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         struct tcm_vhost_cmd *tv_cmd = container_of(se_cmd,
 452                                 struct tcm_vhost_cmd, tvc_se_cmd);
 453
 454         if (tv_cmd->tvc_sgl_count) {
 455                 u32 i;
 456                 for (i = 0; i < tv_cmd->tvc_sgl_count; i++)
 457                         put_page(sg_page(&tv_cmd->tvc_sgl[i]));
 458
 459                 kfree(tv_cmd->tvc_sgl);
 460         }
 461
 462         tcm_vhost_put_inflight(tv_cmd->inflight);
 463         kfree(tv_cmd);
 464 }
 465
 466 static int tcm_vhost_shutdown_session(struct se_session *se_sess)
 467 {
 468         return 0;
 469 }
 470
 471 static void tcm_vhost_close_session(struct se_session *se_sess)
 472 {
 473         return;
 474 }
 475
 476 static u32 tcm_vhost_sess_get_index(struct se_session *se_sess)
 477 {
 478         return 0;
 479 }
 480
 481 static int tcm_vhost_write_pending(struct se_cmd *se_cmd)
 482 {
 483         /* Go ahead and process the write immediately */
 484         target_execute_cmd(se_cmd);
 485         return 0;
 486 }
 487
 488 static int tcm_vhost_write_pending_status(struct se_cmd *se_cmd)
 489 {
 490         return 0;
 491 }
 492
 493 static void tcm_vhost_set_default_node_attrs(struct se_node_acl *nacl)
 494 {
 495         return;
 496 }
 497
 498 static u32 tcm_vhost_get_task_tag(struct se_cmd *se_cmd)
 499 {
 500         return 0;
 501 }
 502
 503 static int tcm_vhost_get_cmd_state(struct se_cmd *se_cmd)
 504 {
 505         return 0;
 506 }
 507
 508 static void vhost_scsi_complete_cmd(struct tcm_vhost_cmd *cmd)
 509 {
 510         struct vhost_scsi *vs = cmd->tvc_vhost;
 511
 512         llist_add(&cmd->tvc_completion_list, &vs->vs_completion_list);
 513
 514         vhost_work_queue(&vs->dev, &vs->vs_completion_work);
 515 }
 516
 517 static int tcm_vhost_queue_data_in(struct se_cmd *se_cmd)
 518 {
 519         struct tcm_vhost_cmd *cmd = container_of(se_cmd,
 520                                 struct tcm_vhost_cmd, tvc_se_cmd);
 521         vhost_scsi_complete_cmd(cmd);
 522         return 0;
 523 }
 524
 525 static int tcm_vhost_queue_status(struct se_cmd *se_cmd)
 526 {
 527         struct tcm_vhost_cmd *cmd = container_of(se_cmd,
 528                                 struct tcm_vhost_cmd, tvc_se_cmd);
 529         vhost_scsi_complete_cmd(cmd);
 530         return 0;
 531 }
 532
 533 static void tcm_vhost_queue_tm_rsp(struct se_cmd *se_cmd)
 534 {
 535         return;
 536 }
 537
 538 static void tcm_vhost_free_evt(struct vhost_scsi *vs, struct tcm_vhost_evt *evt)
 539 {
 540         vs->vs_events_nr--;
 541         kfree(evt);
 542 }
 543
 544 static struct tcm_vhost_evt *
 545 tcm_vhost_allocate_evt(struct vhost_scsi *vs,
 546                        u32 event, u32 reason)
 547 {
 548         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 549         struct tcm_vhost_evt *evt;
 550
 551         if (vs->vs_events_nr > VHOST_SCSI_MAX_EVENT) {
 552                 vs->vs_events_missed = true;
 553                 return NULL;
 554         }
 555
 556         evt = kzalloc(sizeof(*evt), GFP_KERNEL);
 557         if (!evt) {
 558                 vq_err(vq, "Failed to allocate tcm_vhost_evt\n");
 559                 vs->vs_events_missed = true;
 560                 return NULL;
 561         }
 562
 563         evt->event.event = event;
 564         evt->event.reason = reason;
 565         vs->vs_events_nr++;
 566
 567         return evt;
 568 }
 569
 570 static void vhost_scsi_free_cmd(struct tcm_vhost_cmd *cmd)
 571 {
 572         struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
 573
 574         /* TODO locking against target/backend threads? */
 575         transport_generic_free_cmd(se_cmd, 0);
 576
 577 }
 578
 579 static int vhost_scsi_check_stop_free(struct se_cmd *se_cmd)
 580 {
 581         return target_put_sess_cmd(se_cmd->se_sess, se_cmd);
 582 }
 583
 584 static void
 585 tcm_vhost_do_evt_work(struct vhost_scsi *vs, struct tcm_vhost_evt *evt)
 586 {
 587         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 588         struct virtio_scsi_event *event = &evt->event;
 589         struct virtio_scsi_event __user *eventp;
 590         unsigned out, in;
 591         int head, ret;
 592
 593         if (!vq->private_data) {
 594                 vs->vs_events_missed = true;
 595                 return;
 596         }
 597
 598 again:
 599         vhost_disable_notify(&vs->dev, vq);
 600         head = vhost_get_vq_desc(&vs->dev, vq, vq->iov,
 601                         ARRAY_SIZE(vq->iov), &out, &in,
 602                         NULL, NULL);
 603         if (head < 0) {
 604                 vs->vs_events_missed = true;
 605                 return;
 606         }
 607         if (head == vq->num) {
 608                 if (vhost_enable_notify(&vs->dev, vq))
 609                         goto again;
 610                 vs->vs_events_missed = true;
 611                 return;
 612         }
 613
 614         if ((vq->iov[out].iov_len != sizeof(struct virtio_scsi_event))) {
 615                 vq_err(vq, "Expecting virtio_scsi_event, got %zu bytes\n",
 616                                 vq->iov[out].iov_len);
 617                 vs->vs_events_missed = true;
 618                 return;
 619         }
 620
 621         if (vs->vs_events_missed) {
 622                 event->event |= VIRTIO_SCSI_T_EVENTS_MISSED;
 623                 vs->vs_events_missed = false;
 624         }
 625
 626         eventp = vq->iov[out].iov_base;
 627         ret = __copy_to_user(eventp, event, sizeof(*event));
 628         if (!ret)
 629                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 630         else
 631                 vq_err(vq, "Faulted on tcm_vhost_send_event\n");
 632 }
 633
 634 static void tcm_vhost_evt_work(struct vhost_work *work)
 635 {
 636         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 637                                         vs_event_work);
 638         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 639         struct tcm_vhost_evt *evt;
 640         struct llist_node *llnode;
 641
 642         mutex_lock(&vq->mutex);
 643         llnode = llist_del_all(&vs->vs_event_list);
 644         while (llnode) {
 645                 evt = llist_entry(llnode, struct tcm_vhost_evt, list);
 646                 llnode = llist_next(llnode);
 647                 tcm_vhost_do_evt_work(vs, evt);
 648                 tcm_vhost_free_evt(vs, evt);
 649         }
 650         mutex_unlock(&vq->mutex);
 651 }
 652
 653 /* Fill in status and signal that we are done processing this command
 654  *
 655  * This is scheduled in the vhost work queue so we are called with the owner
 656  * process mm and can access the vring.
