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 #include <linux/llist.h>
  51 #include <linux/bitmap.h>
  52
  53 #include "vhost.c"
  54 #include "vhost.h"
  55 #include "tcm_vhost.h"
  56
  57 enum {
  58         VHOST_SCSI_VQ_CTL = 0,
  59         VHOST_SCSI_VQ_EVT = 1,
  60         VHOST_SCSI_VQ_IO = 2,
  61 };
  62
  63 #define VHOST_SCSI_MAX_TARGET   256
  64 #define VHOST_SCSI_MAX_VQ       128
  65
  66 struct vhost_scsi {
  67         /* Protected by vhost_scsi->dev.mutex */
  68         struct tcm_vhost_tpg *vs_tpg[VHOST_SCSI_MAX_TARGET];
  69         char vs_vhost_wwpn[TRANSPORT_IQN_LEN];
  70         bool vs_endpoint;
  71
  72         struct vhost_dev dev;
  73         struct vhost_virtqueue vqs[VHOST_SCSI_MAX_VQ];
  74
  75         struct vhost_work vs_completion_work; /* cmd completion work item */
  76         struct llist_head vs_completion_list; /* cmd completion queue */
  77 };
  78
  79 /* Local pointer to allocated TCM configfs fabric module */
  80 static struct target_fabric_configfs *tcm_vhost_fabric_configfs;
  81
  82 static struct workqueue_struct *tcm_vhost_workqueue;
  83
  84 /* Global spinlock to protect tcm_vhost TPG list for vhost IOCTL access */
  85 static DEFINE_MUTEX(tcm_vhost_mutex);
  86 static LIST_HEAD(tcm_vhost_list);
  87
  88 static int iov_num_pages(struct iovec *iov)
  89 {
  90         return (PAGE_ALIGN((unsigned long)iov->iov_base + iov->iov_len) -
  91                ((unsigned long)iov->iov_base & PAGE_MASK)) >> PAGE_SHIFT;
  92 }
  93
  94 static int tcm_vhost_check_true(struct se_portal_group *se_tpg)
  95 {
  96         return 1;
  97 }
  98
  99 static int tcm_vhost_check_false(struct se_portal_group *se_tpg)
 100 {
 101         return 0;
 102 }
 103
 104 static char *tcm_vhost_get_fabric_name(void)
 105 {
 106         return "vhost";
 107 }
 108
 109 static u8 tcm_vhost_get_fabric_proto_ident(struct se_portal_group *se_tpg)
 110 {
 111         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 112                                 struct tcm_vhost_tpg, se_tpg);
 113         struct tcm_vhost_tport *tport = tpg->tport;
 114
 115         switch (tport->tport_proto_id) {
 116         case SCSI_PROTOCOL_SAS:
 117                 return sas_get_fabric_proto_ident(se_tpg);
 118         case SCSI_PROTOCOL_FCP:
 119                 return fc_get_fabric_proto_ident(se_tpg);
 120         case SCSI_PROTOCOL_ISCSI:
 121                 return iscsi_get_fabric_proto_ident(se_tpg);
 122         default:
 123                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 124                         " SAS emulation\n", tport->tport_proto_id);
 125                 break;
 126         }
 127
 128         return sas_get_fabric_proto_ident(se_tpg);
 129 }
 130
 131 static char *tcm_vhost_get_fabric_wwn(struct se_portal_group *se_tpg)
 132 {
 133         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 134                                 struct tcm_vhost_tpg, se_tpg);
 135         struct tcm_vhost_tport *tport = tpg->tport;
 136
 137         return &tport->tport_name[0];
 138 }
 139
 140 static u16 tcm_vhost_get_tag(struct se_portal_group *se_tpg)
 141 {
 142         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 143                                 struct tcm_vhost_tpg, se_tpg);
 144         return tpg->tport_tpgt;
 145 }
 146
 147 static u32 tcm_vhost_get_default_depth(struct se_portal_group *se_tpg)
 148 {
 149         return 1;
 150 }
 151
 152 static u32 tcm_vhost_get_pr_transport_id(struct se_portal_group *se_tpg,
 153         struct se_node_acl *se_nacl,
 154         struct t10_pr_registration *pr_reg,
 155         int *format_code,
 156         unsigned char *buf)
 157 {
 158         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 159                                 struct tcm_vhost_tpg, se_tpg);
 160         struct tcm_vhost_tport *tport = tpg->tport;
 161
 162         switch (tport->tport_proto_id) {
 163         case SCSI_PROTOCOL_SAS:
 164                 return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 165                                         format_code, buf);
 166         case SCSI_PROTOCOL_FCP:
 167                 return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 168                                         format_code, buf);
 169         case SCSI_PROTOCOL_ISCSI:
 170                 return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 171                                         format_code, buf);
 172         default:
 173                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 174                         " SAS emulation\n", tport->tport_proto_id);
 175                 break;
 176         }
 177
 178         return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 179                         format_code, buf);
 180 }
 181
 182 static u32 tcm_vhost_get_pr_transport_id_len(struct se_portal_group *se_tpg,
 183         struct se_node_acl *se_nacl,
 184         struct t10_pr_registration *pr_reg,
 185         int *format_code)
 186 {
 187         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 188                                 struct tcm_vhost_tpg, se_tpg);
 189         struct tcm_vhost_tport *tport = tpg->tport;
 190
 191         switch (tport->tport_proto_id) {
 192         case SCSI_PROTOCOL_SAS:
 193                 return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 194                                         format_code);
 195         case SCSI_PROTOCOL_FCP:
 196                 return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 197                                         format_code);
 198         case SCSI_PROTOCOL_ISCSI:
 199                 return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 200                                         format_code);
 201         default:
 202                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 203                         " SAS emulation\n", tport->tport_proto_id);
 204                 break;
 205         }
 206
 207         return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 208                         format_code);
 209 }
 210
 211 static char *tcm_vhost_parse_pr_out_transport_id(struct se_portal_group *se_tpg,
 212         const char *buf,
 213         u32 *out_tid_len,
 214         char **port_nexus_ptr)
 215 {
 216         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 217                                 struct tcm_vhost_tpg, se_tpg);
 218         struct tcm_vhost_tport *tport = tpg->tport;
 219
 220         switch (tport->tport_proto_id) {
 221         case SCSI_PROTOCOL_SAS:
 222                 return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 223                                         port_nexus_ptr);
 224         case SCSI_PROTOCOL_FCP:
 225                 return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 226                                         port_nexus_ptr);
 227         case SCSI_PROTOCOL_ISCSI:
 228                 return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 229                                         port_nexus_ptr);
 230         default:
 231                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 232                         " SAS emulation\n", tport->tport_proto_id);
