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/vmalloc.h>
  39 #include <linux/miscdevice.h>
  40 #include <asm/unaligned.h>
  41 #include <scsi/scsi_common.h>
  42 #include <scsi/scsi_proto.h>
  43 #include <target/target_core_base.h>
  44 #include <target/target_core_fabric.h>
  45 #include <linux/vhost.h>
  46 #include <linux/virtio_scsi.h>
  47 #include <linux/llist.h>
  48 #include <linux/bitmap.h>
  49
  50 #include "vhost.h"
  51
  52 #define VHOST_SCSI_VERSION  "v0.1"
  53 #define VHOST_SCSI_NAMELEN 256
  54 #define VHOST_SCSI_MAX_CDB_SIZE 32
  55 #define VHOST_SCSI_PREALLOC_SGLS 2048
  56 #define VHOST_SCSI_PREALLOC_UPAGES 2048
  57 #define VHOST_SCSI_PREALLOC_PROT_SGLS 2048
  58
  59 /* Max number of requests before requeueing the job.
  60  * Using this limit prevents one virtqueue from starving others with
  61  * request.
  62  */
  63 #define VHOST_SCSI_WEIGHT 256
  64
  65 struct vhost_scsi_inflight {
  66         /* Wait for the flush operation to finish */
  67         struct completion comp;
  68         /* Refcount for the inflight reqs */
  69         struct kref kref;
  70 };
  71
  72 struct vhost_scsi_cmd {
  73         /* Descriptor from vhost_get_vq_desc() for virt_queue segment */
  74         int tvc_vq_desc;
  75         /* virtio-scsi initiator task attribute */
  76         int tvc_task_attr;
  77         /* virtio-scsi response incoming iovecs */
  78         int tvc_in_iovs;
  79         /* virtio-scsi initiator data direction */
  80         enum dma_data_direction tvc_data_direction;
  81         /* Expected data transfer length from virtio-scsi header */
  82         u32 tvc_exp_data_len;
  83         /* The Tag from include/linux/virtio_scsi.h:struct virtio_scsi_cmd_req */
  84         u64 tvc_tag;
  85         /* The number of scatterlists associated with this cmd */
  86         u32 tvc_sgl_count;
  87         u32 tvc_prot_sgl_count;
  88         /* Saved unpacked SCSI LUN for vhost_scsi_submission_work() */
  89         u32 tvc_lun;
  90         /* Pointer to the SGL formatted memory from virtio-scsi */
  91         struct scatterlist *tvc_sgl;
  92         struct scatterlist *tvc_prot_sgl;
  93         struct page **tvc_upages;
  94         /* Pointer to response header iovec */
  95         struct iovec tvc_resp_iov;
  96         /* Pointer to vhost_scsi for our device */
  97         struct vhost_scsi *tvc_vhost;
  98         /* Pointer to vhost_virtqueue for the cmd */
  99         struct vhost_virtqueue *tvc_vq;
 100         /* Pointer to vhost nexus memory */
 101         struct vhost_scsi_nexus *tvc_nexus;
 102         /* The TCM I/O descriptor that is accessed via container_of() */
 103         struct se_cmd tvc_se_cmd;
 104         /* work item used for cmwq dispatch to vhost_scsi_submission_work() */
 105         struct work_struct work;
 106         /* Copy of the incoming SCSI command descriptor block (CDB) */
 107         unsigned char tvc_cdb[VHOST_SCSI_MAX_CDB_SIZE];
 108         /* Sense buffer that will be mapped into outgoing status */
 109         unsigned char tvc_sense_buf[TRANSPORT_SENSE_BUFFER];
 110         /* Completed commands list, serviced from vhost worker thread */
 111         struct llist_node tvc_completion_list;
 112         /* Used to track inflight cmd */
 113         struct vhost_scsi_inflight *inflight;
 114 };
 115
 116 struct vhost_scsi_nexus {
 117         /* Pointer to TCM session for I_T Nexus */
 118         struct se_session *tvn_se_sess;
 119 };
 120
 121 struct vhost_scsi_tpg {
 122         /* Vhost port target portal group tag for TCM */
 123         u16 tport_tpgt;
 124         /* Used to track number of TPG Port/Lun Links wrt to explict I_T Nexus shutdown */
 125         int tv_tpg_port_count;
 126         /* Used for vhost_scsi device reference to tpg_nexus, protected by tv_tpg_mutex */
 127         int tv_tpg_vhost_count;
 128         /* Used for enabling T10-PI with legacy devices */
 129         int tv_fabric_prot_type;
 130         /* list for vhost_scsi_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 vhost_scsi_nexus *tpg_nexus;
 136         /* Pointer back to vhost_scsi_tport */
 137         struct vhost_scsi_tport *tport;
 138         /* Returned by vhost_scsi_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         struct list_head tmf_queue;
 143 };
 144
 145 struct vhost_scsi_tport {
 146         /* SCSI protocol the tport is providing */
 147         u8 tport_proto_id;
 148         /* Binary World Wide unique Port Name for Vhost Target port */
 149         u64 tport_wwpn;
 150         /* ASCII formatted WWPN for Vhost Target port */
 151         char tport_name[VHOST_SCSI_NAMELEN];
 152         /* Returned by vhost_scsi_make_tport() */
 153         struct se_wwn tport_wwn;
 154 };
 155
 156 struct vhost_scsi_evt {
 157         /* event to be sent to guest */
 158         struct virtio_scsi_event event;
 159         /* event list, serviced from vhost worker thread */
 160         struct llist_node list;
 161 };
 162
 163 enum {
 164         VHOST_SCSI_VQ_CTL = 0,
 165         VHOST_SCSI_VQ_EVT = 1,
 166         VHOST_SCSI_VQ_IO = 2,
 167 };
 168
 169 /* Note: can't set VIRTIO_F_VERSION_1 yet, since that implies ANY_LAYOUT. */
 170 enum {
 171         VHOST_SCSI_FEATURES = VHOST_FEATURES | (1ULL << VIRTIO_SCSI_F_HOTPLUG) |
 172                                                (1ULL << VIRTIO_SCSI_F_T10_PI)
 173 };
 174
 175 #define VHOST_SCSI_MAX_TARGET   256
 176 #define VHOST_SCSI_MAX_VQ       128
 177 #define VHOST_SCSI_MAX_EVENT    128
 178
 179 struct vhost_scsi_virtqueue {
 180         struct vhost_virtqueue vq;
 181         /*
 182          * Reference counting for inflight reqs, used for flush operation. At
 183          * each time, one reference tracks new commands submitted, while we
 184          * wait for another one to reach 0.
 185          */
 186         struct vhost_scsi_inflight inflights[2];
 187         /*
 188          * Indicate current inflight in use, protected by vq->mutex.
 189          * Writers must also take dev mutex and flush under it.
 190          */
 191         int inflight_idx;
 192         struct vhost_scsi_cmd *scsi_cmds;
 193         struct sbitmap scsi_tags;
 194         int max_cmds;
 195 };
 196
 197 struct vhost_scsi {
 198         /* Protected by vhost_scsi->dev.mutex */
 199         struct vhost_scsi_tpg **vs_tpg;
 200         char vs_vhost_wwpn[TRANSPORT_IQN_LEN];
 201
 202         struct vhost_dev dev;
 203         struct vhost_scsi_virtqueue vqs[VHOST_SCSI_MAX_VQ];
 204
 205         struct vhost_work vs_completion_work; /* cmd completion work item */
 206         struct llist_head vs_completion_list; /* cmd completion queue */
 207
 208         struct vhost_work vs_event_work; /* evt injection work item */
 209         struct llist_head vs_event_list; /* evt injection queue */
 210
 211         bool vs_events_missed; /* any missed events, protected by vq->mutex */
 212         int vs_events_nr; /* num of pending events, protected by vq->mutex */
 213 };
 214
 215 struct vhost_scsi_tmf {
 216         struct vhost_work vwork;
 217         struct vhost_scsi_tpg *tpg;
 218         struct vhost_scsi *vhost;
 219         struct vhost_scsi_virtqueue *svq;
 220         struct list_head queue_entry;
 221
 222         struct se_cmd se_cmd;
 223         u8 scsi_resp;
 224         struct vhost_scsi_inflight *inflight;
 225         struct iovec resp_iov;
 226         int in_iovs;
 227         int vq_desc;
 228 };
 229
 230 /*
 231  * Context for processing request and control queue operations.
 232  */
 233 struct vhost_scsi_ctx {
 234         int head;
 235         unsigned int out, in;
 236         size_t req_size, rsp_size;
 237         size_t out_size, in_size;
 238         u8 *target, *lunp;
 239         void *req;
 240         struct iov_iter out_iter;
 241 };
 242
 243 static struct workqueue_struct *vhost_scsi_workqueue;
 244
 245 /* Global spinlock to protect vhost_scsi TPG list for vhost IOCTL access */
 246 static DEFINE_MUTEX(vhost_scsi_mutex);
 247 static LIST_HEAD(vhost_scsi_list);
 248
 249 static void vhost_scsi_done_inflight(struct kref *kref)
 250 {
 251         struct vhost_scsi_inflight *inflight;
 252
 253         inflight = container_of(kref, struct vhost_scsi_inflight, kref);
 254         complete(&inflight->comp);
 255 }
 256
 257 static void vhost_scsi_init_inflight(struct vhost_scsi *vs,
 258                                     struct vhost_scsi_inflight *old_inflight[])
 259 {
 260         struct vhost_scsi_inflight *new_inflight;
 261         struct vhost_virtqueue *vq;
 262         int idx, i;
 263
 264         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
 265                 vq = &vs->vqs[i].vq;
 266
 267                 mutex_lock(&vq->mutex);
 268
 269                 /* store old infight */
 270                 idx = vs->vqs[i].inflight_idx;
 271                 if (old_inflight)
 272                         old_inflight[i] = &vs->vqs[i].inflights[idx];
 273
 274                 /* setup new infight */
 275                 vs->vqs[i].inflight_idx = idx ^ 1;
 276                 new_inflight = &vs->vqs[i].inflights[idx ^ 1];
 277                 kref_init(&new_inflight->kref);
 278                 init_completion(&new_inflight->comp);
 279
 280                 mutex_unlock(&vq->mutex);
 281         }
 282 }
 283
 284 static struct vhost_scsi_inflight *
 285 vhost_scsi_get_inflight(struct vhost_virtqueue *vq)
 286 {
 287         struct vhost_scsi_inflight *inflight;
 288         struct vhost_scsi_virtqueue *svq;
 289
 290         svq = container_of(vq, struct vhost_scsi_virtqueue, vq);
 291         inflight = &svq->inflights[svq->inflight_idx];
 292         kref_get(&inflight->kref);
 293
 294         return inflight;
 295 }
 296
 297 static void vhost_scsi_put_inflight(struct vhost_scsi_inflight *inflight)
 298 {
 299         kref_put(&inflight->kref, vhost_scsi_done_inflight);
 300 }
 301
 302 static int vhost_scsi_check_true(struct se_portal_group *se_tpg)
 303 {
 304         return 1;
 305 }
 306
 307 static int vhost_scsi_check_false(struct se_portal_group *se_tpg)
 308 {
 309         return 0;
 310 }
 311
 312 static char *vhost_scsi_get_fabric_wwn(struct se_portal_group *se_tpg)
 313 {
 314         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 315                                 struct vhost_scsi_tpg, se_tpg);
 316         struct vhost_scsi_tport *tport = tpg->tport;
 317
 318         return &tport->tport_name[0];
 319 }
 320
 321 static u16 vhost_scsi_get_tpgt(struct se_portal_group *se_tpg)
 322 {
 323         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 324                                 struct vhost_scsi_tpg, se_tpg);
 325         return tpg->tport_tpgt;
 326 }
 327
 328 static int vhost_scsi_check_prot_fabric_only(struct se_portal_group *se_tpg)
 329 {
 330         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 331                                 struct vhost_scsi_tpg, se_tpg);
 332
 333         return tpg->tv_fabric_prot_type;
 334 }
 335
 336 static u32 vhost_scsi_tpg_get_inst_index(struct se_portal_group *se_tpg)
 337 {
 338         return 1;
 339 }
 340
 341 static void vhost_scsi_release_cmd_res(struct se_cmd *se_cmd)
 342 {
 343         struct vhost_scsi_cmd *tv_cmd = container_of(se_cmd,
 344                                 struct vhost_scsi_cmd, tvc_se_cmd);
 345         struct vhost_scsi_virtqueue *svq = container_of(tv_cmd->tvc_vq,
 346                                 struct vhost_scsi_virtqueue, vq);
