Linux Audio

Check our new training course

Loading...
Note: File does not exist in v3.1.
   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/vmalloc.h>
  39#include <linux/miscdevice.h>
  40#include <asm/unaligned.h>
  41#include <scsi/scsi_common.h>
  42#include <scsi/scsi_proto.h>
  43#include <target/target_core_base.h>
  44#include <target/target_core_fabric.h>
  45#include <linux/vhost.h>
  46#include <linux/virtio_scsi.h>
  47#include <linux/llist.h>
  48#include <linux/bitmap.h>
  49
  50#include "vhost.h"
  51
  52#define VHOST_SCSI_VERSION  "v0.1"
  53#define VHOST_SCSI_NAMELEN 256
  54#define VHOST_SCSI_MAX_CDB_SIZE 32
  55#define VHOST_SCSI_PREALLOC_SGLS 2048
  56#define VHOST_SCSI_PREALLOC_UPAGES 2048
  57#define VHOST_SCSI_PREALLOC_PROT_SGLS 2048
  58
  59/* Max number of requests before requeueing the job.
  60 * Using this limit prevents one virtqueue from starving others with
  61 * request.
  62 */
  63#define VHOST_SCSI_WEIGHT 256
  64
  65struct vhost_scsi_inflight {
  66	/* Wait for the flush operation to finish */
  67	struct completion comp;
  68	/* Refcount for the inflight reqs */
  69	struct kref kref;
  70};
  71
  72struct vhost_scsi_cmd {
  73	/* Descriptor from vhost_get_vq_desc() for virt_queue segment */
  74	int tvc_vq_desc;
  75	/* virtio-scsi initiator task attribute */
  76	int tvc_task_attr;
  77	/* virtio-scsi response incoming iovecs */
  78	int tvc_in_iovs;
  79	/* virtio-scsi initiator data direction */
  80	enum dma_data_direction tvc_data_direction;
  81	/* Expected data transfer length from virtio-scsi header */
  82	u32 tvc_exp_data_len;
  83	/* The Tag from include/linux/virtio_scsi.h:struct virtio_scsi_cmd_req */
  84	u64 tvc_tag;
  85	/* The number of scatterlists associated with this cmd */
  86	u32 tvc_sgl_count;
  87	u32 tvc_prot_sgl_count;
  88	/* Saved unpacked SCSI LUN for vhost_scsi_target_queue_cmd() */
  89	u32 tvc_lun;
  90	/* Pointer to the SGL formatted memory from virtio-scsi */
  91	struct scatterlist *tvc_sgl;
  92	struct scatterlist *tvc_prot_sgl;
  93	struct page **tvc_upages;
  94	/* Pointer to response header iovec */
  95	struct iovec tvc_resp_iov;
  96	/* Pointer to vhost_scsi for our device */
  97	struct vhost_scsi *tvc_vhost;
  98	/* Pointer to vhost_virtqueue for the cmd */
  99	struct vhost_virtqueue *tvc_vq;
 100	/* Pointer to vhost nexus memory */
 101	struct vhost_scsi_nexus *tvc_nexus;
 102	/* The TCM I/O descriptor that is accessed via container_of() */
 103	struct se_cmd tvc_se_cmd;
 104	/* Copy of the incoming SCSI command descriptor block (CDB) */
 105	unsigned char tvc_cdb[VHOST_SCSI_MAX_CDB_SIZE];
 106	/* Sense buffer that will be mapped into outgoing status */
 107	unsigned char tvc_sense_buf[TRANSPORT_SENSE_BUFFER];
 108	/* Completed commands list, serviced from vhost worker thread */
 109	struct llist_node tvc_completion_list;
 110	/* Used to track inflight cmd */
 111	struct vhost_scsi_inflight *inflight;
 112};
 113
 114struct vhost_scsi_nexus {
 115	/* Pointer to TCM session for I_T Nexus */
 116	struct se_session *tvn_se_sess;
 117};
 118
 119struct vhost_scsi_tpg {
 120	/* Vhost port target portal group tag for TCM */
 121	u16 tport_tpgt;
 122	/* Used to track number of TPG Port/Lun Links wrt to explict I_T Nexus shutdown */
 123	int tv_tpg_port_count;
 124	/* Used for vhost_scsi device reference to tpg_nexus, protected by tv_tpg_mutex */
 125	int tv_tpg_vhost_count;
 126	/* Used for enabling T10-PI with legacy devices */
 127	int tv_fabric_prot_type;
 128	/* list for vhost_scsi_list */
 129	struct list_head tv_tpg_list;
 130	/* Used to protect access for tpg_nexus */
 131	struct mutex tv_tpg_mutex;
 132	/* Pointer to the TCM VHost I_T Nexus for this TPG endpoint */
 133	struct vhost_scsi_nexus *tpg_nexus;
 134	/* Pointer back to vhost_scsi_tport */
 135	struct vhost_scsi_tport *tport;
 136	/* Returned by vhost_scsi_make_tpg() */
 137	struct se_portal_group se_tpg;
 138	/* Pointer back to vhost_scsi, protected by tv_tpg_mutex */
 139	struct vhost_scsi *vhost_scsi;
 140	struct list_head tmf_queue;
 141};
 142
 143struct vhost_scsi_tport {
 144	/* SCSI protocol the tport is providing */
 145	u8 tport_proto_id;
 146	/* Binary World Wide unique Port Name for Vhost Target port */
 147	u64 tport_wwpn;
 148	/* ASCII formatted WWPN for Vhost Target port */
 149	char tport_name[VHOST_SCSI_NAMELEN];
 150	/* Returned by vhost_scsi_make_tport() */
 151	struct se_wwn tport_wwn;
 152};
 153
 154struct vhost_scsi_evt {
 155	/* event to be sent to guest */
 156	struct virtio_scsi_event event;
 157	/* event list, serviced from vhost worker thread */
 158	struct llist_node list;
 159};
 160
 161enum {
 162	VHOST_SCSI_VQ_CTL = 0,
 163	VHOST_SCSI_VQ_EVT = 1,
 164	VHOST_SCSI_VQ_IO = 2,
 165};
 166
 167/* Note: can't set VIRTIO_F_VERSION_1 yet, since that implies ANY_LAYOUT. */
 168enum {
 169	VHOST_SCSI_FEATURES = VHOST_FEATURES | (1ULL << VIRTIO_SCSI_F_HOTPLUG) |
 170					       (1ULL << VIRTIO_SCSI_F_T10_PI)
 171};
 172
 173#define VHOST_SCSI_MAX_TARGET	256
 174#define VHOST_SCSI_MAX_VQ	128
 175#define VHOST_SCSI_MAX_EVENT	128
 176
 177struct vhost_scsi_virtqueue {
 178	struct vhost_virtqueue vq;
 179	/*
 180	 * Reference counting for inflight reqs, used for flush operation. At
 181	 * each time, one reference tracks new commands submitted, while we
 182	 * wait for another one to reach 0.
 183	 */
 184	struct vhost_scsi_inflight inflights[2];
 185	/*
 186	 * Indicate current inflight in use, protected by vq->mutex.
 187	 * Writers must also take dev mutex and flush under it.
 188	 */
 189	int inflight_idx;
 190	struct vhost_scsi_cmd *scsi_cmds;
 191	struct sbitmap scsi_tags;
 192	int max_cmds;
 193};
 194
 195struct vhost_scsi {
 196	/* Protected by vhost_scsi->dev.mutex */
 197	struct vhost_scsi_tpg **vs_tpg;
 198	char vs_vhost_wwpn[TRANSPORT_IQN_LEN];
 199
 200	struct vhost_dev dev;
 201	struct vhost_scsi_virtqueue vqs[VHOST_SCSI_MAX_VQ];
 202
 203	struct vhost_work vs_completion_work; /* cmd completion work item */
 204	struct llist_head vs_completion_list; /* cmd completion queue */
 205
 206	struct vhost_work vs_event_work; /* evt injection work item */
 207	struct llist_head vs_event_list; /* evt injection queue */
 208
 209	bool vs_events_missed; /* any missed events, protected by vq->mutex */
 210	int vs_events_nr; /* num of pending events, protected by vq->mutex */
 211};
 212
 213struct vhost_scsi_tmf {
 214	struct vhost_work vwork;
 215	struct vhost_scsi_tpg *tpg;
 216	struct vhost_scsi *vhost;
 217	struct vhost_scsi_virtqueue *svq;
 218	struct list_head queue_entry;
 219
 220	struct se_cmd se_cmd;
 221	u8 scsi_resp;
 222	struct vhost_scsi_inflight *inflight;
 223	struct iovec resp_iov;
 224	int in_iovs;
 225	int vq_desc;
 226};
 227
 228/*
 229 * Context for processing request and control queue operations.
 230 */
 231struct vhost_scsi_ctx {
 232	int head;
 233	unsigned int out, in;
 234	size_t req_size, rsp_size;
 235	size_t out_size, in_size;
 236	u8 *target, *lunp;
 237	void *req;
 238	struct iov_iter out_iter;
 239};
 240
 241/* Global spinlock to protect vhost_scsi TPG list for vhost IOCTL access */
 242static DEFINE_MUTEX(vhost_scsi_mutex);
 243static LIST_HEAD(vhost_scsi_list);
 244
 245static void vhost_scsi_done_inflight(struct kref *kref)
 246{
 247	struct vhost_scsi_inflight *inflight;
 248
 249	inflight = container_of(kref, struct vhost_scsi_inflight, kref);
 250	complete(&inflight->comp);
 251}
 252
 253static void vhost_scsi_init_inflight(struct vhost_scsi *vs,
 254				    struct vhost_scsi_inflight *old_inflight[])
 255{
 256	struct vhost_scsi_inflight *new_inflight;
 257	struct vhost_virtqueue *vq;
 258	int idx, i;
 259
 260	for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
 261		vq = &vs->vqs[i].vq;
 262
 263		mutex_lock(&vq->mutex);
 264
 265		/* store old infight */
 266		idx = vs->vqs[i].inflight_idx;
 267		if (old_inflight)
 268			old_inflight[i] = &vs->vqs[i].inflights[idx];
 269
 270		/* setup new infight */
 271		vs->vqs[i].inflight_idx = idx ^ 1;
 272		new_inflight = &vs->vqs[i].inflights[idx ^ 1];
 273		kref_init(&new_inflight->kref);
 274		init_completion(&new_inflight->comp);
 275
 276		mutex_unlock(&vq->mutex);
 277	}
 278}
 279
 280static struct vhost_scsi_inflight *
 281vhost_scsi_get_inflight(struct vhost_virtqueue *vq)
 282{
 283	struct vhost_scsi_inflight *inflight;
 284	struct vhost_scsi_virtqueue *svq;
 285
 286	svq = container_of(vq, struct vhost_scsi_virtqueue, vq);
 287	inflight = &svq->inflights[svq->inflight_idx];
 288	kref_get(&inflight->kref);
 289
 290	return inflight;
 291}
 292
 293static void vhost_scsi_put_inflight(struct vhost_scsi_inflight *inflight)
 294{
 295	kref_put(&inflight->kref, vhost_scsi_done_inflight);
 296}
 297
 298static int vhost_scsi_check_true(struct se_portal_group *se_tpg)
 299{
 300	return 1;
 301}
 302
 303static int vhost_scsi_check_false(struct se_portal_group *se_tpg)
 304{
 305	return 0;
 306}
 307
 308static char *vhost_scsi_get_fabric_wwn(struct se_portal_group *se_tpg)
 309{
 310	struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 311				struct vhost_scsi_tpg, se_tpg);
 312	struct vhost_scsi_tport *tport = tpg->tport;
 313
 314	return &tport->tport_name[0];
 315}
 316
 317static u16 vhost_scsi_get_tpgt(struct se_portal_group *se_tpg)
 318{
 319	struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 320				struct vhost_scsi_tpg, se_tpg);
 321	return tpg->tport_tpgt;
 322}
 323
 324static int vhost_scsi_check_prot_fabric_only(struct se_portal_group *se_tpg)
 325{
 326	struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 327				struct vhost_scsi_tpg, se_tpg);