 233                 break;
 234         }
 235
 236         return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 237                         port_nexus_ptr);
 238 }
 239
 240 static struct se_node_acl *tcm_vhost_alloc_fabric_acl(
 241         struct se_portal_group *se_tpg)
 242 {
 243         struct tcm_vhost_nacl *nacl;
 244
 245         nacl = kzalloc(sizeof(struct tcm_vhost_nacl), GFP_KERNEL);
 246         if (!nacl) {
 247                 pr_err("Unable to allocate struct tcm_vhost_nacl\n");
 248                 return NULL;
 249         }
 250
 251         return &nacl->se_node_acl;
 252 }
 253
 254 static void tcm_vhost_release_fabric_acl(struct se_portal_group *se_tpg,
 255         struct se_node_acl *se_nacl)
 256 {
 257         struct tcm_vhost_nacl *nacl = container_of(se_nacl,
 258                         struct tcm_vhost_nacl, se_node_acl);
 259         kfree(nacl);
 260 }
 261
 262 static u32 tcm_vhost_tpg_get_inst_index(struct se_portal_group *se_tpg)
 263 {
 264         return 1;
 265 }
 266
 267 static void tcm_vhost_release_cmd(struct se_cmd *se_cmd)
 268 {
 269         return;
 270 }
 271
 272 static int tcm_vhost_shutdown_session(struct se_session *se_sess)
 273 {
 274         return 0;
 275 }
 276
 277 static void tcm_vhost_close_session(struct se_session *se_sess)
 278 {
 279         return;
 280 }
 281
 282 static u32 tcm_vhost_sess_get_index(struct se_session *se_sess)
 283 {
 284         return 0;
 285 }
 286
 287 static int tcm_vhost_write_pending(struct se_cmd *se_cmd)
 288 {
 289         /* Go ahead and process the write immediately */
 290         target_execute_cmd(se_cmd);
 291         return 0;
 292 }
 293
 294 static int tcm_vhost_write_pending_status(struct se_cmd *se_cmd)
 295 {
 296         return 0;
 297 }
 298
 299 static void tcm_vhost_set_default_node_attrs(struct se_node_acl *nacl)
 300 {
 301         return;
 302 }
 303
 304 static u32 tcm_vhost_get_task_tag(struct se_cmd *se_cmd)
 305 {
 306         return 0;
 307 }
 308
 309 static int tcm_vhost_get_cmd_state(struct se_cmd *se_cmd)
 310 {
 311         return 0;
 312 }
 313
 314 static void vhost_scsi_complete_cmd(struct tcm_vhost_cmd *tv_cmd)
 315 {
 316         struct vhost_scsi *vs = tv_cmd->tvc_vhost;
 317
 318         llist_add(&tv_cmd->tvc_completion_list, &vs->vs_completion_list);
 319
 320         vhost_work_queue(&vs->dev, &vs->vs_completion_work);
 321 }
 322
 323 static int tcm_vhost_queue_data_in(struct se_cmd *se_cmd)
 324 {
 325         struct tcm_vhost_cmd *tv_cmd = container_of(se_cmd,
 326                                 struct tcm_vhost_cmd, tvc_se_cmd);
 327         vhost_scsi_complete_cmd(tv_cmd);
 328         return 0;
 329 }
 330
 331 static int tcm_vhost_queue_status(struct se_cmd *se_cmd)
 332 {
 333         struct tcm_vhost_cmd *tv_cmd = container_of(se_cmd,
 334                                 struct tcm_vhost_cmd, tvc_se_cmd);
 335         vhost_scsi_complete_cmd(tv_cmd);
 336         return 0;
 337 }
 338
 339 static int tcm_vhost_queue_tm_rsp(struct se_cmd *se_cmd)
 340 {
 341         return 0;
 342 }
 343
 344 static void vhost_scsi_free_cmd(struct tcm_vhost_cmd *tv_cmd)
 345 {
 346         struct se_cmd *se_cmd = &tv_cmd->tvc_se_cmd;
 347
 348         /* TODO locking against target/backend threads? */
 349         transport_generic_free_cmd(se_cmd, 1);
 350
 351         if (tv_cmd->tvc_sgl_count) {
 352                 u32 i;
 353                 for (i = 0; i < tv_cmd->tvc_sgl_count; i++)
 354                         put_page(sg_page(&tv_cmd->tvc_sgl[i]));
 355
 356                 kfree(tv_cmd->tvc_sgl);
 357         }
 358
 359         kfree(tv_cmd);
 360 }
 361
 362 /* Fill in status and signal that we are done processing this command
 363  *
 364  * This is scheduled in the vhost work queue so we are called with the owner
 365  * process mm and can access the vring.
 366  */
 367 static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
 368 {
 369         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 370                                         vs_completion_work);
 371         DECLARE_BITMAP(signal, VHOST_SCSI_MAX_VQ);
 372         struct virtio_scsi_cmd_resp v_rsp;
 373         struct tcm_vhost_cmd *tv_cmd;
 374         struct llist_node *llnode;
 375         struct se_cmd *se_cmd;
 376         int ret, vq;
 377
 378         bitmap_zero(signal, VHOST_SCSI_MAX_VQ);
 379         llnode = llist_del_all(&vs->vs_completion_list);
 380         while (llnode) {
 381                 tv_cmd = llist_entry(llnode, struct tcm_vhost_cmd,
 382                                      tvc_completion_list);
 383                 llnode = llist_next(llnode);
 384                 se_cmd = &tv_cmd->tvc_se_cmd;
 385
 386                 pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__,
 387                         tv_cmd, se_cmd->residual_count, se_cmd->scsi_status);
 388
 389                 memset(&v_rsp, 0, sizeof(v_rsp));
 390                 v_rsp.resid = se_cmd->residual_count;
 391                 /* TODO is status_qualifier field needed? */
 392                 v_rsp.status = se_cmd->scsi_status;
 393                 v_rsp.sense_len = se_cmd->scsi_sense_length;
 394                 memcpy(v_rsp.sense, tv_cmd->tvc_sense_buf,
 395                        v_rsp.sense_len);
 396                 ret = copy_to_user(tv_cmd->tvc_resp, &v_rsp, sizeof(v_rsp));
 397                 if (likely(ret == 0)) {
 398                         vhost_add_used(tv_cmd->tvc_vq, tv_cmd->tvc_vq_desc, 0);
 399                         vq = tv_cmd->tvc_vq - vs->vqs;
 400                         __set_bit(vq, signal);
 401                 } else
 402                         pr_err("Faulted on virtio_scsi_cmd_resp\n");
 403
 404                 vhost_scsi_free_cmd(tv_cmd);
 405         }
 406
 407         vq = -1;
 408         while ((vq = find_next_bit(signal, VHOST_SCSI_MAX_VQ, vq + 1))
 409                 < VHOST_SCSI_MAX_VQ)
 410                 vhost_signal(&vs->dev, &vs->vqs[vq]);
 411 }
 412
 413 static struct tcm_vhost_cmd *vhost_scsi_allocate_cmd(
 414         struct tcm_vhost_tpg *tv_tpg,
 415         struct virtio_scsi_cmd_req *v_req,
 416         u32 exp_data_len,
 417         int data_direction)
 418 {
 419         struct tcm_vhost_cmd *tv_cmd;
 420         struct tcm_vhost_nexus *tv_nexus;
 421
 422         tv_nexus = tv_tpg->tpg_nexus;
 423         if (!tv_nexus) {
 424                 pr_err("Unable to locate active struct tcm_vhost_nexus\n");
 425                 return ERR_PTR(-EIO);
 426         }
 427
 428         tv_cmd = kzalloc(sizeof(struct tcm_vhost_cmd), GFP_ATOMIC);
 429         if (!tv_cmd) {
 430                 pr_err("Unable to allocate struct tcm_vhost_cmd\n");
 431                 return ERR_PTR(-ENOMEM);
 432         }
 433         tv_cmd->tvc_tag = v_req->tag;
 434         tv_cmd->tvc_task_attr = v_req->task_attr;
 435         tv_cmd->tvc_exp_data_len = exp_data_len;
 436         tv_cmd->tvc_data_direction = data_direction;
 437         tv_cmd->tvc_nexus = tv_nexus;
 438
 439         return tv_cmd;
 440 }
 441
 442 /*
 443  * Map a user memory range into a scatterlist
 444  *
 445  * Returns the number of scatterlist entries used or -errno on error.
