v4.19.13 snapshot.
diff --git a/fs/cifs/smbdirect.c b/fs/cifs/smbdirect.c
new file mode 100644
index 0000000..5fdb9a5
--- /dev/null
+++ b/fs/cifs/smbdirect.c
@@ -0,0 +1,2642 @@
+/*
+ * Copyright (C) 2017, Microsoft Corporation.
+ *
+ * Author(s): Long Li <longli@microsoft.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
+ * the GNU General Public License for more details.
+ */
+#include <linux/module.h>
+#include <linux/highmem.h>
+#include "smbdirect.h"
+#include "cifs_debug.h"
+#include "cifsproto.h"
+#include "smb2proto.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);
+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);
+static int smbd_post_send_data(
+ struct smbd_connection *info,
+ struct kvec *iov, int n_vec, int remaining_data_length);
+static int smbd_post_send_page(struct smbd_connection *info,
+ struct page *page, unsigned long offset,
+ size_t size, int remaining_data_length);
+
+static void destroy_mr_list(struct smbd_connection *info);
+static int allocate_mr_list(struct smbd_connection *info);
+
+/* SMBD version number */
+#define SMBD_V1 0x0100
+
+/* Port numbers for SMBD transport */
+#define SMB_PORT 445
+#define SMBD_PORT 5445
+
+/* Address lookup and resolve timeout in ms */
+#define RDMA_RESOLVE_TIMEOUT 5000
+
+/* SMBD negotiation timeout in seconds */
+#define SMBD_NEGOTIATE_TIMEOUT 120
+
+/* SMBD minimum receive size and fragmented sized defined in [MS-SMBD] */
+#define SMBD_MIN_RECEIVE_SIZE 128
+#define SMBD_MIN_FRAGMENTED_SIZE 131072
+
+/*
+ * Default maximum number of RDMA read/write outstanding on this connection
+ * This value is possibly decreased during QP creation on hardware limit
+ */
+#define SMBD_CM_RESPONDER_RESOURCES 32
+
+/* Maximum number of retries on data transfer operations */
+#define SMBD_CM_RETRY 6
+/* No need to retry on Receiver Not Ready since SMBD manages credits */
+#define SMBD_CM_RNR_RETRY 0
+
+/*
+ * User configurable initial values per SMBD transport connection
+ * as defined in [MS-SMBD] 3.1.1.1
+ * Those may change after a SMBD negotiation
+ */
+/* The local peer's maximum number of credits to grant to the peer */
+int smbd_receive_credit_max = 255;
+
+/* The remote peer's credit request of local peer */
+int smbd_send_credit_target = 255;
+
+/* The maximum single message size can be sent to remote peer */
+int smbd_max_send_size = 1364;
+
+/* The maximum fragmented upper-layer payload receive size supported */
+int smbd_max_fragmented_recv_size = 1024 * 1024;
+
+/* The maximum single-message size which can be received */
+int smbd_max_receive_size = 8192;
+
+/* The timeout to initiate send of a keepalive message on idle */
+int smbd_keep_alive_interval = 120;
+
+/*
+ * User configurable initial values for RDMA transport
+ * The actual values used may be lower and are limited to hardware capabilities
+ */
+/* Default maximum number of SGEs in a RDMA write/read */
+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=0xa0 will log all log_rdma_recv() and
+ * log_rdma_event()
+ */
+#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;
+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 send to finish\n");
+ wait_event(info->wait_smbd_send_pending,
+ info->smbd_send_pending == 0);
+
+ log_rdma_event(INFO, "wait for all recv to finish\n");
+ wake_up_interruptible(&info->wait_reassembly_queue);
+ wait_event(info->wait_smbd_recv_pending,
+ info->smbd_recv_pending == 0);
+
+ 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);
+
+ log_rdma_event(INFO, "freeing mr list\n");
+ wake_up_interruptible_all(&info->wait_mr);
+ wait_event(info->wait_for_mr_cleanup,
+ atomic_read(&info->mr_used_count) == 0);
+ destroy_mr_list(info);
+
+ /* 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);
+ } else
+ spin_unlock_irqrestore(&info->reassembly_queue_lock, flags);
+ } while (response);
+
+ 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)
+{
+ 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);
+ info->rdma_readwrite_threshold =
+ rdma_readwrite_threshold > info->max_fragmented_send_size ?
