Re: [Patch v7 05/22] CIFS: SMBD: Establish SMB Direct connection
From: ronnie sahlberg
Date: Sun Nov 19 2017 - 20:36:55 EST
On Tue, Nov 7, 2017 at 6:54 PM, Long Li <longli@xxxxxxxxxxxxxxxxxxxxxx> wrote:
> From: Long Li <longli@xxxxxxxxxxxxx>
>
> Add code to implement the core functions to establish a SMB Direct connection.
>
> 1. Establish an RDMA connection to SMB server.
> 2. Negotiate and setup SMB Direct protocol.
> 3. Implement idle connection timer and credit management.
>
> SMB Direct is enabled by setting CONFIG_CIFS_SMB_DIRECT.
>
> Add to Makefile to enable building SMB Direct.
>
> Signed-off-by: Long Li <longli@xxxxxxxxxxxxx>
> ---
> fs/cifs/Makefile | 2 +
> fs/cifs/smbdirect.c | 1576 +++++++++++++++++++++++++++++++++++++++++++++++++++
> fs/cifs/smbdirect.h | 280 +++++++++
> 3 files changed, 1858 insertions(+)
>
> diff --git a/fs/cifs/Makefile b/fs/cifs/Makefile
> index 5e853a3..ad00873 100644
> --- a/fs/cifs/Makefile
> +++ b/fs/cifs/Makefile
> @@ -18,3 +18,5 @@ cifs-$(CONFIG_CIFS_UPCALL) += cifs_spnego.o
> cifs-$(CONFIG_CIFS_DFS_UPCALL) += dns_resolve.o cifs_dfs_ref.o
>
> cifs-$(CONFIG_CIFS_FSCACHE) += fscache.o cache.o
> +
> +cifs-$(CONFIG_CIFS_SMB_DIRECT) += smbdirect.o
> diff --git a/fs/cifs/smbdirect.c b/fs/cifs/smbdirect.c
> index d3c16f8..021d527 100644
> --- a/fs/cifs/smbdirect.c
> +++ b/fs/cifs/smbdirect.c
> @@ -13,7 +13,34 @@
> * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
> * the GNU General Public License for more details.
> */
> +#include <linux/module.h>
> #include "smbdirect.h"
> +#include "cifs_debug.h"
> +
> +static struct smbd_response *get_empty_queue_buffer(
> + struct smbd_connection *info);
> +static struct smbd_response *get_receive_buffer(
> + struct smbd_connection *info);
> +static void put_receive_buffer(
> + struct smbd_connection *info,
> + struct smbd_response *response,
> + bool lock);
> +static int allocate_receive_buffers(struct smbd_connection *info, int num_buf);
> +static void destroy_receive_buffers(struct smbd_connection *info);
> +
> +static void put_empty_packet(
> + struct smbd_connection *info, struct smbd_response *response);
> +static void enqueue_reassembly(
> + struct smbd_connection *info,
> + struct smbd_response *response, int data_length);
> +static struct smbd_response *_get_first_reassembly(
> + struct smbd_connection *info);
> +
> +static int smbd_post_recv(
> + struct smbd_connection *info,
> + struct smbd_response *response);
> +
> +static int smbd_post_send_empty(struct smbd_connection *info);
>
> /* SMBD version number */
> #define SMBD_V1 0x0100
> @@ -75,3 +102,1552 @@ int smbd_max_frmr_depth = 2048;
>
> /* If payload is less than this byte, use RDMA send/recv not read/write */
> int rdma_readwrite_threshold = 4096;
> +
> +/* Transport logging functions
> + * Logging are defined as classes. They can be OR'ed to define the actual
> + * logging level via module parameter smbd_logging_class
> + * e.g. cifs.smbd_logging_class=0x500 will log all log_rdma_recv() and
> + * log_rdma_event()
Should be 0xa0 ?
> + */
> +#define LOG_OUTGOING 0x1
> +#define LOG_INCOMING 0x2
> +#define LOG_READ 0x4
> +#define LOG_WRITE 0x8
> +#define LOG_RDMA_SEND 0x10
> +#define LOG_RDMA_RECV 0x20
> +#define LOG_KEEP_ALIVE 0x40
> +#define LOG_RDMA_EVENT 0x80
> +#define LOG_RDMA_MR 0x100
> +static unsigned int smbd_logging_class = 0;
> +module_param(smbd_logging_class, uint, 0644);
> +MODULE_PARM_DESC(smbd_logging_class,
> + "Logging class for SMBD transport 0x0 to 0x100");
> +
> +#define ERR 0x0
> +#define INFO 0x1
> +static unsigned int smbd_logging_level = ERR;
> +module_param(smbd_logging_level, uint, 0644);
> +MODULE_PARM_DESC(smbd_logging_level,
> + "Logging level for SMBD transport, 0 (default): error, 1: info");
> +
> +#define log_rdma(level, class, fmt, args...) \
> +do { \
> + if (level <= smbd_logging_level || class & smbd_logging_class) \
> + cifs_dbg(VFS, "%s:%d " fmt, __func__, __LINE__, ##args);\
> +} while (0)
> +
> +#define log_outgoing(level, fmt, args...) \
> + log_rdma(level, LOG_OUTGOING, fmt, ##args)
> +#define log_incoming(level, fmt, args...) \
> + log_rdma(level, LOG_INCOMING, fmt, ##args)
> +#define log_read(level, fmt, args...) log_rdma(level, LOG_READ, fmt, ##args)
> +#define log_write(level, fmt, args...) log_rdma(level, LOG_WRITE, fmt, ##args)
> +#define log_rdma_send(level, fmt, args...) \
> + log_rdma(level, LOG_RDMA_SEND, fmt, ##args)
> +#define log_rdma_recv(level, fmt, args...) \
> + log_rdma(level, LOG_RDMA_RECV, fmt, ##args)
> +#define log_keep_alive(level, fmt, args...) \
> + log_rdma(level, LOG_KEEP_ALIVE, fmt, ##args)
> +#define log_rdma_event(level, fmt, args...) \
> + log_rdma(level, LOG_RDMA_EVENT, fmt, ##args)
> +#define log_rdma_mr(level, fmt, args...) \
> + log_rdma(level, LOG_RDMA_MR, fmt, ##args)
> +
> +/*
> + * Destroy the transport and related RDMA and memory resources
> + * Need to go through all the pending counters and make sure on one is using
> + * the transport while it is destroyed
> + */
> +static void smbd_destroy_rdma_work(struct work_struct *work)
> +{
> + struct smbd_response *response;
> + struct smbd_connection *info =
> + container_of(work, struct smbd_connection, destroy_work);
> + unsigned long flags;
> +
> + log_rdma_event(INFO, "destroying qp\n");
> + ib_drain_qp(info->id->qp);
> + rdma_destroy_qp(info->id);
> +
> + /* Unblock all I/O waiting on the send queue */
> + wake_up_interruptible_all(&info->wait_send_queue);
> +
> + log_rdma_event(INFO, "cancelling idle timer\n");
> + cancel_delayed_work_sync(&info->idle_timer_work);
> + log_rdma_event(INFO, "cancelling send immediate work\n");
> + cancel_delayed_work_sync(&info->send_immediate_work);
> +
> + log_rdma_event(INFO, "wait for all recv to finish\n");
> + wake_up_interruptible(&info->wait_reassembly_queue);
> +
> + log_rdma_event(INFO, "wait for all send posted to IB to finish\n");
> + wait_event(info->wait_send_pending,
> + atomic_read(&info->send_pending) == 0);
> + wait_event(info->wait_send_payload_pending,
> + atomic_read(&info->send_payload_pending) == 0);
> +
> + /* It's not posssible for upper layer to get to reassembly */
> + log_rdma_event(INFO, "drain the reassembly queue\n");
> + do {
> + spin_lock_irqsave(&info->reassembly_queue_lock, flags);
> + response = _get_first_reassembly(info);
> + if (response) {
> + list_del(&response->list);
> + spin_unlock_irqrestore(
> + &info->reassembly_queue_lock, flags);
> + put_receive_buffer(info, response, true);
> + }
> + } while (response);
> + spin_unlock_irqrestore(&info->reassembly_queue_lock, flags);
> + info->reassembly_data_length = 0;
> +
> + log_rdma_event(INFO, "free receive buffers\n");
> + wait_event(info->wait_receive_queues,
> + info->count_receive_queue + info->count_empty_packet_queue
> + == info->receive_credit_max);
> + destroy_receive_buffers(info);
> +
> + ib_free_cq(info->send_cq);
> + ib_free_cq(info->recv_cq);
> + ib_dealloc_pd(info->pd);
> + rdma_destroy_id(info->id);
> +
> + /* free mempools */
> + mempool_destroy(info->request_mempool);
> + kmem_cache_destroy(info->request_cache);
> +
> + mempool_destroy(info->response_mempool);
> + kmem_cache_destroy(info->response_cache);
> +
