diff options
Diffstat (limited to 'drivers/net/thunderbolt.c')
| -rw-r--r-- | drivers/net/thunderbolt.c | 1362 |
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..435854688a7a --- /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; + u32 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"); |