 347         struct vhost_scsi_inflight *inflight = tv_cmd->inflight;
 348         int i;
 349
 350         if (tv_cmd->tvc_sgl_count) {
 351                 for (i = 0; i < tv_cmd->tvc_sgl_count; i++)
 352                         put_page(sg_page(&tv_cmd->tvc_sgl[i]));
 353         }
 354         if (tv_cmd->tvc_prot_sgl_count) {
 355                 for (i = 0; i < tv_cmd->tvc_prot_sgl_count; i++)
 356                         put_page(sg_page(&tv_cmd->tvc_prot_sgl[i]));
 357         }
 358
 359         sbitmap_clear_bit(&svq->scsi_tags, se_cmd->map_tag);
 360         vhost_scsi_put_inflight(inflight);
 361 }
 362
 363 static void vhost_scsi_release_tmf_res(struct vhost_scsi_tmf *tmf)
 364 {
 365         struct vhost_scsi_tpg *tpg = tmf->tpg;
 366         struct vhost_scsi_inflight *inflight = tmf->inflight;
 367
 368         mutex_lock(&tpg->tv_tpg_mutex);
 369         list_add_tail(&tpg->tmf_queue, &tmf->queue_entry);
 370         mutex_unlock(&tpg->tv_tpg_mutex);
 371         vhost_scsi_put_inflight(inflight);
 372 }
 373
 374 static void vhost_scsi_release_cmd(struct se_cmd *se_cmd)
 375 {
 376         if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB) {
 377                 struct vhost_scsi_tmf *tmf = container_of(se_cmd,
 378                                         struct vhost_scsi_tmf, se_cmd);
 379
 380                 vhost_work_queue(&tmf->vhost->dev, &tmf->vwork);
 381         } else {
 382                 struct vhost_scsi_cmd *cmd = container_of(se_cmd,
 383                                         struct vhost_scsi_cmd, tvc_se_cmd);
 384                 struct vhost_scsi *vs = cmd->tvc_vhost;
 385
 386                 llist_add(&cmd->tvc_completion_list, &vs->vs_completion_list);
 387                 vhost_work_queue(&vs->dev, &vs->vs_completion_work);
 388         }
 389 }
 390
 391 static u32 vhost_scsi_sess_get_index(struct se_session *se_sess)
 392 {
 393         return 0;
 394 }
 395
 396 static int vhost_scsi_write_pending(struct se_cmd *se_cmd)
 397 {
 398         /* Go ahead and process the write immediately */
 399         target_execute_cmd(se_cmd);
 400         return 0;
 401 }
 402
 403 static void vhost_scsi_set_default_node_attrs(struct se_node_acl *nacl)
 404 {
 405         return;
 406 }
 407
 408 static int vhost_scsi_get_cmd_state(struct se_cmd *se_cmd)
 409 {
 410         return 0;
 411 }
 412
 413 static int vhost_scsi_queue_data_in(struct se_cmd *se_cmd)
 414 {
 415         transport_generic_free_cmd(se_cmd, 0);
 416         return 0;
 417 }
 418
 419 static int vhost_scsi_queue_status(struct se_cmd *se_cmd)
 420 {
 421         transport_generic_free_cmd(se_cmd, 0);
 422         return 0;
 423 }
 424
 425 static void vhost_scsi_queue_tm_rsp(struct se_cmd *se_cmd)
 426 {
 427         struct vhost_scsi_tmf *tmf = container_of(se_cmd, struct vhost_scsi_tmf,
 428                                                   se_cmd);
 429
 430         tmf->scsi_resp = se_cmd->se_tmr_req->response;
 431         transport_generic_free_cmd(&tmf->se_cmd, 0);
 432 }
 433
 434 static void vhost_scsi_aborted_task(struct se_cmd *se_cmd)
 435 {
 436         return;
 437 }
 438
 439 static void vhost_scsi_free_evt(struct vhost_scsi *vs, struct vhost_scsi_evt *evt)
 440 {
 441         vs->vs_events_nr--;
 442         kfree(evt);
 443 }
 444
 445 static struct vhost_scsi_evt *
 446 vhost_scsi_allocate_evt(struct vhost_scsi *vs,
 447                        u32 event, u32 reason)
 448 {
 449         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 450         struct vhost_scsi_evt *evt;
 451
 452         if (vs->vs_events_nr > VHOST_SCSI_MAX_EVENT) {
 453                 vs->vs_events_missed = true;
 454                 return NULL;
 455         }
 456
 457         evt = kzalloc(sizeof(*evt), GFP_KERNEL);
 458         if (!evt) {
 459                 vq_err(vq, "Failed to allocate vhost_scsi_evt\n");
 460                 vs->vs_events_missed = true;
 461                 return NULL;
 462         }
 463
 464         evt->event.event = cpu_to_vhost32(vq, event);
 465         evt->event.reason = cpu_to_vhost32(vq, reason);
 466         vs->vs_events_nr++;
 467
 468         return evt;
 469 }
 470
 471 static int vhost_scsi_check_stop_free(struct se_cmd *se_cmd)
 472 {
 473         return target_put_sess_cmd(se_cmd);
 474 }
 475
 476 static void
 477 vhost_scsi_do_evt_work(struct vhost_scsi *vs, struct vhost_scsi_evt *evt)
 478 {
 479         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 480         struct virtio_scsi_event *event = &evt->event;
 481         struct virtio_scsi_event __user *eventp;
 482         unsigned out, in;
 483         int head, ret;
 484
 485         if (!vhost_vq_get_backend(vq)) {
 486                 vs->vs_events_missed = true;
 487                 return;
 488         }
 489
 490 again:
 491         vhost_disable_notify(&vs->dev, vq);
 492         head = vhost_get_vq_desc(vq, vq->iov,
 493                         ARRAY_SIZE(vq->iov), &out, &in,
 494                         NULL, NULL);
 495         if (head < 0) {
 496                 vs->vs_events_missed = true;
 497                 return;
 498         }
 499         if (head == vq->num) {
 500                 if (vhost_enable_notify(&vs->dev, vq))
 501                         goto again;
 502                 vs->vs_events_missed = true;
 503                 return;
 504         }
 505
 506         if ((vq->iov[out].iov_len != sizeof(struct virtio_scsi_event))) {
 507                 vq_err(vq, "Expecting virtio_scsi_event, got %zu bytes\n",
 508                                 vq->iov[out].iov_len);
 509                 vs->vs_events_missed = true;
 510                 return;
 511         }
 512
 513         if (vs->vs_events_missed) {
 514                 event->event |= cpu_to_vhost32(vq, VIRTIO_SCSI_T_EVENTS_MISSED);
 515                 vs->vs_events_missed = false;
 516         }
 517
 518         eventp = vq->iov[out].iov_base;
 519         ret = __copy_to_user(eventp, event, sizeof(*event));
 520         if (!ret)
 521                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 522         else
 523                 vq_err(vq, "Faulted on vhost_scsi_send_event\n");
 524 }
 525
 526 static void vhost_scsi_evt_work(struct vhost_work *work)
 527 {
 528         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 529                                         vs_event_work);
 530         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 531         struct vhost_scsi_evt *evt, *t;
 532         struct llist_node *llnode;
 533
 534         mutex_lock(&vq->mutex);
 535         llnode = llist_del_all(&vs->vs_event_list);
 536         llist_for_each_entry_safe(evt, t, llnode, list) {
 537                 vhost_scsi_do_evt_work(vs, evt);
 538                 vhost_scsi_free_evt(vs, evt);
 539         }
 540         mutex_unlock(&vq->mutex);
 541 }
 542
 543 /* Fill in status and signal that we are done processing this command
 544  *
 545  * This is scheduled in the vhost work queue so we are called with the owner
 546  * process mm and can access the vring.
 547  */
 548 static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
 549 {
 550         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 551                                         vs_completion_work);
 552         DECLARE_BITMAP(signal, VHOST_SCSI_MAX_VQ);
 553         struct virtio_scsi_cmd_resp v_rsp;
 554         struct vhost_scsi_cmd *cmd, *t;
 555         struct llist_node *llnode;
 556         struct se_cmd *se_cmd;
 557         struct iov_iter iov_iter;
 558         int ret, vq;
 559
 560         bitmap_zero(signal, VHOST_SCSI_MAX_VQ);
 561         llnode = llist_del_all(&vs->vs_completion_list);
 562         llist_for_each_entry_safe(cmd, t, llnode, tvc_completion_list) {
 563                 se_cmd = &cmd->tvc_se_cmd;
 564
 565                 pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__,
 566                         cmd, se_cmd->residual_count, se_cmd->scsi_status);
 567
 568                 memset(&v_rsp, 0, sizeof(v_rsp));
 569                 v_rsp.resid = cpu_to_vhost32(cmd->tvc_vq, se_cmd->residual_count);
 570                 /* TODO is status_qualifier field needed? */
 571                 v_rsp.status = se_cmd->scsi_status;
 572                 v_rsp.sense_len = cpu_to_vhost32(cmd->tvc_vq,
 573                                                  se_cmd->scsi_sense_length);
 574                 memcpy(v_rsp.sense, cmd->tvc_sense_buf,
 575                        se_cmd->scsi_sense_length);
 576
 577                 iov_iter_init(&iov_iter, READ, &cmd->tvc_resp_iov,
 578                               cmd->tvc_in_iovs, sizeof(v_rsp));
 579                 ret = copy_to_iter(&v_rsp, sizeof(v_rsp), &iov_iter);
 580                 if (likely(ret == sizeof(v_rsp))) {
 581                         struct vhost_scsi_virtqueue *q;
 582                         vhost_add_used(cmd->tvc_vq, cmd->tvc_vq_desc, 0);
 583                         q = container_of(cmd->tvc_vq, struct vhost_scsi_virtqueue, vq);
 584                         vq = q - vs->vqs;
 585                         __set_bit(vq, signal);
 586                 } else
 587                         pr_err("Faulted on virtio_scsi_cmd_resp\n");
 588
 589                 vhost_scsi_release_cmd_res(se_cmd);
 590         }
 591
 592         vq = -1;
 593         while ((vq = find_next_bit(signal, VHOST_SCSI_MAX_VQ, vq + 1))
 594                 < VHOST_SCSI_MAX_VQ)
 595                 vhost_signal(&vs->dev, &vs->vqs[vq].vq);
 596 }
 597
 598 static struct vhost_scsi_cmd *
 599 vhost_scsi_get_cmd(struct vhost_virtqueue *vq, struct vhost_scsi_tpg *tpg,
 600                    unsigned char *cdb, u64 scsi_tag, u16 lun, u8 task_attr,
 601                    u32 exp_data_len, int data_direction)
 602 {
 603         struct vhost_scsi_virtqueue *svq = container_of(vq,
 604                                         struct vhost_scsi_virtqueue, vq);
 605         struct vhost_scsi_cmd *cmd;
 606         struct vhost_scsi_nexus *tv_nexus;
 607         struct scatterlist *sg, *prot_sg;
 608         struct page **pages;
 609         int tag;
 610
 611         tv_nexus = tpg->tpg_nexus;
 612         if (!tv_nexus) {
 613                 pr_err("Unable to locate active struct vhost_scsi_nexus\n");
 614                 return ERR_PTR(-EIO);
 615         }
 616
 617         tag = sbitmap_get(&svq->scsi_tags, 0, false);
 618         if (tag < 0) {
 619                 pr_err("Unable to obtain tag for vhost_scsi_cmd\n");
 620                 return ERR_PTR(-ENOMEM);
 621         }
 622
 623         cmd = &svq->scsi_cmds[tag];
 624         sg = cmd->tvc_sgl;
 625         prot_sg = cmd->tvc_prot_sgl;
 626         pages = cmd->tvc_upages;
 627         memset(cmd, 0, sizeof(*cmd));
 628         cmd->tvc_sgl = sg;
 629         cmd->tvc_prot_sgl = prot_sg;
 630         cmd->tvc_upages = pages;
 631         cmd->tvc_se_cmd.map_tag = tag;
 632         cmd->tvc_tag = scsi_tag;
 633         cmd->tvc_lun = lun;
 634         cmd->tvc_task_attr = task_attr;
 635         cmd->tvc_exp_data_len = exp_data_len;
 636         cmd->tvc_data_direction = data_direction;
 637         cmd->tvc_nexus = tv_nexus;
 638         cmd->inflight = vhost_scsi_get_inflight(vq);
 639
 640         memcpy(cmd->tvc_cdb, cdb, VHOST_SCSI_MAX_CDB_SIZE);
 641
 642         return cmd;
 643 }
 644
 645 /*
 646  * Map a user memory range into a scatterlist
 647  *
 648  * Returns the number of scatterlist entries used or -errno on error.