 446  */
 447 static int vhost_scsi_map_to_sgl(struct scatterlist *sgl,
 448         unsigned int sgl_count, struct iovec *iov, int write)
 449 {
 450         unsigned int npages = 0, pages_nr, offset, nbytes;
 451         struct scatterlist *sg = sgl;
 452         void __user *ptr = iov->iov_base;
 453         size_t len = iov->iov_len;
 454         struct page **pages;
 455         int ret, i;
 456
 457         pages_nr = iov_num_pages(iov);
 458         if (pages_nr > sgl_count)
 459                 return -ENOBUFS;
 460
 461         pages = kmalloc(pages_nr * sizeof(struct page *), GFP_KERNEL);
 462         if (!pages)
 463                 return -ENOMEM;
 464
 465         ret = get_user_pages_fast((unsigned long)ptr, pages_nr, write, pages);
 466         /* No pages were pinned */
 467         if (ret < 0)
 468                 goto out;
 469         /* Less pages pinned than wanted */
 470         if (ret != pages_nr) {
 471                 for (i = 0; i < ret; i++)
 472                         put_page(pages[i]);
 473                 ret = -EFAULT;
 474                 goto out;
 475         }
 476
 477         while (len > 0) {
 478                 offset = (uintptr_t)ptr & ~PAGE_MASK;
 479                 nbytes = min_t(unsigned int, PAGE_SIZE - offset, len);
 480                 sg_set_page(sg, pages[npages], nbytes, offset);
 481                 ptr += nbytes;
 482                 len -= nbytes;
 483                 sg++;
 484                 npages++;
 485         }
 486
 487 out:
 488         kfree(pages);
 489         return ret;
 490 }
 491
 492 static int vhost_scsi_map_iov_to_sgl(struct tcm_vhost_cmd *tv_cmd,
 493         struct iovec *iov, unsigned int niov, int write)
 494 {
 495         int ret;
 496         unsigned int i;
 497         u32 sgl_count;
 498         struct scatterlist *sg;
 499
 500         /*
 501          * Find out how long sglist needs to be
 502          */
 503         sgl_count = 0;
 504         for (i = 0; i < niov; i++)
 505                 sgl_count += iov_num_pages(&iov[i]);
 506
 507         /* TODO overflow checking */
 508
 509         sg = kmalloc(sizeof(tv_cmd->tvc_sgl[0]) * sgl_count, GFP_ATOMIC);
 510         if (!sg)
 511                 return -ENOMEM;
 512         pr_debug("%s sg %p sgl_count %u is_err %d\n", __func__,
 513                sg, sgl_count, !sg);
 514         sg_init_table(sg, sgl_count);
 515
 516         tv_cmd->tvc_sgl = sg;
 517         tv_cmd->tvc_sgl_count = sgl_count;
 518
 519         pr_debug("Mapping %u iovecs for %u pages\n", niov, sgl_count);
 520         for (i = 0; i < niov; i++) {
 521                 ret = vhost_scsi_map_to_sgl(sg, sgl_count, &iov[i], write);
 522                 if (ret < 0) {
 523                         for (i = 0; i < tv_cmd->tvc_sgl_count; i++)
 524                                 put_page(sg_page(&tv_cmd->tvc_sgl[i]));
 525                         kfree(tv_cmd->tvc_sgl);
 526                         tv_cmd->tvc_sgl = NULL;
 527                         tv_cmd->tvc_sgl_count = 0;
 528                         return ret;
 529                 }
 530
 531                 sg += ret;
 532                 sgl_count -= ret;
 533         }
 534         return 0;
 535 }
 536
 537 static void tcm_vhost_submission_work(struct work_struct *work)
 538 {
 539         struct tcm_vhost_cmd *tv_cmd =
 540                 container_of(work, struct tcm_vhost_cmd, work);
 541         struct tcm_vhost_nexus *tv_nexus;
 542         struct se_cmd *se_cmd = &tv_cmd->tvc_se_cmd;
 543         struct scatterlist *sg_ptr, *sg_bidi_ptr = NULL;
 544         int rc, sg_no_bidi = 0;
 545
 546         if (tv_cmd->tvc_sgl_count) {
 547                 sg_ptr = tv_cmd->tvc_sgl;
 548 /* FIXME: Fix BIDI operation in tcm_vhost_submission_work() */
 549 #if 0
 550                 if (se_cmd->se_cmd_flags & SCF_BIDI) {
 551                         sg_bidi_ptr = NULL;
 552                         sg_no_bidi = 0;
 553                 }
 554 #endif
 555         } else {
 556                 sg_ptr = NULL;
 557         }
 558         tv_nexus = tv_cmd->tvc_nexus;
 559
 560         rc = target_submit_cmd_map_sgls(se_cmd, tv_nexus->tvn_se_sess,
 561                         tv_cmd->tvc_cdb, &tv_cmd->tvc_sense_buf[0],
 562                         tv_cmd->tvc_lun, tv_cmd->tvc_exp_data_len,
 563                         tv_cmd->tvc_task_attr, tv_cmd->tvc_data_direction,
 564                         0, sg_ptr, tv_cmd->tvc_sgl_count,
 565                         sg_bidi_ptr, sg_no_bidi);
 566         if (rc < 0) {
 567                 transport_send_check_condition_and_sense(se_cmd,
 568                                 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
 569                 transport_generic_free_cmd(se_cmd, 0);
 570         }
 571 }
 572
 573 static void vhost_scsi_handle_vq(struct vhost_scsi *vs,
 574         struct vhost_virtqueue *vq)
 575 {
 576         struct virtio_scsi_cmd_req v_req;
 577         struct tcm_vhost_tpg *tv_tpg;
 578         struct tcm_vhost_cmd *tv_cmd;
 579         u32 exp_data_len, data_first, data_num, data_direction;
 580         unsigned out, in, i;
 581         int head, ret;
 582         u8 target;
 583
 584         /* Must use ioctl VHOST_SCSI_SET_ENDPOINT */
 585         if (unlikely(!vs->vs_endpoint))
 586                 return;
 587
 588         mutex_lock(&vq->mutex);
 589         vhost_disable_notify(&vs->dev, vq);
 590
 591         for (;;) {
 592                 head = vhost_get_vq_desc(&vs->dev, vq, vq->iov,
 593                                         ARRAY_SIZE(vq->iov), &out, &in,
 594                                         NULL, NULL);
 595                 pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n",
 596                                         head, out, in);
 597                 /* On error, stop handling until the next kick. */
 598                 if (unlikely(head < 0))
 599                         break;
 600                 /* Nothing new?  Wait for eventfd to tell us they refilled. */
 601                 if (head == vq->num) {
 602                         if (unlikely(vhost_enable_notify(&vs->dev, vq))) {
 603                                 vhost_disable_notify(&vs->dev, vq);
 604                                 continue;
 605                         }
 606                         break;
 607                 }
 608
 609 /* FIXME: BIDI operation */
 610                 if (out == 1 && in == 1) {
 611                         data_direction = DMA_NONE;
 612                         data_first = 0;
 613                         data_num = 0;
 614                 } else if (out == 1 && in > 1) {
 615                         data_direction = DMA_FROM_DEVICE;
 616                         data_first = out + 1;
 617                         data_num = in - 1;
 618                 } else if (out > 1 && in == 1) {
 619                         data_direction = DMA_TO_DEVICE;
 620                         data_first = 1;
 621                         data_num = out - 1;
 622                 } else {
 623                         vq_err(vq, "Invalid buffer layout out: %u in: %u\n",
 624                                         out, in);
 625                         break;
 626                 }
 627
 628                 /*
 629                  * Check for a sane resp buffer so we can report errors to
 630                  * the guest.
