drivers/vhost/scsi.c

   1 /*******************************************************************************
   2  * Vhost kernel TCM fabric driver for virtio SCSI initiators
   3  *
   4  * (C) Copyright 2010-2012 RisingTide Systems LLC.
   5  * (C) Copyright 2010-2012 IBM Corp.
   6  *
   7  * Licensed to the Linux Foundation under the General Public License (GPL) version 2.
   8  *
   9  * Authors: Nicholas A. Bellinger <nab@risingtidesystems.com>
  10  *          Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  ****************************************************************************/
  23
  24 #include <linux/module.h>
  25 #include <linux/moduleparam.h>
  26 #include <generated/utsrelease.h>
  27 #include <linux/utsname.h>
  28 #include <linux/init.h>
  29 #include <linux/slab.h>
  30 #include <linux/kthread.h>
  31 #include <linux/types.h>
  32 #include <linux/string.h>
  33 #include <linux/configfs.h>
  34 #include <linux/ctype.h>
  35 #include <linux/compat.h>
  36 #include <linux/eventfd.h>
  37 #include <linux/fs.h>
  38 #include <linux/miscdevice.h>
  39 #include <asm/unaligned.h>
  40 #include <scsi/scsi.h>
  41 #include <scsi/scsi_tcq.h>
  42 #include <target/target_core_base.h>
  43 #include <target/target_core_fabric.h>
  44 #include <target/target_core_fabric_configfs.h>
  45 #include <target/target_core_configfs.h>
  46 #include <target/configfs_macros.h>
  47 #include <linux/vhost.h>
  48 #include <linux/virtio_scsi.h>
  49 #include <linux/llist.h>
  50 #include <linux/bitmap.h>
  51
  52 #include "vhost.c"
  53 #include "vhost.h"
  54
  55 #define TCM_VHOST_VERSION  "v0.1"
  56 #define TCM_VHOST_NAMELEN 256
  57 #define TCM_VHOST_MAX_CDB_SIZE 32
  58
  59 struct vhost_scsi_inflight {
  60         /* Wait for the flush operation to finish */
  61         struct completion comp;
  62         /* Refcount for the inflight reqs */
  63         struct kref kref;
  64 };
  65
  66 struct tcm_vhost_cmd {
  67         /* Descriptor from vhost_get_vq_desc() for virt_queue segment */
  68         int tvc_vq_desc;
  69         /* virtio-scsi initiator task attribute */
  70         int tvc_task_attr;
  71         /* virtio-scsi initiator data direction */
  72         enum dma_data_direction tvc_data_direction;
  73         /* Expected data transfer length from virtio-scsi header */
  74         u32 tvc_exp_data_len;
  75         /* The Tag from include/linux/virtio_scsi.h:struct virtio_scsi_cmd_req */
  76         u64 tvc_tag;
  77         /* The number of scatterlists associated with this cmd */
  78         u32 tvc_sgl_count;
  79         /* Saved unpacked SCSI LUN for tcm_vhost_submission_work() */
  80         u32 tvc_lun;
  81         /* Pointer to the SGL formatted memory from virtio-scsi */
  82         struct scatterlist *tvc_sgl;
  83         /* Pointer to response */
  84         struct virtio_scsi_cmd_resp __user *tvc_resp;
  85         /* Pointer to vhost_scsi for our device */
  86         struct vhost_scsi *tvc_vhost;
  87         /* Pointer to vhost_virtqueue for the cmd */
  88         struct vhost_virtqueue *tvc_vq;
  89         /* Pointer to vhost nexus memory */
  90         struct tcm_vhost_nexus *tvc_nexus;
  91         /* The TCM I/O descriptor that is accessed via container_of() */
  92         struct se_cmd tvc_se_cmd;
  93         /* work item used for cmwq dispatch to tcm_vhost_submission_work() */
  94         struct work_struct work;
  95         /* Copy of the incoming SCSI command descriptor block (CDB) */
  96         unsigned char tvc_cdb[TCM_VHOST_MAX_CDB_SIZE];
  97         /* Sense buffer that will be mapped into outgoing status */
  98         unsigned char tvc_sense_buf[TRANSPORT_SENSE_BUFFER];
  99         /* Completed commands list, serviced from vhost worker thread */
 100         struct llist_node tvc_completion_list;
 101         /* Used to track inflight cmd */
 102         struct vhost_scsi_inflight *inflight;
 103 };
 104
 105 struct tcm_vhost_nexus {
 106         /* Pointer to TCM session for I_T Nexus */
 107         struct se_session *tvn_se_sess;
 108 };
 109
 110 struct tcm_vhost_nacl {
 111         /* Binary World Wide unique Port Name for Vhost Initiator port */
 112         u64 iport_wwpn;
 113         /* ASCII formatted WWPN for Sas Initiator port */
 114         char iport_name[TCM_VHOST_NAMELEN];
 115         /* Returned by tcm_vhost_make_nodeacl() */
 116         struct se_node_acl se_node_acl;
 117 };
 118
 119 struct tcm_vhost_tpg {
 120         /* Vhost port target portal group tag for TCM */
 121         u16 tport_tpgt;
 122         /* Used to track number of TPG Port/Lun Links wrt to explict I_T Nexus shutdown */
 123         int tv_tpg_port_count;
 124         /* Used for vhost_scsi device reference to tpg_nexus, protected by tv_tpg_mutex */
 125         int tv_tpg_vhost_count;
 126         /* list for tcm_vhost_list */
 127         struct list_head tv_tpg_list;
 128         /* Used to protect access for tpg_nexus */
 129         struct mutex tv_tpg_mutex;
 130         /* Pointer to the TCM VHost I_T Nexus for this TPG endpoint */
 131         struct tcm_vhost_nexus *tpg_nexus;
 132         /* Pointer back to tcm_vhost_tport */
 133         struct tcm_vhost_tport *tport;
 134         /* Returned by tcm_vhost_make_tpg() */
 135         struct se_portal_group se_tpg;
 136         /* Pointer back to vhost_scsi, protected by tv_tpg_mutex */
 137         struct vhost_scsi *vhost_scsi;
 138 };
 139
 140 struct tcm_vhost_tport {
 141         /* SCSI protocol the tport is providing */
 142         u8 tport_proto_id;
 143         /* Binary World Wide unique Port Name for Vhost Target port */
 144         u64 tport_wwpn;
 145         /* ASCII formatted WWPN for Vhost Target port */
 146         char tport_name[TCM_VHOST_NAMELEN];
 147         /* Returned by tcm_vhost_make_tport() */
 148         struct se_wwn tport_wwn;
 149 };
 150
 151 struct tcm_vhost_evt {
 152         /* event to be sent to guest */
 153         struct virtio_scsi_event event;
 154         /* event list, serviced from vhost worker thread */
 155         struct llist_node list;
 156 };
 157
 158 enum {
 159         VHOST_SCSI_VQ_CTL = 0,
 160         VHOST_SCSI_VQ_EVT = 1,
 161         VHOST_SCSI_VQ_IO = 2,
 162 };
 163
 164 enum {
 165         VHOST_SCSI_FEATURES = VHOST_FEATURES | (1ULL << VIRTIO_SCSI_F_HOTPLUG)
 166 };
 167
 168 #define VHOST_SCSI_MAX_TARGET   256
 169 #define VHOST_SCSI_MAX_VQ       128
 170 #define VHOST_SCSI_MAX_EVENT    128
 171
 172 struct vhost_scsi_virtqueue {
 173         struct vhost_virtqueue vq;
 174         /*
 175          * Reference counting for inflight reqs, used for flush operation. At
 176          * each time, one reference tracks new commands submitted, while we
 177          * wait for another one to reach 0.
 178          */
 179         struct vhost_scsi_inflight inflights[2];
 180         /*
 181          * Indicate current inflight in use, protected by vq->mutex.
 182          * Writers must also take dev mutex and flush under it.
