd->remote_uuid, TBIP_STATUS, sizeof(reply),
+ atomic_inc_return(&net->command_id));
+ return tb_xdomain_response(xd, &reply, sizeof(reply),
+ TB_CFG_PKG_XDOMAIN_RESP);
+}
+
+static int tbnet_logout_request(struct tbnet *net)
+{
+ struct thunderbolt_ip_logout request;
+ struct thunderbolt_ip_status reply;
+ struct tb_xdomain *xd = net->xd;
+
+ memset(&request, 0, sizeof(request));
+ tbnet_fill_header(&request.hdr, xd->route, 0, xd->local_uuid,
+ xd->remote_uuid, TBIP_LOGOUT, sizeof(request),
+ atomic_inc_return(&net->command_id));
+
+ return tb_xdomain_request(xd, &request, sizeof(request),
+ TB_CFG_PKG_XDOMAIN_RESP, &reply,
+ sizeof(reply), TB_CFG_PKG_XDOMAIN_RESP,
+ TBNET_LOGOUT_TIMEOUT);
+}
+
+static void start_login(struct tbnet *net)
+{
+ mutex_lock(&net->connection_lock);
+ net->login_sent = false;
+ net->login_received = false;
+ mutex_unlock(&net->connection_lock);
+
+ queue_delayed_work(system_long_wq, &net->login_work,
+ msecs_to_jiffies(1000));
+}
+
+static void stop_login(struct tbnet *net)
+{
+ cancel_delayed_work_sync(&net->login_work);
+ cancel_work_sync(&net->connected_work);
+}
+
+static inline unsigned int tbnet_frame_size(const struct tbnet_frame *tf)
+{
+ return tf->frame.size ? : TBNET_FRAME_SIZE;
+}
+
+static void tbnet_free_buffers(struct tbnet_ring *ring)
+{
+ unsigned int i;
+
+ for (i = 0; i < TBNET_RING_SIZE; i++) {
+ struct device *dma_dev = tb_ring_dma_device(ring->ring);
+ struct tbnet_frame *tf = &ring->frames[i];
+ enum dma_data_direction dir;
+ unsigned int order;
+ size_t size;
+
+ if (!tf->page)
+ continue;
+
+ if (ring->ring->is_tx) {
+ dir = DMA_TO_DEVICE;
+ order = 0;
+ size = tbnet_frame_size(tf);
+ } else {
+ dir = DMA_FROM_DEVICE;
+ order = TBNET_RX_PAGE_ORDER;
+ size = TBNET_RX_PAGE_SIZE;
+ }
+
+ if (tf->frame.buffer_phy)
+ dma_unmap_page(dma_dev, tf->frame.buffer_phy, size,
+ dir);
+
+ __free_pages(tf->page, order);
+ tf->page = NULL;
+ }
+
+ ring->cons = 0;
+ ring->prod = 0;
+}
+
+static void tbnet_tear_down(struct tbnet *net, bool send_logout)
+{
+ netif_carrier_off(net->dev);
+ netif_stop_queue(net->dev);
+
+ stop_login(net);
+
+ mutex_lock(&net->connection_lock);
+
+ if (net->login_sent && net->login_received) {
+ int retries = TBNET_LOGOUT_RETRIES;
+
+ while (send_logout && retries-- > 0) {
+ int ret = tbnet_logout_request(net);
+ if (ret != -ETIMEDOUT)
+ break;
+ }
+
+ tb_ring_stop(net->rx_ring.ring);
+ tb_ring_stop(net->tx_ring.ring);
+ tbnet_free_buffers(&net->rx_ring);
+ tbnet_free_buffers(&net->tx_ring);
+
+ if (tb_xdomain_disable_paths(net->xd))
+ netdev_warn(net->dev, "failed to disable DMA paths\n");
+ }
+
+ net->login_retries = 0;
+ net->login_sent = false;
+ net->login_received = false;
+
+ mutex_unlock(&net->connection_lock);
+}
+
+static int tbnet_handle_packet(const void *buf, size_t size, void *data)
+{
+ const struct thunderbolt_ip_login *pkg = buf;
+ struct tbnet *net = data;
+ u32 command_id;
+ int ret = 0;
+ u8 sequence;
+ u64 route;
+
+ /* Make sure the packet is for us */
+ if (size < sizeof(struct thunderbolt_ip_header))
+ return 0;
+ if (!uuid_equal(&pkg->hdr.initiator_uuid, net->xd->remote_uuid))
+ return 0;
+ if (!uuid_equal(&pkg->hdr.target_uuid, net->xd->local_uuid))
+ return 0;
+
+ route = ((u64)pkg->hdr.route_hi << 32) | pkg->hdr.route_lo;
+ route &= ~BIT_ULL(63);
+ if (route != net->xd->route)
+ return 0;
+
+ sequence = pkg->hdr.length_sn & TBIP_HDR_SN_MASK;
+ sequence >>= TBIP_HDR_SN_SHIFT;
+ command_id = pkg->hdr.command_id;
+
+ switch (pkg->hdr.type) {
+ case TBIP_LOGIN:
+ if (!netif_running(net->dev))
+ break;
+
+ ret = tbnet_login_response(net, route, sequence,
+ pkg->hdr.command_id);
+ if (!ret) {
+ mutex_lock(&net->connection_lock);
+ net->login_received = true;
