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         /*
 900          * We can handle the vq only after the endpoint is setup by calling the
 901          * VHOST_SCSI_SET_ENDPOINT ioctl.
 902          *
 903          * TODO: Check that we are running from vhost_worker which acts
 904          * as read-side critical section for vhost kind of RCU.
 905          * See the comments in struct vhost_virtqueue in drivers/vhost/vhost.h
 906          */
 907         vs_tpg = rcu_dereference_check(vq->private_data, 1);
 908         if (!vs_tpg)
 909                 return;
 910
 911         mutex_lock(&vq->mutex);
 912         vhost_disable_notify(&vs->dev, vq);
 913
 914         for (;;) {
 915                 head = vhost_get_vq_desc(&vs->dev, vq, vq->iov,
 916                                         ARRAY_SIZE(vq->iov), &out, &in,
 917                                         NULL, NULL);
 918                 pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n",
 919                                         head, out, in);
 920                 /* On error, stop handling until the next kick. */
 921                 if (unlikely(head < 0))
 922                         break;
 923                 /* Nothing new?  Wait for eventfd to tell us they refilled. */
 924                 if (head == vq->num) {
 925                         if (unlikely(vhost_enable_notify(&vs->dev, vq))) {
 926                                 vhost_disable_notify(&vs->dev, vq);
 927                                 continue;
 928                         }
 929                         break;
 930                 }
 931
 932 /* FIXME: BIDI operation */
 933                 if (out == 1 && in == 1) {
 934                         data_direction = DMA_NONE;
 935                         data_first = 0;
 936                         data_num = 0;
 937                 } else if (out == 1 && in > 1) {
 938                         data_direction = DMA_FROM_DEVICE;
 939                         data_first = out + 1;
 940                         data_num = in - 1;
 941                 } else if (out > 1 && in == 1) {
 942                         data_direction = DMA_TO_DEVICE;
 943                         data_first = 1;
 944                         data_num = out - 1;
 945                 } else {
 946                         vq_err(vq, "Invalid buffer layout out: %u in: %u\n",
 947                                         out, in);
 948                         break;
 949                 }
 950
 951                 /*
 952                  * Check for a sane resp buffer so we can report errors to
 953                  * the guest.
 954                  */
 955                 if (unlikely(vq->iov[out].iov_len !=
 956                                         sizeof(struct virtio_scsi_cmd_resp))) {
 957                         vq_err(vq, "Expecting virtio_scsi_cmd_resp, got %zu"
 958                                 " bytes\n", vq->iov[out].iov_len);
 959                         break;
 960                 }
 961
 962                 if (unlikely(vq->iov[0].iov_len != sizeof(v_req))) {
 963                         vq_err(vq, "Expecting virtio_scsi_cmd_req, got %zu"
 964                                 " bytes\n", vq->iov[0].iov_len);
 965                         break;
 966                 }
 967                 pr_debug("Calling __copy_from_user: vq->iov[0].iov_base: %p,"
 968                         " len: %zu\n", vq->iov[0].iov_base, sizeof(v_req));
 969                 ret = __copy_from_user(&v_req, vq->iov[0].iov_base,
 970                                 sizeof(v_req));
 971                 if (unlikely(ret)) {
 972                         vq_err(vq, "Faulted on virtio_scsi_cmd_req\n");
 973                         break;
 974                 }
 975
 976                 /* Extract the tpgt */
 977                 target = v_req.lun[1];
 978                 tpg = ACCESS_ONCE(vs_tpg[target]);
 979
 980                 /* Target does not exist, fail the request */
 981                 if (unlikely(!tpg)) {
 982                         vhost_scsi_send_bad_target(vs, vq, head, out);
 983                         continue;
 984                 }
 985
 986                 exp_data_len = 0;
 987                 for (i = 0; i < data_num; i++)
 988                         exp_data_len += vq->iov[data_first + i].iov_len;
 989
 990                 cmd = vhost_scsi_allocate_cmd(vq, tpg, &v_req,
 991                                         exp_data_len, data_direction);
 992                 if (IS_ERR(cmd)) {
 993                         vq_err(vq, "vhost_scsi_allocate_cmd failed %ld\n",
 994                                         PTR_ERR(cmd));
 995                         goto err_cmd;
 996                 }
 997                 pr_debug("Allocated tv_cmd: %p exp_data_len: %d, data_direction"
 998                         ": %d\n", cmd, exp_data_len, data_direction);
 999
1000                 cmd->tvc_vhost = vs;
1001                 cmd->tvc_vq = vq;
1002                 cmd->tvc_resp = vq->iov[out].iov_base;
1003
1004                 /*
1005                  * Copy in the recieved CDB descriptor into cmd->tvc_cdb
1006                  * that will be used by tcm_vhost_new_cmd_map() and down into
1007                  * target_setup_cmd_from_cdb()
1008                  */
1009                 memcpy(cmd->tvc_cdb, v_req.cdb, TCM_VHOST_MAX_CDB_SIZE);
1010                 /*
1011                  * Check that the recieved CDB size does not exceeded our
1012                  * hardcoded max for tcm_vhost
1013                  */
1014                 /* TODO what if cdb was too small for varlen cdb header? */
1015                 if (unlikely(scsi_command_size(cmd->tvc_cdb) >
1016                                         TCM_VHOST_MAX_CDB_SIZE)) {
1017                         vq_err(vq, "Received SCSI CDB with command_size: %d that"
1018                                 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1019                                 scsi_command_size(cmd->tvc_cdb),
1020                                 TCM_VHOST_MAX_CDB_SIZE);
1021                         goto err_free;
1022                 }
1023                 cmd->tvc_lun = ((v_req.lun[2] << 8) | v_req.lun[3]) & 0x3FFF;
1024
1025                 pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n",
1026                         cmd->tvc_cdb[0], cmd->tvc_lun);
1027
1028                 if (data_direction != DMA_NONE) {
1029                         ret = vhost_scsi_map_iov_to_sgl(cmd,
1030                                         &vq->iov[data_first], data_num,
1031                                         data_direction == DMA_TO_DEVICE);
1032                         if (unlikely(ret)) {
1033                                 vq_err(vq, "Failed to map iov to sgl\n");
1034                                 goto err_free;
1035                         }
1036                 }
1037
1038                 /*
1039                  * Save the descriptor from vhost_get_vq_desc() to be used to
1040                  * complete the virtio-scsi request in TCM callback context via
1041                  * tcm_vhost_queue_data_in() and tcm_vhost_queue_status()
1042                  */
1043                 cmd->tvc_vq_desc = head;
1044                 /*
1045                  * Dispatch tv_cmd descriptor for cmwq execution in process
1046                  * context provided by tcm_vhost_workqueue.  This also ensures
1047                  * tv_cmd is executed on the same kworker CPU as this vhost
1048                  * thread to gain positive L2 cache locality effects..