 183          */
 184         int inflight_idx;
 185 };
 186
 187 struct vhost_scsi {
 188         /* Protected by vhost_scsi->dev.mutex */
 189         struct tcm_vhost_tpg **vs_tpg;
 190         char vs_vhost_wwpn[TRANSPORT_IQN_LEN];
 191
 192         struct vhost_dev dev;
 193         struct vhost_scsi_virtqueue vqs[VHOST_SCSI_MAX_VQ];
 194
 195         struct vhost_work vs_completion_work; /* cmd completion work item */
 196         struct llist_head vs_completion_list; /* cmd completion queue */
 197
 198         struct vhost_work vs_event_work; /* evt injection work item */
 199         struct llist_head vs_event_list; /* evt injection queue */
 200
 201         bool vs_events_missed; /* any missed events, protected by vq->mutex */
 202         int vs_events_nr; /* num of pending events, protected by vq->mutex */
 203 };
 204
 205 /* Local pointer to allocated TCM configfs fabric module */
 206 static struct target_fabric_configfs *tcm_vhost_fabric_configfs;
 207
 208 static struct workqueue_struct *tcm_vhost_workqueue;
 209
 210 /* Global spinlock to protect tcm_vhost TPG list for vhost IOCTL access */
 211 static DEFINE_MUTEX(tcm_vhost_mutex);
 212 static LIST_HEAD(tcm_vhost_list);
 213
 214 static int iov_num_pages(struct iovec *iov)
 215 {
 216         return (PAGE_ALIGN((unsigned long)iov->iov_base + iov->iov_len) -
 217                ((unsigned long)iov->iov_base & PAGE_MASK)) >> PAGE_SHIFT;
 218 }
 219
 220 void tcm_vhost_done_inflight(struct kref *kref)
 221 {
 222         struct vhost_scsi_inflight *inflight;
 223
 224         inflight = container_of(kref, struct vhost_scsi_inflight, kref);
 225         complete(&inflight->comp);
 226 }
 227
 228 static void tcm_vhost_init_inflight(struct vhost_scsi *vs,
 229                                     struct vhost_scsi_inflight *old_inflight[])
 230 {
 231         struct vhost_scsi_inflight *new_inflight;
 232         struct vhost_virtqueue *vq;
 233         int idx, i;
 234
 235         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
 236                 vq = &vs->vqs[i].vq;
 237
 238                 mutex_lock(&vq->mutex);
 239
 240                 /* store old infight */
 241                 idx = vs->vqs[i].inflight_idx;
 242                 if (old_inflight)
 243                         old_inflight[i] = &vs->vqs[i].inflights[idx];
 244
 245                 /* setup new infight */
 246                 vs->vqs[i].inflight_idx = idx ^ 1;
 247                 new_inflight = &vs->vqs[i].inflights[idx ^ 1];
 248                 kref_init(&new_inflight->kref);
 249                 init_completion(&new_inflight->comp);
 250
 251                 mutex_unlock(&vq->mutex);
 252         }
 253 }
 254
 255 static struct vhost_scsi_inflight *
 256 tcm_vhost_get_inflight(struct vhost_virtqueue *vq)
 257 {
 258         struct vhost_scsi_inflight *inflight;
 259         struct vhost_scsi_virtqueue *svq;
 260
 261         svq = container_of(vq, struct vhost_scsi_virtqueue, vq);
 262         inflight = &svq->inflights[svq->inflight_idx];
 263         kref_get(&inflight->kref);
 264
 265         return inflight;
 266 }
 267
 268 static void tcm_vhost_put_inflight(struct vhost_scsi_inflight *inflight)
 269 {
 270         kref_put(&inflight->kref, tcm_vhost_done_inflight);
 271 }
 272
 273 static int tcm_vhost_check_true(struct se_portal_group *se_tpg)
 274 {
 275         return 1;
 276 }
 277
 278 static int tcm_vhost_check_false(struct se_portal_group *se_tpg)
 279 {
 280         return 0;
 281 }
 282
 283 static char *tcm_vhost_get_fabric_name(void)
 284 {
 285         return "vhost";
 286 }
 287
 288 static u8 tcm_vhost_get_fabric_proto_ident(struct se_portal_group *se_tpg)
 289 {
 290         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 291                                 struct tcm_vhost_tpg, se_tpg);
 292         struct tcm_vhost_tport *tport = tpg->tport;
 293
 294         switch (tport->tport_proto_id) {
 295         case SCSI_PROTOCOL_SAS:
 296                 return sas_get_fabric_proto_ident(se_tpg);
 297         case SCSI_PROTOCOL_FCP:
 298                 return fc_get_fabric_proto_ident(se_tpg);
 299         case SCSI_PROTOCOL_ISCSI:
 300                 return iscsi_get_fabric_proto_ident(se_tpg);
 301         default:
 302                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 303                         " SAS emulation\n", tport->tport_proto_id);
 304                 break;
 305         }
 306
 307         return sas_get_fabric_proto_ident(se_tpg);
 308 }
 309
 310 static char *tcm_vhost_get_fabric_wwn(struct se_portal_group *se_tpg)
 311 {
 312         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 313                                 struct tcm_vhost_tpg, se_tpg);
 314         struct tcm_vhost_tport *tport = tpg->tport;
 315
 316         return &tport->tport_name[0];
 317 }
 318
 319 static u16 tcm_vhost_get_tag(struct se_portal_group *se_tpg)
 320 {
 321         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 322                                 struct tcm_vhost_tpg, se_tpg);
 323         return tpg->tport_tpgt;
 324 }
 325
 326 static u32 tcm_vhost_get_default_depth(struct se_portal_group *se_tpg)
 327 {
 328         return 1;
 329 }
 330
 331 static u32
 332 tcm_vhost_get_pr_transport_id(struct se_portal_group *se_tpg,
 333                               struct se_node_acl *se_nacl,
 334                               struct t10_pr_registration *pr_reg,
 335                               int *format_code,
 336                               unsigned char *buf)
 337 {
 338         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 339                                 struct tcm_vhost_tpg, se_tpg);
 340         struct tcm_vhost_tport *tport = tpg->tport;
 341
 342         switch (tport->tport_proto_id) {
 343         case SCSI_PROTOCOL_SAS:
 344                 return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 345                                         format_code, buf);
 346         case SCSI_PROTOCOL_FCP:
 347                 return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 348                                         format_code, buf);
 349         case SCSI_PROTOCOL_ISCSI:
 350                 return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 351                                         format_code, buf);
 352         default:
 353                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 354                         " SAS emulation\n", tport->tport_proto_id);
 355                 break;
 356         }
 357
 358         return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 359                         format_code, buf);
 360 }
 361
 362 static u32
 363 tcm_vhost_get_pr_transport_id_len(struct se_portal_group *se_tpg,
 364                                   struct se_node_acl *se_nacl,
 365                                   struct t10_pr_registration *pr_reg,
 366                                   int *format_code)
 367 {
 368         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 369                                 struct tcm_vhost_tpg, se_tpg);
 370         struct tcm_vhost_tport *tport = tpg->tport;
 371
 372         switch (tport->tport_proto_id) {
 373         case SCSI_PROTOCOL_SAS:
 374                 return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 375                                         format_code);
 376         case SCSI_PROTOCOL_FCP:
 377                 return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 378                                         format_code);
 379         case SCSI_PROTOCOL_ISCSI:
 380                 return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 381                                         format_code);
 382         default:
 383                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 384                         " SAS emulation\n", tport->tport_proto_id);
 385                 break;
 386         }
 387
 388         return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 389                         format_code);
 390 }
 391
 392 static char *
 393 tcm_vhost_parse_pr_out_transport_id(struct se_portal_group *se_tpg,
 394                                     const char *buf,
 395                                     u32 *out_tid_len,
 396                                     char **port_nexus_ptr)
 397 {
 398         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 399                                 struct tcm_vhost_tpg, se_tpg);
 400         struct tcm_vhost_tport *tport = tpg->tport;
 401
 402         switch (tport->tport_proto_id) {
 403         case SCSI_PROTOCOL_SAS:
 404                 return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 405                                         port_nexus_ptr);
 406         case SCSI_PROTOCOL_FCP:
 407                 return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 408                                         port_nexus_ptr);
 409         case SCSI_PROTOCOL_ISCSI:
 410                 return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 411                                         port_nexus_ptr);
 412         default:
 413                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 414                         " SAS emulation\n", tport->tport_proto_id);
 415                 break;
 416         }
 417
 418         return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 419                         port_nexus_ptr);
 420 }
 421
 422 static struct se_node_acl *
 423 tcm_vhost_alloc_fabric_acl(struct se_portal_group *se_tpg)
 424 {
 425         struct tcm_vhost_nacl *nacl;
 426
 427         nacl = kzalloc(sizeof(struct tcm_vhost_nacl), GFP_KERNEL);
 428         if (!nacl) {
 429                 pr_err("Unable to allocate struct tcm_vhost_nacl\n");
 430                 return NULL;
 431         }
 432
 433         return &nacl->se_node_acl;
 434 }
 435
 436 static void
 437 tcm_vhost_release_fabric_acl(struct se_portal_group *se_tpg,
 438                              struct se_node_acl *se_nacl)
 439 {
 440         struct tcm_vhost_nacl *nacl = container_of(se_nacl,
 441                         struct tcm_vhost_nacl, se_node_acl);
 442         kfree(nacl);
 443 }
 444
 445 static u32 tcm_vhost_tpg_get_inst_index(struct se_portal_group *se_tpg)
 446 {
 447         return 1;
 448 }
 449
 450 static void tcm_vhost_release_cmd(struct se_cmd *se_cmd)
 451 {
 452         return;
 453 }
 454
 455 static int tcm_vhost_shutdown_session(struct se_session *se_sess)
 456 {
 457         return 0;
 458 }
 459
 460 static void tcm_vhost_close_session(struct se_session *se_sess)
 461 {
 462         return;
 463 }
 464
 465 static u32 tcm_vhost_sess_get_index(struct se_session *se_sess)
 466 {
 467         return 0;
 468 }
 469
 470 static int tcm_vhost_write_pending(struct se_cmd *se_cmd)
 471 {
 472         /* Go ahead and process the write immediately */
 473         target_execute_cmd(se_cmd);
 474         return 0;
 475 }
 476
 477 static int tcm_vhost_write_pending_status(struct se_cmd *se_cmd)
 478 {
 479         return 0;
 480 }
 481
 482 static void tcm_vhost_set_default_node_attrs(struct se_node_acl *nacl)
 483 {
 484         return;
 485 }
 486
 487 static u32 tcm_vhost_get_task_tag(struct se_cmd *se_cmd)
 488 {
 489         return 0;
 490 }
 491
 492 static int tcm_vhost_get_cmd_state(struct se_cmd *se_cmd)
 493 {
 494         return 0;
 495 }
 496
 497 static void vhost_scsi_complete_cmd(struct tcm_vhost_cmd *tv_cmd)
 498 {
 499         struct vhost_scsi *vs = tv_cmd->tvc_vhost;
 500
 501         llist_add(&tv_cmd->tvc_completion_list, &vs->vs_completion_list);
 502
 503         vhost_work_queue(&vs->dev, &vs->vs_completion_work);
 504 }
 505
 506 static int tcm_vhost_queue_data_in(struct se_cmd *se_cmd)
 507 {
 508         struct tcm_vhost_cmd *tv_cmd = container_of(se_cmd,
 509                                 struct tcm_vhost_cmd, tvc_se_cmd);
 510         vhost_scsi_complete_cmd(tv_cmd);
 511         return 0;
 512 }
 513
 514 static int tcm_vhost_queue_status(struct se_cmd *se_cmd)
 515 {
 516         struct tcm_vhost_cmd *tv_cmd = container_of(se_cmd,
 517                                 struct tcm_vhost_cmd, tvc_se_cmd);
 518         vhost_scsi_complete_cmd(tv_cmd);
 519         return 0;
 520 }
 521
 522 static int tcm_vhost_queue_tm_rsp(struct se_cmd *se_cmd)
 523 {
 524         return 0;
 525 }
 526
 527 static void tcm_vhost_free_evt(struct vhost_scsi *vs, struct tcm_vhost_evt *evt)
 528 {
 529         vs->vs_events_nr--;
 530         kfree(evt);
 531 }
 532
 533 static struct tcm_vhost_evt *
 534 tcm_vhost_allocate_evt(struct vhost_scsi *vs,
 535                        u32 event, u32 reason)
 536 {
 537         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 538         struct tcm_vhost_evt *evt;
 539
 540         if (vs->vs_events_nr > VHOST_SCSI_MAX_EVENT) {
 541                 vs->vs_events_missed = true;
 542                 return NULL;
 543         }
 544
 545         evt = kzalloc(sizeof(*evt), GFP_KERNEL);
 546         if (!evt) {
 547                 vq_err(vq, "Failed to allocate tcm_vhost_evt\n");
 548                 vs->vs_events_missed = true;
 549                 return NULL;
 550         }
 551
 552         evt->event.event = event;
 553         evt->event.reason = reason;
 554         vs->vs_events_nr++;
 555
 556         return evt;
 557 }
 558
 559 static void vhost_scsi_free_cmd(struct tcm_vhost_cmd *tv_cmd)
 560 {
 561         struct se_cmd *se_cmd = &tv_cmd->tvc_se_cmd;
 562
 563         /* TODO locking against target/backend threads? */
 564         transport_generic_free_cmd(se_cmd, 1);
 565
 566         if (tv_cmd->tvc_sgl_count) {
 567                 u32 i;
 568                 for (i = 0; i < tv_cmd->tvc_sgl_count; i++)
 569                         put_page(sg_page(&tv_cmd->tvc_sgl[i]));
 570
 571                 kfree(tv_cmd->tvc_sgl);
 572         }
 573
 574         tcm_vhost_put_inflight(tv_cmd->inflight);
 575
 576         kfree(tv_cmd);
 577 }
 578
 579 static void
 580 tcm_vhost_do_evt_work(struct vhost_scsi *vs, struct tcm_vhost_evt *evt)
 581 {
 582         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 583         struct virtio_scsi_event *event = &evt->event;
 584         struct virtio_scsi_event __user *eventp;
 585         unsigned out, in;
 586         int head, ret;
 587
 588         if (!vq->private_data) {
 589                 vs->vs_events_missed = true;
 590                 return;
 591         }
 592
 593 again:
 594         vhost_disable_notify(&vs->dev, vq);
 595         head = vhost_get_vq_desc(&vs->dev, vq, vq->iov,
 596                         ARRAY_SIZE(vq->iov), &out, &in,
 597                         NULL, NULL);
 598         if (head < 0) {
 599                 vs->vs_events_missed = true;
 600                 return;
 601         }
 602         if (head == vq->num) {
 603                 if (vhost_enable_notify(&vs->dev, vq))
 604                         goto again;
 605                 vs->vs_events_missed = true;
 606                 return;
 607         }
 608
 609         if ((vq->iov[out].iov_len != sizeof(struct virtio_scsi_event))) {
 610                 vq_err(vq, "Expecting virtio_scsi_event, got %zu bytes\n",
 611                                 vq->iov[out].iov_len);
 612                 vs->vs_events_missed = true;
 613                 return;
 614         }
 615
 616         if (vs->vs_events_missed) {
 617                 event->event |= VIRTIO_SCSI_T_EVENTS_MISSED;
 618                 vs->vs_events_missed = false;
 619         }
 620
 621         eventp = vq->iov[out].iov_base;
 622         ret = __copy_to_user(eventp, event, sizeof(*event));
 623         if (!ret)
 624                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 625         else
 626                 vq_err(vq, "Faulted on tcm_vhost_send_event\n");
 627 }
 628
 629 static void tcm_vhost_evt_work(struct vhost_work *work)
 630 {
 631         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 632                                         vs_event_work);
 633         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 634         struct tcm_vhost_evt *evt;
 635         struct llist_node *llnode;
 636
 637         mutex_lock(&vq->mutex);
 638         llnode = llist_del_all(&vs->vs_event_list);
 639         while (llnode) {
 640                 evt = llist_entry(llnode, struct tcm_vhost_evt, list);
 641                 llnode = llist_next(llnode);
 642                 tcm_vhost_do_evt_work(vs, evt);
 643                 tcm_vhost_free_evt(vs, evt);
 644         }
 645         mutex_unlock(&vq->mutex);
 646 }
 647
 648 /* Fill in status and signal that we are done processing this command
 649  *
 650  * This is scheduled in the vhost work queue so we are called with the owner
 651  * process mm and can access the vring.