> + info->transport_status = SMBD_DESTROYED;
> + wake_up_all(&info->wait_destroy);
> +}
> +
> +static int smbd_process_disconnected(struct smbd_connection *info)
> +{
> +// queue_work(info->workqueue, &info->destroy_work);
> + schedule_work(&info->destroy_work);
> + return 0;
> +}
> +
> +static void smbd_disconnect_rdma_work(struct work_struct *work)
> +{
> + struct smbd_connection *info =
> + container_of(work, struct smbd_connection, disconnect_work);
> +
> + if (info->transport_status == SMBD_CONNECTED) {
> + info->transport_status = SMBD_DISCONNECTING;
> + rdma_disconnect(info->id);
> + }
> +}
> +
> +static void smbd_disconnect_rdma_connection(struct smbd_connection *info)
> +{
> + queue_work(info->workqueue, &info->disconnect_work);
> +}
> +
> +/* Upcall from RDMA CM */
> +static int smbd_conn_upcall(
> + struct rdma_cm_id *id, struct rdma_cm_event *event)
> +{
> + struct smbd_connection *info = id->context;
> +
> + log_rdma_event(INFO, "event=%d status=%d\n",
> + event->event, event->status);
> +
> + switch (event->event) {
> + case RDMA_CM_EVENT_ADDR_RESOLVED:
> + case RDMA_CM_EVENT_ROUTE_RESOLVED:
> + info->ri_rc = 0;
> + complete(&info->ri_done);
> + break;
> +
> + case RDMA_CM_EVENT_ADDR_ERROR:
> + info->ri_rc = -EHOSTUNREACH;
> + complete(&info->ri_done);
> + break;
> +
> + case RDMA_CM_EVENT_ROUTE_ERROR:
> + info->ri_rc = -ENETUNREACH;
> + complete(&info->ri_done);
> + break;
> +
> + case RDMA_CM_EVENT_ESTABLISHED:
> + log_rdma_event(INFO, "connected event=%d\n", event->event);
> + info->transport_status = SMBD_CONNECTED;
> + wake_up_interruptible(&info->conn_wait);
> + break;
> +
> + case RDMA_CM_EVENT_CONNECT_ERROR:
> + case RDMA_CM_EVENT_UNREACHABLE:
> + case RDMA_CM_EVENT_REJECTED:
> + log_rdma_event(INFO, "connecting failed event=%d\n", event->event);
> + info->transport_status = SMBD_DISCONNECTED;
> + wake_up_interruptible(&info->conn_wait);
> + break;
> +
> + case RDMA_CM_EVENT_DEVICE_REMOVAL:
> + case RDMA_CM_EVENT_DISCONNECTED:
> + /* This happenes when we fail the negotiation */
> + if (info->transport_status == SMBD_NEGOTIATE_FAILED) {
> + info->transport_status = SMBD_DISCONNECTED;
> + wake_up(&info->conn_wait);
> + break;
> + }
> +
> + info->transport_status = SMBD_DISCONNECTED;
> + smbd_process_disconnected(info);
> + break;
> +
> + default:
> + break;
> + }
> +
> + return 0;
> +}
> +
> +/* Upcall from RDMA QP */
> +static void
> +smbd_qp_async_error_upcall(struct ib_event *event, void *context)
> +{
> + struct smbd_connection *info = context;
> +
> + log_rdma_event(ERR, "%s on device %s info %p\n",
> + ib_event_msg(event->event), event->device->name, info);
> +
> + switch (event->event) {
> + case IB_EVENT_CQ_ERR:
> + case IB_EVENT_QP_FATAL:
> + smbd_disconnect_rdma_connection(info);
> +
> + default:
> + break;
> + }
> +}
> +
> +static inline void *smbd_request_payload(struct smbd_request *request)
> +{
> + return (void *)request->packet;
> +}
> +
> +static inline void *smbd_response_payload(struct smbd_response *response)
> +{
> + return (void *)response->packet;
> +}
> +
> +/* Called when a RDMA send is done */
> +static void send_done(struct ib_cq *cq, struct ib_wc *wc)
> +{
> + int i;
> + struct smbd_request *request =
> + container_of(wc->wr_cqe, struct smbd_request, cqe);
> +
> + log_rdma_send(INFO, "smbd_request %p completed wc->status=%d\n",
> + request, wc->status);
> +
> + if (wc->status != IB_WC_SUCCESS || wc->opcode != IB_WC_SEND) {
> + log_rdma_send(ERR, "wc->status=%d wc->opcode=%d\n",
> + wc->status, wc->opcode);
> + smbd_disconnect_rdma_connection(request->info);
> + }
> +
> + for (i = 0; i < request->num_sge; i++)
> + ib_dma_unmap_single(request->info->id->device,
> + request->sge[i].addr,
> + request->sge[i].length,
> + DMA_TO_DEVICE);
> +
> + if (request->has_payload) {
> + if (atomic_dec_and_test(&request->info->send_payload_pending))
> + wake_up(&request->info->wait_send_payload_pending);
> + } else {
> + if (atomic_dec_and_test(&request->info->send_pending))
> + wake_up(&request->info->wait_send_pending);
> + }
> +
> + mempool_free(request, request->info->request_mempool);
> +}
> +
> +static void dump_smbd_negotiate_resp(struct smbd_negotiate_resp *resp)
> +{
> + log_rdma_event(INFO, "resp message min_version %u max_version %u "
> + "negotiated_version %u credits_requested %u "
> + "credits_granted %u status %u max_readwrite_size %u "
> + "preferred_send_size %u max_receive_size %u "
> + "max_fragmented_size %u\n",
> + resp->min_version, resp->max_version, resp->negotiated_version,
> + resp->credits_requested, resp->credits_granted, resp->status,
> + resp->max_readwrite_size, resp->preferred_send_size,
> + resp->max_receive_size, resp->max_fragmented_size);
> +}
> +
> +/*
> + * Process a negotiation response message, according to [MS-SMBD]3.1.5.7
> + * response, packet_length: the negotiation response message
> + * return value: true if negotiation is a success, false if failed
> + */
> +static bool process_negotiation_response(
> + struct smbd_response *response, int packet_length)
> +{
> + struct smbd_connection *info = response->info;
> + struct smbd_negotiate_resp *packet = smbd_response_payload(response);
> +
> + if (packet_length < sizeof(struct smbd_negotiate_resp)) {
> + log_rdma_event(ERR,
> + "error: packet_length=%d\n", packet_length);
> + return false;
> + }
> +
> + if (le16_to_cpu(packet->negotiated_version) != SMBD_V1) {
> + log_rdma_event(ERR, "error: negotiated_version=%x\n",
> + le16_to_cpu(packet->negotiated_version));
> + return false;
> + }
> + info->protocol = le16_to_cpu(packet->negotiated_version);
> +
> + if (packet->credits_requested == 0) {
> + log_rdma_event(ERR, "error: credits_requested==0\n");
> + return false;
> + }
> + info->receive_credit_target = le16_to_cpu(packet->credits_requested);
> +
> + if (packet->credits_granted == 0) {
> + log_rdma_event(ERR, "error: credits_granted==0\n");
> + return false;
> + }
> + atomic_set(&info->send_credits, le16_to_cpu(packet->credits_granted));
> +
> + atomic_set(&info->receive_credits, 0);
> +
> + if (le32_to_cpu(packet->preferred_send_size) > info->max_receive_size) {
> + log_rdma_event(ERR, "error: preferred_send_size=%d\n",
> + le32_to_cpu(packet->preferred_send_size));
> + return false;
> + }
> + info->max_receive_size = le32_to_cpu(packet->preferred_send_size);
> +
> + if (le32_to_cpu(packet->max_receive_size) < SMBD_MIN_RECEIVE_SIZE) {
> + log_rdma_event(ERR, "error: max_receive_size=%d\n",
> + le32_to_cpu(packet->max_receive_size));
> + return false;
> + }
> + info->max_send_size = min_t(int, info->max_send_size,
> + le32_to_cpu(packet->max_receive_size));
> +
> + if (le32_to_cpu(packet->max_fragmented_size) <
> + SMBD_MIN_FRAGMENTED_SIZE) {
> + log_rdma_event(ERR, "error: max_fragmented_size=%d\n",
> + le32_to_cpu(packet->max_fragmented_size));
> + return false;
> + }
> + info->max_fragmented_send_size =
> + le32_to_cpu(packet->max_fragmented_size);
> +
> + return true;
> +}
> +
> +/*
> + * Check and schedule to send an immediate packet
> + * This is used to extend credtis to remote peer to keep the transport busy
> + */
> +static void check_and_send_immediate(struct smbd_connection *info)
> +{
> + if (info->transport_status != SMBD_CONNECTED)
