Pileus Git - ~andy/linux/blob - drivers/vhost/tcm_vhost.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_net.h> /* TODO vhost.h currently depends on this */
  49 #include <linux/virtio_scsi.h>
  50
  51 #include "vhost.c"
  52 #include "vhost.h"
  53 #include "tcm_vhost.h"
  54
  55 enum {
  56         VHOST_SCSI_VQ_CTL = 0,
  57         VHOST_SCSI_VQ_EVT = 1,
  58         VHOST_SCSI_VQ_IO = 2,
  59 };
  60
  61 struct vhost_scsi {
  62         struct tcm_vhost_tpg *vs_tpg;   /* Protected by vhost_scsi->dev.mutex */
  63         struct vhost_dev dev;
  64         struct vhost_virtqueue vqs[3];
  65
  66         struct vhost_work vs_completion_work; /* cmd completion work item */
  67         struct list_head vs_completion_list;  /* cmd completion queue */
  68         spinlock_t vs_completion_lock;        /* protects s_completion_list */
  69 };
  70
  71 /* Local pointer to allocated TCM configfs fabric module */
  72 static struct target_fabric_configfs *tcm_vhost_fabric_configfs;
  73
  74 static struct workqueue_struct *tcm_vhost_workqueue;
  75
  76 /* Global spinlock to protect tcm_vhost TPG list for vhost IOCTL access */
  77 static DEFINE_MUTEX(tcm_vhost_mutex);
  78 static LIST_HEAD(tcm_vhost_list);
  79
  80 static int tcm_vhost_check_true(struct se_portal_group *se_tpg)
  81 {
  82         return 1;
  83 }
  84
  85 static int tcm_vhost_check_false(struct se_portal_group *se_tpg)
  86 {
  87         return 0;
  88 }
  89
  90 static char *tcm_vhost_get_fabric_name(void)
  91 {
  92         return "vhost";
  93 }
  94
  95 static u8 tcm_vhost_get_fabric_proto_ident(struct se_portal_group *se_tpg)
  96 {
  97         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
  98                                 struct tcm_vhost_tpg, se_tpg);
  99         struct tcm_vhost_tport *tport = tpg->tport;
 100
 101         switch (tport->tport_proto_id) {
 102         case SCSI_PROTOCOL_SAS:
 103                 return sas_get_fabric_proto_ident(se_tpg);
 104         case SCSI_PROTOCOL_FCP:
 105                 return fc_get_fabric_proto_ident(se_tpg);
 106         case SCSI_PROTOCOL_ISCSI:
 107                 return iscsi_get_fabric_proto_ident(se_tpg);
 108         default:
 109                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 110                         " SAS emulation\n", tport->tport_proto_id);
 111                 break;
 112         }
 113
 114         return sas_get_fabric_proto_ident(se_tpg);
 115 }
 116
 117 static char *tcm_vhost_get_fabric_wwn(struct se_portal_group *se_tpg)
 118 {
 119         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 120                                 struct tcm_vhost_tpg, se_tpg);
 121         struct tcm_vhost_tport *tport = tpg->tport;
 122
 123         return &tport->tport_name[0];
 124 }
 125
 126 static u16 tcm_vhost_get_tag(struct se_portal_group *se_tpg)
 127 {
 128         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 129                                 struct tcm_vhost_tpg, se_tpg);
 130         return tpg->tport_tpgt;
 131 }
 132
 133 static u32 tcm_vhost_get_default_depth(struct se_portal_group *se_tpg)
 134 {
 135         return 1;
 136 }
 137
 138 static u32 tcm_vhost_get_pr_transport_id(struct se_portal_group *se_tpg,
 139         struct se_node_acl *se_nacl,
 140         struct t10_pr_registration *pr_reg,
 141         int *format_code,
 142         unsigned char *buf)
 143 {
 144         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 145                                 struct tcm_vhost_tpg, se_tpg);
 146         struct tcm_vhost_tport *tport = tpg->tport;
 147
 148         switch (tport->tport_proto_id) {
 149         case SCSI_PROTOCOL_SAS:
 150                 return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 151                                         format_code, buf);
 152         case SCSI_PROTOCOL_FCP:
 153                 return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 154                                         format_code, buf);
 155         case SCSI_PROTOCOL_ISCSI:
 156                 return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 157                                         format_code, buf);
 158         default:
 159                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 160                         " SAS emulation\n", tport->tport_proto_id);
 161                 break;
 162         }
 163
 164         return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 165                         format_code, buf);
 166 }
 167
 168 static u32 tcm_vhost_get_pr_transport_id_len(struct se_portal_group *se_tpg,
 169         struct se_node_acl *se_nacl,
 170         struct t10_pr_registration *pr_reg,
 171         int *format_code)
 172 {
 173         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 174                                 struct tcm_vhost_tpg, se_tpg);
 175         struct tcm_vhost_tport *tport = tpg->tport;
 176
 177         switch (tport->tport_proto_id) {
 178         case SCSI_PROTOCOL_SAS:
 179                 return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 180                                         format_code);
 181         case SCSI_PROTOCOL_FCP:
 182                 return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 183                                         format_code);
 184         case SCSI_PROTOCOL_ISCSI:
 185                 return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 186                                         format_code);
 187         default:
 188                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 189                         " SAS emulation\n", tport->tport_proto_id);
 190                 break;
 191         }
 192
 193         return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 194                         format_code);
 195 }
 196
 197 static char *tcm_vhost_parse_pr_out_transport_id(struct se_portal_group *se_tpg,
 198         const char *buf,
 199         u32 *out_tid_len,
 200         char **port_nexus_ptr)
 201 {
 202         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 203                                 struct tcm_vhost_tpg, se_tpg);
 204         struct tcm_vhost_tport *tport = tpg->tport;
 205
 206         switch (tport->tport_proto_id) {
 207         case SCSI_PROTOCOL_SAS:
 208                 return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 209                                         port_nexus_ptr);
 210         case SCSI_PROTOCOL_FCP:
 211                 return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 212                                         port_nexus_ptr);
 213         case SCSI_PROTOCOL_ISCSI:
 214                 return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 215                                         port_nexus_ptr);
 216         default:
 217                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 218                         " SAS emulation\n", tport->tport_proto_id);
 219                 break;
 220         }
 221
 222         return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 223                         port_nexus_ptr);
 224 }
 225
 226 static struct se_node_acl *tcm_vhost_alloc_fabric_acl(