 328
 329	return tpg->tv_fabric_prot_type;
 330}
 331
 332static u32 vhost_scsi_tpg_get_inst_index(struct se_portal_group *se_tpg)
 333{
 334	return 1;
 335}
 336
 337static void vhost_scsi_release_cmd_res(struct se_cmd *se_cmd)
 338{
 339	struct vhost_scsi_cmd *tv_cmd = container_of(se_cmd,
 340				struct vhost_scsi_cmd, tvc_se_cmd);
 341	struct vhost_scsi_virtqueue *svq = container_of(tv_cmd->tvc_vq,
 342				struct vhost_scsi_virtqueue, vq);
 343	struct vhost_scsi_inflight *inflight = tv_cmd->inflight;
 344	int i;
 345
 346	if (tv_cmd->tvc_sgl_count) {
 347		for (i = 0; i < tv_cmd->tvc_sgl_count; i++)
 348			put_page(sg_page(&tv_cmd->tvc_sgl[i]));
 349	}
 350	if (tv_cmd->tvc_prot_sgl_count) {
 351		for (i = 0; i < tv_cmd->tvc_prot_sgl_count; i++)
 352			put_page(sg_page(&tv_cmd->tvc_prot_sgl[i]));
 353	}
 354
 355	sbitmap_clear_bit(&svq->scsi_tags, se_cmd->map_tag);
 356	vhost_scsi_put_inflight(inflight);
 357}
 358
 359static void vhost_scsi_release_tmf_res(struct vhost_scsi_tmf *tmf)
 360{
 361	struct vhost_scsi_tpg *tpg = tmf->tpg;
 362	struct vhost_scsi_inflight *inflight = tmf->inflight;
 363
 364	mutex_lock(&tpg->tv_tpg_mutex);
 365	list_add_tail(&tpg->tmf_queue, &tmf->queue_entry);
 366	mutex_unlock(&tpg->tv_tpg_mutex);
 367	vhost_scsi_put_inflight(inflight);
 368}
 369
 370static void vhost_scsi_release_cmd(struct se_cmd *se_cmd)
 371{
 372	if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB) {
 373		struct vhost_scsi_tmf *tmf = container_of(se_cmd,
 374					struct vhost_scsi_tmf, se_cmd);
 375
 376		vhost_work_queue(&tmf->vhost->dev, &tmf->vwork);
 377	} else {
 378		struct vhost_scsi_cmd *cmd = container_of(se_cmd,
 379					struct vhost_scsi_cmd, tvc_se_cmd);
 380		struct vhost_scsi *vs = cmd->tvc_vhost;
 381
 382		llist_add(&cmd->tvc_completion_list, &vs->vs_completion_list);
 383		vhost_work_queue(&vs->dev, &vs->vs_completion_work);
 384	}
 385}
 386
 387static u32 vhost_scsi_sess_get_index(struct se_session *se_sess)
 388{
 389	return 0;
 390}
 391
 392static int vhost_scsi_write_pending(struct se_cmd *se_cmd)
 393{
 394	/* Go ahead and process the write immediately */
 395	target_execute_cmd(se_cmd);
 396	return 0;
 397}
 398
 399static void vhost_scsi_set_default_node_attrs(struct se_node_acl *nacl)
 400{
 401	return;
 402}
 403
 404static int vhost_scsi_get_cmd_state(struct se_cmd *se_cmd)
 405{
 406	return 0;
 407}
 408
 409static int vhost_scsi_queue_data_in(struct se_cmd *se_cmd)
 410{
 411	transport_generic_free_cmd(se_cmd, 0);
 412	return 0;
 413}
 414
 415static int vhost_scsi_queue_status(struct se_cmd *se_cmd)
 416{
 417	transport_generic_free_cmd(se_cmd, 0);
 418	return 0;
 419}
 420
 421static void vhost_scsi_queue_tm_rsp(struct se_cmd *se_cmd)
 422{
 423	struct vhost_scsi_tmf *tmf = container_of(se_cmd, struct vhost_scsi_tmf,
 424						  se_cmd);
 425
 426	tmf->scsi_resp = se_cmd->se_tmr_req->response;
 427	transport_generic_free_cmd(&tmf->se_cmd, 0);
 428}
 429
 430static void vhost_scsi_aborted_task(struct se_cmd *se_cmd)
 431{
 432	return;
 433}
 434
 435static void vhost_scsi_free_evt(struct vhost_scsi *vs, struct vhost_scsi_evt *evt)
 436{
 437	vs->vs_events_nr--;
 438	kfree(evt);
 439}
 440
 441static struct vhost_scsi_evt *
 442vhost_scsi_allocate_evt(struct vhost_scsi *vs,
 443		       u32 event, u32 reason)
 444{
 445	struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 446	struct vhost_scsi_evt *evt;
 447
 448	if (vs->vs_events_nr > VHOST_SCSI_MAX_EVENT) {
 449		vs->vs_events_missed = true;
 450		return NULL;
 451	}
 452
 453	evt = kzalloc(sizeof(*evt), GFP_KERNEL);
 454	if (!evt) {
 455		vq_err(vq, "Failed to allocate vhost_scsi_evt\n");
 456		vs->vs_events_missed = true;
 457		return NULL;
 458	}
 459
 460	evt->event.event = cpu_to_vhost32(vq, event);
 461	evt->event.reason = cpu_to_vhost32(vq, reason);
 462	vs->vs_events_nr++;
 463
 464	return evt;
 465}
 466
 467static int vhost_scsi_check_stop_free(struct se_cmd *se_cmd)
 468{
 469	return target_put_sess_cmd(se_cmd);
 470}
 471
 472static void
 473vhost_scsi_do_evt_work(struct vhost_scsi *vs, struct vhost_scsi_evt *evt)
 474{
 475	struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 476	struct virtio_scsi_event *event = &evt->event;
 477	struct virtio_scsi_event __user *eventp;
 478	unsigned out, in;
 479	int head, ret;
 480
 481	if (!vhost_vq_get_backend(vq)) {
 482		vs->vs_events_missed = true;
 483		return;
 484	}
 485
 486again:
 487	vhost_disable_notify(&vs->dev, vq);
 488	head = vhost_get_vq_desc(vq, vq->iov,
 489			ARRAY_SIZE(vq->iov), &out, &in,
 490			NULL, NULL);
 491	if (head < 0) {
 492		vs->vs_events_missed = true;
 493		return;
 494	}
 495	if (head == vq->num) {
 496		if (vhost_enable_notify(&vs->dev, vq))
 497			goto again;
 498		vs->vs_events_missed = true;
 499		return;
 500	}
 501
 502	if ((vq->iov[out].iov_len != sizeof(struct virtio_scsi_event))) {
 503		vq_err(vq, "Expecting virtio_scsi_event, got %zu bytes\n",
 504				vq->iov[out].iov_len);
 505		vs->vs_events_missed = true;
 506		return;
 507	}
 508
 509	if (vs->vs_events_missed) {
 510		event->event |= cpu_to_vhost32(vq, VIRTIO_SCSI_T_EVENTS_MISSED);
 511		vs->vs_events_missed = false;
 512	}
 513
 514	eventp = vq->iov[out].iov_base;
 515	ret = __copy_to_user(eventp, event, sizeof(*event));
 516	if (!ret)
 517		vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 518	else
 519		vq_err(vq, "Faulted on vhost_scsi_send_event\n");
 520}
 521
 522static void vhost_scsi_evt_work(struct vhost_work *work)
 523{
 524	struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 525					vs_event_work);
 526	struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 527	struct vhost_scsi_evt *evt, *t;
 528	struct llist_node *llnode;
 529
 530	mutex_lock(&vq->mutex);
 531	llnode = llist_del_all(&vs->vs_event_list);
 532	llist_for_each_entry_safe(evt, t, llnode, list) {
 533		vhost_scsi_do_evt_work(vs, evt);
 534		vhost_scsi_free_evt(vs, evt);
 535	}
 536	mutex_unlock(&vq->mutex);
 537}
 538
 539/* Fill in status and signal that we are done processing this command
 540 *
 541 * This is scheduled in the vhost work queue so we are called with the owner
 542 * process mm and can access the vring.
 543 */
 544static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
 545{
 546	struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 547					vs_completion_work);
 548	DECLARE_BITMAP(signal, VHOST_SCSI_MAX_VQ);
 549	struct virtio_scsi_cmd_resp v_rsp;
 550	struct vhost_scsi_cmd *cmd, *t;
 551	struct llist_node *llnode;
 552	struct se_cmd *se_cmd;
 553	struct iov_iter iov_iter;
 554	int ret, vq;
 555
 556	bitmap_zero(signal, VHOST_SCSI_MAX_VQ);
 557	llnode = llist_del_all(&vs->vs_completion_list);
 558	llist_for_each_entry_safe(cmd, t, llnode, tvc_completion_list) {
 559		se_cmd = &cmd->tvc_se_cmd;
 560
 561		pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__,
 562			cmd, se_cmd->residual_count, se_cmd->scsi_status);
 563
 564		memset(&v_rsp, 0, sizeof(v_rsp));
 565		v_rsp.resid = cpu_to_vhost32(cmd->tvc_vq, se_cmd->residual_count);
 566		/* TODO is status_qualifier field needed? */
 567		v_rsp.status = se_cmd->scsi_status;
 568		v_rsp.sense_len = cpu_to_vhost32(cmd->tvc_vq,
 569						 se_cmd->scsi_sense_length);
 570		memcpy(v_rsp.sense, cmd->tvc_sense_buf,
 571		       se_cmd->scsi_sense_length);
 572
 573		iov_iter_init(&iov_iter, READ, &cmd->tvc_resp_iov,
 574			      cmd->tvc_in_iovs, sizeof(v_rsp));
 575		ret = copy_to_iter(&v_rsp, sizeof(v_rsp), &iov_iter);
 576		if (likely(ret == sizeof(v_rsp))) {
 577			struct vhost_scsi_virtqueue *q;
 578			vhost_add_used(cmd->tvc_vq, cmd->tvc_vq_desc, 0);
 579			q = container_of(cmd->tvc_vq, struct vhost_scsi_virtqueue, vq);
 580			vq = q - vs->vqs;
 581			__set_bit(vq, signal);
 582		} else
 583			pr_err("Faulted on virtio_scsi_cmd_resp\n");
 584
 585		vhost_scsi_release_cmd_res(se_cmd);
 586	}
 587
 588	vq = -1;
 589	while ((vq = find_next_bit(signal, VHOST_SCSI_MAX_VQ, vq + 1))
 590		< VHOST_SCSI_MAX_VQ)
 591		vhost_signal(&vs->dev, &vs->vqs[vq].vq);
 592}
 593
 594static struct vhost_scsi_cmd *
 595vhost_scsi_get_cmd(struct vhost_virtqueue *vq, struct vhost_scsi_tpg *tpg,
 596		   unsigned char *cdb, u64 scsi_tag, u16 lun, u8 task_attr,
 597		   u32 exp_data_len, int data_direction)
 598{
 599	struct vhost_scsi_virtqueue *svq = container_of(vq,
 600					struct vhost_scsi_virtqueue, vq);
 601	struct vhost_scsi_cmd *cmd;
 602	struct vhost_scsi_nexus *tv_nexus;
 603	struct scatterlist *sg, *prot_sg;
 604	struct page **pages;
 605	int tag;
 606
 607	tv_nexus = tpg->tpg_nexus;
 608	if (!tv_nexus) {
 609		pr_err("Unable to locate active struct vhost_scsi_nexus\n");
 610		return ERR_PTR(-EIO);
 611	}
 612
 613	tag = sbitmap_get(&svq->scsi_tags);
 614	if (tag < 0) {
 615		pr_err("Unable to obtain tag for vhost_scsi_cmd\n");
 616		return ERR_PTR(-ENOMEM);
 617	}
 618
 619	cmd = &svq->scsi_cmds[tag];
 620	sg = cmd->tvc_sgl;
 621	prot_sg = cmd->tvc_prot_sgl;
 622	pages = cmd->tvc_upages;
 623	memset(cmd, 0, sizeof(*cmd));
 624	cmd->tvc_sgl = sg;
 625	cmd->tvc_prot_sgl = prot_sg;
 626	cmd->tvc_upages = pages;
 627	cmd->tvc_se_cmd.map_tag = tag;
 628	cmd->tvc_tag = scsi_tag;
 629	cmd->tvc_lun = lun;
 630	cmd->tvc_task_attr = task_attr;
 631	cmd->tvc_exp_data_len = exp_data_len;
 632	cmd->tvc_data_direction = data_direction;
 633	cmd->tvc_nexus = tv_nexus;
 634	cmd->inflight = vhost_scsi_get_inflight(vq);
 635
 636	memcpy(cmd->tvc_cdb, cdb, VHOST_SCSI_MAX_CDB_SIZE);
 637
 638	return cmd;
 639}
 640
 641/*
 642 * Map a user memory range into a scatterlist
 643 *
 644 * Returns the number of scatterlist entries used or -errno on error.