+ info->max_fragmented_send_size :
+ rdma_readwrite_threshold;
+
+
+ info->max_readwrite_size = min_t(u32,
+ le32_to_cpu(packet->max_readwrite_size),
+ info->max_frmr_depth * PAGE_SIZE);
+ info->max_frmr_depth = info->max_readwrite_size / PAGE_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);
+ 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);
+}
+
+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->max_frmr_depth = min_t(int,
+ smbd_max_frmr_depth,
+ info->id->device->attrs.max_fast_reg_page_list_len);
+ info->mr_type = IB_MR_TYPE_MEM_REG;
+ if (info->id->device->attrs.device_cap_flags & IB_DEVICE_SG_GAPS_REG)
+ info->mr_type = IB_MR_TYPE_SG_GAPS;
+
+ 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;
+ 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, NULL);
+ 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);
+
+ smbd_disconnect_rdma_connection(info);
+
+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;
+ int rc, i;
+
+ for (i = 0; i < request->num_sge; i++) {
+ log_rdma_send(INFO,
+ "rdma_request sge[%d] addr=%llu length=%u\n",
+ i, request->sge[i].addr, request->sge[i].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, NULL);
+ 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);
+ }
+ smbd_disconnect_rdma_connection(info);
+ } 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 a page
+ * page: the page to send
+ * offset: offset in the page to send
+ * size: length in the page to send
+ * remaining_data_length: remaining data to send in this payload
+ */
+static int smbd_post_send_page(struct smbd_connection *info, struct page *page,
+ unsigned long offset, size_t size, int remaining_data_length)
+{
+ struct scatterlist sgl;
+
+ sg_init_table(&sgl, 1);
+ sg_set_page(&sgl, page, size, offset);
+
+ return smbd_post_send_sgl(info, &sgl, size, remaining_data_length);
+}
+
+/*
+ * 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);
+}
+
+/*
+ * Send a data buffer
+ * iov: the iov array describing the data buffers
+ * n_vec: number of iov array
+ * remaining_data_length: remaining data to send following this packet
+ * in segmented SMBD packet
+ */
+static int smbd_post_send_data(
+ struct smbd_connection *info, struct kvec *iov, int n_vec,
+ int remaining_data_length)
+{
+ int i;
+ u32 data_length = 0;
+ struct scatterlist sgl[SMBDIRECT_MAX_SGE];
+
+ if (n_vec > SMBDIRECT_MAX_SGE) {
+ cifs_dbg(VFS, "Can't fit data to SGL, n_vec=%d\n", n_vec);
+ return -ENOMEM;
+ }
+
+ sg_init_table(sgl, n_vec);
+ for (i = 0; i < n_vec; i++) {
+ data_length += iov[i].iov_len;
+ sg_set_buf(&sgl[i], iov[i].iov_base, iov[i].iov_len);
+ }
+
+ return smbd_post_send_sgl(info, sgl, data_length, remaining_data_length);
+}
+
+/*
+ * 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;
+ 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, NULL);
+ if (rc) {
+ ib_dma_unmap_single(info->id->device, response->sge.addr,
+ response->sge.length, DMA_FROM_DEVICE);
+ smbd_disconnect_rdma_connection(info);
+ 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)
+{
+ unsigned long flags;
+
+ ib_dma_unmap_single(info->id->device, response->sge.addr,
+ response->sge.length, DMA_FROM_DEVICE);
+
+ 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++;
+ 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);
+}
+
+/* Destroy this SMBD connection, called from upper layer */
+void smbd_destroy(struct smbd_connection *info)
+{
+ log_rdma_event(INFO, "destroying rdma session\n");
+
+ /* Kick off the disconnection process */
+ smbd_disconnect_rdma_connection(info);
+
+ log_rdma_event(INFO, "wait for transport being destroyed\n");
+ wait_event(info->wait_destroy,
+ info->transport_status == SMBD_DESTROYED);
+
+ destroy_workqueue(info->workqueue);
+ kfree(info);
+}
+
+/*
+ * Reconnect this SMBD connection, called from upper layer
+ * return value: 0 on success, or actual error code
+ */
+int smbd_reconnect(struct TCP_Server_Info *server)
+{
+ log_rdma_event(INFO, "reconnecting rdma session\n");
+
+ if (!server->smbd_conn) {
+ log_rdma_event(INFO, "rdma session already destroyed\n");
+ goto create_conn;
+ }
+
+ /*
+ * This is possible if transport is disconnected and we haven't received
+ * notification from RDMA, but upper layer has detected timeout
+ */
+ if (server->smbd_conn->transport_status == SMBD_CONNECTED) {
+ log_rdma_event(INFO, "disconnecting transport\n");
+ smbd_disconnect_rdma_connection(server->smbd_conn);
+ }
+
+ /* wait until the transport is destroyed */
+ if (!wait_event_timeout(server->smbd_conn->wait_destroy,
+ server->smbd_conn->transport_status == SMBD_DESTROYED, 5*HZ))
+ return -EAGAIN;
+
+ destroy_workqueue(server->smbd_conn->workqueue);
+ kfree(server->smbd_conn);
+
+create_conn:
+ log_rdma_event(INFO, "creating rdma session\n");
+ server->smbd_conn = smbd_get_connection(
+ server, (struct sockaddr *) &server->dstaddr);
+ log_rdma_event(INFO, "created rdma session info=%p\n",
+ server->smbd_conn);
+
+ return server->smbd_conn ? 0 : -ENOENT;
+}
+
+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 */
+static 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;
+ struct ib_port_immutable port_immutable;
+ u32 ird_ord_hdr[2];
+
+ 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 (info->id->device->attrs.max_send_sge < SMBDIRECT_MAX_SGE) {
+ log_rdma_event(ERR,
+ "warning: device max_send_sge = %d too small\n",
+ info->id->device->attrs.max_send_sge);
+ log_rdma_event(ERR, "Queue Pair creation may fail\n");
+ }
+ if (info->id->device->attrs.max_recv_sge < SMBDIRECT_MAX_SGE) {
+ log_rdma_event(ERR,
+ "warning: device max_recv_sge = %d too small\n",
+ info->id->device->attrs.max_recv_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.responder_resources =
+ info->id->device->attrs.max_qp_rd_atom
+ < SMBD_CM_RESPONDER_RESOURCES ?
