drivers/vhost/scsi.c

   1 /*******************************************************************************
   2  * Vhost kernel TCM fabric driver for virtio SCSI initiators
   3  *
   4  * (C) Copyright 2010-2012 RisingTide Systems LLC.
   5  * (C) Copyright 2010-2012 IBM Corp.
   6  *
   7  * Licensed to the Linux Foundation under the General Public License (GPL) version 2.
   8  *
   9  * Authors: Nicholas A. Bellinger <nab@risingtidesystems.com>
  10  *          Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  ****************************************************************************/
  23
  24 #include <linux/module.h>
  25 #include <linux/moduleparam.h>
  26 #include <generated/utsrelease.h>
  27 #include <linux/utsname.h>
  28 #include <linux/init.h>
  29 #include <linux/slab.h>
  30 #include <linux/kthread.h>
  31 #include <linux/types.h>
  32 #include <linux/string.h>
  33 #include <linux/configfs.h>
  34 #include <linux/ctype.h>
  35 #include <linux/compat.h>
  36 #include <linux/eventfd.h>
  37 #include <linux/fs.h>
  38 #include <linux/miscdevice.h>
  39 #include <asm/unaligned.h>
  40 #include <scsi/scsi.h>
  41 #include <scsi/scsi_tcq.h>
  42 #include <target/target_core_base.h>
  43 #include <target/target_core_fabric.h>
  44 #include <target/target_core_fabric_configfs.h>
  45 #include <target/target_core_configfs.h>
  46 #include <target/configfs_macros.h>
  47 #include <linux/vhost.h>
  48 #include <linux/virtio_scsi.h>
  49 #include <linux/llist.h>
  50 #include <linux/bitmap.h>
  51
  52 #include "vhost.h"
  53
  54 #define TCM_VHOST_VERSION  "v0.1"
  55 #define TCM_VHOST_NAMELEN 256
  56 #define TCM_VHOST_MAX_CDB_SIZE 32
  57
  58 struct vhost_scsi_inflight {
  59         /* Wait for the flush operation to finish */
  60         struct completion comp;
  61         /* Refcount for the inflight reqs */
  62         struct kref kref;
  63 };
  64
  65 struct tcm_vhost_cmd {
  66         /* Descriptor from vhost_get_vq_desc() for virt_queue segment */
  67         int tvc_vq_desc;
  68         /* virtio-scsi initiator task attribute */
  69         int tvc_task_attr;
  70         /* virtio-scsi initiator data direction */
  71         enum dma_data_direction tvc_data_direction;
  72         /* Expected data transfer length from virtio-scsi header */
  73         u32 tvc_exp_data_len;
  74         /* The Tag from include/linux/virtio_scsi.h:struct virtio_scsi_cmd_req */
  75         u64 tvc_tag;
  76         /* The number of scatterlists associated with this cmd */
  77         u32 tvc_sgl_count;
  78         /* Saved unpacked SCSI LUN for tcm_vhost_submission_work() */
  79         u32 tvc_lun;
  80         /* Pointer to the SGL formatted memory from virtio-scsi */
  81         struct scatterlist *tvc_sgl;
  82         /* Pointer to response */
  83         struct virtio_scsi_cmd_resp __user *tvc_resp;
  84         /* Pointer to vhost_scsi for our device */
  85         struct vhost_scsi *tvc_vhost;
  86         /* Pointer to vhost_virtqueue for the cmd */
  87         struct vhost_virtqueue *tvc_vq;
  88         /* Pointer to vhost nexus memory */
  89         struct tcm_vhost_nexus *tvc_nexus;
  90         /* The TCM I/O descriptor that is accessed via container_of() */
  91         struct se_cmd tvc_se_cmd;
  92         /* work item used for cmwq dispatch to tcm_vhost_submission_work() */
  93         struct work_struct work;
  94         /* Copy of the incoming SCSI command descriptor block (CDB) */
  95         unsigned char tvc_cdb[TCM_VHOST_MAX_CDB_SIZE];
  96         /* Sense buffer that will be mapped into outgoing status */
  97         unsigned char tvc_sense_buf[TRANSPORT_SENSE_BUFFER];
  98         /* Completed commands list, serviced from vhost worker thread */
  99         struct llist_node tvc_completion_list;
 100         /* Used to track inflight cmd */
 101         struct vhost_scsi_inflight *inflight;
 102 };
 103
 104 struct tcm_vhost_nexus {
 105         /* Pointer to TCM session for I_T Nexus */
 106         struct se_session *tvn_se_sess;
 107 };
 108
 109 struct tcm_vhost_nacl {
 110         /* Binary World Wide unique Port Name for Vhost Initiator port */
 111         u64 iport_wwpn;
 112         /* ASCII formatted WWPN for Sas Initiator port */
 113         char iport_name[TCM_VHOST_NAMELEN];
 114         /* Returned by tcm_vhost_make_nodeacl() */
 115         struct se_node_acl se_node_acl;
 116 };
 117
 118 struct tcm_vhost_tpg {
 119         /* Vhost port target portal group tag for TCM */
 120         u16 tport_tpgt;
 121         /* Used to track number of TPG Port/Lun Links wrt to explict I_T Nexus shutdown */
 122         int tv_tpg_port_count;
 123         /* Used for vhost_scsi device reference to tpg_nexus, protected by tv_tpg_mutex */
 124         int tv_tpg_vhost_count;
 125         /* list for tcm_vhost_list */
 126         struct list_head tv_tpg_list;
 127         /* Used to protect access for tpg_nexus */
 128         struct mutex tv_tpg_mutex;
 129         /* Pointer to the TCM VHost I_T Nexus for this TPG endpoint */
 130         struct tcm_vhost_nexus *tpg_nexus;
 131         /* Pointer back to tcm_vhost_tport */
 132         struct tcm_vhost_tport *tport;
 133         /* Returned by tcm_vhost_make_tpg() */
 134         struct se_portal_group se_tpg;
 135         /* Pointer back to vhost_scsi, protected by tv_tpg_mutex */
 136         struct vhost_scsi *vhost_scsi;
 137 };
 138
 139 struct tcm_vhost_tport {
 140         /* SCSI protocol the tport is providing */
 141         u8 tport_proto_id;
 142         /* Binary World Wide unique Port Name for Vhost Target port */
 143         u64 tport_wwpn;
 144         /* ASCII formatted WWPN for Vhost Target port */
 145         char tport_name[TCM_VHOST_NAMELEN];
 146         /* Returned by tcm_vhost_make_tport() */
 147         struct se_wwn tport_wwn;
 148 };
 149
 150 struct tcm_vhost_evt {
 151         /* event to be sent to guest */
 152         struct virtio_scsi_event event;
 153         /* event list, serviced from vhost worker thread */
 154         struct llist_node list;
 155 };
 156
 157 enum {
 158         VHOST_SCSI_VQ_CTL = 0,
 159         VHOST_SCSI_VQ_EVT = 1,
 160         VHOST_SCSI_VQ_IO = 2,
 161 };
 162
 163 enum {
 164         VHOST_SCSI_FEATURES = VHOST_FEATURES | (1ULL << VIRTIO_SCSI_F_HOTPLUG)
 165 };
 166
 167 #define VHOST_SCSI_MAX_TARGET   256
 168 #define VHOST_SCSI_MAX_VQ       128
 169 #define VHOST_SCSI_MAX_EVENT    128
 170
 171 struct vhost_scsi_virtqueue {
 172         struct vhost_virtqueue vq;
 173         /*
 174          * Reference counting for inflight reqs, used for flush operation. At
 175          * each time, one reference tracks new commands submitted, while we
 176          * wait for another one to reach 0.
 177          */
 178         struct vhost_scsi_inflight inflights[2];
 179         /*
 180          * Indicate current inflight in use, protected by vq->mutex.
 181          * Writers must also take dev mutex and flush under it.