 652  */
 653 static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
 654 {
 655         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 656                                         vs_completion_work);
 657         DECLARE_BITMAP(signal, VHOST_SCSI_MAX_VQ);
 658         struct virtio_scsi_cmd_resp v_rsp;
 659         struct tcm_vhost_cmd *tv_cmd;
 660         struct llist_node *llnode;
 661         struct se_cmd *se_cmd;
 662         int ret, vq;
 663
 664         bitmap_zero(signal, VHOST_SCSI_MAX_VQ);
 665         llnode = llist_del_all(&vs->vs_completion_list);
 666         while (llnode) {
 667                 tv_cmd = llist_entry(llnode, struct tcm_vhost_cmd,
 668                                      tvc_completion_list);
 669                 llnode = llist_next(llnode);
 670                 se_cmd = &tv_cmd->tvc_se_cmd;
 671
 672                 pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__,
 673                         tv_cmd, se_cmd->residual_count, se_cmd->scsi_status);
 674
 675                 memset(&v_rsp, 0, sizeof(v_rsp));
 676                 v_rsp.resid = se_cmd->residual_count;
 677                 /* TODO is status_qualifier field needed? */
 678                 v_rsp.status = se_cmd->scsi_status;
 679                 v_rsp.sense_len = se_cmd->scsi_sense_length;
 680                 memcpy(v_rsp.sense, tv_cmd->tvc_sense_buf,
 681                        v_rsp.sense_len);
 682                 ret = copy_to_user(tv_cmd->tvc_resp, &v_rsp, sizeof(v_rsp));
 683                 if (likely(ret == 0)) {
 684                         struct vhost_scsi_virtqueue *q;
 685                         vhost_add_used(tv_cmd->tvc_vq, tv_cmd->tvc_vq_desc, 0);
 686                         q = container_of(tv_cmd->tvc_vq, struct vhost_scsi_virtqueue, vq);
 687                         vq = q - vs->vqs;
 688                         __set_bit(vq, signal);
 689                 } else
 690                         pr_err("Faulted on virtio_scsi_cmd_resp\n");
 691
 692                 vhost_scsi_free_cmd(tv_cmd);
 693         }
 694
 695         vq = -1;
 696         while ((vq = find_next_bit(signal, VHOST_SCSI_MAX_VQ, vq + 1))
 697                 < VHOST_SCSI_MAX_VQ)
 698                 vhost_signal(&vs->dev, &vs->vqs[vq].vq);
 699 }
 700
 701 static struct tcm_vhost_cmd *
 702 vhost_scsi_allocate_cmd(struct vhost_virtqueue *vq,
 703                         struct tcm_vhost_tpg *tpg,
 704                         struct virtio_scsi_cmd_req *v_req,
 705                         u32 exp_data_len,
 706                         int data_direction)
 707 {
 708         struct tcm_vhost_cmd *tv_cmd;
 709         struct tcm_vhost_nexus *tv_nexus;
 710
 711         tv_nexus = tpg->tpg_nexus;
 712         if (!tv_nexus) {
 713                 pr_err("Unable to locate active struct tcm_vhost_nexus\n");
 714                 return ERR_PTR(-EIO);
 715         }
 716
 717         tv_cmd = kzalloc(sizeof(struct tcm_vhost_cmd), GFP_ATOMIC);
 718         if (!tv_cmd) {
 719                 pr_err("Unable to allocate struct tcm_vhost_cmd\n");
 720                 return ERR_PTR(-ENOMEM);
 721         }
 722         tv_cmd->tvc_tag = v_req->tag;
 723         tv_cmd->tvc_task_attr = v_req->task_attr;
 724         tv_cmd->tvc_exp_data_len = exp_data_len;
 725         tv_cmd->tvc_data_direction = data_direction;
 726         tv_cmd->tvc_nexus = tv_nexus;
 727         tv_cmd->inflight = tcm_vhost_get_inflight(vq);
 728
 729         return tv_cmd;
 730 }
 731
 732 /*
 733  * Map a user memory range into a scatterlist
 734  *
 735  * Returns the number of scatterlist entries used or -errno on error.
 736  */
 737 static int
 738 vhost_scsi_map_to_sgl(struct scatterlist *sgl,
 739                       unsigned int sgl_count,
 740                       struct iovec *iov,
 741                       int write)
 742 {
 743         unsigned int npages = 0, pages_nr, offset, nbytes;
 744         struct scatterlist *sg = sgl;
 745         void __user *ptr = iov->iov_base;
 746         size_t len = iov->iov_len;
 747         struct page **pages;
 748         int ret, i;
 749
 750         pages_nr = iov_num_pages(iov);
 751         if (pages_nr > sgl_count)
 752                 return -ENOBUFS;
 753
 754         pages = kmalloc(pages_nr * sizeof(struct page *), GFP_KERNEL);
 755         if (!pages)
 756                 return -ENOMEM;
 757
 758         ret = get_user_pages_fast((unsigned long)ptr, pages_nr, write, pages);
 759         /* No pages were pinned */
 760         if (ret < 0)
 761                 goto out;
 762         /* Less pages pinned than wanted */
 763         if (ret != pages_nr) {
 764                 for (i = 0; i < ret; i++)
 765                         put_page(pages[i]);
 766                 ret = -EFAULT;
 767                 goto out;
 768         }
 769
 770         while (len > 0) {
 771                 offset = (uintptr_t)ptr & ~PAGE_MASK;
 772                 nbytes = min_t(unsigned int, PAGE_SIZE - offset, len);
 773                 sg_set_page(sg, pages[npages], nbytes, offset);
 774                 ptr += nbytes;
 775                 len -= nbytes;
 776                 sg++;
 777                 npages++;
 778         }
 779
 780 out:
 781         kfree(pages);
 782         return ret;
 783 }
 784
 785 static int
 786 vhost_scsi_map_iov_to_sgl(struct tcm_vhost_cmd *tv_cmd,
 787                           struct iovec *iov,
 788                           unsigned int niov,
 789                           int write)
 790 {
 791         int ret;
 792         unsigned int i;
 793         u32 sgl_count;
 794         struct scatterlist *sg;
 795
 796         /*
 797          * Find out how long sglist needs to be
 798          */
 799         sgl_count = 0;
 800         for (i = 0; i < niov; i++)
 801                 sgl_count += iov_num_pages(&iov[i]);
 802
 803         /* TODO overflow checking */
 804
 805         sg = kmalloc(sizeof(tv_cmd->tvc_sgl[0]) * sgl_count, GFP_ATOMIC);
 806         if (!sg)
 807                 return -ENOMEM;
 808         pr_debug("%s sg %p sgl_count %u is_err %d\n", __func__,
 809                sg, sgl_count, !sg);
 810         sg_init_table(sg, sgl_count);
 811
 812         tv_cmd->tvc_sgl = sg;
 813         tv_cmd->tvc_sgl_count = sgl_count;
 814
 815         pr_debug("Mapping %u iovecs for %u pages\n", niov, sgl_count);
 816         for (i = 0; i < niov; i++) {
 817                 ret = vhost_scsi_map_to_sgl(sg, sgl_count, &iov[i], write);
 818                 if (ret < 0) {
 819                         for (i = 0; i < tv_cmd->tvc_sgl_count; i++)
 820                                 put_page(sg_page(&tv_cmd->tvc_sgl[i]));
 821                         kfree(tv_cmd->tvc_sgl);
 822                         tv_cmd->tvc_sgl = NULL;
 823                         tv_cmd->tvc_sgl_count = 0;
 824                         return ret;
 825                 }
 826
 827                 sg += ret;
 828                 sgl_count -= ret;
 829         }
 830         return 0;
 831 }
 832
 833 static void tcm_vhost_submission_work(struct work_struct *work)
 834 {
 835         struct tcm_vhost_cmd *tv_cmd =
 836                 container_of(work, struct tcm_vhost_cmd, work);
 837         struct tcm_vhost_nexus *tv_nexus;
 838         struct se_cmd *se_cmd = &tv_cmd->tvc_se_cmd;
 839         struct scatterlist *sg_ptr, *sg_bidi_ptr = NULL;
 840         int rc, sg_no_bidi = 0;
 841
 842         if (tv_cmd->tvc_sgl_count) {
 843                 sg_ptr = tv_cmd->tvc_sgl;
 844 /* FIXME: Fix BIDI operation in tcm_vhost_submission_work() */
 845 #if 0
 846                 if (se_cmd->se_cmd_flags & SCF_BIDI) {
 847                         sg_bidi_ptr = NULL;
 848                         sg_no_bidi = 0;
 849                 }
 850 #endif
 851         } else {
 852                 sg_ptr = NULL;
 853         }
 854         tv_nexus = tv_cmd->tvc_nexus;
 855
 856         rc = target_submit_cmd_map_sgls(se_cmd, tv_nexus->tvn_se_sess,
 857                         tv_cmd->tvc_cdb, &tv_cmd->tvc_sense_buf[0],
 858                         tv_cmd->tvc_lun, tv_cmd->tvc_exp_data_len,
 859                         tv_cmd->tvc_task_attr, tv_cmd->tvc_data_direction,
 860                         0, sg_ptr, tv_cmd->tvc_sgl_count,
 861                         sg_bidi_ptr, sg_no_bidi);
 862         if (rc < 0) {
 863                 transport_send_check_condition_and_sense(se_cmd,
 864                                 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
 865                 transport_generic_free_cmd(se_cmd, 0);
 866         }
 867 }
 868
 869 static void
 870 vhost_scsi_send_bad_target(struct vhost_scsi *vs,
 871                            struct vhost_virtqueue *vq,
 872                            int head, unsigned out)
 873 {
 874         struct virtio_scsi_cmd_resp __user *resp;
 875         struct virtio_scsi_cmd_resp rsp;
 876         int ret;
 877
 878         memset(&rsp, 0, sizeof(rsp));
 879         rsp.response = VIRTIO_SCSI_S_BAD_TARGET;
 880         resp = vq->iov[out].iov_base;
 881         ret = __copy_to_user(resp, &rsp, sizeof(rsp));
 882         if (!ret)
 883                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 884         else
 885                 pr_err("Faulted on virtio_scsi_cmd_resp\n");
 886 }
 887
 888 static void
 889 vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
 890 {
 891         struct tcm_vhost_tpg **vs_tpg;
 892         struct virtio_scsi_cmd_req v_req;
 893         struct tcm_vhost_tpg *tpg;
 894         struct tcm_vhost_cmd *tv_cmd;
 895         u32 exp_data_len, data_first, data_num, data_direction;
 896         unsigned out, in, i;
 897         int head, ret;
 898         u8 target;
 899
 900         /*
 901          * We can handle the vq only after the endpoint is setup by calling the
 902          * VHOST_SCSI_SET_ENDPOINT ioctl.