 631                  */
 632                 if (unlikely(vq->iov[out].iov_len !=
 633                                         sizeof(struct virtio_scsi_cmd_resp))) {
 634                         vq_err(vq, "Expecting virtio_scsi_cmd_resp, got %zu"
 635                                 " bytes\n", vq->iov[out].iov_len);
 636                         break;
 637                 }
 638
 639                 if (unlikely(vq->iov[0].iov_len != sizeof(v_req))) {
 640                         vq_err(vq, "Expecting virtio_scsi_cmd_req, got %zu"
 641                                 " bytes\n", vq->iov[0].iov_len);
 642                         break;
 643                 }
 644                 pr_debug("Calling __copy_from_user: vq->iov[0].iov_base: %p,"
 645                         " len: %zu\n", vq->iov[0].iov_base, sizeof(v_req));
 646                 ret = __copy_from_user(&v_req, vq->iov[0].iov_base,
 647                                 sizeof(v_req));
 648                 if (unlikely(ret)) {
 649                         vq_err(vq, "Faulted on virtio_scsi_cmd_req\n");
 650                         break;
 651                 }
 652
 653                 /* Extract the tpgt */
 654                 target = v_req.lun[1];
 655                 tv_tpg = vs->vs_tpg[target];
 656
 657                 /* Target does not exist, fail the request */
 658                 if (unlikely(!tv_tpg)) {
 659                         struct virtio_scsi_cmd_resp __user *resp;
 660                         struct virtio_scsi_cmd_resp rsp;
 661
 662                         memset(&rsp, 0, sizeof(rsp));
 663                         rsp.response = VIRTIO_SCSI_S_BAD_TARGET;
 664                         resp = vq->iov[out].iov_base;
 665                         ret = __copy_to_user(resp, &rsp, sizeof(rsp));
 666                         if (!ret)
 667                                 vhost_add_used_and_signal(&vs->dev,
 668                                                           vq, head, 0);
 669                         else
 670                                 pr_err("Faulted on virtio_scsi_cmd_resp\n");
 671
 672                         continue;
 673                 }
 674
 675                 exp_data_len = 0;
 676                 for (i = 0; i < data_num; i++)
 677                         exp_data_len += vq->iov[data_first + i].iov_len;
 678
 679                 tv_cmd = vhost_scsi_allocate_cmd(tv_tpg, &v_req,
 680                                         exp_data_len, data_direction);
 681                 if (IS_ERR(tv_cmd)) {
 682                         vq_err(vq, "vhost_scsi_allocate_cmd failed %ld\n",
 683                                         PTR_ERR(tv_cmd));
 684                         break;
 685                 }
 686                 pr_debug("Allocated tv_cmd: %p exp_data_len: %d, data_direction"
 687                         ": %d\n", tv_cmd, exp_data_len, data_direction);
 688
 689                 tv_cmd->tvc_vhost = vs;
 690                 tv_cmd->tvc_vq = vq;
 691
 692                 if (unlikely(vq->iov[out].iov_len !=
 693                                 sizeof(struct virtio_scsi_cmd_resp))) {
 694                         vq_err(vq, "Expecting virtio_scsi_cmd_resp, got %zu"
 695                                 " bytes, out: %d, in: %d\n",
 696                                 vq->iov[out].iov_len, out, in);
 697                         break;
 698                 }
 699
 700                 tv_cmd->tvc_resp = vq->iov[out].iov_base;
 701
 702                 /*
 703                  * Copy in the recieved CDB descriptor into tv_cmd->tvc_cdb
 704                  * that will be used by tcm_vhost_new_cmd_map() and down into
 705                  * target_setup_cmd_from_cdb()
 706                  */
 707                 memcpy(tv_cmd->tvc_cdb, v_req.cdb, TCM_VHOST_MAX_CDB_SIZE);
 708                 /*
 709                  * Check that the recieved CDB size does not exceeded our
 710                  * hardcoded max for tcm_vhost
 711                  */
 712                 /* TODO what if cdb was too small for varlen cdb header? */
 713                 if (unlikely(scsi_command_size(tv_cmd->tvc_cdb) >
 714                                         TCM_VHOST_MAX_CDB_SIZE)) {
 715                         vq_err(vq, "Received SCSI CDB with command_size: %d that"
 716                                 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
 717                                 scsi_command_size(tv_cmd->tvc_cdb),
 718                                 TCM_VHOST_MAX_CDB_SIZE);
 719                         break; /* TODO */
 720                 }
 721                 tv_cmd->tvc_lun = ((v_req.lun[2] << 8) | v_req.lun[3]) & 0x3FFF;
 722
 723                 pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n",
 724                         tv_cmd->tvc_cdb[0], tv_cmd->tvc_lun);
 725
 726                 if (data_direction != DMA_NONE) {
 727                         ret = vhost_scsi_map_iov_to_sgl(tv_cmd,
 728                                         &vq->iov[data_first], data_num,
 729                                         data_direction == DMA_TO_DEVICE);
 730                         if (unlikely(ret)) {
 731                                 vq_err(vq, "Failed to map iov to sgl\n");
 732                                 break; /* TODO */
 733                         }
 734                 }
 735
 736                 /*
 737                  * Save the descriptor from vhost_get_vq_desc() to be used to
 738                  * complete the virtio-scsi request in TCM callback context via
 739                  * tcm_vhost_queue_data_in() and tcm_vhost_queue_status()
 740                  */
 741                 tv_cmd->tvc_vq_desc = head;
 742                 /*
 743                  * Dispatch tv_cmd descriptor for cmwq execution in process
 744                  * context provided by tcm_vhost_workqueue.  This also ensures
 745                  * tv_cmd is executed on the same kworker CPU as this vhost
 746                  * thread to gain positive L2 cache locality effects..
 747                  */
 748                 INIT_WORK(&tv_cmd->work, tcm_vhost_submission_work);
 749                 queue_work(tcm_vhost_workqueue, &tv_cmd->work);
 750         }
 751
 752         mutex_unlock(&vq->mutex);
 753 }
 754
 755 static void vhost_scsi_ctl_handle_kick(struct vhost_work *work)
 756 {
 757         pr_debug("%s: The handling func for control queue.\n", __func__);
 758 }
 759
 760 static void vhost_scsi_evt_handle_kick(struct vhost_work *work)
 761 {
 762         pr_debug("%s: The handling func for event queue.\n", __func__);
 763 }
 764
 765 static void vhost_scsi_handle_kick(struct vhost_work *work)
 766 {
 767         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
 768                                                 poll.work);
 769         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
 770
 771         vhost_scsi_handle_vq(vs, vq);
 772 }
 773
 774 /*
 775  * Called from vhost_scsi_ioctl() context to walk the list of available
 776  * tcm_vhost_tpg with an active struct tcm_vhost_nexus
 777  */
 778 static int vhost_scsi_set_endpoint(
 779         struct vhost_scsi *vs,
 780         struct vhost_scsi_target *t)
 781 {
 782         struct tcm_vhost_tport *tv_tport;
 783         struct tcm_vhost_tpg *tv_tpg;
 784         bool match = false;
 785         int index, ret;
 786
 787         mutex_lock(&vs->dev.mutex);
 788         /* Verify that ring has been setup correctly. */
 789         for (index = 0; index < vs->dev.nvqs; ++index) {
 790                 /* Verify that ring has been setup correctly. */
 791                 if (!vhost_vq_access_ok(&vs->vqs[index])) {
 792                         mutex_unlock(&vs->dev.mutex);
 793                         return -EFAULT;
 794                 }
 795         }
 796
 797         mutex_lock(&tcm_vhost_mutex);
 798         list_for_each_entry(tv_tpg, &tcm_vhost_list, tv_tpg_list) {
 799                 mutex_lock(&tv_tpg->tv_tpg_mutex);
 800                 if (!tv_tpg->tpg_nexus) {
 801                         mutex_unlock(&tv_tpg->tv_tpg_mutex);
 802                         continue;
 803                 }
 804                 if (tv_tpg->tv_tpg_vhost_count != 0) {
 805                         mutex_unlock(&tv_tpg->tv_tpg_mutex);
 806                         continue;
 807                 }
 808                 tv_tport = tv_tpg->tport;
 809
 810                 if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
 811                         if (vs->vs_tpg[tv_tpg->tport_tpgt]) {
 812                                 mutex_unlock(&tv_tpg->tv_tpg_mutex);