1049                  */
1050                 INIT_WORK(&cmd->work, tcm_vhost_submission_work);
1051                 queue_work(tcm_vhost_workqueue, &cmd->work);
1052         }
1053
1054         mutex_unlock(&vq->mutex);
1055         return;
1056
1057 err_free:
1058         vhost_scsi_free_cmd(cmd);
1059 err_cmd:
1060         vhost_scsi_send_bad_target(vs, vq, head, out);
1061         mutex_unlock(&vq->mutex);
1062 }
1063
1064 static void vhost_scsi_ctl_handle_kick(struct vhost_work *work)
1065 {
1066         pr_debug("%s: The handling func for control queue.\n", __func__);
1067 }
1068
1069 static void
1070 tcm_vhost_send_evt(struct vhost_scsi *vs,
1071                    struct tcm_vhost_tpg *tpg,
1072                    struct se_lun *lun,
1073                    u32 event,
1074                    u32 reason)
1075 {
1076         struct tcm_vhost_evt *evt;
1077
1078         evt = tcm_vhost_allocate_evt(vs, event, reason);
1079         if (!evt)
1080                 return;
1081
1082         if (tpg && lun) {
1083                 /* TODO: share lun setup code with virtio-scsi.ko */
1084                 /*
1085                  * Note: evt->event is zeroed when we allocate it and
1086                  * lun[4-7] need to be zero according to virtio-scsi spec.
1087                  */
1088                 evt->event.lun[0] = 0x01;
1089                 evt->event.lun[1] = tpg->tport_tpgt & 0xFF;
1090                 if (lun->unpacked_lun >= 256)
1091                         evt->event.lun[2] = lun->unpacked_lun >> 8 | 0x40 ;
1092                 evt->event.lun[3] = lun->unpacked_lun & 0xFF;
1093         }
1094
1095         llist_add(&evt->list, &vs->vs_event_list);
1096         vhost_work_queue(&vs->dev, &vs->vs_event_work);
1097 }
1098
1099 static void vhost_scsi_evt_handle_kick(struct vhost_work *work)
1100 {
1101         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1102                                                 poll.work);
1103         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1104
1105         mutex_lock(&vq->mutex);
1106         if (!vq->private_data)
1107                 goto out;
1108
1109         if (vs->vs_events_missed)
1110                 tcm_vhost_send_evt(vs, NULL, NULL, VIRTIO_SCSI_T_NO_EVENT, 0);
1111 out:
1112         mutex_unlock(&vq->mutex);
1113 }
1114
1115 static void vhost_scsi_handle_kick(struct vhost_work *work)
1116 {
1117         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1118                                                 poll.work);
1119         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1120
1121         vhost_scsi_handle_vq(vs, vq);
1122 }
1123
1124 static void vhost_scsi_flush_vq(struct vhost_scsi *vs, int index)
1125 {
1126         vhost_poll_flush(&vs->vqs[index].vq.poll);
1127 }
1128
1129 /* Callers must hold dev mutex */
1130 static void vhost_scsi_flush(struct vhost_scsi *vs)
1131 {
1132         struct vhost_scsi_inflight *old_inflight[VHOST_SCSI_MAX_VQ];
1133         int i;
1134
1135         /* Init new inflight and remember the old inflight */
1136         tcm_vhost_init_inflight(vs, old_inflight);
1137
1138         /*
1139          * The inflight->kref was initialized to 1. We decrement it here to
1140          * indicate the start of the flush operation so that it will reach 0
1141          * when all the reqs are finished.
1142          */
1143         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1144                 kref_put(&old_inflight[i]->kref, tcm_vhost_done_inflight);
1145
1146         /* Flush both the vhost poll and vhost work */
1147         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1148                 vhost_scsi_flush_vq(vs, i);
1149         vhost_work_flush(&vs->dev, &vs->vs_completion_work);
1150         vhost_work_flush(&vs->dev, &vs->vs_event_work);
1151
1152         /* Wait for all reqs issued before the flush to be finished */
1153         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1154                 wait_for_completion(&old_inflight[i]->comp);
1155 }
1156
1157 /*
1158  * Called from vhost_scsi_ioctl() context to walk the list of available
1159  * tcm_vhost_tpg with an active struct tcm_vhost_nexus
1160  *
1161  *  The lock nesting rule is:
1162  *    tcm_vhost_mutex -> vs->dev.mutex -> tpg->tv_tpg_mutex -> vq->mutex
1163  */
1164 static int
1165 vhost_scsi_set_endpoint(struct vhost_scsi *vs,
1166                         struct vhost_scsi_target *t)
1167 {
1168         struct tcm_vhost_tport *tv_tport;
1169         struct tcm_vhost_tpg *tpg;
1170         struct tcm_vhost_tpg **vs_tpg;
1171         struct vhost_virtqueue *vq;
1172         int index, ret, i, len;
1173         bool match = false;
1174
1175         mutex_lock(&tcm_vhost_mutex);
1176         mutex_lock(&vs->dev.mutex);
1177
1178         /* Verify that ring has been setup correctly. */
1179         for (index = 0; index < vs->dev.nvqs; ++index) {
1180                 /* Verify that ring has been setup correctly. */
1181                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1182                         ret = -EFAULT;
1183                         goto out;
1184                 }
1185         }
1186
1187         len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET;
1188         vs_tpg = kzalloc(len, GFP_KERNEL);
1189         if (!vs_tpg) {
1190                 ret = -ENOMEM;
1191                 goto out;
1192         }
1193         if (vs->vs_tpg)
1194                 memcpy(vs_tpg, vs->vs_tpg, len);
1195
1196         list_for_each_entry(tpg, &tcm_vhost_list, tv_tpg_list) {
1197                 mutex_lock(&tpg->tv_tpg_mutex);
1198                 if (!tpg->tpg_nexus) {
1199                         mutex_unlock(&tpg->tv_tpg_mutex);
1200                         continue;
1201                 }
1202                 if (tpg->tv_tpg_vhost_count != 0) {
1203                         mutex_unlock(&tpg->tv_tpg_mutex);
1204                         continue;
1205                 }
1206                 tv_tport = tpg->tport;
1207
1208                 if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1209                         if (vs->vs_tpg && vs->vs_tpg[tpg->tport_tpgt]) {
1210                                 kfree(vs_tpg);
1211                                 mutex_unlock(&tpg->tv_tpg_mutex);
1212                                 ret = -EEXIST;
1213                                 goto out;
1214                         }
1215                         tpg->tv_tpg_vhost_count++;
1216                         tpg->vhost_scsi = vs;
1217                         vs_tpg[tpg->tport_tpgt] = tpg;
1218                         smp_mb__after_atomic_inc();
1219                         match = true;
1220                 }
1221                 mutex_unlock(&tpg->tv_tpg_mutex);
1222         }
1223
1224         if (match) {
1225                 memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
1226                        sizeof(vs->vs_vhost_wwpn));
1227                 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1228                         vq = &vs->vqs[i].vq;
1229                         /* Flushing the vhost_work acts as synchronize_rcu */
1230                         mutex_lock(&vq->mutex);
1231                         rcu_assign_pointer(vq->private_data, vs_tpg);
1232                         vhost_init_used(vq);
1233                         mutex_unlock(&vq->mutex);
1234                 }
1235                 ret = 0;
1236         } else {
1237                 ret = -EEXIST;
1238         }
1239
1240         /*
1241          * Act as synchronize_rcu to make sure access to
1242          * old vs->vs_tpg is finished.