+ net->transmit_path = pkg->transmit_path;
+
+ /* If we reached the number of max retries or
+ * previous logout, schedule another round of
+ * login retries
+ */
+ if (net->login_retries >= TBNET_LOGIN_RETRIES ||
+ !net->login_sent) {
+ net->login_retries = 0;
+ queue_delayed_work(system_long_wq,
+ &net->login_work, 0);
+ }
+ mutex_unlock(&net->connection_lock);
+
+ queue_work(system_long_wq, &net->connected_work);
+ }
+ break;
+
+ case TBIP_LOGOUT:
+ ret = tbnet_logout_response(net, route, sequence, command_id);
+ if (!ret)
+ tbnet_tear_down(net, false);
+ break;
+
+ default:
+ return 0;
+ }
+
+ if (ret)
+ netdev_warn(net->dev, "failed to send ThunderboltIP response\n");
+
+ return 1;
+}
+
+static unsigned int tbnet_available_buffers(const struct tbnet_ring *ring)
+{
+ return ring->prod - ring->cons;
+}
+
+static int tbnet_alloc_rx_buffers(struct tbnet *net, unsigned int nbuffers)
+{
+ struct tbnet_ring *ring = &net->rx_ring;
+ int ret;
+
+ while (nbuffers--) {
+ struct device *dma_dev = tb_ring_dma_device(ring->ring);
+ unsigned int index = ring->prod & (TBNET_RING_SIZE - 1);
+ struct tbnet_frame *tf = &ring->frames[index];
+ dma_addr_t dma_addr;
+
+ if (tf->page)
+ break;
+
+ /* Allocate page (order > 0) so that it can hold maximum
+ * ThunderboltIP frame (4kB) and the additional room for
+ * SKB shared info required by build_skb().
+ */
+ tf->page = dev_alloc_pages(TBNET_RX_PAGE_ORDER);
+ if (!tf->page) {
+ ret = -ENOMEM;
+ goto err_free;
+ }
+
+ dma_addr = dma_map_page(dma_dev, tf->page, 0,
+ TBNET_RX_PAGE_SIZE, DMA_FROM_DEVICE);
+ if (dma_mapping_error(dma_dev, dma_addr)) {
+ ret = -ENOMEM;
+ goto err_free;
+ }
+
+ tf->frame.buffer_phy = dma_addr;
+ tf->dev = net->dev;
+
+ tb_ring_rx(ring->ring, &tf->frame);
+
+ ring->prod++;
+ }
+
+ return 0;
+
+err_free:
+ tbnet_free_buffers(ring);
+ return ret;
+}
+
+static struct tbnet_frame *tbnet_get_tx_buffer(struct tbnet *net)
+{
+ struct tbnet_ring *ring = &net->tx_ring;
+ struct tbnet_frame *tf;
+ unsigned int index;
+
+ if (!tbnet_available_buffers(ring))
+ return NULL;
+
+ index = ring->cons++ & (TBNET_RING_SIZE - 1);
+
+ tf = &ring->frames[index];
+ tf->frame.size = 0;
+ tf->frame.buffer_phy = 0;
+
+ return tf;
+}
+
+static void tbnet_tx_callback(struct tb_ring *ring, struct ring_frame *frame,
+ bool canceled)
+{
+ struct tbnet_frame *tf = container_of(frame, typeof(*tf), frame);
+ struct device *dma_dev = tb_ring_dma_device(ring);
+ struct tbnet *net = netdev_priv(tf->dev);
+
+ dma_unmap_page(dma_dev, tf->frame.buffer_phy, tbnet_frame_size(tf),
+ DMA_TO_DEVICE);
+
+ /* Return buffer to the ring */
+ net->tx_ring.prod++;
+
+ if (tbnet_available_buffers(&net->tx_ring) >= TBNET_RING_SIZE / 2)
+ netif_wake_queue(net->dev);
+}
+
+static int tbnet_alloc_tx_buffers(struct tbnet *net)
+{
+ struct tbnet_ring *ring = &net->tx_ring;
+ unsigned int i;
+
+ for (i = 0; i < TBNET_RING_SIZE; i++) {
+ struct tbnet_frame *tf = &ring->frames[i];
+
+ tf->page = alloc_page(GFP_KERNEL);
+ if (!tf->page) {
+ tbnet_free_buffers(ring);
+ return -ENOMEM;
+ }
+
+ tf->dev = net->dev;
+ tf->frame.callback = tbnet_tx_callback;
+ tf->frame.sof = TBIP_PDF_FRAME_START;
+ tf->frame.eof = TBIP_PDF_FRAME_END;
+ }
+
+ ring->cons = 0;
+ ring->prod = TBNET_RING_SIZE - 1;
+
+ return 0;
+}
+
+static void tbnet_connected_work(struct work_struct *work)
+{
+ struct tbnet *net = container_of(work, typeof(*net), connected_work);
+ bool connected;
+ int ret;
+
+ if (netif_carrier_ok(net->dev))
+ return;
+
+ mutex_lock(&net->connection_lock);
+ connected = net->login_sent && net->login_received;
+ mutex_unlock(&net->connection_lock);
+
+ if (!connected)
+ return;
+
+ /* Both logins successful so enable the high-speed DMA paths and
+ * start the network device queue.
