diff options
Diffstat (limited to 'fs/cifs/smbdirect.c')
| -rw-r--r-- | fs/cifs/smbdirect.c | 2526 |
1 files changed, 2526 insertions, 0 deletions
diff --git a/fs/cifs/smbdirect.c b/fs/cifs/smbdirect.c new file mode 100644 index 000000000..7d18b9268 --- /dev/null +++ b/fs/cifs/smbdirect.c @@ -0,0 +1,2526 @@ +// 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 int smbd_post_send_data( + struct smbd_connection *info, + struct kvec *iov, int n_vec, int remaining_data_length); +static int smbd_post_send_page(struct smbd_connection *info, + struct page *page, unsigned long offset, + size_t size, int remaining_data_length); + +static void destroy_mr_list(struct smbd_connection *info); +static int allocate_mr_list(struct smbd_connection *info); + +/* SMBD version number */ +#define SMBD_V1 0x0100 + +/* Port numbers for SMBD transport */ +#define SMB_PORT 445 +#define SMBD_PORT 5445 + +/* Address lookup and resolve timeout in ms */ +#define RDMA_RESOLVE_TIMEOUT 5000 + +/* SMBD negotiation timeout in seconds */ +#define SMBD_NEGOTIATE_TIMEOUT 120 + +/* SMBD minimum receive size and fragmented sized defined in [MS-SMBD] */ +#define SMBD_MIN_RECEIVE_SIZE 128 +#define SMBD_MIN_FRAGMENTED_SIZE 131072 + +/* + * Default maximum number of RDMA read/write outstanding on this connection + * This value is possibly decreased during QP creation on hardware limit + */ +#define SMBD_CM_RESPONDER_RESOURCES 32 + +/* Maximum number of retries on data transfer operations */ +#define SMBD_CM_RETRY 6 +/* No need to retry on Receiver Not Ready since SMBD manages credits */ +#define SMBD_CM_RNR_RETRY 0 + +/* + * User configurable initial values per SMBD transport connection + * as defined in [MS-SMBD] 3.1.1.1 + * Those may change after a SMBD negotiation + */ +/* The local peer's maximum number of credits to grant to the peer */ +int smbd_receive_credit_max = 255; + +/* The remote peer's credit request of local peer */ +int smbd_send_credit_target = 255; + +/* The maximum single message size can be sent to remote peer */ +int smbd_max_send_size = 1364; + +/* The maximum fragmented upper-layer payload receive size supported */ +int smbd_max_fragmented_recv_size = 1024 * 1024; + +/* The maximum single-message size which can be received */ +int smbd_max_receive_size = 8192; + +/* The timeout to initiate send of a keepalive message on idle */ +int smbd_keep_alive_interval = 120; + +/* + * User configurable initial values for RDMA transport + * The actual values used may be lower and are limited to hardware capabilities + */ +/* Default maximum number of SGEs in a RDMA write/read */ +int smbd_max_frmr_depth = 2048; + +/* If payload is less than this byte, use RDMA send/recv not read/write */ +int rdma_readwrite_threshold = 4096; + +/* Transport logging functions + * Logging are defined as classes. They can be OR'ed to define the actual + * logging level via module parameter smbd_logging_class + * e.g. cifs.smbd_logging_class=0xa0 will log all log_rdma_recv() and + * log_rdma_event() + */ +#define LOG_OUTGOING 0x1 +#define LOG_INCOMING 0x2 +#define LOG_READ 0x4 +#define LOG_WRITE 0x8 +#define LOG_RDMA_SEND 0x10 +#define LOG_RDMA_RECV 0x20 +#define LOG_KEEP_ALIVE 0x40 +#define LOG_RDMA_EVENT 0x80 +#define LOG_RDMA_MR 0x100 +static unsigned int smbd_logging_class; +module_param(smbd_logging_class, uint, 0644); +MODULE_PARM_DESC(smbd_logging_class, + "Logging class for SMBD transport 0x0 to 0x100"); + +#define ERR 0x0 +#define INFO 0x1 +static unsigned int smbd_logging_level = ERR; +module_param(smbd_logging_level, uint, 0644); +MODULE_PARM_DESC(smbd_logging_level, + "Logging level for SMBD transport, 0 (default): error, 1: info"); + +#define log_rdma(level, class, fmt, args...) \ +do { \ + if (level <= smbd_logging_level || class & smbd_logging_class) \ + cifs_dbg(VFS, "%s:%d " fmt, __func__, __LINE__, ##args);\ +} while (0) + +#define log_outgoing(level, fmt, args...) \ + log_rdma(level, LOG_OUTGOING, fmt, ##args) +#define log_incoming(level, fmt, args...) \ + log_rdma(level, LOG_INCOMING, fmt, ##args) +#define log_read(level, fmt, args...) log_rdma(level, LOG_READ, fmt, ##args) +#define log_write(level, fmt, args...) log_rdma(level, LOG_WRITE, fmt, ##args) +#define log_rdma_send(level, fmt, args...) \ + log_rdma(level, LOG_RDMA_SEND, fmt, ##args) +#define log_rdma_recv(level, fmt, args...) \ + log_rdma(level, LOG_RDMA_RECV, fmt, ##args) +#define log_keep_alive(level, fmt, args...) \ + log_rdma(level, LOG_KEEP_ALIVE, fmt, ##args) +#define log_rdma_event(level, fmt, args...) \ + log_rdma(level, LOG_RDMA_EVENT, fmt, ##args) +#define