 657  */
 658 static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
 659 {
 660         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 661                                         vs_completion_work);
 662         DECLARE_BITMAP(signal, VHOST_SCSI_MAX_VQ);
 663         struct virtio_scsi_cmd_resp v_rsp;
 664         struct tcm_vhost_cmd *cmd;
 665         struct llist_node *llnode;
 666         struct se_cmd *se_cmd;
 667         int ret, vq;
 668
 669         bitmap_zero(signal, VHOST_SCSI_MAX_VQ);
 670         llnode = llist_del_all(&vs->vs_completion_list);
 671         while (llnode) {
 672                 cmd = llist_entry(llnode, struct tcm_vhost_cmd,
 673                                      tvc_completion_list);
 674                 llnode = llist_next(llnode);
 675                 se_cmd = &cmd->tvc_se_cmd;
 676
 677                 pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__,
 678                         cmd, se_cmd->residual_count, se_cmd->scsi_status);
 679
 680                 memset(&v_rsp, 0, sizeof(v_rsp));
 681                 v_rsp.resid = se_cmd->residual_count;
 682                 /* TODO is status_qualifier field needed? */
 683                 v_rsp.status = se_cmd->scsi_status;
 684                 v_rsp.sense_len = se_cmd->scsi_sense_length;
 685                 memcpy(v_rsp.sense, cmd->tvc_sense_buf,
 686                        v_rsp.sense_len);
 687                 ret = copy_to_user(cmd->tvc_resp, &v_rsp, sizeof(v_rsp));
 688                 if (likely(ret == 0)) {
 689                         struct vhost_scsi_virtqueue *q;
 690                         vhost_add_used(cmd->tvc_vq, cmd->tvc_vq_desc, 0);
 691                         q = container_of(cmd->tvc_vq, struct vhost_scsi_virtqueue, vq);
 692                         vq = q - vs->vqs;
 693                         __set_bit(vq, signal);
 694                 } else
 695                         pr_err("Faulted on virtio_scsi_cmd_resp\n");
 696
 697                 vhost_scsi_free_cmd(cmd);
 698         }
 699
 700         vq = -1;
 701         while ((vq = find_next_bit(signal, VHOST_SCSI_MAX_VQ, vq + 1))
 702                 < VHOST_SCSI_MAX_VQ)
 703                 vhost_signal(&vs->dev, &vs->vqs[vq].vq);
 704 }
 705
 706 static struct tcm_vhost_cmd *
 707 vhost_scsi_allocate_cmd(struct vhost_virtqueue *vq,
 708                         struct tcm_vhost_tpg *tpg,
 709                         struct virtio_scsi_cmd_req *v_req,
 710                         u32 exp_data_len,
 711                         int data_direction)
 712 {
 713         struct tcm_vhost_cmd *cmd;
 714         struct tcm_vhost_nexus *tv_nexus;
 715
 716         tv_nexus = tpg->tpg_nexus;
 717         if (!tv_nexus) {
 718                 pr_err("Unable to locate active struct tcm_vhost_nexus\n");
 719                 return ERR_PTR(-EIO);
 720         }
 721
 722         cmd = kzalloc(sizeof(struct tcm_vhost_cmd), GFP_ATOMIC);
 723         if (!cmd) {
 724                 pr_err("Unable to allocate struct tcm_vhost_cmd\n");
 725                 return ERR_PTR(-ENOMEM);
 726         }
 727         cmd->tvc_tag = v_req->tag;
 728         cmd->tvc_task_attr = v_req->task_attr;
 729         cmd->tvc_exp_data_len = exp_data_len;
 730         cmd->tvc_data_direction = data_direction;
 731         cmd->tvc_nexus = tv_nexus;
 732         cmd->inflight = tcm_vhost_get_inflight(vq);
 733
 734         return cmd;
 735 }
 736
 737 /*
 738  * Map a user memory range into a scatterlist
 739  *
 740  * Returns the number of scatterlist entries used or -errno on error.
 741  */
 742 static int
 743 vhost_scsi_map_to_sgl(struct scatterlist *sgl,
 744                       unsigned int sgl_count,
 745                       struct iovec *iov,
 746                       int write)
 747 {
 748         unsigned int npages = 0, pages_nr, offset, nbytes;
 749         struct scatterlist *sg = sgl;
 750         void __user *ptr = iov->iov_base;
 751         size_t len = iov->iov_len;
 752         struct page **pages;
 753         int ret, i;
 754
 755         pages_nr = iov_num_pages(iov);
 756         if (pages_nr > sgl_count)
 757                 return -ENOBUFS;
 758
 759         pages = kmalloc(pages_nr * sizeof(struct page *), GFP_KERNEL);
 760         if (!pages)
 761                 return -ENOMEM;
 762
 763         ret = get_user_pages_fast((unsigned long)ptr, pages_nr, write, pages);
 764         /* No pages were pinned */
 765         if (ret < 0)
 766                 goto out;
 767         /* Less pages pinned than wanted */
 768         if (ret != pages_nr) {
 769                 for (i = 0; i < ret; i++)
 770                         put_page(pages[i]);
 771                 ret = -EFAULT;
 772                 goto out;
 773         }
 774
 775         while (len > 0) {
 776                 offset = (uintptr_t)ptr & ~PAGE_MASK;
 777                 nbytes = min_t(unsigned int, PAGE_SIZE - offset, len);
 778                 sg_set_page(sg, pages[npages], nbytes, offset);
 779                 ptr += nbytes;
 780                 len -= nbytes;
 781                 sg++;
 782                 npages++;
 783         }
 784
 785 out:
 786         kfree(pages);
 787         return ret;
 788 }
 789
 790 static int
 791 vhost_scsi_map_iov_to_sgl(struct tcm_vhost_cmd *cmd,
 792                           struct iovec *iov,
 793                           unsigned int niov,
 794                           int write)
 795 {
 796         int ret;
 797         unsigned int i;
 798         u32 sgl_count;
 799         struct scatterlist *sg;
 800
 801         /*
 802          * Find out how long sglist needs to be
 803          */
 804         sgl_count = 0;
 805         for (i = 0; i < niov; i++)
 806                 sgl_count += iov_num_pages(&iov[i]);
 807
 808         /* TODO overflow checking */
 809
 810         sg = kmalloc(sizeof(cmd->tvc_sgl[0]) * sgl_count, GFP_ATOMIC);
 811         if (!sg)
 812                 return -ENOMEM;
 813         pr_debug("%s sg %p sgl_count %u is_err %d\n", __func__,
 814                sg, sgl_count, !sg);
 815         sg_init_table(sg, sgl_count);
 816
 817         cmd->tvc_sgl = sg;
 818         cmd->tvc_sgl_count = sgl_count;
 819
 820         pr_debug("Mapping %u iovecs for %u pages\n", niov, sgl_count);
 821         for (i = 0; i < niov; i++) {
 822                 ret = vhost_scsi_map_to_sgl(sg, sgl_count, &iov[i], write);
 823                 if (ret < 0) {
 824                         for (i = 0; i < cmd->tvc_sgl_count; i++)
 825                                 put_page(sg_page(&cmd->tvc_sgl[i]));
 826                         kfree(cmd->tvc_sgl);
 827                         cmd->tvc_sgl = NULL;
 828                         cmd->tvc_sgl_count = 0;
 829                         return ret;
 830                 }
 831
 832                 sg += ret;
 833                 sgl_count -= ret;
 834         }
 835         return 0;
 836 }
 837
 838 static void tcm_vhost_submission_work(struct work_struct *work)
 839 {
 840         struct tcm_vhost_cmd *cmd =
 841                 container_of(work, struct tcm_vhost_cmd, work);
 842         struct tcm_vhost_nexus *tv_nexus;
 843         struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
 844         struct scatterlist *sg_ptr, *sg_bidi_ptr = NULL;
 845         int rc, sg_no_bidi = 0;
 846
 847         if (cmd->tvc_sgl_count) {
 848                 sg_ptr = cmd->tvc_sgl;
 849 /* FIXME: Fix BIDI operation in tcm_vhost_submission_work() */
 850 #if 0
 851                 if (se_cmd->se_cmd_flags & SCF_BIDI) {
 852                         sg_bidi_ptr = NULL;
 853                         sg_no_bidi = 0;
 854                 }
 855 #endif
 856         } else {
 857                 sg_ptr = NULL;
 858         }
 859         tv_nexus = cmd->tvc_nexus;
 860
 861         rc = target_submit_cmd_map_sgls(se_cmd, tv_nexus->tvn_se_sess,
 862                         cmd->tvc_cdb, &cmd->tvc_sense_buf[0],
 863                         cmd->tvc_lun, cmd->tvc_exp_data_len,
 864                         cmd->tvc_task_attr, cmd->tvc_data_direction,
 865                         TARGET_SCF_ACK_KREF, sg_ptr, cmd->tvc_sgl_count,
 866                         sg_bidi_ptr, sg_no_bidi);
 867         if (rc < 0) {
 868                 transport_send_check_condition_and_sense(se_cmd,
 869                                 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
 870                 transport_generic_free_cmd(se_cmd, 0);
 871         }
 872 }
 873
 874 static void
 875 vhost_scsi_send_bad_target(struct vhost_scsi *vs,
 876                            struct vhost_virtqueue *vq,
 877                            int head, unsigned out)
 878 {
 879         struct virtio_scsi_cmd_resp __user *resp;
 880         struct virtio_scsi_cmd_resp rsp;
 881         int ret;
 882
 883         memset(&rsp, 0, sizeof(rsp));
 884         rsp.response = VIRTIO_SCSI_S_BAD_TARGET;
 885         resp = vq->iov[out].iov_base;
 886         ret = __copy_to_user(resp, &rsp, sizeof(rsp));
 887         if (!ret)
 888                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 889         else
 890                 pr_err("Faulted on virtio_scsi_cmd_resp\n");
 891 }
 892
 893 static void
 894 vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
 895 {
 896         struct tcm_vhost_tpg **vs_tpg;
 897         struct virtio_scsi_cmd_req v_req;
 898         struct tcm_vhost_tpg *tpg;
 899         struct tcm_vhost_cmd *cmd;
 900         u32 exp_data_len, data_first, data_num, data_direction;
 901         unsigned out, in, i;
 902         int head, ret;
 903         u8 target;
 904
 905         mutex_lock(&vq->mutex);
 906         /*
 907          * We can handle the vq only after the endpoint is setup by calling the
 908          * VHOST_SCSI_SET_ENDPOINT ioctl.