+ */
+ ret = tb_xdomain_enable_paths(net->xd, TBNET_LOCAL_PATH,
+ net->rx_ring.ring->hop,
+ net->transmit_path,
+ net->tx_ring.ring->hop);
+ if (ret) {
+ netdev_err(net->dev, "failed to enable DMA paths\n");
+ return;
+ }
+
+ tb_ring_start(net->tx_ring.ring);
+ tb_ring_start(net->rx_ring.ring);
+
+ ret = tbnet_alloc_rx_buffers(net, TBNET_RING_SIZE);
+ if (ret)
+ goto err_stop_rings;
+
+ ret = tbnet_alloc_tx_buffers(net);
+ if (ret)
+ goto err_free_rx_buffers;
+
+ netif_carrier_on(net->dev);
+ netif_start_queue(net->dev);
+ return;
+
+err_free_rx_buffers:
+ tbnet_free_buffers(&net->rx_ring);
+err_stop_rings:
+ tb_ring_stop(net->rx_ring.ring);
+ tb_ring_stop(net->tx_ring.ring);
+}
+
+static void tbnet_login_work(struct work_struct *work)
+{
+ struct tbnet *net = container_of(work, typeof(*net), login_work.work);
+ unsigned long delay = msecs_to_jiffies(TBNET_LOGIN_DELAY);
+ int ret;
+
+ if (netif_carrier_ok(net->dev))
+ return;
+
+ ret = tbnet_login_request(net, net->login_retries % 4);
+ if (ret) {
+ if (net->login_retries++ < TBNET_LOGIN_RETRIES) {
+ queue_delayed_work(system_long_wq, &net->login_work,
+ delay);
+ } else {
+ netdev_info(net->dev, "ThunderboltIP login timed out\n");
+ }
+ } else {
+ net->login_retries = 0;
+
+ mutex_lock(&net->connection_lock);
+ net->login_sent = true;
+ mutex_unlock(&net->connection_lock);
+
+ queue_work(system_long_wq, &net->connected_work);
+ }
+}
+
+static bool tbnet_check_frame(struct tbnet *net, const struct tbnet_frame *tf,
+ const struct thunderbolt_ip_frame_header *hdr)
+{
+ u32 frame_id, frame_count, frame_size, frame_index;
+ unsigned int size;
+
+ if (tf->frame.flags & RING_DESC_CRC_ERROR) {
+ net->stats.rx_crc_errors++;
+ return false;
+ } else if (tf->frame.flags & RING_DESC_BUFFER_OVERRUN) {
+ net->stats.rx_over_errors++;
+ return false;
+ }
+
+ /* Should be greater than just header i.e. contains data */
+ size = tbnet_frame_size(tf);
+ if (size <= sizeof(*hdr)) {
+ net->stats.rx_length_errors++;
+ return false;
+ }
+
+ frame_count = le32_to_cpu(hdr->frame_count);
+ frame_size = le32_to_cpu(hdr->frame_size);
+ frame_index = le16_to_cpu(hdr->frame_index);
+ frame_id = le16_to_cpu(hdr->frame_id);
+
+ if ((frame_size > size - sizeof(*hdr)) || !frame_size) {
+ net->stats.rx_length_errors++;
+ return false;
+ }
+
+ /* In case we're in the middle of packet, validate the frame
+ * header based on first fragment of the packet.
+ */
+ if (net->skb && net->rx_hdr.frame_count) {
+ /* Check the frame count fits the count field */
+ if (frame_count != net->rx_hdr.frame_count) {
+ net->stats.rx_length_errors++;
+ return false;
+ }
+
+ /* Check the frame identifiers are incremented correctly,
+ * and id is matching.