> + return;
> +
> + info->send_immediate = true;
> +
> + /*
> + * Promptly send a packet if our peer is running low on receive
> + * credits
> + */
> + if (atomic_read(&info->receive_credits) <
> + info->receive_credit_target - 1)
> + queue_delayed_work(
> + info->workqueue, &info->send_immediate_work, 0);
> +}
> +
> +static void smbd_post_send_credits(struct work_struct *work)
> +{
> + int ret = 0;
> + int use_receive_queue = 1;
> + int rc;
> + struct smbd_response *response;
> + struct smbd_connection *info =
> + container_of(work, struct smbd_connection,
> + post_send_credits_work);
> +
> + if (info->transport_status != SMBD_CONNECTED) {
> + wake_up(&info->wait_receive_queues);
> + return;
> + }
> +
> + if (info->receive_credit_target >
> + atomic_read(&info->receive_credits)) {
> + while (true) {
> + if (use_receive_queue)
> + response = get_receive_buffer(info);
> + else
> + response = get_empty_queue_buffer(info);
> + if (!response) {
> + /* now switch to emtpy packet queue */
> + if (use_receive_queue) {
> + use_receive_queue = 0;
> + continue;
> + } else
> + break;
> + }
> +
> + response->type = SMBD_TRANSFER_DATA;
> + response->first_segment = false;
> + rc = smbd_post_recv(info, response);
> + if (rc) {
> + log_rdma_recv(ERR,
> + "post_recv failed rc=%d\n", rc);
> + put_receive_buffer(info, response, true);
> + break;
> + }
> +
> + ret++;
> + }
> + }
> +
> + spin_lock(&info->lock_new_credits_offered);
> + info->new_credits_offered += ret;
> + spin_unlock(&info->lock_new_credits_offered);
> +
> + atomic_add(ret, &info->receive_credits);
> +
> + /* Check if we can post new receive and grant credits to peer */
> + check_and_send_immediate(info);
> +}
> +
> +static void smbd_recv_done_work(struct work_struct *work)
> +{
> + struct smbd_connection *info =
> + container_of(work, struct smbd_connection, recv_done_work);
> +
> + /*
> + * We may have new send credits granted from remote peer
> + * If any sender is blcoked on lack of credets, unblock it
> + */
> + if (atomic_read(&info->send_credits))
> + wake_up_interruptible(&info->wait_send_queue);
> +
> + /*
> + * Check if we need to send something to remote peer to
> + * grant more credits or respond to KEEP_ALIVE packet
> + */
> + check_and_send_immediate(info);
> +}
> +
> +/* Called from softirq, when recv is done */
> +static void recv_done(struct ib_cq *cq, struct ib_wc *wc)
> +{
> + struct smbd_data_transfer *data_transfer;
> + struct smbd_response *response =
> + container_of(wc->wr_cqe, struct smbd_response, cqe);
> + struct smbd_connection *info = response->info;
> + int data_length = 0;
> +
> + log_rdma_recv(INFO, "response=%p type=%d wc status=%d wc opcode %d "
> + "byte_len=%d pkey_index=%x\n",
> + response, response->type, wc->status, wc->opcode,
> + wc->byte_len, wc->pkey_index);
> +
> + if (wc->status != IB_WC_SUCCESS || wc->opcode != IB_WC_RECV) {
> + log_rdma_recv(INFO, "wc->status=%d opcode=%d\n",
> + wc->status, wc->opcode);
> + smbd_disconnect_rdma_connection(info);
> + goto error;
> + }
> +
> + ib_dma_sync_single_for_cpu(
> + wc->qp->device,
> + response->sge.addr,
> + response->sge.length,
> + DMA_FROM_DEVICE);
> +
> + switch (response->type) {
> + /* SMBD negotiation response */
> + case SMBD_NEGOTIATE_RESP:
> + dump_smbd_negotiate_resp(smbd_response_payload(response));
> + info->full_packet_received = true;
> + info->negotiate_done =
> + process_negotiation_response(response, wc->byte_len);
> + complete(&info->negotiate_completion);
> + break;
> +
> + /* SMBD data transfer packet */
> + case SMBD_TRANSFER_DATA:
> + data_transfer = smbd_response_payload(response);
> + data_length = le32_to_cpu(data_transfer->data_length);
> +
> + /*
> + * If this is a packet with data playload place the data in
> + * reassembly queue and wake up the reading thread
> + */
> + if (data_length) {
> + if (info->full_packet_received)
> + response->first_segment = true;
> +
> + if (le32_to_cpu(data_transfer->remaining_data_length))
> + info->full_packet_received = false;
> + else
> + info->full_packet_received = true;
> +
> + enqueue_reassembly(
> + info,
> + response,
> + data_length);
> + } else
> + put_empty_packet(info, response);
> +
> + if (data_length)
> + wake_up_interruptible(&info->wait_reassembly_queue);
> +
> + atomic_dec(&info->receive_credits);
> + info->receive_credit_target =
> + le16_to_cpu(data_transfer->credits_requested);
> + atomic_add(le16_to_cpu(data_transfer->credits_granted),
> + &info->send_credits);
> +
> + log_incoming(INFO, "data flags %d data_offset %d "
> + "data_length %d remaining_data_length %d\n",
> + le16_to_cpu(data_transfer->flags),
> + le32_to_cpu(data_transfer->data_offset),
> + le32_to_cpu(data_transfer->data_length),
> + le32_to_cpu(data_transfer->remaining_data_length));
> +
> + /* Send a KEEP_ALIVE response right away if requested */
> + info->keep_alive_requested = KEEP_ALIVE_NONE;
> + if (le16_to_cpu(data_transfer->flags) &
> + SMB_DIRECT_RESPONSE_REQUESTED) {
> + info->keep_alive_requested = KEEP_ALIVE_PENDING;
> + }
> +
> + queue_work(info->workqueue, &info->recv_done_work);
> + return;
> +
> + default:
> + log_rdma_recv(ERR,
> + "unexpected response type=%d\n", response->type);
> + }
> +
> +error:
> + put_receive_buffer(info, response, true);
> +}
> +
> +static struct rdma_cm_id *smbd_create_id(
> + struct smbd_connection *info,
> + struct sockaddr *dstaddr, int port)
> +{
> + struct rdma_cm_id *id;
> + int rc;
> + __be16 *sport;
> +
> + id = rdma_create_id(&init_net, smbd_conn_upcall, info,
> + RDMA_PS_TCP, IB_QPT_RC);
> + if (IS_ERR(id)) {
> + rc = PTR_ERR(id);
> + log_rdma_event(ERR, "rdma_create_id() failed %i\n", rc);
> + return id;
> + }
> +
> + if (dstaddr->sa_family == AF_INET6)
> + sport = &((struct sockaddr_in6 *)dstaddr)->sin6_port;
> + else
> + sport = &((struct sockaddr_in *)dstaddr)->sin_port;
> +
> + *sport = htons(port);
> +
> + init_completion(&info->ri_done);
> + info->ri_rc = -ETIMEDOUT;
> +
> + rc = rdma_resolve_addr(id, NULL, (struct sockaddr *)dstaddr,
> + RDMA_RESOLVE_TIMEOUT);
> + if (rc) {
> + log_rdma_event(ERR, "rdma_resolve_addr() failed %i\n", rc);
> + goto out;
> + }
> + wait_for_completion_interruptible_timeout(
> + &info->ri_done, msecs_to_jiffies(RDMA_RESOLVE_TIMEOUT));
> + rc = info->ri_rc;
> + if (rc) {
> + log_rdma_event(ERR, "rdma_resolve_addr() completed %i\n", rc);
> + goto out;
> + }
> +
> + info->ri_rc = -ETIMEDOUT;
> + rc = rdma_resolve_route(id, RDMA_RESOLVE_TIMEOUT);
> + if (rc) {
> + log_rdma_event(ERR, "rdma_resolve_route() failed %i\n", rc);
> + goto out;
> + }
> + wait_for_completion_interruptible_timeout(
> + &info->ri_done, msecs_to_jiffies(RDMA_RESOLVE_TIMEOUT));
> + rc = info->ri_rc;
> + if (rc) {
> + log_rdma_event(ERR, "rdma_resolve_route() completed %i\n", rc);
> + goto out;
> + }
> +
> + return id;
> +
> +out:
> + rdma_destroy_id(id);
> + return ERR_PTR(rc);
> +}
> +
> +/*
> + * Test if FRWR (Fast Registration Work Requests) is supported on the device
> + * This implementation requries FRWR on RDMA read/write
> + * return value: true if it is supported
> + */
> +static bool frwr_is_supported(struct ib_device_attr *attrs)
> +{