 182          */
 183         int inflight_idx;
 184 };
 185
 186 struct vhost_scsi {
 187         /* Protected by vhost_scsi->dev.mutex */
 188         struct tcm_vhost_tpg **vs_tpg;
 189         char vs_vhost_wwpn[TRANSPORT_IQN_LEN];
 190
 191         struct vhost_dev dev;
 192         struct vhost_scsi_virtqueue vqs[VHOST_SCSI_MAX_VQ];
 193
 194         struct vhost_work vs_completion_work; /* cmd completion work item */
 195         struct llist_head vs_completion_list; /* cmd completion queue */
 196
 197         struct vhost_work vs_event_work; /* evt injection work item */
 198         struct llist_head vs_event_list; /* evt injection queue */
 199
 200         bool vs_events_missed; /* any missed events, protected by vq->mutex */
 201         int vs_events_nr; /* num of pending events, protected by vq->mutex */
 202 };
 203
 204 /* Local pointer to allocated TCM configfs fabric module */
 205 static struct target_fabric_configfs *tcm_vhost_fabric_configfs;
 206
 207 static struct workqueue_struct *tcm_vhost_workqueue;
 208
 209 /* Global spinlock to protect tcm_vhost TPG list for vhost IOCTL access */
 210 static DEFINE_MUTEX(tcm_vhost_mutex);
 211 static LIST_HEAD(tcm_vhost_list);
 212
 213 static int iov_num_pages(struct iovec *iov)
 214 {
 215         return (PAGE_ALIGN((unsigned long)iov->iov_base + iov->iov_len) -
 216                ((unsigned long)iov->iov_base & PAGE_MASK)) >> PAGE_SHIFT;
 217 }
 218
 219 static void tcm_vhost_done_inflight(struct kref *kref)
 220 {
 221         struct vhost_scsi_inflight *inflight;
 222
 223         inflight = container_of(kref, struct vhost_scsi_inflight, kref);
 224         complete(&inflight->comp);
 225 }
 226
 227 static void tcm_vhost_init_inflight(struct vhost_scsi *vs,
 228                                     struct vhost_scsi_inflight *old_inflight[])
 229 {
 230         struct vhost_scsi_inflight *new_inflight;
 231         struct vhost_virtqueue *vq;
 232         int idx, i;
 233
 234         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
 235                 vq = &vs->vqs[i].vq;
 236
 237                 mutex_lock(&vq->mutex);
 238
 239                 /* store old infight */
 240                 idx = vs->vqs[i].inflight_idx;
 241                 if (old_inflight)
 242                         old_inflight[i] = &vs->vqs[i].inflights[idx];
 243
 244                 /* setup new infight */
 245                 vs->vqs[i].inflight_idx = idx ^ 1;
 246                 new_inflight = &vs->vqs[i].inflights[idx ^ 1];
 247                 kref_init(&new_inflight->kref);
 248                 init_completion(&new_inflight->comp);
 249
 250                 mutex_unlock(&vq->mutex);
 251         }
 252 }
 253
 254 static struct vhost_scsi_inflight *
 255 tcm_vhost_get_inflight(struct vhost_virtqueue *vq)
 256 {
 257         struct vhost_scsi_inflight *inflight;
 258         struct vhost_scsi_virtqueue *svq;
 259
 260         svq = container_of(vq, struct vhost_scsi_virtqueue, vq);
 261         inflight = &svq->inflights[svq->inflight_idx];
 262         kref_get(&inflight->kref);
 263
 264         return inflight;
 265 }
 266
 267 static void tcm_vhost_put_inflight(struct vhost_scsi_inflight *inflight)
 268 {
 269         kref_put(&inflight->kref, tcm_vhost_done_inflight);
 270 }
 271
 272 static int tcm_vhost_check_true(struct se_portal_group *se_tpg)
 273 {
 274         return 1;
 275 }
 276
 277 static int tcm_vhost_check_false(struct se_portal_group *se_tpg)
 278 {
 279         return 0;
 280 }
 281
 282 static char *tcm_vhost_get_fabric_name(void)
 283 {
 284         return "vhost";
 285 }
 286
 287 static u8 tcm_vhost_get_fabric_proto_ident(struct se_portal_group *se_tpg)
 288 {
 289         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 290                                 struct tcm_vhost_tpg, se_tpg);
 291         struct tcm_vhost_tport *tport = tpg->tport;
 292
 293         switch (tport->tport_proto_id) {
 294         case SCSI_PROTOCOL_SAS:
 295                 return sas_get_fabric_proto_ident(se_tpg);
 296         case SCSI_PROTOCOL_FCP:
 297                 return fc_get_fabric_proto_ident(se_tpg);
 298         case SCSI_PROTOCOL_ISCSI:
 299                 return iscsi_get_fabric_proto_ident(se_tpg);
 300         default:
 301                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 302                         " SAS emulation\n", tport->tport_proto_id);
 303                 break;
 304         }
 305
 306         return sas_get_fabric_proto_ident(se_tpg);
 307 }
 308
 309 static char *tcm_vhost_get_fabric_wwn(struct se_portal_group *se_tpg)
 310 {
 311         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 312                                 struct tcm_vhost_tpg, se_tpg);
 313         struct tcm_vhost_tport *tport = tpg->tport;
 314
 315         return &tport->tport_name[0];
 316 }
 317
 318 static u16 tcm_vhost_get_tag(struct se_portal_group *se_tpg)
 319 {
 320         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 321                                 struct tcm_vhost_tpg, se_tpg);
 322         return tpg->tport_tpgt;
 323 }
 324
 325 static u32 tcm_vhost_get_default_depth(struct se_portal_group *se_tpg)
 326 {
 327         return 1;
 328 }
 329
 330 static u32
 331 tcm_vhost_get_pr_transport_id(struct se_portal_group *se_tpg,
 332                               struct se_node_acl *se_nacl,
 333                               struct t10_pr_registration *pr_reg,
 334                               int *format_code,
 335                               unsigned char *buf)
 336 {
 337         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 338                                 struct tcm_vhost_tpg, se_tpg);
 339         struct tcm_vhost_tport *tport = tpg->tport;
 340
 341         switch (tport->tport_proto_id) {
 342         case SCSI_PROTOCOL_SAS:
 343                 return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 344                                         format_code, buf);
 345         case SCSI_PROTOCOL_FCP:
 346                 return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 347                                         format_code, buf);
 348         case SCSI_PROTOCOL_ISCSI:
 349                 return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 350                                         format_code, buf);
 351         default:
 352                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 353                         " SAS emulation\n", tport->tport_proto_id);
 354                 break;
 355         }
 356
 357         return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 358                         format_code, buf);
 359 }
 360
 361 static u32
 362 tcm_vhost_get_pr_transport_id_len(struct se_portal_group *se_tpg,
 363                                   struct se_node_acl *se_nacl,
 364                                   struct t10_pr_registration *pr_reg,
 365                                   int *format_code)
 366 {
 367         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 368                                 struct tcm_vhost_tpg, se_tpg);
 369         struct tcm_vhost_tport *tport = tpg->tport;
 370
 371         switch (tport->tport_proto_id) {
 372         case SCSI_PROTOCOL_SAS:
 373                 return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 374                                         format_code);
 375         case SCSI_PROTOCOL_FCP:
 376                 return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 377                                         format_code);
 378         case SCSI_PROTOCOL_ISCSI:
 379                 return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 380                                         format_code);
 381         default:
 382                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 383                         " SAS emulation\n", tport->tport_proto_id);
 384                 break;
 385         }
 386
 387         return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 388                         format_code);
 389 }
 390
 391 static char *
 392 tcm_vhost_parse_pr_out_transport_id(struct se_portal_group *se_tpg,
 393                                     const char *buf,
 394                                     u32 *out_tid_len,
 395                                     char **port_nexus_ptr)
 396 {
 397         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 398                                 struct tcm_vhost_tpg, se_tpg);
 399         struct tcm_vhost_tport *tport = tpg->tport;
 400
 401         switch (tport->tport_proto_id) {
 402         case SCSI_PROTOCOL_SAS:
 403                 return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 404                                         port_nexus_ptr);
 405         case SCSI_PROTOCOL_FCP:
 406                 return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 407                                         port_nexus_ptr);
 408         case SCSI_PROTOCOL_ISCSI:
 409                 return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 410                                         port_nexus_ptr);
 411         default:
 412                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 413                         " SAS emulation\n", tport->tport_proto_id);
 414                 break;
 415         }
 416
 417         return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 418                         port_nexus_ptr);
 419 }
 420
 421 static struct se_node_acl *
 422 tcm_vhost_alloc_fabric_acl(struct se_portal_group *se_tpg)
 423 {
 424         struct tcm_vhost_nacl *nacl;
 425
 426         nacl = kzalloc(sizeof(struct tcm_vhost_nacl), GFP_KERNEL);
 427         if (!nacl) {
 428                 pr_err("Unable to allocate struct tcm_vhost_nacl\n");
 429                 return NULL;
 430         }
 431
 432         return &nacl->se_node_acl;
 433 }
 434
 435 static void
 436 tcm_vhost_release_fabric_acl(struct se_portal_group *se_tpg,
 437                              struct se_node_acl *se_nacl)
 438 {
 439         struct tcm_vhost_nacl *nacl = container_of(se_nacl,
 440                         struct tcm_vhost_nacl, se_node_acl);
 441         kfree(nacl);
 442 }
 443
 444 static u32 tcm_vhost_tpg_get_inst_index(struct se_portal_group *se_tpg)
 445 {
 446         return 1;
 447 }
 448
 449 static void tcm_vhost_release_cmd(struct se_cmd *se_cmd)
 450 {
 451         return;
 452 }
 453
 454 static int tcm_vhost_shutdown_session(struct se_session *se_sess)
 455 {
 456         return 0;
 457 }
 458
 459 static void tcm_vhost_close_session(struct se_session *se_sess)
 460 {
 461         return;
 462 }
 463
 464 static u32 tcm_vhost_sess_get_index(struct se_session *se_sess)
 465 {
 466         return 0;
 467 }
 468
 469 static int tcm_vhost_write_pending(struct se_cmd *se_cmd)
 470 {
 471         /* Go ahead and process the write immediately */
 472         target_execute_cmd(se_cmd);
 473         return 0;
 474 }
 475
 476 static int tcm_vhost_write_pending_status(struct se_cmd *se_cmd)
 477 {
 478         return 0;
 479 }
 480
 481 static void tcm_vhost_set_default_node_attrs(struct se_node_acl *nacl)
 482 {
 483         return;
 484 }
 485
 486 static u32 tcm_vhost_get_task_tag(struct se_cmd *se_cmd)
 487 {
 488         return 0;
 489 }
 490
 491 static int tcm_vhost_get_cmd_state(struct se_cmd *se_cmd)
 492 {
 493         return 0;
 494 }
 495
 496 static void vhost_scsi_complete_cmd(struct tcm_vhost_cmd *cmd)
 497 {
 498         struct vhost_scsi *vs = cmd->tvc_vhost;
 499
 500         llist_add(&cmd->tvc_completion_list, &vs->vs_completion_list);
 501
 502         vhost_work_queue(&vs->dev, &vs->vs_completion_work);
 503 }
 504
 505 static int tcm_vhost_queue_data_in(struct se_cmd *se_cmd)
 506 {
 507         struct tcm_vhost_cmd *cmd = container_of(se_cmd,
 508                                 struct tcm_vhost_cmd, tvc_se_cmd);
 509         vhost_scsi_complete_cmd(cmd);
 510         return 0;
 511 }
 512
 513 static int tcm_vhost_queue_status(struct se_cmd *se_cmd)
 514 {
 515         struct tcm_vhost_cmd *cmd = container_of(se_cmd,
 516                                 struct tcm_vhost_cmd, tvc_se_cmd);
 517         vhost_scsi_complete_cmd(cmd);
 518         return 0;
 519 }
 520
 521 static int tcm_vhost_queue_tm_rsp(struct se_cmd *se_cmd)
 522 {
 523         return 0;
 524 }
 525
 526 static void tcm_vhost_free_evt(struct vhost_scsi *vs, struct tcm_vhost_evt *evt)
 527 {
 528         vs->vs_events_nr--;
 529         kfree(evt);
 530 }
 531
 532 static struct tcm_vhost_evt *
 533 tcm_vhost_allocate_evt(struct vhost_scsi *vs,
 534                        u32 event, u32 reason)
 535 {
 536         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 537         struct tcm_vhost_evt *evt;
 538
 539         if (vs->vs_events_nr > VHOST_SCSI_MAX_EVENT) {
 540                 vs->vs_events_missed = true;
 541                 return NULL;
 542         }
 543
 544         evt = kzalloc(sizeof(*evt), GFP_KERNEL);
 545         if (!evt) {
 546                 vq_err(vq, "Failed to allocate tcm_vhost_evt\n");
 547                 vs->vs_events_missed = true;
 548                 return NULL;
 549         }
 550
 551         evt->event.event = event;
 552         evt->event.reason = reason;
 553         vs->vs_events_nr++;
 554
 555         return evt;
 556 }
 557
 558 static void vhost_scsi_free_cmd(struct tcm_vhost_cmd *cmd)
 559 {
 560         struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
 561
 562         /* TODO locking against target/backend threads? */
 563         transport_generic_free_cmd(se_cmd, 1);
 564
 565         if (cmd->tvc_sgl_count) {
 566                 u32 i;
 567                 for (i = 0; i < cmd->tvc_sgl_count; i++)
 568                         put_page(sg_page(&cmd->tvc_sgl[i]));
 569
 570                 kfree(cmd->tvc_sgl);
 571         }
 572
 573         tcm_vhost_put_inflight(cmd->inflight);
 574
 575         kfree(cmd);
 576 }
 577
 578 static void
 579 tcm_vhost_do_evt_work(struct vhost_scsi *vs, struct tcm_vhost_evt *evt)
 580 {
 581         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 582         struct virtio_scsi_event *event = &evt->event;
 583         struct virtio_scsi_event __user *eventp;
 584         unsigned out, in;
 585         int head, ret;
 586
 587         if (!vq->private_data) {
 588                 vs->vs_events_missed = true;
 589                 return;
 590         }
 591
 592 again:
 593         vhost_disable_notify(&vs->dev, vq);
 594         head = vhost_get_vq_desc(&vs->dev, vq, vq->iov,
 595                         ARRAY_SIZE(vq->iov), &out, &in,
 596                         NULL, NULL);
 597         if (head < 0) {
 598                 vs->vs_events_missed = true;
 599                 return;
 600         }
 601         if (head == vq->num) {
 602                 if (vhost_enable_notify(&vs->dev, vq))
 603                         goto again;
 604                 vs->vs_events_missed = true;
 605                 return;
 606         }
 607
 608         if ((vq->iov[out].iov_len != sizeof(struct virtio_scsi_event))) {
 609                 vq_err(vq, "Expecting virtio_scsi_event, got %zu bytes\n",
 610                                 vq->iov[out].iov_len);
 611                 vs->vs_events_missed = true;
 612                 return;
 613         }
 614
 615         if (vs->vs_events_missed) {
 616                 event->event |= VIRTIO_SCSI_T_EVENTS_MISSED;
 617                 vs->vs_events_missed = false;
 618         }
 619
 620         eventp = vq->iov[out].iov_base;
 621         ret = __copy_to_user(eventp, event, sizeof(*event));
 622         if (!ret)
 623                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 624         else
 625                 vq_err(vq, "Faulted on tcm_vhost_send_event\n");
 626 }
 627
 628 static void tcm_vhost_evt_work(struct vhost_work *work)
 629 {
 630         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 631                                         vs_event_work);
 632         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 633         struct tcm_vhost_evt *evt;
 634         struct llist_node *llnode;
 635
 636         mutex_lock(&vq->mutex);
 637         llnode = llist_del_all(&vs->vs_event_list);
 638         while (llnode) {
 639                 evt = llist_entry(llnode, struct tcm_vhost_evt, list);
 640                 llnode = llist_next(llnode);
 641                 tcm_vhost_do_evt_work(vs, evt);
 642                 tcm_vhost_free_evt(vs, evt);
 643         }
 644         mutex_unlock(&vq->mutex);
 645 }
 646
 647 /* Fill in status and signal that we are done processing this command
 648  *
 649  * This is scheduled in the vhost work queue so we are called with the owner
 650  * process mm and can access the vring.
