drivers/vhost/scsi.c

   1 /*******************************************************************************
   2  * Vhost kernel TCM fabric driver for virtio SCSI initiators
   3  *
   4  * (C) Copyright 2010-2012 RisingTide Systems LLC.
   5  * (C) Copyright 2010-2012 IBM Corp.
   6  *
   7  * Licensed to the Linux Foundation under the General Public License (GPL) version 2.
   8  *
   9  * Authors: Nicholas A. Bellinger <nab@risingtidesystems.com>
  10  *          Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  ****************************************************************************/
  23
  24 #include <linux/module.h>
  25 #include <linux/moduleparam.h>
  26 #include <generated/utsrelease.h>
  27 #include <linux/utsname.h>
  28 #include <linux/init.h>
  29 #include <linux/slab.h>
  30 #include <linux/kthread.h>
  31 #include <linux/types.h>
  32 #include <linux/string.h>
  33 #include <linux/configfs.h>
  34 #include <linux/ctype.h>
  35 #include <linux/compat.h>
  36 #include <linux/eventfd.h>
  37 #include <linux/fs.h>
  38 #include <linux/miscdevice.h>
  39 #include <asm/unaligned.h>
  40 #include <scsi/scsi.h>
  41 #include <scsi/scsi_tcq.h>
  42 #include <target/target_core_base.h>
  43 #include <target/target_core_fabric.h>
  44 #include <target/target_core_fabric_configfs.h>
  45 #include <target/target_core_configfs.h>
  46 #include <target/configfs_macros.h>
  47 #include <linux/vhost.h>
  48 #include <linux/virtio_scsi.h>
  49 #include <linux/llist.h>
  50 #include <linux/bitmap.h>
  51
  52 #include "vhost.h"
  53
  54 #define TCM_VHOST_VERSION  "v0.1"
  55 #define TCM_VHOST_NAMELEN 256
  56 #define TCM_VHOST_MAX_CDB_SIZE 32
  57
  58 struct vhost_scsi_inflight {
  59         /* Wait for the flush operation to finish */
  60         struct completion comp;
  61         /* Refcount for the inflight reqs */
  62         struct kref kref;
  63 };
  64
  65 struct tcm_vhost_cmd {
  66         /* Descriptor from vhost_get_vq_desc() for virt_queue segment */
  67         int tvc_vq_desc;
  68         /* virtio-scsi initiator task attribute */
  69         int tvc_task_attr;
  70         /* virtio-scsi initiator data direction */
  71         enum dma_data_direction tvc_data_direction;
  72         /* Expected data transfer length from virtio-scsi header */
  73         u32 tvc_exp_data_len;
  74         /* The Tag from include/linux/virtio_scsi.h:struct virtio_scsi_cmd_req */
  75         u64 tvc_tag;
  76         /* The number of scatterlists associated with this cmd */
  77         u32 tvc_sgl_count;
  78         /* Saved unpacked SCSI LUN for tcm_vhost_submission_work() */
  79         u32 tvc_lun;
  80         /* Pointer to the SGL formatted memory from virtio-scsi */
  81         struct scatterlist *tvc_sgl;
  82         /* Pointer to response */
  83         struct virtio_scsi_cmd_resp __user *tvc_resp;
  84         /* Pointer to vhost_scsi for our device */
  85         struct vhost_scsi *tvc_vhost;
  86         /* Pointer to vhost_virtqueue for the cmd */
  87         struct vhost_virtqueue *tvc_vq;
  88         /* Pointer to vhost nexus memory */
  89         struct tcm_vhost_nexus *tvc_nexus;
  90         /* The TCM I/O descriptor that is accessed via container_of() */
  91         struct se_cmd tvc_se_cmd;
  92         /* work item used for cmwq dispatch to tcm_vhost_submission_work() */
  93         struct work_struct work;
  94         /* Copy of the incoming SCSI command descriptor block (CDB) */
  95         unsigned char tvc_cdb[TCM_VHOST_MAX_CDB_SIZE];
  96         /* Sense buffer that will be mapped into outgoing status */
  97         unsigned char tvc_sense_buf[TRANSPORT_SENSE_BUFFER];
  98         /* Completed commands list, serviced from vhost worker thread */
  99         struct llist_node tvc_completion_list;
 100         /* Used to track inflight cmd */
 101         struct vhost_scsi_inflight *inflight;
 102 };
 103
 104 struct tcm_vhost_nexus {
 105         /* Pointer to TCM session for I_T Nexus */
 106         struct se_session *tvn_se_sess;
 107 };
 108
 109 struct tcm_vhost_nacl {
 110         /* Binary World Wide unique Port Name for Vhost Initiator port */
 111         u64 iport_wwpn;
 112         /* ASCII formatted WWPN for Sas Initiator port */
 113         char iport_name[TCM_VHOST_NAMELEN];
 114         /* Returned by tcm_vhost_make_nodeacl() */
 115         struct se_node_acl se_node_acl;
 116 };
 117
 118 struct tcm_vhost_tpg {
 119         /* Vhost port target portal group tag for TCM */
 120         u16 tport_tpgt;
 121         /* Used to track number of TPG Port/Lun Links wrt to explict I_T Nexus shutdown */
 122         int tv_tpg_port_count;
 123         /* Used for vhost_scsi device reference to tpg_nexus, protected by tv_tpg_mutex */
 124         int tv_tpg_vhost_count;
 125         /* list for tcm_vhost_list */
 126         struct list_head tv_tpg_list;
 127         /* Used to protect access for tpg_nexus */
 128         struct mutex tv_tpg_mutex;
 129         /* Pointer to the TCM VHost I_T Nexus for this TPG endpoint */
 130         struct tcm_vhost_nexus *tpg_nexus;
 131         /* Pointer back to tcm_vhost_tport */
 132         struct tcm_vhost_tport *tport;
 133         /* Returned by tcm_vhost_make_tpg() */
 134         struct se_portal_group se_tpg;
 135         /* Pointer back to vhost_scsi, protected by tv_tpg_mutex */
 136         struct vhost_scsi *vhost_scsi;
 137 };
 138
 139 struct tcm_vhost_tport {
 140         /* SCSI protocol the tport is providing */
 141         u8 tport_proto_id;
 142         /* Binary World Wide unique Port Name for Vhost Target port */
 143         u64 tport_wwpn;
 144         /* ASCII formatted WWPN for Vhost Target port */
 145         char tport_name[TCM_VHOST_NAMELEN];
 146         /* Returned by tcm_vhost_make_tport() */
 147         struct se_wwn tport_wwn;
 148 };
 149
 150 struct tcm_vhost_evt {
 151         /* event to be sent to guest */
 152         struct virtio_scsi_event event;
 153         /* event list, serviced from vhost worker thread */
 154         struct llist_node list;
 155 };
 156
 157 enum {
 158         VHOST_SCSI_VQ_CTL = 0,
 159         VHOST_SCSI_VQ_EVT = 1,
 160         VHOST_SCSI_VQ_IO = 2,
 161 };
 162
 163 enum {
 164         VHOST_SCSI_FEATURES = VHOST_FEATURES | (1ULL << VIRTIO_SCSI_F_HOTPLUG)
 165 };
 166
 167 #define VHOST_SCSI_MAX_TARGET   256
 168 #define VHOST_SCSI_MAX_VQ       128
 169 #define VHOST_SCSI_MAX_EVENT    128
 170
 171 struct vhost_scsi_virtqueue {
 172         struct vhost_virtqueue vq;
 173         /*
 174          * Reference counting for inflight reqs, used for flush operation. At
 175          * each time, one reference tracks new commands submitted, while we
 176          * wait for another one to reach 0.
 177          */
 178         struct vhost_scsi_inflight inflights[2];
 179         /*
 180          * Indicate current inflight in use, protected by vq->mutex.
 181          * Writers must also take dev mutex and flush under it.
