fs/cifs/smbdirect.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *   Copyright (C) 2017, Microsoft Corporation.
   4  *
   5  *   Author(s): Long Li <longli@microsoft.com>
   6  */
   7 #include <linux/module.h>
   8 #include <linux/highmem.h>
   9 #include "smbdirect.h"
  10 #include "cifs_debug.h"
  11 #include "cifsproto.h"
  12 #include "smb2proto.h"
  13
  14 static struct smbd_response *get_empty_queue_buffer(
  15                 struct smbd_connection *info);
  16 static struct smbd_response *get_receive_buffer(
  17                 struct smbd_connection *info);
  18 static void put_receive_buffer(
  19                 struct smbd_connection *info,
  20                 struct smbd_response *response);
  21 static int allocate_receive_buffers(struct smbd_connection *info, int num_buf);
  22 static void destroy_receive_buffers(struct smbd_connection *info);
  23
  24 static void put_empty_packet(
  25                 struct smbd_connection *info, struct smbd_response *response);
  26 static void enqueue_reassembly(
  27                 struct smbd_connection *info,
  28                 struct smbd_response *response, int data_length);
  29 static struct smbd_response *_get_first_reassembly(
  30                 struct smbd_connection *info);
  31
  32 static int smbd_post_recv(
  33                 struct smbd_connection *info,
  34                 struct smbd_response *response);
  35
  36 static int smbd_post_send_empty(struct smbd_connection *info);
  37 static int smbd_post_send_data(
  38                 struct smbd_connection *info,
  39                 struct kvec *iov, int n_vec, int remaining_data_length);
  40 static int smbd_post_send_page(struct smbd_connection *info,
  41                 struct page *page, unsigned long offset,
  42                 size_t size, int remaining_data_length);
  43
  44 static void destroy_mr_list(struct smbd_connection *info);
  45 static int allocate_mr_list(struct smbd_connection *info);
  46
  47 /* SMBD version number */
  48 #define SMBD_V1 0x0100
  49
  50 /* Port numbers for SMBD transport */
  51 #define SMB_PORT        445
  52 #define SMBD_PORT       5445
  53
  54 /* Address lookup and resolve timeout in ms */
  55 #define RDMA_RESOLVE_TIMEOUT    5000
  56
  57 /* SMBD negotiation timeout in seconds */
  58 #define SMBD_NEGOTIATE_TIMEOUT  120
  59
  60 /* SMBD minimum receive size and fragmented sized defined in [MS-SMBD] */
  61 #define SMBD_MIN_RECEIVE_SIZE           128
  62 #define SMBD_MIN_FRAGMENTED_SIZE        131072
  63
  64 /*
  65  * Default maximum number of RDMA read/write outstanding on this connection
  66  * This value is possibly decreased during QP creation on hardware limit
  67  */
  68 #define SMBD_CM_RESPONDER_RESOURCES     32
  69
  70 /* Maximum number of retries on data transfer operations */
  71 #define SMBD_CM_RETRY                   6
  72 /* No need to retry on Receiver Not Ready since SMBD manages credits */
  73 #define SMBD_CM_RNR_RETRY               0
  74
  75 /*
  76  * User configurable initial values per SMBD transport connection
  77  * as defined in [MS-SMBD] 3.1.1.1
  78  * Those may change after a SMBD negotiation
  79  */
  80 /* The local peer's maximum number of credits to grant to the peer */
  81 int smbd_receive_credit_max = 255;
  82
  83 /* The remote peer's credit request of local peer */
  84 int smbd_send_credit_target = 255;
  85
  86 /* The maximum single message size can be sent to remote peer */
  87 int smbd_max_send_size = 1364;
  88
  89 /*  The maximum fragmented upper-layer payload receive size supported */
  90 int smbd_max_fragmented_recv_size = 1024 * 1024;
  91
  92 /*  The maximum single-message size which can be received */
  93 int smbd_max_receive_size = 8192;
  94
  95 /* The timeout to initiate send of a keepalive message on idle */
  96 int smbd_keep_alive_interval = 120;
  97
  98 /*
  99  * User configurable initial values for RDMA transport
 100  * The actual values used may be lower and are limited to hardware capabilities
 101  */
 102 /* Default maximum number of SGEs in a RDMA write/read */
 103 int smbd_max_frmr_depth = 2048;
 104
 105 /* If payload is less than this byte, use RDMA send/recv not read/write */
 106 int rdma_readwrite_threshold = 4096;
 107
 108 /* Transport logging functions
 109  * Logging are defined as classes. They can be OR'ed to define the actual
 110  * logging level via module parameter smbd_logging_class
 111  * e.g. cifs.smbd_logging_class=0xa0 will log all log_rdma_recv() and
 112  * log_rdma_event()
 113  */
 114 #define LOG_OUTGOING                    0x1
 115 #define LOG_INCOMING                    0x2
 116 #define LOG_READ                        0x4
 117 #define LOG_WRITE                       0x8
 118 #define LOG_RDMA_SEND                   0x10
 119 #define LOG_RDMA_RECV                   0x20
 120 #define LOG_KEEP_ALIVE                  0x40
 121 #define LOG_RDMA_EVENT                  0x80
 122 #define LOG_RDMA_MR                     0x100
 123 static unsigned int smbd_logging_class;
 124 module_param(smbd_logging_class, uint, 0644);
 125 MODULE_PARM_DESC(smbd_logging_class,
 126         "Logging class for SMBD transport 0x0 to 0x100");
 127
 128 #define ERR             0x0
 129 #define INFO            0x1
 130 static unsigned int smbd_logging_level = ERR;
 131 module_param(smbd_logging_level, uint, 0644);
 132 MODULE_PARM_DESC(smbd_logging_level,
 133         "Logging level for SMBD transport, 0 (default): error, 1: info");
 134
 135 #define log_rdma(level, class, fmt, args...)                            \
 136 do {                                                                    \
 137         if (level <= smbd_logging_level || class & smbd_logging_class)  \
 138                 cifs_dbg(VFS, "%s:%d " fmt, __func__, __LINE__, ##args);\
 139 } while (0)
 140
 141 #define log_outgoing(level, fmt, args...) \
 142                 log_rdma(level, LOG_OUTGOING, fmt, ##args)
 143 #define log_incoming(level, fmt, args...) \
 144                 log_rdma(level, LOG_INCOMING, fmt, ##args)
 145 #define log_read(level, fmt, args...)   log_rdma(level, LOG_READ, fmt, ##args)
 146 #define log_write(level, fmt, args...)  log_rdma(level, LOG_WRITE, fmt, ##args)
 147 #define log_rdma_send(level, fmt, args...) \
 148                 log_rdma(level, LOG_RDMA_SEND, fmt, ##args)
 149 #define log_rdma_recv(level, fmt, args...) \
 150                 log_rdma(level, LOG_RDMA_RECV, fmt, ##args)
 151 #define log_keep_alive(level, fmt, args...) \
 152                 log_rdma(level, LOG_KEEP_ALIVE, fmt, ##args)
 153 #define log_rdma_event(level, fmt, args...) \
 154                 log_rdma(level, LOG_RDMA_EVENT, fmt, ##args)
 155 #define log_rdma_mr(level, fmt, args...) \
 156                 log_rdma(level, LOG_RDMA_MR, fmt, ##args)
 157
 158 static void smbd_disconnect_rdma_work(struct work_struct *work)
 159 {
 160         struct smbd_connection *info =
 161                 container_of(work, struct smbd_connection, disconnect_work);
 162
 163         if (info->transport_status == SMBD_CONNECTED) {
 164                 info->transport_status = SMBD_DISCONNECTING;
 165                 rdma_disconnect(info->id);
 166         }
 167 }
 168
 169 static void smbd_disconnect_rdma_connection(struct smbd_connection *info)
 170 {
 171         queue_work(info->workqueue, &info->disconnect_work);
 172 }
 173
 174 /* Upcall from RDMA CM */
 175 static int smbd_conn_upcall(
 176                 struct rdma_cm_id *id, struct rdma_cm_event *event)
 177 {
 178         struct smbd_connection *info = id->context;
 179
 180         log_rdma_event(INFO, "event=%d status=%d\n",
 181                 event->event, event->status);
 182
 183         switch (event->event) {
 184         case RDMA_CM_EVENT_ADDR_RESOLVED:
 185         case RDMA_CM_EVENT_ROUTE_RESOLVED:
 186                 info->ri_rc = 0;
 187                 complete(&info->ri_done);
 188                 break;
 189
 190         case RDMA_CM_EVENT_ADDR_ERROR:
 191                 info->ri_rc = -EHOSTUNREACH;
 192                 complete(&info->ri_done);
 193                 break;
 194
 195         case RDMA_CM_EVENT_ROUTE_ERROR:
 196                 info->ri_rc = -ENETUNREACH;
 197                 complete(&info->ri_done);
 198                 break;
 199
 200         case RDMA_CM_EVENT_ESTABLISHED:
 201                 log_rdma_event(INFO, "connected event=%d\n", event->event);
 202                 info->transport_status = SMBD_CONNECTED;
 203                 wake_up_interruptible(&info->conn_wait);
 204                 break;
 205
 206         case RDMA_CM_EVENT_CONNECT_ERROR:
 207         case RDMA_CM_EVENT_UNREACHABLE:
 208         case RDMA_CM_EVENT_REJECTED:
 209                 log_rdma_event(INFO, "connecting failed event=%d\n", event->event);
 210                 info->transport_status = SMBD_DISCONNECTED;
 211                 wake_up_interruptible(&info->conn_wait);
 212                 break;
 213
 214         case RDMA_CM_EVENT_DEVICE_REMOVAL:
 215         case RDMA_CM_EVENT_DISCONNECTED:
 216                 /* This happenes when we fail the negotiation */
 217                 if (info->transport_status == SMBD_NEGOTIATE_FAILED) {
 218                         info->transport_status = SMBD_DISCONNECTED;
 219                         wake_up(&info->conn_wait);
 220                         break;
 221                 }
 222
 223                 info->transport_status = SMBD_DISCONNECTED;
 224                 wake_up_interruptible(&info->disconn_wait);
 225                 wake_up_interruptible(&info->wait_reassembly_queue);
 226                 wake_up_interruptible_all(&info->wait_send_queue);
 227                 break;
 228
 229         default:
 230                 break;
 231         }
 232
 233         return 0;
 234 }
 235
 236 /* Upcall from RDMA QP */
 237 static void
 238 smbd_qp_async_error_upcall(struct ib_event *event, void *context)
 239 {
 240         struct smbd_connection *info = context;
 241
 242         log_rdma_event(ERR, "%s on device %s info %p\n",
 243                 ib_event_msg(event->event), event->device->name, info);
 244
 245         switch (event->event) {
 246         case IB_EVENT_CQ_ERR:
 247         case IB_EVENT_QP_FATAL:
 248                 smbd_disconnect_rdma_connection(info);
 249
 250         default:
 251                 break;
 252         }
 253 }
 254
 255 static inline void *smbd_request_payload(struct smbd_request *request)
 256 {
 257         return (void *)request->packet;
 258 }
 259
 260 static inline void *smbd_response_payload(struct smbd_response *response)
 261 {
 262         return (void *)response->packet;
 263 }
 264
 265 /* Called when a RDMA send is done */
 266 static void send_done(struct ib_cq *cq, struct ib_wc *wc)
 267 {
 268         int i;
 269         struct smbd_request *request =
 270                 container_of(wc->wr_cqe, struct smbd_request, cqe);
 271
 272         log_rdma_send(INFO, "smbd_request %p completed wc->status=%d\n",
 273                 request, wc->status);
 274
 275         if (wc->status != IB_WC_SUCCESS || wc->opcode != IB_WC_SEND) {
 276                 log_rdma_send(ERR, "wc->status=%d wc->opcode=%d\n",
 277                         wc->status, wc->opcode);
 278                 smbd_disconnect_rdma_connection(request->info);
 279         }
 280
 281         for (i = 0; i < request->num_sge; i++)
 282                 ib_dma_unmap_single(request->info->id->device,
 283                         request->sge[i].addr,
 284                         request->sge[i].length,
 285                         DMA_TO_DEVICE);
 286
 287         if (atomic_dec_and_test(&request->info->send_pending))
 288                 wake_up(&request->info->wait_send_pending);
 289
 290         wake_up(&request->info->wait_post_send);
 291
 292         mempool_free(request, request->info->request_mempool);
 293 }
 294
 295 static void dump_smbd_negotiate_resp(struct smbd_negotiate_resp *resp)
 296 {
 297         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",
 298                        resp->min_version, resp->max_version,
 299                        resp->negotiated_version, resp->credits_requested,
 300                        resp->credits_granted, resp->status,
 301                        resp->max_readwrite_size, resp->preferred_send_size,
 302                        resp->max_receive_size, resp->max_fragmented_size);
 303 }
 304
 305 /*
 306  * Process a negotiation response message, according to [MS-SMBD]3.1.5.7
 307  * response, packet_length: the negotiation response message
 308  * return value: true if negotiation is a success, false if failed
 309  */
 310 static bool process_negotiation_response(
 311                 struct smbd_response *response, int packet_length)
 312 {
 313         struct smbd_connection *info = response->info;
 314         struct smbd_negotiate_resp *packet = smbd_response_payload(response);
 315
 316         if (packet_length < sizeof(struct smbd_negotiate_resp)) {
 317                 log_rdma_event(ERR,
 318                         "error: packet_length=%d\n", packet_length);
 319                 return false;
 320         }
 321
 322         if (le16_to_cpu(packet->negotiated_version) != SMBD_V1) {
 323                 log_rdma_event(ERR, "error: negotiated_version=%x\n",
 324                         le16_to_cpu(packet->negotiated_version));
 325                 return false;
 326         }
 327         info->protocol = le16_to_cpu(packet->negotiated_version);
 328
 329         if (packet->credits_requested == 0) {
 330                 log_rdma_event(ERR, "error: credits_requested==0\n");
 331                 return false;
 332         }
 333         info->receive_credit_target = le16_to_cpu(packet->credits_requested);
 334
 335         if (packet->credits_granted == 0) {
 336                 log_rdma_event(ERR, "error: credits_granted==0\n");
 337                 return false;
 338         }
 339         atomic_set(&info->send_credits, le16_to_cpu(packet->credits_granted));
 340
 341         atomic_set(&info->receive_credits, 0);
 342
 343         if (le32_to_cpu(packet->preferred_send_size) > info->max_receive_size) {
 344                 log_rdma_event(ERR, "error: preferred_send_size=%d\n",
 345                         le32_to_cpu(packet->preferred_send_size));
 346                 return false;
 347         }
 348         info->max_receive_size = le32_to_cpu(packet->preferred_send_size);
 349
 350         if (le32_to_cpu(packet->max_receive_size) < SMBD_MIN_RECEIVE_SIZE) {
 351                 log_rdma_event(ERR, "error: max_receive_size=%d\n",
 352                         le32_to_cpu(packet->max_receive_size));
 353                 return false;
 354         }
 355         info->max_send_size = min_t(int, info->max_send_size,
 356                                         le32_to_cpu(packet->max_receive_size));
 357
 358         if (le32_to_cpu(packet->max_fragmented_size) <
 359                         SMBD_MIN_FRAGMENTED_SIZE) {
 360                 log_rdma_event(ERR, "error: max_fragmented_size=%d\n",
 361                         le32_to_cpu(packet->max_fragmented_size));
 362                 return false;
 363         }
 364         info->max_fragmented_send_size =
 365                 le32_to_cpu(packet->max_fragmented_size);
 366         info->rdma_readwrite_threshold =
 367                 rdma_readwrite_threshold > info->max_fragmented_send_size ?
