// SPDX-License-Identifier: GPL-2.0-or-later /* * Copyright (C) 2017, Microsoft Corporation. * * Author(s): Long Li */ #include #include #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 empty 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 requires 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 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); } /* 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 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 */ void smbd_destroy(struct TCP_Server_Info *server) { struct smbd_connection *info = server->smbd_conn; struct smbd_response *response; unsigned long flags; if (!info) { log_rdma_event(INFO, "rdma session already destroyed\n"); return; } log_rdma_event(INFO, "destroying rdma session\n"); if (info->transport_status != SMBD_DISCONNECTED) { rdma_disconnect(server->smbd_conn->id); log_rdma_event(INFO, "wait for transport being disconnected\n"); wait_event_interruptible( info->disconn_wait, info->transport_status == SMBD_DISCONNECTED); } log_rdma_event(INFO, "destroying qp\n"); ib_drain_qp(info->id->qp); rdma_destroy_qp(info->id); log_rdma_event(INFO, "cancelling idle timer\n"); cancel_delayed_work_sync(&info->idle_timer_work); 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); /* It's not possible 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); /* * For performance reasons, memory registration and deregistration * are not locked by srv_mutex. It is possible some processes are * blocked on transport srv_mutex while holding memory registration. * Release the transport srv_mutex to allow them to hit the failure * path when sending data, and then release memory registartions. */ log_rdma_event(INFO, "freeing mr list\n"); wake_up_interruptible_all(&info->wait_mr); while (atomic_read(&info->mr_used_count)) { cifs_server_unlock(server); msleep(1000); cifs_server_lock(server); } destroy_mr_list(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; destroy_workqueue(info->workqueue); log_rdma_event(INFO, "rdma session destroyed\n"); kfree(info); server->smbd_conn = NULL; } /* * 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_destroy(server); } create_conn: log_rdma_event(INFO, "creating rdma session\n"); server->smbd_conn = smbd_get_connection( server, (struct sockaddr *) &server->dstaddr); if (server->smbd_conn) { cifs_dbg(VFS, "RDMA transport re-established\n"); trace_smb3_smbd_connect_done(server->hostname, server->conn_id, &server->dstaddr); return 0; } trace_smb3_smbd_connect_err(server->hostname, server->conn_id, &server->dstaddr); return -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; scnprintf(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; scnprintf(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; scnprintf(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_cqe %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_cqe %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_SEND_SGE || info->id->device->attrs.max_recv_sge < SMBDIRECT_MAX_RECV_SGE) { log_rdma_event(ERR, "device %.*s max_send_sge/max_recv_sge = %d/%d too small\n", IB_DEVICE_NAME_MAX, info->id->device->name, info->id->device->attrs.max_send_sge, info->id->device->attrs.max_recv_sge); goto config_failed; } info->send_cq = NULL; info->recv_cq = NULL; info->send_cq = ib_alloc_cq_any(info->id->device, info, info->send_credit_target, IB_POLL_SOFTIRQ); if (IS_ERR(info->send_cq)) { info->send_cq = NULL; goto alloc_cq_failed; } info->recv_cq = ib_alloc_cq_any(info->id->device, info, info->receive_credit_max, 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_SEND_SGE; qp_attr.cap.max_recv_sge = SMBDIRECT_MAX_RECV_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->ops.