 227         struct se_portal_group *se_tpg)
 228 {
 229         struct tcm_vhost_nacl *nacl;
 230
 231         nacl = kzalloc(sizeof(struct tcm_vhost_nacl), GFP_KERNEL);
 232         if (!nacl) {
 233                 pr_err("Unable to allocate struct tcm_vhost_nacl\n");
 234                 return NULL;
 235         }
 236
 237         return &nacl->se_node_acl;
 238 }
 239
 240 static void tcm_vhost_release_fabric_acl(struct se_portal_group *se_tpg,
 241         struct se_node_acl *se_nacl)
 242 {
 243         struct tcm_vhost_nacl *nacl = container_of(se_nacl,
 244                         struct tcm_vhost_nacl, se_node_acl);
 245         kfree(nacl);
 246 }
 247
 248 static u32 tcm_vhost_tpg_get_inst_index(struct se_portal_group *se_tpg)
 249 {
 250         return 1;
 251 }
 252
 253 static void tcm_vhost_release_cmd(struct se_cmd *se_cmd)
 254 {
 255         return;
 256 }
 257
 258 static int tcm_vhost_shutdown_session(struct se_session *se_sess)
 259 {
 260         return 0;
 261 }
 262
 263 static void tcm_vhost_close_session(struct se_session *se_sess)
 264 {
 265         return;
 266 }
 267
 268 static u32 tcm_vhost_sess_get_index(struct se_session *se_sess)
 269 {
 270         return 0;
 271 }
 272
 273 static int tcm_vhost_write_pending(struct se_cmd *se_cmd)
 274 {
 275         /* Go ahead and process the write immediately */
 276         target_execute_cmd(se_cmd);
 277         return 0;
 278 }
 279
 280 static int tcm_vhost_write_pending_status(struct se_cmd *se_cmd)
 281 {
 282         return 0;
 283 }
 284
 285 static void tcm_vhost_set_default_node_attrs(struct se_node_acl *nacl)
 286 {
 287         return;
 288 }
 289
 290 static u32 tcm_vhost_get_task_tag(struct se_cmd *se_cmd)
 291 {
 292         return 0;
 293 }
 294
 295 static int tcm_vhost_get_cmd_state(struct se_cmd *se_cmd)
 296 {
 297         return 0;
 298 }
 299
 300 static void vhost_scsi_complete_cmd(struct tcm_vhost_cmd *tv_cmd)
 301 {
 302         struct vhost_scsi *vs = tv_cmd->tvc_vhost;
 303
 304         spin_lock_bh(&vs->vs_completion_lock);
 305         list_add_tail(&tv_cmd->tvc_completion_list, &vs->vs_completion_list);
 306         spin_unlock_bh(&vs->vs_completion_lock);
 307
 308         vhost_work_queue(&vs->dev, &vs->vs_completion_work);
 309 }
 310
 311 static int tcm_vhost_queue_data_in(struct se_cmd *se_cmd)
 312 {
 313         struct tcm_vhost_cmd *tv_cmd = container_of(se_cmd,
 314                                 struct tcm_vhost_cmd, tvc_se_cmd);
 315         vhost_scsi_complete_cmd(tv_cmd);
 316         return 0;
 317 }
 318
 319 static int tcm_vhost_queue_status(struct se_cmd *se_cmd)
 320 {
 321         struct tcm_vhost_cmd *tv_cmd = container_of(se_cmd,
 322                                 struct tcm_vhost_cmd, tvc_se_cmd);
 323         vhost_scsi_complete_cmd(tv_cmd);
 324         return 0;
 325 }
 326
 327 static int tcm_vhost_queue_tm_rsp(struct se_cmd *se_cmd)
 328 {
 329         return 0;
 330 }
 331
 332 static void vhost_scsi_free_cmd(struct tcm_vhost_cmd *tv_cmd)
 333 {
 334         struct se_cmd *se_cmd = &tv_cmd->tvc_se_cmd;
 335
 336         /* TODO locking against target/backend threads? */
 337         transport_generic_free_cmd(se_cmd, 1);
 338
 339         if (tv_cmd->tvc_sgl_count) {
 340                 u32 i;
 341                 for (i = 0; i < tv_cmd->tvc_sgl_count; i++)
 342                         put_page(sg_page(&tv_cmd->tvc_sgl[i]));
 343
 344                 kfree(tv_cmd->tvc_sgl);
 345         }
 346
 347         kfree(tv_cmd);
 348 }
 349
 350 /* Dequeue a command from the completion list */
 351 static struct tcm_vhost_cmd *vhost_scsi_get_cmd_from_completion(
 352         struct vhost_scsi *vs)
 353 {
 354         struct tcm_vhost_cmd *tv_cmd = NULL;
 355
 356         spin_lock_bh(&vs->vs_completion_lock);
 357         if (list_empty(&vs->vs_completion_list)) {
 358                 spin_unlock_bh(&vs->vs_completion_lock);
 359                 return NULL;
 360         }
 361
 362         list_for_each_entry(tv_cmd, &vs->vs_completion_list,
 363                             tvc_completion_list) {
 364                 list_del(&tv_cmd->tvc_completion_list);
 365                 break;
 366         }
 367         spin_unlock_bh(&vs->vs_completion_lock);
 368         return tv_cmd;
 369 }
 370
 371 /* Fill in status and signal that we are done processing this command
 372  *
 373  * This is scheduled in the vhost work queue so we are called with the owner
 374  * process mm and can access the vring.
 375  */
 376 static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
 377 {
 378         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 379                                         vs_completion_work);
 380         struct tcm_vhost_cmd *tv_cmd;
 381
 382         while ((tv_cmd = vhost_scsi_get_cmd_from_completion(vs))) {
 383                 struct virtio_scsi_cmd_resp v_rsp;
 384                 struct se_cmd *se_cmd = &tv_cmd->tvc_se_cmd;
 385                 int ret;
 386
 387                 pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__,
 388                         tv_cmd, se_cmd->residual_count, se_cmd->scsi_status);
 389
 390                 memset(&v_rsp, 0, sizeof(v_rsp));
 391                 v_rsp.resid = se_cmd->residual_count;
 392                 /* TODO is status_qualifier field needed? */
 393                 v_rsp.status = se_cmd->scsi_status;
 394                 v_rsp.sense_len = se_cmd->scsi_sense_length;
 395                 memcpy(v_rsp.sense, tv_cmd->tvc_sense_buf,
 396                        v_rsp.sense_len);
 397                 ret = copy_to_user(tv_cmd->tvc_resp, &v_rsp, sizeof(v_rsp));
 398                 if (likely(ret == 0))
 399                         vhost_add_used(&vs->vqs[2], tv_cmd->tvc_vq_desc, 0);
 400                 else
 401                         pr_err("Faulted on virtio_scsi_cmd_resp\n");
 402
 403                 vhost_scsi_free_cmd(tv_cmd);
 404         }
 405
 406         vhost_signal(&vs->dev, &vs->vqs[2]);
 407 }
 408
 409 static struct tcm_vhost_cmd *vhost_scsi_allocate_cmd(
 410         struct tcm_vhost_tpg *tv_tpg,
 411         struct virtio_scsi_cmd_req *v_req,
 412         u32 exp_data_len,
 413         int data_direction)
 414 {
 415         struct tcm_vhost_cmd *tv_cmd;
 416         struct tcm_vhost_nexus *tv_nexus;
 417
 418         tv_nexus = tv_tpg->tpg_nexus;
 419         if (!tv_nexus) {
 420                 pr_err("Unable to locate active struct tcm_vhost_nexus\n");
 421                 return ERR_PTR(-EIO);
 422         }
 423
 424         tv_cmd = kzalloc(sizeof(struct tcm_vhost_cmd), GFP_ATOMIC);
 425         if (!tv_cmd) {
 426                 pr_err("Unable to allocate struct tcm_vhost_cmd\n");
 427                 return ERR_PTR(-ENOMEM);
 428         }
 429         INIT_LIST_HEAD(&tv_cmd->tvc_completion_list);
 430         tv_cmd->tvc_tag = v_req->tag;
 431         tv_cmd->tvc_task_attr = v_req->task_attr;
 432         tv_cmd->tvc_exp_data_len = exp_data_len;
 433         tv_cmd->tvc_data_direction = data_direction;
 434         tv_cmd->tvc_nexus = tv_nexus;
 435
 436         return tv_cmd;
 437 }
 438
 439 /*
 440  * Map a user memory range into a scatterlist
 441  *
 442  * Returns the number of scatterlist entries used or -errno on error.