 909          */
 910         vs_tpg = vq->private_data;
 911         if (!vs_tpg)
 912                 goto out;
 913
 914         vhost_disable_notify(&vs->dev, vq);
 915
 916         for (;;) {
 917                 head = vhost_get_vq_desc(&vs->dev, vq, vq->iov,
 918                                         ARRAY_SIZE(vq->iov), &out, &in,
 919                                         NULL, NULL);
 920                 pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n",
 921                                         head, out, in);
 922                 /* On error, stop handling until the next kick. */
 923                 if (unlikely(head < 0))
 924                         break;
 925                 /* Nothing new?  Wait for eventfd to tell us they refilled. */
 926                 if (head == vq->num) {
 927                         if (unlikely(vhost_enable_notify(&vs->dev, vq))) {
 928                                 vhost_disable_notify(&vs->dev, vq);
 929                                 continue;
 930                         }
 931                         break;
 932                 }
 933
 934 /* FIXME: BIDI operation */
 935                 if (out == 1 && in == 1) {
 936                         data_direction = DMA_NONE;
 937                         data_first = 0;
 938                         data_num = 0;
 939                 } else if (out == 1 && in > 1) {
 940                         data_direction = DMA_FROM_DEVICE;
 941                         data_first = out + 1;
 942                         data_num = in - 1;
 943                 } else if (out > 1 && in == 1) {
 944                         data_direction = DMA_TO_DEVICE;
 945                         data_first = 1;
 946                         data_num = out - 1;
 947                 } else {
 948                         vq_err(vq, "Invalid buffer layout out: %u in: %u\n",
 949                                         out, in);
 950                         break;
 951                 }
 952
 953                 /*
 954                  * Check for a sane resp buffer so we can report errors to
 955                  * the guest.
 956                  */
 957                 if (unlikely(vq->iov[out].iov_len !=
 958                                         sizeof(struct virtio_scsi_cmd_resp))) {
 959                         vq_err(vq, "Expecting virtio_scsi_cmd_resp, got %zu"
 960                                 " bytes\n", vq->iov[out].iov_len);
 961                         break;
 962                 }
 963
 964                 if (unlikely(vq->iov[0].iov_len != sizeof(v_req))) {
 965                         vq_err(vq, "Expecting virtio_scsi_cmd_req, got %zu"
 966                                 " bytes\n", vq->iov[0].iov_len);
 967                         break;
 968                 }
 969                 pr_debug("Calling __copy_from_user: vq->iov[0].iov_base: %p,"
 970                         " len: %zu\n", vq->iov[0].iov_base, sizeof(v_req));
 971                 ret = __copy_from_user(&v_req, vq->iov[0].iov_base,
 972                                 sizeof(v_req));
 973                 if (unlikely(ret)) {
 974                         vq_err(vq, "Faulted on virtio_scsi_cmd_req\n");
 975                         break;
 976                 }
 977
 978                 /* Extract the tpgt */
 979                 target = v_req.lun[1];
 980                 tpg = ACCESS_ONCE(vs_tpg[target]);
 981
 982                 /* Target does not exist, fail the request */
 983                 if (unlikely(!tpg)) {
 984                         vhost_scsi_send_bad_target(vs, vq, head, out);
 985                         continue;
 986                 }
 987
 988                 exp_data_len = 0;
 989                 for (i = 0; i < data_num; i++)
 990                         exp_data_len += vq->iov[data_first + i].iov_len;
 991
 992                 cmd = vhost_scsi_allocate_cmd(vq, tpg, &v_req,
 993                                         exp_data_len, data_direction);
 994                 if (IS_ERR(cmd)) {
 995                         vq_err(vq, "vhost_scsi_allocate_cmd failed %ld\n",
 996                                         PTR_ERR(cmd));
 997                         goto err_cmd;
 998                 }
 999                 pr_debug("Allocated tv_cmd: %p exp_data_len: %d, data_direction"
1000                         ": %d\n", cmd, exp_data_len, data_direction);
1001
1002                 cmd->tvc_vhost = vs;
1003                 cmd->tvc_vq = vq;
1004                 cmd->tvc_resp = vq->iov[out].iov_base;
1005
1006                 /*
1007                  * Copy in the recieved CDB descriptor into cmd->tvc_cdb
1008                  * that will be used by tcm_vhost_new_cmd_map() and down into
1009                  * target_setup_cmd_from_cdb()
1010                  */
1011                 memcpy(cmd->tvc_cdb, v_req.cdb, TCM_VHOST_MAX_CDB_SIZE);
1012                 /*
1013                  * Check that the recieved CDB size does not exceeded our
1014                  * hardcoded max for tcm_vhost
1015                  */
1016                 /* TODO what if cdb was too small for varlen cdb header? */
1017                 if (unlikely(scsi_command_size(cmd->tvc_cdb) >
1018                                         TCM_VHOST_MAX_CDB_SIZE)) {
1019                         vq_err(vq, "Received SCSI CDB with command_size: %d that"
1020                                 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1021                                 scsi_command_size(cmd->tvc_cdb),
1022                                 TCM_VHOST_MAX_CDB_SIZE);
1023                         goto err_free;
1024                 }
1025                 cmd->tvc_lun = ((v_req.lun[2] << 8) | v_req.lun[3]) & 0x3FFF;
1026
1027                 pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n",
1028                         cmd->tvc_cdb[0], cmd->tvc_lun);
1029
1030                 if (data_direction != DMA_NONE) {
1031                         ret = vhost_scsi_map_iov_to_sgl(cmd,
1032                                         &vq->iov[data_first], data_num,
1033                                         data_direction == DMA_TO_DEVICE);
1034                         if (unlikely(ret)) {
1035                                 vq_err(vq, "Failed to map iov to sgl\n");
1036                                 goto err_free;
1037                         }
1038                 }
1039
1040                 /*
1041                  * Save the descriptor from vhost_get_vq_desc() to be used to
1042                  * complete the virtio-scsi request in TCM callback context via
1043                  * tcm_vhost_queue_data_in() and tcm_vhost_queue_status()
1044                  */
1045                 cmd->tvc_vq_desc = head;
1046                 /*
1047                  * Dispatch tv_cmd descriptor for cmwq execution in process
1048                  * context provided by tcm_vhost_workqueue.  This also ensures
1049                  * tv_cmd is executed on the same kworker CPU as this vhost
1050                  * thread to gain positive L2 cache locality effects..
1051                  */
1052                 INIT_WORK(&cmd->work, tcm_vhost_submission_work);
1053                 queue_work(tcm_vhost_workqueue, &cmd->work);
1054         }
1055
1056         mutex_unlock(&vq->mutex);
1057         return;
1058
1059 err_free:
1060         vhost_scsi_free_cmd(cmd);
1061 err_cmd:
1062         vhost_scsi_send_bad_target(vs, vq, head, out);
1063 out:
1064         mutex_unlock(&vq->mutex);
1065 }
1066
1067 static void vhost_scsi_ctl_handle_kick(struct vhost_work *work)
1068 {
1069         pr_debug("%s: The handling func for control queue.\n", __func__);
1070 }
1071
1072 static void
1073 tcm_vhost_send_evt(struct vhost_scsi *vs,
1074                    struct tcm_vhost_tpg *tpg,
1075                    struct se_lun *lun,
1076                    u32 event,
1077                    u32 reason)
1078 {
1079         struct tcm_vhost_evt *evt;
1080
1081         evt = tcm_vhost_allocate_evt(vs, event, reason);
1082         if (!evt)
1083                 return;
1084
1085         if (tpg && lun) {
1086                 /* TODO: share lun setup code with virtio-scsi.ko */
1087                 /*
1088                  * Note: evt->event is zeroed when we allocate it and
1089                  * lun[4-7] need to be zero according to virtio-scsi spec.
