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_target_queue_cmd() */
  89         u32 tvc_lun;
  90         /* Pointer to the SGL formatted memory from virtio-scsi */
  91         struct scatterlist *tvc_sgl;
  92         struct scatterlist *tvc_prot_sgl;
  93         struct page **tvc_upages;
  94         /* Pointer to response header iovec */
  95         struct iovec tvc_resp_iov;
  96         /* Pointer to vhost_scsi for our device */
  97         struct vhost_scsi *tvc_vhost;
  98         /* Pointer to vhost_virtqueue for the cmd */
  99         struct vhost_virtqueue *tvc_vq;
 100         /* Pointer to vhost nexus memory */
 101         struct vhost_scsi_nexus *tvc_nexus;
 102         /* The TCM I/O descriptor that is accessed via container_of() */
 103         struct se_cmd tvc_se_cmd;
 104         /* Copy of the incoming SCSI command descriptor block (CDB) */
 105         unsigned char tvc_cdb[VHOST_SCSI_MAX_CDB_SIZE];
 106         /* Sense buffer that will be mapped into outgoing status */
 107         unsigned char tvc_sense_buf[TRANSPORT_SENSE_BUFFER];
 108         /* Completed commands list, serviced from vhost worker thread */
 109         struct llist_node tvc_completion_list;
 110         /* Used to track inflight cmd */
 111         struct vhost_scsi_inflight *inflight;
 112 };
 113
 114 struct vhost_scsi_nexus {
 115         /* Pointer to TCM session for I_T Nexus */
 116         struct se_session *tvn_se_sess;
 117 };
 118
 119 struct vhost_scsi_tpg {
 120         /* Vhost port target portal group tag for TCM */
 121         u16 tport_tpgt;
 122         /* Used to track number of TPG Port/Lun Links wrt to explict I_T Nexus shutdown */
 123         int tv_tpg_port_count;
 124         /* Used for vhost_scsi device reference to tpg_nexus, protected by tv_tpg_mutex */
 125         int tv_tpg_vhost_count;
 126         /* Used for enabling T10-PI with legacy devices */
 127         int tv_fabric_prot_type;
 128         /* list for vhost_scsi_list */
 129         struct list_head tv_tpg_list;
 130         /* Used to protect access for tpg_nexus */
 131         struct mutex tv_tpg_mutex;
 132         /* Pointer to the TCM VHost I_T Nexus for this TPG endpoint */
 133         struct vhost_scsi_nexus *tpg_nexus;
 134         /* Pointer back to vhost_scsi_tport */
 135         struct vhost_scsi_tport *tport;
 136         /* Returned by vhost_scsi_make_tpg() */
 137         struct se_portal_group se_tpg;
 138         /* Pointer back to vhost_scsi, protected by tv_tpg_mutex */
 139         struct vhost_scsi *vhost_scsi;
 140         struct list_head tmf_queue;
 141 };
 142
 143 struct vhost_scsi_tport {
 144         /* SCSI protocol the tport is providing */
 145         u8 tport_proto_id;
 146         /* Binary World Wide unique Port Name for Vhost Target port */
 147         u64 tport_wwpn;
 148         /* ASCII formatted WWPN for Vhost Target port */
 149         char tport_name[VHOST_SCSI_NAMELEN];
 150         /* Returned by vhost_scsi_make_tport() */
 151         struct se_wwn tport_wwn;
 152 };
 153
 154 struct vhost_scsi_evt {
 155         /* event to be sent to guest */
 156         struct virtio_scsi_event event;
 157         /* event list, serviced from vhost worker thread */
 158         struct llist_node list;
 159 };
 160
 161 enum {
 162         VHOST_SCSI_VQ_CTL = 0,
 163         VHOST_SCSI_VQ_EVT = 1,
 164         VHOST_SCSI_VQ_IO = 2,
 165 };
 166
 167 /* Note: can't set VIRTIO_F_VERSION_1 yet, since that implies ANY_LAYOUT. */
 168 enum {
 169         VHOST_SCSI_FEATURES = VHOST_FEATURES | (1ULL << VIRTIO_SCSI_F_HOTPLUG) |
 170                                                (1ULL << VIRTIO_SCSI_F_T10_PI)
 171 };
 172
 173 #define VHOST_SCSI_MAX_TARGET   256
 174 #define VHOST_SCSI_MAX_VQ       128
 175 #define VHOST_SCSI_MAX_EVENT    128
 176
 177 struct vhost_scsi_virtqueue {
 178         struct vhost_virtqueue vq;
 179         /*
 180          * Reference counting for inflight reqs, used for flush operation. At
 181          * each time, one reference tracks new commands submitted, while we
 182          * wait for another one to reach 0.
 183          */
 184         struct vhost_scsi_inflight inflights[2];
 185         /*
 186          * Indicate current inflight in use, protected by vq->mutex.
 187          * Writers must also take dev mutex and flush under it.
 188          */
 189         int inflight_idx;
 190         struct vhost_scsi_cmd *scsi_cmds;
 191         struct sbitmap scsi_tags;
 192         int max_cmds;
 193 };
 194
 195 struct vhost_scsi {
 196         /* Protected by vhost_scsi->dev.mutex */
 197         struct vhost_scsi_tpg **vs_tpg;
 198         char vs_vhost_wwpn[TRANSPORT_IQN_LEN];
 199
 200         struct vhost_dev dev;
 201         struct vhost_scsi_virtqueue vqs[VHOST_SCSI_MAX_VQ];
 202
 203         struct vhost_work vs_completion_work; /* cmd completion work item */
 204         struct llist_head vs_completion_list; /* cmd completion queue */
 205
 206         struct vhost_work vs_event_work; /* evt injection work item */
 207         struct llist_head vs_event_list; /* evt injection queue */
 208
 209         bool vs_events_missed; /* any missed events, protected by vq->mutex */
 210         int vs_events_nr; /* num of pending events, protected by vq->mutex */
 211 };
 212
 213 struct vhost_scsi_tmf {
 214         struct vhost_work vwork;
 215         struct vhost_scsi_tpg *tpg;
 216         struct vhost_scsi *vhost;
 217         struct vhost_scsi_virtqueue *svq;
 218         struct list_head queue_entry;
 219
 220         struct se_cmd se_cmd;
 221         u8 scsi_resp;
 222         struct vhost_scsi_inflight *inflight;
 223         struct iovec resp_iov;
 224         int in_iovs;
 225         int vq_desc;
 226 };
 227
 228 /*
 229  * Context for processing request and control queue operations.
 230  */
 231 struct vhost_scsi_ctx {
 232         int head;
 233         unsigned int out, in;
 234         size_t req_size, rsp_size;
 235         size_t out_size, in_size;
 236         u8 *target, *lunp;
 237         void *req;
 238         struct iov_iter out_iter;
 239 };
 240
 241 /* Global spinlock to protect vhost_scsi TPG list for vhost IOCTL access */
 242 static DEFINE_MUTEX(vhost_scsi_mutex);
 243 static LIST_HEAD(vhost_scsi_list);
 244
 245 static void vhost_scsi_done_inflight(struct kref *kref)
 246 {
 247         struct vhost_scsi_inflight *inflight;
 248
 249         inflight = container_of(kref, struct vhost_scsi_inflight, kref);
 250         complete(&inflight->comp);
 251 }
 252
 253 static void vhost_scsi_init_inflight(struct vhost_scsi *vs,
 254                                     struct vhost_scsi_inflight *old_inflight[])
 255 {
 256         struct vhost_scsi_inflight *new_inflight;
 257         struct vhost_virtqueue *vq;
 258         int idx, i;
 259
 260         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
 261                 vq = &vs->vqs[i].vq;
 262
 263                 mutex_lock(&vq->mutex);
 264
 265                 /* store old infight */
 266                 idx = vs->vqs[i].inflight_idx;
 267                 if (old_inflight)
 268                         old_inflight[i] = &vs->vqs[i].inflights[idx];
 269
 270                 /* setup new infight */
 271                 vs->vqs[i].inflight_idx = idx ^ 1;
 272                 new_inflight = &vs->vqs[i].inflights[idx ^ 1];
 273                 kref_init(&new_inflight->kref);
 274                 init_completion(&new_inflight->comp);
 275
 276                 mutex_unlock(&vq->mutex);
 277         }
 278 }
 279
 280 static struct vhost_scsi_inflight *
 281 vhost_scsi_get_inflight(struct vhost_virtqueue *vq)
 282 {
 283         struct vhost_scsi_inflight *inflight;
 284         struct vhost_scsi_virtqueue *svq;
 285
 286         svq = container_of(vq, struct vhost_scsi_virtqueue, vq);
 287         inflight = &svq->inflights[svq->inflight_idx];
 288         kref_get(&inflight->kref);
 289
 290         return inflight;
 291 }
 292
 293 static void vhost_scsi_put_inflight(struct vhost_scsi_inflight *inflight)
 294 {
 295         kref_put(&inflight->kref, vhost_scsi_done_inflight);
 296 }
 297
 298 static int vhost_scsi_check_true(struct se_portal_group *se_tpg)
 299 {
 300         return 1;
 301 }
 302
 303 static int vhost_scsi_check_false(struct se_portal_group *se_tpg)
 304 {
 305         return 0;
 306 }
 307
 308 static char *vhost_scsi_get_fabric_wwn(struct se_portal_group *se_tpg)
 309 {
 310         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 311                                 struct vhost_scsi_tpg, se_tpg);
 312         struct vhost_scsi_tport *tport = tpg->tport;
 313
 314         return &tport->tport_name[0];
 315 }
 316
 317 static u16 vhost_scsi_get_tpgt(struct se_portal_group *se_tpg)
 318 {
 319         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 320                                 struct vhost_scsi_tpg, se_tpg);
 321         return tpg->tport_tpgt;
 322 }
 323
 324 static int vhost_scsi_check_prot_fabric_only(struct se_portal_group *se_tpg)
 325 {
 326         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 327                                 struct vhost_scsi_tpg, se_tpg);
 328
 329         return tpg->tv_fabric_prot_type;
 330 }
 331
 332 static u32 vhost_scsi_tpg_get_inst_index(struct se_portal_group *se_tpg)
 333 {
 334         return 1;
 335 }
 336
 337 static void vhost_scsi_release_cmd_res(struct se_cmd *se_cmd)
 338 {
 339         struct vhost_scsi_cmd *tv_cmd = container_of(se_cmd,
 340                                 struct vhost_scsi_cmd, tvc_se_cmd);
 341         struct vhost_scsi_virtqueue *svq = container_of(tv_cmd->tvc_vq,
 342                                 struct vhost_scsi_virtqueue, vq);
 343         struct vhost_scsi_inflight *inflight = tv_cmd->inflight;
 344         int i;
 345
 346         if (tv_cmd->tvc_sgl_count) {
 347                 for (i = 0; i < tv_cmd->tvc_sgl_count; i++)
 348                         put_page(sg_page(&tv_cmd->tvc_sgl[i]));
 349         }
 350         if (tv_cmd->tvc_prot_sgl_count) {
 351                 for (i = 0; i < tv_cmd->tvc_prot_sgl_count; i++)
 352                         put_page(sg_page(&tv_cmd->tvc_prot_sgl[i]));
 353         }
 354
 355         sbitmap_clear_bit(&svq->scsi_tags, se_cmd->map_tag);
 356         vhost_scsi_put_inflight(inflight);
 357 }
 358
 359 static void vhost_scsi_release_tmf_res(struct vhost_scsi_tmf *tmf)
 360 {
 361         struct vhost_scsi_tpg *tpg = tmf->tpg;
 362         struct vhost_scsi_inflight *inflight = tmf->inflight;
 363
 364         mutex_lock(&tpg->tv_tpg_mutex);
