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 "
 298                 "negotiated_version %u credits_requested %u "
 299                 "credits_granted %u status %u max_readwrite_size %u "
 300                 "preferred_send_size %u max_receive_size %u "
 301                 "max_fragmented_size %u\n",
 302                 resp->min_version, resp->max_version, resp->negotiated_version,
 303                 resp->credits_requested, resp->credits_granted, resp->status,
 304                 resp->max_readwrite_size, resp->preferred_send_size,
 305                 resp->max_receive_size, resp->max_fragmented_size);
 306 }
 307
 308 /*
 309  * Process a negotiation response message, according to [MS-SMBD]3.1.5.7
 310  * response, packet_length: the negotiation response message
 311  * return value: true if negotiation is a success, false if failed
 312  */
 313 static bool process_negotiation_response(
 314                 struct smbd_response *response, int packet_length)
 315 {
 316         struct smbd_connection *info = response->info;
 317         struct smbd_negotiate_resp *packet = smbd_response_payload(response);
 318
 319         if (packet_length < sizeof(struct smbd_negotiate_resp)) {
 320                 log_rdma_event(ERR,
 321                         "error: packet_length=%d\n", packet_length);
 322                 return false;
 323         }
 324
 325         if (le16_to_cpu(packet->negotiated_version) != SMBD_V1) {
 326                 log_rdma_event(ERR, "error: negotiated_version=%x\n",
 327                         le16_to_cpu(packet->negotiated_version));
 328                 return false;
 329         }
 330         info->protocol = le16_to_cpu(packet->negotiated_version);
 331
 332         if (packet->credits_requested == 0) {
 333                 log_rdma_event(ERR, "error: credits_requested==0\n");
 334                 return false;
 335         }
 336         info->receive_credit_target = le16_to_cpu(packet->credits_requested);
 337
 338         if (packet->credits_granted == 0) {
 339                 log_rdma_event(ERR, "error: credits_granted==0\n");
 340                 return false;
 341         }
 342         atomic_set(&info->send_credits, le16_to_cpu(packet->credits_granted));
 343
 344         atomic_set(&info->receive_credits, 0);
 345
 346         if (le32_to_cpu(packet->preferred_send_size) > info->max_receive_size) {
 347                 log_rdma_event(ERR, "error: preferred_send_size=%d\n",
 348                         le32_to_cpu(packet->preferred_send_size));
 349                 return false;
 350         }
 351         info->max_receive_size = le32_to_cpu(packet->preferred_send_size);
 352
 353         if (le32_to_cpu(packet->max_receive_size) < SMBD_MIN_RECEIVE_SIZE) {
 354                 log_rdma_event(ERR, "error: max_receive_size=%d\n",
 355                         le32_to_cpu(packet->max_receive_size));
 356                 return false;
 357         }
 358         info->max_send_size = min_t(int, info->max_send_size,
 359                                         le32_to_cpu(packet->max_receive_size));
 360
 361         if (le32_to_cpu(packet->max_fragmented_size) <
 362                         SMBD_MIN_FRAGMENTED_SIZE) {
 363                 log_rdma_event(ERR, "error: max_fragmented_size=%d\n",
 364                         le32_to_cpu(packet->max_fragmented_size));
 365                 return false;
 366         }
 367         info->max_fragmented_send_size =
 368                 le32_to_cpu(packet->max_fragmented_size);
 369         info->rdma_readwrite_threshold =
 370                 rdma_readwrite_threshold > info->max_fragmented_send_size ?
 371                 info->max_fragmented_send_size :
 372                 rdma_readwrite_threshold;
 373
 374
 375         info->max_readwrite_size = min_t(u32,
 376                         le32_to_cpu(packet->max_readwrite_size),
 377                         info->max_frmr_depth * PAGE_SIZE);
 378         info->max_frmr_depth = info->max_readwrite_size / PAGE_SIZE;
 379
 380         return true;
 381 }
 382
 383 static void smbd_post_send_credits(struct work_struct *work)
 384 {
 385         int ret = 0;
 386         int use_receive_queue = 1;
 387         int rc;
 388         struct smbd_response *response;
 389         struct smbd_connection *info =
 390                 container_of(work, struct smbd_connection,
 391                         post_send_credits_work);
 392
 393         if (info->transport_status != SMBD_CONNECTED) {
 394                 wake_up(&info->wait_receive_queues);
 395                 return;
 396         }
 397
 398         if (info->receive_credit_target >
 399                 atomic_read(&info->receive_credits)) {
 400                 while (true) {
 401                         if (use_receive_queue)
 402                                 response = get_receive_buffer(info);
 403                         else
 404                                 response = get_empty_queue_buffer(info);
 405                         if (!response) {
 406                                 /* now switch to emtpy packet queue */
 407                                 if (use_receive_queue) {
 408                                         use_receive_queue = 0;
 409                                         continue;
 410                                 } else
 411                                         break;
 412                         }
 413
 414                         response->type = SMBD_TRANSFER_DATA;
 415                         response->first_segment = false;
 416                         rc = smbd_post_recv(info, response);
 417                         if (rc) {
 418                                 log_rdma_recv(ERR,
 419                                         "post_recv failed rc=%d\n", rc);
 420                                 put_receive_buffer(info, response);
 421                                 break;
 422                         }
 423
 424                         ret++;
 425                 }
 426         }
 427
 428         spin_lock(&info->lock_new_credits_offered);
 429         info->new_credits_offered += ret;
 430         spin_unlock(&info->lock_new_credits_offered);
 431
 432         /* Promptly send an immediate packet as defined in [MS-SMBD] 3.1.1.1 */
 433         info->send_immediate = true;
 434         if (atomic_read(&info->receive_credits) <
 435                 info->receive_credit_target - 1) {
 436                 if (info->keep_alive_requested == KEEP_ALIVE_PENDING ||
 437                     info->send_immediate) {
 438                         log_keep_alive(INFO, "send an empty message\n");
 439                         smbd_post_send_empty(info);
 440                 }
 441         }
 442 }
 443
 444 /* Called from softirq, when recv is done */
 445 static void recv_done(struct ib_cq *cq, struct ib_wc *wc)
 446 {
 447         struct smbd_data_transfer *data_transfer;
 448         struct smbd_response *response =
 449                 container_of(wc->wr_cqe, struct smbd_response, cqe);
 450         struct smbd_connection *info = response->info;
 451         int data_length = 0;
 452
 453         log_rdma_recv(INFO, "response=%p type=%d wc status=%d wc opcode %d "
 454                       "byte_len=%d pkey_index=%x\n",
 455                 response, response->type, wc->status, wc->opcode,
 456                 wc->byte_len, wc->pkey_index);
 457
 458         if (wc->status != IB_WC_SUCCESS || wc->opcode != IB_WC_RECV) {
 459                 log_rdma_recv(INFO, "wc->status=%d opcode=%d\n",
 460                         wc->status, wc->opcode);
 461                 smbd_disconnect_rdma_connection(info);
 462                 goto error;
 463         }
 464
 465         ib_dma_sync_single_for_cpu(
 466                 wc->qp->device,
 467                 response->sge.addr,
 468                 response->sge.length,
 469                 DMA_FROM_DEVICE);
 470
 471         switch (response->type) {
 472         /* SMBD negotiation response */
 473         case SMBD_NEGOTIATE_RESP:
 474                 dump_smbd_negotiate_resp(smbd_response_payload(response));
 475                 info->full_packet_received = true;
 476                 info->negotiate_done =
 477                         process_negotiation_response(response, wc->byte_len);
 478                 complete(&info->negotiate_completion);
 479                 break;
 480
 481         /* SMBD data transfer packet */
 482         case SMBD_TRANSFER_DATA:
 483                 data_transfer = smbd_response_payload(response);
 484                 data_length = le32_to_cpu(data_transfer->data_length);
 485
 486                 /*
 487                  * If this is a packet with data playload place the data in
 488                  * reassembly queue and wake up the reading thread
 489                  */
 490                 if (data_length) {
 491                         if (info->full_packet_received)
 492                                 response->first_segment = true;
 493
 494                         if (le32_to_cpu(data_transfer->remaining_data_length))
 495                                 info->full_packet_received = false;
 496                         else
 497                                 info->full_packet_received = true;
 498
 499                         enqueue_reassembly(
 500                                 info,
 501                                 response,
 502                                 data_length);
 503                 } else
 504                         put_empty_packet(info, response);
 505
 506                 if (data_length)
 507                         wake_up_interruptible(&info->wait_reassembly_queue);
 508
 509                 atomic_dec(&info->receive_credits);
 510                 info->receive_credit_target =
 511                         le16_to_cpu(data_transfer->credits_requested);