+ */
+ if (frame_index != net->rx_hdr.frame_index + 1 ||
+ frame_id != net->rx_hdr.frame_id) {
+ net->stats.rx_missed_errors++;
+ return false;
+ }
+
+ if (net->skb->len + frame_size > TBNET_MAX_MTU) {
+ net->stats.rx_length_errors++;
+ return false;
+ }
+
+ return true;
+ }
+
+ /* Start of packet, validate the frame header */
+ if (frame_count == 0 || frame_count > TBNET_RING_SIZE / 4) {
+ net->stats.rx_length_errors++;
+ return false;
+ }
+ if (frame_index != 0) {
+ net->stats.rx_missed_errors++;
+ return false;
+ }
+
+ return true;
+}
+
+static int tbnet_poll(struct napi_struct *napi, int budget)
+{
+ struct tbnet *net = container_of(napi, struct tbnet, napi);
+ unsigned int cleaned_count = tbnet_available_buffers(&net->rx_ring);
+ struct device *dma_dev = tb_ring_dma_device(net->rx_ring.ring);
+ unsigned int rx_packets = 0;
+
+ while (rx_packets < budget) {
+ const struct thunderbolt_ip_frame_header *hdr;
+ unsigned int hdr_size = sizeof(*hdr);
+ struct sk_buff *skb = NULL;
+ struct ring_frame *frame;
+ struct tbnet_frame *tf;
+ struct page *page;
+ bool last = true;
+ u32 frame_size;
+
+ /* Return some buffers to hardware, one at a time is too
+ * slow so allocate MAX_SKB_FRAGS buffers at the same
+ * time.
+ */
+ if (cleaned_count >= MAX_SKB_FRAGS) {
+ tbnet_alloc_rx_buffers(net, cleaned_count);
+ cleaned_count = 0;
+ }
+
+ frame = tb_ring_poll(net->rx_ring.ring);
+ if (!frame)
+ break;
+
+ dma_unmap_page(dma_dev, frame->buffer_phy,
+ TBNET_RX_PAGE_SIZE, DMA_FROM_DEVICE);
+
+ tf = container_of(frame, typeof(*tf), frame);
+
+ page = tf->page;
+ tf->page = NULL;
+ net->rx_ring.cons++;
+ cleaned_count++;
+
+ hdr = page_address(page);
+ if (!tbnet_check_frame(net, tf, hdr)) {
+ __free_pages(page, TBNET_RX_PAGE_ORDER);
+ dev_kfree_skb_any(net->skb);
+ net->skb = NULL;
+ continue;
+ }
+
+ frame_size = le32_to_cpu(hdr->frame_size);
+
+ skb = net->skb;
+ if (!skb) {
+ skb = build_skb(page_address(page),
+ TBNET_RX_PAGE_SIZE);
+ if (!skb) {
+ __free_pages(page, TBNET_RX_PAGE_ORDER);
+ net->stats.rx_errors++;
+ break;
+ }
+
+ skb_reserve(skb, hdr_size);
+ skb_put(skb, frame_size);
+
+ net->skb = skb;
+ } else {
+ skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags,
+ page, hdr_size, frame_size,
+ TBNET_RX_PAGE_SIZE - hdr_size);
+ }
+
+ net->rx_hdr.frame_size = frame_size;
+ net->rx_hdr.frame_count = le32_to_cpu(hdr->frame_count);
+ net->rx_hdr.frame_index = le16_to_cpu(hdr->frame_index);
+ net->rx_hdr.frame_id = le16_to_cpu(hdr->frame_id);
+ last = net->rx_hdr.frame_index == net->rx_hdr.frame_count - 1;
+
+ rx_packets++;
+ net->stats.rx_bytes += frame_size;
+
+ if (last) {
+ skb->protocol = eth_type_trans(skb, net->dev);
+ napi_gro_receive(&net->napi, skb);
+ net->skb = NULL;
+ }
+ }
+
+ net->stats.rx_packets += rx_packets;
+
+ if (cleaned_count)
+ tbnet_alloc_rx_buffers(net, cleaned_count);
+
+ if (rx_packets >= budget)
+ return budget;
+
+ napi_complete_done(napi, rx_packets);
+ /* Re-enable the ring interrupt */
+ tb_ring_poll_complete(net->rx_ring.ring);
+
+ return rx_packets;
+}
+
+static void tbnet_start_poll(void *data)
+{
+ struct tbnet *net = data;
+
+ napi_schedule(&net->napi);
+}
+
+static int tbnet_open(struct net_device *dev)
+{
+ struct tbnet *net = netdev_priv(dev);
+ struct tb_xdomain *xd = net->xd;
+ u16 sof_mask, eof_mask;
+ struct tb_ring *ring;
+
+ netif_carrier_off(dev);
+
+ ring = tb_ring_alloc_tx(xd->tb->nhi, -1, TBNET_RING_SIZE,
+ RING_FLAG_FRAME);
+ if (!ring) {
+ netdev_err(dev, "failed to allocate Tx ring\n");