 182          */
 183         int inflight_idx;
 184 };
 185
 186 struct vhost_scsi {
 187         /* Protected by vhost_scsi->dev.mutex */
 188         struct tcm_vhost_tpg **vs_tpg;
 189         char vs_vhost_wwpn[TRANSPORT_IQN_LEN];
 190
 191         struct vhost_dev dev;
 192         struct vhost_scsi_virtqueue vqs[VHOST_SCSI_MAX_VQ];
 193
 194         struct vhost_work vs_completion_work; /* cmd completion work item */
 195         struct llist_head vs_completion_list; /* cmd completion queue */
 196
 197         struct vhost_work vs_event_work; /* evt injection work item */
 198         struct llist_head vs_event_list; /* evt injection queue */
 199
 200         bool vs_events_missed; /* any missed events, protected by vq->mutex */
 201         int vs_events_nr; /* num of pending events, protected by vq->mutex */
 202 };
 203
 204 /* Local pointer to allocated TCM configfs fabric module */
 205 static struct target_fabric_configfs *tcm_vhost_fabric_configfs;
 206
 207 static struct workqueue_struct *tcm_vhost_workqueue;
 208
 209 /* Global spinlock to protect tcm_vhost TPG list for vhost IOCTL access */
 210 static DEFINE_MUTEX(tcm_vhost_mutex);
 211 static LIST_HEAD(tcm_vhost_list);
 212
 213 static int iov_num_pages(struct iovec *iov)
 214 {
 215         return (PAGE_ALIGN((unsigned long)iov->iov_base + iov->iov_len) -
 216                ((unsigned long)iov->iov_base & PAGE_MASK)) >> PAGE_SHIFT;
 217 }
 218
 219 static void tcm_vhost_done_inflight(struct kref *kref)
 220 {
 221         struct vhost_scsi_inflight *inflight;
 222
 223         inflight = container_of(kref, struct vhost_scsi_inflight, kref);
 224         complete(&inflight->comp);
 225 }
 226
 227 static void tcm_vhost_init_inflight(struct vhost_scsi *vs,
 228                                     struct vhost_scsi_inflight *old_inflight[])
 229 {
 230         struct vhost_scsi_inflight *new_inflight;
 231         struct vhost_virtqueue *vq;
 232         int idx, i;
 233
 234         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
 235                 vq = &vs->vqs[i].vq;
 236
 237                 mutex_lock(&vq->mutex);
 238
 239                 /* store old infight */
 240                 idx = vs->vqs[i].inflight_idx;
 241                 if (old_inflight)
 242                         old_inflight[i] = &vs->vqs[i].inflights[idx];
 243
 244                 /* setup new infight */
 245                 vs->vqs[i].inflight_idx = idx ^ 1;
 246                 new_inflight = &vs->vqs[i].inflights[idx ^ 1];
 247                 kref_init(&new_inflight->kref);
 248                 init_completion(&new_inflight->comp);
 249
 250                 mutex_unlock(&vq->mutex);
 251         }
 252 }
 253
 254 static struct vhost_scsi_inflight *
 255 tcm_vhost_get_inflight(struct vhost_virtqueue *vq)
 256 {
 257         struct vhost_scsi_inflight *inflight;
 258         struct vhost_scsi_virtqueue *svq;
 259
 260         svq = container_of(vq, struct vhost_scsi_virtqueue, vq);
 261         inflight = &svq->inflights[svq->inflight_idx];
 262         kref_get(&inflight->kref);
 263
 264         return inflight;
 265 }
 266
 267 static void tcm_vhost_put_inflight(struct vhost_scsi_inflight *inflight)
 268 {
 269         kref_put(&inflight->kref, tcm_vhost_done_inflight);
 270 }
 271
 272 static int tcm_vhost_check_true(struct se_portal_group *se_tpg)
 273 {
 274         return 1;
 275 }
 276
 277 static int tcm_vhost_check_false(struct se_portal_group *se_tpg)
 278 {
 279         return 0;
 280 }
 281
 282 static char *tcm_vhost_get_fabric_name(void)
 283 {
 284         return "vhost";
 285 }
 286
 287 static u8 tcm_vhost_get_fabric_proto_ident(struct se_portal_group *se_tpg)
 288 {
 289         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 290                                 struct tcm_vhost_tpg, se_tpg);
 291         struct tcm_vhost_tport *tport = tpg->tport;
 292
 293         switch (tport->tport_proto_id) {
 294         case SCSI_PROTOCOL_SAS:
 295                 return sas_get_fabric_proto_ident(se_tpg);
 296         case SCSI_PROTOCOL_FCP:
 297                 return fc_get_fabric_proto_ident(se_tpg);
 298         case SCSI_PROTOCOL_ISCSI:
 299                 return iscsi_get_fabric_proto_ident(se_tpg);
 300         default:
 301                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 302                         " SAS emulation\n", tport->tport_proto_id);
 303                 break;
 304         }
 305
 306         return sas_get_fabric_proto_ident(se_tpg);
 307 }
 308
 309 static char *tcm_vhost_get_fabric_wwn(struct se_portal_group *se_tpg)
 310 {
 311         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 312                                 struct tcm_vhost_tpg, se_tpg);
 313         struct tcm_vhost_tport *tport = tpg->tport;
 314
 315         return &tport->tport_name[0];
 316 }
 317
 318 static u16 tcm_vhost_get_tag(struct se_portal_group *se_tpg)
 319 {
 320         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 321                                 struct tcm_vhost_tpg, se_tpg);
 322         return tpg->tport_tpgt;
 323 }
 324
 325 static u32 tcm_vhost_get_default_depth(struct se_portal_group *se_tpg)
 326 {
 327         return 1;
 328 }
 329
 330 static u32
 331 tcm_vhost_get_pr_transport_id(struct se_portal_group *se_tpg,
 332                               struct se_node_acl *se_nacl,
 333                               struct t10_pr_registration *pr_reg,
 334                               int *format_code,
 335                               unsigned char *buf)
 336 {
 337         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 338                                 struct tcm_vhost_tpg, se_tpg);
 339         struct tcm_vhost_tport *tport = tpg->tport;
 340
 341         switch (tport->tport_proto_id) {
 342         case SCSI_PROTOCOL_SAS:
 343                 return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 344                                         format_code, buf);
 345         case SCSI_PROTOCOL_FCP:
 346                 return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 347                                         format_code, buf);
 348         case SCSI_PROTOCOL_ISCSI:
 349                 return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 350                                         format_code, buf);
 351         default:
 352                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 353                         " SAS emulation\n", tport->tport_proto_id);
 354                 break;
 355         }
 356
 357         return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 358                         format_code, buf);
 359 }
 360
 361 static u32
 362 tcm_vhost_get_pr_transport_id_len(struct se_portal_group *se_tpg,
 363                                   struct se_node_acl *se_nacl,
 364                                   struct t10_pr_registration *pr_reg,
 365                                   int *format_code)
 366 {
 367         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 368                                 struct tcm_vhost_tpg, se_tpg);
 369         struct tcm_vhost_tport *tport = tpg->tport;
 370
 371         switch (tport->tport_proto_id) {
 372         case SCSI_PROTOCOL_SAS:
 373                 return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 374                                         format_code);
 375         case SCSI_PROTOCOL_FCP:
 376                 return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 377                                         format_code);
 378         case SCSI_PROTOCOL_ISCSI:
 379                 return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 380                                         format_code);
 381         default:
 382                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 383                         " SAS emulation\n", tport->tport_proto_id);
 384                 break;
 385         }
 386
 387         return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 388                         format_code);
 389 }
 390
 391 static char *
 392 tcm_vhost_parse_pr_out_transport_id(struct se_portal_group *se_tpg,
 393                                     const char *buf,
 394                                     u32 *out_tid_len,
 395                                     char **port_nexus_ptr)
 396 {
 397         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 398                                 struct tcm_vhost_tpg, se_tpg);
 399         struct tcm_vhost_tport *tport = tpg->tport;
 400
 401         switch (tport->tport_proto_id) {
 402         case SCSI_PROTOCOL_SAS:
 403                 return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 404                                         port_nexus_ptr);
 405         case SCSI_PROTOCOL_FCP:
 406                 return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 407                                         port_nexus_ptr);
 408         case SCSI_PROTOCOL_ISCSI:
 409                 return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 410                                         port_nexus_ptr);
 411         default:
 412                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 413                         " SAS emulation\n", tport->tport_proto_id);
 414                 break;
 415         }
 416
 417         return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 418                         port_nexus_ptr);
 419 }
 420
 421 static struct se_node_acl *
 422 tcm_vhost_alloc_fabric_acl(struct se_portal_group *se_tpg)
 423 {
 424         struct tcm_vhost_nacl *nacl;
 425
 426         nacl = kzalloc(sizeof(struct tcm_vhost_nacl), GFP_KERNEL);
 427         if (!nacl) {
 428                 pr_err("Unable to allocate struct tcm_vhost_nacl\n");
 429                 return NULL;
 430         }
 431
 432         return &nacl->se_node_acl;
 433 }
 434
 435 static void
 436 tcm_vhost_release_fabric_acl(struct se_portal_group *se_tpg,
 437                              struct se_node_acl *se_nacl)
 438 {
 439         struct tcm_vhost_nacl *nacl = container_of(se_nacl,
 440                         struct tcm_vhost_nacl, se_node_acl);
 441         kfree(nacl);
 442 }
 443
 444 static u32 tcm_vhost_tpg_get_inst_index(struct se_portal_group *se_tpg)
 445 {
 446         return 1;
 447 }
 448
 449 static void tcm_vhost_release_cmd(struct se_cmd *se_cmd)
 450 {
 451         struct tcm_vhost_cmd *tv_cmd = container_of(se_cmd,
 452                                 struct tcm_vhost_cmd, tvc_se_cmd);
 453
 454         if (tv_cmd->tvc_sgl_count) {
 455                 u32 i;
 456                 for (i = 0; i < tv_cmd->tvc_sgl_count; i++)
 457                         put_page(sg_page(&tv_cmd->tvc_sgl[i]));
 458
 459                 kfree(tv_cmd->tvc_sgl);
 460         }
 461
 462         tcm_vhost_put_inflight(tv_cmd->inflight);
 463         kfree(tv_cmd);
 464 }
 465
 466 static int tcm_vhost_shutdown_session(struct se_session *se_sess)
 467 {
 468         return 0;
 469 }
 470
 471 static void tcm_vhost_close_session(struct se_session *se_sess)
 472 {
 473         return;
 474 }
 475
 476 static u32 tcm_vhost_sess_get_index(struct se_session *se_sess)
 477 {
 478         return 0;
 479 }
 480
 481 static int tcm_vhost_write_pending(struct se_cmd *se_cmd)
 482 {
 483         /* Go ahead and process the write immediately */
 484         target_execute_cmd(se_cmd);
 485         return 0;
 486 }
 487
 488 static int tcm_vhost_write_pending_status(struct se_cmd *se_cmd)
 489 {
 490         return 0;
 491 }
 492
 493 static void tcm_vhost_set_default_node_attrs(struct se_node_acl *nacl)
 494 {
 495         return;
 496 }
 497
 498 static u32 tcm_vhost_get_task_tag(struct se_cmd *se_cmd)
 499 {
 500         return 0;
 501 }
 502
 503 static int tcm_vhost_get_cmd_state(struct se_cmd *se_cmd)
 504 {
 505         return 0;
 506 }
 507
 508 static void vhost_scsi_complete_cmd(struct tcm_vhost_cmd *cmd)
 509 {
 510         struct vhost_scsi *vs = cmd->tvc_vhost;
 511
 512         llist_add(&cmd->tvc_completion_list, &vs->vs_completion_list);
 513
 514         vhost_work_queue(&vs->dev, &vs->vs_completion_work);
 515 }
 516
 517 static int tcm_vhost_queue_data_in(struct se_cmd *se_cmd)
 518 {
 519         struct tcm_vhost_cmd *cmd = container_of(se_cmd,
 520                                 struct tcm_vhost_cmd, tvc_se_cmd);
 521         vhost_scsi_complete_cmd(cmd);
 522         return 0;
 523 }
 524
 525 static int tcm_vhost_queue_status(struct se_cmd *se_cmd)
 526 {
 527         struct tcm_vhost_cmd *cmd = container_of(se_cmd,
 528                                 struct tcm_vhost_cmd, tvc_se_cmd);
 529         vhost_scsi_complete_cmd(cmd);
 530         return 0;
 531 }
 532
 533 static void tcm_vhost_queue_tm_rsp(struct se_cmd *se_cmd)
 534 {
 535         return;
 536 }
 537
 538 static void tcm_vhost_free_evt(struct vhost_scsi *vs, struct tcm_vhost_evt *evt)
 539 {
 540         vs->vs_events_nr--;
 541         kfree(evt);
 542 }
 543
 544 static struct tcm_vhost_evt *
 545 tcm_vhost_allocate_evt(struct vhost_scsi *vs,
 546                        u32 event, u32 reason)
 547 {
 548         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 549         struct tcm_vhost_evt *evt;
 550
 551         if (vs->vs_events_nr > VHOST_SCSI_MAX_EVENT) {
 552                 vs->vs_events_missed = true;
 553                 return NULL;
 554         }
 555
 556         evt = kzalloc(sizeof(*evt), GFP_KERNEL);
 557         if (!evt) {
 558                 vq_err(vq, "Failed to allocate tcm_vhost_evt\n");
 559                 vs->vs_events_missed = true;
 560                 return NULL;
 561         }
 562
 563         evt->event.event = event;
 564         evt->event.reason = reason;
 565         vs->vs_events_nr++;
 566
 567         return evt;
 568 }
 569
 570 static void vhost_scsi_free_cmd(struct tcm_vhost_cmd *cmd)
 571 {
 572         struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
 573
 574         /* TODO locking against target/backend threads? */
 575         transport_generic_free_cmd(se_cmd, 0);
 576
 577 }
 578
 579 static int vhost_scsi_check_stop_free(struct se_cmd *se_cmd)
 580 {
 581         return target_put_sess_cmd(se_cmd->se_sess, se_cmd);
 582 }
 583
 584 static void
 585 tcm_vhost_do_evt_work(struct vhost_scsi *vs, struct tcm_vhost_evt *evt)
 586 {
 587         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 588         struct virtio_scsi_event *event = &evt->event;
 589         struct virtio_scsi_event __user *eventp;
 590         unsigned out, in;
 591         int head, ret;
 592
 593         if (!vq->private_data) {
 594                 vs->vs_events_missed = true;
 595                 return;
 596         }
 597
 598 again:
 599         vhost_disable_notify(&vs->dev, vq);
 600         head = vhost_get_vq_desc(&vs->dev, vq, vq->iov,
 601                         ARRAY_SIZE(vq->iov), &out, &in,
 602                         NULL, NULL);
 603         if (head < 0) {
 604                 vs->vs_events_missed = true;
 605                 return;
 606         }
 607         if (head == vq->num) {
 608                 if (vhost_enable_notify(&vs->dev, vq))
 609                         goto again;
 610                 vs->vs_events_missed = true;
 611                 return;
 612         }
 613
 614         if ((vq->iov[out].iov_len != sizeof(struct virtio_scsi_event))) {
 615                 vq_err(vq, "Expecting virtio_scsi_event, got %zu bytes\n",
 616                                 vq->iov[out].iov_len);
 617                 vs->vs_events_missed = true;
 618                 return;
 619         }
 620
 621         if (vs->vs_events_missed) {
 622                 event->event |= VIRTIO_SCSI_T_EVENTS_MISSED;
 623                 vs->vs_events_missed = false;
 624         }
 625
 626         eventp = vq->iov[out].iov_base;
 627         ret = __copy_to_user(eventp, event, sizeof(*event));
 628         if (!ret)
 629                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 630         else
 631                 vq_err(vq, "Faulted on tcm_vhost_send_event\n");
 632 }
 633
 634 static void tcm_vhost_evt_work(struct vhost_work *work)
 635 {
 636         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 637                                         vs_event_work);
 638         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 639         struct tcm_vhost_evt *evt;
 640         struct llist_node *llnode;
 641
 642         mutex_lock(&vq->mutex);
 643         llnode = llist_del_all(&vs->vs_event_list);
 644         while (llnode) {
 645                 evt = llist_entry(llnode, struct tcm_vhost_evt, list);
 646                 llnode = llist_next(llnode);
 647                 tcm_vhost_do_evt_work(vs, evt);
 648                 tcm_vhost_free_evt(vs, evt);
 649         }
 650         mutex_unlock(&vq->mutex);
 651 }
 652
 653 /* Fill in status and signal that we are done processing this command
 654  *
 655  * This is scheduled in the vhost work queue so we are called with the owner
 656  * process mm and can access the vring.
