linux/drivers/vhost/scsi.c
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   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_free_evt(struct vhost_scsi *vs, struct tcm_vhost_evt *evt)
 543{
 544        vs->vs_events_nr--;
 545        kfree(evt);
 546}
 547
 548static struct tcm_vhost_evt *
 549tcm_vhost_allocate_evt(struct vhost_scsi *vs,
 550                       u32 event, u32 reason)
 551{
 552        struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 553        struct tcm_vhost_evt *evt;
 554
 555        if (vs->vs_events_nr > VHOST_SCSI_MAX_EVENT) {
 556                vs->vs_events_missed = true;
 557                return NULL;
 558        }
 559
 560        evt = kzalloc(sizeof(*evt), GFP_KERNEL);
 561        if (!evt) {
 562                vq_err(vq, "Failed to allocate tcm_vhost_evt\n");
 563                vs->vs_events_missed = true;
 564                return NULL;
 565        }
 566
 567        evt->event.event = event;
 568        evt->event.reason = reason;
 569        vs->vs_events_nr++;
 570
 571        return evt;
 572}
 573
 574static void vhost_scsi_free_cmd(struct tcm_vhost_cmd *cmd)
 575{
 576        struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
 577
 578        /* TODO locking against target/backend threads? */
 579        transport_generic_free_cmd(se_cmd, 0);
 580
 581}
 582
 583static int vhost_scsi_check_stop_free(struct se_cmd *se_cmd)
 584{
 585        return target_put_sess_cmd(se_cmd->se_sess, se_cmd);
 586}
 587
 588static void
 589tcm_vhost_do_evt_work(struct vhost_scsi *vs, struct tcm_vhost_evt *evt)
 590{
 591        struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 592        struct virtio_scsi_event *event = &evt->event;
 593        struct virtio_scsi_event __user *eventp;
 594        unsigned out, in;
 595        int head, ret;
 596
 597        if (!vq->private_data) {
 598                vs->vs_events_missed = true;
 599                return;
 600        }
 601
 602again:
 603        vhost_disable_notify(&vs->dev, vq);
 604        head = vhost_get_vq_desc(&vs->dev, vq, vq->iov,
 605                        ARRAY_SIZE(vq->iov), &out, &in,
 606                        NULL, NULL);
 607        if (head < 0) {
 608                vs->vs_events_missed = true;
 609                return;
 610        }
 611        if (head == vq->num) {
 612                if (vhost_enable_notify(&vs->dev, vq))
 613                        goto again;
 614                vs->vs_events_missed = true;
 615                return;
 616        }
 617
 618        if ((vq->iov[out].iov_len != sizeof(struct virtio_scsi_event))) {
 619                vq_err(vq, "Expecting virtio_scsi_event, got %zu bytes\n",
 620                                vq->iov[out].iov_len);
 621                vs->vs_events_missed = true;
 622                return;
 623        }
 624
 625        if (vs->vs_events_missed) {
 626                event->event |= VIRTIO_SCSI_T_EVENTS_MISSED;
 627                vs->vs_events_missed = false;
 628        }
 629
 630        eventp = vq->iov[out].iov_base;
 631        ret = __copy_to_user(eventp, event, sizeof(*event));
 632        if (!ret)
 633                vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 634        else
 635                vq_err(vq, "Faulted on tcm_vhost_send_event\n");
 636}
 637
 638static void tcm_vhost_evt_work(struct vhost_work *work)
 639{
 640        struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 641                                        vs_event_work);
 642        struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 643        struct tcm_vhost_evt *evt;
 644        struct llist_node *llnode;
 645
 646        mutex_lock(&vq->mutex);
 647        llnode = llist_del_all(&vs->vs_event_list);
 648        while (llnode) {
 649                evt = llist_entry(llnode, struct tcm_vhost_evt, list);
 650                llnode = llist_next(llnode);
 651                tcm_vhost_do_evt_work(vs, evt);
 652                tcm_vhost_free_evt(vs, evt);
 653        }
 654        mutex_unlock(&vq->mutex);
 655}
 656
 657/* Fill in status and signal that we are done processing this command
 658 *
 659 * This is scheduled in the vhost work queue so we are called with the owner
 660 * process mm and can access the vring.
 661 */
 662static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
 663{
 664        struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 665                                        vs_completion_work);
 666        DECLARE_BITMAP(signal, VHOST_SCSI_MAX_VQ);
 667        struct virtio_scsi_cmd_resp v_rsp;
 668        struct tcm_vhost_cmd *cmd;
 669        struct llist_node *llnode;
 670        struct se_cmd *se_cmd;
 671        int ret, vq;
 672
 673        bitmap_zero(signal, VHOST_SCSI_MAX_VQ);
 674        llnode = llist_del_all(&vs->vs_completion_list);
 675        while (llnode) {
 676                cmd = llist_entry(llnode, struct tcm_vhost_cmd,
 677                                     tvc_completion_list);
 678                llnode = llist_next(llnode);
 679                se_cmd = &cmd->tvc_se_cmd;
 680
 681                pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__,
 682                        cmd, se_cmd->residual_count, se_cmd->scsi_status);
 683
 684                memset(&v_rsp, 0, sizeof(v_rsp));
 685                v_rsp.resid = se_cmd->residual_count;
 686                /* TODO is status_qualifier field needed? */
 687                v_rsp.status = se_cmd->scsi_status;
 688                v_rsp.sense_len = se_cmd->scsi_sense_length;
 689                memcpy(v_rsp.sense, cmd->tvc_sense_buf,
 690                       v_rsp.sense_len);
 691                ret = copy_to_user(cmd->tvc_resp, &v_rsp, sizeof(v_rsp));
 692                if (likely(ret == 0)) {
 693                        struct vhost_scsi_virtqueue *q;
 694                        vhost_add_used(cmd->tvc_vq, cmd->tvc_vq_desc, 0);
 695                        q = container_of(cmd->tvc_vq, struct vhost_scsi_virtqueue, vq);
 696                        vq = q - vs->vqs;
 697                        __set_bit(vq, signal);
 698                } else
 699                        pr_err("Faulted on virtio_scsi_cmd_resp\n");
 700
 701                vhost_scsi_free_cmd(cmd);
 702        }
 703
 704        vq = -1;
 705        while ((vq = find_next_bit(signal, VHOST_SCSI_MAX_VQ, vq + 1))
 706                < VHOST_SCSI_MAX_VQ)
 707                vhost_signal(&vs->dev, &vs->vqs[vq].vq);
 708}
 709
 710static struct tcm_vhost_cmd *
 711vhost_scsi_get_tag(struct vhost_virtqueue *vq,
 712                        struct tcm_vhost_tpg *tpg,
 713                        struct virtio_scsi_cmd_req *v_req,
 714                        u32 exp_data_len,
 715                        int data_direction)
 716{
 717        struct tcm_vhost_cmd *cmd;
 718        struct tcm_vhost_nexus *tv_nexus;
 719        struct se_session *se_sess;
 720        struct scatterlist *sg;
 721        struct page **pages;
 722        int tag;
 723
 724        tv_nexus = tpg->tpg_nexus;
 725        if (!tv_nexus) {
 726                pr_err("Unable to locate active struct tcm_vhost_nexus\n");
 727                return ERR_PTR(-EIO);
 728        }
 729        se_sess = tv_nexus->tvn_se_sess;
 730
 731        tag = percpu_ida_alloc(&se_sess->sess_tag_pool, GFP_ATOMIC);
 732        if (tag < 0) {
 733                pr_err("Unable to obtain tag for tcm_vhost_cmd\n");
 734                return ERR_PTR(-ENOMEM);
 735        }
 736
 737        cmd = &((struct tcm_vhost_cmd *)se_sess->sess_cmd_map)[tag];
 738        sg = cmd->tvc_sgl;
 739        pages = cmd->tvc_upages;
 740        memset(cmd, 0, sizeof(struct tcm_vhost_cmd));
 741
 742        cmd->tvc_sgl = sg;
 743        cmd->tvc_upages = pages;
 744        cmd->tvc_se_cmd.map_tag = tag;
 745        cmd->tvc_tag = v_req->tag;
 746        cmd->tvc_task_attr = v_req->task_attr;
 747        cmd->tvc_exp_data_len = exp_data_len;
 748        cmd->tvc_data_direction = data_direction;
 749        cmd->tvc_nexus = tv_nexus;
 750        cmd->inflight = tcm_vhost_get_inflight(vq);
 751
 752        return cmd;
 753}
 754
 755/*
 756 * Map a user memory range into a scatterlist
 757 *
 758 * Returns the number of scatterlist entries used or -errno on error.
