drivers/vhost/scsi.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*******************************************************************************
   3  * Vhost kernel TCM fabric driver for virtio SCSI initiators
   4  *
   5  * (C) Copyright 2010-2013 Datera, Inc.
   6  * (C) Copyright 2010-2012 IBM Corp.
   7  *
   8  * Authors: Nicholas A. Bellinger <nab@daterainc.com>
   9  *          Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
  10  ****************************************************************************/
  11
  12 #include <linux/module.h>
  13 #include <linux/moduleparam.h>
  14 #include <generated/utsrelease.h>
  15 #include <linux/utsname.h>
  16 #include <linux/init.h>
  17 #include <linux/slab.h>
  18 #include <linux/kthread.h>
  19 #include <linux/types.h>
  20 #include <linux/string.h>
  21 #include <linux/configfs.h>
  22 #include <linux/ctype.h>
  23 #include <linux/compat.h>
  24 #include <linux/eventfd.h>
  25 #include <linux/fs.h>
  26 #include <linux/vmalloc.h>
  27 #include <linux/miscdevice.h>
  28 #include <asm/unaligned.h>
  29 #include <scsi/scsi_common.h>
  30 #include <scsi/scsi_proto.h>
  31 #include <target/target_core_base.h>
  32 #include <target/target_core_fabric.h>
  33 #include <linux/vhost.h>
  34 #include <linux/virtio_scsi.h>
  35 #include <linux/llist.h>
  36 #include <linux/bitmap.h>
  37
  38 #include "vhost.h"
  39
  40 #define VHOST_SCSI_VERSION  "v0.1"
  41 #define VHOST_SCSI_NAMELEN 256
  42 #define VHOST_SCSI_MAX_CDB_SIZE 32
  43 #define VHOST_SCSI_PREALLOC_SGLS 2048
  44 #define VHOST_SCSI_PREALLOC_UPAGES 2048
  45 #define VHOST_SCSI_PREALLOC_PROT_SGLS 2048
  46
  47 /* Max number of requests before requeueing the job.
  48  * Using this limit prevents one virtqueue from starving others with
  49  * request.
  50  */
  51 #define VHOST_SCSI_WEIGHT 256
  52
  53 struct vhost_scsi_inflight {
  54         /* Wait for the flush operation to finish */
  55         struct completion comp;
  56         /* Refcount for the inflight reqs */
  57         struct kref kref;
  58 };
  59
  60 struct vhost_scsi_cmd {
  61         /* Descriptor from vhost_get_vq_desc() for virt_queue segment */
  62         int tvc_vq_desc;
  63         /* virtio-scsi initiator task attribute */
  64         int tvc_task_attr;
  65         /* virtio-scsi response incoming iovecs */
  66         int tvc_in_iovs;
  67         /* virtio-scsi initiator data direction */
  68         enum dma_data_direction tvc_data_direction;
  69         /* Expected data transfer length from virtio-scsi header */
  70         u32 tvc_exp_data_len;
  71         /* The Tag from include/linux/virtio_scsi.h:struct virtio_scsi_cmd_req */
  72         u64 tvc_tag;
  73         /* The number of scatterlists associated with this cmd */
  74         u32 tvc_sgl_count;
  75         u32 tvc_prot_sgl_count;
  76         /* Saved unpacked SCSI LUN for vhost_scsi_target_queue_cmd() */
  77         u32 tvc_lun;
  78         /* Pointer to the SGL formatted memory from virtio-scsi */
  79         struct scatterlist *tvc_sgl;
  80         struct scatterlist *tvc_prot_sgl;
  81         struct page **tvc_upages;
  82         /* Pointer to response header iovec */
  83         struct iovec tvc_resp_iov;
  84         /* Pointer to vhost_scsi for our device */
  85         struct vhost_scsi *tvc_vhost;
  86         /* Pointer to vhost_virtqueue for the cmd */
  87         struct vhost_virtqueue *tvc_vq;
  88         /* Pointer to vhost nexus memory */
  89         struct vhost_scsi_nexus *tvc_nexus;
  90         /* The TCM I/O descriptor that is accessed via container_of() */
  91         struct se_cmd tvc_se_cmd;
  92         /* Copy of the incoming SCSI command descriptor block (CDB) */
  93         unsigned char tvc_cdb[VHOST_SCSI_MAX_CDB_SIZE];
  94         /* Sense buffer that will be mapped into outgoing status */
  95         unsigned char tvc_sense_buf[TRANSPORT_SENSE_BUFFER];
  96         /* Completed commands list, serviced from vhost worker thread */
  97         struct llist_node tvc_completion_list;
  98         /* Used to track inflight cmd */
  99         struct vhost_scsi_inflight *inflight;
 100 };
 101
 102 struct vhost_scsi_nexus {
 103         /* Pointer to TCM session for I_T Nexus */
 104         struct se_session *tvn_se_sess;
 105 };
 106
 107 struct vhost_scsi_tpg {
 108         /* Vhost port target portal group tag for TCM */
 109         u16 tport_tpgt;
 110         /* Used to track number of TPG Port/Lun Links wrt to explict I_T Nexus shutdown */
 111         int tv_tpg_port_count;
 112         /* Used for vhost_scsi device reference to tpg_nexus, protected by tv_tpg_mutex */
 113         int tv_tpg_vhost_count;
 114         /* Used for enabling T10-PI with legacy devices */
 115         int tv_fabric_prot_type;
 116         /* list for vhost_scsi_list */
 117         struct list_head tv_tpg_list;
 118         /* Used to protect access for tpg_nexus */
 119         struct mutex tv_tpg_mutex;
 120         /* Pointer to the TCM VHost I_T Nexus for this TPG endpoint */
 121         struct vhost_scsi_nexus *tpg_nexus;
 122         /* Pointer back to vhost_scsi_tport */
 123         struct vhost_scsi_tport *tport;
 124         /* Returned by vhost_scsi_make_tpg() */
 125         struct se_portal_group se_tpg;
 126         /* Pointer back to vhost_scsi, protected by tv_tpg_mutex */
 127         struct vhost_scsi *vhost_scsi;
 128         struct list_head tmf_queue;
 129 };
 130
 131 struct vhost_scsi_tport {
 132         /* SCSI protocol the tport is providing */
 133         u8 tport_proto_id;
 134         /* Binary World Wide unique Port Name for Vhost Target port */
 135         u64 tport_wwpn;
 136         /* ASCII formatted WWPN for Vhost Target port */
 137         char tport_name[VHOST_SCSI_NAMELEN];
 138         /* Returned by vhost_scsi_make_tport() */
 139         struct se_wwn tport_wwn;
 140 };
 141
 142 struct vhost_scsi_evt {
 143         /* event to be sent to guest */
 144         struct virtio_scsi_event event;
 145         /* event list, serviced from vhost worker thread */
 146         struct llist_node list;
 147 };
 148
 149 enum {
 150         VHOST_SCSI_VQ_CTL = 0,
 151         VHOST_SCSI_VQ_EVT = 1,
 152         VHOST_SCSI_VQ_IO = 2,
 153 };
 154
 155 /* Note: can't set VIRTIO_F_VERSION_1 yet, since that implies ANY_LAYOUT. */
 156 enum {
 157         VHOST_SCSI_FEATURES = VHOST_FEATURES | (1ULL << VIRTIO_SCSI_F_HOTPLUG) |
 158                                                (1ULL << VIRTIO_SCSI_F_T10_PI)
 159 };
 160
 161 #define VHOST_SCSI_MAX_TARGET   256
 162 #define VHOST_SCSI_MAX_VQ       128
 163 #define VHOST_SCSI_MAX_EVENT    128
 164
 165 struct vhost_scsi_virtqueue {
 166         struct vhost_virtqueue vq;
 167         /*
 168          * Reference counting for inflight reqs, used for flush operation. At
 169          * each time, one reference tracks new commands submitted, while we
 170          * wait for another one to reach 0.
