1/*******************************************************************************
   2 * Vhost kernel TCM fabric driver for virtio SCSI initiators
   3 *
   4 * (C) Copyright 2010-2013 Datera, Inc.
   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@daterainc.com>
  10 *          Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
  11 *
  12 * This program is free software; you can redistribute it and/or modify
  13 * it under the terms of the GNU General Public License as published by
  14 * the Free Software Foundation; either version 2 of the License, or
  15 * (at your option) any later version.
  16 *
  17 * This program is distributed in the hope that it will be useful,
  18 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 * GNU General Public License for more details.
  21 *
  22 ****************************************************************************/
  23
  24#include <linux/module.h>
  25#include <linux/moduleparam.h>
  26#include <generated/utsrelease.h>
  27#include <linux/utsname.h>
  28#include <linux/init.h>
  29#include <linux/slab.h>
  30#include <linux/kthread.h>
  31#include <linux/types.h>
  32#include <linux/string.h>
  33#include <linux/configfs.h>
  34#include <linux/ctype.h>
  35#include <linux/compat.h>
  36#include <linux/eventfd.h>
  37#include <linux/fs.h>
 
  38#include <linux/miscdevice.h>
  39#include <asm/unaligned.h>
  40#include <scsi/scsi.h>
  41#include <scsi/scsi_tcq.h>
  42#include <target/target_core_base.h>
  43#include <target/target_core_fabric.h>
  44#include <target/target_core_fabric_configfs.h>
  45#include <target/target_core_configfs.h>
  46#include <target/configfs_macros.h>
  47#include <linux/vhost.h>
  48#include <linux/virtio_scsi.h>
  49#include <linux/llist.h>
  50#include <linux/bitmap.h>
  51#include <linux/percpu_ida.h>
  52
  53#include "vhost.h"
  54
  55#define TCM_VHOST_VERSION  "v0.1"
  56#define TCM_VHOST_NAMELEN 256
  57#define TCM_VHOST_MAX_CDB_SIZE 32
  58#define TCM_VHOST_DEFAULT_TAGS 256
  59#define TCM_VHOST_PREALLOC_SGLS 2048
  60#define TCM_VHOST_PREALLOC_PAGES 2048
 
  61
  62struct vhost_scsi_inflight {
  63	/* Wait for the flush operation to finish */
  64	struct completion comp;
  65	/* Refcount for the inflight reqs */
  66	struct kref kref;
  67};
  68
  69struct tcm_vhost_cmd {
  70	/* Descriptor from vhost_get_vq_desc() for virt_queue segment */
  71	int tvc_vq_desc;
  72	/* virtio-scsi initiator task attribute */
  73	int tvc_task_attr;
 
 
  74	/* virtio-scsi initiator data direction */
  75	enum dma_data_direction tvc_data_direction;
  76	/* Expected data transfer length from virtio-scsi header */
  77	u32 tvc_exp_data_len;
  78	/* The Tag from include/linux/virtio_scsi.h:struct virtio_scsi_cmd_req */
  79	u64 tvc_tag;
  80	/* The number of scatterlists associated with this cmd */
  81	u32 tvc_sgl_count;
  82	/* Saved unpacked SCSI LUN for tcm_vhost_submission_work() */
 
  83	u32 tvc_lun;
  84	/* Pointer to the SGL formatted memory from virtio-scsi */
  85	struct scatterlist *tvc_sgl;
 
  86	struct page **tvc_upages;
  87	/* Pointer to response */
  88	struct virtio_scsi_cmd_resp __user *tvc_resp;
  89	/* Pointer to vhost_scsi for our device */
  90	struct vhost_scsi *tvc_vhost;
  91	/* Pointer to vhost_virtqueue for the cmd */
  92	struct vhost_virtqueue *tvc_vq;
  93	/* Pointer to vhost nexus memory */
  94	struct tcm_vhost_nexus *tvc_nexus;
  95	/* The TCM I/O descriptor that is accessed via container_of() */
  96	struct se_cmd tvc_se_cmd;
  97	/* work item used for cmwq dispatch to tcm_vhost_submission_work() */
  98	struct work_struct work;
  99	/* Copy of the incoming SCSI command descriptor block (CDB) */
 100	unsigned char tvc_cdb[TCM_VHOST_MAX_CDB_SIZE];
 101	/* Sense buffer that will be mapped into outgoing status */
 102	unsigned char tvc_sense_buf[TRANSPORT_SENSE_BUFFER];
 103	/* Completed commands list, serviced from vhost worker thread */
 104	struct llist_node tvc_completion_list;
 105	/* Used to track inflight cmd */
 106	struct vhost_scsi_inflight *inflight;
 107};
 108
 109struct tcm_vhost_nexus {
 110	/* Pointer to TCM session for I_T Nexus */
 111	struct se_session *tvn_se_sess;
 112};
 113
 114struct tcm_vhost_nacl {
 115	/* Binary World Wide unique Port Name for Vhost Initiator port */
 116	u64 iport_wwpn;
 117	/* ASCII formatted WWPN for Sas Initiator port */
 118	char iport_name[TCM_VHOST_NAMELEN];
 119	/* Returned by tcm_vhost_make_nodeacl() */
 120	struct se_node_acl se_node_acl;
 121};
 122
 123struct tcm_vhost_tpg {
 124	/* Vhost port target portal group tag for TCM */
 125	u16 tport_tpgt;
 126	/* Used to track number of TPG Port/Lun Links wrt to explict I_T Nexus shutdown */
 127	int tv_tpg_port_count;
 128	/* Used for vhost_scsi device reference to tpg_nexus, protected by tv_tpg_mutex */
 129	int tv_tpg_vhost_count;
 130	/* list for tcm_vhost_list */
 
 
 131	struct list_head tv_tpg_list;
 132	/* Used to protect access for tpg_nexus */
 133	struct mutex tv_tpg_mutex;
 134	/* Pointer to the TCM VHost I_T Nexus for this TPG endpoint */
 135	struct tcm_vhost_nexus *tpg_nexus;
 136	/* Pointer back to tcm_vhost_tport */
 137	struct tcm_vhost_tport *tport;
 138	/* Returned by tcm_vhost_make_tpg() */
 139	struct se_portal_group se_tpg;
 140	/* Pointer back to vhost_scsi, protected by tv_tpg_mutex */
 141	struct vhost_scsi *vhost_scsi;
 142};
 143
 144struct tcm_vhost_tport {
 145	/* SCSI protocol the tport is providing */
 146	u8 tport_proto_id;
 147	/* Binary World Wide unique Port Name for Vhost Target port */
 148	u64 tport_wwpn;
 149	/* ASCII formatted WWPN for Vhost Target port */
 150	char tport_name[TCM_VHOST_NAMELEN];
 151	/* Returned by tcm_vhost_make_tport() */
 152	struct se_wwn tport_wwn;
 153};
 154
 155struct tcm_vhost_evt {
 156	/* event to be sent to guest */
 157	struct virtio_scsi_event event;
 158	/* event list, serviced from vhost worker thread */
 159	struct llist_node list;
 160};
 161
 162enum {
 163	VHOST_SCSI_VQ_CTL = 0,
 164	VHOST_SCSI_VQ_EVT = 1,
 165	VHOST_SCSI_VQ_IO = 2,
 166};
 167
 
 168enum {
 169	VHOST_SCSI_FEATURES = VHOST_FEATURES | (1ULL << VIRTIO_SCSI_F_HOTPLUG)
 