log_rdma_mr(level, fmt, args...) \ + log_rdma(level, LOG_RDMA_MR, fmt, ##args) + +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); + + default: + break; + } +} + +static inline void *smbd_request_payload(struct smbd_request *request) +{ + return (void *)request->packet; +} + +static inline void *smbd_response_payload(struct smbd_response *response) +{ + return (void *)response->packet; +} + +/* Called when a RDMA send is done */ +static void send_done(struct ib_cq *cq, struct ib_wc *wc) +{ + int i; + struct smbd_request *request = + container_of(wc->wr_cqe, struct smbd_request, cqe); + + log_rdma_send(INFO, "smbd_request %p completed wc->status=%d\n", + request, wc->status); + + if (wc->status != IB_WC_SUCCESS || wc->opcode != IB_WC_SEND) { + log_rdma_send(ERR, "wc->status=%d wc->opcode=%d\n", + wc->status, wc->opcode); + smbd_disconnect_rdma_connection(request->info); + } + + for (i = 0; i < request->num_sge; i++) + ib_dma_unmap_single(request->info->id->device, + request->sge[i].addr, + request->sge[i].length, + DMA_TO_DEVICE); + + if (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=%p type=%d wc status=%d wc opcode %d byte_len=%d pkey_index=%x\n", + response, response->type, wc->status, wc->opcode, + wc->byte_len, wc->pkey_index); + + if (wc->status != IB_WC_SUCCESS || wc->opcode != IB_WC_RECV) { + log_rdma_recv(INFO, "wc->status=%d opcode=%d\n", + wc->status, wc->opcode); + smbd_disconnect_rdma_connection(info); + goto error; + } + + ib_dma_sync_single_for_cpu( + wc->qp->device, + response->sge.addr, + response->sge.length, + DMA_FROM_DEVICE); + + switch (response->type) { + /* SMBD negotiation response */ + case SMBD_NEGOTIATE_RESP: + dump_smbd_negotiate_resp(smbd_response_payload(response)); + info->full_packet_received = true; + info->negotiate_done = + process_negotiation_response(response, wc->byte_len); + complete(&info->negotiate_completion); + break; + + /* SMBD data transfer packet */ + case SMBD_TRANSFER_DATA: + data_transfer = smbd_response_payload(response); + data_length = le32_to_cpu(data_transfer->data_length); + + /* + * If this is a packet with data playload place the data in + * reassembly queue and wake up the reading thread + */ + if (data_length) { + if (info->full_packet_received) + response->first_segment = true; + + if (le32_to_cpu(data_transfer->remaining_data_length)) + info->full_packet_received = false; + else + info->full_packet_received = true; + + enqueue_reassembly( + info, + response, + data_length); + } else + put_empty_packet(info, response); + + if (data_length) + wake_up_interruptible(&info->wait_reassembly_queue); + + atomic_dec(&info->receive_credits); + info->receive_credit_target = + le16_to_cpu(data_transfer->credits_requested); + 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.device_cap_flags & IB_DEVICE_SG_GAPS_REG) + info->mr_type = IB_MR_TYPE_SG_GAPS; + + info->pd = ib_alloc_pd(info->id->device, 0); + if (IS_ERR(info->pd)) { + rc = PTR_ERR(info->pd); + log_rdma_event(ERR, "ib_alloc_pd() returned %d\n", rc); + goto out2; + } + + return 0; + +out2: + rdma_destroy_id(info->id); + info->id = NULL; + +out1: + return rc; +} + +/* + * Send a negotiation request message to the peer + * The negotiation procedure is in [MS-SMBD] 3.1.5.2 and 3.1.5.3 + * After negotiation, the transport is connected and ready for + * carrying upper layer SMB payload + */ +static int smbd_post_send_negotiate_req(struct smbd_connection *info) +{ + struct ib_send_wr send_wr; + int rc = -ENOMEM; + struct smbd_request *request; + struct smbd_negotiate_req *packet; + + request = mempool_alloc(info->request_mempool, GFP_KERNEL); + if (!request) + return rc; + + request->info = info; + + packet = smbd_request_payload(request); + packet->min_version = cpu_to_le16(SMBD_V1); + packet->max_version = cpu_to_le16(SMBD_V1); + packet->reserved = 0; + packet->credits_requested = cpu_to_le16(info->send_credit_target); + packet->preferred_send_size = cpu_to_le32(info->max_send_size); + packet->max_receive_size = cpu_to_le32(info->max_receive_size); + packet->max_fragmented_size = + cpu_to_le32(info->max_fragmented_recv_size); + + request->num_sge = 1; + request->sge[0].addr = ib_dma_map_single( + info->id->device, (void *)packet, + sizeof(*packet), DMA_TO_DEVICE); + if (ib_dma_mapping_error(info->id->device, request->sge[0].addr)) { + rc = -EIO; + goto dma_mapping_failed; + } + + request->sge[0].length = sizeof(*packet); + request->sge[0].lkey = info->pd->local_dma_lkey; + + ib_dma_sync_single_for_device( + info->id->device, request->sge[0].addr, + request->sge[0].length, DMA_TO_DEVICE); + + request->cqe.done = send_done; + + send_wr.next = NULL; + send_wr.wr_cqe = &request->cqe; + send_wr.sg_list = request->sge; + send_wr.num_sge = request->num_sge; + send_wr.opcode = IB_WR_SEND; + send_wr.send_flags = IB_SEND_SIGNALED; + + log_rdma_send(INFO, "sge addr=%llx length=%x lkey=%x\n", + request->sge[0].addr, + request->sge[0].length, request->sge[0].lkey); + + 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=%llu length=%u\n", + i, request->sge[i].addr, request->sge[i].length); + ib_dma_sync_single_for_device( + info->id->device, + request->sge[i].addr, + request->sge[i].length, + DMA_TO_DEVICE); + } + + request->cqe.done = send_done; + + send_wr.next = NULL; + send_wr.wr_cqe = &request->cqe; + send_wr.sg_list = request->sge; + send_wr.num_sge = request->num_sge; + send_wr.opcode = IB_WR_SEND; + send_wr.send_flags = IB_SEND_SIGNALED; + + 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_sgl(struct smbd_connection *info, + struct scatterlist *sgl, int data_length, int remaining_data_length) +{ + int num_sgs; + int i, rc; + int header_length; + struct smbd_request *request; + struct smbd_data_transfer *packet; + int new_credits; + struct scatterlist *sg; + +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; + + /* 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->num_sge = 1; + 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; + + /* Fill in the packet data payload */ + num_sgs = sgl ? sg_nents(sgl) : 0; + for_each_sg(sgl, sg, num_sgs, i) { + request->sge[i+1].addr = + ib_dma_map_page(info->id->device, sg_page(sg), + sg->offset, sg->length, DMA_TO_DEVICE); + if (ib_dma_mapping_error( + info->id->device, request->sge[i+1].addr)) { + rc = -EIO; + request->sge[i+1].addr = 0; + goto err_dma; + } + request->sge[i+1].length = sg->length; + request->sge[i+1].lkey = info->pd->local_dma_lkey; + request->num_sge++; + } + + rc = smbd_post_send(info, request); + 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 a page + * page: the page to send + * offset: offset in the page to send + * size: length in the page to send + * remaining_data_length: remaining data to send in this payload + */ +static int smbd_post_send_page(struct smbd_connection *info, struct page *page, + unsigned long offset, size_t size, int remaining_data_length) +{ + struct scatterlist sgl; + + sg_init_table(&sgl, 1); + sg_set_page(&sgl, page, size, offset); + + return smbd_post_send_sgl(info, &sgl, size, remaining_data_length); +} + +/* + * Send an empty message + * Empty message is used to extend credits to peer to for keep live + * while there is no upper layer payload to send at the time + */ +static int smbd_post_send_empty(struct smbd_connection *info) +{ + info->count_send_empty++; + return smbd_post_send_sgl(info, NULL, 0, 0); +} + +/* + * Send a data buffer + * iov: the iov array describing the data buffers + * n_vec: number of iov array + * remaining_data_length: remaining data to send following this packet + * in segmented SMBD packet + */ +static int smbd_post_send_data( + struct smbd_connection *info, struct kvec *iov, int n_vec, + int remaining_data_length) +{ + int i; + u32 data_length = 0; + struct scatterlist sgl[SMBDIRECT_MAX_SGE]; + + if (n_vec > SMBDIRECT_MAX_SGE) { + cifs_dbg(VFS, "Can't fit data to SGL, n_vec=%d\n", n_vec); + return -EINVAL; + } + + sg_init_table(sgl, n_vec); + for (i = 0; i < n_vec; i++) { + data_length += iov[i].iov_len; + sg_set_buf(&sgl[i], iov[i].iov_base, iov[i].iov_len); + } + + return smbd_post_send_sgl(info, sgl, data_length, remaining_data_length); +} + +/* + * Post a receive request to the transport + * The remote peer can only send data when a receive request is posted + * The interaction is controlled by send/receive credit system + */ +static int smbd_post_recv( + struct smbd_connection *info, struct smbd_response *response) +{ + struct ib_recv_wr recv_wr; + int rc = -EIO; + + response->sge.addr = ib_dma_map_single( + info->id->device, response->packet, + info->max_receive_size, DMA_FROM_DEVICE); + if (ib_dma_mapping_error(info->id->device, response->sge.addr)) + return rc; + + response->sge.length = info->max_receive_size; + response->sge.lkey = info->pd->local_dma_lkey; + + response->cqe.done = recv_done; + + recv_wr.wr_cqe = &response->cqe; + recv_wr.next = NULL; + recv_wr.sg_list = &response->sge; + recv_wr.num_sge = 1; + + rc = ib_post_recv(info->id->qp, &recv_wr, NULL); + if (rc) { + ib_dma_unmap_single(info->id->device, response->sge.addr, + response->sge.length, DMA_FROM_DEVICE); + smbd_disconnect_rdma_connection(info); + log_rdma_recv(ERR, "ib_post_recv