 512                 if (le16_to_cpu(data_transfer->credits_granted)) {
 513                         atomic_add(le16_to_cpu(data_transfer->credits_granted),
 514                                 &info->send_credits);
 515                         /*
 516                          * We have new send credits granted from remote peer
 517                          * If any sender is waiting for credits, unblock it
 518                          */
 519                         wake_up_interruptible(&info->wait_send_queue);
 520                 }
 521
 522                 log_incoming(INFO, "data flags %d data_offset %d "
 523                         "data_length %d remaining_data_length %d\n",
 524                         le16_to_cpu(data_transfer->flags),
 525                         le32_to_cpu(data_transfer->data_offset),
 526                         le32_to_cpu(data_transfer->data_length),
 527                         le32_to_cpu(data_transfer->remaining_data_length));
 528
 529                 /* Send a KEEP_ALIVE response right away if requested */
 530                 info->keep_alive_requested = KEEP_ALIVE_NONE;
 531                 if (le16_to_cpu(data_transfer->flags) &
 532                                 SMB_DIRECT_RESPONSE_REQUESTED) {
 533                         info->keep_alive_requested = KEEP_ALIVE_PENDING;
 534                 }
 535
 536                 return;
 537
 538         default:
 539                 log_rdma_recv(ERR,
 540                         "unexpected response type=%d\n", response->type);
 541         }
 542
 543 error:
 544         put_receive_buffer(info, response);
 545 }
 546
 547 static struct rdma_cm_id *smbd_create_id(
 548                 struct smbd_connection *info,
 549                 struct sockaddr *dstaddr, int port)
 550 {
 551         struct rdma_cm_id *id;
 552         int rc;
 553         __be16 *sport;
 554
 555         id = rdma_create_id(&init_net, smbd_conn_upcall, info,
 556                 RDMA_PS_TCP, IB_QPT_RC);
 557         if (IS_ERR(id)) {
 558                 rc = PTR_ERR(id);
 559                 log_rdma_event(ERR, "rdma_create_id() failed %i\n", rc);
 560                 return id;
 561         }
 562
 563         if (dstaddr->sa_family == AF_INET6)
 564                 sport = &((struct sockaddr_in6 *)dstaddr)->sin6_port;
 565         else
 566                 sport = &((struct sockaddr_in *)dstaddr)->sin_port;
 567
 568         *sport = htons(port);
 569
 570         init_completion(&info->ri_done);
 571         info->ri_rc = -ETIMEDOUT;
 572
 573         rc = rdma_resolve_addr(id, NULL, (struct sockaddr *)dstaddr,
 574                 RDMA_RESOLVE_TIMEOUT);
 575         if (rc) {
 576                 log_rdma_event(ERR, "rdma_resolve_addr() failed %i\n", rc);
 577                 goto out;
 578         }
 579         wait_for_completion_interruptible_timeout(
 580                 &info->ri_done, msecs_to_jiffies(RDMA_RESOLVE_TIMEOUT));
 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         wait_for_completion_interruptible_timeout(
 594                 &info->ri_done, msecs_to_jiffies(RDMA_RESOLVE_TIMEOUT));
 595         rc = info->ri_rc;
 596         if (rc) {
 597                 log_rdma_event(ERR, "rdma_resolve_route() completed %i\n", rc);
 598                 goto out;
 599         }
 600
 601         return id;
 602
 603 out:
 604         rdma_destroy_id(id);
 605         return ERR_PTR(rc);
 606 }
 607
 608 /*
 609  * Test if FRWR (Fast Registration Work Requests) is supported on the device
 610  * This implementation requries FRWR on RDMA read/write
 611  * return value: true if it is supported
 612  */
 613 static bool frwr_is_supported(struct ib_device_attr *attrs)
 614 {
 615         if (!(attrs->device_cap_flags & IB_DEVICE_MEM_MGT_EXTENSIONS))
 616                 return false;
 617         if (attrs->max_fast_reg_page_list_len == 0)
 618                 return false;
 619         return true;
 620 }
 621
 622 static int smbd_ia_open(
 623                 struct smbd_connection *info,
 624                 struct sockaddr *dstaddr, int port)
 625 {
 626         int rc;
 627
 628         info->id = smbd_create_id(info, dstaddr, port);
 629         if (IS_ERR(info->id)) {
 630                 rc = PTR_ERR(info->id);
 631                 goto out1;
 632         }
 633
 634         if (!frwr_is_supported(&info->id->device->attrs)) {
 635                 log_rdma_event(ERR,
 636                         "Fast Registration Work Requests "
 637                         "(FRWR) is not supported\n");
 638                 log_rdma_event(ERR,
 639                         "Device capability flags = %llx "
 640                         "max_fast_reg_page_list_len = %u\n",
 641                         info->id->device->attrs.device_cap_flags,
 642                         info->id->device->attrs.max_fast_reg_page_list_len);
 643                 rc = -EPROTONOSUPPORT;
 644                 goto out2;
 645         }
 646         info->max_frmr_depth = min_t(int,
 647                 smbd_max_frmr_depth,
 648                 info->id->device->attrs.max_fast_reg_page_list_len);
 649         info->mr_type = IB_MR_TYPE_MEM_REG;
 650         if (info->id->device->attrs.device_cap_flags & IB_DEVICE_SG_GAPS_REG)
 651                 info->mr_type = IB_MR_TYPE_SG_GAPS;
 652
 653         info->pd = ib_alloc_pd(info->id->device, 0);
 654         if (IS_ERR(info->pd)) {
 655                 rc = PTR_ERR(info->pd);
 656                 log_rdma_event(ERR, "ib_alloc_pd() returned %d\n", rc);
 657                 goto out2;
 658         }
 659
 660         return 0;
 661
 662 out2:
 663         rdma_destroy_id(info->id);
 664         info->id = NULL;
 665
 666 out1:
 667         return rc;
 668 }
 669
 670 /*
 671  * Send a negotiation request message to the peer
 672  * The negotiation procedure is in [MS-SMBD] 3.1.5.2 and 3.1.5.3
 673  * After negotiation, the transport is connected and ready for
 674  * carrying upper layer SMB payload
 675  */
 676 static int smbd_post_send_negotiate_req(struct smbd_connection *info)
 677 {
 678         struct ib_send_wr send_wr;
 679         int rc = -ENOMEM;
 680         struct smbd_request *request;
 681         struct smbd_negotiate_req *packet;
 682
 683         request = mempool_alloc(info->request_mempool, GFP_KERNEL);
 684         if (!request)
 685                 return rc;
 686
 687         request->info = info;
 688
 689         packet = smbd_request_payload(request);
 690         packet->min_version = cpu_to_le16(SMBD_V1);
 691         packet->max_version = cpu_to_le16(SMBD_V1);
 692         packet->reserved = 0;
 693         packet->credits_requested = cpu_to_le16(info->send_credit_target);
 694         packet->preferred_send_size = cpu_to_le32(info->max_send_size);
 695         packet->max_receive_size = cpu_to_le32(info->max_receive_size);
 696         packet->max_fragmented_size =
 697                 cpu_to_le32(info->max_fragmented_recv_size);
 698
 699         request->num_sge = 1;
 700         request->sge[0].addr = ib_dma_map_single(
 701                                 info->id->device, (void *)packet,
 702                                 sizeof(*packet), DMA_TO_DEVICE);
 703         if (ib_dma_mapping_error(info->id->device, request->sge[0].addr)) {
 704                 rc = -EIO;
 705                 goto dma_mapping_failed;
 706         }
 707
 708         request->sge[0].length = sizeof(*packet);
 709         request->sge[0].lkey = info->pd->local_dma_lkey;
 710
 711         ib_dma_sync_single_for_device(
 712                 info->id->device, request->sge[0].addr,
 713                 request->sge[0].length, DMA_TO_DEVICE);
 714
 715         request->cqe.done = send_done;
 716
 717         send_wr.next = NULL;
 718         send_wr.wr_cqe = &request->cqe;
 719         send_wr.sg_list = request->sge;
 720         send_wr.num_sge = request->num_sge;
 721         send_wr.opcode = IB_WR_SEND;
 722         send_wr.send_flags = IB_SEND_SIGNALED;
 723
 724         log_rdma_send(INFO, "sge addr=%llx length=%x lkey=%x\n",
 725                 request->sge[0].addr,
 726                 request->sge[0].length, request->sge[0].lkey);
 727
 728         atomic_inc(&info->send_pending);
 729         rc = ib_post_send(info->id->qp, &send_wr, NULL);
 730         if (!rc)
 731                 return 0;
 732
 733         /* if we reach here, post send failed */
 734         log_rdma_send(ERR, "ib_post_send failed rc=%d\n", rc);
 735         atomic_dec(&info->send_pending);
 736         ib_dma_unmap_single(info->id->device, request->sge[0].addr,
 737                 request->sge[0].length, DMA_TO_DEVICE);
 738
 739         smbd_disconnect_rdma_connection(info);
 740
 741 dma_mapping_failed:
 742         mempool_free(request, info->request_mempool);
 743         return rc;
 744 }
 745
 746 /*
 747  * Extend the credits to remote peer
 748  * This implements [MS-SMBD] 3.1.5.9
 749  * The idea is that we should extend credits to remote peer as quickly as
 750  * it's allowed, to maintain data flow. We allocate as much receive
 751  * buffer as possible, and extend the receive credits to remote peer
 752  * return value: the new credtis being granted.
 753  */
 754 static int manage_credits_prior_sending(struct smbd_connection *info)
 755 {
 756         int new_credits;
 757
 758         spin_lock(&info->lock_new_credits_offered);
 759         new_credits = info->new_credits_offered;
 760         info->new_credits_offered = 0;
 761         spin_unlock(&info->lock_new_credits_offered);
 762
 763         return new_credits;
 764 }
 765
 766 /*
 767  * Check if we need to send a KEEP_ALIVE message
 768  * The idle connection timer triggers a KEEP_ALIVE message when expires
 769  * SMB_DIRECT_RESPONSE_REQUESTED is set in the message flag to have peer send
 770  * back a response.