 651  */
 652 static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
 653 {
 654         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 655                                         vs_completion_work);
 656         DECLARE_BITMAP(signal, VHOST_SCSI_MAX_VQ);
 657         struct virtio_scsi_cmd_resp v_rsp;
 658         struct tcm_vhost_cmd *cmd;
 659         struct llist_node *llnode;
 660         struct se_cmd *se_cmd;
 661         int ret, vq;
 662
 663         bitmap_zero(signal, VHOST_SCSI_MAX_VQ);
 664         llnode = llist_del_all(&vs->vs_completion_list);
 665         while (llnode) {
 666                 cmd = llist_entry(llnode, struct tcm_vhost_cmd,
 667                                      tvc_completion_list);
 668                 llnode = llist_next(llnode);
 669                 se_cmd = &cmd->tvc_se_cmd;
 670
 671                 pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__,
 672                         cmd, se_cmd->residual_count, se_cmd->scsi_status);
 673
 674                 memset(&v_rsp, 0, sizeof(v_rsp));
 675                 v_rsp.resid = se_cmd->residual_count;
 676                 /* TODO is status_qualifier field needed? */
 677                 v_rsp.status = se_cmd->scsi_status;
 678                 v_rsp.sense_len = se_cmd->scsi_sense_length;
 679                 memcpy(v_rsp.sense, cmd->tvc_sense_buf,
 680                        v_rsp.sense_len);
 681                 ret = copy_to_user(cmd->tvc_resp, &v_rsp, sizeof(v_rsp));
 682                 if (likely(ret == 0)) {
 683                         struct vhost_scsi_virtqueue *q;
 684                         vhost_add_used(cmd->tvc_vq, cmd->tvc_vq_desc, 0);
 685                         q = container_of(cmd->tvc_vq, struct vhost_scsi_virtqueue, vq);
 686                         vq = q - vs->vqs;
 687                         __set_bit(vq, signal);
 688                 } else
 689                         pr_err("Faulted on virtio_scsi_cmd_resp\n");
 690
 691                 vhost_scsi_free_cmd(cmd);
 692         }
 693
 694         vq = -1;
 695         while ((vq = find_next_bit(signal, VHOST_SCSI_MAX_VQ, vq + 1))
 696                 < VHOST_SCSI_MAX_VQ)
 697                 vhost_signal(&vs->dev, &vs->vqs[vq].vq);
 698 }
 699
 700 static struct tcm_vhost_cmd *
 701 vhost_scsi_allocate_cmd(struct vhost_virtqueue *vq,
 702                         struct tcm_vhost_tpg *tpg,
 703                         struct virtio_scsi_cmd_req *v_req,
 704                         u32 exp_data_len,
 705                         int data_direction)
 706 {
 707         struct tcm_vhost_cmd *cmd;
 708         struct tcm_vhost_nexus *tv_nexus;
 709
 710         tv_nexus = tpg->tpg_nexus;
 711         if (!tv_nexus) {
 712                 pr_err("Unable to locate active struct tcm_vhost_nexus\n");
 713                 return ERR_PTR(-EIO);
 714         }
 715
 716         cmd = kzalloc(sizeof(struct tcm_vhost_cmd), GFP_ATOMIC);
 717         if (!cmd) {
 718                 pr_err("Unable to allocate struct tcm_vhost_cmd\n");
 719                 return ERR_PTR(-ENOMEM);
 720         }
 721         cmd->tvc_tag = v_req->tag;
 722         cmd->tvc_task_attr = v_req->task_attr;
 723         cmd->tvc_exp_data_len = exp_data_len;
 724         cmd->tvc_data_direction = data_direction;
 725         cmd->tvc_nexus = tv_nexus;
 726         cmd->inflight = tcm_vhost_get_inflight(vq);
 727
 728         return cmd;
 729 }
 730
 731 /*
 732  * Map a user memory range into a scatterlist
 733  *
 734  * Returns the number of scatterlist entries used or -errno on error.
 735  */
 736 static int
 737 vhost_scsi_map_to_sgl(struct scatterlist *sgl,
 738                       unsigned int sgl_count,
 739                       struct iovec *iov,
 740                       int write)
 741 {
 742         unsigned int npages = 0, pages_nr, offset, nbytes;
 743         struct scatterlist *sg = sgl;
 744         void __user *ptr = iov->iov_base;
 745         size_t len = iov->iov_len;
 746         struct page **pages;
 747         int ret, i;
 748
 749         pages_nr = iov_num_pages(iov);
 750         if (pages_nr > sgl_count)
 751                 return -ENOBUFS;
 752
 753         pages = kmalloc(pages_nr * sizeof(struct page *), GFP_KERNEL);
 754         if (!pages)
 755                 return -ENOMEM;
 756
 757         ret = get_user_pages_fast((unsigned long)ptr, pages_nr, write, pages);
 758         /* No pages were pinned */
 759         if (ret < 0)
 760                 goto out;
 761         /* Less pages pinned than wanted */
 762         if (ret != pages_nr) {
 763                 for (i = 0; i < ret; i++)
 764                         put_page(pages[i]);
 765                 ret = -EFAULT;
 766                 goto out;
 767         }
 768
 769         while (len > 0) {
 770                 offset = (uintptr_t)ptr & ~PAGE_MASK;
 771                 nbytes = min_t(unsigned int, PAGE_SIZE - offset, len);
 772                 sg_set_page(sg, pages[npages], nbytes, offset);
 773                 ptr += nbytes;
 774                 len -= nbytes;
 775                 sg++;
 776                 npages++;
 777         }
 778
 779 out:
 780         kfree(pages);
 781         return ret;
 782 }
 783
 784 static int
 785 vhost_scsi_map_iov_to_sgl(struct tcm_vhost_cmd *cmd,
 786                           struct iovec *iov,
 787                           unsigned int niov,
 788                           int write)
 789 {
 790         int ret;
 791         unsigned int i;
 792         u32 sgl_count;
 793         struct scatterlist *sg;
 794
 795         /*
 796          * Find out how long sglist needs to be
 797          */
 798         sgl_count = 0;
 799         for (i = 0; i < niov; i++)
 800                 sgl_count += iov_num_pages(&iov[i]);
 801
 802         /* TODO overflow checking */
 803
 804         sg = kmalloc(sizeof(cmd->tvc_sgl[0]) * sgl_count, GFP_ATOMIC);
 805         if (!sg)
 806                 return -ENOMEM;
 807         pr_debug("%s sg %p sgl_count %u is_err %d\n", __func__,
 808                sg, sgl_count, !sg);
 809         sg_init_table(sg, sgl_count);
 810
 811         cmd->tvc_sgl = sg;
 812         cmd->tvc_sgl_count = sgl_count;
 813
 814         pr_debug("Mapping %u iovecs for %u pages\n", niov, sgl_count);
 815         for (i = 0; i < niov; i++) {
 816                 ret = vhost_scsi_map_to_sgl(sg, sgl_count, &iov[i], write);
 817                 if (ret < 0) {
 818                         for (i = 0; i < cmd->tvc_sgl_count; i++)
 819                                 put_page(sg_page(&cmd->tvc_sgl[i]));
 820                         kfree(cmd->tvc_sgl);
 821                         cmd->tvc_sgl = NULL;
 822                         cmd->tvc_sgl_count = 0;
 823                         return ret;
 824                 }
 825
 826                 sg += ret;
 827                 sgl_count -= ret;
 828         }
 829         return 0;
 830 }
 831
 832 static void tcm_vhost_submission_work(struct work_struct *work)
 833 {
 834         struct tcm_vhost_cmd *cmd =
 835                 container_of(work, struct tcm_vhost_cmd, work);
 836         struct tcm_vhost_nexus *tv_nexus;
 837         struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
 838         struct scatterlist *sg_ptr, *sg_bidi_ptr = NULL;
 839         int rc, sg_no_bidi = 0;
 840
 841         if (cmd->tvc_sgl_count) {
 842                 sg_ptr = cmd->tvc_sgl;
 843 /* FIXME: Fix BIDI operation in tcm_vhost_submission_work() */
 844 #if 0
 845                 if (se_cmd->se_cmd_flags & SCF_BIDI) {
 846                         sg_bidi_ptr = NULL;
 847                         sg_no_bidi = 0;
 848                 }
 849 #endif
 850         } else {
 851                 sg_ptr = NULL;
 852         }
 853         tv_nexus = cmd->tvc_nexus;
 854
 855         rc = target_submit_cmd_map_sgls(se_cmd, tv_nexus->tvn_se_sess,
 856                         cmd->tvc_cdb, &cmd->tvc_sense_buf[0],
 857                         cmd->tvc_lun, cmd->tvc_exp_data_len,
 858                         cmd->tvc_task_attr, cmd->tvc_data_direction,
 859                         0, sg_ptr, cmd->tvc_sgl_count,
 860                         sg_bidi_ptr, sg_no_bidi);
 861         if (rc < 0) {
 862                 transport_send_check_condition_and_sense(se_cmd,
 863                                 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
 864                 transport_generic_free_cmd(se_cmd, 0);
 865         }
 866 }
 867
 868 static void
 869 vhost_scsi_send_bad_target(struct vhost_scsi *vs,
 870                            struct vhost_virtqueue *vq,
 871                            int head, unsigned out)
 872 {
 873         struct virtio_scsi_cmd_resp __user *resp;
 874         struct virtio_scsi_cmd_resp rsp;
 875         int ret;
 876
 877         memset(&rsp, 0, sizeof(rsp));
 878         rsp.response = VIRTIO_SCSI_S_BAD_TARGET;
 879         resp = vq->iov[out].iov_base;
 880         ret = __copy_to_user(resp, &rsp, sizeof(rsp));
 881         if (!ret)
 882                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 883         else
 884                 pr_err("Faulted on virtio_scsi_cmd_resp\n");
 885 }
 886
 887 static void
 888 vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
 889 {
 890         struct tcm_vhost_tpg **vs_tpg;
 891         struct virtio_scsi_cmd_req v_req;
 892         struct tcm_vhost_tpg *tpg;
 893         struct tcm_vhost_cmd *cmd;
 894         u32 exp_data_len, data_first, data_num, data_direction;
 895         unsigned out, in, i;
 896         int head, ret;
 897         u8 target;
 898
 899         mutex_lock(&vq->mutex);
 900         /*
 901          * We can handle the vq only after the endpoint is setup by calling the
 902          * VHOST_SCSI_SET_ENDPOINT ioctl.