 649  */
 650 static int
 651 vhost_scsi_map_to_sgl(struct vhost_scsi_cmd *cmd,
 652                       struct iov_iter *iter,
 653                       struct scatterlist *sgl,
 654                       bool write)
 655 {
 656         struct page **pages = cmd->tvc_upages;
 657         struct scatterlist *sg = sgl;
 658         ssize_t bytes;
 659         size_t offset;
 660         unsigned int npages = 0;
 661
 662         bytes = iov_iter_get_pages(iter, pages, LONG_MAX,
 663                                 VHOST_SCSI_PREALLOC_UPAGES, &offset);
 664         /* No pages were pinned */
 665         if (bytes <= 0)
 666                 return bytes < 0 ? bytes : -EFAULT;
 667
 668         iov_iter_advance(iter, bytes);
 669
 670         while (bytes) {
 671                 unsigned n = min_t(unsigned, PAGE_SIZE - offset, bytes);
 672                 sg_set_page(sg++, pages[npages++], n, offset);
 673                 bytes -= n;
 674                 offset = 0;
 675         }
 676         return npages;
 677 }
 678
 679 static int
 680 vhost_scsi_calc_sgls(struct iov_iter *iter, size_t bytes, int max_sgls)
 681 {
 682         int sgl_count = 0;
 683
 684         if (!iter || !iter->iov) {
 685                 pr_err("%s: iter->iov is NULL, but expected bytes: %zu"
 686                        " present\n", __func__, bytes);
 687                 return -EINVAL;
 688         }
 689
 690         sgl_count = iov_iter_npages(iter, 0xffff);
 691         if (sgl_count > max_sgls) {
 692                 pr_err("%s: requested sgl_count: %d exceeds pre-allocated"
 693                        " max_sgls: %d\n", __func__, sgl_count, max_sgls);
 694                 return -EINVAL;
 695         }
 696         return sgl_count;
 697 }
 698
 699 static int
 700 vhost_scsi_iov_to_sgl(struct vhost_scsi_cmd *cmd, bool write,
 701                       struct iov_iter *iter,
 702                       struct scatterlist *sg, int sg_count)
 703 {
 704         struct scatterlist *p = sg;
 705         int ret;
 706
 707         while (iov_iter_count(iter)) {
 708                 ret = vhost_scsi_map_to_sgl(cmd, iter, sg, write);
 709                 if (ret < 0) {
 710                         while (p < sg) {
 711                                 struct page *page = sg_page(p++);
 712                                 if (page)
 713                                         put_page(page);
 714                         }
 715                         return ret;
 716                 }
 717                 sg += ret;
 718         }
 719         return 0;
 720 }
 721
 722 static int
 723 vhost_scsi_mapal(struct vhost_scsi_cmd *cmd,
 724                  size_t prot_bytes, struct iov_iter *prot_iter,
 725                  size_t data_bytes, struct iov_iter *data_iter)
 726 {
 727         int sgl_count, ret;
 728         bool write = (cmd->tvc_data_direction == DMA_FROM_DEVICE);
 729
 730         if (prot_bytes) {
 731                 sgl_count = vhost_scsi_calc_sgls(prot_iter, prot_bytes,
 732                                                  VHOST_SCSI_PREALLOC_PROT_SGLS);
 733                 if (sgl_count < 0)
 734                         return sgl_count;
 735
 736                 sg_init_table(cmd->tvc_prot_sgl, sgl_count);
 737                 cmd->tvc_prot_sgl_count = sgl_count;
 738                 pr_debug("%s prot_sg %p prot_sgl_count %u\n", __func__,
 739                          cmd->tvc_prot_sgl, cmd->tvc_prot_sgl_count);
 740
 741                 ret = vhost_scsi_iov_to_sgl(cmd, write, prot_iter,
 742                                             cmd->tvc_prot_sgl,
 743                                             cmd->tvc_prot_sgl_count);
 744                 if (ret < 0) {
 745                         cmd->tvc_prot_sgl_count = 0;
 746                         return ret;
 747                 }
 748         }
 749         sgl_count = vhost_scsi_calc_sgls(data_iter, data_bytes,
 750                                          VHOST_SCSI_PREALLOC_SGLS);
 751         if (sgl_count < 0)
 752                 return sgl_count;
 753
 754         sg_init_table(cmd->tvc_sgl, sgl_count);
 755         cmd->tvc_sgl_count = sgl_count;
 756         pr_debug("%s data_sg %p data_sgl_count %u\n", __func__,
 757                   cmd->tvc_sgl, cmd->tvc_sgl_count);
 758
 759         ret = vhost_scsi_iov_to_sgl(cmd, write, data_iter,
 760                                     cmd->tvc_sgl, cmd->tvc_sgl_count);
 761         if (ret < 0) {
 762                 cmd->tvc_sgl_count = 0;
 763                 return ret;
 764         }
 765         return 0;
 766 }
 767
 768 static int vhost_scsi_to_tcm_attr(int attr)
 769 {
 770         switch (attr) {
 771         case VIRTIO_SCSI_S_SIMPLE:
 772                 return TCM_SIMPLE_TAG;
 773         case VIRTIO_SCSI_S_ORDERED:
 774                 return TCM_ORDERED_TAG;
 775         case VIRTIO_SCSI_S_HEAD:
 776                 return TCM_HEAD_TAG;
 777         case VIRTIO_SCSI_S_ACA:
 778                 return TCM_ACA_TAG;
 779         default:
 780                 break;
 781         }
 782         return TCM_SIMPLE_TAG;
 783 }
 784
 785 static void vhost_scsi_submission_work(struct work_struct *work)
 786 {
 787         struct vhost_scsi_cmd *cmd =
 788                 container_of(work, struct vhost_scsi_cmd, work);
 789         struct vhost_scsi_nexus *tv_nexus;
 790         struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
 791         struct scatterlist *sg_ptr, *sg_prot_ptr = NULL;
 792         int rc;
 793
 794         /* FIXME: BIDI operation */
 795         if (cmd->tvc_sgl_count) {
 796                 sg_ptr = cmd->tvc_sgl;
 797
 798                 if (cmd->tvc_prot_sgl_count)
 799                         sg_prot_ptr = cmd->tvc_prot_sgl;
 800                 else
 801                         se_cmd->prot_pto = true;
 802         } else {
 803                 sg_ptr = NULL;
 804         }
 805         tv_nexus = cmd->tvc_nexus;
 806
 807         se_cmd->tag = 0;
 808         rc = target_submit_cmd_map_sgls(se_cmd, tv_nexus->tvn_se_sess,
 809                         cmd->tvc_cdb, &cmd->tvc_sense_buf[0],
 810                         cmd->tvc_lun, cmd->tvc_exp_data_len,
 811                         vhost_scsi_to_tcm_attr(cmd->tvc_task_attr),
 812                         cmd->tvc_data_direction, TARGET_SCF_ACK_KREF,
 813                         sg_ptr, cmd->tvc_sgl_count, NULL, 0, sg_prot_ptr,
 814                         cmd->tvc_prot_sgl_count);
 815         if (rc < 0) {
 816                 transport_send_check_condition_and_sense(se_cmd,
 817                                 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
 818                 transport_generic_free_cmd(se_cmd, 0);
 819         }
 820 }
 821
 822 static void
 823 vhost_scsi_send_bad_target(struct vhost_scsi *vs,
 824                            struct vhost_virtqueue *vq,
 825                            int head, unsigned out)
 826 {
 827         struct virtio_scsi_cmd_resp __user *resp;
 828         struct virtio_scsi_cmd_resp rsp;
 829         int ret;
 830
 831         memset(&rsp, 0, sizeof(rsp));
 832         rsp.response = VIRTIO_SCSI_S_BAD_TARGET;
 833         resp = vq->iov[out].iov_base;
 834         ret = __copy_to_user(resp, &rsp, sizeof(rsp));
 835         if (!ret)
 836                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 837         else
 838                 pr_err("Faulted on virtio_scsi_cmd_resp\n");
 839 }
 840
 841 static int
 842 vhost_scsi_get_desc(struct vhost_scsi *vs, struct vhost_virtqueue *vq,
 843                     struct vhost_scsi_ctx *vc)
 844 {
 845         int ret = -ENXIO;
 846
 847         vc->head = vhost_get_vq_desc(vq, vq->iov,
 848                                      ARRAY_SIZE(vq->iov), &vc->out, &vc->in,
 849                                      NULL, NULL);
 850
 851         pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n",
 852                  vc->head, vc->out, vc->in);
 853
 854         /* On error, stop handling until the next kick. */
 855         if (unlikely(vc->head < 0))
 856                 goto done;
 857
 858         /* Nothing new?  Wait for eventfd to tell us they refilled. */
 859         if (vc->head == vq->num) {
 860                 if (unlikely(vhost_enable_notify(&vs->dev, vq))) {
 861                         vhost_disable_notify(&vs->dev, vq);
 862                         ret = -EAGAIN;
 863                 }
 864                 goto done;
 865         }
 866
 867         /*
 868          * Get the size of request and response buffers.
 869          * FIXME: Not correct for BIDI operation
 870          */
 871         vc->out_size = iov_length(vq->iov, vc->out);
 872         vc->in_size = iov_length(&vq->iov[vc->out], vc->in);
 873
 874         /*
 875          * Copy over the virtio-scsi request header, which for a
 876          * ANY_LAYOUT enabled guest may span multiple iovecs, or a
 877          * single iovec may contain both the header + outgoing
 878          * WRITE payloads.
 879          *
 880          * copy_from_iter() will advance out_iter, so that it will
 881          * point at the start of the outgoing WRITE payload, if
 882          * DMA_TO_DEVICE is set.
 883          */
 884         iov_iter_init(&vc->out_iter, WRITE, vq->iov, vc->out, vc->out_size);
 885         ret = 0;
 886
 887 done:
 888         return ret;
 889 }
 890
 891 static int
 892 vhost_scsi_chk_size(struct vhost_virtqueue *vq, struct vhost_scsi_ctx *vc)
 893 {
 894         if (unlikely(vc->in_size < vc->rsp_size)) {
 895                 vq_err(vq,
 896                        "Response buf too small, need min %zu bytes got %zu",
 897                        vc->rsp_size, vc->in_size);
 898                 return -EINVAL;
 899         } else if (unlikely(vc->out_size < vc->req_size)) {
 900                 vq_err(vq,
 901                        "Request buf too small, need min %zu bytes got %zu",
 902                        vc->req_size, vc->out_size);
 903                 return -EIO;
 904         }
 905
 906         return 0;
 907 }
 908
 909 static int
 910 vhost_scsi_get_req(struct vhost_virtqueue *vq, struct vhost_scsi_ctx *vc,
 911                    struct vhost_scsi_tpg **tpgp)
 912 {
 913         int ret = -EIO;
 914
 915         if (unlikely(!copy_from_iter_full(vc->req, vc->req_size,
 916                                           &vc->out_iter))) {
 917                 vq_err(vq, "Faulted on copy_from_iter_full\n");
 918         } else if (unlikely(*vc->lunp != 1)) {
 919                 /* virtio-scsi spec requires byte 0 of the lun to be 1 */
 920                 vq_err(vq, "Illegal virtio-scsi lun: %u\n", *vc->lunp);
 921         } else {
 922                 struct vhost_scsi_tpg **vs_tpg, *tpg;
 923
 924                 vs_tpg = vhost_vq_get_backend(vq);      /* validated at handler entry */
 925
 926                 tpg = READ_ONCE(vs_tpg[*vc->target]);
 927                 if (unlikely(!tpg)) {
 928                         vq_err(vq, "Target 0x%x does not exist\n", *vc->target);
 929                 } else {
 930                         if (tpgp)
 931                                 *tpgp = tpg;
 932                         ret = 0;
 933                 }
 934         }
 935
 936         return ret;
 937 }
 938
 939 static u16 vhost_buf_to_lun(u8 *lun_buf)
 940 {
 941         return ((lun_buf[2] << 8) | lun_buf[3]) & 0x3FFF;
 942 }
 943
 944 static void
 945 vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
 946 {
 947         struct vhost_scsi_tpg **vs_tpg, *tpg;
 948         struct virtio_scsi_cmd_req v_req;
 949         struct virtio_scsi_cmd_req_pi v_req_pi;
 950         struct vhost_scsi_ctx vc;
 951         struct vhost_scsi_cmd *cmd;
 952         struct iov_iter in_iter, prot_iter, data_iter;
 953         u64 tag;
 954         u32 exp_data_len, data_direction;
 955         int ret, prot_bytes, c = 0;
 956         u16 lun;
 957         u8 task_attr;
 958         bool t10_pi = vhost_has_feature(vq, VIRTIO_SCSI_F_T10_PI);
 959         void *cdb;
 960
 961         mutex_lock(&vq->mutex);
 962         /*
 963          * We can handle the vq only after the endpoint is setup by calling the
 964          * VHOST_SCSI_SET_ENDPOINT ioctl.