 771  * return value:
 772  * 1 if SMB_DIRECT_RESPONSE_REQUESTED needs to be set
 773  * 0: otherwise
 774  */
 775 static int manage_keep_alive_before_sending(struct smbd_connection *info)
 776 {
 777         if (info->keep_alive_requested == KEEP_ALIVE_PENDING) {
 778                 info->keep_alive_requested = KEEP_ALIVE_SENT;
 779                 return 1;
 780         }
 781         return 0;
 782 }
 783
 784 /* Post the send request */
 785 static int smbd_post_send(struct smbd_connection *info,
 786                 struct smbd_request *request)
 787 {
 788         struct ib_send_wr send_wr;
 789         int rc, i;
 790
 791         for (i = 0; i < request->num_sge; i++) {
 792                 log_rdma_send(INFO,
 793                         "rdma_request sge[%d] addr=%llu length=%u\n",
 794                         i, request->sge[i].addr, request->sge[i].length);
 795                 ib_dma_sync_single_for_device(
 796                         info->id->device,
 797                         request->sge[i].addr,
 798                         request->sge[i].length,
 799                         DMA_TO_DEVICE);
 800         }
 801
 802         request->cqe.done = send_done;
 803
 804         send_wr.next = NULL;
 805         send_wr.wr_cqe = &request->cqe;
 806         send_wr.sg_list = request->sge;
 807         send_wr.num_sge = request->num_sge;
 808         send_wr.opcode = IB_WR_SEND;
 809         send_wr.send_flags = IB_SEND_SIGNALED;
 810
 811         rc = ib_post_send(info->id->qp, &send_wr, NULL);
 812         if (rc) {
 813                 log_rdma_send(ERR, "ib_post_send failed rc=%d\n", rc);
 814                 smbd_disconnect_rdma_connection(info);
 815                 rc = -EAGAIN;
 816         } else
 817                 /* Reset timer for idle connection after packet is sent */
 818                 mod_delayed_work(info->workqueue, &info->idle_timer_work,
 819                         info->keep_alive_interval*HZ);
 820
 821         return rc;
 822 }
 823
 824 static int smbd_post_send_sgl(struct smbd_connection *info,
 825         struct scatterlist *sgl, int data_length, int remaining_data_length)
 826 {
 827         int num_sgs;
 828         int i, rc;
 829         int header_length;
 830         struct smbd_request *request;
 831         struct smbd_data_transfer *packet;
 832         int new_credits;
 833         struct scatterlist *sg;
 834
 835 wait_credit:
 836         /* Wait for send credits. A SMBD packet needs one credit */
 837         rc = wait_event_interruptible(info->wait_send_queue,
 838                 atomic_read(&info->send_credits) > 0 ||
 839                 info->transport_status != SMBD_CONNECTED);
 840         if (rc)
 841                 goto err_wait_credit;
 842
 843         if (info->transport_status != SMBD_CONNECTED) {
 844                 log_outgoing(ERR, "disconnected not sending on wait_credit\n");
 845                 rc = -EAGAIN;
 846                 goto err_wait_credit;
 847         }
 848         if (unlikely(atomic_dec_return(&info->send_credits) < 0)) {
 849                 atomic_inc(&info->send_credits);
 850                 goto wait_credit;
 851         }
 852
 853 wait_send_queue:
 854         wait_event(info->wait_post_send,
 855                 atomic_read(&info->send_pending) < info->send_credit_target ||
 856                 info->transport_status != SMBD_CONNECTED);
 857
 858         if (info->transport_status != SMBD_CONNECTED) {
 859                 log_outgoing(ERR, "disconnected not sending on wait_send_queue\n");
 860                 rc = -EAGAIN;
 861                 goto err_wait_send_queue;
 862         }
 863
 864         if (unlikely(atomic_inc_return(&info->send_pending) >
 865                                 info->send_credit_target)) {
 866                 atomic_dec(&info->send_pending);
 867                 goto wait_send_queue;
 868         }
 869
 870         request = mempool_alloc(info->request_mempool, GFP_KERNEL);
 871         if (!request) {
 872                 rc = -ENOMEM;
 873                 goto err_alloc;
 874         }
 875
 876         request->info = info;
 877
 878         /* Fill in the packet header */
 879         packet = smbd_request_payload(request);
 880         packet->credits_requested = cpu_to_le16(info->send_credit_target);
 881
 882         new_credits = manage_credits_prior_sending(info);
 883         atomic_add(new_credits, &info->receive_credits);
 884         packet->credits_granted = cpu_to_le16(new_credits);
 885
 886         info->send_immediate = false;
 887
 888         packet->flags = 0;
 889         if (manage_keep_alive_before_sending(info))
 890                 packet->flags |= cpu_to_le16(SMB_DIRECT_RESPONSE_REQUESTED);
 891
 892         packet->reserved = 0;
 893         if (!data_length)
 894                 packet->data_offset = 0;
 895         else
 896                 packet->data_offset = cpu_to_le32(24);
 897         packet->data_length = cpu_to_le32(data_length);
 898         packet->remaining_data_length = cpu_to_le32(remaining_data_length);
 899         packet->padding = 0;
 900
 901         log_outgoing(INFO, "credits_requested=%d credits_granted=%d "
 902                 "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,
1082                 "smbd_post_recv rc=%d iov.addr=%llx iov.length=%x "
1083                 "iov.lkey=%x\n",
1084                 rc, response->sge.addr,
1085                 response->sge.length, response->sge.lkey);
1086         if (rc)
1087                 return rc;
1088
1089         init_completion(&info->negotiate_completion);
1090         info->negotiate_done = false;
1091         rc = smbd_post_send_negotiate_req(info);
1092         if (rc)
1093                 return rc;
1094
1095         rc = wait_for_completion_interruptible_timeout(
1096                 &info->negotiate_completion, SMBD_NEGOTIATE_TIMEOUT * HZ);
1097         log_rdma_event(INFO, "wait_for_completion_timeout rc=%d\n", rc);
1098
1099         if (info->negotiate_done)
1100                 return 0;
1101
1102         if (rc == 0)
1103                 rc = -ETIMEDOUT;
1104         else if (rc == -ERESTARTSYS)
1105                 rc = -EINTR;
1106         else
1107                 rc = -ENOTCONN;
1108
1109         return rc;
1110 }
1111
1112 static void put_empty_packet(
1113                 struct smbd_connection *info, struct smbd_response *response)
1114 {
1115         spin_lock(&info->empty_packet_queue_lock);
1116         list_add_tail(&response->list, &info->empty_packet_queue);
1117         info->count_empty_packet_queue++;
1118         spin_unlock(&info->empty_packet_queue_lock);
1119
1120         queue_work(info->workqueue, &info->post_send_credits_work);
1121 }
1122
1123 /*
1124  * Implement Connection.FragmentReassemblyBuffer defined in [MS-SMBD] 3.1.1.1
1125  * This is a queue for reassembling upper layer payload and present to upper
1126  * layer. All the inncoming payload go to the reassembly queue, regardless of
1127  * if reassembly is required. The uuper layer code reads from the queue for all
1128  * incoming payloads.
1129  * Put a received packet to the reassembly queue
1130  * response: the packet received
1131  * data_length: the size of payload in this packet
1132  */
1133 static void enqueue_reassembly(
1134         struct smbd_connection *info,
1135         struct smbd_response *response,
1136         int data_length)
1137 {
1138         spin_lock(&info->reassembly_queue_lock);
1139         list_add_tail(&response->list, &info->reassembly_queue);
1140         info->reassembly_queue_length++;
1141         /*
1142          * Make sure reassembly_data_length is updated after list and
1143          * reassembly_queue_length are updated. On the dequeue side
1144          * reassembly_data_length is checked without a lock to determine
1145          * if reassembly_queue_length and list is up to date
1146          */
1147         virt_wmb();
1148         info->reassembly_data_length += data_length;
1149         spin_unlock(&info->reassembly_queue_lock);
1150         info->count_reassembly_queue++;
1151         info->count_enqueue_reassembly_queue++;
1152 }
1153
1154 /*
1155  * Get the first entry at the front of reassembly queue
1156  * Caller is responsible for locking
1157  * return value: the first entry if any, NULL if queue is empty
1158  */
1159 static struct smbd_response *_get_first_reassembly(struct smbd_connection *info)
1160 {
1161         struct smbd_response *ret = NULL;
1162
1163         if (!list_empty(&info->reassembly_queue)) {
1164                 ret = list_first_entry(
1165                         &info->reassembly_queue,
1166                         struct smbd_response, list);
1167         }
1168         return ret;
1169 }
1170
1171 static struct smbd_response *get_empty_queue_buffer(
1172                 struct smbd_connection *info)
1173 {
1174         struct smbd_response *ret = NULL;
1175         unsigned long flags;
1176
1177         spin_lock_irqsave(&info->empty_packet_queue_lock, flags);
1178         if (!list_empty(&info->empty_packet_queue)) {
1179                 ret = list_first_entry(
1180                         &info->empty_packet_queue,
1181                         struct smbd_response, list);
1182                 list_del(&ret->list);
1183                 info->count_empty_packet_queue--;
1184         }
1185         spin_unlock_irqrestore(&info->empty_packet_queue_lock, flags);
1186
1187         return ret;
1188 }
1189
1190 /*
1191  * Get a receive buffer
1192  * For each remote send, we need to post a receive. The receive buffers are
1193  * pre-allocated in advance.
1194  * return value: the receive buffer, NULL if none is available
1195  */
1196 static struct smbd_response *get_receive_buffer(struct smbd_connection *info)
1197 {
1198         struct smbd_response *ret = NULL;
1199         unsigned long flags;
1200
1201         spin_lock_irqsave(&info->receive_queue_lock, flags);
1202         if (!list_empty(&info->receive_queue)) {
1203                 ret = list_first_entry(
1204                         &info->receive_queue,
1205                         struct smbd_response, list);
1206                 list_del(&ret->list);
1207                 info->count_receive_queue--;
1208                 info->count_get_receive_buffer++;
1209         }
1210         spin_unlock_irqrestore(&info->receive_queue_lock, flags);
1211
1212         return ret;
1213 }
1214
1215 /*
1216  * Return a receive buffer
1217  * Upon returning of a receive buffer, we can post new receive and extend
1218  * more receive credits to remote peer. This is done immediately after a
1219  * receive buffer is returned.