 171          */
 172         struct vhost_scsi_inflight inflights[2];
 173         /*
 174          * Indicate current inflight in use, protected by vq->mutex.
 175          * Writers must also take dev mutex and flush under it.
 176          */
 177         int inflight_idx;
 178         struct vhost_scsi_cmd *scsi_cmds;
 179         struct sbitmap scsi_tags;
 180         int max_cmds;
 181 };
 182
 183 struct vhost_scsi {
 184         /* Protected by vhost_scsi->dev.mutex */
 185         struct vhost_scsi_tpg **vs_tpg;
 186         char vs_vhost_wwpn[TRANSPORT_IQN_LEN];
 187
 188         struct vhost_dev dev;
 189         struct vhost_scsi_virtqueue vqs[VHOST_SCSI_MAX_VQ];
 190
 191         struct vhost_work vs_completion_work; /* cmd completion work item */
 192         struct llist_head vs_completion_list; /* cmd completion queue */
 193
 194         struct vhost_work vs_event_work; /* evt injection work item */
 195         struct llist_head vs_event_list; /* evt injection queue */
 196
 197         bool vs_events_missed; /* any missed events, protected by vq->mutex */
 198         int vs_events_nr; /* num of pending events, protected by vq->mutex */
 199 };
 200
 201 struct vhost_scsi_tmf {
 202         struct vhost_work vwork;
 203         struct vhost_scsi_tpg *tpg;
 204         struct vhost_scsi *vhost;
 205         struct vhost_scsi_virtqueue *svq;
 206         struct list_head queue_entry;
 207
 208         struct se_cmd se_cmd;
 209         u8 scsi_resp;
 210         struct vhost_scsi_inflight *inflight;
 211         struct iovec resp_iov;
 212         int in_iovs;
 213         int vq_desc;
 214 };
 215
 216 /*
 217  * Context for processing request and control queue operations.
 218  */
 219 struct vhost_scsi_ctx {
 220         int head;
 221         unsigned int out, in;
 222         size_t req_size, rsp_size;
 223         size_t out_size, in_size;
 224         u8 *target, *lunp;
 225         void *req;
 226         struct iov_iter out_iter;
 227 };
 228
 229 /* Global spinlock to protect vhost_scsi TPG list for vhost IOCTL access */
 230 static DEFINE_MUTEX(vhost_scsi_mutex);
 231 static LIST_HEAD(vhost_scsi_list);
 232
 233 static void vhost_scsi_done_inflight(struct kref *kref)
 234 {
 235         struct vhost_scsi_inflight *inflight;
 236
 237         inflight = container_of(kref, struct vhost_scsi_inflight, kref);
 238         complete(&inflight->comp);
 239 }
 240
 241 static void vhost_scsi_init_inflight(struct vhost_scsi *vs,
 242                                     struct vhost_scsi_inflight *old_inflight[])
 243 {
 244         struct vhost_scsi_inflight *new_inflight;
 245         struct vhost_virtqueue *vq;
 246         int idx, i;
 247
 248         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
 249                 vq = &vs->vqs[i].vq;
 250
 251                 mutex_lock(&vq->mutex);
 252
 253                 /* store old infight */
 254                 idx = vs->vqs[i].inflight_idx;
 255                 if (old_inflight)
 256                         old_inflight[i] = &vs->vqs[i].inflights[idx];
 257
 258                 /* setup new infight */
 259                 vs->vqs[i].inflight_idx = idx ^ 1;
 260                 new_inflight = &vs->vqs[i].inflights[idx ^ 1];
 261                 kref_init(&new_inflight->kref);
 262                 init_completion(&new_inflight->comp);
 263
 264                 mutex_unlock(&vq->mutex);
 265         }
 266 }
 267
 268 static struct vhost_scsi_inflight *
 269 vhost_scsi_get_inflight(struct vhost_virtqueue *vq)
 270 {
 271         struct vhost_scsi_inflight *inflight;
 272         struct vhost_scsi_virtqueue *svq;
 273
 274         svq = container_of(vq, struct vhost_scsi_virtqueue, vq);
 275         inflight = &svq->inflights[svq->inflight_idx];
 276         kref_get(&inflight->kref);
 277
 278         return inflight;
 279 }
 280
 281 static void vhost_scsi_put_inflight(struct vhost_scsi_inflight *inflight)
 282 {
 283         kref_put(&inflight->kref, vhost_scsi_done_inflight);
 284 }
 285
 286 static int vhost_scsi_check_true(struct se_portal_group *se_tpg)
 287 {
 288         return 1;
 289 }
 290
 291 static int vhost_scsi_check_false(struct se_portal_group *se_tpg)
 292 {
 293         return 0;
 294 }
 295
 296 static char *vhost_scsi_get_fabric_wwn(struct se_portal_group *se_tpg)
 297 {
 298         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 299                                 struct vhost_scsi_tpg, se_tpg);
 300         struct vhost_scsi_tport *tport = tpg->tport;
 301
 302         return &tport->tport_name[0];
 303 }
 304
 305 static u16 vhost_scsi_get_tpgt(struct se_portal_group *se_tpg)
 306 {
 307         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 308                                 struct vhost_scsi_tpg, se_tpg);
 309         return tpg->tport_tpgt;
 310 }
 311
 312 static int vhost_scsi_check_prot_fabric_only(struct se_portal_group *se_tpg)
 313 {
 314         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 315                                 struct vhost_scsi_tpg, se_tpg);
 316
 317         return tpg->tv_fabric_prot_type;
 318 }
 319
 320 static u32 vhost_scsi_tpg_get_inst_index(struct se_portal_group *se_tpg)
 321 {
 322         return 1;
 323 }
 324
 325 static void vhost_scsi_release_cmd_res(struct se_cmd *se_cmd)
 326 {
 327         struct vhost_scsi_cmd *tv_cmd = container_of(se_cmd,
 328                                 struct vhost_scsi_cmd, tvc_se_cmd);
 329         struct vhost_scsi_virtqueue *svq = container_of(tv_cmd->tvc_vq,
 330                                 struct vhost_scsi_virtqueue, vq);
 331         struct vhost_scsi_inflight *inflight = tv_cmd->inflight;
 332         int i;
 333
 334         if (tv_cmd->tvc_sgl_count) {
 335                 for (i = 0; i < tv_cmd->tvc_sgl_count; i++)
 336                         put_page(sg_page(&tv_cmd->tvc_sgl[i]));
 337         }
 338         if (tv_cmd->tvc_prot_sgl_count) {
 339                 for (i = 0; i < tv_cmd->tvc_prot_sgl_count; i++)
 340                         put_page(sg_page(&tv_cmd->tvc_prot_sgl[i]));
 341         }
 342
 343         sbitmap_clear_bit(&svq->scsi_tags, se_cmd->map_tag);
 344         vhost_scsi_put_inflight(inflight);
 345 }
 346
 347 static void vhost_scsi_release_tmf_res(struct vhost_scsi_tmf *tmf)
 348 {
 349         struct vhost_scsi_tpg *tpg = tmf->tpg;