 365         list_add_tail(&tpg->tmf_queue, &tmf->queue_entry);
 366         mutex_unlock(&tpg->tv_tpg_mutex);
 367         vhost_scsi_put_inflight(inflight);
 368 }
 369
 370 static void vhost_scsi_release_cmd(struct se_cmd *se_cmd)
 371 {
 372         if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB) {
 373                 struct vhost_scsi_tmf *tmf = container_of(se_cmd,
 374                                         struct vhost_scsi_tmf, se_cmd);
 375
 376                 vhost_work_queue(&tmf->vhost->dev, &tmf->vwork);
 377         } else {
 378                 struct vhost_scsi_cmd *cmd = container_of(se_cmd,
 379                                         struct vhost_scsi_cmd, tvc_se_cmd);
 380                 struct vhost_scsi *vs = cmd->tvc_vhost;
 381
 382                 llist_add(&cmd->tvc_completion_list, &vs->vs_completion_list);
 383                 vhost_work_queue(&vs->dev, &vs->vs_completion_work);
 384         }
 385 }
 386
 387 static u32 vhost_scsi_sess_get_index(struct se_session *se_sess)
 388 {
 389         return 0;
 390 }
 391
 392 static int vhost_scsi_write_pending(struct se_cmd *se_cmd)
 393 {
 394         /* Go ahead and process the write immediately */
 395         target_execute_cmd(se_cmd);
 396         return 0;
 397 }
 398
 399 static void vhost_scsi_set_default_node_attrs(struct se_node_acl *nacl)
 400 {
 401         return;
 402 }
 403
 404 static int vhost_scsi_get_cmd_state(struct se_cmd *se_cmd)
 405 {
 406         return 0;
 407 }
 408
 409 static int vhost_scsi_queue_data_in(struct se_cmd *se_cmd)
 410 {
 411         transport_generic_free_cmd(se_cmd, 0);
 412         return 0;
 413 }
 414
 415 static int vhost_scsi_queue_status(struct se_cmd *se_cmd)
 416 {
 417         transport_generic_free_cmd(se_cmd, 0);
 418         return 0;
 419 }
 420
 421 static void vhost_scsi_queue_tm_rsp(struct se_cmd *se_cmd)
 422 {
 423         struct vhost_scsi_tmf *tmf = container_of(se_cmd, struct vhost_scsi_tmf,
 424                                                   se_cmd);
 425
 426         tmf->scsi_resp = se_cmd->se_tmr_req->response;
 427         transport_generic_free_cmd(&tmf->se_cmd, 0);
 428 }
 429
 430 static void vhost_scsi_aborted_task(struct se_cmd *se_cmd)
 431 {
 432         return;
 433 }
 434
 435 static void vhost_scsi_free_evt(struct vhost_scsi *vs, struct vhost_scsi_evt *evt)
 436 {
 437         vs->vs_events_nr--;
 438         kfree(evt);
 439 }
 440
 441 static struct vhost_scsi_evt *
 442 vhost_scsi_allocate_evt(struct vhost_scsi *vs,
 443                        u32 event, u32 reason)
 444 {
 445         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 446         struct vhost_scsi_evt *evt;
 447
 448         if (vs->vs_events_nr > VHOST_SCSI_MAX_EVENT) {
 449                 vs->vs_events_missed = true;
 450                 return NULL;
 451         }
 452
 453         evt = kzalloc(sizeof(*evt), GFP_KERNEL);
 454         if (!evt) {
 455                 vq_err(vq, "Failed to allocate vhost_scsi_evt\n");
 456                 vs->vs_events_missed = true;
 457                 return NULL;
 458         }
 459
 460         evt->event.event = cpu_to_vhost32(vq, event);
 461         evt->event.reason = cpu_to_vhost32(vq, reason);
 462         vs->vs_events_nr++;
 463
 464         return evt;
 465 }
 466
 467 static int vhost_scsi_check_stop_free(struct se_cmd *se_cmd)
 468 {
 469         return target_put_sess_cmd(se_cmd);
 470 }
 471
 472 static void
 473 vhost_scsi_do_evt_work(struct vhost_scsi *vs, struct vhost_scsi_evt *evt)
 474 {
 475         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 476         struct virtio_scsi_event *event = &evt->event;
 477         struct virtio_scsi_event __user *eventp;
 478         unsigned out, in;
 479         int head, ret;
 480
 481         if (!vhost_vq_get_backend(vq)) {
 482                 vs->vs_events_missed = true;
 483                 return;
 484         }
 485
 486 again:
 487         vhost_disable_notify(&vs->dev, vq);
 488         head = vhost_get_vq_desc(vq, vq->iov,
 489                         ARRAY_SIZE(vq->iov), &out, &in,
 490                         NULL, NULL);
 491         if (head < 0) {
 492                 vs->vs_events_missed = true;
 493                 return;
 494         }
 495         if (head == vq->num) {
 496                 if (vhost_enable_notify(&vs->dev, vq))
 497                         goto again;
 498                 vs->vs_events_missed = true;
 499                 return;
 500         }
 501
 502         if ((vq->iov[out].iov_len != sizeof(struct virtio_scsi_event))) {
 503                 vq_err(vq, "Expecting virtio_scsi_event, got %zu bytes\n",
 504                                 vq->iov[out].iov_len);
 505                 vs->vs_events_missed = true;
 506                 return;
 507         }
 508
 509         if (vs->vs_events_missed) {
 510                 event->event |= cpu_to_vhost32(vq, VIRTIO_SCSI_T_EVENTS_MISSED);
 511                 vs->vs_events_missed = false;
 512         }
 513
 514         eventp = vq->iov[out].iov_base;
 515         ret = __copy_to_user(eventp, event, sizeof(*event));
 516         if (!ret)
 517                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 518         else
 519                 vq_err(vq, "Faulted on vhost_scsi_send_event\n");
 520 }
 521
 522 static void vhost_scsi_evt_work(struct vhost_work *work)
 523 {
 524         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 525                                         vs_event_work);
 526         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 527         struct vhost_scsi_evt *evt, *t;
 528         struct llist_node *llnode;
 529
 530         mutex_lock(&vq->mutex);
 531         llnode = llist_del_all(&vs->vs_event_list);
 532         llist_for_each_entry_safe(evt, t, llnode, list) {
 533                 vhost_scsi_do_evt_work(vs, evt);
 534                 vhost_scsi_free_evt(vs, evt);
 535         }
 536         mutex_unlock(&vq->mutex);
 537 }
 538
 539 /* Fill in status and signal that we are done processing this command
 540  *
 541  * This is scheduled in the vhost work queue so we are called with the owner
 542  * process mm and can access the vring.
 543  */
 544 static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
 545 {
 546         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 547                                         vs_completion_work);
 548         DECLARE_BITMAP(signal, VHOST_SCSI_MAX_VQ);
 549         struct virtio_scsi_cmd_resp v_rsp;
 550         struct vhost_scsi_cmd *cmd, *t;
 551         struct llist_node *llnode;
 552         struct se_cmd *se_cmd;
 553         struct iov_iter iov_iter;
 554         int ret, vq;
 555
 556         bitmap_zero(signal, VHOST_SCSI_MAX_VQ);
 557         llnode = llist_del_all(&vs->vs_completion_list);
 558         llist_for_each_entry_safe(cmd, t, llnode, tvc_completion_list) {
 559                 se_cmd = &cmd->tvc_se_cmd;
 560
 561                 pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__,
 562                         cmd, se_cmd->residual_count, se_cmd->scsi_status);
 563
 564                 memset(&v_rsp, 0, sizeof(v_rsp));
 565                 v_rsp.resid = cpu_to_vhost32(cmd->tvc_vq, se_cmd->residual_count);
 566                 /* TODO is status_qualifier field needed? */
 567                 v_rsp.status = se_cmd->scsi_status;
 568                 v_rsp.sense_len = cpu_to_vhost32(cmd->tvc_vq,
 569                                                  se_cmd->scsi_sense_length);
 570                 memcpy(v_rsp.sense, cmd->tvc_sense_buf,
 571                        se_cmd->scsi_sense_length);
 572
 573                 iov_iter_init(&iov_iter, READ, &cmd->tvc_resp_iov,
 574                               cmd->tvc_in_iovs, sizeof(v_rsp));
 575                 ret = copy_to_iter(&v_rsp, sizeof(v_rsp), &iov_iter);
 576                 if (likely(ret == sizeof(v_rsp))) {
 577                         struct vhost_scsi_virtqueue *q;
 578                         vhost_add_used(cmd->tvc_vq, cmd->tvc_vq_desc, 0);
 579                         q = container_of(cmd->tvc_vq, struct vhost_scsi_virtqueue, vq);
 580                         vq = q - vs->vqs;
 581                         __set_bit(vq, signal);
 582                 } else
 583                         pr_err("Faulted on virtio_scsi_cmd_resp\n");
 584
 585                 vhost_scsi_release_cmd_res(se_cmd);
 586         }
 587
 588         vq = -1;
 589         while ((vq = find_next_bit(signal, VHOST_SCSI_MAX_VQ, vq + 1))
 590                 < VHOST_SCSI_MAX_VQ)
 591                 vhost_signal(&vs->dev, &vs->vqs[vq].vq);
 592 }
 593
 594 static struct vhost_scsi_cmd *
 595 vhost_scsi_get_cmd(struct vhost_virtqueue *vq, struct vhost_scsi_tpg *tpg,
 596                    unsigned char *cdb, u64 scsi_tag, u16 lun, u8 task_attr,
 597                    u32 exp_data_len, int data_direction)
 598 {
 599         struct vhost_scsi_virtqueue *svq = container_of(vq,
 600                                         struct vhost_scsi_virtqueue, vq);
 601         struct vhost_scsi_cmd *cmd;
 602         struct vhost_scsi_nexus *tv_nexus;
 603         struct scatterlist *sg, *prot_sg;
 604         struct page **pages;
 605         int tag;
 606
 607         tv_nexus = tpg->tpg_nexus;
 608         if (!tv_nexus) {
 609                 pr_err("Unable to locate active struct vhost_scsi_nexus\n");
 610                 return ERR_PTR(-EIO);
 611         }
 612
 613         tag = sbitmap_get(&svq->scsi_tags);
 614         if (tag < 0) {
 615                 pr_err("Unable to obtain tag for vhost_scsi_cmd\n");
 616                 return ERR_PTR(-ENOMEM);
 617         }
 618
 619         cmd = &svq->scsi_cmds[tag];
 620         sg = cmd->tvc_sgl;
 621         prot_sg = cmd->tvc_prot_sgl;
 622         pages = cmd->tvc_upages;
 623         memset(cmd, 0, sizeof(*cmd));
 624         cmd->tvc_sgl = sg;
 625         cmd->tvc_prot_sgl = prot_sg;
 626         cmd->tvc_upages = pages;
 627         cmd->tvc_se_cmd.map_tag = tag;
 628         cmd->tvc_tag = scsi_tag;
 629         cmd->tvc_lun = lun;
 630         cmd->tvc_task_attr = task_attr;
 631         cmd->tvc_exp_data_len = exp_data_len;
 632         cmd->tvc_data_direction = data_direction;
 633         cmd->tvc_nexus = tv_nexus;
 634         cmd->inflight = vhost_scsi_get_inflight(vq);
 635
 636         memcpy(cmd->tvc_cdb, cdb, VHOST_SCSI_MAX_CDB_SIZE);
 637
 638         return cmd;
 639 }
 640
 641 /*
 642  * Map a user memory range into a scatterlist
 643  *
 644  * Returns the number of scatterlist entries used or -errno on error.