1220  */
1221 static void put_receive_buffer(
1222         struct smbd_connection *info, struct smbd_response *response)
1223 {
1224         unsigned long flags;
1225
1226         ib_dma_unmap_single(info->id->device, response->sge.addr,
1227                 response->sge.length, DMA_FROM_DEVICE);
1228
1229         spin_lock_irqsave(&info->receive_queue_lock, flags);
1230         list_add_tail(&response->list, &info->receive_queue);
1231         info->count_receive_queue++;
1232         info->count_put_receive_buffer++;
1233         spin_unlock_irqrestore(&info->receive_queue_lock, flags);
1234
1235         queue_work(info->workqueue, &info->post_send_credits_work);
1236 }
1237
1238 /* Preallocate all receive buffer on transport establishment */
1239 static int allocate_receive_buffers(struct smbd_connection *info, int num_buf)
1240 {
1241         int i;
1242         struct smbd_response *response;
1243
1244         INIT_LIST_HEAD(&info->reassembly_queue);
1245         spin_lock_init(&info->reassembly_queue_lock);
1246         info->reassembly_data_length = 0;
1247         info->reassembly_queue_length = 0;
1248
1249         INIT_LIST_HEAD(&info->receive_queue);
1250         spin_lock_init(&info->receive_queue_lock);
1251         info->count_receive_queue = 0;
1252
1253         INIT_LIST_HEAD(&info->empty_packet_queue);
1254         spin_lock_init(&info->empty_packet_queue_lock);
1255         info->count_empty_packet_queue = 0;
1256
1257         init_waitqueue_head(&info->wait_receive_queues);
1258
1259         for (i = 0; i < num_buf; i++) {
1260                 response = mempool_alloc(info->response_mempool, GFP_KERNEL);
1261                 if (!response)
1262                         goto allocate_failed;
1263
1264                 response->info = info;
1265                 list_add_tail(&response->list, &info->receive_queue);
1266                 info->count_receive_queue++;
1267         }
1268
1269         return 0;
1270
1271 allocate_failed:
1272         while (!list_empty(&info->receive_queue)) {
1273                 response = list_first_entry(
1274                                 &info->receive_queue,
1275                                 struct smbd_response, list);
1276                 list_del(&response->list);
1277                 info->count_receive_queue--;
1278
1279                 mempool_free(response, info->response_mempool);
1280         }
1281         return -ENOMEM;
1282 }
1283
1284 static void destroy_receive_buffers(struct smbd_connection *info)
1285 {
1286         struct smbd_response *response;
1287
1288         while ((response = get_receive_buffer(info)))
1289                 mempool_free(response, info->response_mempool);
1290
1291         while ((response = get_empty_queue_buffer(info)))
1292                 mempool_free(response, info->response_mempool);
1293 }
1294
1295 /* Implement idle connection timer [MS-SMBD] 3.1.6.2 */
1296 static void idle_connection_timer(struct work_struct *work)
1297 {
1298         struct smbd_connection *info = container_of(
1299                                         work, struct smbd_connection,
1300                                         idle_timer_work.work);
1301
1302         if (info->keep_alive_requested != KEEP_ALIVE_NONE) {
1303                 log_keep_alive(ERR,
1304                         "error status info->keep_alive_requested=%d\n",
1305                         info->keep_alive_requested);
1306                 smbd_disconnect_rdma_connection(info);
1307                 return;
1308         }
1309
1310         log_keep_alive(INFO, "about to send an empty idle message\n");
1311         smbd_post_send_empty(info);
1312
1313         /* Setup the next idle timeout work */
1314         queue_delayed_work(info->workqueue, &info->idle_timer_work,
1315                         info->keep_alive_interval*HZ);
1316 }
1317
1318 /*
1319  * Destroy the transport and related RDMA and memory resources
1320  * Need to go through all the pending counters and make sure on one is using
1321  * the transport while it is destroyed
1322  */
1323 void smbd_destroy(struct TCP_Server_Info *server)
1324 {
1325         struct smbd_connection *info = server->smbd_conn;
1326         struct smbd_response *response;
1327         unsigned long flags;
1328
1329         if (!info) {
1330                 log_rdma_event(INFO, "rdma session already destroyed\n");
1331                 return;
1332         }
1333
1334         log_rdma_event(INFO, "destroying rdma session\n");
1335         if (info->transport_status != SMBD_DISCONNECTED) {
1336                 rdma_disconnect(server->smbd_conn->id);
1337                 log_rdma_event(INFO, "wait for transport being disconnected\n");
1338                 wait_event_interruptible(
1339                         info->disconn_wait,
1340                         info->transport_status == SMBD_DISCONNECTED);
1341         }
1342
1343         log_rdma_event(INFO, "destroying qp\n");
1344         ib_drain_qp(info->id->qp);
1345         rdma_destroy_qp(info->id);
1346
1347         log_rdma_event(INFO, "cancelling idle timer\n");
1348         cancel_delayed_work_sync(&info->idle_timer_work);
1349
1350         log_rdma_event(INFO, "wait for all send posted to IB to finish\n");
1351         wait_event(info->wait_send_pending,
1352                 atomic_read(&info->send_pending) == 0);
1353
1354         /* It's not posssible for upper layer to get to reassembly */
1355         log_rdma_event(INFO, "drain the reassembly queue\n");
1356         do {
1357                 spin_lock_irqsave(&info->reassembly_queue_lock, flags);
1358                 response = _get_first_reassembly(info);
1359                 if (response) {
1360                         list_del(&response->list);
1361                         spin_unlock_irqrestore(
1362                                 &info->reassembly_queue_lock, flags);
1363                         put_receive_buffer(info, response);
1364                 } else
1365                         spin_unlock_irqrestore(
1366                                 &info->reassembly_queue_lock, flags);
1367         } while (response);
1368         info->reassembly_data_length = 0;
1369
1370         log_rdma_event(INFO, "free receive buffers\n");
1371         wait_event(info->wait_receive_queues,
1372                 info->count_receive_queue + info->count_empty_packet_queue
1373                         == info->receive_credit_max);
1374         destroy_receive_buffers(info);
1375
1376         /*
1377          * For performance reasons, memory registration and deregistration
1378          * are not locked by srv_mutex. It is possible some processes are
1379          * blocked on transport srv_mutex while holding memory registration.
1380          * Release the transport srv_mutex to allow them to hit the failure
1381          * path when sending data, and then release memory registartions.
1382          */
1383         log_rdma_event(INFO, "freeing mr list\n");
1384         wake_up_interruptible_all(&info->wait_mr);
1385         while (atomic_read(&info->mr_used_count)) {
1386                 mutex_unlock(&server->srv_mutex);
1387                 msleep(1000);
1388                 mutex_lock(&server->srv_mutex);
1389         }
1390         destroy_mr_list(info);
1391
1392         ib_free_cq(info->send_cq);
1393         ib_free_cq(info->recv_cq);
1394         ib_dealloc_pd(info->pd);
1395         rdma_destroy_id(info->id);
1396
1397         /* free mempools */
1398         mempool_destroy(info->request_mempool);
1399         kmem_cache_destroy(info->request_cache);
1400
1401         mempool_destroy(info->response_mempool);
1402         kmem_cache_destroy(info->response_cache);
1403
1404         info->transport_status = SMBD_DESTROYED;
1405
1406         destroy_workqueue(info->workqueue);
1407         log_rdma_event(INFO,  "rdma session destroyed\n");
1408         kfree(info);
1409 }
1410
1411 /*
1412  * Reconnect this SMBD connection, called from upper layer
1413  * return value: 0 on success, or actual error code
1414  */
1415 int smbd_reconnect(struct TCP_Server_Info *server)
1416 {
1417         log_rdma_event(INFO, "reconnecting rdma session\n");
1418
1419         if (!server->smbd_conn) {
1420                 log_rdma_event(INFO, "rdma session already destroyed\n");
1421                 goto create_conn;
1422         }
1423
1424         /*
1425          * This is possible if transport is disconnected and we haven't received
1426          * notification from RDMA, but upper layer has detected timeout
1427          */
1428         if (server->smbd_conn->transport_status == SMBD_CONNECTED) {
1429                 log_rdma_event(INFO, "disconnecting transport\n");
1430                 smbd_destroy(server);
1431         }
1432
1433 create_conn:
1434         log_rdma_event(INFO, "creating rdma session\n");
1435         server->smbd_conn = smbd_get_connection(
1436                 server, (struct sockaddr *) &server->dstaddr);
1437
1438         if (server->smbd_conn)
1439                 cifs_dbg(VFS, "RDMA transport re-established\n");
1440
1441         return server->smbd_conn ? 0 : -ENOENT;
1442 }
1443
1444 static void destroy_caches_and_workqueue(struct smbd_connection *info)
1445 {
1446         destroy_receive_buffers(info);
1447         destroy_workqueue(info->workqueue);
1448         mempool_destroy(info->response_mempool);
1449         kmem_cache_destroy(info->response_cache);
1450         mempool_destroy(info->request_mempool);
1451         kmem_cache_destroy(info->request_cache);
1452 }
1453
1454 #define MAX_NAME_LEN    80
1455 static int allocate_caches_and_workqueue(struct smbd_connection *info)
1456 {
1457         char name[MAX_NAME_LEN];
1458         int rc;
1459
1460         scnprintf(name, MAX_NAME_LEN, "smbd_request_%p", info);
1461         info->request_cache =
1462                 kmem_cache_create(
1463                         name,
1464                         sizeof(struct smbd_request) +
1465                                 sizeof(struct smbd_data_transfer),
1466                         0, SLAB_HWCACHE_ALIGN, NULL);
1467         if (!info->request_cache)
1468                 return -ENOMEM;
1469
1470         info->request_mempool =
1471                 mempool_create(info->send_credit_target, mempool_alloc_slab,
1472                         mempool_free_slab, info->request_cache);
1473         if (!info->request_mempool)
1474                 goto out1;
1475
1476         scnprintf(name, MAX_NAME_LEN, "smbd_response_%p", info);
1477         info->response_cache =
1478                 kmem_cache_create(
1479                         name,
1480                         sizeof(struct smbd_response) +
1481                                 info->max_receive_size,
1482                         0, SLAB_HWCACHE_ALIGN, NULL);
1483         if (!info->response_cache)
1484                 goto out2;
1485
1486         info->response_mempool =
1487                 mempool_create(info->receive_credit_max, mempool_alloc_slab,
1488                        mempool_free_slab, info->response_cache);
1489         if (!info->response_mempool)
1490                 goto out3;
1491
1492         scnprintf(name, MAX_NAME_LEN, "smbd_%p", info);
1493         info->workqueue = create_workqueue(name);
1494         if (!info->workqueue)
1495                 goto out4;
1496
1497         rc = allocate_receive_buffers(info, info->receive_credit_max);
1498         if (rc) {