 759 */
 760static int
 761vhost_scsi_map_to_sgl(struct tcm_vhost_cmd *tv_cmd,
 762                      struct scatterlist *sgl,
 763                      unsigned int sgl_count,
 764                      struct iovec *iov,
 765                      int write)
 766{
 767        unsigned int npages = 0, pages_nr, offset, nbytes;
 768        struct scatterlist *sg = sgl;
 769        void __user *ptr = iov->iov_base;
 770        size_t len = iov->iov_len;
 771        struct page **pages;
 772        int ret, i;
 773
 774        if (sgl_count > TCM_VHOST_PREALLOC_SGLS) {
 775                pr_err("vhost_scsi_map_to_sgl() psgl_count: %u greater than"
 776                       " preallocated TCM_VHOST_PREALLOC_SGLS: %u\n",
 777                        sgl_count, TCM_VHOST_PREALLOC_SGLS);
 778                return -ENOBUFS;
 779        }
 780
 781        pages_nr = iov_num_pages(iov);
 782        if (pages_nr > sgl_count)
 783                return -ENOBUFS;
 784
 785        if (pages_nr > TCM_VHOST_PREALLOC_PAGES) {
 786                pr_err("vhost_scsi_map_to_sgl() pages_nr: %u greater than"
 787                       " preallocated TCM_VHOST_PREALLOC_PAGES: %u\n",
 788                        pages_nr, TCM_VHOST_PREALLOC_PAGES);
 789                return -ENOBUFS;
 790        }
 791
 792        pages = tv_cmd->tvc_upages;
 793
 794        ret = get_user_pages_fast((unsigned long)ptr, pages_nr, write, pages);
 795        /* No pages were pinned */
 796        if (ret < 0)
 797                goto out;
 798        /* Less pages pinned than wanted */
 799        if (ret != pages_nr) {
 800                for (i = 0; i < ret; i++)
 801                        put_page(pages[i]);
 802                ret = -EFAULT;
 803                goto out;
 804        }
 805
 806        while (len > 0) {
 807                offset = (uintptr_t)ptr & ~PAGE_MASK;
 808                nbytes = min_t(unsigned int, PAGE_SIZE - offset, len);
 809                sg_set_page(sg, pages[npages], nbytes, offset);
 810                ptr += nbytes;
 811                len -= nbytes;
 812                sg++;
 813                npages++;
 814        }
 815
 816out:
 817        return ret;
 818}
 819
 820static int
 821vhost_scsi_map_iov_to_sgl(struct tcm_vhost_cmd *cmd,
 822                          struct iovec *iov,
 823                          unsigned int niov,
 824                          int write)
 825{
 826        int ret;
 827        unsigned int i;
 828        u32 sgl_count;
 829        struct scatterlist *sg;
 830
 831        /*
 832         * Find out how long sglist needs to be
 833         */
 834        sgl_count = 0;
 835        for (i = 0; i < niov; i++)
 836                sgl_count += iov_num_pages(&iov[i]);
 837
 838        /* TODO overflow checking */
 839
 840        sg = cmd->tvc_sgl;
 841        pr_debug("%s sg %p sgl_count %u\n", __func__, sg, sgl_count);
 842        sg_init_table(sg, sgl_count);
 843
 844        cmd->tvc_sgl_count = sgl_count;
 845
 846        pr_debug("Mapping %u iovecs for %u pages\n", niov, sgl_count);
 847        for (i = 0; i < niov; i++) {
 848                ret = vhost_scsi_map_to_sgl(cmd, sg, sgl_count, &iov[i],
 849                                            write);
 850                if (ret < 0) {
 851                        for (i = 0; i < cmd->tvc_sgl_count; i++)
 852                                put_page(sg_page(&cmd->tvc_sgl[i]));
 853
 854                        cmd->tvc_sgl_count = 0;
 855                        return ret;
 856                }
 857
 858                sg += ret;
 859                sgl_count -= ret;
 860        }
 861        return 0;
 862}
 863
 864static void tcm_vhost_submission_work(struct work_struct *work)
 865{
 866        struct tcm_vhost_cmd *cmd =
 867                container_of(work, struct tcm_vhost_cmd, work);
 868        struct tcm_vhost_nexus *tv_nexus;
 869        struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
 870        struct scatterlist *sg_ptr, *sg_bidi_ptr = NULL;
 871        int rc, sg_no_bidi = 0;
 872
 873        if (cmd->tvc_sgl_count) {
 874                sg_ptr = cmd->tvc_sgl;
 875/* FIXME: Fix BIDI operation in tcm_vhost_submission_work() */
 876#if 0
 877                if (se_cmd->se_cmd_flags & SCF_BIDI) {
 878                        sg_bidi_ptr = NULL;
 879                        sg_no_bidi = 0;
 880                }
 881#endif
 882        } else {
 883                sg_ptr = NULL;
 884        }
 885        tv_nexus = cmd->tvc_nexus;
 886
 887        rc = target_submit_cmd_map_sgls(se_cmd, tv_nexus->tvn_se_sess,
 888                        cmd->tvc_cdb, &cmd->tvc_sense_buf[0],
 889                        cmd->tvc_lun, cmd->tvc_exp_data_len,
 890                        cmd->tvc_task_attr, cmd->tvc_data_direction,
 891                        TARGET_SCF_ACK_KREF, sg_ptr, cmd->tvc_sgl_count,
 892                        sg_bidi_ptr, sg_no_bidi);
 893        if (rc < 0) {
 894                transport_send_check_condition_and_sense(se_cmd,
 895                                TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
 896                transport_generic_free_cmd(se_cmd, 0);
 897        }
 898}
 899
 900static void
 901vhost_scsi_send_bad_target(struct vhost_scsi *vs,
 902                           struct vhost_virtqueue *vq,
 903                           int head, unsigned out)
 904{
 905        struct virtio_scsi_cmd_resp __user *resp;
 906        struct virtio_scsi_cmd_resp rsp;
 907        int ret;
 908
 909        memset(&rsp, 0, sizeof(rsp));
 910        rsp.response = VIRTIO_SCSI_S_BAD_TARGET;
 911        resp = vq->iov[out].iov_base;
 912        ret = __copy_to_user(resp, &rsp, sizeof(rsp));
 913        if (!ret)
 914                vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 915        else
 916                pr_err("Faulted on virtio_scsi_cmd_resp\n");
 917}
 918
 919static void
 920vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
 921{
 922        struct tcm_vhost_tpg **vs_tpg;
 923        struct virtio_scsi_cmd_req v_req;
 924        struct tcm_vhost_tpg *tpg;
 925        struct tcm_vhost_cmd *cmd;
 926        u32 exp_data_len, data_first, data_num, data_direction;
 927        unsigned out, in, i;
 928        int head, ret;
 929        u8 target;
 930
 931        mutex_lock(&vq->mutex);
 932        /*
 933         * We can handle the vq only after the endpoint is setup by calling the
 934         * VHOST_SCSI_SET_ENDPOINT ioctl.
 935         */
 936        vs_tpg = vq->private_data;
 937        if (!vs_tpg)
 938                goto out;
 939
 940        vhost_disable_notify(&vs->dev, vq);
 941
 942        for (;;) {
 943                head = vhost_get_vq_desc(&vs->dev, vq, vq->iov,
 944                                        ARRAY_SIZE(vq->iov), &out, &in,
 945                                        NULL, NULL);
 946                pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n",
 947                                        head, out, in);
 948                /* On error, stop handling until the next kick. */
 949                if (unlikely(head < 0))
 950                        break;
 951                /* Nothing new?  Wait for eventfd to tell us they refilled. */
 952                if (head == vq->num) {
 953                        if (unlikely(vhost_enable_notify(&vs->dev, vq))) {
 954                                vhost_disable_notify(&vs->dev, vq);
 955                                continue;
 956                        }
 957                        break;
 958                }
 959
 960/* FIXME: BIDI operation */
 961                if (out == 1 && in == 1) {
 962                        data_direction = DMA_NONE;
 963                        data_first = 0;
 964                        data_num = 0;
 965                } else if (out == 1 && in > 1) {
 966                        data_direction = DMA_FROM_DEVICE;
 967                        data_first = out + 1;
 968                        data_num = in - 1;
 969                } else if (out > 1 && in == 1) {
 970                        data_direction = DMA_TO_DEVICE;
 971                        data_first = 1;
 972                        data_num = out - 1;
 973                } else {
 974                        vq_err(vq, "Invalid buffer layout out: %u in: %u\n",
 975                                        out, in);
 976                        break;
 977                }
 978
 979                /*
 980                 * Check for a sane resp buffer so we can report errors to
 981                 * the guest.