 645  */
 646 static int
 647 vhost_scsi_map_to_sgl(struct vhost_scsi_cmd *cmd,
 648                       struct iov_iter *iter,
 649                       struct scatterlist *sgl,
 650                       bool write)
 651 {
 652         struct page **pages = cmd->tvc_upages;
 653         struct scatterlist *sg = sgl;
 654         ssize_t bytes;
 655         size_t offset;
 656         unsigned int npages = 0;
 657
 658         bytes = iov_iter_get_pages(iter, pages, LONG_MAX,
 659                                 VHOST_SCSI_PREALLOC_UPAGES, &offset);
 660         /* No pages were pinned */
 661         if (bytes <= 0)
 662                 return bytes < 0 ? bytes : -EFAULT;
 663
 664         iov_iter_advance(iter, bytes);
 665
 666         while (bytes) {
 667                 unsigned n = min_t(unsigned, PAGE_SIZE - offset, bytes);
 668                 sg_set_page(sg++, pages[npages++], n, offset);
 669                 bytes -= n;
 670                 offset = 0;
 671         }
 672         return npages;
 673 }
 674
 675 static int
 676 vhost_scsi_calc_sgls(struct iov_iter *iter, size_t bytes, int max_sgls)
 677 {
 678         int sgl_count = 0;
 679
 680         if (!iter || !iter->iov) {
 681                 pr_err("%s: iter->iov is NULL, but expected bytes: %zu"
 682                        " present\n", __func__, bytes);
 683                 return -EINVAL;
 684         }
 685
 686         sgl_count = iov_iter_npages(iter, 0xffff);
 687         if (sgl_count > max_sgls) {
 688                 pr_err("%s: requested sgl_count: %d exceeds pre-allocated"
 689                        " max_sgls: %d\n", __func__, sgl_count, max_sgls);
 690                 return -EINVAL;
 691         }
 692         return sgl_count;
 693 }
 694
 695 static int
 696 vhost_scsi_iov_to_sgl(struct vhost_scsi_cmd *cmd, bool write,
 697                       struct iov_iter *iter,
 698                       struct scatterlist *sg, int sg_count)
 699 {
 700         struct scatterlist *p = sg;
 701         int ret;
 702
 703         while (iov_iter_count(iter)) {
 704                 ret = vhost_scsi_map_to_sgl(cmd, iter, sg, write);
 705                 if (ret < 0) {
 706                         while (p < sg) {
 707                                 struct page *page = sg_page(p++);
 708                                 if (page)
 709                                         put_page(page);
 710                         }
 711                         return ret;
 712                 }
 713                 sg += ret;
 714         }
 715         return 0;
 716 }
 717
 718 static int
 719 vhost_scsi_mapal(struct vhost_scsi_cmd *cmd,
 720                  size_t prot_bytes, struct iov_iter *prot_iter,
 721                  size_t data_bytes, struct iov_iter *data_iter)
 722 {
 723         int sgl_count, ret;
 724         bool write = (cmd->tvc_data_direction == DMA_FROM_DEVICE);
 725
 726         if (prot_bytes) {
 727                 sgl_count = vhost_scsi_calc_sgls(prot_iter, prot_bytes,
 728                                                  VHOST_SCSI_PREALLOC_PROT_SGLS);
 729                 if (sgl_count < 0)
 730                         return sgl_count;
 731
 732                 sg_init_table(cmd->tvc_prot_sgl, sgl_count);
 733                 cmd->tvc_prot_sgl_count = sgl_count;
 734                 pr_debug("%s prot_sg %p prot_sgl_count %u\n", __func__,
 735                          cmd->tvc_prot_sgl, cmd->tvc_prot_sgl_count);
 736
 737                 ret = vhost_scsi_iov_to_sgl(cmd, write, prot_iter,
 738                                             cmd->tvc_prot_sgl,
 739                                             cmd->tvc_prot_sgl_count);
 740                 if (ret < 0) {
 741                         cmd->tvc_prot_sgl_count = 0;
 742                         return ret;
 743                 }
 744         }
 745         sgl_count = vhost_scsi_calc_sgls(data_iter, data_bytes,
 746                                          VHOST_SCSI_PREALLOC_SGLS);
 747         if (sgl_count < 0)
 748                 return sgl_count;
 749
 750         sg_init_table(cmd->tvc_sgl, sgl_count);
 751         cmd->tvc_sgl_count = sgl_count;
 752         pr_debug("%s data_sg %p data_sgl_count %u\n", __func__,
 753                   cmd->tvc_sgl, cmd->tvc_sgl_count);
 754
 755         ret = vhost_scsi_iov_to_sgl(cmd, write, data_iter,
 756                                     cmd->tvc_sgl, cmd->tvc_sgl_count);
 757         if (ret < 0) {
 758                 cmd->tvc_sgl_count = 0;
 759                 return ret;
 760         }
 761         return 0;
 762 }
 763
 764 static int vhost_scsi_to_tcm_attr(int attr)
 765 {
 766         switch (attr) {
 767         case VIRTIO_SCSI_S_SIMPLE:
 768                 return TCM_SIMPLE_TAG;
 769         case VIRTIO_SCSI_S_ORDERED:
 770                 return TCM_ORDERED_TAG;
 771         case VIRTIO_SCSI_S_HEAD:
 772                 return TCM_HEAD_TAG;
 773         case VIRTIO_SCSI_S_ACA:
 774                 return TCM_ACA_TAG;
 775         default:
 776                 break;
 777         }
 778         return TCM_SIMPLE_TAG;
 779 }
 780
 781 static void vhost_scsi_target_queue_cmd(struct vhost_scsi_cmd *cmd)
 782 {
 783         struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
 784         struct vhost_scsi_nexus *tv_nexus;
 785         struct scatterlist *sg_ptr, *sg_prot_ptr = NULL;
 786
 787         /* FIXME: BIDI operation */
 788         if (cmd->tvc_sgl_count) {
 789                 sg_ptr = cmd->tvc_sgl;
 790
 791                 if (cmd->tvc_prot_sgl_count)
 792                         sg_prot_ptr = cmd->tvc_prot_sgl;
 793                 else
 794                         se_cmd->prot_pto = true;
 795         } else {
 796                 sg_ptr = NULL;
 797         }
 798         tv_nexus = cmd->tvc_nexus;
 799
 800         se_cmd->tag = 0;
 801         target_init_cmd(se_cmd, tv_nexus->tvn_se_sess, &cmd->tvc_sense_buf[0],
 802                         cmd->tvc_lun, cmd->tvc_exp_data_len,
 803                         vhost_scsi_to_tcm_attr(cmd->tvc_task_attr),
 804                         cmd->tvc_data_direction, TARGET_SCF_ACK_KREF);
 805
 806         if (target_submit_prep(se_cmd, cmd->tvc_cdb, sg_ptr,
 807                                cmd->tvc_sgl_count, NULL, 0, sg_prot_ptr,
 808                                cmd->tvc_prot_sgl_count, GFP_KERNEL))
 809                 return;
 810
 811         target_queue_submission(se_cmd);
 812 }
 813
 814 static void
 815 vhost_scsi_send_bad_target(struct vhost_scsi *vs,
 816                            struct vhost_virtqueue *vq,
 817                            int head, unsigned out)
 818 {
 819         struct virtio_scsi_cmd_resp __user *resp;
 820         struct virtio_scsi_cmd_resp rsp;
 821         int ret;
 822
 823         memset(&rsp, 0, sizeof(rsp));
 824         rsp.response = VIRTIO_SCSI_S_BAD_TARGET;
 825         resp = vq->iov[out].iov_base;
 826         ret = __copy_to_user(resp, &rsp, sizeof(rsp));
 827         if (!ret)
 828                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 829         else
 830                 pr_err("Faulted on virtio_scsi_cmd_resp\n");
 831 }
 832
 833 static int
 834 vhost_scsi_get_desc(struct vhost_scsi *vs, struct vhost_virtqueue *vq,
 835                     struct vhost_scsi_ctx *vc)
 836 {
 837         int ret = -ENXIO;
 838
 839         vc->head = vhost_get_vq_desc(vq, vq->iov,
 840                                      ARRAY_SIZE(vq->iov), &vc->out, &vc->in,
 841                                      NULL, NULL);
 842
 843         pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n",
 844                  vc->head, vc->out, vc->in);
 845
 846         /* On error, stop handling until the next kick. */
 847         if (unlikely(vc->head < 0))
 848                 goto done;
 849
 850         /* Nothing new?  Wait for eventfd to tell us they refilled. */
 851         if (vc->head == vq->num) {
 852                 if (unlikely(vhost_enable_notify(&vs->dev, vq))) {
 853                         vhost_disable_notify(&vs->dev, vq);
 854                         ret = -EAGAIN;
 855                 }
 856                 goto done;
 857         }
 858
 859         /*
 860          * Get the size of request and response buffers.
 861          * FIXME: Not correct for BIDI operation
 862          */
 863         vc->out_size = iov_length(vq->iov, vc->out);
 864         vc->in_size = iov_length(&vq->iov[vc->out], vc->in);
 865
 866         /*
 867          * Copy over the virtio-scsi request header, which for a
 868          * ANY_LAYOUT enabled guest may span multiple iovecs, or a
 869          * single iovec may contain both the header + outgoing
 870          * WRITE payloads.
 871          *
 872          * copy_from_iter() will advance out_iter, so that it will
 873          * point at the start of the outgoing WRITE payload, if
 874          * DMA_TO_DEVICE is set.
 875          */
 876         iov_iter_init(&vc->out_iter, WRITE, vq->iov, vc->out, vc->out_size);
 877         ret = 0;
 878
 879 done:
 880         return ret;
 881 }
 882
 883 static int
 884 vhost_scsi_chk_size(struct vhost_virtqueue *vq, struct vhost_scsi_ctx *vc)
 885 {
 886         if (unlikely(vc->in_size < vc->rsp_size)) {
 887                 vq_err(vq,
 888                        "Response buf too small, need min %zu bytes got %zu",
 889                        vc->rsp_size, vc->in_size);
 890                 return -EINVAL;
 891         } else if (unlikely(vc->out_size < vc->req_size)) {
 892                 vq_err(vq,
 893                        "Request buf too small, need min %zu bytes got %zu",
 894                        vc->req_size, vc->out_size);
 895                 return -EIO;
 896         }
 897
 898         return 0;
 899 }
 900
 901 static int
 902 vhost_scsi_get_req(struct vhost_virtqueue *vq, struct vhost_scsi_ctx *vc,
 903                    struct vhost_scsi_tpg **tpgp)
 904 {
 905         int ret = -EIO;
 906
 907         if (unlikely(!copy_from_iter_full(vc->req, vc->req_size,
 908                                           &vc->out_iter))) {
 909                 vq_err(vq, "Faulted on copy_from_iter_full\n");
 910         } else if (unlikely(*vc->lunp != 1)) {
 911                 /* virtio-scsi spec requires byte 0 of the lun to be 1 */
 912                 vq_err(vq, "Illegal virtio-scsi lun: %u\n", *vc->lunp);
 913         } else {
 914                 struct vhost_scsi_tpg **vs_tpg, *tpg;
 915
 916                 vs_tpg = vhost_vq_get_backend(vq);      /* validated at handler entry */
 917
 918                 tpg = READ_ONCE(vs_tpg[*vc->target]);
 919                 if (unlikely(!tpg)) {
 920                         vq_err(vq, "Target 0x%x does not exist\n", *vc->target);
 921                 } else {
 922                         if (tpgp)
 923                                 *tpgp = tpg;
 924                         ret = 0;
 925                 }
 926         }
 927
 928         return ret;
 929 }
 930
 931 static u16 vhost_buf_to_lun(u8 *lun_buf)
 932 {
 933         return ((lun_buf[2] << 8) | lun_buf[3]) & 0x3FFF;
 934 }
 935
 936 static void
 937 vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
 938 {
 939         struct vhost_scsi_tpg **vs_tpg, *tpg;
 940         struct virtio_scsi_cmd_req v_req;
 941         struct virtio_scsi_cmd_req_pi v_req_pi;
 942         struct vhost_scsi_ctx vc;
 943         struct vhost_scsi_cmd *cmd;
 944         struct iov_iter in_iter, prot_iter, data_iter;
 945         u64 tag;
 946         u32 exp_data_len, data_direction;
 947         int ret, prot_bytes, c = 0;
 948         u16 lun;
 949         u8 task_attr;
 950         bool t10_pi = vhost_has_feature(vq, VIRTIO_SCSI_F_T10_PI);
 951         void *cdb;
 952
 953         mutex_lock(&vq->mutex);
 954         /*
 955          * We can handle the vq only after the endpoint is setup by calling the
 956          * VHOST_SCSI_SET_ENDPOINT ioctl.
 957          */
 958         vs_tpg = vhost_vq_get_backend(vq);
 959         if (!vs_tpg)
 960                 goto out;
 961
 962         memset(&vc, 0, sizeof(vc));
 963         vc.rsp_size = sizeof(struct virtio_scsi_cmd_resp);
 964
 965         vhost_disable_notify(&vs->dev, vq);
 966
 967         do {
 968                 ret = vhost_scsi_get_desc(vs, vq, &vc);
 969                 if (ret)
 970                         goto err;
 971
 972                 /*
 973                  * Setup pointers and values based upon different virtio-scsi
 974                  * request header if T10_PI is enabled in KVM guest.
 975                  */
 976                 if (t10_pi) {
 977                         vc.req = &v_req_pi;
 978                         vc.req_size = sizeof(v_req_pi);
 979                         vc.lunp = &v_req_pi.lun[0];
 980                         vc.target = &v_req_pi.lun[1];
 981                 } else {
 982                         vc.req = &v_req;
 983                         vc.req_size = sizeof(v_req);
 984                         vc.lunp = &v_req.lun[0];
 985                         vc.target = &v_req.lun[1];
 986                 }
 987
 988                 /*
 989                  * Validate the size of request and response buffers.
 990                  * Check for a sane response buffer so we can report
 991                  * early errors back to the guest.