> + if (!(attrs->device_cap_flags & IB_DEVICE_MEM_MGT_EXTENSIONS))
> + return false;
> + if (attrs->max_fast_reg_page_list_len == 0)
> + return false;
> + return true;
> +}
> +
> +static int smbd_ia_open(
> + struct smbd_connection *info,
> + struct sockaddr *dstaddr, int port)
> +{
> + int rc;
> +
> + info->id = smbd_create_id(info, dstaddr, port);
> + if (IS_ERR(info->id)) {
> + rc = PTR_ERR(info->id);
> + goto out1;
> + }
> +
> + if (!frwr_is_supported(&info->id->device->attrs)) {
> + log_rdma_event(ERR,
> + "Fast Registration Work Requests "
> + "(FRWR) is not supported\n");
> + log_rdma_event(ERR,
> + "Device capability flags = %llx "
> + "max_fast_reg_page_list_len = %u\n",
> + info->id->device->attrs.device_cap_flags,
> + info->id->device->attrs.max_fast_reg_page_list_len);
> + rc = -EPROTONOSUPPORT;
> + goto out2;
> + }
> +
> + info->pd = ib_alloc_pd(info->id->device, 0);
> + if (IS_ERR(info->pd)) {
> + rc = PTR_ERR(info->pd);
> + log_rdma_event(ERR, "ib_alloc_pd() returned %d\n", rc);
> + goto out2;
> + }
> +
> + return 0;
> +
> +out2:
> + rdma_destroy_id(info->id);
> + info->id = NULL;
> +
> +out1:
> + return rc;
> +}
> +
> +/*
> + * Send a negotiation request message to the peer
> + * The negotiation procedure is in [MS-SMBD] 3.1.5.2 and 3.1.5.3
> + * After negotiation, the transport is connected and ready for
> + * carrying upper layer SMB payload
> + */
> +static int smbd_post_send_negotiate_req(struct smbd_connection *info)
> +{
> + struct ib_send_wr send_wr, *send_wr_fail;
> + int rc = -ENOMEM;
> + struct smbd_request *request;
> + struct smbd_negotiate_req *packet;
> +
> + request = mempool_alloc(info->request_mempool, GFP_KERNEL);
> + if (!request)
> + return rc;
> +
> + request->info = info;
> +
> + packet = smbd_request_payload(request);
> + packet->min_version = cpu_to_le16(SMBD_V1);
> + packet->max_version = cpu_to_le16(SMBD_V1);
> + packet->reserved = 0;
> + packet->credits_requested = cpu_to_le16(info->send_credit_target);
> + packet->preferred_send_size = cpu_to_le32(info->max_send_size);
> + packet->max_receive_size = cpu_to_le32(info->max_receive_size);
> + packet->max_fragmented_size =
> + cpu_to_le32(info->max_fragmented_recv_size);
> +
> + request->num_sge = 1;
> + request->sge[0].addr = ib_dma_map_single(
> + info->id->device, (void *)packet,
> + sizeof(*packet), DMA_TO_DEVICE);
> + if (ib_dma_mapping_error(info->id->device, request->sge[0].addr)) {
> + rc = -EIO;
> + goto dma_mapping_failed;
> + }
> +
> + request->sge[0].length = sizeof(*packet);
> + request->sge[0].lkey = info->pd->local_dma_lkey;
> +
> + ib_dma_sync_single_for_device(
> + info->id->device, request->sge[0].addr,
> + request->sge[0].length, DMA_TO_DEVICE);
> +
> + request->cqe.done = send_done;
> +
> + send_wr.next = NULL;
> + send_wr.wr_cqe = &request->cqe;
> + send_wr.sg_list = request->sge;
> + send_wr.num_sge = request->num_sge;
> + send_wr.opcode = IB_WR_SEND;
> + send_wr.send_flags = IB_SEND_SIGNALED;
> +
> + log_rdma_send(INFO, "sge addr=%llx length=%x lkey=%x\n",
> + request->sge[0].addr,
> + request->sge[0].length, request->sge[0].lkey);
> +
> + request->has_payload = false;
> + atomic_inc(&info->send_pending);
> + rc = ib_post_send(info->id->qp, &send_wr, &send_wr_fail);
> + if (!rc)
> + return 0;
> +
> + /* if we reach here, post send failed */
> + log_rdma_send(ERR, "ib_post_send failed rc=%d\n", rc);
> + atomic_dec(&info->send_pending);
> + ib_dma_unmap_single(info->id->device, request->sge[0].addr,
> + request->sge[0].length, DMA_TO_DEVICE);
> +
> +dma_mapping_failed:
> + mempool_free(request, info->request_mempool);
> + return rc;
> +}
> +
> +/*
> + * Extend the credits to remote peer
> + * This implements [MS-SMBD] 3.1.5.9
> + * The idea is that we should extend credits to remote peer as quickly as
> + * it's allowed, to maintain data flow. We allocate as much receive
> + * buffer as possible, and extend the receive credits to remote peer
> + * return value: the new credtis being granted.
> + */
> +static int manage_credits_prior_sending(struct smbd_connection *info)
> +{
> + int new_credits;
> +
> + spin_lock(&info->lock_new_credits_offered);
> + new_credits = info->new_credits_offered;
> + info->new_credits_offered = 0;
> + spin_unlock(&info->lock_new_credits_offered);
> +
> + return new_credits;
> +}
> +
> +/*
> + * Check if we need to send a KEEP_ALIVE message
> + * The idle connection timer triggers a KEEP_ALIVE message when expires
> + * SMB_DIRECT_RESPONSE_REQUESTED is set in the message flag to have peer send
> + * back a response.
> + * return value:
> + * 1 if SMB_DIRECT_RESPONSE_REQUESTED needs to be set
> + * 0: otherwise
> + */
> +static int manage_keep_alive_before_sending(struct smbd_connection *info)
> +{
> + if (info->keep_alive_requested == KEEP_ALIVE_PENDING) {
> + info->keep_alive_requested = KEEP_ALIVE_SENT;
> + return 1;
> + }
> + return 0;
> +}
> +
> +/*
> + * Build and prepare the SMBD packet header
> + * This function waits for avaialbe send credits and build a SMBD packet
> + * header. The caller then optional append payload to the packet after
> + * the header
> + * intput values
> + * size: the size of the payload
> + * remaining_data_length: remaining data to send if this is part of a
> + * fragmented packet
> + * output values
> + * request_out: the request allocated from this function
> + * return values: 0 on success, otherwise actual error code returned
> + */
> +static int smbd_create_header(struct smbd_connection *info,
> + int size, int remaining_data_length,
> + struct smbd_request **request_out)
> +{
> + struct smbd_request *request;
> + struct smbd_data_transfer *packet;
> + int header_length;
> + int rc;
> +
> + /* Wait for send credits. A SMBD packet needs one credit */
> + rc = wait_event_interruptible(info->wait_send_queue,
> + atomic_read(&info->send_credits) > 0 ||
> + info->transport_status != SMBD_CONNECTED);
> + if (rc)
> + return rc;
> +
> + if (info->transport_status != SMBD_CONNECTED) {
> + log_outgoing(ERR, "disconnected not sending\n");
> + return -ENOENT;
> + }
> + atomic_dec(&info->send_credits);
> +
> + request = mempool_alloc(info->request_mempool, GFP_KERNEL);
> + if (!request) {
> + rc = -ENOMEM;
> + goto err;
> + }
> +
> + request->info = info;
> +
> + /* Fill in the packet header */
> + packet = smbd_request_payload(request);
> + packet->credits_requested = cpu_to_le16(info->send_credit_target);
> + packet->credits_granted =
> + cpu_to_le16(manage_credits_prior_sending(info));
> + info->send_immediate = false;
> +
> + packet->flags = 0;
> + if (manage_keep_alive_before_sending(info))
> + packet->flags |= cpu_to_le16(SMB_DIRECT_RESPONSE_REQUESTED);
> +
> + packet->reserved = 0;
> + if (!size)
> + packet->data_offset = 0;
> + else
> + packet->data_offset = cpu_to_le32(24);
> + packet->data_length = cpu_to_le32(size);
> + packet->remaining_data_length = cpu_to_le32(remaining_data_length);
> + packet->padding = 0;
> +
> + log_outgoing(INFO, "credits_requested=%d credits_granted=%d "
> + "data_offset=%d data_length=%d remaining_data_length=%d\n",
> + le16_to_cpu(packet->credits_requested),
> + le16_to_cpu(packet->credits_granted),
> + le32_to_cpu(packet->data_offset),
> + le32_to_cpu(packet->data_length),