 903          */
 904         vs_tpg = vq->private_data;
 905         if (!vs_tpg)
 906                 goto out;
 907
 908         vhost_disable_notify(&vs->dev, vq);
 909
 910         for (;;) {
 911                 head = vhost_get_vq_desc(&vs->dev, vq, vq->iov,
 912                                         ARRAY_SIZE(vq->iov), &out, &in,
 913                                         NULL, NULL);
 914                 pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n",
 915                                         head, out, in);
 916                 /* On error, stop handling until the next kick. */
 917                 if (unlikely(head < 0))
 918                         break;
 919                 /* Nothing new?  Wait for eventfd to tell us they refilled. */
 920                 if (head == vq->num) {
 921                         if (unlikely(vhost_enable_notify(&vs->dev, vq))) {
 922                                 vhost_disable_notify(&vs->dev, vq);
 923                                 continue;
 924                         }
 925                         break;
 926                 }
 927
 928 /* FIXME: BIDI operation */
 929                 if (out == 1 && in == 1) {
 930                         data_direction = DMA_NONE;
 931                         data_first = 0;
 932                         data_num = 0;
 933                 } else if (out == 1 && in > 1) {
 934                         data_direction = DMA_FROM_DEVICE;
 935                         data_first = out + 1;
 936                         data_num = in - 1;
 937                 } else if (out > 1 && in == 1) {
 938                         data_direction = DMA_TO_DEVICE;
 939                         data_first = 1;
 940                         data_num = out - 1;
 941                 } else {
 942                         vq_err(vq, "Invalid buffer layout out: %u in: %u\n",
 943                                         out, in);
 944                         break;
 945                 }
 946
 947                 /*
 948                  * Check for a sane resp buffer so we can report errors to
 949                  * the guest.
 950                  */
 951                 if (unlikely(vq->iov[out].iov_len !=
 952                                         sizeof(struct virtio_scsi_cmd_resp))) {
 953                         vq_err(vq, "Expecting virtio_scsi_cmd_resp, got %zu"
 954                                 " bytes\n", vq->iov[out].iov_len);
 955                         break;
 956                 }
 957
 958                 if (unlikely(vq->iov[0].iov_len != sizeof(v_req))) {
 959                         vq_err(vq, "Expecting virtio_scsi_cmd_req, got %zu"
 960                                 " bytes\n", vq->iov[0].iov_len);
 961                         break;
 962                 }
 963                 pr_debug("Calling __copy_from_user: vq->iov[0].iov_base: %p,"
 964                         " len: %zu\n", vq->iov[0].iov_base, sizeof(v_req));
 965                 ret = __copy_from_user(&v_req, vq->iov[0].iov_base,
 966                                 sizeof(v_req));
 967                 if (unlikely(ret)) {
 968                         vq_err(vq, "Faulted on virtio_scsi_cmd_req\n");
 969                         break;
 970                 }
 971
 972                 /* Extract the tpgt */
 973                 target = v_req.lun[1];
 974                 tpg = ACCESS_ONCE(vs_tpg[target]);
 975
 976                 /* Target does not exist, fail the request */
 977                 if (unlikely(!tpg)) {
 978                         vhost_scsi_send_bad_target(vs, vq, head, out);
 979                         continue;
 980                 }
 981
 982                 exp_data_len = 0;
 983                 for (i = 0; i < data_num; i++)
 984                         exp_data_len += vq->iov[data_first + i].iov_len;
 985
 986                 cmd = vhost_scsi_allocate_cmd(vq, tpg, &v_req,
 987                                         exp_data_len, data_direction);
 988                 if (IS_ERR(cmd)) {
 989                         vq_err(vq, "vhost_scsi_allocate_cmd failed %ld\n",
 990                                         PTR_ERR(cmd));
 991                         goto err_cmd;
 992                 }
 993                 pr_debug("Allocated tv_cmd: %p exp_data_len: %d, data_direction"
 994                         ": %d\n", cmd, exp_data_len, data_direction);
 995
 996                 cmd->tvc_vhost = vs;
 997                 cmd->tvc_vq = vq;
 998                 cmd->tvc_resp = vq->iov[out].iov_base;
 999
1000                 /*
1001                  * Copy in the recieved CDB descriptor into cmd->tvc_cdb
1002                  * that will be used by tcm_vhost_new_cmd_map() and down into
1003                  * target_setup_cmd_from_cdb()
1004                  */
1005                 memcpy(cmd->tvc_cdb, v_req.cdb, TCM_VHOST_MAX_CDB_SIZE);
1006                 /*
1007                  * Check that the recieved CDB size does not exceeded our
1008                  * hardcoded max for tcm_vhost
1009                  */
1010                 /* TODO what if cdb was too small for varlen cdb header? */
1011                 if (unlikely(scsi_command_size(cmd->tvc_cdb) >
1012                                         TCM_VHOST_MAX_CDB_SIZE)) {
1013                         vq_err(vq, "Received SCSI CDB with command_size: %d that"
1014                                 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1015                                 scsi_command_size(cmd->tvc_cdb),
1016                                 TCM_VHOST_MAX_CDB_SIZE);
1017                         goto err_free;
1018                 }
1019                 cmd->tvc_lun = ((v_req.lun[2] << 8) | v_req.lun[3]) & 0x3FFF;
1020
1021                 pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n",
1022                         cmd->tvc_cdb[0], cmd->tvc_lun);
1023
1024                 if (data_direction != DMA_NONE) {
1025                         ret = vhost_scsi_map_iov_to_sgl(cmd,
1026                                         &vq->iov[data_first], data_num,
1027                                         data_direction == DMA_TO_DEVICE);
1028                         if (unlikely(ret)) {
1029                                 vq_err(vq, "Failed to map iov to sgl\n");
1030                                 goto err_free;
1031                         }
1032                 }
1033
1034                 /*
1035                  * Save the descriptor from vhost_get_vq_desc() to be used to
1036                  * complete the virtio-scsi request in TCM callback context via
1037                  * tcm_vhost_queue_data_in() and tcm_vhost_queue_status()
1038                  */
1039                 cmd->tvc_vq_desc = head;
1040                 /*
1041                  * Dispatch tv_cmd descriptor for cmwq execution in process
1042                  * context provided by tcm_vhost_workqueue.  This also ensures
1043                  * tv_cmd is executed on the same kworker CPU as this vhost
1044                  * thread to gain positive L2 cache locality effects..
1045                  */
1046                 INIT_WORK(&cmd->work, tcm_vhost_submission_work);
1047                 queue_work(tcm_vhost_workqueue, &cmd->work);
1048         }
1049
1050         mutex_unlock(&vq->mutex);
1051         return;
1052
1053 err_free:
1054         vhost_scsi_free_cmd(cmd);
1055 err_cmd:
1056         vhost_scsi_send_bad_target(vs, vq, head, out);
1057 out:
1058         mutex_unlock(&vq->mutex);
1059 }
1060
1061 static void vhost_scsi_ctl_handle_kick(struct vhost_work *work)
1062 {
1063         pr_debug("%s: The handling func for control queue.\n", __func__);
1064 }
1065
1066 static void
1067 tcm_vhost_send_evt(struct vhost_scsi *vs,
1068                    struct tcm_vhost_tpg *tpg,
1069                    struct se_lun *lun,
1070                    u32 event,
1071                    u32 reason)
1072 {
1073         struct tcm_vhost_evt *evt;
1074
1075         evt = tcm_vhost_allocate_evt(vs, event, reason);
1076         if (!evt)
1077                 return;
1078
1079         if (tpg && lun) {
1080                 /* TODO: share lun setup code with virtio-scsi.ko */
1081                 /*
1082                  * Note: evt->event is zeroed when we allocate it and
1083                  * lun[4-7] need to be zero according to virtio-scsi spec.