 170};
 171
 172#define VHOST_SCSI_MAX_TARGET	256
 173#define VHOST_SCSI_MAX_VQ	128
 174#define VHOST_SCSI_MAX_EVENT	128
 175
 176struct vhost_scsi_virtqueue {
 177	struct vhost_virtqueue vq;
 178	/*
 179	 * Reference counting for inflight reqs, used for flush operation. At
 180	 * each time, one reference tracks new commands submitted, while we
 181	 * wait for another one to reach 0.
 182	 */
 183	struct vhost_scsi_inflight inflights[2];
 184	/*
 185	 * Indicate current inflight in use, protected by vq->mutex.
 186	 * Writers must also take dev mutex and flush under it.
 187	 */
 188	int inflight_idx;
 189};
 190
 191struct vhost_scsi {
 192	/* Protected by vhost_scsi->dev.mutex */
 193	struct tcm_vhost_tpg **vs_tpg;
 194	char vs_vhost_wwpn[TRANSPORT_IQN_LEN];
 195
 196	struct vhost_dev dev;
 197	struct vhost_scsi_virtqueue vqs[VHOST_SCSI_MAX_VQ];
 198
 199	struct vhost_work vs_completion_work; /* cmd completion work item */
 200	struct llist_head vs_completion_list; /* cmd completion queue */
 201
 202	struct vhost_work vs_event_work; /* evt injection work item */
 203	struct llist_head vs_event_list; /* evt injection queue */
 204
 205	bool vs_events_missed; /* any missed events, protected by vq->mutex */
 206	int vs_events_nr; /* num of pending events, protected by vq->mutex */
 207};
 208
 209/* Local pointer to allocated TCM configfs fabric module */
 210static struct target_fabric_configfs *tcm_vhost_fabric_configfs;
 211
 212static struct workqueue_struct *tcm_vhost_workqueue;
 213
 214/* Global spinlock to protect tcm_vhost TPG list for vhost IOCTL access */
 215static DEFINE_MUTEX(tcm_vhost_mutex);
 216static LIST_HEAD(tcm_vhost_list);
 217
 218static int iov_num_pages(struct iovec *iov)
 219{
 220	return (PAGE_ALIGN((unsigned long)iov->iov_base + iov->iov_len) -
 221	       ((unsigned long)iov->iov_base & PAGE_MASK)) >> PAGE_SHIFT;
 222}
 223
 224static void tcm_vhost_done_inflight(struct kref *kref)
 225{
 226	struct vhost_scsi_inflight *inflight;
 227
 228	inflight = container_of(kref, struct vhost_scsi_inflight, kref);
 229	complete(&inflight->comp);
 230}
 231
 232static void tcm_vhost_init_inflight(struct vhost_scsi *vs,
 233				    struct vhost_scsi_inflight *old_inflight[])
 234{
 235	struct vhost_scsi_inflight *new_inflight;
 236	struct vhost_virtqueue *vq;
 237	int idx, i;
 238
 239	for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
 240		vq = &vs->vqs[i].vq;
 241
 242		mutex_lock(&vq->mutex);
 243
 244		/* store old infight */
 245		idx = vs->vqs[i].inflight_idx;
 246		if (old_inflight)
 247			old_inflight[i] = &vs->vqs[i].inflights[idx];
 248
 249		/* setup new infight */
 250		vs->vqs[i].inflight_idx = idx ^ 1;
 251		new_inflight = &vs->vqs[i].inflights[idx ^ 1];
 252		kref_init(&new_inflight->kref);
 253		init_completion(&new_inflight->comp);
 254
 255		mutex_unlock(&vq->mutex);
 256	}
 257}
 258
 259static struct vhost_scsi_inflight *
 260tcm_vhost_get_inflight(struct vhost_virtqueue *vq)
 261{
 262	struct vhost_scsi_inflight *inflight;
 263	struct vhost_scsi_virtqueue *svq;
 264
 265	svq = container_of(vq, struct vhost_scsi_virtqueue, vq);
 266	inflight = &svq->inflights[svq->inflight_idx];
 267	kref_get(&inflight->kref);
 268
 269	return inflight;
 270}
 271
 272static void tcm_vhost_put_inflight(struct vhost_scsi_inflight *inflight)
 273{
 274	kref_put(&inflight->kref, tcm_vhost_done_inflight);
 275}
 276
 277static int tcm_vhost_check_true(struct se_portal_group *se_tpg)
 278{
 279	return 1;
 280}
 281
 282static int tcm_vhost_check_false(struct se_portal_group *se_tpg)
 283{
 284	return 0;
 285}
 286
 287static char *tcm_vhost_get_fabric_name(void)
 288{
 289	return "vhost";
 290}
 291
 292static u8 tcm_vhost_get_fabric_proto_ident(struct se_portal_group *se_tpg)
 293{
 294	struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 295				struct tcm_vhost_tpg, se_tpg);
 296	struct tcm_vhost_tport *tport = tpg->tport;
 297
 298	switch (tport->tport_proto_id) {
 299	case SCSI_PROTOCOL_SAS:
 300		return sas_get_fabric_proto_ident(se_tpg);
 301	case SCSI_PROTOCOL_FCP:
 302		return fc_get_fabric_proto_ident(se_tpg);
 303	case SCSI_PROTOCOL_ISCSI:
 304		return iscsi_get_fabric_proto_ident(se_tpg);
 305	default:
 306		pr_err("Unknown tport_proto_id: 0x%02x, using"
 307			" SAS emulation\n", tport->tport_proto_id);
 308		break;
 309	}
 310
 311	return sas_get_fabric_proto_ident(se_tpg);
 312}
 313
 314static char *tcm_vhost_get_fabric_wwn(struct se_portal_group *se_tpg)
 315{
 316	struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 317				struct tcm_vhost_tpg, se_tpg);
 318	struct tcm_vhost_tport *tport = tpg->tport;
 319
 320	return &tport->tport_name[0];
 321}
 322
 323static u16 tcm_vhost_get_tag(struct se_portal_group *se_tpg)
 324{
 325	struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 326				struct tcm_vhost_tpg, se_tpg);
 327	return tpg->tport_tpgt;
 328}
 329
 330static u32 tcm_vhost_get_default_depth(struct se_portal_group *se_tpg)
 331{
 332	return 1;
 333}
 334
 335static u32
 336tcm_vhost_get_pr_transport_id(struct se_portal_group *se_tpg,
 337			      struct se_node_acl *se_nacl,
 338			      struct t10_pr_registration *pr_reg,
 339			      int *format_code,
 340			      unsigned char *buf)
 341{
 342	struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 343				struct tcm_vhost_tpg, se_tpg);
 344	struct tcm_vhost_tport *tport = tpg->tport;
 345
 346	switch (tport->tport_proto_id) {
 347	case SCSI_PROTOCOL_SAS:
 348		return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 349					format_code, buf);
 350	case SCSI_PROTOCOL_FCP:
 351		return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 352					format_code, buf);
 353	case SCSI_PROTOCOL_ISCSI:
 354		return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 355					format_code, buf);
 356	default:
 357		pr_err("Unknown tport_proto_id: 0x%02x, using"
 358			" SAS emulation\n", tport->tport_proto_id);
 359		break;
 360	}
 361
 362	return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 363			format_code, buf);
 364}
 365
 366static u32
 367tcm_vhost_get_pr_transport_id_len(struct se_portal_group *se_tpg,
 368				  struct se_node_acl *se_nacl,
 369				  struct t10_pr_registration *pr_reg,
 370				  int *format_code)
 371{
 372	struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 373				struct tcm_vhost_tpg, se_tpg);
 374	struct tcm_vhost_tport *tport = tpg->tport;
 375
 376	switch (tport->tport_proto_id) {
 377	case SCSI_PROTOCOL_SAS:
 378		return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 379					format_code);
 380	case SCSI_PROTOCOL_FCP:
 381		return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 382					format_code);
 383	case SCSI_PROTOCOL_ISCSI:
 384		return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 385					format_code);
 386	default:
 387		pr_err("Unknown tport_proto_id: 0x%02x, using"
 388			" SAS emulation\n", tport->tport_proto_id);
 389		break;
 390	}
 391
 392	return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 393			format_code);
 394}
 395
 396static char *
 397tcm_vhost_parse_pr_out_transport_id(struct se_portal_group *se_tpg,
 398				    const char *buf,
 399				    u32 *out_tid_len,
 400				    char **port_nexus_ptr)
 401{
 402	struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 403				struct tcm_vhost_tpg, se_tpg);
 404	struct tcm_vhost_tport *tport = tpg->tport;
 405
 406	switch (tport->tport_proto_id) {
 407	case SCSI_PROTOCOL_SAS:
 408		return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 409					port_nexus_ptr);
 410	case SCSI_PROTOCOL_FCP:
 411		return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 412					port_nexus_ptr);
 413	case SCSI_PROTOCOL_ISCSI:
 414		return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 415					port_nexus_ptr);
 416	default:
 417		pr_err("Unknown tport_proto_id: 0x%02x, using"
 418			" SAS emulation\n", tport->tport_proto_id);
 419		break;
 420	}
 421
 422	return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 423			port_nexus_ptr);
 424}
 425
 426static struct se_node_acl *
 427tcm_vhost_alloc_fabric_acl(struct se_portal_group *se_tpg)
 428{
 429	struct tcm_vhost_nacl *nacl;
 430
 431	nacl = kzalloc(sizeof(struct tcm_vhost_nacl), GFP_KERNEL);
 432	if (!nacl) {
 433		pr_err("Unable to allocate struct tcm_vhost_nacl\n");
 434		return NULL;
 435	}
 436
 437	return &nacl->se_node_acl;
 438}
 439
 440static void
 441tcm_vhost_release_fabric_acl(struct se_portal_group *se_tpg,
 442			     struct se_node_acl *se_nacl)
 443{
 444	struct tcm_vhost_nacl *nacl = container_of(se_nacl,
 445			struct tcm_vhost_nacl, se_node_acl);
 446	kfree(nacl);
 447}
 448
 449static u32 tcm_vhost_tpg_get_inst_index(struct se_portal_group *se_tpg)
 450{
 451	return 1;
 452}
 453
 454static void tcm_vhost_release_cmd(struct se_cmd *se_cmd)
 455{
 456	struct tcm_vhost_cmd *tv_cmd = container_of(se_cmd,
 457				struct tcm_vhost_cmd, tvc_se_cmd);
 458	struct se_session *se_sess = se_cmd->se_sess;
 
 459
 460	if (tv_cmd->tvc_sgl_count) {
 461		u32 i;
 462		for (i = 0; i < tv_cmd->tvc_sgl_count; i++)
 463			put_page(sg_page(&tv_cmd->tvc_sgl[i]));
 464	}
 
 
 
 
 465
 466	tcm_vhost_put_inflight(tv_cmd->inflight);
 467	percpu_ida_free(&se_sess->sess_tag_pool, se_cmd->map_tag);
 468}
 469
 470static int tcm_vhost_shutdown_session(struct se_session *se_sess)
 471{
 472	return 0;
 473}
 474
 475static void tcm_vhost_close_session(struct se_session *se_sess)
 476{
 477	return;
 478}
 479
 480static u32 tcm_vhost_sess_get_index(struct se_session *se_sess)
 481{
 482	return 0;
 483}
 484
 485static int tcm_vhost_write_pending(struct se_cmd *se_cmd)
 486{
 487	/* Go ahead and process the write immediately */
 488	target_execute_cmd(se_cmd);
 489	return 0;
 490}
 491
 492static int tcm_vhost_write_pending_status(struct se_cmd *se_cmd)
 493{
 494	return 0;
 495}
 496
 497static void tcm_vhost_set_default_node_attrs(struct se_node_acl *nacl)
 498{
 499	return;
 500}
 501
 502static u32 tcm_vhost_get_task_tag(struct se_cmd *se_cmd)
 503{
 504	return 0;
 505}
 506
 507static int tcm_vhost_get_cmd_state(struct se_cmd *se_cmd)
 508{
 509	return 0;
 510}
 511
 512static void vhost_scsi_complete_cmd(struct tcm_vhost_cmd *cmd)
 513{
 514	struct vhost_scsi *vs = cmd->tvc_vhost;
 515
 516	llist_add(&cmd->tvc_completion_list, &vs->vs_completion_list);
 517
 518	vhost_work_queue(&vs->dev, &vs->vs_completion_work);
 519}
 520
 521static int tcm_vhost_queue_data_in(struct se_cmd *se_cmd)
 522{
 523	struct tcm_vhost_cmd *cmd = container_of(se_cmd,
 524				struct tcm_vhost_cmd, tvc_se_cmd);
 525	vhost_scsi_complete_cmd(cmd);
 526	return 0;
 527}
 528
 529static int tcm_vhost_queue_status(struct se_cmd *se_cmd)
 530{
 531	struct tcm_vhost_cmd *cmd = container_of(se_cmd,
 532				struct tcm_vhost_cmd, tvc_se_cmd);
 533	vhost_scsi_complete_cmd(cmd);
 534	return 0;
 535}
 536
 537static void tcm_vhost_queue_tm_rsp(struct se_cmd *se_cmd)
 538{
 539	return;
 540}
 541
 542static void tcm_vhost_aborted_task(struct se_cmd *se_cmd)
 543{
 544	return;
 545}
 546
 547static void tcm_vhost_free_evt(struct vhost_scsi *vs, struct tcm_vhost_evt *evt)
 548{
 549	vs->vs_events_nr--;
 550	kfree(evt);
 551}
 552
 553static struct tcm_vhost_evt *
 554tcm_vhost_allocate_evt(struct vhost_scsi *vs,
 555		       u32 event, u32 reason)
 556{
 557	struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 558	struct tcm_vhost_evt *evt;
 559
 560	if (vs->vs_events_nr > VHOST_SCSI_MAX_EVENT) {
 561		vs->vs_events_missed = true;
 562		return NULL;
 563	}
 564
 565	evt = kzalloc(sizeof(*evt), GFP_KERNEL);
 566	if (!evt) {
 567		vq_err(vq, "Failed to allocate tcm_vhost_evt\n");
 568		vs->vs_events_missed = true;
 569		return NULL;
 570	}
 571
 572	evt->event.event = event;
 573	evt->event.reason = reason;
 574	vs->vs_events_nr++;
 575
 576	return evt;
 577}
 578
 579static void vhost_scsi_free_cmd(struct tcm_vhost_cmd *cmd)
 580{
 581	struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
 582
 583	/* TODO locking against target/backend threads? */
 584	transport_generic_free_cmd(se_cmd, 0);
 585
 586}
 587
 588static int vhost_scsi_check_stop_free(struct se_cmd *se_cmd)
 589{
 590	return target_put_sess_cmd(se_cmd->se_sess, se_cmd);
 591}
 592
 593static void
 594tcm_vhost_do_evt_work(struct vhost_scsi *vs, struct tcm_vhost_evt *evt)
 595{
 596	struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 597	struct virtio_scsi_event *event = &evt->event;
 598	struct virtio_scsi_event __user *eventp;
 599	unsigned out, in;
 600	int head, ret;
 601
 602	if (!vq->private_data) {
 603		vs->vs_events_missed = true;
 604		return;
 605	}
 606
 607again:
 608	vhost_disable_notify(&vs->dev, vq);
 609	head = vhost_get_vq_desc(&vs->dev, vq, vq->iov,
 610			ARRAY_SIZE(vq->iov), &out, &in,
 611			NULL, NULL);
 612	if (head < 0) {
 613		vs->vs_events_missed = true;
 614		return;
 615	}
 616	if (head == vq->num) {
 617		if (vhost_enable_notify(&vs->dev, vq))
 618			goto again;
 619		vs->vs_events_missed = true;
 620		return;
 621	}
 622
 623	if ((vq->iov[out].iov_len != sizeof(struct virtio_scsi_event))) {
 624		vq_err(vq, "Expecting virtio_scsi_event, got %zu bytes\n",
 625				vq->iov[out].iov_len);
 626		vs->vs_events_missed = true;
 627		return;
 628	}
 629
 630	if (vs->vs_events_missed) {
 631		event->event |= VIRTIO_SCSI_T_EVENTS_MISSED;
 632		vs->vs_events_missed = false;
 633	}
 634
 635	eventp = vq->iov[out].iov_base;
 636	ret = __copy_to_user(eventp, event, sizeof(*event));
 637	if (!ret)
 638		vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 639	else
 640		vq_err(vq, "Faulted on tcm_vhost_send_event\n");
 641}
 642
 643static void tcm_vhost_evt_work(struct vhost_work *work)
 644{
 645	struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 646					vs_event_work);
 647	struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 648	struct tcm_vhost_evt *evt;
 649	struct llist_node *llnode;
 650
 651	mutex_lock(&vq->mutex);
 652	llnode = llist_del_all(&vs->vs_event_list);
 653	while (llnode) {
 654		evt = llist_entry(llnode, struct tcm_vhost_evt, list);
 655		llnode = llist_next(llnode);
 656		tcm_vhost_do_evt_work(vs, evt);
 657		tcm_vhost_free_evt(vs, evt);
 658	}
 659	mutex_unlock(&vq->mutex);
 660}
 661
 662/* Fill in status and signal that we are done processing this command
 663 *
 664 * This is scheduled in the vhost work queue so we are called with the owner
 665 * process mm and can access the vring.
 666 */
 667static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
 668{
 669	struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 670					vs_completion_work);
 671	DECLARE_BITMAP(signal, VHOST_SCSI_MAX_VQ);
 672	struct virtio_scsi_cmd_resp v_rsp;
 673	struct tcm_vhost_cmd *cmd;
 674	struct llist_node *llnode;
 675	struct se_cmd *se_cmd;
 