+ return -ENOMEM;
+ }
+ net->tx_ring.ring = ring;
+
+ sof_mask = BIT(TBIP_PDF_FRAME_START);
+ eof_mask = BIT(TBIP_PDF_FRAME_END);
+
+ ring = tb_ring_alloc_rx(xd->tb->nhi, -1, TBNET_RING_SIZE,
+ RING_FLAG_FRAME | RING_FLAG_E2E, sof_mask,
+ eof_mask, tbnet_start_poll, net);
+ if (!ring) {
+ netdev_err(dev, "failed to allocate Rx ring\n");
+ tb_ring_free(net->tx_ring.ring);
+ net->tx_ring.ring = NULL;
+ return -ENOMEM;
+ }
+ net->rx_ring.ring = ring;
+
+ napi_enable(&net->napi);
+ start_login(net);
+
+ return 0;
+}
+
+static int tbnet_stop(struct net_device *dev)
+{
+ struct tbnet *net = netdev_priv(dev);
+
+ napi_disable(&net->napi);
+
+ tbnet_tear_down(net, true);
+
+ tb_ring_free(net->rx_ring.ring);
+ net->rx_ring.ring = NULL;
+ tb_ring_free(net->tx_ring.ring);
+ net->tx_ring.ring = NULL;
+
+ return 0;
+}
+
+static bool tbnet_xmit_map(struct device *dma_dev, struct tbnet_frame *tf)
+{
+ dma_addr_t dma_addr;
+
+ dma_addr = dma_map_page(dma_dev, tf->page, 0, tbnet_frame_size(tf),
+ DMA_TO_DEVICE);
+ if (dma_mapping_error(dma_dev, dma_addr))
+ return false;
+
+ tf->frame.buffer_phy = dma_addr;
+ return true;
+}
+
+static bool tbnet_xmit_csum_and_map(struct tbnet *net, struct sk_buff *skb,
+ struct tbnet_frame **frames, u32 frame_count)
+{
+ struct thunderbolt_ip_frame_header *hdr = page_address(frames[0]->page);
+ struct device *dma_dev = tb_ring_dma_device(net->tx_ring.ring);
+ __wsum wsum = htonl(skb->len - skb_transport_offset(skb));
+ unsigned int i, len, offset = skb_transport_offset(skb);
+ __be16 protocol = skb->protocol;
+ void *data = skb->data;
+ void *dest = hdr + 1;
+ __sum16 *tucso;
+
+ if (skb->ip_summed != CHECKSUM_PARTIAL) {
+ /* No need to calculate checksum so we just update the
+ * total frame count and map the frames for DMA.
+ */
+ for (i = 0; i < frame_count; i++) {
+ hdr = page_address(frames[i]->page);
+ hdr->frame_count = cpu_to_le32(frame_count);
+ if (!tbnet_xmit_map(dma_dev, frames[i]))
+ goto err_unmap;
+ }
+
+ return true;
+ }
+
+ if (protocol == htons(ETH_P_8021Q)) {
+ struct vlan_hdr *vhdr, vh;
+
+ vhdr = skb_header_pointer(skb, ETH_HLEN, sizeof(vh), &vh);
+ if (!vhdr)
+ return false;
+
+ protocol = vhdr->h_vlan_encapsulated_proto;
+ }
+
+ /* Data points on the beginning of packet.
+ * Check is the checksum absolute place in the packet.
+ * ipcso will update IP checksum.
+ * tucso will update TCP/UPD checksum.
+ */
+ if (protocol == htons(ETH_P_IP)) {
+ __sum16 *ipcso = dest + ((void *)&(ip_hdr(skb)->check) - data);
+
+ *ipcso = 0;
+ *ipcso = ip_fast_csum(dest + skb_network_offset(skb),
+ ip_hdr(skb)->ihl);
+
+ if (ip_hdr(skb)->protocol == IPPROTO_TCP)
+ tucso = dest + ((void *)&(tcp_hdr(skb)->check) - data);
+ else if (ip_hdr(skb)->protocol == IPPROTO_UDP)
+ tucso = dest + ((void *)&(udp_hdr(skb)->check) - data);
+ else
+ return false;
+
+ *tucso = ~csum_tcpudp_magic(ip_hdr(skb)->saddr,
+ ip_hdr(skb)->daddr, 0,
+ ip_hdr(skb)->protocol, 0);
+ } else if (skb_is_gso_v6(skb)) {
+ tucso = dest + ((void *)&(tcp_hdr(skb)->check) - data);
+ *tucso = ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
+ &ipv6_hdr(skb)->daddr, 0,
+ IPPROTO_TCP, 0);
+ return false;
+ } else if (protocol == htons(ETH_P_IPV6)) {
+ tucso = dest + skb_checksum_start_offset(skb) + skb->csum_offset;
+ *tucso = ~csum_ipv6_magic(&ipv6_hdr(skb)->saddr,
+ &ipv6_hdr(skb)->daddr, 0,
+ ipv6_hdr(skb)->nexthdr, 0);
+ } else {
+ return false;
+ }
+
+ /* First frame was headers, rest of the frames contain data.