1090                  */
1091                 evt->event.lun[0] = 0x01;
1092                 evt->event.lun[1] = tpg->tport_tpgt & 0xFF;
1093                 if (lun->unpacked_lun >= 256)
1094                         evt->event.lun[2] = lun->unpacked_lun >> 8 | 0x40 ;
1095                 evt->event.lun[3] = lun->unpacked_lun & 0xFF;
1096         }
1097
1098         llist_add(&evt->list, &vs->vs_event_list);
1099         vhost_work_queue(&vs->dev, &vs->vs_event_work);
1100 }
1101
1102 static void vhost_scsi_evt_handle_kick(struct vhost_work *work)
1103 {
1104         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1105                                                 poll.work);
1106         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1107
1108         mutex_lock(&vq->mutex);
1109         if (!vq->private_data)
1110                 goto out;
1111
1112         if (vs->vs_events_missed)
1113                 tcm_vhost_send_evt(vs, NULL, NULL, VIRTIO_SCSI_T_NO_EVENT, 0);
1114 out:
1115         mutex_unlock(&vq->mutex);
1116 }
1117
1118 static void vhost_scsi_handle_kick(struct vhost_work *work)
1119 {
1120         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1121                                                 poll.work);
1122         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1123
1124         vhost_scsi_handle_vq(vs, vq);
1125 }
1126
1127 static void vhost_scsi_flush_vq(struct vhost_scsi *vs, int index)
1128 {
1129         vhost_poll_flush(&vs->vqs[index].vq.poll);
1130 }
1131
1132 /* Callers must hold dev mutex */
1133 static void vhost_scsi_flush(struct vhost_scsi *vs)
1134 {
1135         struct vhost_scsi_inflight *old_inflight[VHOST_SCSI_MAX_VQ];
1136         int i;
1137
1138         /* Init new inflight and remember the old inflight */
1139         tcm_vhost_init_inflight(vs, old_inflight);
1140
1141         /*
1142          * The inflight->kref was initialized to 1. We decrement it here to
1143          * indicate the start of the flush operation so that it will reach 0
1144          * when all the reqs are finished.
1145          */
1146         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1147                 kref_put(&old_inflight[i]->kref, tcm_vhost_done_inflight);
1148
1149         /* Flush both the vhost poll and vhost work */
1150         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1151                 vhost_scsi_flush_vq(vs, i);
1152         vhost_work_flush(&vs->dev, &vs->vs_completion_work);
1153         vhost_work_flush(&vs->dev, &vs->vs_event_work);
1154
1155         /* Wait for all reqs issued before the flush to be finished */
1156         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1157                 wait_for_completion(&old_inflight[i]->comp);
1158 }
1159
1160 /*
1161  * Called from vhost_scsi_ioctl() context to walk the list of available
1162  * tcm_vhost_tpg with an active struct tcm_vhost_nexus
1163  *
1164  *  The lock nesting rule is:
1165  *    tcm_vhost_mutex -> vs->dev.mutex -> tpg->tv_tpg_mutex -> vq->mutex
1166  */
1167 static int
1168 vhost_scsi_set_endpoint(struct vhost_scsi *vs,
1169                         struct vhost_scsi_target *t)
1170 {
1171         struct tcm_vhost_tport *tv_tport;
1172         struct tcm_vhost_tpg *tpg;
1173         struct tcm_vhost_tpg **vs_tpg;
1174         struct vhost_virtqueue *vq;
1175         int index, ret, i, len;
1176         bool match = false;
1177
1178         mutex_lock(&tcm_vhost_mutex);
1179         mutex_lock(&vs->dev.mutex);
1180
1181         /* Verify that ring has been setup correctly. */
1182         for (index = 0; index < vs->dev.nvqs; ++index) {
1183                 /* Verify that ring has been setup correctly. */
1184                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1185                         ret = -EFAULT;
1186                         goto out;
1187                 }
1188         }
1189
1190         len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET;
1191         vs_tpg = kzalloc(len, GFP_KERNEL);
1192         if (!vs_tpg) {
1193                 ret = -ENOMEM;
1194                 goto out;
1195         }
1196         if (vs->vs_tpg)
1197                 memcpy(vs_tpg, vs->vs_tpg, len);
1198
1199         list_for_each_entry(tpg, &tcm_vhost_list, tv_tpg_list) {
1200                 mutex_lock(&tpg->tv_tpg_mutex);
1201                 if (!tpg->tpg_nexus) {
1202                         mutex_unlock(&tpg->tv_tpg_mutex);
1203                         continue;
1204                 }
1205                 if (tpg->tv_tpg_vhost_count != 0) {
1206                         mutex_unlock(&tpg->tv_tpg_mutex);
1207                         continue;
1208                 }
1209                 tv_tport = tpg->tport;
1210
1211                 if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1212                         if (vs->vs_tpg && vs->vs_tpg[tpg->tport_tpgt]) {
1213                                 kfree(vs_tpg);
1214                                 mutex_unlock(&tpg->tv_tpg_mutex);
1215                                 ret = -EEXIST;
1216                                 goto out;
1217                         }
1218                         tpg->tv_tpg_vhost_count++;
1219                         tpg->vhost_scsi = vs;
1220                         vs_tpg[tpg->tport_tpgt] = tpg;
1221                         smp_mb__after_atomic_inc();
1222                         match = true;
1223                 }
1224                 mutex_unlock(&tpg->tv_tpg_mutex);
1225         }
1226
1227         if (match) {
1228                 memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
1229                        sizeof(vs->vs_vhost_wwpn));
1230                 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1231                         vq = &vs->vqs[i].vq;
1232                         mutex_lock(&vq->mutex);
1233                         vq->private_data = vs_tpg;
1234                         vhost_init_used(vq);
1235                         mutex_unlock(&vq->mutex);
1236                 }
1237                 ret = 0;
1238         } else {
1239                 ret = -EEXIST;
1240         }
1241
1242         /*
1243          * Act as synchronize_rcu to make sure access to
1244          * old vs->vs_tpg is finished.
1245          */
1246         vhost_scsi_flush(vs);
1247         kfree(vs->vs_tpg);
1248         vs->vs_tpg = vs_tpg;
1249
1250 out:
1251         mutex_unlock(&vs->dev.mutex);
1252         mutex_unlock(&tcm_vhost_mutex);
1253         return ret;
1254 }
1255
1256 static int
1257 vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
1258                           struct vhost_scsi_target *t)
1259 {
1260         struct tcm_vhost_tport *tv_tport;
1261         struct tcm_vhost_tpg *tpg;
1262         struct vhost_virtqueue *vq;
1263         bool match = false;
1264         int index, ret, i;
1265         u8 target;
1266
1267         mutex_lock(&tcm_vhost_mutex);
1268         mutex_lock(&vs->dev.mutex);
1269         /* Verify that ring has been setup correctly. */
1270         for (index = 0; index < vs->dev.nvqs; ++index) {
1271                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1272                         ret = -EFAULT;
1273                         goto err_dev;
1274                 }
1275         }
1276
1277         if (!vs->vs_tpg) {
1278                 ret = 0;
1279                 goto err_dev;
1280         }
1281
1282         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1283                 target = i;
1284                 tpg = vs->vs_tpg[target];
1285                 if (!tpg)
1286                         continue;
1287
1288                 mutex_lock(&tpg->tv_tpg_mutex);
1289                 tv_tport = tpg->tport;
1290                 if (!tv_tport) {
1291                         ret = -ENODEV;
1292                         goto err_tpg;
1293                 }
1294
1295                 if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1296                         pr_warn("tv_tport->tport_name: %s, tpg->tport_tpgt: %hu"
1297                                 " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
1298                                 tv_tport->tport_name, tpg->tport_tpgt,
1299                                 t->vhost_wwpn, t->vhost_tpgt);
1300                         ret = -EINVAL;
1301                         goto err_tpg;
1302                 }
1303                 tpg->tv_tpg_vhost_count--;
1304                 tpg->vhost_scsi = NULL;
1305                 vs->vs_tpg[target] = NULL;
1306                 match = true;
1307                 mutex_unlock(&tpg->tv_tpg_mutex);
1308         }
1309         if (match) {
1310                 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1311                         vq = &vs->vqs[i].vq;
1312                         mutex_lock(&vq->mutex);
1313                         vq->private_data = NULL;
1314                         mutex_unlock(&vq->mutex);
1315                 }
1316         }
1317         /*
1318          * Act as synchronize_rcu to make sure access to
1319          * old vs->vs_tpg is finished.