 350         struct vhost_scsi_inflight *inflight = tmf->inflight;
 351
 352         mutex_lock(&tpg->tv_tpg_mutex);
 353         list_add_tail(&tpg->tmf_queue, &tmf->queue_entry);
 354         mutex_unlock(&tpg->tv_tpg_mutex);
 355         vhost_scsi_put_inflight(inflight);
 356 }
 357
 358 static void vhost_scsi_release_cmd(struct se_cmd *se_cmd)
 359 {
 360         if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB) {
 361                 struct vhost_scsi_tmf *tmf = container_of(se_cmd,
 362                                         struct vhost_scsi_tmf, se_cmd);
 363
 364                 vhost_work_queue(&tmf->vhost->dev, &tmf->vwork);
 365         } else {
 366                 struct vhost_scsi_cmd *cmd = container_of(se_cmd,
 367                                         struct vhost_scsi_cmd, tvc_se_cmd);
 368                 struct vhost_scsi *vs = cmd->tvc_vhost;
 369
 370                 llist_add(&cmd->tvc_completion_list, &vs->vs_completion_list);
 371                 vhost_work_queue(&vs->dev, &vs->vs_completion_work);
 372         }
 373 }
 374
 375 static u32 vhost_scsi_sess_get_index(struct se_session *se_sess)
 376 {
 377         return 0;
 378 }
 379
 380 static int vhost_scsi_write_pending(struct se_cmd *se_cmd)
 381 {
 382         /* Go ahead and process the write immediately */
 383         target_execute_cmd(se_cmd);
 384         return 0;
 385 }
 386
 387 static void vhost_scsi_set_default_node_attrs(struct se_node_acl *nacl)
 388 {
 389         return;
 390 }
 391
 392 static int vhost_scsi_get_cmd_state(struct se_cmd *se_cmd)
 393 {
 394         return 0;
 395 }
 396
 397 static int vhost_scsi_queue_data_in(struct se_cmd *se_cmd)
 398 {
 399         transport_generic_free_cmd(se_cmd, 0);
 400         return 0;
 401 }
 402
 403 static int vhost_scsi_queue_status(struct se_cmd *se_cmd)
 404 {
 405         transport_generic_free_cmd(se_cmd, 0);
 406         return 0;
 407 }
 408
 409 static void vhost_scsi_queue_tm_rsp(struct se_cmd *se_cmd)
 410 {
 411         struct vhost_scsi_tmf *tmf = container_of(se_cmd, struct vhost_scsi_tmf,
 412                                                   se_cmd);
 413
 414         tmf->scsi_resp = se_cmd->se_tmr_req->response;
 415         transport_generic_free_cmd(&tmf->se_cmd, 0);
 416 }
 417
 418 static void vhost_scsi_aborted_task(struct se_cmd *se_cmd)
 419 {
 420         return;
 421 }
 422
 423 static void vhost_scsi_free_evt(struct vhost_scsi *vs, struct vhost_scsi_evt *evt)
 424 {
 425         vs->vs_events_nr--;
 426         kfree(evt);
 427 }
 428
 429 static struct vhost_scsi_evt *
 430 vhost_scsi_allocate_evt(struct vhost_scsi *vs,
 431                        u32 event, u32 reason)
 432 {
 433         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 434         struct vhost_scsi_evt *evt;
 435
 436         if (vs->vs_events_nr > VHOST_SCSI_MAX_EVENT) {
 437                 vs->vs_events_missed = true;
 438                 return NULL;
 439         }
 440
 441         evt = kzalloc(sizeof(*evt), GFP_KERNEL);
 442         if (!evt) {
 443                 vq_err(vq, "Failed to allocate vhost_scsi_evt\n");
 444                 vs->vs_events_missed = true;
 445                 return NULL;
 446         }
 447
 448         evt->event.event = cpu_to_vhost32(vq, event);
 449         evt->event.reason = cpu_to_vhost32(vq, reason);
 450         vs->vs_events_nr++;
 451
 452         return evt;
 453 }
 454
 455 static int vhost_scsi_check_stop_free(struct se_cmd *se_cmd)
 456 {
 457         return target_put_sess_cmd(se_cmd);
 458 }
 459
 460 static void
 461 vhost_scsi_do_evt_work(struct vhost_scsi *vs, struct vhost_scsi_evt *evt)
 462 {
 463         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 464         struct virtio_scsi_event *event = &evt->event;
 465         struct virtio_scsi_event __user *eventp;
 466         unsigned out, in;
 467         int head, ret;
 468
 469         if (!vhost_vq_get_backend(vq)) {
 470                 vs->vs_events_missed = true;
 471                 return;
 472         }
 473
 474 again:
 475         vhost_disable_notify(&vs->dev, vq);
 476         head = vhost_get_vq_desc(vq, vq->iov,
 477                         ARRAY_SIZE(vq->iov), &out, &in,
 478                         NULL, NULL);
 479         if (head < 0) {
 480                 vs->vs_events_missed = true;
 481                 return;
 482         }
 483         if (head == vq->num) {
 484                 if (vhost_enable_notify(&vs->dev, vq))
 485                         goto again;
 486                 vs->vs_events_missed = true;
 487                 return;
 488         }
 489
 490         if ((vq->iov[out].iov_len != sizeof(struct virtio_scsi_event))) {
 491                 vq_err(vq, "Expecting virtio_scsi_event, got %zu bytes\n",
 492                                 vq->iov[out].iov_len);
 493                 vs->vs_events_missed = true;
 494                 return;
 495         }
 496
 497         if (vs->vs_events_missed) {
 498                 event->event |= cpu_to_vhost32(vq, VIRTIO_SCSI_T_EVENTS_MISSED);
 499                 vs->vs_events_missed = false;
 500         }
 501
 502         eventp = vq->iov[out].iov_base;
 503         ret = __copy_to_user(eventp, event, sizeof(*event));
 504         if (!ret)
 505                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 506         else
 507                 vq_err(vq, "Faulted on vhost_scsi_send_event\n");
 508 }
 509
 510 static void vhost_scsi_evt_work(struct vhost_work *work)
 511 {
 512         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 513                                         vs_event_work);
 514         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 515         struct vhost_scsi_evt *evt, *t;
 516         struct llist_node *llnode;
 517
 518         mutex_lock(&vq->mutex);
 519         llnode = llist_del_all(&vs->vs_event_list);
 520         llist_for_each_entry_safe(evt, t, llnode, list) {
 521                 vhost_scsi_do_evt_work(vs, evt);
 522                 vhost_scsi_free_evt(vs, evt);
 523         }
 524         mutex_unlock(&vq->mutex);
 525 }
 526
 527 /* Fill in status and signal that we are done processing this command
 528  *
 529  * This is scheduled in the vhost work queue so we are called with the owner
 530  * process mm and can access the vring.