> + le32_to_cpu(packet->remaining_data_length));
> +
> + /* Map the packet to DMA */
> + header_length = sizeof(struct smbd_data_transfer);
> + /* If this is a packet without payload, don't send padding */
> + if (!size)
> + header_length = offsetof(struct smbd_data_transfer, padding);
> +
> + request->num_sge = 1;
> + request->sge[0].addr = ib_dma_map_single(info->id->device,
> + (void *)packet,
> + header_length,
> + DMA_BIDIRECTIONAL);
> + if (ib_dma_mapping_error(info->id->device, request->sge[0].addr)) {
> + mempool_free(request, info->request_mempool);
> + rc = -EIO;
> + goto err;
> + }
> +
> + request->sge[0].length = header_length;
> + request->sge[0].lkey = info->pd->local_dma_lkey;
> +
> + *request_out = request;
> + return 0;
> +
> +err:
> + atomic_inc(&info->send_credits);
> + return rc;
> +}
> +
> +static void smbd_destroy_header(struct smbd_connection *info,
> + struct smbd_request *request)
> +{
> +
> + ib_dma_unmap_single(info->id->device,
> + request->sge[0].addr,
> + request->sge[0].length,
> + DMA_TO_DEVICE);
> + mempool_free(request, info->request_mempool);
> + atomic_inc(&info->send_credits);
> +}
> +
> +/* Post the send request */
> +static int smbd_post_send(struct smbd_connection *info,
> + struct smbd_request *request, bool has_payload)
> +{
> + struct ib_send_wr send_wr, *send_wr_fail;
> + int rc, i;
> +
> + for (i = 0; i < request->num_sge; i++) {
> + log_rdma_send(INFO,
> + "rdma_request sge[%d] addr=%llu legnth=%u\n",
> + i, request->sge[0].addr, request->sge[0].length);
> + ib_dma_sync_single_for_device(
> + info->id->device,
> + request->sge[i].addr,
> + request->sge[i].length,
> + DMA_TO_DEVICE);
> + }
> +
> + request->cqe.done = send_done;
> +
> + send_wr.next = NULL;
> + send_wr.wr_cqe = &request->cqe;
> + send_wr.sg_list = request->sge;
> + send_wr.num_sge = request->num_sge;
> + send_wr.opcode = IB_WR_SEND;
> + send_wr.send_flags = IB_SEND_SIGNALED;
> +
> + if (has_payload) {
> + request->has_payload = true;
> + atomic_inc(&info->send_payload_pending);
> + } else {
> + request->has_payload = false;
> + atomic_inc(&info->send_pending);
> + }
> +
> + rc = ib_post_send(info->id->qp, &send_wr, &send_wr_fail);
> + if (rc) {
> + log_rdma_send(ERR, "ib_post_send failed rc=%d\n", rc);
> + if (has_payload) {
> + if (atomic_dec_and_test(&info->send_payload_pending))
> + wake_up(&info->wait_send_payload_pending);
> + } else {
> + if (atomic_dec_and_test(&info->send_pending))
> + wake_up(&info->wait_send_pending);
> + }
> + } else
> + /* Reset timer for idle connection after packet is sent */
> + mod_delayed_work(info->workqueue, &info->idle_timer_work,
> + info->keep_alive_interval*HZ);
> +
> + return rc;
> +}
> +
> +static int smbd_post_send_sgl(struct smbd_connection *info,
> + struct scatterlist *sgl, int data_length, int remaining_data_length)
> +{
> + int num_sgs;
> + int i, rc;
> + struct smbd_request *request;
> + struct scatterlist *sg;
> +
> + rc = smbd_create_header(
> + info, data_length, remaining_data_length, &request);
> + if (rc)
> + return rc;
> +
> + num_sgs = sgl ? sg_nents(sgl) : 0;
> + for_each_sg(sgl, sg, num_sgs, i) {
> + request->sge[i+1].addr =
> + ib_dma_map_page(info->id->device, sg_page(sg),
> + sg->offset, sg->length, DMA_BIDIRECTIONAL);
> + if (ib_dma_mapping_error(
> + info->id->device, request->sge[i+1].addr)) {
> + rc = -EIO;
> + request->sge[i+1].addr = 0;
> + goto dma_mapping_failure;
> + }
> + request->sge[i+1].length = sg->length;
> + request->sge[i+1].lkey = info->pd->local_dma_lkey;
> + request->num_sge++;
> + }
> +
> + rc = smbd_post_send(info, request, data_length);
> + if (!rc)
> + return 0;
> +
> +dma_mapping_failure:
> + for (i = 1; i < request->num_sge; i++)
> + if (request->sge[i].addr)
> + ib_dma_unmap_single(info->id->device,
> + request->sge[i].addr,
> + request->sge[i].length,
> + DMA_TO_DEVICE);
> + smbd_destroy_header(info, request);
> + return rc;
> +}
> +
> +/*
> + * Send an empty message
> + * Empty message is used to extend credits to peer to for keep live
> + * while there is no upper layer payload to send at the time
> + */
> +static int smbd_post_send_empty(struct smbd_connection *info)
> +{
> + info->count_send_empty++;
> + return smbd_post_send_sgl(info, NULL, 0, 0);
> +}
> +
> +/*
> + * Post a receive request to the transport
> + * The remote peer can only send data when a receive request is posted
> + * The interaction is controlled by send/receive credit system
> + */
> +static int smbd_post_recv(
> + struct smbd_connection *info, struct smbd_response *response)
> +{
> + struct ib_recv_wr recv_wr, *recv_wr_fail = NULL;
> + int rc = -EIO;
> +
> + response->sge.addr = ib_dma_map_single(
> + info->id->device, response->packet,
> + info->max_receive_size, DMA_FROM_DEVICE);
> + if (ib_dma_mapping_error(info->id->device, response->sge.addr))
> + return rc;
> +
> + response->sge.length = info->max_receive_size;
> + response->sge.lkey = info->pd->local_dma_lkey;
> +
> + response->cqe.done = recv_done;
> +
> + recv_wr.wr_cqe = &response->cqe;
> + recv_wr.next = NULL;
> + recv_wr.sg_list = &response->sge;
> + recv_wr.num_sge = 1;
> +
> + rc = ib_post_recv(info->id->qp, &recv_wr, &recv_wr_fail);
> + if (rc) {
> + ib_dma_unmap_single(info->id->device, response->sge.addr,
> + response->sge.length, DMA_FROM_DEVICE);
> +
> + log_rdma_recv(ERR, "ib_post_recv failed rc=%d\n", rc);
> + }
> +
> + return rc;
> +}
> +
> +/* Perform SMBD negotiate according to [MS-SMBD] 3.1.5.2 */
> +static int smbd_negotiate(struct smbd_connection *info)
> +{
> + int rc;
> + struct smbd_response *response = get_receive_buffer(info);
> +
> + response->type = SMBD_NEGOTIATE_RESP;
> + rc = smbd_post_recv(info, response);
> + log_rdma_event(INFO,
> + "smbd_post_recv rc=%d iov.addr=%llx iov.length=%x "
> + "iov.lkey=%x\n",
> + rc, response->sge.addr,
> + response->sge.length, response->sge.lkey);
> + if (rc)
> + return rc;
> +
> + init_completion(&info->negotiate_completion);
> + info->negotiate_done = false;
> + rc = smbd_post_send_negotiate_req(info);
> + if (rc)
> + return rc;
> +
> + rc = wait_for_completion_interruptible_timeout(
> + &info->negotiate_completion, SMBD_NEGOTIATE_TIMEOUT * HZ);
> + log_rdma_event(INFO, "wait_for_completion_timeout rc=%d\n", rc);
> +
> + if (info->negotiate_done)
> + return 0;
> +
> + if (rc == 0)
> + rc = -ETIMEDOUT;
> + else if (rc == -ERESTARTSYS)
> + rc = -EINTR;
> + else
> + rc = -ENOTCONN;
> +
> + return rc;
> +}
> +
> +static void put_empty_packet(
> + struct smbd_connection *info, struct smbd_response *response)
> +{
> + spin_lock(&info->empty_packet_queue_lock);
> + list_add_tail(&response->list, &info->empty_packet_queue);
> + info->count_empty_packet_queue++;
> + spin_unlock(&info->empty_packet_queue_lock);
> +
> + queue_work(info->workqueue, &info->post_send_credits_work);
> +}
> +
> +/*
> + * Implement Connection.FragmentReassemblyBuffer defined in [MS-SMBD] 3.1.1.1
> + * This is a queue for reassembling upper layer payload and present to upper
> + * layer. All the inncoming payload go to the reassembly queue, regardless of
> + * if reassembly is required. The uuper layer code reads from the queue for all
> + * incoming payloads.
