drivers/vhost/scsi.c

   1 /*******************************************************************************
   2  * Vhost kernel TCM fabric driver for virtio SCSI initiators
   3  *
   4  * (C) Copyright 2010-2013 Datera, Inc.
   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@daterainc.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_common.h>
  41 #include <scsi/scsi_proto.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 #include <linux/percpu_ida.h>
  52
  53 #include "vhost.h"
  54
  55 #define VHOST_SCSI_VERSION  "v0.1"
  56 #define VHOST_SCSI_NAMELEN 256
  57 #define VHOST_SCSI_MAX_CDB_SIZE 32
  58 #define VHOST_SCSI_DEFAULT_TAGS 256
  59 #define VHOST_SCSI_PREALLOC_SGLS 2048
  60 #define VHOST_SCSI_PREALLOC_UPAGES 2048
  61 #define VHOST_SCSI_PREALLOC_PROT_SGLS 512
  62
  63 struct vhost_scsi_inflight {
  64         /* Wait for the flush operation to finish */
  65         struct completion comp;
  66         /* Refcount for the inflight reqs */
  67         struct kref kref;
  68 };
  69
  70 struct vhost_scsi_cmd {
  71         /* Descriptor from vhost_get_vq_desc() for virt_queue segment */
  72         int tvc_vq_desc;
  73         /* virtio-scsi initiator task attribute */
  74         int tvc_task_attr;
  75         /* virtio-scsi response incoming iovecs */
  76         int tvc_in_iovs;
  77         /* virtio-scsi initiator data direction */
  78         enum dma_data_direction tvc_data_direction;
  79         /* Expected data transfer length from virtio-scsi header */
  80         u32 tvc_exp_data_len;
  81         /* The Tag from include/linux/virtio_scsi.h:struct virtio_scsi_cmd_req */
  82         u64 tvc_tag;
  83         /* The number of scatterlists associated with this cmd */
  84         u32 tvc_sgl_count;
  85         u32 tvc_prot_sgl_count;
  86         /* Saved unpacked SCSI LUN for vhost_scsi_submission_work() */
  87         u32 tvc_lun;
  88         /* Pointer to the SGL formatted memory from virtio-scsi */
  89         struct scatterlist *tvc_sgl;
  90         struct scatterlist *tvc_prot_sgl;
  91         struct page **tvc_upages;
  92         /* Pointer to response header iovec */
  93         struct iovec *tvc_resp_iov;
  94         /* Pointer to vhost_scsi for our device */
  95         struct vhost_scsi *tvc_vhost;
  96         /* Pointer to vhost_virtqueue for the cmd */
  97         struct vhost_virtqueue *tvc_vq;
  98         /* Pointer to vhost nexus memory */
  99         struct vhost_scsi_nexus *tvc_nexus;
 100         /* The TCM I/O descriptor that is accessed via container_of() */
 101         struct se_cmd tvc_se_cmd;
 102         /* work item used for cmwq dispatch to vhost_scsi_submission_work() */
 103         struct work_struct work;
 104         /* Copy of the incoming SCSI command descriptor block (CDB) */
 105         unsigned char tvc_cdb[VHOST_SCSI_MAX_CDB_SIZE];
 106         /* Sense buffer that will be mapped into outgoing status */
 107         unsigned char tvc_sense_buf[TRANSPORT_SENSE_BUFFER];
 108         /* Completed commands list, serviced from vhost worker thread */
 109         struct llist_node tvc_completion_list;
 110         /* Used to track inflight cmd */
 111         struct vhost_scsi_inflight *inflight;
 112 };
 113
 114 struct vhost_scsi_nexus {
 115         /* Pointer to TCM session for I_T Nexus */
 116         struct se_session *tvn_se_sess;
 117 };
 118
 119 struct vhost_scsi_nacl {
 120         /* Binary World Wide unique Port Name for Vhost Initiator port */
 121         u64 iport_wwpn;
 122         /* ASCII formatted WWPN for Sas Initiator port */
 123         char iport_name[VHOST_SCSI_NAMELEN];
 124         /* Returned by vhost_scsi_make_nodeacl() */
 125         struct se_node_acl se_node_acl;
 126 };
 127
 128 struct vhost_scsi_tpg {
 129         /* Vhost port target portal group tag for TCM */
 130         u16 tport_tpgt;
 131         /* Used to track number of TPG Port/Lun Links wrt to explict I_T Nexus shutdown */
 132         int tv_tpg_port_count;
 133         /* Used for vhost_scsi device reference to tpg_nexus, protected by tv_tpg_mutex */
 134         int tv_tpg_vhost_count;
 135         /* Used for enabling T10-PI with legacy devices */
 136         int tv_fabric_prot_type;
 137         /* list for vhost_scsi_list */
 138         struct list_head tv_tpg_list;
 139         /* Used to protect access for tpg_nexus */
 140         struct mutex tv_tpg_mutex;
 141         /* Pointer to the TCM VHost I_T Nexus for this TPG endpoint */
 142         struct vhost_scsi_nexus *tpg_nexus;
 143         /* Pointer back to vhost_scsi_tport */
 144         struct vhost_scsi_tport *tport;
 145         /* Returned by vhost_scsi_make_tpg() */
 146         struct se_portal_group se_tpg;
 147         /* Pointer back to vhost_scsi, protected by tv_tpg_mutex */
 148         struct vhost_scsi *vhost_scsi;
 149 };
 150
 151 struct vhost_scsi_tport {
 152         /* SCSI protocol the tport is providing */
 153         u8 tport_proto_id;
 154         /* Binary World Wide unique Port Name for Vhost Target port */
 155         u64 tport_wwpn;
 156         /* ASCII formatted WWPN for Vhost Target port */
 157         char tport_name[VHOST_SCSI_NAMELEN];
 158         /* Returned by vhost_scsi_make_tport() */
 159         struct se_wwn tport_wwn;
 160 };
 161
 162 struct vhost_scsi_evt {
 163         /* event to be sent to guest */
 164         struct virtio_scsi_event event;
 165         /* event list, serviced from vhost worker thread */
 166         struct llist_node list;
 167 };
 168
 169 enum {
 170         VHOST_SCSI_VQ_CTL = 0,
 171         VHOST_SCSI_VQ_EVT = 1,
 172         VHOST_SCSI_VQ_IO = 2,
 173 };
 174
 175 /* Note: can't set VIRTIO_F_VERSION_1 yet, since that implies ANY_LAYOUT. */
 176 enum {
 177         VHOST_SCSI_FEATURES = VHOST_FEATURES | (1ULL << VIRTIO_SCSI_F_HOTPLUG) |
 178                                                (1ULL << VIRTIO_SCSI_F_T10_PI) |
 179                                                (1ULL << VIRTIO_F_ANY_LAYOUT) |
 180                                                (1ULL << VIRTIO_F_VERSION_1)
 181 };
 182
 183 #define VHOST_SCSI_MAX_TARGET   256
 184 #define VHOST_SCSI_MAX_VQ       128
 185 #define VHOST_SCSI_MAX_EVENT    128
 186
 187 struct vhost_scsi_virtqueue {
 188         struct vhost_virtqueue vq;
 189         /*
 190          * Reference counting for inflight reqs, used for flush operation. At
 191          * each time, one reference tracks new commands submitted, while we
 192          * wait for another one to reach 0.
 193          */
 194         struct vhost_scsi_inflight inflights[2];
 195         /*
 196          * Indicate current inflight in use, protected by vq->mutex.
 197          * Writers must also take dev mutex and flush under it.
 198          */
 199         int inflight_idx;
 200 };
 201
 202 struct vhost_scsi {
 203         /* Protected by vhost_scsi->dev.mutex */
 204         struct vhost_scsi_tpg **vs_tpg;
 205         char vs_vhost_wwpn[TRANSPORT_IQN_LEN];
 206
 207         struct vhost_dev dev;
 208         struct vhost_scsi_virtqueue vqs[VHOST_SCSI_MAX_VQ];
 209
 210         struct vhost_work vs_completion_work; /* cmd completion work item */
 211         struct llist_head vs_completion_list; /* cmd completion queue */
 212
 213         struct vhost_work vs_event_work; /* evt injection work item */
 214         struct llist_head vs_event_list; /* evt injection queue */
 215
 216         bool vs_events_missed; /* any missed events, protected by vq->mutex */
 217         int vs_events_nr; /* num of pending events, protected by vq->mutex */
 218 };
 219
 220 static struct target_core_fabric_ops vhost_scsi_ops;
 221 static struct workqueue_struct *vhost_scsi_workqueue;
 222
 223 /* Global spinlock to protect vhost_scsi TPG list for vhost IOCTL access */
 224 static DEFINE_MUTEX(vhost_scsi_mutex);
 225 static LIST_HEAD(vhost_scsi_list);
 226
 227 static int iov_num_pages(void __user *iov_base, size_t iov_len)
 228 {
 229         return (PAGE_ALIGN((unsigned long)iov_base + iov_len) -
 230                ((unsigned long)iov_base & PAGE_MASK)) >> PAGE_SHIFT;
 231 }
 232
 233 static void vhost_scsi_done_inflight(struct kref *kref)
 234 {
 235         struct vhost_scsi_inflight *inflight;
 236
 237         inflight = container_of(kref, struct vhost_scsi_inflight, kref);
 238         complete(&inflight->comp);
 239 }
 240
 241 static void vhost_scsi_init_inflight(struct vhost_scsi *vs,
 242                                     struct vhost_scsi_inflight *old_inflight[])
 243 {
 244         struct vhost_scsi_inflight *new_inflight;
 245         struct vhost_virtqueue *vq;
 246         int idx, i;
 247
 248         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
 249                 vq = &vs->vqs[i].vq;
 250
 251                 mutex_lock(&vq->mutex);
 252
 253                 /* store old infight */
 254                 idx = vs->vqs[i].inflight_idx;
 255                 if (old_inflight)
 256                         old_inflight[i] = &vs->vqs[i].inflights[idx];
 257
 258                 /* setup new infight */
 259                 vs->vqs[i].inflight_idx = idx ^ 1;
 260                 new_inflight = &vs->vqs[i].inflights[idx ^ 1];
 261                 kref_init(&new_inflight->kref);
 262                 init_completion(&new_inflight->comp);
 263
 264                 mutex_unlock(&vq->mutex);
 265         }
 266 }
 267
 268 static struct vhost_scsi_inflight *
 269 vhost_scsi_get_inflight(struct vhost_virtqueue *vq)
 270 {
 271         struct vhost_scsi_inflight *inflight;
 272         struct vhost_scsi_virtqueue *svq;
 273
 274         svq = container_of(vq, struct vhost_scsi_virtqueue, vq);
 275         inflight = &svq->inflights[svq->inflight_idx];
 276         kref_get(&inflight->kref);
 277
 278         return inflight;
 279 }
 280
 281 static void vhost_scsi_put_inflight(struct vhost_scsi_inflight *inflight)
 282 {
 283         kref_put(&inflight->kref, vhost_scsi_done_inflight);
 284 }
 285
 286 static int vhost_scsi_check_true(struct se_portal_group *se_tpg)
 287 {
 288         return 1;
 289 }
 290
 291 static int vhost_scsi_check_false(struct se_portal_group *se_tpg)
 292 {
 293         return 0;
 294 }
 295
 296 static char *vhost_scsi_get_fabric_name(void)
 297 {
 298         return "vhost";
 299 }
 300
 301 static u8 vhost_scsi_get_fabric_proto_ident(struct se_portal_group *se_tpg)
 302 {
 303         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 304                                 struct vhost_scsi_tpg, se_tpg);
 305         struct vhost_scsi_tport *tport = tpg->tport;
 306
 307         switch (tport->tport_proto_id) {
 308         case SCSI_PROTOCOL_SAS:
 309                 return sas_get_fabric_proto_ident(se_tpg);
 310         case SCSI_PROTOCOL_FCP:
 311                 return fc_get_fabric_proto_ident(se_tpg);
 312         case SCSI_PROTOCOL_ISCSI:
 313                 return iscsi_get_fabric_proto_ident(se_tpg);
 314         default:
 315                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 316                         " SAS emulation\n", tport->tport_proto_id);
 317                 break;
 318         }
 319
 320         return sas_get_fabric_proto_ident(se_tpg);
 321 }
 322
 323 static char *vhost_scsi_get_fabric_wwn(struct se_portal_group *se_tpg)
 324 {
 325         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 326                                 struct vhost_scsi_tpg, se_tpg);
 327         struct vhost_scsi_tport *tport = tpg->tport;
 328
 329         return &tport->tport_name[0];
 330 }
 331
 332 static u16 vhost_scsi_get_tpgt(struct se_portal_group *se_tpg)
 333 {
 334         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 335                                 struct vhost_scsi_tpg, se_tpg);
 336         return tpg->tport_tpgt;
 337 }
 338
 339 static u32 vhost_scsi_get_default_depth(struct se_portal_group *se_tpg)
 340 {
 341         return 1;
 342 }
 343
 344 static u32
 345 vhost_scsi_get_pr_transport_id(struct se_portal_group *se_tpg,
 346                               struct se_node_acl *se_nacl,
 347                               struct t10_pr_registration *pr_reg,
 348                               int *format_code,
 349                               unsigned char *buf)
 350 {