 903          *
 904          * TODO: Check that we are running from vhost_worker which acts
 905          * as read-side critical section for vhost kind of RCU.
 906          * See the comments in struct vhost_virtqueue in drivers/vhost/vhost.h
 907          */
 908         vs_tpg = rcu_dereference_check(vq->private_data, 1);
 909         if (!vs_tpg)
 910                 return;
 911
 912         mutex_lock(&vq->mutex);
 913         vhost_disable_notify(&vs->dev, vq);
 914
 915         for (;;) {
 916                 head = vhost_get_vq_desc(&vs->dev, vq, vq->iov,
 917                                         ARRAY_SIZE(vq->iov), &out, &in,
 918                                         NULL, NULL);
 919                 pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n",
 920                                         head, out, in);
 921                 /* On error, stop handling until the next kick. */
 922                 if (unlikely(head < 0))
 923                         break;
 924                 /* Nothing new?  Wait for eventfd to tell us they refilled. */
 925                 if (head == vq->num) {
 926                         if (unlikely(vhost_enable_notify(&vs->dev, vq))) {
 927                                 vhost_disable_notify(&vs->dev, vq);
 928                                 continue;
 929                         }
 930                         break;
 931                 }
 932
 933 /* FIXME: BIDI operation */
 934                 if (out == 1 && in == 1) {
 935                         data_direction = DMA_NONE;
 936                         data_first = 0;
 937                         data_num = 0;
 938                 } else if (out == 1 && in > 1) {
 939                         data_direction = DMA_FROM_DEVICE;
 940                         data_first = out + 1;
 941                         data_num = in - 1;
 942                 } else if (out > 1 && in == 1) {
 943                         data_direction = DMA_TO_DEVICE;
 944                         data_first = 1;
 945                         data_num = out - 1;
 946                 } else {
 947                         vq_err(vq, "Invalid buffer layout out: %u in: %u\n",
 948                                         out, in);
 949                         break;
 950                 }
 951
 952                 /*
 953                  * Check for a sane resp buffer so we can report errors to
 954                  * the guest.
 955                  */
 956                 if (unlikely(vq->iov[out].iov_len !=
 957                                         sizeof(struct virtio_scsi_cmd_resp))) {
 958                         vq_err(vq, "Expecting virtio_scsi_cmd_resp, got %zu"
 959                                 " bytes\n", vq->iov[out].iov_len);
 960                         break;
 961                 }
 962
 963                 if (unlikely(vq->iov[0].iov_len != sizeof(v_req))) {
 964                         vq_err(vq, "Expecting virtio_scsi_cmd_req, got %zu"
 965                                 " bytes\n", vq->iov[0].iov_len);
 966                         break;
 967                 }
 968                 pr_debug("Calling __copy_from_user: vq->iov[0].iov_base: %p,"
 969                         " len: %zu\n", vq->iov[0].iov_base, sizeof(v_req));
 970                 ret = __copy_from_user(&v_req, vq->iov[0].iov_base,
 971                                 sizeof(v_req));
 972                 if (unlikely(ret)) {
 973                         vq_err(vq, "Faulted on virtio_scsi_cmd_req\n");
 974                         break;
 975                 }
 976
 977                 /* Extract the tpgt */
 978                 target = v_req.lun[1];
 979                 tpg = ACCESS_ONCE(vs_tpg[target]);
 980
 981                 /* Target does not exist, fail the request */
 982                 if (unlikely(!tpg)) {
 983                         vhost_scsi_send_bad_target(vs, vq, head, out);
 984                         continue;
 985                 }
 986
 987                 exp_data_len = 0;
 988                 for (i = 0; i < data_num; i++)
 989                         exp_data_len += vq->iov[data_first + i].iov_len;
 990
 991                 tv_cmd = vhost_scsi_allocate_cmd(vq, tpg, &v_req,
 992                                         exp_data_len, data_direction);
 993                 if (IS_ERR(tv_cmd)) {
 994                         vq_err(vq, "vhost_scsi_allocate_cmd failed %ld\n",
 995                                         PTR_ERR(tv_cmd));
 996                         goto err_cmd;
 997                 }
 998                 pr_debug("Allocated tv_cmd: %p exp_data_len: %d, data_direction"
 999                         ": %d\n", tv_cmd, exp_data_len, data_direction);
1000
1001                 tv_cmd->tvc_vhost = vs;
1002                 tv_cmd->tvc_vq = vq;
1003                 tv_cmd->tvc_resp = vq->iov[out].iov_base;
1004
1005                 /*
1006                  * Copy in the recieved CDB descriptor into tv_cmd->tvc_cdb
1007                  * that will be used by tcm_vhost_new_cmd_map() and down into
1008                  * target_setup_cmd_from_cdb()
1009                  */
1010                 memcpy(tv_cmd->tvc_cdb, v_req.cdb, TCM_VHOST_MAX_CDB_SIZE);
1011                 /*
1012                  * Check that the recieved CDB size does not exceeded our
1013                  * hardcoded max for tcm_vhost
1014                  */
1015                 /* TODO what if cdb was too small for varlen cdb header? */
1016                 if (unlikely(scsi_command_size(tv_cmd->tvc_cdb) >
1017                                         TCM_VHOST_MAX_CDB_SIZE)) {
1018                         vq_err(vq, "Received SCSI CDB with command_size: %d that"
1019                                 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1020                                 scsi_command_size(tv_cmd->tvc_cdb),
1021                                 TCM_VHOST_MAX_CDB_SIZE);
1022                         goto err_free;
1023                 }
1024                 tv_cmd->tvc_lun = ((v_req.lun[2] << 8) | v_req.lun[3]) & 0x3FFF;
1025
1026                 pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n",
1027                         tv_cmd->tvc_cdb[0], tv_cmd->tvc_lun);
1028
1029                 if (data_direction != DMA_NONE) {
1030                         ret = vhost_scsi_map_iov_to_sgl(tv_cmd,
1031                                         &vq->iov[data_first], data_num,
1032                                         data_direction == DMA_TO_DEVICE);
1033                         if (unlikely(ret)) {
1034                                 vq_err(vq, "Failed to map iov to sgl\n");
1035                                 goto err_free;
1036                         }
1037                 }
1038
1039                 /*
1040                  * Save the descriptor from vhost_get_vq_desc() to be used to
1041                  * complete the virtio-scsi request in TCM callback context via
1042                  * tcm_vhost_queue_data_in() and tcm_vhost_queue_status()
1043                  */
1044                 tv_cmd->tvc_vq_desc = head;
1045                 /*
1046                  * Dispatch tv_cmd descriptor for cmwq execution in process
1047                  * context provided by tcm_vhost_workqueue.  This also ensures
1048                  * tv_cmd is executed on the same kworker CPU as this vhost
1049                  * thread to gain positive L2 cache locality effects..
1050                  */
1051                 INIT_WORK(&tv_cmd->work, tcm_vhost_submission_work);
1052                 queue_work(tcm_vhost_workqueue, &tv_cmd->work);
1053         }
1054
1055         mutex_unlock(&vq->mutex);
1056         return;
1057
1058 err_free:
1059         vhost_scsi_free_cmd(tv_cmd);
1060 err_cmd:
1061         vhost_scsi_send_bad_target(vs, vq, head, out);
1062         mutex_unlock(&vq->mutex);
1063 }
1064
1065 static void vhost_scsi_ctl_handle_kick(struct vhost_work *work)
1066 {
1067         pr_debug("%s: The handling func for control queue.\n", __func__);
1068 }
1069
1070 static void
1071 tcm_vhost_send_evt(struct vhost_scsi *vs,
1072                    struct tcm_vhost_tpg *tpg,
1073                    struct se_lun *lun,
1074                    u32 event,
1075                    u32 reason)
1076 {
1077         struct tcm_vhost_evt *evt;
1078
1079         evt = tcm_vhost_allocate_evt(vs, event, reason);
1080         if (!evt)
1081                 return;
1082
1083         if (tpg && lun) {
1084                 /* TODO: share lun setup code with virtio-scsi.ko */
1085                 /*
1086                  * Note: evt->event is zeroed when we allocate it and
1087                  * lun[4-7] need to be zero according to virtio-scsi spec.