failed rc=%d\n", rc); + } + + return rc; +} + +/* Perform SMBD negotiate according to [MS-SMBD] 3.1.5.2 */ +static int smbd_negotiate(struct smbd_connection *info) +{ + int rc; + struct smbd_response *response = get_receive_buffer(info); + + response->type = SMBD_NEGOTIATE_RESP; + rc = smbd_post_recv(info, response); + log_rdma_event(INFO, "smbd_post_recv rc=%d iov.addr=%llx iov.length=%x iov.lkey=%x\n", + rc, response->sge.addr, + response->sge.length, response->sge.lkey); + if (rc) + return rc; + + init_completion(&info->negotiate_completion); + info->negotiate_done = false; + rc = smbd_post_send_negotiate_req(info); + if (rc) + return rc; + + rc = wait_for_completion_interruptible_timeout( + &info->negotiate_completion, SMBD_NEGOTIATE_TIMEOUT * HZ); + log_rdma_event(INFO, "wait_for_completion_timeout rc=%d\n", rc); + + if (info->negotiate_done) + return 0; + + if (rc == 0) + rc = -ETIMEDOUT; + else if (rc == -ERESTARTSYS) + rc = -EINTR; + else + rc = -ENOTCONN; + + return rc; +} + +static void put_empty_packet( + struct smbd_connection *info, struct smbd_response *response) +{ + spin_lock(&info->empty_packet_queue_lock); + list_add_tail(&response->list, &info->empty_packet_queue); + info->count_empty_packet_queue++; + spin_unlock(&info->empty_packet_queue_lock); + + queue_work(info->workqueue, &info->post_send_credits_work); +} + +/* + * Implement Connection.FragmentReassemblyBuffer defined in [MS-SMBD] 3.1.1.1 + * This is a queue for reassembling upper layer payload and present to upper + * layer. All the inncoming payload go to the reassembly queue, regardless of + * if reassembly is required. The uuper layer code reads from the queue for all + * incoming payloads. + * Put a received packet to the reassembly queue + * response: the packet received + * data_length: the size of payload in this packet + */ +static void enqueue_reassembly( + struct smbd_connection *info, + struct smbd_response *response, + int data_length) +{ + spin_lock(&info->reassembly_queue_lock); + list_add_tail(&response->list, &info->reassembly_queue); + info->reassembly_queue_length++; + /* + * Make sure reassembly_data_length is updated after list and + * reassembly_queue_length are updated. On the dequeue side + * reassembly_data_length is checked without a lock to determine + * if reassembly_queue_length and list is up to date + */ + virt_wmb(); + info->reassembly_data_length += data_length; + spin_unlock(&info->reassembly_queue_lock); + info->count_reassembly_queue++; + info->count_enqueue_reassembly_queue++; +} + +/* + * Get the first entry at the front of reassembly queue + * Caller is responsible for locking + * return value: the first entry if any, NULL if queue is empty + */ +static struct smbd_response *_get_first_reassembly(struct smbd_connection *info) +{ + struct smbd_response *ret = NULL; + + if (!list_empty(&info->reassembly_queue)) { + ret = list_first_entry( + &info->reassembly_queue, + struct smbd_response, list); + } + return ret; +} + +static struct smbd_response *get_empty_queue_buffer( + struct smbd_connection *info) +{ + struct smbd_response *ret = NULL; + unsigned long flags; + + spin_lock_irqsave(&info->empty_packet_queue_lock, flags); + if (!list_empty(&info->empty_packet_queue)) { + ret = list_first_entry( + &info->empty_packet_queue, + struct smbd_response, list); + list_del(&ret->list); + info->count_empty_packet_queue--; + } + spin_unlock_irqrestore(&info->empty_packet_queue_lock, flags); + + return ret; +} + +/* + * Get a receive buffer + * For each remote send, we need to post a receive. The receive buffers are + * pre-allocated in advance. + * return value: the receive buffer, NULL if none is available + */ +static struct smbd_response *get_receive_buffer(struct smbd_connection *info) +{ + struct smbd_response *ret = NULL; + unsigned long flags; + + spin_lock_irqsave(&info->receive_queue_lock, flags); + if (!list_empty(&info->receive_queue)) { + ret = list_first_entry( + &info->receive_queue, + struct smbd_response, list); + list_del(&ret->list); + info->count_receive_queue--; + info->count_get_receive_buffer++; + } + spin_unlock_irqrestore(&info->receive_queue_lock, flags); + + return ret; +} + +/* + * Return a receive buffer + * Upon returning of a receive buffer, we can post new receive and extend + * more receive credits to remote peer. This is done immediately after a + * receive buffer is returned. + */ +static void put_receive_buffer( + struct smbd_connection *info, struct smbd_response *response) +{ + unsigned long flags; + + ib_dma_unmap_single(info->id->device, response->sge.addr, + response->sge.length, DMA_FROM_DEVICE); + + spin_lock_irqsave(&info->receive_queue_lock, flags); + list_add_tail(&response->list, &info->receive_queue); + info->count_receive_queue++; + info->count_put_receive_buffer++; + spin_unlock_irqrestore(&info->receive_queue_lock, flags); + + queue_work(info->workqueue, &info->post_send_credits_work); +} + +/* Preallocate all receive buffer on transport establishment */ +static int allocate_receive_buffers(struct smbd_connection *info, int num_buf) +{ + int i; + struct smbd_response *response; + + INIT_LIST_HEAD(&info->reassembly_queue); + spin_lock_init(&info->reassembly_queue_lock); + info->reassembly_data_length = 0; + info->reassembly_queue_length = 0; + + INIT_LIST_HEAD(&info->receive_queue); + spin_lock_init(&info->receive_queue_lock); + info->count_receive_queue = 0; + + INIT_LIST_HEAD(&info->empty_packet_queue); + spin_lock_init(&info->empty_packet_queue_lock); + info->count_empty_packet_queue = 0; + + init_waitqueue_head(&info->wait_receive_queues); + + for (i = 0; i < num_buf; i++) { + response = mempool_alloc(info->response_mempool, GFP_KERNEL); + if (!response) + goto allocate_failed; + + response->info = info; + list_add_tail(&response->list, &info->receive_queue); + info->count_receive_queue++; + } + + return 0; + +allocate_failed: + while (!list_empty(&info->receive_queue)) { + response = list_first_entry( + &info->receive_queue, + struct smbd_response, list); + list_del(&response->list); + info->count_receive_queue--; + + mempool_free(response, info->response_mempool); + } + return -ENOMEM; +} + +static void destroy_receive_buffers(struct smbd_connection *info) +{ + struct smbd_response *response; + + while ((response = get_receive_buffer(info))) + mempool_free(response, info->response_mempool); + + while ((response = get_empty_queue_buffer(info))) + mempool_free(response, info->response_mempool); +} + +/* 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 posssible for upper layer to get to reassembly */ + log_rdma_event(INFO, "drain the reassembly queue\n"); + do { + spin_lock_irqsave(&info->reassembly_queue_lock, flags); + response = _get_first_reassembly(info); + if (response) { + list_del(&response->list); + spin_unlock_irqrestore( + &info->reassembly_queue_lock, flags); + put_receive_buffer(info, response); + } else + spin_unlock_irqrestore( + &info->reassembly_queue_lock, flags); + } while (response); + info->reassembly_data_length = 0; + + log_rdma_event(INFO, "free receive buffers\n"); + wait_event(info->wait_receive_queues, + info->count_receive_queue + info->count_empty_packet_queue + == info->receive_credit_max); + destroy_receive_buffers(info); + + /* + * 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)) { + mutex_unlock(&server->srv_mutex); + msleep(1000); + mutex_lock(&server->srv_mutex); + } + 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"); + + return server->smbd_conn ? 0 : -ENOENT; +} + +static void destroy_caches_and_workqueue(struct smbd_connection *info) +{ + destroy_receive_buffers(info); + destroy_workqueue(info->workqueue); + mempool_destroy(info->response_mempool); + kmem_cache_destroy(info->response_cache); + mempool_destroy(info->request_mempool); + kmem_cache_destroy(info->request_cache); +} + +#define MAX_NAME_LEN 80 +static int allocate_caches_and_workqueue(struct smbd_connection *info) +{ + char name[MAX_NAME_LEN]; + int rc; + + 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_cpe %d max_qp_wr %d\n", + smbd_send_credit_target, + info->id->device->attrs.max_cqe, + info->id->device->attrs.max_qp_wr); + goto config_failed; + } + + if (smbd_receive_credit_max > info->id->device->attrs.max_cqe || + smbd_receive_credit_max > info->id->device->attrs.max_qp_wr) { + log_rdma_event(ERR, "consider lowering receive_credit_max = %d. Possible CQE overrun, device reporting max_cpe %d max_qp_wr %d\n", + smbd_receive_credit_max, + info->id->device->attrs.max_cqe, + info->id->device->attrs.max_qp_wr); + goto config_failed; + } + + info->receive_credit_max = smbd_receive_credit_max; + info->send_credit_target = smbd_send_credit_target; + info->max_send_size = smbd_max_send_size; + info->max_fragmented_recv_size = smbd_max_fragmented_recv_size; + info->max_receive_size = smbd_max_receive_size; + info->keep_alive_interval = smbd_keep_alive_interval; + + if (info->id->device->attrs.max_send_sge < SMBDIRECT_MAX_SGE) { + log_rdma_event(ERR, + "warning: device max_send_sge = %d too