 443  */
 444 static int vhost_scsi_map_to_sgl(struct scatterlist *sgl,
 445         unsigned int sgl_count, void __user *ptr, size_t len, int write)
 446 {
 447         struct scatterlist *sg = sgl;
 448         unsigned int npages = 0;
 449         int ret;
 450
 451         while (len > 0) {
 452                 struct page *page;
 453                 unsigned int offset = (uintptr_t)ptr & ~PAGE_MASK;
 454                 unsigned int nbytes = min_t(unsigned int,
 455                                 PAGE_SIZE - offset, len);
 456
 457                 if (npages == sgl_count) {
 458                         ret = -ENOBUFS;
 459                         goto err;
 460                 }
 461
 462                 ret = get_user_pages_fast((unsigned long)ptr, 1, write, &page);
 463                 BUG_ON(ret == 0); /* we should either get our page or fail */
 464                 if (ret < 0)
 465                         goto err;
 466
 467                 sg_set_page(sg, page, nbytes, offset);
 468                 ptr += nbytes;
 469                 len -= nbytes;
 470                 sg++;
 471                 npages++;
 472         }
 473         return npages;
 474
 475 err:
 476         /* Put pages that we hold */
 477         for (sg = sgl; sg != &sgl[npages]; sg++)
 478                 put_page(sg_page(sg));
 479         return ret;
 480 }
 481
 482 static int vhost_scsi_map_iov_to_sgl(struct tcm_vhost_cmd *tv_cmd,
 483         struct iovec *iov, unsigned int niov, int write)
 484 {
 485         int ret;
 486         unsigned int i;
 487         u32 sgl_count;
 488         struct scatterlist *sg;
 489
 490         /*
 491          * Find out how long sglist needs to be
 492          */
 493         sgl_count = 0;
 494         for (i = 0; i < niov; i++) {
 495                 sgl_count += (((uintptr_t)iov[i].iov_base + iov[i].iov_len +
 496                                 PAGE_SIZE - 1) >> PAGE_SHIFT) -
 497                                 ((uintptr_t)iov[i].iov_base >> PAGE_SHIFT);
 498         }
 499         /* TODO overflow checking */
 500
 501         sg = kmalloc(sizeof(tv_cmd->tvc_sgl[0]) * sgl_count, GFP_ATOMIC);
 502         if (!sg)
 503                 return -ENOMEM;
 504         pr_debug("%s sg %p sgl_count %u is_err %d\n", __func__,
 505                sg, sgl_count, !sg);
 506         sg_init_table(sg, sgl_count);
 507
 508         tv_cmd->tvc_sgl = sg;
 509         tv_cmd->tvc_sgl_count = sgl_count;
 510
 511         pr_debug("Mapping %u iovecs for %u pages\n", niov, sgl_count);
 512         for (i = 0; i < niov; i++) {
 513                 ret = vhost_scsi_map_to_sgl(sg, sgl_count, iov[i].iov_base,
 514                                         iov[i].iov_len, write);
 515                 if (ret < 0) {
 516                         for (i = 0; i < tv_cmd->tvc_sgl_count; i++)
 517                                 put_page(sg_page(&tv_cmd->tvc_sgl[i]));
 518                         kfree(tv_cmd->tvc_sgl);
 519                         tv_cmd->tvc_sgl = NULL;
 520                         tv_cmd->tvc_sgl_count = 0;
 521                         return ret;
 522                 }
 523
 524                 sg += ret;
 525                 sgl_count -= ret;
 526         }
 527         return 0;
 528 }
 529
 530 static void tcm_vhost_submission_work(struct work_struct *work)
 531 {
 532         struct tcm_vhost_cmd *tv_cmd =
 533                 container_of(work, struct tcm_vhost_cmd, work);
 534         struct tcm_vhost_nexus *tv_nexus;
 535         struct se_cmd *se_cmd = &tv_cmd->tvc_se_cmd;
 536         struct scatterlist *sg_ptr, *sg_bidi_ptr = NULL;
 537         int rc, sg_no_bidi = 0;
 538
 539         if (tv_cmd->tvc_sgl_count) {
 540                 sg_ptr = tv_cmd->tvc_sgl;
 541                 /*
 542                  * For BIDI commands, pass in the extra READ buffer
 543                  * to transport_generic_map_mem_to_cmd() below..
 544                  */
 545 /* FIXME: Fix BIDI operation in tcm_vhost_submission_work() */
 546 #if 0
 547                 if (se_cmd->se_cmd_flags & SCF_BIDI) {
 548                         sg_bidi_ptr = NULL;
 549                         sg_no_bidi = 0;
 550                 }
 551 #endif
 552         } else {
 553                 sg_ptr = NULL;
 554         }
 555         tv_nexus = tv_cmd->tvc_nexus;
 556
 557         rc = target_submit_cmd_map_sgls(se_cmd, tv_nexus->tvn_se_sess,
 558                         tv_cmd->tvc_cdb, &tv_cmd->tvc_sense_buf[0],
 559                         tv_cmd->tvc_lun, tv_cmd->tvc_exp_data_len,
 560                         tv_cmd->tvc_task_attr, tv_cmd->tvc_data_direction,
 561                         0, sg_ptr, tv_cmd->tvc_sgl_count,
 562                         sg_bidi_ptr, sg_no_bidi);
 563         if (rc < 0) {
 564                 transport_send_check_condition_and_sense(se_cmd,
 565                                 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
 566                 transport_generic_free_cmd(se_cmd, 0);
 567         }
 568 }
 569
 570 static void vhost_scsi_handle_vq(struct vhost_scsi *vs)
 571 {
 572         struct vhost_virtqueue *vq = &vs->vqs[2];
 573         struct virtio_scsi_cmd_req v_req;
 574         struct tcm_vhost_tpg *tv_tpg;
 575         struct tcm_vhost_cmd *tv_cmd;
 576         u32 exp_data_len, data_first, data_num, data_direction;
 577         unsigned out, in, i;
 578         int head, ret;
 579
 580         /* Must use ioctl VHOST_SCSI_SET_ENDPOINT */
 581         tv_tpg = vs->vs_tpg;
 582         if (unlikely(!tv_tpg)) {
 583                 pr_err("%s endpoint not set\n", __func__);
 584                 return;
 585         }
 586
 587         mutex_lock(&vq->mutex);
 588         vhost_disable_notify(&vs->dev, vq);
 589
 590         for (;;) {
 591                 head = vhost_get_vq_desc(&vs->dev, vq, vq->iov,
 592                                         ARRAY_SIZE(vq->iov), &out, &in,
 593                                         NULL, NULL);
 594                 pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n",
 595                                         head, out, in);
 596                 /* On error, stop handling until the next kick. */
 597                 if (unlikely(head < 0))
 598                         break;
 599                 /* Nothing new?  Wait for eventfd to tell us they refilled. */
 600                 if (head == vq->num) {
 601                         if (unlikely(vhost_enable_notify(&vs->dev, vq))) {
 602                                 vhost_disable_notify(&vs->dev, vq);
 603                                 continue;
 604                         }
 605                         break;
 606                 }
 607
 608 /* FIXME: BIDI operation */
 609                 if (out == 1 && in == 1) {
 610                         data_direction = DMA_NONE;
 611                         data_first = 0;
 612                         data_num = 0;
 613                 } else if (out == 1 && in > 1) {
 614                         data_direction = DMA_FROM_DEVICE;
 615                         data_first = out + 1;
 616                         data_num = in - 1;
 617                 } else if (out > 1 && in == 1) {
 618                         data_direction = DMA_TO_DEVICE;
 619                         data_first = 1;
 620                         data_num = out - 1;
 621                 } else {
 622                         vq_err(vq, "Invalid buffer layout out: %u in: %u\n",
 623                                         out, in);
 624                         break;
 625                 }
 626
 627                 /*
 628                  * Check for a sane resp buffer so we can report errors to
 629                  * the guest.