+ * Calculate checksum over each frame.
+ */
+ for (i = 0; i < frame_count; i++) {
+ hdr = page_address(frames[i]->page);
+ dest = (void *)(hdr + 1) + offset;
+ len = le32_to_cpu(hdr->frame_size) - offset;
+ wsum = csum_partial(dest, len, wsum);
+ hdr->frame_count = cpu_to_le32(frame_count);
+
+ offset = 0;
+ }
+
+ *tucso = csum_fold(wsum);
+
+ /* Checksum is finally calculated and we don't touch the memory
+ * anymore, so DMA map the frames now.
+ */
+ for (i = 0; i < frame_count; i++) {
+ if (!tbnet_xmit_map(dma_dev, frames[i]))
+ goto err_unmap;
+ }
+
+ return true;
+
+err_unmap:
+ while (i--)
+ dma_unmap_page(dma_dev, frames[i]->frame.buffer_phy,
+ tbnet_frame_size(frames[i]), DMA_TO_DEVICE);
+
+ return false;
+}
+
+static void *tbnet_kmap_frag(struct sk_buff *skb, unsigned int frag_num,
+ unsigned int *len)
+{
+ const skb_frag_t *frag = &skb_shinfo(skb)->frags[frag_num];
+
+ *len = skb_frag_size(frag);
+ return kmap_atomic(skb_frag_page(frag)) + frag->page_offset;
+}
+
+static netdev_tx_t tbnet_start_xmit(struct sk_buff *skb,
+ struct net_device *dev)
+{
+ struct tbnet *net = netdev_priv(dev);
+ struct tbnet_frame *frames[MAX_SKB_FRAGS];
+ u16 frame_id = atomic_read(&net->frame_id);
+ struct thunderbolt_ip_frame_header *hdr;
+ unsigned int len = skb_headlen(skb);
+ unsigned int data_len = skb->len;
+ unsigned int nframes, i;
+ unsigned int frag = 0;
+ void *src = skb->data;
+ u32 frame_index = 0;
+ bool unmap = false;
+ void *dest;
+
+ nframes = DIV_ROUND_UP(data_len, TBNET_MAX_PAYLOAD_SIZE);
+ if (tbnet_available_buffers(&net->tx_ring) < nframes) {
+ netif_stop_queue(net->dev);
+ return NETDEV_TX_BUSY;
+ }
+
+ frames[frame_index] = tbnet_get_tx_buffer(net);
+ if (!frames[frame_index])
+ goto err_drop;
+
+ hdr = page_address(frames[frame_index]->page);
+ dest = hdr + 1;
+
+ /* If overall packet is bigger than the frame data size */
+ while (data_len > TBNET_MAX_PAYLOAD_SIZE) {
+ unsigned int size_left = TBNET_MAX_PAYLOAD_SIZE;
+
+ hdr->frame_size = cpu_to_le32(TBNET_MAX_PAYLOAD_SIZE);
+ hdr->frame_index = cpu_to_le16(frame_index);
+ hdr->frame_id = cpu_to_le16(frame_id);
+
+ do {
+ if (len > size_left) {
+ /* Copy data onto Tx buffer data with
+ * full frame size then break and go to
+ * next frame
+ */
+ memcpy(dest, src, size_left);
+ len -= size_left;
+ dest += size_left;
+ src += size_left;
+ break;
+ }
+
+ memcpy(dest, src, len);
+ size_left -= len;
+ dest += len;
+
+ if (unmap) {
+ kunmap_atomic(src);
+ unmap = false;
+ }
+
+ /* Ensure all fragments have been processed */
+ if (frag < skb_shinfo(skb)->nr_frags) {
+ /* Map and then unmap quickly */
+ src = tbnet_kmap_frag(skb, frag++, &len);
+ unmap = true;
+ } else if (unlikely(size_left > 0)) {
+ goto err_drop;
+ }
+ } while (size_left > 0);
+
+ data_len -= TBNET_MAX_PAYLOAD_SIZE;
+ frame_index++;
+
+ frames[frame_index] = tbnet_get_tx_buffer(net);
+ if (!frames[frame_index])
+ goto err_drop;
+
+ hdr = page_address(frames[frame_index]->page);
+ dest = hdr + 1;
+ }
+
+ hdr->frame_size = cpu_to_le32(data_len);
+ hdr->frame_index = cpu_to_le16(frame_index);
+ hdr->frame_id = cpu_to_le16(frame_id);
+
+ frames[frame_index]->frame.size = data_len + sizeof(*hdr);
+
+ /* In case the remaining data_len is smaller than a frame */
+ while (len < data_len) {
+ memcpy(dest, src, len);