 982                 */
 983                if (unlikely(vq->iov[out].iov_len !=
 984                                        sizeof(struct virtio_scsi_cmd_resp))) {
 985                        vq_err(vq, "Expecting virtio_scsi_cmd_resp, got %zu"
 986                                " bytes\n", vq->iov[out].iov_len);
 987                        break;
 988                }
 989
 990                if (unlikely(vq->iov[0].iov_len != sizeof(v_req))) {
 991                        vq_err(vq, "Expecting virtio_scsi_cmd_req, got %zu"
 992                                " bytes\n", vq->iov[0].iov_len);
 993                        break;
 994                }
 995                pr_debug("Calling __copy_from_user: vq->iov[0].iov_base: %p,"
 996                        " len: %zu\n", vq->iov[0].iov_base, sizeof(v_req));
 997                ret = __copy_from_user(&v_req, vq->iov[0].iov_base,
 998                                sizeof(v_req));
 999                if (unlikely(ret)) {
1000                        vq_err(vq, "Faulted on virtio_scsi_cmd_req\n");
1001                        break;
1002                }
1003
1004                /* Extract the tpgt */
1005                target = v_req.lun[1];
1006                tpg = ACCESS_ONCE(vs_tpg[target]);
1007
1008                /* Target does not exist, fail the request */
1009                if (unlikely(!tpg)) {
1010                        vhost_scsi_send_bad_target(vs, vq, head, out);
1011                        continue;
1012                }
1013
1014                exp_data_len = 0;
1015                for (i = 0; i < data_num; i++)
1016                        exp_data_len += vq->iov[data_first + i].iov_len;
1017
1018                cmd = vhost_scsi_get_tag(vq, tpg, &v_req,
1019                                         exp_data_len, data_direction);
1020                if (IS_ERR(cmd)) {
1021                        vq_err(vq, "vhost_scsi_get_tag failed %ld\n",
1022                                        PTR_ERR(cmd));
1023                        goto err_cmd;
1024                }
1025                pr_debug("Allocated tv_cmd: %p exp_data_len: %d, data_direction"
1026                        ": %d\n", cmd, exp_data_len, data_direction);
1027
1028                cmd->tvc_vhost = vs;
1029                cmd->tvc_vq = vq;
1030                cmd->tvc_resp = vq->iov[out].iov_base;
1031
1032                /*
1033                 * Copy in the recieved CDB descriptor into cmd->tvc_cdb
1034                 * that will be used by tcm_vhost_new_cmd_map() and down into
1035                 * target_setup_cmd_from_cdb()
1036                 */
1037                memcpy(cmd->tvc_cdb, v_req.cdb, TCM_VHOST_MAX_CDB_SIZE);
1038                /*
1039                 * Check that the recieved CDB size does not exceeded our
1040                 * hardcoded max for tcm_vhost
1041                 */
1042                /* TODO what if cdb was too small for varlen cdb header? */
1043                if (unlikely(scsi_command_size(cmd->tvc_cdb) >
1044                                        TCM_VHOST_MAX_CDB_SIZE)) {
1045                        vq_err(vq, "Received SCSI CDB with command_size: %d that"
1046                                " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1047                                scsi_command_size(cmd->tvc_cdb),
1048                                TCM_VHOST_MAX_CDB_SIZE);
1049                        goto err_free;
1050                }
1051                cmd->tvc_lun = ((v_req.lun[2] << 8) | v_req.lun[3]) & 0x3FFF;
1052
1053                pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n",
1054                        cmd->tvc_cdb[0], cmd->tvc_lun);
1055
1056                if (data_direction != DMA_NONE) {
1057                        ret = vhost_scsi_map_iov_to_sgl(cmd,
1058                                        &vq->iov[data_first], data_num,
1059                                        data_direction == DMA_FROM_DEVICE);
1060                        if (unlikely(ret)) {
1061                                vq_err(vq, "Failed to map iov to sgl\n");
1062                                goto err_free;
1063                        }
1064                }
1065
1066                /*
1067                 * Save the descriptor from vhost_get_vq_desc() to be used to
1068                 * complete the virtio-scsi request in TCM callback context via
1069                 * tcm_vhost_queue_data_in() and tcm_vhost_queue_status()
1070                 */
1071                cmd->tvc_vq_desc = head;
1072                /*
1073                 * Dispatch tv_cmd descriptor for cmwq execution in process
1074                 * context provided by tcm_vhost_workqueue.  This also ensures
1075                 * tv_cmd is executed on the same kworker CPU as this vhost
1076                 * thread to gain positive L2 cache locality effects..
1077                 */
1078                INIT_WORK(&cmd->work, tcm_vhost_submission_work);
1079                queue_work(tcm_vhost_workqueue, &cmd->work);
1080        }
1081
1082        mutex_unlock(&vq->mutex);
1083        return;
1084
1085err_free:
1086        vhost_scsi_free_cmd(cmd);
1087err_cmd:
1088        vhost_scsi_send_bad_target(vs, vq, head, out);
1089out:
1090        mutex_unlock(&vq->mutex);
1091}
1092
1093static void vhost_scsi_ctl_handle_kick(struct vhost_work *work)
1094{
1095        pr_debug("%s: The handling func for control queue.\n", __func__);
1096}
1097
1098static void
1099tcm_vhost_send_evt(struct vhost_scsi *vs,
1100                   struct tcm_vhost_tpg *tpg,
1101                   struct se_lun *lun,
1102                   u32 event,
1103                   u32 reason)
1104{
1105        struct tcm_vhost_evt *evt;
1106
1107        evt = tcm_vhost_allocate_evt(vs, event, reason);
1108        if (!evt)
1109                return;
1110
1111        if (tpg && lun) {
1112                /* TODO: share lun setup code with virtio-scsi.ko */
1113                /*
1114                 * Note: evt->event is zeroed when we allocate it and
1115                 * lun[4-7] need to be zero according to virtio-scsi spec.
1116                 */
1117                evt->event.lun[0] = 0x01;
1118                evt->event.lun[1] = tpg->tport_tpgt & 0xFF;
1119                if (lun->unpacked_lun >= 256)
1120                        evt->event.lun[2] = lun->unpacked_lun >> 8 | 0x40 ;
1121                evt->event.lun[3] = lun->unpacked_lun & 0xFF;
1122        }
1123
1124        llist_add(&evt->list, &vs->vs_event_list);
1125        vhost_work_queue(&vs->dev, &vs->vs_event_work);
1126}
1127
1128static void vhost_scsi_evt_handle_kick(struct vhost_work *work)
1129{
1130        struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1131                                                poll.work);
1132        struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1133
1134        mutex_lock(&vq->mutex);
1135        if (!vq->private_data)
1136                goto out;
1137
1138        if (vs->vs_events_missed)
1139                tcm_vhost_send_evt(vs, NULL, NULL, VIRTIO_SCSI_T_NO_EVENT, 0);
1140out:
1141        mutex_unlock(&vq->mutex);
1142}
1143
1144static void vhost_scsi_handle_kick(struct vhost_work *work)
1145{
1146        struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1147                                                poll.work);
1148        struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1149
1150        vhost_scsi_handle_vq(vs, vq);
1151}
1152
1153static void vhost_scsi_flush_vq(struct vhost_scsi *vs, int index)
1154{
1155        vhost_poll_flush(&vs->vqs[index].vq.poll);
1156}
1157
1158/* Callers must hold dev mutex */
1159static void vhost_scsi_flush(struct vhost_scsi *vs)
1160{
1161        struct vhost_scsi_inflight *old_inflight[VHOST_SCSI_MAX_VQ];
1162        int i;
1163
1164        /* Init new inflight and remember the old inflight */
1165        tcm_vhost_init_inflight(vs, old_inflight);
1166
1167        /*
1168         * The inflight->kref was initialized to 1. We decrement it here to
1169         * indicate the start of the flush operation so that it will reach 0
1170         * when all the reqs are finished.