 351         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 352                                 struct vhost_scsi_tpg, se_tpg);
 353         struct vhost_scsi_tport *tport = tpg->tport;
 354
 355         switch (tport->tport_proto_id) {
 356         case SCSI_PROTOCOL_SAS:
 357                 return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 358                                         format_code, buf);
 359         case SCSI_PROTOCOL_FCP:
 360                 return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 361                                         format_code, buf);
 362         case SCSI_PROTOCOL_ISCSI:
 363                 return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 364                                         format_code, buf);
 365         default:
 366                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 367                         " SAS emulation\n", tport->tport_proto_id);
 368                 break;
 369         }
 370
 371         return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 372                         format_code, buf);
 373 }
 374
 375 static u32
 376 vhost_scsi_get_pr_transport_id_len(struct se_portal_group *se_tpg,
 377                                   struct se_node_acl *se_nacl,
 378                                   struct t10_pr_registration *pr_reg,
 379                                   int *format_code)
 380 {
 381         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 382                                 struct vhost_scsi_tpg, se_tpg);
 383         struct vhost_scsi_tport *tport = tpg->tport;
 384
 385         switch (tport->tport_proto_id) {
 386         case SCSI_PROTOCOL_SAS:
 387                 return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 388                                         format_code);
 389         case SCSI_PROTOCOL_FCP:
 390                 return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 391                                         format_code);
 392         case SCSI_PROTOCOL_ISCSI:
 393                 return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 394                                         format_code);
 395         default:
 396                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 397                         " SAS emulation\n", tport->tport_proto_id);
 398                 break;
 399         }
 400
 401         return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 402                         format_code);
 403 }
 404
 405 static char *
 406 vhost_scsi_parse_pr_out_transport_id(struct se_portal_group *se_tpg,
 407                                     const char *buf,
 408                                     u32 *out_tid_len,
 409                                     char **port_nexus_ptr)
 410 {
 411         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 412                                 struct vhost_scsi_tpg, se_tpg);
 413         struct vhost_scsi_tport *tport = tpg->tport;
 414
 415         switch (tport->tport_proto_id) {
 416         case SCSI_PROTOCOL_SAS:
 417                 return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 418                                         port_nexus_ptr);
 419         case SCSI_PROTOCOL_FCP:
 420                 return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 421                                         port_nexus_ptr);
 422         case SCSI_PROTOCOL_ISCSI:
 423                 return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 424                                         port_nexus_ptr);
 425         default:
 426                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 427                         " SAS emulation\n", tport->tport_proto_id);
 428                 break;
 429         }
 430
 431         return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 432                         port_nexus_ptr);
 433 }
 434
 435 static int vhost_scsi_check_prot_fabric_only(struct se_portal_group *se_tpg)
 436 {
 437         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 438                                 struct vhost_scsi_tpg, se_tpg);
 439
 440         return tpg->tv_fabric_prot_type;
 441 }
 442
 443 static struct se_node_acl *
 444 vhost_scsi_alloc_fabric_acl(struct se_portal_group *se_tpg)
 445 {
 446         struct vhost_scsi_nacl *nacl;
 447
 448         nacl = kzalloc(sizeof(struct vhost_scsi_nacl), GFP_KERNEL);
 449         if (!nacl) {
 450                 pr_err("Unable to allocate struct vhost_scsi_nacl\n");
 451                 return NULL;
 452         }
 453
 454         return &nacl->se_node_acl;
 455 }
 456
 457 static void
 458 vhost_scsi_release_fabric_acl(struct se_portal_group *se_tpg,
 459                              struct se_node_acl *se_nacl)
 460 {
 461         struct vhost_scsi_nacl *nacl = container_of(se_nacl,
 462                         struct vhost_scsi_nacl, se_node_acl);
 463         kfree(nacl);
 464 }
 465
 466 static u32 vhost_scsi_tpg_get_inst_index(struct se_portal_group *se_tpg)
 467 {
 468         return 1;
 469 }
 470
 471 static void vhost_scsi_release_cmd(struct se_cmd *se_cmd)
 472 {
 473         struct vhost_scsi_cmd *tv_cmd = container_of(se_cmd,
 474                                 struct vhost_scsi_cmd, tvc_se_cmd);
 475         struct se_session *se_sess = tv_cmd->tvc_nexus->tvn_se_sess;
 476         int i;
 477
 478         if (tv_cmd->tvc_sgl_count) {
 479                 for (i = 0; i < tv_cmd->tvc_sgl_count; i++)
 480                         put_page(sg_page(&tv_cmd->tvc_sgl[i]));
 481         }
 482         if (tv_cmd->tvc_prot_sgl_count) {
 483                 for (i = 0; i < tv_cmd->tvc_prot_sgl_count; i++)
 484                         put_page(sg_page(&tv_cmd->tvc_prot_sgl[i]));
 485         }
 486
 487         vhost_scsi_put_inflight(tv_cmd->inflight);
 488         percpu_ida_free(&se_sess->sess_tag_pool, se_cmd->map_tag);
 489 }
 490
 491 static int vhost_scsi_shutdown_session(struct se_session *se_sess)
 492 {
 493         return 0;
 494 }
 495
 496 static void vhost_scsi_close_session(struct se_session *se_sess)
 497 {
 498         return;
 499 }
 500
 501 static u32 vhost_scsi_sess_get_index(struct se_session *se_sess)
 502 {
 503         return 0;
 504 }
 505
 506 static int vhost_scsi_write_pending(struct se_cmd *se_cmd)
 507 {
 508         /* Go ahead and process the write immediately */
 509         target_execute_cmd(se_cmd);
 510         return 0;
 511 }
 512
 513 static int vhost_scsi_write_pending_status(struct se_cmd *se_cmd)
 514 {
 515         return 0;
 516 }
 517
 518 static void vhost_scsi_set_default_node_attrs(struct se_node_acl *nacl)
 519 {
 520         return;
 521 }
 522
 523 static u32 vhost_scsi_get_task_tag(struct se_cmd *se_cmd)
 524 {
 525         return 0;
 526 }
 527
 528 static int vhost_scsi_get_cmd_state(struct se_cmd *se_cmd)
 529 {
 530         return 0;
 531 }
 532
 533 static void vhost_scsi_complete_cmd(struct vhost_scsi_cmd *cmd)
 534 {
 535         struct vhost_scsi *vs = cmd->tvc_vhost;
 536
 537         llist_add(&cmd->tvc_completion_list, &vs->vs_completion_list);
 538
 539         vhost_work_queue(&vs->dev, &vs->vs_completion_work);
 540 }
 541
 542 static int vhost_scsi_queue_data_in(struct se_cmd *se_cmd)
 543 {
 544         struct vhost_scsi_cmd *cmd = container_of(se_cmd,
 545                                 struct vhost_scsi_cmd, tvc_se_cmd);
 546         vhost_scsi_complete_cmd(cmd);
 547         return 0;
 548 }
 549
 550 static int vhost_scsi_queue_status(struct se_cmd *se_cmd)
 551 {
 552         struct vhost_scsi_cmd *cmd = container_of(se_cmd,
 553                                 struct vhost_scsi_cmd, tvc_se_cmd);
 554         vhost_scsi_complete_cmd(cmd);
 555         return 0;
 556 }
 557
 558 static void vhost_scsi_queue_tm_rsp(struct se_cmd *se_cmd)
 559 {
 560         return;
 561 }
 562
 563 static void vhost_scsi_aborted_task(struct se_cmd *se_cmd)
 564 {
 565         return;
 566 }
 567
 568 static void vhost_scsi_free_evt(struct vhost_scsi *vs, struct vhost_scsi_evt *evt)
 569 {
 570         vs->vs_events_nr--;
 571         kfree(evt);
 572 }
 573
 574 static struct vhost_scsi_evt *
 575 vhost_scsi_allocate_evt(struct vhost_scsi *vs,
 576                        u32 event, u32 reason)
 577 {
 578         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 579         struct vhost_scsi_evt *evt;
 580
 581         if (vs->vs_events_nr > VHOST_SCSI_MAX_EVENT) {
 582                 vs->vs_events_missed = true;
 583                 return NULL;
 584         }
 585
 586         evt = kzalloc(sizeof(*evt), GFP_KERNEL);
 587         if (!evt) {
 588                 vq_err(vq, "Failed to allocate vhost_scsi_evt\n");
 589                 vs->vs_events_missed = true;
 590                 return NULL;
 591         }
 592
 593         evt->event.event = cpu_to_vhost32(vq, event);
 594         evt->event.reason = cpu_to_vhost32(vq, reason);
 595         vs->vs_events_nr++;
 596
 597         return evt;
 598 }
 599
 600 static void vhost_scsi_free_cmd(struct vhost_scsi_cmd *cmd)
 601 {
 602         struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
 603
 604         /* TODO locking against target/backend threads? */
 605         transport_generic_free_cmd(se_cmd, 0);
 606
 607 }
 608
 609 static int vhost_scsi_check_stop_free(struct se_cmd *se_cmd)
 610 {
 611         return target_put_sess_cmd(se_cmd->se_sess, se_cmd);
 612 }
 613
 614 static void
 615 vhost_scsi_do_evt_work(struct vhost_scsi *vs, struct vhost_scsi_evt *evt)
 616 {
 617         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 618         struct virtio_scsi_event *event = &evt->event;
 619         struct virtio_scsi_event __user *eventp;
 620         unsigned out, in;
 621         int head, ret;
 622
 623         if (!vq->private_data) {
 624                 vs->vs_events_missed = true;
 625                 return;
 626         }
 627
 628 again:
 629         vhost_disable_notify(&vs->dev, vq);
 630         head = vhost_get_vq_desc(vq, vq->iov,
 631                         ARRAY_SIZE(vq->iov), &out, &in,
 632                         NULL, NULL);
 633         if (head < 0) {
 634                 vs->vs_events_missed = true;
 635                 return;
 636         }
 637         if (head == vq->num) {
 638                 if (vhost_enable_notify(&vs->dev, vq))
 639                         goto again;
 640                 vs->vs_events_missed = true;
 641                 return;
 642         }
 643
 644         if ((vq->iov[out].iov_len != sizeof(struct virtio_scsi_event))) {
 645                 vq_err(vq, "Expecting virtio_scsi_event, got %zu bytes\n",
 646                                 vq->iov[out].iov_len);
 647                 vs->vs_events_missed = true;
 648                 return;
 649         }
 650
 651         if (vs->vs_events_missed) {
 652                 event->event |= cpu_to_vhost32(vq, VIRTIO_SCSI_T_EVENTS_MISSED);
 653                 vs->vs_events_missed = false;
 654         }
 655
 656         eventp = vq->iov[out].iov_base;
 657         ret = __copy_to_user(eventp, event, sizeof(*event));
 658         if (!ret)
 659                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 660         else
 661                 vq_err(vq, "Faulted on vhost_scsi_send_event\n");
 662 }
 663
 664 static void vhost_scsi_evt_work(struct vhost_work *work)
 665 {
 666         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 667                                         vs_event_work);
 668         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 669         struct vhost_scsi_evt *evt;
 670         struct llist_node *llnode;
 671
 672         mutex_lock(&vq->mutex);
 673         llnode = llist_del_all(&vs->vs_event_list);
 674         while (llnode) {
 675                 evt = llist_entry(llnode, struct vhost_scsi_evt, list);
 676                 llnode = llist_next(llnode);
 677                 vhost_scsi_do_evt_work(vs, evt);
 678                 vhost_scsi_free_evt(vs, evt);
 679         }
 680         mutex_unlock(&vq->mutex);
 681 }
 682
 683 /* Fill in status and signal that we are done processing this command
 684  *
 685  * This is scheduled in the vhost work queue so we are called with the owner
 686  * process mm and can access the vring.
