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