1171         */
1172        for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1173                kref_put(&old_inflight[i]->kref, tcm_vhost_done_inflight);
1174
1175        /* Flush both the vhost poll and vhost work */
1176        for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1177                vhost_scsi_flush_vq(vs, i);
1178        vhost_work_flush(&vs->dev, &vs->vs_completion_work);
1179        vhost_work_flush(&vs->dev, &vs->vs_event_work);
1180
1181        /* Wait for all reqs issued before the flush to be finished */
1182        for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1183                wait_for_completion(&old_inflight[i]->comp);
1184}
1185
1186/*
1187 * Called from vhost_scsi_ioctl() context to walk the list of available
1188 * tcm_vhost_tpg with an active struct tcm_vhost_nexus
1189 *
1190 *  The lock nesting rule is:
1191 *    tcm_vhost_mutex -> vs->dev.mutex -> tpg->tv_tpg_mutex -> vq->mutex
1192 */
1193static int
1194vhost_scsi_set_endpoint(struct vhost_scsi *vs,
1195                        struct vhost_scsi_target *t)
1196{
1197        struct tcm_vhost_tport *tv_tport;
1198        struct tcm_vhost_tpg *tpg;
1199        struct tcm_vhost_tpg **vs_tpg;
1200        struct vhost_virtqueue *vq;
1201        int index, ret, i, len;
1202        bool match = false;
1203
1204        mutex_lock(&tcm_vhost_mutex);
1205        mutex_lock(&vs->dev.mutex);
1206
1207        /* Verify that ring has been setup correctly. */
1208        for (index = 0; index < vs->dev.nvqs; ++index) {
1209                /* Verify that ring has been setup correctly. */
1210                if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1211                        ret = -EFAULT;
1212                        goto out;
1213                }
1214        }
1215
1216        len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET;
1217        vs_tpg = kzalloc(len, GFP_KERNEL);
1218        if (!vs_tpg) {
1219                ret = -ENOMEM;
1220                goto out;
1221        }
1222        if (vs->vs_tpg)
1223                memcpy(vs_tpg, vs->vs_tpg, len);
1224
1225        list_for_each_entry(tpg, &tcm_vhost_list, tv_tpg_list) {
1226                mutex_lock(&tpg->tv_tpg_mutex);
1227                if (!tpg->tpg_nexus) {
1228                        mutex_unlock(&tpg->tv_tpg_mutex);
1229                        continue;
1230                }
1231                if (tpg->tv_tpg_vhost_count != 0) {
1232                        mutex_unlock(&tpg->tv_tpg_mutex);
1233                        continue;
1234                }
1235                tv_tport = tpg->tport;
1236
1237                if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1238                        if (vs->vs_tpg && vs->vs_tpg[tpg->tport_tpgt]) {
1239                                kfree(vs_tpg);
1240                                mutex_unlock(&tpg->tv_tpg_mutex);
1241                                ret = -EEXIST;
1242                                goto out;
1243                        }
1244                        tpg->tv_tpg_vhost_count++;
1245                        tpg->vhost_scsi = vs;
1246                        vs_tpg[tpg->tport_tpgt] = tpg;
1247                        smp_mb__after_atomic_inc();
1248                        match = true;
1249                }
1250                mutex_unlock(&tpg->tv_tpg_mutex);
1251        }
1252
1253        if (match) {
1254                memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
1255                       sizeof(vs->vs_vhost_wwpn));
1256                for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1257                        vq = &vs->vqs[i].vq;
1258                        mutex_lock(&vq->mutex);
1259                        vq->private_data = vs_tpg;
1260                        vhost_init_used(vq);
1261                        mutex_unlock(&vq->mutex);
1262                }
1263                ret = 0;
1264        } else {
1265                ret = -EEXIST;
1266        }
1267
1268        /*
1269         * Act as synchronize_rcu to make sure access to
1270         * old vs->vs_tpg is finished.
1271         */
1272        vhost_scsi_flush(vs);
1273        kfree(vs->vs_tpg);
1274        vs->vs_tpg = vs_tpg;
1275
1276out:
1277        mutex_unlock(&vs->dev.mutex);
1278        mutex_unlock(&tcm_vhost_mutex);
1279        return ret;
1280}
1281
1282static int
1283vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
1284                          struct vhost_scsi_target *t)
1285{
1286        struct tcm_vhost_tport *tv_tport;
1287        struct tcm_vhost_tpg *tpg;
1288        struct vhost_virtqueue *vq;
1289        bool match = false;
1290        int index, ret, i;
1291        u8 target;
1292
1293        mutex_lock(&tcm_vhost_mutex);
1294        mutex_lock(&vs->dev.mutex);
1295        /* Verify that ring has been setup correctly. */
1296        for (index = 0; index < vs->dev.nvqs; ++index) {
1297                if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1298                        ret = -EFAULT;
1299                        goto err_dev;
1300                }
1301        }
1302
1303        if (!vs->vs_tpg) {
1304                ret = 0;
1305                goto err_dev;
1306        }
1307
1308        for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1309                target = i;
1310                tpg = vs->vs_tpg[target];
1311                if (!tpg)
1312                        continue;
1313
1314                mutex_lock(&tpg->tv_tpg_mutex);
1315                tv_tport = tpg->tport;
1316                if (!tv_tport) {
1317                        ret = -ENODEV;
1318                        goto err_tpg;
1319                }
1320
1321                if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1322                        pr_warn("tv_tport->tport_name: %s, tpg->tport_tpgt: %hu"
1323                                " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
1324                                tv_tport->tport_name, tpg->tport_tpgt,
1325                                t->vhost_wwpn, t->vhost_tpgt);
1326                        ret = -EINVAL;
1327                        goto err_tpg;
1328                }
1329                tpg->tv_tpg_vhost_count--;
1330                tpg->vhost_scsi = NULL;
1331                vs->vs_tpg[target] = NULL;
1332                match = true;
1333                mutex_unlock(&tpg->tv_tpg_mutex);
1334        }
1335        if (match) {
1336                for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1337                        vq = &vs->vqs[i].vq;
1338                        mutex_lock(&vq->mutex);
1339                        vq->private_data = NULL;
1340                        mutex_unlock(&vq->mutex);
1341                }
1342        }
1343        /*
1344         * Act as synchronize_rcu to make sure access to
1345         * old vs->vs_tpg is finished.
1346         */
1347        vhost_scsi_flush(vs);
1348        kfree(vs->vs_tpg);
1349        vs->vs_tpg = NULL;
1350        WARN_ON(vs->vs_events_nr);
1351        mutex_unlock(&vs->dev.mutex);
1352        mutex_unlock(&tcm_vhost_mutex);
1353        return 0;
1354
1355err_tpg:
1356        mutex_unlock(&tpg->tv_tpg_mutex);
1357err_dev:
1358        mutex_unlock(&vs->dev.mutex);
1359        mutex_unlock(&tcm_vhost_mutex);
1360        return ret;
1361}
1362
1363static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features)
1364{
1365        if (features & ~VHOST_SCSI_FEATURES)
1366                return -EOPNOTSUPP;
1367
1368        mutex_lock(&vs->dev.mutex);
1369        if ((features & (1 << VHOST_F_LOG_ALL)) &&
1370            !vhost_log_access_ok(&vs->dev)) {
1371                mutex_unlock(&vs->dev.mutex);
1372                return -EFAULT;
1373        }
1374        vs->dev.acked_features = features;
1375        smp_wmb();
1376        vhost_scsi_flush(vs);
1377        mutex_unlock(&vs->dev.mutex);
1378        return 0;
1379}
1380
1381static void vhost_scsi_free(struct vhost_scsi *vs)
1382{
1383        if (is_vmalloc_addr(vs))
1384                vfree(vs);
1385        else
1386                kfree(vs);
1387}
1388
1389static int vhost_scsi_open(struct inode *inode, struct file *f)
1390{
1391        struct vhost_scsi *vs;
1392        struct vhost_virtqueue **vqs;
1393        int r = -ENOMEM, i;
1394
1395        vs = kzalloc(sizeof(*vs), GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
1396        if (!vs) {
1397                vs = vzalloc(sizeof(*vs));
1398                if (!vs)
1399                        goto err_vs;
1400        }
1401
1402        vqs = kmalloc(VHOST_SCSI_MAX_VQ * sizeof(*vqs), GFP_KERNEL);
1403        if (!vqs)
1404                goto err_vqs;
1405
1406        vhost_work_init(&vs->vs_completion_work, vhost_scsi_complete_cmd_work);
1407        vhost_work_init(&vs->vs_event_work, tcm_vhost_evt_work);
1408