 645 */
 646static int
 647vhost_scsi_map_to_sgl(struct vhost_scsi_cmd *cmd,
 648		      struct iov_iter *iter,
 649		      struct scatterlist *sgl,
 650		      bool write)
 651{
 652	struct page **pages = cmd->tvc_upages;
 653	struct scatterlist *sg = sgl;
 654	ssize_t bytes;
 655	size_t offset;
 656	unsigned int npages = 0;
 657
 658	bytes = iov_iter_get_pages(iter, pages, LONG_MAX,
 659				VHOST_SCSI_PREALLOC_UPAGES, &offset);
 660	/* No pages were pinned */
 661	if (bytes <= 0)
 662		return bytes < 0 ? bytes : -EFAULT;
 663
 664	iov_iter_advance(iter, bytes);
 665
 666	while (bytes) {
 667		unsigned n = min_t(unsigned, PAGE_SIZE - offset, bytes);
 668		sg_set_page(sg++, pages[npages++], n, offset);
 669		bytes -= n;
 670		offset = 0;
 671	}
 672	return npages;
 673}
 674
 675static int
 676vhost_scsi_calc_sgls(struct iov_iter *iter, size_t bytes, int max_sgls)
 677{
 678	int sgl_count = 0;
 679
 680	if (!iter || !iter->iov) {
 681		pr_err("%s: iter->iov is NULL, but expected bytes: %zu"
 682		       " present\n", __func__, bytes);
 683		return -EINVAL;
 684	}
 685
 686	sgl_count = iov_iter_npages(iter, 0xffff);
 687	if (sgl_count > max_sgls) {
 688		pr_err("%s: requested sgl_count: %d exceeds pre-allocated"
 689		       " max_sgls: %d\n", __func__, sgl_count, max_sgls);
 690		return -EINVAL;
 691	}
 692	return sgl_count;
 693}
 694
 695static int
 696vhost_scsi_iov_to_sgl(struct vhost_scsi_cmd *cmd, bool write,
 697		      struct iov_iter *iter,
 698		      struct scatterlist *sg, int sg_count)
 699{
 700	struct scatterlist *p = sg;
 701	int ret;
 702
 703	while (iov_iter_count(iter)) {
 704		ret = vhost_scsi_map_to_sgl(cmd, iter, sg, write);
 705		if (ret < 0) {
 706			while (p < sg) {
 707				struct page *page = sg_page(p++);
 708				if (page)
 709					put_page(page);
 710			}
 711			return ret;
 712		}
 713		sg += ret;
 714	}
 715	return 0;
 716}
 717
 718static int
 719vhost_scsi_mapal(struct vhost_scsi_cmd *cmd,
 720		 size_t prot_bytes, struct iov_iter *prot_iter,
 721		 size_t data_bytes, struct iov_iter *data_iter)
 722{
 723	int sgl_count, ret;
 724	bool write = (cmd->tvc_data_direction == DMA_FROM_DEVICE);
 725
 726	if (prot_bytes) {
 727		sgl_count = vhost_scsi_calc_sgls(prot_iter, prot_bytes,
 728						 VHOST_SCSI_PREALLOC_PROT_SGLS);
 729		if (sgl_count < 0)
 730			return sgl_count;
 731
 732		sg_init_table(cmd->tvc_prot_sgl, sgl_count);
 733		cmd->tvc_prot_sgl_count = sgl_count;
 734		pr_debug("%s prot_sg %p prot_sgl_count %u\n", __func__,
 735			 cmd->tvc_prot_sgl, cmd->tvc_prot_sgl_count);
 736
 737		ret = vhost_scsi_iov_to_sgl(cmd, write, prot_iter,
 738					    cmd->tvc_prot_sgl,
 739					    cmd->tvc_prot_sgl_count);
 740		if (ret < 0) {
 741			cmd->tvc_prot_sgl_count = 0;
 742			return ret;
 743		}
 744	}
 745	sgl_count = vhost_scsi_calc_sgls(data_iter, data_bytes,
 746					 VHOST_SCSI_PREALLOC_SGLS);
 747	if (sgl_count < 0)
 748		return sgl_count;
 749
 750	sg_init_table(cmd->tvc_sgl, sgl_count);
 751	cmd->tvc_sgl_count = sgl_count;
 752	pr_debug("%s data_sg %p data_sgl_count %u\n", __func__,
 753		  cmd->tvc_sgl, cmd->tvc_sgl_count);
 754
 755	ret = vhost_scsi_iov_to_sgl(cmd, write, data_iter,
 756				    cmd->tvc_sgl, cmd->tvc_sgl_count);
 757	if (ret < 0) {
 758		cmd->tvc_sgl_count = 0;
 759		return ret;
 760	}
 761	return 0;
 762}
 763
 764static int vhost_scsi_to_tcm_attr(int attr)
 765{
 766	switch (attr) {
 767	case VIRTIO_SCSI_S_SIMPLE:
 768		return TCM_SIMPLE_TAG;
 769	case VIRTIO_SCSI_S_ORDERED:
 770		return TCM_ORDERED_TAG;
 771	case VIRTIO_SCSI_S_HEAD:
 772		return TCM_HEAD_TAG;
 773	case VIRTIO_SCSI_S_ACA:
 774		return TCM_ACA_TAG;
 775	default:
 776		break;
 777	}
 778	return TCM_SIMPLE_TAG;
 779}
 780
 781static void vhost_scsi_target_queue_cmd(struct vhost_scsi_cmd *cmd)
 782{
 783	struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
 784	struct vhost_scsi_nexus *tv_nexus;
 785	struct scatterlist *sg_ptr, *sg_prot_ptr = NULL;
 786
 787	/* FIXME: BIDI operation */
 788	if (cmd->tvc_sgl_count) {
 789		sg_ptr = cmd->tvc_sgl;
 790
 791		if (cmd->tvc_prot_sgl_count)
 792			sg_prot_ptr = cmd->tvc_prot_sgl;
 793		else
 794			se_cmd->prot_pto = true;
 795	} else {
 796		sg_ptr = NULL;
 797	}
 798	tv_nexus = cmd->tvc_nexus;
 799
 800	se_cmd->tag = 0;
 801	target_init_cmd(se_cmd, tv_nexus->tvn_se_sess, &cmd->tvc_sense_buf[0],
 802			cmd->tvc_lun, cmd->tvc_exp_data_len,
 803			vhost_scsi_to_tcm_attr(cmd->tvc_task_attr),
 804			cmd->tvc_data_direction, TARGET_SCF_ACK_KREF);
 805
 806	if (target_submit_prep(se_cmd, cmd->tvc_cdb, sg_ptr,
 807			       cmd->tvc_sgl_count, NULL, 0, sg_prot_ptr,
 808			       cmd->tvc_prot_sgl_count, GFP_KERNEL))
 809		return;
 810
 811	target_queue_submission(se_cmd);
 812}
 813
 814static void
 815vhost_scsi_send_bad_target(struct vhost_scsi *vs,
 816			   struct vhost_virtqueue *vq,
 817			   int head, unsigned out)
 818{
 819	struct virtio_scsi_cmd_resp __user *resp;
 820	struct virtio_scsi_cmd_resp rsp;
 821	int ret;
 822
 823	memset(&rsp, 0, sizeof(rsp));
 824	rsp.response = VIRTIO_SCSI_S_BAD_TARGET;
 825	resp = vq->iov[out].iov_base;
 826	ret = __copy_to_user(resp, &rsp, sizeof(rsp));
 827	if (!ret)
 828		vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 829	else
 830		pr_err("Faulted on virtio_scsi_cmd_resp\n");
 831}
 832
 833static int
 834vhost_scsi_get_desc(struct vhost_scsi *vs, struct vhost_virtqueue *vq,
 835		    struct vhost_scsi_ctx *vc)
 836{
 837	int ret = -ENXIO;
 838
 839	vc->head = vhost_get_vq_desc(vq, vq->iov,
 840				     ARRAY_SIZE(vq->iov), &vc->out, &vc->in,
 841				     NULL, NULL);
 842
 843	pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n",
 844		 vc->head, vc->out, vc->in);
 845
 846	/* On error, stop handling until the next kick. */
 847	if (unlikely(vc->head < 0))
 848		goto done;
 849
 850	/* Nothing new?  Wait for eventfd to tell us they refilled. */
 851	if (vc->head == vq->num) {
 852		if (unlikely(vhost_enable_notify(&vs->dev, vq))) {
 853			vhost_disable_notify(&vs->dev, vq);
 854			ret = -EAGAIN;
 855		}
 856		goto done;
 857	}
 858
 859	/*
 860	 * Get the size of request and response buffers.
 861	 * FIXME: Not correct for BIDI operation
 862	 */
 863	vc->out_size = iov_length(vq->iov, vc->out);
 864	vc->in_size = iov_length(&vq->iov[vc->out], vc->in);
 865
 866	/*
 867	 * Copy over the virtio-scsi request header, which for a
 868	 * ANY_LAYOUT enabled guest may span multiple iovecs, or a
 869	 * single iovec may contain both the header + outgoing
 870	 * WRITE payloads.
 871	 *
 872	 * copy_from_iter() will advance out_iter, so that it will
 873	 * point at the start of the outgoing WRITE payload, if
 874	 * DMA_TO_DEVICE is set.
 875	 */
 876	iov_iter_init(&vc->out_iter, WRITE, vq->iov, vc->out, vc->out_size);
 877	ret = 0;
 878
 879done:
 880	return ret;
 881}
 882
 883static int
 884vhost_scsi_chk_size(struct vhost_virtqueue *vq, struct vhost_scsi_ctx *vc)
 885{
 886	if (unlikely(vc->in_size < vc->rsp_size)) {
 887		vq_err(vq,
 888		       "Response buf too small, need min %zu bytes got %zu",
 889		       vc->rsp_size, vc->in_size);
 890		return -EINVAL;
 891	} else if (unlikely(vc->out_size < vc->req_size)) {
 892		vq_err(vq,
 893		       "Request buf too small, need min %zu bytes got %zu",
 894		       vc->req_size, vc->out_size);
 895		return -EIO;
 896	}
 897
 898	return 0;
 899}
 900
 901static int
 902vhost_scsi_get_req(struct vhost_virtqueue *vq, struct vhost_scsi_ctx *vc,
 903		   struct vhost_scsi_tpg **tpgp)
 904{
 905	int ret = -EIO;
 906
 907	if (unlikely(!copy_from_iter_full(vc->req, vc->req_size,
 908					  &vc->out_iter))) {
 909		vq_err(vq, "Faulted on copy_from_iter_full\n");
 910	} else if (unlikely(*vc->lunp != 1)) {
 911		/* virtio-scsi spec requires byte 0 of the lun to be 1 */
 912		vq_err(vq, "Illegal virtio-scsi lun: %u\n", *vc->lunp);
 913	} else {
 914		struct vhost_scsi_tpg **vs_tpg, *tpg;
 915
 916		vs_tpg = vhost_vq_get_backend(vq);	/* validated at handler entry */
 917
 918		tpg = READ_ONCE(vs_tpg[*vc->target]);
 919		if (unlikely(!tpg)) {
 920			vq_err(vq, "Target 0x%x does not exist\n", *vc->target);
 921		} else {
 922			if (tpgp)
 923				*tpgp = tpg;
 924			ret = 0;
 925		}
 926	}
 927
 928	return ret;
 929}
 930
 931static u16 vhost_buf_to_lun(u8 *lun_buf)
 932{
 933	return ((lun_buf[2] << 8) | lun_buf[3]) & 0x3FFF;
 934}
 935
 936static void
 937vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
 938{
 939	struct vhost_scsi_tpg **vs_tpg, *tpg;
 940	struct virtio_scsi_cmd_req v_req;
 941	struct virtio_scsi_cmd_req_pi v_req_pi;
 942	struct vhost_scsi_ctx vc;
 943	struct vhost_scsi_cmd *cmd;
 944	struct iov_iter in_iter, prot_iter, data_iter;
 945	u64 tag;
 946	u32 exp_data_len, data_direction;
 947	int ret, prot_bytes, c = 0;
 948	u16 lun;
 949	u8 task_attr;
 950	bool t10_pi = vhost_has_feature(vq, VIRTIO_SCSI_F_T10_PI);
 951	void *cdb;
 952
 953	mutex_lock(&vq->mutex);
 954	/*
 955	 * We can handle the vq only after the endpoint is setup by calling the
 956	 * VHOST_SCSI_SET_ENDPOINT ioctl.