small\n", + info->id->device->attrs.max_send_sge); + log_rdma_event(ERR, "Queue Pair creation may fail\n"); + } + if (info->id->device->attrs.max_recv_sge < SMBDIRECT_MAX_SGE) { + log_rdma_event(ERR, + "warning: device max_recv_sge = %d too small\n", + info->id->device->attrs.max_recv_sge); + log_rdma_event(ERR, "Queue Pair creation may fail\n"); + } + + info->send_cq = NULL; + info->recv_cq = NULL; + info->send_cq = + ib_alloc_cq_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_SGE; + qp_attr.cap.max_recv_sge = SMBDIRECT_MAX_SGE; + qp_attr.cap.max_inline_data = 0; + qp_attr.sq_sig_type = IB_SIGNAL_REQ_WR; + qp_attr.qp_type = IB_QPT_RC; + qp_attr.send_cq = info->send_cq; + qp_attr.recv_cq = info->recv_cq; + qp_attr.port_num = ~0; + + rc = rdma_create_qp(info->id, info->pd, &qp_attr); + if (rc) { + log_rdma_event(ERR, "rdma_create_qp failed %i\n", rc); + goto create_qp_failed; + } + + memset(&conn_param, 0, sizeof(conn_param)); + conn_param.initiator_depth = 0; + + conn_param.responder_resources = + info->id->device->attrs.max_qp_rd_atom + < SMBD_CM_RESPONDER_RESOURCES ? + info->id->device->attrs.max_qp_rd_atom : + SMBD_CM_RESPONDER_RESOURCES; + info->responder_resources = conn_param.responder_resources; + log_rdma_mr(INFO, "responder_resources=%d\n", + info->responder_resources); + + /* Need to send IRD/ORD in private data for iWARP */ + info->id->device->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 kvec vec; + int nvecs; + int size; + unsigned int buflen, remaining_data_length; + int start, i, j; + int max_iov_size = + info->max_send_size - sizeof(struct smbd_data_transfer); + struct kvec *iov; + int rc; + struct smb_rqst *rqst; + int rqst_idx; + + if (info->transport_status != SMBD_CONNECTED) { + rc = -EAGAIN; + goto done; + } + + /* + * 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 (remaining_data_length > info->max_fragmented_send_size) { + log_write(ERR, "payload size %d > max size %d\n", + remaining_data_length, info->max_fragmented_send_size); + rc = -EINVAL; + goto done; + } + + log_write(INFO, "num_rqst=%d total length=%u\n", + num_rqst, remaining_data_length); + + rqst_idx = 0; +next_rqst: + rqst = &rqst_array[rqst_idx]; + iov = rqst->rq_iov; + + 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(iov[i].iov_base, iov[i].iov_len); + + + log_write(INFO, "rqst_idx=%d nvec=%d rqst->rq_npages=%d rq_pagesz=%d rq_tailsz=%d buflen=%lu\n", + rqst_idx, rqst->rq_nvec, rqst->rq_npages, rqst->rq_pagesz, + rqst->rq_tailsz, smb_rqst_len(server, rqst)); + + start = i = 0; + buflen = 0; + while (true) { + buflen += iov[i].iov_len; + if (buflen > max_iov_size) { + if (i > start) { + remaining_data_length -= + (buflen-iov[i].iov_len); + log_write(INFO, "sending iov[] from start=%d i=%d nvecs=%d remaining_data_length=%d\n", + start, i, i - start, + remaining_data_length); + rc = smbd_post_send_data( + info, &iov[start], i-start, + remaining_data_length); + if (rc) + goto done; + } else { + /* iov[start] is too big, break it */ + nvecs = (buflen+max_iov_size-1)/max_iov_size; + log_write(INFO, "iov[%d] iov_base=%p buflen=%d break to %d vectors\n", + start, iov[start].iov_base, + buflen, nvecs); + for (j = 0; j < nvecs; j++) { + vec.iov_base = + (char *)iov[start].iov_base + + j*max_iov_size; + vec.iov_len = max_iov_size; + if (j == nvecs-1) + vec.iov_len = + buflen - + max_iov_size*(nvecs-1); + remaining_data_length -= vec.iov_len; + log_write(INFO, + "sending vec j=%d iov_base=%p iov_len=%zu remaining_data_length=%d\n", + j, vec.iov_base, vec.iov_len, + remaining_data_length); + rc = smbd_post_send_data( + info, &vec, 1, + remaining_data_length); + if (rc) + goto done; + } + i++; + if (i == rqst->rq_nvec) + break; + } + start = i; + buflen = 0; + } else { + i++; + if (i == rqst->rq_nvec) { + /* send out all remaining vecs */ + remaining_data_length -= buflen; + log_write(INFO, "sending iov[] from start=%d i=%d nvecs=%d remaining_data_length=%d\n", + start, i, i - start, + remaining_data_length); + rc = smbd_post_send_data(info, &iov[start], + i-start, remaining_data_length); + if (rc) + goto done; + break; + } + } + log_write(INFO, "looping i=%d buflen=%d\n", i, buflen); + } + + /* now sending pages if there are any */ + for (i = 0; i < rqst->rq_npages; i++) { + unsigned int offset; + + rqst_page_get_length(rqst, i, &buflen, &offset); + nvecs = (buflen + max_iov_size - 1) / max_iov_size; + log_write(INFO, "sending pages buflen=%d nvecs=%d\n", + buflen, nvecs); + for (j = 0; j < nvecs; j++) { + size = max_iov_size; + if (j == nvecs-1) + size = buflen - j*max_iov_size; + remaining_data_length -= size; + log_write(INFO, "sending pages i=%d offset=%d size=%d remaining_data_length=%d\n", + i, j * max_iov_size + offset, size, + remaining_data_length); + rc = smbd_post_send_page( + info, rqst->rq_pages[i], + j*max_iov_size + offset, + size, remaining_data_length); + if (rc) + goto done; + } + } + + rqst_idx++; + if (rqst_idx < num_rqst) + goto next_rqst; + +done: + /* + * As an optimization, we don't wait for individual I/O to finish + * before sending the next one. + * Send them all and wait for pending send count to get to 0 + * that means all the I/Os have been out and we are good to return + */ + + wait_event(info->wait_send_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->sgl, + mr->sgl_count, mr->dir); + ib_dereg_mr(mr->mr); + kfree(mr->sgl); + kfree(mr); + } +} + +/* + * Allocate MRs used for RDMA read/write + * The number of MRs will not exceed hardware capability in responder_resources + * All MRs are kept in mr_list. The MR can be recovered after it's used + * Recovery is done in smbd_mr_recovery_work. The content of list entry changes + * as MRs are used and recovered for I/O, but the list links will not change + */ +static int allocate_mr_list(struct smbd_connection *info) +{ + int i; + struct smbd_mr *smbdirect_mr, *tmp; + + INIT_LIST_HEAD(&info->mr_list); + init_waitqueue_head(&info->wait_mr); + spin_lock_init(&info->mr_list_lock); + atomic_set(&info->mr_ready_count, 0); + atomic_set(&info->mr_used_count, 0); + init_waitqueue_head(&info->wait_for_mr_cleanup); + 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 out; + smbdirect_mr->mr = ib_alloc_mr(info->pd, info->mr_type, + info->max_frmr_depth); + if (IS_ERR(smbdirect_mr->mr)) { + log_rdma_mr(ERR, "ib_alloc_mr failed mr_type=%x max_frmr_depth=%x\n", + info->mr_type, info->max_frmr_depth); + goto out; + } + smbdirect_mr->sgl = kcalloc( + info->max_frmr_depth, + sizeof(struct scatterlist), + GFP_KERNEL); + if (!smbdirect_mr->sgl) { + log_rdma_mr(ERR, "failed to allocate sgl\n"); + ib_dereg_mr(smbdirect_mr->mr); + goto out; + } + smbdirect_mr->state = MR_READY; + smbdirect_mr->conn = info; + + list_add_tail(&smbdirect_mr->list, &info->mr_list); + atomic_inc(&info->mr_ready_count); + } + return 0; + +out: + kfree(smbdirect_mr); + + 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->sgl); + kfree(smbdirect_mr); + } + return -ENOMEM; +} + +/* + * Get a MR from mr_list. This function waits until there is at least one + * MR available in the list. It may access the list while the + * smbd_mr_recovery_work is recovering the MR list. This doesn't need a lock + * as they never modify the same places. However, there may be several CPUs + * issueing I/O trying to get MR at the same time, mr_list_lock is used to + * protect this situation. + */ +static struct smbd_mr *get_mr(struct smbd_connection *info) +{ + struct smbd_mr *ret; + int rc; +again: + rc = wait_event_interruptible(info->wait_mr, + atomic_read(&info->mr_ready_count) || + info->transport_status != SMBD_CONNECTED); + if (rc) { + log_rdma_mr(ERR, "wait_event_interruptible rc=%x\n", rc); + return NULL; + } + + if (info->transport_status != SMBD_CONNECTED) { + log_rdma_mr(ERR, "info->transport_status=%x\n", + info->transport_status); + return NULL; + } + + spin_lock(&info->mr_list_lock); + list_for_each_entry(ret, &info->mr_list, list) { + if (ret->state == MR_READY) { + ret->state = MR_REGISTERED; + spin_unlock(&info->mr_list_lock); + atomic_dec(&info->mr_ready_count); + atomic_inc(&info->mr_used_count); + return ret; + } + } + + spin_unlock(&info->mr_list_lock); + /* + * It is possible that we could fail to get MR because other processes may + * try to acquire a MR at the same time. If this is the case, retry it. + */ + goto again; +} + +/* + * Register memory for RDMA read/write + * pages[]: the list of pages to register memory with + * num_pages: the number of pages to register + * tailsz: if non-zero, the bytes to register in the last page + * writing: true if this is a RDMA write (SMB read), false for RDMA read + * need_invalidate: true if this MR needs to be locally invalidated after I/O + * return value: the MR registered, NULL if failed. + */ +struct smbd_mr *smbd_register_mr( + struct smbd_connection *info, struct page *pages[], int num_pages, + int offset, int tailsz, bool writing, bool need_invalidate) +{ + struct smbd_mr *smbdirect_mr; + int rc, i; + enum dma_data_direction dir; + struct ib_reg_wr *reg_wr; + + if (num_pages > info->max_frmr_depth) { + log_rdma_mr(ERR, "num_pages=%d max_frmr_depth=%d\n", + num_pages, info->max_frmr_depth); + return