1084                  */
1085                 evt->event.lun[0] = 0x01;
1086                 evt->event.lun[1] = tpg->tport_tpgt & 0xFF;
1087                 if (lun->unpacked_lun >= 256)
1088                         evt->event.lun[2] = lun->unpacked_lun >> 8 | 0x40 ;
1089                 evt->event.lun[3] = lun->unpacked_lun & 0xFF;
1090         }
1091
1092         llist_add(&evt->list, &vs->vs_event_list);
1093         vhost_work_queue(&vs->dev, &vs->vs_event_work);
1094 }
1095
1096 static void vhost_scsi_evt_handle_kick(struct vhost_work *work)
1097 {
1098         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1099                                                 poll.work);
1100         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1101
1102         mutex_lock(&vq->mutex);
1103         if (!vq->private_data)
1104                 goto out;
1105
1106         if (vs->vs_events_missed)
1107                 tcm_vhost_send_evt(vs, NULL, NULL, VIRTIO_SCSI_T_NO_EVENT, 0);
1108 out:
1109         mutex_unlock(&vq->mutex);
1110 }
1111
1112 static void vhost_scsi_handle_kick(struct vhost_work *work)
1113 {
1114         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1115                                                 poll.work);
1116         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1117
1118         vhost_scsi_handle_vq(vs, vq);
1119 }
1120
1121 static void vhost_scsi_flush_vq(struct vhost_scsi *vs, int index)
1122 {
1123         vhost_poll_flush(&vs->vqs[index].vq.poll);
1124 }
1125
1126 /* Callers must hold dev mutex */
1127 static void vhost_scsi_flush(struct vhost_scsi *vs)
1128 {
1129         struct vhost_scsi_inflight *old_inflight[VHOST_SCSI_MAX_VQ];
1130         int i;
1131
1132         /* Init new inflight and remember the old inflight */
1133         tcm_vhost_init_inflight(vs, old_inflight);
1134
1135         /*
1136          * The inflight->kref was initialized to 1. We decrement it here to
1137          * indicate the start of the flush operation so that it will reach 0
1138          * when all the reqs are finished.
1139          */
1140         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1141                 kref_put(&old_inflight[i]->kref, tcm_vhost_done_inflight);
1142
1143         /* Flush both the vhost poll and vhost work */
1144         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1145                 vhost_scsi_flush_vq(vs, i);
1146         vhost_work_flush(&vs->dev, &vs->vs_completion_work);
1147         vhost_work_flush(&vs->dev, &vs->vs_event_work);
1148
1149         /* Wait for all reqs issued before the flush to be finished */
1150         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1151                 wait_for_completion(&old_inflight[i]->comp);
1152 }
1153
1154 /*
1155  * Called from vhost_scsi_ioctl() context to walk the list of available
1156  * tcm_vhost_tpg with an active struct tcm_vhost_nexus
1157  *
1158  *  The lock nesting rule is:
1159  *    tcm_vhost_mutex -> vs->dev.mutex -> tpg->tv_tpg_mutex -> vq->mutex
1160  */
1161 static int
1162 vhost_scsi_set_endpoint(struct vhost_scsi *vs,
1163                         struct vhost_scsi_target *t)
1164 {
1165         struct tcm_vhost_tport *tv_tport;
1166         struct tcm_vhost_tpg *tpg;
1167         struct tcm_vhost_tpg **vs_tpg;
1168         struct vhost_virtqueue *vq;
1169         int index, ret, i, len;
1170         bool match = false;
1171
1172         mutex_lock(&tcm_vhost_mutex);
1173         mutex_lock(&vs->dev.mutex);
1174
1175         /* Verify that ring has been setup correctly. */
1176         for (index = 0; index < vs->dev.nvqs; ++index) {
1177                 /* Verify that ring has been setup correctly. */
1178                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1179                         ret = -EFAULT;
1180                         goto out;
1181                 }
1182         }
1183
1184         len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET;
1185         vs_tpg = kzalloc(len, GFP_KERNEL);
1186         if (!vs_tpg) {
1187                 ret = -ENOMEM;
1188                 goto out;
1189         }
1190         if (vs->vs_tpg)
1191                 memcpy(vs_tpg, vs->vs_tpg, len);
1192
1193         list_for_each_entry(tpg, &tcm_vhost_list, tv_tpg_list) {
1194                 mutex_lock(&tpg->tv_tpg_mutex);
1195                 if (!tpg->tpg_nexus) {
1196                         mutex_unlock(&tpg->tv_tpg_mutex);
1197                         continue;
1198                 }
1199                 if (tpg->tv_tpg_vhost_count != 0) {
1200                         mutex_unlock(&tpg->tv_tpg_mutex);
1201                         continue;
1202                 }
1203                 tv_tport = tpg->tport;
1204
1205                 if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1206                         if (vs->vs_tpg && vs->vs_tpg[tpg->tport_tpgt]) {
1207                                 kfree(vs_tpg);
1208                                 mutex_unlock(&tpg->tv_tpg_mutex);
1209                                 ret = -EEXIST;
1210                                 goto out;
1211                         }
1212                         tpg->tv_tpg_vhost_count++;
1213                         tpg->vhost_scsi = vs;
1214                         vs_tpg[tpg->tport_tpgt] = tpg;
1215                         smp_mb__after_atomic_inc();
1216                         match = true;
1217                 }
1218                 mutex_unlock(&tpg->tv_tpg_mutex);
1219         }
1220
1221         if (match) {
1222                 memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
1223                        sizeof(vs->vs_vhost_wwpn));
1224                 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1225                         vq = &vs->vqs[i].vq;
1226                         mutex_lock(&vq->mutex);
1227                         vq->private_data = vs_tpg;
1228                         vhost_init_used(vq);
1229                         mutex_unlock(&vq->mutex);
1230                 }
1231                 ret = 0;
1232         } else {
1233                 ret = -EEXIST;
1234         }
1235
1236         /*
1237          * Act as synchronize_rcu to make sure access to
1238          * old vs->vs_tpg is finished.
1239          */
1240         vhost_scsi_flush(vs);
1241         kfree(vs->vs_tpg);
1242         vs->vs_tpg = vs_tpg;
1243
1244 out:
1245         mutex_unlock(&vs->dev.mutex);
1246         mutex_unlock(&tcm_vhost_mutex);
1247         return ret;
1248 }
1249
1250 static int
1251 vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
1252                           struct vhost_scsi_target *t)
1253 {
1254         struct tcm_vhost_tport *tv_tport;
1255         struct tcm_vhost_tpg *tpg;
1256         struct vhost_virtqueue *vq;
1257         bool match = false;
1258         int index, ret, i;
1259         u8 target;
1260
1261         mutex_lock(&tcm_vhost_mutex);
1262         mutex_lock(&vs->dev.mutex);
1263         /* Verify that ring has been setup correctly. */
1264         for (index = 0; index < vs->dev.nvqs; ++index) {
1265                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1266                         ret = -EFAULT;
1267                         goto err_dev;
1268                 }
1269         }
1270
1271         if (!vs->vs_tpg) {
1272                 ret = 0;
1273                 goto err_dev;
1274         }
1275
1276         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1277                 target = i;
1278                 tpg = vs->vs_tpg[target];
1279                 if (!tpg)
1280                         continue;
1281
1282                 mutex_lock(&tpg->tv_tpg_mutex);
1283                 tv_tport = tpg->tport;
1284                 if (!tv_tport) {
1285                         ret = -ENODEV;
1286                         goto err_tpg;
1287                 }
1288
1289                 if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1290                         pr_warn("tv_tport->tport_name: %s, tpg->tport_tpgt: %hu"
1291                                 " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
1292                                 tv_tport->tport_name, tpg->tport_tpgt,
1293                                 t->vhost_wwpn, t->vhost_tpgt);
1294                         ret = -EINVAL;
1295                         goto err_tpg;
1296                 }
1297                 tpg->tv_tpg_vhost_count--;
1298                 tpg->vhost_scsi = NULL;
1299                 vs->vs_tpg[target] = NULL;
1300                 match = true;
1301                 mutex_unlock(&tpg->tv_tpg_mutex);
1302         }
1303         if (match) {
1304                 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1305                         vq = &vs->vqs[i].vq;
1306                         mutex_lock(&vq->mutex);
1307                         vq->private_data = NULL;
1308                         mutex_unlock(&vq->mutex);
1309                 }
1310         }
1311         /*
1312          * Act as synchronize_rcu to make sure access to
1313          * old vs->vs_tpg is finished.