1409        vs->vs_events_nr = 0;
1410        vs->vs_events_missed = false;
1411
1412        vqs[VHOST_SCSI_VQ_CTL] = &vs->vqs[VHOST_SCSI_VQ_CTL].vq;
1413        vqs[VHOST_SCSI_VQ_EVT] = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1414        vs->vqs[VHOST_SCSI_VQ_CTL].vq.handle_kick = vhost_scsi_ctl_handle_kick;
1415        vs->vqs[VHOST_SCSI_VQ_EVT].vq.handle_kick = vhost_scsi_evt_handle_kick;
1416        for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++) {
1417                vqs[i] = &vs->vqs[i].vq;
1418                vs->vqs[i].vq.handle_kick = vhost_scsi_handle_kick;
1419        }
1420        r = vhost_dev_init(&vs->dev, vqs, VHOST_SCSI_MAX_VQ);
1421
1422        tcm_vhost_init_inflight(vs, NULL);
1423
1424        if (r < 0)
1425                goto err_init;
1426
1427        f->private_data = vs;
1428        return 0;
1429
1430err_init:
1431        kfree(vqs);
1432err_vqs:
1433        vhost_scsi_free(vs);
1434err_vs:
1435        return r;
1436}
1437
1438static int vhost_scsi_release(struct inode *inode, struct file *f)
1439{
1440        struct vhost_scsi *vs = f->private_data;
1441        struct vhost_scsi_target t;
1442
1443        mutex_lock(&vs->dev.mutex);
1444        memcpy(t.vhost_wwpn, vs->vs_vhost_wwpn, sizeof(t.vhost_wwpn));
1445        mutex_unlock(&vs->dev.mutex);
1446        vhost_scsi_clear_endpoint(vs, &t);
1447        vhost_dev_stop(&vs->dev);
1448        vhost_dev_cleanup(&vs->dev, false);
1449        /* Jobs can re-queue themselves in evt kick handler. Do extra flush. */
1450        vhost_scsi_flush(vs);
1451        kfree(vs->dev.vqs);
1452        vhost_scsi_free(vs);
1453        return 0;
1454}
1455
1456static long
1457vhost_scsi_ioctl(struct file *f,
1458                 unsigned int ioctl,
1459                 unsigned long arg)
1460{
1461        struct vhost_scsi *vs = f->private_data;
1462        struct vhost_scsi_target backend;
1463        void __user *argp = (void __user *)arg;
1464        u64 __user *featurep = argp;
1465        u32 __user *eventsp = argp;
1466        u32 events_missed;
1467        u64 features;
1468        int r, abi_version = VHOST_SCSI_ABI_VERSION;
1469        struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1470
1471        switch (ioctl) {
1472        case VHOST_SCSI_SET_ENDPOINT:
1473                if (copy_from_user(&backend, argp, sizeof backend))
1474                        return -EFAULT;
1475                if (backend.reserved != 0)
1476                        return -EOPNOTSUPP;
1477
1478                return vhost_scsi_set_endpoint(vs, &backend);
1479        case VHOST_SCSI_CLEAR_ENDPOINT:
1480                if (copy_from_user(&backend, argp, sizeof backend))
1481                        return -EFAULT;
1482                if (backend.reserved != 0)
1483                        return -EOPNOTSUPP;
1484
1485                return vhost_scsi_clear_endpoint(vs, &backend);
1486        case VHOST_SCSI_GET_ABI_VERSION:
1487                if (copy_to_user(argp, &abi_version, sizeof abi_version))
1488                        return -EFAULT;
1489                return 0;
1490        case VHOST_SCSI_SET_EVENTS_MISSED:
1491                if (get_user(events_missed, eventsp))
1492                        return -EFAULT;
1493                mutex_lock(&vq->mutex);
1494                vs->vs_events_missed = events_missed;
1495                mutex_unlock(&vq->mutex);
1496                return 0;
1497        case VHOST_SCSI_GET_EVENTS_MISSED:
1498                mutex_lock(&vq->mutex);
1499                events_missed = vs->vs_events_missed;
1500                mutex_unlock(&vq->mutex);
1501                if (put_user(events_missed, eventsp))
1502                        return -EFAULT;
1503                return 0;
1504        case VHOST_GET_FEATURES:
1505                features = VHOST_SCSI_FEATURES;
1506                if (copy_to_user(featurep, &features, sizeof features))
1507                        return -EFAULT;
1508                return 0;
1509        case VHOST_SET_FEATURES:
1510                if (copy_from_user(&features, featurep, sizeof features))
1511                        return -EFAULT;
1512                return vhost_scsi_set_features(vs, features);
1513        default:
1514                mutex_lock(&vs->dev.mutex);
1515                r = vhost_dev_ioctl(&vs->dev, ioctl, argp);
1516                /* TODO: flush backend after dev ioctl. */
1517                if (r == -ENOIOCTLCMD)
1518                        r = vhost_vring_ioctl(&vs->dev, ioctl, argp);
1519                mutex_unlock(&vs->dev.mutex);
1520                return r;
1521        }
1522}
1523
1524#ifdef CONFIG_COMPAT
1525static long vhost_scsi_compat_ioctl(struct file *f, unsigned int ioctl,
1526                                unsigned long arg)
1527{
1528        return vhost_scsi_ioctl(f, ioctl, (unsigned long)compat_ptr(arg));
1529}
1530#endif
1531
1532static const struct file_operations vhost_scsi_fops = {
1533        .owner          = THIS_MODULE,
1534        .release        = vhost_scsi_release,
1535        .unlocked_ioctl = vhost_scsi_ioctl,
1536#ifdef CONFIG_COMPAT
1537        .compat_ioctl   = vhost_scsi_compat_ioctl,
1538#endif
1539        .open           = vhost_scsi_open,
1540        .llseek         = noop_llseek,
1541};
1542
1543static struct miscdevice vhost_scsi_misc = {
1544        MISC_DYNAMIC_MINOR,
1545        "vhost-scsi",
1546        &vhost_scsi_fops,
1547};
1548
1549static int __init vhost_scsi_register(void)
1550{
1551        return misc_register(&vhost_scsi_misc);
1552}
1553
1554static int vhost_scsi_deregister(void)
1555{
1556        return misc_deregister(&vhost_scsi_misc);
1557}
1558
1559static char *tcm_vhost_dump_proto_id(struct tcm_vhost_tport *tport)
1560{
1561        switch (tport->tport_proto_id) {
1562        case SCSI_PROTOCOL_SAS:
1563                return "SAS";
1564        case SCSI_PROTOCOL_FCP:
1565                return "FCP";
1566        case SCSI_PROTOCOL_ISCSI:
1567                return "iSCSI";
1568        default:
1569                break;
1570        }
1571
1572        return "Unknown";
1573}
1574
1575static void
1576tcm_vhost_do_plug(struct tcm_vhost_tpg *tpg,
1577                  struct se_lun *lun, bool plug)
1578{
1579
1580        struct vhost_scsi *vs = tpg->vhost_scsi;
1581        struct vhost_virtqueue *vq;
1582        u32 reason;
1583
1584        if (!vs)
1585                return;
1586
1587        mutex_lock(&vs->dev.mutex);
1588        if (!vhost_has_feature(&vs->dev, VIRTIO_SCSI_F_HOTPLUG)) {
1589                mutex_unlock(&vs->dev.mutex);
1590                return;
1591        }
1592
1593        if (plug)
1594                reason = VIRTIO_SCSI_EVT_RESET_RESCAN;
1595        else
1596                reason = VIRTIO_SCSI_EVT_RESET_REMOVED;
1597
1598        vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1599        mutex_lock(&vq->mutex);
1600        tcm_vhost_send_evt(vs, tpg, lun,
1601                        VIRTIO_SCSI_T_TRANSPORT_RESET, reason);
1602        mutex_unlock(&vq->mutex);
1603        mutex_unlock(&vs->dev.mutex);
1604}
1605
1606static void tcm_vhost_hotplug(struct tcm_vhost_tpg *tpg, struct se_lun *lun)
1607{
1608        tcm_vhost_do_plug(tpg, lun, true);
1609}
1610
1611static void tcm_vhost_hotunplug(struct tcm_vhost_tpg *tpg, struct se_lun *lun)
1612{
1613        tcm_vhost_do_plug(tpg, lun, false);
1614}
1615
1616static int tcm_vhost_port_link(struct se_portal_group *se_tpg,
1617                               struct se_lun *lun)
1618{
1619        struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1620                                struct tcm_vhost_tpg, se_tpg);
1621
1622        mutex_lock(&tcm_vhost_mutex);
1623
1624        mutex_lock(&tpg->tv_tpg_mutex);
1625        tpg->tv_tpg_port_count++;
1626        mutex_unlock(&tpg->tv_tpg_mutex);
1627
1628        tcm_vhost_hotplug(tpg, lun);
1629
1630        mutex_unlock(&tcm_vhost_mutex);
1631
1632        return 0;
1633}
1634
1635static void tcm_vhost_port_unlink(struct se_portal_group *se_tpg,
1636                                  struct se_lun *lun)
1637{
1638        struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1639                                struct tcm_vhost_tpg, se_tpg);
1640
1641        mutex_lock(&tcm_vhost_mutex);
1642
1643        mutex_lock(&tpg->tv_tpg_mutex);
1644        tpg->tv_tpg_port_count--;
1645        mutex_unlock(&tpg->tv_tpg_mutex);
1646
1647        tcm_vhost_hotunplug(tpg, lun);
1648
1649        mutex_unlock(&tcm_vhost_mutex);
1650}
1651
1652static struct se_node_acl *
1653tcm_vhost_make_nodeacl(struct se_portal_group *se_tpg,
1654                       struct config_group *group,
1655                       const char *name)
1656{
1657        struct se_node_acl *se_nacl, *se_nacl_new;
1658        struct tcm_vhost_nacl *nacl;
1659        u64 wwpn = 0;
1660        u32 nexus_depth;