 676	int ret, vq;
 677
 678	bitmap_zero(signal, VHOST_SCSI_MAX_VQ);
 679	llnode = llist_del_all(&vs->vs_completion_list);
 680	while (llnode) {
 681		cmd = llist_entry(llnode, struct tcm_vhost_cmd,
 682				     tvc_completion_list);
 683		llnode = llist_next(llnode);
 684		se_cmd = &cmd->tvc_se_cmd;
 685
 686		pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__,
 687			cmd, se_cmd->residual_count, se_cmd->scsi_status);
 688
 689		memset(&v_rsp, 0, sizeof(v_rsp));
 690		v_rsp.resid = se_cmd->residual_count;
 691		/* TODO is status_qualifier field needed? */
 692		v_rsp.status = se_cmd->scsi_status;
 693		v_rsp.sense_len = se_cmd->scsi_sense_length;
 
 694		memcpy(v_rsp.sense, cmd->tvc_sense_buf,
 695		       v_rsp.sense_len);
 696		ret = copy_to_user(cmd->tvc_resp, &v_rsp, sizeof(v_rsp));
 697		if (likely(ret == 0)) {
 
 
 
 698			struct vhost_scsi_virtqueue *q;
 699			vhost_add_used(cmd->tvc_vq, cmd->tvc_vq_desc, 0);
 700			q = container_of(cmd->tvc_vq, struct vhost_scsi_virtqueue, vq);
 701			vq = q - vs->vqs;
 702			__set_bit(vq, signal);
 703		} else
 704			pr_err("Faulted on virtio_scsi_cmd_resp\n");
 705
 706		vhost_scsi_free_cmd(cmd);
 707	}
 708
 709	vq = -1;
 710	while ((vq = find_next_bit(signal, VHOST_SCSI_MAX_VQ, vq + 1))
 711		< VHOST_SCSI_MAX_VQ)
 712		vhost_signal(&vs->dev, &vs->vqs[vq].vq);
 713}
 714
 715static struct tcm_vhost_cmd *
 716vhost_scsi_get_tag(struct vhost_virtqueue *vq,
 717			struct tcm_vhost_tpg *tpg,
 718			struct virtio_scsi_cmd_req *v_req,
 719			u32 exp_data_len,
 720			int data_direction)
 721{
 722	struct tcm_vhost_cmd *cmd;
 723	struct tcm_vhost_nexus *tv_nexus;
 724	struct se_session *se_sess;
 725	struct scatterlist *sg;
 726	struct page **pages;
 727	int tag;
 728
 729	tv_nexus = tpg->tpg_nexus;
 730	if (!tv_nexus) {
 731		pr_err("Unable to locate active struct tcm_vhost_nexus\n");
 732		return ERR_PTR(-EIO);
 733	}
 734	se_sess = tv_nexus->tvn_se_sess;
 735
 736	tag = percpu_ida_alloc(&se_sess->sess_tag_pool, TASK_RUNNING);
 737	if (tag < 0) {
 738		pr_err("Unable to obtain tag for tcm_vhost_cmd\n");
 739		return ERR_PTR(-ENOMEM);
 740	}
 741
 742	cmd = &((struct tcm_vhost_cmd *)se_sess->sess_cmd_map)[tag];
 743	sg = cmd->tvc_sgl;
 
 744	pages = cmd->tvc_upages;
 745	memset(cmd, 0, sizeof(struct tcm_vhost_cmd));
 746
 747	cmd->tvc_sgl = sg;
 
 748	cmd->tvc_upages = pages;
 749	cmd->tvc_se_cmd.map_tag = tag;
 750	cmd->tvc_tag = v_req->tag;
 751	cmd->tvc_task_attr = v_req->task_attr;
 
 752	cmd->tvc_exp_data_len = exp_data_len;
 753	cmd->tvc_data_direction = data_direction;
 754	cmd->tvc_nexus = tv_nexus;
 755	cmd->inflight = tcm_vhost_get_inflight(vq);
 
 
 756
 757	return cmd;
 758}
 759
 760/*
 761 * Map a user memory range into a scatterlist
 762 *
 763 * Returns the number of scatterlist entries used or -errno on error.
 764 */
 765static int
 766vhost_scsi_map_to_sgl(struct tcm_vhost_cmd *tv_cmd,
 
 
 767		      struct scatterlist *sgl,
 768		      unsigned int sgl_count,
 769		      struct iovec *iov,
 770		      int write)
 771{
 772	unsigned int npages = 0, pages_nr, offset, nbytes;
 
 773	struct scatterlist *sg = sgl;
 774	void __user *ptr = iov->iov_base;
 775	size_t len = iov->iov_len;
 776	struct page **pages;
 777	int ret, i;
 778
 779	if (sgl_count > TCM_VHOST_PREALLOC_SGLS) {
 780		pr_err("vhost_scsi_map_to_sgl() psgl_count: %u greater than"
 781		       " preallocated TCM_VHOST_PREALLOC_SGLS: %u\n",
 782			sgl_count, TCM_VHOST_PREALLOC_SGLS);
 783		return -ENOBUFS;
 784	}
 785
 786	pages_nr = iov_num_pages(iov);
 787	if (pages_nr > sgl_count)
 788		return -ENOBUFS;
 789
 790	if (pages_nr > TCM_VHOST_PREALLOC_PAGES) {
 791		pr_err("vhost_scsi_map_to_sgl() pages_nr: %u greater than"
 792		       " preallocated TCM_VHOST_PREALLOC_PAGES: %u\n",
 793			pages_nr, TCM_VHOST_PREALLOC_PAGES);
 794		return -ENOBUFS;
 795	}
 796
 797	pages = tv_cmd->tvc_upages;
 798
 799	ret = get_user_pages_fast((unsigned long)ptr, pages_nr, write, pages);
 800	/* No pages were pinned */
 801	if (ret < 0)
 802		goto out;
 803	/* Less pages pinned than wanted */
 804	if (ret != pages_nr) {
 805		for (i = 0; i < ret; i++)
 806			put_page(pages[i]);
 807		ret = -EFAULT;
 808		goto out;
 809	}
 810
 811	while (len > 0) {
 812		offset = (uintptr_t)ptr & ~PAGE_MASK;
 813		nbytes = min_t(unsigned int, PAGE_SIZE - offset, len);
 814		sg_set_page(sg, pages[npages], nbytes, offset);
 815		ptr += nbytes;
 816		len -= nbytes;
 817		sg++;
 818		npages++;
 819	}
 820
 821out:
 822	return ret;
 823}
 824
 825static int
 826vhost_scsi_map_iov_to_sgl(struct tcm_vhost_cmd *cmd,
 827			  struct iovec *iov,
 828			  unsigned int niov,
 829			  int write)
 830{
 831	int ret;
 832	unsigned int i;
 833	u32 sgl_count;
 834	struct scatterlist *sg;
 835
 836	/*
 837	 * Find out how long sglist needs to be
 838	 */
 839	sgl_count = 0;
 840	for (i = 0; i < niov; i++)
 841		sgl_count += iov_num_pages(&iov[i]);
 842
 843	/* TODO overflow checking */
 
 
 
 
 844
 845	sg = cmd->tvc_sgl;
 846	pr_debug("%s sg %p sgl_count %u\n", __func__, sg, sgl_count);
 847	sg_init_table(sg, sgl_count);
 
 
 
 
 
 848
 849	cmd->tvc_sgl_count = sgl_count;
 
 
 
 
 
 
 
 
 
 
 850
 851	pr_debug("Mapping %u iovecs for %u pages\n", niov, sgl_count);
 852	for (i = 0; i < niov; i++) {
 853		ret = vhost_scsi_map_to_sgl(cmd, sg, sgl_count, &iov[i],
 854					    write);
 855		if (ret < 0) {
 856			for (i = 0; i < cmd->tvc_sgl_count; i++)
 857				put_page(sg_page(&cmd->tvc_sgl[i]));
 
 
 
 
 
 
 
 
 
 
 858
 859			cmd->tvc_sgl_count = 0;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 860			return ret;
 861		}
 
 
 
 
 
 862
 863		sg += ret;
 864		sgl_count -= ret;
 
 
 
 
 
 
 
 
 865	}
 866	return 0;
 867}
 868
 869static void tcm_vhost_submission_work(struct work_struct *work)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 870{
 871	struct tcm_vhost_cmd *cmd =
 872		container_of(work, struct tcm_vhost_cmd, work);
 873	struct tcm_vhost_nexus *tv_nexus;
 874	struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
 875	struct scatterlist *sg_ptr, *sg_bidi_ptr = NULL;
 876	int rc, sg_no_bidi = 0;
 877
 