+ data_len -= len;
+ dest += len;
+
+ if (unmap) {
+ kunmap_atomic(src);
+ unmap = false;
+ }
+
+ if (frag < skb_shinfo(skb)->nr_frags) {
+ src = tbnet_kmap_frag(skb, frag++, &len);
+ unmap = true;
+ } else if (unlikely(data_len > 0)) {
+ goto err_drop;
+ }
+ }
+
+ memcpy(dest, src, data_len);
+
+ if (unmap)
+ kunmap_atomic(src);
+
+ if (!tbnet_xmit_csum_and_map(net, skb, frames, frame_index + 1))
+ goto err_drop;
+
+ for (i = 0; i < frame_index + 1; i++)
+ tb_ring_tx(net->tx_ring.ring, &frames[i]->frame);
+
+ if (net->svc->prtcstns & TBNET_MATCH_FRAGS_ID)
+ atomic_inc(&net->frame_id);
+
+ net->stats.tx_packets++;
+ net->stats.tx_bytes += skb->len;
+
+ dev_consume_skb_any(skb);
+
+ return NETDEV_TX_OK;
+
+err_drop:
+ /* We can re-use the buffers */
+ net->tx_ring.cons -= frame_index;
+
+ dev_kfree_skb_any(skb);
+ net->stats.tx_errors++;
+
+ return NETDEV_TX_OK;
+}
+
+static void tbnet_get_stats64(struct net_device *dev,
+ struct rtnl_link_stats64 *stats)
+{
+ struct tbnet *net = netdev_priv(dev);
+
+ stats->tx_packets = net->stats.tx_packets;
+ stats->rx_packets = net->stats.rx_packets;
+ stats->tx_bytes = net->stats.tx_bytes;
+ stats->rx_bytes = net->stats.rx_bytes;
+ stats->rx_errors = net->stats.rx_errors + net->stats.rx_length_errors +
+ net->stats.rx_over_errors + net->stats.rx_crc_errors +
+ net->stats.rx_missed_errors;
+ stats->tx_errors = net->stats.tx_errors;
+ stats->rx_length_errors = net->stats.rx_length_errors;
+ stats->rx_over_errors = net->stats.rx_over_errors;
+ stats->rx_crc_errors = net->stats.rx_crc_errors;
+ stats->rx_missed_errors = net->stats.rx_missed_errors;
+}
+
+static const struct net_device_ops tbnet_netdev_ops = {
+ .ndo_open = tbnet_open,
+ .ndo_stop = tbnet_stop,
+ .ndo_start_xmit = tbnet_start_xmit,
+ .ndo_get_stats64 = tbnet_get_stats64,
+};
+
+static void tbnet_generate_mac(struct net_device *dev)
+{
+ const struct tbnet *net = netdev_priv(dev);
+ const struct tb_xdomain *xd = net->xd;
+ u8 phy_port;
+ u32 hash;
+
+ phy_port = tb_phy_port_from_link(TBNET_L0_PORT_NUM(xd->route));
+
+ /* Unicast and locally administered MAC */
+ dev->dev_addr[0] = phy_port << 4 | 0x02;
+ hash = jhash2((u32 *)xd->local_uuid, 4, 0);
+ memcpy(dev->dev_addr + 1, &hash, sizeof(hash));
+ hash = jhash2((u32 *)xd->local_uuid, 4, hash);
+ dev->dev_addr[5] = hash & 0xff;
+}
+
+static int tbnet_probe(struct tb_service *svc, const struct tb_service_id *id)
+{
+ struct tb_xdomain *xd = tb_service_parent(svc);
+ struct net_device *dev;
+ struct tbnet *net;
+ int ret;
+
+ dev = alloc_etherdev(sizeof(*net));
+ if (!dev)
+ return -ENOMEM;
+
+ SET_NETDEV_DEV(dev, &svc->dev);
+
+ net = netdev_priv(dev);
+ INIT_DELAYED_WORK(&net->login_work, tbnet_login_work);
+ INIT_WORK(&net->connected_work, tbnet_connected_work);
+ mutex_init(&net->connection_lock);
+ atomic_set(&net->command_id, 0);
+ atomic_set(&net->frame_id, 0);
+ net->svc = svc;
+ net->dev = dev;
+ net->xd = xd;
+
+ tbnet_generate_mac(dev);
+
+ strcpy(dev->name, "thunderbolt%d");
+ dev->netdev_ops = &tbnet_netdev_ops;
+
+ /* ThunderboltIP takes advantage of TSO packets but instead of
+ * segmenting them we just split the packet into Thunderbolt
+ * frames (maximum payload size of each frame is 4084 bytes) and
+ * calculate checksum over the whole packet here.