+ info->id->device->attrs.max_qp_rd_atom :
+ SMBD_CM_RESPONDER_RESOURCES;
+ info->responder_resources = conn_param.responder_resources;
+ log_rdma_mr(INFO, "responder_resources=%d\n",
+ info->responder_resources);
+
+ /* Need to send IRD/ORD in private data for iWARP */
+ info->id->device->get_port_immutable(
+ info->id->device, info->id->port_num, &port_immutable);
+ if (port_immutable.core_cap_flags & RDMA_CORE_PORT_IWARP) {
+ ird_ord_hdr[0] = info->responder_resources;
+ ird_ord_hdr[1] = 1;
+ conn_param.private_data = ird_ord_hdr;
+ conn_param.private_data_len = sizeof(ird_ord_hdr);
+ } else {
+ conn_param.private_data = NULL;
+ conn_param.private_data_len = 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_smbd_send_pending);
+ info->smbd_send_pending = 0;
+
+ init_waitqueue_head(&info->wait_smbd_recv_pending);
+ info->smbd_recv_pending = 0;
+
+ 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;
+ }
+
+ rc = allocate_mr_list(info);
+ if (rc) {
+ log_rdma_mr(ERR, "memory registration allocation failed\n");
+ goto allocate_mr_failed;
+ }
+
+ return info;
+
+allocate_mr_failed:
+ /* At this point, need to a full transport shutdown */
+ smbd_destroy(info);
+ return NULL;
+
+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;
+}
+
+struct smbd_connection *smbd_get_connection(
+ struct TCP_Server_Info *server, struct sockaddr *dstaddr)
+{
+ struct smbd_connection *ret;
+ int port = SMBD_PORT;
+
+try_again:
+ ret = _smbd_get_connection(server, dstaddr, port);
+
+ /* Try SMB_PORT if SMBD_PORT doesn't work */
+ if (!ret && port == SMBD_PORT) {
+ port = SMB_PORT;
+ goto try_again;
+ }
+ return ret;
+}
+
+/*
+ * Receive data from receive reassembly queue
+ * All the incoming data packets are placed in reassembly queue
+ * buf: the buffer to read data into
+ * size: the length of data to read
+ * return value: actual data read
+ * Note: this implementation copies the data from reassebmly queue to receive
+ * buffers used by upper layer. This is not the optimal code path. A better way
+ * to do it is to not have upper layer allocate its receive buffers but rather
+ * borrow the buffer from reassembly queue, and return it after data is
+ * consumed. But this will require more changes to upper layer code, and also
+ * need to consider packet boundaries while they still being reassembled.
+ */
+static int smbd_recv_buf(struct smbd_connection *info, char *buf,
+ unsigned int size)
+{
+ struct smbd_response *response;
+ struct smbd_data_transfer *data_transfer;
+ int to_copy, to_read, data_read, offset;
+ u32 data_length, remaining_data_length, data_offset;
+ int rc;
+
+again:
+ if (info->transport_status != SMBD_CONNECTED) {
+ log_read(ERR, "disconnected\n");
+ return -ENODEV;
+ }
+
+ /*
+ * No need to hold the reassembly queue lock all the time as we are
+ * the only one reading from the front of the queue. The transport
+ * may add more entries to the back of the queue at the same time
+ */
+ log_read(INFO, "size=%d info->reassembly_data_length=%d\n", size,
+ info->reassembly_data_length);
+ if (info->reassembly_data_length >= size) {
+ int queue_length;
+ int queue_removed = 0;
+
+ /*
+ * Need to make sure reassembly_data_length is read before
+ * reading reassembly_queue_length and calling
+ * _get_first_reassembly. This call is lock free
+ * as we never read at the end of the queue which are being
+ * updated in SOFTIRQ as more data is received
+ */
+ virt_rmb();
+ queue_length = info->reassembly_queue_length;
+ data_read = 0;
+ to_read = size;
+ offset = info->first_entry_offset;
+ while (data_read < size) {
+ response = _get_first_reassembly(info);
+ data_transfer = smbd_response_payload(response);
+ data_length = le32_to_cpu(data_transfer->data_length);
+ remaining_data_length =
+ le32_to_cpu(
+ data_transfer->remaining_data_length);
+ data_offset = le32_to_cpu(data_transfer->data_offset);
+
+ /*
+ * The upper layer expects RFC1002 length at the
+ * beginning of the payload. Return it to indicate
+ * the total length of the packet. This minimize the
+ * change to upper layer packet processing logic. This
+ * will be eventually remove when an intermediate
+ * transport layer is added
+ */
+ if (response->first_segment && size == 4) {