 957	 */
 958	vs_tpg = vhost_vq_get_backend(vq);
 959	if (!vs_tpg)
 960		goto out;
 961
 962	memset(&vc, 0, sizeof(vc));
 963	vc.rsp_size = sizeof(struct virtio_scsi_cmd_resp);
 964
 965	vhost_disable_notify(&vs->dev, vq);
 966
 967	do {
 968		ret = vhost_scsi_get_desc(vs, vq, &vc);
 969		if (ret)
 970			goto err;
 971
 972		/*
 973		 * Setup pointers and values based upon different virtio-scsi
 974		 * request header if T10_PI is enabled in KVM guest.
 975		 */
 976		if (t10_pi) {
 977			vc.req = &v_req_pi;
 978			vc.req_size = sizeof(v_req_pi);
 979			vc.lunp = &v_req_pi.lun[0];
 980			vc.target = &v_req_pi.lun[1];
 981		} else {
 982			vc.req = &v_req;
 983			vc.req_size = sizeof(v_req);
 984			vc.lunp = &v_req.lun[0];
 985			vc.target = &v_req.lun[1];
 986		}
 987
 988		/*
 989		 * Validate the size of request and response buffers.
 990		 * Check for a sane response buffer so we can report
 991		 * early errors back to the guest.
 992		 */
 993		ret = vhost_scsi_chk_size(vq, &vc);
 994		if (ret)
 995			goto err;
 996
 997		ret = vhost_scsi_get_req(vq, &vc, &tpg);
 998		if (ret)
 999			goto err;
1000
1001		ret = -EIO;	/* bad target on any error from here on */
1002
1003		/*
1004		 * Determine data_direction by calculating the total outgoing
1005		 * iovec sizes + incoming iovec sizes vs. virtio-scsi request +
1006		 * response headers respectively.
1007		 *
1008		 * For DMA_TO_DEVICE this is out_iter, which is already pointing
1009		 * to the right place.
1010		 *
1011		 * For DMA_FROM_DEVICE, the iovec will be just past the end
1012		 * of the virtio-scsi response header in either the same
1013		 * or immediately following iovec.
1014		 *
1015		 * Any associated T10_PI bytes for the outgoing / incoming
1016		 * payloads are included in calculation of exp_data_len here.
1017		 */
1018		prot_bytes = 0;
1019
1020		if (vc.out_size > vc.req_size) {
1021			data_direction = DMA_TO_DEVICE;
1022			exp_data_len = vc.out_size - vc.req_size;
1023			data_iter = vc.out_iter;
1024		} else if (vc.in_size > vc.rsp_size) {
1025			data_direction = DMA_FROM_DEVICE;
1026			exp_data_len = vc.in_size - vc.rsp_size;
1027
1028			iov_iter_init(&in_iter, READ, &vq->iov[vc.out], vc.in,
1029				      vc.rsp_size + exp_data_len);
1030			iov_iter_advance(&in_iter, vc.rsp_size);
1031			data_iter = in_iter;
1032		} else {
1033			data_direction = DMA_NONE;
1034			exp_data_len = 0;
1035		}
1036		/*
1037		 * If T10_PI header + payload is present, setup prot_iter values
1038		 * and recalculate data_iter for vhost_scsi_mapal() mapping to
1039		 * host scatterlists via get_user_pages_fast().
1040		 */
1041		if (t10_pi) {
1042			if (v_req_pi.pi_bytesout) {
1043				if (data_direction != DMA_TO_DEVICE) {
1044					vq_err(vq, "Received non zero pi_bytesout,"
1045						" but wrong data_direction\n");
1046					goto err;
1047				}
1048				prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesout);
1049			} else if (v_req_pi.pi_bytesin) {
1050				if (data_direction != DMA_FROM_DEVICE) {
1051					vq_err(vq, "Received non zero pi_bytesin,"
1052						" but wrong data_direction\n");
1053					goto err;
1054				}
1055				prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesin);
1056			}
1057			/*
1058			 * Set prot_iter to data_iter and truncate it to
1059			 * prot_bytes, and advance data_iter past any
1060			 * preceeding prot_bytes that may be present.
1061			 *
1062			 * Also fix up the exp_data_len to reflect only the
1063			 * actual data payload length.
1064			 */
1065			if (prot_bytes) {
1066				exp_data_len -= prot_bytes;
1067				prot_iter = data_iter;
1068				iov_iter_truncate(&prot_iter, prot_bytes);
1069				iov_iter_advance(&data_iter, prot_bytes);
1070			}
1071			tag = vhost64_to_cpu(vq, v_req_pi.tag);
1072			task_attr = v_req_pi.task_attr;
1073			cdb = &v_req_pi.cdb[0];
1074			lun = vhost_buf_to_lun(v_req_pi.lun);
1075		} else {
1076			tag = vhost64_to_cpu(vq, v_req.tag);
1077			task_attr = v_req.task_attr;
1078			cdb = &v_req.cdb[0];
1079			lun = vhost_buf_to_lun(v_req.lun);
1080		}
1081		/*
1082		 * Check that the received CDB size does not exceeded our
1083		 * hardcoded max for vhost-scsi, then get a pre-allocated
1084		 * cmd descriptor for the new virtio-scsi tag.
1085		 *
1086		 * TODO what if cdb was too small for varlen cdb header?
1087		 */
1088		if (unlikely(scsi_command_size(cdb) > VHOST_SCSI_MAX_CDB_SIZE)) {
1089			vq_err(vq, "Received SCSI CDB with command_size: %d that"
1090				" exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1091				scsi_command_size(cdb), VHOST_SCSI_MAX_CDB_SIZE);
1092				goto err;
1093		}
1094		cmd = vhost_scsi_get_cmd(vq, tpg, cdb, tag, lun, task_attr,
1095					 exp_data_len + prot_bytes,
1096					 data_direction);
1097		if (IS_ERR(cmd)) {
1098			vq_err(vq, "vhost_scsi_get_cmd failed %ld\n",
1099			       PTR_ERR(cmd));
1100			goto err;
1101		}
1102		cmd->tvc_vhost = vs;
1103		cmd->tvc_vq = vq;
1104		cmd->tvc_resp_iov = vq->iov[vc.out];
1105		cmd->tvc_in_iovs = vc.in;
1106
1107		pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n",
1108			 cmd->tvc_cdb[0], cmd->tvc_lun);
1109		pr_debug("cmd: %p exp_data_len: %d, prot_bytes: %d data_direction:"
1110			 " %d\n", cmd, exp_data_len, prot_bytes, data_direction);
1111
1112		if (data_direction != DMA_NONE) {
1113			if (unlikely(vhost_scsi_mapal(cmd, prot_bytes,
1114						      &prot_iter, exp_data_len,
1115						      &data_iter))) {
1116				vq_err(vq, "Failed to map iov to sgl\n");
1117				vhost_scsi_release_cmd_res(&cmd->tvc_se_cmd);
1118				goto err;
1119			}
1120		}
1121		/*
1122		 * Save the descriptor from vhost_get_vq_desc() to be used to
1123		 * complete the virtio-scsi request in TCM callback context via
1124		 * vhost_scsi_queue_data_in() and vhost_scsi_queue_status()
1125		 */
1126		cmd->tvc_vq_desc = vc.head;
1127		vhost_scsi_target_queue_cmd(cmd);
1128		ret = 0;
1129err:
1130		/*
1131		 * ENXIO:  No more requests, or read error, wait for next kick
1132		 * EINVAL: Invalid response buffer, drop the request
1133		 * EIO:    Respond with bad target
1134		 * EAGAIN: Pending request
1135		 */
1136		if (ret == -ENXIO)
1137			break;
1138		else if (ret == -EIO)
1139			vhost_scsi_send_bad_target(vs, vq, vc.head, vc.out);
1140	} while (likely(!vhost_exceeds_weight(vq, ++c, 0)));
1141out:
1142	mutex_unlock(&vq->mutex);
1143}
1144
1145static void
1146vhost_scsi_send_tmf_resp(struct vhost_scsi *vs, struct vhost_virtqueue *vq,
1147			 int in_iovs, int vq_desc, struct iovec *resp_iov,
1148			 int tmf_resp_code)
1149{
1150	struct virtio_scsi_ctrl_tmf_resp rsp;
1151	struct iov_iter iov_iter;
1152	int ret;
1153
1154	pr_debug("%s\n", __func__);
1155	memset(&rsp, 0, sizeof(rsp));
1156	rsp.response = tmf_resp_code;
1157
1158	iov_iter_init(&iov_iter, READ, resp_iov, in_iovs, sizeof(rsp));
1159
1160	ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter);
1161	if (likely(ret == sizeof(rsp)))
1162		vhost_add_used_and_signal(&vs->dev, vq, vq_desc, 0);
1163	else
1164		pr_err("Faulted on virtio_scsi_ctrl_tmf_resp\n");
1165}
1166
1167static void vhost_scsi_tmf_resp_work(struct vhost_work *work)
1168{
1169	struct vhost_scsi_tmf *tmf = container_of(work, struct vhost_scsi_tmf,
1170						  vwork);
1171	int resp_code;
1172
1173	if (tmf->scsi_resp == TMR_FUNCTION_COMPLETE)
1174		resp_code = VIRTIO_SCSI_S_FUNCTION_SUCCEEDED;
1175	else
1176		resp_code = VIRTIO_SCSI_S_FUNCTION_REJECTED;
1177
1178	vhost_scsi_send_tmf_resp(tmf->vhost, &tmf->svq->vq, tmf->in_iovs,
1179				 tmf->vq_desc, &tmf->resp_iov, resp_code);
1180	vhost_scsi_release_tmf_res(tmf);
1181}
1182
1183static void
1184vhost_scsi_handle_tmf(struct vhost_scsi *vs, struct vhost_scsi_tpg *tpg,
1185		      struct vhost_virtqueue *vq,
1186		      struct virtio_scsi_ctrl_tmf_req *vtmf,
1187		      struct vhost_scsi_ctx *vc)
1188{
1189	struct vhost_scsi_virtqueue *svq = container_of(vq,
1190					struct vhost_scsi_virtqueue, vq);
1191	struct vhost_scsi_tmf *tmf;
1192
1193	if (vhost32_to_cpu(vq, vtmf->subtype) !=
1194	    VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET)
1195		goto send_reject;
1196
1197	if (!tpg->tpg_nexus || !tpg->tpg_nexus->tvn_se_sess) {
1198		pr_err("Unable to locate active struct vhost_scsi_nexus for LUN RESET.\n");
1199		goto send_reject;
1200	}
1201
1202	mutex_lock(&tpg->tv_tpg_mutex);
1203	if (list_empty(&tpg->tmf_queue)) {
1204		pr_err("Missing reserve TMF. Could not handle LUN RESET.\n");
1205		mutex_unlock(&tpg->tv_tpg_mutex);
1206		goto send_reject;
1207	}
1208
1209	tmf = list_first_entry(&tpg->tmf_queue, struct vhost_scsi_tmf,
1210			       queue_entry);
1211	list_del_init(&tmf->queue_entry);
1212	mutex_unlock(&tpg->tv_tpg_mutex);
1213
1214	tmf->tpg = tpg;
1215	tmf->vhost = vs;
1216	tmf->svq = svq;
1217	tmf->resp_iov = vq->iov[vc->out];
1218	tmf->vq_desc = vc->head;
1219	tmf->in_iovs = vc->in;
1220	tmf->inflight = vhost_scsi_get_inflight(vq);
1221
1222	if (target_submit_tmr(&tmf->se_cmd, tpg->tpg_nexus->tvn_se_sess, NULL,
1223			      vhost_buf_to_lun(vtmf->lun), NULL,
1224			      TMR_LUN_RESET, GFP_KERNEL, 0,
1225			      TARGET_SCF_ACK_KREF) < 0) {
1226		vhost_scsi_release_tmf_res(tmf);
1227		goto send_reject;
1228	}
1229
1230	return;
1231
1232send_reject:
1233	vhost_scsi_send_tmf_resp(vs, vq, vc->in, vc->head, &vq->iov[vc->out],
1234				 VIRTIO_SCSI_S_FUNCTION_REJECTED);
1235}
1236
1237static void
1238vhost_scsi_send_an_resp(struct vhost_scsi *vs,
1239			struct vhost_virtqueue *vq,
1240			struct vhost_scsi_ctx *vc)
1241{
1242	struct virtio_scsi_ctrl_an_resp rsp;
1243	struct iov_iter iov_iter;
1244	int ret;
1245
1246	pr_debug("%s\n", __func__);
1247	memset(&rsp, 0, sizeof(rsp));	/* event_actual = 0 */
1248	rsp.response = VIRTIO_SCSI_S_OK;
1249
1250	iov_iter_init(&iov_iter, READ, &vq->iov[vc->out], vc->in, sizeof(rsp));
1251
1252	ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter);
1253	if (likely(ret == sizeof(rsp)))
1254		vhost_add_used_and_signal(&vs->dev, vq, vc->head, 0);
1255	else
1256		pr_err("Faulted on virtio_scsi_ctrl_an_resp\n");
1257}
1258
1259static void
1260vhost_scsi_ctl_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
1261{
1262	struct vhost_scsi_tpg *tpg;
1263	union {
1264		__virtio32 type;
1265		struct virtio_scsi_ctrl_an_req an;
1266		struct virtio_scsi_ctrl_tmf_req tmf;
1267	} v_req;
1268	struct vhost_scsi_ctx vc;
1269	size_t typ_size;
1270	int ret, c = 0;
1271
1272	mutex_lock(&vq->mutex);
1273	/*
1274	 * We can handle the vq only after the endpoint is setup by calling the
1275	 * VHOST_SCSI_SET_ENDPOINT ioctl.