1314          */
1315         vhost_scsi_flush(vs);
1316         kfree(vs->vs_tpg);
1317         vs->vs_tpg = NULL;
1318         WARN_ON(vs->vs_events_nr);
1319         mutex_unlock(&vs->dev.mutex);
1320         mutex_unlock(&tcm_vhost_mutex);
1321         return 0;
1322
1323 err_tpg:
1324         mutex_unlock(&tpg->tv_tpg_mutex);
1325 err_dev:
1326         mutex_unlock(&vs->dev.mutex);
1327         mutex_unlock(&tcm_vhost_mutex);
1328         return ret;
1329 }
1330
1331 static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features)
1332 {
1333         if (features & ~VHOST_SCSI_FEATURES)
1334                 return -EOPNOTSUPP;
1335
1336         mutex_lock(&vs->dev.mutex);
1337         if ((features & (1 << VHOST_F_LOG_ALL)) &&
1338             !vhost_log_access_ok(&vs->dev)) {
1339                 mutex_unlock(&vs->dev.mutex);
1340                 return -EFAULT;
1341         }
1342         vs->dev.acked_features = features;
1343         smp_wmb();
1344         vhost_scsi_flush(vs);
1345         mutex_unlock(&vs->dev.mutex);
1346         return 0;
1347 }
1348
1349 static int vhost_scsi_open(struct inode *inode, struct file *f)
1350 {
1351         struct vhost_scsi *vs;
1352         struct vhost_virtqueue **vqs;
1353         int r, i;
1354
1355         vs = kzalloc(sizeof(*vs), GFP_KERNEL);
1356         if (!vs)
1357                 return -ENOMEM;
1358
1359         vqs = kmalloc(VHOST_SCSI_MAX_VQ * sizeof(*vqs), GFP_KERNEL);
1360         if (!vqs) {
1361                 kfree(vs);
1362                 return -ENOMEM;
1363         }
1364
1365         vhost_work_init(&vs->vs_completion_work, vhost_scsi_complete_cmd_work);
1366         vhost_work_init(&vs->vs_event_work, tcm_vhost_evt_work);
1367
1368         vs->vs_events_nr = 0;
1369         vs->vs_events_missed = false;
1370
1371         vqs[VHOST_SCSI_VQ_CTL] = &vs->vqs[VHOST_SCSI_VQ_CTL].vq;
1372         vqs[VHOST_SCSI_VQ_EVT] = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1373         vs->vqs[VHOST_SCSI_VQ_CTL].vq.handle_kick = vhost_scsi_ctl_handle_kick;
1374         vs->vqs[VHOST_SCSI_VQ_EVT].vq.handle_kick = vhost_scsi_evt_handle_kick;
1375         for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++) {
1376                 vqs[i] = &vs->vqs[i].vq;
1377                 vs->vqs[i].vq.handle_kick = vhost_scsi_handle_kick;
1378         }
1379         r = vhost_dev_init(&vs->dev, vqs, VHOST_SCSI_MAX_VQ);
1380
1381         tcm_vhost_init_inflight(vs, NULL);
1382
1383         if (r < 0) {
1384                 kfree(vqs);
1385                 kfree(vs);
1386                 return r;
1387         }
1388
1389         f->private_data = vs;
1390         return 0;
1391 }
1392
1393 static int vhost_scsi_release(struct inode *inode, struct file *f)
1394 {
1395         struct vhost_scsi *vs = f->private_data;
1396         struct vhost_scsi_target t;
1397
1398         mutex_lock(&vs->dev.mutex);
1399         memcpy(t.vhost_wwpn, vs->vs_vhost_wwpn, sizeof(t.vhost_wwpn));
1400         mutex_unlock(&vs->dev.mutex);
1401         vhost_scsi_clear_endpoint(vs, &t);
1402         vhost_dev_stop(&vs->dev);
1403         vhost_dev_cleanup(&vs->dev, false);
1404         /* Jobs can re-queue themselves in evt kick handler. Do extra flush. */
1405         vhost_scsi_flush(vs);
1406         kfree(vs->dev.vqs);
1407         kfree(vs);
1408         return 0;
1409 }
1410
1411 static long
1412 vhost_scsi_ioctl(struct file *f,
1413                  unsigned int ioctl,
1414                  unsigned long arg)
1415 {
1416         struct vhost_scsi *vs = f->private_data;
1417         struct vhost_scsi_target backend;
1418         void __user *argp = (void __user *)arg;
1419         u64 __user *featurep = argp;
1420         u32 __user *eventsp = argp;
1421         u32 events_missed;
1422         u64 features;
1423         int r, abi_version = VHOST_SCSI_ABI_VERSION;
1424         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1425
1426         switch (ioctl) {
1427         case VHOST_SCSI_SET_ENDPOINT:
1428                 if (copy_from_user(&backend, argp, sizeof backend))
1429                         return -EFAULT;
1430                 if (backend.reserved != 0)
1431                         return -EOPNOTSUPP;
1432
1433                 return vhost_scsi_set_endpoint(vs, &backend);
1434         case VHOST_SCSI_CLEAR_ENDPOINT:
1435                 if (copy_from_user(&backend, argp, sizeof backend))
1436                         return -EFAULT;
1437                 if (backend.reserved != 0)
1438                         return -EOPNOTSUPP;
1439
1440                 return vhost_scsi_clear_endpoint(vs, &backend);
1441         case VHOST_SCSI_GET_ABI_VERSION:
1442                 if (copy_to_user(argp, &abi_version, sizeof abi_version))
1443                         return -EFAULT;
1444                 return 0;
1445         case VHOST_SCSI_SET_EVENTS_MISSED:
1446                 if (get_user(events_missed, eventsp))
1447                         return -EFAULT;
1448                 mutex_lock(&vq->mutex);
1449                 vs->vs_events_missed = events_missed;
1450                 mutex_unlock(&vq->mutex);
1451                 return 0;
1452         case VHOST_SCSI_GET_EVENTS_MISSED:
1453                 mutex_lock(&vq->mutex);
1454                 events_missed = vs->vs_events_missed;
1455                 mutex_unlock(&vq->mutex);
1456                 if (put_user(events_missed, eventsp))
1457                         return -EFAULT;
1458                 return 0;
1459         case VHOST_GET_FEATURES:
1460                 features = VHOST_SCSI_FEATURES;
1461                 if (copy_to_user(featurep, &features, sizeof features))
1462                         return -EFAULT;
1463                 return 0;
1464         case VHOST_SET_FEATURES:
1465                 if (copy_from_user(&features, featurep, sizeof features))
1466                         return -EFAULT;
1467                 return vhost_scsi_set_features(vs, features);
1468         default:
1469                 mutex_lock(&vs->dev.mutex);
1470                 r = vhost_dev_ioctl(&vs->dev, ioctl, argp);
1471                 /* TODO: flush backend after dev ioctl. */
1472                 if (r == -ENOIOCTLCMD)
1473                         r = vhost_vring_ioctl(&vs->dev, ioctl, argp);
1474                 mutex_unlock(&vs->dev.mutex);
1475                 return r;
1476         }
1477 }
1478
1479 #ifdef CONFIG_COMPAT
1480 static long vhost_scsi_compat_ioctl(struct file *f, unsigned int ioctl,
1481                                 unsigned long arg)
1482 {
1483         return vhost_scsi_ioctl(f, ioctl, (unsigned long)compat_ptr(arg));
1484 }
1485 #endif
1486
1487 static const struct file_operations vhost_scsi_fops = {
1488         .owner          = THIS_MODULE,
1489         .release        = vhost_scsi_release,
1490         .unlocked_ioctl = vhost_scsi_ioctl,
1491 #ifdef CONFIG_COMPAT
1492         .compat_ioctl   = vhost_scsi_compat_ioctl,
1493 #endif
1494         .open           = vhost_scsi_open,
1495         .llseek         = noop_llseek,
1496 };
1497
1498 static struct miscdevice vhost_scsi_misc = {
1499         MISC_DYNAMIC_MINOR,
1500         "vhost-scsi",
1501         &vhost_scsi_fops,
1502 };
1503
1504 static int __init vhost_scsi_register(void)
1505 {
1506         return misc_register(&vhost_scsi_misc);
1507 }
1508
1509 static int vhost_scsi_deregister(void)
1510 {
1511         return misc_deregister(&vhost_scsi_misc);
1512 }
1513
1514 static char *tcm_vhost_dump_proto_id(struct tcm_vhost_tport *tport)
1515 {
1516         switch (tport->tport_proto_id) {
1517         case SCSI_PROTOCOL_SAS:
1518                 return "SAS";
1519         case SCSI_PROTOCOL_FCP:
1520                 return "FCP";
1521         case SCSI_PROTOCOL_ISCSI:
1522                 return "iSCSI";
1523         default:
1524                 break;
1525         }
1526
1527         return "Unknown";
1528 }
1529
1530 static void
1531 tcm_vhost_do_plug(struct tcm_vhost_tpg *tpg,
1532                   struct se_lun *lun, bool plug)
1533 {
1534
1535         struct vhost_scsi *vs = tpg->vhost_scsi;
1536         struct vhost_virtqueue *vq;
1537         u32 reason;
1538
1539         if (!vs)
1540                 return;
1541
1542         mutex_lock(&vs->dev.mutex);
1543         if (!vhost_has_feature(&vs->dev, VIRTIO_SCSI_F_HOTPLUG)) {
1544                 mutex_unlock(&vs->dev.mutex);
1545                 return;
1546         }
1547
1548         if (plug)
1549                 reason = VIRTIO_SCSI_EVT_RESET_RESCAN;
1550         else
1551                 reason = VIRTIO_SCSI_EVT_RESET_REMOVED;
1552
1553         vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1554         mutex_lock(&vq->mutex);
1555         tcm_vhost_send_evt(vs, tpg, lun,
1556                         VIRTIO_SCSI_T_TRANSPORT_RESET, reason);
1557         mutex_unlock(&vq->mutex);
1558         mutex_unlock(&vs->dev.mutex);
1559 }
1560
1561 static void tcm_vhost_hotplug(struct tcm_vhost_tpg *tpg, struct se_lun *lun)
1562 {
1563         tcm_vhost_do_plug(tpg, lun, true);
1564 }
1565
1566 static void tcm_vhost_hotunplug(struct tcm_vhost_tpg *tpg, struct se_lun *lun)
1567 {
1568         tcm_vhost_do_plug(tpg, lun, false);
1569 }
1570
1571 static int tcm_vhost_port_link(struct se_portal_group *se_tpg,
1572                                struct se_lun *lun)
1573 {
1574         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1575                                 struct tcm_vhost_tpg, se_tpg);
1576
1577         mutex_lock(&tcm_vhost_mutex);
1578
1579         mutex_lock(&tpg->tv_tpg_mutex);
1580         tpg->tv_tpg_port_count++;
1581         mutex_unlock(&tpg->tv_tpg_mutex);
1582
1583         tcm_vhost_hotplug(tpg, lun);
1584
1585         mutex_unlock(&tcm_vhost_mutex);
1586
1587         return 0;
1588 }
1589
1590 static void tcm_vhost_port_unlink(struct se_portal_group *se_tpg,
1591                                   struct se_lun *lun)
1592 {
1593         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1594                                 struct tcm_vhost_tpg, se_tpg);
1595
1596         mutex_lock(&tcm_vhost_mutex);
1597
1598         mutex_lock(&tpg->tv_tpg_mutex);
1599         tpg->tv_tpg_port_count--;
1600         mutex_unlock(&tpg->tv_tpg_mutex);
1601
1602         tcm_vhost_hotunplug(tpg, lun);
1603
1604         mutex_unlock(&tcm_vhost_mutex);
1605 }
1606
1607 static struct se_node_acl *
1608 tcm_vhost_make_nodeacl(struct se_portal_group *se_tpg,
1609                        struct config_group *group,
1610                        const char *name)
1611 {
1612         struct se_node_acl *se_nacl, *se_nacl_new;
1613         struct tcm_vhost_nacl *nacl;
1614         u64 wwpn = 0;
1615         u32 nexus_depth;
1616
1617         /* tcm_vhost_parse_wwn(name, &wwpn, 1) < 0)
1618                 return ERR_PTR(-EINVAL); */
1619         se_nacl_new = tcm_vhost_alloc_fabric_acl(se_tpg);
1620         if (!se_nacl_new)
1621                 return ERR_PTR(-ENOMEM);
1622
1623         nexus_depth = 1;
1624         /*
1625          * se_nacl_new may be released by core_tpg_add_initiator_node_acl()
1626          * when converting a NodeACL from demo mode -> explict
1627          */
1628         se_nacl = core_tpg_add_initiator_node_acl(se_tpg, se_nacl_new,
1629                                 name, nexus_depth);
1630         if (IS_ERR(se_nacl)) {
1631                 tcm_vhost_release_fabric_acl(se_tpg, se_nacl_new);
1632                 return se_nacl;
1633         }
1634         /*
1635          * Locate our struct tcm_vhost_nacl and set the FC Nport WWPN
1636          */
1637         nacl = container_of(se_nacl, struct tcm_vhost_nacl, se_node_acl);
1638         nacl->iport_wwpn = wwpn;
1639
1640         return se_nacl;
1641 }
1642
1643 static void tcm_vhost_drop_nodeacl(struct se_node_acl *se_acl)
1644 {
1645         struct tcm_vhost_nacl *nacl = container_of(se_acl,
1646                                 struct tcm_vhost_nacl, se_node_acl);
1647         core_tpg_del_initiator_node_acl(se_acl->se_tpg, se_acl, 1);
1648         kfree(nacl);
1649 }
1650
1651 static int tcm_vhost_make_nexus(struct tcm_vhost_tpg *tpg,
1652                                 const char *name)
1653 {
1654         struct se_portal_group *se_tpg;
1655         struct tcm_vhost_nexus *tv_nexus;
1656
1657         mutex_lock(&tpg->tv_tpg_mutex);
1658         if (tpg->tpg_nexus) {
1659                 mutex_unlock(&tpg->tv_tpg_mutex);
1660                 pr_debug("tpg->tpg_nexus already exists\n");
1661                 return -EEXIST;
1662         }
1663         se_tpg = &tpg->se_tpg;
1664
1665         tv_nexus = kzalloc(sizeof(struct tcm_vhost_nexus), GFP_KERNEL);
1666         if (!tv_nexus) {
1667                 mutex_unlock(&tpg->tv_tpg_mutex);
1668                 pr_err("Unable to allocate struct tcm_vhost_nexus\n");
1669                 return -ENOMEM;
1670         }
1671         /*
1672          *  Initialize the struct se_session pointer
1673          */
1674         tv_nexus->tvn_se_sess = transport_init_session();
1675         if (IS_ERR(tv_nexus->tvn_se_sess)) {
1676                 mutex_unlock(&tpg->tv_tpg_mutex);
1677                 kfree(tv_nexus);
1678                 return -ENOMEM;
1679         }
1680         /*
1681          * Since we are running in 'demo mode' this call with generate a
1682          * struct se_node_acl for the tcm_vhost struct se_portal_group with
1683          * the SCSI Initiator port name of the passed configfs group 'name'.