+ unsigned int rfc1002_len =
+ data_length + remaining_data_length;
+ *((__be32 *)buf) = cpu_to_be32(rfc1002_len);
+ data_read = 4;
+ response->first_segment = false;
+ log_read(INFO, "returning rfc1002 length %d\n",
+ rfc1002_len);
+ goto read_rfc1002_done;
+ }
+
+ to_copy = min_t(int, data_length - offset, to_read);
+ memcpy(
+ buf + data_read,
+ (char *)data_transfer + data_offset + offset,
+ to_copy);
+
+ /* move on to the next buffer? */
+ if (to_copy == data_length - offset) {
+ queue_length--;
+ /*
+ * No need to lock if we are not at the
+ * end of the queue
+ */
+ if (queue_length)
+ list_del(&response->list);
+ else {
+ spin_lock_irq(
+ &info->reassembly_queue_lock);
+ list_del(&response->list);
+ spin_unlock_irq(
+ &info->reassembly_queue_lock);
+ }
+ queue_removed++;
+ info->count_reassembly_queue--;
+ info->count_dequeue_reassembly_queue++;
+ put_receive_buffer(info, response);
+ offset = 0;
+ log_read(INFO, "put_receive_buffer offset=0\n");
+ } else
+ offset += to_copy;
+
+ to_read -= to_copy;
+ data_read += to_copy;
+
+ log_read(INFO, "_get_first_reassembly memcpy %d bytes "
+ "data_transfer_length-offset=%d after that "
+ "to_read=%d data_read=%d offset=%d\n",
+ to_copy, data_length - offset,
+ to_read, data_read, offset);
+ }
+
+ spin_lock_irq(&info->reassembly_queue_lock);
+ info->reassembly_data_length -= data_read;
+ info->reassembly_queue_length -= queue_removed;
+ spin_unlock_irq(&info->reassembly_queue_lock);
+
+ info->first_entry_offset = offset;
+ log_read(INFO, "returning to thread data_read=%d "
+ "reassembly_data_length=%d first_entry_offset=%d\n",
+ data_read, info->reassembly_data_length,
+ info->first_entry_offset);
+read_rfc1002_done:
+ return data_read;
+ }
+
+ log_read(INFO, "wait_event on more data\n");
+ rc = wait_event_interruptible(
+ info->wait_reassembly_queue,
+ info->reassembly_data_length >= size ||
+ info->transport_status != SMBD_CONNECTED);
+ /* Don't return any data if interrupted */
+ if (rc)
+ return -ENODEV;
+
+ goto again;
+}
+
+/*
+ * Receive a page from receive reassembly queue
+ * page: the page to read data into
+ * to_read: the length of data to read
+ * return value: actual data read
+ */
+static int smbd_recv_page(struct smbd_connection *info,
+ struct page *page, unsigned int page_offset,
+ unsigned int to_read)
+{
+ int ret;
+ char *to_address;
+ void *page_address;
+
+ /* make sure we have the page ready for read */
+ ret = wait_event_interruptible(
+ info->wait_reassembly_queue,
+ info->reassembly_data_length >= to_read ||
+ info->transport_status != SMBD_CONNECTED);
+ if (ret)
+ return ret;
+
+ /* now we can read from reassembly queue and not sleep */
+ page_address = kmap_atomic(page);
+ to_address = (char *) page_address + page_offset;
+
+ log_read(INFO, "reading from page=%p address=%p to_read=%d\n",
+ page, to_address, to_read);
+
+ ret = smbd_recv_buf(info, to_address, to_read);
+ kunmap_atomic(page_address);
+
+ return ret;
+}
+
+/*
+ * Receive data from transport
+ * msg: a msghdr point to the buffer, can be ITER_KVEC or ITER_BVEC
+ * return: total bytes read, or 0. SMB Direct will not do partial read.
+ */
+int smbd_recv(struct smbd_connection *info, struct msghdr *msg)
+{
+ char *buf;
+ struct page *page;
+ unsigned int to_read, page_offset;
+ int rc;
+
+ info->smbd_recv_pending++;
+
+ switch (msg->msg_iter.type) {
+ case READ | ITER_KVEC:
+ buf = msg->msg_iter.kvec->iov_base;
+ to_read = msg->msg_iter.kvec->iov_len;
+ rc = smbd_recv_buf(info, buf, to_read);
+ break;
+
+ case READ | ITER_BVEC:
+ page = msg->msg_iter.bvec->bv_page;
+ page_offset = msg->msg_iter.bvec->bv_offset;
+ to_read = msg->msg_iter.bvec->bv_len;
+ rc = smbd_recv_page(info, page, page_offset, to_read);
+ break;
+
+ default:
+ /* It's a bug in upper layer to get there */
+ cifs_dbg(VFS, "CIFS: invalid msg type %d\n",
+ msg->msg_iter.type);
+ rc = -EINVAL;
+ }
+
+ info->smbd_recv_pending--;
+ wake_up(&info->wait_smbd_recv_pending);
+
+ /* SMBDirect will read it all or nothing */
+ if (rc > 0)
+ msg->msg_iter.count = 0;
+ return rc;
+}
+
+/*
+ * Send data to transport
+ * Each rqst is transported as a SMBDirect payload
+ * rqst: the data to write
+ * return value: 0 if successfully write, otherwise error code
+ */