 992                  */
 993                 ret = vhost_scsi_chk_size(vq, &vc);
 994                 if (ret)
 995                         goto err;
 996
 997                 ret = vhost_scsi_get_req(vq, &vc, &tpg);
 998                 if (ret)
 999                         goto err;
1000
1001                 ret = -EIO;     /* bad target on any error from here on */
1002
1003                 /*
1004                  * Determine data_direction by calculating the total outgoing
1005                  * iovec sizes + incoming iovec sizes vs. virtio-scsi request +
1006                  * response headers respectively.
1007                  *
1008                  * For DMA_TO_DEVICE this is out_iter, which is already pointing
1009                  * to the right place.
1010                  *
1011                  * For DMA_FROM_DEVICE, the iovec will be just past the end
1012                  * of the virtio-scsi response header in either the same
1013                  * or immediately following iovec.
1014                  *
1015                  * Any associated T10_PI bytes for the outgoing / incoming
1016                  * payloads are included in calculation of exp_data_len here.
1017                  */
1018                 prot_bytes = 0;
1019
1020                 if (vc.out_size > vc.req_size) {
1021                         data_direction = DMA_TO_DEVICE;
1022                         exp_data_len = vc.out_size - vc.req_size;
1023                         data_iter = vc.out_iter;
1024                 } else if (vc.in_size > vc.rsp_size) {
1025                         data_direction = DMA_FROM_DEVICE;
1026                         exp_data_len = vc.in_size - vc.rsp_size;
1027
1028                         iov_iter_init(&in_iter, READ, &vq->iov[vc.out], vc.in,
1029                                       vc.rsp_size + exp_data_len);
1030                         iov_iter_advance(&in_iter, vc.rsp_size);
1031                         data_iter = in_iter;
1032                 } else {
1033                         data_direction = DMA_NONE;
1034                         exp_data_len = 0;
1035                 }
1036                 /*
1037                  * If T10_PI header + payload is present, setup prot_iter values
1038                  * and recalculate data_iter for vhost_scsi_mapal() mapping to
1039                  * host scatterlists via get_user_pages_fast().
1040                  */
1041                 if (t10_pi) {
1042                         if (v_req_pi.pi_bytesout) {
1043                                 if (data_direction != DMA_TO_DEVICE) {
1044                                         vq_err(vq, "Received non zero pi_bytesout,"
1045                                                 " but wrong data_direction\n");
1046                                         goto err;
1047                                 }
1048                                 prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesout);
1049                         } else if (v_req_pi.pi_bytesin) {
1050                                 if (data_direction != DMA_FROM_DEVICE) {
1051                                         vq_err(vq, "Received non zero pi_bytesin,"
1052                                                 " but wrong data_direction\n");
1053                                         goto err;
1054                                 }
1055                                 prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesin);
1056                         }
1057                         /*
1058                          * Set prot_iter to data_iter and truncate it to
1059                          * prot_bytes, and advance data_iter past any
1060                          * preceeding prot_bytes that may be present.
1061                          *
1062                          * Also fix up the exp_data_len to reflect only the
1063                          * actual data payload length.
1064                          */
1065                         if (prot_bytes) {
1066                                 exp_data_len -= prot_bytes;
1067                                 prot_iter = data_iter;
1068                                 iov_iter_truncate(&prot_iter, prot_bytes);
1069                                 iov_iter_advance(&data_iter, prot_bytes);
1070                         }
1071                         tag = vhost64_to_cpu(vq, v_req_pi.tag);
1072                         task_attr = v_req_pi.task_attr;
1073                         cdb = &v_req_pi.cdb[0];
1074                         lun = vhost_buf_to_lun(v_req_pi.lun);
1075                 } else {
1076                         tag = vhost64_to_cpu(vq, v_req.tag);
1077                         task_attr = v_req.task_attr;
1078                         cdb = &v_req.cdb[0];
1079                         lun = vhost_buf_to_lun(v_req.lun);
1080                 }
1081                 /*
1082                  * Check that the received CDB size does not exceeded our
1083                  * hardcoded max for vhost-scsi, then get a pre-allocated
1084                  * cmd descriptor for the new virtio-scsi tag.
1085                  *
1086                  * TODO what if cdb was too small for varlen cdb header?
1087                  */
1088                 if (unlikely(scsi_command_size(cdb) > VHOST_SCSI_MAX_CDB_SIZE)) {
1089                         vq_err(vq, "Received SCSI CDB with command_size: %d that"
1090                                 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1091                                 scsi_command_size(cdb), VHOST_SCSI_MAX_CDB_SIZE);
1092                                 goto err;
1093                 }
1094                 cmd = vhost_scsi_get_cmd(vq, tpg, cdb, tag, lun, task_attr,
1095                                          exp_data_len + prot_bytes,
1096                                          data_direction);
1097                 if (IS_ERR(cmd)) {
1098                         vq_err(vq, "vhost_scsi_get_cmd failed %ld\n",
1099                                PTR_ERR(cmd));
1100                         goto err;
1101                 }
1102                 cmd->tvc_vhost = vs;
1103                 cmd->tvc_vq = vq;
1104                 cmd->tvc_resp_iov = vq->iov[vc.out];
1105                 cmd->tvc_in_iovs = vc.in;
1106
1107                 pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n",
1108                          cmd->tvc_cdb[0], cmd->tvc_lun);
1109                 pr_debug("cmd: %p exp_data_len: %d, prot_bytes: %d data_direction:"
1110                          " %d\n", cmd, exp_data_len, prot_bytes, data_direction);
1111
1112                 if (data_direction != DMA_NONE) {
1113                         if (unlikely(vhost_scsi_mapal(cmd, prot_bytes,
1114                                                       &prot_iter, exp_data_len,
1115                                                       &data_iter))) {
1116                                 vq_err(vq, "Failed to map iov to sgl\n");
1117                                 vhost_scsi_release_cmd_res(&cmd->tvc_se_cmd);
1118                                 goto err;
1119                         }
1120                 }
1121                 /*
1122                  * Save the descriptor from vhost_get_vq_desc() to be used to
1123                  * complete the virtio-scsi request in TCM callback context via
1124                  * vhost_scsi_queue_data_in() and vhost_scsi_queue_status()
1125                  */
1126                 cmd->tvc_vq_desc = vc.head;
1127                 vhost_scsi_target_queue_cmd(cmd);
1128                 ret = 0;
1129 err:
1130                 /*
1131                  * ENXIO:  No more requests, or read error, wait for next kick
1132                  * EINVAL: Invalid response buffer, drop the request
1133                  * EIO:    Respond with bad target
1134                  * EAGAIN: Pending request
1135                  */
1136                 if (ret == -ENXIO)
1137                         break;
1138                 else if (ret == -EIO)
1139                         vhost_scsi_send_bad_target(vs, vq, vc.head, vc.out);
1140         } while (likely(!vhost_exceeds_weight(vq, ++c, 0)));
1141 out:
1142         mutex_unlock(&vq->mutex);
1143 }
1144
1145 static void
1146 vhost_scsi_send_tmf_resp(struct vhost_scsi *vs, struct vhost_virtqueue *vq,
1147                          int in_iovs, int vq_desc, struct iovec *resp_iov,
1148                          int tmf_resp_code)
1149 {
1150         struct virtio_scsi_ctrl_tmf_resp rsp;
1151         struct iov_iter iov_iter;
1152         int ret;
1153
1154         pr_debug("%s\n", __func__);
1155         memset(&rsp, 0, sizeof(rsp));
1156         rsp.response = tmf_resp_code;
1157
1158         iov_iter_init(&iov_iter, READ, resp_iov, in_iovs, sizeof(rsp));
1159
1160         ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter);
1161         if (likely(ret == sizeof(rsp)))
1162                 vhost_add_used_and_signal(&vs->dev, vq, vq_desc, 0);
1163         else
1164                 pr_err("Faulted on virtio_scsi_ctrl_tmf_resp\n");
1165 }
1166
1167 static void vhost_scsi_tmf_resp_work(struct vhost_work *work)
1168 {
1169         struct vhost_scsi_tmf *tmf = container_of(work, struct vhost_scsi_tmf,
1170                                                   vwork);
1171         int resp_code;
1172
1173         if (tmf->scsi_resp == TMR_FUNCTION_COMPLETE)
1174                 resp_code = VIRTIO_SCSI_S_FUNCTION_SUCCEEDED;
1175         else
1176                 resp_code = VIRTIO_SCSI_S_FUNCTION_REJECTED;
1177
1178         vhost_scsi_send_tmf_resp(tmf->vhost, &tmf->svq->vq, tmf->in_iovs,
1179                                  tmf->vq_desc, &tmf->resp_iov, resp_code);
1180         vhost_scsi_release_tmf_res(tmf);
1181 }
1182
1183 static void
1184 vhost_scsi_handle_tmf(struct vhost_scsi *vs, struct vhost_scsi_tpg *tpg,
1185                       struct vhost_virtqueue *vq,
1186                       struct virtio_scsi_ctrl_tmf_req *vtmf,
1187                       struct vhost_scsi_ctx *vc)
1188 {
1189         struct vhost_scsi_virtqueue *svq = container_of(vq,
1190                                         struct vhost_scsi_virtqueue, vq);
1191         struct vhost_scsi_tmf *tmf;
1192
1193         if (vhost32_to_cpu(vq, vtmf->subtype) !=
1194             VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET)
1195                 goto send_reject;
1196
1197         if (!tpg->tpg_nexus || !tpg->tpg_nexus->tvn_se_sess) {
1198                 pr_err("Unable to locate active struct vhost_scsi_nexus for LUN RESET.\n");
1199                 goto send_reject;
1200         }
1201
1202         mutex_lock(&tpg->tv_tpg_mutex);
1203         if (list_empty(&tpg->tmf_queue)) {
1204                 pr_err("Missing reserve TMF. Could not handle LUN RESET.\n");
1205                 mutex_unlock(&tpg->tv_tpg_mutex);
1206                 goto send_reject;
1207         }
1208
1209         tmf = list_first_entry(&tpg->tmf_queue, struct vhost_scsi_tmf,
1210                                queue_entry);
1211         list_del_init(&tmf->queue_entry);
1212         mutex_unlock(&tpg->tv_tpg_mutex);
1213
1214         tmf->tpg = tpg;
1215         tmf->vhost = vs;
1216         tmf->svq = svq;
1217         tmf->resp_iov = vq->iov[vc->out];
1218         tmf->vq_desc = vc->head;
1219         tmf->in_iovs = vc->in;
1220         tmf->inflight = vhost_scsi_get_inflight(vq);
1221
1222         if (target_submit_tmr(&tmf->se_cmd, tpg->tpg_nexus->tvn_se_sess, NULL,
1223                               vhost_buf_to_lun(vtmf->lun), NULL,
1224                               TMR_LUN_RESET, GFP_KERNEL, 0,
1225                               TARGET_SCF_ACK_KREF) < 0) {
1226                 vhost_scsi_release_tmf_res(tmf);
1227                 goto send_reject;
1228         }
1229
1230         return;
1231
1232 send_reject:
1233         vhost_scsi_send_tmf_resp(vs, vq, vc->in, vc->head, &vq->iov[vc->out],
1234                                  VIRTIO_SCSI_S_FUNCTION_REJECTED);
1235 }
1236
1237 static void
1238 vhost_scsi_send_an_resp(struct vhost_scsi *vs,
1239                         struct vhost_virtqueue *vq,
1240                         struct vhost_scsi_ctx *vc)
1241 {
1242         struct virtio_scsi_ctrl_an_resp rsp;
1243         struct iov_iter iov_iter;
1244         int ret;
1245
1246         pr_debug("%s\n", __func__);
1247         memset(&rsp, 0, sizeof(rsp));   /* event_actual = 0 */
1248         rsp.response = VIRTIO_SCSI_S_OK;
1249
1250         iov_iter_init(&iov_iter, READ, &vq->iov[vc->out], vc->in, sizeof(rsp));
1251
1252         ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter);
1253         if (likely(ret == sizeof(rsp)))
1254                 vhost_add_used_and_signal(&vs->dev, vq, vc->head, 0);
1255         else
1256                 pr_err("Faulted on virtio_scsi_ctrl_an_resp\n");
1257 }
1258
1259 static void
1260 vhost_scsi_ctl_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
1261 {
1262         struct vhost_scsi_tpg *tpg;
1263         union {
1264                 __virtio32 type;
1265                 struct virtio_scsi_ctrl_an_req an;
1266                 struct virtio_scsi_ctrl_tmf_req tmf;
1267         } v_req;
1268         struct vhost_scsi_ctx vc;
1269         size_t typ_size;
1270         int ret, c = 0;
1271
1272         mutex_lock(&vq->mutex);
1273         /*
1274          * We can handle the vq only after the endpoint is setup by calling the
1275          * VHOST_SCSI_SET_ENDPOINT ioctl.