1088                  */
1089                 evt->event.lun[0] = 0x01;
1090                 evt->event.lun[1] = tpg->tport_tpgt & 0xFF;
1091                 if (lun->unpacked_lun >= 256)
1092                         evt->event.lun[2] = lun->unpacked_lun >> 8 | 0x40 ;
1093                 evt->event.lun[3] = lun->unpacked_lun & 0xFF;
1094         }
1095
1096         llist_add(&evt->list, &vs->vs_event_list);
1097         vhost_work_queue(&vs->dev, &vs->vs_event_work);
1098 }
1099
1100 static void vhost_scsi_evt_handle_kick(struct vhost_work *work)
1101 {
1102         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1103                                                 poll.work);
1104         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1105
1106         mutex_lock(&vq->mutex);
1107         if (!vq->private_data)
1108                 goto out;
1109
1110         if (vs->vs_events_missed)
1111                 tcm_vhost_send_evt(vs, NULL, NULL, VIRTIO_SCSI_T_NO_EVENT, 0);
1112 out:
1113         mutex_unlock(&vq->mutex);
1114 }
1115
1116 static void vhost_scsi_handle_kick(struct vhost_work *work)
1117 {
1118         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1119                                                 poll.work);
1120         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1121
1122         vhost_scsi_handle_vq(vs, vq);
1123 }
1124
1125 static void vhost_scsi_flush_vq(struct vhost_scsi *vs, int index)
1126 {
1127         vhost_poll_flush(&vs->vqs[index].vq.poll);
1128 }
1129
1130 /* Callers must hold dev mutex */
1131 static void vhost_scsi_flush(struct vhost_scsi *vs)
1132 {
1133         struct vhost_scsi_inflight *old_inflight[VHOST_SCSI_MAX_VQ];
1134         int i;
1135
1136         /* Init new inflight and remember the old inflight */
1137         tcm_vhost_init_inflight(vs, old_inflight);
1138
1139         /*
1140          * The inflight->kref was initialized to 1. We decrement it here to
1141          * indicate the start of the flush operation so that it will reach 0
1142          * when all the reqs are finished.
1143          */
1144         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1145                 kref_put(&old_inflight[i]->kref, tcm_vhost_done_inflight);
1146
1147         /* Flush both the vhost poll and vhost work */
1148         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1149                 vhost_scsi_flush_vq(vs, i);
1150         vhost_work_flush(&vs->dev, &vs->vs_completion_work);
1151         vhost_work_flush(&vs->dev, &vs->vs_event_work);
1152
1153         /* Wait for all reqs issued before the flush to be finished */
1154         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1155                 wait_for_completion(&old_inflight[i]->comp);
1156 }
1157
1158 /*
1159  * Called from vhost_scsi_ioctl() context to walk the list of available
1160  * tcm_vhost_tpg with an active struct tcm_vhost_nexus
1161  *
1162  *  The lock nesting rule is:
1163  *    tcm_vhost_mutex -> vs->dev.mutex -> tpg->tv_tpg_mutex -> vq->mutex
1164  */
1165 static int
1166 vhost_scsi_set_endpoint(struct vhost_scsi *vs,
1167                         struct vhost_scsi_target *t)
1168 {
1169         struct tcm_vhost_tport *tv_tport;
1170         struct tcm_vhost_tpg *tpg;
1171         struct tcm_vhost_tpg **vs_tpg;
1172         struct vhost_virtqueue *vq;
1173         int index, ret, i, len;
1174         bool match = false;
1175
1176         mutex_lock(&tcm_vhost_mutex);
1177         mutex_lock(&vs->dev.mutex);
1178
1179         /* Verify that ring has been setup correctly. */
1180         for (index = 0; index < vs->dev.nvqs; ++index) {
1181                 /* Verify that ring has been setup correctly. */
1182                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1183                         ret = -EFAULT;
1184                         goto out;
1185                 }
1186         }
1187
1188         len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET;
1189         vs_tpg = kzalloc(len, GFP_KERNEL);
1190         if (!vs_tpg) {
1191                 ret = -ENOMEM;
1192                 goto out;
1193         }
1194         if (vs->vs_tpg)
1195                 memcpy(vs_tpg, vs->vs_tpg, len);
1196
1197         list_for_each_entry(tpg, &tcm_vhost_list, tv_tpg_list) {
1198                 mutex_lock(&tpg->tv_tpg_mutex);
1199                 if (!tpg->tpg_nexus) {
1200                         mutex_unlock(&tpg->tv_tpg_mutex);
1201                         continue;
1202                 }
1203                 if (tpg->tv_tpg_vhost_count != 0) {
1204                         mutex_unlock(&tpg->tv_tpg_mutex);
1205                         continue;
1206                 }
1207                 tv_tport = tpg->tport;
1208
1209                 if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1210                         if (vs->vs_tpg && vs->vs_tpg[tpg->tport_tpgt]) {
1211                                 kfree(vs_tpg);
1212                                 mutex_unlock(&tpg->tv_tpg_mutex);
1213                                 ret = -EEXIST;
1214                                 goto out;
1215                         }
1216                         tpg->tv_tpg_vhost_count++;
1217                         tpg->vhost_scsi = vs;
1218                         vs_tpg[tpg->tport_tpgt] = tpg;
1219                         smp_mb__after_atomic_inc();
1220                         match = true;
1221                 }
1222                 mutex_unlock(&tpg->tv_tpg_mutex);
1223         }
1224
1225         if (match) {
1226                 memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
1227                        sizeof(vs->vs_vhost_wwpn));
1228                 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1229                         vq = &vs->vqs[i].vq;
1230                         /* Flushing the vhost_work acts as synchronize_rcu */
1231                         mutex_lock(&vq->mutex);
1232                         rcu_assign_pointer(vq->private_data, vs_tpg);
1233                         vhost_init_used(vq);
1234                         mutex_unlock(&vq->mutex);
1235                 }
1236                 ret = 0;
1237         } else {
1238                 ret = -EEXIST;
1239         }
1240
1241         /*
1242          * Act as synchronize_rcu to make sure access to
1243          * old vs->vs_tpg is finished.
1244          */
1245         vhost_scsi_flush(vs);
1246         kfree(vs->vs_tpg);
1247         vs->vs_tpg = vs_tpg;
1248
1249 out:
1250         mutex_unlock(&vs->dev.mutex);
1251         mutex_unlock(&tcm_vhost_mutex);
1252         return ret;
1253 }
1254
1255 static int
1256 vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
1257                           struct vhost_scsi_target *t)
1258 {
1259         struct tcm_vhost_tport *tv_tport;
1260         struct tcm_vhost_tpg *tpg;
1261         struct vhost_virtqueue *vq;
1262         bool match = false;
1263         int index, ret, i;
1264         u8 target;
1265
1266         mutex_lock(&tcm_vhost_mutex);
1267         mutex_lock(&vs->dev.mutex);
1268         /* Verify that ring has been setup correctly. */
1269         for (index = 0; index < vs->dev.nvqs; ++index) {
1270                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1271                         ret = -EFAULT;
1272                         goto err_dev;
1273                 }
1274         }
1275
1276         if (!vs->vs_tpg) {
1277                 ret = 0;
1278                 goto err_dev;
1279         }
1280
1281         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1282                 target = i;
1283                 tpg = vs->vs_tpg[target];
1284                 if (!tpg)
1285                         continue;
1286
1287                 mutex_lock(&tpg->tv_tpg_mutex);
1288                 tv_tport = tpg->tport;
1289                 if (!tv_tport) {
1290                         ret = -ENODEV;
1291                         goto err_tpg;
1292                 }
1293
1294                 if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1295                         pr_warn("tv_tport->tport_name: %s, tpg->tport_tpgt: %hu"
1296                                 " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
1297                                 tv_tport->tport_name, tpg->tport_tpgt,
1298                                 t->vhost_wwpn, t->vhost_tpgt);
1299                         ret = -EINVAL;
1300                         goto err_tpg;
1301                 }
1302                 tpg->tv_tpg_vhost_count--;
1303                 tpg->vhost_scsi = NULL;
1304                 vs->vs_tpg[target] = NULL;
1305                 match = true;
1306                 mutex_unlock(&tpg->tv_tpg_mutex);
1307         }
1308         if (match) {
1309                 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1310                         vq = &vs->vqs[i].vq;
1311                         /* Flushing the vhost_work acts as synchronize_rcu */
1312                         mutex_lock(&vq->mutex);
1313                         rcu_assign_pointer(vq->private_data, NULL);
1314                         mutex_unlock(&vq->mutex);
1315                 }
1316         }
1317         /*
1318          * Act as synchronize_rcu to make sure access to
1319          * old vs->vs_tpg is finished.