1243          */
1244         vhost_scsi_flush(vs);
1245         kfree(vs->vs_tpg);
1246         vs->vs_tpg = vs_tpg;
1247
1248 out:
1249         mutex_unlock(&vs->dev.mutex);
1250         mutex_unlock(&tcm_vhost_mutex);
1251         return ret;
1252 }
1253
1254 static int
1255 vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
1256                           struct vhost_scsi_target *t)
1257 {
1258         struct tcm_vhost_tport *tv_tport;
1259         struct tcm_vhost_tpg *tpg;
1260         struct vhost_virtqueue *vq;
1261         bool match = false;
1262         int index, ret, i;
1263         u8 target;
1264
1265         mutex_lock(&tcm_vhost_mutex);
1266         mutex_lock(&vs->dev.mutex);
1267         /* Verify that ring has been setup correctly. */
1268         for (index = 0; index < vs->dev.nvqs; ++index) {
1269                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1270                         ret = -EFAULT;
1271                         goto err_dev;
1272                 }
1273         }
1274
1275         if (!vs->vs_tpg) {
1276                 ret = 0;
1277                 goto err_dev;
1278         }
1279
1280         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1281                 target = i;
1282                 tpg = vs->vs_tpg[target];
1283                 if (!tpg)
1284                         continue;
1285
1286                 mutex_lock(&tpg->tv_tpg_mutex);
1287                 tv_tport = tpg->tport;
1288                 if (!tv_tport) {
1289                         ret = -ENODEV;
1290                         goto err_tpg;
1291                 }
1292
1293                 if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1294                         pr_warn("tv_tport->tport_name: %s, tpg->tport_tpgt: %hu"
1295                                 " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
1296                                 tv_tport->tport_name, tpg->tport_tpgt,
1297                                 t->vhost_wwpn, t->vhost_tpgt);
1298                         ret = -EINVAL;
1299                         goto err_tpg;
1300                 }
1301                 tpg->tv_tpg_vhost_count--;
1302                 tpg->vhost_scsi = NULL;
1303                 vs->vs_tpg[target] = NULL;
1304                 match = true;
1305                 mutex_unlock(&tpg->tv_tpg_mutex);
1306         }
1307         if (match) {
1308                 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1309                         vq = &vs->vqs[i].vq;
1310                         /* Flushing the vhost_work acts as synchronize_rcu */
1311                         mutex_lock(&vq->mutex);
1312                         rcu_assign_pointer(vq->private_data, NULL);
1313                         mutex_unlock(&vq->mutex);
1314                 }
1315         }
1316         /*
1317          * Act as synchronize_rcu to make sure access to
1318          * old vs->vs_tpg is finished.
1319          */
1320         vhost_scsi_flush(vs);
1321         kfree(vs->vs_tpg);
1322         vs->vs_tpg = NULL;
1323         WARN_ON(vs->vs_events_nr);
1324         mutex_unlock(&vs->dev.mutex);
1325         mutex_unlock(&tcm_vhost_mutex);
1326         return 0;
1327
1328 err_tpg:
1329         mutex_unlock(&tpg->tv_tpg_mutex);
1330 err_dev:
1331         mutex_unlock(&vs->dev.mutex);
1332         mutex_unlock(&tcm_vhost_mutex);
1333         return ret;
1334 }
1335
1336 static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features)
1337 {
1338         if (features & ~VHOST_SCSI_FEATURES)
1339                 return -EOPNOTSUPP;
1340
1341         mutex_lock(&vs->dev.mutex);
1342         if ((features & (1 << VHOST_F_LOG_ALL)) &&
1343             !vhost_log_access_ok(&vs->dev)) {
1344                 mutex_unlock(&vs->dev.mutex);
1345                 return -EFAULT;
1346         }
1347         vs->dev.acked_features = features;
1348         smp_wmb();
1349         vhost_scsi_flush(vs);
1350         mutex_unlock(&vs->dev.mutex);
1351         return 0;
1352 }
1353
1354 static int vhost_scsi_open(struct inode *inode, struct file *f)
1355 {
1356         struct vhost_scsi *vs;
1357         struct vhost_virtqueue **vqs;
1358         int r, i;
1359
1360         vs = kzalloc(sizeof(*vs), GFP_KERNEL);
1361         if (!vs)
1362                 return -ENOMEM;
1363
1364         vqs = kmalloc(VHOST_SCSI_MAX_VQ * sizeof(*vqs), GFP_KERNEL);
1365         if (!vqs) {
1366                 kfree(vs);
1367                 return -ENOMEM;
1368         }
1369
1370         vhost_work_init(&vs->vs_completion_work, vhost_scsi_complete_cmd_work);
1371         vhost_work_init(&vs->vs_event_work, tcm_vhost_evt_work);
1372
1373         vs->vs_events_nr = 0;
1374         vs->vs_events_missed = false;
1375
1376         vqs[VHOST_SCSI_VQ_CTL] = &vs->vqs[VHOST_SCSI_VQ_CTL].vq;
1377         vqs[VHOST_SCSI_VQ_EVT] = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1378         vs->vqs[VHOST_SCSI_VQ_CTL].vq.handle_kick = vhost_scsi_ctl_handle_kick;
1379         vs->vqs[VHOST_SCSI_VQ_EVT].vq.handle_kick = vhost_scsi_evt_handle_kick;
1380         for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++) {
1381                 vqs[i] = &vs->vqs[i].vq;
1382                 vs->vqs[i].vq.handle_kick = vhost_scsi_handle_kick;
1383         }
1384         r = vhost_dev_init(&vs->dev, vqs, VHOST_SCSI_MAX_VQ);
1385
1386         tcm_vhost_init_inflight(vs, NULL);
1387
1388         if (r < 0) {
1389                 kfree(vqs);