+int smbd_send(struct TCP_Server_Info *server, struct smb_rqst *rqst)
+{
+ struct smbd_connection *info = server->smbd_conn;
+ struct kvec vec;
+ int nvecs;
+ int size;
+ unsigned int buflen, remaining_data_length;
+ int start, i, j;
+ int max_iov_size =
+ info->max_send_size - sizeof(struct smbd_data_transfer);
+ struct kvec *iov;
+ int rc;
+
+ info->smbd_send_pending++;
+ if (info->transport_status != SMBD_CONNECTED) {
+ rc = -ENODEV;
+ goto done;
+ }
+
+ /*
+ * Skip the RFC1002 length defined in MS-SMB2 section 2.1
+ * It is used only for TCP transport in the iov[0]
+ * In future we may want to add a transport layer under protocol
+ * layer so this will only be issued to TCP transport
+ */
+
+ if (rqst->rq_iov[0].iov_len != 4) {
+ log_write(ERR, "expected the pdu length in 1st iov, but got %zu\n", rqst->rq_iov[0].iov_len);
+ return -EINVAL;
+ }
+
+ /*
+ * Add in the page array if there is one. The caller needs to set
+ * rq_tailsz to PAGE_SIZE when the buffer has multiple pages and
+ * ends at page boundary
+ */
+ buflen = smb_rqst_len(server, rqst);
+
+ if (buflen + sizeof(struct smbd_data_transfer) >
+ info->max_fragmented_send_size) {
+ log_write(ERR, "payload size %d > max size %d\n",
+ buflen, info->max_fragmented_send_size);
+ rc = -EINVAL;
+ goto done;
+ }
+
+ iov = &rqst->rq_iov[1];
+
+ cifs_dbg(FYI, "Sending smb (RDMA): smb_len=%u\n", buflen);
+ for (i = 0; i < rqst->rq_nvec-1; i++)
+ dump_smb(iov[i].iov_base, iov[i].iov_len);
+
+ remaining_data_length = buflen;
+
+ log_write(INFO, "rqst->rq_nvec=%d rqst->rq_npages=%d rq_pagesz=%d "
+ "rq_tailsz=%d buflen=%d\n",
+ rqst->rq_nvec, rqst->rq_npages, rqst->rq_pagesz,
+ rqst->rq_tailsz, buflen);
+
+ start = i = iov[0].iov_len ? 0 : 1;
+ buflen = 0;
+ while (true) {
+ buflen += iov[i].iov_len;
+ if (buflen > max_iov_size) {
+ if (i > start) {
+ remaining_data_length -=
+ (buflen-iov[i].iov_len);
+ log_write(INFO, "sending iov[] from start=%d "
+ "i=%d nvecs=%d "
+ "remaining_data_length=%d\n",
+ start, i, i-start,
+ remaining_data_length);
+ rc = smbd_post_send_data(
+ info, &iov[start], i-start,
+ remaining_data_length);
+ if (rc)
+ goto done;
+ } else {
+ /* iov[start] is too big, break it */
+ nvecs = (buflen+max_iov_size-1)/max_iov_size;
+ log_write(INFO, "iov[%d] iov_base=%p buflen=%d"
+ " break to %d vectors\n",
+ start, iov[start].iov_base,
+ buflen, nvecs);
+ for (j = 0; j < nvecs; j++) {
+ vec.iov_base =
+ (char *)iov[start].iov_base +
+ j*max_iov_size;
+ vec.iov_len = max_iov_size;
+ if (j == nvecs-1)
+ vec.iov_len =
+ buflen -
+ max_iov_size*(nvecs-1);
+ remaining_data_length -= vec.iov_len;
+ log_write(INFO,
+ "sending vec j=%d iov_base=%p"
+ " iov_len=%zu "
+ "remaining_data_length=%d\n",
+ j, vec.iov_base, vec.iov_len,
+ remaining_data_length);
+ rc = smbd_post_send_data(
+ info, &vec, 1,
+ remaining_data_length);
+ if (rc)
+ goto done;
+ }
+ i++;
+ if (i == rqst->rq_nvec-1)
+ break;
+ }
+ start = i;
+ buflen = 0;
+ } else {
+ i++;
+ if (i == rqst->rq_nvec-1) {
+ /* send out all remaining vecs */
+ remaining_data_length -= buflen;
+ log_write(INFO,
+ "sending iov[] from start=%d i=%d "
+ "nvecs=%d remaining_data_length=%d\n",
+ start, i, i-start,
+ remaining_data_length);
+ rc = smbd_post_send_data(info, &iov[start],
+ i-start, remaining_data_length);
+ if (rc)
+ goto done;
+ break;
+ }
+ }
+ log_write(INFO, "looping i=%d buflen=%d\n", i, buflen);
+ }
+
+ /* now sending pages if there are any */
+ for (i = 0; i < rqst->rq_npages; i++) {
+ unsigned int offset;
+
+ rqst_page_get_length(rqst, i, &buflen, &offset);
+ nvecs = (buflen + max_iov_size - 1) / max_iov_size;
+ log_write(INFO, "sending pages buflen=%d nvecs=%d\n",
+ buflen, nvecs);
+ for (j = 0; j < nvecs; j++) {
+ size = max_iov_size;
+ if (j == nvecs-1)
+ size = buflen - j*max_iov_size;
+ remaining_data_length -= size;
+ log_write(INFO, "sending pages i=%d offset=%d size=%d"
+ " remaining_data_length=%d\n",
+ i, j*max_iov_size+offset, size,
+ remaining_data_length);
+ rc = smbd_post_send_page(
+ info, rqst->rq_pages[i],
+ j*max_iov_size + offset,
+ size, remaining_data_length);
+ if (rc)
+ goto done;
+ }
+ }
+
+done:
+ /*
+ * As an optimization, we don't wait for individual I/O to finish
+ * before sending the next one.