 878	if (cmd->tvc_sgl_count) {
 879		sg_ptr = cmd->tvc_sgl;
 880/* FIXME: Fix BIDI operation in tcm_vhost_submission_work() */
 881#if 0
 882		if (se_cmd->se_cmd_flags & SCF_BIDI) {
 883			sg_bidi_ptr = NULL;
 884			sg_no_bidi = 0;
 885		}
 886#endif
 887	} else {
 888		sg_ptr = NULL;
 889	}
 890	tv_nexus = cmd->tvc_nexus;
 891
 
 892	rc = target_submit_cmd_map_sgls(se_cmd, tv_nexus->tvn_se_sess,
 893			cmd->tvc_cdb, &cmd->tvc_sense_buf[0],
 894			cmd->tvc_lun, cmd->tvc_exp_data_len,
 895			cmd->tvc_task_attr, cmd->tvc_data_direction,
 896			TARGET_SCF_ACK_KREF, sg_ptr, cmd->tvc_sgl_count,
 897			sg_bidi_ptr, sg_no_bidi, NULL, 0);
 
 898	if (rc < 0) {
 899		transport_send_check_condition_and_sense(se_cmd,
 900				TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
 901		transport_generic_free_cmd(se_cmd, 0);
 902	}
 903}
 904
 905static void
 906vhost_scsi_send_bad_target(struct vhost_scsi *vs,
 907			   struct vhost_virtqueue *vq,
 908			   int head, unsigned out)
 909{
 910	struct virtio_scsi_cmd_resp __user *resp;
 911	struct virtio_scsi_cmd_resp rsp;
 912	int ret;
 913
 914	memset(&rsp, 0, sizeof(rsp));
 915	rsp.response = VIRTIO_SCSI_S_BAD_TARGET;
 916	resp = vq->iov[out].iov_base;
 917	ret = __copy_to_user(resp, &rsp, sizeof(rsp));
 918	if (!ret)
 919		vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 920	else
 921		pr_err("Faulted on virtio_scsi_cmd_resp\n");
 922}
 923
 924static void
 925vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
 926{
 927	struct tcm_vhost_tpg **vs_tpg;
 928	struct virtio_scsi_cmd_req v_req;
 929	struct tcm_vhost_tpg *tpg;
 930	struct tcm_vhost_cmd *cmd;
 931	u32 exp_data_len, data_first, data_num, data_direction;
 932	unsigned out, in, i;
 933	int head, ret;
 934	u8 target;
 
 
 
 
 
 
 
 935
 936	mutex_lock(&vq->mutex);
 937	/*
 938	 * We can handle the vq only after the endpoint is setup by calling the
 939	 * VHOST_SCSI_SET_ENDPOINT ioctl.
 940	 */
 941	vs_tpg = vq->private_data;
 942	if (!vs_tpg)
 943		goto out;
 944
 945	vhost_disable_notify(&vs->dev, vq);
 946
 947	for (;;) {
 948		head = vhost_get_vq_desc(&vs->dev, vq, vq->iov,
 949					ARRAY_SIZE(vq->iov), &out, &in,
 950					NULL, NULL);
 951		pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n",
 952					head, out, in);
 953		/* On error, stop handling until the next kick. */
 954		if (unlikely(head < 0))
 955			break;
 956		/* Nothing new?  Wait for eventfd to tell us they refilled. */
 957		if (head == vq->num) {
 958			if (unlikely(vhost_enable_notify(&vs->dev, vq))) {
 959				vhost_disable_notify(&vs->dev, vq);
 960				continue;
 961			}
 962			break;
 963		}
 964
 965/* FIXME: BIDI operation */
 966		if (out == 1 && in == 1) {
 967			data_direction = DMA_NONE;
 968			data_first = 0;
 969			data_num = 0;
 970		} else if (out == 1 && in > 1) {
 971			data_direction = DMA_FROM_DEVICE;
 972			data_first = out + 1;
 973			data_num = in - 1;
 974		} else if (out > 1 && in == 1) {
 975			data_direction = DMA_TO_DEVICE;
 976			data_first = 1;
 977			data_num = out - 1;
 978		} else {
 979			vq_err(vq, "Invalid buffer layout out: %u in: %u\n",
 980					out, in);
 981			break;
 982		}
 983
 984		/*
 985		 * Check for a sane resp buffer so we can report errors to
 986		 * the guest.
 987		 */
 988		if (unlikely(vq->iov[out].iov_len !=
 989					sizeof(struct virtio_scsi_cmd_resp))) {
 990			vq_err(vq, "Expecting virtio_scsi_cmd_resp, got %zu"
 991				" bytes\n", vq->iov[out].iov_len);
 992			break;
 
 
 
 
 
 993		}
 
 
 
 
 
 994
 995		if (unlikely(vq->iov[0].iov_len != sizeof(v_req))) {
 996			vq_err(vq, "Expecting virtio_scsi_cmd_req, got %zu"
 997				" bytes\n", vq->iov[0].iov_len);
 998			break;
 999		}
1000		pr_debug("Calling __copy_from_user: vq->iov[0].iov_base: %p,"
1001			" len: %zu\n", vq->iov[0].iov_base, sizeof(v_req));
1002		ret = __copy_from_user(&v_req, vq->iov[0].iov_base,
1003				sizeof(v_req));
1004		if (unlikely(ret)) {
1005			vq_err(vq, "Faulted on virtio_scsi_cmd_req\n");
1006			break;
1007		}
1008
 
 
 
 
 
1009		/* virtio-scsi spec requires byte 0 of the lun to be 1 */
1010		if (unlikely(v_req.lun[0] != 1)) {
 
1011			vhost_scsi_send_bad_target(vs, vq, head, out);
1012			continue;
1013		}
1014
1015		/* Extract the tpgt */
1016		target = v_req.lun[1];
1017		tpg = ACCESS_ONCE(vs_tpg[target]);
1018
1019		/* Target does not exist, fail the request */
1020		if (unlikely(!tpg)) {
 
1021			vhost_scsi_send_bad_target(vs, vq, head, out);
1022			continue;
1023		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1024
1025		exp_data_len = 0;
1026		for (i = 0; i < data_num; i++)
1027			exp_data_len += vq->iov[data_first + i].iov_len;
 
 
 
 
1028
1029		cmd = vhost_scsi_get_tag(vq, tpg, &v_req,
1030					 exp_data_len, data_direction);
1031		if (IS_ERR(cmd)) {
1032			vq_err(vq, "vhost_scsi_get_tag failed %ld\n",
1033					PTR_ERR(cmd));
1034			goto err_cmd;
 
1035		}
1036		pr_debug("Allocated tv_cmd: %p exp_data_len: %d, data_direction"
1037			": %d\n", cmd, exp_data_len, data_direction);
1038
1039		cmd->tvc_vhost = vs;
1040		cmd->tvc_vq = vq;
1041		cmd->tvc_resp = vq->iov[out].iov_base;
1042
1043		/*
1044		 * Copy in the recieved CDB descriptor into cmd->tvc_cdb
1045		 * that will be used by tcm_vhost_new_cmd_map() and down into
1046		 * target_setup_cmd_from_cdb()
1047		 */
1048		memcpy(cmd->tvc_cdb, v_req.cdb, TCM_VHOST_MAX_CDB_SIZE);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1049		/*
1050		 * Check that the recieved CDB size does not exceeded our
1051		 * hardcoded max for tcm_vhost
 
 
 
1052		 */
1053		/* TODO what if cdb was too small for varlen cdb header? */
1054		if (unlikely(scsi_command_size(cmd->tvc_cdb) >
1055					TCM_VHOST_MAX_CDB_SIZE)) {
1056			vq_err(vq, "Received SCSI CDB with command_size: %d that"
1057				" exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1058				scsi_command_size(cmd->tvc_cdb),
1059				TCM_VHOST_MAX_CDB_SIZE);
1060			goto err_free;
 
 
 
 
 
 
 
 
 
1061		}
1062		cmd->tvc_lun = ((v_req.lun[2] << 8) | v_req.lun[3]) & 0x3FFF;
 
 
 
1063
1064		pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n",
1065			cmd->tvc_cdb[0], cmd->tvc_lun);
 
 
1066
1067		if (data_direction != DMA_NONE) {
1068			ret = vhost_scsi_map_iov_to_sgl(cmd,
1069					&vq->iov[data_first], data_num,
1070					data_direction == DMA_FROM_DEVICE);
1071			if (unlikely(ret)) {
1072				vq_err(vq, "Failed to map iov to sgl\n");
1073				goto err_free;
 
 
1074			}
1075		}
1076
1077		/*
1078		 * Save the descriptor from vhost_get_vq_desc() to be used to
1079		 * complete the virtio-scsi request in TCM callback context via
1080		 * tcm_vhost_queue_data_in() and tcm_vhost_queue_status()
1081		 */
1082		cmd->tvc_vq_desc = head;
1083		/*
1084		 * Dispatch tv_cmd descriptor for cmwq execution in process
1085		 * context provided by tcm_vhost_workqueue.  This also ensures
1086		 * tv_cmd is executed on the same kworker CPU as this vhost
1087		 * thread to gain positive L2 cache locality effects..
1088		 */
1089		INIT_WORK(&cmd->work, tcm_vhost_submission_work);
1090		queue_work(tcm_vhost_workqueue, &cmd->work);
1091	}
1092
1093	mutex_unlock(&vq->mutex);
1094	return;
1095
1096err_free:
1097	vhost_scsi_free_cmd(cmd);
1098err_cmd:
1099	vhost_scsi_send_bad_target(vs, vq, head, out);
1100out:
1101	mutex_unlock(&vq->mutex);
1102}
1103
1104static void vhost_scsi_ctl_handle_kick(struct vhost_work *work)
1105{
1106	pr_debug("%s: The handling func for control queue.\n", __func__);
1107}
1108
1109static void
1110tcm_vhost_send_evt(struct vhost_scsi *vs,
1111		   struct tcm_vhost_tpg *tpg,
1112		   struct se_lun *lun,
1113		   u32 event,
1114		   u32 reason)
1115{
1116	struct tcm_vhost_evt *evt;
1117
1118	evt = tcm_vhost_allocate_evt(vs, event, reason);
1119	if (!evt)
1120		return;
1121
1122	if (tpg && lun) {
1123		/* TODO: share lun setup code with virtio-scsi.ko */
1124		/*
1125		 * Note: evt->event is zeroed when we allocate it and
1126		 * lun[4-7] need to be zero according to virtio-scsi spec.
1127		 */
1128		evt->event.lun[0] = 0x01;
1129		evt->event.lun[1] = tpg->tport_tpgt & 0xFF;
1130		if (lun->unpacked_lun >= 256)
1131			evt->event.lun[2] = lun->unpacked_lun >> 8 | 0x40 ;
1132		evt->event.lun[3] = lun->unpacked_lun & 0xFF;
1133	}
1134
1135	llist_add(&evt->list, &vs->vs_event_list);
1136	vhost_work_queue(&vs->dev, &vs->vs_event_work);
1137}
1138
1139static void vhost_scsi_evt_handle_kick(struct vhost_work *work)
1140{
1141	struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1142						poll.work);
1143	struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1144
1145	mutex_lock(&vq->mutex);
1146	if (!vq->private_data)
1147		goto out;
1148
1149	if (vs->vs_events_missed)
1150		tcm_vhost_send_evt(vs, NULL, NULL, VIRTIO_SCSI_T_NO_EVENT, 0);
1151out:
1152	mutex_unlock(&vq->mutex);
1153}
1154
1155static void vhost_scsi_handle_kick(struct vhost_work *work)
1156{
1157	struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1158						poll.work);
1159	struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1160
1161	vhost_scsi_handle_vq(vs, vq);
1162}
1163
1164static void vhost_scsi_flush_vq(struct vhost_scsi *vs, int index)
1165{
1166	vhost_poll_flush(&vs->vqs[index].vq.poll);
1167}
1168
1169/* Callers must hold dev mutex */
1170static void vhost_scsi_flush(struct vhost_scsi *vs)
1171{
1172	struct vhost_scsi_inflight *old_inflight[VHOST_SCSI_MAX_VQ];
1173	int i;
1174
1175	/* Init new inflight and remember the old inflight */
1176	tcm_vhost_init_inflight(vs, old_inflight);
1177
1178	/*
1179	 * The inflight->kref was initialized to 1. We decrement it here to
1180	 * indicate the start of the flush operation so that it will reach 0
1181	 * when all the reqs are finished.
1182	 */
1183	for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1184		kref_put(&old_inflight[i]->kref, tcm_vhost_done_inflight);
1185
1186	/* Flush both the vhost poll and vhost work */
1187	for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1188		vhost_scsi_flush_vq(vs, i);
1189	vhost_work_flush(&vs->dev, &vs->vs_completion_work);
1190	vhost_work_flush(&vs->dev, &vs->vs_event_work);
1191
1192	/* Wait for all reqs issued before the flush to be finished */
1193	for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1194		wait_for_completion(&old_inflight[i]->comp);
1195}
1196
1197/*
1198 * Called from vhost_scsi_ioctl() context to walk the list of available
1199 * tcm_vhost_tpg with an active struct tcm_vhost_nexus
1200 *
1201 *  The lock nesting rule is:
1202 *    tcm_vhost_mutex -> vs->dev.mutex -> tpg->tv_tpg_mutex -> vq->mutex
1203 */
1204static int
1205vhost_scsi_set_endpoint(struct vhost_scsi *vs,
1206			struct vhost_scsi_target *t)
1207{
1208	struct tcm_vhost_tport *tv_tport;
1209	struct tcm_vhost_tpg *tpg;
1210	struct tcm_vhost_tpg **vs_tpg;
 