1390                 kfree(vs);
1391                 return r;
1392         }
1393
1394         f->private_data = vs;
1395         return 0;
1396 }
1397
1398 static int vhost_scsi_release(struct inode *inode, struct file *f)
1399 {
1400         struct vhost_scsi *vs = f->private_data;
1401         struct vhost_scsi_target t;
1402
1403         mutex_lock(&vs->dev.mutex);
1404         memcpy(t.vhost_wwpn, vs->vs_vhost_wwpn, sizeof(t.vhost_wwpn));
1405         mutex_unlock(&vs->dev.mutex);
1406         vhost_scsi_clear_endpoint(vs, &t);
1407         vhost_dev_stop(&vs->dev);
1408         vhost_dev_cleanup(&vs->dev, false);
1409         /* Jobs can re-queue themselves in evt kick handler. Do extra flush. */
1410         vhost_scsi_flush(vs);
1411         kfree(vs->dev.vqs);
1412         kfree(vs);
1413         return 0;
1414 }
1415
1416 static long
1417 vhost_scsi_ioctl(struct file *f,
1418                  unsigned int ioctl,
1419                  unsigned long arg)
1420 {
1421         struct vhost_scsi *vs = f->private_data;
1422         struct vhost_scsi_target backend;
1423         void __user *argp = (void __user *)arg;
1424         u64 __user *featurep = argp;
1425         u32 __user *eventsp = argp;
1426         u32 events_missed;
1427         u64 features;
1428         int r, abi_version = VHOST_SCSI_ABI_VERSION;
1429         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1430
1431         switch (ioctl) {
1432         case VHOST_SCSI_SET_ENDPOINT:
1433                 if (copy_from_user(&backend, argp, sizeof backend))
1434                         return -EFAULT;
1435                 if (backend.reserved != 0)
1436                         return -EOPNOTSUPP;
1437
1438                 return vhost_scsi_set_endpoint(vs, &backend);
1439         case VHOST_SCSI_CLEAR_ENDPOINT:
1440                 if (copy_from_user(&backend, argp, sizeof backend))
1441                         return -EFAULT;
1442                 if (backend.reserved != 0)
1443                         return -EOPNOTSUPP;
1444
1445                 return vhost_scsi_clear_endpoint(vs, &backend);
1446         case VHOST_SCSI_GET_ABI_VERSION:
1447                 if (copy_to_user(argp, &abi_version, sizeof abi_version))
1448                         return -EFAULT;
1449                 return 0;
1450         case VHOST_SCSI_SET_EVENTS_MISSED:
1451                 if (get_user(events_missed, eventsp))
1452                         return -EFAULT;
1453                 mutex_lock(&vq->mutex);
1454                 vs->vs_events_missed = events_missed;
1455                 mutex_unlock(&vq->mutex);
1456                 return 0;
1457         case VHOST_SCSI_GET_EVENTS_MISSED:
1458                 mutex_lock(&vq->mutex);
1459                 events_missed = vs->vs_events_missed;
1460                 mutex_unlock(&vq->mutex);
1461                 if (put_user(events_missed, eventsp))
1462                         return -EFAULT;
1463                 return 0;
1464         case VHOST_GET_FEATURES:
1465                 features = VHOST_SCSI_FEATURES;
1466                 if (copy_to_user(featurep, &features, sizeof features))
1467                         return -EFAULT;
1468                 return 0;
1469         case VHOST_SET_FEATURES:
1470                 if (copy_from_user(&features, featurep, sizeof features))
1471                         return -EFAULT;
1472                 return vhost_scsi_set_features(vs, features);
1473         default:
1474                 mutex_lock(&vs->dev.mutex);
1475                 r = vhost_dev_ioctl(&vs->dev, ioctl, argp);
1476                 /* TODO: flush backend after dev ioctl. */
1477                 if (r == -ENOIOCTLCMD)
1478                         r = vhost_vring_ioctl(&vs->dev, ioctl, argp);
1479                 mutex_unlock(&vs->dev.mutex);
1480                 return r;
1481         }
1482 }
1483
1484 #ifdef CONFIG_COMPAT
1485 static long vhost_scsi_compat_ioctl(struct file *f, unsigned int ioctl,
1486                                 unsigned long arg)
1487 {
1488         return vhost_scsi_ioctl(f, ioctl, (unsigned long)compat_ptr(arg));
1489 }
1490 #endif
1491
1492 static const struct file_operations vhost_scsi_fops = {
1493         .owner          = THIS_MODULE,
1494         .release        = vhost_scsi_release,
1495         .unlocked_ioctl = vhost_scsi_ioctl,
1496 #ifdef CONFIG_COMPAT
1497         .compat_ioctl   = vhost_scsi_compat_ioctl,
1498 #endif
1499         .open           = vhost_scsi_open,
1500         .llseek         = noop_llseek,
1501 };
1502
1503 static struct miscdevice vhost_scsi_misc = {
1504         MISC_DYNAMIC_MINOR,
1505         "vhost-scsi",
1506         &vhost_scsi_fops,
1507 };
1508
1509 static int __init vhost_scsi_register(void)
1510 {
1511         return misc_register(&vhost_scsi_misc);
1512 }
1513
1514 static int vhost_scsi_deregister(void)
1515 {
1516         return misc_deregister(&vhost_scsi_misc);
1517 }
1518
1519 static char *tcm_vhost_dump_proto_id(struct tcm_vhost_tport *tport)
1520 {
1521         switch (tport->tport_proto_id) {
1522         case SCSI_PROTOCOL_SAS:
1523                 return "SAS";
1524         case SCSI_PROTOCOL_FCP:
1525                 return "FCP";
1526         case SCSI_PROTOCOL_ISCSI:
1527                 return "iSCSI";
1528         default:
1529                 break;
1530         }
1531
1532         return "Unknown";
1533 }
1534
1535 static void
1536 tcm_vhost_do_plug(struct tcm_vhost_tpg *tpg,
1537                   struct se_lun *lun, bool plug)