1320          */
1321         vhost_scsi_flush(vs);
1322         kfree(vs->vs_tpg);
1323         vs->vs_tpg = NULL;
1324         WARN_ON(vs->vs_events_nr);
1325         mutex_unlock(&vs->dev.mutex);
1326         mutex_unlock(&tcm_vhost_mutex);
1327         return 0;
1328
1329 err_tpg:
1330         mutex_unlock(&tpg->tv_tpg_mutex);
1331 err_dev:
1332         mutex_unlock(&vs->dev.mutex);
1333         mutex_unlock(&tcm_vhost_mutex);
1334         return ret;
1335 }
1336
1337 static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features)
1338 {
1339         if (features & ~VHOST_SCSI_FEATURES)
1340                 return -EOPNOTSUPP;
1341
1342         mutex_lock(&vs->dev.mutex);
1343         if ((features & (1 << VHOST_F_LOG_ALL)) &&
1344             !vhost_log_access_ok(&vs->dev)) {
1345                 mutex_unlock(&vs->dev.mutex);
1346                 return -EFAULT;
1347         }
1348         vs->dev.acked_features = features;
1349         smp_wmb();
1350         vhost_scsi_flush(vs);
1351         mutex_unlock(&vs->dev.mutex);
1352         return 0;
1353 }
1354
1355 static int vhost_scsi_open(struct inode *inode, struct file *f)
1356 {
1357         struct vhost_scsi *vs;
1358         struct vhost_virtqueue **vqs;
1359         int r, i;
1360
1361         vs = kzalloc(sizeof(*vs), GFP_KERNEL);
1362         if (!vs)
1363                 return -ENOMEM;
1364
1365         vqs = kmalloc(VHOST_SCSI_MAX_VQ * sizeof(*vqs), GFP_KERNEL);
1366         if (!vqs) {
1367                 kfree(vs);
1368                 return -ENOMEM;
1369         }
1370
1371         vhost_work_init(&vs->vs_completion_work, vhost_scsi_complete_cmd_work);
1372         vhost_work_init(&vs->vs_event_work, tcm_vhost_evt_work);
1373
1374         vs->vs_events_nr = 0;
1375         vs->vs_events_missed = false;
1376
1377         vqs[VHOST_SCSI_VQ_CTL] = &vs->vqs[VHOST_SCSI_VQ_CTL].vq;
1378         vqs[VHOST_SCSI_VQ_EVT] = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1379         vs->vqs[VHOST_SCSI_VQ_CTL].vq.handle_kick = vhost_scsi_ctl_handle_kick;
1380         vs->vqs[VHOST_SCSI_VQ_EVT].vq.handle_kick = vhost_scsi_evt_handle_kick;
1381         for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++) {
1382                 vqs[i] = &vs->vqs[i].vq;
1383                 vs->vqs[i].vq.handle_kick = vhost_scsi_handle_kick;
1384         }
1385         r = vhost_dev_init(&vs->dev, vqs, VHOST_SCSI_MAX_VQ);
1386
1387         tcm_vhost_init_inflight(vs, NULL);
1388
1389         if (r < 0) {
1390                 kfree(vqs);
1391                 kfree(vs);
1392                 return r;
1393         }
1394
1395         f->private_data = vs;
1396         return 0;
1397 }
1398
1399 static int vhost_scsi_release(struct inode *inode, struct file *f)
1400 {
1401         struct vhost_scsi *vs = f->private_data;
1402         struct vhost_scsi_target t;
1403
1404         mutex_lock(&vs->dev.mutex);
1405         memcpy(t.vhost_wwpn, vs->vs_vhost_wwpn, sizeof(t.vhost_wwpn));
1406         mutex_unlock(&vs->dev.mutex);
1407         vhost_scsi_clear_endpoint(vs, &t);
1408         vhost_dev_stop(&vs->dev);
1409         vhost_dev_cleanup(&vs->dev, false);
1410         /* Jobs can re-queue themselves in evt kick handler. Do extra flush. */
1411         vhost_scsi_flush(vs);
1412         kfree(vs->dev.vqs);
1413         kfree(vs);
1414         return 0;
1415 }
1416
1417 static long
1418 vhost_scsi_ioctl(struct file *f,
1419                  unsigned int ioctl,
1420                  unsigned long arg)
1421 {
1422         struct vhost_scsi *vs = f->private_data;
1423         struct vhost_scsi_target backend;
1424         void __user *argp = (void __user *)arg;
1425         u64 __user *featurep = argp;
1426         u32 __user *eventsp = argp;
1427         u32 events_missed;
1428         u64 features;
1429         int r, abi_version = VHOST_SCSI_ABI_VERSION;
1430         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1431
1432         switch (ioctl) {
1433         case VHOST_SCSI_SET_ENDPOINT:
1434                 if (copy_from_user(&backend, argp, sizeof backend))
1435                         return -EFAULT;
1436                 if (backend.reserved != 0)
1437                         return -EOPNOTSUPP;
1438
1439                 return vhost_scsi_set_endpoint(vs, &backend);
1440         case VHOST_SCSI_CLEAR_ENDPOINT:
1441                 if (copy_from_user(&backend, argp, sizeof backend))
1442                         return -EFAULT;
1443                 if (backend.reserved != 0)
1444                         return -EOPNOTSUPP;
1445
1446                 return vhost_scsi_clear_endpoint(vs, &backend);
1447         case VHOST_SCSI_GET_ABI_VERSION:
1448                 if (copy_to_user(argp, &abi_version, sizeof abi_version))
1449                         return -EFAULT;
1450                 return 0;
1451         case VHOST_SCSI_SET_EVENTS_MISSED:
1452                 if (get_user(events_missed, eventsp))
1453                         return -EFAULT;
1454                 mutex_lock(&vq->mutex);
1455                 vs->vs_events_missed = events_missed;
1456                 mutex_unlock(&vq->mutex);
1457                 return 0;
1458         case VHOST_SCSI_GET_EVENTS_MISSED:
1459                 mutex_lock(&vq->mutex);
1460                 events_missed = vs->vs_events_missed;
1461                 mutex_unlock(&vq->mutex);
1462                 if (put_user(events_missed, eventsp))
1463                         return -EFAULT;
1464                 return 0;
1465         case VHOST_GET_FEATURES:
1466                 features = VHOST_SCSI_FEATURES;
1467                 if (copy_to_user(featurep, &features, sizeof features))
1468                         return -EFAULT;
1469                 return 0;
1470         case VHOST_SET_FEATURES:
1471                 if (copy_from_user(&features, featurep, sizeof features))
1472                         return -EFAULT;
1473                 return vhost_scsi_set_features(vs, features);
1474         default:
1475                 mutex_lock(&vs->dev.mutex);
1476                 r = vhost_dev_ioctl(&vs->dev, ioctl, argp);
1477                 /* TODO: flush backend after dev ioctl. */
1478                 if (r == -ENOIOCTLCMD)
1479                         r = vhost_vring_ioctl(&vs->dev, ioctl, argp);
1480                 mutex_unlock(&vs->dev.mutex);
1481                 return r;
1482         }
1483 }
1484
1485 #ifdef CONFIG_COMPAT
1486 static long vhost_scsi_compat_ioctl(struct file *f, unsigned int ioctl,
1487                                 unsigned long arg)
1488 {
1489         return vhost_scsi_ioctl(f, ioctl, (unsigned long)compat_ptr(arg));
1490 }
1491 #endif
1492
1493 static const struct file_operations vhost_scsi_fops = {
1494         .owner          = THIS_MODULE,
1495         .release        = vhost_scsi_release,
1496         .unlocked_ioctl = vhost_scsi_ioctl,
1497 #ifdef CONFIG_COMPAT
1498         .compat_ioctl   = vhost_scsi_compat_ioctl,
1499 #endif
1500         .open           = vhost_scsi_open,
1501         .llseek         = noop_llseek,
1502 };
1503
1504 static struct miscdevice vhost_scsi_misc = {
1505         MISC_DYNAMIC_MINOR,
1506         "vhost-scsi",
1507         &vhost_scsi_fops,
1508 };
1509
1510 static int __init vhost_scsi_register(void)
1511 {
1512         return misc_register(&vhost_scsi_misc);
1513 }
1514
1515 static int vhost_scsi_deregister(void)
1516 {
1517         return misc_deregister(&vhost_scsi_misc);
1518 }
1519
1520 static char *tcm_vhost_dump_proto_id(struct tcm_vhost_tport *tport)
1521 {
1522         switch (tport->tport_proto_id) {
1523         case SCSI_PROTOCOL_SAS:
1524                 return "SAS";
1525         case SCSI_PROTOCOL_FCP:
1526                 return "FCP";
1527         case SCSI_PROTOCOL_ISCSI:
1528                 return "iSCSI";
1529         default:
1530                 break;
1531         }
1532
1533         return "Unknown";
1534 }
1535
1536 static void
1537 tcm_vhost_do_plug(struct tcm_vhost_tpg *tpg,
1538                   struct se_lun *lun, bool plug)
1539 {
1540
1541         struct vhost_scsi *vs = tpg->vhost_scsi;
1542         struct vhost_virtqueue *vq;
1543         u32 reason;
1544
1545         if (!vs)
1546                 return;
1547
1548         mutex_lock(&vs->dev.mutex);
1549         if (!vhost_has_feature(&vs->dev, VIRTIO_SCSI_F_HOTPLUG)) {
1550                 mutex_unlock(&vs->dev.mutex);
1551                 return;
1552         }
1553
1554         if (plug)
1555                 reason = VIRTIO_SCSI_EVT_RESET_RESCAN;
1556         else
1557                 reason = VIRTIO_SCSI_EVT_RESET_REMOVED;
1558
1559         vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1560         mutex_lock(&vq->mutex);
1561         tcm_vhost_send_evt(vs, tpg, lun,
1562                         VIRTIO_SCSI_T_TRANSPORT_RESET, reason);
1563         mutex_unlock(&vq->mutex);
1564         mutex_unlock(&vs->dev.mutex);
1565 }
1566
1567 static void tcm_vhost_hotplug(struct tcm_vhost_tpg *tpg, struct se_lun *lun)
1568 {
1569         tcm_vhost_do_plug(tpg, lun, true);
1570 }
1571
1572 static void tcm_vhost_hotunplug(struct tcm_vhost_tpg *tpg, struct se_lun *lun)
1573 {
1574         tcm_vhost_do_plug(tpg, lun, false);
1575 }
1576
1577 static int tcm_vhost_port_link(struct se_portal_group *se_tpg,
1578                                struct se_lun *lun)
1579 {
1580         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1581                                 struct tcm_vhost_tpg, se_tpg);
1582
1583         mutex_lock(&tcm_vhost_mutex);
1584
1585         mutex_lock(&tpg->tv_tpg_mutex);
1586         tpg->tv_tpg_port_count++;
1587         mutex_unlock(&tpg->tv_tpg_mutex);
1588
1589         tcm_vhost_hotplug(tpg, lun);
1590
1591         mutex_unlock(&tcm_vhost_mutex);
1592
1593         return 0;
1594 }
1595
1596 static void tcm_vhost_port_unlink(struct se_portal_group *se_tpg,
1597                                   struct se_lun *lun)
1598 {
1599         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1600                                 struct tcm_vhost_tpg, se_tpg);
1601
1602         mutex_lock(&tcm_vhost_mutex);
1603
1604         mutex_lock(&tpg->tv_tpg_mutex);
1605         tpg->tv_tpg_port_count--;
1606         mutex_unlock(&tpg->tv_tpg_mutex);
1607
1608         tcm_vhost_hotunplug(tpg, lun);
1609
1610         mutex_unlock(&tcm_vhost_mutex);
1611 }
1612
1613 static struct se_node_acl *
1614 tcm_vhost_make_nodeacl(struct se_portal_group *se_tpg,
1615                        struct config_group *group,
1616                        const char *name)
1617 {
1618         struct se_node_acl *se_nacl, *se_nacl_new;
1619         struct tcm_vhost_nacl *nacl;
1620         u64 wwpn = 0;
1621         u32 nexus_depth;
1622
1623         /* tcm_vhost_parse_wwn(name, &wwpn, 1) < 0)
1624                 return ERR_PTR(-EINVAL); */
1625         se_nacl_new = tcm_vhost_alloc_fabric_acl(se_tpg);
1626         if (!se_nacl_new)
1627                 return ERR_PTR(-ENOMEM);
1628
1629         nexus_depth = 1;
1630         /*
1631          * se_nacl_new may be released by core_tpg_add_initiator_node_acl()
1632          * when converting a NodeACL from demo mode -> explict
1633          */
1634         se_nacl = core_tpg_add_initiator_node_acl(se_tpg, se_nacl_new,
1635                                 name, nexus_depth);
1636         if (IS_ERR(se_nacl)) {
1637                 tcm_vhost_release_fabric_acl(se_tpg, se_nacl_new);
1638                 return se_nacl;
1639         }
1640         /*
1641          * Locate our struct tcm_vhost_nacl and set the FC Nport WWPN
1642          */
1643         nacl = container_of(se_nacl, struct tcm_vhost_nacl, se_node_acl);
1644         nacl->iport_wwpn = wwpn;
1645
1646         return se_nacl;
1647 }
1648
1649 static void tcm_vhost_drop_nodeacl(struct se_node_acl *se_acl)
1650 {
1651         struct tcm_vhost_nacl *nacl = container_of(se_acl,
1652                                 struct tcm_vhost_nacl, se_node_acl);
1653         core_tpg_del_initiator_node_acl(se_acl->se_tpg, se_acl, 1);
1654         kfree(nacl);
1655 }
1656
1657 static int tcm_vhost_make_nexus(struct tcm_vhost_tpg *tpg,
1658                                 const char *name)
1659 {
1660         struct se_portal_group *se_tpg;
1661         struct tcm_vhost_nexus *tv_nexus;
1662
1663         mutex_lock(&tpg->tv_tpg_mutex);
1664         if (tpg->tpg_nexus) {
1665                 mutex_unlock(&tpg->tv_tpg_mutex);
1666                 pr_debug("tpg->tpg_nexus already exists\n");
1667                 return -EEXIST;
1668         }
1669         se_tpg = &tpg->se_tpg;
1670
1671         tv_nexus = kzalloc(sizeof(struct tcm_vhost_nexus), GFP_KERNEL);
1672         if (!tv_nexus) {
1673                 mutex_unlock(&tpg->tv_tpg_mutex);
1674                 pr_err("Unable to allocate struct tcm_vhost_nexus\n");
1675                 return -ENOMEM;
1676         }
1677         /*
1678          *  Initialize the struct se_session pointer
1679          */
1680         tv_nexus->tvn_se_sess = transport_init_session();
1681         if (IS_ERR(tv_nexus->tvn_se_sess)) {
1682                 mutex_unlock(&tpg->tv_tpg_mutex);
1683                 kfree(tv_nexus);
1684                 return -ENOMEM;
1685         }
1686         /*
1687          * Since we are running in 'demo mode' this call with generate a
1688          * struct se_node_acl for the tcm_vhost struct se_portal_group with
1689          * the SCSI Initiator port name of the passed configfs group 'name'.