 368                 info->max_fragmented_send_size :
 369                 rdma_readwrite_threshold;
 370
 371
 372         info->max_readwrite_size = min_t(u32,
 373                         le32_to_cpu(packet->max_readwrite_size),
 374                         info->max_frmr_depth * PAGE_SIZE);
 375         info->max_frmr_depth = info->max_readwrite_size / PAGE_SIZE;
 376
 377         return true;
 378 }
 379
 380 static void smbd_post_send_credits(struct work_struct *work)
 381 {
 382         int ret = 0;
 383         int use_receive_queue = 1;
 384         int rc;
 385         struct smbd_response *response;
 386         struct smbd_connection *info =
 387                 container_of(work, struct smbd_connection,
 388                         post_send_credits_work);
 389
 390         if (info->transport_status != SMBD_CONNECTED) {
 391                 wake_up(&info->wait_receive_queues);
 392                 return;
 393         }
 394
 395         if (info->receive_credit_target >
 396                 atomic_read(&info->receive_credits)) {
 397                 while (true) {
 398                         if (use_receive_queue)
 399                                 response = get_receive_buffer(info);
 400                         else
 401                                 response = get_empty_queue_buffer(info);
 402                         if (!response) {
 403                                 /* now switch to emtpy packet queue */
 404                                 if (use_receive_queue) {
 405                                         use_receive_queue = 0;
 406                                         continue;
 407                                 } else
 408                                         break;
 409                         }
 410
 411                         response->type = SMBD_TRANSFER_DATA;
 412                         response->first_segment = false;
 413                         rc = smbd_post_recv(info, response);
 414                         if (rc) {
 415                                 log_rdma_recv(ERR,
 416                                         "post_recv failed rc=%d\n", rc);
 417                                 put_receive_buffer(info, response);
 418                                 break;
 419                         }
 420
 421                         ret++;
 422                 }
 423         }
 424
 425         spin_lock(&info->lock_new_credits_offered);
 426         info->new_credits_offered += ret;
 427         spin_unlock(&info->lock_new_credits_offered);
 428
 429         /* Promptly send an immediate packet as defined in [MS-SMBD] 3.1.1.1 */
 430         info->send_immediate = true;
 431         if (atomic_read(&info->receive_credits) <
 432                 info->receive_credit_target - 1) {
 433                 if (info->keep_alive_requested == KEEP_ALIVE_PENDING ||
 434                     info->send_immediate) {
 435                         log_keep_alive(INFO, "send an empty message\n");
 436                         smbd_post_send_empty(info);
 437                 }
 438         }
 439 }
 440
 441 /* Called from softirq, when recv is done */
 442 static void recv_done(struct ib_cq *cq, struct ib_wc *wc)
 443 {
 444         struct smbd_data_transfer *data_transfer;
 445         struct smbd_response *response =
 446                 container_of(wc->wr_cqe, struct smbd_response, cqe);
 447         struct smbd_connection *info = response->info;
 448         int data_length = 0;
 449
 450         log_rdma_recv(INFO, "response=%p type=%d wc status=%d wc opcode %d byte_len=%d pkey_index=%x\n",
 451                       response, response->type, wc->status, wc->opcode,
 452                       wc->byte_len, wc->pkey_index);
 453
 454         if (wc->status != IB_WC_SUCCESS || wc->opcode != IB_WC_RECV) {
 455                 log_rdma_recv(INFO, "wc->status=%d opcode=%d\n",
 456                         wc->status, wc->opcode);
 457                 smbd_disconnect_rdma_connection(info);
 458                 goto error;
 459         }
 460
 461         ib_dma_sync_single_for_cpu(
 462                 wc->qp->device,
 463                 response->sge.addr,
 464                 response->sge.length,
 465                 DMA_FROM_DEVICE);
 466
 467         switch (response->type) {
 468         /* SMBD negotiation response */
 469         case SMBD_NEGOTIATE_RESP:
 470                 dump_smbd_negotiate_resp(smbd_response_payload(response));
 471                 info->full_packet_received = true;
 472                 info->negotiate_done =
 473                         process_negotiation_response(response, wc->byte_len);
 474                 complete(&info->negotiate_completion);
 475                 break;
 476
 477         /* SMBD data transfer packet */
 478         case SMBD_TRANSFER_DATA:
 479                 data_transfer = smbd_response_payload(response);
 480                 data_length = le32_to_cpu(data_transfer->data_length);
 481
 482                 /*
 483                  * If this is a packet with data playload place the data in
 484                  * reassembly queue and wake up the reading thread
 485                  */
 486                 if (data_length) {
 487                         if (info->full_packet_received)
 488                                 response->first_segment = true;
 489
 490                         if (le32_to_cpu(data_transfer->remaining_data_length))
 491                                 info->full_packet_received = false;
 492                         else
 493                                 info->full_packet_received = true;
 494
 495                         enqueue_reassembly(
 496                                 info,
 497                                 response,
 498                                 data_length);
 499                 } else
 500                         put_empty_packet(info, response);
 501
 502                 if (data_length)
 503                         wake_up_interruptible(&info->wait_reassembly_queue);
 504
 505                 atomic_dec(&info->receive_credits);
 506                 info->receive_credit_target =
 507                         le16_to_cpu(data_transfer->credits_requested);
 508                 if (le16_to_cpu(data_transfer->credits_granted)) {
 509                         atomic_add(le16_to_cpu(data_transfer->credits_granted),
 510                                 &info->send_credits);
 511                         /*
 512                          * We have new send credits granted from remote peer
 513                          * If any sender is waiting for credits, unblock it
 514                          */
 515                         wake_up_interruptible(&info->wait_send_queue);
 516                 }
 517
 518                 log_incoming(INFO, "data flags %d data_offset %d data_length %d remaining_data_length %d\n",
 519                              le16_to_cpu(data_transfer->flags),
 520                              le32_to_cpu(data_transfer->data_offset),
 521                              le32_to_cpu(data_transfer->data_length),
 522                              le32_to_cpu(data_transfer->remaining_data_length));
 523
 524                 /* Send a KEEP_ALIVE response right away if requested */
 525                 info->keep_alive_requested = KEEP_ALIVE_NONE;
 526                 if (le16_to_cpu(data_transfer->flags) &
 527                                 SMB_DIRECT_RESPONSE_REQUESTED) {
 528                         info->keep_alive_requested = KEEP_ALIVE_PENDING;
 529                 }
 530
 531                 return;
 532
 533         default:
 534                 log_rdma_recv(ERR,
 535                         "unexpected response type=%d\n", response->type);
 536         }
 537
 538 error:
 539         put_receive_buffer(info, response);
 540 }
 541
 542 static struct rdma_cm_id *smbd_create_id(
 543                 struct smbd_connection *info,
 544                 struct sockaddr *dstaddr, int port)
 545 {
 546         struct rdma_cm_id *id;
 547         int rc;
 548         __be16 *sport;
 549
 550         id = rdma_create_id(&init_net, smbd_conn_upcall, info,
 551                 RDMA_PS_TCP, IB_QPT_RC);
 552         if (IS_ERR(id)) {
 553                 rc = PTR_ERR(id);
 554                 log_rdma_event(ERR, "rdma_create_id() failed %i\n", rc);
 555                 return id;
 556         }
 557
 558         if (dstaddr->sa_family == AF_INET6)
 559                 sport = &((struct sockaddr_in6 *)dstaddr)->sin6_port;
 560         else
 561                 sport = &((struct sockaddr_in *)dstaddr)->sin_port;
 562
 563         *sport = htons(port);
 564
 565         init_completion(&info->ri_done);
 566         info->ri_rc = -ETIMEDOUT;
 567
 568         rc = rdma_resolve_addr(id, NULL, (struct sockaddr *)dstaddr,
 569                 RDMA_RESOLVE_TIMEOUT);
 570         if (rc) {
 571                 log_rdma_event(ERR, "rdma_resolve_addr() failed %i\n", rc);
 572                 goto out;
 573         }
 574         rc = wait_for_completion_interruptible_timeout(
 575                 &info->ri_done, msecs_to_jiffies(RDMA_RESOLVE_TIMEOUT));
 576         /* e.g. if interrupted returns -ERESTARTSYS */
 577         if (rc < 0) {
 578                 log_rdma_event(ERR, "rdma_resolve_addr timeout rc: %i\n", rc);
 579                 goto out;
 580         }
 581         rc = info->ri_rc;
 582         if (rc) {
 583                 log_rdma_event(ERR, "rdma_resolve_addr() completed %i\n", rc);
 584                 goto out;
 585         }
 586
 587         info->ri_rc = -ETIMEDOUT;
 588         rc = rdma_resolve_route(id, RDMA_RESOLVE_TIMEOUT);
 589         if (rc) {
 590                 log_rdma_event(ERR, "rdma_resolve_route() failed %i\n", rc);
 591                 goto out;
 592         }
 593         rc = wait_for_completion_interruptible_timeout(
 594                 &info->ri_done, msecs_to_jiffies(RDMA_RESOLVE_TIMEOUT));
 595         /* e.g. if interrupted returns -ERESTARTSYS */
 596         if (rc < 0)  {
 597                 log_rdma_event(ERR, "rdma_resolve_addr timeout rc: %i\n", rc);
 598                 goto out;
 599         }
 600         rc = info->ri_rc;
 601         if (rc) {
 602                 log_rdma_event(ERR, "rdma_resolve_route() completed %i\n", rc);
 603                 goto out;
 604         }
 605
 606         return id;
 607
 608 out:
 609         rdma_destroy_id(id);
 610         return ERR_PTR(rc);
 611 }
 612
 613 /*
 614  * Test if FRWR (Fast Registration Work Requests) is supported on the device
 615  * This implementation requries FRWR on RDMA read/write
 616  * return value: true if it is supported
 617  */
 618 static bool frwr_is_supported(struct ib_device_attr *attrs)
 619 {
 620         if (!(attrs->device_cap_flags & IB_DEVICE_MEM_MGT_EXTENSIONS))
 621                 return false;
 622         if (attrs->max_fast_reg_page_list_len == 0)
 623                 return false;
 624         return true;
 625 }
 626
 627 static int smbd_ia_open(
 628                 struct smbd_connection *info,
 629                 struct sockaddr *dstaddr, int port)
 630 {
 631         int rc;
 632
 633         info->id = smbd_create_id(info, dstaddr, port);
 634         if (IS_ERR(info->id)) {
 635                 rc = PTR_ERR(info->id);
 636                 goto out1;
 637         }
 638
 639         if (!frwr_is_supported(&info->id->device->attrs)) {
 640                 log_rdma_event(ERR, "Fast Registration Work Requests (FRWR) is not supported\n");