 657  */
 658 static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
 659 {
 660         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 661                                         vs_completion_work);
 662         DECLARE_BITMAP(signal, VHOST_SCSI_MAX_VQ);
 663         struct virtio_scsi_cmd_resp v_rsp;
 664         struct tcm_vhost_cmd *cmd;
 665         struct llist_node *llnode;
 666         struct se_cmd *se_cmd;
 667         int ret, vq;
 668
 669         bitmap_zero(signal, VHOST_SCSI_MAX_VQ);
 670         llnode = llist_del_all(&vs->vs_completion_list);
 671         while (llnode) {
 672                 cmd = llist_entry(llnode, struct tcm_vhost_cmd,
 673                                      tvc_completion_list);
 674                 llnode = llist_next(llnode);
 675                 se_cmd = &cmd->tvc_se_cmd;
 676
 677                 pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__,
 678                         cmd, se_cmd->residual_count, se_cmd->scsi_status);
 679
 680                 memset(&v_rsp, 0, sizeof(v_rsp));
 681                 v_rsp.resid = se_cmd->residual_count;
 682                 /* TODO is status_qualifier field needed? */
 683                 v_rsp.status = se_cmd->scsi_status;
 684                 v_rsp.sense_len = se_cmd->scsi_sense_length;
 685                 memcpy(v_rsp.sense, cmd->tvc_sense_buf,
 686                        v_rsp.sense_len);
 687                 ret = copy_to_user(cmd->tvc_resp, &v_rsp, sizeof(v_rsp));
 688                 if (likely(ret == 0)) {
 689                         struct vhost_scsi_virtqueue *q;
 690                         vhost_add_used(cmd->tvc_vq, cmd->tvc_vq_desc, 0);
 691                         q = container_of(cmd->tvc_vq, struct vhost_scsi_virtqueue, vq);
 692                         vq = q - vs->vqs;
 693                         __set_bit(vq, signal);
 694                 } else
 695                         pr_err("Faulted on virtio_scsi_cmd_resp\n");
 696
 697                 vhost_scsi_free_cmd(cmd);
 698         }
 699
 700         vq = -1;
 701         while ((vq = find_next_bit(signal, VHOST_SCSI_MAX_VQ, vq + 1))
 702                 < VHOST_SCSI_MAX_VQ)
 703                 vhost_signal(&vs->dev, &vs->vqs[vq].vq);
 704 }
 705
 706 static struct tcm_vhost_cmd *
 707 vhost_scsi_allocate_cmd(struct vhost_virtqueue *vq,
 708                         struct tcm_vhost_tpg *tpg,
 709                         struct virtio_scsi_cmd_req *v_req,
 710                         u32 exp_data_len,
 711                         int data_direction)
 712 {
 713         struct tcm_vhost_cmd *cmd;
 714         struct tcm_vhost_nexus *tv_nexus;
 715
 716         tv_nexus = tpg->tpg_nexus;
 717         if (!tv_nexus) {
 718                 pr_err("Unable to locate active struct tcm_vhost_nexus\n");
 719                 return ERR_PTR(-EIO);
 720         }
 721
 722         cmd = kzalloc(sizeof(struct tcm_vhost_cmd), GFP_ATOMIC);
 723         if (!cmd) {
 724                 pr_err("Unable to allocate struct tcm_vhost_cmd\n");
 725                 return ERR_PTR(-ENOMEM);
 726         }
 727         cmd->tvc_tag = v_req->tag;
 728         cmd->tvc_task_attr = v_req->task_attr;
 729         cmd->tvc_exp_data_len = exp_data_len;
 730         cmd->tvc_data_direction = data_direction;
 731         cmd->tvc_nexus = tv_nexus;
 732         cmd->inflight = tcm_vhost_get_inflight(vq);
 733
 734         return cmd;
 735 }
 736
 737 /*
 738  * Map a user memory range into a scatterlist
 739  *
 740  * Returns the number of scatterlist entries used or -errno on error.
 741  */
 742 static int
 743 vhost_scsi_map_to_sgl(struct scatterlist *sgl,
 744                       unsigned int sgl_count,
 745                       struct iovec *iov,
 746                       int write)
 747 {
 748         unsigned int npages = 0, pages_nr, offset, nbytes;
 749         struct scatterlist *sg = sgl;
 750         void __user *ptr = iov->iov_base;
 751         size_t len = iov->iov_len;
 752         struct page **pages;
 753         int ret, i;
 754
 755         pages_nr = iov_num_pages(iov);
 756         if (pages_nr > sgl_count)
 757                 return -ENOBUFS;
 758
 759         pages = kmalloc(pages_nr * sizeof(struct page *), GFP_KERNEL);
 760         if (!pages)
 761                 return -ENOMEM;
 762
 763         ret = get_user_pages_fast((unsigned long)ptr, pages_nr, write, pages);
 764         /* No pages were pinned */
 765         if (ret < 0)
 766                 goto out;
 767         /* Less pages pinned than wanted */
 768         if (ret != pages_nr) {
 769                 for (i = 0; i < ret; i++)
 770                         put_page(pages[i]);
 771                 ret = -EFAULT;
 772                 goto out;
 773         }
 774
 775         while (len > 0) {
 776                 offset = (uintptr_t)ptr & ~PAGE_MASK;
 777                 nbytes = min_t(unsigned int, PAGE_SIZE - offset, len);
 778                 sg_set_page(sg, pages[npages], nbytes, offset);
 779                 ptr += nbytes;
 780                 len -= nbytes;
 781                 sg++;
 782                 npages++;
 783         }
 784
 785 out:
 786         kfree(pages);
 787         return ret;
 788 }
 789
 790 static int
 791 vhost_scsi_map_iov_to_sgl(struct tcm_vhost_cmd *cmd,
 792                           struct iovec *iov,
 793                           unsigned int niov,
 794                           int write)
 795 {
 796         int ret;
 797         unsigned int i;
 798         u32 sgl_count;
 799         struct scatterlist *sg;
 800
 801         /*
 802          * Find out how long sglist needs to be
 803          */
 804         sgl_count = 0;
 805         for (i = 0; i < niov; i++)
 806                 sgl_count += iov_num_pages(&iov[i]);
 807
 808         /* TODO overflow checking */
 809
 810         sg = kmalloc(sizeof(cmd->tvc_sgl[0]) * sgl_count, GFP_ATOMIC);
 811         if (!sg)
 812                 return -ENOMEM;
 813         pr_debug("%s sg %p sgl_count %u is_err %d\n", __func__,
 814                sg, sgl_count, !sg);
 815         sg_init_table(sg, sgl_count);
 816
 817         cmd->tvc_sgl = sg;
 818         cmd->tvc_sgl_count = sgl_count;
 819
 820         pr_debug("Mapping %u iovecs for %u pages\n", niov, sgl_count);
 821         for (i = 0; i < niov; i++) {
 822                 ret = vhost_scsi_map_to_sgl(sg, sgl_count, &iov[i], write);
 823                 if (ret < 0) {
 824                         for (i = 0; i < cmd->tvc_sgl_count; i++)
 825                                 put_page(sg_page(&cmd->tvc_sgl[i]));
 826                         kfree(cmd->tvc_sgl);
 827                         cmd->tvc_sgl = NULL;
 828                         cmd->tvc_sgl_count = 0;
 829                         return ret;
 830                 }
 831
 832                 sg += ret;
 833                 sgl_count -= ret;
 834         }
 835         return 0;
 836 }
 837
 838 static void tcm_vhost_submission_work(struct work_struct *work)
 839 {
 840         struct tcm_vhost_cmd *cmd =
 841                 container_of(work, struct tcm_vhost_cmd, work);
 842         struct tcm_vhost_nexus *tv_nexus;
 843         struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
 844         struct scatterlist *sg_ptr, *sg_bidi_ptr = NULL;
 845         int rc, sg_no_bidi = 0;
 846
 847         if (cmd->tvc_sgl_count) {
 848                 sg_ptr = cmd->tvc_sgl;
 849 /* FIXME: Fix BIDI operation in tcm_vhost_submission_work() */
 850 #if 0
 851                 if (se_cmd->se_cmd_flags & SCF_BIDI) {
 852                         sg_bidi_ptr = NULL;
 853                         sg_no_bidi = 0;
 854                 }
 855 #endif
 856         } else {
 857                 sg_ptr = NULL;
 858         }
 859         tv_nexus = cmd->tvc_nexus;
 860
 861         rc = target_submit_cmd_map_sgls(se_cmd, tv_nexus->tvn_se_sess,
 862                         cmd->tvc_cdb, &cmd->tvc_sense_buf[0],
 863                         cmd->tvc_lun, cmd->tvc_exp_data_len,
 864                         cmd->tvc_task_attr, cmd->tvc_data_direction,
 865                         TARGET_SCF_ACK_KREF, sg_ptr, cmd->tvc_sgl_count,
 866                         sg_bidi_ptr, sg_no_bidi);
 867         if (rc < 0) {
 868                 transport_send_check_condition_and_sense(se_cmd,
 869                                 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
 870                 transport_generic_free_cmd(se_cmd, 0);
 871         }
 872 }
 873
 874 static void
 875 vhost_scsi_send_bad_target(struct vhost_scsi *vs,
 876                            struct vhost_virtqueue *vq,
 877                            int head, unsigned out)
 878 {
 879         struct virtio_scsi_cmd_resp __user *resp;
 880         struct virtio_scsi_cmd_resp rsp;
 881         int ret;
 882
 883         memset(&rsp, 0, sizeof(rsp));
 884         rsp.response = VIRTIO_SCSI_S_BAD_TARGET;
 885         resp = vq->iov[out].iov_base;
 886         ret = __copy_to_user(resp, &rsp, sizeof(rsp));
 887         if (!ret)
 888                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 889         else
 890                 pr_err("Faulted on virtio_scsi_cmd_resp\n");
 891 }
 892
 893 static void
 894 vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
 895 {
 896         struct tcm_vhost_tpg **vs_tpg;
 897         struct virtio_scsi_cmd_req v_req;
 898         struct tcm_vhost_tpg *tpg;
 899         struct tcm_vhost_cmd *cmd;
 900         u32 exp_data_len, data_first, data_num, data_direction;
 901         unsigned out, in, i;
 902         int head, ret;
 903         u8 target;
 904
 905         /*
 906          * We can handle the vq only after the endpoint is setup by calling the
 907          * VHOST_SCSI_SET_ENDPOINT ioctl.
