drivers/vhost/scsi.c

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