1684          */
1685         tv_nexus->tvn_se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
1686                                 se_tpg, (unsigned char *)name);
1687         if (!tv_nexus->tvn_se_sess->se_node_acl) {
1688                 mutex_unlock(&tpg->tv_tpg_mutex);
1689                 pr_debug("core_tpg_check_initiator_node_acl() failed"
1690                                 " for %s\n", name);
1691                 transport_free_session(tv_nexus->tvn_se_sess);
1692                 kfree(tv_nexus);
1693                 return -ENOMEM;
1694         }
1695         /*
1696          * Now register the TCM vhost virtual I_T Nexus as active with the
1697          * call to __transport_register_session()
1698          */
1699         __transport_register_session(se_tpg, tv_nexus->tvn_se_sess->se_node_acl,
1700                         tv_nexus->tvn_se_sess, tv_nexus);
1701         tpg->tpg_nexus = tv_nexus;
1702
1703         mutex_unlock(&tpg->tv_tpg_mutex);
1704         return 0;
1705 }
1706
1707 static int tcm_vhost_drop_nexus(struct tcm_vhost_tpg *tpg)
1708 {
1709         struct se_session *se_sess;
1710         struct tcm_vhost_nexus *tv_nexus;
1711
1712         mutex_lock(&tpg->tv_tpg_mutex);
1713         tv_nexus = tpg->tpg_nexus;
1714         if (!tv_nexus) {
1715                 mutex_unlock(&tpg->tv_tpg_mutex);
1716                 return -ENODEV;
1717         }
1718
1719         se_sess = tv_nexus->tvn_se_sess;
1720         if (!se_sess) {
1721                 mutex_unlock(&tpg->tv_tpg_mutex);
1722                 return -ENODEV;
1723         }
1724
1725         if (tpg->tv_tpg_port_count != 0) {
1726                 mutex_unlock(&tpg->tv_tpg_mutex);
1727                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
1728                         " active TPG port count: %d\n",
1729                         tpg->tv_tpg_port_count);
1730                 return -EBUSY;
1731         }
1732
1733         if (tpg->tv_tpg_vhost_count != 0) {
1734                 mutex_unlock(&tpg->tv_tpg_mutex);
1735                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
1736                         " active TPG vhost count: %d\n",
1737                         tpg->tv_tpg_vhost_count);
1738                 return -EBUSY;
1739         }
1740
1741         pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated"
1742                 " %s Initiator Port: %s\n", tcm_vhost_dump_proto_id(tpg->tport),
1743                 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1744         /*
1745          * Release the SCSI I_T Nexus to the emulated vhost Target Port
1746          */
1747         transport_deregister_session(tv_nexus->tvn_se_sess);
1748         tpg->tpg_nexus = NULL;
1749         mutex_unlock(&tpg->tv_tpg_mutex);
1750
1751         kfree(tv_nexus);
1752         return 0;
1753 }
1754
1755 static ssize_t tcm_vhost_tpg_show_nexus(struct se_portal_group *se_tpg,
1756                                         char *page)
1757 {
1758         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1759                                 struct tcm_vhost_tpg, se_tpg);
1760         struct tcm_vhost_nexus *tv_nexus;
1761         ssize_t ret;
1762
1763         mutex_lock(&tpg->tv_tpg_mutex);
1764         tv_nexus = tpg->tpg_nexus;
1765         if (!tv_nexus) {
1766                 mutex_unlock(&tpg->tv_tpg_mutex);
1767                 return -ENODEV;
1768         }
1769         ret = snprintf(page, PAGE_SIZE, "%s\n",
1770                         tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1771         mutex_unlock(&tpg->tv_tpg_mutex);
1772
1773         return ret;
1774 }
1775
1776 static ssize_t tcm_vhost_tpg_store_nexus(struct se_portal_group *se_tpg,
1777                                          const char *page,
1778                                          size_t count)
1779 {
1780         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1781                                 struct tcm_vhost_tpg, se_tpg);
1782         struct tcm_vhost_tport *tport_wwn = tpg->tport;
1783         unsigned char i_port[TCM_VHOST_NAMELEN], *ptr, *port_ptr;
1784         int ret;
1785         /*
1786          * Shutdown the active I_T nexus if 'NULL' is passed..
1787          */
1788         if (!strncmp(page, "NULL", 4)) {
1789                 ret = tcm_vhost_drop_nexus(tpg);
1790                 return (!ret) ? count : ret;
1791         }
1792         /*
1793          * Otherwise make sure the passed virtual Initiator port WWN matches
1794          * the fabric protocol_id set in tcm_vhost_make_tport(), and call
1795          * tcm_vhost_make_nexus().
1796          */
1797         if (strlen(page) >= TCM_VHOST_NAMELEN) {
1798                 pr_err("Emulated NAA Sas Address: %s, exceeds"
1799                                 " max: %d\n", page, TCM_VHOST_NAMELEN);
1800                 return -EINVAL;
1801         }
1802         snprintf(&i_port[0], TCM_VHOST_NAMELEN, "%s", page);
1803
1804         ptr = strstr(i_port, "naa.");
1805         if (ptr) {
1806                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
1807                         pr_err("Passed SAS Initiator Port %s does not"
1808                                 " match target port protoid: %s\n", i_port,
1809                                 tcm_vhost_dump_proto_id(tport_wwn));
1810                         return -EINVAL;
1811                 }
1812                 port_ptr = &i_port[0];
1813                 goto check_newline;
1814         }
1815         ptr = strstr(i_port, "fc.");
1816         if (ptr) {
1817                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
1818                         pr_err("Passed FCP Initiator Port %s does not"
1819                                 " match target port protoid: %s\n", i_port,
1820                                 tcm_vhost_dump_proto_id(tport_wwn));
1821                         return -EINVAL;
1822                 }
1823                 port_ptr = &i_port[3]; /* Skip over "fc." */
1824                 goto check_newline;
1825         }
1826         ptr = strstr(i_port, "iqn.");
1827         if (ptr) {
1828                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
1829                         pr_err("Passed iSCSI Initiator Port %s does not"
1830                                 " match target port protoid: %s\n", i_port,
1831                                 tcm_vhost_dump_proto_id(tport_wwn));
1832                         return -EINVAL;
1833                 }
1834                 port_ptr = &i_port[0];
1835                 goto check_newline;
1836         }
1837         pr_err("Unable to locate prefix for emulated Initiator Port:"
1838                         " %s\n", i_port);
1839         return -EINVAL;
1840         /*
1841          * Clear any trailing newline for the NAA WWN
1842          */
1843 check_newline:
1844         if (i_port[strlen(i_port)-1] == '\n')
1845                 i_port[strlen(i_port)-1] = '\0';
1846
1847         ret = tcm_vhost_make_nexus(tpg, port_ptr);
1848         if (ret < 0)
1849                 return ret;
1850
1851         return count;
1852 }
1853
1854 TF_TPG_BASE_ATTR(tcm_vhost, nexus, S_IRUGO | S_IWUSR);
1855
1856 static struct configfs_attribute *tcm_vhost_tpg_attrs[] = {
1857         &tcm_vhost_tpg_nexus.attr,
1858         NULL,
1859 };
1860
1861 static struct se_portal_group *
1862 tcm_vhost_make_tpg(struct se_wwn *wwn,
1863                    struct config_group *group,
1864                    const char *name)
1865 {
1866         struct tcm_vhost_tport *tport = container_of(wwn,
1867                         struct tcm_vhost_tport, tport_wwn);
1868
1869         struct tcm_vhost_tpg *tpg;
1870         unsigned long tpgt;
1871         int ret;
1872
1873         if (strstr(name, "tpgt_") != name)
1874                 return ERR_PTR(-EINVAL);
1875         if (kstrtoul(name + 5, 10, &tpgt) || tpgt > UINT_MAX)
1876                 return ERR_PTR(-EINVAL);
1877
1878         tpg = kzalloc(sizeof(struct tcm_vhost_tpg), GFP_KERNEL);
1879         if (!tpg) {
1880                 pr_err("Unable to allocate struct tcm_vhost_tpg");
1881                 return ERR_PTR(-ENOMEM);
1882         }
1883         mutex_init(&tpg->tv_tpg_mutex);
1884         INIT_LIST_HEAD(&tpg->tv_tpg_list);
1885         tpg->tport = tport;
1886         tpg->tport_tpgt = tpgt;
1887
1888         ret = core_tpg_register(&tcm_vhost_fabric_configfs->tf_ops, wwn,
1889                                 &tpg->se_tpg, tpg, TRANSPORT_TPG_TYPE_NORMAL);
1890         if (ret < 0) {
1891                 kfree(tpg);
1892                 return NULL;
1893         }
1894         mutex_lock(&tcm_vhost_mutex);
1895         list_add_tail(&tpg->tv_tpg_list, &tcm_vhost_list);
1896         mutex_unlock(&tcm_vhost_mutex);
1897
1898         return &tpg->se_tpg;
1899 }
1900
1901 static void tcm_vhost_drop_tpg(struct se_portal_group *se_tpg)
1902 {
1903         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1904                                 struct tcm_vhost_tpg, se_tpg);
1905
1906         mutex_lock(&tcm_vhost_mutex);
1907         list_del(&tpg->tv_tpg_list);
1908         mutex_unlock(&tcm_vhost_mutex);
1909         /*
1910          * Release the virtual I_T Nexus for this vhost TPG
1911          */
1912         tcm_vhost_drop_nexus(tpg);
1913         /*
1914          * Deregister the se_tpg from TCM..