1320          */
1321         vhost_scsi_flush(vs);
1322         kfree(vs->vs_tpg);
1323         vs->vs_tpg = NULL;
1324         WARN_ON(vs->vs_events_nr);
1325         mutex_unlock(&vs->dev.mutex);
1326         mutex_unlock(&tcm_vhost_mutex);
1327         return 0;
1328
1329 err_tpg:
1330         mutex_unlock(&tpg->tv_tpg_mutex);
1331 err_dev:
1332         mutex_unlock(&vs->dev.mutex);
1333         mutex_unlock(&tcm_vhost_mutex);
1334         return ret;
1335 }
1336
1337 static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features)
1338 {
1339         if (features & ~VHOST_SCSI_FEATURES)
1340                 return -EOPNOTSUPP;
1341
1342         mutex_lock(&vs->dev.mutex);
1343         if ((features & (1 << VHOST_F_LOG_ALL)) &&
1344             !vhost_log_access_ok(&vs->dev)) {
1345                 mutex_unlock(&vs->dev.mutex);
1346                 return -EFAULT;
1347         }
1348         vs->dev.acked_features = features;
1349         smp_wmb();
1350         vhost_scsi_flush(vs);
1351         mutex_unlock(&vs->dev.mutex);
1352         return 0;
1353 }
1354
1355 static int vhost_scsi_open(struct inode *inode, struct file *f)
1356 {
1357         struct vhost_scsi *vs;
1358         struct vhost_virtqueue **vqs;
1359         int r, i;
1360
1361         vs = kzalloc(sizeof(*vs), GFP_KERNEL);
1362         if (!vs)
1363                 return -ENOMEM;
1364
1365         vqs = kmalloc(VHOST_SCSI_MAX_VQ * sizeof(*vqs), GFP_KERNEL);
1366         if (!vqs) {
1367                 kfree(vs);
1368                 return -ENOMEM;
1369         }
1370
1371         vhost_work_init(&vs->vs_completion_work, vhost_scsi_complete_cmd_work);
1372         vhost_work_init(&vs->vs_event_work, tcm_vhost_evt_work);
1373
1374         vs->vs_events_nr = 0;
1375         vs->vs_events_missed = false;
1376
1377         vqs[VHOST_SCSI_VQ_CTL] = &vs->vqs[VHOST_SCSI_VQ_CTL].vq;
1378         vqs[VHOST_SCSI_VQ_EVT] = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1379         vs->vqs[VHOST_SCSI_VQ_CTL].vq.handle_kick = vhost_scsi_ctl_handle_kick;
1380         vs->vqs[VHOST_SCSI_VQ_EVT].vq.handle_kick = vhost_scsi_evt_handle_kick;
1381         for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++) {
1382                 vqs[i] = &vs->vqs[i].vq;
1383                 vs->vqs[i].vq.handle_kick = vhost_scsi_handle_kick;
1384         }
1385         r = vhost_dev_init(&vs->dev, vqs, VHOST_SCSI_MAX_VQ);
1386
1387         tcm_vhost_init_inflight(vs, NULL);
1388
1389         if (r < 0) {
1390                 kfree(vqs);
1391                 kfree(vs);
1392                 return r;
1393         }
1394
1395         f->private_data = vs;
1396         return 0;
1397 }
1398
1399 static int vhost_scsi_release(struct inode *inode, struct file *f)
1400 {
1401         struct vhost_scsi *vs = f->private_data;
1402         struct vhost_scsi_target t;
1403
1404         mutex_lock(&vs->dev.mutex);
1405         memcpy(t.vhost_wwpn, vs->vs_vhost_wwpn, sizeof(t.vhost_wwpn));
1406         mutex_unlock(&vs->dev.mutex);
1407         vhost_scsi_clear_endpoint(vs, &t);
1408         vhost_dev_stop(&vs->dev);
1409         vhost_dev_cleanup(&vs->dev, false);
1410         /* Jobs can re-queue themselves in evt kick handler. Do extra flush. */
1411         vhost_scsi_flush(vs);
1412         kfree(vs->dev.vqs);
1413         kfree(vs);
1414         return 0;
1415 }
1416
1417 static long
1418 vhost_scsi_ioctl(struct file *f,
1419                  unsigned int ioctl,
1420                  unsigned long arg)
1421 {
1422         struct vhost_scsi *vs = f->private_data;
1423         struct vhost_scsi_target backend;
1424         void __user *argp = (void __user *)arg;
1425         u64 __user *featurep = argp;
1426         u32 __user *eventsp = argp;
1427         u32 events_missed;
1428         u64 features;
1429         int r, abi_version = VHOST_SCSI_ABI_VERSION;
1430         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1431
1432         switch (ioctl) {
1433         case VHOST_SCSI_SET_ENDPOINT:
1434                 if (copy_from_user(&backend, argp, sizeof backend))
1435                         return -EFAULT;
1436                 if (backend.reserved != 0)
1437                         return -EOPNOTSUPP;
1438
1439                 return vhost_scsi_set_endpoint(vs, &backend);
1440         case VHOST_SCSI_CLEAR_ENDPOINT:
1441                 if (copy_from_user(&backend, argp, sizeof backend))
1442                         return -EFAULT;
1443                 if (backend.reserved != 0)
1444                         return -EOPNOTSUPP;
1445
1446                 return vhost_scsi_clear_endpoint(vs, &backend);
1447         case VHOST_SCSI_GET_ABI_VERSION:
1448                 if (copy_to_user(argp, &abi_version, sizeof abi_version))
1449                         return -EFAULT;
1450                 return 0;
1451         case VHOST_SCSI_SET_EVENTS_MISSED:
1452                 if (get_user(events_missed, eventsp))
1453                         return -EFAULT;
1454                 mutex_lock(&vq->mutex);
1455                 vs->vs_events_missed = events_missed;
1456                 mutex_unlock(&vq->mutex);
1457                 return 0;
1458         case VHOST_SCSI_GET_EVENTS_MISSED:
1459                 mutex_lock(&vq->mutex);
1460                 events_missed = vs->vs_events_missed;
1461                 mutex_unlock(&vq->mutex);
1462                 if (put_user(events_missed, eventsp))
1463                         return -EFAULT;
1464                 return 0;
1465         case VHOST_GET_FEATURES:
1466                 features = VHOST_SCSI_FEATURES;
1467                 if (copy_to_user(featurep, &features, sizeof features))
1468                         return -EFAULT;
1469                 return 0;
1470         case VHOST_SET_FEATURES:
1471                 if (copy_from_user(&features, featurep, sizeof features))
1472                         return -EFAULT;
1473                 return vhost_scsi_set_features(vs, features);
1474         default:
1475                 mutex_lock(&vs->dev.mutex);
1476                 r = vhost_dev_ioctl(&vs->dev, ioctl, argp);
1477                 /* TODO: flush backend after dev ioctl. */
1478                 if (r == -ENOIOCTLCMD)
1479                         r = vhost_vring_ioctl(&vs->dev, ioctl, argp);
1480                 mutex_unlock(&vs->dev.mutex);
1481                 return r;
1482         }
1483 }
1484
1485 #ifdef CONFIG_COMPAT
1486 static long vhost_scsi_compat_ioctl(struct file *f, unsigned int ioctl,
1487                                 unsigned long arg)
1488 {
1489         return vhost_scsi_ioctl(f, ioctl, (unsigned long)compat_ptr(arg));
1490 }
1491 #endif
1492
1493 static const struct file_operations vhost_scsi_fops = {
1494         .owner          = THIS_MODULE,
1495         .release        = vhost_scsi_release,
1496         .unlocked_ioctl = vhost_scsi_ioctl,
1497 #ifdef CONFIG_COMPAT
1498         .compat_ioctl   = vhost_scsi_compat_ioctl,
1499 #endif
1500         .open           = vhost_scsi_open,
1501         .llseek         = noop_llseek,
1502 };
1503
1504 static struct miscdevice vhost_scsi_misc = {
1505         MISC_DYNAMIC_MINOR,
1506         "vhost-scsi",
1507         &vhost_scsi_fops,
1508 };
1509
1510 static int __init vhost_scsi_register(void)
1511 {
1512         return misc_register(&vhost_scsi_misc);
1513 }
1514
1515 static int vhost_scsi_deregister(void)
1516 {
1517         return misc_deregister(&vhost_scsi_misc);
1518 }
1519
1520 static char *tcm_vhost_dump_proto_id(struct tcm_vhost_tport *tport)
1521 {
1522         switch (tport->tport_proto_id) {
1523         case SCSI_PROTOCOL_SAS:
1524                 return "SAS";
1525         case SCSI_PROTOCOL_FCP:
1526                 return "FCP";
1527         case SCSI_PROTOCOL_ISCSI:
1528                 return "iSCSI";
1529         default:
1530                 break;
1531         }
1532
1533         return "Unknown";
1534 }
1535
1536 static void
1537 tcm_vhost_do_plug(struct tcm_vhost_tpg *tpg,
1538                   struct se_lun *lun, bool plug)
1539 {
1540
1541         struct vhost_scsi *vs = tpg->vhost_scsi;
1542         struct vhost_virtqueue *vq;
1543         u32 reason;
1544
1545         if (!vs)
1546                 return;
1547
1548         mutex_lock(&vs->dev.mutex);
1549         if (!vhost_has_feature(&vs->dev, VIRTIO_SCSI_F_HOTPLUG)) {
1550                 mutex_unlock(&vs->dev.mutex);
1551                 return;
1552         }
1553
1554         if (plug)
1555                 reason = VIRTIO_SCSI_EVT_RESET_RESCAN;
1556         else
1557                 reason = VIRTIO_SCSI_EVT_RESET_REMOVED;
1558
1559         vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1560         mutex_lock(&vq->mutex);
1561         tcm_vhost_send_evt(vs, tpg, lun,
1562                         VIRTIO_SCSI_T_TRANSPORT_RESET, reason);
1563         mutex_unlock(&vq->mutex);