 908          *
 909          * TODO: Check that we are running from vhost_worker which acts
 910          * as read-side critical section for vhost kind of RCU.
 911          * See the comments in struct vhost_virtqueue in drivers/vhost/vhost.h
 912          */
 913         vs_tpg = rcu_dereference_check(vq->private_data, 1);
 914         if (!vs_tpg)
 915                 return;
 916
 917         mutex_lock(&vq->mutex);
 918         vhost_disable_notify(&vs->dev, vq);
 919
 920         for (;;) {
 921                 head = vhost_get_vq_desc(&vs->dev, vq, vq->iov,
 922                                         ARRAY_SIZE(vq->iov), &out, &in,
 923                                         NULL, NULL);
 924                 pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n",
 925                                         head, out, in);
 926                 /* On error, stop handling until the next kick. */
 927                 if (unlikely(head < 0))
 928                         break;
 929                 /* Nothing new?  Wait for eventfd to tell us they refilled. */
 930                 if (head == vq->num) {
 931                         if (unlikely(vhost_enable_notify(&vs->dev, vq))) {
 932                                 vhost_disable_notify(&vs->dev, vq);
 933                                 continue;
 934                         }
 935                         break;
 936                 }
 937
 938 /* FIXME: BIDI operation */
 939                 if (out == 1 && in == 1) {
 940                         data_direction = DMA_NONE;
 941                         data_first = 0;
 942                         data_num = 0;
 943                 } else if (out == 1 && in > 1) {
 944                         data_direction = DMA_FROM_DEVICE;
 945                         data_first = out + 1;
 946                         data_num = in - 1;
 947                 } else if (out > 1 && in == 1) {
 948                         data_direction = DMA_TO_DEVICE;
 949                         data_first = 1;
 950                         data_num = out - 1;
 951                 } else {
 952                         vq_err(vq, "Invalid buffer layout out: %u in: %u\n",
 953                                         out, in);
 954                         break;
 955                 }
 956
 957                 /*
 958                  * Check for a sane resp buffer so we can report errors to
 959                  * the guest.
 960                  */
 961                 if (unlikely(vq->iov[out].iov_len !=
 962                                         sizeof(struct virtio_scsi_cmd_resp))) {
 963                         vq_err(vq, "Expecting virtio_scsi_cmd_resp, got %zu"
 964                                 " bytes\n", vq->iov[out].iov_len);
 965                         break;
 966                 }
 967
 968                 if (unlikely(vq->iov[0].iov_len != sizeof(v_req))) {
 969                         vq_err(vq, "Expecting virtio_scsi_cmd_req, got %zu"
 970                                 " bytes\n", vq->iov[0].iov_len);
 971                         break;
 972                 }
 973                 pr_debug("Calling __copy_from_user: vq->iov[0].iov_base: %p,"
 974                         " len: %zu\n", vq->iov[0].iov_base, sizeof(v_req));
 975                 ret = __copy_from_user(&v_req, vq->iov[0].iov_base,
 976                                 sizeof(v_req));
 977                 if (unlikely(ret)) {
 978                         vq_err(vq, "Faulted on virtio_scsi_cmd_req\n");
 979                         break;
 980                 }
 981
 982                 /* Extract the tpgt */
 983                 target = v_req.lun[1];
 984                 tpg = ACCESS_ONCE(vs_tpg[target]);
 985
 986                 /* Target does not exist, fail the request */
 987                 if (unlikely(!tpg)) {
 988                         vhost_scsi_send_bad_target(vs, vq, head, out);
 989                         continue;
 990                 }
 991
 992                 exp_data_len = 0;
 993                 for (i = 0; i < data_num; i++)
 994                         exp_data_len += vq->iov[data_first + i].iov_len;
 995
 996                 cmd = vhost_scsi_allocate_cmd(vq, tpg, &v_req,
 997                                         exp_data_len, data_direction);
 998                 if (IS_ERR(cmd)) {
 999                         vq_err(vq, "vhost_scsi_allocate_cmd failed %ld\n",
1000                                         PTR_ERR(cmd));
1001                         goto err_cmd;
1002                 }
1003                 pr_debug("Allocated tv_cmd: %p exp_data_len: %d, data_direction"
1004                         ": %d\n", cmd, exp_data_len, data_direction);
1005
1006                 cmd->tvc_vhost = vs;
1007                 cmd->tvc_vq = vq;
1008                 cmd->tvc_resp = vq->iov[out].iov_base;
1009
1010                 /*
1011                  * Copy in the recieved CDB descriptor into cmd->tvc_cdb
1012                  * that will be used by tcm_vhost_new_cmd_map() and down into
1013                  * target_setup_cmd_from_cdb()
1014                  */
1015                 memcpy(cmd->tvc_cdb, v_req.cdb, TCM_VHOST_MAX_CDB_SIZE);
1016                 /*
1017                  * Check that the recieved CDB size does not exceeded our
1018                  * hardcoded max for tcm_vhost
1019                  */
1020                 /* TODO what if cdb was too small for varlen cdb header? */
1021                 if (unlikely(scsi_command_size(cmd->tvc_cdb) >
1022                                         TCM_VHOST_MAX_CDB_SIZE)) {
1023                         vq_err(vq, "Received SCSI CDB with command_size: %d that"
1024                                 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1025                                 scsi_command_size(cmd->tvc_cdb),
1026                                 TCM_VHOST_MAX_CDB_SIZE);
1027                         goto err_free;
1028                 }
1029                 cmd->tvc_lun = ((v_req.lun[2] << 8) | v_req.lun[3]) & 0x3FFF;
1030
1031                 pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n",
1032                         cmd->tvc_cdb[0], cmd->tvc_lun);
1033
1034                 if (data_direction != DMA_NONE) {
1035                         ret = vhost_scsi_map_iov_to_sgl(cmd,
1036                                         &vq->iov[data_first], data_num,
1037                                         data_direction == DMA_TO_DEVICE);
1038                         if (unlikely(ret)) {
1039                                 vq_err(vq, "Failed to map iov to sgl\n");
1040                                 goto err_free;
1041                         }
1042                 }
1043
1044                 /*
1045                  * Save the descriptor from vhost_get_vq_desc() to be used to
1046                  * complete the virtio-scsi request in TCM callback context via
1047                  * tcm_vhost_queue_data_in() and tcm_vhost_queue_status()
1048                  */
1049                 cmd->tvc_vq_desc = head;
1050                 /*
1051                  * Dispatch tv_cmd descriptor for cmwq execution in process
1052                  * context provided by tcm_vhost_workqueue.  This also ensures
1053                  * tv_cmd is executed on the same kworker CPU as this vhost
1054                  * thread to gain positive L2 cache locality effects..
1055                  */
1056                 INIT_WORK(&cmd->work, tcm_vhost_submission_work);
1057                 queue_work(tcm_vhost_workqueue, &cmd->work);
1058         }
1059
1060         mutex_unlock(&vq->mutex);
1061         return;
1062
1063 err_free:
1064         vhost_scsi_free_cmd(cmd);
1065 err_cmd:
1066         vhost_scsi_send_bad_target(vs, vq, head, out);
1067         mutex_unlock(&vq->mutex);
1068 }
1069
1070 static void vhost_scsi_ctl_handle_kick(struct vhost_work *work)
1071 {
1072         pr_debug("%s: The handling func for control queue.\n", __func__);
1073 }
1074
1075 static void
1076 tcm_vhost_send_evt(struct vhost_scsi *vs,
1077                    struct tcm_vhost_tpg *tpg,
1078                    struct se_lun *lun,
1079                    u32 event,
1080                    u32 reason)
1081 {
1082         struct tcm_vhost_evt *evt;
1083
1084         evt = tcm_vhost_allocate_evt(vs, event, reason);
1085         if (!evt)
1086                 return;
1087
1088         if (tpg && lun) {
1089                 /* TODO: share lun setup code with virtio-scsi.ko */
1090                 /*
1091                  * Note: evt->event is zeroed when we allocate it and
1092                  * lun[4-7] need to be zero according to virtio-scsi spec.