1915          */
1916         core_tpg_deregister(se_tpg);
1917         kfree(tpg);
1918 }
1919
1920 static struct se_wwn *
1921 tcm_vhost_make_tport(struct target_fabric_configfs *tf,
1922                      struct config_group *group,
1923                      const char *name)
1924 {
1925         struct tcm_vhost_tport *tport;
1926         char *ptr;
1927         u64 wwpn = 0;
1928         int off = 0;
1929
1930         /* if (tcm_vhost_parse_wwn(name, &wwpn, 1) < 0)
1931                 return ERR_PTR(-EINVAL); */
1932
1933         tport = kzalloc(sizeof(struct tcm_vhost_tport), GFP_KERNEL);
1934         if (!tport) {
1935                 pr_err("Unable to allocate struct tcm_vhost_tport");
1936                 return ERR_PTR(-ENOMEM);
1937         }
1938         tport->tport_wwpn = wwpn;
1939         /*
1940          * Determine the emulated Protocol Identifier and Target Port Name
1941          * based on the incoming configfs directory name.
1942          */
1943         ptr = strstr(name, "naa.");
1944         if (ptr) {
1945                 tport->tport_proto_id = SCSI_PROTOCOL_SAS;
1946                 goto check_len;
1947         }
1948         ptr = strstr(name, "fc.");
1949         if (ptr) {
1950                 tport->tport_proto_id = SCSI_PROTOCOL_FCP;
1951                 off = 3; /* Skip over "fc." */
1952                 goto check_len;
1953         }
1954         ptr = strstr(name, "iqn.");
1955         if (ptr) {
1956                 tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
1957                 goto check_len;
1958         }
1959
1960         pr_err("Unable to locate prefix for emulated Target Port:"
1961                         " %s\n", name);
1962         kfree(tport);
1963         return ERR_PTR(-EINVAL);
1964
1965 check_len:
1966         if (strlen(name) >= TCM_VHOST_NAMELEN) {
1967                 pr_err("Emulated %s Address: %s, exceeds"
1968                         " max: %d\n", name, tcm_vhost_dump_proto_id(tport),
1969                         TCM_VHOST_NAMELEN);
1970                 kfree(tport);
1971                 return ERR_PTR(-EINVAL);
1972         }
1973         snprintf(&tport->tport_name[0], TCM_VHOST_NAMELEN, "%s", &name[off]);
1974
1975         pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target"
1976                 " %s Address: %s\n", tcm_vhost_dump_proto_id(tport), name);
1977
1978         return &tport->tport_wwn;
1979 }
1980
1981 static void tcm_vhost_drop_tport(struct se_wwn *wwn)
1982 {
1983         struct tcm_vhost_tport *tport = container_of(wwn,
1984                                 struct tcm_vhost_tport, tport_wwn);
1985
1986         pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target"
1987                 " %s Address: %s\n", tcm_vhost_dump_proto_id(tport),
1988                 tport->tport_name);
1989
1990         kfree(tport);
1991 }
1992
1993 static ssize_t
1994 tcm_vhost_wwn_show_attr_version(struct target_fabric_configfs *tf,
1995                                 char *page)
1996 {
1997         return sprintf(page, "TCM_VHOST fabric module %s on %s/%s"
1998                 "on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname,
1999                 utsname()->machine);
2000 }
2001
2002 TF_WWN_ATTR_RO(tcm_vhost, version);
2003
2004 static struct configfs_attribute *tcm_vhost_wwn_attrs[] = {
2005         &tcm_vhost_wwn_version.attr,
2006         NULL,
2007 };
2008
2009 static struct target_core_fabric_ops tcm_vhost_ops = {
2010         .get_fabric_name                = tcm_vhost_get_fabric_name,
2011         .get_fabric_proto_ident         = tcm_vhost_get_fabric_proto_ident,
2012         .tpg_get_wwn                    = tcm_vhost_get_fabric_wwn,
2013         .tpg_get_tag                    = tcm_vhost_get_tag,
2014         .tpg_get_default_depth          = tcm_vhost_get_default_depth,
2015         .tpg_get_pr_transport_id        = tcm_vhost_get_pr_transport_id,
2016         .tpg_get_pr_transport_id_len    = tcm_vhost_get_pr_transport_id_len,
2017         .tpg_parse_pr_out_transport_id  = tcm_vhost_parse_pr_out_transport_id,
2018         .tpg_check_demo_mode            = tcm_vhost_check_true,
2019         .tpg_check_demo_mode_cache      = tcm_vhost_check_true,
2020         .tpg_check_demo_mode_write_protect = tcm_vhost_check_false,
2021         .tpg_check_prod_mode_write_protect = tcm_vhost_check_false,
2022         .tpg_alloc_fabric_acl           = tcm_vhost_alloc_fabric_acl,
2023         .tpg_release_fabric_acl         = tcm_vhost_release_fabric_acl,
2024         .tpg_get_inst_index             = tcm_vhost_tpg_get_inst_index,
2025         .release_cmd                    = tcm_vhost_release_cmd,
2026         .shutdown_session               = tcm_vhost_shutdown_session,
2027         .close_session                  = tcm_vhost_close_session,
2028         .sess_get_index                 = tcm_vhost_sess_get_index,
2029         .sess_get_initiator_sid         = NULL,
2030         .write_pending                  = tcm_vhost_write_pending,
2031         .write_pending_status           = tcm_vhost_write_pending_status,
2032         .set_default_node_attributes    = tcm_vhost_set_default_node_attrs,
2033         .get_task_tag                   = tcm_vhost_get_task_tag,
2034         .get_cmd_state                  = tcm_vhost_get_cmd_state,
2035         .queue_data_in                  = tcm_vhost_queue_data_in,
2036         .queue_status                   = tcm_vhost_queue_status,
2037         .queue_tm_rsp                   = tcm_vhost_queue_tm_rsp,
2038         /*
2039          * Setup callers for generic logic in target_core_fabric_configfs.c
2040          */
2041         .fabric_make_wwn                = tcm_vhost_make_tport,
2042         .fabric_drop_wwn                = tcm_vhost_drop_tport,
2043         .fabric_make_tpg                = tcm_vhost_make_tpg,
2044         .fabric_drop_tpg                = tcm_vhost_drop_tpg,
2045         .fabric_post_link               = tcm_vhost_port_link,
2046         .fabric_pre_unlink              = tcm_vhost_port_unlink,
2047         .fabric_make_np                 = NULL,
2048         .fabric_drop_np                 = NULL,
2049         .fabric_make_nodeacl            = tcm_vhost_make_nodeacl,
2050         .fabric_drop_nodeacl            = tcm_vhost_drop_nodeacl,
2051 };
2052
2053 static int tcm_vhost_register_configfs(void)
2054 {
2055         struct target_fabric_configfs *fabric;
2056         int ret;
2057
2058         pr_debug("TCM_VHOST fabric module %s on %s/%s"
2059                 " on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname,
2060                 utsname()->machine);
2061         /*
2062          * Register the top level struct config_item_type with TCM core
2063          */
2064         fabric = target_fabric_configfs_init(THIS_MODULE, "vhost");
2065         if (IS_ERR(fabric)) {
2066                 pr_err("target_fabric_configfs_init() failed\n");
2067                 return PTR_ERR(fabric);
2068         }
2069         /*
2070          * Setup fabric->tf_ops from our local tcm_vhost_ops
2071          */
2072         fabric->tf_ops = tcm_vhost_ops;
2073         /*
2074          * Setup default attribute lists for various fabric->tf_cit_tmpl
2075          */
2076         TF_CIT_TMPL(fabric)->tfc_wwn_cit.ct_attrs = tcm_vhost_wwn_attrs;
2077         TF_CIT_TMPL(fabric)->tfc_tpg_base_cit.ct_attrs = tcm_vhost_tpg_attrs;
2078         TF_CIT_TMPL(fabric)->tfc_tpg_attrib_cit.ct_attrs = NULL;
2079         TF_CIT_TMPL(fabric)->tfc_tpg_param_cit.ct_attrs = NULL;
2080         TF_CIT_TMPL(fabric)->tfc_tpg_np_base_cit.ct_attrs = NULL;
2081         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_base_cit.ct_attrs = NULL;
2082         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_attrib_cit.ct_attrs = NULL;
2083         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_auth_cit.ct_attrs = NULL;
2084         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_param_cit.ct_attrs = NULL;
2085         /*
2086          * Register the fabric for use within TCM
2087          */
2088         ret = target_fabric_configfs_register(fabric);
2089         if (ret < 0) {
2090                 pr_err("target_fabric_configfs_register() failed"
2091                                 " for TCM_VHOST\n");
2092                 return ret;
2093         }
2094         /*
2095          * Setup our local pointer to *fabric
2096          */
2097         tcm_vhost_fabric_configfs = fabric;
2098         pr_debug("TCM_VHOST[0] - Set fabric -> tcm_vhost_fabric_configfs\n");
2099         return 0;
2100 };
2101
2102 static void tcm_vhost_deregister_configfs(void)
2103 {
2104         if (!tcm_vhost_fabric_configfs)
2105                 return;
2106
2107         target_fabric_configfs_deregister(tcm_vhost_fabric_configfs);
2108         tcm_vhost_fabric_configfs = NULL;
2109         pr_debug("TCM_VHOST[0] - Cleared tcm_vhost_fabric_configfs\n");
2110 };
2111
2112 static int __init tcm_vhost_init(void)
2113 {
2114         int ret = -ENOMEM;
2115         /*
2116          * Use our own dedicated workqueue for submitting I/O into
2117          * target core to avoid contention within system_wq.
2118          */
2119         tcm_vhost_workqueue = alloc_workqueue("tcm_vhost", 0, 0);
2120         if (!tcm_vhost_workqueue)
2121                 goto out;
2122
2123         ret = vhost_scsi_register();
2124         if (ret < 0)
2125                 goto out_destroy_workqueue;
2126
2127         ret = tcm_vhost_register_configfs();
2128         if (ret < 0)
2129                 goto out_vhost_scsi_deregister;
2130
2131         return 0;
2132
2133 out_vhost_scsi_deregister:
2134         vhost_scsi_deregister();
2135 out_destroy_workqueue:
2136         destroy_workqueue(tcm_vhost_workqueue);
2137 out:
2138         return ret;
2139 };
2140
2141 static void tcm_vhost_exit(void)
2142 {
2143         tcm_vhost_deregister_configfs();
2144         vhost_scsi_deregister();
2145         destroy_workqueue(tcm_vhost_workqueue);
2146 };
2147
2148 MODULE_DESCRIPTION("VHOST_SCSI series fabric driver");
2149 MODULE_ALIAS("tcm_vhost");
2150 MODULE_LICENSE("GPL");
2151 module_init(tcm_vhost_init);
2152 module_exit(tcm_vhost_exit);