1276	 */
1277	if (!vhost_vq_get_backend(vq))
1278		goto out;
1279
1280	memset(&vc, 0, sizeof(vc));
1281
1282	vhost_disable_notify(&vs->dev, vq);
1283
1284	do {
1285		ret = vhost_scsi_get_desc(vs, vq, &vc);
1286		if (ret)
1287			goto err;
1288
1289		/*
1290		 * Get the request type first in order to setup
1291		 * other parameters dependent on the type.
1292		 */
1293		vc.req = &v_req.type;
1294		typ_size = sizeof(v_req.type);
1295
1296		if (unlikely(!copy_from_iter_full(vc.req, typ_size,
1297						  &vc.out_iter))) {
1298			vq_err(vq, "Faulted on copy_from_iter tmf type\n");
1299			/*
1300			 * The size of the response buffer depends on the
1301			 * request type and must be validated against it.
1302			 * Since the request type is not known, don't send
1303			 * a response.
1304			 */
1305			continue;
1306		}
1307
1308		switch (vhost32_to_cpu(vq, v_req.type)) {
1309		case VIRTIO_SCSI_T_TMF:
1310			vc.req = &v_req.tmf;
1311			vc.req_size = sizeof(struct virtio_scsi_ctrl_tmf_req);
1312			vc.rsp_size = sizeof(struct virtio_scsi_ctrl_tmf_resp);
1313			vc.lunp = &v_req.tmf.lun[0];
1314			vc.target = &v_req.tmf.lun[1];
1315			break;
1316		case VIRTIO_SCSI_T_AN_QUERY:
1317		case VIRTIO_SCSI_T_AN_SUBSCRIBE:
1318			vc.req = &v_req.an;
1319			vc.req_size = sizeof(struct virtio_scsi_ctrl_an_req);
1320			vc.rsp_size = sizeof(struct virtio_scsi_ctrl_an_resp);
1321			vc.lunp = &v_req.an.lun[0];
1322			vc.target = NULL;
1323			break;
1324		default:
1325			vq_err(vq, "Unknown control request %d", v_req.type);
1326			continue;
1327		}
1328
1329		/*
1330		 * Validate the size of request and response buffers.
1331		 * Check for a sane response buffer so we can report
1332		 * early errors back to the guest.
1333		 */
1334		ret = vhost_scsi_chk_size(vq, &vc);
1335		if (ret)
1336			goto err;
1337
1338		/*
1339		 * Get the rest of the request now that its size is known.
1340		 */
1341		vc.req += typ_size;
1342		vc.req_size -= typ_size;
1343
1344		ret = vhost_scsi_get_req(vq, &vc, &tpg);
1345		if (ret)
1346			goto err;
1347
1348		if (v_req.type == VIRTIO_SCSI_T_TMF)
1349			vhost_scsi_handle_tmf(vs, tpg, vq, &v_req.tmf, &vc);
1350		else
1351			vhost_scsi_send_an_resp(vs, vq, &vc);
1352err:
1353		/*
1354		 * ENXIO:  No more requests, or read error, wait for next kick
1355		 * EINVAL: Invalid response buffer, drop the request
1356		 * EIO:    Respond with bad target
1357		 * EAGAIN: Pending request
1358		 */
1359		if (ret == -ENXIO)
1360			break;
1361		else if (ret == -EIO)
1362			vhost_scsi_send_bad_target(vs, vq, vc.head, vc.out);
1363	} while (likely(!vhost_exceeds_weight(vq, ++c, 0)));
1364out:
1365	mutex_unlock(&vq->mutex);
1366}
1367
1368static void vhost_scsi_ctl_handle_kick(struct vhost_work *work)
1369{
1370	struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1371						poll.work);
1372	struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1373
1374	pr_debug("%s: The handling func for control queue.\n", __func__);
1375	vhost_scsi_ctl_handle_vq(vs, vq);
1376}
1377
1378static void
1379vhost_scsi_send_evt(struct vhost_scsi *vs,
1380		   struct vhost_scsi_tpg *tpg,
1381		   struct se_lun *lun,
1382		   u32 event,
1383		   u32 reason)
1384{
1385	struct vhost_scsi_evt *evt;
1386
1387	evt = vhost_scsi_allocate_evt(vs, event, reason);
1388	if (!evt)
1389		return;
1390
1391	if (tpg && lun) {
1392		/* TODO: share lun setup code with virtio-scsi.ko */
1393		/*
1394		 * Note: evt->event is zeroed when we allocate it and
1395		 * lun[4-7] need to be zero according to virtio-scsi spec.
1396		 */
1397		evt->event.lun[0] = 0x01;
1398		evt->event.lun[1] = tpg->tport_tpgt;
1399		if (lun->unpacked_lun >= 256)
1400			evt->event.lun[2] = lun->unpacked_lun >> 8 | 0x40 ;
1401		evt->event.lun[3] = lun->unpacked_lun & 0xFF;
1402	}
1403
1404	llist_add(&evt->list, &vs->vs_event_list);
1405	vhost_work_queue(&vs->dev, &vs->vs_event_work);
1406}
1407
1408static void vhost_scsi_evt_handle_kick(struct vhost_work *work)
1409{
1410	struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1411						poll.work);
1412	struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1413
1414	mutex_lock(&vq->mutex);
1415	if (!vhost_vq_get_backend(vq))
1416		goto out;
1417
1418	if (vs->vs_events_missed)
1419		vhost_scsi_send_evt(vs, NULL, NULL, VIRTIO_SCSI_T_NO_EVENT, 0);
1420out:
1421	mutex_unlock(&vq->mutex);
1422}
1423
1424static void vhost_scsi_handle_kick(struct vhost_work *work)
1425{
1426	struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1427						poll.work);
1428	struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1429
1430	vhost_scsi_handle_vq(vs, vq);
1431}
1432
1433/* Callers must hold dev mutex */
1434static void vhost_scsi_flush(struct vhost_scsi *vs)
1435{
1436	struct vhost_scsi_inflight *old_inflight[VHOST_SCSI_MAX_VQ];
1437	int i;
1438
1439	/* Init new inflight and remember the old inflight */
1440	vhost_scsi_init_inflight(vs, old_inflight);
1441
1442	/*
1443	 * The inflight->kref was initialized to 1. We decrement it here to
1444	 * indicate the start of the flush operation so that it will reach 0
1445	 * when all the reqs are finished.
1446	 */
1447	for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1448		kref_put(&old_inflight[i]->kref, vhost_scsi_done_inflight);
1449
1450	/* Flush both the vhost poll and vhost work */
1451	vhost_work_dev_flush(&vs->dev);
1452
1453	/* Wait for all reqs issued before the flush to be finished */
1454	for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1455		wait_for_completion(&old_inflight[i]->comp);
1456}
1457
1458static void vhost_scsi_destroy_vq_cmds(struct vhost_virtqueue *vq)
1459{
1460	struct vhost_scsi_virtqueue *svq = container_of(vq,
1461					struct vhost_scsi_virtqueue, vq);
1462	struct vhost_scsi_cmd *tv_cmd;
1463	unsigned int i;
1464
1465	if (!svq->scsi_cmds)
1466		return;
1467
1468	for (i = 0; i < svq->max_cmds; i++) {
1469		tv_cmd = &svq->scsi_cmds[i];
1470
1471		kfree(tv_cmd->tvc_sgl);
1472		kfree(tv_cmd->tvc_prot_sgl);
1473		kfree(tv_cmd->tvc_upages);
1474	}
1475
1476	sbitmap_free(&svq->scsi_tags);
1477	kfree(svq->scsi_cmds);
1478	svq->scsi_cmds = NULL;
1479}
1480
1481static int vhost_scsi_setup_vq_cmds(struct vhost_virtqueue *vq, int max_cmds)
1482{
1483	struct vhost_scsi_virtqueue *svq = container_of(vq,
1484					struct vhost_scsi_virtqueue, vq);
1485	struct vhost_scsi_cmd *tv_cmd;
1486	unsigned int i;
1487
1488	if (svq->scsi_cmds)
1489		return 0;
1490
1491	if (sbitmap_init_node(&svq->scsi_tags, max_cmds, -1, GFP_KERNEL,
1492			      NUMA_NO_NODE, false, true))
1493		return -ENOMEM;
1494	svq->max_cmds = max_cmds;
1495
1496	svq->scsi_cmds = kcalloc(max_cmds, sizeof(*tv_cmd), GFP_KERNEL);
1497	if (!svq->scsi_cmds) {
1498		sbitmap_free(&svq->scsi_tags);
1499		return -ENOMEM;
1500	}
1501
1502	for (i = 0; i < max_cmds; i++) {
1503		tv_cmd = &svq->scsi_cmds[i];
1504
1505		tv_cmd->tvc_sgl = kcalloc(VHOST_SCSI_PREALLOC_SGLS,
1506					  sizeof(struct scatterlist),
1507					  GFP_KERNEL);
1508		if (!tv_cmd->tvc_sgl) {
1509			pr_err("Unable to allocate tv_cmd->tvc_sgl\n");
1510			goto out;
1511		}
1512
1513		tv_cmd->tvc_upages = kcalloc(VHOST_SCSI_PREALLOC_UPAGES,
1514					     sizeof(struct page *),
1515					     GFP_KERNEL);
1516		if (!tv_cmd->tvc_upages) {
1517			pr_err("Unable to allocate tv_cmd->tvc_upages\n");
1518			goto out;
1519		}
1520
1521		tv_cmd->tvc_prot_sgl = kcalloc(VHOST_SCSI_PREALLOC_PROT_SGLS,
1522					       sizeof(struct scatterlist),
1523					       GFP_KERNEL);
1524		if (!tv_cmd->tvc_prot_sgl) {
1525			pr_err("Unable to allocate tv_cmd->tvc_prot_sgl\n");
1526			goto out;
1527		}
1528	}
1529	return 0;
1530out:
1531	vhost_scsi_destroy_vq_cmds(vq);
1532	return -ENOMEM;
1533}
1534
1535/*
1536 * Called from vhost_scsi_ioctl() context to walk the list of available
1537 * vhost_scsi_tpg with an active struct vhost_scsi_nexus
1538 *
1539 *  The lock nesting rule is:
1540 *    vhost_scsi_mutex -> vs->dev.mutex -> tpg->tv_tpg_mutex -> vq->mutex
1541 */
1542static int
1543vhost_scsi_set_endpoint(struct vhost_scsi *vs,
1544			struct vhost_scsi_target *t)
1545{
1546	struct se_portal_group *se_tpg;
1547	struct vhost_scsi_tport *tv_tport;
1548	struct vhost_scsi_tpg *tpg;
1549	struct vhost_scsi_tpg **vs_tpg;
1550	struct vhost_virtqueue *vq;
1551	int index, ret, i, len;
1552	bool match = false;
1553
1554	mutex_lock(&vhost_scsi_mutex);
1555	mutex_lock(&vs->dev.mutex);
1556
1557	/* Verify that ring has been setup correctly. */
1558	for (index = 0; index < vs->dev.nvqs; ++index) {
1559		/* Verify that ring has been setup correctly. */
1560		if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1561			ret = -EFAULT;
1562			goto out;
1563		}
1564	}
1565
1566	len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET;
1567	vs_tpg = kzalloc(len, GFP_KERNEL);
1568	if (!vs_tpg) {
1569		ret = -ENOMEM;
1570		goto out;
1571	}
1572	if (vs->vs_tpg)
1573		memcpy(vs_tpg, vs->vs_tpg, len);
1574
1575	list_for_each_entry(tpg, &vhost_scsi_list, tv_tpg_list) {
1576		mutex_lock(&tpg->tv_tpg_mutex);
1577		if (!tpg->tpg_nexus) {
1578			mutex_unlock(&tpg->tv_tpg_mutex);
1579			continue;
1580		}
1581		if (tpg->tv_tpg_vhost_count != 0) {
1582			mutex_unlock(&tpg->tv_tpg_mutex);
1583			continue;
1584		}
1585		tv_tport = tpg->tport;
1586
1587		if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1588			if (vs->vs_tpg && vs->vs_tpg[tpg->tport_tpgt]) {
1589				mutex_unlock(&tpg->tv_tpg_mutex);
1590				ret = -EEXIST;
1591				goto undepend;
1592			}
1593			/*
1594			 * In order to ensure individual vhost-scsi configfs
1595			 * groups cannot be removed while in use by vhost ioctl,
1596			 * go ahead and take an explicit se_tpg->tpg_group.cg_item
1597			 * dependency now.