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; log_rdma_event(INFO, "connecting to IP %pI4 port %d\n", &addr_in->sin_addr, port); init_waitqueue_head(&info->conn_wait); init_waitqueue_head(&info->disconn_wait); init_waitqueue_head(&info->wait_reassembly_queue); 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_DELAYED_WORK(&info->idle_timer_work, idle_connection_timer); queue_delayed_work(info->workqueue, &info->idle_timer_work, info->keep_alive_interval*HZ); init_waitqueue_head(&info->wait_send_pending); atomic_set(&info->send_pending, 0); init_waitqueue_head(&info->wait_post_send); INIT_WORK(&info->disconnect_work, smbd_disconnect_rdma_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 */ server->smbd_conn = info; smbd_destroy(server); 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: /* * 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 rc; if (info->transport_status != SMBD_CONNECTED) { log_read(ERR, "disconnected\n"); return -ECONNABORTED; } 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; if (iov_iter_rw(&msg->msg_iter) == WRITE) { /* It's a bug in upper layer to get there */ cifs_dbg(VFS, "Invalid msg iter dir %u\n", iov_iter_rw(&msg->msg_iter)); rc = -EINVAL; goto out; } switch (iov_iter_type(&msg->msg_iter)) { case 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 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, "Invalid msg type %d\n", iov_iter_type(&msg->msg_iter)); rc = -EINVAL; } out: /* 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, int num_rqst, struct smb_rqst *rqst_array) { struct smbd_connection *info = server->smbd_conn; struct smb_rqst *rqst; struct iov_iter iter; unsigned int remaining_data_length, klen; int rc, i, rqst_idx; if (info->transport_status != SMBD_CONNECTED) return -EAGAIN; /* * 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 */ remaining_data_length = 0; for (i = 0; i < num_rqst; i++) remaining_data_length += smb_rqst_len(server, &rqst_array[i]); if (unlikely(remaining_data_length > info->max_fragmented_send_size)) { /* assertion: payload never exceeds negotiated maximum */ log_write(ERR, "payload size %d > max size %d\n", remaining_data_length, info->max_fragmented_send_size); return -EINVAL; } log_write(INFO, "num_rqst=%d total length=%u\n", num_rqst, remaining_data_length); rqst_idx = 0; do { rqst = &rqst_array[rqst_idx]; cifs_dbg(FYI, "Sending smb (RDMA): idx=%d smb_len=%lu\n", rqst_idx, smb_rqst_len(server, rqst)); for (i = 0; i < rqst->rq_nvec; i++) dump_smb(rqst->rq_iov[i].iov_base, rqst->rq_iov[i].iov_len); log_write(INFO, "RDMA-WR[%u] nvec=%d len=%u iter=%zu rqlen=%lu\n", rqst_idx, rqst->rq_nvec, remaining_data_length, iov_iter_count(&rqst->rq_iter), smb_rqst_len(server, rqst)); /* Send the metadata pages. */ klen = 0; for (i = 0; i < rqst->rq_nvec; i++) klen += rqst->rq_iov[i].iov_len; iov_iter_kvec(&iter, ITER_SOURCE, rqst->rq_iov, rqst->rq_nvec, klen); rc = smbd_post_send_iter(info, &iter, &remaining_data_length); if (rc < 0) break; if (iov_iter_count(&rqst->rq_iter) > 0) { /* And then the data pages if there are any */ rc = smbd_post_send_iter(info, &rqst->rq_iter, &remaining_data_length); if (rc < 0) break; } } while (++rqst_idx < num_rqst); /* * 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_pending, atomic_read(&info->send_pending) == 0); 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_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; } } else /* This MR is being used, don't recover it */ continue; 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->sgt.sgl, mr->sgt.nents, mr->dir); ib_dereg_mr(mr->mr); kfree(mr->sgt.