 965          */
 966         vs_tpg = vhost_vq_get_backend(vq);
 967         if (!vs_tpg)
 968                 goto out;
 969
 970         memset(&vc, 0, sizeof(vc));
 971         vc.rsp_size = sizeof(struct virtio_scsi_cmd_resp);
 972
 973         vhost_disable_notify(&vs->dev, vq);
 974
 975         do {
 976                 ret = vhost_scsi_get_desc(vs, vq, &vc);
 977                 if (ret)
 978                         goto err;
 979
 980                 /*
 981                  * Setup pointers and values based upon different virtio-scsi
 982                  * request header if T10_PI is enabled in KVM guest.
 983                  */
 984                 if (t10_pi) {
 985                         vc.req = &v_req_pi;
 986                         vc.req_size = sizeof(v_req_pi);
 987                         vc.lunp = &v_req_pi.lun[0];
 988                         vc.target = &v_req_pi.lun[1];
 989                 } else {
 990                         vc.req = &v_req;
 991                         vc.req_size = sizeof(v_req);
 992                         vc.lunp = &v_req.lun[0];
 993                         vc.target = &v_req.lun[1];
 994                 }
 995
 996                 /*
 997                  * Validate the size of request and response buffers.
 998                  * Check for a sane response buffer so we can report
 999                  * early errors back to the guest.
1000                  */
1001                 ret = vhost_scsi_chk_size(vq, &vc);
1002                 if (ret)
1003                         goto err;
1004
1005                 ret = vhost_scsi_get_req(vq, &vc, &tpg);
1006                 if (ret)
1007                         goto err;
1008
1009                 ret = -EIO;     /* bad target on any error from here on */
1010
1011                 /*
1012                  * Determine data_direction by calculating the total outgoing
1013                  * iovec sizes + incoming iovec sizes vs. virtio-scsi request +
1014                  * response headers respectively.
1015                  *
1016                  * For DMA_TO_DEVICE this is out_iter, which is already pointing
1017                  * to the right place.
1018                  *
1019                  * For DMA_FROM_DEVICE, the iovec will be just past the end
1020                  * of the virtio-scsi response header in either the same
1021                  * or immediately following iovec.
1022                  *
1023                  * Any associated T10_PI bytes for the outgoing / incoming
1024                  * payloads are included in calculation of exp_data_len here.
1025                  */
1026                 prot_bytes = 0;
1027
1028                 if (vc.out_size > vc.req_size) {
1029                         data_direction = DMA_TO_DEVICE;
1030                         exp_data_len = vc.out_size - vc.req_size;
1031                         data_iter = vc.out_iter;
1032                 } else if (vc.in_size > vc.rsp_size) {
1033                         data_direction = DMA_FROM_DEVICE;
1034                         exp_data_len = vc.in_size - vc.rsp_size;
1035
1036                         iov_iter_init(&in_iter, READ, &vq->iov[vc.out], vc.in,
1037                                       vc.rsp_size + exp_data_len);
1038                         iov_iter_advance(&in_iter, vc.rsp_size);
1039                         data_iter = in_iter;
1040                 } else {
1041                         data_direction = DMA_NONE;
1042                         exp_data_len = 0;
1043                 }
1044                 /*
1045                  * If T10_PI header + payload is present, setup prot_iter values
1046                  * and recalculate data_iter for vhost_scsi_mapal() mapping to
1047                  * host scatterlists via get_user_pages_fast().
1048                  */
1049                 if (t10_pi) {
1050                         if (v_req_pi.pi_bytesout) {
1051                                 if (data_direction != DMA_TO_DEVICE) {
1052                                         vq_err(vq, "Received non zero pi_bytesout,"
1053                                                 " but wrong data_direction\n");
1054                                         goto err;
1055                                 }
1056                                 prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesout);
1057                         } else if (v_req_pi.pi_bytesin) {
1058                                 if (data_direction != DMA_FROM_DEVICE) {
1059                                         vq_err(vq, "Received non zero pi_bytesin,"
1060                                                 " but wrong data_direction\n");
1061                                         goto err;
1062                                 }
1063                                 prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesin);
1064                         }
1065                         /*
1066                          * Set prot_iter to data_iter and truncate it to
1067                          * prot_bytes, and advance data_iter past any
1068                          * preceeding prot_bytes that may be present.
1069                          *
1070                          * Also fix up the exp_data_len to reflect only the
1071                          * actual data payload length.
1072                          */
1073                         if (prot_bytes) {
1074                                 exp_data_len -= prot_bytes;
1075                                 prot_iter = data_iter;
1076                                 iov_iter_truncate(&prot_iter, prot_bytes);
1077                                 iov_iter_advance(&data_iter, prot_bytes);
1078                         }
1079                         tag = vhost64_to_cpu(vq, v_req_pi.tag);
1080                         task_attr = v_req_pi.task_attr;
1081                         cdb = &v_req_pi.cdb[0];
1082                         lun = vhost_buf_to_lun(v_req_pi.lun);
1083                 } else {
1084                         tag = vhost64_to_cpu(vq, v_req.tag);
1085                         task_attr = v_req.task_attr;
1086                         cdb = &v_req.cdb[0];
1087                         lun = vhost_buf_to_lun(v_req.lun);
1088                 }
1089                 /*
1090                  * Check that the received CDB size does not exceeded our
1091                  * hardcoded max for vhost-scsi, then get a pre-allocated
1092                  * cmd descriptor for the new virtio-scsi tag.
1093                  *
1094                  * TODO what if cdb was too small for varlen cdb header?
1095                  */
1096                 if (unlikely(scsi_command_size(cdb) > VHOST_SCSI_MAX_CDB_SIZE)) {
1097                         vq_err(vq, "Received SCSI CDB with command_size: %d that"
1098                                 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1099                                 scsi_command_size(cdb), VHOST_SCSI_MAX_CDB_SIZE);
1100                                 goto err;
1101                 }
1102                 cmd = vhost_scsi_get_cmd(vq, tpg, cdb, tag, lun, task_attr,
1103                                          exp_data_len + prot_bytes,
1104                                          data_direction);
1105                 if (IS_ERR(cmd)) {
1106                         vq_err(vq, "vhost_scsi_get_cmd failed %ld\n",
1107                                PTR_ERR(cmd));
1108                         goto err;
1109                 }
1110                 cmd->tvc_vhost = vs;
1111                 cmd->tvc_vq = vq;
1112                 cmd->tvc_resp_iov = vq->iov[vc.out];
1113                 cmd->tvc_in_iovs = vc.in;
1114
1115                 pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n",
1116                          cmd->tvc_cdb[0], cmd->tvc_lun);
1117                 pr_debug("cmd: %p exp_data_len: %d, prot_bytes: %d data_direction:"
1118                          " %d\n", cmd, exp_data_len, prot_bytes, data_direction);
1119
1120                 if (data_direction != DMA_NONE) {
1121                         if (unlikely(vhost_scsi_mapal(cmd, prot_bytes,
1122                                                       &prot_iter, exp_data_len,
1123                                                       &data_iter))) {
1124                                 vq_err(vq, "Failed to map iov to sgl\n");
1125                                 vhost_scsi_release_cmd_res(&cmd->tvc_se_cmd);
1126                                 goto err;
1127                         }
1128                 }
1129                 /*
1130                  * Save the descriptor from vhost_get_vq_desc() to be used to
1131                  * complete the virtio-scsi request in TCM callback context via
1132                  * vhost_scsi_queue_data_in() and vhost_scsi_queue_status()
1133                  */
1134                 cmd->tvc_vq_desc = vc.head;
1135                 /*
1136                  * Dispatch cmd descriptor for cmwq execution in process
1137                  * context provided by vhost_scsi_workqueue.  This also ensures
1138                  * cmd is executed on the same kworker CPU as this vhost
1139                  * thread to gain positive L2 cache locality effects.
1140                  */
1141                 INIT_WORK(&cmd->work, vhost_scsi_submission_work);
1142                 queue_work(vhost_scsi_workqueue, &cmd->work);
1143                 ret = 0;
1144 err:
1145                 /*
1146                  * ENXIO:  No more requests, or read error, wait for next kick
1147                  * EINVAL: Invalid response buffer, drop the request
1148                  * EIO:    Respond with bad target
1149                  * EAGAIN: Pending request
1150                  */
1151                 if (ret == -ENXIO)
1152                         break;
1153                 else if (ret == -EIO)
1154                         vhost_scsi_send_bad_target(vs, vq, vc.head, vc.out);
1155         } while (likely(!vhost_exceeds_weight(vq, ++c, 0)));
1156 out:
1157         mutex_unlock(&vq->mutex);
1158 }
1159
1160 static void
1161 vhost_scsi_send_tmf_resp(struct vhost_scsi *vs, struct vhost_virtqueue *vq,
1162                          int in_iovs, int vq_desc, struct iovec *resp_iov,
1163                          int tmf_resp_code)
1164 {
1165         struct virtio_scsi_ctrl_tmf_resp rsp;
1166         struct iov_iter iov_iter;
1167         int ret;
1168
1169         pr_debug("%s\n", __func__);
1170         memset(&rsp, 0, sizeof(rsp));
1171         rsp.response = tmf_resp_code;
1172
1173         iov_iter_init(&iov_iter, READ, resp_iov, in_iovs, sizeof(rsp));
1174
1175         ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter);
1176         if (likely(ret == sizeof(rsp)))
1177                 vhost_add_used_and_signal(&vs->dev, vq, vq_desc, 0);
1178         else
1179                 pr_err("Faulted on virtio_scsi_ctrl_tmf_resp\n");
1180 }
1181
1182 static void vhost_scsi_tmf_resp_work(struct vhost_work *work)
1183 {
1184         struct vhost_scsi_tmf *tmf = container_of(work, struct vhost_scsi_tmf,
1185                                                   vwork);
1186         int resp_code;
1187
1188         if (tmf->scsi_resp == TMR_FUNCTION_COMPLETE)
1189                 resp_code = VIRTIO_SCSI_S_FUNCTION_SUCCEEDED;
1190         else
1191                 resp_code = VIRTIO_SCSI_S_FUNCTION_REJECTED;
1192
1193         vhost_scsi_send_tmf_resp(tmf->vhost, &tmf->svq->vq, tmf->in_iovs,
1194                                  tmf->vq_desc, &tmf->resp_iov, resp_code);
1195         vhost_scsi_release_tmf_res(tmf);
1196 }
1197
1198 static void
1199 vhost_scsi_handle_tmf(struct vhost_scsi *vs, struct vhost_scsi_tpg *tpg,
1200                       struct vhost_virtqueue *vq,
1201                       struct virtio_scsi_ctrl_tmf_req *vtmf,
1202                       struct vhost_scsi_ctx *vc)
1203 {
1204         struct vhost_scsi_virtqueue *svq = container_of(vq,
1205                                         struct vhost_scsi_virtqueue, vq);
1206         struct vhost_scsi_tmf *tmf;
1207
1208         if (vhost32_to_cpu(vq, vtmf->subtype) !=
1209             VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET)
1210                 goto send_reject;
1211
1212         if (!tpg->tpg_nexus || !tpg->tpg_nexus->tvn_se_sess) {
1213                 pr_err("Unable to locate active struct vhost_scsi_nexus for LUN RESET.\n");
1214                 goto send_reject;
1215         }
1216
1217         mutex_lock(&tpg->tv_tpg_mutex);
1218         if (list_empty(&tpg->tmf_queue)) {
1219                 pr_err("Missing reserve TMF. Could not handle LUN RESET.\n");
1220                 mutex_unlock(&tpg->tv_tpg_mutex);
1221                 goto send_reject;
1222         }
1223
1224         tmf = list_first_entry(&tpg->tmf_queue, struct vhost_scsi_tmf,
1225                                queue_entry);
1226         list_del_init(&tmf->queue_entry);
1227         mutex_unlock(&tpg->tv_tpg_mutex);
1228
1229         tmf->tpg = tpg;
1230         tmf->vhost = vs;
1231         tmf->svq = svq;
1232         tmf->resp_iov = vq->iov[vc->out];
1233         tmf->vq_desc = vc->head;
1234         tmf->in_iovs = vc->in;
1235         tmf->inflight = vhost_scsi_get_inflight(vq);
1236
1237         if (target_submit_tmr(&tmf->se_cmd, tpg->tpg_nexus->tvn_se_sess, NULL,
1238                               vhost_buf_to_lun(vtmf->lun), NULL,
1239                               TMR_LUN_RESET, GFP_KERNEL, 0,
1240                               TARGET_SCF_ACK_KREF) < 0) {
1241                 vhost_scsi_release_tmf_res(tmf);
1242                 goto send_reject;
1243         }
1244
1245         return;
1246
1247 send_reject:
1248         vhost_scsi_send_tmf_resp(vs, vq, vc->in, vc->head, &vq->iov[vc->out],
1249                                  VIRTIO_SCSI_S_FUNCTION_REJECTED);
1250 }
1251
1252 static void
1253 vhost_scsi_send_an_resp(struct vhost_scsi *vs,
1254                         struct vhost_virtqueue *vq,
1255                         struct vhost_scsi_ctx *vc)
1256 {
1257         struct virtio_scsi_ctrl_an_resp rsp;
1258         struct iov_iter iov_iter;
1259         int ret;
1260
1261         pr_debug("%s\n", __func__);
1262         memset(&rsp, 0, sizeof(rsp));   /* event_actual = 0 */
1263         rsp.response = VIRTIO_SCSI_S_OK;
1264
1265         iov_iter_init(&iov_iter, READ, &vq->iov[vc->out], vc->in, sizeof(rsp));
1266
1267         ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter);
1268         if (likely(ret == sizeof(rsp)))
1269                 vhost_add_used_and_signal(&vs->dev, vq, vc->head, 0);
1270         else
1271                 pr_err("Faulted on virtio_scsi_ctrl_an_resp\n");
1272 }
1273
1274 static void
1275 vhost_scsi_ctl_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
1276 {
1277         struct vhost_scsi_tpg *tpg;
1278         union {
1279                 __virtio32 type;
1280                 struct virtio_scsi_ctrl_an_req an;
1281                 struct virtio_scsi_ctrl_tmf_req tmf;
1282         } v_req;
1283         struct vhost_scsi_ctx vc;
1284         size_t typ_size;
1285         int ret, c = 0;
1286
1287         mutex_lock(&vq->mutex);
1288         /*
1289          * We can handle the vq only after the endpoint is setup by calling the
1290          * VHOST_SCSI_SET_ENDPOINT ioctl.