1661
1662        /* tcm_vhost_parse_wwn(name, &wwpn, 1) < 0)
1663                return ERR_PTR(-EINVAL); */
1664        se_nacl_new = tcm_vhost_alloc_fabric_acl(se_tpg);
1665        if (!se_nacl_new)
1666                return ERR_PTR(-ENOMEM);
1667
1668        nexus_depth = 1;
1669        /*
1670         * se_nacl_new may be released by core_tpg_add_initiator_node_acl()
1671         * when converting a NodeACL from demo mode -> explict
1672         */
1673        se_nacl = core_tpg_add_initiator_node_acl(se_tpg, se_nacl_new,
1674                                name, nexus_depth);
1675        if (IS_ERR(se_nacl)) {
1676                tcm_vhost_release_fabric_acl(se_tpg, se_nacl_new);
1677                return se_nacl;
1678        }
1679        /*
1680         * Locate our struct tcm_vhost_nacl and set the FC Nport WWPN
1681         */
1682        nacl = container_of(se_nacl, struct tcm_vhost_nacl, se_node_acl);
1683        nacl->iport_wwpn = wwpn;
1684
1685        return se_nacl;
1686}
1687
1688static void tcm_vhost_drop_nodeacl(struct se_node_acl *se_acl)
1689{
1690        struct tcm_vhost_nacl *nacl = container_of(se_acl,
1691                                struct tcm_vhost_nacl, se_node_acl);
1692        core_tpg_del_initiator_node_acl(se_acl->se_tpg, se_acl, 1);
1693        kfree(nacl);
1694}
1695
1696static void tcm_vhost_free_cmd_map_res(struct tcm_vhost_nexus *nexus,
1697                                       struct se_session *se_sess)
1698{
1699        struct tcm_vhost_cmd *tv_cmd;
1700        unsigned int i;
1701
1702        if (!se_sess->sess_cmd_map)
1703                return;
1704
1705        for (i = 0; i < TCM_VHOST_DEFAULT_TAGS; i++) {
1706                tv_cmd = &((struct tcm_vhost_cmd *)se_sess->sess_cmd_map)[i];
1707
1708                kfree(tv_cmd->tvc_sgl);
1709                kfree(tv_cmd->tvc_upages);
1710        }
1711}
1712
1713static int tcm_vhost_make_nexus(struct tcm_vhost_tpg *tpg,
1714                                const char *name)
1715{
1716        struct se_portal_group *se_tpg;
1717        struct se_session *se_sess;
1718        struct tcm_vhost_nexus *tv_nexus;
1719        struct tcm_vhost_cmd *tv_cmd;
1720        unsigned int i;
1721
1722        mutex_lock(&tpg->tv_tpg_mutex);
1723        if (tpg->tpg_nexus) {
1724                mutex_unlock(&tpg->tv_tpg_mutex);
1725                pr_debug("tpg->tpg_nexus already exists\n");
1726                return -EEXIST;
1727        }
1728        se_tpg = &tpg->se_tpg;
1729
1730        tv_nexus = kzalloc(sizeof(struct tcm_vhost_nexus), GFP_KERNEL);
1731        if (!tv_nexus) {
1732                mutex_unlock(&tpg->tv_tpg_mutex);
1733                pr_err("Unable to allocate struct tcm_vhost_nexus\n");
1734                return -ENOMEM;
1735        }
1736        /*
1737         *  Initialize the struct se_session pointer and setup tagpool
1738         *  for struct tcm_vhost_cmd descriptors
1739         */
1740        tv_nexus->tvn_se_sess = transport_init_session_tags(
1741                                        TCM_VHOST_DEFAULT_TAGS,
1742                                        sizeof(struct tcm_vhost_cmd));
1743        if (IS_ERR(tv_nexus->tvn_se_sess)) {
1744                mutex_unlock(&tpg->tv_tpg_mutex);
1745                kfree(tv_nexus);
1746                return -ENOMEM;
1747        }
1748        se_sess = tv_nexus->tvn_se_sess;
1749        for (i = 0; i < TCM_VHOST_DEFAULT_TAGS; i++) {
1750                tv_cmd = &((struct tcm_vhost_cmd *)se_sess->sess_cmd_map)[i];
1751
1752                tv_cmd->tvc_sgl = kzalloc(sizeof(struct scatterlist) *
1753                                        TCM_VHOST_PREALLOC_SGLS, GFP_KERNEL);
1754                if (!tv_cmd->tvc_sgl) {
1755                        mutex_unlock(&tpg->tv_tpg_mutex);
1756                        pr_err("Unable to allocate tv_cmd->tvc_sgl\n");
1757                        goto out;
1758                }
1759
1760                tv_cmd->tvc_upages = kzalloc(sizeof(struct page *) *
1761                                        TCM_VHOST_PREALLOC_PAGES, GFP_KERNEL);
1762                if (!tv_cmd->tvc_upages) {
1763                        mutex_unlock(&tpg->tv_tpg_mutex);
1764                        pr_err("Unable to allocate tv_cmd->tvc_upages\n");
1765                        goto out;
1766                }
1767        }
1768        /*
1769         * Since we are running in 'demo mode' this call with generate a
1770         * struct se_node_acl for the tcm_vhost struct se_portal_group with
1771         * the SCSI Initiator port name of the passed configfs group 'name'.
1772         */
1773        tv_nexus->tvn_se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
1774                                se_tpg, (unsigned char *)name);
1775        if (!tv_nexus->tvn_se_sess->se_node_acl) {
1776                mutex_unlock(&tpg->tv_tpg_mutex);
1777                pr_debug("core_tpg_check_initiator_node_acl() failed"
1778                                " for %s\n", name);
1779                goto out;
1780        }
1781        /*
1782         * Now register the TCM vhost virtual I_T Nexus as active with the
1783         * call to __transport_register_session()
1784         */
1785        __transport_register_session(se_tpg, tv_nexus->tvn_se_sess->se_node_acl,
1786                        tv_nexus->tvn_se_sess, tv_nexus);
1787        tpg->tpg_nexus = tv_nexus;
1788
1789        mutex_unlock(&tpg->tv_tpg_mutex);
1790        return 0;
1791
1792out:
1793        tcm_vhost_free_cmd_map_res(tv_nexus, se_sess);
1794        transport_free_session(se_sess);
1795        kfree(tv_nexus);
1796        return -ENOMEM;
1797}
1798
1799static int tcm_vhost_drop_nexus(struct tcm_vhost_tpg *tpg)
1800{
1801        struct se_session *se_sess;
1802        struct tcm_vhost_nexus *tv_nexus;
1803
1804        mutex_lock(&tpg->tv_tpg_mutex);
1805        tv_nexus = tpg->tpg_nexus;
1806        if (!tv_nexus) {
1807                mutex_unlock(&tpg->tv_tpg_mutex);
1808                return -ENODEV;
1809        }
1810
1811        se_sess = tv_nexus->tvn_se_sess;
1812        if (!se_sess) {
1813                mutex_unlock(&tpg->tv_tpg_mutex);
1814                return -ENODEV;
1815        }
1816
1817        if (tpg->tv_tpg_port_count != 0) {
1818                mutex_unlock(&tpg->tv_tpg_mutex);
1819                pr_err("Unable to remove TCM_vhost I_T Nexus with"
1820                        " active TPG port count: %d\n",
1821                        tpg->tv_tpg_port_count);
1822                return -EBUSY;
1823        }
1824
1825        if (tpg->tv_tpg_vhost_count != 0) {
1826                mutex_unlock(&tpg->tv_tpg_mutex);
1827                pr_err("Unable to remove TCM_vhost I_T Nexus with"
1828                        " active TPG vhost count: %d\n",
1829                        tpg->tv_tpg_vhost_count);
1830                return -EBUSY;
1831        }
1832
1833        pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated"
1834                " %s Initiator Port: %s\n", tcm_vhost_dump_proto_id(tpg->tport),
1835                tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1836
1837        tcm_vhost_free_cmd_map_res(tv_nexus, se_sess);
1838        /*
1839         * Release the SCSI I_T Nexus to the emulated vhost Target Port
1840         */
1841        transport_deregister_session(tv_nexus->tvn_se_sess);
1842        tpg->tpg_nexus = NULL;
1843        mutex_unlock(&tpg->tv_tpg_mutex);
1844
1845        kfree(tv_nexus);
1846        return 0;
1847}
1848
1849static ssize_t tcm_vhost_tpg_show_nexus(struct se_portal_group *se_tpg,
1850                                        char *page)
1851{
1852        struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1853                                struct tcm_vhost_tpg, se_tpg);
1854        struct tcm_vhost_nexus *tv_nexus;
1855        ssize_t ret;
1856
1857        mutex_lock(&tpg->tv_tpg_mutex);
1858        tv_nexus = tpg->tpg_nexus;
1859        if (!tv_nexus) {
1860                mutex_unlock(&tpg->tv_tpg_mutex);
1861                return -ENODEV;
1862        }
1863        ret = snprintf(page, PAGE_SIZE, "%s\n",
1864                        tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1865        mutex_unlock(&tpg->tv_tpg_mutex);
1866
1867        return ret;
1868}
1869
1870static ssize_t tcm_vhost_tpg_store_nexus(struct se_portal_group *se_tpg,
1871                                         const char *page,
1872                                         size_t count)
1873{
1874        struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1875                                struct tcm_vhost_tpg, se_tpg);
1876        struct tcm_vhost_tport *tport_wwn = tpg->tport;
1877        unsigned char i_port[TCM_VHOST_NAMELEN], *ptr, *port_ptr;
1878        int ret;
1879        /*
1880         * Shutdown the active I_T nexus if 'NULL' is passed..