1690          */
1691         tv_nexus->tvn_se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
1692                                 se_tpg, (unsigned char *)name);
1693         if (!tv_nexus->tvn_se_sess->se_node_acl) {
1694                 mutex_unlock(&tpg->tv_tpg_mutex);
1695                 pr_debug("core_tpg_check_initiator_node_acl() failed"
1696                                 " for %s\n", name);
1697                 transport_free_session(tv_nexus->tvn_se_sess);
1698                 kfree(tv_nexus);
1699                 return -ENOMEM;
1700         }
1701         /*
1702          * Now register the TCM vhost virtual I_T Nexus as active with the
1703          * call to __transport_register_session()
1704          */
1705         __transport_register_session(se_tpg, tv_nexus->tvn_se_sess->se_node_acl,
1706                         tv_nexus->tvn_se_sess, tv_nexus);
1707         tpg->tpg_nexus = tv_nexus;
1708
1709         mutex_unlock(&tpg->tv_tpg_mutex);
1710         return 0;
1711 }
1712
1713 static int tcm_vhost_drop_nexus(struct tcm_vhost_tpg *tpg)
1714 {
1715         struct se_session *se_sess;
1716         struct tcm_vhost_nexus *tv_nexus;
1717
1718         mutex_lock(&tpg->tv_tpg_mutex);
1719         tv_nexus = tpg->tpg_nexus;
1720         if (!tv_nexus) {
1721                 mutex_unlock(&tpg->tv_tpg_mutex);
1722                 return -ENODEV;
1723         }
1724
1725         se_sess = tv_nexus->tvn_se_sess;
1726         if (!se_sess) {
1727                 mutex_unlock(&tpg->tv_tpg_mutex);
1728                 return -ENODEV;
1729         }
1730
1731         if (tpg->tv_tpg_port_count != 0) {
1732                 mutex_unlock(&tpg->tv_tpg_mutex);
1733                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
1734                         " active TPG port count: %d\n",
1735                         tpg->tv_tpg_port_count);
1736                 return -EBUSY;
1737         }
1738
1739         if (tpg->tv_tpg_vhost_count != 0) {
1740                 mutex_unlock(&tpg->tv_tpg_mutex);
1741                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
1742                         " active TPG vhost count: %d\n",
1743                         tpg->tv_tpg_vhost_count);
1744                 return -EBUSY;
1745         }
1746
1747         pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated"
1748                 " %s Initiator Port: %s\n", tcm_vhost_dump_proto_id(tpg->tport),
1749                 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1750         /*
1751          * Release the SCSI I_T Nexus to the emulated vhost Target Port
1752          */
1753         transport_deregister_session(tv_nexus->tvn_se_sess);
1754         tpg->tpg_nexus = NULL;
1755         mutex_unlock(&tpg->tv_tpg_mutex);
1756
1757         kfree(tv_nexus);
1758         return 0;
1759 }
1760
1761 static ssize_t tcm_vhost_tpg_show_nexus(struct se_portal_group *se_tpg,
1762                                         char *page)
1763 {
1764         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1765                                 struct tcm_vhost_tpg, se_tpg);
1766         struct tcm_vhost_nexus *tv_nexus;
1767         ssize_t ret;
1768
1769         mutex_lock(&tpg->tv_tpg_mutex);
1770         tv_nexus = tpg->tpg_nexus;
1771         if (!tv_nexus) {
1772                 mutex_unlock(&tpg->tv_tpg_mutex);
1773                 return -ENODEV;
1774         }
1775         ret = snprintf(page, PAGE_SIZE, "%s\n",
1776                         tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1777         mutex_unlock(&tpg->tv_tpg_mutex);
1778
1779         return ret;
1780 }
1781
1782 static ssize_t tcm_vhost_tpg_store_nexus(struct se_portal_group *se_tpg,
1783                                          const char *page,
1784                                          size_t count)
1785 {
1786         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1787                                 struct tcm_vhost_tpg, se_tpg);
1788         struct tcm_vhost_tport *tport_wwn = tpg->tport;
1789         unsigned char i_port[TCM_VHOST_NAMELEN], *ptr, *port_ptr;
1790         int ret;
1791         /*
1792          * Shutdown the active I_T nexus if 'NULL' is passed..
1793          */
1794         if (!strncmp(page, "NULL", 4)) {
1795                 ret = tcm_vhost_drop_nexus(tpg);
1796                 return (!ret) ? count : ret;
1797         }
1798         /*
1799          * Otherwise make sure the passed virtual Initiator port WWN matches
1800          * the fabric protocol_id set in tcm_vhost_make_tport(), and call
1801          * tcm_vhost_make_nexus().
1802          */
1803         if (strlen(page) >= TCM_VHOST_NAMELEN) {
1804                 pr_err("Emulated NAA Sas Address: %s, exceeds"
1805                                 " max: %d\n", page, TCM_VHOST_NAMELEN);
1806                 return -EINVAL;
1807         }
1808         snprintf(&i_port[0], TCM_VHOST_NAMELEN, "%s", page);
1809
1810         ptr = strstr(i_port, "naa.");
1811         if (ptr) {
1812                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
1813                         pr_err("Passed SAS Initiator Port %s does not"
1814                                 " match target port protoid: %s\n", i_port,
1815                                 tcm_vhost_dump_proto_id(tport_wwn));
1816                         return -EINVAL;
1817                 }
1818                 port_ptr = &i_port[0];
1819                 goto check_newline;
1820         }
1821         ptr = strstr(i_port, "fc.");
1822         if (ptr) {
1823                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
1824                         pr_err("Passed FCP Initiator Port %s does not"
1825                                 " match target port protoid: %s\n", i_port,
1826                                 tcm_vhost_dump_proto_id(tport_wwn));
1827                         return -EINVAL;
1828                 }
1829                 port_ptr = &i_port[3]; /* Skip over "fc." */
1830                 goto check_newline;
1831         }
1832         ptr = strstr(i_port, "iqn.");
1833         if (ptr) {
1834                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
1835                         pr_err("Passed iSCSI Initiator Port %s does not"
1836                                 " match target port protoid: %s\n", i_port,
1837                                 tcm_vhost_dump_proto_id(tport_wwn));
1838                         return -EINVAL;
1839                 }
1840                 port_ptr = &i_port[0];
1841                 goto check_newline;
1842         }
1843         pr_err("Unable to locate prefix for emulated Initiator Port:"
1844                         " %s\n", i_port);
1845         return -EINVAL;
1846         /*
1847          * Clear any trailing newline for the NAA WWN
1848          */
1849 check_newline:
1850         if (i_port[strlen(i_port)-1] == '\n')
1851                 i_port[strlen(i_port)-1] = '\0';
1852
1853         ret = tcm_vhost_make_nexus(tpg, port_ptr);
1854         if (ret < 0)
1855                 return ret;
1856
1857         return count;
1858 }
1859
1860 TF_TPG_BASE_ATTR(tcm_vhost, nexus, S_IRUGO | S_IWUSR);
1861
1862 static struct configfs_attribute *tcm_vhost_tpg_attrs[] = {
1863         &tcm_vhost_tpg_nexus.attr,
1864         NULL,
1865 };
1866
1867 static struct se_portal_group *
1868 tcm_vhost_make_tpg(struct se_wwn *wwn,
1869                    struct config_group *group,
1870                    const char *name)
1871 {
1872         struct tcm_vhost_tport *tport = container_of(wwn,
1873                         struct tcm_vhost_tport, tport_wwn);
1874
1875         struct tcm_vhost_tpg *tpg;
1876         unsigned long tpgt;
1877         int ret;
1878
1879         if (strstr(name, "tpgt_") != name)
1880                 return ERR_PTR(-EINVAL);
1881         if (kstrtoul(name + 5, 10, &tpgt) || tpgt > UINT_MAX)
1882                 return ERR_PTR(-EINVAL);
1883
1884         tpg = kzalloc(sizeof(struct tcm_vhost_tpg), GFP_KERNEL);
1885         if (!tpg) {
1886                 pr_err("Unable to allocate struct tcm_vhost_tpg");
1887                 return ERR_PTR(-ENOMEM);
1888         }
1889         mutex_init(&tpg->tv_tpg_mutex);
1890         INIT_LIST_HEAD(&tpg->tv_tpg_list);
1891         tpg->tport = tport;
1892         tpg->tport_tpgt = tpgt;
1893
1894         ret = core_tpg_register(&tcm_vhost_fabric_configfs->tf_ops, wwn,
1895                                 &tpg->se_tpg, tpg, TRANSPORT_TPG_TYPE_NORMAL);
1896         if (ret < 0) {
1897                 kfree(tpg);
1898                 return NULL;
1899         }
1900         mutex_lock(&tcm_vhost_mutex);
1901         list_add_tail(&tpg->tv_tpg_list, &tcm_vhost_list);
1902         mutex_unlock(&tcm_vhost_mutex);
1903
1904         return &tpg->se_tpg;
1905 }
1906
1907 static void tcm_vhost_drop_tpg(struct se_portal_group *se_tpg)
1908 {
1909         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1910                                 struct tcm_vhost_tpg, se_tpg);
1911
1912         mutex_lock(&tcm_vhost_mutex);
1913         list_del(&tpg->tv_tpg_list);
1914         mutex_unlock(&tcm_vhost_mutex);
1915         /*
1916          * Release the virtual I_T Nexus for this vhost TPG
1917          */
1918         tcm_vhost_drop_nexus(tpg);
1919         /*
1920          * Deregister the se_tpg from TCM..