 641                 log_rdma_event(ERR, "Device capability flags = %llx max_fast_reg_page_list_len = %u\n",
 642                                info->id->device->attrs.device_cap_flags,
 643                                info->id->device->attrs.max_fast_reg_page_list_len);
 644                 rc = -EPROTONOSUPPORT;
 645                 goto out2;
 646         }
 647         info->max_frmr_depth = min_t(int,
 648                 smbd_max_frmr_depth,
 649                 info->id->device->attrs.max_fast_reg_page_list_len);
 650         info->mr_type = IB_MR_TYPE_MEM_REG;
 651         if (info->id->device->attrs.device_cap_flags & IB_DEVICE_SG_GAPS_REG)
 652                 info->mr_type = IB_MR_TYPE_SG_GAPS;
 653
 654         info->pd = ib_alloc_pd(info->id->device, 0);
 655         if (IS_ERR(info->pd)) {
 656                 rc = PTR_ERR(info->pd);
 657                 log_rdma_event(ERR, "ib_alloc_pd() returned %d\n", rc);
 658                 goto out2;
 659         }
 660
 661         return 0;
 662
 663 out2:
 664         rdma_destroy_id(info->id);
 665         info->id = NULL;
 666
 667 out1:
 668         return rc;
 669 }
 670
 671 /*
 672  * Send a negotiation request message to the peer
 673  * The negotiation procedure is in [MS-SMBD] 3.1.5.2 and 3.1.5.3
 674  * After negotiation, the transport is connected and ready for
 675  * carrying upper layer SMB payload
 676  */
 677 static int smbd_post_send_negotiate_req(struct smbd_connection *info)
 678 {
 679         struct ib_send_wr send_wr;
 680         int rc = -ENOMEM;
 681         struct smbd_request *request;
 682         struct smbd_negotiate_req *packet;
 683
 684         request = mempool_alloc(info->request_mempool, GFP_KERNEL);
 685         if (!request)
 686                 return rc;
 687
 688         request->info = info;
 689
 690         packet = smbd_request_payload(request);
 691         packet->min_version = cpu_to_le16(SMBD_V1);
 692         packet->max_version = cpu_to_le16(SMBD_V1);
 693         packet->reserved = 0;
 694         packet->credits_requested = cpu_to_le16(info->send_credit_target);
 695         packet->preferred_send_size = cpu_to_le32(info->max_send_size);
 696         packet->max_receive_size = cpu_to_le32(info->max_receive_size);
 697         packet->max_fragmented_size =
 698                 cpu_to_le32(info->max_fragmented_recv_size);
 699
 700         request->num_sge = 1;
 701         request->sge[0].addr = ib_dma_map_single(
 702                                 info->id->device, (void *)packet,
 703                                 sizeof(*packet), DMA_TO_DEVICE);
 704         if (ib_dma_mapping_error(info->id->device, request->sge[0].addr)) {
 705                 rc = -EIO;
 706                 goto dma_mapping_failed;
 707         }
 708
 709         request->sge[0].length = sizeof(*packet);
 710         request->sge[0].lkey = info->pd->local_dma_lkey;
 711
 712         ib_dma_sync_single_for_device(
 713                 info->id->device, request->sge[0].addr,
 714                 request->sge[0].length, DMA_TO_DEVICE);
 715
 716         request->cqe.done = send_done;
 717
 718         send_wr.next = NULL;
 719         send_wr.wr_cqe = &request->cqe;
 720         send_wr.sg_list = request->sge;
 721         send_wr.num_sge = request->num_sge;
 722         send_wr.opcode = IB_WR_SEND;
 723         send_wr.send_flags = IB_SEND_SIGNALED;
 724
 725         log_rdma_send(INFO, "sge addr=%llx length=%x lkey=%x\n",
 726                 request->sge[0].addr,
 727                 request->sge[0].length, request->sge[0].lkey);
 728
 729         atomic_inc(&info->send_pending);
 730         rc = ib_post_send(info->id->qp, &send_wr, NULL);
 731         if (!rc)
 732                 return 0;
 733
 734         /* if we reach here, post send failed */
 735         log_rdma_send(ERR, "ib_post_send failed rc=%d\n", rc);
 736         atomic_dec(&info->send_pending);
 737         ib_dma_unmap_single(info->id->device, request->sge[0].addr,
 738                 request->sge[0].length, DMA_TO_DEVICE);
 739
 740         smbd_disconnect_rdma_connection(info);
 741
 742 dma_mapping_failed:
 743         mempool_free(request, info->request_mempool);
 744         return rc;
 745 }
 746
 747 /*
 748  * Extend the credits to remote peer
 749  * This implements [MS-SMBD] 3.1.5.9
 750  * The idea is that we should extend credits to remote peer as quickly as
 751  * it's allowed, to maintain data flow. We allocate as much receive
 752  * buffer as possible, and extend the receive credits to remote peer
 753  * return value: the new credtis being granted.
 754  */
 755 static int manage_credits_prior_sending(struct smbd_connection *info)
 756 {
 757         int new_credits;
 758
 759         spin_lock(&info->lock_new_credits_offered);
 760         new_credits = info->new_credits_offered;
 761         info->new_credits_offered = 0;
 762         spin_unlock(&info->lock_new_credits_offered);
 763
 764         return new_credits;
 765 }
 766
 767 /*
 768  * Check if we need to send a KEEP_ALIVE message
 769  * The idle connection timer triggers a KEEP_ALIVE message when expires
 770  * SMB_DIRECT_RESPONSE_REQUESTED is set in the message flag to have peer send
 771  * back a response.
 772  * return value:
 773  * 1 if SMB_DIRECT_RESPONSE_REQUESTED needs to be set
 774  * 0: otherwise
 775  */
 776 static int manage_keep_alive_before_sending(struct smbd_connection *info)
 777 {
 778         if (info->keep_alive_requested == KEEP_ALIVE_PENDING) {
 779                 info->keep_alive_requested = KEEP_ALIVE_SENT;
 780                 return 1;
 781         }
 782         return 0;
 783 }
 784
 785 /* Post the send request */
 786 static int smbd_post_send(struct smbd_connection *info,
 787                 struct smbd_request *request)
 788 {
 789         struct ib_send_wr send_wr;
 790         int rc, i;
 791
 792         for (i = 0; i < request->num_sge; i++) {
 793                 log_rdma_send(INFO,
 794                         "rdma_request sge[%d] addr=%llu length=%u\n",
 795                         i, request->sge[i].addr, request->sge[i].length);
 796                 ib_dma_sync_single_for_device(
 797                         info->id->device,
 798                         request->sge[i].addr,
 799                         request->sge[i].length,
 800                         DMA_TO_DEVICE);
 801         }
 802
 803         request->cqe.done = send_done;
 804
 805         send_wr.next = NULL;
 806         send_wr.wr_cqe = &request->cqe;
 807         send_wr.sg_list = request->sge;
 808         send_wr.num_sge = request->num_sge;
 809         send_wr.opcode = IB_WR_SEND;
 810         send_wr.send_flags = IB_SEND_SIGNALED;
 811
 812         rc = ib_post_send(info->id->qp, &send_wr, NULL);
 813         if (rc) {
 814                 log_rdma_send(ERR, "ib_post_send failed rc=%d\n", rc);
 815                 smbd_disconnect_rdma_connection(info);
 816                 rc = -EAGAIN;
 817         } else
 818                 /* Reset timer for idle connection after packet is sent */
 819                 mod_delayed_work(info->workqueue, &info->idle_timer_work,
 820                         info->keep_alive_interval*HZ);
 821
 822         return rc;
 823 }
 824
 825 static int smbd_post_send_sgl(struct smbd_connection *info,
 826         struct scatterlist *sgl, int data_length, int remaining_data_length)
 827 {
 828         int num_sgs;
 829         int i, rc;
 830         int header_length;
 831         struct smbd_request *request;
 832         struct smbd_data_transfer *packet;
 833         int new_credits;
 834         struct scatterlist *sg;
 835
 836 wait_credit:
 837         /* Wait for send credits. A SMBD packet needs one credit */
 838         rc = wait_event_interruptible(info->wait_send_queue,
 839                 atomic_read(&info->send_credits) > 0 ||
 840                 info->transport_status != SMBD_CONNECTED);
 841         if (rc)
 842                 goto err_wait_credit;
 843
 844         if (info->transport_status != SMBD_CONNECTED) {
 845                 log_outgoing(ERR, "disconnected not sending on wait_credit\n");
 846                 rc = -EAGAIN;
 847                 goto err_wait_credit;
 848         }
 849         if (unlikely(atomic_dec_return(&info->send_credits) < 0)) {
 850                 atomic_inc(&info->send_credits);
 851                 goto wait_credit;
 852         }
 853
 854 wait_send_queue:
 855         wait_event(info->wait_post_send,
 856                 atomic_read(&info->send_pending) < info->send_credit_target ||
 857                 info->transport_status != SMBD_CONNECTED);
 858
 859         if (info->transport_status != SMBD_CONNECTED) {
 860                 log_outgoing(ERR, "disconnected not sending on wait_send_queue\n");
 861                 rc = -EAGAIN;
 862                 goto err_wait_send_queue;
 863         }
 864
 865         if (unlikely(atomic_inc_return(&info->send_pending) >
 866                                 info->send_credit_target)) {
 867                 atomic_dec(&info->send_pending);
 868                 goto wait_send_queue;
 869         }
 870
 871         request = mempool_alloc(info->request_mempool, GFP_KERNEL);
 872         if (!request) {
 873                 rc = -ENOMEM;
 874                 goto err_alloc;
 875         }
 876
 877         request->info = info;
 878
 879         /* Fill in the packet header */
 880         packet = smbd_request_payload(request);
 881         packet->credits_requested = cpu_to_le16(info->send_credit_target);
 882
 883         new_credits = manage_credits_prior_sending(info);
 884         atomic_add(new_credits, &info->receive_credits);
 885         packet->credits_granted = cpu_to_le16(new_credits);
 886
 887         info->send_immediate = false;
 888
 889         packet->flags = 0;
 890         if (manage_keep_alive_before_sending(info))
 891                 packet->flags |= cpu_to_le16(SMB_DIRECT_RESPONSE_REQUESTED);
 892
 893         packet->reserved = 0;
 894         if (!data_length)
 895                 packet->data_offset = 0;
 896         else
 897                 packet->data_offset = cpu_to_le32(24);
 898         packet->data_length = cpu_to_le32(data_length);
 899         packet->remaining_data_length = cpu_to_le32(remaining_data_length);
 900         packet->padding = 0;
 901
 902         log_outgoing(INFO, "credits_requested=%d credits_granted=%d data_offset=%d data_length=%d remaining_data_length=%d\n",
 903                      le16_to_cpu(packet->credits_requested),
 904                      le16_to_cpu(packet->credits_granted),
 905                      le32_to_cpu(packet->data_offset),
 906                      le32_to_cpu(packet->data_length),
 907                      le32_to_cpu(packet->remaining_data_length));
 908
 909         /* Map the packet to DMA */
 910         header_length = sizeof(struct smbd_data_transfer);
 911         /* If this is a packet without payload, don't send padding */
 912         if (!data_length)
 913                 header_length = offsetof(struct smbd_data_transfer, padding);
 914
 915         request->num_sge = 1;
 916         request->sge[0].addr = ib_dma_map_single(info->id->device,
 917                                                  (void *)packet,
 918                                                  header_length,
 919                                                  DMA_TO_DEVICE);
 920         if (ib_dma_mapping_error(info->id->device, request->sge[0].addr)) {
 921                 rc = -EIO;