1211	struct vhost_virtqueue *vq;
1212	int index, ret, i, len;
1213	bool match = false;
1214
1215	mutex_lock(&tcm_vhost_mutex);
1216	mutex_lock(&vs->dev.mutex);
1217
1218	/* Verify that ring has been setup correctly. */
1219	for (index = 0; index < vs->dev.nvqs; ++index) {
1220		/* Verify that ring has been setup correctly. */
1221		if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1222			ret = -EFAULT;
1223			goto out;
1224		}
1225	}
1226
1227	len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET;
1228	vs_tpg = kzalloc(len, GFP_KERNEL);
1229	if (!vs_tpg) {
1230		ret = -ENOMEM;
1231		goto out;
1232	}
1233	if (vs->vs_tpg)
1234		memcpy(vs_tpg, vs->vs_tpg, len);
1235
1236	list_for_each_entry(tpg, &tcm_vhost_list, tv_tpg_list) {
1237		mutex_lock(&tpg->tv_tpg_mutex);
1238		if (!tpg->tpg_nexus) {
1239			mutex_unlock(&tpg->tv_tpg_mutex);
1240			continue;
1241		}
1242		if (tpg->tv_tpg_vhost_count != 0) {
1243			mutex_unlock(&tpg->tv_tpg_mutex);
1244			continue;
1245		}
1246		tv_tport = tpg->tport;
1247
1248		if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1249			if (vs->vs_tpg && vs->vs_tpg[tpg->tport_tpgt]) {
1250				kfree(vs_tpg);
1251				mutex_unlock(&tpg->tv_tpg_mutex);
1252				ret = -EEXIST;
1253				goto out;
1254			}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1255			tpg->tv_tpg_vhost_count++;
1256			tpg->vhost_scsi = vs;
1257			vs_tpg[tpg->tport_tpgt] = tpg;
1258			smp_mb__after_atomic_inc();
1259			match = true;
1260		}
1261		mutex_unlock(&tpg->tv_tpg_mutex);
1262	}
1263
1264	if (match) {
1265		memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
1266		       sizeof(vs->vs_vhost_wwpn));
1267		for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1268			vq = &vs->vqs[i].vq;
1269			mutex_lock(&vq->mutex);
1270			vq->private_data = vs_tpg;
1271			vhost_init_used(vq);
1272			mutex_unlock(&vq->mutex);
1273		}
1274		ret = 0;
1275	} else {
1276		ret = -EEXIST;
1277	}
1278
1279	/*
1280	 * Act as synchronize_rcu to make sure access to
1281	 * old vs->vs_tpg is finished.
1282	 */
1283	vhost_scsi_flush(vs);
1284	kfree(vs->vs_tpg);
1285	vs->vs_tpg = vs_tpg;
1286
1287out:
1288	mutex_unlock(&vs->dev.mutex);
1289	mutex_unlock(&tcm_vhost_mutex);
1290	return ret;
1291}
1292
1293static int
1294vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
1295			  struct vhost_scsi_target *t)
1296{
1297	struct tcm_vhost_tport *tv_tport;
1298	struct tcm_vhost_tpg *tpg;
 
1299	struct vhost_virtqueue *vq;
1300	bool match = false;
1301	int index, ret, i;
1302	u8 target;
1303
1304	mutex_lock(&tcm_vhost_mutex);
1305	mutex_lock(&vs->dev.mutex);
1306	/* Verify that ring has been setup correctly. */
1307	for (index = 0; index < vs->dev.nvqs; ++index) {
1308		if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1309			ret = -EFAULT;
1310			goto err_dev;
1311		}
1312	}
1313
1314	if (!vs->vs_tpg) {
1315		ret = 0;
1316		goto err_dev;
1317	}
1318
1319	for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1320		target = i;
1321		tpg = vs->vs_tpg[target];
1322		if (!tpg)
1323			continue;
1324
1325		mutex_lock(&tpg->tv_tpg_mutex);
1326		tv_tport = tpg->tport;
1327		if (!tv_tport) {
1328			ret = -ENODEV;
1329			goto err_tpg;
1330		}
1331
1332		if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1333			pr_warn("tv_tport->tport_name: %s, tpg->tport_tpgt: %hu"
1334				" does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
1335				tv_tport->tport_name, tpg->tport_tpgt,
1336				t->vhost_wwpn, t->vhost_tpgt);
1337			ret = -EINVAL;
1338			goto err_tpg;
1339		}
1340		tpg->tv_tpg_vhost_count--;
1341		tpg->vhost_scsi = NULL;
1342		vs->vs_tpg[target] = NULL;
1343		match = true;
1344		mutex_unlock(&tpg->tv_tpg_mutex);
 
 
 
 
 
 
1345	}
1346	if (match) {
1347		for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1348			vq = &vs->vqs[i].vq;
1349			mutex_lock(&vq->mutex);
1350			vq->private_data = NULL;
1351			mutex_unlock(&vq->mutex);
1352		}
1353	}
1354	/*
1355	 * Act as synchronize_rcu to make sure access to
1356	 * old vs->vs_tpg is finished.
1357	 */
1358	vhost_scsi_flush(vs);
1359	kfree(vs->vs_tpg);
1360	vs->vs_tpg = NULL;
1361	WARN_ON(vs->vs_events_nr);
1362	mutex_unlock(&vs->dev.mutex);
1363	mutex_unlock(&tcm_vhost_mutex);
1364	return 0;
1365
1366err_tpg:
1367	mutex_unlock(&tpg->tv_tpg_mutex);
1368err_dev:
1369	mutex_unlock(&vs->dev.mutex);
1370	mutex_unlock(&tcm_vhost_mutex);
1371	return ret;
1372}
1373
1374static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features)
1375{
 
 
 
1376	if (features & ~VHOST_SCSI_FEATURES)
1377		return -EOPNOTSUPP;
1378
1379	mutex_lock(&vs->dev.mutex);
1380	if ((features & (1 << VHOST_F_LOG_ALL)) &&
1381	    !vhost_log_access_ok(&vs->dev)) {
1382		mutex_unlock(&vs->dev.mutex);
1383		return -EFAULT;
1384	}
1385	vs->dev.acked_features = features;
1386	smp_wmb();
1387	vhost_scsi_flush(vs);
 
 
 