1291          */
1292         if (!vhost_vq_get_backend(vq))
1293                 goto out;
1294
1295         memset(&vc, 0, sizeof(vc));
1296
1297         vhost_disable_notify(&vs->dev, vq);
1298
1299         do {
1300                 ret = vhost_scsi_get_desc(vs, vq, &vc);
1301                 if (ret)
1302                         goto err;
1303
1304                 /*
1305                  * Get the request type first in order to setup
1306                  * other parameters dependent on the type.
1307                  */
1308                 vc.req = &v_req.type;
1309                 typ_size = sizeof(v_req.type);
1310
1311                 if (unlikely(!copy_from_iter_full(vc.req, typ_size,
1312                                                   &vc.out_iter))) {
1313                         vq_err(vq, "Faulted on copy_from_iter tmf type\n");
1314                         /*
1315                          * The size of the response buffer depends on the
1316                          * request type and must be validated against it.
1317                          * Since the request type is not known, don't send
1318                          * a response.
1319                          */
1320                         continue;
1321                 }
1322
1323                 switch (vhost32_to_cpu(vq, v_req.type)) {
1324                 case VIRTIO_SCSI_T_TMF:
1325                         vc.req = &v_req.tmf;
1326                         vc.req_size = sizeof(struct virtio_scsi_ctrl_tmf_req);
1327                         vc.rsp_size = sizeof(struct virtio_scsi_ctrl_tmf_resp);
1328                         vc.lunp = &v_req.tmf.lun[0];
1329                         vc.target = &v_req.tmf.lun[1];
1330                         break;
1331                 case VIRTIO_SCSI_T_AN_QUERY:
1332                 case VIRTIO_SCSI_T_AN_SUBSCRIBE:
1333                         vc.req = &v_req.an;
1334                         vc.req_size = sizeof(struct virtio_scsi_ctrl_an_req);
1335                         vc.rsp_size = sizeof(struct virtio_scsi_ctrl_an_resp);
1336                         vc.lunp = &v_req.an.lun[0];
1337                         vc.target = NULL;
1338                         break;
1339                 default:
1340                         vq_err(vq, "Unknown control request %d", v_req.type);
1341                         continue;
1342                 }
1343
1344                 /*
1345                  * Validate the size of request and response buffers.
1346                  * Check for a sane response buffer so we can report
1347                  * early errors back to the guest.
1348                  */
1349                 ret = vhost_scsi_chk_size(vq, &vc);
1350                 if (ret)
1351                         goto err;
1352
1353                 /*
1354                  * Get the rest of the request now that its size is known.
1355                  */
1356                 vc.req += typ_size;
1357                 vc.req_size -= typ_size;
1358
1359                 ret = vhost_scsi_get_req(vq, &vc, &tpg);
1360                 if (ret)
1361                         goto err;
1362
1363                 if (v_req.type == VIRTIO_SCSI_T_TMF)
1364                         vhost_scsi_handle_tmf(vs, tpg, vq, &v_req.tmf, &vc);
1365                 else
1366                         vhost_scsi_send_an_resp(vs, vq, &vc);
1367 err:
1368                 /*
1369                  * ENXIO:  No more requests, or read error, wait for next kick
1370                  * EINVAL: Invalid response buffer, drop the request
1371                  * EIO:    Respond with bad target
1372                  * EAGAIN: Pending request
1373                  */
1374                 if (ret == -ENXIO)
1375                         break;
1376                 else if (ret == -EIO)
1377                         vhost_scsi_send_bad_target(vs, vq, vc.head, vc.out);
1378         } while (likely(!vhost_exceeds_weight(vq, ++c, 0)));
1379 out:
1380         mutex_unlock(&vq->mutex);
1381 }
1382
1383 static void vhost_scsi_ctl_handle_kick(struct vhost_work *work)
1384 {
1385         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1386                                                 poll.work);
1387         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1388
1389         pr_debug("%s: The handling func for control queue.\n", __func__);
1390         vhost_scsi_ctl_handle_vq(vs, vq);
1391 }
1392
1393 static void
1394 vhost_scsi_send_evt(struct vhost_scsi *vs,
1395                    struct vhost_scsi_tpg *tpg,
1396                    struct se_lun *lun,
1397                    u32 event,
1398                    u32 reason)
1399 {
1400         struct vhost_scsi_evt *evt;
1401
1402         evt = vhost_scsi_allocate_evt(vs, event, reason);
1403         if (!evt)
1404                 return;
1405
1406         if (tpg && lun) {
1407                 /* TODO: share lun setup code with virtio-scsi.ko */
1408                 /*
1409                  * Note: evt->event is zeroed when we allocate it and
1410                  * lun[4-7] need to be zero according to virtio-scsi spec.
1411                  */
1412                 evt->event.lun[0] = 0x01;
1413                 evt->event.lun[1] = tpg->tport_tpgt;
1414                 if (lun->unpacked_lun >= 256)
1415                         evt->event.lun[2] = lun->unpacked_lun >> 8 | 0x40 ;
1416                 evt->event.lun[3] = lun->unpacked_lun & 0xFF;
1417         }
1418
1419         llist_add(&evt->list, &vs->vs_event_list);
1420         vhost_work_queue(&vs->dev, &vs->vs_event_work);
1421 }
1422
1423 static void vhost_scsi_evt_handle_kick(struct vhost_work *work)
1424 {
1425         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1426                                                 poll.work);
1427         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1428
1429         mutex_lock(&vq->mutex);
1430         if (!vhost_vq_get_backend(vq))
1431                 goto out;
1432
1433         if (vs->vs_events_missed)
1434                 vhost_scsi_send_evt(vs, NULL, NULL, VIRTIO_SCSI_T_NO_EVENT, 0);
1435 out:
1436         mutex_unlock(&vq->mutex);
1437 }
1438
1439 static void vhost_scsi_handle_kick(struct vhost_work *work)
1440 {
1441         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1442                                                 poll.work);
1443         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1444
1445         vhost_scsi_handle_vq(vs, vq);
1446 }
1447
1448 static void vhost_scsi_flush_vq(struct vhost_scsi *vs, int index)
1449 {
1450         vhost_poll_flush(&vs->vqs[index].vq.poll);
1451 }
1452
1453 /* Callers must hold dev mutex */
1454 static void vhost_scsi_flush(struct vhost_scsi *vs)
1455 {
1456         struct vhost_scsi_inflight *old_inflight[VHOST_SCSI_MAX_VQ];
1457         int i;
1458
1459         /* Init new inflight and remember the old inflight */
1460         vhost_scsi_init_inflight(vs, old_inflight);
1461
1462         /*
1463          * The inflight->kref was initialized to 1. We decrement it here to
1464          * indicate the start of the flush operation so that it will reach 0
1465          * when all the reqs are finished.
1466          */
1467         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1468                 kref_put(&old_inflight[i]->kref, vhost_scsi_done_inflight);
1469
1470         /* Flush both the vhost poll and vhost work */
1471         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1472                 vhost_scsi_flush_vq(vs, i);
1473         vhost_work_flush(&vs->dev, &vs->vs_completion_work);
1474         vhost_work_flush(&vs->dev, &vs->vs_event_work);
1475
1476         /* Wait for all reqs issued before the flush to be finished */
1477         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1478                 wait_for_completion(&old_inflight[i]->comp);
1479 }
1480
1481 static void vhost_scsi_destroy_vq_cmds(struct vhost_virtqueue *vq)
1482 {
1483         struct vhost_scsi_virtqueue *svq = container_of(vq,
1484                                         struct vhost_scsi_virtqueue, vq);
1485         struct vhost_scsi_cmd *tv_cmd;
1486         unsigned int i;
1487
1488         if (!svq->scsi_cmds)
1489                 return;
1490
1491         for (i = 0; i < svq->max_cmds; i++) {
1492                 tv_cmd = &svq->scsi_cmds[i];
1493
1494                 kfree(tv_cmd->tvc_sgl);
1495                 kfree(tv_cmd->tvc_prot_sgl);
1496                 kfree(tv_cmd->tvc_upages);
1497         }
1498
1499         sbitmap_free(&svq->scsi_tags);
1500         kfree(svq->scsi_cmds);
1501         svq->scsi_cmds = NULL;
1502 }
1503
1504 static int vhost_scsi_setup_vq_cmds(struct vhost_virtqueue *vq, int max_cmds)
1505 {
1506         struct vhost_scsi_virtqueue *svq = container_of(vq,
1507                                         struct vhost_scsi_virtqueue, vq);
1508         struct vhost_scsi_cmd *tv_cmd;
1509         unsigned int i;
1510
1511         if (svq->scsi_cmds)
1512                 return 0;
1513
1514         if (sbitmap_init_node(&svq->scsi_tags, max_cmds, -1, GFP_KERNEL,
1515                               NUMA_NO_NODE))
1516                 return -ENOMEM;
1517         svq->max_cmds = max_cmds;
1518
1519         svq->scsi_cmds = kcalloc(max_cmds, sizeof(*tv_cmd), GFP_KERNEL);
1520         if (!svq->scsi_cmds) {
1521                 sbitmap_free(&svq->scsi_tags);
1522                 return -ENOMEM;
1523         }
1524
1525         for (i = 0; i < max_cmds; i++) {
1526                 tv_cmd = &svq->scsi_cmds[i];
1527
1528                 tv_cmd->tvc_sgl = kcalloc(VHOST_SCSI_PREALLOC_SGLS,
1529                                           sizeof(struct scatterlist),
1530                                           GFP_KERNEL);
1531                 if (!tv_cmd->tvc_sgl) {
1532                         pr_err("Unable to allocate tv_cmd->tvc_sgl\n");
1533                         goto out;
1534                 }
1535
1536                 tv_cmd->tvc_upages = kcalloc(VHOST_SCSI_PREALLOC_UPAGES,
1537                                              sizeof(struct page *),
1538                                              GFP_KERNEL);
1539                 if (!tv_cmd->tvc_upages) {
1540                         pr_err("Unable to allocate tv_cmd->tvc_upages\n");
1541                         goto out;
1542                 }
1543
1544                 tv_cmd->tvc_prot_sgl = kcalloc(VHOST_SCSI_PREALLOC_PROT_SGLS,
1545                                                sizeof(struct scatterlist),
1546                                                GFP_KERNEL);
1547                 if (!tv_cmd->tvc_prot_sgl) {
1548                         pr_err("Unable to allocate tv_cmd->tvc_prot_sgl\n");
1549                         goto out;
1550                 }
1551         }
1552         return 0;
1553 out:
1554         vhost_scsi_destroy_vq_cmds(vq);
1555         return -ENOMEM;
1556 }
1557
1558 /*
1559  * Called from vhost_scsi_ioctl() context to walk the list of available
1560  * vhost_scsi_tpg with an active struct vhost_scsi_nexus
1561  *
1562  *  The lock nesting rule is:
1563  *    vhost_scsi_mutex -> vs->dev.mutex -> tpg->tv_tpg_mutex -> vq->mutex
1564  */
1565 static int
1566 vhost_scsi_set_endpoint(struct vhost_scsi *vs,
1567                         struct vhost_scsi_target *t)
1568 {
1569         struct se_portal_group *se_tpg;
1570         struct vhost_scsi_tport *tv_tport;
1571         struct vhost_scsi_tpg *tpg;
1572         struct vhost_scsi_tpg **vs_tpg;
1573         struct vhost_virtqueue *vq;
1574         int index, ret, i, len;
1575         bool match = false;
1576
1577         mutex_lock(&vhost_scsi_mutex);
1578         mutex_lock(&vs->dev.mutex);
1579
1580         /* Verify that ring has been setup correctly. */
1581         for (index = 0; index < vs->dev.nvqs; ++index) {
1582                 /* Verify that ring has been setup correctly. */
1583                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1584                         ret = -EFAULT;
1585                         goto out;
1586                 }
1587         }
1588
1589         len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET;
1590         vs_tpg = kzalloc(len, GFP_KERNEL);
1591         if (!vs_tpg) {
1592                 ret = -ENOMEM;
1593                 goto out;
1594         }
1595         if (vs->vs_tpg)
1596                 memcpy(vs_tpg, vs->vs_tpg, len);
1597
1598         list_for_each_entry(tpg, &vhost_scsi_list, tv_tpg_list) {
1599                 mutex_lock(&tpg->tv_tpg_mutex);
1600                 if (!tpg->tpg_nexus) {
1601                         mutex_unlock(&tpg->tv_tpg_mutex);
1602                         continue;
1603                 }
1604                 if (tpg->tv_tpg_vhost_count != 0) {
1605                         mutex_unlock(&tpg->tv_tpg_mutex);
1606                         continue;
1607                 }
1608                 tv_tport = tpg->tport;
1609
1610                 if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1611                         if (vs->vs_tpg && vs->vs_tpg[tpg->tport_tpgt]) {
1612                                 mutex_unlock(&tpg->tv_tpg_mutex);
1613                                 ret = -EEXIST;
1614                                 goto undepend;
1615                         }
1616                         /*
1617                          * In order to ensure individual vhost-scsi configfs
1618                          * groups cannot be removed while in use by vhost ioctl,
1619                          * go ahead and take an explicit se_tpg->tpg_group.cg_item
1620                          * dependency now.