1499                 log_rdma_event(ERR, "failed to allocate receive buffers\n");
1500                 goto out5;
1501         }
1502
1503         return 0;
1504
1505 out5:
1506         destroy_workqueue(info->workqueue);
1507 out4:
1508         mempool_destroy(info->response_mempool);
1509 out3:
1510         kmem_cache_destroy(info->response_cache);
1511 out2:
1512         mempool_destroy(info->request_mempool);
1513 out1:
1514         kmem_cache_destroy(info->request_cache);
1515         return -ENOMEM;
1516 }
1517
1518 /* Create a SMBD connection, called by upper layer */
1519 static struct smbd_connection *_smbd_get_connection(
1520         struct TCP_Server_Info *server, struct sockaddr *dstaddr, int port)
1521 {
1522         int rc;
1523         struct smbd_connection *info;
1524         struct rdma_conn_param conn_param;
1525         struct ib_qp_init_attr qp_attr;
1526         struct sockaddr_in *addr_in = (struct sockaddr_in *) dstaddr;
1527         struct ib_port_immutable port_immutable;
1528         u32 ird_ord_hdr[2];
1529
1530         info = kzalloc(sizeof(struct smbd_connection), GFP_KERNEL);
1531         if (!info)
1532                 return NULL;
1533
1534         info->transport_status = SMBD_CONNECTING;
1535         rc = smbd_ia_open(info, dstaddr, port);
1536         if (rc) {
1537                 log_rdma_event(INFO, "smbd_ia_open rc=%d\n", rc);
1538                 goto create_id_failed;
1539         }
1540
1541         if (smbd_send_credit_target > info->id->device->attrs.max_cqe ||
1542             smbd_send_credit_target > info->id->device->attrs.max_qp_wr) {
1543                 log_rdma_event(ERR,
1544                         "consider lowering send_credit_target = %d. "
1545                         "Possible CQE overrun, device "
1546                         "reporting max_cpe %d max_qp_wr %d\n",
1547                         smbd_send_credit_target,
1548                         info->id->device->attrs.max_cqe,
1549                         info->id->device->attrs.max_qp_wr);
1550                 goto config_failed;
1551         }
1552
1553         if (smbd_receive_credit_max > info->id->device->attrs.max_cqe ||
1554             smbd_receive_credit_max > info->id->device->attrs.max_qp_wr) {
1555                 log_rdma_event(ERR,
1556                         "consider lowering receive_credit_max = %d. "
1557                         "Possible CQE overrun, device "
1558                         "reporting max_cpe %d max_qp_wr %d\n",
1559                         smbd_receive_credit_max,
1560                         info->id->device->attrs.max_cqe,
1561                         info->id->device->attrs.max_qp_wr);
1562                 goto config_failed;
1563         }
1564
1565         info->receive_credit_max = smbd_receive_credit_max;
1566         info->send_credit_target = smbd_send_credit_target;
1567         info->max_send_size = smbd_max_send_size;
1568         info->max_fragmented_recv_size = smbd_max_fragmented_recv_size;
1569         info->max_receive_size = smbd_max_receive_size;
1570         info->keep_alive_interval = smbd_keep_alive_interval;
1571
1572         if (info->id->device->attrs.max_send_sge < SMBDIRECT_MAX_SGE) {
1573                 log_rdma_event(ERR,
1574                         "warning: device max_send_sge = %d too small\n",
1575                         info->id->device->attrs.max_send_sge);
1576                 log_rdma_event(ERR, "Queue Pair creation may fail\n");
1577         }
1578         if (info->id->device->attrs.max_recv_sge < SMBDIRECT_MAX_SGE) {
1579                 log_rdma_event(ERR,
1580                         "warning: device max_recv_sge = %d too small\n",
1581                         info->id->device->attrs.max_recv_sge);
1582                 log_rdma_event(ERR, "Queue Pair creation may fail\n");
1583         }
1584
1585         info->send_cq = NULL;
1586         info->recv_cq = NULL;
1587         info->send_cq =
1588                 ib_alloc_cq_any(info->id->device, info,
1589                                 info->send_credit_target, IB_POLL_SOFTIRQ);
1590         if (IS_ERR(info->send_cq)) {
1591                 info->send_cq = NULL;
1592                 goto alloc_cq_failed;
1593         }
1594
1595         info->recv_cq =
1596                 ib_alloc_cq_any(info->id->device, info,
1597                                 info->receive_credit_max, IB_POLL_SOFTIRQ);
1598         if (IS_ERR(info->recv_cq)) {
1599                 info->recv_cq = NULL;
1600                 goto alloc_cq_failed;
1601         }
1602
1603         memset(&qp_attr, 0, sizeof(qp_attr));
1604         qp_attr.event_handler = smbd_qp_async_error_upcall;
1605         qp_attr.qp_context = info;
1606         qp_attr.cap.max_send_wr = info->send_credit_target;
1607         qp_attr.cap.max_recv_wr = info->receive_credit_max;
1608         qp_attr.cap.max_send_sge = SMBDIRECT_MAX_SGE;
1609         qp_attr.cap.max_recv_sge = SMBDIRECT_MAX_SGE;
1610         qp_attr.cap.max_inline_data = 0;
1611         qp_attr.sq_sig_type = IB_SIGNAL_REQ_WR;
1612         qp_attr.qp_type = IB_QPT_RC;
1613         qp_attr.send_cq = info->send_cq;
1614         qp_attr.recv_cq = info->recv_cq;
1615         qp_attr.port_num = ~0;
1616
1617         rc = rdma_create_qp(info->id, info->pd, &qp_attr);
1618         if (rc) {
1619                 log_rdma_event(ERR, "rdma_create_qp failed %i\n", rc);
1620                 goto create_qp_failed;
1621         }
1622
1623         memset(&conn_param, 0, sizeof(conn_param));
1624         conn_param.initiator_depth = 0;
1625
1626         conn_param.responder_resources =
1627                 info->id->device->attrs.max_qp_rd_atom
1628                         < SMBD_CM_RESPONDER_RESOURCES ?
1629                 info->id->device->attrs.max_qp_rd_atom :
1630                 SMBD_CM_RESPONDER_RESOURCES;
1631         info->responder_resources = conn_param.responder_resources;
1632         log_rdma_mr(INFO, "responder_resources=%d\n",
1633                 info->responder_resources);
1634
1635         /* Need to send IRD/ORD in private data for iWARP */
1636         info->id->device->ops.get_port_immutable(
1637                 info->id->device, info->id->port_num, &port_immutable);
1638         if (port_immutable.core_cap_flags & RDMA_CORE_PORT_IWARP) {
1639                 ird_ord_hdr[0] = info->responder_resources;
1640                 ird_ord_hdr[1] = 1;
1641                 conn_param.private_data = ird_ord_hdr;
1642                 conn_param.private_data_len = sizeof(ird_ord_hdr);
1643         } else {
1644                 conn_param.private_data = NULL;
1645                 conn_param.private_data_len = 0;
1646         }
1647
1648         conn_param.retry_count = SMBD_CM_RETRY;
1649         conn_param.rnr_retry_count = SMBD_CM_RNR_RETRY;
1650         conn_param.flow_control = 0;
1651
1652         log_rdma_event(INFO, "connecting to IP %pI4 port %d\n",
1653                 &addr_in->sin_addr, port);
1654
1655         init_waitqueue_head(&info->conn_wait);
1656         init_waitqueue_head(&info->disconn_wait);
1657         init_waitqueue_head(&info->wait_reassembly_queue);
1658         rc = rdma_connect(info->id, &conn_param);
1659         if (rc) {
1660                 log_rdma_event(ERR, "rdma_connect() failed with %i\n", rc);
1661                 goto rdma_connect_failed;
1662         }
1663
1664         wait_event_interruptible(
1665                 info->conn_wait, info->transport_status != SMBD_CONNECTING);
1666
1667         if (info->transport_status != SMBD_CONNECTED) {
1668                 log_rdma_event(ERR, "rdma_connect failed port=%d\n", port);
1669                 goto rdma_connect_failed;
1670         }
1671
1672         log_rdma_event(INFO, "rdma_connect connected\n");
1673
1674         rc = allocate_caches_and_workqueue(info);
1675         if (rc) {
1676                 log_rdma_event(ERR, "cache allocation failed\n");
1677                 goto allocate_cache_failed;
1678         }
1679
1680         init_waitqueue_head(&info->wait_send_queue);
1681         INIT_DELAYED_WORK(&info->idle_timer_work, idle_connection_timer);
1682         queue_delayed_work(info->workqueue, &info->idle_timer_work,
1683                 info->keep_alive_interval*HZ);
1684
1685         init_waitqueue_head(&info->wait_send_pending);
1686         atomic_set(&info->send_pending, 0);
1687
1688         init_waitqueue_head(&info->wait_post_send);
1689
1690         INIT_WORK(&info->disconnect_work, smbd_disconnect_rdma_work);
1691         INIT_WORK(&info->post_send_credits_work, smbd_post_send_credits);
1692         info->new_credits_offered = 0;
1693         spin_lock_init(&info->lock_new_credits_offered);
1694
1695         rc = smbd_negotiate(info);
1696         if (rc) {
1697                 log_rdma_event(ERR, "smbd_negotiate rc=%d\n", rc);
1698                 goto negotiation_failed;
1699         }
1700
1701         rc = allocate_mr_list(info);
1702         if (rc) {
1703                 log_rdma_mr(ERR, "memory registration allocation failed\n");
1704                 goto allocate_mr_failed;
1705         }
1706
1707         return info;
1708
1709 allocate_mr_failed:
1710         /* At this point, need to a full transport shutdown */
1711         smbd_destroy(server);
1712         return NULL;
1713
1714 negotiation_failed:
1715         cancel_delayed_work_sync(&info->idle_timer_work);
1716         destroy_caches_and_workqueue(info);
1717         info->transport_status = SMBD_NEGOTIATE_FAILED;
1718         init_waitqueue_head(&info->conn_wait);
1719         rdma_disconnect(info->id);
1720         wait_event(info->conn_wait,
1721                 info->transport_status == SMBD_DISCONNECTED);
1722
1723 allocate_cache_failed:
1724 rdma_connect_failed:
1725         rdma_destroy_qp(info->id);
1726
1727 create_qp_failed:
1728 alloc_cq_failed:
1729         if (info->send_cq)
1730                 ib_free_cq(info->send_cq);
1731         if (info->recv_cq)
1732                 ib_free_cq(info->recv_cq);
1733
1734 config_failed:
1735         ib_dealloc_pd(info->pd);
1736         rdma_destroy_id(info->id);
1737
1738 create_id_failed:
1739         kfree(info);
1740         return NULL;
1741 }
1742
1743 struct smbd_connection *smbd_get_connection(
1744         struct TCP_Server_Info *server, struct sockaddr *dstaddr)
1745 {
1746         struct smbd_connection *ret;
1747         int port = SMBD_PORT;
1748
1749 try_again:
1750         ret = _smbd_get_connection(server, dstaddr, port);
1751
1752         /* Try SMB_PORT if SMBD_PORT doesn't work */
1753         if (!ret && port == SMBD_PORT) {
1754                 port = SMB_PORT;
1755                 goto try_again;
1756         }
1757         return ret;
1758 }
1759
1760 /*
1761  * Receive data from receive reassembly queue
1762  * All the incoming data packets are placed in reassembly queue
1763  * buf: the buffer to read data into
1764  * size: the length of data to read
1765  * return value: actual data read
1766  * Note: this implementation copies the data from reassebmly queue to receive
1767  * buffers used by upper layer. This is not the optimal code path. A better way
1768  * to do it is to not have upper layer allocate its receive buffers but rather
1769  * borrow the buffer from reassembly queue, and return it after data is
1770  * consumed. But this will require more changes to upper layer code, and also
1771  * need to consider packet boundaries while they still being reassembled.