> + * Put a received packet to the reassembly queue
> + * response: the packet received
> + * data_length: the size of payload in this packet
> + */
> +static void enqueue_reassembly(
> + struct smbd_connection *info,
> + struct smbd_response *response,
> + int data_length)
> +{
> + spin_lock(&info->reassembly_queue_lock);
> + list_add_tail(&response->list, &info->reassembly_queue);
> + info->reassembly_queue_length++;
> + /*
> + * Make sure reassembly_data_length is updated after list and
> + * reassembly_queue_length are updated. On the dequeue side
> + * reassembly_data_length is checked without a lock to determine
> + * if reassembly_queue_length and list is up to date
> + */
> + virt_wmb();
> + info->reassembly_data_length += data_length;
> + spin_unlock(&info->reassembly_queue_lock);
> + info->count_reassembly_queue++;
> + info->count_enqueue_reassembly_queue++;
> +}
> +
> +/*
> + * Get the first entry at the front of reassembly queue
> + * Caller is responsible for locking
> + * return value: the first entry if any, NULL if queue is empty
> + */
> +static struct smbd_response *_get_first_reassembly(struct smbd_connection *info)
> +{
> + struct smbd_response *ret = NULL;
> +
> + if (!list_empty(&info->reassembly_queue)) {
> + ret = list_first_entry(
> + &info->reassembly_queue,
> + struct smbd_response, list);
> + }
> + return ret;
> +}
> +
> +static struct smbd_response *get_empty_queue_buffer(
> + struct smbd_connection *info)
> +{
> + struct smbd_response *ret = NULL;
> + unsigned long flags;
> +
> + spin_lock_irqsave(&info->empty_packet_queue_lock, flags);
> + if (!list_empty(&info->empty_packet_queue)) {
> + ret = list_first_entry(
> + &info->empty_packet_queue,
> + struct smbd_response, list);
> + list_del(&ret->list);
> + info->count_empty_packet_queue--;
> + }
> + spin_unlock_irqrestore(&info->empty_packet_queue_lock, flags);
> +
> + return ret;
> +}
> +
> +/*
> + * Get a receive buffer
> + * For each remote send, we need to post a receive. The receive buffers are
> + * pre-allocated in advance.
> + * return value: the receive buffer, NULL if none is available
> + */
> +static struct smbd_response *get_receive_buffer(struct smbd_connection *info)
> +{
> + struct smbd_response *ret = NULL;
> + unsigned long flags;
> +
> + spin_lock_irqsave(&info->receive_queue_lock, flags);
> + if (!list_empty(&info->receive_queue)) {
> + ret = list_first_entry(
> + &info->receive_queue,
> + struct smbd_response, list);
> + list_del(&ret->list);
> + info->count_receive_queue--;
> + info->count_get_receive_buffer++;
> + }
> + spin_unlock_irqrestore(&info->receive_queue_lock, flags);
> +
> + return ret;
> +}
> +
> +/*
> + * Return a receive buffer
> + * Upon returning of a receive buffer, we can post new receive and extend
> + * more receive credits to remote peer. This is done immediately after a
> + * receive buffer is returned.
> + */
> +static void put_receive_buffer(
> + struct smbd_connection *info, struct smbd_response *response,
> + bool lock)
> +{
> + unsigned long flags;
> +
> + ib_dma_unmap_single(info->id->device, response->sge.addr,
> + response->sge.length, DMA_FROM_DEVICE);
> +
> + if (lock)
> + spin_lock_irqsave(&info->receive_queue_lock, flags);
> + list_add_tail(&response->list, &info->receive_queue);
> + info->count_receive_queue++;
> + info->count_put_receive_buffer++;
> + if (lock)
> + spin_unlock_irqrestore(&info->receive_queue_lock, flags);
> +
> + queue_work(info->workqueue, &info->post_send_credits_work);
> +}
> +
> +/* Preallocate all receive buffer on transport establishment */
> +static int allocate_receive_buffers(struct smbd_connection *info, int num_buf)
> +{
> + int i;
> + struct smbd_response *response;
> +
> + INIT_LIST_HEAD(&info->reassembly_queue);
> + spin_lock_init(&info->reassembly_queue_lock);
> + info->reassembly_data_length = 0;
> + info->reassembly_queue_length = 0;
> +
> + INIT_LIST_HEAD(&info->receive_queue);
> + spin_lock_init(&info->receive_queue_lock);
> + info->count_receive_queue = 0;
> +
> + INIT_LIST_HEAD(&info->empty_packet_queue);
> + spin_lock_init(&info->empty_packet_queue_lock);
> + info->count_empty_packet_queue = 0;
> +
> + init_waitqueue_head(&info->wait_receive_queues);
> +
> + for (i = 0; i < num_buf; i++) {
> + response = mempool_alloc(info->response_mempool, GFP_KERNEL);
> + if (!response)
> + goto allocate_failed;
> +
> + response->info = info;
> + list_add_tail(&response->list, &info->receive_queue);
> + info->count_receive_queue++;
> + }
> +
> + return 0;
> +
> +allocate_failed:
> + while (!list_empty(&info->receive_queue)) {
> + response = list_first_entry(
> + &info->receive_queue,
> + struct smbd_response, list);
> + list_del(&response->list);
> + info->count_receive_queue--;
> +
> + mempool_free(response, info->response_mempool);
> + }
> + return -ENOMEM;
> +}
> +
> +static void destroy_receive_buffers(struct smbd_connection *info)
> +{
> + struct smbd_response *response;
> +
> + while ((response = get_receive_buffer(info)))
> + mempool_free(response, info->response_mempool);
> +
> + while ((response = get_empty_queue_buffer(info)))
> + mempool_free(response, info->response_mempool);
> +}
> +
> +/*
> + * Check and send an immediate or keep alive packet
> + * The condition to send those packets are defined in [MS-SMBD] 3.1.1.1
> + * Connection.KeepaliveRequested and Connection.SendImmediate
> + * The idea is to extend credits to server as soon as it becomes available
> + */
> +static void send_immediate_work(struct work_struct *work)
> +{
> + struct smbd_connection *info = container_of(
> + work, struct smbd_connection,
> + send_immediate_work.work);
> +
> + if (info->keep_alive_requested == KEEP_ALIVE_PENDING ||
> + info->send_immediate) {
> + log_keep_alive(INFO, "send an empty message\n");
> + smbd_post_send_empty(info);
> + }
> +}
> +
> +/* Implement idle connection timer [MS-SMBD] 3.1.6.2 */
> +static void idle_connection_timer(struct work_struct *work)
> +{
> + struct smbd_connection *info = container_of(
> + work, struct smbd_connection,
> + idle_timer_work.work);
> +
> + if (info->keep_alive_requested != KEEP_ALIVE_NONE) {
> + log_keep_alive(ERR,
> + "error status info->keep_alive_requested=%d\n",
> + info->keep_alive_requested);
> + smbd_disconnect_rdma_connection(info);
> + return;
> + }
> +
> + log_keep_alive(INFO, "about to send an empty idle message\n");
> + smbd_post_send_empty(info);
> +
> + /* Setup the next idle timeout work */
> + queue_delayed_work(info->workqueue, &info->idle_timer_work,
> + info->keep_alive_interval*HZ);
> +}
> +
> +static void destroy_caches_and_workqueue(struct smbd_connection *info)
> +{
> + destroy_receive_buffers(info);
> + destroy_workqueue(info->workqueue);
> + mempool_destroy(info->response_mempool);
> + kmem_cache_destroy(info->response_cache);
> + mempool_destroy(info->request_mempool);
> + kmem_cache_destroy(info->request_cache);
> +}
> +
> +#define MAX_NAME_LEN 80
> +static int allocate_caches_and_workqueue(struct smbd_connection *info)
> +{
> + char name[MAX_NAME_LEN];
> + int rc;
> +
> + snprintf(name, MAX_NAME_LEN, "smbd_request_%p", info);
> + info->request_cache =
> + kmem_cache_create(
> + name,
> + sizeof(struct smbd_request) +
> + sizeof(struct smbd_data_transfer),
> + 0, SLAB_HWCACHE_ALIGN, NULL);
> + if (!info->request_cache)
> + return -ENOMEM;
> +
> + info->request_mempool =
> + mempool_create(info->send_credit_target, mempool_alloc_slab,
> + mempool_free_slab, info->request_cache);
> + if (!info->request_mempool)
> + goto out1;
> +
> + snprintf(name, MAX_NAME_LEN, "smbd_response_%p", info);
> + info->response_cache =
> + kmem_cache_create(
> + name,
> + sizeof(struct smbd_response) +
> + info->max_receive_size,
> + 0, SLAB_HWCACHE_ALIGN, NULL);