1093                  */
1094                 evt->event.lun[0] = 0x01;
1095                 evt->event.lun[1] = tpg->tport_tpgt & 0xFF;
1096                 if (lun->unpacked_lun >= 256)
1097                         evt->event.lun[2] = lun->unpacked_lun >> 8 | 0x40 ;
1098                 evt->event.lun[3] = lun->unpacked_lun & 0xFF;
1099         }
1100
1101         llist_add(&evt->list, &vs->vs_event_list);
1102         vhost_work_queue(&vs->dev, &vs->vs_event_work);
1103 }
1104
1105 static void vhost_scsi_evt_handle_kick(struct vhost_work *work)
1106 {
1107         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1108                                                 poll.work);
1109         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1110
1111         mutex_lock(&vq->mutex);
1112         if (!vq->private_data)
1113                 goto out;
1114
1115         if (vs->vs_events_missed)
1116                 tcm_vhost_send_evt(vs, NULL, NULL, VIRTIO_SCSI_T_NO_EVENT, 0);
1117 out:
1118         mutex_unlock(&vq->mutex);
1119 }
1120
1121 static void vhost_scsi_handle_kick(struct vhost_work *work)
1122 {
1123         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1124                                                 poll.work);
1125         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1126
1127         vhost_scsi_handle_vq(vs, vq);
1128 }
1129
1130 static void vhost_scsi_flush_vq(struct vhost_scsi *vs, int index)
1131 {
1132         vhost_poll_flush(&vs->vqs[index].vq.poll);
1133 }
1134
1135 /* Callers must hold dev mutex */
1136 static void vhost_scsi_flush(struct vhost_scsi *vs)
1137 {
1138         struct vhost_scsi_inflight *old_inflight[VHOST_SCSI_MAX_VQ];
1139         int i;
1140
1141         /* Init new inflight and remember the old inflight */
1142         tcm_vhost_init_inflight(vs, old_inflight);
1143
1144         /*
1145          * The inflight->kref was initialized to 1. We decrement it here to
1146          * indicate the start of the flush operation so that it will reach 0
1147          * when all the reqs are finished.
1148          */
1149         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1150                 kref_put(&old_inflight[i]->kref, tcm_vhost_done_inflight);
1151
1152         /* Flush both the vhost poll and vhost work */
1153         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1154                 vhost_scsi_flush_vq(vs, i);
1155         vhost_work_flush(&vs->dev, &vs->vs_completion_work);
1156         vhost_work_flush(&vs->dev, &vs->vs_event_work);
1157
1158         /* Wait for all reqs issued before the flush to be finished */
1159         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1160                 wait_for_completion(&old_inflight[i]->comp);
1161 }
1162
1163 /*
1164  * Called from vhost_scsi_ioctl() context to walk the list of available
1165  * tcm_vhost_tpg with an active struct tcm_vhost_nexus
1166  *
1167  *  The lock nesting rule is:
1168  *    tcm_vhost_mutex -> vs->dev.mutex -> tpg->tv_tpg_mutex -> vq->mutex
1169  */
1170 static int
1171 vhost_scsi_set_endpoint(struct vhost_scsi *vs,
1172                         struct vhost_scsi_target *t)
1173 {
1174         struct tcm_vhost_tport *tv_tport;
1175         struct tcm_vhost_tpg *tpg;
1176         struct tcm_vhost_tpg **vs_tpg;
1177         struct vhost_virtqueue *vq;
1178         int index, ret, i, len;
1179         bool match = false;
1180
1181         mutex_lock(&tcm_vhost_mutex);
1182         mutex_lock(&vs->dev.mutex);
1183
1184         /* Verify that ring has been setup correctly. */
1185         for (index = 0; index < vs->dev.nvqs; ++index) {
1186                 /* Verify that ring has been setup correctly. */
1187                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1188                         ret = -EFAULT;
1189                         goto out;
1190                 }
1191         }
1192
1193         len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET;
1194         vs_tpg = kzalloc(len, GFP_KERNEL);
1195         if (!vs_tpg) {
1196                 ret = -ENOMEM;
1197                 goto out;
1198         }
1199         if (vs->vs_tpg)
1200                 memcpy(vs_tpg, vs->vs_tpg, len);
1201
1202         list_for_each_entry(tpg, &tcm_vhost_list, tv_tpg_list) {
1203                 mutex_lock(&tpg->tv_tpg_mutex);
1204                 if (!tpg->tpg_nexus) {
1205                         mutex_unlock(&tpg->tv_tpg_mutex);
1206                         continue;
1207                 }
1208                 if (tpg->tv_tpg_vhost_count != 0) {
1209                         mutex_unlock(&tpg->tv_tpg_mutex);
1210                         continue;
1211                 }
1212                 tv_tport = tpg->tport;
1213
1214                 if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1215                         if (vs->vs_tpg && vs->vs_tpg[tpg->tport_tpgt]) {
1216                                 kfree(vs_tpg);
1217                                 mutex_unlock(&tpg->tv_tpg_mutex);
1218                                 ret = -EEXIST;
1219                                 goto out;
1220                         }
1221                         tpg->tv_tpg_vhost_count++;
1222                         tpg->vhost_scsi = vs;
1223                         vs_tpg[tpg->tport_tpgt] = tpg;
1224                         smp_mb__after_atomic_inc();
1225                         match = true;
1226                 }
1227                 mutex_unlock(&tpg->tv_tpg_mutex);
1228         }
1229
1230         if (match) {
1231                 memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
1232                        sizeof(vs->vs_vhost_wwpn));
1233                 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1234                         vq = &vs->vqs[i].vq;
1235                         /* Flushing the vhost_work acts as synchronize_rcu */
1236                         mutex_lock(&vq->mutex);
1237                         rcu_assign_pointer(vq->private_data, vs_tpg);
1238                         vhost_init_used(vq);
1239                         mutex_unlock(&vq->mutex);
1240                 }
1241                 ret = 0;
1242         } else {
1243                 ret = -EEXIST;
1244         }
1245
1246         /*
1247          * Act as synchronize_rcu to make sure access to
1248          * old vs->vs_tpg is finished.
1249          */
1250         vhost_scsi_flush(vs);
1251         kfree(vs->vs_tpg);
1252         vs->vs_tpg = vs_tpg;
1253
1254 out:
1255         mutex_unlock(&vs->dev.mutex);
1256         mutex_unlock(&tcm_vhost_mutex);
1257         return ret;
1258 }
1259
1260 static int
1261 vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
1262                           struct vhost_scsi_target *t)
1263 {
1264         struct tcm_vhost_tport *tv_tport;
1265         struct tcm_vhost_tpg *tpg;
1266         struct vhost_virtqueue *vq;
1267         bool match = false;
1268         int index, ret, i;
1269         u8 target;
1270
1271         mutex_lock(&tcm_vhost_mutex);
1272         mutex_lock(&vs->dev.mutex);
1273         /* Verify that ring has been setup correctly. */
1274         for (index = 0; index < vs->dev.nvqs; ++index) {
1275                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1276                         ret = -EFAULT;
1277                         goto err_dev;
1278                 }
1279         }
1280
1281         if (!vs->vs_tpg) {
1282                 ret = 0;
1283                 goto err_dev;
1284         }
1285
1286         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1287                 target = i;
1288                 tpg = vs->vs_tpg[target];
1289                 if (!tpg)
1290                         continue;
1291
1292                 mutex_lock(&tpg->tv_tpg_mutex);
1293                 tv_tport = tpg->tport;
1294                 if (!tv_tport) {
1295                         ret = -ENODEV;
1296                         goto err_tpg;
1297                 }
1298
1299                 if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1300                         pr_warn("tv_tport->tport_name: %s, tpg->tport_tpgt: %hu"
1301                                 " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
1302                                 tv_tport->tport_name, tpg->tport_tpgt,
1303                                 t->vhost_wwpn, t->vhost_tpgt);
1304                         ret = -EINVAL;
1305                         goto err_tpg;
1306                 }
1307                 tpg->tv_tpg_vhost_count--;
1308                 tpg->vhost_scsi = NULL;
1309                 vs->vs_tpg[target] = NULL;
1310                 match = true;
1311                 mutex_unlock(&tpg->tv_tpg_mutex);
1312         }
1313         if (match) {
1314                 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1315                         vq = &vs->vqs[i].vq;
1316                         /* Flushing the vhost_work acts as synchronize_rcu */
1317                         mutex_lock(&vq->mutex);
1318                         rcu_assign_pointer(vq->private_data, NULL);
1319                         mutex_unlock(&vq->mutex);
1320                 }
1321         }
1322         /*
1323          * Act as synchronize_rcu to make sure access to
1324          * old vs->vs_tpg is finished.