1598			 */
1599			se_tpg = &tpg->se_tpg;
1600			ret = target_depend_item(&se_tpg->tpg_group.cg_item);
1601			if (ret) {
1602				pr_warn("target_depend_item() failed: %d\n", ret);
1603				mutex_unlock(&tpg->tv_tpg_mutex);
1604				goto undepend;
1605			}
1606			tpg->tv_tpg_vhost_count++;
1607			tpg->vhost_scsi = vs;
1608			vs_tpg[tpg->tport_tpgt] = tpg;
1609			match = true;
1610		}
1611		mutex_unlock(&tpg->tv_tpg_mutex);
1612	}
1613
1614	if (match) {
1615		memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
1616		       sizeof(vs->vs_vhost_wwpn));
1617
1618		for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++) {
1619			vq = &vs->vqs[i].vq;
1620			if (!vhost_vq_is_setup(vq))
1621				continue;
1622
1623			ret = vhost_scsi_setup_vq_cmds(vq, vq->num);
1624			if (ret)
1625				goto destroy_vq_cmds;
1626		}
1627
1628		for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1629			vq = &vs->vqs[i].vq;
1630			mutex_lock(&vq->mutex);
1631			vhost_vq_set_backend(vq, vs_tpg);
1632			vhost_vq_init_access(vq);
1633			mutex_unlock(&vq->mutex);
1634		}
1635		ret = 0;
1636	} else {
1637		ret = -EEXIST;
1638	}
1639
1640	/*
1641	 * Act as synchronize_rcu to make sure access to
1642	 * old vs->vs_tpg is finished.
1643	 */
1644	vhost_scsi_flush(vs);
1645	kfree(vs->vs_tpg);
1646	vs->vs_tpg = vs_tpg;
1647	goto out;
1648
1649destroy_vq_cmds:
1650	for (i--; i >= VHOST_SCSI_VQ_IO; i--) {
1651		if (!vhost_vq_get_backend(&vs->vqs[i].vq))
1652			vhost_scsi_destroy_vq_cmds(&vs->vqs[i].vq);
1653	}
1654undepend:
1655	for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1656		tpg = vs_tpg[i];
1657		if (tpg) {
1658			tpg->tv_tpg_vhost_count--;
1659			target_undepend_item(&tpg->se_tpg.tpg_group.cg_item);
1660		}
1661	}
1662	kfree(vs_tpg);
1663out:
1664	mutex_unlock(&vs->dev.mutex);
1665	mutex_unlock(&vhost_scsi_mutex);
1666	return ret;
1667}
1668
1669static int
1670vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
1671			  struct vhost_scsi_target *t)
1672{
1673	struct se_portal_group *se_tpg;
1674	struct vhost_scsi_tport *tv_tport;
1675	struct vhost_scsi_tpg *tpg;
1676	struct vhost_virtqueue *vq;
1677	bool match = false;
1678	int index, ret, i;
1679	u8 target;
1680
1681	mutex_lock(&vhost_scsi_mutex);
1682	mutex_lock(&vs->dev.mutex);
1683	/* Verify that ring has been setup correctly. */
1684	for (index = 0; index < vs->dev.nvqs; ++index) {
1685		if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1686			ret = -EFAULT;
1687			goto err_dev;
1688		}
1689	}
1690
1691	if (!vs->vs_tpg) {
1692		ret = 0;
1693		goto err_dev;
1694	}
1695
1696	for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1697		target = i;
1698		tpg = vs->vs_tpg[target];
1699		if (!tpg)
1700			continue;
1701
1702		mutex_lock(&tpg->tv_tpg_mutex);
1703		tv_tport = tpg->tport;
1704		if (!tv_tport) {
1705			ret = -ENODEV;
1706			goto err_tpg;
1707		}
1708
1709		if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1710			pr_warn("tv_tport->tport_name: %s, tpg->tport_tpgt: %hu"
1711				" does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
1712				tv_tport->tport_name, tpg->tport_tpgt,
1713				t->vhost_wwpn, t->vhost_tpgt);
1714			ret = -EINVAL;
1715			goto err_tpg;
1716		}
1717		tpg->tv_tpg_vhost_count--;
1718		tpg->vhost_scsi = NULL;
1719		vs->vs_tpg[target] = NULL;
1720		match = true;
1721		mutex_unlock(&tpg->tv_tpg_mutex);
1722		/*
1723		 * Release se_tpg->tpg_group.cg_item configfs dependency now
1724		 * to allow vhost-scsi WWPN se_tpg->tpg_group shutdown to occur.
1725		 */
1726		se_tpg = &tpg->se_tpg;
1727		target_undepend_item(&se_tpg->tpg_group.cg_item);
1728	}
1729	if (match) {
1730		for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1731			vq = &vs->vqs[i].vq;
1732			mutex_lock(&vq->mutex);
1733			vhost_vq_set_backend(vq, NULL);
1734			mutex_unlock(&vq->mutex);
1735		}
1736		/* Make sure cmds are not running before tearing them down. */
1737		vhost_scsi_flush(vs);
1738
1739		for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1740			vq = &vs->vqs[i].vq;
1741			vhost_scsi_destroy_vq_cmds(vq);
1742		}
1743	}
1744	/*
1745	 * Act as synchronize_rcu to make sure access to
1746	 * old vs->vs_tpg is finished.
1747	 */
1748	vhost_scsi_flush(vs);
1749	kfree(vs->vs_tpg);
1750	vs->vs_tpg = NULL;
1751	WARN_ON(vs->vs_events_nr);
1752	mutex_unlock(&vs->dev.mutex);
1753	mutex_unlock(&vhost_scsi_mutex);
1754	return 0;
1755
1756err_tpg:
1757	mutex_unlock(&tpg->tv_tpg_mutex);
1758err_dev:
1759	mutex_unlock(&vs->dev.mutex);
1760	mutex_unlock(&vhost_scsi_mutex);
1761	return ret;
1762}
1763
1764static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features)
1765{
1766	struct vhost_virtqueue *vq;
1767	int i;
1768
1769	if (features & ~VHOST_SCSI_FEATURES)
1770		return -EOPNOTSUPP;
1771
1772	mutex_lock(&vs->dev.mutex);
1773	if ((features & (1 << VHOST_F_LOG_ALL)) &&
1774	    !vhost_log_access_ok(&vs->dev)) {
1775		mutex_unlock(&vs->dev.mutex);
1776		return -EFAULT;
1777	}
1778
1779	for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1780		vq = &vs->vqs[i].vq;
1781		mutex_lock(&vq->mutex);
1782		vq->acked_features = features;
1783		mutex_unlock(&vq->mutex);
1784	}
1785	mutex_unlock(&vs->dev.mutex);
1786	return 0;
1787}
1788
1789static int vhost_scsi_open(struct inode *inode, struct file *f)
1790{
1791	struct vhost_scsi *vs;
1792	struct vhost_virtqueue **vqs;
1793	int r = -ENOMEM, i;
1794
1795	vs = kvzalloc(sizeof(*vs), GFP_KERNEL);
1796	if (!vs)
1797		goto err_vs;
1798
1799	vqs = kmalloc_array(VHOST_SCSI_MAX_VQ, sizeof(*vqs), GFP_KERNEL);
1800	if (!vqs)
1801		goto err_vqs;
1802
1803	vhost_work_init(&vs->vs_completion_work, vhost_scsi_complete_cmd_work);
1804	vhost_work_init(&vs->vs_event_work, vhost_scsi_evt_work);
1805
1806	vs->vs_events_nr = 0;
1807	vs->vs_events_missed = false;
1808
1809	vqs[VHOST_SCSI_VQ_CTL] = &vs->vqs[VHOST_SCSI_VQ_CTL].vq;
1810	vqs[VHOST_SCSI_VQ_EVT] = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1811	vs->vqs[VHOST_SCSI_VQ_CTL].vq.handle_kick = vhost_scsi_ctl_handle_kick;
1812	vs->vqs[VHOST_SCSI_VQ_EVT].vq.handle_kick = vhost_scsi_evt_handle_kick;
1813	for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++) {
1814		vqs[i] = &vs->vqs[i].vq;
1815		vs->vqs[i].vq.handle_kick = vhost_scsi_handle_kick;
1816	}
1817	vhost_dev_init(&vs->dev, vqs, VHOST_SCSI_MAX_VQ, UIO_MAXIOV,
1818		       VHOST_SCSI_WEIGHT, 0, true, NULL);
1819
1820	vhost_scsi_init_inflight(vs, NULL);
1821
1822	f->private_data = vs;
1823	return 0;
1824
1825err_vqs:
1826	kvfree(vs);
1827err_vs:
1828	return r;
1829}
1830
1831static int vhost_scsi_release(struct inode *inode, struct file *f)
1832{
1833	struct vhost_scsi *vs = f->private_data;
1834	struct vhost_scsi_target t;
1835
1836	mutex_lock(&vs->dev.mutex);
1837	memcpy(t.vhost_wwpn, vs->vs_vhost_wwpn, sizeof(t.vhost_wwpn));
1838	mutex_unlock(&vs->dev.mutex);
1839	vhost_scsi_clear_endpoint(vs, &t);
1840	vhost_dev_stop(&vs->dev);
1841	vhost_dev_cleanup(&vs->dev);
1842	/* Jobs can re-queue themselves in evt kick handler. Do extra flush. */
1843	vhost_scsi_flush(vs);
1844	kfree(vs->dev.vqs);
1845	kvfree(vs);
1846	return 0;
1847}
1848
1849static long
1850vhost_scsi_ioctl(struct file *f,
1851		 unsigned int ioctl,
1852		 unsigned long arg)
1853{
1854	struct vhost_scsi *vs = f->private_data;
1855	struct vhost_scsi_target backend;
1856	void __user *argp = (void __user *)arg;
1857	u64 __user *featurep = argp;
1858	u32 __user *eventsp = argp;
1859	u32 events_missed;
1860	u64 features;
1861	int r, abi_version = VHOST_SCSI_ABI_VERSION;
1862	struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1863
1864	switch (ioctl) {
1865	case VHOST_SCSI_SET_ENDPOINT:
1866		if (copy_from_user(&backend, argp, sizeof backend))
1867			return -EFAULT;
1868		if (backend.reserved != 0)
1869			return -EOPNOTSUPP;
1870
1871		return vhost_scsi_set_endpoint(vs, &backend);
1872	case VHOST_SCSI_CLEAR_ENDPOINT:
1873		if (copy_from_user(&backend, argp, sizeof backend))
1874			return -EFAULT;
1875		if (backend.reserved != 0)
1876			return -EOPNOTSUPP;
1877
1878		return vhost_scsi_clear_endpoint(vs, &backend);
1879	case VHOST_SCSI_GET_ABI_VERSION:
1880		if (copy_to_user(argp, &abi_version, sizeof abi_version))
1881			return -EFAULT;
1882		return 0;
1883	case VHOST_SCSI_SET_EVENTS_MISSED:
1884		if (get_user(events_missed, eventsp))
1885			return -EFAULT;
1886		mutex_lock(&vq->mutex);
1887		vs->vs_events_missed = events_missed;
1888		mutex_unlock(&vq->mutex);
1889		return 0;
1890	case VHOST_SCSI_GET_EVENTS_MISSED:
1891		mutex_lock(&vq->mutex);
1892		events_missed = vs->vs_events_missed;
1893		mutex_unlock(&vq->mutex);
1894		if (put_user(events_missed, eventsp))
1895			return -EFAULT;
1896		return 0;
1897	case VHOST_GET_FEATURES:
1898		features = VHOST_SCSI_FEATURES;
1899		if (copy_to_user(featurep, &features, sizeof features))
1900			return -EFAULT;
1901		return 0;