+ * Send them all and wait for pending send count to get to 0
+ * that means all the I/Os have been out and we are good to return
+ */
+
+ wait_event(info->wait_send_payload_pending,
+ atomic_read(&info->send_payload_pending) == 0);
+
+ info->smbd_send_pending--;
+ wake_up(&info->wait_smbd_send_pending);
+
+ return rc;
+}
+
+static void register_mr_done(struct ib_cq *cq, struct ib_wc *wc)
+{
+ struct smbd_mr *mr;
+ struct ib_cqe *cqe;
+
+ if (wc->status) {
+ log_rdma_mr(ERR, "status=%d\n", wc->status);
+ cqe = wc->wr_cqe;
+ mr = container_of(cqe, struct smbd_mr, cqe);
+ smbd_disconnect_rdma_connection(mr->conn);
+ }
+}
+
+/*
+ * The work queue function that recovers MRs
+ * We need to call ib_dereg_mr() and ib_alloc_mr() before this MR can be used
+ * again. Both calls are slow, so finish them in a workqueue. This will not
+ * block I/O path.
+ * There is one workqueue that recovers MRs, there is no need to lock as the
+ * I/O requests calling smbd_register_mr will never update the links in the
+ * mr_list.
+ */
+static void smbd_mr_recovery_work(struct work_struct *work)
+{
+ struct smbd_connection *info =
+ container_of(work, struct smbd_connection, mr_recovery_work);
+ struct smbd_mr *smbdirect_mr;
+ int rc;
+
+ list_for_each_entry(smbdirect_mr, &info->mr_list, list) {
+ if (smbdirect_mr->state == MR_INVALIDATED ||
+ smbdirect_mr->state == MR_ERROR) {
+
+ /* recover this MR entry */
+ rc = ib_dereg_mr(smbdirect_mr->mr);
+ if (rc) {
+ log_rdma_mr(ERR,
+ "ib_dereg_mr failed rc=%x\n",
+ rc);
+ smbd_disconnect_rdma_connection(info);
+ continue;
+ }
+
+ smbdirect_mr->mr = ib_alloc_mr(
+ info->pd, info->mr_type,
+ info->max_frmr_depth);
+ if (IS_ERR(smbdirect_mr->mr)) {
+ log_rdma_mr(ERR,
+ "ib_alloc_mr failed mr_type=%x "
+ "max_frmr_depth=%x\n",
+ info->mr_type,
+ info->max_frmr_depth);
+ smbd_disconnect_rdma_connection(info);
+ continue;
+ }
+
+ if (smbdirect_mr->state == MR_INVALIDATED)
+ ib_dma_unmap_sg(
+ info->id->device, smbdirect_mr->sgl,
+ smbdirect_mr->sgl_count,
+ smbdirect_mr->dir);
+
+ smbdirect_mr->state = MR_READY;
+
+ /* smbdirect_mr->state is updated by this function
+ * and is read and updated by I/O issuing CPUs trying
+ * to get a MR, the call to atomic_inc_return
+ * implicates a memory barrier and guarantees this
+ * value is updated before waking up any calls to
+ * get_mr() from the I/O issuing CPUs
+ */
+ if (atomic_inc_return(&info->mr_ready_count) == 1)
+ wake_up_interruptible(&info->wait_mr);
+ }
+ }
+}
+
+static void destroy_mr_list(struct smbd_connection *info)
+{
+ struct smbd_mr *mr, *tmp;
+
+ cancel_work_sync(&info->mr_recovery_work);
+ list_for_each_entry_safe(mr, tmp, &info->mr_list, list) {
+ if (mr->state == MR_INVALIDATED)
+ ib_dma_unmap_sg(info->id->device, mr->sgl,
+ mr->sgl_count, mr->dir);
+ ib_dereg_mr(mr->mr);
+ kfree(mr->sgl);
+ kfree(mr);
+ }
+}
+
+/*
+ * Allocate MRs used for RDMA read/write
+ * The number of MRs will not exceed hardware capability in responder_resources
+ * All MRs are kept in mr_list. The MR can be recovered after it's used
+ * Recovery is done in smbd_mr_recovery_work. The content of list entry changes
+ * as MRs are used and recovered for I/O, but the list links will not change
+ */
+static int allocate_mr_list(struct smbd_connection *info)
+{
+ int i;
+ struct smbd_mr *smbdirect_mr, *tmp;
+
+ INIT_LIST_HEAD(&info->mr_list);
+ init_waitqueue_head(&info->wait_mr);
+ spin_lock_init(&info->mr_list_lock);
+ atomic_set(&info->mr_ready_count, 0);
+ atomic_set(&info->mr_used_count, 0);
+ init_waitqueue_head(&info->wait_for_mr_cleanup);
+ /* Allocate more MRs (2x) than hardware responder_resources */
+ for (i = 0; i < info->responder_resources * 2; i++) {
+ smbdirect_mr = kzalloc(sizeof(*smbdirect_mr), GFP_KERNEL);
+ if (!smbdirect_mr)
+ goto out;
+ smbdirect_mr->mr = ib_alloc_mr(info->pd, info->mr_type,
+ info->max_frmr_depth);
+ if (IS_ERR(smbdirect_mr->mr)) {
+ log_rdma_mr(ERR, "ib_alloc_mr failed mr_type=%x "
+ "max_frmr_depth=%x\n",
+ info->mr_type, info->max_frmr_depth);
+ goto out;
+ }
+ smbdirect_mr->sgl = kcalloc(
+ info->max_frmr_depth,
+ sizeof(struct scatterlist),
+ GFP_KERNEL);
+ if (!smbdirect_mr->sgl) {
+ log_rdma_mr(ERR, "failed to allocate sgl\n");
+ ib_dereg_mr(smbdirect_mr->mr);
+ goto out;
+ }
+ smbdirect_mr->state = MR_READY;
+ smbdirect_mr->conn = info;
+
+ list_add_tail(&smbdirect_mr->list, &info->mr_list);
+ atomic_inc(&info->mr_ready_count);
+ }
+ INIT_WORK(&info->mr_recovery_work, smbd_mr_recovery_work);
+ return 0;
+
+out:
+ kfree(smbdirect_mr);
+
+ list_for_each_entry_safe(smbdirect_mr, tmp, &info->mr_list, list) {
+ ib_dereg_mr(smbdirect_mr->mr);
+ kfree(smbdirect_mr->sgl);
+ kfree(smbdirect_mr);
+ }
+ return -ENOMEM;
+}
+
+/*
+ * Get a MR from mr_list. This function waits until there is at least one
+ * MR available in the list. It may access the list while the
+ * smbd_mr_recovery_work is recovering the MR list. This doesn't need a lock
+ * as they never modify the same places. However, there may be several CPUs
+ * issueing I/O trying to get MR at the same time, mr_list_lock is used to
+ * protect this situation.