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); INIT_WORK(&info->mr_recovery_work, smbd_mr_recovery_work); /* 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 cleanup_entries; 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->sgt.sgl = kcalloc(info->max_frmr_depth, sizeof(struct scatterlist), GFP_KERNEL); if (!smbdirect_mr->sgt.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); } return 0; out: kfree(smbdirect_mr); cleanup_entries: list_for_each_entry_safe(smbdirect_mr, tmp, &info->mr_list, list) { list_del(&smbdirect_mr->list); ib_dereg_mr(smbdirect_mr->mr); kfree(smbdirect_mr->sgt.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 * issuing 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; } /* * Transcribe the pages from an iterator into an MR scatterlist. */ static int smbd_iter_to_mr(struct smbd_connection *info, struct iov_iter *iter, struct sg_table *sgt, unsigned int max_sg) { int ret; memset(sgt->sgl, 0, max_sg * sizeof(struct scatterlist)); ret = extract_iter_to_sg(iter, iov_iter_count(iter), sgt, max_sg, 0); WARN_ON(ret < 0); if (sgt->nents > 0) sg_mark_end(&sgt->sgl[sgt->nents - 1]); return ret; } /* * Register memory for RDMA read/write * iter: the buffer to register memory with * 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 iov_iter *iter, bool writing, bool need_invalidate) { struct smbd_mr *smbdirect_mr; int rc, num_pages; enum dma_data_direction dir; struct ib_reg_wr *reg_wr; num_pages = iov_iter_npages(iter, info->max_frmr_depth + 1); 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); WARN_ON_ONCE(1); return NULL; } smbdirect_mr = get_mr(info); if (!smbdirect_mr) { log_rdma_mr(ERR, "get_mr returning NULL\n"); return NULL; } dir = writing ? DMA_FROM_DEVICE : DMA_TO_DEVICE; smbdirect_mr->dir = dir; smbdirect_mr->need_invalidate = need_invalidate; smbdirect_mr->sgt.nents = 0; smbdirect_mr->sgt.orig_nents = 0; log_rdma_mr(INFO, "num_pages=0x%x count=0x%zx depth=%u\n", num_pages, iov_iter_count(iter), info->max_frmr_depth); smbd_iter_to_mr(info, iter, &smbdirect_mr->sgt, info->max_frmr_depth); rc = ib_dma_map_sg(info->id->device, smbdirect_mr->sgt.sgl, smbdirect_mr->sgt.nents, 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->sgt.sgl, smbdirect_mr->sgt.nents, NULL, PAGE_SIZE); if (rc != smbdirect_mr->sgt.nents) { log_rdma_mr(ERR, "ib_map_mr_sg failed rc = %d nents = %x\n", rc, smbdirect_mr->sgt.nents); 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 actually 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->sgt.sgl, smbdirect_mr->sgt.nents, 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; if (smbdirect_mr->state == MR_INVALIDATED) { ib_dma_unmap_sg( info->id->device, smbdirect_mr->sgt.sgl, smbdirect_mr->sgt.nents, smbdirect_mr->dir); smbdirect_mr->state = MR_READY; if (atomic_inc_return(&info->mr_ready_count) == 1) wake_up_interruptible(&info->wait_mr); } else /* * Schedule the work to do MR recovery for future I/Os MR * recovery is slow and don't want it to block 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; } static bool smb_set_sge(struct smb_extract_to_rdma *rdma, struct page *lowest_page, size_t off, size_t len) { struct ib_sge *sge = &rdma->sge[rdma->nr_sge]; u64 addr; addr = ib_dma_map_page(rdma->device, lowest_page, off, len, rdma->direction); if (ib_dma_mapping_error(rdma->device, addr)) return false; sge->addr = addr; sge->length = len; sge->lkey = rdma->local_dma_lkey; rdma->nr_sge++; return true; } /* * Extract page fragments from a BVEC-class iterator and add them to an RDMA * element list. The pages are not pinned. */ static ssize_t smb_extract_bvec_to_rdma(struct iov_iter *iter, struct smb_extract_to_rdma *rdma, ssize_t maxsize) { const struct bio_vec *bv = iter->bvec; unsigned