 687  */
 688 static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
 689 {
 690         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 691                                         vs_completion_work);
 692         DECLARE_BITMAP(signal, VHOST_SCSI_MAX_VQ);
 693         struct virtio_scsi_cmd_resp v_rsp;
 694         struct vhost_scsi_cmd *cmd;
 695         struct llist_node *llnode;
 696         struct se_cmd *se_cmd;
 697         struct iov_iter iov_iter;
 698         int ret, vq;
 699
 700         bitmap_zero(signal, VHOST_SCSI_MAX_VQ);
 701         llnode = llist_del_all(&vs->vs_completion_list);
 702         while (llnode) {
 703                 cmd = llist_entry(llnode, struct vhost_scsi_cmd,
 704                                      tvc_completion_list);
 705                 llnode = llist_next(llnode);
 706                 se_cmd = &cmd->tvc_se_cmd;
 707
 708                 pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__,
 709                         cmd, se_cmd->residual_count, se_cmd->scsi_status);
 710
 711                 memset(&v_rsp, 0, sizeof(v_rsp));
 712                 v_rsp.resid = cpu_to_vhost32(cmd->tvc_vq, se_cmd->residual_count);
 713                 /* TODO is status_qualifier field needed? */
 714                 v_rsp.status = se_cmd->scsi_status;
 715                 v_rsp.sense_len = cpu_to_vhost32(cmd->tvc_vq,
 716                                                  se_cmd->scsi_sense_length);
 717                 memcpy(v_rsp.sense, cmd->tvc_sense_buf,
 718                        se_cmd->scsi_sense_length);
 719
 720                 iov_iter_init(&iov_iter, READ, cmd->tvc_resp_iov,
 721                               cmd->tvc_in_iovs, sizeof(v_rsp));
 722                 ret = copy_to_iter(&v_rsp, sizeof(v_rsp), &iov_iter);
 723                 if (likely(ret == sizeof(v_rsp))) {
 724                         struct vhost_scsi_virtqueue *q;
 725                         vhost_add_used(cmd->tvc_vq, cmd->tvc_vq_desc, 0);
 726                         q = container_of(cmd->tvc_vq, struct vhost_scsi_virtqueue, vq);
 727                         vq = q - vs->vqs;
 728                         __set_bit(vq, signal);
 729                 } else
 730                         pr_err("Faulted on virtio_scsi_cmd_resp\n");
 731
 732                 vhost_scsi_free_cmd(cmd);
 733         }
 734
 735         vq = -1;
 736         while ((vq = find_next_bit(signal, VHOST_SCSI_MAX_VQ, vq + 1))
 737                 < VHOST_SCSI_MAX_VQ)
 738                 vhost_signal(&vs->dev, &vs->vqs[vq].vq);
 739 }
 740
 741 static struct vhost_scsi_cmd *
 742 vhost_scsi_get_tag(struct vhost_virtqueue *vq, struct vhost_scsi_tpg *tpg,
 743                    unsigned char *cdb, u64 scsi_tag, u16 lun, u8 task_attr,
 744                    u32 exp_data_len, int data_direction)
 745 {
 746         struct vhost_scsi_cmd *cmd;
 747         struct vhost_scsi_nexus *tv_nexus;
 748         struct se_session *se_sess;
 749         struct scatterlist *sg, *prot_sg;
 750         struct page **pages;
 751         int tag;
 752
 753         tv_nexus = tpg->tpg_nexus;
 754         if (!tv_nexus) {
 755                 pr_err("Unable to locate active struct vhost_scsi_nexus\n");
 756                 return ERR_PTR(-EIO);
 757         }
 758         se_sess = tv_nexus->tvn_se_sess;
 759
 760         tag = percpu_ida_alloc(&se_sess->sess_tag_pool, TASK_RUNNING);
 761         if (tag < 0) {
 762                 pr_err("Unable to obtain tag for vhost_scsi_cmd\n");
 763                 return ERR_PTR(-ENOMEM);
 764         }
 765
 766         cmd = &((struct vhost_scsi_cmd *)se_sess->sess_cmd_map)[tag];
 767         sg = cmd->tvc_sgl;
 768         prot_sg = cmd->tvc_prot_sgl;
 769         pages = cmd->tvc_upages;
 770         memset(cmd, 0, sizeof(struct vhost_scsi_cmd));
 771
 772         cmd->tvc_sgl = sg;
 773         cmd->tvc_prot_sgl = prot_sg;
 774         cmd->tvc_upages = pages;
 775         cmd->tvc_se_cmd.map_tag = tag;
 776         cmd->tvc_tag = scsi_tag;
 777         cmd->tvc_lun = lun;
 778         cmd->tvc_task_attr = task_attr;
 779         cmd->tvc_exp_data_len = exp_data_len;
 780         cmd->tvc_data_direction = data_direction;
 781         cmd->tvc_nexus = tv_nexus;
 782         cmd->inflight = vhost_scsi_get_inflight(vq);
 783
 784         memcpy(cmd->tvc_cdb, cdb, VHOST_SCSI_MAX_CDB_SIZE);
 785
 786         return cmd;
 787 }
 788
 789 /*
 790  * Map a user memory range into a scatterlist
 791  *
 792  * Returns the number of scatterlist entries used or -errno on error.
 793  */
 794 static int
 795 vhost_scsi_map_to_sgl(struct vhost_scsi_cmd *cmd,
 796                       void __user *ptr,
 797                       size_t len,
 798                       struct scatterlist *sgl,
 799                       bool write)
 800 {
 801         unsigned int npages = 0, offset, nbytes;
 802         unsigned int pages_nr = iov_num_pages(ptr, len);
 803         struct scatterlist *sg = sgl;
 804         struct page **pages = cmd->tvc_upages;
 805         int ret, i;
 806
 807         if (pages_nr > VHOST_SCSI_PREALLOC_UPAGES) {
 808                 pr_err("vhost_scsi_map_to_sgl() pages_nr: %u greater than"
 809                        " preallocated VHOST_SCSI_PREALLOC_UPAGES: %u\n",
 810                         pages_nr, VHOST_SCSI_PREALLOC_UPAGES);
 811                 return -ENOBUFS;
 812         }
 813
 814         ret = get_user_pages_fast((unsigned long)ptr, pages_nr, write, pages);
 815         /* No pages were pinned */
 816         if (ret < 0)
 817                 goto out;
 818         /* Less pages pinned than wanted */
 819         if (ret != pages_nr) {
 820                 for (i = 0; i < ret; i++)
 821                         put_page(pages[i]);
 822                 ret = -EFAULT;
 823                 goto out;
 824         }
 825
 826         while (len > 0) {
 827                 offset = (uintptr_t)ptr & ~PAGE_MASK;
 828                 nbytes = min_t(unsigned int, PAGE_SIZE - offset, len);
 829                 sg_set_page(sg, pages[npages], nbytes, offset);
 830                 ptr += nbytes;
 831                 len -= nbytes;
 832                 sg++;
 833                 npages++;
 834         }
 835
 836 out:
 837         return ret;
 838 }
 839
 840 static int
 841 vhost_scsi_calc_sgls(struct iov_iter *iter, size_t bytes, int max_sgls)
 842 {
 843         int sgl_count = 0;
 844
 845         if (!iter || !iter->iov) {
 846                 pr_err("%s: iter->iov is NULL, but expected bytes: %zu"
 847                        " present\n", __func__, bytes);
 848                 return -EINVAL;
 849         }
 850
 851         sgl_count = iov_iter_npages(iter, 0xffff);
 852         if (sgl_count > max_sgls) {
 853                 pr_err("%s: requested sgl_count: %d exceeds pre-allocated"
 854                        " max_sgls: %d\n", __func__, sgl_count, max_sgls);
 855                 return -EINVAL;
 856         }
 857         return sgl_count;
 858 }
 859
 860 static int
 861 vhost_scsi_iov_to_sgl(struct vhost_scsi_cmd *cmd, bool write,
 862                       struct iov_iter *iter,
 863                       struct scatterlist *sg, int sg_count)
 864 {
 865         size_t off = iter->iov_offset;
 866         int i, ret;
 867
 868         for (i = 0; i < iter->nr_segs; i++) {
 869                 void __user *base = iter->iov[i].iov_base + off;
 870                 size_t len = iter->iov[i].iov_len - off;
 871
 872                 ret = vhost_scsi_map_to_sgl(cmd, base, len, sg, write);
 873                 if (ret < 0) {
 874                         for (i = 0; i < sg_count; i++) {
 875                                 struct page *page = sg_page(&sg[i]);
 876                                 if (page)
 877                                         put_page(page);
 878                         }
 879                         return ret;
 880                 }
 881                 sg += ret;
 882                 off = 0;
 883         }
 884         return 0;
 885 }
 886
 887 static int
 888 vhost_scsi_mapal(struct vhost_scsi_cmd *cmd,
 889                  size_t prot_bytes, struct iov_iter *prot_iter,
 890                  size_t data_bytes, struct iov_iter *data_iter)
 891 {
 892         int sgl_count, ret;
 893         bool write = (cmd->tvc_data_direction == DMA_FROM_DEVICE);
 894
 895         if (prot_bytes) {
 896                 sgl_count = vhost_scsi_calc_sgls(prot_iter, prot_bytes,
 897                                                  VHOST_SCSI_PREALLOC_PROT_SGLS);
 898                 if (sgl_count < 0)
 899                         return sgl_count;
 900
 901                 sg_init_table(cmd->tvc_prot_sgl, sgl_count);
 902                 cmd->tvc_prot_sgl_count = sgl_count;
 903                 pr_debug("%s prot_sg %p prot_sgl_count %u\n", __func__,
 904                          cmd->tvc_prot_sgl, cmd->tvc_prot_sgl_count);
 905
 906                 ret = vhost_scsi_iov_to_sgl(cmd, write, prot_iter,
 907                                             cmd->tvc_prot_sgl,
 908                                             cmd->tvc_prot_sgl_count);
 909                 if (ret < 0) {
 910                         cmd->tvc_prot_sgl_count = 0;
 911                         return ret;
 912                 }
 913         }
 914         sgl_count = vhost_scsi_calc_sgls(data_iter, data_bytes,
 915                                          VHOST_SCSI_PREALLOC_SGLS);
 916         if (sgl_count < 0)
 917                 return sgl_count;
 918
 919         sg_init_table(cmd->tvc_sgl, sgl_count);
 920         cmd->tvc_sgl_count = sgl_count;
 921         pr_debug("%s data_sg %p data_sgl_count %u\n", __func__,
 922                   cmd->tvc_sgl, cmd->tvc_sgl_count);
 923
 924         ret = vhost_scsi_iov_to_sgl(cmd, write, data_iter,
 925                                     cmd->tvc_sgl, cmd->tvc_sgl_count);
 926         if (ret < 0) {
 927                 cmd->tvc_sgl_count = 0;
 928                 return ret;
 929         }
 930         return 0;
 931 }
 932
 933 static int vhost_scsi_to_tcm_attr(int attr)
 934 {
 935         switch (attr) {
 936         case VIRTIO_SCSI_S_SIMPLE:
 937                 return TCM_SIMPLE_TAG;
 938         case VIRTIO_SCSI_S_ORDERED:
 939                 return TCM_ORDERED_TAG;
 940         case VIRTIO_SCSI_S_HEAD:
 941                 return TCM_HEAD_TAG;
 942         case VIRTIO_SCSI_S_ACA:
 943                 return TCM_ACA_TAG;
 944         default:
 945                 break;
 946         }
 947         return TCM_SIMPLE_TAG;
 948 }
 949
 950 static void vhost_scsi_submission_work(struct work_struct *work)
 951 {
 952         struct vhost_scsi_cmd *cmd =
 953                 container_of(work, struct vhost_scsi_cmd, work);
 954         struct vhost_scsi_nexus *tv_nexus;
 955         struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
 956         struct scatterlist *sg_ptr, *sg_prot_ptr = NULL;
 957         int rc;
 958
 959         /* FIXME: BIDI operation */
 960         if (cmd->tvc_sgl_count) {
 961                 sg_ptr = cmd->tvc_sgl;
 962
 963                 if (cmd->tvc_prot_sgl_count)
 964                         sg_prot_ptr = cmd->tvc_prot_sgl;
 965                 else
 966                         se_cmd->prot_pto = true;
 967         } else {
 968                 sg_ptr = NULL;
 969         }
 970         tv_nexus = cmd->tvc_nexus;
 971
 972         rc = target_submit_cmd_map_sgls(se_cmd, tv_nexus->tvn_se_sess,
 973                         cmd->tvc_cdb, &cmd->tvc_sense_buf[0],
 974                         cmd->tvc_lun, cmd->tvc_exp_data_len,
 975                         vhost_scsi_to_tcm_attr(cmd->tvc_task_attr),
 976                         cmd->tvc_data_direction, TARGET_SCF_ACK_KREF,
 977                         sg_ptr, cmd->tvc_sgl_count, NULL, 0, sg_prot_ptr,
 978                         cmd->tvc_prot_sgl_count);
 979         if (rc < 0) {
 980                 transport_send_check_condition_and_sense(se_cmd,
 981                                 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
 982                 transport_generic_free_cmd(se_cmd, 0);
 983         }
 984 }
 985
 986 static void
 987 vhost_scsi_send_bad_target(struct vhost_scsi *vs,
 988                            struct vhost_virtqueue *vq,
 989                            int head, unsigned out)
 990 {
 991         struct virtio_scsi_cmd_resp __user *resp;
 992         struct virtio_scsi_cmd_resp rsp;
 993         int ret;
 994
 995         memset(&rsp, 0, sizeof(rsp));
 996         rsp.response = VIRTIO_SCSI_S_BAD_TARGET;
 997         resp = vq->iov[out].iov_base;
 998         ret = __copy_to_user(resp, &rsp, sizeof(rsp));
 999         if (!ret)
1000                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
1001         else
1002                 pr_err("Faulted on virtio_scsi_cmd_resp\n");
1003 }
1004
1005 static void
1006 vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
1007 {
1008         struct vhost_scsi_tpg **vs_tpg, *tpg;
1009         struct virtio_scsi_cmd_req v_req;
1010         struct virtio_scsi_cmd_req_pi v_req_pi;
1011         struct vhost_scsi_cmd *cmd;
1012         struct iov_iter out_iter, in_iter, prot_iter, data_iter;
1013         u64 tag;
1014         u32 exp_data_len, data_direction;
1015         unsigned out, in;
1016         int head, ret, prot_bytes;
1017         size_t req_size, rsp_size = sizeof(struct virtio_scsi_cmd_resp);
1018         size_t out_size, in_size;
1019         u16 lun;
1020         u8 *target, *lunp, task_attr;
1021         bool t10_pi = vhost_has_feature(vq, VIRTIO_SCSI_F_T10_PI);
1022         void *req, *cdb;
1023
1024         mutex_lock(&vq->mutex);
1025         /*
1026          * We can handle the vq only after the endpoint is setup by calling the
1027          * VHOST_SCSI_SET_ENDPOINT ioctl.