 531  */
 532 static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
 533 {
 534         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 535                                         vs_completion_work);
 536         DECLARE_BITMAP(signal, VHOST_SCSI_MAX_VQ);
 537         struct virtio_scsi_cmd_resp v_rsp;
 538         struct vhost_scsi_cmd *cmd, *t;
 539         struct llist_node *llnode;
 540         struct se_cmd *se_cmd;
 541         struct iov_iter iov_iter;
 542         int ret, vq;
 543
 544         bitmap_zero(signal, VHOST_SCSI_MAX_VQ);
 545         llnode = llist_del_all(&vs->vs_completion_list);
 546         llist_for_each_entry_safe(cmd, t, llnode, tvc_completion_list) {
 547                 se_cmd = &cmd->tvc_se_cmd;
 548
 549                 pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__,
 550                         cmd, se_cmd->residual_count, se_cmd->scsi_status);
 551
 552                 memset(&v_rsp, 0, sizeof(v_rsp));
 553                 v_rsp.resid = cpu_to_vhost32(cmd->tvc_vq, se_cmd->residual_count);
 554                 /* TODO is status_qualifier field needed? */
 555                 v_rsp.status = se_cmd->scsi_status;
 556                 v_rsp.sense_len = cpu_to_vhost32(cmd->tvc_vq,
 557                                                  se_cmd->scsi_sense_length);
 558                 memcpy(v_rsp.sense, cmd->tvc_sense_buf,
 559                        se_cmd->scsi_sense_length);
 560
 561                 iov_iter_init(&iov_iter, READ, &cmd->tvc_resp_iov,
 562                               cmd->tvc_in_iovs, sizeof(v_rsp));
 563                 ret = copy_to_iter(&v_rsp, sizeof(v_rsp), &iov_iter);
 564                 if (likely(ret == sizeof(v_rsp))) {
 565                         struct vhost_scsi_virtqueue *q;
 566                         vhost_add_used(cmd->tvc_vq, cmd->tvc_vq_desc, 0);
 567                         q = container_of(cmd->tvc_vq, struct vhost_scsi_virtqueue, vq);
 568                         vq = q - vs->vqs;
 569                         __set_bit(vq, signal);
 570                 } else
 571                         pr_err("Faulted on virtio_scsi_cmd_resp\n");
 572
 573                 vhost_scsi_release_cmd_res(se_cmd);
 574         }
 575
 576         vq = -1;
 577         while ((vq = find_next_bit(signal, VHOST_SCSI_MAX_VQ, vq + 1))
 578                 < VHOST_SCSI_MAX_VQ)
 579                 vhost_signal(&vs->dev, &vs->vqs[vq].vq);
 580 }
 581
 582 static struct vhost_scsi_cmd *
 583 vhost_scsi_get_cmd(struct vhost_virtqueue *vq, struct vhost_scsi_tpg *tpg,
 584                    unsigned char *cdb, u64 scsi_tag, u16 lun, u8 task_attr,
 585                    u32 exp_data_len, int data_direction)
 586 {
 587         struct vhost_scsi_virtqueue *svq = container_of(vq,
 588                                         struct vhost_scsi_virtqueue, vq);
 589         struct vhost_scsi_cmd *cmd;
 590         struct vhost_scsi_nexus *tv_nexus;
 591         struct scatterlist *sg, *prot_sg;
 592         struct page **pages;
 593         int tag;
 594
 595         tv_nexus = tpg->tpg_nexus;
 596         if (!tv_nexus) {
 597                 pr_err("Unable to locate active struct vhost_scsi_nexus\n");
 598                 return ERR_PTR(-EIO);
 599         }
 600
 601         tag = sbitmap_get(&svq->scsi_tags);
 602         if (tag < 0) {
 603                 pr_err("Unable to obtain tag for vhost_scsi_cmd\n");
 604                 return ERR_PTR(-ENOMEM);
 605         }
 606
 607         cmd = &svq->scsi_cmds[tag];
 608         sg = cmd->tvc_sgl;
 609         prot_sg = cmd->tvc_prot_sgl;
 610         pages = cmd->tvc_upages;
 611         memset(cmd, 0, sizeof(*cmd));
 612         cmd->tvc_sgl = sg;
 613         cmd->tvc_prot_sgl = prot_sg;
 614         cmd->tvc_upages = pages;
 615         cmd->tvc_se_cmd.map_tag = tag;
 616         cmd->tvc_tag = scsi_tag;
 617         cmd->tvc_lun = lun;
 618         cmd->tvc_task_attr = task_attr;
 619         cmd->tvc_exp_data_len = exp_data_len;
 620         cmd->tvc_data_direction = data_direction;
 621         cmd->tvc_nexus = tv_nexus;
 622         cmd->inflight = vhost_scsi_get_inflight(vq);
 623
 624         memcpy(cmd->tvc_cdb, cdb, VHOST_SCSI_MAX_CDB_SIZE);
 625
 626         return cmd;
 627 }
 628
 629 /*
 630  * Map a user memory range into a scatterlist
 631  *
 632  * Returns the number of scatterlist entries used or -errno on error.
 633  */
 634 static int
 635 vhost_scsi_map_to_sgl(struct vhost_scsi_cmd *cmd,
 636                       struct iov_iter *iter,
 637                       struct scatterlist *sgl,
 638                       bool write)
 639 {
 640         struct page **pages = cmd->tvc_upages;
 641         struct scatterlist *sg = sgl;
 642         ssize_t bytes;
 643         size_t offset;
 644         unsigned int npages = 0;
 645
 646         bytes = iov_iter_get_pages(iter, pages, LONG_MAX,
 647                                 VHOST_SCSI_PREALLOC_UPAGES, &offset);
 648         /* No pages were pinned */
 649         if (bytes <= 0)
 650                 return bytes < 0 ? bytes : -EFAULT;
 651
 652         iov_iter_advance(iter, bytes);
 653
 654         while (bytes) {
 655                 unsigned n = min_t(unsigned, PAGE_SIZE - offset, bytes);
 656                 sg_set_page(sg++, pages[npages++], n, offset);
 657                 bytes -= n;
 658                 offset = 0;
 659         }
 660         return npages;
 661 }
 662
 663 static int
 664 vhost_scsi_calc_sgls(struct iov_iter *iter, size_t bytes, int max_sgls)
 665 {
 666         int sgl_count = 0;
 667
 668         if (!iter || !iter->iov) {
 669                 pr_err("%s: iter->iov is NULL, but expected bytes: %zu"
 670                        " present\n", __func__, bytes);
 671                 return -EINVAL;
 672         }
 673
 674         sgl_count = iov_iter_npages(iter, 0xffff);
 675         if (sgl_count > max_sgls) {
 676                 pr_err("%s: requested sgl_count: %d exceeds pre-allocated"
 677                        " max_sgls: %d\n", __func__, sgl_count, max_sgls);
 678                 return -EINVAL;
 679         }
 680         return sgl_count;
 681 }
 682
 683 static int
 684 vhost_scsi_iov_to_sgl(struct vhost_scsi_cmd *cmd, bool write,
 685                       struct iov_iter *iter,
 686                       struct scatterlist *sg, int sg_count)
 687 {
 688         struct scatterlist *p = sg;
 689         int ret;
 690
 691         while (iov_iter_count(iter)) {
 692                 ret = vhost_scsi_map_to_sgl(cmd, iter, sg, write);
 693                 if (ret < 0) {
 694                         while (p < sg) {
 695                                 struct page *page = sg_page(p++);
 696                                 if (page)
 697                                         put_page(page);
 698                         }
 699                         return ret;
 700                 }
 701                 sg += ret;
 702         }
 703         return 0;
 704 }
 705
 706 static int
 707 vhost_scsi_mapal(struct vhost_scsi_cmd *cmd,
 708                  size_t prot_bytes, struct iov_iter *prot_iter,
 709                  size_t data_bytes, struct iov_iter *data_iter)
 710 {
 711         int sgl_count, ret;
 712         bool write = (cmd->tvc_data_direction == DMA_FROM_DEVICE);
 713
 714         if (prot_bytes) {
 715                 sgl_count = vhost_scsi_calc_sgls(prot_iter, prot_bytes,
 716                                                  VHOST_SCSI_PREALLOC_PROT_SGLS);
 717                 if (sgl_count < 0)
 718                         return sgl_count;
 719
 720                 sg_init_table(cmd->tvc_prot_sgl, sgl_count);
 721                 cmd->tvc_prot_sgl_count = sgl_count;
 722                 pr_debug("%s prot_sg %p prot_sgl_count %u\n", __func__,
 723                          cmd->tvc_prot_sgl, cmd->tvc_prot_sgl_count);
 724
 725                 ret = vhost_scsi_iov_to_sgl(cmd, write, prot_iter,
 726                                             cmd->tvc_prot_sgl,
 727                                             cmd->tvc_prot_sgl_count);
 728                 if (ret < 0) {
 729                         cmd->tvc_prot_sgl_count = 0;