long start = iter->iov_offset; unsigned int i; ssize_t ret = 0; for (i = 0; i < iter->nr_segs; i++) { size_t off, len; len = bv[i].bv_len; if (start >= len) { start -= len; continue; } len = min_t(size_t, maxsize, len - start); off = bv[i].bv_offset + start; if (!smb_set_sge(rdma, bv[i].bv_page, off, len)) return -EIO; ret += len; maxsize -= len; if (rdma->nr_sge >= rdma->max_sge || maxsize <= 0) break; start = 0; } return ret; } /* * Extract fragments from a KVEC-class iterator and add them to an RDMA list. * This can deal with vmalloc'd buffers as well as kmalloc'd or static buffers. * The pages are not pinned. */ static ssize_t smb_extract_kvec_to_rdma(struct iov_iter *iter, struct smb_extract_to_rdma *rdma, ssize_t maxsize) { const struct kvec *kv = iter->kvec; unsigned long start = iter->iov_offset; unsigned int i; ssize_t ret = 0; for (i = 0; i < iter->nr_segs; i++) { struct page *page; unsigned long kaddr; size_t off, len, seg; len = kv[i].iov_len; if (start >= len) { start -= len; continue; } kaddr = (unsigned long)kv[i].iov_base + start; off = kaddr & ~PAGE_MASK; len = min_t(size_t, maxsize, len - start); kaddr &= PAGE_MASK; maxsize -= len; do { seg = min_t(size_t, len, PAGE_SIZE - off); if (is_vmalloc_or_module_addr((void *)kaddr)) page = vmalloc_to_page((void *)kaddr); else page = virt_to_page((void *)kaddr); if (!smb_set_sge(rdma, page, off, seg)) return -EIO; ret += seg; len -= seg; kaddr += PAGE_SIZE; off = 0; } while (len > 0 && rdma->nr_sge < rdma->max_sge); if (rdma->nr_sge >= rdma->max_sge || maxsize <= 0) break; start = 0; } return ret; } /* * Extract folio fragments from an XARRAY-class iterator and add them to an * RDMA list. The folios are not pinned. */ static ssize_t smb_extract_xarray_to_rdma(struct iov_iter *iter, struct smb_extract_to_rdma *rdma, ssize_t maxsize) { struct xarray *xa = iter->xarray; struct folio *folio; loff_t start = iter->xarray_start + iter->iov_offset; pgoff_t index = start / PAGE_SIZE; ssize_t ret = 0; size_t off, len; XA_STATE(xas, xa, index); rcu_read_lock(); xas_for_each(&xas, folio, ULONG_MAX) { if (xas_retry(&xas, folio)) continue; if (WARN_ON(xa_is_value(folio))) break; if (WARN_ON(folio_test_hugetlb(folio))) break; off = offset_in_folio(folio, start); len = min_t(size_t, maxsize, folio_size(folio) - off); if (!smb_set_sge(rdma, folio_page(folio, 0), off, len)) { rcu_read_unlock(); return -EIO; } maxsize -= len; ret += len; if (rdma->nr_sge >= rdma->max_sge || maxsize <= 0) break; } rcu_read_unlock(); return ret; } /* * Extract page fragments from up to the given amount of the source iterator * and build up an RDMA list that refers to all of those bits. The RDMA list * is appended to, up to the maximum number of elements set in the parameter * block. * * The extracted page fragments are not pinned or ref'd in any way; if an * IOVEC/UBUF-type iterator is to be used, it should be converted to a * BVEC-type iterator and the pages pinned, ref'd or otherwise held in some * way. */ static ssize_t smb_extract_iter_to_rdma(struct iov_iter *iter, size_t len, struct smb_extract_to_rdma *rdma) { ssize_t ret; int before = rdma->nr_sge; switch (iov_iter_type(iter)) { case ITER_BVEC: ret = smb_extract_bvec_to_rdma(iter, rdma, len); break; case ITER_KVEC: ret = smb_extract_kvec_to_rdma(iter, rdma, len); break; case ITER_XARRAY: ret = smb_extract_xarray_to_rdma(iter, rdma, len); break; default: WARN_ON_ONCE(1); return -EIO; } if (ret > 0) { iov_iter_advance(iter, ret); } else if (ret < 0) { while (rdma->nr_sge > before) { struct ib_sge *sge = &rdma->sge[rdma->nr_sge--]; ib_dma_unmap_single(rdma->device, sge->addr, sge->length, rdma->direction); sge->addr = 0; } } return ret; }