 922                 request->sge[0].addr = 0;
 923                 goto err_dma;
 924         }
 925
 926         request->sge[0].length = header_length;
 927         request->sge[0].lkey = info->pd->local_dma_lkey;
 928
 929         /* Fill in the packet data payload */
 930         num_sgs = sgl ? sg_nents(sgl) : 0;
 931         for_each_sg(sgl, sg, num_sgs, i) {
 932                 request->sge[i+1].addr =
 933                         ib_dma_map_page(info->id->device, sg_page(sg),
 934                                sg->offset, sg->length, DMA_TO_DEVICE);
 935                 if (ib_dma_mapping_error(
 936                                 info->id->device, request->sge[i+1].addr)) {
 937                         rc = -EIO;
 938                         request->sge[i+1].addr = 0;
 939                         goto err_dma;
 940                 }
 941                 request->sge[i+1].length = sg->length;
 942                 request->sge[i+1].lkey = info->pd->local_dma_lkey;
 943                 request->num_sge++;
 944         }
 945
 946         rc = smbd_post_send(info, request);
 947         if (!rc)
 948                 return 0;
 949
 950 err_dma:
 951         for (i = 0; i < request->num_sge; i++)
 952                 if (request->sge[i].addr)
 953                         ib_dma_unmap_single(info->id->device,
 954                                             request->sge[i].addr,
 955                                             request->sge[i].length,
 956                                             DMA_TO_DEVICE);
 957         mempool_free(request, info->request_mempool);
 958
 959         /* roll back receive credits and credits to be offered */
 960         spin_lock(&info->lock_new_credits_offered);
 961         info->new_credits_offered += new_credits;
 962         spin_unlock(&info->lock_new_credits_offered);
 963         atomic_sub(new_credits, &info->receive_credits);
 964
 965 err_alloc:
 966         if (atomic_dec_and_test(&info->send_pending))
 967                 wake_up(&info->wait_send_pending);
 968
 969 err_wait_send_queue:
 970         /* roll back send credits and pending */
 971         atomic_inc(&info->send_credits);
 972
 973 err_wait_credit:
 974         return rc;
 975 }
 976
 977 /*
 978  * Send a page
 979  * page: the page to send
 980  * offset: offset in the page to send
 981  * size: length in the page to send
 982  * remaining_data_length: remaining data to send in this payload
 983  */
 984 static int smbd_post_send_page(struct smbd_connection *info, struct page *page,
 985                 unsigned long offset, size_t size, int remaining_data_length)
 986 {
 987         struct scatterlist sgl;
 988
 989         sg_init_table(&sgl, 1);
 990         sg_set_page(&sgl, page, size, offset);
 991
 992         return smbd_post_send_sgl(info, &sgl, size, remaining_data_length);
 993 }
 994
 995 /*
 996  * Send an empty message
 997  * Empty message is used to extend credits to peer to for keep live
 998  * while there is no upper layer payload to send at the time
 999  */
1000 static int smbd_post_send_empty(struct smbd_connection *info)
1001 {
1002         info->count_send_empty++;
1003         return smbd_post_send_sgl(info, NULL, 0, 0);
1004 }
1005
1006 /*
1007  * Send a data buffer
1008  * iov: the iov array describing the data buffers
1009  * n_vec: number of iov array
1010  * remaining_data_length: remaining data to send following this packet
1011  * in segmented SMBD packet
1012  */
1013 static int smbd_post_send_data(
1014         struct smbd_connection *info, struct kvec *iov, int n_vec,
1015         int remaining_data_length)
1016 {
1017         int i;
1018         u32 data_length = 0;
1019         struct scatterlist sgl[SMBDIRECT_MAX_SGE];
1020
1021         if (n_vec > SMBDIRECT_MAX_SGE) {
1022                 cifs_dbg(VFS, "Can't fit data to SGL, n_vec=%d\n", n_vec);
1023                 return -EINVAL;
1024         }
1025
1026         sg_init_table(sgl, n_vec);
1027         for (i = 0; i < n_vec; i++) {
1028                 data_length += iov[i].iov_len;
1029                 sg_set_buf(&sgl[i], iov[i].iov_base, iov[i].iov_len);
1030         }
1031
1032         return smbd_post_send_sgl(info, sgl, data_length, remaining_data_length);
1033 }
1034
1035 /*
1036  * Post a receive request to the transport
1037  * The remote peer can only send data when a receive request is posted
1038  * The interaction is controlled by send/receive credit system
1039  */
1040 static int smbd_post_recv(
1041                 struct smbd_connection *info, struct smbd_response *response)
1042 {
1043         struct ib_recv_wr recv_wr;
1044         int rc = -EIO;
1045
1046         response->sge.addr = ib_dma_map_single(
1047                                 info->id->device, response->packet,
1048                                 info->max_receive_size, DMA_FROM_DEVICE);
1049         if (ib_dma_mapping_error(info->id->device, response->sge.addr))
1050                 return rc;
1051
1052         response->sge.length = info->max_receive_size;
1053         response->sge.lkey = info->pd->local_dma_lkey;
1054
1055         response->cqe.done = recv_done;
1056
1057         recv_wr.wr_cqe = &response->cqe;
1058         recv_wr.next = NULL;
1059         recv_wr.sg_list = &response->sge;
1060         recv_wr.num_sge = 1;
1061
1062         rc = ib_post_recv(info->id->qp, &recv_wr, NULL);
1063         if (rc) {
1064                 ib_dma_unmap_single(info->id->device, response->sge.addr,
1065                                     response->sge.length, DMA_FROM_DEVICE);
1066                 smbd_disconnect_rdma_connection(info);
1067                 log_rdma_recv(ERR, "ib_post_recv failed rc=%d\n", rc);
1068         }
1069
1070         return rc;
1071 }
1072
1073 /* Perform SMBD negotiate according to [MS-SMBD] 3.1.5.2 */
1074 static int smbd_negotiate(struct smbd_connection *info)
1075 {
1076         int rc;
1077         struct smbd_response *response = get_receive_buffer(info);
1078
1079         response->type = SMBD_NEGOTIATE_RESP;
1080         rc = smbd_post_recv(info, response);
1081         log_rdma_event(INFO, "smbd_post_recv rc=%d iov.addr=%llx iov.length=%x iov.lkey=%x\n",
1082                        rc, response->sge.addr,
1083                        response->sge.length, response->sge.lkey);
1084         if (rc)
1085                 return rc;
1086
1087         init_completion(&info->negotiate_completion);
1088         info->negotiate_done = false;
1089         rc = smbd_post_send_negotiate_req(info);
1090         if (rc)
1091                 return rc;
1092
1093         rc = wait_for_completion_interruptible_timeout(
1094                 &info->negotiate_completion, SMBD_NEGOTIATE_TIMEOUT * HZ);
1095         log_rdma_event(INFO, "wait_for_completion_timeout rc=%d\n", rc);
1096
1097         if (info->negotiate_done)
1098                 return 0;
1099
1100         if (rc == 0)
1101                 rc = -ETIMEDOUT;
1102         else if (rc == -ERESTARTSYS)
1103                 rc = -EINTR;
1104         else
1105                 rc = -ENOTCONN;
1106
1107         return rc;
1108 }
1109
1110 static void put_empty_packet(
1111                 struct smbd_connection *info, struct smbd_response *response)
1112 {
1113         spin_lock(&info->empty_packet_queue_lock);
1114         list_add_tail(&response->list, &info->empty_packet_queue);
1115         info->count_empty_packet_queue++;
1116         spin_unlock(&info->empty_packet_queue_lock);
1117
1118         queue_work(info->workqueue, &info->post_send_credits_work);
1119 }
1120
1121 /*
1122  * Implement Connection.FragmentReassemblyBuffer defined in [MS-SMBD] 3.1.1.1
1123  * This is a queue for reassembling upper layer payload and present to upper
1124  * layer. All the inncoming payload go to the reassembly queue, regardless of
1125  * if reassembly is required. The uuper layer code reads from the queue for all
1126  * incoming payloads.
1127  * Put a received packet to the reassembly queue
1128  * response: the packet received
1129  * data_length: the size of payload in this packet
1130  */
1131 static void enqueue_reassembly(
1132         struct smbd_connection *info,
1133         struct smbd_response *response,
1134         int data_length)
1135 {
1136         spin_lock(&info->reassembly_queue_lock);
1137         list_add_tail(&response->list, &info->reassembly_queue);
1138         info->reassembly_queue_length++;
1139         /*
1140          * Make sure reassembly_data_length is updated after list and
1141          * reassembly_queue_length are updated. On the dequeue side
1142          * reassembly_data_length is checked without a lock to determine
1143          * if reassembly_queue_length and list is up to date
1144          */
1145         virt_wmb();
1146         info->reassembly_data_length += data_length;
1147         spin_unlock(&info->reassembly_queue_lock);
1148         info->count_reassembly_queue++;
1149         info->count_enqueue_reassembly_queue++;
1150 }
1151
1152 /*
1153  * Get the first entry at the front of reassembly queue
1154  * Caller is responsible for locking
1155  * return value: the first entry if any, NULL if queue is empty
1156  */
1157 static struct smbd_response *_get_first_reassembly(struct smbd_connection *info)
1158 {
1159         struct smbd_response *ret = NULL;
1160
1161         if (!list_empty(&info->reassembly_queue)) {
1162                 ret = list_first_entry(
1163                         &info->reassembly_queue,
1164                         struct smbd_response, list);
1165         }
1166         return ret;
1167 }
1168
1169 static struct smbd_response *get_empty_queue_buffer(
1170                 struct smbd_connection *info)
1171 {
1172         struct smbd_response *ret = NULL;
1173         unsigned long flags;
1174
1175         spin_lock_irqsave(&info->empty_packet_queue_lock, flags);
1176         if (!list_empty(&info->empty_packet_queue)) {
1177                 ret = list_first_entry(
1178                         &info->empty_packet_queue,
1179                         struct smbd_response, list);
1180                 list_del(&ret->list);
1181                 info->count_empty_packet_queue--;
1182         }
1183         spin_unlock_irqrestore(&info->empty_packet_queue_lock, flags);
1184
1185         return ret;
1186 }
1187
1188 /*
1189  * Get a receive buffer
1190  * For each remote send, we need to post a receive. The receive buffers are
1191  * pre-allocated in advance.
1192  * return value: the receive buffer, NULL if none is available
1193  */
1194 static struct smbd_response *get_receive_buffer(struct smbd_connection *info)
1195 {
1196         struct smbd_response *ret = NULL;
1197         unsigned long flags;
1198
1199         spin_lock_irqsave(&info->receive_queue_lock, flags);
1200         if (!list_empty(&info->receive_queue)) {
1201                 ret = list_first_entry(
1202                         &info->receive_queue,
1203                         struct smbd_response, list);
1204                 list_del(&ret->list);
1205                 info->count_receive_queue--;
1206                 info->count_get_receive_buffer++;
1207         }
1208         spin_unlock_irqrestore(&info->receive_queue_lock, flags);
1209
1210         return ret;
1211 }
1212
1213 /*
1214  * Return a receive buffer
1215  * Upon returning of a receive buffer, we can post new receive and extend
1216  * more receive credits to remote peer. This is done immediately after a
1217  * receive buffer is returned.