1538 {
1539
1540         struct vhost_scsi *vs = tpg->vhost_scsi;
1541         struct vhost_virtqueue *vq;
1542         u32 reason;
1543
1544         if (!vs)
1545                 return;
1546
1547         mutex_lock(&vs->dev.mutex);
1548         if (!vhost_has_feature(&vs->dev, VIRTIO_SCSI_F_HOTPLUG)) {
1549                 mutex_unlock(&vs->dev.mutex);
1550                 return;
1551         }
1552
1553         if (plug)
1554                 reason = VIRTIO_SCSI_EVT_RESET_RESCAN;
1555         else
1556                 reason = VIRTIO_SCSI_EVT_RESET_REMOVED;
1557
1558         vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1559         mutex_lock(&vq->mutex);
1560         tcm_vhost_send_evt(vs, tpg, lun,
1561                         VIRTIO_SCSI_T_TRANSPORT_RESET, reason);
1562         mutex_unlock(&vq->mutex);
1563         mutex_unlock(&vs->dev.mutex);
1564 }
1565
1566 static void tcm_vhost_hotplug(struct tcm_vhost_tpg *tpg, struct se_lun *lun)
1567 {
1568         tcm_vhost_do_plug(tpg, lun, true);
1569 }
1570
1571 static void tcm_vhost_hotunplug(struct tcm_vhost_tpg *tpg, struct se_lun *lun)
1572 {
1573         tcm_vhost_do_plug(tpg, lun, false);
1574 }
1575
1576 static int tcm_vhost_port_link(struct se_portal_group *se_tpg,
1577                                struct se_lun *lun)
1578 {
1579         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1580                                 struct tcm_vhost_tpg, se_tpg);
1581
1582         mutex_lock(&tcm_vhost_mutex);
1583
1584         mutex_lock(&tpg->tv_tpg_mutex);
1585         tpg->tv_tpg_port_count++;
1586         mutex_unlock(&tpg->tv_tpg_mutex);
1587
1588         tcm_vhost_hotplug(tpg, lun);
1589
1590         mutex_unlock(&tcm_vhost_mutex);
1591
1592         return 0;
1593 }
1594
1595 static void tcm_vhost_port_unlink(struct se_portal_group *se_tpg,
1596                                   struct se_lun *lun)
1597 {
1598         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1599                                 struct tcm_vhost_tpg, se_tpg);
1600
1601         mutex_lock(&tcm_vhost_mutex);
1602
1603         mutex_lock(&tpg->tv_tpg_mutex);
1604         tpg->tv_tpg_port_count--;
1605         mutex_unlock(&tpg->tv_tpg_mutex);
1606
1607         tcm_vhost_hotunplug(tpg, lun);
1608
1609         mutex_unlock(&tcm_vhost_mutex);
1610 }
1611
1612 static struct se_node_acl *
1613 tcm_vhost_make_nodeacl(struct se_portal_group *se_tpg,
1614                        struct config_group *group,
1615                        const char *name)
1616 {
1617         struct se_node_acl *se_nacl, *se_nacl_new;
1618         struct tcm_vhost_nacl *nacl;
1619         u64 wwpn = 0;
1620         u32 nexus_depth;
1621
1622         /* tcm_vhost_parse_wwn(name, &wwpn, 1) < 0)
1623                 return ERR_PTR(-EINVAL); */
1624         se_nacl_new = tcm_vhost_alloc_fabric_acl(se_tpg);
1625         if (!se_nacl_new)
1626                 return ERR_PTR(-ENOMEM);
1627
1628         nexus_depth = 1;
1629         /*
1630          * se_nacl_new may be released by core_tpg_add_initiator_node_acl()
1631          * when converting a NodeACL from demo mode -> explict
1632          */
1633         se_nacl = core_tpg_add_initiator_node_acl(se_tpg, se_nacl_new,
1634                                 name, nexus_depth);
1635         if (IS_ERR(se_nacl)) {
1636                 tcm_vhost_release_fabric_acl(se_tpg, se_nacl_new);
1637                 return se_nacl;
1638         }
1639         /*
1640          * Locate our struct tcm_vhost_nacl and set the FC Nport WWPN
1641          */
1642         nacl = container_of(se_nacl, struct tcm_vhost_nacl, se_node_acl);
1643         nacl->iport_wwpn = wwpn;
1644
1645         return se_nacl;
1646 }
1647
1648 static void tcm_vhost_drop_nodeacl(struct se_node_acl *se_acl)
1649 {
1650         struct tcm_vhost_nacl *nacl = container_of(se_acl,
1651                                 struct tcm_vhost_nacl, se_node_acl);
1652         core_tpg_del_initiator_node_acl(se_acl->se_tpg, se_acl, 1);
1653         kfree(nacl);
1654 }
1655
1656 static int tcm_vhost_make_nexus(struct tcm_vhost_tpg *tpg,
1657                                 const char *name)
1658 {
1659         struct se_portal_group *se_tpg;
1660         struct tcm_vhost_nexus *tv_nexus;
1661
1662         mutex_lock(&tpg->tv_tpg_mutex);
1663         if (tpg->tpg_nexus) {
1664                 mutex_unlock(&tpg->tv_tpg_mutex);
1665                 pr_debug("tpg->tpg_nexus already exists\n");
1666                 return -EEXIST;
1667         }
1668         se_tpg = &tpg->se_tpg;
1669
1670         tv_nexus = kzalloc(sizeof(struct tcm_vhost_nexus), GFP_KERNEL);
1671         if (!tv_nexus) {
1672                 mutex_unlock(&tpg->tv_tpg_mutex);
1673                 pr_err("Unable to allocate struct tcm_vhost_nexus\n");
1674                 return -ENOMEM;
1675         }
1676         /*
1677          *  Initialize the struct se_session pointer
1678          */
1679         tv_nexus->tvn_se_sess = transport_init_session();
1680         if (IS_ERR(tv_nexus->tvn_se_sess)) {
1681                 mutex_unlock(&tpg->tv_tpg_mutex);
1682                 kfree(tv_nexus);
1683                 return -ENOMEM;
1684         }
1685         /*
1686          * Since we are running in 'demo mode' this call with generate a
1687          * struct se_node_acl for the tcm_vhost struct se_portal_group with
1688          * the SCSI Initiator port name of the passed configfs group 'name'.