 630                  */
 631                 if (unlikely(vq->iov[out].iov_len !=
 632                                         sizeof(struct virtio_scsi_cmd_resp))) {
 633                         vq_err(vq, "Expecting virtio_scsi_cmd_resp, got %zu"
 634                                 " bytes\n", vq->iov[out].iov_len);
 635                         break;
 636                 }
 637
 638                 if (unlikely(vq->iov[0].iov_len != sizeof(v_req))) {
 639                         vq_err(vq, "Expecting virtio_scsi_cmd_req, got %zu"
 640                                 " bytes\n", vq->iov[0].iov_len);
 641                         break;
 642                 }
 643                 pr_debug("Calling __copy_from_user: vq->iov[0].iov_base: %p,"
 644                         " len: %zu\n", vq->iov[0].iov_base, sizeof(v_req));
 645                 ret = __copy_from_user(&v_req, vq->iov[0].iov_base,
 646                                 sizeof(v_req));
 647                 if (unlikely(ret)) {
 648                         vq_err(vq, "Faulted on virtio_scsi_cmd_req\n");
 649                         break;
 650                 }
 651
 652                 exp_data_len = 0;
 653                 for (i = 0; i < data_num; i++)
 654                         exp_data_len += vq->iov[data_first + i].iov_len;
 655
 656                 tv_cmd = vhost_scsi_allocate_cmd(tv_tpg, &v_req,
 657                                         exp_data_len, data_direction);
 658                 if (IS_ERR(tv_cmd)) {
 659                         vq_err(vq, "vhost_scsi_allocate_cmd failed %ld\n",
 660                                         PTR_ERR(tv_cmd));
 661                         break;
 662                 }
 663                 pr_debug("Allocated tv_cmd: %p exp_data_len: %d, data_direction"
 664                         ": %d\n", tv_cmd, exp_data_len, data_direction);
 665
 666                 tv_cmd->tvc_vhost = vs;
 667
 668                 if (unlikely(vq->iov[out].iov_len !=
 669                                 sizeof(struct virtio_scsi_cmd_resp))) {
 670                         vq_err(vq, "Expecting virtio_scsi_cmd_resp, got %zu"
 671                                 " bytes, out: %d, in: %d\n",
 672                                 vq->iov[out].iov_len, out, in);
 673                         break;
 674                 }
 675
 676                 tv_cmd->tvc_resp = vq->iov[out].iov_base;
 677
 678                 /*
 679                  * Copy in the recieved CDB descriptor into tv_cmd->tvc_cdb
 680                  * that will be used by tcm_vhost_new_cmd_map() and down into
 681                  * target_setup_cmd_from_cdb()
 682                  */
 683                 memcpy(tv_cmd->tvc_cdb, v_req.cdb, TCM_VHOST_MAX_CDB_SIZE);
 684                 /*
 685                  * Check that the recieved CDB size does not exceeded our
 686                  * hardcoded max for tcm_vhost
 687                  */
 688                 /* TODO what if cdb was too small for varlen cdb header? */
 689                 if (unlikely(scsi_command_size(tv_cmd->tvc_cdb) >
 690                                         TCM_VHOST_MAX_CDB_SIZE)) {
 691                         vq_err(vq, "Received SCSI CDB with command_size: %d that"
 692                                 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
 693                                 scsi_command_size(tv_cmd->tvc_cdb),
 694                                 TCM_VHOST_MAX_CDB_SIZE);
 695                         break; /* TODO */
 696                 }
 697                 tv_cmd->tvc_lun = ((v_req.lun[2] << 8) | v_req.lun[3]) & 0x3FFF;
 698
 699                 pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n",
 700                         tv_cmd->tvc_cdb[0], tv_cmd->tvc_lun);
 701
 702                 if (data_direction != DMA_NONE) {
 703                         ret = vhost_scsi_map_iov_to_sgl(tv_cmd,
 704                                         &vq->iov[data_first], data_num,
 705                                         data_direction == DMA_TO_DEVICE);
 706                         if (unlikely(ret)) {
 707                                 vq_err(vq, "Failed to map iov to sgl\n");
 708                                 break; /* TODO */
 709                         }
 710                 }
 711
 712                 /*
 713                  * Save the descriptor from vhost_get_vq_desc() to be used to
 714                  * complete the virtio-scsi request in TCM callback context via
 715                  * tcm_vhost_queue_data_in() and tcm_vhost_queue_status()
 716                  */
 717                 tv_cmd->tvc_vq_desc = head;
 718                 /*
 719                  * Dispatch tv_cmd descriptor for cmwq execution in process
 720                  * context provided by tcm_vhost_workqueue.  This also ensures
 721                  * tv_cmd is executed on the same kworker CPU as this vhost
 722                  * thread to gain positive L2 cache locality effects..
 723                  */
 724                 INIT_WORK(&tv_cmd->work, tcm_vhost_submission_work);
 725                 queue_work(tcm_vhost_workqueue, &tv_cmd->work);
 726         }
 727
 728         mutex_unlock(&vq->mutex);
 729 }
 730
 731 static void vhost_scsi_ctl_handle_kick(struct vhost_work *work)
 732 {
 733         pr_debug("%s: The handling func for control queue.\n", __func__);
 734 }
 735
 736 static void vhost_scsi_evt_handle_kick(struct vhost_work *work)
 737 {
 738         pr_debug("%s: The handling func for event queue.\n", __func__);
 739 }
 740
 741 static void vhost_scsi_handle_kick(struct vhost_work *work)
 742 {
 743         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
 744                                                 poll.work);
 745         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
 746
 747         vhost_scsi_handle_vq(vs);
 748 }
 749
 750 /*
 751  * Called from vhost_scsi_ioctl() context to walk the list of available
 752  * tcm_vhost_tpg with an active struct tcm_vhost_nexus
 753  */
 754 static int vhost_scsi_set_endpoint(
 755         struct vhost_scsi *vs,
 756         struct vhost_scsi_target *t)
 757 {
 758         struct tcm_vhost_tport *tv_tport;
 759         struct tcm_vhost_tpg *tv_tpg;
 760         int index;
 761
 762         mutex_lock(&vs->dev.mutex);
 763         /* Verify that ring has been setup correctly. */
 764         for (index = 0; index < vs->dev.nvqs; ++index) {
 765                 /* Verify that ring has been setup correctly. */
 766                 if (!vhost_vq_access_ok(&vs->vqs[index])) {
 767                         mutex_unlock(&vs->dev.mutex);
 768                         return -EFAULT;
 769                 }
 770         }
 771         mutex_unlock(&vs->dev.mutex);
 772
 773         mutex_lock(&tcm_vhost_mutex);
 774         list_for_each_entry(tv_tpg, &tcm_vhost_list, tv_tpg_list) {
 775                 mutex_lock(&tv_tpg->tv_tpg_mutex);
 776                 if (!tv_tpg->tpg_nexus) {
 777                         mutex_unlock(&tv_tpg->tv_tpg_mutex);
 778                         continue;
 779                 }
 780                 if (tv_tpg->tv_tpg_vhost_count != 0) {
 781                         mutex_unlock(&tv_tpg->tv_tpg_mutex);
 782                         continue;
 783                 }
 784                 tv_tport = tv_tpg->tport;
 785
 786                 if (!strcmp(tv_tport->tport_name, t->vhost_wwpn) &&
 787                     (tv_tpg->tport_tpgt == t->vhost_tpgt)) {
 788                         tv_tpg->tv_tpg_vhost_count++;
 789                         mutex_unlock(&tv_tpg->tv_tpg_mutex);
 790                         mutex_unlock(&tcm_vhost_mutex);
 791
 792                         mutex_lock(&vs->dev.mutex);
 793                         if (vs->vs_tpg) {
 794                                 mutex_unlock(&vs->dev.mutex);
 795                                 mutex_lock(&tv_tpg->tv_tpg_mutex);
 796                                 tv_tpg->tv_tpg_vhost_count--;
 797                                 mutex_unlock(&tv_tpg->tv_tpg_mutex);
 798                                 return -EEXIST;
 799                         }
 800