1621                          */
1622                         se_tpg = &tpg->se_tpg;
1623                         ret = target_depend_item(&se_tpg->tpg_group.cg_item);
1624                         if (ret) {
1625                                 pr_warn("target_depend_item() failed: %d\n", ret);
1626                                 mutex_unlock(&tpg->tv_tpg_mutex);
1627                                 goto undepend;
1628                         }
1629                         tpg->tv_tpg_vhost_count++;
1630                         tpg->vhost_scsi = vs;
1631                         vs_tpg[tpg->tport_tpgt] = tpg;
1632                         match = true;
1633                 }
1634                 mutex_unlock(&tpg->tv_tpg_mutex);
1635         }
1636
1637         if (match) {
1638                 memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
1639                        sizeof(vs->vs_vhost_wwpn));
1640
1641                 for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++) {
1642                         vq = &vs->vqs[i].vq;
1643                         if (!vhost_vq_is_setup(vq))
1644                                 continue;
1645
1646                         ret = vhost_scsi_setup_vq_cmds(vq, vq->num);
1647                         if (ret)
1648                                 goto destroy_vq_cmds;
1649                 }
1650
1651                 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1652                         vq = &vs->vqs[i].vq;
1653                         mutex_lock(&vq->mutex);
1654                         vhost_vq_set_backend(vq, vs_tpg);
1655                         vhost_vq_init_access(vq);
1656                         mutex_unlock(&vq->mutex);
1657                 }
1658                 ret = 0;
1659         } else {
1660                 ret = -EEXIST;
1661         }
1662
1663         /*
1664          * Act as synchronize_rcu to make sure access to
1665          * old vs->vs_tpg is finished.
1666          */
1667         vhost_scsi_flush(vs);
1668         kfree(vs->vs_tpg);
1669         vs->vs_tpg = vs_tpg;
1670         goto out;
1671
1672 destroy_vq_cmds:
1673         for (i--; i >= VHOST_SCSI_VQ_IO; i--) {
1674                 if (!vhost_vq_get_backend(&vs->vqs[i].vq))
1675                         vhost_scsi_destroy_vq_cmds(&vs->vqs[i].vq);
1676         }
1677 undepend:
1678         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1679                 tpg = vs_tpg[i];
1680                 if (tpg) {
1681                         tpg->tv_tpg_vhost_count--;
1682                         target_undepend_item(&tpg->se_tpg.tpg_group.cg_item);
1683                 }
1684         }
1685         kfree(vs_tpg);
1686 out:
1687         mutex_unlock(&vs->dev.mutex);
1688         mutex_unlock(&vhost_scsi_mutex);
1689         return ret;
1690 }
1691
1692 static int
1693 vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
1694                           struct vhost_scsi_target *t)
1695 {
1696         struct se_portal_group *se_tpg;
1697         struct vhost_scsi_tport *tv_tport;
1698         struct vhost_scsi_tpg *tpg;
1699         struct vhost_virtqueue *vq;
1700         bool match = false;
1701         int index, ret, i;
1702         u8 target;
1703
1704         mutex_lock(&vhost_scsi_mutex);
1705         mutex_lock(&vs->dev.mutex);
1706         /* Verify that ring has been setup correctly. */
1707         for (index = 0; index < vs->dev.nvqs; ++index) {
1708                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1709                         ret = -EFAULT;
1710                         goto err_dev;
1711                 }
1712         }
1713
1714         if (!vs->vs_tpg) {
1715                 ret = 0;
1716                 goto err_dev;
1717         }
1718
1719         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1720                 target = i;
1721                 tpg = vs->vs_tpg[target];
1722                 if (!tpg)
1723                         continue;
1724
1725                 mutex_lock(&tpg->tv_tpg_mutex);
1726                 tv_tport = tpg->tport;
1727                 if (!tv_tport) {
1728                         ret = -ENODEV;
1729                         goto err_tpg;
1730                 }
1731
1732                 if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1733                         pr_warn("tv_tport->tport_name: %s, tpg->tport_tpgt: %hu"
1734                                 " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
1735                                 tv_tport->tport_name, tpg->tport_tpgt,
1736                                 t->vhost_wwpn, t->vhost_tpgt);
1737                         ret = -EINVAL;
1738                         goto err_tpg;
1739                 }
1740                 tpg->tv_tpg_vhost_count--;
1741                 tpg->vhost_scsi = NULL;
1742                 vs->vs_tpg[target] = NULL;
1743                 match = true;
1744                 mutex_unlock(&tpg->tv_tpg_mutex);
1745                 /*
1746                  * Release se_tpg->tpg_group.cg_item configfs dependency now
1747                  * to allow vhost-scsi WWPN se_tpg->tpg_group shutdown to occur.
1748                  */
1749                 se_tpg = &tpg->se_tpg;
1750                 target_undepend_item(&se_tpg->tpg_group.cg_item);
1751         }
1752         if (match) {
1753                 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1754                         vq = &vs->vqs[i].vq;
1755                         mutex_lock(&vq->mutex);
1756                         vhost_vq_set_backend(vq, NULL);
1757                         mutex_unlock(&vq->mutex);
1758                         /*
1759                          * Make sure cmds are not running before tearing them
1760                          * down.
1761                          */
1762                         vhost_scsi_flush(vs);
1763                         vhost_scsi_destroy_vq_cmds(vq);
1764                 }
1765         }
1766         /*
1767          * Act as synchronize_rcu to make sure access to
1768          * old vs->vs_tpg is finished.
1769          */
1770         vhost_scsi_flush(vs);
1771         kfree(vs->vs_tpg);
1772         vs->vs_tpg = NULL;
1773         WARN_ON(vs->vs_events_nr);
1774         mutex_unlock(&vs->dev.mutex);
1775         mutex_unlock(&vhost_scsi_mutex);
1776         return 0;
1777
1778 err_tpg:
1779         mutex_unlock(&tpg->tv_tpg_mutex);
1780 err_dev:
1781         mutex_unlock(&vs->dev.mutex);
1782         mutex_unlock(&vhost_scsi_mutex);
1783         return ret;
1784 }
1785
1786 static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features)
1787 {
1788         struct vhost_virtqueue *vq;
1789         int i;
1790
1791         if (features & ~VHOST_SCSI_FEATURES)
1792                 return -EOPNOTSUPP;
1793
1794         mutex_lock(&vs->dev.mutex);
1795         if ((features & (1 << VHOST_F_LOG_ALL)) &&
1796             !vhost_log_access_ok(&vs->dev)) {
1797                 mutex_unlock(&vs->dev.mutex);
1798                 return -EFAULT;
1799         }
1800
1801         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1802                 vq = &vs->vqs[i].vq;
1803                 mutex_lock(&vq->mutex);
1804                 vq->acked_features = features;
1805                 mutex_unlock(&vq->mutex);
1806         }
1807         mutex_unlock(&vs->dev.mutex);
1808         return 0;
1809 }
1810
1811 static int vhost_scsi_open(struct inode *inode, struct file *f)
1812 {
1813         struct vhost_scsi *vs;
1814         struct vhost_virtqueue **vqs;
1815         int r = -ENOMEM, i;
1816
1817         vs = kvzalloc(sizeof(*vs), GFP_KERNEL);
1818         if (!vs)
1819                 goto err_vs;
1820
1821         vqs = kmalloc_array(VHOST_SCSI_MAX_VQ, sizeof(*vqs), GFP_KERNEL);
1822         if (!vqs)
1823                 goto err_vqs;
1824
1825         vhost_work_init(&vs->vs_completion_work, vhost_scsi_complete_cmd_work);
1826         vhost_work_init(&vs->vs_event_work, vhost_scsi_evt_work);
1827
1828         vs->vs_events_nr = 0;
1829         vs->vs_events_missed = false;
1830
1831         vqs[VHOST_SCSI_VQ_CTL] = &vs->vqs[VHOST_SCSI_VQ_CTL].vq;
1832         vqs[VHOST_SCSI_VQ_EVT] = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1833         vs->vqs[VHOST_SCSI_VQ_CTL].vq.handle_kick = vhost_scsi_ctl_handle_kick;
1834         vs->vqs[VHOST_SCSI_VQ_EVT].vq.handle_kick = vhost_scsi_evt_handle_kick;
1835         for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++) {
1836                 vqs[i] = &vs->vqs[i].vq;
1837                 vs->vqs[i].vq.handle_kick = vhost_scsi_handle_kick;
1838         }
1839         vhost_dev_init(&vs->dev, vqs, VHOST_SCSI_MAX_VQ, UIO_MAXIOV,
1840                        VHOST_SCSI_WEIGHT, 0, true, NULL);
1841
1842         vhost_scsi_init_inflight(vs, NULL);
1843
1844         f->private_data = vs;
1845         return 0;
1846
1847 err_vqs:
1848         kvfree(vs);
1849 err_vs:
1850         return r;
1851 }
1852
1853 static int vhost_scsi_release(struct inode *inode, struct file *f)
1854 {
1855         struct vhost_scsi *vs = f->private_data;
1856         struct vhost_scsi_target t;
1857
1858         mutex_lock(&vs->dev.mutex);
1859         memcpy(t.vhost_wwpn, vs->vs_vhost_wwpn, sizeof(t.vhost_wwpn));
1860         mutex_unlock(&vs->dev.mutex);
1861         vhost_scsi_clear_endpoint(vs, &t);
1862         vhost_dev_stop(&vs->dev);
1863         vhost_dev_cleanup(&vs->dev);
1864         /* Jobs can re-queue themselves in evt kick handler. Do extra flush. */
1865         vhost_scsi_flush(vs);
1866         kfree(vs->dev.vqs);
1867         kvfree(vs);
1868         return 0;
1869 }
1870
1871 static long
1872 vhost_scsi_ioctl(struct file *f,
1873                  unsigned int ioctl,
1874                  unsigned long arg)
1875 {
1876         struct vhost_scsi *vs = f->private_data;
1877         struct vhost_scsi_target backend;
1878         void __user *argp = (void __user *)arg;
1879         u64 __user *featurep = argp;
1880         u32 __user *eventsp = argp;
1881         u32 events_missed;
1882         u64 features;
1883         int r, abi_version = VHOST_SCSI_ABI_VERSION;
1884         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1885
1886         switch (ioctl) {
1887         case VHOST_SCSI_SET_ENDPOINT:
1888                 if (copy_from_user(&backend, argp, sizeof backend))
1889                         return -EFAULT;
1890                 if (backend.reserved != 0)
1891                         return -EOPNOTSUPP;
1892
1893                 return vhost_scsi_set_endpoint(vs, &backend);
1894         case VHOST_SCSI_CLEAR_ENDPOINT:
1895                 if (copy_from_user(&backend, argp, sizeof backend))
1896                         return -EFAULT;
1897                 if (backend.reserved != 0)
1898                         return -EOPNOTSUPP;
1899
1900                 return vhost_scsi_clear_endpoint(vs, &backend);
1901         case VHOST_SCSI_GET_ABI_VERSION:
1902                 if (copy_to_user(argp, &abi_version, sizeof abi_version))
1903                         return -EFAULT;
1904                 return 0;
1905         case VHOST_SCSI_SET_EVENTS_MISSED:
1906                 if (get_user(events_missed, eventsp))
1907                         return -EFAULT;
1908                 mutex_lock(&vq->mutex);
1909                 vs->vs_events_missed = events_missed;
1910                 mutex_unlock(&vq->mutex);
1911                 return 0;
1912         case VHOST_SCSI_GET_EVENTS_MISSED:
1913                 mutex_lock(&vq->mutex);