1564         mutex_unlock(&vs->dev.mutex);
1565 }
1566
1567 static void tcm_vhost_hotplug(struct tcm_vhost_tpg *tpg, struct se_lun *lun)
1568 {
1569         tcm_vhost_do_plug(tpg, lun, true);
1570 }
1571
1572 static void tcm_vhost_hotunplug(struct tcm_vhost_tpg *tpg, struct se_lun *lun)
1573 {
1574         tcm_vhost_do_plug(tpg, lun, false);
1575 }
1576
1577 static int tcm_vhost_port_link(struct se_portal_group *se_tpg,
1578                                struct se_lun *lun)
1579 {
1580         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1581                                 struct tcm_vhost_tpg, se_tpg);
1582
1583         mutex_lock(&tcm_vhost_mutex);
1584
1585         mutex_lock(&tpg->tv_tpg_mutex);
1586         tpg->tv_tpg_port_count++;
1587         mutex_unlock(&tpg->tv_tpg_mutex);
1588
1589         tcm_vhost_hotplug(tpg, lun);
1590
1591         mutex_unlock(&tcm_vhost_mutex);
1592
1593         return 0;
1594 }
1595
1596 static void tcm_vhost_port_unlink(struct se_portal_group *se_tpg,
1597                                   struct se_lun *lun)
1598 {
1599         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1600                                 struct tcm_vhost_tpg, se_tpg);
1601
1602         mutex_lock(&tcm_vhost_mutex);
1603
1604         mutex_lock(&tpg->tv_tpg_mutex);
1605         tpg->tv_tpg_port_count--;
1606         mutex_unlock(&tpg->tv_tpg_mutex);
1607
1608         tcm_vhost_hotunplug(tpg, lun);
1609
1610         mutex_unlock(&tcm_vhost_mutex);
1611 }
1612
1613 static struct se_node_acl *
1614 tcm_vhost_make_nodeacl(struct se_portal_group *se_tpg,
1615                        struct config_group *group,
1616                        const char *name)
1617 {
1618         struct se_node_acl *se_nacl, *se_nacl_new;
1619         struct tcm_vhost_nacl *nacl;
1620         u64 wwpn = 0;
1621         u32 nexus_depth;
1622
1623         /* tcm_vhost_parse_wwn(name, &wwpn, 1) < 0)
1624                 return ERR_PTR(-EINVAL); */
1625         se_nacl_new = tcm_vhost_alloc_fabric_acl(se_tpg);
1626         if (!se_nacl_new)
1627                 return ERR_PTR(-ENOMEM);
1628
1629         nexus_depth = 1;
1630         /*
1631          * se_nacl_new may be released by core_tpg_add_initiator_node_acl()
1632          * when converting a NodeACL from demo mode -> explict
1633          */
1634         se_nacl = core_tpg_add_initiator_node_acl(se_tpg, se_nacl_new,
1635                                 name, nexus_depth);
1636         if (IS_ERR(se_nacl)) {
1637                 tcm_vhost_release_fabric_acl(se_tpg, se_nacl_new);
1638                 return se_nacl;
1639         }
1640         /*
1641          * Locate our struct tcm_vhost_nacl and set the FC Nport WWPN
1642          */
1643         nacl = container_of(se_nacl, struct tcm_vhost_nacl, se_node_acl);
1644         nacl->iport_wwpn = wwpn;
1645
1646         return se_nacl;
1647 }
1648
1649 static void tcm_vhost_drop_nodeacl(struct se_node_acl *se_acl)
1650 {
1651         struct tcm_vhost_nacl *nacl = container_of(se_acl,
1652                                 struct tcm_vhost_nacl, se_node_acl);
1653         core_tpg_del_initiator_node_acl(se_acl->se_tpg, se_acl, 1);
1654         kfree(nacl);
1655 }
1656
1657 static int tcm_vhost_make_nexus(struct tcm_vhost_tpg *tpg,
1658                                 const char *name)
1659 {
1660         struct se_portal_group *se_tpg;
1661         struct tcm_vhost_nexus *tv_nexus;
1662
1663         mutex_lock(&tpg->tv_tpg_mutex);
1664         if (tpg->tpg_nexus) {
1665                 mutex_unlock(&tpg->tv_tpg_mutex);
1666                 pr_debug("tpg->tpg_nexus already exists\n");
1667                 return -EEXIST;
1668         }
1669         se_tpg = &tpg->se_tpg;
1670
1671         tv_nexus = kzalloc(sizeof(struct tcm_vhost_nexus), GFP_KERNEL);
1672         if (!tv_nexus) {
1673                 mutex_unlock(&tpg->tv_tpg_mutex);
1674                 pr_err("Unable to allocate struct tcm_vhost_nexus\n");
1675                 return -ENOMEM;
1676         }
1677         /*
1678          *  Initialize the struct se_session pointer
1679          */
1680         tv_nexus->tvn_se_sess = transport_init_session();
1681         if (IS_ERR(tv_nexus->tvn_se_sess)) {
1682                 mutex_unlock(&tpg->tv_tpg_mutex);
1683                 kfree(tv_nexus);
1684                 return -ENOMEM;
1685         }
1686         /*
1687          * Since we are running in 'demo mode' this call with generate a
1688          * struct se_node_acl for the tcm_vhost struct se_portal_group with
1689          * the SCSI Initiator port name of the passed configfs group 'name'.
1690          */
1691         tv_nexus->tvn_se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
1692                                 se_tpg, (unsigned char *)name);
1693         if (!tv_nexus->tvn_se_sess->se_node_acl) {
1694                 mutex_unlock(&tpg->tv_tpg_mutex);
1695                 pr_debug("core_tpg_check_initiator_node_acl() failed"
1696                                 " for %s\n", name);
1697                 transport_free_session(tv_nexus->tvn_se_sess);
1698                 kfree(tv_nexus);
1699                 return -ENOMEM;
1700         }
1701         /*
1702          * Now register the TCM vhost virtual I_T Nexus as active with the
1703          * call to __transport_register_session()
1704          */
1705         __transport_register_session(se_tpg, tv_nexus->tvn_se_sess->se_node_acl,
1706                         tv_nexus->tvn_se_sess, tv_nexus);
1707         tpg->tpg_nexus = tv_nexus;
1708
1709         mutex_unlock(&tpg->tv_tpg_mutex);
1710         return 0;
1711 }
1712
1713 static int tcm_vhost_drop_nexus(struct tcm_vhost_tpg *tpg)
1714 {
1715         struct se_session *se_sess;
1716         struct tcm_vhost_nexus *tv_nexus;
1717
1718         mutex_lock(&tpg->tv_tpg_mutex);
1719         tv_nexus = tpg->tpg_nexus;
1720         if (!tv_nexus) {
1721                 mutex_unlock(&tpg->tv_tpg_mutex);
1722                 return -ENODEV;
1723         }
1724
1725         se_sess = tv_nexus->tvn_se_sess;
1726         if (!se_sess) {
1727                 mutex_unlock(&tpg->tv_tpg_mutex);
1728                 return -ENODEV;
1729         }
1730
1731         if (tpg->tv_tpg_port_count != 0) {
1732                 mutex_unlock(&tpg->tv_tpg_mutex);
1733                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
1734                         " active TPG port count: %d\n",
1735                         tpg->tv_tpg_port_count);
1736                 return -EBUSY;
1737         }
1738
1739         if (tpg->tv_tpg_vhost_count != 0) {
1740                 mutex_unlock(&tpg->tv_tpg_mutex);
1741                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
1742                         " active TPG vhost count: %d\n",
1743                         tpg->tv_tpg_vhost_count);
1744                 return -EBUSY;
1745         }
1746
1747         pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated"
1748                 " %s Initiator Port: %s\n", tcm_vhost_dump_proto_id(tpg->tport),
1749                 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1750         /*
1751          * Release the SCSI I_T Nexus to the emulated vhost Target Port
1752          */
1753         transport_deregister_session(tv_nexus->tvn_se_sess);
1754         tpg->tpg_nexus = NULL;
1755         mutex_unlock(&tpg->tv_tpg_mutex);
1756
1757         kfree(tv_nexus);
1758         return 0;
1759 }
1760
1761 static ssize_t tcm_vhost_tpg_show_nexus(struct se_portal_group *se_tpg,
1762                                         char *page)
1763 {
1764         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1765                                 struct tcm_vhost_tpg, se_tpg);
1766         struct tcm_vhost_nexus *tv_nexus;
1767         ssize_t ret;
1768
1769         mutex_lock(&tpg->tv_tpg_mutex);
1770         tv_nexus = tpg->tpg_nexus;
1771         if (!tv_nexus) {
1772                 mutex_unlock(&tpg->tv_tpg_mutex);
1773                 return -ENODEV;
1774         }
1775         ret = snprintf(page, PAGE_SIZE, "%s\n",
1776                         tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1777         mutex_unlock(&tpg->tv_tpg_mutex);
1778
1779         return ret;
1780 }
1781
1782 static ssize_t tcm_vhost_tpg_store_nexus(struct se_portal_group *se_tpg,
1783                                          const char *page,
1784                                          size_t count)
1785 {
1786         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1787                                 struct tcm_vhost_tpg, se_tpg);
1788         struct tcm_vhost_tport *tport_wwn = tpg->tport;
1789         unsigned char i_port[TCM_VHOST_NAMELEN], *ptr, *port_ptr;
1790         int ret;
1791         /*
1792          * Shutdown the active I_T nexus if 'NULL' is passed..