> + if (!info->response_cache)
> + goto out2;
> +
> + info->response_mempool =
> + mempool_create(info->receive_credit_max, mempool_alloc_slab,
> + mempool_free_slab, info->response_cache);
> + if (!info->response_mempool)
> + goto out3;
> +
> + snprintf(name, MAX_NAME_LEN, "smbd_%p", info);
> + info->workqueue = create_workqueue(name);
> + if (!info->workqueue)
> + goto out4;
> +
> + rc = allocate_receive_buffers(info, info->receive_credit_max);
> + if (rc) {
> + log_rdma_event(ERR, "failed to allocate receive buffers\n");
> + goto out5;
> + }
> +
> + return 0;
> +
> +out5:
> + destroy_workqueue(info->workqueue);
> +out4:
> + mempool_destroy(info->response_mempool);
> +out3:
> + kmem_cache_destroy(info->response_cache);
> +out2:
> + mempool_destroy(info->request_mempool);
> +out1:
> + kmem_cache_destroy(info->request_cache);
> + return -ENOMEM;
> +}
> +
> +/* Create a SMBD connection, called by upper layer */
> +struct smbd_connection *_smbd_get_connection(
> + struct TCP_Server_Info *server, struct sockaddr *dstaddr, int port)
> +{
> + int rc;
> + struct smbd_connection *info;
> + struct rdma_conn_param conn_param;
> + struct ib_qp_init_attr qp_attr;
> + struct sockaddr_in *addr_in = (struct sockaddr_in *) dstaddr;
> +
> + info = kzalloc(sizeof(struct smbd_connection), GFP_KERNEL);
> + if (!info)
> + return NULL;
> +
> + info->transport_status = SMBD_CONNECTING;
> + rc = smbd_ia_open(info, dstaddr, port);
> + if (rc) {
> + log_rdma_event(INFO, "smbd_ia_open rc=%d\n", rc);
> + goto create_id_failed;
> + }
> +
> + if (smbd_send_credit_target > info->id->device->attrs.max_cqe ||
> + smbd_send_credit_target > info->id->device->attrs.max_qp_wr) {
> + log_rdma_event(ERR,
> + "consider lowering send_credit_target = %d. "
> + "Possible CQE overrun, device "
> + "reporting max_cpe %d max_qp_wr %d\n",
> + smbd_send_credit_target,
> + info->id->device->attrs.max_cqe,
> + info->id->device->attrs.max_qp_wr);
> + goto config_failed;
> + }
> +
> + if (smbd_receive_credit_max > info->id->device->attrs.max_cqe ||
> + smbd_receive_credit_max > info->id->device->attrs.max_qp_wr) {
> + log_rdma_event(ERR,
> + "consider lowering receive_credit_max = %d. "
> + "Possible CQE overrun, device "
> + "reporting max_cpe %d max_qp_wr %d\n",
> + smbd_receive_credit_max,
> + info->id->device->attrs.max_cqe,
> + info->id->device->attrs.max_qp_wr);
> + goto config_failed;
> + }
> +
> + info->receive_credit_max = smbd_receive_credit_max;
> + info->send_credit_target = smbd_send_credit_target;
> + info->max_send_size = smbd_max_send_size;
> + info->max_fragmented_recv_size = smbd_max_fragmented_recv_size;
> + info->max_receive_size = smbd_max_receive_size;
> + info->keep_alive_interval = smbd_keep_alive_interval;
> +
> + if (SMBDIRECT_MAX_SGE > info->id->device->attrs.max_sge) {
> + log_rdma_event(ERR, "warning: device max_sge = %d too small\n",
> + info->id->device->attrs.max_sge);
> + log_rdma_event(ERR, "Queue Pair creation may fail\n");
> + }
> +
> + info->send_cq = NULL;
> + info->recv_cq = NULL;
> + info->send_cq = ib_alloc_cq(info->id->device, info,
> + info->send_credit_target, 0, IB_POLL_SOFTIRQ);
> + if (IS_ERR(info->send_cq)) {
> + info->send_cq = NULL;
> + goto alloc_cq_failed;
> + }
> +
> + info->recv_cq = ib_alloc_cq(info->id->device, info,
> + info->receive_credit_max, 0, IB_POLL_SOFTIRQ);
> + if (IS_ERR(info->recv_cq)) {
> + info->recv_cq = NULL;
> + goto alloc_cq_failed;
> + }
> +
> + memset(&qp_attr, 0, sizeof(qp_attr));
> + qp_attr.event_handler = smbd_qp_async_error_upcall;
> + qp_attr.qp_context = info;
> + qp_attr.cap.max_send_wr = info->send_credit_target;
> + qp_attr.cap.max_recv_wr = info->receive_credit_max;
> + qp_attr.cap.max_send_sge = SMBDIRECT_MAX_SGE;
> + qp_attr.cap.max_recv_sge = SMBDIRECT_MAX_SGE;
> + qp_attr.cap.max_inline_data = 0;
> + qp_attr.sq_sig_type = IB_SIGNAL_REQ_WR;
> + qp_attr.qp_type = IB_QPT_RC;
> + qp_attr.send_cq = info->send_cq;
> + qp_attr.recv_cq = info->recv_cq;
> + qp_attr.port_num = ~0;
> +
> + rc = rdma_create_qp(info->id, info->pd, &qp_attr);
> + if (rc) {
> + log_rdma_event(ERR, "rdma_create_qp failed %i\n", rc);
> + goto create_qp_failed;
> + }
> +
> + memset(&conn_param, 0, sizeof(conn_param));
> + conn_param.initiator_depth = 0;
> +
> + conn_param.retry_count = SMBD_CM_RETRY;
> + conn_param.rnr_retry_count = SMBD_CM_RNR_RETRY;
> + conn_param.flow_control = 0;
> + init_waitqueue_head(&info->wait_destroy);
> +
> + log_rdma_event(INFO, "connecting to IP %pI4 port %d\n",
> + &addr_in->sin_addr, port);
> +
> + init_waitqueue_head(&info->conn_wait);
> + rc = rdma_connect(info->id, &conn_param);
> + if (rc) {
> + log_rdma_event(ERR, "rdma_connect() failed with %i\n", rc);
> + goto rdma_connect_failed;
> + }
> +
> + wait_event_interruptible(
> + info->conn_wait, info->transport_status != SMBD_CONNECTING);
> +
> + if (info->transport_status != SMBD_CONNECTED) {
> + log_rdma_event(ERR, "rdma_connect failed port=%d\n", port);
> + goto rdma_connect_failed;
> + }
> +
> + log_rdma_event(INFO, "rdma_connect connected\n");
> +
> + rc = allocate_caches_and_workqueue(info);
> + if (rc) {
> + log_rdma_event(ERR, "cache allocation failed\n");
> + goto allocate_cache_failed;
> + }
> +
> + init_waitqueue_head(&info->wait_send_queue);
> + init_waitqueue_head(&info->wait_reassembly_queue);
> +
> + INIT_DELAYED_WORK(&info->idle_timer_work, idle_connection_timer);
> + INIT_DELAYED_WORK(&info->send_immediate_work, send_immediate_work);
> + queue_delayed_work(info->workqueue, &info->idle_timer_work,
> + info->keep_alive_interval*HZ);
> +
> + init_waitqueue_head(&info->wait_send_pending);
> + atomic_set(&info->send_pending, 0);
> +
> + init_waitqueue_head(&info->wait_send_payload_pending);
> + atomic_set(&info->send_payload_pending, 0);
> +
> + INIT_WORK(&info->disconnect_work, smbd_disconnect_rdma_work);
> + INIT_WORK(&info->destroy_work, smbd_destroy_rdma_work);
> + INIT_WORK(&info->recv_done_work, smbd_recv_done_work);
> + INIT_WORK(&info->post_send_credits_work, smbd_post_send_credits);
> + info->new_credits_offered = 0;
> + spin_lock_init(&info->lock_new_credits_offered);
> +
> + rc = smbd_negotiate(info);
> + if (rc) {
> + log_rdma_event(ERR, "smbd_negotiate rc=%d\n", rc);
> + goto negotiation_failed;
> + }
> +
> + return info;
> +
> +negotiation_failed:
> + cancel_delayed_work_sync(&info->idle_timer_work);
> + destroy_caches_and_workqueue(info);
> + info->transport_status = SMBD_NEGOTIATE_FAILED;
> + init_waitqueue_head(&info->conn_wait);
> + rdma_disconnect(info->id);
> + wait_event(info->conn_wait,
> + info->transport_status == SMBD_DISCONNECTED);
> +
> +allocate_cache_failed:
> +rdma_connect_failed:
> + rdma_destroy_qp(info->id);
> +
> +create_qp_failed:
> +alloc_cq_failed:
> + if (info->send_cq)
> + ib_free_cq(info->send_cq);
> + if (info->recv_cq)
> + ib_free_cq(info->recv_cq);
> +
> +config_failed:
> + ib_dealloc_pd(info->pd);
> + rdma_destroy_id(info->id);
> +
> +create_id_failed:
> + kfree(info);
> + return NULL;
> +}
> diff --git a/fs/cifs/smbdirect.h b/fs/cifs/smbdirect.h
> index c55f28b..35bc25b 100644
> --- a/fs/cifs/smbdirect.h
> +++ b/fs/cifs/smbdirect.h
> @@ -16,6 +16,286 @@
> #ifndef _SMBDIRECT_H
> #define _SMBDIRECT_H
>
> +#ifdef CONFIG_CIFS_SMB_DIRECT
> +#define cifs_rdma_enabled(server) ((server)->rdma)
> +
> +#include "cifsglob.h"
> +#include <rdma/ib_verbs.h>
> +#include <rdma/rdma_cm.h>
> +#include <linux/mempool.h>
> +
> +enum keep_alive_status {
> + KEEP_ALIVE_NONE,
> + KEEP_ALIVE_PENDING,
> + KEEP_ALIVE_SENT,
> +};
> +
> +enum smbd_connection_status {
> + SMBD_CREATED,
> + SMBD_CONNECTING,
> + SMBD_CONNECTED,
> + SMBD_NEGOTIATE_FAILED,
> + SMBD_DISCONNECTING,
> + SMBD_DISCONNECTED,
> + SMBD_DESTROYED
> +};
> +
> +/*