1276          */
1277         if (!vhost_vq_get_backend(vq))
1278                 goto out;
1279
1280         memset(&vc, 0, sizeof(vc));
1281
1282         vhost_disable_notify(&vs->dev, vq);
1283
1284         do {
1285                 ret = vhost_scsi_get_desc(vs, vq, &vc);
1286                 if (ret)
1287                         goto err;
1288
1289                 /*
1290                  * Get the request type first in order to setup
1291                  * other parameters dependent on the type.
1292                  */
1293                 vc.req = &v_req.type;
1294                 typ_size = sizeof(v_req.type);
1295
1296                 if (unlikely(!copy_from_iter_full(vc.req, typ_size,
1297                                                   &vc.out_iter))) {
1298                         vq_err(vq, "Faulted on copy_from_iter tmf type\n");
1299                         /*
1300                          * The size of the response buffer depends on the
1301                          * request type and must be validated against it.
1302                          * Since the request type is not known, don't send
1303                          * a response.
1304                          */
1305                         continue;
1306                 }
1307
1308                 switch (vhost32_to_cpu(vq, v_req.type)) {
1309                 case VIRTIO_SCSI_T_TMF:
1310                         vc.req = &v_req.tmf;
1311                         vc.req_size = sizeof(struct virtio_scsi_ctrl_tmf_req);
1312                         vc.rsp_size = sizeof(struct virtio_scsi_ctrl_tmf_resp);
1313                         vc.lunp = &v_req.tmf.lun[0];
1314                         vc.target = &v_req.tmf.lun[1];
1315                         break;
1316                 case VIRTIO_SCSI_T_AN_QUERY:
1317                 case VIRTIO_SCSI_T_AN_SUBSCRIBE:
1318                         vc.req = &v_req.an;
1319                         vc.req_size = sizeof(struct virtio_scsi_ctrl_an_req);
1320                         vc.rsp_size = sizeof(struct virtio_scsi_ctrl_an_resp);
1321                         vc.lunp = &v_req.an.lun[0];
1322                         vc.target = NULL;
1323                         break;
1324                 default:
1325                         vq_err(vq, "Unknown control request %d", v_req.type);
1326                         continue;
1327                 }
1328
1329                 /*
1330                  * Validate the size of request and response buffers.
1331                  * Check for a sane response buffer so we can report
1332                  * early errors back to the guest.
1333                  */
1334                 ret = vhost_scsi_chk_size(vq, &vc);
1335                 if (ret)
1336                         goto err;
1337
1338                 /*
1339                  * Get the rest of the request now that its size is known.
1340                  */
1341                 vc.req += typ_size;
1342                 vc.req_size -= typ_size;
1343
1344                 ret = vhost_scsi_get_req(vq, &vc, &tpg);
1345                 if (ret)
1346                         goto err;
1347
1348                 if (v_req.type == VIRTIO_SCSI_T_TMF)
1349                         vhost_scsi_handle_tmf(vs, tpg, vq, &v_req.tmf, &vc);
1350                 else
1351                         vhost_scsi_send_an_resp(vs, vq, &vc);
1352 err:
1353                 /*
1354                  * ENXIO:  No more requests, or read error, wait for next kick
1355                  * EINVAL: Invalid response buffer, drop the request
1356                  * EIO:    Respond with bad target
1357                  * EAGAIN: Pending request
1358                  */
1359                 if (ret == -ENXIO)
1360                         break;
1361                 else if (ret == -EIO)
1362                         vhost_scsi_send_bad_target(vs, vq, vc.head, vc.out);
1363         } while (likely(!vhost_exceeds_weight(vq, ++c, 0)));
1364 out:
1365         mutex_unlock(&vq->mutex);
1366 }
1367
1368 static void vhost_scsi_ctl_handle_kick(struct vhost_work *work)
1369 {
1370         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1371                                                 poll.work);
1372         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1373
1374         pr_debug("%s: The handling func for control queue.\n", __func__);
1375         vhost_scsi_ctl_handle_vq(vs, vq);
1376 }
1377
1378 static void
1379 vhost_scsi_send_evt(struct vhost_scsi *vs,
1380                    struct vhost_scsi_tpg *tpg,
1381                    struct se_lun *lun,
1382                    u32 event,
1383                    u32 reason)
1384 {
1385         struct vhost_scsi_evt *evt;
1386
1387         evt = vhost_scsi_allocate_evt(vs, event, reason);
1388         if (!evt)
1389                 return;
1390
1391         if (tpg && lun) {
1392                 /* TODO: share lun setup code with virtio-scsi.ko */
1393                 /*
1394                  * Note: evt->event is zeroed when we allocate it and
1395                  * lun[4-7] need to be zero according to virtio-scsi spec.
1396                  */
1397                 evt->event.lun[0] = 0x01;
1398                 evt->event.lun[1] = tpg->tport_tpgt;
1399                 if (lun->unpacked_lun >= 256)
1400                         evt->event.lun[2] = lun->unpacked_lun >> 8 | 0x40 ;
1401                 evt->event.lun[3] = lun->unpacked_lun & 0xFF;
1402         }
1403
1404         llist_add(&evt->list, &vs->vs_event_list);
1405         vhost_work_queue(&vs->dev, &vs->vs_event_work);
1406 }
1407
1408 static void vhost_scsi_evt_handle_kick(struct vhost_work *work)
1409 {
1410         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1411                                                 poll.work);
1412         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1413
1414         mutex_lock(&vq->mutex);
1415         if (!vhost_vq_get_backend(vq))
1416                 goto out;
1417
1418         if (vs->vs_events_missed)
1419                 vhost_scsi_send_evt(vs, NULL, NULL, VIRTIO_SCSI_T_NO_EVENT, 0);
1420 out:
1421         mutex_unlock(&vq->mutex);
1422 }
1423
1424 static void vhost_scsi_handle_kick(struct vhost_work *work)
1425 {
1426         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1427                                                 poll.work);
1428         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1429
1430         vhost_scsi_handle_vq(vs, vq);
1431 }
1432
1433 static void vhost_scsi_flush_vq(struct vhost_scsi *vs, int index)
1434 {
1435         vhost_poll_flush(&vs->vqs[index].vq.poll);
1436 }
1437
1438 /* Callers must hold dev mutex */
1439 static void vhost_scsi_flush(struct vhost_scsi *vs)
1440 {
1441         struct vhost_scsi_inflight *old_inflight[VHOST_SCSI_MAX_VQ];
1442         int i;
1443
1444         /* Init new inflight and remember the old inflight */
1445         vhost_scsi_init_inflight(vs, old_inflight);
1446
1447         /*
1448          * The inflight->kref was initialized to 1. We decrement it here to
1449          * indicate the start of the flush operation so that it will reach 0
1450          * when all the reqs are finished.
1451          */
1452         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1453                 kref_put(&old_inflight[i]->kref, vhost_scsi_done_inflight);
1454
1455         /* Flush both the vhost poll and vhost work */
1456         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1457                 vhost_scsi_flush_vq(vs, i);
1458         vhost_work_flush(&vs->dev, &vs->vs_completion_work);
1459         vhost_work_flush(&vs->dev, &vs->vs_event_work);
1460
1461         /* Wait for all reqs issued before the flush to be finished */
1462         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1463                 wait_for_completion(&old_inflight[i]->comp);
1464 }
1465
1466 static void vhost_scsi_destroy_vq_cmds(struct vhost_virtqueue *vq)
1467 {
1468         struct vhost_scsi_virtqueue *svq = container_of(vq,
1469                                         struct vhost_scsi_virtqueue, vq);
1470         struct vhost_scsi_cmd *tv_cmd;
1471         unsigned int i;
1472
1473         if (!svq->scsi_cmds)
1474                 return;
1475
1476         for (i = 0; i < svq->max_cmds; i++) {
1477                 tv_cmd = &svq->scsi_cmds[i];
1478
1479                 kfree(tv_cmd->tvc_sgl);
1480                 kfree(tv_cmd->tvc_prot_sgl);
1481                 kfree(tv_cmd->tvc_upages);
1482         }
1483
1484         sbitmap_free(&svq->scsi_tags);
1485         kfree(svq->scsi_cmds);
1486         svq->scsi_cmds = NULL;
1487 }
1488
1489 static int vhost_scsi_setup_vq_cmds(struct vhost_virtqueue *vq, int max_cmds)
1490 {
1491         struct vhost_scsi_virtqueue *svq = container_of(vq,
1492                                         struct vhost_scsi_virtqueue, vq);
1493         struct vhost_scsi_cmd *tv_cmd;
1494         unsigned int i;
1495
1496         if (svq->scsi_cmds)
1497                 return 0;
1498
1499         if (sbitmap_init_node(&svq->scsi_tags, max_cmds, -1, GFP_KERNEL,
1500                               NUMA_NO_NODE, false, true))
1501                 return -ENOMEM;
1502         svq->max_cmds = max_cmds;
1503
1504         svq->scsi_cmds = kcalloc(max_cmds, sizeof(*tv_cmd), GFP_KERNEL);
1505         if (!svq->scsi_cmds) {
1506                 sbitmap_free(&svq->scsi_tags);
1507                 return -ENOMEM;
1508         }
1509
1510         for (i = 0; i < max_cmds; i++) {
1511                 tv_cmd = &svq->scsi_cmds[i];
1512
1513                 tv_cmd->tvc_sgl = kcalloc(VHOST_SCSI_PREALLOC_SGLS,
1514                                           sizeof(struct scatterlist),
1515                                           GFP_KERNEL);
1516                 if (!tv_cmd->tvc_sgl) {
1517                         pr_err("Unable to allocate tv_cmd->tvc_sgl\n");
1518                         goto out;
1519                 }
1520
1521                 tv_cmd->tvc_upages = kcalloc(VHOST_SCSI_PREALLOC_UPAGES,
1522                                              sizeof(struct page *),
1523                                              GFP_KERNEL);
1524                 if (!tv_cmd->tvc_upages) {
1525                         pr_err("Unable to allocate tv_cmd->tvc_upages\n");
1526                         goto out;
1527                 }
1528
1529                 tv_cmd->tvc_prot_sgl = kcalloc(VHOST_SCSI_PREALLOC_PROT_SGLS,
1530                                                sizeof(struct scatterlist),
1531                                                GFP_KERNEL);
1532                 if (!tv_cmd->tvc_prot_sgl) {
1533                         pr_err("Unable to allocate tv_cmd->tvc_prot_sgl\n");
1534                         goto out;
1535                 }
1536         }
1537         return 0;
1538 out:
1539         vhost_scsi_destroy_vq_cmds(vq);
1540         return -ENOMEM;
1541 }
1542
1543 /*
1544  * Called from vhost_scsi_ioctl() context to walk the list of available
1545  * vhost_scsi_tpg with an active struct vhost_scsi_nexus
1546  *
1547  *  The lock nesting rule is:
1548  *    vhost_scsi_mutex -> vs->dev.mutex -> tpg->tv_tpg_mutex -> vq->mutex
1549  */
1550 static int
1551 vhost_scsi_set_endpoint(struct vhost_scsi *vs,
1552                         struct vhost_scsi_target *t)
1553 {
1554         struct se_portal_group *se_tpg;
1555         struct vhost_scsi_tport *tv_tport;
1556         struct vhost_scsi_tpg *tpg;
1557         struct vhost_scsi_tpg **vs_tpg;
1558         struct vhost_virtqueue *vq;
1559         int index, ret, i, len;
1560         bool match = false;
1561
1562         mutex_lock(&vhost_scsi_mutex);
1563         mutex_lock(&vs->dev.mutex);
1564
1565         /* Verify that ring has been setup correctly. */
1566         for (index = 0; index < vs->dev.nvqs; ++index) {
1567                 /* Verify that ring has been setup correctly. */
1568                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1569                         ret = -EFAULT;
1570                         goto out;
1571                 }
1572         }
1573
1574         len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET;
1575         vs_tpg = kzalloc(len, GFP_KERNEL);
1576         if (!vs_tpg) {
1577                 ret = -ENOMEM;
1578                 goto out;
1579         }
1580         if (vs->vs_tpg)
1581                 memcpy(vs_tpg, vs->vs_tpg, len);
1582
1583         list_for_each_entry(tpg, &vhost_scsi_list, tv_tpg_list) {
1584                 mutex_lock(&tpg->tv_tpg_mutex);
1585                 if (!tpg->tpg_nexus) {
1586                         mutex_unlock(&tpg->tv_tpg_mutex);
1587                         continue;
1588                 }
1589                 if (tpg->tv_tpg_vhost_count != 0) {
1590                         mutex_unlock(&tpg->tv_tpg_mutex);
1591                         continue;
1592                 }
1593                 tv_tport = tpg->tport;
1594
1595                 if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1596                         if (vs->vs_tpg && vs->vs_tpg[tpg->tport_tpgt]) {
1597                                 mutex_unlock(&tpg->tv_tpg_mutex);
1598                                 ret = -EEXIST;
1599                                 goto undepend;
1600                         }
1601                         /*
1602                          * In order to ensure individual vhost-scsi configfs
1603                          * groups cannot be removed while in use by vhost ioctl,
1604                          * go ahead and take an explicit se_tpg->tpg_group.cg_item
1605                          * dependency now.