1793          */
1794         if (!strncmp(page, "NULL", 4)) {
1795                 ret = tcm_vhost_drop_nexus(tpg);
1796                 return (!ret) ? count : ret;
1797         }
1798         /*
1799          * Otherwise make sure the passed virtual Initiator port WWN matches
1800          * the fabric protocol_id set in tcm_vhost_make_tport(), and call
1801          * tcm_vhost_make_nexus().
1802          */
1803         if (strlen(page) >= TCM_VHOST_NAMELEN) {
1804                 pr_err("Emulated NAA Sas Address: %s, exceeds"
1805                                 " max: %d\n", page, TCM_VHOST_NAMELEN);
1806                 return -EINVAL;
1807         }
1808         snprintf(&i_port[0], TCM_VHOST_NAMELEN, "%s", page);
1809
1810         ptr = strstr(i_port, "naa.");
1811         if (ptr) {
1812                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
1813                         pr_err("Passed SAS Initiator Port %s does not"
1814                                 " match target port protoid: %s\n", i_port,
1815                                 tcm_vhost_dump_proto_id(tport_wwn));
1816                         return -EINVAL;
1817                 }
1818                 port_ptr = &i_port[0];
1819                 goto check_newline;
1820         }
1821         ptr = strstr(i_port, "fc.");
1822         if (ptr) {
1823                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
1824                         pr_err("Passed FCP Initiator Port %s does not"
1825                                 " match target port protoid: %s\n", i_port,
1826                                 tcm_vhost_dump_proto_id(tport_wwn));
1827                         return -EINVAL;
1828                 }
1829                 port_ptr = &i_port[3]; /* Skip over "fc." */
1830                 goto check_newline;
1831         }
1832         ptr = strstr(i_port, "iqn.");
1833         if (ptr) {
1834                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
1835                         pr_err("Passed iSCSI Initiator Port %s does not"
1836                                 " match target port protoid: %s\n", i_port,
1837                                 tcm_vhost_dump_proto_id(tport_wwn));
1838                         return -EINVAL;
1839                 }
1840                 port_ptr = &i_port[0];
1841                 goto check_newline;
1842         }
1843         pr_err("Unable to locate prefix for emulated Initiator Port:"
1844                         " %s\n", i_port);
1845         return -EINVAL;
1846         /*
1847          * Clear any trailing newline for the NAA WWN
1848          */
1849 check_newline:
1850         if (i_port[strlen(i_port)-1] == '\n')
1851                 i_port[strlen(i_port)-1] = '\0';
1852
1853         ret = tcm_vhost_make_nexus(tpg, port_ptr);
1854         if (ret < 0)
1855                 return ret;
1856
1857         return count;
1858 }
1859
1860 TF_TPG_BASE_ATTR(tcm_vhost, nexus, S_IRUGO | S_IWUSR);
1861
1862 static struct configfs_attribute *tcm_vhost_tpg_attrs[] = {
1863         &tcm_vhost_tpg_nexus.attr,
1864         NULL,
1865 };
1866
1867 static struct se_portal_group *
1868 tcm_vhost_make_tpg(struct se_wwn *wwn,
1869                    struct config_group *group,
1870                    const char *name)
1871 {
1872         struct tcm_vhost_tport *tport = container_of(wwn,
1873                         struct tcm_vhost_tport, tport_wwn);
1874
1875         struct tcm_vhost_tpg *tpg;
1876         unsigned long tpgt;
1877         int ret;
1878
1879         if (strstr(name, "tpgt_") != name)
1880                 return ERR_PTR(-EINVAL);
1881         if (kstrtoul(name + 5, 10, &tpgt) || tpgt > UINT_MAX)
1882                 return ERR_PTR(-EINVAL);
1883
1884         tpg = kzalloc(sizeof(struct tcm_vhost_tpg), GFP_KERNEL);
1885         if (!tpg) {
1886                 pr_err("Unable to allocate struct tcm_vhost_tpg");
1887                 return ERR_PTR(-ENOMEM);
1888         }
1889         mutex_init(&tpg->tv_tpg_mutex);
1890         INIT_LIST_HEAD(&tpg->tv_tpg_list);
1891         tpg->tport = tport;
1892         tpg->tport_tpgt = tpgt;
1893
1894         ret = core_tpg_register(&tcm_vhost_fabric_configfs->tf_ops, wwn,
1895                                 &tpg->se_tpg, tpg, TRANSPORT_TPG_TYPE_NORMAL);
1896         if (ret < 0) {
1897                 kfree(tpg);
1898                 return NULL;
1899         }
1900         mutex_lock(&tcm_vhost_mutex);
1901         list_add_tail(&tpg->tv_tpg_list, &tcm_vhost_list);
1902         mutex_unlock(&tcm_vhost_mutex);
1903
1904         return &tpg->se_tpg;
1905 }
1906
1907 static void tcm_vhost_drop_tpg(struct se_portal_group *se_tpg)
1908 {
1909         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1910                                 struct tcm_vhost_tpg, se_tpg);
1911
1912         mutex_lock(&tcm_vhost_mutex);
1913         list_del(&tpg->tv_tpg_list);
1914         mutex_unlock(&tcm_vhost_mutex);
1915         /*
1916          * Release the virtual I_T Nexus for this vhost TPG
1917          */
1918         tcm_vhost_drop_nexus(tpg);
1919         /*
1920          * Deregister the se_tpg from TCM..
1921          */
1922         core_tpg_deregister(se_tpg);
1923         kfree(tpg);
1924 }
1925
1926 static struct se_wwn *
1927 tcm_vhost_make_tport(struct target_fabric_configfs *tf,
1928                      struct config_group *group,
1929                      const char *name)
1930 {
1931         struct tcm_vhost_tport *tport;
1932         char *ptr;
1933         u64 wwpn = 0;
1934         int off = 0;
1935
1936         /* if (tcm_vhost_parse_wwn(name, &wwpn, 1) < 0)
1937                 return ERR_PTR(-EINVAL); */
1938
1939         tport = kzalloc(sizeof(struct tcm_vhost_tport), GFP_KERNEL);
1940         if (!tport) {
1941                 pr_err("Unable to allocate struct tcm_vhost_tport");
1942                 return ERR_PTR(-ENOMEM);
1943         }
1944         tport->tport_wwpn = wwpn;
1945         /*
1946          * Determine the emulated Protocol Identifier and Target Port Name
1947          * based on the incoming configfs directory name.