 813                                 mutex_unlock(&tcm_vhost_mutex);
 814                                 mutex_unlock(&vs->dev.mutex);
 815                                 return -EEXIST;
 816                         }
 817                         tv_tpg->tv_tpg_vhost_count++;
 818                         vs->vs_tpg[tv_tpg->tport_tpgt] = tv_tpg;
 819                         smp_mb__after_atomic_inc();
 820                         match = true;
 821                 }
 822                 mutex_unlock(&tv_tpg->tv_tpg_mutex);
 823         }
 824         mutex_unlock(&tcm_vhost_mutex);
 825
 826         if (match) {
 827                 memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
 828                        sizeof(vs->vs_vhost_wwpn));
 829                 vs->vs_endpoint = true;
 830                 ret = 0;
 831         } else {
 832                 ret = -EEXIST;
 833         }
 834
 835         mutex_unlock(&vs->dev.mutex);
 836         return ret;
 837 }
 838
 839 static int vhost_scsi_clear_endpoint(
 840         struct vhost_scsi *vs,
 841         struct vhost_scsi_target *t)
 842 {
 843         struct tcm_vhost_tport *tv_tport;
 844         struct tcm_vhost_tpg *tv_tpg;
 845         int index, ret, i;
 846         u8 target;
 847
 848         mutex_lock(&vs->dev.mutex);
 849         /* Verify that ring has been setup correctly. */
 850         for (index = 0; index < vs->dev.nvqs; ++index) {
 851                 if (!vhost_vq_access_ok(&vs->vqs[index])) {
 852                         ret = -EFAULT;
 853                         goto err_dev;
 854                 }
 855         }
 856         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
 857                 target = i;
 858
 859                 tv_tpg = vs->vs_tpg[target];
 860                 if (!tv_tpg)
 861                         continue;
 862
 863                 mutex_lock(&tv_tpg->tv_tpg_mutex);
 864                 tv_tport = tv_tpg->tport;
 865                 if (!tv_tport) {
 866                         ret = -ENODEV;
 867                         goto err_tpg;
 868                 }
 869
 870                 if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
 871                         pr_warn("tv_tport->tport_name: %s, tv_tpg->tport_tpgt: %hu"
 872                                 " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
 873                                 tv_tport->tport_name, tv_tpg->tport_tpgt,
 874                                 t->vhost_wwpn, t->vhost_tpgt);
 875                         ret = -EINVAL;
 876                         goto err_tpg;
 877                 }
 878                 tv_tpg->tv_tpg_vhost_count--;
 879                 vs->vs_tpg[target] = NULL;
 880                 vs->vs_endpoint = false;
 881                 mutex_unlock(&tv_tpg->tv_tpg_mutex);
 882         }
 883         mutex_unlock(&vs->dev.mutex);
 884         return 0;
 885
 886 err_tpg:
 887         mutex_unlock(&tv_tpg->tv_tpg_mutex);
 888 err_dev:
 889         mutex_unlock(&vs->dev.mutex);
 890         return ret;
 891 }
 892
 893 static int vhost_scsi_open(struct inode *inode, struct file *f)
 894 {
 895         struct vhost_scsi *s;
 896         int r, i;
 897
 898         s = kzalloc(sizeof(*s), GFP_KERNEL);
 899         if (!s)
 900                 return -ENOMEM;
 901
 902         vhost_work_init(&s->vs_completion_work, vhost_scsi_complete_cmd_work);
 903
 904         s->vqs[VHOST_SCSI_VQ_CTL].handle_kick = vhost_scsi_ctl_handle_kick;
 905         s->vqs[VHOST_SCSI_VQ_EVT].handle_kick = vhost_scsi_evt_handle_kick;
 906         for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++)
 907                 s->vqs[i].handle_kick = vhost_scsi_handle_kick;
 908         r = vhost_dev_init(&s->dev, s->vqs, VHOST_SCSI_MAX_VQ);
 909         if (r < 0) {
 910                 kfree(s);
 911                 return r;
 912         }
 913
 914         f->private_data = s;
 915         return 0;
 916 }
 917
 918 static int vhost_scsi_release(struct inode *inode, struct file *f)
 919 {
 920         struct vhost_scsi *s = f->private_data;
 921         struct vhost_scsi_target t;
 922
 923         mutex_lock(&s->dev.mutex);
 924         memcpy(t.vhost_wwpn, s->vs_vhost_wwpn, sizeof(t.vhost_wwpn));
 925         mutex_unlock(&s->dev.mutex);
 926         vhost_scsi_clear_endpoint(s, &t);
 927         vhost_dev_stop(&s->dev);
 928         vhost_dev_cleanup(&s->dev, false);
 929         kfree(s);
 930         return 0;
 931 }
 932
 933 static void vhost_scsi_flush_vq(struct vhost_scsi *vs, int index)
 934 {
 935         vhost_poll_flush(&vs->dev.vqs[index].poll);
 936 }
 937
 938 static void vhost_scsi_flush(struct vhost_scsi *vs)
 939 {
 940         int i;
 941
 942         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
 943                 vhost_scsi_flush_vq(vs, i);
 944         vhost_work_flush(&vs->dev, &vs->vs_completion_work);
 945 }
 946
 947 static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features)
 948 {
 949         if (features & ~VHOST_FEATURES)
 950                 return -EOPNOTSUPP;
 951
 952         mutex_lock(&vs->dev.mutex);
 953         if ((features & (1 << VHOST_F_LOG_ALL)) &&
 954             !vhost_log_access_ok(&vs->dev)) {
 955                 mutex_unlock(&vs->dev.mutex);
 956                 return -EFAULT;
 957         }
 958         vs->dev.acked_features = features;
 959         smp_wmb();
 960         vhost_scsi_flush(vs);
 961         mutex_unlock(&vs->dev.mutex);
 962         return 0;
 963 }
 964
 965 static long vhost_scsi_ioctl(struct file *f, unsigned int ioctl,
 966                                 unsigned long arg)
 967 {
 968         struct vhost_scsi *vs = f->private_data;
 969         struct vhost_scsi_target backend;
 970         void __user *argp = (void __user *)arg;
 971         u64 __user *featurep = argp;
 972         u64 features;
 973         int r, abi_version = VHOST_SCSI_ABI_VERSION;
 974
 975         switch (ioctl) {
 976         case VHOST_SCSI_SET_ENDPOINT:
 977                 if (copy_from_user(&backend, argp, sizeof backend))
 978                         return -EFAULT;
 979                 if (backend.reserved != 0)
 980                         return -EOPNOTSUPP;
 981
 982                 return vhost_scsi_set_endpoint(vs, &backend);
 983         case VHOST_SCSI_CLEAR_ENDPOINT:
 984                 if (copy_from_user(&backend, argp, sizeof backend))
 985                         return -EFAULT;
 986                 if (backend.reserved != 0)
 987                         return -EOPNOTSUPP;
 988
 989                 return vhost_scsi_clear_endpoint(vs, &backend);
 990         case VHOST_SCSI_GET_ABI_VERSION:
 991                 if (copy_to_user(argp, &abi_version, sizeof abi_version))
 992                         return -EFAULT;
 993                 return 0;
 994         case VHOST_GET_FEATURES:
 995                 features = VHOST_FEATURES;
 996                 if (copy_to_user(featurep, &features, sizeof features))
 997                         return -EFAULT;
 998                 return 0;
 999         case VHOST_SET_FEATURES:
1000                 if (copy_from_user(&features, featurep, sizeof features))
1001                         return -EFAULT;
1002                 return vhost_scsi_set_features(vs, features);
1003         default:
1004                 mutex_lock(&vs->dev.mutex);
1005                 r = vhost_dev_ioctl(&vs->dev, ioctl, argp);
1006                 /* TODO: flush backend after dev ioctl. */
1007                 if (r == -ENOIOCTLCMD)
1008                         r = vhost_vring_ioctl(&vs->dev, ioctl, argp);
1009                 mutex_unlock(&vs->dev.mutex);
1010                 return r;
1011         }
1012 }
1013
1014 #ifdef CONFIG_COMPAT
1015 static long vhost_scsi_compat_ioctl(struct file *f, unsigned int ioctl,
1016                                 unsigned long arg)
1017 {
1018         return vhost_scsi_ioctl(f, ioctl, (unsigned long)compat_ptr(arg));
1019 }
1020 #endif
1021
1022 static const struct file_operations vhost_scsi_fops = {
1023         .owner          = THIS_MODULE,
1024         .release        = vhost_scsi_release,
1025         .unlocked_ioctl = vhost_scsi_ioctl,
1026 #ifdef CONFIG_COMPAT
1027         .compat_ioctl   = vhost_scsi_compat_ioctl,
1028 #endif
1029         .open           = vhost_scsi_open,
1030         .llseek         = noop_llseek,
1031 };
1032
1033 static struct miscdevice vhost_scsi_misc = {
1034         MISC_DYNAMIC_MINOR,
1035         "vhost-scsi",
1036         &vhost_scsi_fops,
1037 };
1038
1039 static int __init vhost_scsi_register(void)
1040 {
1041         return misc_register(&vhost_scsi_misc);
1042 }
1043