1218  */
1219 static void put_receive_buffer(
1220         struct smbd_connection *info, struct smbd_response *response)
1221 {
1222         unsigned long flags;
1223
1224         ib_dma_unmap_single(info->id->device, response->sge.addr,
1225                 response->sge.length, DMA_FROM_DEVICE);
1226
1227         spin_lock_irqsave(&info->receive_queue_lock, flags);
1228         list_add_tail(&response->list, &info->receive_queue);
1229         info->count_receive_queue++;
1230         info->count_put_receive_buffer++;
1231         spin_unlock_irqrestore(&info->receive_queue_lock, flags);
1232
1233         queue_work(info->workqueue, &info->post_send_credits_work);
1234 }
1235
1236 /* Preallocate all receive buffer on transport establishment */
1237 static int allocate_receive_buffers(struct smbd_connection *info, int num_buf)
1238 {
1239         int i;
1240         struct smbd_response *response;
1241
1242         INIT_LIST_HEAD(&info->reassembly_queue);
1243         spin_lock_init(&info->reassembly_queue_lock);
1244         info->reassembly_data_length = 0;
1245         info->reassembly_queue_length = 0;
1246
1247         INIT_LIST_HEAD(&info->receive_queue);
1248         spin_lock_init(&info->receive_queue_lock);
1249         info->count_receive_queue = 0;
1250
1251         INIT_LIST_HEAD(&info->empty_packet_queue);
1252         spin_lock_init(&info->empty_packet_queue_lock);
1253         info->count_empty_packet_queue = 0;
1254
1255         init_waitqueue_head(&info->wait_receive_queues);
1256
1257         for (i = 0; i < num_buf; i++) {
1258                 response = mempool_alloc(info->response_mempool, GFP_KERNEL);
1259                 if (!response)
1260                         goto allocate_failed;
1261
1262                 response->info = info;
1263                 list_add_tail(&response->list, &info->receive_queue);
1264                 info->count_receive_queue++;
1265         }
1266
1267         return 0;
1268
1269 allocate_failed:
1270         while (!list_empty(&info->receive_queue)) {
1271                 response = list_first_entry(
1272                                 &info->receive_queue,
1273                                 struct smbd_response, list);
1274                 list_del(&response->list);
1275                 info->count_receive_queue--;
1276
1277                 mempool_free(response, info->response_mempool);
1278         }
1279         return -ENOMEM;
1280 }
1281
1282 static void destroy_receive_buffers(struct smbd_connection *info)
1283 {
1284         struct smbd_response *response;
1285
1286         while ((response = get_receive_buffer(info)))
1287                 mempool_free(response, info->response_mempool);
1288
1289         while ((response = get_empty_queue_buffer(info)))
1290                 mempool_free(response, info->response_mempool);
1291 }
1292
1293 /* Implement idle connection timer [MS-SMBD] 3.1.6.2 */
1294 static void idle_connection_timer(struct work_struct *work)
1295 {
1296         struct smbd_connection *info = container_of(
1297                                         work, struct smbd_connection,
1298                                         idle_timer_work.work);
1299
1300         if (info->keep_alive_requested != KEEP_ALIVE_NONE) {
1301                 log_keep_alive(ERR,
1302                         "error status info->keep_alive_requested=%d\n",
1303                         info->keep_alive_requested);
1304                 smbd_disconnect_rdma_connection(info);
1305                 return;
1306         }
1307
1308         log_keep_alive(INFO, "about to send an empty idle message\n");
1309         smbd_post_send_empty(info);
1310
1311         /* Setup the next idle timeout work */
1312         queue_delayed_work(info->workqueue, &info->idle_timer_work,
1313                         info->keep_alive_interval*HZ);
1314 }
1315
1316 /*
1317  * Destroy the transport and related RDMA and memory resources
1318  * Need to go through all the pending counters and make sure on one is using
1319  * the transport while it is destroyed
1320  */
1321 void smbd_destroy(struct TCP_Server_Info *server)
1322 {
1323         struct smbd_connection *info = server->smbd_conn;
1324         struct smbd_response *response;
1325         unsigned long flags;
1326
1327         if (!info) {
1328                 log_rdma_event(INFO, "rdma session already destroyed\n");
1329                 return;
1330         }
1331
1332         log_rdma_event(INFO, "destroying rdma session\n");
1333         if (info->transport_status != SMBD_DISCONNECTED) {
1334                 rdma_disconnect(server->smbd_conn->id);
1335                 log_rdma_event(INFO, "wait for transport being disconnected\n");
1336                 wait_event_interruptible(
1337                         info->disconn_wait,
1338                         info->transport_status == SMBD_DISCONNECTED);
1339         }
1340
1341         log_rdma_event(INFO, "destroying qp\n");
1342         ib_drain_qp(info->id->qp);
1343         rdma_destroy_qp(info->id);
1344
1345         log_rdma_event(INFO, "cancelling idle timer\n");
1346         cancel_delayed_work_sync(&info->idle_timer_work);
1347
1348         log_rdma_event(INFO, "wait for all send posted to IB to finish\n");
1349         wait_event(info->wait_send_pending,
1350                 atomic_read(&info->send_pending) == 0);
1351
1352         /* It's not posssible for upper layer to get to reassembly */
1353         log_rdma_event(INFO, "drain the reassembly queue\n");
1354         do {
1355                 spin_lock_irqsave(&info->reassembly_queue_lock, flags);
1356                 response = _get_first_reassembly(info);
1357                 if (response) {
1358                         list_del(&response->list);
1359                         spin_unlock_irqrestore(
1360                                 &info->reassembly_queue_lock, flags);
1361                         put_receive_buffer(info, response);
1362                 } else
1363                         spin_unlock_irqrestore(
1364                                 &info->reassembly_queue_lock, flags);
1365         } while (response);
1366         info->reassembly_data_length = 0;
1367
1368         log_rdma_event(INFO, "free receive buffers\n");
1369         wait_event(info->wait_receive_queues,
1370                 info->count_receive_queue + info->count_empty_packet_queue
1371                         == info->receive_credit_max);
1372         destroy_receive_buffers(info);
1373
1374         /*
1375          * For performance reasons, memory registration and deregistration
1376          * are not locked by srv_mutex. It is possible some processes are
1377          * blocked on transport srv_mutex while holding memory registration.
1378          * Release the transport srv_mutex to allow them to hit the failure
1379          * path when sending data, and then release memory registartions.
1380          */
1381         log_rdma_event(INFO, "freeing mr list\n");
1382         wake_up_interruptible_all(&info->wait_mr);
1383         while (atomic_read(&info->mr_used_count)) {
1384                 mutex_unlock(&server->srv_mutex);
1385                 msleep(1000);
1386                 mutex_lock(&server->srv_mutex);
1387         }
1388         destroy_mr_list(info);
1389
1390         ib_free_cq(info->send_cq);
1391         ib_free_cq(info->recv_cq);
1392         ib_dealloc_pd(info->pd);
1393         rdma_destroy_id(info->id);
1394
1395         /* free mempools */
1396         mempool_destroy(info->request_mempool);
1397         kmem_cache_destroy(info->request_cache);
1398
1399         mempool_destroy(info->response_mempool);
1400         kmem_cache_destroy(info->response_cache);
1401
1402         info->transport_status = SMBD_DESTROYED;
1403
1404         destroy_workqueue(info->workqueue);
1405         log_rdma_event(INFO,  "rdma session destroyed\n");
1406         kfree(info);
1407         server->smbd_conn = NULL;
1408 }
1409
1410 /*
1411  * Reconnect this SMBD connection, called from upper layer
1412  * return value: 0 on success, or actual error code
1413  */
1414 int smbd_reconnect(struct TCP_Server_Info *server)
1415 {
1416         log_rdma_event(INFO, "reconnecting rdma session\n");
1417
1418         if (!server->smbd_conn) {
1419                 log_rdma_event(INFO, "rdma session already destroyed\n");
1420                 goto create_conn;
1421         }
1422
1423         /*
1424          * This is possible if transport is disconnected and we haven't received
1425          * notification from RDMA, but upper layer has detected timeout
1426          */
1427         if (server->smbd_conn->transport_status == SMBD_CONNECTED) {
1428                 log_rdma_event(INFO, "disconnecting transport\n");
1429                 smbd_destroy(server);
1430         }
1431
1432 create_conn:
1433         log_rdma_event(INFO, "creating rdma session\n");
1434         server->smbd_conn = smbd_get_connection(
1435                 server, (struct sockaddr *) &server->dstaddr);
1436
1437         if (server->smbd_conn)
1438                 cifs_dbg(VFS, "RDMA transport re-established\n");
1439
1440         return server->smbd_conn ? 0 : -ENOENT;
1441 }
1442
1443 static void destroy_caches_and_workqueue(struct smbd_connection *info)
1444 {
1445         destroy_receive_buffers(info);
1446         destroy_workqueue(info->workqueue);
1447         mempool_destroy(info->response_mempool);
1448         kmem_cache_destroy(info->response_cache);
1449         mempool_destroy(info->request_mempool);
1450         kmem_cache_destroy(info->request_cache);
1451 }
1452
1453 #define MAX_NAME_LEN    80
1454 static int allocate_caches_and_workqueue(struct smbd_connection *info)
1455 {
1456         char name[MAX_NAME_LEN];
1457         int rc;
1458
1459         scnprintf(name, MAX_NAME_LEN, "smbd_request_%p", info);
1460         info->request_cache =
1461                 kmem_cache_create(
1462                         name,
1463                         sizeof(struct smbd_request) +
1464                                 sizeof(struct smbd_data_transfer),
1465                         0, SLAB_HWCACHE_ALIGN, NULL);
1466         if (!info->request_cache)
1467                 return -ENOMEM;
1468
1469         info->request_mempool =
1470                 mempool_create(info->send_credit_target, mempool_alloc_slab,
1471                         mempool_free_slab, info->request_cache);
1472         if (!info->request_mempool)
1473                 goto out1;
1474
1475         scnprintf(name, MAX_NAME_LEN, "smbd_response_%p", info);
1476         info->response_cache =
1477                 kmem_cache_create(
1478                         name,
1479                         sizeof(struct smbd_response) +
1480                                 info->max_receive_size,
1481                         0, SLAB_HWCACHE_ALIGN, NULL);
1482         if (!info->response_cache)
1483                 goto out2;
1484
1485         info->response_mempool =
1486                 mempool_create(info->receive_credit_max, mempool_alloc_slab,
1487                        mempool_free_slab, info->response_cache);
1488         if (!info->response_mempool)
1489                 goto out3;
1490
1491         scnprintf(name, MAX_NAME_LEN, "smbd_%p", info);
1492         info->workqueue = create_workqueue(name);
1493         if (!info->workqueue)
1494                 goto out4;
1495
1496         rc = allocate_receive_buffers(info, info->receive_credit_max);
1497         if (rc) {
1498                 log_rdma_event(ERR, "failed to allocate receive buffers\n");
1499                 goto out5;
1500         }
1501
1502         return 0;
1503
1504 out5:
1505         destroy_workqueue(info->workqueue);
1506 out4:
1507         mempool_destroy(info->response_mempool);
1508 out3:
1509         kmem_cache_destroy(info->response_cache);
1510 out2:
1511         mempool_destroy(info->request_mempool);
1512 out1:
1513         kmem_cache_destroy(info->request_cache);
1514         return -ENOMEM;
1515 }
1516
1517 /* Create a SMBD connection, called by upper layer */
1518 static struct smbd_connection *_smbd_get_connection(
1519         struct TCP_Server_Info *server, struct sockaddr *dstaddr, int port)
1520 {
1521         int rc;
1522         struct smbd_connection *info;
1523         struct rdma_conn_param conn_param;
1524         struct ib_qp_init_attr qp_attr;
1525         struct sockaddr_in *addr_in = (struct sockaddr_in *) dstaddr;
1526         struct ib_port_immutable port_immutable;
1527         u32 ird_ord_hdr[2];
1528
1529         info = kzalloc(sizeof(struct smbd_connection), GFP_KERNEL);
1530         if (!info)
1531                 return NULL;
1532
1533         info->transport_status = SMBD_CONNECTING;
1534         rc = smbd_ia_open(info, dstaddr, port);
1535         if (rc) {
1536                 log_rdma_event(INFO, "smbd_ia_open rc=%d\n", rc);
1537                 goto create_id_failed;
1538         }
1539
1540         if (smbd_send_credit_target > info->id->device->attrs.max_cqe ||
1541             smbd_send_credit_target > info->id->device->attrs.max_qp_wr) {
1542                 log_rdma_event(ERR, "consider lowering send_credit_target = %d. Possible CQE overrun, device reporting max_cpe %d max_qp_wr %d\n",
1543                                smbd_send_credit_target,
1544                                info->id->device->attrs.max_cqe,
1545                                info->id->device->attrs.max_qp_wr);
1546                 goto config_failed;
1547         }
1548
1549         if (smbd_receive_credit_max > info->id->device->attrs.max_cqe ||
1550             smbd_receive_credit_max > info->id->device->attrs.max_qp_wr) {
1551                 log_rdma_event(ERR, "consider lowering receive_credit_max = %d. Possible CQE overrun, device reporting max_cpe %d max_qp_wr %d\n",
1552                                smbd_receive_credit_max,
1553                                info->id->device->attrs.max_cqe,
1554                                info->id->device->attrs.max_qp_wr);
1555                 goto config_failed;
1556         }
1557
1558         info->receive_credit_max = smbd_receive_credit_max;
1559         info->send_credit_target = smbd_send_credit_target;
1560         info->max_send_size = smbd_max_send_size;
1561         info->max_fragmented_recv_size = smbd_max_fragmented_recv_size;
1562         info->max_receive_size = smbd_max_receive_size;
1563         info->keep_alive_interval = smbd_keep_alive_interval;
1564
1565         if (info->id->device->attrs.max_send_sge < SMBDIRECT_MAX_SGE) {
1566                 log_rdma_event(ERR,
1567                         "warning: device max_send_sge = %d too small\n",
1568                         info->id->device->attrs.max_send_sge);
1569                 log_rdma_event(ERR, "Queue Pair creation may fail\n");
1570         }
1571         if (info->id->device->attrs.max_recv_sge < SMBDIRECT_MAX_SGE) {
1572                 log_rdma_event(ERR,
1573                         "warning: device max_recv_sge = %d too small\n",
1574                         info->id->device->attrs.max_recv_sge);
1575                 log_rdma_event(ERR, "Queue Pair creation may fail\n");
1576         }
1577
1578         info->send_cq = NULL;
1579         info->recv_cq = NULL;
1580         info->send_cq =
1581                 ib_alloc_cq_any(info->id->device, info,
1582                                 info->send_credit_target, IB_POLL_SOFTIRQ);
1583         if (IS_ERR(info->send_cq)) {
1584                 info->send_cq = NULL;
1585                 goto alloc_cq_failed;
1586         }
1587
1588         info->recv_cq =
1589                 ib_alloc_cq_any(info->id->device, info,
1590                                 info->receive_credit_max, IB_POLL_SOFTIRQ);
1591         if (IS_ERR(info->recv_cq)) {
1592                 info->recv_cq = NULL;
1593                 goto alloc_cq_failed;
1594         }
1595
1596         memset(&qp_attr, 0, sizeof(qp_attr));
1597         qp_attr.event_handler = smbd_qp_async_error_upcall;
1598         qp_attr.qp_context = info;
1599         qp_attr.cap.max_send_wr = info->send_credit_target;
1600         qp_attr.cap.max_recv_wr = info->receive_credit_max;
1601         qp_attr.cap.max_send_sge = SMBDIRECT_MAX_SGE;
1602         qp_attr.cap.max_recv_sge = SMBDIRECT_MAX_SGE;
1603         qp_attr.cap.max_inline_data = 0;
1604         qp_attr.sq_sig_type = IB_SIGNAL_REQ_WR;
1605         qp_attr.qp_type = IB_QPT_RC;
1606         qp_attr.send_cq = info->send_cq;
1607         qp_attr.recv_cq = info->recv_cq;
1608         qp_attr.port_num = ~0;
1609
1610         rc = rdma_create_qp(info->id, info->pd, &qp_attr);
1611         if (rc) {
1612                 log_rdma_event(ERR, "rdma_create_qp failed %i\n", rc);
1613                 goto create_qp_failed;
1614         }
1615
1616         memset(&conn_param, 0, sizeof(conn_param));
1617         conn_param.initiator_depth = 0;
1618
1619         conn_param.responder_resources =
1620                 info->id->device->attrs.max_qp_rd_atom
1621                         < SMBD_CM_RESPONDER_RESOURCES ?