1606                          */
1607                         se_tpg = &tpg->se_tpg;
1608                         ret = target_depend_item(&se_tpg->tpg_group.cg_item);
1609                         if (ret) {
1610                                 pr_warn("target_depend_item() failed: %d\n", ret);
1611                                 mutex_unlock(&tpg->tv_tpg_mutex);
1612                                 goto undepend;
1613                         }
1614                         tpg->tv_tpg_vhost_count++;
1615                         tpg->vhost_scsi = vs;
1616                         vs_tpg[tpg->tport_tpgt] = tpg;
1617                         match = true;
1618                 }
1619                 mutex_unlock(&tpg->tv_tpg_mutex);
1620         }
1621
1622         if (match) {
1623                 memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
1624                        sizeof(vs->vs_vhost_wwpn));
1625
1626                 for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++) {
1627                         vq = &vs->vqs[i].vq;
1628                         if (!vhost_vq_is_setup(vq))
1629                                 continue;
1630
1631                         ret = vhost_scsi_setup_vq_cmds(vq, vq->num);
1632                         if (ret)
1633                                 goto destroy_vq_cmds;
1634                 }
1635
1636                 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1637                         vq = &vs->vqs[i].vq;
1638                         mutex_lock(&vq->mutex);
1639                         vhost_vq_set_backend(vq, vs_tpg);
1640                         vhost_vq_init_access(vq);
1641                         mutex_unlock(&vq->mutex);
1642                 }
1643                 ret = 0;
1644         } else {
1645                 ret = -EEXIST;
1646         }
1647
1648         /*
1649          * Act as synchronize_rcu to make sure access to
1650          * old vs->vs_tpg is finished.
1651          */
1652         vhost_scsi_flush(vs);
1653         kfree(vs->vs_tpg);
1654         vs->vs_tpg = vs_tpg;
1655         goto out;
1656
1657 destroy_vq_cmds:
1658         for (i--; i >= VHOST_SCSI_VQ_IO; i--) {
1659                 if (!vhost_vq_get_backend(&vs->vqs[i].vq))
1660                         vhost_scsi_destroy_vq_cmds(&vs->vqs[i].vq);
1661         }
1662 undepend:
1663         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1664                 tpg = vs_tpg[i];
1665                 if (tpg) {
1666                         tpg->tv_tpg_vhost_count--;
1667                         target_undepend_item(&tpg->se_tpg.tpg_group.cg_item);
1668                 }
1669         }
1670         kfree(vs_tpg);
1671 out:
1672         mutex_unlock(&vs->dev.mutex);
1673         mutex_unlock(&vhost_scsi_mutex);
1674         return ret;
1675 }
1676
1677 static int
1678 vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
1679                           struct vhost_scsi_target *t)
1680 {
1681         struct se_portal_group *se_tpg;
1682         struct vhost_scsi_tport *tv_tport;
1683         struct vhost_scsi_tpg *tpg;
1684         struct vhost_virtqueue *vq;
1685         bool match = false;
1686         int index, ret, i;
1687         u8 target;
1688
1689         mutex_lock(&vhost_scsi_mutex);
1690         mutex_lock(&vs->dev.mutex);
1691         /* Verify that ring has been setup correctly. */
1692         for (index = 0; index < vs->dev.nvqs; ++index) {
1693                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1694                         ret = -EFAULT;
1695                         goto err_dev;
1696                 }
1697         }
1698
1699         if (!vs->vs_tpg) {
1700                 ret = 0;
1701                 goto err_dev;
1702         }
1703
1704         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1705                 target = i;
1706                 tpg = vs->vs_tpg[target];
1707                 if (!tpg)
1708                         continue;
1709
1710                 mutex_lock(&tpg->tv_tpg_mutex);
1711                 tv_tport = tpg->tport;
1712                 if (!tv_tport) {
1713                         ret = -ENODEV;
1714                         goto err_tpg;
1715                 }
1716
1717                 if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1718                         pr_warn("tv_tport->tport_name: %s, tpg->tport_tpgt: %hu"
1719                                 " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
1720                                 tv_tport->tport_name, tpg->tport_tpgt,
1721                                 t->vhost_wwpn, t->vhost_tpgt);
1722                         ret = -EINVAL;
1723                         goto err_tpg;
1724                 }
1725                 tpg->tv_tpg_vhost_count--;
1726                 tpg->vhost_scsi = NULL;
1727                 vs->vs_tpg[target] = NULL;
1728                 match = true;
1729                 mutex_unlock(&tpg->tv_tpg_mutex);
1730                 /*
1731                  * Release se_tpg->tpg_group.cg_item configfs dependency now
1732                  * to allow vhost-scsi WWPN se_tpg->tpg_group shutdown to occur.
1733                  */
1734                 se_tpg = &tpg->se_tpg;
1735                 target_undepend_item(&se_tpg->tpg_group.cg_item);
1736         }
1737         if (match) {
1738                 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1739                         vq = &vs->vqs[i].vq;
1740                         mutex_lock(&vq->mutex);
1741                         vhost_vq_set_backend(vq, NULL);
1742                         mutex_unlock(&vq->mutex);
1743                         /*
1744                          * Make sure cmds are not running before tearing them
1745                          * down.
1746                          */
1747                         vhost_scsi_flush(vs);
1748                         vhost_scsi_destroy_vq_cmds(vq);
1749                 }
1750         }
1751         /*
1752          * Act as synchronize_rcu to make sure access to
1753          * old vs->vs_tpg is finished.
1754          */
1755         vhost_scsi_flush(vs);
1756         kfree(vs->vs_tpg);
1757         vs->vs_tpg = NULL;
1758         WARN_ON(vs->vs_events_nr);
1759         mutex_unlock(&vs->dev.mutex);
1760         mutex_unlock(&vhost_scsi_mutex);
1761         return 0;
1762
1763 err_tpg:
1764         mutex_unlock(&tpg->tv_tpg_mutex);
1765 err_dev:
1766         mutex_unlock(&vs->dev.mutex);
1767         mutex_unlock(&vhost_scsi_mutex);
1768         return ret;
1769 }
1770
1771 static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features)
1772 {
1773         struct vhost_virtqueue *vq;
1774         int i;
1775
1776         if (features & ~VHOST_SCSI_FEATURES)
1777                 return -EOPNOTSUPP;
1778
1779         mutex_lock(&vs->dev.mutex);
1780         if ((features & (1 << VHOST_F_LOG_ALL)) &&
1781             !vhost_log_access_ok(&vs->dev)) {
1782                 mutex_unlock(&vs->dev.mutex);
1783                 return -EFAULT;
1784         }
1785
1786         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1787                 vq = &vs->vqs[i].vq;
1788                 mutex_lock(&vq->mutex);
1789                 vq->acked_features = features;
1790                 mutex_unlock(&vq->mutex);
1791         }
1792         mutex_unlock(&vs->dev.mutex);
1793         return 0;
1794 }
1795
1796 static int vhost_scsi_open(struct inode *inode, struct file *f)
1797 {
1798         struct vhost_scsi *vs;
1799         struct vhost_virtqueue **vqs;
1800         int r = -ENOMEM, i;
1801
1802         vs = kvzalloc(sizeof(*vs), GFP_KERNEL);
1803         if (!vs)
1804                 goto err_vs;
1805
1806         vqs = kmalloc_array(VHOST_SCSI_MAX_VQ, sizeof(*vqs), GFP_KERNEL);
1807         if (!vqs)
1808                 goto err_vqs;
1809
1810         vhost_work_init(&vs->vs_completion_work, vhost_scsi_complete_cmd_work);
1811         vhost_work_init(&vs->vs_event_work, vhost_scsi_evt_work);
1812
1813         vs->vs_events_nr = 0;
1814         vs->vs_events_missed = false;
1815
1816         vqs[VHOST_SCSI_VQ_CTL] = &vs->vqs[VHOST_SCSI_VQ_CTL].vq;
1817         vqs[VHOST_SCSI_VQ_EVT] = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1818         vs->vqs[VHOST_SCSI_VQ_CTL].vq.handle_kick = vhost_scsi_ctl_handle_kick;
1819         vs->vqs[VHOST_SCSI_VQ_EVT].vq.handle_kick = vhost_scsi_evt_handle_kick;
1820         for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++) {
1821                 vqs[i] = &vs->vqs[i].vq;
1822                 vs->vqs[i].vq.handle_kick = vhost_scsi_handle_kick;
1823         }
1824         vhost_dev_init(&vs->dev, vqs, VHOST_SCSI_MAX_VQ, UIO_MAXIOV,
1825                        VHOST_SCSI_WEIGHT, 0, true, NULL);
1826
1827         vhost_scsi_init_inflight(vs, NULL);
1828
1829         f->private_data = vs;
1830         return 0;
1831
1832 err_vqs:
1833         kvfree(vs);
1834 err_vs:
1835         return r;
1836 }
1837
1838 static int vhost_scsi_release(struct inode *inode, struct file *f)
1839 {
1840         struct vhost_scsi *vs = f->private_data;
1841         struct vhost_scsi_target t;
1842
1843         mutex_lock(&vs->dev.mutex);
1844         memcpy(t.vhost_wwpn, vs->vs_vhost_wwpn, sizeof(t.vhost_wwpn));
1845         mutex_unlock(&vs->dev.mutex);
1846         vhost_scsi_clear_endpoint(vs, &t);
1847         vhost_dev_stop(&vs->dev);
1848         vhost_dev_cleanup(&vs->dev);
1849         /* Jobs can re-queue themselves in evt kick handler. Do extra flush. */
1850         vhost_scsi_flush(vs);
1851         kfree(vs->dev.vqs);
1852         kvfree(vs);
1853         return 0;
1854 }
1855
1856 static long
1857 vhost_scsi_ioctl(struct file *f,
1858                  unsigned int ioctl,
1859                  unsigned long arg)
1860 {
1861         struct vhost_scsi *vs = f->private_data;
1862         struct vhost_scsi_target backend;
1863         void __user *argp = (void __user *)arg;
1864         u64 __user *featurep = argp;
1865         u32 __user *eventsp = argp;
1866         u32 events_missed;
1867         u64 features;
1868         int r, abi_version = VHOST_SCSI_ABI_VERSION;
1869         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1870
1871         switch (ioctl) {
1872         case VHOST_SCSI_SET_ENDPOINT:
1873                 if (copy_from_user(&backend, argp, sizeof backend))
1874                         return -EFAULT;
1875                 if (backend.reserved != 0)
1876                         return -EOPNOTSUPP;
1877
1878                 return vhost_scsi_set_endpoint(vs, &backend);
1879         case VHOST_SCSI_CLEAR_ENDPOINT:
1880                 if (copy_from_user(&backend, argp, sizeof backend))
1881                         return -EFAULT;
1882                 if (backend.reserved != 0)
1883                         return -EOPNOTSUPP;
1884
1885                 return vhost_scsi_clear_endpoint(vs, &backend);
1886         case VHOST_SCSI_GET_ABI_VERSION:
1887                 if (copy_to_user(argp, &abi_version, sizeof abi_version))
1888                         return -EFAULT;
1889                 return 0;
1890         case VHOST_SCSI_SET_EVENTS_MISSED:
1891                 if (get_user(events_missed, eventsp))
1892                         return -EFAULT;
1893                 mutex_lock(&vq->mutex);
1894                 vs->vs_events_missed = events_missed;
1895                 mutex_unlock(&vq->mutex);
1896                 return 0;
1897         case VHOST_SCSI_GET_EVENTS_MISSED:
1898                 mutex_lock(&vq->mutex);