NULL; + } + + smbdirect_mr = get_mr(info); + if (!smbdirect_mr) { + log_rdma_mr(ERR, "get_mr returning NULL\n"); + return NULL; + } + smbdirect_mr->need_invalidate = need_invalidate; + smbdirect_mr->sgl_count = num_pages; + sg_init_table(smbdirect_mr->sgl, num_pages); + + log_rdma_mr(INFO, "num_pages=0x%x offset=0x%x tailsz=0x%x\n", + num_pages, offset, tailsz); + + if (num_pages == 1) { + sg_set_page(&smbdirect_mr->sgl[0], pages[0], tailsz, offset); + goto skip_multiple_pages; + } + + /* We have at least two pages to register */ + sg_set_page( + &smbdirect_mr->sgl[0], pages[0], PAGE_SIZE - offset, offset); + i = 1; + while (i < num_pages - 1) { + sg_set_page(&smbdirect_mr->sgl[i], pages[i], PAGE_SIZE, 0); + i++; + } + sg_set_page(&smbdirect_mr->sgl[i], pages[i], + tailsz ? tailsz : PAGE_SIZE, 0); + +skip_multiple_pages: + dir = writing ? DMA_FROM_DEVICE : DMA_TO_DEVICE; + smbdirect_mr->dir = dir; + rc = ib_dma_map_sg(info->id->device, smbdirect_mr->sgl, num_pages, dir); + if (!rc) { + log_rdma_mr(ERR, "ib_dma_map_sg num_pages=%x dir=%x rc=%x\n", + num_pages, dir, rc); + goto dma_map_error; + } + + rc = ib_map_mr_sg(smbdirect_mr->mr, smbdirect_mr->sgl, num_pages, + NULL, PAGE_SIZE); + if (rc != num_pages) { + log_rdma_mr(ERR, + "ib_map_mr_sg failed rc = %d num_pages = %x\n", + rc, num_pages); + goto map_mr_error; + } + + ib_update_fast_reg_key(smbdirect_mr->mr, + ib_inc_rkey(smbdirect_mr->mr->rkey)); + reg_wr = &smbdirect_mr->wr; + reg_wr->wr.opcode = IB_WR_REG_MR; + smbdirect_mr->cqe.done = register_mr_done; + reg_wr->wr.wr_cqe = &smbdirect_mr->cqe; + reg_wr->wr.num_sge = 0; + reg_wr->wr.send_flags = IB_SEND_SIGNALED; + reg_wr->mr = smbdirect_mr->mr; + reg_wr->key = smbdirect_mr->mr->rkey; + reg_wr->access = writing ? + IB_ACCESS_REMOTE_WRITE | IB_ACCESS_LOCAL_WRITE : + IB_ACCESS_REMOTE_READ; + + /* + * There is no need for waiting for complemtion on ib_post_send + * on IB_WR_REG_MR. Hardware enforces a barrier and order of execution + * on the next ib_post_send when we actaully send I/O to remote peer + */ + rc = ib_post_send(info->id->qp, ®_wr->wr, NULL); + if (!rc) + return smbdirect_mr; + + log_rdma_mr(ERR, "ib_post_send failed rc=%x reg_wr->key=%x\n", + rc, reg_wr->key); + + /* If all failed, attempt to recover this MR by setting it MR_ERROR*/ +map_mr_error: + ib_dma_unmap_sg(info->id->device, smbdirect_mr->sgl, + smbdirect_mr->sgl_count, smbdirect_mr->dir); + +dma_map_error: + smbdirect_mr->state = MR_ERROR; + if (atomic_dec_and_test(&info->mr_used_count)) + wake_up(&info->wait_for_mr_cleanup); + + smbd_disconnect_rdma_connection(info); + + return NULL; +} + +static void local_inv_done(struct ib_cq *cq, struct ib_wc *wc) +{ + struct smbd_mr *smbdirect_mr; + struct ib_cqe *cqe; + + cqe = wc->wr_cqe; + smbdirect_mr = container_of(cqe, struct smbd_mr, cqe); + smbdirect_mr->state = MR_INVALIDATED; + if (wc->status != IB_WC_SUCCESS) { + log_rdma_mr(ERR, "invalidate failed status=%x\n", wc->status); + smbdirect_mr->state = MR_ERROR; + } + complete(&smbdirect_mr->invalidate_done); +} + +/* + * Deregister a MR after I/O is done + * This function may wait if remote invalidation is not used + * and we have to locally invalidate the buffer to prevent data is being + * modified by remote peer after upper layer consumes it + */ +int smbd_deregister_mr(struct smbd_mr *smbdirect_mr) +{ + struct ib_send_wr *wr; + struct smbd_connection *info = smbdirect_mr->conn; + int rc = 0; + + if (smbdirect_mr->need_invalidate) { + /* Need to finish local invalidation before returning */ + wr = &smbdirect_mr->inv_wr; + wr->opcode = IB_WR_LOCAL_INV; + smbdirect_mr->cqe.done = local_inv_done; + wr->wr_cqe = &smbdirect_mr->cqe; + wr->num_sge = 0; + wr->ex.invalidate_rkey = smbdirect_mr->mr->rkey; + wr->send_flags = IB_SEND_SIGNALED; + + init_completion(&smbdirect_mr->invalidate_done); + rc = ib_post_send(info->id->qp, wr, NULL); + if (rc) { + log_rdma_mr(ERR, "ib_post_send failed rc=%x\n", rc); + smbd_disconnect_rdma_connection(info); + goto done; + } + wait_for_completion(&smbdirect_mr->invalidate_done); + smbdirect_mr->need_invalidate = false; + } else + /* + * For remote invalidation, just set it to MR_INVALIDATED + * and defer to mr_recovery_work to recover the MR for next use + */ + smbdirect_mr->state = MR_INVALIDATED; + + if (smbdirect_mr->state == MR_INVALIDATED) { + ib_dma_unmap_sg( + info->id->device, smbdirect_mr->sgl, + smbdirect_mr->sgl_count, + smbdirect_mr->dir); + smbdirect_mr->state = MR_READY; + 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; +} |