1914                 events_missed = vs->vs_events_missed;
1915                 mutex_unlock(&vq->mutex);
1916                 if (put_user(events_missed, eventsp))
1917                         return -EFAULT;
1918                 return 0;
1919         case VHOST_GET_FEATURES:
1920                 features = VHOST_SCSI_FEATURES;
1921                 if (copy_to_user(featurep, &features, sizeof features))
1922                         return -EFAULT;
1923                 return 0;
1924         case VHOST_SET_FEATURES:
1925                 if (copy_from_user(&features, featurep, sizeof features))
1926                         return -EFAULT;
1927                 return vhost_scsi_set_features(vs, features);
1928         default:
1929                 mutex_lock(&vs->dev.mutex);
1930                 r = vhost_dev_ioctl(&vs->dev, ioctl, argp);
1931                 /* TODO: flush backend after dev ioctl. */
1932                 if (r == -ENOIOCTLCMD)
1933                         r = vhost_vring_ioctl(&vs->dev, ioctl, argp);
1934                 mutex_unlock(&vs->dev.mutex);
1935                 return r;
1936         }
1937 }
1938
1939 static const struct file_operations vhost_scsi_fops = {
1940         .owner          = THIS_MODULE,
1941         .release        = vhost_scsi_release,
1942         .unlocked_ioctl = vhost_scsi_ioctl,
1943         .compat_ioctl   = compat_ptr_ioctl,
1944         .open           = vhost_scsi_open,
1945         .llseek         = noop_llseek,
1946 };
1947
1948 static struct miscdevice vhost_scsi_misc = {
1949         MISC_DYNAMIC_MINOR,
1950         "vhost-scsi",
1951         &vhost_scsi_fops,
1952 };
1953
1954 static int __init vhost_scsi_register(void)
1955 {
1956         return misc_register(&vhost_scsi_misc);
1957 }
1958
1959 static void vhost_scsi_deregister(void)
1960 {
1961         misc_deregister(&vhost_scsi_misc);
1962 }
1963
1964 static char *vhost_scsi_dump_proto_id(struct vhost_scsi_tport *tport)
1965 {
1966         switch (tport->tport_proto_id) {
1967         case SCSI_PROTOCOL_SAS:
1968                 return "SAS";
1969         case SCSI_PROTOCOL_FCP:
1970                 return "FCP";
1971         case SCSI_PROTOCOL_ISCSI:
1972                 return "iSCSI";
1973         default:
1974                 break;
1975         }
1976
1977         return "Unknown";
1978 }
1979
1980 static void
1981 vhost_scsi_do_plug(struct vhost_scsi_tpg *tpg,
1982                   struct se_lun *lun, bool plug)
1983 {
1984
1985         struct vhost_scsi *vs = tpg->vhost_scsi;
1986         struct vhost_virtqueue *vq;
1987         u32 reason;
1988
1989         if (!vs)
1990                 return;
1991
1992         mutex_lock(&vs->dev.mutex);
1993
1994         if (plug)
1995                 reason = VIRTIO_SCSI_EVT_RESET_RESCAN;
1996         else
1997                 reason = VIRTIO_SCSI_EVT_RESET_REMOVED;
1998
1999         vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
2000         mutex_lock(&vq->mutex);
2001         if (vhost_has_feature(vq, VIRTIO_SCSI_F_HOTPLUG))
2002                 vhost_scsi_send_evt(vs, tpg, lun,
2003                                    VIRTIO_SCSI_T_TRANSPORT_RESET, reason);
2004         mutex_unlock(&vq->mutex);
2005         mutex_unlock(&vs->dev.mutex);
2006 }
2007
2008 static void vhost_scsi_hotplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
2009 {
2010         vhost_scsi_do_plug(tpg, lun, true);
2011 }
2012
2013 static void vhost_scsi_hotunplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
2014 {
2015         vhost_scsi_do_plug(tpg, lun, false);
2016 }
2017
2018 static int vhost_scsi_port_link(struct se_portal_group *se_tpg,
2019                                struct se_lun *lun)
2020 {
2021         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2022                                 struct vhost_scsi_tpg, se_tpg);
2023         struct vhost_scsi_tmf *tmf;
2024
2025         tmf = kzalloc(sizeof(*tmf), GFP_KERNEL);
2026         if (!tmf)
2027                 return -ENOMEM;
2028         INIT_LIST_HEAD(&tmf->queue_entry);
2029         vhost_work_init(&tmf->vwork, vhost_scsi_tmf_resp_work);
2030
2031         mutex_lock(&vhost_scsi_mutex);
2032
2033         mutex_lock(&tpg->tv_tpg_mutex);
2034         tpg->tv_tpg_port_count++;
2035         list_add_tail(&tmf->queue_entry, &tpg->tmf_queue);
2036         mutex_unlock(&tpg->tv_tpg_mutex);
2037
2038         vhost_scsi_hotplug(tpg, lun);
2039
2040         mutex_unlock(&vhost_scsi_mutex);
2041
2042         return 0;
2043 }
2044
2045 static void vhost_scsi_port_unlink(struct se_portal_group *se_tpg,
2046                                   struct se_lun *lun)
2047 {
2048         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2049                                 struct vhost_scsi_tpg, se_tpg);
2050         struct vhost_scsi_tmf *tmf;
2051
2052         mutex_lock(&vhost_scsi_mutex);
2053
2054         mutex_lock(&tpg->tv_tpg_mutex);
2055         tpg->tv_tpg_port_count--;
2056         tmf = list_first_entry(&tpg->tmf_queue, struct vhost_scsi_tmf,
2057                                queue_entry);
2058         list_del(&tmf->queue_entry);
2059         kfree(tmf);
2060         mutex_unlock(&tpg->tv_tpg_mutex);
2061
2062         vhost_scsi_hotunplug(tpg, lun);
2063
2064         mutex_unlock(&vhost_scsi_mutex);
2065 }
2066
2067 static ssize_t vhost_scsi_tpg_attrib_fabric_prot_type_store(
2068                 struct config_item *item, const char *page, size_t count)
2069 {
2070         struct se_portal_group *se_tpg = attrib_to_tpg(item);
2071         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2072                                 struct vhost_scsi_tpg, se_tpg);
2073         unsigned long val;
2074         int ret = kstrtoul(page, 0, &val);
2075
2076         if (ret) {
2077                 pr_err("kstrtoul() returned %d for fabric_prot_type\n", ret);
2078                 return ret;
2079         }
2080         if (val != 0 && val != 1 && val != 3) {
2081                 pr_err("Invalid vhost_scsi fabric_prot_type: %lu\n", val);
2082                 return -EINVAL;
2083         }
2084         tpg->tv_fabric_prot_type = val;
2085
2086         return count;
2087 }
2088
2089 static ssize_t vhost_scsi_tpg_attrib_fabric_prot_type_show(
2090                 struct config_item *item, char *page)
2091 {
2092         struct se_portal_group *se_tpg = attrib_to_tpg(item);
2093         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2094                                 struct vhost_scsi_tpg, se_tpg);
2095
2096         return sprintf(page, "%d\n", tpg->tv_fabric_prot_type);
2097 }
2098
2099 CONFIGFS_ATTR(vhost_scsi_tpg_attrib_, fabric_prot_type);
2100
2101 static struct configfs_attribute *vhost_scsi_tpg_attrib_attrs[] = {
2102         &vhost_scsi_tpg_attrib_attr_fabric_prot_type,
2103         NULL,
2104 };
2105
2106 static int vhost_scsi_make_nexus(struct vhost_scsi_tpg *tpg,
2107                                 const char *name)
2108 {
2109         struct vhost_scsi_nexus *tv_nexus;
2110
2111         mutex_lock(&tpg->tv_tpg_mutex);
2112         if (tpg->tpg_nexus) {
2113                 mutex_unlock(&tpg->tv_tpg_mutex);
2114                 pr_debug("tpg->tpg_nexus already exists\n");
2115                 return -EEXIST;
2116         }
2117
2118         tv_nexus = kzalloc(sizeof(*tv_nexus), GFP_KERNEL);
2119         if (!tv_nexus) {
2120                 mutex_unlock(&tpg->tv_tpg_mutex);
2121                 pr_err("Unable to allocate struct vhost_scsi_nexus\n");
2122                 return -ENOMEM;
2123         }
2124         /*
2125          * Since we are running in 'demo mode' this call with generate a
2126          * struct se_node_acl for the vhost_scsi struct se_portal_group with
2127          * the SCSI Initiator port name of the passed configfs group 'name'.
2128          */
2129         tv_nexus->tvn_se_sess = target_setup_session(&tpg->se_tpg, 0, 0,
2130                                         TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS,
2131                                         (unsigned char *)name, tv_nexus, NULL);
2132         if (IS_ERR(tv_nexus->tvn_se_sess)) {
2133                 mutex_unlock(&tpg->tv_tpg_mutex);
2134                 kfree(tv_nexus);
2135                 return -ENOMEM;
2136         }
2137         tpg->tpg_nexus = tv_nexus;
2138
2139         mutex_unlock(&tpg->tv_tpg_mutex);
2140         return 0;
2141 }
2142
2143 static int vhost_scsi_drop_nexus(struct vhost_scsi_tpg *tpg)
2144 {
2145         struct se_session *se_sess;
2146         struct vhost_scsi_nexus *tv_nexus;
2147
2148         mutex_lock(&tpg->tv_tpg_mutex);
2149         tv_nexus = tpg->tpg_nexus;
2150         if (!tv_nexus) {
2151                 mutex_unlock(&tpg->tv_tpg_mutex);
2152                 return -ENODEV;
2153         }
2154
2155         se_sess = tv_nexus->tvn_se_sess;
2156         if (!se_sess) {
2157                 mutex_unlock(&tpg->tv_tpg_mutex);
2158                 return -ENODEV;
2159         }
2160
2161         if (tpg->tv_tpg_port_count != 0) {
2162                 mutex_unlock(&tpg->tv_tpg_mutex);
2163                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
2164                         " active TPG port count: %d\n",
2165                         tpg->tv_tpg_port_count);
2166                 return -EBUSY;
2167         }
2168
2169         if (tpg->tv_tpg_vhost_count != 0) {
2170                 mutex_unlock(&tpg->tv_tpg_mutex);
2171                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
2172                         " active TPG vhost count: %d\n",
2173                         tpg->tv_tpg_vhost_count);
2174                 return -EBUSY;
2175         }
2176
2177         pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated"
2178                 " %s Initiator Port: %s\n", vhost_scsi_dump_proto_id(tpg->tport),
2179                 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
2180
2181         /*
2182          * Release the SCSI I_T Nexus to the emulated vhost Target Port
2183          */
2184         target_remove_session(se_sess);
2185         tpg->tpg_nexus = NULL;
2186         mutex_unlock(&tpg->tv_tpg_mutex);
2187
2188         kfree(tv_nexus);
2189         return 0;
2190 }
2191
2192 static ssize_t vhost_scsi_tpg_nexus_show(struct config_item *item, char *page)
2193 {
2194         struct se_portal_group *se_tpg = to_tpg(item);
2195         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2196                                 struct vhost_scsi_tpg, se_tpg);
2197         struct vhost_scsi_nexus *tv_nexus;
2198         ssize_t ret;
2199
2200         mutex_lock(&tpg->tv_tpg_mutex);
2201         tv_nexus = tpg->tpg_nexus;
2202         if (!tv_nexus) {
2203                 mutex_unlock(&tpg->tv_tpg_mutex);
2204                 return -ENODEV;
2205         }
2206         ret = snprintf(page, PAGE_SIZE, "%s\n",
2207                         tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
2208         mutex_unlock(&tpg->tv_tpg_mutex);
2209
2210         return ret;
2211 }
2212
2213 static ssize_t vhost_scsi_tpg_nexus_store(struct config_item *item,
2214                 const char *page, size_t count)
2215 {
2216         struct se_portal_group *se_tpg = to_tpg(item);
2217         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2218                                 struct vhost_scsi_tpg, se_tpg);
2219         struct vhost_scsi_tport *tport_wwn = tpg->tport;
2220         unsigned char i_port[VHOST_SCSI_NAMELEN], *ptr, *port_ptr;
2221         int ret;
2222         /*
2223          * Shutdown the active I_T nexus if 'NULL' is passed..