1044 static int vhost_scsi_deregister(void)
1045 {
1046         return misc_deregister(&vhost_scsi_misc);
1047 }
1048
1049 static char *tcm_vhost_dump_proto_id(struct tcm_vhost_tport *tport)
1050 {
1051         switch (tport->tport_proto_id) {
1052         case SCSI_PROTOCOL_SAS:
1053                 return "SAS";
1054         case SCSI_PROTOCOL_FCP:
1055                 return "FCP";
1056         case SCSI_PROTOCOL_ISCSI:
1057                 return "iSCSI";
1058         default:
1059                 break;
1060         }
1061
1062         return "Unknown";
1063 }
1064
1065 static int tcm_vhost_port_link(struct se_portal_group *se_tpg,
1066         struct se_lun *lun)
1067 {
1068         struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg,
1069                                 struct tcm_vhost_tpg, se_tpg);
1070
1071         mutex_lock(&tv_tpg->tv_tpg_mutex);
1072         tv_tpg->tv_tpg_port_count++;
1073         mutex_unlock(&tv_tpg->tv_tpg_mutex);
1074
1075         return 0;
1076 }
1077
1078 static void tcm_vhost_port_unlink(struct se_portal_group *se_tpg,
1079         struct se_lun *se_lun)
1080 {
1081         struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg,
1082                                 struct tcm_vhost_tpg, se_tpg);
1083
1084         mutex_lock(&tv_tpg->tv_tpg_mutex);
1085         tv_tpg->tv_tpg_port_count--;
1086         mutex_unlock(&tv_tpg->tv_tpg_mutex);
1087 }
1088
1089 static struct se_node_acl *tcm_vhost_make_nodeacl(
1090         struct se_portal_group *se_tpg,
1091         struct config_group *group,
1092         const char *name)
1093 {
1094         struct se_node_acl *se_nacl, *se_nacl_new;
1095         struct tcm_vhost_nacl *nacl;
1096         u64 wwpn = 0;
1097         u32 nexus_depth;
1098
1099         /* tcm_vhost_parse_wwn(name, &wwpn, 1) < 0)
1100                 return ERR_PTR(-EINVAL); */
1101         se_nacl_new = tcm_vhost_alloc_fabric_acl(se_tpg);
1102         if (!se_nacl_new)
1103                 return ERR_PTR(-ENOMEM);
1104
1105         nexus_depth = 1;
1106         /*
1107          * se_nacl_new may be released by core_tpg_add_initiator_node_acl()
1108          * when converting a NodeACL from demo mode -> explict
1109          */
1110         se_nacl = core_tpg_add_initiator_node_acl(se_tpg, se_nacl_new,
1111                                 name, nexus_depth);
1112         if (IS_ERR(se_nacl)) {
1113                 tcm_vhost_release_fabric_acl(se_tpg, se_nacl_new);
1114                 return se_nacl;
1115         }
1116         /*
1117          * Locate our struct tcm_vhost_nacl and set the FC Nport WWPN
1118          */
1119         nacl = container_of(se_nacl, struct tcm_vhost_nacl, se_node_acl);
1120         nacl->iport_wwpn = wwpn;
1121
1122         return se_nacl;
1123 }
1124
1125 static void tcm_vhost_drop_nodeacl(struct se_node_acl *se_acl)
1126 {
1127         struct tcm_vhost_nacl *nacl = container_of(se_acl,
1128                                 struct tcm_vhost_nacl, se_node_acl);
1129         core_tpg_del_initiator_node_acl(se_acl->se_tpg, se_acl, 1);
1130         kfree(nacl);
1131 }
1132
1133 static int tcm_vhost_make_nexus(struct tcm_vhost_tpg *tv_tpg,
1134         const char *name)
1135 {
1136         struct se_portal_group *se_tpg;
1137         struct tcm_vhost_nexus *tv_nexus;
1138
1139         mutex_lock(&tv_tpg->tv_tpg_mutex);
1140         if (tv_tpg->tpg_nexus) {
1141                 mutex_unlock(&tv_tpg->tv_tpg_mutex);
1142                 pr_debug("tv_tpg->tpg_nexus already exists\n");
1143                 return -EEXIST;
1144         }
1145         se_tpg = &tv_tpg->se_tpg;
1146
1147         tv_nexus = kzalloc(sizeof(struct tcm_vhost_nexus), GFP_KERNEL);
1148         if (!tv_nexus) {
1149                 mutex_unlock(&tv_tpg->tv_tpg_mutex);
1150                 pr_err("Unable to allocate struct tcm_vhost_nexus\n");
1151                 return -ENOMEM;
1152         }
1153         /*
1154          *  Initialize the struct se_session pointer
1155          */
1156         tv_nexus->tvn_se_sess = transport_init_session();
1157         if (IS_ERR(tv_nexus->tvn_se_sess)) {
1158                 mutex_unlock(&tv_tpg->tv_tpg_mutex);
1159                 kfree(tv_nexus);
1160                 return -ENOMEM;
1161         }
1162         /*
1163          * Since we are running in 'demo mode' this call with generate a
1164          * struct se_node_acl for the tcm_vhost struct se_portal_group with
1165          * the SCSI Initiator port name of the passed configfs group 'name'.
1166          */
1167         tv_nexus->tvn_se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
1168                                 se_tpg, (unsigned char *)name);
1169         if (!tv_nexus->tvn_se_sess->se_node_acl) {
1170                 mutex_unlock(&tv_tpg->tv_tpg_mutex);
1171                 pr_debug("core_tpg_check_initiator_node_acl() failed"
1172                                 " for %s\n", name);
1173                 transport_free_session(tv_nexus->tvn_se_sess);
1174                 kfree(tv_nexus);
1175                 return -ENOMEM;
1176         }
1177         /*
1178          * Now register the TCM vhost virtual I_T Nexus as active with the
1179          * call to __transport_register_session()
1180          */
1181         __transport_register_session(se_tpg, tv_nexus->tvn_se_sess->se_node_acl,
1182                         tv_nexus->tvn_se_sess, tv_nexus);
1183         tv_tpg->tpg_nexus = tv_nexus;
1184
1185         mutex_unlock(&tv_tpg->tv_tpg_mutex);
1186         return 0;
1187 }
1188
1189 static int tcm_vhost_drop_nexus(struct tcm_vhost_tpg *tpg)
1190 {
1191         struct se_session *se_sess;
1192         struct tcm_vhost_nexus *tv_nexus;
1193
1194         mutex_lock(&tpg->tv_tpg_mutex);
1195         tv_nexus = tpg->tpg_nexus;
1196         if (!tv_nexus) {
1197                 mutex_unlock(&tpg->tv_tpg_mutex);
1198                 return -ENODEV;
1199         }
1200
1201         se_sess = tv_nexus->tvn_se_sess;
1202         if (!se_sess) {
1203                 mutex_unlock(&tpg->tv_tpg_mutex);
1204                 return -ENODEV;
1205         }
1206
1207         if (tpg->tv_tpg_port_count != 0) {
1208                 mutex_unlock(&tpg->tv_tpg_mutex);
1209                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
1210                         " active TPG port count: %d\n",
1211                         tpg->tv_tpg_port_count);
1212                 return -EBUSY;
1213         }
1214
1215         if (tpg->tv_tpg_vhost_count != 0) {
1216                 mutex_unlock(&tpg->tv_tpg_mutex);
1217                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
1218                         " active TPG vhost count: %d\n",
1219                         tpg->tv_tpg_vhost_count);
1220                 return -EBUSY;
1221         }
1222
1223         pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated"
1224                 " %s Initiator Port: %s\n", tcm_vhost_dump_proto_id(tpg->tport),
1225                 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1226         /*
1227          * Release the SCSI I_T Nexus to the emulated vhost Target Port
1228          */
1229         transport_deregister_session(tv_nexus->tvn_se_sess);
1230         tpg->tpg_nexus = NULL;
1231         mutex_unlock(&tpg->tv_tpg_mutex);
1232
1233         kfree(tv_nexus);
1234         return 0;
1235 }
1236
1237 static ssize_t tcm_vhost_tpg_show_nexus(struct se_portal_group *se_tpg,
1238         char *page)
1239 {
1240         struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg,
1241                                 struct tcm_vhost_tpg, se_tpg);
1242         struct tcm_vhost_nexus *tv_nexus;
1243         ssize_t ret;
1244
1245         mutex_lock(&tv_tpg->tv_tpg_mutex);
1246         tv_nexus = tv_tpg->tpg_nexus;
1247         if (!tv_nexus) {
1248                 mutex_unlock(&tv_tpg->tv_tpg_mutex);
1249                 return -ENODEV;
1250         }
1251         ret = snprintf(page, PAGE_SIZE, "%s\n",
1252                         tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1253         mutex_unlock(&tv_tpg->tv_tpg_mutex);
1254
1255         return ret;
1256 }
1257
1258 static ssize_t tcm_vhost_tpg_store_nexus(struct se_portal_group *se_tpg,
1259         const char *page,
1260         size_t count)
1261 {
1262         struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg,
1263                                 struct tcm_vhost_tpg, se_tpg);
1264         struct tcm_vhost_tport *tport_wwn = tv_tpg->tport;
1265         unsigned char i_port[TCM_VHOST_NAMELEN], *ptr, *port_ptr;
1266         int ret;
1267         /*
1268          * Shutdown the active I_T nexus if 'NULL' is passed..