1325          */
1326         vhost_scsi_flush(vs);
1327         kfree(vs->vs_tpg);
1328         vs->vs_tpg = NULL;
1329         WARN_ON(vs->vs_events_nr);
1330         mutex_unlock(&vs->dev.mutex);
1331         mutex_unlock(&tcm_vhost_mutex);
1332         return 0;
1333
1334 err_tpg:
1335         mutex_unlock(&tpg->tv_tpg_mutex);
1336 err_dev:
1337         mutex_unlock(&vs->dev.mutex);
1338         mutex_unlock(&tcm_vhost_mutex);
1339         return ret;
1340 }
1341
1342 static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features)
1343 {
1344         if (features & ~VHOST_SCSI_FEATURES)
1345                 return -EOPNOTSUPP;
1346
1347         mutex_lock(&vs->dev.mutex);
1348         if ((features & (1 << VHOST_F_LOG_ALL)) &&
1349             !vhost_log_access_ok(&vs->dev)) {
1350                 mutex_unlock(&vs->dev.mutex);
1351                 return -EFAULT;
1352         }
1353         vs->dev.acked_features = features;
1354         smp_wmb();
1355         vhost_scsi_flush(vs);
1356         mutex_unlock(&vs->dev.mutex);
1357         return 0;
1358 }
1359
1360 static int vhost_scsi_open(struct inode *inode, struct file *f)
1361 {
1362         struct vhost_scsi *vs;
1363         struct vhost_virtqueue **vqs;
1364         int r, i;
1365
1366         vs = kzalloc(sizeof(*vs), GFP_KERNEL);
1367         if (!vs)
1368                 return -ENOMEM;
1369
1370         vqs = kmalloc(VHOST_SCSI_MAX_VQ * sizeof(*vqs), GFP_KERNEL);
1371         if (!vqs) {
1372                 kfree(vs);
1373                 return -ENOMEM;
1374         }
1375
1376         vhost_work_init(&vs->vs_completion_work, vhost_scsi_complete_cmd_work);
1377         vhost_work_init(&vs->vs_event_work, tcm_vhost_evt_work);
1378
1379         vs->vs_events_nr = 0;
1380         vs->vs_events_missed = false;
1381
1382         vqs[VHOST_SCSI_VQ_CTL] = &vs->vqs[VHOST_SCSI_VQ_CTL].vq;
1383         vqs[VHOST_SCSI_VQ_EVT] = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1384         vs->vqs[VHOST_SCSI_VQ_CTL].vq.handle_kick = vhost_scsi_ctl_handle_kick;
1385         vs->vqs[VHOST_SCSI_VQ_EVT].vq.handle_kick = vhost_scsi_evt_handle_kick;
1386         for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++) {
1387                 vqs[i] = &vs->vqs[i].vq;
1388                 vs->vqs[i].vq.handle_kick = vhost_scsi_handle_kick;
1389         }
1390         r = vhost_dev_init(&vs->dev, vqs, VHOST_SCSI_MAX_VQ);
1391
1392         tcm_vhost_init_inflight(vs, NULL);
1393
1394         if (r < 0) {
1395                 kfree(vqs);
1396                 kfree(vs);
1397                 return r;
1398         }
1399
1400         f->private_data = vs;
1401         return 0;
1402 }
1403
1404 static int vhost_scsi_release(struct inode *inode, struct file *f)
1405 {
1406         struct vhost_scsi *vs = f->private_data;
1407         struct vhost_scsi_target t;
1408
1409         mutex_lock(&vs->dev.mutex);
1410         memcpy(t.vhost_wwpn, vs->vs_vhost_wwpn, sizeof(t.vhost_wwpn));
1411         mutex_unlock(&vs->dev.mutex);
1412         vhost_scsi_clear_endpoint(vs, &t);
1413         vhost_dev_stop(&vs->dev);
1414         vhost_dev_cleanup(&vs->dev, false);
1415         /* Jobs can re-queue themselves in evt kick handler. Do extra flush. */
1416         vhost_scsi_flush(vs);
1417         kfree(vs->dev.vqs);
1418         kfree(vs);
1419         return 0;
1420 }
1421
1422 static long
1423 vhost_scsi_ioctl(struct file *f,
1424                  unsigned int ioctl,
1425                  unsigned long arg)
1426 {
1427         struct vhost_scsi *vs = f->private_data;
1428         struct vhost_scsi_target backend;
1429         void __user *argp = (void __user *)arg;
1430         u64 __user *featurep = argp;
1431         u32 __user *eventsp = argp;
1432         u32 events_missed;
1433         u64 features;
1434         int r, abi_version = VHOST_SCSI_ABI_VERSION;
1435         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1436
1437         switch (ioctl) {
1438         case VHOST_SCSI_SET_ENDPOINT:
1439                 if (copy_from_user(&backend, argp, sizeof backend))
1440                         return -EFAULT;
1441                 if (backend.reserved != 0)
1442                         return -EOPNOTSUPP;
1443
1444                 return vhost_scsi_set_endpoint(vs, &backend);
1445         case VHOST_SCSI_CLEAR_ENDPOINT:
1446                 if (copy_from_user(&backend, argp, sizeof backend))
1447                         return -EFAULT;
1448                 if (backend.reserved != 0)
1449                         return -EOPNOTSUPP;
1450
1451                 return vhost_scsi_clear_endpoint(vs, &backend);
1452         case VHOST_SCSI_GET_ABI_VERSION:
1453                 if (copy_to_user(argp, &abi_version, sizeof abi_version))
1454                         return -EFAULT;
1455                 return 0;
1456         case VHOST_SCSI_SET_EVENTS_MISSED:
1457                 if (get_user(events_missed, eventsp))
1458                         return -EFAULT;
1459                 mutex_lock(&vq->mutex);
1460                 vs->vs_events_missed = events_missed;
1461                 mutex_unlock(&vq->mutex);
1462                 return 0;
1463         case VHOST_SCSI_GET_EVENTS_MISSED:
1464                 mutex_lock(&vq->mutex);
1465                 events_missed = vs->vs_events_missed;
1466                 mutex_unlock(&vq->mutex);
1467                 if (put_user(events_missed, eventsp))
1468                         return -EFAULT;
1469                 return 0;
1470         case VHOST_GET_FEATURES:
1471                 features = VHOST_SCSI_FEATURES;
1472                 if (copy_to_user(featurep, &features, sizeof features))
1473                         return -EFAULT;
1474                 return 0;
1475         case VHOST_SET_FEATURES:
1476                 if (copy_from_user(&features, featurep, sizeof features))
1477                         return -EFAULT;
1478                 return vhost_scsi_set_features(vs, features);
1479         default:
1480                 mutex_lock(&vs->dev.mutex);
1481                 r = vhost_dev_ioctl(&vs->dev, ioctl, argp);
1482                 /* TODO: flush backend after dev ioctl. */
1483                 if (r == -ENOIOCTLCMD)
1484                         r = vhost_vring_ioctl(&vs->dev, ioctl, argp);
1485                 mutex_unlock(&vs->dev.mutex);
1486                 return r;
1487         }
1488 }
1489
1490 #ifdef CONFIG_COMPAT
1491 static long vhost_scsi_compat_ioctl(struct file *f, unsigned int ioctl,
1492                                 unsigned long arg)
1493 {
1494         return vhost_scsi_ioctl(f, ioctl, (unsigned long)compat_ptr(arg));
1495 }
1496 #endif
1497
1498 static const struct file_operations vhost_scsi_fops = {
1499         .owner          = THIS_MODULE,
1500         .release        = vhost_scsi_release,
1501         .unlocked_ioctl = vhost_scsi_ioctl,
1502 #ifdef CONFIG_COMPAT
1503         .compat_ioctl   = vhost_scsi_compat_ioctl,
1504 #endif
1505         .open           = vhost_scsi_open,
1506         .llseek         = noop_llseek,
1507 };
1508
1509 static struct miscdevice vhost_scsi_misc = {
1510         MISC_DYNAMIC_MINOR,
1511         "vhost-scsi",
1512         &vhost_scsi_fops,
1513 };
1514
1515 static int __init vhost_scsi_register(void)
1516 {
1517         return misc_register(&vhost_scsi_misc);
1518 }
1519
1520 static int vhost_scsi_deregister(void)
1521 {
1522         return misc_deregister(&vhost_scsi_misc);
1523 }
1524
1525 static char *tcm_vhost_dump_proto_id(struct tcm_vhost_tport *tport)
1526 {
1527         switch (tport->tport_proto_id) {
1528         case SCSI_PROTOCOL_SAS:
1529                 return "SAS";
1530         case SCSI_PROTOCOL_FCP:
1531                 return "FCP";
1532         case SCSI_PROTOCOL_ISCSI:
1533                 return "iSCSI";
1534         default:
1535                 break;
1536         }
1537
1538         return "Unknown";
1539 }
1540
1541 static void
1542 tcm_vhost_do_plug(struct tcm_vhost_tpg *tpg,
1543                   struct se_lun *lun, bool plug)
1544 {
1545
1546         struct vhost_scsi *vs = tpg->vhost_scsi;
1547         struct vhost_virtqueue *vq;
1548         u32 reason;
1549
1550         if (!vs)
1551                 return;
1552
1553         mutex_lock(&vs->dev.mutex);
1554         if (!vhost_has_feature(&vs->dev, VIRTIO_SCSI_F_HOTPLUG)) {
1555                 mutex_unlock(&vs->dev.mutex);
1556                 return;
1557         }
1558
1559         if (plug)
1560                 reason = VIRTIO_SCSI_EVT_RESET_RESCAN;
1561         else
1562                 reason = VIRTIO_SCSI_EVT_RESET_REMOVED;
1563
1564         vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1565         mutex_lock(&vq->mutex);
1566         tcm_vhost_send_evt(vs, tpg, lun,
1567                         VIRTIO_SCSI_T_TRANSPORT_RESET, reason);
1568         mutex_unlock(&vq->mutex);
1569         mutex_unlock(&vs->dev.mutex);
1570 }
1571
1572 static void tcm_vhost_hotplug(struct tcm_vhost_tpg *tpg, struct se_lun *lun)
1573 {
1574         tcm_vhost_do_plug(tpg, lun, true);
1575 }
1576
1577 static void tcm_vhost_hotunplug(struct tcm_vhost_tpg *tpg, struct se_lun *lun)
1578 {
1579         tcm_vhost_do_plug(tpg, lun, false);
1580 }
1581
1582 static int tcm_vhost_port_link(struct se_portal_group *se_tpg,
1583                                struct se_lun *lun)
1584 {
1585         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1586                                 struct tcm_vhost_tpg, se_tpg);
1587
1588         mutex_lock(&tcm_vhost_mutex);
1589
1590         mutex_lock(&tpg->tv_tpg_mutex);
1591         tpg->tv_tpg_port_count++;
1592         mutex_unlock(&tpg->tv_tpg_mutex);
1593
1594         tcm_vhost_hotplug(tpg, lun);
1595
1596         mutex_unlock(&tcm_vhost_mutex);
1597
1598         return 0;
1599 }
1600
1601 static void tcm_vhost_port_unlink(struct se_portal_group *se_tpg,
1602                                   struct se_lun *lun)
1603 {
1604         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1605                                 struct tcm_vhost_tpg, se_tpg);
1606
1607         mutex_lock(&tcm_vhost_mutex);
1608
1609         mutex_lock(&tpg->tv_tpg_mutex);
1610         tpg->tv_tpg_port_count--;
1611         mutex_unlock(&tpg->tv_tpg_mutex);
1612
1613         tcm_vhost_hotunplug(tpg, lun);
1614
1615         mutex_unlock(&tcm_vhost_mutex);
1616 }
1617
1618 static struct se_node_acl *
1619 tcm_vhost_make_nodeacl(struct se_portal_group *se_tpg,
1620                        struct config_group *group,
1621                        const char *name)
1622 {
1623         struct se_node_acl *se_nacl, *se_nacl_new;
1624         struct tcm_vhost_nacl *nacl;
1625         u64 wwpn = 0;
1626         u32 nexus_depth;
1627
1628         /* tcm_vhost_parse_wwn(name, &wwpn, 1) < 0)
1629                 return ERR_PTR(-EINVAL); */
1630         se_nacl_new = tcm_vhost_alloc_fabric_acl(se_tpg);
1631         if (!se_nacl_new)
1632                 return ERR_PTR(-ENOMEM);
1633
1634         nexus_depth = 1;
1635         /*
1636          * se_nacl_new may be released by core_tpg_add_initiator_node_acl()
1637          * when converting a NodeACL from demo mode -> explict
1638          */
1639         se_nacl = core_tpg_add_initiator_node_acl(se_tpg, se_nacl_new,
1640                                 name, nexus_depth);
1641         if (IS_ERR(se_nacl)) {
1642                 tcm_vhost_release_fabric_acl(se_tpg, se_nacl_new);
1643                 return se_nacl;
1644         }
1645         /*
1646          * Locate our struct tcm_vhost_nacl and set the FC Nport WWPN
1647          */
1648         nacl = container_of(se_nacl, struct tcm_vhost_nacl, se_node_acl);
1649         nacl->iport_wwpn = wwpn;
1650
1651         return se_nacl;
1652 }
1653
1654 static void tcm_vhost_drop_nodeacl(struct se_node_acl *se_acl)
1655 {
1656         struct tcm_vhost_nacl *nacl = container_of(se_acl,
1657                                 struct tcm_vhost_nacl, se_node_acl);
1658         core_tpg_del_initiator_node_acl(se_acl->se_tpg, se_acl, 1);
1659         kfree(nacl);
1660 }
1661
1662 static int tcm_vhost_make_nexus(struct tcm_vhost_tpg *tpg,
1663                                 const char *name)
1664 {
1665         struct se_portal_group *se_tpg;
1666         struct tcm_vhost_nexus *tv_nexus;
1667
1668         mutex_lock(&tpg->tv_tpg_mutex);
1669         if (tpg->tpg_nexus) {
1670                 mutex_unlock(&tpg->tv_tpg_mutex);
1671                 pr_debug("tpg->tpg_nexus already exists\n");
1672                 return -EEXIST;
1673         }
1674         se_tpg = &tpg->se_tpg;
1675
1676         tv_nexus = kzalloc(sizeof(struct tcm_vhost_nexus), GFP_KERNEL);
1677         if (!tv_nexus) {
1678                 mutex_unlock(&tpg->tv_tpg_mutex);
1679                 pr_err("Unable to allocate struct tcm_vhost_nexus\n");
1680                 return -ENOMEM;
1681         }
1682         /*
1683          *  Initialize the struct se_session pointer
1684          */
1685         tv_nexus->tvn_se_sess = transport_init_session();
1686         if (IS_ERR(tv_nexus->tvn_se_sess)) {
1687                 mutex_unlock(&tpg->tv_tpg_mutex);
1688                 kfree(tv_nexus);
1689                 return -ENOMEM;
1690         }
1691         /*
1692          * Since we are running in 'demo mode' this call with generate a
1693          * struct se_node_acl for the tcm_vhost struct se_portal_group with
1694          * the SCSI Initiator port name of the passed configfs group 'name'.