1028          */
1029         vs_tpg = vq->private_data;
1030         if (!vs_tpg)
1031                 goto out;
1032
1033         vhost_disable_notify(&vs->dev, vq);
1034
1035         for (;;) {
1036                 head = vhost_get_vq_desc(vq, vq->iov,
1037                                          ARRAY_SIZE(vq->iov), &out, &in,
1038                                          NULL, NULL);
1039                 pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n",
1040                          head, out, in);
1041                 /* On error, stop handling until the next kick. */
1042                 if (unlikely(head < 0))
1043                         break;
1044                 /* Nothing new?  Wait for eventfd to tell us they refilled. */
1045                 if (head == vq->num) {
1046                         if (unlikely(vhost_enable_notify(&vs->dev, vq))) {
1047                                 vhost_disable_notify(&vs->dev, vq);
1048                                 continue;
1049                         }
1050                         break;
1051                 }
1052                 /*
1053                  * Check for a sane response buffer so we can report early
1054                  * errors back to the guest.
1055                  */
1056                 if (unlikely(vq->iov[out].iov_len < rsp_size)) {
1057                         vq_err(vq, "Expecting at least virtio_scsi_cmd_resp"
1058                                 " size, got %zu bytes\n", vq->iov[out].iov_len);
1059                         break;
1060                 }
1061                 /*
1062                  * Setup pointers and values based upon different virtio-scsi
1063                  * request header if T10_PI is enabled in KVM guest.
1064                  */
1065                 if (t10_pi) {
1066                         req = &v_req_pi;
1067                         req_size = sizeof(v_req_pi);
1068                         lunp = &v_req_pi.lun[0];
1069                         target = &v_req_pi.lun[1];
1070                 } else {
1071                         req = &v_req;
1072                         req_size = sizeof(v_req);
1073                         lunp = &v_req.lun[0];
1074                         target = &v_req.lun[1];
1075                 }
1076                 /*
1077                  * FIXME: Not correct for BIDI operation
1078                  */
1079                 out_size = iov_length(vq->iov, out);
1080                 in_size = iov_length(&vq->iov[out], in);
1081
1082                 /*
1083                  * Copy over the virtio-scsi request header, which for a
1084                  * ANY_LAYOUT enabled guest may span multiple iovecs, or a
1085                  * single iovec may contain both the header + outgoing
1086                  * WRITE payloads.
1087                  *
1088                  * copy_from_iter() will advance out_iter, so that it will
1089                  * point at the start of the outgoing WRITE payload, if
1090                  * DMA_TO_DEVICE is set.
1091                  */
1092                 iov_iter_init(&out_iter, WRITE, vq->iov, out, out_size);
1093
1094                 ret = copy_from_iter(req, req_size, &out_iter);
1095                 if (unlikely(ret != req_size)) {
1096                         vq_err(vq, "Faulted on copy_from_iter\n");
1097                         vhost_scsi_send_bad_target(vs, vq, head, out);
1098                         continue;
1099                 }
1100                 /* virtio-scsi spec requires byte 0 of the lun to be 1 */
1101                 if (unlikely(*lunp != 1)) {
1102                         vq_err(vq, "Illegal virtio-scsi lun: %u\n", *lunp);
1103                         vhost_scsi_send_bad_target(vs, vq, head, out);
1104                         continue;
1105                 }
1106
1107                 tpg = ACCESS_ONCE(vs_tpg[*target]);
1108                 if (unlikely(!tpg)) {
1109                         /* Target does not exist, fail the request */
1110                         vhost_scsi_send_bad_target(vs, vq, head, out);
1111                         continue;
1112                 }
1113                 /*
1114                  * Determine data_direction by calculating the total outgoing
1115                  * iovec sizes + incoming iovec sizes vs. virtio-scsi request +
1116                  * response headers respectively.
1117                  *
1118                  * For DMA_TO_DEVICE this is out_iter, which is already pointing
1119                  * to the right place.
1120                  *
1121                  * For DMA_FROM_DEVICE, the iovec will be just past the end
1122                  * of the virtio-scsi response header in either the same
1123                  * or immediately following iovec.
1124                  *
1125                  * Any associated T10_PI bytes for the outgoing / incoming
1126                  * payloads are included in calculation of exp_data_len here.
1127                  */
1128                 prot_bytes = 0;
1129
1130                 if (out_size > req_size) {
1131                         data_direction = DMA_TO_DEVICE;
1132                         exp_data_len = out_size - req_size;
1133                         data_iter = out_iter;
1134                 } else if (in_size > rsp_size) {
1135                         data_direction = DMA_FROM_DEVICE;
1136                         exp_data_len = in_size - rsp_size;
1137
1138                         iov_iter_init(&in_iter, READ, &vq->iov[out], in,
1139                                       rsp_size + exp_data_len);
1140                         iov_iter_advance(&in_iter, rsp_size);
1141                         data_iter = in_iter;
1142                 } else {
1143                         data_direction = DMA_NONE;
1144                         exp_data_len = 0;
1145                 }
1146                 /*
1147                  * If T10_PI header + payload is present, setup prot_iter values
1148                  * and recalculate data_iter for vhost_scsi_mapal() mapping to
1149                  * host scatterlists via get_user_pages_fast().
1150                  */
1151                 if (t10_pi) {
1152                         if (v_req_pi.pi_bytesout) {
1153                                 if (data_direction != DMA_TO_DEVICE) {
1154                                         vq_err(vq, "Received non zero pi_bytesout,"
1155                                                 " but wrong data_direction\n");
1156                                         vhost_scsi_send_bad_target(vs, vq, head, out);
1157                                         continue;
1158                                 }
1159                                 prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesout);
1160                         } else if (v_req_pi.pi_bytesin) {
1161                                 if (data_direction != DMA_FROM_DEVICE) {
1162                                         vq_err(vq, "Received non zero pi_bytesin,"
1163                                                 " but wrong data_direction\n");
1164                                         vhost_scsi_send_bad_target(vs, vq, head, out);
1165                                         continue;
1166                                 }
1167                                 prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesin);
1168                         }
1169                         /*
1170                          * Set prot_iter to data_iter, and advance past any
1171                          * preceeding prot_bytes that may be present.
1172                          *
1173                          * Also fix up the exp_data_len to reflect only the
1174                          * actual data payload length.
1175                          */
1176                         if (prot_bytes) {
1177                                 exp_data_len -= prot_bytes;
1178                                 prot_iter = data_iter;
1179                                 iov_iter_advance(&data_iter, prot_bytes);
1180                         }
1181                         tag = vhost64_to_cpu(vq, v_req_pi.tag);
1182                         task_attr = v_req_pi.task_attr;
1183                         cdb = &v_req_pi.cdb[0];
1184                         lun = ((v_req_pi.lun[2] << 8) | v_req_pi.lun[3]) & 0x3FFF;
1185                 } else {
1186                         tag = vhost64_to_cpu(vq, v_req.tag);
1187                         task_attr = v_req.task_attr;
1188                         cdb = &v_req.cdb[0];
1189                         lun = ((v_req.lun[2] << 8) | v_req.lun[3]) & 0x3FFF;
1190                 }
1191                 /*
1192                  * Check that the received CDB size does not exceeded our
1193                  * hardcoded max for vhost-scsi, then get a pre-allocated
1194                  * cmd descriptor for the new virtio-scsi tag.
1195                  *
1196                  * TODO what if cdb was too small for varlen cdb header?
1197                  */
1198                 if (unlikely(scsi_command_size(cdb) > VHOST_SCSI_MAX_CDB_SIZE)) {
1199                         vq_err(vq, "Received SCSI CDB with command_size: %d that"
1200                                 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1201                                 scsi_command_size(cdb), VHOST_SCSI_MAX_CDB_SIZE);
1202                         vhost_scsi_send_bad_target(vs, vq, head, out);
1203                         continue;
1204                 }
1205                 cmd = vhost_scsi_get_tag(vq, tpg, cdb, tag, lun, task_attr,
1206                                          exp_data_len + prot_bytes,
1207                                          data_direction);
1208                 if (IS_ERR(cmd)) {
1209                         vq_err(vq, "vhost_scsi_get_tag failed %ld\n",
1210                                PTR_ERR(cmd));
1211                         vhost_scsi_send_bad_target(vs, vq, head, out);
1212                         continue;
1213                 }
1214                 cmd->tvc_vhost = vs;
1215                 cmd->tvc_vq = vq;
1216                 cmd->tvc_resp_iov = &vq->iov[out];
1217                 cmd->tvc_in_iovs = in;
1218
1219                 pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n",
1220                          cmd->tvc_cdb[0], cmd->tvc_lun);
1221                 pr_debug("cmd: %p exp_data_len: %d, prot_bytes: %d data_direction:"
1222                          " %d\n", cmd, exp_data_len, prot_bytes, data_direction);
1223
1224                 if (data_direction != DMA_NONE) {
1225                         ret = vhost_scsi_mapal(cmd,
1226                                                prot_bytes, &prot_iter,
1227                                                exp_data_len, &data_iter);
1228                         if (unlikely(ret)) {
1229                                 vq_err(vq, "Failed to map iov to sgl\n");
1230                                 vhost_scsi_release_cmd(&cmd->tvc_se_cmd);
1231                                 vhost_scsi_send_bad_target(vs, vq, head, out);
1232                                 continue;
1233                         }
1234                 }
1235                 /*
1236                  * Save the descriptor from vhost_get_vq_desc() to be used to
1237                  * complete the virtio-scsi request in TCM callback context via
1238                  * vhost_scsi_queue_data_in() and vhost_scsi_queue_status()
1239                  */
1240                 cmd->tvc_vq_desc = head;
1241                 /*
1242                  * Dispatch cmd descriptor for cmwq execution in process
1243                  * context provided by vhost_scsi_workqueue.  This also ensures
1244                  * cmd is executed on the same kworker CPU as this vhost
1245                  * thread to gain positive L2 cache locality effects.