1881         */
1882        if (!strncmp(page, "NULL", 4)) {
1883                ret = tcm_vhost_drop_nexus(tpg);
1884                return (!ret) ? count : ret;
1885        }
1886        /*
1887         * Otherwise make sure the passed virtual Initiator port WWN matches
1888         * the fabric protocol_id set in tcm_vhost_make_tport(), and call
1889         * tcm_vhost_make_nexus().
1890         */
1891        if (strlen(page) >= TCM_VHOST_NAMELEN) {
1892                pr_err("Emulated NAA Sas Address: %s, exceeds"
1893                                " max: %d\n", page, TCM_VHOST_NAMELEN);
1894                return -EINVAL;
1895        }
1896        snprintf(&i_port[0], TCM_VHOST_NAMELEN, "%s", page);
1897
1898        ptr = strstr(i_port, "naa.");
1899        if (ptr) {
1900                if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
1901                        pr_err("Passed SAS Initiator Port %s does not"
1902                                " match target port protoid: %s\n", i_port,
1903                                tcm_vhost_dump_proto_id(tport_wwn));
1904                        return -EINVAL;
1905                }
1906                port_ptr = &i_port[0];
1907                goto check_newline;
1908        }
1909        ptr = strstr(i_port, "fc.");
1910        if (ptr) {
1911                if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
1912                        pr_err("Passed FCP Initiator Port %s does not"
1913                                " match target port protoid: %s\n", i_port,
1914                                tcm_vhost_dump_proto_id(tport_wwn));
1915                        return -EINVAL;
1916                }
1917                port_ptr = &i_port[3]; /* Skip over "fc." */
1918                goto check_newline;
1919        }
1920        ptr = strstr(i_port, "iqn.");
1921        if (ptr) {
1922                if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
1923                        pr_err("Passed iSCSI Initiator Port %s does not"
1924                                " match target port protoid: %s\n", i_port,
1925                                tcm_vhost_dump_proto_id(tport_wwn));
1926                        return -EINVAL;
1927                }
1928                port_ptr = &i_port[0];
1929                goto check_newline;
1930        }
1931        pr_err("Unable to locate prefix for emulated Initiator Port:"
1932                        " %s\n", i_port);
1933        return -EINVAL;
1934        /*
1935         * Clear any trailing newline for the NAA WWN
1936         */
1937check_newline:
1938        if (i_port[strlen(i_port)-1] == '\n')
1939                i_port[strlen(i_port)-1] = '\0';
1940
1941        ret = tcm_vhost_make_nexus(tpg, port_ptr);
1942        if (ret < 0)
1943                return ret;
1944
1945        return count;
1946}
1947
1948TF_TPG_BASE_ATTR(tcm_vhost, nexus, S_IRUGO | S_IWUSR);
1949
1950static struct configfs_attribute *tcm_vhost_tpg_attrs[] = {
1951        &tcm_vhost_tpg_nexus.attr,
1952        NULL,
1953};
1954
1955static struct se_portal_group *
1956tcm_vhost_make_tpg(struct se_wwn *wwn,
1957                   struct config_group *group,
1958                   const char *name)
1959{
1960        struct tcm_vhost_tport *tport = container_of(wwn,
1961                        struct tcm_vhost_tport, tport_wwn);
1962
1963        struct tcm_vhost_tpg *tpg;
1964        unsigned long tpgt;
1965        int ret;
1966
1967        if (strstr(name, "tpgt_") != name)
1968                return ERR_PTR(-EINVAL);
1969        if (kstrtoul(name + 5, 10, &tpgt) || tpgt > UINT_MAX)
1970                return ERR_PTR(-EINVAL);
1971
1972        tpg = kzalloc(sizeof(struct tcm_vhost_tpg), GFP_KERNEL);
1973        if (!tpg) {
1974                pr_err("Unable to allocate struct tcm_vhost_tpg");
1975                return ERR_PTR(-ENOMEM);
1976        }
1977        mutex_init(&tpg->tv_tpg_mutex);
1978        INIT_LIST_HEAD(&tpg->tv_tpg_list);
1979        tpg->tport = tport;
1980        tpg->tport_tpgt = tpgt;
1981
1982        ret = core_tpg_register(&tcm_vhost_fabric_configfs->tf_ops, wwn,
1983                                &tpg->se_tpg, tpg, TRANSPORT_TPG_TYPE_NORMAL);
1984        if (ret < 0) {
1985                kfree(tpg);
1986                return NULL;
1987        }
1988        mutex_lock(&tcm_vhost_mutex);
1989        list_add_tail(&tpg->tv_tpg_list, &tcm_vhost_list);
1990        mutex_unlock(&tcm_vhost_mutex);
1991
1992        return &tpg->se_tpg;
1993}
1994
1995static void tcm_vhost_drop_tpg(struct se_portal_group *se_tpg)
1996{
1997        struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1998                                struct tcm_vhost_tpg, se_tpg);
1999
2000        mutex_lock(&tcm_vhost_mutex);
2001        list_del(&tpg->tv_tpg_list);
2002        mutex_unlock(&tcm_vhost_mutex);
2003        /*
2004         * Release the virtual I_T Nexus for this vhost TPG
2005         */
2006        tcm_vhost_drop_nexus(tpg);
2007        /*
2008         * Deregister the se_tpg from TCM..
2009         */
2010        core_tpg_deregister(se_tpg);
2011        kfree(tpg);
2012}
2013
2014static struct se_wwn *
2015tcm_vhost_make_tport(struct target_fabric_configfs *tf,
2016                     struct config_group *group,
2017                     const char *name)
2018{
2019        struct tcm_vhost_tport *tport;
2020        char *ptr;
2021        u64 wwpn = 0;
2022        int off = 0;
2023
2024        /* if (tcm_vhost_parse_wwn(name, &wwpn, 1) < 0)
2025                return ERR_PTR(-EINVAL); */
2026
2027        tport = kzalloc(sizeof(struct tcm_vhost_tport), GFP_KERNEL);
2028        if (!tport) {
2029                pr_err("Unable to allocate struct tcm_vhost_tport");
2030                return ERR_PTR(-ENOMEM);
2031        }
2032        tport->tport_wwpn = wwpn;
2033        /*
2034         * Determine the emulated Protocol Identifier and Target Port Name
2035         * based on the incoming configfs directory name.