1772  */
1773 static int smbd_recv_buf(struct smbd_connection *info, char *buf,
1774                 unsigned int size)
1775 {
1776         struct smbd_response *response;
1777         struct smbd_data_transfer *data_transfer;
1778         int to_copy, to_read, data_read, offset;
1779         u32 data_length, remaining_data_length, data_offset;
1780         int rc;
1781
1782 again:
1783         /*
1784          * No need to hold the reassembly queue lock all the time as we are
1785          * the only one reading from the front of the queue. The transport
1786          * may add more entries to the back of the queue at the same time
1787          */
1788         log_read(INFO, "size=%d info->reassembly_data_length=%d\n", size,
1789                 info->reassembly_data_length);
1790         if (info->reassembly_data_length >= size) {
1791                 int queue_length;
1792                 int queue_removed = 0;
1793
1794                 /*
1795                  * Need to make sure reassembly_data_length is read before
1796                  * reading reassembly_queue_length and calling
1797                  * _get_first_reassembly. This call is lock free
1798                  * as we never read at the end of the queue which are being
1799                  * updated in SOFTIRQ as more data is received
1800                  */
1801                 virt_rmb();
1802                 queue_length = info->reassembly_queue_length;
1803                 data_read = 0;
1804                 to_read = size;
1805                 offset = info->first_entry_offset;
1806                 while (data_read < size) {
1807                         response = _get_first_reassembly(info);
1808                         data_transfer = smbd_response_payload(response);
1809                         data_length = le32_to_cpu(data_transfer->data_length);
1810                         remaining_data_length =
1811                                 le32_to_cpu(
1812                                         data_transfer->remaining_data_length);
1813                         data_offset = le32_to_cpu(data_transfer->data_offset);
1814
1815                         /*
1816                          * The upper layer expects RFC1002 length at the
1817                          * beginning of the payload. Return it to indicate
1818                          * the total length of the packet. This minimize the
1819                          * change to upper layer packet processing logic. This
1820                          * will be eventually remove when an intermediate
1821                          * transport layer is added
1822                          */
1823                         if (response->first_segment && size == 4) {
1824                                 unsigned int rfc1002_len =
1825                                         data_length + remaining_data_length;
1826                                 *((__be32 *)buf) = cpu_to_be32(rfc1002_len);
1827                                 data_read = 4;
1828                                 response->first_segment = false;
1829                                 log_read(INFO, "returning rfc1002 length %d\n",
1830                                         rfc1002_len);
1831                                 goto read_rfc1002_done;
1832                         }
1833
1834                         to_copy = min_t(int, data_length - offset, to_read);
1835                         memcpy(
1836                                 buf + data_read,
1837                                 (char *)data_transfer + data_offset + offset,
1838                                 to_copy);
1839
1840                         /* move on to the next buffer? */
1841                         if (to_copy == data_length - offset) {
1842                                 queue_length--;
1843                                 /*
1844                                  * No need to lock if we are not at the
1845                                  * end of the queue
1846                                  */
1847                                 if (queue_length)
1848                                         list_del(&response->list);
1849                                 else {
1850                                         spin_lock_irq(
1851                                                 &info->reassembly_queue_lock);
1852                                         list_del(&response->list);
1853                                         spin_unlock_irq(
1854                                                 &info->reassembly_queue_lock);
1855                                 }
1856                                 queue_removed++;
1857                                 info->count_reassembly_queue--;
1858                                 info->count_dequeue_reassembly_queue++;
1859                                 put_receive_buffer(info, response);
1860                                 offset = 0;
1861                                 log_read(INFO, "put_receive_buffer offset=0\n");
1862                         } else
1863                                 offset += to_copy;
1864
1865                         to_read -= to_copy;
1866                         data_read += to_copy;
1867
1868                         log_read(INFO, "_get_first_reassembly memcpy %d bytes "
1869                                 "data_transfer_length-offset=%d after that "
1870                                 "to_read=%d data_read=%d offset=%d\n",
1871                                 to_copy, data_length - offset,
1872                                 to_read, data_read, offset);
1873                 }
1874
1875                 spin_lock_irq(&info->reassembly_queue_lock);
1876                 info->reassembly_data_length -= data_read;
1877                 info->reassembly_queue_length -= queue_removed;
1878                 spin_unlock_irq(&info->reassembly_queue_lock);
1879
1880                 info->first_entry_offset = offset;
1881                 log_read(INFO, "returning to thread data_read=%d "
1882                         "reassembly_data_length=%d first_entry_offset=%d\n",
1883                         data_read, info->reassembly_data_length,
1884                         info->first_entry_offset);
1885 read_rfc1002_done:
1886                 return data_read;
1887         }
1888
1889         log_read(INFO, "wait_event on more data\n");
1890         rc = wait_event_interruptible(
1891                 info->wait_reassembly_queue,
1892                 info->reassembly_data_length >= size ||
1893                         info->transport_status != SMBD_CONNECTED);
1894         /* Don't return any data if interrupted */
1895         if (rc)
1896                 return rc;
1897
1898         if (info->transport_status != SMBD_CONNECTED) {
1899                 log_read(ERR, "disconnected\n");
1900                 return -ECONNABORTED;
1901         }
1902
1903         goto again;
1904 }
1905
1906 /*
1907  * Receive a page from receive reassembly queue
1908  * page: the page to read data into
1909  * to_read: the length of data to read
1910  * return value: actual data read
1911  */
1912 static int smbd_recv_page(struct smbd_connection *info,
1913                 struct page *page, unsigned int page_offset,
1914                 unsigned int to_read)
1915 {
1916         int ret;
1917         char *to_address;
1918         void *page_address;
1919
1920         /* make sure we have the page ready for read */
1921         ret = wait_event_interruptible(
1922                 info->wait_reassembly_queue,
1923                 info->reassembly_data_length >= to_read ||
1924                         info->transport_status != SMBD_CONNECTED);
1925         if (ret)
1926                 return ret;
1927
1928         /* now we can read from reassembly queue and not sleep */
1929         page_address = kmap_atomic(page);
1930         to_address = (char *) page_address + page_offset;
1931
1932         log_read(INFO, "reading from page=%p address=%p to_read=%d\n",
1933                 page, to_address, to_read);
1934
1935         ret = smbd_recv_buf(info, to_address, to_read);
1936         kunmap_atomic(page_address);
1937
1938         return ret;
1939 }
1940
1941 /*
1942  * Receive data from transport
1943  * msg: a msghdr point to the buffer, can be ITER_KVEC or ITER_BVEC
1944  * return: total bytes read, or 0. SMB Direct will not do partial read.
1945  */
1946 int smbd_recv(struct smbd_connection *info, struct msghdr *msg)
1947 {
1948         char *buf;
1949         struct page *page;
1950         unsigned int to_read, page_offset;
1951         int rc;
1952
1953         if (iov_iter_rw(&msg->msg_iter) == WRITE) {
1954                 /* It's a bug in upper layer to get there */
1955                 cifs_dbg(VFS, "CIFS: invalid msg iter dir %u\n",
1956                          iov_iter_rw(&msg->msg_iter));
1957                 rc = -EINVAL;
1958                 goto out;
1959         }
1960
1961         switch (iov_iter_type(&msg->msg_iter)) {
1962         case ITER_KVEC:
1963                 buf = msg->msg_iter.kvec->iov_base;
1964                 to_read = msg->msg_iter.kvec->iov_len;
1965                 rc = smbd_recv_buf(info, buf, to_read);
1966                 break;
1967
1968         case ITER_BVEC:
1969                 page = msg->msg_iter.bvec->bv_page;
1970                 page_offset = msg->msg_iter.bvec->bv_offset;
1971                 to_read = msg->msg_iter.bvec->bv_len;
1972                 rc = smbd_recv_page(info, page, page_offset, to_read);
1973                 break;
1974
1975         default:
1976                 /* It's a bug in upper layer to get there */
1977                 cifs_dbg(VFS, "CIFS: invalid msg type %d\n",
1978                          iov_iter_type(&msg->msg_iter));
1979                 rc = -EINVAL;
1980         }
1981
1982 out:
1983         /* SMBDirect will read it all or nothing */
1984         if (rc > 0)
1985                 msg->msg_iter.count = 0;
1986         return rc;
1987 }
1988
1989 /*
1990  * Send data to transport
1991  * Each rqst is transported as a SMBDirect payload
1992  * rqst: the data to write
1993  * return value: 0 if successfully write, otherwise error code
1994  */
1995 int smbd_send(struct TCP_Server_Info *server,
1996         int num_rqst, struct smb_rqst *rqst_array)
1997 {
1998         struct smbd_connection *info = server->smbd_conn;
1999         struct kvec vec;
2000         int nvecs;
2001         int size;
2002         unsigned int buflen, remaining_data_length;
2003         int start, i, j;
2004         int max_iov_size =
2005                 info->max_send_size - sizeof(struct smbd_data_transfer);
2006         struct kvec *iov;
2007         int rc;
2008         struct smb_rqst *rqst;
2009         int rqst_idx;
2010
2011         if (info->transport_status != SMBD_CONNECTED) {
2012                 rc = -EAGAIN;
2013                 goto done;
2014         }
2015
2016         /*
2017          * Add in the page array if there is one. The caller needs to set
2018          * rq_tailsz to PAGE_SIZE when the buffer has multiple pages and
2019          * ends at page boundary
2020          */
2021         remaining_data_length = 0;
2022         for (i = 0; i < num_rqst; i++)
2023                 remaining_data_length += smb_rqst_len(server, &rqst_array[i]);
2024
2025         if (remaining_data_length > info->max_fragmented_send_size) {
2026                 log_write(ERR, "payload size %d > max size %d\n",
2027                         remaining_data_length, info->max_fragmented_send_size);
2028                 rc = -EINVAL;
2029                 goto done;
2030         }
2031
2032         log_write(INFO, "num_rqst=%d total length=%u\n",
2033                         num_rqst, remaining_data_length);
2034
2035         rqst_idx = 0;
2036 next_rqst:
2037         rqst = &rqst_array[rqst_idx];
2038         iov = rqst->rq_iov;
2039
2040         cifs_dbg(FYI, "Sending smb (RDMA): idx=%d smb_len=%lu\n",
2041                 rqst_idx, smb_rqst_len(server, rqst));
2042         for (i = 0; i < rqst->rq_nvec; i++)
2043                 dump_smb(iov[i].iov_base, iov[i].iov_len);
2044
2045
2046         log_write(INFO, "rqst_idx=%d nvec=%d rqst->rq_npages=%d rq_pagesz=%d "
2047                 "rq_tailsz=%d buflen=%lu\n",
2048                 rqst_idx, rqst->rq_nvec, rqst->rq_npages, rqst->rq_pagesz,
2049                 rqst->rq_tailsz, smb_rqst_len(server, rqst));
2050
2051         start = i = 0;
2052         buflen = 0;
2053         while (true) {
2054                 buflen += iov[i].iov_len;
2055                 if (buflen > max_iov_size) {
2056                         if (i > start) {
2057                                 remaining_data_length -=
2058                                         (buflen-iov[i].iov_len);
2059                                 log_write(INFO, "sending iov[] from start=%d "
2060                                         "i=%d nvecs=%d "