1246                  */
1247                 INIT_WORK(&cmd->work, vhost_scsi_submission_work);
1248                 queue_work(vhost_scsi_workqueue, &cmd->work);
1249         }
1250 out:
1251         mutex_unlock(&vq->mutex);
1252 }
1253
1254 static void vhost_scsi_ctl_handle_kick(struct vhost_work *work)
1255 {
1256         pr_debug("%s: The handling func for control queue.\n", __func__);
1257 }
1258
1259 static void
1260 vhost_scsi_send_evt(struct vhost_scsi *vs,
1261                    struct vhost_scsi_tpg *tpg,
1262                    struct se_lun *lun,
1263                    u32 event,
1264                    u32 reason)
1265 {
1266         struct vhost_scsi_evt *evt;
1267
1268         evt = vhost_scsi_allocate_evt(vs, event, reason);
1269         if (!evt)
1270                 return;
1271
1272         if (tpg && lun) {
1273                 /* TODO: share lun setup code with virtio-scsi.ko */
1274                 /*
1275                  * Note: evt->event is zeroed when we allocate it and
1276                  * lun[4-7] need to be zero according to virtio-scsi spec.
1277                  */
1278                 evt->event.lun[0] = 0x01;
1279                 evt->event.lun[1] = tpg->tport_tpgt;
1280                 if (lun->unpacked_lun >= 256)
1281                         evt->event.lun[2] = lun->unpacked_lun >> 8 | 0x40 ;
1282                 evt->event.lun[3] = lun->unpacked_lun & 0xFF;
1283         }
1284
1285         llist_add(&evt->list, &vs->vs_event_list);
1286         vhost_work_queue(&vs->dev, &vs->vs_event_work);
1287 }
1288
1289 static void vhost_scsi_evt_handle_kick(struct vhost_work *work)
1290 {
1291         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1292                                                 poll.work);
1293         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1294
1295         mutex_lock(&vq->mutex);
1296         if (!vq->private_data)
1297                 goto out;
1298
1299         if (vs->vs_events_missed)
1300                 vhost_scsi_send_evt(vs, NULL, NULL, VIRTIO_SCSI_T_NO_EVENT, 0);
1301 out:
1302         mutex_unlock(&vq->mutex);
1303 }
1304
1305 static void vhost_scsi_handle_kick(struct vhost_work *work)
1306 {
1307         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1308                                                 poll.work);
1309         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1310
1311         vhost_scsi_handle_vq(vs, vq);
1312 }
1313
1314 static void vhost_scsi_flush_vq(struct vhost_scsi *vs, int index)
1315 {
1316         vhost_poll_flush(&vs->vqs[index].vq.poll);
1317 }
1318
1319 /* Callers must hold dev mutex */
1320 static void vhost_scsi_flush(struct vhost_scsi *vs)
1321 {
1322         struct vhost_scsi_inflight *old_inflight[VHOST_SCSI_MAX_VQ];
1323         int i;
1324
1325         /* Init new inflight and remember the old inflight */
1326         vhost_scsi_init_inflight(vs, old_inflight);
1327
1328         /*
1329          * The inflight->kref was initialized to 1. We decrement it here to
1330          * indicate the start of the flush operation so that it will reach 0
1331          * when all the reqs are finished.
1332          */
1333         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1334                 kref_put(&old_inflight[i]->kref, vhost_scsi_done_inflight);
1335
1336         /* Flush both the vhost poll and vhost work */
1337         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1338                 vhost_scsi_flush_vq(vs, i);
1339         vhost_work_flush(&vs->dev, &vs->vs_completion_work);
1340         vhost_work_flush(&vs->dev, &vs->vs_event_work);
1341
1342         /* Wait for all reqs issued before the flush to be finished */
1343         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1344                 wait_for_completion(&old_inflight[i]->comp);
1345 }
1346
1347 /*
1348  * Called from vhost_scsi_ioctl() context to walk the list of available
1349  * vhost_scsi_tpg with an active struct vhost_scsi_nexus
1350  *
1351  *  The lock nesting rule is:
1352  *    vhost_scsi_mutex -> vs->dev.mutex -> tpg->tv_tpg_mutex -> vq->mutex
1353  */
1354 static int
1355 vhost_scsi_set_endpoint(struct vhost_scsi *vs,
1356                         struct vhost_scsi_target *t)
1357 {
1358         struct se_portal_group *se_tpg;
1359         struct vhost_scsi_tport *tv_tport;
1360         struct vhost_scsi_tpg *tpg;
1361         struct vhost_scsi_tpg **vs_tpg;
1362         struct vhost_virtqueue *vq;
1363         int index, ret, i, len;
1364         bool match = false;
1365
1366         mutex_lock(&vhost_scsi_mutex);
1367         mutex_lock(&vs->dev.mutex);
1368
1369         /* Verify that ring has been setup correctly. */
1370         for (index = 0; index < vs->dev.nvqs; ++index) {
1371                 /* Verify that ring has been setup correctly. */
1372                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1373                         ret = -EFAULT;
1374                         goto out;
1375                 }
1376         }
1377
1378         len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET;
1379         vs_tpg = kzalloc(len, GFP_KERNEL);
1380         if (!vs_tpg) {
1381                 ret = -ENOMEM;
1382                 goto out;
1383         }
1384         if (vs->vs_tpg)
1385                 memcpy(vs_tpg, vs->vs_tpg, len);
1386
1387         list_for_each_entry(tpg, &vhost_scsi_list, tv_tpg_list) {
1388                 mutex_lock(&tpg->tv_tpg_mutex);
1389                 if (!tpg->tpg_nexus) {
1390                         mutex_unlock(&tpg->tv_tpg_mutex);
1391                         continue;
1392                 }
1393                 if (tpg->tv_tpg_vhost_count != 0) {
1394                         mutex_unlock(&tpg->tv_tpg_mutex);
1395                         continue;
1396                 }
1397                 tv_tport = tpg->tport;
1398
1399                 if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1400                         if (vs->vs_tpg && vs->vs_tpg[tpg->tport_tpgt]) {
1401                                 kfree(vs_tpg);
1402                                 mutex_unlock(&tpg->tv_tpg_mutex);
1403                                 ret = -EEXIST;
1404                                 goto out;
1405                         }
1406                         /*
1407                          * In order to ensure individual vhost-scsi configfs
1408                          * groups cannot be removed while in use by vhost ioctl,
1409                          * go ahead and take an explicit se_tpg->tpg_group.cg_item
1410                          * dependency now.
1411                          */
1412                         se_tpg = &tpg->se_tpg;
1413                         ret = target_depend_item(&se_tpg->tpg_group.cg_item);
1414                         if (ret) {
1415                                 pr_warn("configfs_depend_item() failed: %d\n", ret);
1416                                 kfree(vs_tpg);
1417                                 mutex_unlock(&tpg->tv_tpg_mutex);
1418                                 goto out;
1419                         }
1420                         tpg->tv_tpg_vhost_count++;
1421                         tpg->vhost_scsi = vs;
1422                         vs_tpg[tpg->tport_tpgt] = tpg;
1423                         smp_mb__after_atomic();
1424                         match = true;
1425                 }
1426                 mutex_unlock(&tpg->tv_tpg_mutex);
1427         }
1428
1429         if (match) {
1430                 memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
1431                        sizeof(vs->vs_vhost_wwpn));
1432                 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1433                         vq = &vs->vqs[i].vq;
1434                         mutex_lock(&vq->mutex);
1435                         vq->private_data = vs_tpg;
1436                         vhost_init_used(vq);
1437                         mutex_unlock(&vq->mutex);
1438                 }
1439                 ret = 0;
1440         } else {
1441                 ret = -EEXIST;
1442         }
1443
1444         /*
1445          * Act as synchronize_rcu to make sure access to
1446          * old vs->vs_tpg is finished.
1447          */
1448         vhost_scsi_flush(vs);
1449         kfree(vs->vs_tpg);
1450         vs->vs_tpg = vs_tpg;
1451
1452 out:
1453         mutex_unlock(&vs->dev.mutex);
1454         mutex_unlock(&vhost_scsi_mutex);
1455         return ret;
1456 }
1457
1458 static int
1459 vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
1460                           struct vhost_scsi_target *t)
1461 {
1462         struct se_portal_group *se_tpg;
1463         struct vhost_scsi_tport *tv_tport;
1464         struct vhost_scsi_tpg *tpg;
1465         struct vhost_virtqueue *vq;
1466         bool match = false;
1467         int index, ret, i;
1468         u8 target;
1469
1470         mutex_lock(&vhost_scsi_mutex);
1471         mutex_lock(&vs->dev.mutex);
1472         /* Verify that ring has been setup correctly. */
1473         for (index = 0; index < vs->dev.nvqs; ++index) {
1474                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1475                         ret = -EFAULT;
1476                         goto err_dev;
1477                 }
1478         }
1479
1480         if (!vs->vs_tpg) {
1481                 ret = 0;
1482                 goto err_dev;
1483         }
1484
1485         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1486                 target = i;
1487                 tpg = vs->vs_tpg[target];
1488                 if (!tpg)
1489                         continue;
1490
1491                 mutex_lock(&tpg->tv_tpg_mutex);
1492                 tv_tport = tpg->tport;
1493                 if (!tv_tport) {
1494                         ret = -ENODEV;
1495                         goto err_tpg;
1496                 }
1497
1498                 if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1499                         pr_warn("tv_tport->tport_name: %s, tpg->tport_tpgt: %hu"
1500                                 " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
1501                                 tv_tport->tport_name, tpg->tport_tpgt,
1502                                 t->vhost_wwpn, t->vhost_tpgt);
1503                         ret = -EINVAL;
1504                         goto err_tpg;
1505                 }
1506                 tpg->tv_tpg_vhost_count--;
1507                 tpg->vhost_scsi = NULL;
1508                 vs->vs_tpg[target] = NULL;
1509                 match = true;
1510                 mutex_unlock(&tpg->tv_tpg_mutex);
1511                 /*
1512                  * Release se_tpg->tpg_group.cg_item configfs dependency now
1513                  * to allow vhost-scsi WWPN se_tpg->tpg_group shutdown to occur.
1514                  */
1515                 se_tpg = &tpg->se_tpg;
1516                 target_undepend_item(&se_tpg->tpg_group.cg_item);
1517         }
1518         if (match) {
1519                 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1520                         vq = &vs->vqs[i].vq;
1521                         mutex_lock(&vq->mutex);
1522                         vq->private_data = NULL;
1523                         mutex_unlock(&vq->mutex);
1524                 }
1525         }
1526         /*
1527          * Act as synchronize_rcu to make sure access to
1528          * old vs->vs_tpg is finished.