1269          */
1270         if (!strncmp(page, "NULL", 4)) {
1271                 ret = tcm_vhost_drop_nexus(tv_tpg);
1272                 return (!ret) ? count : ret;
1273         }
1274         /*
1275          * Otherwise make sure the passed virtual Initiator port WWN matches
1276          * the fabric protocol_id set in tcm_vhost_make_tport(), and call
1277          * tcm_vhost_make_nexus().
1278          */
1279         if (strlen(page) >= TCM_VHOST_NAMELEN) {
1280                 pr_err("Emulated NAA Sas Address: %s, exceeds"
1281                                 " max: %d\n", page, TCM_VHOST_NAMELEN);
1282                 return -EINVAL;
1283         }
1284         snprintf(&i_port[0], TCM_VHOST_NAMELEN, "%s", page);
1285
1286         ptr = strstr(i_port, "naa.");
1287         if (ptr) {
1288                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
1289                         pr_err("Passed SAS Initiator Port %s does not"
1290                                 " match target port protoid: %s\n", i_port,
1291                                 tcm_vhost_dump_proto_id(tport_wwn));
1292                         return -EINVAL;
1293                 }
1294                 port_ptr = &i_port[0];
1295                 goto check_newline;
1296         }
1297         ptr = strstr(i_port, "fc.");
1298         if (ptr) {
1299                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
1300                         pr_err("Passed FCP Initiator Port %s does not"
1301                                 " match target port protoid: %s\n", i_port,
1302                                 tcm_vhost_dump_proto_id(tport_wwn));
1303                         return -EINVAL;
1304                 }
1305                 port_ptr = &i_port[3]; /* Skip over "fc." */
1306                 goto check_newline;
1307         }
1308         ptr = strstr(i_port, "iqn.");
1309         if (ptr) {
1310                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
1311                         pr_err("Passed iSCSI Initiator Port %s does not"
1312                                 " match target port protoid: %s\n", i_port,
1313                                 tcm_vhost_dump_proto_id(tport_wwn));
1314                         return -EINVAL;
1315                 }
1316                 port_ptr = &i_port[0];
1317                 goto check_newline;
1318         }
1319         pr_err("Unable to locate prefix for emulated Initiator Port:"
1320                         " %s\n", i_port);
1321         return -EINVAL;
1322         /*
1323          * Clear any trailing newline for the NAA WWN
1324          */
1325 check_newline:
1326         if (i_port[strlen(i_port)-1] == '\n')
1327                 i_port[strlen(i_port)-1] = '\0';
1328
1329         ret = tcm_vhost_make_nexus(tv_tpg, port_ptr);
1330         if (ret < 0)
1331                 return ret;
1332
1333         return count;
1334 }
1335
1336 TF_TPG_BASE_ATTR(tcm_vhost, nexus, S_IRUGO | S_IWUSR);
1337
1338 static struct configfs_attribute *tcm_vhost_tpg_attrs[] = {
1339         &tcm_vhost_tpg_nexus.attr,
1340         NULL,
1341 };
1342
1343 static struct se_portal_group *tcm_vhost_make_tpg(struct se_wwn *wwn,
1344         struct config_group *group,
1345         const char *name)
1346 {
1347         struct tcm_vhost_tport *tport = container_of(wwn,
1348                         struct tcm_vhost_tport, tport_wwn);
1349
1350         struct tcm_vhost_tpg *tpg;
1351         unsigned long tpgt;
1352         int ret;
1353
1354         if (strstr(name, "tpgt_") != name)
1355                 return ERR_PTR(-EINVAL);
1356         if (kstrtoul(name + 5, 10, &tpgt) || tpgt > UINT_MAX)
1357                 return ERR_PTR(-EINVAL);
1358
1359         tpg = kzalloc(sizeof(struct tcm_vhost_tpg), GFP_KERNEL);
1360         if (!tpg) {
1361                 pr_err("Unable to allocate struct tcm_vhost_tpg");
1362                 return ERR_PTR(-ENOMEM);
1363         }
1364         mutex_init(&tpg->tv_tpg_mutex);
1365         INIT_LIST_HEAD(&tpg->tv_tpg_list);
1366         tpg->tport = tport;
1367         tpg->tport_tpgt = tpgt;
1368
1369         ret = core_tpg_register(&tcm_vhost_fabric_configfs->tf_ops, wwn,
1370                                 &tpg->se_tpg, tpg, TRANSPORT_TPG_TYPE_NORMAL);
1371         if (ret < 0) {
1372                 kfree(tpg);
1373                 return NULL;
1374         }
1375         mutex_lock(&tcm_vhost_mutex);
1376         list_add_tail(&tpg->tv_tpg_list, &tcm_vhost_list);
1377         mutex_unlock(&tcm_vhost_mutex);
1378
1379         return &tpg->se_tpg;
1380 }
1381
1382 static void tcm_vhost_drop_tpg(struct se_portal_group *se_tpg)
1383 {
1384         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1385                                 struct tcm_vhost_tpg, se_tpg);
1386
1387         mutex_lock(&tcm_vhost_mutex);
1388         list_del(&tpg->tv_tpg_list);
1389         mutex_unlock(&tcm_vhost_mutex);
1390         /*
1391          * Release the virtual I_T Nexus for this vhost TPG
1392          */
1393         tcm_vhost_drop_nexus(tpg);
1394         /*
1395          * Deregister the se_tpg from TCM..
1396          */
1397         core_tpg_deregister(se_tpg);
1398         kfree(tpg);
1399 }
1400
1401 static struct se_wwn *tcm_vhost_make_tport(struct target_fabric_configfs *tf,
1402         struct config_group *group,
1403         const char *name)
1404 {
1405         struct tcm_vhost_tport *tport;
1406         char *ptr;
1407         u64 wwpn = 0;
1408         int off = 0;
1409
1410         /* if (tcm_vhost_parse_wwn(name, &wwpn, 1) < 0)
1411                 return ERR_PTR(-EINVAL); */
1412
1413         tport = kzalloc(sizeof(struct tcm_vhost_tport), GFP_KERNEL);
1414         if (!tport) {
1415                 pr_err("Unable to allocate struct tcm_vhost_tport");
1416                 return ERR_PTR(-ENOMEM);
1417         }
1418         tport->tport_wwpn = wwpn;
1419         /*
1420          * Determine the emulated Protocol Identifier and Target Port Name
1421          * based on the incoming configfs directory name.