 801                         vs->vs_tpg = tv_tpg;
 802                         smp_mb__after_atomic_inc();
 803                         mutex_unlock(&vs->dev.mutex);
 804                         return 0;
 805                 }
 806                 mutex_unlock(&tv_tpg->tv_tpg_mutex);
 807         }
 808         mutex_unlock(&tcm_vhost_mutex);
 809         return -EINVAL;
 810 }
 811
 812 static int vhost_scsi_clear_endpoint(
 813         struct vhost_scsi *vs,
 814         struct vhost_scsi_target *t)
 815 {
 816         struct tcm_vhost_tport *tv_tport;
 817         struct tcm_vhost_tpg *tv_tpg;
 818         int index, ret;
 819
 820         mutex_lock(&vs->dev.mutex);
 821         /* Verify that ring has been setup correctly. */
 822         for (index = 0; index < vs->dev.nvqs; ++index) {
 823                 if (!vhost_vq_access_ok(&vs->vqs[index])) {
 824                         ret = -EFAULT;
 825                         goto err;
 826                 }
 827         }
 828
 829         if (!vs->vs_tpg) {
 830                 ret = -ENODEV;
 831                 goto err;
 832         }
 833         tv_tpg = vs->vs_tpg;
 834         tv_tport = tv_tpg->tport;
 835
 836         if (strcmp(tv_tport->tport_name, t->vhost_wwpn) ||
 837             (tv_tpg->tport_tpgt != t->vhost_tpgt)) {
 838                 pr_warn("tv_tport->tport_name: %s, tv_tpg->tport_tpgt: %hu"
 839                         " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
 840                         tv_tport->tport_name, tv_tpg->tport_tpgt,
 841                         t->vhost_wwpn, t->vhost_tpgt);
 842                 ret = -EINVAL;
 843                 goto err;
 844         }
 845         tv_tpg->tv_tpg_vhost_count--;
 846         vs->vs_tpg = NULL;
 847         mutex_unlock(&vs->dev.mutex);
 848
 849         return 0;
 850
 851 err:
 852         mutex_unlock(&vs->dev.mutex);
 853         return ret;
 854 }
 855
 856 static int vhost_scsi_open(struct inode *inode, struct file *f)
 857 {
 858         struct vhost_scsi *s;
 859         int r;
 860
 861         s = kzalloc(sizeof(*s), GFP_KERNEL);
 862         if (!s)
 863                 return -ENOMEM;
 864
 865         vhost_work_init(&s->vs_completion_work, vhost_scsi_complete_cmd_work);
 866         INIT_LIST_HEAD(&s->vs_completion_list);
 867         spin_lock_init(&s->vs_completion_lock);
 868
 869         s->vqs[VHOST_SCSI_VQ_CTL].handle_kick = vhost_scsi_ctl_handle_kick;
 870         s->vqs[VHOST_SCSI_VQ_EVT].handle_kick = vhost_scsi_evt_handle_kick;
 871         s->vqs[VHOST_SCSI_VQ_IO].handle_kick = vhost_scsi_handle_kick;
 872         r = vhost_dev_init(&s->dev, s->vqs, 3);
 873         if (r < 0) {
 874                 kfree(s);
 875                 return r;
 876         }
 877
 878         f->private_data = s;
 879         return 0;
 880 }
 881
 882 static int vhost_scsi_release(struct inode *inode, struct file *f)
 883 {
 884         struct vhost_scsi *s = f->private_data;
 885
 886         if (s->vs_tpg && s->vs_tpg->tport) {
 887                 struct vhost_scsi_target backend;
 888
 889                 memcpy(backend.vhost_wwpn, s->vs_tpg->tport->tport_name,
 890                                 sizeof(backend.vhost_wwpn));
 891                 backend.vhost_tpgt = s->vs_tpg->tport_tpgt;
 892                 vhost_scsi_clear_endpoint(s, &backend);
 893         }
 894
 895         vhost_dev_stop(&s->dev);
 896         vhost_dev_cleanup(&s->dev, false);
 897         kfree(s);
 898         return 0;
 899 }
 900
 901 static void vhost_scsi_flush_vq(struct vhost_scsi *vs, int index)
 902 {
 903         vhost_poll_flush(&vs->dev.vqs[index].poll);
 904 }
 905
 906 static void vhost_scsi_flush(struct vhost_scsi *vs)
 907 {
 908         vhost_scsi_flush_vq(vs, VHOST_SCSI_VQ_CTL);
 909         vhost_scsi_flush_vq(vs, VHOST_SCSI_VQ_EVT);
 910         vhost_scsi_flush_vq(vs, VHOST_SCSI_VQ_IO);
 911 }
 912
 913 static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features)
 914 {
 915         if (features & ~VHOST_FEATURES)
 916                 return -EOPNOTSUPP;
 917
 918         mutex_lock(&vs->dev.mutex);
 919         if ((features & (1 << VHOST_F_LOG_ALL)) &&
 920             !vhost_log_access_ok(&vs->dev)) {
 921                 mutex_unlock(&vs->dev.mutex);
 922                 return -EFAULT;
 923         }
 924         vs->dev.acked_features = features;
 925         smp_wmb();
 926         vhost_scsi_flush(vs);
 927         mutex_unlock(&vs->dev.mutex);
 928         return 0;
 929 }
 930
 931 static long vhost_scsi_ioctl(struct file *f, unsigned int ioctl,
 932                                 unsigned long arg)
 933 {
 934         struct vhost_scsi *vs = f->private_data;
 935         struct vhost_scsi_target backend;
 936         void __user *argp = (void __user *)arg;
 937         u64 __user *featurep = argp;
 938         u64 features;
 939         int r, abi_version = VHOST_SCSI_ABI_VERSION;
 940
 941         switch (ioctl) {
 942         case VHOST_SCSI_SET_ENDPOINT:
 943                 if (copy_from_user(&backend, argp, sizeof backend))
 944                         return -EFAULT;
 945                 if (backend.reserved != 0)
 946                         return -EOPNOTSUPP;
 947
 948                 return vhost_scsi_set_endpoint(vs, &backend);
 949         case VHOST_SCSI_CLEAR_ENDPOINT:
 950                 if (copy_from_user(&backend, argp, sizeof backend))
 951                         return -EFAULT;
 952                 if (backend.reserved != 0)
 953                         return -EOPNOTSUPP;
 954
 955                 return vhost_scsi_clear_endpoint(vs, &backend);
 956         case VHOST_SCSI_GET_ABI_VERSION:
 957                 if (copy_to_user(argp, &abi_version, sizeof abi_version))
 958                         return -EFAULT;
 959                 return 0;
 960         case VHOST_GET_FEATURES:
 961                 features = VHOST_FEATURES;
 962                 if (copy_to_user(featurep, &features, sizeof features))
 963                         return -EFAULT;
 964                 return 0;
 965         case VHOST_SET_FEATURES:
 966                 if (copy_from_user(&features, featurep, sizeof features))
 967                         return -EFAULT;
 968                 return vhost_scsi_set_features(vs, features);
 969         default:
 970                 mutex_lock(&vs->dev.mutex);
 971                 r = vhost_dev_ioctl(&vs->dev, ioctl, argp);
 972                 /* TODO: flush backend after dev ioctl. */
 973                 if (r == -ENOIOCTLCMD)
 974                         r = vhost_vring_ioctl(&vs->dev, ioctl, argp);
 975                 mutex_unlock(&vs->dev.mutex);
 976                 return r;
 977         }
 978 }
 979
 980 #ifdef CONFIG_COMPAT
 981 static long vhost_scsi_compat_ioctl(struct file *f, unsigned int ioctl,
 982                                 unsigned long arg)
 983 {
 984         return vhost_scsi_ioctl(f, ioctl, (unsigned long)compat_ptr(arg));
 985 }
 986 #endif
 987
 988 static const struct file_operations vhost_scsi_fops = {
 989         .owner          = THIS_MODULE,
 990         .release        = vhost_scsi_release,
 991         .unlocked_ioctl = vhost_scsi_ioctl,
 992 #ifdef CONFIG_COMPAT
 993         .compat_ioctl   = vhost_scsi_compat_ioctl,
 994 #endif
 995         .open           = vhost_scsi_open,
 996         .llseek         = noop_llseek,
 997 };
 998
 999 static struct miscdevice vhost_scsi_misc = {
1000         MISC_DYNAMIC_MINOR,
1001         "vhost-scsi",
1002         &vhost_scsi_fops,
1003 };
1004
1005 static int __init vhost_scsi_register(void)
1006 {
1007         return misc_register(&vhost_scsi_misc);
1008 }
1009
1010 static int vhost_scsi_deregister(void)
1011 {
1012         return misc_deregister(&vhost_scsi_misc);
1013 }
1014
1015 static char *tcm_vhost_dump_proto_id(struct tcm_vhost_tport *tport)
1016 {
1017         switch (tport->tport_proto_id) {
1018         case SCSI_PROTOCOL_SAS:
1019                 return "SAS";
1020         case SCSI_PROTOCOL_FCP:
1021                 return "FCP";
1022         case SCSI_PROTOCOL_ISCSI:
1023                 return "iSCSI";
1024         default:
1025                 break;
