diff options
Diffstat (limited to 'fs/smb/client/smbdirect.c')
-rw-r--r-- | fs/smb/client/smbdirect.c | 2611 |
1 files changed, 2611 insertions, 0 deletions
diff --git a/fs/smb/client/smbdirect.c b/fs/smb/client/smbdirect.c new file mode 100644 index 000000000000..0362ebd4fa0f --- /dev/null +++ b/fs/smb/client/smbdirect.c @@ -0,0 +1,2611 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2017, Microsoft Corporation. + * + * Author(s): Long Li <longli@microsoft.com> + */ +#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 void destroy_mr_list(struct smbd_connection *info); +static int allocate_mr_list(struct smbd_connection *info); + +struct smb_extract_to_rdma { + struct ib_sge *sge; + unsigned int nr_sge; + unsigned int max_sge; + struct ib_device *device; + u32 local_dma_lkey; + enum dma_data_direction direction; +}; +static ssize_t smb_extract_iter_to_rdma(struct iov_iter *iter, size_t len, + struct smb_extract_to_rdma *rdma); + +/* 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 = 1364; + +/* 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 pages in a single 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) + +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; + wake_up_interruptible(&info->disconn_wait); + wake_up_interruptible(&info->wait_reassembly_queue); + wake_up_interruptible_all(&info->wait_send_queue); + 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); + break; + + 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 0x%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 (atomic_dec_and_test(&request->info->send_pending)) + wake_up(&request->info->wait_send_pending); + + wake_up(&request->info->wait_post_send); + + 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; +} + +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); + + /* Promptly send an immediate packet as defined in [MS-SMBD] 3.1.1.1 */ + info->send_immediate = true; + if (atomic_read(&info->receive_credits) < + info->receive_credit_target - 1) { + 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); + } + } +} + +/* 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=0x%p type=%d wc status=%d wc opcode %d byte_len=%d pkey_index=%u\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); + if (le16_to_cpu(data_transfer->credits_granted)) { + atomic_add(le16_to_cpu(data_transfer->credits_granted), + &info->send_credits); + /* + * We have new send credits granted from remote peer + * If any sender is waiting for credits, unblock it + */ + wake_up_interruptible(&info->wait_send_queue); + } + + 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; + } + + 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; + } + rc = wait_for_completion_interruptible_timeout( + &info->ri_done, msecs_to_jiffies(RDMA_RESOLVE_TIMEOUT)); + /* e.g. if interrupted returns -ERESTARTSYS */ + if (rc < 0) { + log_rdma_event(ERR, "rdma_resolve_addr timeout rc: %i\n", rc); + goto out; + } + 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; + } + rc = wait_for_completion_interruptible_timeout( + &info->ri_done, msecs_to_jiffies(RDMA_RESOLVE_TIMEOUT)); + /* e.g. if interrupted returns -ERESTARTSYS */ + if (rc < 0) { + log_rdma_event(ERR, "rdma_resolve_addr timeout rc: %i\n", rc); + goto out; + } + 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.kernel_cap_flags & IBK_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=0x%llx length=%u lkey=0x%x\n", + request->sge[0].addr, + request->sge[0].length, request->sge[0].lkey); + + 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; +} + +/* Post the send request */ +static int smbd_post_send(struct smbd_connection *info, + struct smbd_request *request) +{ + 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=0x%llx 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; + + rc = ib_post_send(info->id->qp, &send_wr, NULL); + if (rc) { + log_rdma_send(ERR, "ib_post_send failed rc=%d\n", rc); + smbd_disconnect_rdma_connection(info); + rc = -EAGAIN; + } 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_iter(struct smbd_connection *info, + struct iov_iter *iter, + int *_remaining_data_length) +{ + int i, rc; + int header_length; + int data_length; + struct smbd_request *request; + struct smbd_data_transfer *packet; + int new_credits = 0; + +wait_credit: + /* 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) + goto err_wait_credit; + + if (info->transport_status != SMBD_CONNECTED) { + log_outgoing(ERR, "disconnected not sending on wait_credit\n"); + rc = -EAGAIN; + goto err_wait_credit; + } + if (unlikely(atomic_dec_return(&info->send_credits) < 0)) { + atomic_inc(&info->send_credits); + goto wait_credit; + } + +wait_send_queue: + wait_event(info->wait_post_send, + atomic_read(&info->send_pending) < info->send_credit_target || + info->transport_status != SMBD_CONNECTED); + + if (info->transport_status != SMBD_CONNECTED) { + log_outgoing(ERR, "disconnected not sending on wait_send_queue\n"); + rc = -EAGAIN; + goto err_wait_send_queue; + } + + if (unlikely(atomic_inc_return(&info->send_pending) > + info->send_credit_target)) { + atomic_dec(&info->send_pending); + goto wait_send_queue; + } + + request = mempool_alloc(info->request_mempool, GFP_KERNEL); + if (!request) { + rc = -ENOMEM; + goto err_alloc; + } + + request->info = info; + memset(request->sge, 0, sizeof(request->sge)); + + /* Fill in the data payload to find out how much data we can add */ + if (iter) { + struct smb_extract_to_rdma extract = { + .nr_sge = 1, + .max_sge = SMBDIRECT_MAX_SEND_SGE, + .sge = request->sge, + .device = info->id->device, + .local_dma_lkey = info->pd->local_dma_lkey, + .direction = DMA_TO_DEVICE, + }; + + rc = smb_extract_iter_to_rdma(iter, *_remaining_data_length, + &extract); + if (rc < 0) + goto err_dma; + data_length = rc; + request->num_sge = extract.nr_sge; + *_remaining_data_length -= data_length; + } else { + data_length = 0; + request->num_sge = 1; + } + + /* Fill in the packet header */ + packet = smbd_request_payload(request); + packet->credits_requested = cpu_to_le16(info->send_credit_target); + + new_credits = manage_credits_prior_sending(info); + atomic_add(new_credits, &info->receive_credits); + packet->credits_granted = cpu_to_le16(new_credits); + + 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 (!data_length) + packet->data_offset = 0; + else + packet->data_offset = cpu_to_le32(24); + packet->data_length = cpu_to_le32(data_length); + 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 (!data_length) + header_length = offsetof(struct smbd_data_transfer, padding); + + request->sge[0].addr = ib_dma_map_single(info->id->device, + (void *)packet, + header_length, + DMA_TO_DEVICE); + if (ib_dma_mapping_error(info->id->device, request->sge[0].addr)) { + rc = -EIO; + request->sge[0].addr = 0; + goto err_dma; + } + + request->sge[0].length = header_length; + request->sge[0].lkey = info->pd->local_dma_lkey; + + rc = smbd_post_send(info, request); + if (!rc) + return 0; + +err_dma: + for (i = 0; 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); + mempool_free(request, info->request_mempool); + + /* roll back receive credits and credits to be offered */ + spin_lock(&info->lock_new_credits_offered); + info->new_credits_offered += new_credits; + spin_unlock(&info->lock_new_credits_offered); + atomic_sub(new_credits, &info->receive_credits); + +err_alloc: + if (atomic_dec_and_test(&info->send_pending)) + wake_up(&info->wait_send_pending); + +err_wait_send_queue: + /* roll back send credits and pending */ + atomic_inc(&info->send_credits); + +err_wait_credit: + 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) +{ + int remaining_data_length = 0; + + info->count_send_empty++; + return smbd_post_send_iter(info, NULL, &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=0x%llx iov.length=%u iov.lkey=0x%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 receiv |