1622                 info->id->device->attrs.max_qp_rd_atom :
1623                 SMBD_CM_RESPONDER_RESOURCES;
1624         info->responder_resources = conn_param.responder_resources;
1625         log_rdma_mr(INFO, "responder_resources=%d\n",
1626                 info->responder_resources);
1627
1628         /* Need to send IRD/ORD in private data for iWARP */
1629         info->id->device->ops.get_port_immutable(
1630                 info->id->device, info->id->port_num, &port_immutable);
1631         if (port_immutable.core_cap_flags & RDMA_CORE_PORT_IWARP) {
1632                 ird_ord_hdr[0] = info->responder_resources;
1633                 ird_ord_hdr[1] = 1;
1634                 conn_param.private_data = ird_ord_hdr;
1635                 conn_param.private_data_len = sizeof(ird_ord_hdr);
1636         } else {
1637                 conn_param.private_data = NULL;
1638                 conn_param.private_data_len = 0;
1639         }
1640
1641         conn_param.retry_count = SMBD_CM_RETRY;
1642         conn_param.rnr_retry_count = SMBD_CM_RNR_RETRY;
1643         conn_param.flow_control = 0;
1644
1645         log_rdma_event(INFO, "connecting to IP %pI4 port %d\n",
1646                 &addr_in->sin_addr, port);
1647
1648         init_waitqueue_head(&info->conn_wait);
1649         init_waitqueue_head(&info->disconn_wait);
1650         init_waitqueue_head(&info->wait_reassembly_queue);
1651         rc = rdma_connect(info->id, &conn_param);
1652         if (rc) {
1653                 log_rdma_event(ERR, "rdma_connect() failed with %i\n", rc);
1654                 goto rdma_connect_failed;
1655         }
1656
1657         wait_event_interruptible(
1658                 info->conn_wait, info->transport_status != SMBD_CONNECTING);
1659
1660         if (info->transport_status != SMBD_CONNECTED) {
1661                 log_rdma_event(ERR, "rdma_connect failed port=%d\n", port);
1662                 goto rdma_connect_failed;
1663         }
1664
1665         log_rdma_event(INFO, "rdma_connect connected\n");
1666
1667         rc = allocate_caches_and_workqueue(info);
1668         if (rc) {
1669                 log_rdma_event(ERR, "cache allocation failed\n");
1670                 goto allocate_cache_failed;
1671         }
1672
1673         init_waitqueue_head(&info->wait_send_queue);
1674         INIT_DELAYED_WORK(&info->idle_timer_work, idle_connection_timer);
1675         queue_delayed_work(info->workqueue, &info->idle_timer_work,
1676                 info->keep_alive_interval*HZ);
1677
1678         init_waitqueue_head(&info->wait_send_pending);
1679         atomic_set(&info->send_pending, 0);
1680
1681         init_waitqueue_head(&info->wait_post_send);
1682
1683         INIT_WORK(&info->disconnect_work, smbd_disconnect_rdma_work);
1684         INIT_WORK(&info->post_send_credits_work, smbd_post_send_credits);
1685         info->new_credits_offered = 0;
1686         spin_lock_init(&info->lock_new_credits_offered);
1687
1688         rc = smbd_negotiate(info);
1689         if (rc) {
1690                 log_rdma_event(ERR, "smbd_negotiate rc=%d\n", rc);
1691                 goto negotiation_failed;
1692         }
1693
1694         rc = allocate_mr_list(info);
1695         if (rc) {
1696                 log_rdma_mr(ERR, "memory registration allocation failed\n");
1697                 goto allocate_mr_failed;
1698         }
1699
1700         return info;
1701
1702 allocate_mr_failed:
1703         /* At this point, need to a full transport shutdown */
1704         server->smbd_conn = info;
1705         smbd_destroy(server);
1706         return NULL;
1707
1708 negotiation_failed:
1709         cancel_delayed_work_sync(&info->idle_timer_work);
1710         destroy_caches_and_workqueue(info);
1711         info->transport_status = SMBD_NEGOTIATE_FAILED;
1712         init_waitqueue_head(&info->conn_wait);
1713         rdma_disconnect(info->id);
1714         wait_event(info->conn_wait,
1715                 info->transport_status == SMBD_DISCONNECTED);
1716
1717 allocate_cache_failed:
1718 rdma_connect_failed:
1719         rdma_destroy_qp(info->id);
1720
1721 create_qp_failed:
1722 alloc_cq_failed:
1723         if (info->send_cq)
1724                 ib_free_cq(info->send_cq);
1725         if (info->recv_cq)
1726                 ib_free_cq(info->recv_cq);
1727
1728 config_failed:
1729         ib_dealloc_pd(info->pd);
1730         rdma_destroy_id(info->id);
1731
1732 create_id_failed:
1733         kfree(info);
1734         return NULL;
1735 }
1736
1737 struct smbd_connection *smbd_get_connection(
1738         struct TCP_Server_Info *server, struct sockaddr *dstaddr)
1739 {
1740         struct smbd_connection *ret;
1741         int port = SMBD_PORT;
1742
1743 try_again:
1744         ret = _smbd_get_connection(server, dstaddr, port);
1745
1746         /* Try SMB_PORT if SMBD_PORT doesn't work */
1747         if (!ret && port == SMBD_PORT) {
1748                 port = SMB_PORT;
1749                 goto try_again;
1750         }
1751         return ret;
1752 }
1753
1754 /*
1755  * Receive data from receive reassembly queue
1756  * All the incoming data packets are placed in reassembly queue
1757  * buf: the buffer to read data into
1758  * size: the length of data to read
1759  * return value: actual data read
1760  * Note: this implementation copies the data from reassebmly queue to receive
1761  * buffers used by upper layer. This is not the optimal code path. A better way
1762  * to do it is to not have upper layer allocate its receive buffers but rather
1763  * borrow the buffer from reassembly queue, and return it after data is
1764  * consumed. But this will require more changes to upper layer code, and also
1765  * need to consider packet boundaries while they still being reassembled.
1766  */
1767 static int smbd_recv_buf(struct smbd_connection *info, char *buf,
1768                 unsigned int size)
1769 {
1770         struct smbd_response *response;
1771         struct smbd_data_transfer *data_transfer;
1772         int to_copy, to_read, data_read, offset;
1773         u32 data_length, remaining_data_length, data_offset;
1774         int rc;
1775
1776 again:
1777         /*
1778          * No need to hold the reassembly queue lock all the time as we are
1779          * the only one reading from the front of the queue. The transport
1780          * may add more entries to the back of the queue at the same time
1781          */
1782         log_read(INFO, "size=%d info->reassembly_data_length=%d\n", size,
1783                 info->reassembly_data_length);
1784         if (info->reassembly_data_length >= size) {
1785                 int queue_length;
1786                 int queue_removed = 0;
1787
1788                 /*
1789                  * Need to make sure reassembly_data_length is read before
1790                  * reading reassembly_queue_length and calling
1791                  * _get_first_reassembly. This call is lock free
1792                  * as we never read at the end of the queue which are being
1793                  * updated in SOFTIRQ as more data is received
1794                  */
1795                 virt_rmb();
1796                 queue_length = info->reassembly_queue_length;
1797                 data_read = 0;
1798                 to_read = size;
1799                 offset = info->first_entry_offset;
1800                 while (data_read < size) {
1801                         response = _get_first_reassembly(info);
1802                         data_transfer = smbd_response_payload(response);
1803                         data_length = le32_to_cpu(data_transfer->data_length);
1804                         remaining_data_length =
1805                                 le32_to_cpu(
1806                                         data_transfer->remaining_data_length);
1807                         data_offset = le32_to_cpu(data_transfer->data_offset);
1808
1809                         /*
1810                          * The upper layer expects RFC1002 length at the
1811                          * beginning of the payload. Return it to indicate
1812                          * the total length of the packet. This minimize the
1813                          * change to upper layer packet processing logic. This
1814                          * will be eventually remove when an intermediate
1815                          * transport layer is added
1816                          */
1817                         if (response->first_segment && size == 4) {
1818                                 unsigned int rfc1002_len =
1819                                         data_length + remaining_data_length;
1820                                 *((__be32 *)buf) = cpu_to_be32(rfc1002_len);
1821                                 data_read = 4;
1822                                 response->first_segment = false;
1823                                 log_read(INFO, "returning rfc1002 length %d\n",
1824                                         rfc1002_len);
1825                                 goto read_rfc1002_done;
1826                         }
1827
1828                         to_copy = min_t(int, data_length - offset, to_read);
1829                         memcpy(
1830                                 buf + data_read,
1831                                 (char *)data_transfer + data_offset + offset,
1832                                 to_copy);
1833
1834                         /* move on to the next buffer? */
1835                         if (to_copy == data_length - offset) {
1836                                 queue_length--;
1837                                 /*
1838                                  * No need to lock if we are not at the
1839                                  * end of the queue
1840                                  */
1841                                 if (queue_length)
1842                                         list_del(&response->list);
1843                                 else {
1844                                         spin_lock_irq(
1845                                                 &info->reassembly_queue_lock);
1846                                         list_del(&response->list);
1847                                         spin_unlock_irq(
1848                                                 &info->reassembly_queue_lock);
1849                                 }
1850                                 queue_removed++;
1851                                 info->count_reassembly_queue--;
1852                                 info->count_dequeue_reassembly_queue++;
1853                                 put_receive_buffer(info, response);
1854                                 offset = 0;
1855                                 log_read(INFO, "put_receive_buffer offset=0\n");
1856                         } else
1857                                 offset += to_copy;
1858
1859                         to_read -= to_copy;
1860                         data_read += to_copy;
1861
1862                         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",
1863                                  to_copy, data_length - offset,
1864                                  to_read, data_read, offset);
1865                 }
1866
1867                 spin_lock_irq(&info->reassembly_queue_lock);
1868                 info->reassembly_data_length -= data_read;
1869                 info->reassembly_queue_length -= queue_removed;
1870                 spin_unlock_irq(&info->reassembly_queue_lock);
1871
1872                 info->first_entry_offset = offset;
1873                 log_read(INFO, "returning to thread data_read=%d reassembly_data_length=%d first_entry_offset=%d\n",
1874                          data_read, info->reassembly_data_length,
1875                          info->first_entry_offset);
1876 read_rfc1002_done:
1877                 return data_read;
1878         }
1879
1880         log_read(INFO, "wait_event on more data\n");
1881         rc = wait_event_interruptible(
1882                 info->wait_reassembly_queue,
1883                 info->reassembly_data_length >= size ||
1884                         info->transport_status != SMBD_CONNECTED);
1885         /* Don't return any data if interrupted */
1886         if (rc)
1887                 return rc;
1888
1889         if (info->transport_status != SMBD_CONNECTED) {
1890                 log_read(ERR, "disconnected\n");
1891                 return -ECONNABORTED;
1892         }
1893
1894         goto again;
1895 }
1896
1897 /*
1898  * Receive a page from receive reassembly queue
1899  * page: the page to read data into
1900  * to_read: the length of data to read
1901  * return value: actual data read
1902  */
1903 static int smbd_recv_page(struct smbd_connection *info,
1904                 struct page *page, unsigned int page_offset,
1905                 unsigned int to_read)
1906 {
1907         int ret;
1908         char *to_address;
1909         void *page_address;
1910
1911         /* make sure we have the page ready for read */
1912         ret = wait_event_interruptible(
1913                 info->wait_reassembly_queue,
1914                 info->reassembly_data_length >= to_read ||
1915                         info->transport_status != SMBD_CONNECTED);
1916         if (ret)
1917                 return ret;
1918
1919         /* now we can read from reassembly queue and not sleep */
1920         page_address = kmap_atomic(page);
1921         to_address = (char *) page_address + page_offset;
1922
1923         log_read(INFO, "reading from page=%p address=%p to_read=%d\n",
1924                 page, to_address, to_read);
1925
1926         ret = smbd_recv_buf(info, to_address, to_read);
1927         kunmap_atomic(page_address);
1928
1929         return ret;
1930 }
1931
1932 /*
1933  * Receive data from transport
1934  * msg: a msghdr point to the buffer, can be ITER_KVEC or ITER_BVEC
1935  * return: total bytes read, or 0. SMB Direct will not do partial read.