1026         }
1027
1028         return "Unknown";
1029 }
1030
1031 static int tcm_vhost_port_link(struct se_portal_group *se_tpg,
1032         struct se_lun *lun)
1033 {
1034         struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg,
1035                                 struct tcm_vhost_tpg, se_tpg);
1036
1037         mutex_lock(&tv_tpg->tv_tpg_mutex);
1038         tv_tpg->tv_tpg_port_count++;
1039         mutex_unlock(&tv_tpg->tv_tpg_mutex);
1040
1041         return 0;
1042 }
1043
1044 static void tcm_vhost_port_unlink(struct se_portal_group *se_tpg,
1045         struct se_lun *se_lun)
1046 {
1047         struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg,
1048                                 struct tcm_vhost_tpg, se_tpg);
1049
1050         mutex_lock(&tv_tpg->tv_tpg_mutex);
1051         tv_tpg->tv_tpg_port_count--;
1052         mutex_unlock(&tv_tpg->tv_tpg_mutex);
1053 }
1054
1055 static struct se_node_acl *tcm_vhost_make_nodeacl(
1056         struct se_portal_group *se_tpg,
1057         struct config_group *group,
1058         const char *name)
1059 {
1060         struct se_node_acl *se_nacl, *se_nacl_new;
1061         struct tcm_vhost_nacl *nacl;
1062         u64 wwpn = 0;
1063         u32 nexus_depth;
1064
1065         /* tcm_vhost_parse_wwn(name, &wwpn, 1) < 0)
1066                 return ERR_PTR(-EINVAL); */
1067         se_nacl_new = tcm_vhost_alloc_fabric_acl(se_tpg);
1068         if (!se_nacl_new)
1069                 return ERR_PTR(-ENOMEM);
1070
1071         nexus_depth = 1;
1072         /*
1073          * se_nacl_new may be released by core_tpg_add_initiator_node_acl()
1074          * when converting a NodeACL from demo mode -> explict
1075          */
1076         se_nacl = core_tpg_add_initiator_node_acl(se_tpg, se_nacl_new,
1077                                 name, nexus_depth);
1078         if (IS_ERR(se_nacl)) {
1079                 tcm_vhost_release_fabric_acl(se_tpg, se_nacl_new);
1080                 return se_nacl;
1081         }
1082         /*
1083          * Locate our struct tcm_vhost_nacl and set the FC Nport WWPN
1084          */
1085         nacl = container_of(se_nacl, struct tcm_vhost_nacl, se_node_acl);
1086         nacl->iport_wwpn = wwpn;
1087
1088         return se_nacl;
1089 }
1090
1091 static void tcm_vhost_drop_nodeacl(struct se_node_acl *se_acl)
1092 {
1093         struct tcm_vhost_nacl *nacl = container_of(se_acl,
1094                                 struct tcm_vhost_nacl, se_node_acl);
1095         core_tpg_del_initiator_node_acl(se_acl->se_tpg, se_acl, 1);
1096         kfree(nacl);
1097 }
1098
1099 static int tcm_vhost_make_nexus(struct tcm_vhost_tpg *tv_tpg,
1100         const char *name)
1101 {
1102         struct se_portal_group *se_tpg;
1103         struct tcm_vhost_nexus *tv_nexus;
1104
1105         mutex_lock(&tv_tpg->tv_tpg_mutex);
1106         if (tv_tpg->tpg_nexus) {
1107                 mutex_unlock(&tv_tpg->tv_tpg_mutex);
1108                 pr_debug("tv_tpg->tpg_nexus already exists\n");
1109                 return -EEXIST;
1110         }
1111         se_tpg = &tv_tpg->se_tpg;
1112
1113         tv_nexus = kzalloc(sizeof(struct tcm_vhost_nexus), GFP_KERNEL);
1114         if (!tv_nexus) {
1115                 mutex_unlock(&tv_tpg->tv_tpg_mutex);
1116                 pr_err("Unable to allocate struct tcm_vhost_nexus\n");
1117                 return -ENOMEM;
1118         }
1119         /*
1120          *  Initialize the struct se_session pointer
1121          */
1122         tv_nexus->tvn_se_sess = transport_init_session();
1123         if (IS_ERR(tv_nexus->tvn_se_sess)) {
1124                 mutex_unlock(&tv_tpg->tv_tpg_mutex);
1125                 kfree(tv_nexus);
1126                 return -ENOMEM;
1127         }
1128         /*
1129          * Since we are running in 'demo mode' this call with generate a
1130          * struct se_node_acl for the tcm_vhost struct se_portal_group with
1131          * the SCSI Initiator port name of the passed configfs group 'name'.
1132          */
1133         tv_nexus->tvn_se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
1134                                 se_tpg, (unsigned char *)name);
1135         if (!tv_nexus->tvn_se_sess->se_node_acl) {
1136                 mutex_unlock(&tv_tpg->tv_tpg_mutex);
1137                 pr_debug("core_tpg_check_initiator_node_acl() failed"
1138                                 " for %s\n", name);
1139                 transport_free_session(tv_nexus->tvn_se_sess);
1140                 kfree(tv_nexus);
1141                 return -ENOMEM;
1142         }
1143         /*
1144          * Now register the TCM vhost virtual I_T Nexus as active with the
1145          * call to __transport_register_session()
1146          */
1147         __transport_register_session(se_tpg, tv_nexus->tvn_se_sess->se_node_acl,
1148                         tv_nexus->tvn_se_sess, tv_nexus);
1149         tv_tpg->tpg_nexus = tv_nexus;
1150
1151         mutex_unlock(&tv_tpg->tv_tpg_mutex);
1152         return 0;
1153 }
1154
1155 static int tcm_vhost_drop_nexus(struct tcm_vhost_tpg *tpg)
1156 {
1157         struct se_session *se_sess;
1158         struct tcm_vhost_nexus *tv_nexus;
1159
1160         mutex_lock(&tpg->tv_tpg_mutex);
1161         tv_nexus = tpg->tpg_nexus;
1162         if (!tv_nexus) {
1163                 mutex_unlock(&tpg->tv_tpg_mutex);
1164                 return -ENODEV;
1165         }
1166
1167         se_sess = tv_nexus->tvn_se_sess;
1168         if (!se_sess) {
1169                 mutex_unlock(&tpg->tv_tpg_mutex);
1170                 return -ENODEV;
1171         }
1172
1173         if (tpg->tv_tpg_port_count != 0) {
1174                 mutex_unlock(&tpg->tv_tpg_mutex);
1175                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
1176                         " active TPG port count: %d\n",
1177                         tpg->tv_tpg_port_count);
1178                 return -EBUSY;
1179         }
1180
1181         if (tpg->tv_tpg_vhost_count != 0) {
1182                 mutex_unlock(&tpg->tv_tpg_mutex);
1183                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
1184                         " active TPG vhost count: %d\n",
1185                         tpg->tv_tpg_vhost_count);
1186                 return -EBUSY;
1187         }
1188
1189         pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated"
1190                 " %s Initiator Port: %s\n", tcm_vhost_dump_proto_id(tpg->tport),
1191                 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1192         /*
1193          * Release the SCSI I_T Nexus to the emulated vhost Target Port
1194          */
1195         transport_deregister_session(tv_nexus->tvn_se_sess);
1196         tpg->tpg_nexus = NULL;
1197         mutex_unlock(&tpg->tv_tpg_mutex);
1198
1199         kfree(tv_nexus);
1200         return 0;
1201 }
1202
1203 static ssize_t tcm_vhost_tpg_show_nexus(struct se_portal_group *se_tpg,
1204         char *page)
1205 {
1206         struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg,
1207                                 struct tcm_vhost_tpg, se_tpg);
1208         struct tcm_vhost_nexus *tv_nexus;
1209         ssize_t ret;
1210
1211         mutex_lock(&tv_tpg->tv_tpg_mutex);
1212         tv_nexus = tv_tpg->tpg_nexus;
1213         if (!tv_nexus) {
1214                 mutex_unlock(&tv_tpg->tv_tpg_mutex);
1215                 return -ENODEV;
1216         }
1217         ret = snprintf(page, PAGE_SIZE, "%s\n",
1218                         tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1219         mutex_unlock(&tv_tpg->tv_tpg_mutex);
1220
1221         return ret;
1222 }
1223
1224 static ssize_t tcm_vhost_tpg_store_nexus(struct se_portal_group *se_tpg,
1225         const char *page,
1226         size_t count)
1227 {
1228         struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg,
1229                                 struct tcm_vhost_tpg, se_tpg);
1230         struct tcm_vhost_tport *tport_wwn = tv_tpg->tport;
1231         unsigned char i_port[TCM_VHOST_NAMELEN], *ptr, *port_ptr;
1232         int ret;
1233         /*
1234          * Shutdown the active I_T nexus if 'NULL' is passed..