 
1388	mutex_unlock(&vs->dev.mutex);
1389	return 0;
1390}
1391
1392static void vhost_scsi_free(struct vhost_scsi *vs)
1393{
1394	if (is_vmalloc_addr(vs))
1395		vfree(vs);
1396	else
1397		kfree(vs);
1398}
1399
1400static int vhost_scsi_open(struct inode *inode, struct file *f)
1401{
1402	struct vhost_scsi *vs;
1403	struct vhost_virtqueue **vqs;
1404	int r = -ENOMEM, i;
1405
1406	vs = kzalloc(sizeof(*vs), GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
1407	if (!vs) {
1408		vs = vzalloc(sizeof(*vs));
1409		if (!vs)
1410			goto err_vs;
1411	}
1412
1413	vqs = kmalloc(VHOST_SCSI_MAX_VQ * sizeof(*vqs), GFP_KERNEL);
1414	if (!vqs)
1415		goto err_vqs;
1416
1417	vhost_work_init(&vs->vs_completion_work, vhost_scsi_complete_cmd_work);
1418	vhost_work_init(&vs->vs_event_work, tcm_vhost_evt_work);
1419
1420	vs->vs_events_nr = 0;
1421	vs->vs_events_missed = false;
1422
1423	vqs[VHOST_SCSI_VQ_CTL] = &vs->vqs[VHOST_SCSI_VQ_CTL].vq;
1424	vqs[VHOST_SCSI_VQ_EVT] = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1425	vs->vqs[VHOST_SCSI_VQ_CTL].vq.handle_kick = vhost_scsi_ctl_handle_kick;
1426	vs->vqs[VHOST_SCSI_VQ_EVT].vq.handle_kick = vhost_scsi_evt_handle_kick;
1427	for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++) {
1428		vqs[i] = &vs->vqs[i].vq;
1429		vs->vqs[i].vq.handle_kick = vhost_scsi_handle_kick;
1430	}
1431	vhost_dev_init(&vs->dev, vqs, VHOST_SCSI_MAX_VQ);
1432
1433	tcm_vhost_init_inflight(vs, NULL);
1434
1435	f->private_data = vs;
1436	return 0;
1437
1438err_vqs:
1439	vhost_scsi_free(vs);
1440err_vs:
1441	return r;
1442}
1443
1444static int vhost_scsi_release(struct inode *inode, struct file *f)
1445{
1446	struct vhost_scsi *vs = f->private_data;
1447	struct vhost_scsi_target t;
1448
1449	mutex_lock(&vs->dev.mutex);
1450	memcpy(t.vhost_wwpn, vs->vs_vhost_wwpn, sizeof(t.vhost_wwpn));
1451	mutex_unlock(&vs->dev.mutex);
1452	vhost_scsi_clear_endpoint(vs, &t);
1453	vhost_dev_stop(&vs->dev);
1454	vhost_dev_cleanup(&vs->dev, false);
1455	/* Jobs can re-queue themselves in evt kick handler. Do extra flush. */
1456	vhost_scsi_flush(vs);
1457	kfree(vs->dev.vqs);
1458	vhost_scsi_free(vs);
1459	return 0;
1460}
1461
1462static long
1463vhost_scsi_ioctl(struct file *f,
1464		 unsigned int ioctl,
1465		 unsigned long arg)
1466{
1467	struct vhost_scsi *vs = f->private_data;
1468	struct vhost_scsi_target backend;
1469	void __user *argp = (void __user *)arg;
1470	u64 __user *featurep = argp;
1471	u32 __user *eventsp = argp;
1472	u32 events_missed;
1473	u64 features;
1474	int r, abi_version = VHOST_SCSI_ABI_VERSION;
1475	struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1476
1477	switch (ioctl) {
1478	case VHOST_SCSI_SET_ENDPOINT:
1479		if (copy_from_user(&backend, argp, sizeof backend))
1480			return -EFAULT;
1481		if (backend.reserved != 0)
1482			return -EOPNOTSUPP;
1483
1484		return vhost_scsi_set_endpoint(vs, &backend);
1485	case VHOST_SCSI_CLEAR_ENDPOINT:
1486		if (copy_from_user(&backend, argp, sizeof backend))
1487			return -EFAULT;
1488		if (backend.reserved != 0)
1489			return -EOPNOTSUPP;
1490
1491		return vhost_scsi_clear_endpoint(vs, &backend);
1492	case VHOST_SCSI_GET_ABI_VERSION:
1493		if (copy_to_user(argp, &abi_version, sizeof abi_version))
1494			return -EFAULT;
1495		return 0;
1496	case VHOST_SCSI_SET_EVENTS_MISSED:
1497		if (get_user(events_missed, eventsp))
1498			return -EFAULT;
1499		mutex_lock(&vq->mutex);
1500		vs->vs_events_missed = events_missed;
1501		mutex_unlock(&vq->mutex);
1502		return 0;
1503	case VHOST_SCSI_GET_EVENTS_MISSED:
1504		mutex_lock(&vq->mutex);
1505		events_missed = vs->vs_events_missed;
1506		mutex_unlock(&vq->mutex);
1507		if (put_user(events_missed, eventsp))
1508			return -EFAULT;
1509		return 0;
1510	case VHOST_GET_FEATURES:
1511		features = VHOST_SCSI_FEATURES;
1512		if (copy_to_user(featurep, &features, sizeof features))
1513			return -EFAULT;
1514		return 0;
1515	case VHOST_SET_FEATURES:
1516		if (copy_from_user(&features, featurep, sizeof features))
1517			return -EFAULT;
1518		return vhost_scsi_set_features(vs, features);
1519	default:
1520		mutex_lock(&vs->dev.mutex);
1521		r = vhost_dev_ioctl(&vs->dev, ioctl, argp);
1522		/* TODO: flush backend after dev ioctl. */
1523		if (r == -ENOIOCTLCMD)
1524			r = vhost_vring_ioctl(&vs->dev, ioctl, argp);
1525		mutex_unlock(&vs->dev.mutex);
1526		return r;
1527	}
1528}
1529
1530#ifdef CONFIG_COMPAT
1531static long vhost_scsi_compat_ioctl(struct file *f, unsigned int ioctl,
1532				unsigned long arg)
1533{
1534	return vhost_scsi_ioctl(f, ioctl, (unsigned long)compat_ptr(arg));
1535}
1536#endif
1537
1538static const struct file_operations vhost_scsi_fops = {
1539	.owner          = THIS_MODULE,
1540	.release        = vhost_scsi_release,
1541	.unlocked_ioctl = vhost_scsi_ioctl,
1542#ifdef CONFIG_COMPAT
1543	.compat_ioctl	= vhost_scsi_compat_ioctl,
1544#endif
1545	.open           = vhost_scsi_open,
1546	.llseek		= noop_llseek,
1547};
1548
1549static struct miscdevice vhost_scsi_misc = {
1550	MISC_DYNAMIC_MINOR,
1551	"vhost-scsi",
1552	&vhost_scsi_fops,
1553};
1554
1555static int __init vhost_scsi_register(void)
1556{
1557	return misc_register(&vhost_scsi_misc);
1558}
1559
1560static int vhost_scsi_deregister(void)
1561{
1562	return misc_deregister(&vhost_scsi_misc);
1563}
1564
1565static char *tcm_vhost_dump_proto_id(struct tcm_vhost_tport *tport)
1566{
1567	switch (tport->tport_proto_id) {
1568	case SCSI_PROTOCOL_SAS:
1569		return "SAS";
1570	case SCSI_PROTOCOL_FCP:
1571		return "FCP";
1572	case SCSI_PROTOCOL_ISCSI:
1573		return "iSCSI";
1574	default:
1575		break;
1576	}
1577
1578	return "Unknown";
1579}
1580
1581static void
1582tcm_vhost_do_plug(struct tcm_vhost_tpg *tpg,
1583		  struct se_lun *lun, bool plug)
1584{
1585
1586	struct vhost_scsi *vs = tpg->vhost_scsi;
1587	struct vhost_virtqueue *vq;
1588	u32 reason;
1589
1590	if (!vs)
1591		return;
1592
1593	mutex_lock(&vs->dev.mutex);
1594	if (!vhost_has_feature(&vs->dev, VIRTIO_SCSI_F_HOTPLUG)) {
1595		mutex_unlock(&vs->dev.mutex);
1596		return;
1597	}
1598
1599	if (plug)
1600		reason = VIRTIO_SCSI_EVT_RESET_RESCAN;
1601	else
1602		reason = VIRTIO_SCSI_EVT_RESET_REMOVED;
1603
1604	vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1605	mutex_lock(&vq->mutex);
1606	tcm_vhost_send_evt(vs, tpg, lun,
1607			VIRTIO_SCSI_T_TRANSPORT_RESET, reason);
 
1608	mutex_unlock(&vq->mutex);
1609	mutex_unlock(&vs->dev.mutex);
1610}
1611
1612static void tcm_vhost_hotplug(struct tcm_vhost_tpg *tpg, struct se_lun *lun)
1613{
1614	tcm_vhost_do_plug(tpg, lun, true);
1615}
1616
1617static void tcm_vhost_hotunplug(struct tcm_vhost_tpg *tpg, struct se_lun *lun)
1618{
1619	tcm_vhost_do_plug(tpg, lun, false);
1620}
1621
1622static int tcm_vhost_port_link(struct se_portal_group *se_tpg,
1623			       struct se_lun *lun)
1624{
1625	struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1626				struct tcm_vhost_tpg, se_tpg);
1627
1628	mutex_lock(&tcm_vhost_mutex);
1629
1630	mutex_lock(&tpg->tv_tpg_mutex);
1631	tpg->tv_tpg_port_count++;
1632	mutex_unlock(&tpg->tv_tpg_mutex);
1633
1634	tcm_vhost_hotplug(tpg, lun);
1635
1636	mutex_unlock(&tcm_vhost_mutex);
1637
1638	return 0;
1639}
1640
1641static void tcm_vhost_port_unlink(struct se_portal_group *se_tpg,
1642				  struct se_lun *lun)
1643{
1644	struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1645				struct tcm_vhost_tpg, se_tpg);
1646
1647	mutex_lock(&tcm_vhost_mutex);
1648
1649	mutex_lock(&tpg->tv_tpg_mutex);
1650	tpg->tv_tpg_port_count--;
1651	mutex_unlock(&tpg->tv_tpg_mutex);
1652
1653	tcm_vhost_hotunplug(tpg, lun);
1654
1655	mutex_unlock(&tcm_vhost_mutex);
1656}
1657
1658static struct se_node_acl *
1659tcm_vhost_make_nodeacl(struct se_portal_group *se_tpg,
1660		       struct config_group *group,
1661		       const char *name)
1662{
1663	struct se_node_acl *se_nacl, *se_nacl_new;
1664	struct tcm_vhost_nacl *nacl;
1665	u64 wwpn = 0;
1666	u32 nexus_depth;
1667
1668	/* tcm_vhost_parse_wwn(name, &wwpn, 1) < 0)
1669		return ERR_PTR(-EINVAL); */
1670	se_nacl_new = tcm_vhost_alloc_fabric_acl(se_tpg);
1671	if (!se_nacl_new)
1672		return ERR_PTR(-ENOMEM);
1673
1674	nexus_depth = 1;
1675	/*
1676	 * se_nacl_new may be released by core_tpg_add_initiator_node_acl()
1677	 * when converting a NodeACL from demo mode -> explict
1678	 */
1679	se_nacl = core_tpg_add_initiator_node_acl(se_tpg, se_nacl_new,
1680				name, nexus_depth);
1681	if (IS_ERR(se_nacl)) {
1682		tcm_vhost_release_fabric_acl(se_tpg, se_nacl_new);
1683		return se_nacl;
1684	}
1685	/*
1686	 * Locate our struct tcm_vhost_nacl and set the FC Nport WWPN
1687	 */
1688	nacl = container_of(se_nacl, struct tcm_vhost_nacl, se_node_acl);
1689	nacl->iport_wwpn = wwpn;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1690
1691	return se_nacl;
1692}
1693
1694static void tcm_vhost_drop_nodeacl(struct se_node_acl *se_acl)
 
1695{
1696	struct tcm_vhost_nacl *nacl = container_of(se_acl,
1697				struct tcm_vhost_nacl, se_node_acl);
1698	core_tpg_del_initiator_node_acl(se_acl->se_tpg, se_acl, 1);
1699	kfree(nacl);
 
1700}
1701
1702static void tcm_vhost_free_cmd_map_res(struct tcm_vhost_nexus *nexus,
1703				       struct se_session *se_sess)
 
 
 
 
 
 
 
1704{
1705	struct tcm_vhost_cmd *tv_cmd;
1706	unsigned int i;
1707
1708	if (!se_sess->sess_cmd_map)
1709		return;
1710
1711	for (i = 0; i < TCM_VHOST_DEFAULT_TAGS; i++) {
1712		tv_cmd = &((struct tcm_vhost_cmd *)se_sess->sess_cmd_map)[i];
 
 
 
 
1713
1714		kfree(tv_cmd->tvc_sgl);
1715		kfree(tv_cmd->tvc_upages);
 
 
 
 
 
 
 
 
 
 
 
1716	}
 
 
 
 
1717}
1718
1719static int tcm_vhost_make_nexus(struct tcm_vhost_tpg *tpg,
1720				const char *name)
1721{
1722	struct se_portal_group *se_tpg;
1723	struct se_session *se_sess;
1724	struct tcm_vhost_nexus *tv_nexus;
1725	struct tcm_vhost_cmd *tv_cmd;
1726	unsigned int i;
1727
1728	mutex_lock(&tpg->tv_tpg_mutex);
1729	if (tpg->tpg_nexus) {
1730		mutex_unlock(&tpg->tv_tpg_mutex);
1731		pr_debug("tpg->tpg_nexus already exists\n");
1732		return -EEXIST;
1733	}
1734	se_tpg = &tpg->se_tpg;
1735
1736	tv_nexus = kzalloc(sizeof(struct tcm_vhost_nexus), GFP_KERNEL);
1737	if (!tv_nexus) {
1738		mutex_unlock(&tpg->tv_tpg_mutex);
1739		pr_err("Unable to allocate struct tcm_vhost_nexus\n");
1740		return -ENOMEM;
1741	}
1742	/*
1743	 *  Initialize the struct se_session pointer and setup tagpool
1744	 *  for struct tcm_vhost_cmd descriptors
 