2224          */
2225         if (!strncmp(page, "NULL", 4)) {
2226                 ret = vhost_scsi_drop_nexus(tpg);
2227                 return (!ret) ? count : ret;
2228         }
2229         /*
2230          * Otherwise make sure the passed virtual Initiator port WWN matches
2231          * the fabric protocol_id set in vhost_scsi_make_tport(), and call
2232          * vhost_scsi_make_nexus().
2233          */
2234         if (strlen(page) >= VHOST_SCSI_NAMELEN) {
2235                 pr_err("Emulated NAA Sas Address: %s, exceeds"
2236                                 " max: %d\n", page, VHOST_SCSI_NAMELEN);
2237                 return -EINVAL;
2238         }
2239         snprintf(&i_port[0], VHOST_SCSI_NAMELEN, "%s", page);
2240
2241         ptr = strstr(i_port, "naa.");
2242         if (ptr) {
2243                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
2244                         pr_err("Passed SAS Initiator Port %s does not"
2245                                 " match target port protoid: %s\n", i_port,
2246                                 vhost_scsi_dump_proto_id(tport_wwn));
2247                         return -EINVAL;
2248                 }
2249                 port_ptr = &i_port[0];
2250                 goto check_newline;
2251         }
2252         ptr = strstr(i_port, "fc.");
2253         if (ptr) {
2254                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
2255                         pr_err("Passed FCP Initiator Port %s does not"
2256                                 " match target port protoid: %s\n", i_port,
2257                                 vhost_scsi_dump_proto_id(tport_wwn));
2258                         return -EINVAL;
2259                 }
2260                 port_ptr = &i_port[3]; /* Skip over "fc." */
2261                 goto check_newline;
2262         }
2263         ptr = strstr(i_port, "iqn.");
2264         if (ptr) {
2265                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
2266                         pr_err("Passed iSCSI Initiator Port %s does not"
2267                                 " match target port protoid: %s\n", i_port,
2268                                 vhost_scsi_dump_proto_id(tport_wwn));
2269                         return -EINVAL;
2270                 }
2271                 port_ptr = &i_port[0];
2272                 goto check_newline;
2273         }
2274         pr_err("Unable to locate prefix for emulated Initiator Port:"
2275                         " %s\n", i_port);
2276         return -EINVAL;
2277         /*
2278          * Clear any trailing newline for the NAA WWN
2279          */
2280 check_newline:
2281         if (i_port[strlen(i_port)-1] == '\n')
2282                 i_port[strlen(i_port)-1] = '\0';
2283
2284         ret = vhost_scsi_make_nexus(tpg, port_ptr);
2285         if (ret < 0)
2286                 return ret;
2287
2288         return count;
2289 }
2290
2291 CONFIGFS_ATTR(vhost_scsi_tpg_, nexus);
2292
2293 static struct configfs_attribute *vhost_scsi_tpg_attrs[] = {
2294         &vhost_scsi_tpg_attr_nexus,
2295         NULL,
2296 };
2297
2298 static struct se_portal_group *
2299 vhost_scsi_make_tpg(struct se_wwn *wwn, const char *name)
2300 {
2301         struct vhost_scsi_tport *tport = container_of(wwn,
2302                         struct vhost_scsi_tport, tport_wwn);
2303
2304         struct vhost_scsi_tpg *tpg;
2305         u16 tpgt;
2306         int ret;
2307
2308         if (strstr(name, "tpgt_") != name)
2309                 return ERR_PTR(-EINVAL);
2310         if (kstrtou16(name + 5, 10, &tpgt) || tpgt >= VHOST_SCSI_MAX_TARGET)
2311                 return ERR_PTR(-EINVAL);
2312
2313         tpg = kzalloc(sizeof(*tpg), GFP_KERNEL);
2314         if (!tpg) {
2315                 pr_err("Unable to allocate struct vhost_scsi_tpg");
2316                 return ERR_PTR(-ENOMEM);
2317         }
2318         mutex_init(&tpg->tv_tpg_mutex);
2319         INIT_LIST_HEAD(&tpg->tv_tpg_list);
2320         INIT_LIST_HEAD(&tpg->tmf_queue);
2321         tpg->tport = tport;
2322         tpg->tport_tpgt = tpgt;
2323
2324         ret = core_tpg_register(wwn, &tpg->se_tpg, tport->tport_proto_id);
2325         if (ret < 0) {
2326                 kfree(tpg);
2327                 return NULL;
2328         }
2329         mutex_lock(&vhost_scsi_mutex);
2330         list_add_tail(&tpg->tv_tpg_list, &vhost_scsi_list);
2331         mutex_unlock(&vhost_scsi_mutex);
2332
2333         return &tpg->se_tpg;
2334 }
2335
2336 static void vhost_scsi_drop_tpg(struct se_portal_group *se_tpg)
2337 {
2338         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2339                                 struct vhost_scsi_tpg, se_tpg);
2340
2341         mutex_lock(&vhost_scsi_mutex);
2342         list_del(&tpg->tv_tpg_list);
2343         mutex_unlock(&vhost_scsi_mutex);
2344         /*
2345          * Release the virtual I_T Nexus for this vhost TPG
2346          */
2347         vhost_scsi_drop_nexus(tpg);
2348         /*
2349          * Deregister the se_tpg from TCM..
2350          */
2351         core_tpg_deregister(se_tpg);
2352         kfree(tpg);
2353 }
2354
2355 static struct se_wwn *
2356 vhost_scsi_make_tport(struct target_fabric_configfs *tf,
2357                      struct config_group *group,
2358                      const char *name)
2359 {
2360         struct vhost_scsi_tport *tport;
2361         char *ptr;
2362         u64 wwpn = 0;
2363         int off = 0;
2364
2365         /* if (vhost_scsi_parse_wwn(name, &wwpn, 1) < 0)
2366                 return ERR_PTR(-EINVAL); */
2367
2368         tport = kzalloc(sizeof(*tport), GFP_KERNEL);
2369         if (!tport) {
2370                 pr_err("Unable to allocate struct vhost_scsi_tport");
2371                 return ERR_PTR(-ENOMEM);
2372         }
2373         tport->tport_wwpn = wwpn;
2374         /*
2375          * Determine the emulated Protocol Identifier and Target Port Name
2376          * based on the incoming configfs directory name.
2377          */
2378         ptr = strstr(name, "naa.");
2379         if (ptr) {
2380                 tport->tport_proto_id = SCSI_PROTOCOL_SAS;
2381                 goto check_len;
2382         }
2383         ptr = strstr(name, "fc.");
2384         if (ptr) {
2385                 tport->tport_proto_id = SCSI_PROTOCOL_FCP;
2386                 off = 3; /* Skip over "fc." */
2387                 goto check_len;
2388         }
2389         ptr = strstr(name, "iqn.");
2390         if (ptr) {
2391                 tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
2392                 goto check_len;
2393         }
2394
2395         pr_err("Unable to locate prefix for emulated Target Port:"
2396                         " %s\n", name);
2397         kfree(tport);
2398         return ERR_PTR(-EINVAL);
2399
2400 check_len:
2401         if (strlen(name) >= VHOST_SCSI_NAMELEN) {
2402                 pr_err("Emulated %s Address: %s, exceeds"
2403                         " max: %d\n", name, vhost_scsi_dump_proto_id(tport),
2404                         VHOST_SCSI_NAMELEN);
2405                 kfree(tport);
2406                 return ERR_PTR(-EINVAL);
2407         }
2408         snprintf(&tport->tport_name[0], VHOST_SCSI_NAMELEN, "%s", &name[off]);
2409
2410         pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target"
2411                 " %s Address: %s\n", vhost_scsi_dump_proto_id(tport), name);
2412
2413         return &tport->tport_wwn;
2414 }
2415
2416 static void vhost_scsi_drop_tport(struct se_wwn *wwn)
2417 {
2418         struct vhost_scsi_tport *tport = container_of(wwn,
2419                                 struct vhost_scsi_tport, tport_wwn);
2420
2421         pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target"
2422                 " %s Address: %s\n", vhost_scsi_dump_proto_id(tport),
2423                 tport->tport_name);
2424
2425         kfree(tport);
2426 }
2427
2428 static ssize_t
2429 vhost_scsi_wwn_version_show(struct config_item *item, char *page)
2430 {
2431         return sprintf(page, "TCM_VHOST fabric module %s on %s/%s"
2432                 "on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
2433                 utsname()->machine);
2434 }
2435
2436 CONFIGFS_ATTR_RO(vhost_scsi_wwn_, version);
2437
2438 static struct configfs_attribute *vhost_scsi_wwn_attrs[] = {
2439         &vhost_scsi_wwn_attr_version,
2440         NULL,
2441 };
2442
2443 static const struct target_core_fabric_ops vhost_scsi_ops = {
2444         .module                         = THIS_MODULE,
2445         .fabric_name                    = "vhost",
2446         .max_data_sg_nents              = VHOST_SCSI_PREALLOC_SGLS,
2447         .tpg_get_wwn                    = vhost_scsi_get_fabric_wwn,
2448         .tpg_get_tag                    = vhost_scsi_get_tpgt,
2449         .tpg_check_demo_mode            = vhost_scsi_check_true,
2450         .tpg_check_demo_mode_cache      = vhost_scsi_check_true,
2451         .tpg_check_demo_mode_write_protect = vhost_scsi_check_false,
2452         .tpg_check_prod_mode_write_protect = vhost_scsi_check_false,
2453         .tpg_check_prot_fabric_only     = vhost_scsi_check_prot_fabric_only,
2454         .tpg_get_inst_index             = vhost_scsi_tpg_get_inst_index,
2455         .release_cmd                    = vhost_scsi_release_cmd,
2456         .check_stop_free                = vhost_scsi_check_stop_free,
2457         .sess_get_index                 = vhost_scsi_sess_get_index,
2458         .sess_get_initiator_sid         = NULL,
2459         .write_pending                  = vhost_scsi_write_pending,
2460         .set_default_node_attributes    = vhost_scsi_set_default_node_attrs,
2461         .get_cmd_state                  = vhost_scsi_get_cmd_state,
2462         .queue_data_in                  = vhost_scsi_queue_data_in,
2463         .queue_status                   = vhost_scsi_queue_status,
2464         .queue_tm_rsp                   = vhost_scsi_queue_tm_rsp,
2465         .aborted_task                   = vhost_scsi_aborted_task,
2466         /*
2467          * Setup callers for generic logic in target_core_fabric_configfs.c
2468          */
2469         .fabric_make_wwn                = vhost_scsi_make_tport,
2470         .fabric_drop_wwn                = vhost_scsi_drop_tport,
2471         .fabric_make_tpg                = vhost_scsi_make_tpg,
2472         .fabric_drop_tpg                = vhost_scsi_drop_tpg,
2473         .fabric_post_link               = vhost_scsi_port_link,
2474         .fabric_pre_unlink              = vhost_scsi_port_unlink,
2475
2476         .tfc_wwn_attrs                  = vhost_scsi_wwn_attrs,
2477         .tfc_tpg_base_attrs             = vhost_scsi_tpg_attrs,
2478         .tfc_tpg_attrib_attrs           = vhost_scsi_tpg_attrib_attrs,
2479 };
2480
2481 static int __init vhost_scsi_init(void)
2482 {
2483         int ret = -ENOMEM;
2484
2485         pr_debug("TCM_VHOST fabric module %s on %s/%s"
2486                 " on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
2487                 utsname()->machine);
2488
2489         /*
2490          * Use our own dedicated workqueue for submitting I/O into
2491          * target core to avoid contention within system_wq.
2492          */
2493         vhost_scsi_workqueue = alloc_workqueue("vhost_scsi", 0, 0);
2494         if (!vhost_scsi_workqueue)
2495                 goto out;
2496
2497         ret = vhost_scsi_register();
2498         if (ret < 0)
2499                 goto out_destroy_workqueue;
2500
2501         ret = target_register_template(&vhost_scsi_ops);
2502         if (ret < 0)
2503                 goto out_vhost_scsi_deregister;
2504
2505         return 0;
2506
2507 out_vhost_scsi_deregister:
2508         vhost_scsi_deregister();
2509 out_destroy_workqueue:
2510         destroy_workqueue(vhost_scsi_workqueue);
2511 out:
2512         return ret;
2513 };
2514
2515 static void vhost_scsi_exit(void)
2516 {
2517         target_unregister_template(&vhost_scsi_ops);
2518         vhost_scsi_deregister();
2519         destroy_workqueue(vhost_scsi_workqueue);
2520 };
2521
2522 MODULE_DESCRIPTION("VHOST_SCSI series fabric driver");
2523 MODULE_ALIAS("tcm_vhost");
2524 MODULE_LICENSE("GPL");
2525 module_init(vhost_scsi_init);
2526 module_exit(vhost_scsi_exit);