1235          */
1236         if (!strncmp(page, "NULL", 4)) {
1237                 ret = tcm_vhost_drop_nexus(tv_tpg);
1238                 return (!ret) ? count : ret;
1239         }
1240         /*
1241          * Otherwise make sure the passed virtual Initiator port WWN matches
1242          * the fabric protocol_id set in tcm_vhost_make_tport(), and call
1243          * tcm_vhost_make_nexus().
1244          */
1245         if (strlen(page) >= TCM_VHOST_NAMELEN) {
1246                 pr_err("Emulated NAA Sas Address: %s, exceeds"
1247                                 " max: %d\n", page, TCM_VHOST_NAMELEN);
1248                 return -EINVAL;
1249         }
1250         snprintf(&i_port[0], TCM_VHOST_NAMELEN, "%s", page);
1251
1252         ptr = strstr(i_port, "naa.");
1253         if (ptr) {
1254                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
1255                         pr_err("Passed SAS Initiator Port %s does not"
1256                                 " match target port protoid: %s\n", i_port,
1257                                 tcm_vhost_dump_proto_id(tport_wwn));
1258                         return -EINVAL;
1259                 }
1260                 port_ptr = &i_port[0];
1261                 goto check_newline;
1262         }
1263         ptr = strstr(i_port, "fc.");
1264         if (ptr) {
1265                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
1266                         pr_err("Passed FCP Initiator Port %s does not"
1267                                 " match target port protoid: %s\n", i_port,
1268                                 tcm_vhost_dump_proto_id(tport_wwn));
1269                         return -EINVAL;
1270                 }
1271                 port_ptr = &i_port[3]; /* Skip over "fc." */
1272                 goto check_newline;
1273         }
1274         ptr = strstr(i_port, "iqn.");
1275         if (ptr) {
1276                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
1277                         pr_err("Passed iSCSI Initiator Port %s does not"
1278                                 " match target port protoid: %s\n", i_port,
1279                                 tcm_vhost_dump_proto_id(tport_wwn));
1280                         return -EINVAL;
1281                 }
1282                 port_ptr = &i_port[0];
1283                 goto check_newline;
1284         }
1285         pr_err("Unable to locate prefix for emulated Initiator Port:"
1286                         " %s\n", i_port);
1287         return -EINVAL;
1288         /*
1289          * Clear any trailing newline for the NAA WWN
1290          */
1291 check_newline:
1292         if (i_port[strlen(i_port)-1] == '\n')
1293                 i_port[strlen(i_port)-1] = '\0';
1294
1295         ret = tcm_vhost_make_nexus(tv_tpg, port_ptr);
1296         if (ret < 0)
1297                 return ret;
1298
1299         return count;
1300 }
1301
1302 TF_TPG_BASE_ATTR(tcm_vhost, nexus, S_IRUGO | S_IWUSR);
1303
1304 static struct configfs_attribute *tcm_vhost_tpg_attrs[] = {
1305         &tcm_vhost_tpg_nexus.attr,
1306         NULL,
1307 };
1308
1309 static struct se_portal_group *tcm_vhost_make_tpg(struct se_wwn *wwn,
1310         struct config_group *group,
1311         const char *name)
1312 {
1313         struct tcm_vhost_tport *tport = container_of(wwn,
1314                         struct tcm_vhost_tport, tport_wwn);
1315
1316         struct tcm_vhost_tpg *tpg;
1317         unsigned long tpgt;
1318         int ret;
1319
1320         if (strstr(name, "tpgt_") != name)
1321                 return ERR_PTR(-EINVAL);
1322         if (kstrtoul(name + 5, 10, &tpgt) || tpgt > UINT_MAX)
1323                 return ERR_PTR(-EINVAL);
1324
1325         tpg = kzalloc(sizeof(struct tcm_vhost_tpg), GFP_KERNEL);
1326         if (!tpg) {
1327                 pr_err("Unable to allocate struct tcm_vhost_tpg");
1328                 return ERR_PTR(-ENOMEM);
1329         }
1330         mutex_init(&tpg->tv_tpg_mutex);
1331         INIT_LIST_HEAD(&tpg->tv_tpg_list);
1332         tpg->tport = tport;
1333         tpg->tport_tpgt = tpgt;
1334
1335         ret = core_tpg_register(&tcm_vhost_fabric_configfs->tf_ops, wwn,
1336                                 &tpg->se_tpg, tpg, TRANSPORT_TPG_TYPE_NORMAL);
1337         if (ret < 0) {
1338                 kfree(tpg);
1339                 return NULL;
1340         }
1341         mutex_lock(&tcm_vhost_mutex);
1342         list_add_tail(&tpg->tv_tpg_list, &tcm_vhost_list);
1343         mutex_unlock(&tcm_vhost_mutex);
1344
1345         return &tpg->se_tpg;
1346 }
1347
1348 static void tcm_vhost_drop_tpg(struct se_portal_group *se_tpg)
1349 {
1350         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1351                                 struct tcm_vhost_tpg, se_tpg);
1352
1353         mutex_lock(&tcm_vhost_mutex);
1354         list_del(&tpg->tv_tpg_list);
1355         mutex_unlock(&tcm_vhost_mutex);
1356         /*
1357          * Release the virtual I_T Nexus for this vhost TPG
1358          */
1359         tcm_vhost_drop_nexus(tpg);
1360         /*
1361          * Deregister the se_tpg from TCM..
1362          */
1363         core_tpg_deregister(se_tpg);
1364         kfree(tpg);
1365 }
1366
1367 static struct se_wwn *tcm_vhost_make_tport(struct target_fabric_configfs *tf,
1368         struct config_group *group,
1369         const char *name)
1370 {
1371         struct tcm_vhost_tport *tport;
1372         char *ptr;
1373         u64 wwpn = 0;
1374         int off = 0;
1375
1376         /* if (tcm_vhost_parse_wwn(name, &wwpn, 1) < 0)
1377                 return ERR_PTR(-EINVAL); */
1378
1379         tport = kzalloc(sizeof(struct tcm_vhost_tport), GFP_KERNEL);
1380         if (!tport) {
1381                 pr_err("Unable to allocate struct tcm_vhost_tport");
1382                 return ERR_PTR(-ENOMEM);
1383         }
1384         tport->tport_wwpn = wwpn;
1385         /*
1386          * Determine the emulated Protocol Identifier and Target Port Name
1387          * based on the incoming configfs directory name.