1936  */
1937 int smbd_recv(struct smbd_connection *info, struct msghdr *msg)
1938 {
1939         char *buf;
1940         struct page *page;
1941         unsigned int to_read, page_offset;
1942         int rc;
1943
1944         if (iov_iter_rw(&msg->msg_iter) == WRITE) {
1945                 /* It's a bug in upper layer to get there */
1946                 cifs_dbg(VFS, "Invalid msg iter dir %u\n",
1947                          iov_iter_rw(&msg->msg_iter));
1948                 rc = -EINVAL;
1949                 goto out;
1950         }
1951
1952         switch (iov_iter_type(&msg->msg_iter)) {
1953         case ITER_KVEC:
1954                 buf = msg->msg_iter.kvec->iov_base;
1955                 to_read = msg->msg_iter.kvec->iov_len;
1956                 rc = smbd_recv_buf(info, buf, to_read);
1957                 break;
1958
1959         case ITER_BVEC:
1960                 page = msg->msg_iter.bvec->bv_page;
1961                 page_offset = msg->msg_iter.bvec->bv_offset;
1962                 to_read = msg->msg_iter.bvec->bv_len;
1963                 rc = smbd_recv_page(info, page, page_offset, to_read);
1964                 break;
1965
1966         default:
1967                 /* It's a bug in upper layer to get there */
1968                 cifs_dbg(VFS, "Invalid msg type %d\n",
1969                          iov_iter_type(&msg->msg_iter));
1970                 rc = -EINVAL;
1971         }
1972
1973 out:
1974         /* SMBDirect will read it all or nothing */
1975         if (rc > 0)
1976                 msg->msg_iter.count = 0;
1977         return rc;
1978 }
1979
1980 /*
1981  * Send data to transport
1982  * Each rqst is transported as a SMBDirect payload
1983  * rqst: the data to write
1984  * return value: 0 if successfully write, otherwise error code
1985  */
1986 int smbd_send(struct TCP_Server_Info *server,
1987         int num_rqst, struct smb_rqst *rqst_array)
1988 {
1989         struct smbd_connection *info = server->smbd_conn;
1990         struct kvec vec;
1991         int nvecs;
1992         int size;
1993         unsigned int buflen, remaining_data_length;
1994         int start, i, j;
1995         int max_iov_size =
1996                 info->max_send_size - sizeof(struct smbd_data_transfer);
1997         struct kvec *iov;
1998         int rc;
1999         struct smb_rqst *rqst;
2000         int rqst_idx;
2001
2002         if (info->transport_status != SMBD_CONNECTED) {
2003                 rc = -EAGAIN;
2004                 goto done;
2005         }
2006
2007         /*
2008          * Add in the page array if there is one. The caller needs to set
2009          * rq_tailsz to PAGE_SIZE when the buffer has multiple pages and
2010          * ends at page boundary
2011          */
2012         remaining_data_length = 0;
2013         for (i = 0; i < num_rqst; i++)
2014                 remaining_data_length += smb_rqst_len(server, &rqst_array[i]);
2015
2016         if (remaining_data_length > info->max_fragmented_send_size) {
2017                 log_write(ERR, "payload size %d > max size %d\n",
2018                         remaining_data_length, info->max_fragmented_send_size);
2019                 rc = -EINVAL;
2020                 goto done;
2021         }
2022
2023         log_write(INFO, "num_rqst=%d total length=%u\n",
2024                         num_rqst, remaining_data_length);
2025
2026         rqst_idx = 0;
2027 next_rqst:
2028         rqst = &rqst_array[rqst_idx];
2029         iov = rqst->rq_iov;
2030
2031         cifs_dbg(FYI, "Sending smb (RDMA): idx=%d smb_len=%lu\n",
2032                 rqst_idx, smb_rqst_len(server, rqst));
2033         for (i = 0; i < rqst->rq_nvec; i++)
2034                 dump_smb(iov[i].iov_base, iov[i].iov_len);
2035
2036
2037         log_write(INFO, "rqst_idx=%d nvec=%d rqst->rq_npages=%d rq_pagesz=%d rq_tailsz=%d buflen=%lu\n",
2038                   rqst_idx, rqst->rq_nvec, rqst->rq_npages, rqst->rq_pagesz,
2039                   rqst->rq_tailsz, smb_rqst_len(server, rqst));
2040
2041         start = i = 0;
2042         buflen = 0;
2043         while (true) {
2044                 buflen += iov[i].iov_len;
2045                 if (buflen > max_iov_size) {
2046                         if (i > start) {
2047                                 remaining_data_length -=
2048                                         (buflen-iov[i].iov_len);
2049                                 log_write(INFO, "sending iov[] from start=%d i=%d nvecs=%d remaining_data_length=%d\n",
2050                                           start, i, i - start,
2051                                           remaining_data_length);
2052                                 rc = smbd_post_send_data(
2053                                         info, &iov[start], i-start,
2054                                         remaining_data_length);
2055                                 if (rc)
2056                                         goto done;
2057                         } else {
2058                                 /* iov[start] is too big, break it */
2059                                 nvecs = (buflen+max_iov_size-1)/max_iov_size;
2060                                 log_write(INFO, "iov[%d] iov_base=%p buflen=%d break to %d vectors\n",
2061                                           start, iov[start].iov_base,
2062                                           buflen, nvecs);
2063                                 for (j = 0; j < nvecs; j++) {
2064                                         vec.iov_base =
2065                                                 (char *)iov[start].iov_base +
2066                                                 j*max_iov_size;
2067                                         vec.iov_len = max_iov_size;
2068                                         if (j == nvecs-1)
2069                                                 vec.iov_len =
2070                                                         buflen -
2071                                                         max_iov_size*(nvecs-1);
2072                                         remaining_data_length -= vec.iov_len;
2073                                         log_write(INFO,
2074                                                 "sending vec j=%d iov_base=%p iov_len=%zu remaining_data_length=%d\n",
2075                                                   j, vec.iov_base, vec.iov_len,
2076                                                   remaining_data_length);
2077                                         rc = smbd_post_send_data(
2078                                                 info, &vec, 1,
2079                                                 remaining_data_length);
2080                                         if (rc)
2081                                                 goto done;
2082                                 }
2083                                 i++;
2084                                 if (i == rqst->rq_nvec)
2085                                         break;
2086                         }
2087                         start = i;
2088                         buflen = 0;
2089                 } else {
2090                         i++;
2091                         if (i == rqst->rq_nvec) {
2092                                 /* send out all remaining vecs */
2093                                 remaining_data_length -= buflen;
2094                                 log_write(INFO, "sending iov[] from start=%d i=%d nvecs=%d remaining_data_length=%d\n",
2095                                           start, i, i - start,
2096                                           remaining_data_length);
2097                                 rc = smbd_post_send_data(info, &iov[start],
2098                                         i-start, remaining_data_length);
2099                                 if (rc)
2100                                         goto done;
2101                                 break;
2102                         }
2103                 }
2104                 log_write(INFO, "looping i=%d buflen=%d\n", i, buflen);
2105         }
2106
2107         /* now sending pages if there are any */
2108         for (i = 0; i < rqst->rq_npages; i++) {
2109                 unsigned int offset;
2110
2111                 rqst_page_get_length(rqst, i, &buflen, &offset);
2112                 nvecs = (buflen + max_iov_size - 1) / max_iov_size;
2113                 log_write(INFO, "sending pages buflen=%d nvecs=%d\n",
2114                         buflen, nvecs);
2115                 for (j = 0; j < nvecs; j++) {
2116                         size = max_iov_size;
2117                         if (j == nvecs-1)
2118                                 size = buflen - j*max_iov_size;
2119                         remaining_data_length -= size;
2120                         log_write(INFO, "sending pages i=%d offset=%d size=%d remaining_data_length=%d\n",
2121                                   i, j * max_iov_size + offset, size,
2122                                   remaining_data_length);
2123                         rc = smbd_post_send_page(
2124                                 info, rqst->rq_pages[i],
2125                                 j*max_iov_size + offset,
2126                                 size, remaining_data_length);
2127                         if (rc)
2128                                 goto done;
2129                 }
2130         }
2131
2132         rqst_idx++;
2133         if (rqst_idx < num_rqst)
2134                 goto next_rqst;
2135
2136 done:
2137         /*
2138          * As an optimization, we don't wait for individual I/O to finish
2139          * before sending the next one.
2140          * Send them all and wait for pending send count to get to 0
2141          * that means all the I/Os have been out and we are good to return
2142          */
2143
2144         wait_event(info->wait_send_pending,
2145                 atomic_read(&info->send_pending) == 0);
2146
2147         return rc;
2148 }
2149
2150 static void register_mr_done(struct ib_cq *cq, struct ib_wc *wc)
2151 {
2152         struct smbd_mr *mr;
2153         struct ib_cqe *cqe;
2154
2155         if (wc->status) {
2156                 log_rdma_mr(ERR, "status=%d\n", wc->status);
2157                 cqe = wc->wr_cqe;
2158                 mr = container_of(cqe, struct smbd_mr, cqe);
2159                 smbd_disconnect_rdma_connection(mr->conn);
2160         }
2161 }
2162
2163 /*
2164  * The work queue function that recovers MRs
2165  * We need to call ib_dereg_mr() and ib_alloc_mr() before this MR can be used
2166  * again. Both calls are slow, so finish them in a workqueue. This will not
2167  * block I/O path.
2168  * There is one workqueue that recovers MRs, there is no need to lock as the
2169  * I/O requests calling smbd_register_mr will never update the links in the
2170  * mr_list.
2171  */
2172 static void smbd_mr_recovery_work(struct work_struct *work)
2173 {
2174         struct smbd_connection *info =
2175                 container_of(work, struct smbd_connection, mr_recovery_work);
2176         struct smbd_mr *smbdirect_mr;
2177         int rc;
2178
2179         list_for_each_entry(smbdirect_mr, &info->mr_list, list) {
2180                 if (smbdirect_mr->state == MR_ERROR) {
2181
2182                         /* recover this MR entry */
2183                         rc = ib_dereg_mr(smbdirect_mr->mr);
2184                         if (rc) {
2185                                 log_rdma_mr(ERR,
2186                                         "ib_dereg_mr failed rc=%x\n",
2187                                         rc);
2188                                 smbd_disconnect_rdma_connection(info);
2189                                 continue;
2190                         }
2191
2192                         smbdirect_mr->mr = ib_alloc_mr(
2193                                 info->pd, info->mr_type,
2194                                 info->max_frmr_depth);
2195                         if (IS_ERR(smbdirect_mr->mr)) {
2196                                 log_rdma_mr(ERR, "ib_alloc_mr failed mr_type=%x max_frmr_depth=%x\n",
2197                                             info->mr_type,
2198                                             info->max_frmr_depth);
2199                                 smbd_disconnect_rdma_connection(info);
2200                                 continue;
2201                         }
2202                 } else
2203                         /* This MR is being used, don't recover it */
2204                         continue;
2205
2206                 smbdirect_mr->state = MR_READY;
2207
2208                 /* smbdirect_mr->state is updated by this function
2209                  * and is read and updated by I/O issuing CPUs trying
2210                  * to get a MR, the call to atomic_inc_return
2211                  * implicates a memory barrier and guarantees this
2212                  * value is updated before waking up any calls to
2213                  * get_mr() from the I/O issuing CPUs
2214                  */
2215                 if (atomic_inc_return(&info->mr_ready_count) == 1)
2216                         wake_up_interruptible(&info->wait_mr);
2217         }
2218 }
2219
2220 static void destroy_mr_list(struct smbd_connection *info)
2221 {
2222         struct smbd_mr *mr, *tmp;
2223
2224         cancel_work_sync(&info->mr_recovery_work);
2225         list_for_each_entry_safe(mr, tmp, &info->mr_list, list) {
2226                 if (mr->state == MR_INVALIDATED)
2227                         ib_dma_unmap_sg(info->id->device, mr->sgl,
2228                                 mr->sgl_count, mr->dir);
2229                 ib_dereg_mr(mr->mr);
2230                 kfree(mr->sgl);
2231                 kfree(mr);
2232         }
2233 }
2234
2235 /*
2236  * Allocate MRs used for RDMA read/write
2237  * The number of MRs will not exceed hardware capability in responder_resources
2238  * All MRs are kept in mr_list. The MR can be recovered after it's used
2239  * Recovery is done in smbd_mr_recovery_work. The content of list entry changes
2240  * as MRs are used and recovered for I/O, but the list links will not change
2241  */
2242 static int allocate_mr_list(struct smbd_connection *info)
2243 {
2244         int i;
2245         struct smbd_mr *smbdirect_mr, *tmp;
2246
2247         INIT_LIST_HEAD(&info->mr_list);
2248         init_waitqueue_head(&info->wait_mr);
2249         spin_lock_init(&info->mr_list_lock);
2250         atomic_set(&info->mr_ready_count, 0);
2251         atomic_set(&info->mr_used_count, 0);
2252         init_waitqueue_head(&info->wait_for_mr_cleanup);
2253         INIT_WORK(&info->mr_recovery_work, smbd_mr_recovery_work);
2254         /* Allocate more MRs (2x) than hardware responder_resources */
2255         for (i = 0; i < info->responder_resources * 2; i++) {
2256                 smbdirect_mr = kzalloc(sizeof(*smbdirect_mr), GFP_KERNEL);
2257                 if (!smbdirect_mr)
2258                         goto out;
2259                 smbdirect_mr->mr = ib_alloc_mr(info->pd, info->mr_type,
2260                                         info->max_frmr_depth);
2261                 if (IS_ERR(smbdirect_mr->mr)) {
2262                         log_rdma_mr(ERR, "ib_alloc_mr failed mr_type=%x max_frmr_depth=%x\n",
2263                                     info->mr_type, info->max_frmr_depth);
2264                         goto out;
2265                 }
2266                 smbdirect_mr->sgl = kcalloc(
2267                                         info->max_frmr_depth,
2268                                         sizeof(struct scatterlist),
2269                                         GFP_KERNEL);
2270                 if (!smbdirect_mr->sgl) {
2271                         log_rdma_mr(ERR, "failed to allocate sgl\n");
2272                         ib_dereg_mr(smbdirect_mr->mr);
2273                         goto out;
2274                 }
2275                 smbdirect_mr->state = MR_READY;
2276                 smbdirect_mr->conn = info;
2277
2278                 list_add_tail(&smbdirect_mr->list, &info->mr_list);
2279                 atomic_inc(&info->mr_ready_count);
2280         }
2281         return 0;
2282
2283 out:
2284         kfree(smbdirect_mr);
2285
2286         list_for_each_entry_safe(smbdirect_mr, tmp, &info->mr_list, list) {
2287                 list_del(&smbdirect_mr->list);
2288                 ib_dereg_mr(smbdirect_mr->mr);
2289                 kfree(smbdirect_mr->sgl);
2290                 kfree(smbdirect_mr);
2291         }
2292         return -ENOMEM;
2293 }
2294
2295 /*
2296  * Get a MR from mr_list. This function waits until there is at least one
2297  * MR available in the list. It may access the list while the
2298  * smbd_mr_recovery_work is recovering the MR list. This doesn't need a lock
2299  * as they never modify the same places. However, there may be several CPUs
2300  * issueing I/O trying to get MR at the same time, mr_list_lock is used to
2301  * protect this situation.