+ */
+static struct smbd_mr *get_mr(struct smbd_connection *info)
+{
+ struct smbd_mr *ret;
+ int rc;
+again:
+ rc = wait_event_interruptible(info->wait_mr,
+ atomic_read(&info->mr_ready_count) ||
+ info->transport_status != SMBD_CONNECTED);
+ if (rc) {
+ log_rdma_mr(ERR, "wait_event_interruptible rc=%x\n", rc);
+ return NULL;
+ }
+
+ if (info->transport_status != SMBD_CONNECTED) {
+ log_rdma_mr(ERR, "info->transport_status=%x\n",
+ info->transport_status);
+ return NULL;
+ }
+
+ spin_lock(&info->mr_list_lock);
+ list_for_each_entry(ret, &info->mr_list, list) {
+ if (ret->state == MR_READY) {
+ ret->state = MR_REGISTERED;
+ spin_unlock(&info->mr_list_lock);
+ atomic_dec(&info->mr_ready_count);
+ atomic_inc(&info->mr_used_count);
+ return ret;
+ }
+ }
+
+ spin_unlock(&info->mr_list_lock);
+ /*
+ * It is possible that we could fail to get MR because other processes may
+ * try to acquire a MR at the same time. If this is the case, retry it.
+ */
+ goto again;
+}
+
+/*
+ * Register memory for RDMA read/write
+ * pages[]: the list of pages to register memory with
+ * num_pages: the number of pages to register
+ * tailsz: if non-zero, the bytes to register in the last page
+ * writing: true if this is a RDMA write (SMB read), false for RDMA read
+ * need_invalidate: true if this MR needs to be locally invalidated after I/O
+ * return value: the MR registered, NULL if failed.
+ */
+struct smbd_mr *smbd_register_mr(
+ struct smbd_connection *info, struct page *pages[], int num_pages,
+ int offset, int tailsz, bool writing, bool need_invalidate)
+{
+ struct smbd_mr *smbdirect_mr;
+ int rc, i;
+ enum dma_data_direction dir;
+ struct ib_reg_wr *reg_wr;
+
+ if (num_pages > info->max_frmr_depth) {
+ log_rdma_mr(ERR, "num_pages=%d max_frmr_depth=%d\n",
+ num_pages, info->max_frmr_depth);
+ return NULL;
+ }
+
+ smbdirect_mr = get_mr(info);
+ if (!smbdirect_mr) {
+ log_rdma_mr(ERR, "get_mr returning NULL\n");
+ return NULL;
+ }
+ smbdirect_mr->need_invalidate = need_invalidate;
+ smbdirect_mr->sgl_count = num_pages;
+ sg_init_table(smbdirect_mr->sgl, num_pages);
+
+ log_rdma_mr(INFO, "num_pages=0x%x offset=0x%x tailsz=0x%x\n",
+ num_pages, offset, tailsz);
+
+ if (num_pages == 1) {
+ sg_set_page(&smbdirect_mr->sgl[0], pages[0], tailsz, offset);
+ goto skip_multiple_pages;
+ }
+
+ /* We have at least two pages to register */
+ sg_set_page(
+ &smbdirect_mr->sgl[0], pages[0], PAGE_SIZE - offset, offset);
+ i = 1;
+ while (i < num_pages - 1) {
+ sg_set_page(&smbdirect_mr->sgl[i], pages[i], PAGE_SIZE, 0);
+ i++;
+ }
+ sg_set_page(&smbdirect_mr->sgl[i], pages[i],
+ tailsz ? tailsz : PAGE_SIZE, 0);
+
+skip_multiple_pages:
+ dir = writing ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
+ smbdirect_mr->dir = dir;
+ rc = ib_dma_map_sg(info->id->device, smbdirect_mr->sgl, num_pages, dir);
+ if (!rc) {
+ log_rdma_mr(ERR, "ib_dma_map_sg num_pages=%x dir=%x rc=%x\n",
+ num_pages, dir, rc);
+ goto dma_map_error;
+ }
+
+ rc = ib_map_mr_sg(smbdirect_mr->mr, smbdirect_mr->sgl, num_pages,
+ NULL, PAGE_SIZE);
+ if (rc != num_pages) {
+ log_rdma_mr(ERR,
+ "ib_map_mr_sg failed rc = %d num_pages = %x\n",
+ rc, num_pages);
+ goto map_mr_error;
+ }
+
+ ib_update_fast_reg_key(smbdirect_mr->mr,
+ ib_inc_rkey(smbdirect_mr->mr->rkey));
+ reg_wr = &smbdirect_mr->wr;
+ reg_wr->wr.opcode = IB_WR_REG_MR;
+ smbdirect_mr->cqe.done = register_mr_done;
+ reg_wr->wr.wr_cqe = &smbdirect_mr->cqe;
+ reg_wr->wr.num_sge = 0;
+ reg_wr->wr.send_flags = IB_SEND_SIGNALED;
+ reg_wr->mr = smbdirect_mr->mr;
+ reg_wr->key = smbdirect_mr->mr->rkey;
+ reg_wr->access = writing ?