1388          */
1389         ptr = strstr(name, "naa.");
1390         if (ptr) {
1391                 tport->tport_proto_id = SCSI_PROTOCOL_SAS;
1392                 goto check_len;
1393         }
1394         ptr = strstr(name, "fc.");
1395         if (ptr) {
1396                 tport->tport_proto_id = SCSI_PROTOCOL_FCP;
1397                 off = 3; /* Skip over "fc." */
1398                 goto check_len;
1399         }
1400         ptr = strstr(name, "iqn.");
1401         if (ptr) {
1402                 tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
1403                 goto check_len;
1404         }
1405
1406         pr_err("Unable to locate prefix for emulated Target Port:"
1407                         " %s\n", name);
1408         kfree(tport);
1409         return ERR_PTR(-EINVAL);
1410
1411 check_len:
1412         if (strlen(name) >= TCM_VHOST_NAMELEN) {
1413                 pr_err("Emulated %s Address: %s, exceeds"
1414                         " max: %d\n", name, tcm_vhost_dump_proto_id(tport),
1415                         TCM_VHOST_NAMELEN);
1416                 kfree(tport);
1417                 return ERR_PTR(-EINVAL);
1418         }
1419         snprintf(&tport->tport_name[0], TCM_VHOST_NAMELEN, "%s", &name[off]);
1420
1421         pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target"
1422                 " %s Address: %s\n", tcm_vhost_dump_proto_id(tport), name);
1423
1424         return &tport->tport_wwn;
1425 }
1426
1427 static void tcm_vhost_drop_tport(struct se_wwn *wwn)
1428 {
1429         struct tcm_vhost_tport *tport = container_of(wwn,
1430                                 struct tcm_vhost_tport, tport_wwn);
1431
1432         pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target"
1433                 " %s Address: %s\n", tcm_vhost_dump_proto_id(tport),
1434                 tport->tport_name);
1435
1436         kfree(tport);
1437 }
1438
1439 static ssize_t tcm_vhost_wwn_show_attr_version(
1440         struct target_fabric_configfs *tf,
1441         char *page)
1442 {
1443         return sprintf(page, "TCM_VHOST fabric module %s on %s/%s"
1444                 "on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname,
1445                 utsname()->machine);
1446 }
1447
1448 TF_WWN_ATTR_RO(tcm_vhost, version);
1449
1450 static struct configfs_attribute *tcm_vhost_wwn_attrs[] = {
1451         &tcm_vhost_wwn_version.attr,
1452         NULL,
1453 };
1454
1455 static struct target_core_fabric_ops tcm_vhost_ops = {
1456         .get_fabric_name                = tcm_vhost_get_fabric_name,
1457         .get_fabric_proto_ident         = tcm_vhost_get_fabric_proto_ident,
1458         .tpg_get_wwn                    = tcm_vhost_get_fabric_wwn,
1459         .tpg_get_tag                    = tcm_vhost_get_tag,
1460         .tpg_get_default_depth          = tcm_vhost_get_default_depth,
1461         .tpg_get_pr_transport_id        = tcm_vhost_get_pr_transport_id,
1462         .tpg_get_pr_transport_id_len    = tcm_vhost_get_pr_transport_id_len,
1463         .tpg_parse_pr_out_transport_id  = tcm_vhost_parse_pr_out_transport_id,
1464         .tpg_check_demo_mode            = tcm_vhost_check_true,
1465         .tpg_check_demo_mode_cache      = tcm_vhost_check_true,
1466         .tpg_check_demo_mode_write_protect = tcm_vhost_check_false,
1467         .tpg_check_prod_mode_write_protect = tcm_vhost_check_false,
1468         .tpg_alloc_fabric_acl           = tcm_vhost_alloc_fabric_acl,
1469         .tpg_release_fabric_acl         = tcm_vhost_release_fabric_acl,
1470         .tpg_get_inst_index             = tcm_vhost_tpg_get_inst_index,
1471         .release_cmd                    = tcm_vhost_release_cmd,
1472         .shutdown_session               = tcm_vhost_shutdown_session,
1473         .close_session                  = tcm_vhost_close_session,
1474         .sess_get_index                 = tcm_vhost_sess_get_index,
1475         .sess_get_initiator_sid         = NULL,
1476         .write_pending                  = tcm_vhost_write_pending,
1477         .write_pending_status           = tcm_vhost_write_pending_status,
1478         .set_default_node_attributes    = tcm_vhost_set_default_node_attrs,
1479         .get_task_tag                   = tcm_vhost_get_task_tag,
1480         .get_cmd_state                  = tcm_vhost_get_cmd_state,
1481         .queue_data_in                  = tcm_vhost_queue_data_in,
1482         .queue_status                   = tcm_vhost_queue_status,
1483         .queue_tm_rsp                   = tcm_vhost_queue_tm_rsp,
1484         /*
1485          * Setup callers for generic logic in target_core_fabric_configfs.c
1486          */
1487         .fabric_make_wwn                = tcm_vhost_make_tport,
1488         .fabric_drop_wwn                = tcm_vhost_drop_tport,
1489         .fabric_make_tpg                = tcm_vhost_make_tpg,
1490         .fabric_drop_tpg                = tcm_vhost_drop_tpg,
1491         .fabric_post_link               = tcm_vhost_port_link,
1492         .fabric_pre_unlink              = tcm_vhost_port_unlink,
1493         .fabric_make_np                 = NULL,
1494         .fabric_drop_np                 = NULL,
1495         .fabric_make_nodeacl            = tcm_vhost_make_nodeacl,
1496         .fabric_drop_nodeacl            = tcm_vhost_drop_nodeacl,
1497 };
1498
1499 static int tcm_vhost_register_configfs(void)
1500 {
1501         struct target_fabric_configfs *fabric;
1502         int ret;
1503
1504         pr_debug("TCM_VHOST fabric module %s on %s/%s"
1505                 " on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname,
1506                 utsname()->machine);
1507         /*
1508          * Register the top level struct config_item_type with TCM core
1509          */
1510         fabric = target_fabric_configfs_init(THIS_MODULE, "vhost");
1511         if (IS_ERR(fabric)) {
1512                 pr_err("target_fabric_configfs_init() failed\n");
1513                 return PTR_ERR(fabric);
1514         }
1515         /*
1516          * Setup fabric->tf_ops from our local tcm_vhost_ops
1517          */
1518         fabric->tf_ops = tcm_vhost_ops;
1519         /*
1520          * Setup default attribute lists for various fabric->tf_cit_tmpl
1521          */
1522         TF_CIT_TMPL(fabric)->tfc_wwn_cit.ct_attrs = tcm_vhost_wwn_attrs;
1523         TF_CIT_TMPL(fabric)->tfc_tpg_base_cit.ct_attrs = tcm_vhost_tpg_attrs;
1524         TF_CIT_TMPL(fabric)->tfc_tpg_attrib_cit.ct_attrs = NULL;
1525         TF_CIT_TMPL(fabric)->tfc_tpg_param_cit.ct_attrs = NULL;
1526         TF_CIT_TMPL(fabric)->tfc_tpg_np_base_cit.ct_attrs = NULL;
1527         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_base_cit.ct_attrs = NULL;
1528         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_attrib_cit.ct_attrs = NULL;
1529         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_auth_cit.ct_attrs = NULL;
1530         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_param_cit.ct_attrs = NULL;
1531         /*
1532          * Register the fabric for use within TCM
1533          */
1534         ret = target_fabric_configfs_register(fabric);
1535         if (ret < 0) {
1536                 pr_err("target_fabric_configfs_register() failed"
1537                                 " for TCM_VHOST\n");
1538                 return ret;
1539         }
1540         /*
1541          * Setup our local pointer to *fabric
1542          */
1543         tcm_vhost_fabric_configfs = fabric;
1544         pr_debug("TCM_VHOST[0] - Set fabric -> tcm_vhost_fabric_configfs\n");
1545         return 0;
1546 };
1547
1548 static void tcm_vhost_deregister_configfs(void)
1549 {
1550         if (!tcm_vhost_fabric_configfs)
1551                 return;
1552
1553         target_fabric_configfs_deregister(tcm_vhost_fabric_configfs);
1554         tcm_vhost_fabric_configfs = NULL;
1555         pr_debug("TCM_VHOST[0] - Cleared tcm_vhost_fabric_configfs\n");
1556 };
1557
1558 static int __init tcm_vhost_init(void)
1559 {
1560         int ret = -ENOMEM;
1561         /*
1562          * Use our own dedicated workqueue for submitting I/O into
1563          * target core to avoid contention within system_wq.
1564          */
1565         tcm_vhost_workqueue = alloc_workqueue("tcm_vhost", 0, 0);
1566         if (!tcm_vhost_workqueue)
1567                 goto out;
1568
1569         ret = vhost_scsi_register();
1570         if (ret < 0)
1571                 goto out_destroy_workqueue;
1572
1573         ret = tcm_vhost_register_configfs();
1574         if (ret < 0)
1575                 goto out_vhost_scsi_deregister;
1576
1577         return 0;
1578
1579 out_vhost_scsi_deregister:
1580         vhost_scsi_deregister();
1581 out_destroy_workqueue:
1582         destroy_workqueue(tcm_vhost_workqueue);
1583 out:
1584         return ret;
1585 };
1586
1587 static void tcm_vhost_exit(void)
1588 {
1589         tcm_vhost_deregister_configfs();
1590         vhost_scsi_deregister();
1591         destroy_workqueue(tcm_vhost_workqueue);
1592 };
1593
1594 MODULE_DESCRIPTION("TCM_VHOST series fabric driver");
1595 MODULE_LICENSE("GPL");
1596 module_init(tcm_vhost_init);
1597 module_exit(tcm_vhost_exit);