2302  */
2303 static struct smbd_mr *get_mr(struct smbd_connection *info)
2304 {
2305         struct smbd_mr *ret;
2306         int rc;
2307 again:
2308         rc = wait_event_interruptible(info->wait_mr,
2309                 atomic_read(&info->mr_ready_count) ||
2310                 info->transport_status != SMBD_CONNECTED);
2311         if (rc) {
2312                 log_rdma_mr(ERR, "wait_event_interruptible rc=%x\n", rc);
2313                 return NULL;
2314         }
2315
2316         if (info->transport_status != SMBD_CONNECTED) {
2317                 log_rdma_mr(ERR, "info->transport_status=%x\n",
2318                         info->transport_status);
2319                 return NULL;
2320         }
2321
2322         spin_lock(&info->mr_list_lock);
2323         list_for_each_entry(ret, &info->mr_list, list) {
2324                 if (ret->state == MR_READY) {
2325                         ret->state = MR_REGISTERED;
2326                         spin_unlock(&info->mr_list_lock);
2327                         atomic_dec(&info->mr_ready_count);
2328                         atomic_inc(&info->mr_used_count);
2329                         return ret;
2330                 }
2331         }
2332
2333         spin_unlock(&info->mr_list_lock);
2334         /*
2335          * It is possible that we could fail to get MR because other processes may
2336          * try to acquire a MR at the same time. If this is the case, retry it.
2337          */
2338         goto again;
2339 }
2340
2341 /*
2342  * Register memory for RDMA read/write
2343  * pages[]: the list of pages to register memory with
2344  * num_pages: the number of pages to register
2345  * tailsz: if non-zero, the bytes to register in the last page
2346  * writing: true if this is a RDMA write (SMB read), false for RDMA read
2347  * need_invalidate: true if this MR needs to be locally invalidated after I/O
2348  * return value: the MR registered, NULL if failed.
2349  */
2350 struct smbd_mr *smbd_register_mr(
2351         struct smbd_connection *info, struct page *pages[], int num_pages,
2352         int offset, int tailsz, bool writing, bool need_invalidate)
2353 {
2354         struct smbd_mr *smbdirect_mr;
2355         int rc, i;
2356         enum dma_data_direction dir;
2357         struct ib_reg_wr *reg_wr;
2358
2359         if (num_pages > info->max_frmr_depth) {
2360                 log_rdma_mr(ERR, "num_pages=%d max_frmr_depth=%d\n",
2361                         num_pages, info->max_frmr_depth);
2362                 return NULL;
2363         }
2364
2365         smbdirect_mr = get_mr(info);
2366         if (!smbdirect_mr) {
2367                 log_rdma_mr(ERR, "get_mr returning NULL\n");
2368                 return NULL;
2369         }
2370         smbdirect_mr->need_invalidate = need_invalidate;
2371         smbdirect_mr->sgl_count = num_pages;
2372         sg_init_table(smbdirect_mr->sgl, num_pages);
2373
2374         log_rdma_mr(INFO, "num_pages=0x%x offset=0x%x tailsz=0x%x\n",
2375                         num_pages, offset, tailsz);
2376
2377         if (num_pages == 1) {
2378                 sg_set_page(&smbdirect_mr->sgl[0], pages[0], tailsz, offset);
2379                 goto skip_multiple_pages;
2380         }
2381
2382         /* We have at least two pages to register */
2383         sg_set_page(
2384                 &smbdirect_mr->sgl[0], pages[0], PAGE_SIZE - offset, offset);
2385         i = 1;
2386         while (i < num_pages - 1) {
2387                 sg_set_page(&smbdirect_mr->sgl[i], pages[i], PAGE_SIZE, 0);
2388                 i++;
2389         }
2390         sg_set_page(&smbdirect_mr->sgl[i], pages[i],
2391                 tailsz ? tailsz : PAGE_SIZE, 0);
2392
2393 skip_multiple_pages:
2394         dir = writing ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
2395         smbdirect_mr->dir = dir;
2396         rc = ib_dma_map_sg(info->id->device, smbdirect_mr->sgl, num_pages, dir);
2397         if (!rc) {
2398                 log_rdma_mr(ERR, "ib_dma_map_sg num_pages=%x dir=%x rc=%x\n",
2399                         num_pages, dir, rc);
2400                 goto dma_map_error;
2401         }
2402
2403         rc = ib_map_mr_sg(smbdirect_mr->mr, smbdirect_mr->sgl, num_pages,
2404                 NULL, PAGE_SIZE);
2405         if (rc != num_pages) {
2406                 log_rdma_mr(ERR,
2407                         "ib_map_mr_sg failed rc = %d num_pages = %x\n",
2408                         rc, num_pages);
2409                 goto map_mr_error;
2410         }
2411
2412         ib_update_fast_reg_key(smbdirect_mr->mr,
2413                 ib_inc_rkey(smbdirect_mr->mr->rkey));
2414         reg_wr = &smbdirect_mr->wr;
2415         reg_wr->wr.opcode = IB_WR_REG_MR;
2416         smbdirect_mr->cqe.done = register_mr_done;
2417         reg_wr->wr.wr_cqe = &smbdirect_mr->cqe;
2418         reg_wr->wr.num_sge = 0;
2419         reg_wr->wr.send_flags = IB_SEND_SIGNALED;
2420         reg_wr->mr = smbdirect_mr->mr;
2421         reg_wr->key = smbdirect_mr->mr->rkey;
2422         reg_wr->access = writing ?
2423                         IB_ACCESS_REMOTE_WRITE | IB_ACCESS_LOCAL_WRITE :
2424                         IB_ACCESS_REMOTE_READ;
2425
2426         /*
2427          * There is no need for waiting for complemtion on ib_post_send
2428          * on IB_WR_REG_MR. Hardware enforces a barrier and order of execution
2429          * on the next ib_post_send when we actaully send I/O to remote peer
2430          */
2431         rc = ib_post_send(info->id->qp, &reg_wr->wr, NULL);
2432         if (!rc)
2433                 return smbdirect_mr;
2434
2435         log_rdma_mr(ERR, "ib_post_send failed rc=%x reg_wr->key=%x\n",
2436                 rc, reg_wr->key);
2437
2438         /* If all failed, attempt to recover this MR by setting it MR_ERROR*/
2439 map_mr_error:
2440         ib_dma_unmap_sg(info->id->device, smbdirect_mr->sgl,
2441                 smbdirect_mr->sgl_count, smbdirect_mr->dir);
2442
2443 dma_map_error:
2444         smbdirect_mr->state = MR_ERROR;
2445         if (atomic_dec_and_test(&info->mr_used_count))
2446                 wake_up(&info->wait_for_mr_cleanup);
2447
2448         smbd_disconnect_rdma_connection(info);
2449
2450         return NULL;
2451 }
2452
2453 static void local_inv_done(struct ib_cq *cq, struct ib_wc *wc)
2454 {
2455         struct smbd_mr *smbdirect_mr;
2456         struct ib_cqe *cqe;
2457
2458         cqe = wc->wr_cqe;
2459         smbdirect_mr = container_of(cqe, struct smbd_mr, cqe);
2460         smbdirect_mr->state = MR_INVALIDATED;
2461         if (wc->status != IB_WC_SUCCESS) {
2462                 log_rdma_mr(ERR, "invalidate failed status=%x\n", wc->status);
2463                 smbdirect_mr->state = MR_ERROR;
2464         }
2465         complete(&smbdirect_mr->invalidate_done);
2466 }
2467
2468 /*
2469  * Deregister a MR after I/O is done
2470  * This function may wait if remote invalidation is not used
2471  * and we have to locally invalidate the buffer to prevent data is being
2472  * modified by remote peer after upper layer consumes it
2473  */
2474 int smbd_deregister_mr(struct smbd_mr *smbdirect_mr)
2475 {
2476         struct ib_send_wr *wr;
2477         struct smbd_connection *info = smbdirect_mr->conn;
2478         int rc = 0;
2479
2480         if (smbdirect_mr->need_invalidate) {
2481                 /* Need to finish local invalidation before returning */
2482                 wr = &smbdirect_mr->inv_wr;
2483                 wr->opcode = IB_WR_LOCAL_INV;
2484                 smbdirect_mr->cqe.done = local_inv_done;
2485                 wr->wr_cqe = &smbdirect_mr->cqe;
2486                 wr->num_sge = 0;
2487                 wr->ex.invalidate_rkey = smbdirect_mr->mr->rkey;
2488                 wr->send_flags = IB_SEND_SIGNALED;
2489
2490                 init_completion(&smbdirect_mr->invalidate_done);
2491                 rc = ib_post_send(info->id->qp, wr, NULL);
2492                 if (rc) {
2493                         log_rdma_mr(ERR, "ib_post_send failed rc=%x\n", rc);
2494                         smbd_disconnect_rdma_connection(info);
2495                         goto done;
2496                 }
2497                 wait_for_completion(&smbdirect_mr->invalidate_done);
2498                 smbdirect_mr->need_invalidate = false;
2499         } else
2500                 /*
2501                  * For remote invalidation, just set it to MR_INVALIDATED
2502                  * and defer to mr_recovery_work to recover the MR for next use
2503                  */
2504                 smbdirect_mr->state = MR_INVALIDATED;
2505
2506         if (smbdirect_mr->state == MR_INVALIDATED) {
2507                 ib_dma_unmap_sg(
2508                         info->id->device, smbdirect_mr->sgl,
2509                         smbdirect_mr->sgl_count,
2510                         smbdirect_mr->dir);
2511                 smbdirect_mr->state = MR_READY;
2512                 if (atomic_inc_return(&info->mr_ready_count) == 1)
2513                         wake_up_interruptible(&info->wait_mr);
2514         } else
2515                 /*
2516                  * Schedule the work to do MR recovery for future I/Os MR
2517                  * recovery is slow and don't want it to block current I/O
2518                  */
2519                 queue_work(info->workqueue, &info->mr_recovery_work);
2520
2521 done:
2522         if (atomic_dec_and_test(&info->mr_used_count))
2523                 wake_up(&info->wait_for_mr_cleanup);
2524
2525         return rc;
2526 }