1902	case VHOST_SET_FEATURES:
1903		if (copy_from_user(&features, featurep, sizeof features))
1904			return -EFAULT;
1905		return vhost_scsi_set_features(vs, features);
1906	default:
1907		mutex_lock(&vs->dev.mutex);
1908		r = vhost_dev_ioctl(&vs->dev, ioctl, argp);
1909		/* TODO: flush backend after dev ioctl. */
1910		if (r == -ENOIOCTLCMD)
1911			r = vhost_vring_ioctl(&vs->dev, ioctl, argp);
1912		mutex_unlock(&vs->dev.mutex);
1913		return r;
1914	}
1915}
1916
1917static const struct file_operations vhost_scsi_fops = {
1918	.owner          = THIS_MODULE,
1919	.release        = vhost_scsi_release,
1920	.unlocked_ioctl = vhost_scsi_ioctl,
1921	.compat_ioctl	= compat_ptr_ioctl,
1922	.open           = vhost_scsi_open,
1923	.llseek		= noop_llseek,
1924};
1925
1926static struct miscdevice vhost_scsi_misc = {
1927	MISC_DYNAMIC_MINOR,
1928	"vhost-scsi",
1929	&vhost_scsi_fops,
1930};
1931
1932static int __init vhost_scsi_register(void)
1933{
1934	return misc_register(&vhost_scsi_misc);
1935}
1936
1937static void vhost_scsi_deregister(void)
1938{
1939	misc_deregister(&vhost_scsi_misc);
1940}
1941
1942static char *vhost_scsi_dump_proto_id(struct vhost_scsi_tport *tport)
1943{
1944	switch (tport->tport_proto_id) {
1945	case SCSI_PROTOCOL_SAS:
1946		return "SAS";
1947	case SCSI_PROTOCOL_FCP:
1948		return "FCP";
1949	case SCSI_PROTOCOL_ISCSI:
1950		return "iSCSI";
1951	default:
1952		break;
1953	}
1954
1955	return "Unknown";
1956}
1957
1958static void
1959vhost_scsi_do_plug(struct vhost_scsi_tpg *tpg,
1960		  struct se_lun *lun, bool plug)
1961{
1962
1963	struct vhost_scsi *vs = tpg->vhost_scsi;
1964	struct vhost_virtqueue *vq;
1965	u32 reason;
1966
1967	if (!vs)
1968		return;
1969
1970	mutex_lock(&vs->dev.mutex);
1971
1972	if (plug)
1973		reason = VIRTIO_SCSI_EVT_RESET_RESCAN;
1974	else
1975		reason = VIRTIO_SCSI_EVT_RESET_REMOVED;
1976
1977	vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1978	mutex_lock(&vq->mutex);
1979	if (vhost_has_feature(vq, VIRTIO_SCSI_F_HOTPLUG))
1980		vhost_scsi_send_evt(vs, tpg, lun,
1981				   VIRTIO_SCSI_T_TRANSPORT_RESET, reason);
1982	mutex_unlock(&vq->mutex);
1983	mutex_unlock(&vs->dev.mutex);
1984}
1985
1986static void vhost_scsi_hotplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
1987{
1988	vhost_scsi_do_plug(tpg, lun, true);
1989}
1990
1991static void vhost_scsi_hotunplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
1992{
1993	vhost_scsi_do_plug(tpg, lun, false);
1994}
1995
1996static int vhost_scsi_port_link(struct se_portal_group *se_tpg,
1997			       struct se_lun *lun)
1998{
1999	struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2000				struct vhost_scsi_tpg, se_tpg);
2001	struct vhost_scsi_tmf *tmf;
2002
2003	tmf = kzalloc(sizeof(*tmf), GFP_KERNEL);
2004	if (!tmf)
2005		return -ENOMEM;
2006	INIT_LIST_HEAD(&tmf->queue_entry);
2007	vhost_work_init(&tmf->vwork, vhost_scsi_tmf_resp_work);
2008
2009	mutex_lock(&vhost_scsi_mutex);
2010
2011	mutex_lock(&tpg->tv_tpg_mutex);
2012	tpg->tv_tpg_port_count++;
2013	list_add_tail(&tmf->queue_entry, &tpg->tmf_queue);
2014	mutex_unlock(&tpg->tv_tpg_mutex);
2015
2016	vhost_scsi_hotplug(tpg, lun);
2017
2018	mutex_unlock(&vhost_scsi_mutex);
2019
2020	return 0;
2021}
2022
2023static void vhost_scsi_port_unlink(struct se_portal_group *se_tpg,
2024				  struct se_lun *lun)
2025{
2026	struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2027				struct vhost_scsi_tpg, se_tpg);
2028	struct vhost_scsi_tmf *tmf;
2029
2030	mutex_lock(&vhost_scsi_mutex);
2031
2032	mutex_lock(&tpg->tv_tpg_mutex);
2033	tpg->tv_tpg_port_count--;
2034	tmf = list_first_entry(&tpg->tmf_queue, struct vhost_scsi_tmf,
2035			       queue_entry);
2036	list_del(&tmf->queue_entry);
2037	kfree(tmf);
2038	mutex_unlock(&tpg->tv_tpg_mutex);
2039
2040	vhost_scsi_hotunplug(tpg, lun);
2041
2042	mutex_unlock(&vhost_scsi_mutex);
2043}
2044
2045static ssize_t vhost_scsi_tpg_attrib_fabric_prot_type_store(
2046		struct config_item *item, const char *page, size_t count)
2047{
2048	struct se_portal_group *se_tpg = attrib_to_tpg(item);
2049	struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2050				struct vhost_scsi_tpg, se_tpg);
2051	unsigned long val;
2052	int ret = kstrtoul(page, 0, &val);
2053
2054	if (ret) {
2055		pr_err("kstrtoul() returned %d for fabric_prot_type\n", ret);
2056		return ret;
2057	}
2058	if (val != 0 && val != 1 && val != 3) {
2059		pr_err("Invalid vhost_scsi fabric_prot_type: %lu\n", val);
2060		return -EINVAL;
2061	}
2062	tpg->tv_fabric_prot_type = val;
2063
2064	return count;
2065}
2066
2067static ssize_t vhost_scsi_tpg_attrib_fabric_prot_type_show(
2068		struct config_item *item, char *page)
2069{
2070	struct se_portal_group *se_tpg = attrib_to_tpg(item);
2071	struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2072				struct vhost_scsi_tpg, se_tpg);
2073
2074	return sprintf(page, "%d\n", tpg->tv_fabric_prot_type);
2075}
2076
2077CONFIGFS_ATTR(vhost_scsi_tpg_attrib_, fabric_prot_type);
2078
2079static struct configfs_attribute *vhost_scsi_tpg_attrib_attrs[] = {
2080	&vhost_scsi_tpg_attrib_attr_fabric_prot_type,
2081	NULL,
2082};
2083
2084static int vhost_scsi_make_nexus(struct vhost_scsi_tpg *tpg,
2085				const char *name)
2086{
2087	struct vhost_scsi_nexus *tv_nexus;
2088
2089	mutex_lock(&tpg->tv_tpg_mutex);
2090	if (tpg->tpg_nexus) {
2091		mutex_unlock(&tpg->tv_tpg_mutex);
2092		pr_debug("tpg->tpg_nexus already exists\n");
2093		return -EEXIST;
2094	}
2095
2096	tv_nexus = kzalloc(sizeof(*tv_nexus), GFP_KERNEL);
2097	if (!tv_nexus) {
2098		mutex_unlock(&tpg->tv_tpg_mutex);
2099		pr_err("Unable to allocate struct vhost_scsi_nexus\n");
2100		return -ENOMEM;
2101	}
2102	/*
2103	 * Since we are running in 'demo mode' this call with generate a
2104	 * struct se_node_acl for the vhost_scsi struct se_portal_group with
2105	 * the SCSI Initiator port name of the passed configfs group 'name'.
2106	 */
2107	tv_nexus->tvn_se_sess = target_setup_session(&tpg->se_tpg, 0, 0,
2108					TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS,
2109					(unsigned char *)name, tv_nexus, NULL);
2110	if (IS_ERR(tv_nexus->tvn_se_sess)) {
2111		mutex_unlock(&tpg->tv_tpg_mutex);
2112		kfree(tv_nexus);
2113		return -ENOMEM;
2114	}
2115	tpg->tpg_nexus = tv_nexus;
2116
2117	mutex_unlock(&tpg->tv_tpg_mutex);
2118	return 0;
2119}
2120
2121static int vhost_scsi_drop_nexus(struct vhost_scsi_tpg *tpg)
2122{
2123	struct se_session *se_sess;
2124	struct vhost_scsi_nexus *tv_nexus;
2125
2126	mutex_lock(&tpg->tv_tpg_mutex);
2127	tv_nexus = tpg->tpg_nexus;
2128	if (!tv_nexus) {
2129		mutex_unlock(&tpg->tv_tpg_mutex);
2130		return -ENODEV;
2131	}
2132
2133	se_sess = tv_nexus->tvn_se_sess;
2134	if (!se_sess) {
2135		mutex_unlock(&tpg->tv_tpg_mutex);
2136		return -ENODEV;
2137	}
2138
2139	if (tpg->tv_tpg_port_count != 0) {
2140		mutex_unlock(&tpg->tv_tpg_mutex);
2141		pr_err("Unable to remove TCM_vhost I_T Nexus with"
2142			" active TPG port count: %d\n",
2143			tpg->tv_tpg_port_count);
2144		return -EBUSY;
2145	}
2146
2147	if (tpg->tv_tpg_vhost_count != 0) {
2148		mutex_unlock(&tpg->tv_tpg_mutex);
2149		pr_err("Unable to remove TCM_vhost I_T Nexus with"
2150			" active TPG vhost count: %d\n",
2151			tpg->tv_tpg_vhost_count);
2152		return -EBUSY;
2153	}
2154
2155	pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated"
2156		" %s Initiator Port: %s\n", vhost_scsi_dump_proto_id(tpg->tport),
2157		tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
2158
2159	/*
2160	 * Release the SCSI I_T Nexus to the emulated vhost Target Port
2161	 */
2162	target_remove_session(se_sess);
2163	tpg->tpg_nexus = NULL;
2164	mutex_unlock(&tpg->tv_tpg_mutex);
2165
2166	kfree(tv_nexus);
2167	return 0;
2168}
2169
2170static ssize_t vhost_scsi_tpg_nexus_show(struct config_item *item, char *page)
2171{
2172	struct se_portal_group *se_tpg = to_tpg(item);
2173	struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2174				struct vhost_scsi_tpg, se_tpg);
2175	struct vhost_scsi_nexus *tv_nexus;
2176	ssize_t ret;
2177
2178	mutex_lock(&tpg->tv_tpg_mutex);
2179	tv_nexus = tpg->tpg_nexus;
2180	if (!tv_nexus) {
2181		mutex_unlock(&tpg->tv_tpg_mutex);
2182		return -ENODEV;
2183	}
2184	ret = snprintf(page, PAGE_SIZE, "%s\n",
2185			tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
2186	mutex_unlock(&tpg->tv_tpg_mutex);
2187
2188	return ret;
2189}
2190
2191static ssize_t vhost_scsi_tpg_nexus_store(struct config_item *item,
2192		const char *page, size_t count)
2193{
2194	struct se_portal_group *se_tpg = to_tpg(item);
2195	struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2196				struct vhost_scsi_tpg, se_tpg);
2197	struct vhost_scsi_tport *tport_wwn = tpg->tport;
2198	unsigned char i_port[VHOST_SCSI_NAMELEN], *ptr, *port_ptr;
2199	int ret;
2200	/*
2201	 * Shutdown the active I_T nexus if 'NULL' is passed..