1921          */
1922         core_tpg_deregister(se_tpg);
1923         kfree(tpg);
1924 }
1925
1926 static struct se_wwn *
1927 tcm_vhost_make_tport(struct target_fabric_configfs *tf,
1928                      struct config_group *group,
1929                      const char *name)
1930 {
1931         struct tcm_vhost_tport *tport;
1932         char *ptr;
1933         u64 wwpn = 0;
1934         int off = 0;
1935
1936         /* if (tcm_vhost_parse_wwn(name, &wwpn, 1) < 0)
1937                 return ERR_PTR(-EINVAL); */
1938
1939         tport = kzalloc(sizeof(struct tcm_vhost_tport), GFP_KERNEL);
1940         if (!tport) {
1941                 pr_err("Unable to allocate struct tcm_vhost_tport");
1942                 return ERR_PTR(-ENOMEM);
1943         }
1944         tport->tport_wwpn = wwpn;
1945         /*
1946          * Determine the emulated Protocol Identifier and Target Port Name
1947          * based on the incoming configfs directory name.
1948          */
1949         ptr = strstr(name, "naa.");
1950         if (ptr) {
1951                 tport->tport_proto_id = SCSI_PROTOCOL_SAS;
1952                 goto check_len;
1953         }
1954         ptr = strstr(name, "fc.");
1955         if (ptr) {
1956                 tport->tport_proto_id = SCSI_PROTOCOL_FCP;
1957                 off = 3; /* Skip over "fc." */
1958                 goto check_len;
1959         }
1960         ptr = strstr(name, "iqn.");
1961         if (ptr) {
1962                 tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
1963                 goto check_len;
1964         }
1965
1966         pr_err("Unable to locate prefix for emulated Target Port:"
1967                         " %s\n", name);
1968         kfree(tport);
1969         return ERR_PTR(-EINVAL);
1970
1971 check_len:
1972         if (strlen(name) >= TCM_VHOST_NAMELEN) {
1973                 pr_err("Emulated %s Address: %s, exceeds"
1974                         " max: %d\n", name, tcm_vhost_dump_proto_id(tport),
1975                         TCM_VHOST_NAMELEN);
1976                 kfree(tport);
1977                 return ERR_PTR(-EINVAL);
1978         }
1979         snprintf(&tport->tport_name[0], TCM_VHOST_NAMELEN, "%s", &name[off]);
1980
1981         pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target"
1982                 " %s Address: %s\n", tcm_vhost_dump_proto_id(tport), name);
1983
1984         return &tport->tport_wwn;
1985 }
1986
1987 static void tcm_vhost_drop_tport(struct se_wwn *wwn)
1988 {
1989         struct tcm_vhost_tport *tport = container_of(wwn,
1990                                 struct tcm_vhost_tport, tport_wwn);
1991
1992         pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target"
1993                 " %s Address: %s\n", tcm_vhost_dump_proto_id(tport),
1994                 tport->tport_name);
1995
1996         kfree(tport);
1997 }
1998
1999 static ssize_t
2000 tcm_vhost_wwn_show_attr_version(struct target_fabric_configfs *tf,
2001                                 char *page)
2002 {
2003         return sprintf(page, "TCM_VHOST fabric module %s on %s/%s"
2004                 "on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname,
2005                 utsname()->machine);
2006 }
2007
2008 TF_WWN_ATTR_RO(tcm_vhost, version);
2009
2010 static struct configfs_attribute *tcm_vhost_wwn_attrs[] = {
2011         &tcm_vhost_wwn_version.attr,
2012         NULL,
2013 };
2014
2015 static struct target_core_fabric_ops tcm_vhost_ops = {
2016         .get_fabric_name                = tcm_vhost_get_fabric_name,
2017         .get_fabric_proto_ident         = tcm_vhost_get_fabric_proto_ident,
2018         .tpg_get_wwn                    = tcm_vhost_get_fabric_wwn,
2019         .tpg_get_tag                    = tcm_vhost_get_tag,
2020         .tpg_get_default_depth          = tcm_vhost_get_default_depth,
2021         .tpg_get_pr_transport_id        = tcm_vhost_get_pr_transport_id,
2022         .tpg_get_pr_transport_id_len    = tcm_vhost_get_pr_transport_id_len,
2023         .tpg_parse_pr_out_transport_id  = tcm_vhost_parse_pr_out_transport_id,
2024         .tpg_check_demo_mode            = tcm_vhost_check_true,
2025         .tpg_check_demo_mode_cache      = tcm_vhost_check_true,
2026         .tpg_check_demo_mode_write_protect = tcm_vhost_check_false,
2027         .tpg_check_prod_mode_write_protect = tcm_vhost_check_false,
2028         .tpg_alloc_fabric_acl           = tcm_vhost_alloc_fabric_acl,
2029         .tpg_release_fabric_acl         = tcm_vhost_release_fabric_acl,
2030         .tpg_get_inst_index             = tcm_vhost_tpg_get_inst_index,
2031         .release_cmd                    = tcm_vhost_release_cmd,
2032         .shutdown_session               = tcm_vhost_shutdown_session,
2033         .close_session                  = tcm_vhost_close_session,
2034         .sess_get_index                 = tcm_vhost_sess_get_index,
2035         .sess_get_initiator_sid         = NULL,
2036         .write_pending                  = tcm_vhost_write_pending,
2037         .write_pending_status           = tcm_vhost_write_pending_status,
2038         .set_default_node_attributes    = tcm_vhost_set_default_node_attrs,
2039         .get_task_tag                   = tcm_vhost_get_task_tag,
2040         .get_cmd_state                  = tcm_vhost_get_cmd_state,
2041         .queue_data_in                  = tcm_vhost_queue_data_in,
2042         .queue_status                   = tcm_vhost_queue_status,
2043         .queue_tm_rsp                   = tcm_vhost_queue_tm_rsp,
2044         /*
2045          * Setup callers for generic logic in target_core_fabric_configfs.c
2046          */
2047         .fabric_make_wwn                = tcm_vhost_make_tport,
2048         .fabric_drop_wwn                = tcm_vhost_drop_tport,
2049         .fabric_make_tpg                = tcm_vhost_make_tpg,
2050         .fabric_drop_tpg                = tcm_vhost_drop_tpg,
2051         .fabric_post_link               = tcm_vhost_port_link,
2052         .fabric_pre_unlink              = tcm_vhost_port_unlink,
2053         .fabric_make_np                 = NULL,
2054         .fabric_drop_np                 = NULL,
2055         .fabric_make_nodeacl            = tcm_vhost_make_nodeacl,
2056         .fabric_drop_nodeacl            = tcm_vhost_drop_nodeacl,
2057 };
2058
2059 static int tcm_vhost_register_configfs(void)
2060 {
2061         struct target_fabric_configfs *fabric;
2062         int ret;
2063
2064         pr_debug("TCM_VHOST fabric module %s on %s/%s"
2065                 " on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname,
2066                 utsname()->machine);
2067         /*
2068          * Register the top level struct config_item_type with TCM core
2069          */
2070         fabric = target_fabric_configfs_init(THIS_MODULE, "vhost");
2071         if (IS_ERR(fabric)) {
2072                 pr_err("target_fabric_configfs_init() failed\n");
2073                 return PTR_ERR(fabric);
2074         }
2075         /*
2076          * Setup fabric->tf_ops from our local tcm_vhost_ops
2077          */
2078         fabric->tf_ops = tcm_vhost_ops;
2079         /*
2080          * Setup default attribute lists for various fabric->tf_cit_tmpl
2081          */
2082         TF_CIT_TMPL(fabric)->tfc_wwn_cit.ct_attrs = tcm_vhost_wwn_attrs;
2083         TF_CIT_TMPL(fabric)->tfc_tpg_base_cit.ct_attrs = tcm_vhost_tpg_attrs;
2084         TF_CIT_TMPL(fabric)->tfc_tpg_attrib_cit.ct_attrs = NULL;
2085         TF_CIT_TMPL(fabric)->tfc_tpg_param_cit.ct_attrs = NULL;
2086         TF_CIT_TMPL(fabric)->tfc_tpg_np_base_cit.ct_attrs = NULL;
2087         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_base_cit.ct_attrs = NULL;
2088         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_attrib_cit.ct_attrs = NULL;
2089         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_auth_cit.ct_attrs = NULL;
2090         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_param_cit.ct_attrs = NULL;
2091         /*
2092          * Register the fabric for use within TCM
2093          */
2094         ret = target_fabric_configfs_register(fabric);
2095         if (ret < 0) {
2096                 pr_err("target_fabric_configfs_register() failed"
2097                                 " for TCM_VHOST\n");
2098                 return ret;
2099         }
2100         /*
2101          * Setup our local pointer to *fabric
2102          */
2103         tcm_vhost_fabric_configfs = fabric;
2104         pr_debug("TCM_VHOST[0] - Set fabric -> tcm_vhost_fabric_configfs\n");
2105         return 0;
2106 };
2107
2108 static void tcm_vhost_deregister_configfs(void)
2109 {
2110         if (!tcm_vhost_fabric_configfs)
2111                 return;
2112
2113         target_fabric_configfs_deregister(tcm_vhost_fabric_configfs);
2114         tcm_vhost_fabric_configfs = NULL;
2115         pr_debug("TCM_VHOST[0] - Cleared tcm_vhost_fabric_configfs\n");
2116 };
2117
2118 static int __init tcm_vhost_init(void)
2119 {
2120         int ret = -ENOMEM;
2121         /*
2122          * Use our own dedicated workqueue for submitting I/O into
2123          * target core to avoid contention within system_wq.
2124          */
2125         tcm_vhost_workqueue = alloc_workqueue("tcm_vhost", 0, 0);
2126         if (!tcm_vhost_workqueue)
2127                 goto out;
2128
2129         ret = vhost_scsi_register();
2130         if (ret < 0)
2131                 goto out_destroy_workqueue;
2132
2133         ret = tcm_vhost_register_configfs();
2134         if (ret < 0)
2135                 goto out_vhost_scsi_deregister;
2136
2137         return 0;
2138
2139 out_vhost_scsi_deregister:
2140         vhost_scsi_deregister();
2141 out_destroy_workqueue:
2142         destroy_workqueue(tcm_vhost_workqueue);
2143 out:
2144         return ret;
2145 };
2146
2147 static void tcm_vhost_exit(void)
2148 {
2149         tcm_vhost_deregister_configfs();
2150         vhost_scsi_deregister();
2151         destroy_workqueue(tcm_vhost_workqueue);
2152 };
2153
2154 MODULE_DESCRIPTION("VHOST_SCSI series fabric driver");
2155 MODULE_ALIAS("tcm_vhost");
2156 MODULE_LICENSE("GPL");
2157 module_init(tcm_vhost_init);
2158 module_exit(tcm_vhost_exit);