 730                         return ret;
 731                 }
 732         }
 733         sgl_count = vhost_scsi_calc_sgls(data_iter, data_bytes,
 734                                          VHOST_SCSI_PREALLOC_SGLS);
 735         if (sgl_count < 0)
 736                 return sgl_count;
 737
 738         sg_init_table(cmd->tvc_sgl, sgl_count);
 739         cmd->tvc_sgl_count = sgl_count;
 740         pr_debug("%s data_sg %p data_sgl_count %u\n", __func__,
 741                   cmd->tvc_sgl, cmd->tvc_sgl_count);
 742
 743         ret = vhost_scsi_iov_to_sgl(cmd, write, data_iter,
 744                                     cmd->tvc_sgl, cmd->tvc_sgl_count);
 745         if (ret < 0) {
 746                 cmd->tvc_sgl_count = 0;
 747                 return ret;
 748         }
 749         return 0;
 750 }
 751
 752 static int vhost_scsi_to_tcm_attr(int attr)
 753 {
 754         switch (attr) {
 755         case VIRTIO_SCSI_S_SIMPLE:
 756                 return TCM_SIMPLE_TAG;
 757         case VIRTIO_SCSI_S_ORDERED:
 758                 return TCM_ORDERED_TAG;
 759         case VIRTIO_SCSI_S_HEAD:
 760                 return TCM_HEAD_TAG;
 761         case VIRTIO_SCSI_S_ACA:
 762                 return TCM_ACA_TAG;
 763         default:
 764                 break;
 765         }
 766         return TCM_SIMPLE_TAG;
 767 }
 768
 769 static void vhost_scsi_target_queue_cmd(struct vhost_scsi_cmd *cmd)
 770 {
 771         struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
 772         struct vhost_scsi_nexus *tv_nexus;
 773         struct scatterlist *sg_ptr, *sg_prot_ptr = NULL;
 774
 775         /* FIXME: BIDI operation */
 776         if (cmd->tvc_sgl_count) {
 777                 sg_ptr = cmd->tvc_sgl;
 778
 779                 if (cmd->tvc_prot_sgl_count)
 780                         sg_prot_ptr = cmd->tvc_prot_sgl;
 781                 else
 782                         se_cmd->prot_pto = true;
 783         } else {
 784                 sg_ptr = NULL;
 785         }
 786         tv_nexus = cmd->tvc_nexus;
 787
 788         se_cmd->tag = 0;
 789         target_init_cmd(se_cmd, tv_nexus->tvn_se_sess, &cmd->tvc_sense_buf[0],
 790                         cmd->tvc_lun, cmd->tvc_exp_data_len,
 791                         vhost_scsi_to_tcm_attr(cmd->tvc_task_attr),
 792                         cmd->tvc_data_direction, TARGET_SCF_ACK_KREF);
 793
 794         if (target_submit_prep(se_cmd, cmd->tvc_cdb, sg_ptr,
 795                                cmd->tvc_sgl_count, NULL, 0, sg_prot_ptr,
 796                                cmd->tvc_prot_sgl_count, GFP_KERNEL))
 797                 return;
 798
 799         target_queue_submission(se_cmd);
 800 }
 801
 802 static void
 803 vhost_scsi_send_bad_target(struct vhost_scsi *vs,
 804                            struct vhost_virtqueue *vq,
 805                            int head, unsigned out)
 806 {
 807         struct virtio_scsi_cmd_resp __user *resp;
 808         struct virtio_scsi_cmd_resp rsp;
 809         int ret;
 810
 811         memset(&rsp, 0, sizeof(rsp));
 812         rsp.response = VIRTIO_SCSI_S_BAD_TARGET;
 813         resp = vq->iov[out].iov_base;
 814         ret = __copy_to_user(resp, &rsp, sizeof(rsp));
 815         if (!ret)
 816                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 817         else
 818                 pr_err("Faulted on virtio_scsi_cmd_resp\n");
 819 }
 820
 821 static int
 822 vhost_scsi_get_desc(struct vhost_scsi *vs, struct vhost_virtqueue *vq,
 823                     struct vhost_scsi_ctx *vc)
 824 {
 825         int ret = -ENXIO;
 826
 827         vc->head = vhost_get_vq_desc(vq, vq->iov,
 828                                      ARRAY_SIZE(vq->iov), &vc->out, &vc->in,
 829                                      NULL, NULL);
 830
 831         pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n",
 832                  vc->head, vc->out, vc->in);
 833
 834         /* On error, stop handling until the next kick. */
 835         if (unlikely(vc->head < 0))
 836                 goto done;
 837
 838         /* Nothing new?  Wait for eventfd to tell us they refilled. */
 839         if (vc->head == vq->num) {
 840                 if (unlikely(vhost_enable_notify(&vs->dev, vq))) {
 841                         vhost_disable_notify(&vs->dev, vq);
 842                         ret = -EAGAIN;
 843                 }
 844                 goto done;
 845         }
 846
 847         /*
 848          * Get the size of request and response buffers.
 849          * FIXME: Not correct for BIDI operation
 850          */
 851         vc->out_size = iov_length(vq->iov, vc->out);
 852         vc->in_size = iov_length(&vq->iov[vc->out], vc->in);
 853
 854         /*
 855          * Copy over the virtio-scsi request header, which for a
 856          * ANY_LAYOUT enabled guest may span multiple iovecs, or a
 857          * single iovec may contain both the header + outgoing
 858          * WRITE payloads.
 859          *
 860          * copy_from_iter() will advance out_iter, so that it will
 861          * point at the start of the outgoing WRITE payload, if
 862          * DMA_TO_DEVICE is set.
 863          */
 864         iov_iter_init(&vc->out_iter, WRITE, vq->iov, vc->out, vc->out_size);
 865         ret = 0;
 866
 867 done:
 868         return ret;
 869 }
 870
 871 static int
 872 vhost_scsi_chk_size(struct vhost_virtqueue *vq, struct vhost_scsi_ctx *vc)
 873 {
 874         if (unlikely(vc->in_size < vc->rsp_size)) {
 875                 vq_err(vq,
 876                        "Response buf too small, need min %zu bytes got %zu",
 877                        vc->rsp_size, vc->in_size);
 878                 return -EINVAL;
 879         } else if (unlikely(vc->out_size < vc->req_size)) {
 880                 vq_err(vq,
 881                        "Request buf too small, need min %zu bytes got %zu",
 882                        vc->req_size, vc->out_size);
 883                 return -EIO;
 884         }
 885
 886         return 0;
 887 }
 888
 889 static int
 890 vhost_scsi_get_req(struct vhost_virtqueue *vq, struct vhost_scsi_ctx *vc,
 891                    struct vhost_scsi_tpg **tpgp)
 892 {
 893         int ret = -EIO;
 894
 895         if (unlikely(!copy_from_iter_full(vc->req, vc->req_size,
 896                                           &vc->out_iter))) {
 897                 vq_err(vq, "Faulted on copy_from_iter_full\n");
 898         } else if (unlikely(*vc->lunp != 1)) {
 899                 /* virtio-scsi spec requires byte 0 of the lun to be 1 */
 900                 vq_err(vq, "Illegal virtio-scsi lun: %u\n", *vc->lunp);
 901         } else {
 902                 struct vhost_scsi_tpg **vs_tpg, *tpg;
 903
 904                 vs_tpg = vhost_vq_get_backend(vq);      /* validated at handler entry */
 905
 906                 tpg = READ_ONCE(vs_tpg[*vc->target]);
 907                 if (unlikely(!tpg)) {
 908                         vq_err(vq, "Target 0x%x does not exist\n", *vc->target);
 909                 } else {
 910                         if (tpgp)
 911                                 *tpgp = tpg;
 912                         ret = 0;
 913                 }
 914         }
 915
 916         return ret;
 917 }
 918
 919 static u16 vhost_buf_to_lun(u8 *lun_buf)
 920 {
 921         return ((lun_buf[2] << 8) | lun_buf[3]) & 0x3FFF;
 922 }
 923
 924 static void
 925 vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
 926 {
 927         struct vhost_scsi_tpg **vs_tpg, *tpg;
 928         struct virtio_scsi_cmd_req v_req;
 929         struct virtio_scsi_cmd_req_pi v_req_pi;
 930         struct vhost_scsi_ctx vc;
 931         struct vhost_scsi_cmd *cmd;
 932         struct iov_iter in_iter, prot_iter, data_iter;
 933         u64 tag;
 934         u32 exp_data_len, data_direction;
 935         int ret, prot_bytes, c = 0;
 936         u16 lun;
 937         u8 task_attr;
 938         bool t10_pi = vhost_has_feature(vq, VIRTIO_SCSI_F_T10_PI);
 939         void *cdb;
 940
 941         mutex_lock(&vq->mutex);
 942         /*
 943          * We can handle the vq only after the endpoint is setup by calling the
 944          * VHOST_SCSI_SET_ENDPOINT ioctl.