2202	 */
2203	if (!strncmp(page, "NULL", 4)) {
2204		ret = vhost_scsi_drop_nexus(tpg);
2205		return (!ret) ? count : ret;
2206	}
2207	/*
2208	 * Otherwise make sure the passed virtual Initiator port WWN matches
2209	 * the fabric protocol_id set in vhost_scsi_make_tport(), and call
2210	 * vhost_scsi_make_nexus().
2211	 */
2212	if (strlen(page) >= VHOST_SCSI_NAMELEN) {
2213		pr_err("Emulated NAA Sas Address: %s, exceeds"
2214				" max: %d\n", page, VHOST_SCSI_NAMELEN);
2215		return -EINVAL;
2216	}
2217	snprintf(&i_port[0], VHOST_SCSI_NAMELEN, "%s", page);
2218
2219	ptr = strstr(i_port, "naa.");
2220	if (ptr) {
2221		if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
2222			pr_err("Passed SAS Initiator Port %s does not"
2223				" match target port protoid: %s\n", i_port,
2224				vhost_scsi_dump_proto_id(tport_wwn));
2225			return -EINVAL;
2226		}
2227		port_ptr = &i_port[0];
2228		goto check_newline;
2229	}
2230	ptr = strstr(i_port, "fc.");
2231	if (ptr) {
2232		if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
2233			pr_err("Passed FCP Initiator Port %s does not"
2234				" match target port protoid: %s\n", i_port,
2235				vhost_scsi_dump_proto_id(tport_wwn));
2236			return -EINVAL;
2237		}
2238		port_ptr = &i_port[3]; /* Skip over "fc." */
2239		goto check_newline;
2240	}
2241	ptr = strstr(i_port, "iqn.");
2242	if (ptr) {
2243		if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
2244			pr_err("Passed iSCSI Initiator Port %s does not"
2245				" match target port protoid: %s\n", i_port,
2246				vhost_scsi_dump_proto_id(tport_wwn));
2247			return -EINVAL;
2248		}
2249		port_ptr = &i_port[0];
2250		goto check_newline;
2251	}
2252	pr_err("Unable to locate prefix for emulated Initiator Port:"
2253			" %s\n", i_port);
2254	return -EINVAL;
2255	/*
2256	 * Clear any trailing newline for the NAA WWN
2257	 */
2258check_newline:
2259	if (i_port[strlen(i_port)-1] == '\n')
2260		i_port[strlen(i_port)-1] = '\0';
2261
2262	ret = vhost_scsi_make_nexus(tpg, port_ptr);
2263	if (ret < 0)
2264		return ret;
2265
2266	return count;
2267}
2268
2269CONFIGFS_ATTR(vhost_scsi_tpg_, nexus);
2270
2271static struct configfs_attribute *vhost_scsi_tpg_attrs[] = {
2272	&vhost_scsi_tpg_attr_nexus,
2273	NULL,
2274};
2275
2276static struct se_portal_group *
2277vhost_scsi_make_tpg(struct se_wwn *wwn, const char *name)
2278{
2279	struct vhost_scsi_tport *tport = container_of(wwn,
2280			struct vhost_scsi_tport, tport_wwn);
2281
2282	struct vhost_scsi_tpg *tpg;
2283	u16 tpgt;
2284	int ret;
2285
2286	if (strstr(name, "tpgt_") != name)
2287		return ERR_PTR(-EINVAL);
2288	if (kstrtou16(name + 5, 10, &tpgt) || tpgt >= VHOST_SCSI_MAX_TARGET)
2289		return ERR_PTR(-EINVAL);
2290
2291	tpg = kzalloc(sizeof(*tpg), GFP_KERNEL);
2292	if (!tpg) {
2293		pr_err("Unable to allocate struct vhost_scsi_tpg");
2294		return ERR_PTR(-ENOMEM);
2295	}
2296	mutex_init(&tpg->tv_tpg_mutex);
2297	INIT_LIST_HEAD(&tpg->tv_tpg_list);
2298	INIT_LIST_HEAD(&tpg->tmf_queue);
2299	tpg->tport = tport;
2300	tpg->tport_tpgt = tpgt;
2301
2302	ret = core_tpg_register(wwn, &tpg->se_tpg, tport->tport_proto_id);
2303	if (ret < 0) {
2304		kfree(tpg);
2305		return NULL;
2306	}
2307	mutex_lock(&vhost_scsi_mutex);
2308	list_add_tail(&tpg->tv_tpg_list, &vhost_scsi_list);
2309	mutex_unlock(&vhost_scsi_mutex);
2310
2311	return &tpg->se_tpg;
2312}
2313
2314static void vhost_scsi_drop_tpg(struct se_portal_group *se_tpg)
2315{
2316	struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2317				struct vhost_scsi_tpg, se_tpg);
2318
2319	mutex_lock(&vhost_scsi_mutex);
2320	list_del(&tpg->tv_tpg_list);
2321	mutex_unlock(&vhost_scsi_mutex);
2322	/*
2323	 * Release the virtual I_T Nexus for this vhost TPG
2324	 */
2325	vhost_scsi_drop_nexus(tpg);
2326	/*
2327	 * Deregister the se_tpg from TCM..
2328	 */
2329	core_tpg_deregister(se_tpg);
2330	kfree(tpg);
2331}
2332
2333static struct se_wwn *
2334vhost_scsi_make_tport(struct target_fabric_configfs *tf,
2335		     struct config_group *group,
2336		     const char *name)
2337{
2338	struct vhost_scsi_tport *tport;
2339	char *ptr;
2340	u64 wwpn = 0;
2341	int off = 0;
2342
2343	/* if (vhost_scsi_parse_wwn(name, &wwpn, 1) < 0)
2344		return ERR_PTR(-EINVAL); */
2345
2346	tport = kzalloc(sizeof(*tport), GFP_KERNEL);
2347	if (!tport) {
2348		pr_err("Unable to allocate struct vhost_scsi_tport");
2349		return ERR_PTR(-ENOMEM);
2350	}
2351	tport->tport_wwpn = wwpn;
2352	/*
2353	 * Determine the emulated Protocol Identifier and Target Port Name
2354	 * based on the incoming configfs directory name.
2355	 */
2356	ptr = strstr(name, "naa.");
2357	if (ptr) {
2358		tport->tport_proto_id = SCSI_PROTOCOL_SAS;
2359		goto check_len;
2360	}
2361	ptr = strstr(name, "fc.");
2362	if (ptr) {
2363		tport->tport_proto_id = SCSI_PROTOCOL_FCP;
2364		off = 3; /* Skip over "fc." */
2365		goto check_len;
2366	}
2367	ptr = strstr(name, "iqn.");
2368	if (ptr) {
2369		tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
2370		goto check_len;
2371	}
2372
2373	pr_err("Unable to locate prefix for emulated Target Port:"
2374			" %s\n", name);
2375	kfree(tport);
2376	return ERR_PTR(-EINVAL);
2377
2378check_len:
2379	if (strlen(name) >= VHOST_SCSI_NAMELEN) {
2380		pr_err("Emulated %s Address: %s, exceeds"
2381			" max: %d\n", name, vhost_scsi_dump_proto_id(tport),
2382			VHOST_SCSI_NAMELEN);
2383		kfree(tport);
2384		return ERR_PTR(-EINVAL);
2385	}
2386	snprintf(&tport->tport_name[0], VHOST_SCSI_NAMELEN, "%s", &name[off]);
2387
2388	pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target"
2389		" %s Address: %s\n", vhost_scsi_dump_proto_id(tport), name);
2390
2391	return &tport->tport_wwn;
2392}
2393
2394static void vhost_scsi_drop_tport(struct se_wwn *wwn)
2395{
2396	struct vhost_scsi_tport *tport = container_of(wwn,
2397				struct vhost_scsi_tport, tport_wwn);
2398
2399	pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target"
2400		" %s Address: %s\n", vhost_scsi_dump_proto_id(tport),
2401		tport->tport_name);
2402
2403	kfree(tport);
2404}
2405
2406static ssize_t
2407vhost_scsi_wwn_version_show(struct config_item *item, char *page)
2408{
2409	return sprintf(page, "TCM_VHOST fabric module %s on %s/%s"
2410		"on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
2411		utsname()->machine);
2412}
2413
2414CONFIGFS_ATTR_RO(vhost_scsi_wwn_, version);
2415
2416static struct configfs_attribute *vhost_scsi_wwn_attrs[] = {
2417	&vhost_scsi_wwn_attr_version,
2418	NULL,
2419};
2420
2421static const struct target_core_fabric_ops vhost_scsi_ops = {
2422	.module				= THIS_MODULE,
2423	.fabric_name			= "vhost",
2424	.max_data_sg_nents		= VHOST_SCSI_PREALLOC_SGLS,
2425	.tpg_get_wwn			= vhost_scsi_get_fabric_wwn,
2426	.tpg_get_tag			= vhost_scsi_get_tpgt,
2427	.tpg_check_demo_mode		= vhost_scsi_check_true,
2428	.tpg_check_demo_mode_cache	= vhost_scsi_check_true,
2429	.tpg_check_demo_mode_write_protect = vhost_scsi_check_false,
2430	.tpg_check_prod_mode_write_protect = vhost_scsi_check_false,
2431	.tpg_check_prot_fabric_only	= vhost_scsi_check_prot_fabric_only,
2432	.tpg_get_inst_index		= vhost_scsi_tpg_get_inst_index,
2433	.release_cmd			= vhost_scsi_release_cmd,
2434	.check_stop_free		= vhost_scsi_check_stop_free,
2435	.sess_get_index			= vhost_scsi_sess_get_index,
2436	.sess_get_initiator_sid		= NULL,
2437	.write_pending			= vhost_scsi_write_pending,
2438	.set_default_node_attributes	= vhost_scsi_set_default_node_attrs,
2439	.get_cmd_state			= vhost_scsi_get_cmd_state,
2440	.queue_data_in			= vhost_scsi_queue_data_in,
2441	.queue_status			= vhost_scsi_queue_status,
2442	.queue_tm_rsp			= vhost_scsi_queue_tm_rsp,
2443	.aborted_task			= vhost_scsi_aborted_task,
2444	/*
2445	 * Setup callers for generic logic in target_core_fabric_configfs.c
2446	 */
2447	.fabric_make_wwn		= vhost_scsi_make_tport,
2448	.fabric_drop_wwn		= vhost_scsi_drop_tport,
2449	.fabric_make_tpg		= vhost_scsi_make_tpg,
2450	.fabric_drop_tpg		= vhost_scsi_drop_tpg,
2451	.fabric_post_link		= vhost_scsi_port_link,
2452	.fabric_pre_unlink		= vhost_scsi_port_unlink,
2453
2454	.tfc_wwn_attrs			= vhost_scsi_wwn_attrs,
2455	.tfc_tpg_base_attrs		= vhost_scsi_tpg_attrs,
2456	.tfc_tpg_attrib_attrs		= vhost_scsi_tpg_attrib_attrs,
2457};
2458
2459static int __init vhost_scsi_init(void)
2460{
2461	int ret = -ENOMEM;
2462
2463	pr_debug("TCM_VHOST fabric module %s on %s/%s"
2464		" on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
2465		utsname()->machine);
2466
2467	ret = vhost_scsi_register();
2468	if (ret < 0)
2469		goto out;
2470
2471	ret = target_register_template(&vhost_scsi_ops);
2472	if (ret < 0)
2473		goto out_vhost_scsi_deregister;
2474
2475	return 0;
2476
2477out_vhost_scsi_deregister:
2478	vhost_scsi_deregister();
2479out:
2480	return ret;
2481};
2482
2483static void vhost_scsi_exit(void)
2484{
2485	target_unregister_template(&vhost_scsi_ops);
2486	vhost_scsi_deregister();
2487};
2488
2489MODULE_DESCRIPTION("VHOST_SCSI series fabric driver");
2490MODULE_ALIAS("tcm_vhost");
2491MODULE_LICENSE("GPL");
2492module_init(vhost_scsi_init);
2493module_exit(vhost_scsi_exit);