2036         */
2037        ptr = strstr(name, "naa.");
2038        if (ptr) {
2039                tport->tport_proto_id = SCSI_PROTOCOL_SAS;
2040                goto check_len;
2041        }
2042        ptr = strstr(name, "fc.");
2043        if (ptr) {
2044                tport->tport_proto_id = SCSI_PROTOCOL_FCP;
2045                off = 3; /* Skip over "fc." */
2046                goto check_len;
2047        }
2048        ptr = strstr(name, "iqn.");
2049        if (ptr) {
2050                tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
2051                goto check_len;
2052        }
2053
2054        pr_err("Unable to locate prefix for emulated Target Port:"
2055                        " %s\n", name);
2056        kfree(tport);
2057        return ERR_PTR(-EINVAL);
2058
2059check_len:
2060        if (strlen(name) >= TCM_VHOST_NAMELEN) {
2061                pr_err("Emulated %s Address: %s, exceeds"
2062                        " max: %d\n", name, tcm_vhost_dump_proto_id(tport),
2063                        TCM_VHOST_NAMELEN);
2064                kfree(tport);
2065                return ERR_PTR(-EINVAL);
2066        }
2067        snprintf(&tport->tport_name[0], TCM_VHOST_NAMELEN, "%s", &name[off]);
2068
2069        pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target"
2070                " %s Address: %s\n", tcm_vhost_dump_proto_id(tport), name);
2071
2072        return &tport->tport_wwn;
2073}
2074
2075static void tcm_vhost_drop_tport(struct se_wwn *wwn)
2076{
2077        struct tcm_vhost_tport *tport = container_of(wwn,
2078                                struct tcm_vhost_tport, tport_wwn);
2079
2080        pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target"
2081                " %s Address: %s\n", tcm_vhost_dump_proto_id(tport),
2082                tport->tport_name);
2083
2084        kfree(tport);
2085}
2086
2087static ssize_t
2088tcm_vhost_wwn_show_attr_version(struct target_fabric_configfs *tf,
2089                                char *page)
2090{
2091        return sprintf(page, "TCM_VHOST fabric module %s on %s/%s"
2092                "on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname,
2093                utsname()->machine);
2094}
2095
2096TF_WWN_ATTR_RO(tcm_vhost, version);
2097
2098static struct configfs_attribute *tcm_vhost_wwn_attrs[] = {
2099        &tcm_vhost_wwn_version.attr,
2100        NULL,
2101};
2102
2103static struct target_core_fabric_ops tcm_vhost_ops = {
2104        .get_fabric_name                = tcm_vhost_get_fabric_name,
2105        .get_fabric_proto_ident         = tcm_vhost_get_fabric_proto_ident,
2106        .tpg_get_wwn                    = tcm_vhost_get_fabric_wwn,
2107        .tpg_get_tag                    = tcm_vhost_get_tag,
2108        .tpg_get_default_depth          = tcm_vhost_get_default_depth,
2109        .tpg_get_pr_transport_id        = tcm_vhost_get_pr_transport_id,
2110        .tpg_get_pr_transport_id_len    = tcm_vhost_get_pr_transport_id_len,
2111        .tpg_parse_pr_out_transport_id  = tcm_vhost_parse_pr_out_transport_id,
2112        .tpg_check_demo_mode            = tcm_vhost_check_true,
2113        .tpg_check_demo_mode_cache      = tcm_vhost_check_true,
2114        .tpg_check_demo_mode_write_protect = tcm_vhost_check_false,
2115        .tpg_check_prod_mode_write_protect = tcm_vhost_check_false,
2116        .tpg_alloc_fabric_acl           = tcm_vhost_alloc_fabric_acl,
2117        .tpg_release_fabric_acl         = tcm_vhost_release_fabric_acl,
2118        .tpg_get_inst_index             = tcm_vhost_tpg_get_inst_index,
2119        .release_cmd                    = tcm_vhost_release_cmd,
2120        .check_stop_free                = vhost_scsi_check_stop_free,
2121        .shutdown_session               = tcm_vhost_shutdown_session,
2122        .close_session                  = tcm_vhost_close_session,
2123        .sess_get_index                 = tcm_vhost_sess_get_index,
2124        .sess_get_initiator_sid         = NULL,
2125        .write_pending                  = tcm_vhost_write_pending,
2126        .write_pending_status           = tcm_vhost_write_pending_status,
2127        .set_default_node_attributes    = tcm_vhost_set_default_node_attrs,
2128        .get_task_tag                   = tcm_vhost_get_task_tag,
2129        .get_cmd_state                  = tcm_vhost_get_cmd_state,
2130        .queue_data_in                  = tcm_vhost_queue_data_in,
2131        .queue_status                   = tcm_vhost_queue_status,
2132        .queue_tm_rsp                   = tcm_vhost_queue_tm_rsp,
2133        /*
2134         * Setup callers for generic logic in target_core_fabric_configfs.c
2135         */
2136        .fabric_make_wwn                = tcm_vhost_make_tport,
2137        .fabric_drop_wwn                = tcm_vhost_drop_tport,
2138        .fabric_make_tpg                = tcm_vhost_make_tpg,
2139        .fabric_drop_tpg                = tcm_vhost_drop_tpg,
2140        .fabric_post_link               = tcm_vhost_port_link,
2141        .fabric_pre_unlink              = tcm_vhost_port_unlink,
2142        .fabric_make_np                 = NULL,
2143        .fabric_drop_np                 = NULL,
2144        .fabric_make_nodeacl            = tcm_vhost_make_nodeacl,
2145        .fabric_drop_nodeacl            = tcm_vhost_drop_nodeacl,
2146};
2147
2148static int tcm_vhost_register_configfs(void)
2149{
2150        struct target_fabric_configfs *fabric;
2151        int ret;
2152
2153        pr_debug("TCM_VHOST fabric module %s on %s/%s"
2154                " on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname,
2155                utsname()->machine);
2156        /*
2157         * Register the top level struct config_item_type with TCM core
2158         */
2159        fabric = target_fabric_configfs_init(THIS_MODULE, "vhost");
2160        if (IS_ERR(fabric)) {
2161                pr_err("target_fabric_configfs_init() failed\n");
2162                return PTR_ERR(fabric);
2163        }
2164        /*
2165         * Setup fabric->tf_ops from our local tcm_vhost_ops
2166         */
2167        fabric->tf_ops = tcm_vhost_ops;
2168        /*
2169         * Setup default attribute lists for various fabric->tf_cit_tmpl
2170         */
2171        TF_CIT_TMPL(fabric)->tfc_wwn_cit.ct_attrs = tcm_vhost_wwn_attrs;
2172        TF_CIT_TMPL(fabric)->tfc_tpg_base_cit.ct_attrs = tcm_vhost_tpg_attrs;
2173        TF_CIT_TMPL(fabric)->tfc_tpg_attrib_cit.ct_attrs = NULL;
2174        TF_CIT_TMPL(fabric)->tfc_tpg_param_cit.ct_attrs = NULL;
2175        TF_CIT_TMPL(fabric)->tfc_tpg_np_base_cit.ct_attrs = NULL;
2176        TF_CIT_TMPL(fabric)->tfc_tpg_nacl_base_cit.ct_attrs = NULL;
2177        TF_CIT_TMPL(fabric)->tfc_tpg_nacl_attrib_cit.ct_attrs = NULL;
2178        TF_CIT_TMPL(fabric)->tfc_tpg_nacl_auth_cit.ct_attrs = NULL;
2179        TF_CIT_TMPL(fabric)->tfc_tpg_nacl_param_cit.ct_attrs = NULL;
2180        /*
2181         * Register the fabric for use within TCM
2182         */
2183        ret = target_fabric_configfs_register(fabric);
2184        if (ret < 0) {
2185                pr_err("target_fabric_configfs_register() failed"
2186                                " for TCM_VHOST\n");
2187                return ret;
2188        }
2189        /*
2190         * Setup our local pointer to *fabric
2191         */
2192        tcm_vhost_fabric_configfs = fabric;
2193        pr_debug("TCM_VHOST[0] - Set fabric -> tcm_vhost_fabric_configfs\n");
2194        return 0;
2195};
2196
2197static void tcm_vhost_deregister_configfs(void)
2198{
2199        if (!tcm_vhost_fabric_configfs)
2200                return;
2201
2202        target_fabric_configfs_deregister(tcm_vhost_fabric_configfs);
2203        tcm_vhost_fabric_configfs = NULL;
2204        pr_debug("TCM_VHOST[0] - Cleared tcm_vhost_fabric_configfs\n");
2205};
2206
2207static int __init tcm_vhost_init(void)
2208{
2209        int ret = -ENOMEM;
2210        /*
2211         * Use our own dedicated workqueue for submitting I/O into
2212         * target core to avoid contention within system_wq.
2213         */
2214        tcm_vhost_workqueue = alloc_workqueue("tcm_vhost", 0, 0);
2215        if (!tcm_vhost_workqueue)
2216                goto out;
2217
2218        ret = vhost_scsi_register();
2219        if (ret < 0)
2220                goto out_destroy_workqueue;
2221
2222        ret = tcm_vhost_register_configfs();
2223        if (ret < 0)
2224                goto out_vhost_scsi_deregister;
2225
2226        return 0;
2227
2228out_vhost_scsi_deregister:
2229        vhost_scsi_deregister();
2230out_destroy_workqueue:
2231        destroy_workqueue(tcm_vhost_workqueue);
2232out:
2233        return ret;
2234};
2235
2236static void tcm_vhost_exit(void)
2237{
2238        tcm_vhost_deregister_configfs();
2239        vhost_scsi_deregister();
2240        destroy_workqueue(tcm_vhost_workqueue);
2241};
2242
2243MODULE_DESCRIPTION("VHOST_SCSI series fabric driver");
2244MODULE_ALIAS("tcm_vhost");
2245MODULE_LICENSE("GPL");
2246module_init(tcm_vhost_init);
2247module_exit(tcm_vhost_exit);
2248
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