 945          */
 946         vs_tpg = vhost_vq_get_backend(vq);
 947         if (!vs_tpg)
 948                 goto out;
 949
 950         memset(&vc, 0, sizeof(vc));
 951         vc.rsp_size = sizeof(struct virtio_scsi_cmd_resp);
 952
 953         vhost_disable_notify(&vs->dev, vq);
 954
 955         do {
 956                 ret = vhost_scsi_get_desc(vs, vq, &vc);
 957                 if (ret)
 958                         goto err;
 959
 960                 /*
 961                  * Setup pointers and values based upon different virtio-scsi
 962                  * request header if T10_PI is enabled in KVM guest.
 963                  */
 964                 if (t10_pi) {
 965                         vc.req = &v_req_pi;
 966                         vc.req_size = sizeof(v_req_pi);
 967                         vc.lunp = &v_req_pi.lun[0];
 968                         vc.target = &v_req_pi.lun[1];
 969                 } else {
 970                         vc.req = &v_req;
 971                         vc.req_size = sizeof(v_req);
 972                         vc.lunp = &v_req.lun[0];
 973                         vc.target = &v_req.lun[1];
 974                 }
 975
 976                 /*
 977                  * Validate the size of request and response buffers.
 978                  * Check for a sane response buffer so we can report
 979                  * early errors back to the guest.
 980                  */
 981                 ret = vhost_scsi_chk_size(vq, &vc);
 982                 if (ret)
 983                         goto err;
 984
 985                 ret = vhost_scsi_get_req(vq, &vc, &tpg);
 986                 if (ret)
 987                         goto err;
 988
 989                 ret = -EIO;     /* bad target on any error from here on */
 990
 991                 /*
 992                  * Determine data_direction by calculating the total outgoing
 993                  * iovec sizes + incoming iovec sizes vs. virtio-scsi request +
 994                  * response headers respectively.
 995                  *
 996                  * For DMA_TO_DEVICE this is out_iter, which is already pointing
 997                  * to the right place.
 998                  *
 999                  * For DMA_FROM_DEVICE, the iovec will be just past the end
1000                  * of the virtio-scsi response header in either the same
1001                  * or immediately following iovec.
1002                  *
1003                  * Any associated T10_PI bytes for the outgoing / incoming
1004                  * payloads are included in calculation of exp_data_len here.
1005                  */
1006                 prot_bytes = 0;
1007
1008                 if (vc.out_size > vc.req_size) {
1009                         data_direction = DMA_TO_DEVICE;
1010                         exp_data_len = vc.out_size - vc.req_size;
1011                         data_iter = vc.out_iter;
1012                 } else if (vc.in_size > vc.rsp_size) {
1013                         data_direction = DMA_FROM_DEVICE;
1014                         exp_data_len = vc.in_size - vc.rsp_size;
1015
1016                         iov_iter_init(&in_iter, READ, &vq->iov[vc.out], vc.in,
1017                                       vc.rsp_size + exp_data_len);
1018                         iov_iter_advance(&in_iter, vc.rsp_size);
1019                         data_iter = in_iter;
1020                 } else {
1021                         data_direction = DMA_NONE;
1022                         exp_data_len = 0;
1023                 }
1024                 /*
1025                  * If T10_PI header + payload is present, setup prot_iter values
1026                  * and recalculate data_iter for vhost_scsi_mapal() mapping to
1027                  * host scatterlists via get_user_pages_fast().
1028                  */
1029                 if (t10_pi) {
1030                         if (v_req_pi.pi_bytesout) {
1031                                 if (data_direction != DMA_TO_DEVICE) {
1032                                         vq_err(vq, "Received non zero pi_bytesout,"
1033                                                 " but wrong data_direction\n");
1034                                         goto err;
1035                                 }
1036                                 prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesout);
1037                         } else if (v_req_pi.pi_bytesin) {
1038                                 if (data_direction != DMA_FROM_DEVICE) {
1039                                         vq_err(vq, "Received non zero pi_bytesin,"
1040                                                 " but wrong data_direction\n");
1041                                         goto err;
1042                                 }
1043                                 prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesin);
1044                         }
1045                         /*
1046                          * Set prot_iter to data_iter and truncate it to
1047                          * prot_bytes, and advance data_iter past any
1048                          * preceeding prot_bytes that may be present.
1049                          *
1050                          * Also fix up the exp_data_len to reflect only the
1051                          * actual data payload length.
1052                          */
1053                         if (prot_bytes) {
1054                                 exp_data_len -= prot_bytes;
1055                                 prot_iter = data_iter;
1056                                 iov_iter_truncate(&prot_iter, prot_bytes);
1057                                 iov_iter_advance(&data_iter, prot_bytes);
1058                         }
1059                         tag = vhost64_to_cpu(vq, v_req_pi.tag);
1060                         task_attr = v_req_pi.task_attr;
1061                         cdb = &v_req_pi.cdb[0];
1062                         lun = vhost_buf_to_lun(v_req_pi.lun);
1063                 } else {
1064                         tag = vhost64_to_cpu(vq, v_req.tag);
1065                         task_attr = v_req.task_attr;
1066                         cdb = &v_req.cdb[0];
1067                         lun = vhost_buf_to_lun(v_req.lun);
1068                 }
1069                 /*
1070                  * Check that the received CDB size does not exceeded our
1071                  * hardcoded max for vhost-scsi, then get a pre-allocated
1072                  * cmd descriptor for the new virtio-scsi tag.
1073                  *
1074                  * TODO what if cdb was too small for varlen cdb header?