> + * The context for the SMBDirect transport
> + * Everything related to the transport is here. It has several logical parts
> + * 1. RDMA related structures
> + * 2. SMBDirect connection parameters
> + * 3. Memory registrations
> + * 4. Receive and reassembly queues for data receive path
> + * 5. mempools for allocating packets
> + */
> +struct smbd_connection {
> + enum smbd_connection_status transport_status;
> +
> + /* RDMA related */
> + struct rdma_cm_id *id;
> + struct ib_qp_init_attr qp_attr;
> + struct ib_pd *pd;
> + struct ib_cq *send_cq, *recv_cq;
> + struct ib_device_attr dev_attr;
> + int ri_rc;
> + struct completion ri_done;
> + wait_queue_head_t conn_wait;
> + wait_queue_head_t wait_destroy;
> +
> + struct completion negotiate_completion;
> + bool negotiate_done;
> +
> + struct work_struct destroy_work;
> + struct work_struct disconnect_work;
> + struct work_struct recv_done_work;
> + struct work_struct post_send_credits_work;
> +
> + spinlock_t lock_new_credits_offered;
> + int new_credits_offered;
> +
> + /* Connection parameters defined in [MS-SMBD] 3.1.1.1 */
> + int receive_credit_max;
> + int send_credit_target;
> + int max_send_size;
> + int max_fragmented_recv_size;
> + int max_fragmented_send_size;
> + int max_receive_size;
> + int keep_alive_interval;
> + int max_readwrite_size;
> + enum keep_alive_status keep_alive_requested;
> + int protocol;
> + atomic_t send_credits;
> + atomic_t receive_credits;
> + int receive_credit_target;
> + int fragment_reassembly_remaining;
> +
> + /* Activity accoutning */
> +
> + atomic_t send_pending;
> + wait_queue_head_t wait_send_pending;
> + atomic_t send_payload_pending;
> + wait_queue_head_t wait_send_payload_pending;
> +
> + /* Receive queue */
> + struct list_head receive_queue;
> + int count_receive_queue;
> + spinlock_t receive_queue_lock;
> +
> + struct list_head empty_packet_queue;
> + int count_empty_packet_queue;
> + spinlock_t empty_packet_queue_lock;
> +
> + wait_queue_head_t wait_receive_queues;
> +
> + /* Reassembly queue */
> + struct list_head reassembly_queue;
> + spinlock_t reassembly_queue_lock;
> + wait_queue_head_t wait_reassembly_queue;
> +
> + /* total data length of reassembly queue */
> + int reassembly_data_length;
> + int reassembly_queue_length;
> + /* the offset to first buffer in reassembly queue */
> + int first_entry_offset;
> +
> + bool send_immediate;
> +
> + wait_queue_head_t wait_send_queue;
> +
> + /*
> + * Indicate if we have received a full packet on the connection
> + * This is used to identify the first SMBD packet of a assembled
> + * payload (SMB packet) in reassembly queue so we can return a
> + * RFC1002 length to upper layer to indicate the length of the SMB
> + * packet received
> + */
> + bool full_packet_received;
> +
> + struct workqueue_struct *workqueue;
> + struct delayed_work idle_timer_work;
> + struct delayed_work send_immediate_work;
> +
> + /* Memory pool for preallocating buffers */
> + /* request pool for RDMA send */
> + struct kmem_cache *request_cache;
> + mempool_t *request_mempool;
> +
> + /* response pool for RDMA receive */
> + struct kmem_cache *response_cache;
> + mempool_t *response_mempool;
> +
> + /* for debug purposes */
> + unsigned int count_get_receive_buffer;
> + unsigned int count_put_receive_buffer;
> + unsigned int count_reassembly_queue;
> + unsigned int count_enqueue_reassembly_queue;
> + unsigned int count_dequeue_reassembly_queue;
> + unsigned int count_send_empty;
> +};
> +
> +enum smbd_message_type {
> + SMBD_NEGOTIATE_RESP,
> + SMBD_TRANSFER_DATA,
> +};
> +
> +#define SMB_DIRECT_RESPONSE_REQUESTED 0x0001
> +
> +/* SMBD negotiation request packet [MS-SMBD] 2.2.1 */
> +struct smbd_negotiate_req {
> + __le16 min_version;
> + __le16 max_version;
> + __le16 reserved;
> + __le16 credits_requested;
> + __le32 preferred_send_size;
> + __le32 max_receive_size;
> + __le32 max_fragmented_size;
> +} __packed;
> +
> +/* SMBD negotiation response packet [MS-SMBD] 2.2.2 */
> +struct smbd_negotiate_resp {
> + __le16 min_version;
> + __le16 max_version;
> + __le16 negotiated_version;
> + __le16 reserved;
> + __le16 credits_requested;
> + __le16 credits_granted;
> + __le32 status;
> + __le32 max_readwrite_size;
> + __le32 preferred_send_size;
> + __le32 max_receive_size;
> + __le32 max_fragmented_size;
> +} __packed;
> +
> +/* SMBD data transfer packet with payload [MS-SMBD] 2.2.3 */
> +struct smbd_data_transfer {
> + __le16 credits_requested;
> + __le16 credits_granted;
> + __le16 flags;
> + __le16 reserved;
> + __le32 remaining_data_length;
> + __le32 data_offset;
> + __le32 data_length;
> + __le32 padding;
> + __u8 buffer[];
> +} __packed;
> +
> +/* The packet fields for a registered RDMA buffer */
> +struct smbd_buffer_descriptor_v1 {
> + __le64 offset;
> + __le32 token;
> + __le32 length;
> +} __packed;
> +
> /* Default maximum number of SGEs in a RDMA send/recv */
> #define SMBDIRECT_MAX_SGE 16
> +/* The context for a SMBD request */
> +struct smbd_request {
> + struct smbd_connection *info;
> + struct ib_cqe cqe;
> +
> + /* true if this request carries upper layer payload */
> + bool has_payload;
> +
> + /* the SGE entries for this packet */
> + struct ib_sge sge[SMBDIRECT_MAX_SGE];
> + int num_sge;
> +
> + /* SMBD packet header follows this structure */
> + u8 packet[];
> +};
> +
> +/* The context for a SMBD response */
> +struct smbd_response {
> + struct smbd_connection *info;
> + struct ib_cqe cqe;
> + struct ib_sge sge;
> +
> + enum smbd_message_type type;
> +
> + /* Link to receive queue or reassembly queue */
> + struct list_head list;
> +
> + /* Indicate if this is the 1st packet of a payload */
> + bool first_segment;
> +
> + /* SMBD packet header and payload follows this structure */
> + u8 packet[];
> +};
> +
> +/* Create a SMBDirect session */
> +struct smbd_connection *smbd_get_connection(
> + struct TCP_Server_Info *server, struct sockaddr *dstaddr);
> +
> +/* Reconnect SMBDirect session */
> +int smbd_reconnect(struct TCP_Server_Info *server);
> +
> +/* Destroy SMBDirect session */
> +void smbd_destroy(struct smbd_connection *info);
> +
> +/* Interface for carrying upper layer I/O through send/recv */
> +int smbd_recv(struct smbd_connection *info, struct msghdr *msg);
> +int smbd_send(struct smbd_connection *info, struct smb_rqst *rqst);
> +
> +enum mr_state {
> + MR_READY,
> + MR_REGISTERED,
> + MR_INVALIDATED,
> + MR_ERROR
> +};
> +
> +struct smbd_mr {
> + struct smbd_connection *conn;
> + struct list_head list;
> + enum mr_state state;
> + struct ib_mr *mr;
> + struct scatterlist *sgl;
> + int sgl_count;
> + enum dma_data_direction dir;
> + union {
> + struct ib_reg_wr wr;
> + struct ib_send_wr inv_wr;
> + };
> + struct ib_cqe cqe;
> + bool need_invalidate;
> + struct completion invalidate_done;
> +};
> +
> +/* Interfaces to register and deregister MR for RDMA read/write */
> +struct smbd_mr *smbd_register_mr(
> + struct smbd_connection *info, struct page *pages[], int num_pages,
> + int tailsz, bool writing, bool need_invalidate);
> +int smbd_deregister_mr(struct smbd_mr *mr);
> +
> +#else
> +#define cifs_rdma_enabled(server) 0
> +struct smbd_connection{};
> +static inline void *smbd_get_connection(
> + struct TCP_Server_Info *server, struct sockaddr *dstaddr) {return NULL;}
> +static inline int smbd_reconnect(struct TCP_Server_Info *server) {return -1;}
> +static inline void smbd_destroy(struct smbd_connection *info) {}
> +static inline int smbd_recv(struct smbd_connection *info, struct msghdr *msg) {return -1;}
> +static inline int smbd_send(struct smbd_connection *info, struct smb_rqst *rqst) {return -1;}
> +#endif
> +
> #endif
> --
> 2.7.4
>
> --
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