1689          */
1690         tv_nexus->tvn_se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
1691                                 se_tpg, (unsigned char *)name);
1692         if (!tv_nexus->tvn_se_sess->se_node_acl) {
1693                 mutex_unlock(&tpg->tv_tpg_mutex);
1694                 pr_debug("core_tpg_check_initiator_node_acl() failed"
1695                                 " for %s\n", name);
1696                 transport_free_session(tv_nexus->tvn_se_sess);
1697                 kfree(tv_nexus);
1698                 return -ENOMEM;
1699         }
1700         /*
1701          * Now register the TCM vhost virtual I_T Nexus as active with the
1702          * call to __transport_register_session()
1703          */
1704         __transport_register_session(se_tpg, tv_nexus->tvn_se_sess->se_node_acl,
1705                         tv_nexus->tvn_se_sess, tv_nexus);
1706         tpg->tpg_nexus = tv_nexus;
1707
1708         mutex_unlock(&tpg->tv_tpg_mutex);
1709         return 0;
1710 }
1711
1712 static int tcm_vhost_drop_nexus(struct tcm_vhost_tpg *tpg)
1713 {
1714         struct se_session *se_sess;
1715         struct tcm_vhost_nexus *tv_nexus;
1716
1717         mutex_lock(&tpg->tv_tpg_mutex);
1718         tv_nexus = tpg->tpg_nexus;
1719         if (!tv_nexus) {
1720                 mutex_unlock(&tpg->tv_tpg_mutex);
1721                 return -ENODEV;
1722         }
1723
1724         se_sess = tv_nexus->tvn_se_sess;
1725         if (!se_sess) {
1726                 mutex_unlock(&tpg->tv_tpg_mutex);
1727                 return -ENODEV;
1728         }
1729
1730         if (tpg->tv_tpg_port_count != 0) {
1731                 mutex_unlock(&tpg->tv_tpg_mutex);
1732                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
1733                         " active TPG port count: %d\n",
1734                         tpg->tv_tpg_port_count);
1735                 return -EBUSY;
1736         }
1737
1738         if (tpg->tv_tpg_vhost_count != 0) {
1739                 mutex_unlock(&tpg->tv_tpg_mutex);
1740                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
1741                         " active TPG vhost count: %d\n",
1742                         tpg->tv_tpg_vhost_count);
1743                 return -EBUSY;
1744         }
1745
1746         pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated"
1747                 " %s Initiator Port: %s\n", tcm_vhost_dump_proto_id(tpg->tport),
1748                 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1749         /*
1750          * Release the SCSI I_T Nexus to the emulated vhost Target Port
1751          */
1752         transport_deregister_session(tv_nexus->tvn_se_sess);
1753         tpg->tpg_nexus = NULL;
1754         mutex_unlock(&tpg->tv_tpg_mutex);
1755
1756         kfree(tv_nexus);
1757         return 0;
1758 }
1759
1760 static ssize_t tcm_vhost_tpg_show_nexus(struct se_portal_group *se_tpg,
1761                                         char *page)
1762 {
1763         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1764                                 struct tcm_vhost_tpg, se_tpg);
1765         struct tcm_vhost_nexus *tv_nexus;
1766         ssize_t ret;
1767
1768         mutex_lock(&tpg->tv_tpg_mutex);
1769         tv_nexus = tpg->tpg_nexus;
1770         if (!tv_nexus) {
1771                 mutex_unlock(&tpg->tv_tpg_mutex);
1772                 return -ENODEV;
1773         }
1774         ret = snprintf(page, PAGE_SIZE, "%s\n",
1775                         tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1776         mutex_unlock(&tpg->tv_tpg_mutex);
1777
1778         return ret;
1779 }
1780
1781 static ssize_t tcm_vhost_tpg_store_nexus(struct se_portal_group *se_tpg,
1782                                          const char *page,
1783                                          size_t count)
1784 {
1785         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1786                                 struct tcm_vhost_tpg, se_tpg);
1787         struct tcm_vhost_tport *tport_wwn = tpg->tport;
1788         unsigned char i_port[TCM_VHOST_NAMELEN], *ptr, *port_ptr;
1789         int ret;
1790         /*
1791          * Shutdown the active I_T nexus if 'NULL' is passed..
1792          */
1793         if (!strncmp(page, "NULL", 4)) {
1794                 ret = tcm_vhost_drop_nexus(tpg);
1795                 return (!ret) ? count : ret;
1796         }
1797         /*
1798          * Otherwise make sure the passed virtual Initiator port WWN matches
1799          * the fabric protocol_id set in tcm_vhost_make_tport(), and call
1800          * tcm_vhost_make_nexus().
1801          */
1802         if (strlen(page) >= TCM_VHOST_NAMELEN) {
1803                 pr_err("Emulated NAA Sas Address: %s, exceeds"
1804                                 " max: %d\n", page, TCM_VHOST_NAMELEN);
1805                 return -EINVAL;
1806         }
1807         snprintf(&i_port[0], TCM_VHOST_NAMELEN, "%s", page);
1808
1809         ptr = strstr(i_port, "naa.");
1810         if (ptr) {
1811                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
1812                         pr_err("Passed SAS Initiator Port %s does not"
1813                                 " match target port protoid: %s\n", i_port,
1814                                 tcm_vhost_dump_proto_id(tport_wwn));
1815                         return -EINVAL;
1816                 }
1817                 port_ptr = &i_port[0];
1818                 goto check_newline;
1819         }
1820         ptr = strstr(i_port, "fc.");
1821         if (ptr) {
1822                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
1823                         pr_err("Passed FCP Initiator Port %s does not"
1824                                 " match target port protoid: %s\n", i_port,
1825                                 tcm_vhost_dump_proto_id(tport_wwn));
1826                         return -EINVAL;
1827                 }
1828                 port_ptr = &i_port[3]; /* Skip over "fc." */
1829                 goto check_newline;
1830         }
1831         ptr = strstr(i_port, "iqn.");
1832         if (ptr) {
1833                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
1834                         pr_err("Passed iSCSI Initiator Port %s does not"
1835                                 " match target port protoid: %s\n", i_port,
1836                                 tcm_vhost_dump_proto_id(tport_wwn));
1837                         return -EINVAL;
1838                 }
1839                 port_ptr = &i_port[0];