+ *
+ * The receiving side does the opposite if the host OS supports
+ * LRO, otherwise it needs to split the large packet into MTU
+ * sized smaller packets.
+ *
+ * In order to receive large packets from the networking stack,
+ * we need to announce support for most of the offloading
+ * features here.
+ */
+ dev->hw_features = NETIF_F_SG | NETIF_F_ALL_TSO | NETIF_F_GRO |
+ NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM;
+ dev->features = dev->hw_features | NETIF_F_HIGHDMA;
+ dev->hard_header_len += sizeof(struct thunderbolt_ip_frame_header);
+
+ netif_napi_add(dev, &net->napi, tbnet_poll, NAPI_POLL_WEIGHT);
+
+ /* MTU range: 68 - 65522 */
+ dev->min_mtu = ETH_MIN_MTU;
+ dev->max_mtu = TBNET_MAX_MTU - ETH_HLEN;
+
+ net->handler.uuid = &tbnet_svc_uuid;
+ net->handler.callback = tbnet_handle_packet,
+ net->handler.data = net;
+ tb_register_protocol_handler(&net->handler);
+
+ tb_service_set_drvdata(svc, net);
+
+ ret = register_netdev(dev);
+ if (ret) {
+ tb_unregister_protocol_handler(&net->handler);
+ free_netdev(dev);
+ return ret;
+ }
+
+ return 0;
+}
+
+static void tbnet_remove(struct tb_service *svc)
+{
+ struct tbnet *net = tb_service_get_drvdata(svc);
+
+ unregister_netdev(net->dev);
+ tb_unregister_protocol_handler(&net->handler);
+ free_netdev(net->dev);
+}
+
+static void tbnet_shutdown(struct tb_service *svc)
+{
+ tbnet_tear_down(tb_service_get_drvdata(svc), true);
+}
+
+static int __maybe_unused tbnet_suspend(struct device *dev)
+{
+ struct tb_service *svc = tb_to_service(dev);
+ struct tbnet *net = tb_service_get_drvdata(svc);
+
+ stop_login(net);
+ if (netif_running(net->dev)) {
+ netif_device_detach(net->dev);
+ tb_ring_stop(net->rx_ring.ring);
+ tb_ring_stop(net->tx_ring.ring);
+ tbnet_free_buffers(&net->rx_ring);
+ tbnet_free_buffers(&net->tx_ring);
+ }
+
+ return 0;
+}
+
+static int __maybe_unused tbnet_resume(struct device *dev)
+{
+ struct tb_service *svc = tb_to_service(dev);
+ struct tbnet *net = tb_service_get_drvdata(svc);
+
+ netif_carrier_off(net->dev);
+ if (netif_running(net->dev)) {
+ netif_device_attach(net->dev);
+ start_login(net);
+ }
+
+ return 0;
+}
+
+static const struct dev_pm_ops tbnet_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(tbnet_suspend, tbnet_resume)
+};
+
+static const struct tb_service_id tbnet_ids[] = {
+ { TB_SERVICE("network", 1) },
+ { },
+};
+MODULE_DEVICE_TABLE(tbsvc, tbnet_ids);
+
+static struct tb_service_driver tbnet_driver = {
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "thunderbolt-net",
+ .pm = &tbnet_pm_ops,
+ },
+ .probe = tbnet_probe,
+ .remove = tbnet_remove,
+ .shutdown = tbnet_shutdown,
+ .id_table = tbnet_ids,
+};
+
+static int __init tbnet_init(void)
+{
+ int ret;
+
+ tbnet_dir = tb_property_create_dir(&tbnet_dir_uuid);
+ if (!tbnet_dir)
+ return -ENOMEM;
+
+ tb_property_add_immediate(tbnet_dir, "prtcid", 1);
+ tb_property_add_immediate(tbnet_dir, "prtcvers", 1);
+ tb_property_add_immediate(tbnet_dir, "prtcrevs", 1);
+ tb_property_add_immediate(tbnet_dir, "prtcstns",
+ TBNET_MATCH_FRAGS_ID);
+
+ ret = tb_register_property_dir("network", tbnet_dir);
+ if (ret) {
+ tb_property_free_dir(tbnet_dir);
+ return ret;
+ }
+
+ return tb_register_service_driver(&tbnet_driver);
+}
+module_init(tbnet_init);
+
+static void __exit tbnet_exit(void)
+{
+ tb_unregister_service_driver(&tbnet_driver);
+ tb_unregister_property_dir("network", tbnet_dir);
+ tb_property_free_dir(tbnet_dir);
+}
+module_exit(tbnet_exit);
+
+MODULE_AUTHOR("Amir Levy <amir.jer.levy@intel.com>");
+MODULE_AUTHOR("Michael Jamet <michael.jamet@intel.com>");
+MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
+MODULE_DESCRIPTION("Thunderbolt network driver");
+MODULE_LICENSE("GPL v2");