2061                                         "remaining_data_length=%d\n",
2062                                         start, i, i-start,
2063                                         remaining_data_length);
2064                                 rc = smbd_post_send_data(
2065                                         info, &iov[start], i-start,
2066                                         remaining_data_length);
2067                                 if (rc)
2068                                         goto done;
2069                         } else {
2070                                 /* iov[start] is too big, break it */
2071                                 nvecs = (buflen+max_iov_size-1)/max_iov_size;
2072                                 log_write(INFO, "iov[%d] iov_base=%p buflen=%d"
2073                                         " break to %d vectors\n",
2074                                         start, iov[start].iov_base,
2075                                         buflen, nvecs);
2076                                 for (j = 0; j < nvecs; j++) {
2077                                         vec.iov_base =
2078                                                 (char *)iov[start].iov_base +
2079                                                 j*max_iov_size;
2080                                         vec.iov_len = max_iov_size;
2081                                         if (j == nvecs-1)
2082                                                 vec.iov_len =
2083                                                         buflen -
2084                                                         max_iov_size*(nvecs-1);
2085                                         remaining_data_length -= vec.iov_len;
2086                                         log_write(INFO,
2087                                                 "sending vec j=%d iov_base=%p"
2088                                                 " iov_len=%zu "
2089                                                 "remaining_data_length=%d\n",
2090                                                 j, vec.iov_base, vec.iov_len,
2091                                                 remaining_data_length);
2092                                         rc = smbd_post_send_data(
2093                                                 info, &vec, 1,
2094                                                 remaining_data_length);
2095                                         if (rc)
2096                                                 goto done;
2097                                 }
2098                                 i++;
2099                                 if (i == rqst->rq_nvec)
2100                                         break;
2101                         }
2102                         start = i;
2103                         buflen = 0;
2104                 } else {
2105                         i++;
2106                         if (i == rqst->rq_nvec) {
2107                                 /* send out all remaining vecs */
2108                                 remaining_data_length -= buflen;
2109                                 log_write(INFO,
2110                                         "sending iov[] from start=%d i=%d "
2111                                         "nvecs=%d remaining_data_length=%d\n",
2112                                         start, i, i-start,
2113                                         remaining_data_length);
2114                                 rc = smbd_post_send_data(info, &iov[start],
2115                                         i-start, remaining_data_length);
2116                                 if (rc)
2117                                         goto done;
2118                                 break;
2119                         }
2120                 }
2121                 log_write(INFO, "looping i=%d buflen=%d\n", i, buflen);
2122         }
2123
2124         /* now sending pages if there are any */
2125         for (i = 0; i < rqst->rq_npages; i++) {
2126                 unsigned int offset;
2127
2128                 rqst_page_get_length(rqst, i, &buflen, &offset);
2129                 nvecs = (buflen + max_iov_size - 1) / max_iov_size;
2130                 log_write(INFO, "sending pages buflen=%d nvecs=%d\n",
2131                         buflen, nvecs);
2132                 for (j = 0; j < nvecs; j++) {
2133                         size = max_iov_size;
2134                         if (j == nvecs-1)
2135                                 size = buflen - j*max_iov_size;
2136                         remaining_data_length -= size;
2137                         log_write(INFO, "sending pages i=%d offset=%d size=%d"
2138                                 " remaining_data_length=%d\n",
2139                                 i, j*max_iov_size+offset, size,
2140                                 remaining_data_length);
2141                         rc = smbd_post_send_page(
2142                                 info, rqst->rq_pages[i],
2143                                 j*max_iov_size + offset,
2144                                 size, remaining_data_length);
2145                         if (rc)
2146                                 goto done;
2147                 }
2148         }
2149
2150         rqst_idx++;
2151         if (rqst_idx < num_rqst)
2152                 goto next_rqst;
2153
2154 done:
2155         /*
2156          * As an optimization, we don't wait for individual I/O to finish
2157          * before sending the next one.
2158          * Send them all and wait for pending send count to get to 0
2159          * that means all the I/Os have been out and we are good to return
2160          */
2161
2162         wait_event(info->wait_send_pending,
2163                 atomic_read(&info->send_pending) == 0);
2164
2165         return rc;
2166 }
2167
2168 static void register_mr_done(struct ib_cq *cq, struct ib_wc *wc)
2169 {
2170         struct smbd_mr *mr;
2171         struct ib_cqe *cqe;
2172
2173         if (wc->status) {
2174                 log_rdma_mr(ERR, "status=%d\n", wc->status);
2175                 cqe = wc->wr_cqe;
2176                 mr = container_of(cqe, struct smbd_mr, cqe);
2177                 smbd_disconnect_rdma_connection(mr->conn);
2178         }
2179 }
2180
2181 /*
2182  * The work queue function that recovers MRs
2183  * We need to call ib_dereg_mr() and ib_alloc_mr() before this MR can be used
2184  * again. Both calls are slow, so finish them in a workqueue. This will not
2185  * block I/O path.
2186  * There is one workqueue that recovers MRs, there is no need to lock as the
2187  * I/O requests calling smbd_register_mr will never update the links in the
2188  * mr_list.
2189  */
2190 static void smbd_mr_recovery_work(struct work_struct *work)
2191 {
2192         struct smbd_connection *info =
2193                 container_of(work, struct smbd_connection, mr_recovery_work);
2194         struct smbd_mr *smbdirect_mr;
2195         int rc;
2196
2197         list_for_each_entry(smbdirect_mr, &info->mr_list, list) {
2198                 if (smbdirect_mr->state == MR_ERROR) {
2199
2200                         /* recover this MR entry */
2201                         rc = ib_dereg_mr(smbdirect_mr->mr);
2202                         if (rc) {
2203                                 log_rdma_mr(ERR,
2204                                         "ib_dereg_mr failed rc=%x\n",
2205                                         rc);
2206                                 smbd_disconnect_rdma_connection(info);
2207                                 continue;
2208                         }
2209
2210                         smbdirect_mr->mr = ib_alloc_mr(
2211                                 info->pd, info->mr_type,
2212                                 info->max_frmr_depth);
2213                         if (IS_ERR(smbdirect_mr->mr)) {
2214                                 log_rdma_mr(ERR,
2215                                         "ib_alloc_mr failed mr_type=%x "
2216                                         "max_frmr_depth=%x\n",
2217                                         info->mr_type,
2218                                         info->max_frmr_depth);
2219                                 smbd_disconnect_rdma_connection(info);
2220                                 continue;
2221                         }
2222                 } else
2223                         /* This MR is being used, don't recover it */
2224                         continue;
2225
2226                 smbdirect_mr->state = MR_READY;
2227
2228                 /* smbdirect_mr->state is updated by this function
2229                  * and is read and updated by I/O issuing CPUs trying
2230                  * to get a MR, the call to atomic_inc_return
2231                  * implicates a memory barrier and guarantees this
2232                  * value is updated before waking up any calls to
2233                  * get_mr() from the I/O issuing CPUs
2234                  */
2235                 if (atomic_inc_return(&info->mr_ready_count) == 1)
2236                         wake_up_interruptible(&info->wait_mr);
2237         }
2238 }
2239
2240 static void destroy_mr_list(struct smbd_connection *info)
2241 {
2242         struct smbd_mr *mr, *tmp;
2243
2244         cancel_work_sync(&info->mr_recovery_work);
2245         list_for_each_entry_safe(mr, tmp, &info->mr_list, list) {
2246                 if (mr->state == MR_INVALIDATED)
2247                         ib_dma_unmap_sg(info->id->device, mr->sgl,
2248                                 mr->sgl_count, mr->dir);
2249                 ib_dereg_mr(mr->mr);
2250                 kfree(mr->sgl);
2251                 kfree(mr);
2252         }
2253 }
2254
2255 /*
2256  * Allocate MRs used for RDMA read/write
2257  * The number of MRs will not exceed hardware capability in responder_resources
2258  * All MRs are kept in mr_list. The MR can be recovered after it's used
2259  * Recovery is done in smbd_mr_recovery_work. The content of list entry changes
2260  * as MRs are used and recovered for I/O, but the list links will not change
2261  */
2262 static int allocate_mr_list(struct smbd_connection *info)
2263 {
2264         int i;
2265         struct smbd_mr *smbdirect_mr, *tmp;
2266
2267         INIT_LIST_HEAD(&info->mr_list);
2268         init_waitqueue_head(&info->wait_mr);
2269         spin_lock_init(&info->mr_list_lock);
2270         atomic_set(&info->mr_ready_count, 0);
2271         atomic_set(&info->mr_used_count, 0);
2272         init_waitqueue_head(&info->wait_for_mr_cleanup);
2273         /* Allocate more MRs (2x) than hardware responder_resources */
2274         for (i = 0; i < info->responder_resources * 2; i++) {
2275                 smbdirect_mr = kzalloc(sizeof(*smbdirect_mr), GFP_KERNEL);
2276                 if (!smbdirect_mr)
2277                         goto out;
2278                 smbdirect_mr->mr = ib_alloc_mr(info->pd, info->mr_type,
2279                                         info->max_frmr_depth);
2280                 if (IS_ERR(smbdirect_mr->mr)) {
2281                         log_rdma_mr(ERR, "ib_alloc_mr failed mr_type=%x "
2282                                 "max_frmr_depth=%x\n",
2283                                 info->mr_type, info->max_frmr_depth);
2284                         goto out;
2285                 }
2286                 smbdirect_mr->sgl = kcalloc(
2287                                         info->max_frmr_depth,
2288                                         sizeof(struct scatterlist),
2289                                         GFP_KERNEL);
2290                 if (!smbdirect_mr->sgl) {
2291                         log_rdma_mr(ERR, "failed to allocate sgl\n");
2292                         ib_dereg_mr(smbdirect_mr->mr);
2293                         goto out;
2294                 }
2295                 smbdirect_mr->state = MR_READY;
2296                 smbdirect_mr->conn = info;
2297
2298                 list_add_tail(&smbdirect_mr->list, &info->mr_list);
2299                 atomic_inc(&info->mr_ready_count);
2300         }
2301         INIT_WORK(&info->mr_recovery_work, smbd_mr_recovery_work);
2302         return 0;
2303
2304 out:
2305         kfree(smbdirect_mr);
2306
2307         list_for_each_entry_safe(smbdirect_mr, tmp, &info->mr_list, list) {
2308                 ib_dereg_mr(smbdirect_mr->mr);
2309                 kfree(smbdirect_mr->sgl);
2310                 kfree(smbdirect_mr);
2311         }
2312         return -ENOMEM;
2313 }
2314
2315 /*
2316  * Get a MR from mr_list. This function waits until there is at least one
2317  * MR available in the list. It may access the list while the
2318  * smbd_mr_recovery_work is recovering the MR list. This doesn't need a lock
2319  * as they never modify the same places. However, there may be several CPUs
2320  * issueing I/O trying to get MR at the same time, mr_list_lock is used to
2321  * protect this situation.