1840                 goto check_newline;
1841         }
1842         pr_err("Unable to locate prefix for emulated Initiator Port:"
1843                         " %s\n", i_port);
1844         return -EINVAL;
1845         /*
1846          * Clear any trailing newline for the NAA WWN
1847          */
1848 check_newline:
1849         if (i_port[strlen(i_port)-1] == '\n')
1850                 i_port[strlen(i_port)-1] = '\0';
1851
1852         ret = tcm_vhost_make_nexus(tpg, port_ptr);
1853         if (ret < 0)
1854                 return ret;
1855
1856         return count;
1857 }
1858
1859 TF_TPG_BASE_ATTR(tcm_vhost, nexus, S_IRUGO | S_IWUSR);
1860
1861 static struct configfs_attribute *tcm_vhost_tpg_attrs[] = {
1862         &tcm_vhost_tpg_nexus.attr,
1863         NULL,
1864 };
1865
1866 static struct se_portal_group *
1867 tcm_vhost_make_tpg(struct se_wwn *wwn,
1868                    struct config_group *group,
1869                    const char *name)
1870 {
1871         struct tcm_vhost_tport *tport = container_of(wwn,
1872                         struct tcm_vhost_tport, tport_wwn);
1873
1874         struct tcm_vhost_tpg *tpg;
1875         unsigned long tpgt;
1876         int ret;
1877
1878         if (strstr(name, "tpgt_") != name)
1879                 return ERR_PTR(-EINVAL);
1880         if (kstrtoul(name + 5, 10, &tpgt) || tpgt > UINT_MAX)
1881                 return ERR_PTR(-EINVAL);
1882
1883         tpg = kzalloc(sizeof(struct tcm_vhost_tpg), GFP_KERNEL);
1884         if (!tpg) {
1885                 pr_err("Unable to allocate struct tcm_vhost_tpg");
1886                 return ERR_PTR(-ENOMEM);
1887         }
1888         mutex_init(&tpg->tv_tpg_mutex);
1889         INIT_LIST_HEAD(&tpg->tv_tpg_list);
1890         tpg->tport = tport;
1891         tpg->tport_tpgt = tpgt;
1892
1893         ret = core_tpg_register(&tcm_vhost_fabric_configfs->tf_ops, wwn,
1894                                 &tpg->se_tpg, tpg, TRANSPORT_TPG_TYPE_NORMAL);
1895         if (ret < 0) {
1896                 kfree(tpg);
1897                 return NULL;
1898         }
1899         mutex_lock(&tcm_vhost_mutex);
1900         list_add_tail(&tpg->tv_tpg_list, &tcm_vhost_list);
1901         mutex_unlock(&tcm_vhost_mutex);
1902
1903         return &tpg->se_tpg;
1904 }
1905
1906 static void tcm_vhost_drop_tpg(struct se_portal_group *se_tpg)
1907 {
1908         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1909                                 struct tcm_vhost_tpg, se_tpg);
1910
1911         mutex_lock(&tcm_vhost_mutex);
1912         list_del(&tpg->tv_tpg_list);
1913         mutex_unlock(&tcm_vhost_mutex);
1914         /*
1915          * Release the virtual I_T Nexus for this vhost TPG
1916          */
1917         tcm_vhost_drop_nexus(tpg);
1918         /*
1919          * Deregister the se_tpg from TCM..
1920          */
1921         core_tpg_deregister(se_tpg);
1922         kfree(tpg);
1923 }
1924
1925 static struct se_wwn *
1926 tcm_vhost_make_tport(struct target_fabric_configfs *tf,
1927                      struct config_group *group,
1928                      const char *name)
1929 {
1930         struct tcm_vhost_tport *tport;
1931         char *ptr;
1932         u64 wwpn = 0;
1933         int off = 0;
1934
1935         /* if (tcm_vhost_parse_wwn(name, &wwpn, 1) < 0)
1936                 return ERR_PTR(-EINVAL); */
1937
1938         tport = kzalloc(sizeof(struct tcm_vhost_tport), GFP_KERNEL);
1939         if (!tport) {
1940                 pr_err("Unable to allocate struct tcm_vhost_tport");
1941                 return ERR_PTR(-ENOMEM);
1942         }
1943         tport->tport_wwpn = wwpn;
1944         /*
1945          * Determine the emulated Protocol Identifier and Target Port Name
1946          * based on the incoming configfs directory name.
1947          */
1948         ptr = strstr(name, "naa.");
1949         if (ptr) {
1950                 tport->tport_proto_id = SCSI_PROTOCOL_SAS;
1951                 goto check_len;
1952         }
1953         ptr = strstr(name, "fc.");
1954         if (ptr) {
1955                 tport->tport_proto_id = SCSI_PROTOCOL_FCP;
1956                 off = 3; /* Skip over "fc." */
1957                 goto check_len;
1958         }
1959         ptr = strstr(name, "iqn.");
1960         if (ptr) {
1961                 tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
1962                 goto check_len;
1963         }
1964
1965         pr_err("Unable to locate prefix for emulated Target Port:"
1966                         " %s\n", name);
1967         kfree(tport);
1968         return ERR_PTR(-EINVAL);
1969
1970 check_len:
1971         if (strlen(name) >= TCM_VHOST_NAMELEN) {
1972                 pr_err("Emulated %s Address: %s, exceeds"
1973                         " max: %d\n", name, tcm_vhost_dump_proto_id(tport),
1974                         TCM_VHOST_NAMELEN);
1975                 kfree(tport);
1976                 return ERR_PTR(-EINVAL);
1977         }
1978         snprintf(&tport->tport_name[0], TCM_VHOST_NAMELEN, "%s", &name[off]);
1979
1980         pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target"
1981                 " %s Address: %s\n", tcm_vhost_dump_proto_id(tport), name);
1982
1983         return &tport->tport_wwn;
1984 }
1985
1986 static void tcm_vhost_drop_tport(struct se_wwn *wwn)
1987 {
1988         struct tcm_vhost_tport *tport = container_of(wwn,
1989                                 struct tcm_vhost_tport, tport_wwn);
1990
1991         pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target"
1992                 " %s Address: %s\n", tcm_vhost_dump_proto_id(tport),
1993                 tport->tport_name);
1994
1995         kfree(tport);
1996 }
1997
1998 static ssize_t
1999 tcm_vhost_wwn_show_attr_version(struct target_fabric_configfs *tf,
2000                                 char *page)
2001 {
2002         return sprintf(page, "TCM_VHOST fabric module %s on %s/%s"
2003                 "on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname,
2004                 utsname()->machine);
2005 }
2006
2007 TF_WWN_ATTR_RO(tcm_vhost, version);
2008
2009 static struct configfs_attribute *tcm_vhost_wwn_attrs[] = {
2010         &tcm_vhost_wwn_version.attr,
2011         NULL,
2012 };
2013
2014 static struct target_core_fabric_ops tcm_vhost_ops = {
2015         .get_fabric_name                = tcm_vhost_get_fabric_name,
2016         .get_fabric_proto_ident         = tcm_vhost_get_fabric_proto_ident,
2017         .tpg_get_wwn                    = tcm_vhost_get_fabric_wwn,