1899                 events_missed = vs->vs_events_missed;
1900                 mutex_unlock(&vq->mutex);
1901                 if (put_user(events_missed, eventsp))
1902                         return -EFAULT;
1903                 return 0;
1904         case VHOST_GET_FEATURES:
1905                 features = VHOST_SCSI_FEATURES;
1906                 if (copy_to_user(featurep, &features, sizeof features))
1907                         return -EFAULT;
1908                 return 0;
1909         case VHOST_SET_FEATURES:
1910                 if (copy_from_user(&features, featurep, sizeof features))
1911                         return -EFAULT;
1912                 return vhost_scsi_set_features(vs, features);
1913         default:
1914                 mutex_lock(&vs->dev.mutex);
1915                 r = vhost_dev_ioctl(&vs->dev, ioctl, argp);
1916                 /* TODO: flush backend after dev ioctl. */
1917                 if (r == -ENOIOCTLCMD)
1918                         r = vhost_vring_ioctl(&vs->dev, ioctl, argp);
1919                 mutex_unlock(&vs->dev.mutex);
1920                 return r;
1921         }
1922 }
1923
1924 static const struct file_operations vhost_scsi_fops = {
1925         .owner          = THIS_MODULE,
1926         .release        = vhost_scsi_release,
1927         .unlocked_ioctl = vhost_scsi_ioctl,
1928         .compat_ioctl   = compat_ptr_ioctl,
1929         .open           = vhost_scsi_open,
1930         .llseek         = noop_llseek,
1931 };
1932
1933 static struct miscdevice vhost_scsi_misc = {
1934         MISC_DYNAMIC_MINOR,
1935         "vhost-scsi",
1936         &vhost_scsi_fops,
1937 };
1938
1939 static int __init vhost_scsi_register(void)
1940 {
1941         return misc_register(&vhost_scsi_misc);
1942 }
1943
1944 static void vhost_scsi_deregister(void)
1945 {
1946         misc_deregister(&vhost_scsi_misc);
1947 }
1948
1949 static char *vhost_scsi_dump_proto_id(struct vhost_scsi_tport *tport)
1950 {
1951         switch (tport->tport_proto_id) {
1952         case SCSI_PROTOCOL_SAS:
1953                 return "SAS";
1954         case SCSI_PROTOCOL_FCP:
1955                 return "FCP";
1956         case SCSI_PROTOCOL_ISCSI:
1957                 return "iSCSI";
1958         default:
1959                 break;
1960         }
1961
1962         return "Unknown";
1963 }
1964
1965 static void
1966 vhost_scsi_do_plug(struct vhost_scsi_tpg *tpg,
1967                   struct se_lun *lun, bool plug)
1968 {
1969
1970         struct vhost_scsi *vs = tpg->vhost_scsi;
1971         struct vhost_virtqueue *vq;
1972         u32 reason;
1973
1974         if (!vs)
1975                 return;
1976
1977         mutex_lock(&vs->dev.mutex);
1978
1979         if (plug)
1980                 reason = VIRTIO_SCSI_EVT_RESET_RESCAN;
1981         else
1982                 reason = VIRTIO_SCSI_EVT_RESET_REMOVED;
1983
1984         vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1985         mutex_lock(&vq->mutex);
1986         if (vhost_has_feature(vq, VIRTIO_SCSI_F_HOTPLUG))
1987                 vhost_scsi_send_evt(vs, tpg, lun,
1988                                    VIRTIO_SCSI_T_TRANSPORT_RESET, reason);
1989         mutex_unlock(&vq->mutex);
1990         mutex_unlock(&vs->dev.mutex);
1991 }
1992
1993 static void vhost_scsi_hotplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
1994 {
1995         vhost_scsi_do_plug(tpg, lun, true);
1996 }
1997
1998 static void vhost_scsi_hotunplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
1999 {
2000         vhost_scsi_do_plug(tpg, lun, false);
2001 }
2002
2003 static int vhost_scsi_port_link(struct se_portal_group *se_tpg,
2004                                struct se_lun *lun)
2005 {
2006         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2007                                 struct vhost_scsi_tpg, se_tpg);
2008         struct vhost_scsi_tmf *tmf;
2009
2010         tmf = kzalloc(sizeof(*tmf), GFP_KERNEL);
2011         if (!tmf)
2012                 return -ENOMEM;
2013         INIT_LIST_HEAD(&tmf->queue_entry);
2014         vhost_work_init(&tmf->vwork, vhost_scsi_tmf_resp_work);
2015
2016         mutex_lock(&vhost_scsi_mutex);
2017
2018         mutex_lock(&tpg->tv_tpg_mutex);
2019         tpg->tv_tpg_port_count++;
2020         list_add_tail(&tmf->queue_entry, &tpg->tmf_queue);
2021         mutex_unlock(&tpg->tv_tpg_mutex);
2022
2023         vhost_scsi_hotplug(tpg, lun);
2024
2025         mutex_unlock(&vhost_scsi_mutex);
2026
2027         return 0;
2028 }
2029
2030 static void vhost_scsi_port_unlink(struct se_portal_group *se_tpg,
2031                                   struct se_lun *lun)
2032 {
2033         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2034                                 struct vhost_scsi_tpg, se_tpg);
2035         struct vhost_scsi_tmf *tmf;
2036
2037         mutex_lock(&vhost_scsi_mutex);
2038
2039         mutex_lock(&tpg->tv_tpg_mutex);
2040         tpg->tv_tpg_port_count--;
2041         tmf = list_first_entry(&tpg->tmf_queue, struct vhost_scsi_tmf,
2042                                queue_entry);
2043         list_del(&tmf->queue_entry);
2044         kfree(tmf);
2045         mutex_unlock(&tpg->tv_tpg_mutex);
2046
2047         vhost_scsi_hotunplug(tpg, lun);
2048
2049         mutex_unlock(&vhost_scsi_mutex);
2050 }
2051
2052 static ssize_t vhost_scsi_tpg_attrib_fabric_prot_type_store(
2053                 struct config_item *item, const char *page, size_t count)
2054 {
2055         struct se_portal_group *se_tpg = attrib_to_tpg(item);
2056         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2057                                 struct vhost_scsi_tpg, se_tpg);
2058         unsigned long val;
2059         int ret = kstrtoul(page, 0, &val);
2060
2061         if (ret) {
2062                 pr_err("kstrtoul() returned %d for fabric_prot_type\n", ret);
2063                 return ret;
2064         }
2065         if (val != 0 && val != 1 && val != 3) {
2066                 pr_err("Invalid vhost_scsi fabric_prot_type: %lu\n", val);
2067                 return -EINVAL;
2068         }
2069         tpg->tv_fabric_prot_type = val;
2070
2071         return count;
2072 }
2073
2074 static ssize_t vhost_scsi_tpg_attrib_fabric_prot_type_show(
2075                 struct config_item *item, char *page)
2076 {
2077         struct se_portal_group *se_tpg = attrib_to_tpg(item);
2078         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2079                                 struct vhost_scsi_tpg, se_tpg);
2080
2081         return sprintf(page, "%d\n", tpg->tv_fabric_prot_type);
2082 }
2083
2084 CONFIGFS_ATTR(vhost_scsi_tpg_attrib_, fabric_prot_type);
2085
2086 static struct configfs_attribute *vhost_scsi_tpg_attrib_attrs[] = {
2087         &vhost_scsi_tpg_attrib_attr_fabric_prot_type,
2088         NULL,
2089 };
2090
2091 static int vhost_scsi_make_nexus(struct vhost_scsi_tpg *tpg,
2092                                 const char *name)
2093 {
2094         struct vhost_scsi_nexus *tv_nexus;
2095
2096         mutex_lock(&tpg->tv_tpg_mutex);
2097         if (tpg->tpg_nexus) {
2098                 mutex_unlock(&tpg->tv_tpg_mutex);
2099                 pr_debug("tpg->tpg_nexus already exists\n");
2100                 return -EEXIST;
2101         }
2102
2103         tv_nexus = kzalloc(sizeof(*tv_nexus), GFP_KERNEL);
2104         if (!tv_nexus) {
2105                 mutex_unlock(&tpg->tv_tpg_mutex);
2106                 pr_err("Unable to allocate struct vhost_scsi_nexus\n");
2107                 return -ENOMEM;
2108         }
2109         /*
2110          * Since we are running in 'demo mode' this call with generate a
2111          * struct se_node_acl for the vhost_scsi struct se_portal_group with
2112          * the SCSI Initiator port name of the passed configfs group 'name'.
2113          */
2114         tv_nexus->tvn_se_sess = target_setup_session(&tpg->se_tpg, 0, 0,
2115                                         TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS,
2116                                         (unsigned char *)name, tv_nexus, NULL);
2117         if (IS_ERR(tv_nexus->tvn_se_sess)) {
2118                 mutex_unlock(&tpg->tv_tpg_mutex);
2119                 kfree(tv_nexus);
2120                 return -ENOMEM;
2121         }
2122         tpg->tpg_nexus = tv_nexus;
2123
2124         mutex_unlock(&tpg->tv_tpg_mutex);
2125         return 0;
2126 }
2127
2128 static int vhost_scsi_drop_nexus(struct vhost_scsi_tpg *tpg)
2129 {
2130         struct se_session *se_sess;
2131         struct vhost_scsi_nexus *tv_nexus;
2132
2133         mutex_lock(&tpg->tv_tpg_mutex);
2134         tv_nexus = tpg->tpg_nexus;
2135         if (!tv_nexus) {
2136                 mutex_unlock(&tpg->tv_tpg_mutex);
2137                 return -ENODEV;
2138         }
2139
2140         se_sess = tv_nexus->tvn_se_sess;
2141         if (!se_sess) {
2142                 mutex_unlock(&tpg->tv_tpg_mutex);
2143                 return -ENODEV;
2144         }
2145
2146         if (tpg->tv_tpg_port_count != 0) {
2147                 mutex_unlock(&tpg->tv_tpg_mutex);
2148                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
2149                         " active TPG port count: %d\n",
2150                         tpg->tv_tpg_port_count);
2151                 return -EBUSY;
2152         }
2153
2154         if (tpg->tv_tpg_vhost_count != 0) {
2155                 mutex_unlock(&tpg->tv_tpg_mutex);
2156                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
2157                         " active TPG vhost count: %d\n",
2158                         tpg->tv_tpg_vhost_count);
2159                 return -EBUSY;
2160         }
2161
2162         pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated"
2163                 " %s Initiator Port: %s\n", vhost_scsi_dump_proto_id(tpg->tport),
2164                 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
2165
2166         /*
2167          * Release the SCSI I_T Nexus to the emulated vhost Target Port
2168          */
2169         target_remove_session(se_sess);
2170         tpg->tpg_nexus = NULL;
2171         mutex_unlock(&tpg->tv_tpg_mutex);
2172
2173         kfree(tv_nexus);
2174         return 0;
2175 }
2176
2177 static ssize_t vhost_scsi_tpg_nexus_show(struct config_item *item, char *page)
2178 {
2179         struct se_portal_group *se_tpg = to_tpg(item);
2180         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2181                                 struct vhost_scsi_tpg, se_tpg);
2182         struct vhost_scsi_nexus *tv_nexus;
2183         ssize_t ret;
2184
2185         mutex_lock(&tpg->tv_tpg_mutex);
2186         tv_nexus = tpg->tpg_nexus;
2187         if (!tv_nexus) {
2188                 mutex_unlock(&tpg->tv_tpg_mutex);
2189                 return -ENODEV;
2190         }
2191         ret = snprintf(page, PAGE_SIZE, "%s\n",
2192                         tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
2193         mutex_unlock(&tpg->tv_tpg_mutex);
2194
2195         return ret;
2196 }
2197
2198 static ssize_t vhost_scsi_tpg_nexus_store(struct config_item *item,
2199                 const char *page, size_t count)
2200 {
2201         struct se_portal_group *se_tpg = to_tpg(item);
2202         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2203                                 struct vhost_scsi_tpg, se_tpg);
2204         struct vhost_scsi_tport *tport_wwn = tpg->tport;
2205         unsigned char i_port[VHOST_SCSI_NAMELEN], *ptr, *port_ptr;
2206         int ret;
2207         /*
2208          * Shutdown the active I_T nexus if 'NULL' is passed..