1745	 */
1746	tv_nexus->tvn_se_sess = transport_init_session_tags(
1747					TCM_VHOST_DEFAULT_TAGS,
1748					sizeof(struct tcm_vhost_cmd),
1749					TARGET_PROT_NORMAL);
 
 
1750	if (IS_ERR(tv_nexus->tvn_se_sess)) {
1751		mutex_unlock(&tpg->tv_tpg_mutex);
1752		kfree(tv_nexus);
1753		return -ENOMEM;
1754	}
1755	se_sess = tv_nexus->tvn_se_sess;
1756	for (i = 0; i < TCM_VHOST_DEFAULT_TAGS; i++) {
1757		tv_cmd = &((struct tcm_vhost_cmd *)se_sess->sess_cmd_map)[i];
1758
1759		tv_cmd->tvc_sgl = kzalloc(sizeof(struct scatterlist) *
1760					TCM_VHOST_PREALLOC_SGLS, GFP_KERNEL);
1761		if (!tv_cmd->tvc_sgl) {
1762			mutex_unlock(&tpg->tv_tpg_mutex);
1763			pr_err("Unable to allocate tv_cmd->tvc_sgl\n");
1764			goto out;
1765		}
1766
1767		tv_cmd->tvc_upages = kzalloc(sizeof(struct page *) *
1768					TCM_VHOST_PREALLOC_PAGES, GFP_KERNEL);
1769		if (!tv_cmd->tvc_upages) {
1770			mutex_unlock(&tpg->tv_tpg_mutex);
1771			pr_err("Unable to allocate tv_cmd->tvc_upages\n");
1772			goto out;
1773		}
1774	}
1775	/*
1776	 * Since we are running in 'demo mode' this call with generate a
1777	 * struct se_node_acl for the tcm_vhost struct se_portal_group with
1778	 * the SCSI Initiator port name of the passed configfs group 'name'.
1779	 */
1780	tv_nexus->tvn_se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
1781				se_tpg, (unsigned char *)name);
1782	if (!tv_nexus->tvn_se_sess->se_node_acl) {
1783		mutex_unlock(&tpg->tv_tpg_mutex);
1784		pr_debug("core_tpg_check_initiator_node_acl() failed"
1785				" for %s\n", name);
1786		goto out;
1787	}
1788	/*
1789	 * Now register the TCM vhost virtual I_T Nexus as active with the
1790	 * call to __transport_register_session()
1791	 */
1792	__transport_register_session(se_tpg, tv_nexus->tvn_se_sess->se_node_acl,
1793			tv_nexus->tvn_se_sess, tv_nexus);
1794	tpg->tpg_nexus = tv_nexus;
1795
1796	mutex_unlock(&tpg->tv_tpg_mutex);
1797	return 0;
1798
1799out:
1800	tcm_vhost_free_cmd_map_res(tv_nexus, se_sess);
1801	transport_free_session(se_sess);
1802	kfree(tv_nexus);
1803	return -ENOMEM;
1804}
1805
1806static int tcm_vhost_drop_nexus(struct tcm_vhost_tpg *tpg)
1807{
1808	struct se_session *se_sess;
1809	struct tcm_vhost_nexus *tv_nexus;
1810
1811	mutex_lock(&tpg->tv_tpg_mutex);
1812	tv_nexus = tpg->tpg_nexus;
1813	if (!tv_nexus) {
1814		mutex_unlock(&tpg->tv_tpg_mutex);
1815		return -ENODEV;
1816	}
1817
1818	se_sess = tv_nexus->tvn_se_sess;
1819	if (!se_sess) {
1820		mutex_unlock(&tpg->tv_tpg_mutex);
1821		return -ENODEV;
1822	}
1823
1824	if (tpg->tv_tpg_port_count != 0) {
1825		mutex_unlock(&tpg->tv_tpg_mutex);
1826		pr_err("Unable to remove TCM_vhost I_T Nexus with"
1827			" active TPG port count: %d\n",
1828			tpg->tv_tpg_port_count);
1829		return -EBUSY;
1830	}
1831
1832	if (tpg->tv_tpg_vhost_count != 0) {
1833		mutex_unlock(&tpg->tv_tpg_mutex);
1834		pr_err("Unable to remove TCM_vhost I_T Nexus with"
1835			" active TPG vhost count: %d\n",
1836			tpg->tv_tpg_vhost_count);
1837		return -EBUSY;
1838	}
1839
1840	pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated"
1841		" %s Initiator Port: %s\n", tcm_vhost_dump_proto_id(tpg->tport),
1842		tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1843
1844	tcm_vhost_free_cmd_map_res(tv_nexus, se_sess);
1845	/*
1846	 * Release the SCSI I_T Nexus to the emulated vhost Target Port
1847	 */
1848	transport_deregister_session(tv_nexus->tvn_se_sess);
1849	tpg->tpg_nexus = NULL;
1850	mutex_unlock(&tpg->tv_tpg_mutex);
1851
1852	kfree(tv_nexus);
1853	return 0;
1854}
1855
1856static ssize_t tcm_vhost_tpg_show_nexus(struct se_portal_group *se_tpg,
1857					char *page)
1858{
1859	struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1860				struct tcm_vhost_tpg, se_tpg);
1861	struct tcm_vhost_nexus *tv_nexus;
 