1075                  */
1076                 if (unlikely(scsi_command_size(cdb) > VHOST_SCSI_MAX_CDB_SIZE)) {
1077                         vq_err(vq, "Received SCSI CDB with command_size: %d that"
1078                                 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1079                                 scsi_command_size(cdb), VHOST_SCSI_MAX_CDB_SIZE);
1080                                 goto err;
1081                 }
1082                 cmd = vhost_scsi_get_cmd(vq, tpg, cdb, tag, lun, task_attr,
1083                                          exp_data_len + prot_bytes,
1084                                          data_direction);
1085                 if (IS_ERR(cmd)) {
1086                         vq_err(vq, "vhost_scsi_get_cmd failed %ld\n",
1087                                PTR_ERR(cmd));
1088                         goto err;
1089                 }
1090                 cmd->tvc_vhost = vs;
1091                 cmd->tvc_vq = vq;
1092                 cmd->tvc_resp_iov = vq->iov[vc.out];
1093                 cmd->tvc_in_iovs = vc.in;
1094
1095                 pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n",
1096                          cmd->tvc_cdb[0], cmd->tvc_lun);
1097                 pr_debug("cmd: %p exp_data_len: %d, prot_bytes: %d data_direction:"
1098                          " %d\n", cmd, exp_data_len, prot_bytes, data_direction);
1099
1100                 if (data_direction != DMA_NONE) {
1101                         if (unlikely(vhost_scsi_mapal(cmd, prot_bytes,
1102                                                       &prot_iter, exp_data_len,
1103                                                       &data_iter))) {
1104                                 vq_err(vq, "Failed to map iov to sgl\n");
1105                                 vhost_scsi_release_cmd_res(&cmd->tvc_se_cmd);
1106                                 goto err;
1107                         }
1108                 }
1109                 /*
1110                  * Save the descriptor from vhost_get_vq_desc() to be used to
1111                  * complete the virtio-scsi request in TCM callback context via
1112                  * vhost_scsi_queue_data_in() and vhost_scsi_queue_status()
1113                  */
1114                 cmd->tvc_vq_desc = vc.head;
1115                 vhost_scsi_target_queue_cmd(cmd);
1116                 ret = 0;
1117 err:
1118                 /*
1119                  * ENXIO:  No more requests, or read error, wait for next kick
1120                  * EINVAL: Invalid response buffer, drop the request
1121                  * EIO:    Respond with bad target
1122                  * EAGAIN: Pending request
1123                  */
1124                 if (ret == -ENXIO)
1125                         break;
1126                 else if (ret == -EIO)
1127                         vhost_scsi_send_bad_target(vs, vq, vc.head, vc.out);
1128         } while (likely(!vhost_exceeds_weight(vq, ++c, 0)));
1129 out:
1130         mutex_unlock(&vq->mutex);
1131 }
1132
1133 static void
1134 vhost_scsi_send_tmf_resp(struct vhost_scsi *vs, struct vhost_virtqueue *vq,
1135                          int in_iovs, int vq_desc, struct iovec *resp_iov,
1136                          int tmf_resp_code)
1137 {
1138         struct virtio_scsi_ctrl_tmf_resp rsp;
1139         struct iov_iter iov_iter;
1140         int ret;
1141
1142         pr_debug("%s\n", __func__);
1143         memset(&rsp, 0, sizeof(rsp));
1144         rsp.response = tmf_resp_code;
1145
1146         iov_iter_init(&iov_iter, READ, resp_iov, in_iovs, sizeof(rsp));
1147
1148         ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter);
1149         if (likely(ret == sizeof(rsp)))
1150                 vhost_add_used_and_signal(&vs->dev, vq, vq_desc, 0);
1151         else
1152                 pr_err("Faulted on virtio_scsi_ctrl_tmf_resp\n");
1153 }
1154
1155 static void vhost_scsi_tmf_resp_work(struct vhost_work *work)
1156 {
1157         struct vhost_scsi_tmf *tmf = container_of(work, struct vhost_scsi_tmf,
1158                                                   vwork);
1159         int resp_code;
1160
1161         if (tmf->scsi_resp == TMR_FUNCTION_COMPLETE)
1162                 resp_code = VIRTIO_SCSI_S_FUNCTION_SUCCEEDED;
1163         else
1164                 resp_code = VIRTIO_SCSI_S_FUNCTION_REJECTED;
1165
1166         vhost_scsi_send_tmf_resp(tmf->vhost, &tmf->svq->vq, tmf->in_iovs,
1167                                  tmf->vq_desc, &tmf->resp_iov, resp_code);
1168         vhost_scsi_release_tmf_res(tmf);
1169 }
1170
1171 static void
1172 vhost_scsi_handle_tmf(struct vhost_scsi *vs, struct vhost_scsi_tpg *tpg,
1173                       struct vhost_virtqueue *vq,
1174                       struct virtio_scsi_ctrl_tmf_req *vtmf,
1175                       struct vhost_scsi_ctx *vc)
1176 {
1177         struct vhost_scsi_virtqueue *svq = container_of(vq,
1178                                         struct vhost_scsi_virtqueue, vq);
1179         struct vhost_scsi_tmf *tmf;
1180
1181         if (vhost32_to_cpu(vq, vtmf->subtype) !=
1182             VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET)
1183                 goto send_reject;
1184
1185         if (!tpg->tpg_nexus || !tpg->tpg_nexus->tvn_se_sess) {
1186                 pr_err("Unable to locate active struct vhost_scsi_nexus for LUN RESET.\n");
1187                 goto send_reject;
1188         }
1189
1190         mutex_lock(&tpg->tv_tpg_mutex);
1191         if (list_empty(&tpg->tmf_queue)) {
1192                 pr_err("Missing reserve TMF. Could not handle LUN RESET.\n");
1193                 mutex_unlock(&tpg->tv_tpg_mutex);
1194                 goto send_reject;
1195         }
1196
1197         tmf = list_first_entry(&tpg->tmf_queue, struct vhost_scsi_tmf,
1198                                queue_entry);
1199         list_del_init(&tmf->queue_entry);
1200         mutex_unlock(&tpg->tv_tpg_mutex);
1201
1202         tmf->tpg = tpg;
1203         tmf->vhost = vs;
1204         tmf->svq = svq;
1205         tmf->resp_iov = vq->iov[vc->out];
1206         tmf->vq_desc = vc->head;
1207         tmf->in_iovs = vc->in;
1208         tmf->inflight = vhost_scsi_get_inflight(vq);
1209
1210         if (target_submit_tmr(&tmf->se_cmd, tpg->tpg_nexus->tvn_se_sess, NULL,
1211                               vhost_buf_to_lun(vtmf->lun), NULL,
1212                               TMR_LUN_RESET, GFP_KERNEL, 0,
1213                               TARGET_SCF_ACK_KREF) < 0) {
1214                 vhost_scsi_release_tmf_res(tmf);
1215                 goto send_reject;
1216         }
1217
1218         return;
1219
1220 send_reject:
1221         vhost_scsi_send_tmf_resp(vs, vq, vc->in, vc->head, &vq->iov[vc->out],
1222                                  VIRTIO_SCSI_S_FUNCTION_REJECTED);
1223 }
1224
1225 static void
1226 vhost_scsi_send_an_resp(struct vhost_scsi *vs,
1227                         struct vhost_virtqueue *vq,
1228                         struct vhost_scsi_ctx *vc)
1229 {
1230         struct virtio_scsi_ctrl_an_resp rsp;
1231         struct iov_iter iov_iter;
1232         int ret;
1233
1234         pr_debug("%s\n", __func__);
1235         memset(&rsp, 0, sizeof(rsp));   /* event_actual = 0 */
1236         rsp.response = VIRTIO_SCSI_S_OK;
1237
1238         iov_iter_init(&iov_iter, READ, &vq->iov[vc->out], vc->in, sizeof(rsp));
1239
1240         ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter);
1241         if (likely(ret == sizeof(rsp)))
1242                 vhost_add_used_and_signal(&vs->dev, vq, vc->head, 0);
1243         else
1244                 pr_err("Faulted on virtio_scsi_ctrl_an_resp\n");
1245 }
1246
1247 static void
1248 vhost_scsi_ctl_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
1249 {
1250         struct vhost_scsi_tpg *tpg;
1251         union {
1252                 __virtio32 type;
1253                 struct virtio_scsi_ctrl_an_req an;
1254                 struct virtio_scsi_ctrl_tmf_req tmf;
1255         } v_req;
1256         struct vhost_scsi_ctx vc;
1257         size_t typ_size;
1258         int ret, c = 0;
1259
1260         mutex_lock(&vq->mutex);
1261         /*
1262          * We can handle the vq only after the endpoint is setup by calling the
1263          * VHOST_SCSI_SET_ENDPOINT ioctl.