2018         .tpg_get_tag                    = tcm_vhost_get_tag,
2019         .tpg_get_default_depth          = tcm_vhost_get_default_depth,
2020         .tpg_get_pr_transport_id        = tcm_vhost_get_pr_transport_id,
2021         .tpg_get_pr_transport_id_len    = tcm_vhost_get_pr_transport_id_len,
2022         .tpg_parse_pr_out_transport_id  = tcm_vhost_parse_pr_out_transport_id,
2023         .tpg_check_demo_mode            = tcm_vhost_check_true,
2024         .tpg_check_demo_mode_cache      = tcm_vhost_check_true,
2025         .tpg_check_demo_mode_write_protect = tcm_vhost_check_false,
2026         .tpg_check_prod_mode_write_protect = tcm_vhost_check_false,
2027         .tpg_alloc_fabric_acl           = tcm_vhost_alloc_fabric_acl,
2028         .tpg_release_fabric_acl         = tcm_vhost_release_fabric_acl,
2029         .tpg_get_inst_index             = tcm_vhost_tpg_get_inst_index,
2030         .release_cmd                    = tcm_vhost_release_cmd,
2031         .shutdown_session               = tcm_vhost_shutdown_session,
2032         .close_session                  = tcm_vhost_close_session,
2033         .sess_get_index                 = tcm_vhost_sess_get_index,
2034         .sess_get_initiator_sid         = NULL,
2035         .write_pending                  = tcm_vhost_write_pending,
2036         .write_pending_status           = tcm_vhost_write_pending_status,
2037         .set_default_node_attributes    = tcm_vhost_set_default_node_attrs,
2038         .get_task_tag                   = tcm_vhost_get_task_tag,
2039         .get_cmd_state                  = tcm_vhost_get_cmd_state,
2040         .queue_data_in                  = tcm_vhost_queue_data_in,
2041         .queue_status                   = tcm_vhost_queue_status,
2042         .queue_tm_rsp                   = tcm_vhost_queue_tm_rsp,
2043         /*
2044          * Setup callers for generic logic in target_core_fabric_configfs.c
2045          */
2046         .fabric_make_wwn                = tcm_vhost_make_tport,
2047         .fabric_drop_wwn                = tcm_vhost_drop_tport,
2048         .fabric_make_tpg                = tcm_vhost_make_tpg,
2049         .fabric_drop_tpg                = tcm_vhost_drop_tpg,
2050         .fabric_post_link               = tcm_vhost_port_link,
2051         .fabric_pre_unlink              = tcm_vhost_port_unlink,
2052         .fabric_make_np                 = NULL,
2053         .fabric_drop_np                 = NULL,
2054         .fabric_make_nodeacl            = tcm_vhost_make_nodeacl,
2055         .fabric_drop_nodeacl            = tcm_vhost_drop_nodeacl,
2056 };
2057
2058 static int tcm_vhost_register_configfs(void)
2059 {
2060         struct target_fabric_configfs *fabric;
2061         int ret;
2062
2063         pr_debug("TCM_VHOST fabric module %s on %s/%s"
2064                 " on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname,
2065                 utsname()->machine);
2066         /*
2067          * Register the top level struct config_item_type with TCM core
2068          */
2069         fabric = target_fabric_configfs_init(THIS_MODULE, "vhost");
2070         if (IS_ERR(fabric)) {
2071                 pr_err("target_fabric_configfs_init() failed\n");
2072                 return PTR_ERR(fabric);
2073         }
2074         /*
2075          * Setup fabric->tf_ops from our local tcm_vhost_ops
2076          */
2077         fabric->tf_ops = tcm_vhost_ops;
2078         /*
2079          * Setup default attribute lists for various fabric->tf_cit_tmpl
2080          */
2081         TF_CIT_TMPL(fabric)->tfc_wwn_cit.ct_attrs = tcm_vhost_wwn_attrs;
2082         TF_CIT_TMPL(fabric)->tfc_tpg_base_cit.ct_attrs = tcm_vhost_tpg_attrs;
2083         TF_CIT_TMPL(fabric)->tfc_tpg_attrib_cit.ct_attrs = NULL;
2084         TF_CIT_TMPL(fabric)->tfc_tpg_param_cit.ct_attrs = NULL;
2085         TF_CIT_TMPL(fabric)->tfc_tpg_np_base_cit.ct_attrs = NULL;
2086         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_base_cit.ct_attrs = NULL;
2087         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_attrib_cit.ct_attrs = NULL;
2088         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_auth_cit.ct_attrs = NULL;
2089         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_param_cit.ct_attrs = NULL;
2090         /*
2091          * Register the fabric for use within TCM
2092          */
2093         ret = target_fabric_configfs_register(fabric);
2094         if (ret < 0) {
2095                 pr_err("target_fabric_configfs_register() failed"
2096                                 " for TCM_VHOST\n");
2097                 return ret;
2098         }
2099         /*
2100          * Setup our local pointer to *fabric
2101          */
2102         tcm_vhost_fabric_configfs = fabric;
2103         pr_debug("TCM_VHOST[0] - Set fabric -> tcm_vhost_fabric_configfs\n");
2104         return 0;
2105 };
2106
2107 static void tcm_vhost_deregister_configfs(void)
2108 {
2109         if (!tcm_vhost_fabric_configfs)
2110                 return;
2111
2112         target_fabric_configfs_deregister(tcm_vhost_fabric_configfs);
2113         tcm_vhost_fabric_configfs = NULL;
2114         pr_debug("TCM_VHOST[0] - Cleared tcm_vhost_fabric_configfs\n");
2115 };
2116
2117 static int __init tcm_vhost_init(void)
2118 {
2119         int ret = -ENOMEM;
2120         /*
2121          * Use our own dedicated workqueue for submitting I/O into
2122          * target core to avoid contention within system_wq.
2123          */
2124         tcm_vhost_workqueue = alloc_workqueue("tcm_vhost", 0, 0);
2125         if (!tcm_vhost_workqueue)
2126                 goto out;
2127
2128         ret = vhost_scsi_register();
2129         if (ret < 0)
2130                 goto out_destroy_workqueue;
2131
2132         ret = tcm_vhost_register_configfs();
2133         if (ret < 0)
2134                 goto out_vhost_scsi_deregister;
2135
2136         return 0;
2137
2138 out_vhost_scsi_deregister:
2139         vhost_scsi_deregister();
2140 out_destroy_workqueue:
2141         destroy_workqueue(tcm_vhost_workqueue);
2142 out:
2143         return ret;
2144 };
2145
2146 static void tcm_vhost_exit(void)
2147 {
2148         tcm_vhost_deregister_configfs();
2149         vhost_scsi_deregister();
2150         destroy_workqueue(tcm_vhost_workqueue);
2151 };
2152
2153 MODULE_DESCRIPTION("VHOST_SCSI series fabric driver");
2154 MODULE_ALIAS("tcm_vhost");
2155 MODULE_LICENSE("GPL");
2156 module_init(tcm_vhost_init);
2157 module_exit(tcm_vhost_exit);