1695          */
1696         tv_nexus->tvn_se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
1697                                 se_tpg, (unsigned char *)name);
1698         if (!tv_nexus->tvn_se_sess->se_node_acl) {
1699                 mutex_unlock(&tpg->tv_tpg_mutex);
1700                 pr_debug("core_tpg_check_initiator_node_acl() failed"
1701                                 " for %s\n", name);
1702                 transport_free_session(tv_nexus->tvn_se_sess);
1703                 kfree(tv_nexus);
1704                 return -ENOMEM;
1705         }
1706         /*
1707          * Now register the TCM vhost virtual I_T Nexus as active with the
1708          * call to __transport_register_session()
1709          */
1710         __transport_register_session(se_tpg, tv_nexus->tvn_se_sess->se_node_acl,
1711                         tv_nexus->tvn_se_sess, tv_nexus);
1712         tpg->tpg_nexus = tv_nexus;
1713
1714         mutex_unlock(&tpg->tv_tpg_mutex);
1715         return 0;
1716 }
1717
1718 static int tcm_vhost_drop_nexus(struct tcm_vhost_tpg *tpg)
1719 {
1720         struct se_session *se_sess;
1721         struct tcm_vhost_nexus *tv_nexus;
1722
1723         mutex_lock(&tpg->tv_tpg_mutex);
1724         tv_nexus = tpg->tpg_nexus;
1725         if (!tv_nexus) {
1726                 mutex_unlock(&tpg->tv_tpg_mutex);
1727                 return -ENODEV;
1728         }
1729
1730         se_sess = tv_nexus->tvn_se_sess;
1731         if (!se_sess) {
1732                 mutex_unlock(&tpg->tv_tpg_mutex);
1733                 return -ENODEV;
1734         }
1735
1736         if (tpg->tv_tpg_port_count != 0) {
1737                 mutex_unlock(&tpg->tv_tpg_mutex);
1738                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
1739                         " active TPG port count: %d\n",
1740                         tpg->tv_tpg_port_count);
1741                 return -EBUSY;
1742         }
1743
1744         if (tpg->tv_tpg_vhost_count != 0) {
1745                 mutex_unlock(&tpg->tv_tpg_mutex);
1746                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
1747                         " active TPG vhost count: %d\n",
1748                         tpg->tv_tpg_vhost_count);
1749                 return -EBUSY;
1750         }
1751
1752         pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated"
1753                 " %s Initiator Port: %s\n", tcm_vhost_dump_proto_id(tpg->tport),
1754                 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1755         /*
1756          * Release the SCSI I_T Nexus to the emulated vhost Target Port
1757          */
1758         transport_deregister_session(tv_nexus->tvn_se_sess);
1759         tpg->tpg_nexus = NULL;
1760         mutex_unlock(&tpg->tv_tpg_mutex);
1761
1762         kfree(tv_nexus);
1763         return 0;
1764 }
1765
1766 static ssize_t tcm_vhost_tpg_show_nexus(struct se_portal_group *se_tpg,
1767                                         char *page)
1768 {
1769         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1770                                 struct tcm_vhost_tpg, se_tpg);
1771         struct tcm_vhost_nexus *tv_nexus;
1772         ssize_t ret;
1773
1774         mutex_lock(&tpg->tv_tpg_mutex);
1775         tv_nexus = tpg->tpg_nexus;
1776         if (!tv_nexus) {
1777                 mutex_unlock(&tpg->tv_tpg_mutex);
1778                 return -ENODEV;
1779         }
1780         ret = snprintf(page, PAGE_SIZE, "%s\n",
1781                         tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1782         mutex_unlock(&tpg->tv_tpg_mutex);
1783
1784         return ret;
1785 }
1786
1787 static ssize_t tcm_vhost_tpg_store_nexus(struct se_portal_group *se_tpg,
1788                                          const char *page,
1789                                          size_t count)
1790 {
1791         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1792                                 struct tcm_vhost_tpg, se_tpg);
1793         struct tcm_vhost_tport *tport_wwn = tpg->tport;
1794         unsigned char i_port[TCM_VHOST_NAMELEN], *ptr, *port_ptr;
1795         int ret;
1796         /*
1797          * Shutdown the active I_T nexus if 'NULL' is passed..
1798          */
1799         if (!strncmp(page, "NULL", 4)) {
1800                 ret = tcm_vhost_drop_nexus(tpg);
1801                 return (!ret) ? count : ret;
1802         }
1803         /*
1804          * Otherwise make sure the passed virtual Initiator port WWN matches
1805          * the fabric protocol_id set in tcm_vhost_make_tport(), and call
1806          * tcm_vhost_make_nexus().
1807          */
1808         if (strlen(page) >= TCM_VHOST_NAMELEN) {
1809                 pr_err("Emulated NAA Sas Address: %s, exceeds"
1810                                 " max: %d\n", page, TCM_VHOST_NAMELEN);
1811                 return -EINVAL;
1812         }
1813         snprintf(&i_port[0], TCM_VHOST_NAMELEN, "%s", page);
1814
1815         ptr = strstr(i_port, "naa.");
1816         if (ptr) {
1817                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
1818                         pr_err("Passed SAS Initiator Port %s does not"
1819                                 " match target port protoid: %s\n", i_port,
1820                                 tcm_vhost_dump_proto_id(tport_wwn));
1821                         return -EINVAL;
1822                 }
1823                 port_ptr = &i_port[0];
1824                 goto check_newline;
1825         }
1826         ptr = strstr(i_port, "fc.");
1827         if (ptr) {
1828                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
1829                         pr_err("Passed FCP Initiator Port %s does not"
1830                                 " match target port protoid: %s\n", i_port,
1831                                 tcm_vhost_dump_proto_id(tport_wwn));
1832                         return -EINVAL;
1833                 }
1834                 port_ptr = &i_port[3]; /* Skip over "fc." */
1835                 goto check_newline;
1836         }
1837         ptr = strstr(i_port, "iqn.");
1838         if (ptr) {
1839                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
1840                         pr_err("Passed iSCSI Initiator Port %s does not"
1841                                 " match target port protoid: %s\n", i_port,
1842                                 tcm_vhost_dump_proto_id(tport_wwn));
1843                         return -EINVAL;
1844                 }
1845                 port_ptr = &i_port[0];
1846                 goto check_newline;
1847         }
1848         pr_err("Unable to locate prefix for emulated Initiator Port:"
1849                         " %s\n", i_port);
1850         return -EINVAL;
1851         /*
1852          * Clear any trailing newline for the NAA WWN
1853          */
1854 check_newline:
1855         if (i_port[strlen(i_port)-1] == '\n')
1856                 i_port[strlen(i_port)-1] = '\0';
1857
1858         ret = tcm_vhost_make_nexus(tpg, port_ptr);
1859         if (ret < 0)
1860                 return ret;
1861
1862         return count;
1863 }
1864
1865 TF_TPG_BASE_ATTR(tcm_vhost, nexus, S_IRUGO | S_IWUSR);
1866
1867 static struct configfs_attribute *tcm_vhost_tpg_attrs[] = {
1868         &tcm_vhost_tpg_nexus.attr,
1869         NULL,
1870 };
1871
1872 static struct se_portal_group *
1873 tcm_vhost_make_tpg(struct se_wwn *wwn,
1874                    struct config_group *group,
1875                    const char *name)
1876 {
1877         struct tcm_vhost_tport *tport = container_of(wwn,
1878                         struct tcm_vhost_tport, tport_wwn);
1879
1880         struct tcm_vhost_tpg *tpg;
1881         unsigned long tpgt;
1882         int ret;
1883
1884         if (strstr(name, "tpgt_") != name)
1885                 return ERR_PTR(-EINVAL);
1886         if (kstrtoul(name + 5, 10, &tpgt) || tpgt > UINT_MAX)
1887                 return ERR_PTR(-EINVAL);
1888
1889         tpg = kzalloc(sizeof(struct tcm_vhost_tpg), GFP_KERNEL);
1890         if (!tpg) {
1891                 pr_err("Unable to allocate struct tcm_vhost_tpg");
1892                 return ERR_PTR(-ENOMEM);
1893         }
1894         mutex_init(&tpg->tv_tpg_mutex);
1895         INIT_LIST_HEAD(&tpg->tv_tpg_list);
1896         tpg->tport = tport;
1897         tpg->tport_tpgt = tpgt;
1898
1899         ret = core_tpg_register(&tcm_vhost_fabric_configfs->tf_ops, wwn,
1900                                 &tpg->se_tpg, tpg, TRANSPORT_TPG_TYPE_NORMAL);
1901         if (ret < 0) {
1902                 kfree(tpg);
1903                 return NULL;
1904         }
1905         mutex_lock(&tcm_vhost_mutex);
1906         list_add_tail(&tpg->tv_tpg_list, &tcm_vhost_list);
1907         mutex_unlock(&tcm_vhost_mutex);
1908
1909         return &tpg->se_tpg;
1910 }
1911
1912 static void tcm_vhost_drop_tpg(struct se_portal_group *se_tpg)
1913 {
1914         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1915                                 struct tcm_vhost_tpg, se_tpg);
1916
1917         mutex_lock(&tcm_vhost_mutex);
1918         list_del(&tpg->tv_tpg_list);
1919         mutex_unlock(&tcm_vhost_mutex);
1920         /*
1921          * Release the virtual I_T Nexus for this vhost TPG
1922          */
1923         tcm_vhost_drop_nexus(tpg);
1924         /*
1925          * Deregister the se_tpg from TCM..