1862	ssize_t ret;
1863
1864	mutex_lock(&tpg->tv_tpg_mutex);
1865	tv_nexus = tpg->tpg_nexus;
1866	if (!tv_nexus) {
1867		mutex_unlock(&tpg->tv_tpg_mutex);
1868		return -ENODEV;
1869	}
1870	ret = snprintf(page, PAGE_SIZE, "%s\n",
1871			tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1872	mutex_unlock(&tpg->tv_tpg_mutex);
1873
1874	return ret;
1875}
1876
1877static ssize_t tcm_vhost_tpg_store_nexus(struct se_portal_group *se_tpg,
1878					 const char *page,
1879					 size_t count)
1880{
1881	struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1882				struct tcm_vhost_tpg, se_tpg);
1883	struct tcm_vhost_tport *tport_wwn = tpg->tport;
1884	unsigned char i_port[TCM_VHOST_NAMELEN], *ptr, *port_ptr;
1885	int ret;
1886	/*
1887	 * Shutdown the active I_T nexus if 'NULL' is passed..
1888	 */
1889	if (!strncmp(page, "NULL", 4)) {
1890		ret = tcm_vhost_drop_nexus(tpg);
1891		return (!ret) ? count : ret;
1892	}
1893	/*
1894	 * Otherwise make sure the passed virtual Initiator port WWN matches
1895	 * the fabric protocol_id set in tcm_vhost_make_tport(), and call
1896	 * tcm_vhost_make_nexus().
1897	 */
1898	if (strlen(page) >= TCM_VHOST_NAMELEN) {
1899		pr_err("Emulated NAA Sas Address: %s, exceeds"
1900				" max: %d\n", page, TCM_VHOST_NAMELEN);
1901		return -EINVAL;
1902	}
1903	snprintf(&i_port[0], TCM_VHOST_NAMELEN, "%s", page);
1904
1905	ptr = strstr(i_port, "naa.");
1906	if (ptr) {
1907		if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
1908			pr_err("Passed SAS Initiator Port %s does not"
1909				" match target port protoid: %s\n", i_port,
1910				tcm_vhost_dump_proto_id(tport_wwn));
1911			return -EINVAL;
1912		}
1913		port_ptr = &i_port[0];
1914		goto check_newline;
1915	}
1916	ptr = strstr(i_port, "fc.");
1917	if (ptr) {
1918		if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
1919			pr_err("Passed FCP Initiator Port %s does not"
1920				" match target port protoid: %s\n", i_port,
1921				tcm_vhost_dump_proto_id(tport_wwn));
1922			return -EINVAL;
1923		}
1924		port_ptr = &i_port[3]; /* Skip over "fc." */
1925		goto check_newline;
1926	}
1927	ptr = strstr(i_port, "iqn.");
1928	if (ptr) {
1929		if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
1930			pr_err("Passed iSCSI Initiator Port %s does not"
1931				" match target port protoid: %s\n", i_port,
1932				tcm_vhost_dump_proto_id(tport_wwn));
1933			return -EINVAL;
1934		}
1935		port_ptr = &i_port[0];
1936		goto check_newline;
1937	}
1938	pr_err("Unable to locate prefix for emulated Initiator Port:"
1939			" %s\n", i_port);
1940	return -EINVAL;
1941	/*
1942	 * Clear any trailing newline for the NAA WWN
1943	 */
1944check_newline:
1945	if (i_port[strlen(i_port)-1] == '\n')
1946		i_port[strlen(i_port)-1] = '\0';
1947
1948	ret = tcm_vhost_make_nexus(tpg, port_ptr);
1949	if (ret < 0)
1950		return ret;
1951
1952	return count;
1953}
1954
1955TF_TPG_BASE_ATTR(tcm_vhost, nexus, S_IRUGO | S_IWUSR);
1956
1957static struct configfs_attribute *tcm_vhost_tpg_attrs[] = {
1958	&tcm_vhost_tpg_nexus.attr,
1959	NULL,
1960};
1961
1962static struct se_portal_group *
1963tcm_vhost_make_tpg(struct se_wwn *wwn,
1964		   struct config_group *group,
1965		   const char *name)
1966{
1967	struct tcm_vhost_tport *tport = container_of(wwn,
1968			struct tcm_vhost_tport, tport_wwn);
1969
1970	struct tcm_vhost_tpg *tpg;
1971	unsigned long tpgt;
1972	int ret;
1973
1974	if (strstr(name, "tpgt_") != name)
1975		return ERR_PTR(-EINVAL);
1976	if (kstrtoul(name + 5, 10, &tpgt) || tpgt > UINT_MAX)
1977		return ERR_PTR(-EINVAL);
1978
1979	tpg = kzalloc(sizeof(struct tcm_vhost_tpg), GFP_KERNEL);
1980	if (!tpg) {
1981		pr_err("Unable to allocate struct tcm_vhost_tpg");
1982		return ERR_PTR(-ENOMEM);
1983	}
1984	mutex_init(&tpg->tv_tpg_mutex);
1985	INIT_LIST_HEAD(&tpg->tv_tpg_list);
1986	tpg->tport = tport;
1987	tpg->tport_tpgt = tpgt;
1988
1989	ret = core_tpg_register(&tcm_vhost_fabric_configfs->tf_ops, wwn,
1990				&tpg->se_tpg, tpg, TRANSPORT_TPG_TYPE_NORMAL);
1991	if (ret < 0) {
1992		kfree(tpg);
1993		return NULL;
1994	}
1995	mutex_lock(&tcm_vhost_mutex);
1996	list_add_tail(&tpg->tv_tpg_list, &tcm_vhost_list);
1997	mutex_unlock(&tcm_vhost_mutex);
1998
1999	return &tpg->se_tpg;
2000}
2001
2002static void tcm_vhost_drop_tpg(struct se_portal_group *se_tpg)
2003{
2004	struct tcm_vhost_tpg *tpg = container_of(se_tpg,
2005				struct tcm_vhost_tpg, se_tpg);
2006
2007	mutex_lock(&tcm_vhost_mutex);
2008	list_del(&tpg->tv_tpg_list);
2009	mutex_unlock(&tcm_vhost_mutex);
2010	/*
2011	 * Release the virtual I_T Nexus for this vhost TPG
2012	 */
2013	tcm_vhost_drop_nexus(tpg);
2014	/*
2015	 * Deregister the se_tpg from TCM..
2016	 */
2017	core_tpg_deregister(se_tpg);
2018	kfree(tpg);
2019}
2020
2021static struct se_wwn *
2022tcm_vhost_make_tport(struct target_fabric_configfs *tf,
2023		     struct config_group *group,
2024		     const char *name)
2025{
2026	struct tcm_vhost_tport *tport;
2027	char *ptr;
2028	u64 wwpn = 0;
2029	int off = 0;
2030
2031	/* if (tcm_vhost_parse_wwn(name, &wwpn, 1) < 0)
2032		return ERR_PTR(-EINVAL); */
2033
2034	tport = kzalloc(sizeof(struct tcm_vhost_tport), GFP_KERNEL);
2035	if (!tport) {
2036		pr_err("Unable to allocate struct tcm_vhost_tport");
2037		return ERR_PTR(-ENOMEM);
2038	}
2039	tport->tport_wwpn = wwpn;
2040	/*
2041	 * Determine the emulated Protocol Identifier and Target Port Name
2042	 * based on the incoming configfs directory name.
2043	 */
2044	ptr = strstr(name, "naa.");
2045	if (ptr) {
2046		tport->tport_proto_id = SCSI_PROTOCOL_SAS;
2047		goto check_len;
2048	}
2049	ptr = strstr(name, "fc.");
2050	if (ptr) {
2051		tport->tport_proto_id = SCSI_PROTOCOL_FCP;
2052		off = 3; /* Skip over "fc." */
2053		goto check_len;
2054	}
2055	ptr = strstr(name, "iqn.");
2056	if (ptr) {
2057		tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
2058		goto check_len;
2059	}
2060
2061	pr_err("Unable to locate prefix for emulated Target Port:"
2062			" %s\n", name);
2063	kfree(tport);
2064	return ERR_PTR(-EINVAL);
2065
2066check_len:
2067	if (strlen(name) >= TCM_VHOST_NAMELEN) {
2068		pr_err("Emulated %s Address: %s, exceeds"
2069			" max: %d\n", name, tcm_vhost_dump_proto_id(tport),
2070			TCM_VHOST_NAMELEN);
2071		kfree(tport);
2072		return ERR_PTR(-EINVAL);
2073	}
2074	snprintf(&tport->tport_name[0], TCM_VHOST_NAMELEN, "%s", &name[off]);
2075
2076	pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target"
2077		" %s Address: %s\n", tcm_vhost_dump_proto_id(tport), name);
2078
2079	return &tport->tport_wwn;
2080}
2081
2082static void tcm_vhost_drop_tport(struct se_wwn *wwn)
2083{
2084	struct tcm_vhost_tport *tport = container_of(wwn,
2085				struct tcm_vhost_tport, tport_wwn);
2086
2087	pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target"
2088		" %s Address: %s\n", tcm_vhost_dump_proto_id(tport),
2089		tport->tport_name);
2090
2091	kfree(tport);
2092}
2093
2094static ssize_t
2095tcm_vhost_wwn_show_attr_version(struct target_fabric_configfs *tf,
2096				char *page)
2097{
2098	return sprintf(page, "TCM_VHOST fabric module %s on %s/%s"
2099		"on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname,
2100		utsname()->machine);
2101}
2102
2103TF_WWN_ATTR_RO(tcm_vhost, version);
2104
2105static struct configfs_attribute *tcm_vhost_wwn_attrs[] = {
2106	&tcm_vhost_wwn_version.attr,
2107	NULL,
2108};
2109
2110static struct target_core_fabric_ops tcm_vhost_ops = {
2111	.get_fabric_name		= tcm_vhost_get_fabric_name,
2112	.get_fabric_proto_ident		= tcm_vhost_get_fabric_proto_ident,
2113	.tpg_get_wwn			= tcm_vhost_get_fabric_wwn,
2114	.tpg_get_tag			= tcm_vhost_get_tag,
2115	.tpg_get_default_depth		= tcm_vhost_get_default_depth,
2116	.tpg_get_pr_transport_id	= tcm_vhost_get_pr_transport_id,
2117	.tpg_get_pr_transport_id_len	= tcm_vhost_get_pr_transport_id_len,
2118	.tpg_parse_pr_out_transport_id	= tcm_vhost_parse_pr_out_transport_id,
2119	.tpg_check_demo_mode		= tcm_vhost_check_true,
2120	.tpg_check_demo_mode_cache	= tcm_vhost_check_true,
2121	.tpg_check_demo_mode_write_protect = tcm_vhost_check_false,
2122	.tpg_check_prod_mode_write_protect = tcm_vhost_check_false,
2123	.tpg_alloc_fabric_acl		= tcm_vhost_alloc_fabric_acl,
2124	.tpg_release_fabric_acl		= tcm_vhost_release_fabric_acl,
2125	.tpg_get_inst_index		= tcm_vhost_tpg_get_inst_index,
2126	.release_cmd			= tcm_vhost_release_cmd,
2127	.check_stop_free		= vhost_scsi_check_stop_free,
2128	.shutdown_session		= tcm_vhost_shutdown_session,
2129	.close_session			= tcm_vhost_close_session,
2130	.sess_get_index			= tcm_vhost_sess_get_index,
2131	.sess_get_initiator_sid		= NULL,
2132	.write_pending			= tcm_vhost_write_pending,
2133	.write_pending_status		= tcm_vhost_write_pending_status,
2134	.set_default_node_attributes	= tcm_vhost_set_default_node_attrs,
2135	.get_task_tag			= tcm_vhost_get_task_tag,
2136	.get_cmd_state			= tcm_vhost_get_cmd_state,
2137	.queue_data_in			= tcm_vhost_queue_data_in,
2138	.queue_status			= tcm_vhost_queue_status,
2139	.queue_tm_rsp			= tcm_vhost_queue_tm_rsp,
2140	.aborted_task			= tcm_vhost_aborted_task,
2141	/*
2142	 * Setup callers for generic logic in target_core_fabric_configfs.c
2143	 */
2144	.fabric_make_wwn		= tcm_vhost_make_tport,
2145	.fabric_drop_wwn		= tcm_vhost_drop_tport,
2146	.fabric_make_tpg		= tcm_vhost_make_tpg,
2147	.fabric_drop_tpg		= tcm_vhost_drop_tpg,
2148	.fabric_post_link		= tcm_vhost_port_link,
2149	.fabric_pre_unlink		= tcm_vhost_port_unlink,
2150	.fabric_make_np			= NULL,
2151	.fabric_drop_np			= NULL,
2152	.fabric_make_nodeacl		= tcm_vhost_make_nodeacl,
2153	.fabric_drop_nodeacl		= tcm_vhost_drop_nodeacl,
2154};
2155
2156static int tcm_vhost_register_configfs(void)
2157{
2158	struct target_fabric_configfs *fabric;
2159	int ret;
2160
2161	pr_debug("TCM_VHOST fabric module %s on %s/%s"
2162		" on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname,
2163		utsname()->machine);
2164	/*
2165	 * Register the top level struct config_item_type with TCM core
2166	 */
2167	fabric = target_fabric_configfs_init(THIS_MODULE, "vhost");
2168	if (IS_ERR(fabric)) {
2169		pr_err("target_fabric_configfs_init() failed\n");
2170		return PTR_ERR(fabric);
2171	}
2172	/*
2173	 * Setup fabric->tf_ops from our local tcm_vhost_ops
2174	 */
2175	fabric->tf_ops = tcm_vhost_ops;
2176	/*
2177	 * Setup default attribute lists for various fabric->tf_cit_tmpl
2178	 */
2179	fabric->tf_cit_tmpl.tfc_wwn_cit.ct_attrs = tcm_vhost_wwn_attrs;
2180	fabric->tf_cit_tmpl.tfc_tpg_base_cit.ct_attrs = tcm_vhost_tpg_attrs;
2181	fabric->tf_cit_tmpl.tfc_tpg_attrib_cit.ct_attrs = NULL;
2182	fabric->tf_cit_tmpl.tfc_tpg_param_cit.ct_attrs = NULL;
2183	fabric->tf_cit_tmpl.tfc_tpg_np_base_cit.ct_attrs = NULL;
2184	fabric->tf_cit_tmpl.tfc_tpg_nacl_base_cit.ct_attrs = NULL;
2185	fabric->tf_cit_tmpl.tfc_tpg_nacl_attrib_cit.ct_attrs = NULL;
2186	fabric->tf_cit_tmpl.tfc_tpg_nacl_auth_cit.ct_attrs = NULL;
2187	fabric->tf_cit_tmpl.tfc_tpg_nacl_param_cit.ct_attrs = NULL;
2188	/*
2189	 * Register the fabric for use within TCM
2190	 */
2191	ret = target_fabric_configfs_register(fabric);
2192	if (ret < 0) {
2193		pr_err("target_fabric_configfs_register() failed"
2194				" for TCM_VHOST\n");
2195		return ret;
2196	}
2197	/*
2198	 * Setup our local pointer to *fabric
2199	 */
2200	tcm_vhost_fabric_configfs = fabric;
2201	pr_debug("TCM_VHOST[0] - Set fabric -> tcm_vhost_fabric_configfs\n");
2202	return 0;
2203};
2204
2205static void tcm_vhost_deregister_configfs(void)
2206{
2207	if (!tcm_vhost_fabric_configfs)
2208		return;
2209
2210	target_fabric_configfs_deregister(tcm_vhost_fabric_configfs);
2211	tcm_vhost_fabric_configfs = NULL;
2212	pr_debug("TCM_VHOST[0] - Cleared tcm_vhost_fabric_configfs\n");
2213};
2214
2215static int __init tcm_vhost_init(void)
2216{
2217	int ret = -ENOMEM;
2218	/*
2219	 * Use our own dedicated workqueue for submitting I/O into
2220	 * target core to avoid contention within system_wq.
2221	 */
2222	tcm_vhost_workqueue = alloc_workqueue("tcm_vhost", 0, 0);
2223	if (!tcm_vhost_workqueue)
2224		goto out;
2225
2226	ret = vhost_scsi_register();
2227	if (ret < 0)
2228		goto out_destroy_workqueue;
2229
2230	ret = tcm_vhost_register_configfs();
2231	if (ret < 0)
2232		goto out_vhost_scsi_deregister;
2233
2234	return 0;
2235
2236out_vhost_scsi_deregister:
2237	vhost_scsi_deregister();
2238out_destroy_workqueue:
2239	destroy_workqueue(tcm_vhost_workqueue);
2240out:
2241	return ret;
2242};
2243
2244static void tcm_vhost_exit(void)
2245{
2246	tcm_vhost_deregister_configfs();
2247	vhost_scsi_deregister();
2248	destroy_workqueue(tcm_vhost_workqueue);
2249};
2250
2251MODULE_DESCRIPTION("VHOST_SCSI series fabric driver");
2252MODULE_ALIAS("tcm_vhost");
2253MODULE_LICENSE("GPL");
2254module_init(tcm_vhost_init);
2255module_exit(tcm_vhost_exit);