2322  */
2323 static struct smbd_mr *get_mr(struct smbd_connection *info)
2324 {
2325         struct smbd_mr *ret;
2326         int rc;
2327 again:
2328         rc = wait_event_interruptible(info->wait_mr,
2329                 atomic_read(&info->mr_ready_count) ||
2330                 info->transport_status != SMBD_CONNECTED);
2331         if (rc) {
2332                 log_rdma_mr(ERR, "wait_event_interruptible rc=%x\n", rc);
2333                 return NULL;
2334         }
2335
2336         if (info->transport_status != SMBD_CONNECTED) {
2337                 log_rdma_mr(ERR, "info->transport_status=%x\n",
2338                         info->transport_status);
2339                 return NULL;
2340         }
2341
2342         spin_lock(&info->mr_list_lock);
2343         list_for_each_entry(ret, &info->mr_list, list) {
2344                 if (ret->state == MR_READY) {
2345                         ret->state = MR_REGISTERED;
2346                         spin_unlock(&info->mr_list_lock);
2347                         atomic_dec(&info->mr_ready_count);
2348                         atomic_inc(&info->mr_used_count);
2349                         return ret;
2350                 }
2351         }
2352
2353         spin_unlock(&info->mr_list_lock);
2354         /*
2355          * It is possible that we could fail to get MR because other processes may
2356          * try to acquire a MR at the same time. If this is the case, retry it.
2357          */
2358         goto again;
2359 }
2360
2361 /*
2362  * Register memory for RDMA read/write
2363  * pages[]: the list of pages to register memory with
2364  * num_pages: the number of pages to register
2365  * tailsz: if non-zero, the bytes to register in the last page
2366  * writing: true if this is a RDMA write (SMB read), false for RDMA read
2367  * need_invalidate: true if this MR needs to be locally invalidated after I/O
2368  * return value: the MR registered, NULL if failed.
2369  */
2370 struct smbd_mr *smbd_register_mr(
2371         struct smbd_connection *info, struct page *pages[], int num_pages,
2372         int offset, int tailsz, bool writing, bool need_invalidate)
2373 {
2374         struct smbd_mr *smbdirect_mr;
2375         int rc, i;
2376         enum dma_data_direction dir;
2377         struct ib_reg_wr *reg_wr;
2378
2379         if (num_pages > info->max_frmr_depth) {
2380                 log_rdma_mr(ERR, "num_pages=%d max_frmr_depth=%d\n",
2381                         num_pages, info->max_frmr_depth);
2382                 return NULL;
2383         }
2384
2385         smbdirect_mr = get_mr(info);
2386         if (!smbdirect_mr) {
2387                 log_rdma_mr(ERR, "get_mr returning NULL\n");
2388                 return NULL;
2389         }
2390         smbdirect_mr->need_invalidate = need_invalidate;
2391         smbdirect_mr->sgl_count = num_pages;
2392         sg_init_table(smbdirect_mr->sgl, num_pages);
2393
2394         log_rdma_mr(INFO, "num_pages=0x%x offset=0x%x tailsz=0x%x\n",
2395                         num_pages, offset, tailsz);
2396
2397         if (num_pages == 1) {
2398                 sg_set_page(&smbdirect_mr->sgl[0], pages[0], tailsz, offset);
2399                 goto skip_multiple_pages;
2400         }
2401
2402         /* We have at least two pages to register */
2403         sg_set_page(
2404                 &smbdirect_mr->sgl[0], pages[0], PAGE_SIZE - offset, offset);
2405         i = 1;
2406         while (i < num_pages - 1) {
2407                 sg_set_page(&smbdirect_mr->sgl[i], pages[i], PAGE_SIZE, 0);
2408                 i++;
2409         }
2410         sg_set_page(&smbdirect_mr->sgl[i], pages[i],
2411                 tailsz ? tailsz : PAGE_SIZE, 0);
2412
2413 skip_multiple_pages:
2414         dir = writing ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
2415         smbdirect_mr->dir = dir;
2416         rc = ib_dma_map_sg(info->id->device, smbdirect_mr->sgl, num_pages, dir);
2417         if (!rc) {
2418                 log_rdma_mr(ERR, "ib_dma_map_sg num_pages=%x dir=%x rc=%x\n",
2419                         num_pages, dir, rc);
2420                 goto dma_map_error;
2421         }
2422
2423         rc = ib_map_mr_sg(smbdirect_mr->mr, smbdirect_mr->sgl, num_pages,
2424                 NULL, PAGE_SIZE);
2425         if (rc != num_pages) {
2426                 log_rdma_mr(ERR,
2427                         "ib_map_mr_sg failed rc = %d num_pages = %x\n",
2428                         rc, num_pages);
2429                 goto map_mr_error;
2430         }
2431
2432         ib_update_fast_reg_key(smbdirect_mr->mr,
2433                 ib_inc_rkey(smbdirect_mr->mr->rkey));
2434         reg_wr = &smbdirect_mr->wr;
2435         reg_wr->wr.opcode = IB_WR_REG_MR;
2436         smbdirect_mr->cqe.done = register_mr_done;
2437         reg_wr->wr.wr_cqe = &smbdirect_mr->cqe;
2438         reg_wr->wr.num_sge = 0;
2439         reg_wr->wr.send_flags = IB_SEND_SIGNALED;
2440         reg_wr->mr = smbdirect_mr->mr;
2441         reg_wr->key = smbdirect_mr->mr->rkey;
2442         reg_wr->access = writing ?
2443                         IB_ACCESS_REMOTE_WRITE | IB_ACCESS_LOCAL_WRITE :
2444                         IB_ACCESS_REMOTE_READ;
2445
2446         /*
2447          * There is no need for waiting for complemtion on ib_post_send
2448          * on IB_WR_REG_MR. Hardware enforces a barrier and order of execution
2449          * on the next ib_post_send when we actaully send I/O to remote peer
2450          */
2451         rc = ib_post_send(info->id->qp, &reg_wr->wr, NULL);
2452         if (!rc)
2453                 return smbdirect_mr;
2454
2455         log_rdma_mr(ERR, "ib_post_send failed rc=%x reg_wr->key=%x\n",
2456                 rc, reg_wr->key);
2457
2458         /* If all failed, attempt to recover this MR by setting it MR_ERROR*/
2459 map_mr_error:
2460         ib_dma_unmap_sg(info->id->device, smbdirect_mr->sgl,
2461                 smbdirect_mr->sgl_count, smbdirect_mr->dir);
2462
2463 dma_map_error:
2464         smbdirect_mr->state = MR_ERROR;
2465         if (atomic_dec_and_test(&info->mr_used_count))
2466                 wake_up(&info->wait_for_mr_cleanup);
2467
2468         smbd_disconnect_rdma_connection(info);
2469
2470         return NULL;
2471 }
2472
2473 static void local_inv_done(struct ib_cq *cq, struct ib_wc *wc)
2474 {
2475         struct smbd_mr *smbdirect_mr;
2476         struct ib_cqe *cqe;
2477
2478         cqe = wc->wr_cqe;
2479         smbdirect_mr = container_of(cqe, struct smbd_mr, cqe);
2480         smbdirect_mr->state = MR_INVALIDATED;
2481         if (wc->status != IB_WC_SUCCESS) {
2482                 log_rdma_mr(ERR, "invalidate failed status=%x\n", wc->status);
2483                 smbdirect_mr->state = MR_ERROR;
2484         }
2485         complete(&smbdirect_mr->invalidate_done);
2486 }
2487
2488 /*
2489  * Deregister a MR after I/O is done
2490  * This function may wait if remote invalidation is not used
2491  * and we have to locally invalidate the buffer to prevent data is being
2492  * modified by remote peer after upper layer consumes it
2493  */
2494 int smbd_deregister_mr(struct smbd_mr *smbdirect_mr)
2495 {
2496         struct ib_send_wr *wr;
2497         struct smbd_connection *info = smbdirect_mr->conn;
2498         int rc = 0;
2499
2500         if (smbdirect_mr->need_invalidate) {
2501                 /* Need to finish local invalidation before returning */
2502                 wr = &smbdirect_mr->inv_wr;
2503                 wr->opcode = IB_WR_LOCAL_INV;
2504                 smbdirect_mr->cqe.done = local_inv_done;
2505                 wr->wr_cqe = &smbdirect_mr->cqe;
2506                 wr->num_sge = 0;
2507                 wr->ex.invalidate_rkey = smbdirect_mr->mr->rkey;
2508                 wr->send_flags = IB_SEND_SIGNALED;
2509
2510                 init_completion(&smbdirect_mr->invalidate_done);
2511                 rc = ib_post_send(info->id->qp, wr, NULL);
2512                 if (rc) {
2513                         log_rdma_mr(ERR, "ib_post_send failed rc=%x\n", rc);
2514                         smbd_disconnect_rdma_connection(info);
2515                         goto done;
2516                 }
2517                 wait_for_completion(&smbdirect_mr->invalidate_done);
2518                 smbdirect_mr->need_invalidate = false;
2519         } else
2520                 /*
2521                  * For remote invalidation, just set it to MR_INVALIDATED
2522                  * and defer to mr_recovery_work to recover the MR for next use
2523                  */
2524                 smbdirect_mr->state = MR_INVALIDATED;
2525
2526         if (smbdirect_mr->state == MR_INVALIDATED) {
2527                 ib_dma_unmap_sg(
2528                         info->id->device, smbdirect_mr->sgl,
2529                         smbdirect_mr->sgl_count,
2530                         smbdirect_mr->dir);
2531                 smbdirect_mr->state = MR_READY;
2532                 if (atomic_inc_return(&info->mr_ready_count) == 1)
2533                         wake_up_interruptible(&info->wait_mr);
2534         } else
2535                 /*
2536                  * Schedule the work to do MR recovery for future I/Os MR
2537                  * recovery is slow and don't want it to block current I/O
2538                  */
2539                 queue_work(info->workqueue, &info->mr_recovery_work);
2540
2541 done:
2542         if (atomic_dec_and_test(&info->mr_used_count))
2543                 wake_up(&info->wait_for_mr_cleanup);
2544
2545         return rc;
2546 }