+ IB_ACCESS_REMOTE_WRITE | IB_ACCESS_LOCAL_WRITE :
+ IB_ACCESS_REMOTE_READ;
+
+ /*
+ * There is no need for waiting for complemtion on ib_post_send
+ * on IB_WR_REG_MR. Hardware enforces a barrier and order of execution
+ * on the next ib_post_send when we actaully send I/O to remote peer
+ */
+ rc = ib_post_send(info->id->qp, ®_wr->wr, NULL);
+ if (!rc)
+ return smbdirect_mr;
+
+ log_rdma_mr(ERR, "ib_post_send failed rc=%x reg_wr->key=%x\n",
+ rc, reg_wr->key);
+
+ /* If all failed, attempt to recover this MR by setting it MR_ERROR*/
+map_mr_error:
+ ib_dma_unmap_sg(info->id->device, smbdirect_mr->sgl,
+ smbdirect_mr->sgl_count, smbdirect_mr->dir);
+
+dma_map_error:
+ smbdirect_mr->state = MR_ERROR;
+ if (atomic_dec_and_test(&info->mr_used_count))
+ wake_up(&info->wait_for_mr_cleanup);
+
+ smbd_disconnect_rdma_connection(info);
+
+ return NULL;
+}
+
+static void local_inv_done(struct ib_cq *cq, struct ib_wc *wc)
+{
+ struct smbd_mr *smbdirect_mr;
+ struct ib_cqe *cqe;
+
+ cqe = wc->wr_cqe;
+ smbdirect_mr = container_of(cqe, struct smbd_mr, cqe);
+ smbdirect_mr->state = MR_INVALIDATED;
+ if (wc->status != IB_WC_SUCCESS) {
+ log_rdma_mr(ERR, "invalidate failed status=%x\n", wc->status);
+ smbdirect_mr->state = MR_ERROR;
+ }
+ complete(&smbdirect_mr->invalidate_done);
+}
+
+/*
+ * Deregister a MR after I/O is done
+ * This function may wait if remote invalidation is not used
+ * and we have to locally invalidate the buffer to prevent data is being
+ * modified by remote peer after upper layer consumes it
+ */
+int smbd_deregister_mr(struct smbd_mr *smbdirect_mr)
+{
+ struct ib_send_wr *wr;
+ struct smbd_connection *info = smbdirect_mr->conn;
+ int rc = 0;
+
+ if (smbdirect_mr->need_invalidate) {
+ /* Need to finish local invalidation before returning */
+ wr = &smbdirect_mr->inv_wr;
+ wr->opcode = IB_WR_LOCAL_INV;
+ smbdirect_mr->cqe.done = local_inv_done;
+ wr->wr_cqe = &smbdirect_mr->cqe;
+ wr->num_sge = 0;
+ wr->ex.invalidate_rkey = smbdirect_mr->mr->rkey;
+ wr->send_flags = IB_SEND_SIGNALED;
+
+ init_completion(&smbdirect_mr->invalidate_done);
+ rc = ib_post_send(info->id->qp, wr, NULL);
+ if (rc) {
+ log_rdma_mr(ERR, "ib_post_send failed rc=%x\n", rc);
+ smbd_disconnect_rdma_connection(info);
+ goto done;
+ }
+ wait_for_completion(&smbdirect_mr->invalidate_done);
+ smbdirect_mr->need_invalidate = false;
+ } else
+ /*
+ * For remote invalidation, just set it to MR_INVALIDATED
+ * and defer to mr_recovery_work to recover the MR for next use
+ */
+ smbdirect_mr->state = MR_INVALIDATED;
+
+ /*
+ * Schedule the work to do MR recovery for future I/Os
+ * MR recovery is slow and we don't want it to block the current I/O
+ */
+ queue_work(info->workqueue, &info->mr_recovery_work);
+
+done:
+ if (atomic_dec_and_test(&info->mr_used_count))
+ wake_up(&info->wait_for_mr_cleanup);
+
+ return rc;
+}