1529          */
1530         vhost_scsi_flush(vs);
1531         kfree(vs->vs_tpg);
1532         vs->vs_tpg = NULL;
1533         WARN_ON(vs->vs_events_nr);
1534         mutex_unlock(&vs->dev.mutex);
1535         mutex_unlock(&vhost_scsi_mutex);
1536         return 0;
1537
1538 err_tpg:
1539         mutex_unlock(&tpg->tv_tpg_mutex);
1540 err_dev:
1541         mutex_unlock(&vs->dev.mutex);
1542         mutex_unlock(&vhost_scsi_mutex);
1543         return ret;
1544 }
1545
1546 static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features)
1547 {
1548         struct vhost_virtqueue *vq;
1549         int i;
1550
1551         if (features & ~VHOST_SCSI_FEATURES)
1552                 return -EOPNOTSUPP;
1553
1554         mutex_lock(&vs->dev.mutex);
1555         if ((features & (1 << VHOST_F_LOG_ALL)) &&
1556             !vhost_log_access_ok(&vs->dev)) {
1557                 mutex_unlock(&vs->dev.mutex);
1558                 return -EFAULT;
1559         }
1560
1561         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1562                 vq = &vs->vqs[i].vq;
1563                 mutex_lock(&vq->mutex);
1564                 vq->acked_features = features;
1565                 mutex_unlock(&vq->mutex);
1566         }
1567         mutex_unlock(&vs->dev.mutex);
1568         return 0;
1569 }
1570
1571 static int vhost_scsi_open(struct inode *inode, struct file *f)
1572 {
1573         struct vhost_scsi *vs;
1574         struct vhost_virtqueue **vqs;
1575         int r = -ENOMEM, i;
1576
1577         vs = kzalloc(sizeof(*vs), GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
1578         if (!vs) {
1579                 vs = vzalloc(sizeof(*vs));
1580                 if (!vs)
1581                         goto err_vs;
1582         }
1583
1584         vqs = kmalloc(VHOST_SCSI_MAX_VQ * sizeof(*vqs), GFP_KERNEL);
1585         if (!vqs)
1586                 goto err_vqs;
1587
1588         vhost_work_init(&vs->vs_completion_work, vhost_scsi_complete_cmd_work);
1589         vhost_work_init(&vs->vs_event_work, vhost_scsi_evt_work);
1590
1591         vs->vs_events_nr = 0;
1592         vs->vs_events_missed = false;
1593
1594         vqs[VHOST_SCSI_VQ_CTL] = &vs->vqs[VHOST_SCSI_VQ_CTL].vq;
1595         vqs[VHOST_SCSI_VQ_EVT] = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1596         vs->vqs[VHOST_SCSI_VQ_CTL].vq.handle_kick = vhost_scsi_ctl_handle_kick;
1597         vs->vqs[VHOST_SCSI_VQ_EVT].vq.handle_kick = vhost_scsi_evt_handle_kick;
1598         for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++) {
1599                 vqs[i] = &vs->vqs[i].vq;
1600                 vs->vqs[i].vq.handle_kick = vhost_scsi_handle_kick;
1601         }
1602         vhost_dev_init(&vs->dev, vqs, VHOST_SCSI_MAX_VQ);
1603
1604         vhost_scsi_init_inflight(vs, NULL);
1605
1606         f->private_data = vs;
1607         return 0;
1608
1609 err_vqs:
1610         kvfree(vs);
1611 err_vs:
1612         return r;
1613 }
1614
1615 static int vhost_scsi_release(struct inode *inode, struct file *f)
1616 {
1617         struct vhost_scsi *vs = f->private_data;
1618         struct vhost_scsi_target t;
1619
1620         mutex_lock(&vs->dev.mutex);
1621         memcpy(t.vhost_wwpn, vs->vs_vhost_wwpn, sizeof(t.vhost_wwpn));
1622         mutex_unlock(&vs->dev.mutex);
1623         vhost_scsi_clear_endpoint(vs, &t);
1624         vhost_dev_stop(&vs->dev);
1625         vhost_dev_cleanup(&vs->dev, false);
1626         /* Jobs can re-queue themselves in evt kick handler. Do extra flush. */
1627         vhost_scsi_flush(vs);
1628         kfree(vs->dev.vqs);
1629         kvfree(vs);
1630         return 0;
1631 }
1632
1633 static long
1634 vhost_scsi_ioctl(struct file *f,
1635                  unsigned int ioctl,
1636                  unsigned long arg)
1637 {
1638         struct vhost_scsi *vs = f->private_data;
1639         struct vhost_scsi_target backend;
1640         void __user *argp = (void __user *)arg;
1641         u64 __user *featurep = argp;
1642         u32 __user *eventsp = argp;
1643         u32 events_missed;
1644         u64 features;
1645         int r, abi_version = VHOST_SCSI_ABI_VERSION;
1646         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1647
1648         switch (ioctl) {
1649         case VHOST_SCSI_SET_ENDPOINT:
1650                 if (copy_from_user(&backend, argp, sizeof backend))
1651                         return -EFAULT;
1652                 if (backend.reserved != 0)
1653                         return -EOPNOTSUPP;
1654
1655                 return vhost_scsi_set_endpoint(vs, &backend);
1656         case VHOST_SCSI_CLEAR_ENDPOINT:
1657                 if (copy_from_user(&backend, argp, sizeof backend))
1658                         return -EFAULT;
1659                 if (backend.reserved != 0)
1660                         return -EOPNOTSUPP;
1661
1662                 return vhost_scsi_clear_endpoint(vs, &backend);
1663         case VHOST_SCSI_GET_ABI_VERSION:
1664                 if (copy_to_user(argp, &abi_version, sizeof abi_version))
1665                         return -EFAULT;
1666                 return 0;
1667         case VHOST_SCSI_SET_EVENTS_MISSED:
1668                 if (get_user(events_missed, eventsp))
1669                         return -EFAULT;
1670                 mutex_lock(&vq->mutex);
1671                 vs->vs_events_missed = events_missed;
1672                 mutex_unlock(&vq->mutex);
1673                 return 0;
1674         case VHOST_SCSI_GET_EVENTS_MISSED:
1675                 mutex_lock(&vq->mutex);
1676                 events_missed = vs->vs_events_missed;
1677                 mutex_unlock(&vq->mutex);
1678                 if (put_user(events_missed, eventsp))
1679                         return -EFAULT;
1680                 return 0;
1681         case VHOST_GET_FEATURES:
1682                 features = VHOST_SCSI_FEATURES;
1683                 if (copy_to_user(featurep, &features, sizeof features))
1684                         return -EFAULT;
1685                 return 0;
1686         case VHOST_SET_FEATURES:
1687                 if (copy_from_user(&features, featurep, sizeof features))
1688                         return -EFAULT;
1689                 return vhost_scsi_set_features(vs, features);
1690         default:
1691                 mutex_lock(&vs->dev.mutex);
1692                 r = vhost_dev_ioctl(&vs->dev, ioctl, argp);
1693                 /* TODO: flush backend after dev ioctl. */
1694                 if (r == -ENOIOCTLCMD)
1695                         r = vhost_vring_ioctl(&vs->dev, ioctl, argp);
1696                 mutex_unlock(&vs->dev.mutex);
1697                 return r;
1698         }
1699 }
1700
1701 #ifdef CONFIG_COMPAT
1702 static long vhost_scsi_compat_ioctl(struct file *f, unsigned int ioctl,
1703                                 unsigned long arg)
1704 {
1705         return vhost_scsi_ioctl(f, ioctl, (unsigned long)compat_ptr(arg));
1706 }
1707 #endif
1708
1709 static const struct file_operations vhost_scsi_fops = {
1710         .owner          = THIS_MODULE,
1711         .release        = vhost_scsi_release,
1712         .unlocked_ioctl = vhost_scsi_ioctl,
1713 #ifdef CONFIG_COMPAT
1714         .compat_ioctl   = vhost_scsi_compat_ioctl,
1715 #endif
1716         .open           = vhost_scsi_open,
1717         .llseek         = noop_llseek,
1718 };
1719
1720 static struct miscdevice vhost_scsi_misc = {
1721         MISC_DYNAMIC_MINOR,
1722         "vhost-scsi",
1723         &vhost_scsi_fops,
1724 };
1725
1726 static int __init vhost_scsi_register(void)
1727 {
1728         return misc_register(&vhost_scsi_misc);
1729 }
1730
1731 static int vhost_scsi_deregister(void)
1732 {
1733         return misc_deregister(&vhost_scsi_misc);
1734 }
1735
1736 static char *vhost_scsi_dump_proto_id(struct vhost_scsi_tport *tport)
1737 {
1738         switch (tport->tport_proto_id) {
1739         case SCSI_PROTOCOL_SAS:
1740                 return "SAS";
1741         case SCSI_PROTOCOL_FCP:
1742                 return "FCP";
1743         case SCSI_PROTOCOL_ISCSI:
1744                 return "iSCSI";
1745         default:
1746                 break;
1747         }
1748
1749         return "Unknown";
1750 }
1751
1752 static void
1753 vhost_scsi_do_plug(struct vhost_scsi_tpg *tpg,
1754                   struct se_lun *lun, bool plug)
1755 {
1756
1757         struct vhost_scsi *vs = tpg->vhost_scsi;
1758         struct vhost_virtqueue *vq;
1759         u32 reason;
1760
1761         if (!vs)
1762                 return;
1763
1764         mutex_lock(&vs->dev.mutex);
1765
1766         if (plug)
1767                 reason = VIRTIO_SCSI_EVT_RESET_RESCAN;
1768         else
1769                 reason = VIRTIO_SCSI_EVT_RESET_REMOVED;
1770
1771         vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1772         mutex_lock(&vq->mutex);
1773         if (vhost_has_feature(vq, VIRTIO_SCSI_F_HOTPLUG))
1774                 vhost_scsi_send_evt(vs, tpg, lun,
1775                                    VIRTIO_SCSI_T_TRANSPORT_RESET, reason);
1776         mutex_unlock(&vq->mutex);
1777         mutex_unlock(&vs->dev.mutex);
1778 }
1779
1780 static void vhost_scsi_hotplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
1781 {
1782         vhost_scsi_do_plug(tpg, lun, true);
1783 }
1784
1785 static void vhost_scsi_hotunplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
1786 {
1787         vhost_scsi_do_plug(tpg, lun, false);
1788 }
1789
1790 static int vhost_scsi_port_link(struct se_portal_group *se_tpg,
1791                                struct se_lun *lun)
1792 {
1793         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
1794                                 struct vhost_scsi_tpg, se_tpg);
1795
1796         mutex_lock(&vhost_scsi_mutex);
1797
1798         mutex_lock(&tpg->tv_tpg_mutex);
1799         tpg->tv_tpg_port_count++;
1800         mutex_unlock(&tpg->tv_tpg_mutex);
1801
1802         vhost_scsi_hotplug(tpg, lun);
1803
1804         mutex_unlock(&vhost_scsi_mutex);
1805
1806         return 0;
1807 }
1808
1809 static void vhost_scsi_port_unlink(struct se_portal_group *se_tpg,
1810                                   struct se_lun *lun)
1811 {
1812         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
1813                                 struct vhost_scsi_tpg, se_tpg);
1814
1815         mutex_lock(&vhost_scsi_mutex);
1816
1817         mutex_lock(&tpg->tv_tpg_mutex);
1818         tpg->tv_tpg_port_count--;
1819         mutex_unlock(&tpg->tv_tpg_mutex);
1820
1821         vhost_scsi_hotunplug(tpg, lun);
1822
1823         mutex_unlock(&vhost_scsi_mutex);
1824 }
1825
1826 static struct se_node_acl *
1827 vhost_scsi_make_nodeacl(struct se_portal_group *se_tpg,
1828                        struct config_group *group,
1829                        const char *name)
1830 {
1831         struct se_node_acl *se_nacl, *se_nacl_new;
1832         struct vhost_scsi_nacl *nacl;
1833         u64 wwpn = 0;
1834         u32 nexus_depth;
1835
1836         /* vhost_scsi_parse_wwn(name, &wwpn, 1) < 0)
1837                 return ERR_PTR(-EINVAL); */
1838         se_nacl_new = vhost_scsi_alloc_fabric_acl(se_tpg);
1839         if (!se_nacl_new)
1840                 return ERR_PTR(-ENOMEM);