1422          */
1423         ptr = strstr(name, "naa.");
1424         if (ptr) {
1425                 tport->tport_proto_id = SCSI_PROTOCOL_SAS;
1426                 goto check_len;
1427         }
1428         ptr = strstr(name, "fc.");
1429         if (ptr) {
1430                 tport->tport_proto_id = SCSI_PROTOCOL_FCP;
1431                 off = 3; /* Skip over "fc." */
1432                 goto check_len;
1433         }
1434         ptr = strstr(name, "iqn.");
1435         if (ptr) {
1436                 tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
1437                 goto check_len;
1438         }
1439
1440         pr_err("Unable to locate prefix for emulated Target Port:"
1441                         " %s\n", name);
1442         kfree(tport);
1443         return ERR_PTR(-EINVAL);
1444
1445 check_len:
1446         if (strlen(name) >= TCM_VHOST_NAMELEN) {
1447                 pr_err("Emulated %s Address: %s, exceeds"
1448                         " max: %d\n", name, tcm_vhost_dump_proto_id(tport),
1449                         TCM_VHOST_NAMELEN);
1450                 kfree(tport);
1451                 return ERR_PTR(-EINVAL);
1452         }
1453         snprintf(&tport->tport_name[0], TCM_VHOST_NAMELEN, "%s", &name[off]);
1454
1455         pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target"
1456                 " %s Address: %s\n", tcm_vhost_dump_proto_id(tport), name);
1457
1458         return &tport->tport_wwn;
1459 }
1460
1461 static void tcm_vhost_drop_tport(struct se_wwn *wwn)
1462 {
1463         struct tcm_vhost_tport *tport = container_of(wwn,
1464                                 struct tcm_vhost_tport, tport_wwn);
1465
1466         pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target"
1467                 " %s Address: %s\n", tcm_vhost_dump_proto_id(tport),
1468                 tport->tport_name);
1469
1470         kfree(tport);
1471 }
1472
1473 static ssize_t tcm_vhost_wwn_show_attr_version(
1474         struct target_fabric_configfs *tf,
1475         char *page)
1476 {
1477         return sprintf(page, "TCM_VHOST fabric module %s on %s/%s"
1478                 "on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname,
1479                 utsname()->machine);
1480 }
1481
1482 TF_WWN_ATTR_RO(tcm_vhost, version);
1483
1484 static struct configfs_attribute *tcm_vhost_wwn_attrs[] = {
1485         &tcm_vhost_wwn_version.attr,
1486         NULL,
1487 };
1488
1489 static struct target_core_fabric_ops tcm_vhost_ops = {
1490         .get_fabric_name                = tcm_vhost_get_fabric_name,
1491         .get_fabric_proto_ident         = tcm_vhost_get_fabric_proto_ident,
1492         .tpg_get_wwn                    = tcm_vhost_get_fabric_wwn,
1493         .tpg_get_tag                    = tcm_vhost_get_tag,
1494         .tpg_get_default_depth          = tcm_vhost_get_default_depth,
1495         .tpg_get_pr_transport_id        = tcm_vhost_get_pr_transport_id,
1496         .tpg_get_pr_transport_id_len    = tcm_vhost_get_pr_transport_id_len,
1497         .tpg_parse_pr_out_transport_id  = tcm_vhost_parse_pr_out_transport_id,
1498         .tpg_check_demo_mode            = tcm_vhost_check_true,
1499         .tpg_check_demo_mode_cache      = tcm_vhost_check_true,
1500         .tpg_check_demo_mode_write_protect = tcm_vhost_check_false,
1501         .tpg_check_prod_mode_write_protect = tcm_vhost_check_false,
1502         .tpg_alloc_fabric_acl           = tcm_vhost_alloc_fabric_acl,
1503         .tpg_release_fabric_acl         = tcm_vhost_release_fabric_acl,
1504         .tpg_get_inst_index             = tcm_vhost_tpg_get_inst_index,
1505         .release_cmd                    = tcm_vhost_release_cmd,
1506         .shutdown_session               = tcm_vhost_shutdown_session,
1507         .close_session                  = tcm_vhost_close_session,
1508         .sess_get_index                 = tcm_vhost_sess_get_index,
1509         .sess_get_initiator_sid         = NULL,
1510         .write_pending                  = tcm_vhost_write_pending,
1511         .write_pending_status           = tcm_vhost_write_pending_status,
1512         .set_default_node_attributes    = tcm_vhost_set_default_node_attrs,
1513         .get_task_tag                   = tcm_vhost_get_task_tag,
1514         .get_cmd_state                  = tcm_vhost_get_cmd_state,
1515         .queue_data_in                  = tcm_vhost_queue_data_in,
1516         .queue_status                   = tcm_vhost_queue_status,
1517         .queue_tm_rsp                   = tcm_vhost_queue_tm_rsp,
1518         /*
1519          * Setup callers for generic logic in target_core_fabric_configfs.c
1520          */
1521         .fabric_make_wwn                = tcm_vhost_make_tport,
1522         .fabric_drop_wwn                = tcm_vhost_drop_tport,
1523         .fabric_make_tpg                = tcm_vhost_make_tpg,
1524         .fabric_drop_tpg                = tcm_vhost_drop_tpg,
1525         .fabric_post_link               = tcm_vhost_port_link,
1526         .fabric_pre_unlink              = tcm_vhost_port_unlink,
1527         .fabric_make_np                 = NULL,
1528         .fabric_drop_np                 = NULL,
1529         .fabric_make_nodeacl            = tcm_vhost_make_nodeacl,
1530         .fabric_drop_nodeacl            = tcm_vhost_drop_nodeacl,
1531 };
1532
1533 static int tcm_vhost_register_configfs(void)
1534 {
1535         struct target_fabric_configfs *fabric;
1536         int ret;
1537
1538         pr_debug("TCM_VHOST fabric module %s on %s/%s"
1539                 " on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname,
1540                 utsname()->machine);
1541         /*
1542          * Register the top level struct config_item_type with TCM core
1543          */
1544         fabric = target_fabric_configfs_init(THIS_MODULE, "vhost");
1545         if (IS_ERR(fabric)) {
1546                 pr_err("target_fabric_configfs_init() failed\n");
1547                 return PTR_ERR(fabric);
1548         }
1549         /*
1550          * Setup fabric->tf_ops from our local tcm_vhost_ops
1551          */
1552         fabric->tf_ops = tcm_vhost_ops;
1553         /*
1554          * Setup default attribute lists for various fabric->tf_cit_tmpl
1555          */
1556         TF_CIT_TMPL(fabric)->tfc_wwn_cit.ct_attrs = tcm_vhost_wwn_attrs;
1557         TF_CIT_TMPL(fabric)->tfc_tpg_base_cit.ct_attrs = tcm_vhost_tpg_attrs;
1558         TF_CIT_TMPL(fabric)->tfc_tpg_attrib_cit.ct_attrs = NULL;
1559         TF_CIT_TMPL(fabric)->tfc_tpg_param_cit.ct_attrs = NULL;
1560         TF_CIT_TMPL(fabric)->tfc_tpg_np_base_cit.ct_attrs = NULL;
1561         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_base_cit.ct_attrs = NULL;
1562         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_attrib_cit.ct_attrs = NULL;
1563         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_auth_cit.ct_attrs = NULL;
1564         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_param_cit.ct_attrs = NULL;
1565         /*
1566          * Register the fabric for use within TCM
1567          */
1568         ret = target_fabric_configfs_register(fabric);
1569         if (ret < 0) {
1570                 pr_err("target_fabric_configfs_register() failed"
1571                                 " for TCM_VHOST\n");
1572                 return ret;
1573         }
1574         /*
1575          * Setup our local pointer to *fabric
1576          */
1577         tcm_vhost_fabric_configfs = fabric;
1578         pr_debug("TCM_VHOST[0] - Set fabric -> tcm_vhost_fabric_configfs\n");
1579         return 0;
1580 };
1581
1582 static void tcm_vhost_deregister_configfs(void)
1583 {
1584         if (!tcm_vhost_fabric_configfs)
1585                 return;
1586
1587         target_fabric_configfs_deregister(tcm_vhost_fabric_configfs);
1588         tcm_vhost_fabric_configfs = NULL;
1589         pr_debug("TCM_VHOST[0] - Cleared tcm_vhost_fabric_configfs\n");
1590 };
1591
1592 static int __init tcm_vhost_init(void)
1593 {
1594         int ret = -ENOMEM;
1595         /*
1596          * Use our own dedicated workqueue for submitting I/O into
1597          * target core to avoid contention within system_wq.
1598          */
1599         tcm_vhost_workqueue = alloc_workqueue("tcm_vhost", 0, 0);
1600         if (!tcm_vhost_workqueue)
1601                 goto out;
1602
1603         ret = vhost_scsi_register();
1604         if (ret < 0)
1605                 goto out_destroy_workqueue;
1606
1607         ret = tcm_vhost_register_configfs();
1608         if (ret < 0)
1609                 goto out_vhost_scsi_deregister;
1610
1611         return 0;
1612
1613 out_vhost_scsi_deregister:
1614         vhost_scsi_deregister();
1615 out_destroy_workqueue:
1616         destroy_workqueue(tcm_vhost_workqueue);
1617 out:
1618         return ret;
1619 };
1620
1621 static void tcm_vhost_exit(void)
1622 {
1623         tcm_vhost_deregister_configfs();
1624         vhost_scsi_deregister();
1625         destroy_workqueue(tcm_vhost_workqueue);
1626 };
1627
1628 MODULE_DESCRIPTION("TCM_VHOST series fabric driver");
1629 MODULE_LICENSE("GPL");
1630 module_init(tcm_vhost_init);
1631 module_exit(tcm_vhost_exit);