1926          */
1927         core_tpg_deregister(se_tpg);
1928         kfree(tpg);
1929 }
1930
1931 static struct se_wwn *
1932 tcm_vhost_make_tport(struct target_fabric_configfs *tf,
1933                      struct config_group *group,
1934                      const char *name)
1935 {
1936         struct tcm_vhost_tport *tport;
1937         char *ptr;
1938         u64 wwpn = 0;
1939         int off = 0;
1940
1941         /* if (tcm_vhost_parse_wwn(name, &wwpn, 1) < 0)
1942                 return ERR_PTR(-EINVAL); */
1943
1944         tport = kzalloc(sizeof(struct tcm_vhost_tport), GFP_KERNEL);
1945         if (!tport) {
1946                 pr_err("Unable to allocate struct tcm_vhost_tport");
1947                 return ERR_PTR(-ENOMEM);
1948         }
1949         tport->tport_wwpn = wwpn;
1950         /*
1951          * Determine the emulated Protocol Identifier and Target Port Name
1952          * based on the incoming configfs directory name.
1953          */
1954         ptr = strstr(name, "naa.");
1955         if (ptr) {
1956                 tport->tport_proto_id = SCSI_PROTOCOL_SAS;
1957                 goto check_len;
1958         }
1959         ptr = strstr(name, "fc.");
1960         if (ptr) {
1961                 tport->tport_proto_id = SCSI_PROTOCOL_FCP;
1962                 off = 3; /* Skip over "fc." */
1963                 goto check_len;
1964         }
1965         ptr = strstr(name, "iqn.");
1966         if (ptr) {
1967                 tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
1968                 goto check_len;
1969         }
1970
1971         pr_err("Unable to locate prefix for emulated Target Port:"
1972                         " %s\n", name);
1973         kfree(tport);
1974         return ERR_PTR(-EINVAL);
1975
1976 check_len:
1977         if (strlen(name) >= TCM_VHOST_NAMELEN) {
1978                 pr_err("Emulated %s Address: %s, exceeds"
1979                         " max: %d\n", name, tcm_vhost_dump_proto_id(tport),
1980                         TCM_VHOST_NAMELEN);
1981                 kfree(tport);
1982                 return ERR_PTR(-EINVAL);
1983         }
1984         snprintf(&tport->tport_name[0], TCM_VHOST_NAMELEN, "%s", &name[off]);
1985
1986         pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target"
1987                 " %s Address: %s\n", tcm_vhost_dump_proto_id(tport), name);
1988
1989         return &tport->tport_wwn;
1990 }
1991
1992 static void tcm_vhost_drop_tport(struct se_wwn *wwn)
1993 {
1994         struct tcm_vhost_tport *tport = container_of(wwn,
1995                                 struct tcm_vhost_tport, tport_wwn);
1996
1997         pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target"
1998                 " %s Address: %s\n", tcm_vhost_dump_proto_id(tport),
1999                 tport->tport_name);
2000
2001         kfree(tport);
2002 }
2003
2004 static ssize_t
2005 tcm_vhost_wwn_show_attr_version(struct target_fabric_configfs *tf,
2006                                 char *page)
2007 {
2008         return sprintf(page, "TCM_VHOST fabric module %s on %s/%s"
2009                 "on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname,
2010                 utsname()->machine);
2011 }
2012
2013 TF_WWN_ATTR_RO(tcm_vhost, version);
2014
2015 static struct configfs_attribute *tcm_vhost_wwn_attrs[] = {
2016         &tcm_vhost_wwn_version.attr,
2017         NULL,
2018 };
2019
2020 static struct target_core_fabric_ops tcm_vhost_ops = {
2021         .get_fabric_name                = tcm_vhost_get_fabric_name,
2022         .get_fabric_proto_ident         = tcm_vhost_get_fabric_proto_ident,
2023         .tpg_get_wwn                    = tcm_vhost_get_fabric_wwn,
2024         .tpg_get_tag                    = tcm_vhost_get_tag,
2025         .tpg_get_default_depth          = tcm_vhost_get_default_depth,
2026         .tpg_get_pr_transport_id        = tcm_vhost_get_pr_transport_id,
2027         .tpg_get_pr_transport_id_len    = tcm_vhost_get_pr_transport_id_len,
2028         .tpg_parse_pr_out_transport_id  = tcm_vhost_parse_pr_out_transport_id,
2029         .tpg_check_demo_mode            = tcm_vhost_check_true,
2030         .tpg_check_demo_mode_cache      = tcm_vhost_check_true,
2031         .tpg_check_demo_mode_write_protect = tcm_vhost_check_false,
2032         .tpg_check_prod_mode_write_protect = tcm_vhost_check_false,
2033         .tpg_alloc_fabric_acl           = tcm_vhost_alloc_fabric_acl,
2034         .tpg_release_fabric_acl         = tcm_vhost_release_fabric_acl,
2035         .tpg_get_inst_index             = tcm_vhost_tpg_get_inst_index,
2036         .release_cmd                    = tcm_vhost_release_cmd,
2037         .check_stop_free                = vhost_scsi_check_stop_free,
2038         .shutdown_session               = tcm_vhost_shutdown_session,
2039         .close_session                  = tcm_vhost_close_session,
2040         .sess_get_index                 = tcm_vhost_sess_get_index,
2041         .sess_get_initiator_sid         = NULL,
2042         .write_pending                  = tcm_vhost_write_pending,
2043         .write_pending_status           = tcm_vhost_write_pending_status,
2044         .set_default_node_attributes    = tcm_vhost_set_default_node_attrs,
2045         .get_task_tag                   = tcm_vhost_get_task_tag,
2046         .get_cmd_state                  = tcm_vhost_get_cmd_state,
2047         .queue_data_in                  = tcm_vhost_queue_data_in,
2048         .queue_status                   = tcm_vhost_queue_status,
2049         .queue_tm_rsp                   = tcm_vhost_queue_tm_rsp,
2050         /*
2051          * Setup callers for generic logic in target_core_fabric_configfs.c
2052          */
2053         .fabric_make_wwn                = tcm_vhost_make_tport,
2054         .fabric_drop_wwn                = tcm_vhost_drop_tport,
2055         .fabric_make_tpg                = tcm_vhost_make_tpg,
2056         .fabric_drop_tpg                = tcm_vhost_drop_tpg,
2057         .fabric_post_link               = tcm_vhost_port_link,
2058         .fabric_pre_unlink              = tcm_vhost_port_unlink,
2059         .fabric_make_np                 = NULL,
2060         .fabric_drop_np                 = NULL,
2061         .fabric_make_nodeacl            = tcm_vhost_make_nodeacl,
2062         .fabric_drop_nodeacl            = tcm_vhost_drop_nodeacl,
2063 };
2064
2065 static int tcm_vhost_register_configfs(void)
2066 {
2067         struct target_fabric_configfs *fabric;
2068         int ret;
2069
2070         pr_debug("TCM_VHOST fabric module %s on %s/%s"
2071                 " on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname,
2072                 utsname()->machine);
2073         /*
2074          * Register the top level struct config_item_type with TCM core
2075          */
2076         fabric = target_fabric_configfs_init(THIS_MODULE, "vhost");
2077         if (IS_ERR(fabric)) {
2078                 pr_err("target_fabric_configfs_init() failed\n");
2079                 return PTR_ERR(fabric);
2080         }
2081         /*
2082          * Setup fabric->tf_ops from our local tcm_vhost_ops
2083          */
2084         fabric->tf_ops = tcm_vhost_ops;
2085         /*
2086          * Setup default attribute lists for various fabric->tf_cit_tmpl
2087          */
2088         TF_CIT_TMPL(fabric)->tfc_wwn_cit.ct_attrs = tcm_vhost_wwn_attrs;
2089         TF_CIT_TMPL(fabric)->tfc_tpg_base_cit.ct_attrs = tcm_vhost_tpg_attrs;
2090         TF_CIT_TMPL(fabric)->tfc_tpg_attrib_cit.ct_attrs = NULL;
2091         TF_CIT_TMPL(fabric)->tfc_tpg_param_cit.ct_attrs = NULL;
2092         TF_CIT_TMPL(fabric)->tfc_tpg_np_base_cit.ct_attrs = NULL;
2093         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_base_cit.ct_attrs = NULL;
2094         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_attrib_cit.ct_attrs = NULL;
2095         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_auth_cit.ct_attrs = NULL;
2096         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_param_cit.ct_attrs = NULL;
2097         /*
2098          * Register the fabric for use within TCM
2099          */
2100         ret = target_fabric_configfs_register(fabric);
2101         if (ret < 0) {
2102                 pr_err("target_fabric_configfs_register() failed"
2103                                 " for TCM_VHOST\n");
2104                 return ret;
2105         }
2106         /*
2107          * Setup our local pointer to *fabric
2108          */
2109         tcm_vhost_fabric_configfs = fabric;
2110         pr_debug("TCM_VHOST[0] - Set fabric -> tcm_vhost_fabric_configfs\n");
2111         return 0;
2112 };
2113
2114 static void tcm_vhost_deregister_configfs(void)
2115 {
2116         if (!tcm_vhost_fabric_configfs)
2117                 return;
2118
2119         target_fabric_configfs_deregister(tcm_vhost_fabric_configfs);
2120         tcm_vhost_fabric_configfs = NULL;
2121         pr_debug("TCM_VHOST[0] - Cleared tcm_vhost_fabric_configfs\n");
2122 };
2123
2124 static int __init tcm_vhost_init(void)
2125 {
2126         int ret = -ENOMEM;
2127         /*
2128          * Use our own dedicated workqueue for submitting I/O into
2129          * target core to avoid contention within system_wq.
2130          */
2131         tcm_vhost_workqueue = alloc_workqueue("tcm_vhost", 0, 0);
2132         if (!tcm_vhost_workqueue)
2133                 goto out;
2134
2135         ret = vhost_scsi_register();
2136         if (ret < 0)
2137                 goto out_destroy_workqueue;
2138
2139         ret = tcm_vhost_register_configfs();
2140         if (ret < 0)
2141                 goto out_vhost_scsi_deregister;
2142
2143         return 0;
2144
2145 out_vhost_scsi_deregister:
2146         vhost_scsi_deregister();
2147 out_destroy_workqueue:
2148         destroy_workqueue(tcm_vhost_workqueue);
2149 out:
2150         return ret;
2151 };
2152
2153 static void tcm_vhost_exit(void)
2154 {
2155         tcm_vhost_deregister_configfs();
2156         vhost_scsi_deregister();
2157         destroy_workqueue(tcm_vhost_workqueue);
2158 };
2159
2160 MODULE_DESCRIPTION("VHOST_SCSI series fabric driver");
2161 MODULE_ALIAS("tcm_vhost");
2162 MODULE_LICENSE("GPL");
2163 module_init(tcm_vhost_init);
2164 module_exit(tcm_vhost_exit);