1948          */
1949         ptr = strstr(name, "naa.");
1950         if (ptr) {
1951                 tport->tport_proto_id = SCSI_PROTOCOL_SAS;
1952                 goto check_len;
1953         }
1954         ptr = strstr(name, "fc.");
1955         if (ptr) {
1956                 tport->tport_proto_id = SCSI_PROTOCOL_FCP;
1957                 off = 3; /* Skip over "fc." */
1958                 goto check_len;
1959         }
1960         ptr = strstr(name, "iqn.");
1961         if (ptr) {
1962                 tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
1963                 goto check_len;
1964         }
1965
1966         pr_err("Unable to locate prefix for emulated Target Port:"
1967                         " %s\n", name);
1968         kfree(tport);
1969         return ERR_PTR(-EINVAL);
1970
1971 check_len:
1972         if (strlen(name) >= TCM_VHOST_NAMELEN) {
1973                 pr_err("Emulated %s Address: %s, exceeds"
1974                         " max: %d\n", name, tcm_vhost_dump_proto_id(tport),
1975                         TCM_VHOST_NAMELEN);
1976                 kfree(tport);
1977                 return ERR_PTR(-EINVAL);
1978         }
1979         snprintf(&tport->tport_name[0], TCM_VHOST_NAMELEN, "%s", &name[off]);
1980
1981         pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target"
1982                 " %s Address: %s\n", tcm_vhost_dump_proto_id(tport), name);
1983
1984         return &tport->tport_wwn;
1985 }
1986
1987 static void tcm_vhost_drop_tport(struct se_wwn *wwn)
1988 {
1989         struct tcm_vhost_tport *tport = container_of(wwn,
1990                                 struct tcm_vhost_tport, tport_wwn);
1991
1992         pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target"
1993                 " %s Address: %s\n", tcm_vhost_dump_proto_id(tport),
1994                 tport->tport_name);
1995
1996         kfree(tport);
1997 }
1998
1999 static ssize_t
2000 tcm_vhost_wwn_show_attr_version(struct target_fabric_configfs *tf,
2001                                 char *page)
2002 {
2003         return sprintf(page, "TCM_VHOST fabric module %s on %s/%s"
2004                 "on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname,
2005                 utsname()->machine);
2006 }
2007
2008 TF_WWN_ATTR_RO(tcm_vhost, version);
2009
2010 static struct configfs_attribute *tcm_vhost_wwn_attrs[] = {
2011         &tcm_vhost_wwn_version.attr,
2012         NULL,
2013 };
2014
2015 static struct target_core_fabric_ops tcm_vhost_ops = {
2016         .get_fabric_name                = tcm_vhost_get_fabric_name,
2017         .get_fabric_proto_ident         = tcm_vhost_get_fabric_proto_ident,
2018         .tpg_get_wwn                    = tcm_vhost_get_fabric_wwn,
2019         .tpg_get_tag                    = tcm_vhost_get_tag,
2020         .tpg_get_default_depth          = tcm_vhost_get_default_depth,
2021         .tpg_get_pr_transport_id        = tcm_vhost_get_pr_transport_id,
2022         .tpg_get_pr_transport_id_len    = tcm_vhost_get_pr_transport_id_len,
2023         .tpg_parse_pr_out_transport_id  = tcm_vhost_parse_pr_out_transport_id,
2024         .tpg_check_demo_mode            = tcm_vhost_check_true,
2025         .tpg_check_demo_mode_cache      = tcm_vhost_check_true,
2026         .tpg_check_demo_mode_write_protect = tcm_vhost_check_false,
2027         .tpg_check_prod_mode_write_protect = tcm_vhost_check_false,
2028         .tpg_alloc_fabric_acl           = tcm_vhost_alloc_fabric_acl,
2029         .tpg_release_fabric_acl         = tcm_vhost_release_fabric_acl,
2030         .tpg_get_inst_index             = tcm_vhost_tpg_get_inst_index,
2031         .release_cmd                    = tcm_vhost_release_cmd,
2032         .check_stop_free                = vhost_scsi_check_stop_free,
2033         .shutdown_session               = tcm_vhost_shutdown_session,
2034         .close_session                  = tcm_vhost_close_session,
2035         .sess_get_index                 = tcm_vhost_sess_get_index,
2036         .sess_get_initiator_sid         = NULL,
2037         .write_pending                  = tcm_vhost_write_pending,
2038         .write_pending_status           = tcm_vhost_write_pending_status,
2039         .set_default_node_attributes    = tcm_vhost_set_default_node_attrs,
2040         .get_task_tag                   = tcm_vhost_get_task_tag,
2041         .get_cmd_state                  = tcm_vhost_get_cmd_state,
2042         .queue_data_in                  = tcm_vhost_queue_data_in,
2043         .queue_status                   = tcm_vhost_queue_status,
2044         .queue_tm_rsp                   = tcm_vhost_queue_tm_rsp,
2045         /*
2046          * Setup callers for generic logic in target_core_fabric_configfs.c
2047          */
2048         .fabric_make_wwn                = tcm_vhost_make_tport,
2049         .fabric_drop_wwn                = tcm_vhost_drop_tport,
2050         .fabric_make_tpg                = tcm_vhost_make_tpg,
2051         .fabric_drop_tpg                = tcm_vhost_drop_tpg,
2052         .fabric_post_link               = tcm_vhost_port_link,
2053         .fabric_pre_unlink              = tcm_vhost_port_unlink,
2054         .fabric_make_np                 = NULL,
2055         .fabric_drop_np                 = NULL,
2056         .fabric_make_nodeacl            = tcm_vhost_make_nodeacl,
2057         .fabric_drop_nodeacl            = tcm_vhost_drop_nodeacl,
2058 };
2059
2060 static int tcm_vhost_register_configfs(void)
2061 {
2062         struct target_fabric_configfs *fabric;
2063         int ret;
2064
2065         pr_debug("TCM_VHOST fabric module %s on %s/%s"
2066                 " on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname,
2067                 utsname()->machine);
2068         /*
2069          * Register the top level struct config_item_type with TCM core
2070          */
2071         fabric = target_fabric_configfs_init(THIS_MODULE, "vhost");
2072         if (IS_ERR(fabric)) {
2073                 pr_err("target_fabric_configfs_init() failed\n");
2074                 return PTR_ERR(fabric);
2075         }
2076         /*
2077          * Setup fabric->tf_ops from our local tcm_vhost_ops
2078          */
2079         fabric->tf_ops = tcm_vhost_ops;
2080         /*
2081          * Setup default attribute lists for various fabric->tf_cit_tmpl
2082          */
2083         TF_CIT_TMPL(fabric)->tfc_wwn_cit.ct_attrs = tcm_vhost_wwn_attrs;
2084         TF_CIT_TMPL(fabric)->tfc_tpg_base_cit.ct_attrs = tcm_vhost_tpg_attrs;
2085         TF_CIT_TMPL(fabric)->tfc_tpg_attrib_cit.ct_attrs = NULL;
2086         TF_CIT_TMPL(fabric)->tfc_tpg_param_cit.ct_attrs = NULL;
2087         TF_CIT_TMPL(fabric)->tfc_tpg_np_base_cit.ct_attrs = NULL;
2088         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_base_cit.ct_attrs = NULL;
2089         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_attrib_cit.ct_attrs = NULL;
2090         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_auth_cit.ct_attrs = NULL;
2091         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_param_cit.ct_attrs = NULL;
2092         /*
2093          * Register the fabric for use within TCM
2094          */
2095         ret = target_fabric_configfs_register(fabric);
2096         if (ret < 0) {
2097                 pr_err("target_fabric_configfs_register() failed"
2098                                 " for TCM_VHOST\n");
2099                 return ret;
2100         }
2101         /*
2102          * Setup our local pointer to *fabric
2103          */
2104         tcm_vhost_fabric_configfs = fabric;
2105         pr_debug("TCM_VHOST[0] - Set fabric -> tcm_vhost_fabric_configfs\n");
2106         return 0;
2107 };
2108
2109 static void tcm_vhost_deregister_configfs(void)
2110 {
2111         if (!tcm_vhost_fabric_configfs)
2112                 return;
2113
2114         target_fabric_configfs_deregister(tcm_vhost_fabric_configfs);
2115         tcm_vhost_fabric_configfs = NULL;
2116         pr_debug("TCM_VHOST[0] - Cleared tcm_vhost_fabric_configfs\n");
2117 };
2118
2119 static int __init tcm_vhost_init(void)
2120 {
2121         int ret = -ENOMEM;
2122         /*
2123          * Use our own dedicated workqueue for submitting I/O into
2124          * target core to avoid contention within system_wq.
2125          */
2126         tcm_vhost_workqueue = alloc_workqueue("tcm_vhost", 0, 0);
2127         if (!tcm_vhost_workqueue)
2128                 goto out;
2129
2130         ret = vhost_scsi_register();
2131         if (ret < 0)
2132                 goto out_destroy_workqueue;
2133
2134         ret = tcm_vhost_register_configfs();
2135         if (ret < 0)
2136                 goto out_vhost_scsi_deregister;
2137
2138         return 0;
2139
2140 out_vhost_scsi_deregister:
2141         vhost_scsi_deregister();
2142 out_destroy_workqueue:
2143         destroy_workqueue(tcm_vhost_workqueue);
2144 out:
2145         return ret;
2146 };
2147
2148 static void tcm_vhost_exit(void)
2149 {
2150         tcm_vhost_deregister_configfs();
2151         vhost_scsi_deregister();
2152         destroy_workqueue(tcm_vhost_workqueue);
2153 };
2154
2155 MODULE_DESCRIPTION("VHOST_SCSI series fabric driver");
2156 MODULE_ALIAS("tcm_vhost");
2157 MODULE_LICENSE("GPL");
2158 module_init(tcm_vhost_init);
2159 module_exit(tcm_vhost_exit);