2209          */
2210         if (!strncmp(page, "NULL", 4)) {
2211                 ret = vhost_scsi_drop_nexus(tpg);
2212                 return (!ret) ? count : ret;
2213         }
2214         /*
2215          * Otherwise make sure the passed virtual Initiator port WWN matches
2216          * the fabric protocol_id set in vhost_scsi_make_tport(), and call
2217          * vhost_scsi_make_nexus().
2218          */
2219         if (strlen(page) >= VHOST_SCSI_NAMELEN) {
2220                 pr_err("Emulated NAA Sas Address: %s, exceeds"
2221                                 " max: %d\n", page, VHOST_SCSI_NAMELEN);
2222                 return -EINVAL;
2223         }
2224         snprintf(&i_port[0], VHOST_SCSI_NAMELEN, "%s", page);
2225
2226         ptr = strstr(i_port, "naa.");
2227         if (ptr) {
2228                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
2229                         pr_err("Passed SAS Initiator Port %s does not"
2230                                 " match target port protoid: %s\n", i_port,
2231                                 vhost_scsi_dump_proto_id(tport_wwn));
2232                         return -EINVAL;
2233                 }
2234                 port_ptr = &i_port[0];
2235                 goto check_newline;
2236         }
2237         ptr = strstr(i_port, "fc.");
2238         if (ptr) {
2239                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
2240                         pr_err("Passed FCP Initiator Port %s does not"
2241                                 " match target port protoid: %s\n", i_port,
2242                                 vhost_scsi_dump_proto_id(tport_wwn));
2243                         return -EINVAL;
2244                 }
2245                 port_ptr = &i_port[3]; /* Skip over "fc." */
2246                 goto check_newline;
2247         }
2248         ptr = strstr(i_port, "iqn.");
2249         if (ptr) {
2250                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
2251                         pr_err("Passed iSCSI Initiator Port %s does not"
2252                                 " match target port protoid: %s\n", i_port,
2253                                 vhost_scsi_dump_proto_id(tport_wwn));
2254                         return -EINVAL;
2255                 }
2256                 port_ptr = &i_port[0];
2257                 goto check_newline;
2258         }
2259         pr_err("Unable to locate prefix for emulated Initiator Port:"
2260                         " %s\n", i_port);
2261         return -EINVAL;
2262         /*
2263          * Clear any trailing newline for the NAA WWN
2264          */
2265 check_newline:
2266         if (i_port[strlen(i_port)-1] == '\n')
2267                 i_port[strlen(i_port)-1] = '\0';
2268
2269         ret = vhost_scsi_make_nexus(tpg, port_ptr);
2270         if (ret < 0)
2271                 return ret;
2272
2273         return count;
2274 }
2275
2276 CONFIGFS_ATTR(vhost_scsi_tpg_, nexus);
2277
2278 static struct configfs_attribute *vhost_scsi_tpg_attrs[] = {
2279         &vhost_scsi_tpg_attr_nexus,
2280         NULL,
2281 };
2282
2283 static struct se_portal_group *
2284 vhost_scsi_make_tpg(struct se_wwn *wwn, const char *name)
2285 {
2286         struct vhost_scsi_tport *tport = container_of(wwn,
2287                         struct vhost_scsi_tport, tport_wwn);
2288
2289         struct vhost_scsi_tpg *tpg;
2290         u16 tpgt;
2291         int ret;
2292
2293         if (strstr(name, "tpgt_") != name)
2294                 return ERR_PTR(-EINVAL);
2295         if (kstrtou16(name + 5, 10, &tpgt) || tpgt >= VHOST_SCSI_MAX_TARGET)
2296                 return ERR_PTR(-EINVAL);
2297
2298         tpg = kzalloc(sizeof(*tpg), GFP_KERNEL);
2299         if (!tpg) {
2300                 pr_err("Unable to allocate struct vhost_scsi_tpg");
2301                 return ERR_PTR(-ENOMEM);
2302         }
2303         mutex_init(&tpg->tv_tpg_mutex);
2304         INIT_LIST_HEAD(&tpg->tv_tpg_list);
2305         INIT_LIST_HEAD(&tpg->tmf_queue);
2306         tpg->tport = tport;
2307         tpg->tport_tpgt = tpgt;
2308
2309         ret = core_tpg_register(wwn, &tpg->se_tpg, tport->tport_proto_id);
2310         if (ret < 0) {
2311                 kfree(tpg);
2312                 return NULL;
2313         }
2314         mutex_lock(&vhost_scsi_mutex);
2315         list_add_tail(&tpg->tv_tpg_list, &vhost_scsi_list);
2316         mutex_unlock(&vhost_scsi_mutex);
2317
2318         return &tpg->se_tpg;
2319 }
2320
2321 static void vhost_scsi_drop_tpg(struct se_portal_group *se_tpg)
2322 {
2323         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2324                                 struct vhost_scsi_tpg, se_tpg);
2325
2326         mutex_lock(&vhost_scsi_mutex);
2327         list_del(&tpg->tv_tpg_list);
2328         mutex_unlock(&vhost_scsi_mutex);
2329         /*
2330          * Release the virtual I_T Nexus for this vhost TPG
2331          */
2332         vhost_scsi_drop_nexus(tpg);
2333         /*
2334          * Deregister the se_tpg from TCM..
2335          */
2336         core_tpg_deregister(se_tpg);
2337         kfree(tpg);
2338 }
2339
2340 static struct se_wwn *
2341 vhost_scsi_make_tport(struct target_fabric_configfs *tf,
2342                      struct config_group *group,
2343                      const char *name)
2344 {
2345         struct vhost_scsi_tport *tport;
2346         char *ptr;
2347         u64 wwpn = 0;
2348         int off = 0;
2349
2350         /* if (vhost_scsi_parse_wwn(name, &wwpn, 1) < 0)
2351                 return ERR_PTR(-EINVAL); */
2352
2353         tport = kzalloc(sizeof(*tport), GFP_KERNEL);
2354         if (!tport) {
2355                 pr_err("Unable to allocate struct vhost_scsi_tport");
2356                 return ERR_PTR(-ENOMEM);
2357         }
2358         tport->tport_wwpn = wwpn;
2359         /*
2360          * Determine the emulated Protocol Identifier and Target Port Name
2361          * based on the incoming configfs directory name.
2362          */
2363         ptr = strstr(name, "naa.");
2364         if (ptr) {
2365                 tport->tport_proto_id = SCSI_PROTOCOL_SAS;
2366                 goto check_len;
2367         }
2368         ptr = strstr(name, "fc.");
2369         if (ptr) {
2370                 tport->tport_proto_id = SCSI_PROTOCOL_FCP;
2371                 off = 3; /* Skip over "fc." */
2372                 goto check_len;
2373         }
2374         ptr = strstr(name, "iqn.");
2375         if (ptr) {
2376                 tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
2377                 goto check_len;
2378         }
2379
2380         pr_err("Unable to locate prefix for emulated Target Port:"
2381                         " %s\n", name);
2382         kfree(tport);
2383         return ERR_PTR(-EINVAL);
2384
2385 check_len:
2386         if (strlen(name) >= VHOST_SCSI_NAMELEN) {
2387                 pr_err("Emulated %s Address: %s, exceeds"
2388                         " max: %d\n", name, vhost_scsi_dump_proto_id(tport),
2389                         VHOST_SCSI_NAMELEN);
2390                 kfree(tport);
2391                 return ERR_PTR(-EINVAL);
2392         }
2393         snprintf(&tport->tport_name[0], VHOST_SCSI_NAMELEN, "%s", &name[off]);
2394
2395         pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target"
2396                 " %s Address: %s\n", vhost_scsi_dump_proto_id(tport), name);
2397
2398         return &tport->tport_wwn;
2399 }
2400
2401 static void vhost_scsi_drop_tport(struct se_wwn *wwn)
2402 {
2403         struct vhost_scsi_tport *tport = container_of(wwn,
2404                                 struct vhost_scsi_tport, tport_wwn);
2405
2406         pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target"
2407                 " %s Address: %s\n", vhost_scsi_dump_proto_id(tport),
2408                 tport->tport_name);
2409
2410         kfree(tport);
2411 }
2412
2413 static ssize_t
2414 vhost_scsi_wwn_version_show(struct config_item *item, char *page)
2415 {
2416         return sprintf(page, "TCM_VHOST fabric module %s on %s/%s"
2417                 "on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
2418                 utsname()->machine);
2419 }
2420
2421 CONFIGFS_ATTR_RO(vhost_scsi_wwn_, version);
2422
2423 static struct configfs_attribute *vhost_scsi_wwn_attrs[] = {
2424         &vhost_scsi_wwn_attr_version,
2425         NULL,
2426 };
2427
2428 static const struct target_core_fabric_ops vhost_scsi_ops = {
2429         .module                         = THIS_MODULE,
2430         .fabric_name                    = "vhost",
2431         .max_data_sg_nents              = VHOST_SCSI_PREALLOC_SGLS,
2432         .tpg_get_wwn                    = vhost_scsi_get_fabric_wwn,
2433         .tpg_get_tag                    = vhost_scsi_get_tpgt,
2434         .tpg_check_demo_mode            = vhost_scsi_check_true,
2435         .tpg_check_demo_mode_cache      = vhost_scsi_check_true,
2436         .tpg_check_demo_mode_write_protect = vhost_scsi_check_false,
2437         .tpg_check_prod_mode_write_protect = vhost_scsi_check_false,
2438         .tpg_check_prot_fabric_only     = vhost_scsi_check_prot_fabric_only,
2439         .tpg_get_inst_index             = vhost_scsi_tpg_get_inst_index,
2440         .release_cmd                    = vhost_scsi_release_cmd,
2441         .check_stop_free                = vhost_scsi_check_stop_free,
2442         .sess_get_index                 = vhost_scsi_sess_get_index,
2443         .sess_get_initiator_sid         = NULL,
2444         .write_pending                  = vhost_scsi_write_pending,
2445         .set_default_node_attributes    = vhost_scsi_set_default_node_attrs,
2446         .get_cmd_state                  = vhost_scsi_get_cmd_state,
2447         .queue_data_in                  = vhost_scsi_queue_data_in,
2448         .queue_status                   = vhost_scsi_queue_status,
2449         .queue_tm_rsp                   = vhost_scsi_queue_tm_rsp,
2450         .aborted_task                   = vhost_scsi_aborted_task,
2451         /*
2452          * Setup callers for generic logic in target_core_fabric_configfs.c
2453          */
2454         .fabric_make_wwn                = vhost_scsi_make_tport,
2455         .fabric_drop_wwn                = vhost_scsi_drop_tport,
2456         .fabric_make_tpg                = vhost_scsi_make_tpg,
2457         .fabric_drop_tpg                = vhost_scsi_drop_tpg,
2458         .fabric_post_link               = vhost_scsi_port_link,
2459         .fabric_pre_unlink              = vhost_scsi_port_unlink,
2460
2461         .tfc_wwn_attrs                  = vhost_scsi_wwn_attrs,
2462         .tfc_tpg_base_attrs             = vhost_scsi_tpg_attrs,
2463         .tfc_tpg_attrib_attrs           = vhost_scsi_tpg_attrib_attrs,
2464 };
2465
2466 static int __init vhost_scsi_init(void)
2467 {
2468         int ret = -ENOMEM;
2469
2470         pr_debug("TCM_VHOST fabric module %s on %s/%s"
2471                 " on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
2472                 utsname()->machine);
2473
2474         ret = vhost_scsi_register();
2475         if (ret < 0)
2476                 goto out;
2477
2478         ret = target_register_template(&vhost_scsi_ops);
2479         if (ret < 0)
2480                 goto out_vhost_scsi_deregister;
2481
2482         return 0;
2483
2484 out_vhost_scsi_deregister:
2485         vhost_scsi_deregister();
2486 out:
2487         return ret;
2488 };
2489
2490 static void vhost_scsi_exit(void)
2491 {
2492         target_unregister_template(&vhost_scsi_ops);
2493         vhost_scsi_deregister();
2494 };
2495
2496 MODULE_DESCRIPTION("VHOST_SCSI series fabric driver");
2497 MODULE_ALIAS("tcm_vhost");
2498 MODULE_LICENSE("GPL");
2499 module_init(vhost_scsi_init);
2500 module_exit(vhost_scsi_exit);