1841
1842         nexus_depth = 1;
1843         /*
1844          * se_nacl_new may be released by core_tpg_add_initiator_node_acl()
1845          * when converting a NodeACL from demo mode -> explict
1846          */
1847         se_nacl = core_tpg_add_initiator_node_acl(se_tpg, se_nacl_new,
1848                                 name, nexus_depth);
1849         if (IS_ERR(se_nacl)) {
1850                 vhost_scsi_release_fabric_acl(se_tpg, se_nacl_new);
1851                 return se_nacl;
1852         }
1853         /*
1854          * Locate our struct vhost_scsi_nacl and set the FC Nport WWPN
1855          */
1856         nacl = container_of(se_nacl, struct vhost_scsi_nacl, se_node_acl);
1857         nacl->iport_wwpn = wwpn;
1858
1859         return se_nacl;
1860 }
1861
1862 static void vhost_scsi_drop_nodeacl(struct se_node_acl *se_acl)
1863 {
1864         struct vhost_scsi_nacl *nacl = container_of(se_acl,
1865                                 struct vhost_scsi_nacl, se_node_acl);
1866         core_tpg_del_initiator_node_acl(se_acl->se_tpg, se_acl, 1);
1867         kfree(nacl);
1868 }
1869
1870 static void vhost_scsi_free_cmd_map_res(struct vhost_scsi_nexus *nexus,
1871                                        struct se_session *se_sess)
1872 {
1873         struct vhost_scsi_cmd *tv_cmd;
1874         unsigned int i;
1875
1876         if (!se_sess->sess_cmd_map)
1877                 return;
1878
1879         for (i = 0; i < VHOST_SCSI_DEFAULT_TAGS; i++) {
1880                 tv_cmd = &((struct vhost_scsi_cmd *)se_sess->sess_cmd_map)[i];
1881
1882                 kfree(tv_cmd->tvc_sgl);
1883                 kfree(tv_cmd->tvc_prot_sgl);
1884                 kfree(tv_cmd->tvc_upages);
1885         }
1886 }
1887
1888 static ssize_t vhost_scsi_tpg_attrib_store_fabric_prot_type(
1889         struct se_portal_group *se_tpg,
1890         const char *page,
1891         size_t count)
1892 {
1893         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
1894                                 struct vhost_scsi_tpg, se_tpg);
1895         unsigned long val;
1896         int ret = kstrtoul(page, 0, &val);
1897
1898         if (ret) {
1899                 pr_err("kstrtoul() returned %d for fabric_prot_type\n", ret);
1900                 return ret;
1901         }
1902         if (val != 0 && val != 1 && val != 3) {
1903                 pr_err("Invalid vhost_scsi fabric_prot_type: %lu\n", val);
1904                 return -EINVAL;
1905         }
1906         tpg->tv_fabric_prot_type = val;
1907
1908         return count;
1909 }
1910
1911 static ssize_t vhost_scsi_tpg_attrib_show_fabric_prot_type(
1912         struct se_portal_group *se_tpg,
1913         char *page)
1914 {
1915         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
1916                                 struct vhost_scsi_tpg, se_tpg);
1917
1918         return sprintf(page, "%d\n", tpg->tv_fabric_prot_type);
1919 }
1920 TF_TPG_ATTRIB_ATTR(vhost_scsi, fabric_prot_type, S_IRUGO | S_IWUSR);
1921
1922 static struct configfs_attribute *vhost_scsi_tpg_attrib_attrs[] = {
1923         &vhost_scsi_tpg_attrib_fabric_prot_type.attr,
1924         NULL,
1925 };
1926
1927 static int vhost_scsi_make_nexus(struct vhost_scsi_tpg *tpg,
1928                                 const char *name)
1929 {
1930         struct se_portal_group *se_tpg;
1931         struct se_session *se_sess;
1932         struct vhost_scsi_nexus *tv_nexus;
1933         struct vhost_scsi_cmd *tv_cmd;
1934         unsigned int i;
1935
1936         mutex_lock(&tpg->tv_tpg_mutex);
1937         if (tpg->tpg_nexus) {
1938                 mutex_unlock(&tpg->tv_tpg_mutex);
1939                 pr_debug("tpg->tpg_nexus already exists\n");
1940                 return -EEXIST;
1941         }
1942         se_tpg = &tpg->se_tpg;
1943
1944         tv_nexus = kzalloc(sizeof(struct vhost_scsi_nexus), GFP_KERNEL);
1945         if (!tv_nexus) {
1946                 mutex_unlock(&tpg->tv_tpg_mutex);
1947                 pr_err("Unable to allocate struct vhost_scsi_nexus\n");
1948                 return -ENOMEM;
1949         }
1950         /*
1951          *  Initialize the struct se_session pointer and setup tagpool
1952          *  for struct vhost_scsi_cmd descriptors
1953          */
1954         tv_nexus->tvn_se_sess = transport_init_session_tags(
1955                                         VHOST_SCSI_DEFAULT_TAGS,
1956                                         sizeof(struct vhost_scsi_cmd),
1957                                         TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS);
1958         if (IS_ERR(tv_nexus->tvn_se_sess)) {
1959                 mutex_unlock(&tpg->tv_tpg_mutex);
1960                 kfree(tv_nexus);
1961                 return -ENOMEM;
1962         }
1963         se_sess = tv_nexus->tvn_se_sess;
1964         for (i = 0; i < VHOST_SCSI_DEFAULT_TAGS; i++) {
1965                 tv_cmd = &((struct vhost_scsi_cmd *)se_sess->sess_cmd_map)[i];
1966
1967                 tv_cmd->tvc_sgl = kzalloc(sizeof(struct scatterlist) *
1968                                         VHOST_SCSI_PREALLOC_SGLS, GFP_KERNEL);
1969                 if (!tv_cmd->tvc_sgl) {
1970                         mutex_unlock(&tpg->tv_tpg_mutex);
1971                         pr_err("Unable to allocate tv_cmd->tvc_sgl\n");
1972                         goto out;
1973                 }
1974
1975                 tv_cmd->tvc_upages = kzalloc(sizeof(struct page *) *
1976                                         VHOST_SCSI_PREALLOC_UPAGES, GFP_KERNEL);
1977                 if (!tv_cmd->tvc_upages) {
1978                         mutex_unlock(&tpg->tv_tpg_mutex);
1979                         pr_err("Unable to allocate tv_cmd->tvc_upages\n");
1980                         goto out;
1981                 }
1982
1983                 tv_cmd->tvc_prot_sgl = kzalloc(sizeof(struct scatterlist) *
1984                                         VHOST_SCSI_PREALLOC_PROT_SGLS, GFP_KERNEL);
1985                 if (!tv_cmd->tvc_prot_sgl) {
1986                         mutex_unlock(&tpg->tv_tpg_mutex);
1987                         pr_err("Unable to allocate tv_cmd->tvc_prot_sgl\n");
1988                         goto out;
1989                 }
1990         }
1991         /*
1992          * Since we are running in 'demo mode' this call with generate a
1993          * struct se_node_acl for the vhost_scsi struct se_portal_group with
1994          * the SCSI Initiator port name of the passed configfs group 'name'.
1995          */
1996         tv_nexus->tvn_se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
1997                                 se_tpg, (unsigned char *)name);
1998         if (!tv_nexus->tvn_se_sess->se_node_acl) {
1999                 mutex_unlock(&tpg->tv_tpg_mutex);
2000                 pr_debug("core_tpg_check_initiator_node_acl() failed"
2001                                 " for %s\n", name);
2002                 goto out;
2003         }
2004         /*
2005          * Now register the TCM vhost virtual I_T Nexus as active.
2006          */
2007         transport_register_session(se_tpg, tv_nexus->tvn_se_sess->se_node_acl,
2008                         tv_nexus->tvn_se_sess, tv_nexus);
2009         tpg->tpg_nexus = tv_nexus;
2010
2011         mutex_unlock(&tpg->tv_tpg_mutex);
2012         return 0;
2013
2014 out:
2015         vhost_scsi_free_cmd_map_res(tv_nexus, se_sess);
2016         transport_free_session(se_sess);
2017         kfree(tv_nexus);
2018         return -ENOMEM;
2019 }
2020
2021 static int vhost_scsi_drop_nexus(struct vhost_scsi_tpg *tpg)
2022 {
2023         struct se_session *se_sess;
2024         struct vhost_scsi_nexus *tv_nexus;
2025
2026         mutex_lock(&tpg->tv_tpg_mutex);
2027         tv_nexus = tpg->tpg_nexus;
2028         if (!tv_nexus) {
2029                 mutex_unlock(&tpg->tv_tpg_mutex);
2030                 return -ENODEV;
2031         }
2032
2033         se_sess = tv_nexus->tvn_se_sess;
2034         if (!se_sess) {
2035                 mutex_unlock(&tpg->tv_tpg_mutex);
2036                 return -ENODEV;
2037         }
2038
2039         if (tpg->tv_tpg_port_count != 0) {
2040                 mutex_unlock(&tpg->tv_tpg_mutex);
2041                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
2042                         " active TPG port count: %d\n",
2043                         tpg->tv_tpg_port_count);
2044                 return -EBUSY;
2045         }
2046
2047         if (tpg->tv_tpg_vhost_count != 0) {
2048                 mutex_unlock(&tpg->tv_tpg_mutex);
2049                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
2050                         " active TPG vhost count: %d\n",
2051                         tpg->tv_tpg_vhost_count);
2052                 return -EBUSY;
2053         }
2054
2055         pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated"
2056                 " %s Initiator Port: %s\n", vhost_scsi_dump_proto_id(tpg->tport),
2057                 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
2058
2059         vhost_scsi_free_cmd_map_res(tv_nexus, se_sess);
2060         /*
2061          * Release the SCSI I_T Nexus to the emulated vhost Target Port
2062          */
2063         transport_deregister_session(tv_nexus->tvn_se_sess);
2064         tpg->tpg_nexus = NULL;
2065         mutex_unlock(&tpg->tv_tpg_mutex);
2066
2067         kfree(tv_nexus);
2068         return 0;
2069 }
2070
2071 static ssize_t vhost_scsi_tpg_show_nexus(struct se_portal_group *se_tpg,
2072                                         char *page)
2073 {
2074         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2075                                 struct vhost_scsi_tpg, se_tpg);
2076         struct vhost_scsi_nexus *tv_nexus;
2077         ssize_t ret;
2078
2079         mutex_lock(&tpg->tv_tpg_mutex);
2080         tv_nexus = tpg->tpg_nexus;
2081         if (!tv_nexus) {
2082                 mutex_unlock(&tpg->tv_tpg_mutex);
2083                 return -ENODEV;
2084         }
2085         ret = snprintf(page, PAGE_SIZE, "%s\n",
2086                         tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
2087         mutex_unlock(&tpg->tv_tpg_mutex);
2088
2089         return ret;
2090 }
2091
2092 static ssize_t vhost_scsi_tpg_store_nexus(struct se_portal_group *se_tpg,
2093                                          const char *page,
2094                                          size_t count)
2095 {
2096         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2097                                 struct vhost_scsi_tpg, se_tpg);
2098         struct vhost_scsi_tport *tport_wwn = tpg->tport;
2099         unsigned char i_port[VHOST_SCSI_NAMELEN], *ptr, *port_ptr;
2100         int ret;
2101         /*
2102          * Shutdown the active I_T nexus if 'NULL' is passed..
2103          */
2104         if (!strncmp(page, "NULL", 4)) {
2105                 ret = vhost_scsi_drop_nexus(tpg);
2106                 return (!ret) ? count : ret;
2107         }
2108         /*
2109          * Otherwise make sure the passed virtual Initiator port WWN matches
2110          * the fabric protocol_id set in vhost_scsi_make_tport(), and call
2111          * vhost_scsi_make_nexus().
2112          */
2113         if (strlen(page) >= VHOST_SCSI_NAMELEN) {
2114                 pr_err("Emulated NAA Sas Address: %s, exceeds"
2115                                 " max: %d\n", page, VHOST_SCSI_NAMELEN);
2116                 return -EINVAL;
2117         }
2118         snprintf(&i_port[0], VHOST_SCSI_NAMELEN, "%s", page);
2119
2120         ptr = strstr(i_port, "naa.");
2121         if (ptr) {
2122                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
2123                         pr_err("Passed SAS Initiator Port %s does not"
2124                                 " match target port protoid: %s\n", i_port,
2125                                 vhost_scsi_dump_proto_id(tport_wwn));
2126                         return -EINVAL;
2127                 }
2128                 port_ptr = &i_port[0];
2129                 goto check_newline;
2130         }
2131         ptr = strstr(i_port, "fc.");
2132         if (ptr) {
2133                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
2134                         pr_err("Passed FCP Initiator Port %s does not"
2135                                 " match target port protoid: %s\n", i_port,
2136                                 vhost_scsi_dump_proto_id(tport_wwn));
2137                         return -EINVAL;
2138                 }
2139                 port_ptr = &i_port[3]; /* Skip over "fc." */
2140                 goto check_newline;
2141         }
2142         ptr = strstr(i_port, "iqn.");
2143         if (ptr) {
2144                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
2145                         pr_err("Passed iSCSI Initiator Port %s does not"
2146                                 " match target port protoid: %s\n", i_port,
2147                                 vhost_scsi_dump_proto_id(tport_wwn));
2148                         return -EINVAL;
2149                 }
2150                 port_ptr = &i_port[0];
2151                 goto check_newline;
2152         }
2153         pr_err("Unable to locate prefix for emulated Initiator Port:"
2154                         " %s\n", i_port);
2155         return -EINVAL;
2156         /*
2157          * Clear any trailing newline for the NAA WWN
2158          */
2159 check_newline:
2160         if (i_port[strlen(i_port)-1] == '\n')
2161                 i_port[strlen(i_port)-1] = '\0';
2162
2163         ret = vhost_scsi_make_nexus(tpg, port_ptr);
2164         if (ret < 0)
2165                 return ret;
2166
2167         return count;
2168 }
2169
2170 TF_TPG_BASE_ATTR(vhost_scsi, nexus, S_IRUGO | S_IWUSR);
2171
2172 static struct configfs_attribute *vhost_scsi_tpg_attrs[] = {
2173         &vhost_scsi_tpg_nexus.attr,
2174         NULL,
2175 };
2176
2177 static struct se_portal_group *
2178 vhost_scsi_make_tpg(struct se_wwn *wwn,
2179                    struct config_group *group,
2180                    const char *name)
2181 {
2182         struct vhost_scsi_tport *tport = container_of(wwn,
2183                         struct vhost_scsi_tport, tport_wwn);
2184
2185         struct vhost_scsi_tpg *tpg;
2186         u16 tpgt;
2187         int ret;
2188
2189         if (strstr(name, "tpgt_") != name)
2190                 return ERR_PTR(-EINVAL);
2191         if (kstrtou16(name + 5, 10, &tpgt) || tpgt >= VHOST_SCSI_MAX_TARGET)
2192                 return ERR_PTR(-EINVAL);
2193
2194         tpg = kzalloc(sizeof(struct vhost_scsi_tpg), GFP_KERNEL);
2195         if (!tpg) {
2196                 pr_err("Unable to allocate struct vhost_scsi_tpg");
2197                 return ERR_PTR(-ENOMEM);
2198         }
2199         mutex_init(&tpg->tv_tpg_mutex);
2200         INIT_LIST_HEAD(&tpg->tv_tpg_list);
2201         tpg->tport = tport;
2202         tpg->tport_tpgt = tpgt;
2203
2204         ret = core_tpg_register(&vhost_scsi_ops, wwn,
2205                                 &tpg->se_tpg, tpg, TRANSPORT_TPG_TYPE_NORMAL);
2206         if (ret < 0) {
2207                 kfree(tpg);
2208                 return NULL;
2209         }
2210         mutex_lock(&vhost_scsi_mutex);
2211         list_add_tail(&tpg->tv_tpg_list, &vhost_scsi_list);
2212         mutex_unlock(&vhost_scsi_mutex);
2213
2214         return &tpg->se_tpg;
2215 }
2216
2217 static void vhost_scsi_drop_tpg(struct se_portal_group *se_tpg)
2218 {
2219         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2220                                 struct vhost_scsi_tpg, se_tpg);
2221
2222         mutex_lock(&vhost_scsi_mutex);
2223         list_del(&tpg->tv_tpg_list);
2224         mutex_unlock(&vhost_scsi_mutex);
2225         /*
2226          * Release the virtual I_T Nexus for this vhost TPG
2227          */
2228         vhost_scsi_drop_nexus(tpg);
2229         /*
2230          * Deregister the se_tpg from TCM..
2231          */
2232         core_tpg_deregister(se_tpg);
2233         kfree(tpg);
2234 }
2235
2236 static struct se_wwn *
2237 vhost_scsi_make_tport(struct target_fabric_configfs *tf,
2238                      struct config_group *group,
2239                      const char *name)
2240 {
2241         struct vhost_scsi_tport *tport;
2242         char *ptr;
2243         u64 wwpn = 0;
2244         int off = 0;
2245
2246         /* if (vhost_scsi_parse_wwn(name, &wwpn, 1) < 0)
2247                 return ERR_PTR(-EINVAL); */
2248
2249         tport = kzalloc(sizeof(struct vhost_scsi_tport), GFP_KERNEL);
2250         if (!tport) {
2251                 pr_err("Unable to allocate struct vhost_scsi_tport");
2252                 return ERR_PTR(-ENOMEM);
2253         }
2254         tport->tport_wwpn = wwpn;
2255         /*
2256          * Determine the emulated Protocol Identifier and Target Port Name
2257          * based on the incoming configfs directory name.
2258          */
2259         ptr = strstr(name, "naa.");
2260         if (ptr) {
2261                 tport->tport_proto_id = SCSI_PROTOCOL_SAS;
2262                 goto check_len;
2263         }
2264         ptr = strstr(name, "fc.");
2265         if (ptr) {
2266                 tport->tport_proto_id = SCSI_PROTOCOL_FCP;
2267                 off = 3; /* Skip over "fc." */
2268                 goto check_len;
2269         }
2270         ptr = strstr(name, "iqn.");
2271         if (ptr) {
2272                 tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
2273                 goto check_len;
2274         }
2275
2276         pr_err("Unable to locate prefix for emulated Target Port:"
2277                         " %s\n", name);
2278         kfree(tport);
2279         return ERR_PTR(-EINVAL);
2280
2281 check_len:
2282         if (strlen(name) >= VHOST_SCSI_NAMELEN) {
2283                 pr_err("Emulated %s Address: %s, exceeds"
2284                         " max: %d\n", name, vhost_scsi_dump_proto_id(tport),
2285                         VHOST_SCSI_NAMELEN);
2286                 kfree(tport);
2287                 return ERR_PTR(-EINVAL);
2288         }
2289         snprintf(&tport->tport_name[0], VHOST_SCSI_NAMELEN, "%s", &name[off]);
2290
2291         pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target"
2292                 " %s Address: %s\n", vhost_scsi_dump_proto_id(tport), name);
2293
2294         return &tport->tport_wwn;
2295 }
2296
2297 static void vhost_scsi_drop_tport(struct se_wwn *wwn)
2298 {
2299         struct vhost_scsi_tport *tport = container_of(wwn,
2300                                 struct vhost_scsi_tport, tport_wwn);
2301
2302         pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target"
2303                 " %s Address: %s\n", vhost_scsi_dump_proto_id(tport),
2304                 tport->tport_name);
2305
2306         kfree(tport);
2307 }
2308
2309 static ssize_t
2310 vhost_scsi_wwn_show_attr_version(struct target_fabric_configfs *tf,
2311                                 char *page)
2312 {
2313         return sprintf(page, "TCM_VHOST fabric module %s on %s/%s"
2314                 "on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
2315                 utsname()->machine);
2316 }
2317
2318 TF_WWN_ATTR_RO(vhost_scsi, version);
2319
2320 static struct configfs_attribute *vhost_scsi_wwn_attrs[] = {
2321         &vhost_scsi_wwn_version.attr,
2322         NULL,
2323 };
2324
2325 static struct target_core_fabric_ops vhost_scsi_ops = {
2326         .module                         = THIS_MODULE,
2327         .name                           = "vhost",
2328         .get_fabric_name                = vhost_scsi_get_fabric_name,
2329         .get_fabric_proto_ident         = vhost_scsi_get_fabric_proto_ident,
2330         .tpg_get_wwn                    = vhost_scsi_get_fabric_wwn,
2331         .tpg_get_tag                    = vhost_scsi_get_tpgt,
2332         .tpg_get_default_depth          = vhost_scsi_get_default_depth,
2333         .tpg_get_pr_transport_id        = vhost_scsi_get_pr_transport_id,
2334         .tpg_get_pr_transport_id_len    = vhost_scsi_get_pr_transport_id_len,
2335         .tpg_parse_pr_out_transport_id  = vhost_scsi_parse_pr_out_transport_id,
2336         .tpg_check_demo_mode            = vhost_scsi_check_true,
2337         .tpg_check_demo_mode_cache      = vhost_scsi_check_true,
2338         .tpg_check_demo_mode_write_protect = vhost_scsi_check_false,
2339         .tpg_check_prod_mode_write_protect = vhost_scsi_check_false,
2340         .tpg_check_prot_fabric_only     = vhost_scsi_check_prot_fabric_only,
2341         .tpg_alloc_fabric_acl           = vhost_scsi_alloc_fabric_acl,
2342         .tpg_release_fabric_acl         = vhost_scsi_release_fabric_acl,
2343         .tpg_get_inst_index             = vhost_scsi_tpg_get_inst_index,
2344         .release_cmd                    = vhost_scsi_release_cmd,
2345         .check_stop_free                = vhost_scsi_check_stop_free,
2346         .shutdown_session               = vhost_scsi_shutdown_session,
2347         .close_session                  = vhost_scsi_close_session,
2348         .sess_get_index                 = vhost_scsi_sess_get_index,
2349         .sess_get_initiator_sid         = NULL,
2350         .write_pending                  = vhost_scsi_write_pending,
2351         .write_pending_status           = vhost_scsi_write_pending_status,
2352         .set_default_node_attributes    = vhost_scsi_set_default_node_attrs,
2353         .get_task_tag                   = vhost_scsi_get_task_tag,
2354         .get_cmd_state                  = vhost_scsi_get_cmd_state,
2355         .queue_data_in                  = vhost_scsi_queue_data_in,
2356         .queue_status                   = vhost_scsi_queue_status,
2357         .queue_tm_rsp                   = vhost_scsi_queue_tm_rsp,
2358         .aborted_task                   = vhost_scsi_aborted_task,
2359         /*
2360          * Setup callers for generic logic in target_core_fabric_configfs.c
2361          */
2362         .fabric_make_wwn                = vhost_scsi_make_tport,
2363         .fabric_drop_wwn                = vhost_scsi_drop_tport,
2364         .fabric_make_tpg                = vhost_scsi_make_tpg,
2365         .fabric_drop_tpg                = vhost_scsi_drop_tpg,
2366         .fabric_post_link               = vhost_scsi_port_link,
2367         .fabric_pre_unlink              = vhost_scsi_port_unlink,
2368         .fabric_make_np                 = NULL,
2369         .fabric_drop_np                 = NULL,
2370         .fabric_make_nodeacl            = vhost_scsi_make_nodeacl,
2371         .fabric_drop_nodeacl            = vhost_scsi_drop_nodeacl,
2372
2373         .tfc_wwn_attrs                  = vhost_scsi_wwn_attrs,
2374         .tfc_tpg_base_attrs             = vhost_scsi_tpg_attrs,
2375         .tfc_tpg_attrib_attrs           = vhost_scsi_tpg_attrib_attrs,
2376 };
2377
2378 static int __init vhost_scsi_init(void)
2379 {
2380         int ret = -ENOMEM;
2381
2382         pr_debug("TCM_VHOST fabric module %s on %s/%s"
2383                 " on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
2384                 utsname()->machine);
2385
2386         /*
2387          * Use our own dedicated workqueue for submitting I/O into
2388          * target core to avoid contention within system_wq.
2389          */
2390         vhost_scsi_workqueue = alloc_workqueue("vhost_scsi", 0, 0);
2391         if (!vhost_scsi_workqueue)
2392                 goto out;
2393
2394         ret = vhost_scsi_register();
2395         if (ret < 0)
2396                 goto out_destroy_workqueue;
2397
2398         ret = target_register_template(&vhost_scsi_ops);
2399         if (ret < 0)
2400                 goto out_vhost_scsi_deregister;
2401
2402         return 0;
2403
2404 out_vhost_scsi_deregister:
2405         vhost_scsi_deregister();
2406 out_destroy_workqueue:
2407         destroy_workqueue(vhost_scsi_workqueue);
2408 out:
2409         return ret;
2410 };
2411
2412 static void vhost_scsi_exit(void)
2413 {
2414         target_unregister_template(&vhost_scsi_ops);
2415         vhost_scsi_deregister();
2416         destroy_workqueue(vhost_scsi_workqueue);
2417 };
2418
2419 MODULE_DESCRIPTION("VHOST_SCSI series fabric driver");
2420 MODULE_ALIAS("tcm_vhost");
2421 MODULE_LICENSE("GPL");
2422 module_init(vhost_scsi_init);
2423 module_exit(vhost_scsi_exit);