1264          */
1265         if (!vhost_vq_get_backend(vq))
1266                 goto out;
1267
1268         memset(&vc, 0, sizeof(vc));
1269
1270         vhost_disable_notify(&vs->dev, vq);
1271
1272         do {
1273                 ret = vhost_scsi_get_desc(vs, vq, &vc);
1274                 if (ret)
1275                         goto err;
1276
1277                 /*
1278                  * Get the request type first in order to setup
1279                  * other parameters dependent on the type.
1280                  */
1281                 vc.req = &v_req.type;
1282                 typ_size = sizeof(v_req.type);
1283
1284                 if (unlikely(!copy_from_iter_full(vc.req, typ_size,
1285                                                   &vc.out_iter))) {
1286                         vq_err(vq, "Faulted on copy_from_iter tmf type\n");
1287                         /*
1288                          * The size of the response buffer depends on the
1289                          * request type and must be validated against it.
1290                          * Since the request type is not known, don't send
1291                          * a response.
1292                          */
1293                         continue;
1294                 }
1295
1296                 switch (vhost32_to_cpu(vq, v_req.type)) {
1297                 case VIRTIO_SCSI_T_TMF:
1298                         vc.req = &v_req.tmf;
1299                         vc.req_size = sizeof(struct virtio_scsi_ctrl_tmf_req);
1300                         vc.rsp_size = sizeof(struct virtio_scsi_ctrl_tmf_resp);
1301                         vc.lunp = &v_req.tmf.lun[0];
1302                         vc.target = &v_req.tmf.lun[1];
1303                         break;
1304                 case VIRTIO_SCSI_T_AN_QUERY:
1305                 case VIRTIO_SCSI_T_AN_SUBSCRIBE:
1306                         vc.req = &v_req.an;
1307                         vc.req_size = sizeof(struct virtio_scsi_ctrl_an_req);
1308                         vc.rsp_size = sizeof(struct virtio_scsi_ctrl_an_resp);
1309                         vc.lunp = &v_req.an.lun[0];
1310                         vc.target = NULL;
1311                         break;
1312                 default:
1313                         vq_err(vq, "Unknown control request %d", v_req.type);
1314                         continue;
1315                 }
1316
1317                 /*
1318                  * Validate the size of request and response buffers.
1319                  * Check for a sane response buffer so we can report
1320                  * early errors back to the guest.
1321                  */
1322                 ret = vhost_scsi_chk_size(vq, &vc);
1323                 if (ret)
1324                         goto err;
1325
1326                 /*
1327                  * Get the rest of the request now that its size is known.
1328                  */
1329                 vc.req += typ_size;
1330                 vc.req_size -= typ_size;
1331
1332                 ret = vhost_scsi_get_req(vq, &vc, &tpg);
1333                 if (ret)
1334                         goto err;
1335
1336                 if (v_req.type == VIRTIO_SCSI_T_TMF)
1337                         vhost_scsi_handle_tmf(vs, tpg, vq, &v_req.tmf, &vc);
1338                 else
1339                         vhost_scsi_send_an_resp(vs, vq, &vc);
1340 err:
1341                 /*
1342                  * ENXIO:  No more requests, or read error, wait for next kick
1343                  * EINVAL: Invalid response buffer, drop the request
1344                  * EIO:    Respond with bad target
1345                  * EAGAIN: Pending request
1346                  */
1347                 if (ret == -ENXIO)
1348                         break;
1349                 else if (ret == -EIO)
1350                         vhost_scsi_send_bad_target(vs, vq, vc.head, vc.out);
1351         } while (likely(!vhost_exceeds_weight(vq, ++c, 0)));
1352 out:
1353         mutex_unlock(&vq->mutex);
1354 }
1355
1356 static void vhost_scsi_ctl_handle_kick(struct vhost_work *work)
1357 {
1358         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1359                                                 poll.work);
1360         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1361
1362         pr_debug("%s: The handling func for control queue.\n", __func__);
1363         vhost_scsi_ctl_handle_vq(vs, vq);
1364 }
1365
1366 static void
1367 vhost_scsi_send_evt(struct vhost_scsi *vs,
1368                    struct vhost_scsi_tpg *tpg,
1369                    struct se_lun *lun,
1370                    u32 event,
1371                    u32 reason)
1372 {
1373         struct vhost_scsi_evt *evt;
1374
1375         evt = vhost_scsi_allocate_evt(vs, event, reason);
1376         if (!evt)
1377                 return;
1378
1379         if (tpg && lun) {
1380                 /* TODO: share lun setup code with virtio-scsi.ko */
1381                 /*
1382                  * Note: evt->event is zeroed when we allocate it and
1383                  * lun[4-7] need to be zero according to virtio-scsi spec.
1384                  */
1385                 evt->event.lun[0] = 0x01;
1386                 evt->event.lun[1] = tpg->tport_tpgt;
1387                 if (lun->unpacked_lun >= 256)
1388                         evt->event.lun[2] = lun->unpacked_lun >> 8 | 0x40 ;
1389                 evt->event.lun[3] = lun->unpacked_lun & 0xFF;
1390         }
1391
1392         llist_add(&evt->list, &vs->vs_event_list);
1393         vhost_work_queue(&vs->dev, &vs->vs_event_work);
1394 }
1395
1396 static void vhost_scsi_evt_handle_kick(struct vhost_work *work)
1397 {
1398         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1399                                                 poll.work);
1400         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1401
1402         mutex_lock(&vq->mutex);
1403         if (!vhost_vq_get_backend(vq))
1404                 goto out;
1405
1406         if (vs->vs_events_missed)
1407                 vhost_scsi_send_evt(vs, NULL, NULL, VIRTIO_SCSI_T_NO_EVENT, 0);
1408 out:
1409         mutex_unlock(&vq->mutex);
1410 }
1411
1412 static void vhost_scsi_handle_kick(struct vhost_work *work)
1413 {
1414         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1415                                                 poll.work);
1416         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1417
1418         vhost_scsi_handle_vq(vs, vq);
1419 }
1420
1421 /* Callers must hold dev mutex */
1422 static void vhost_scsi_flush(struct vhost_scsi *vs)
1423 {
1424         struct vhost_scsi_inflight *old_inflight[VHOST_SCSI_MAX_VQ];
1425         int i;
1426
1427         /* Init new inflight and remember the old inflight */
1428         vhost_scsi_init_inflight(vs, old_inflight);
1429
1430         /*
1431          * The inflight->kref was initialized to 1. We decrement it here to
1432          * indicate the start of the flush operation so that it will reach 0
1433          * when all the reqs are finished.
1434          */
1435         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1436                 kref_put(&old_inflight[i]->kref, vhost_scsi_done_inflight);
1437
1438         /* Flush both the vhost poll and vhost work */
1439         vhost_work_dev_flush(&vs->dev);
1440
1441         /* Wait for all reqs issued before the flush to be finished */
1442         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1443                 wait_for_completion(&old_inflight[i]->comp);
1444 }
1445
1446 static void vhost_scsi_destroy_vq_cmds(struct vhost_virtqueue *vq)
1447 {
1448         struct vhost_scsi_virtqueue *svq = container_of(vq,
1449                                         struct vhost_scsi_virtqueue, vq);
1450         struct vhost_scsi_cmd *tv_cmd;
1451         unsigned int i;
1452
1453         if (!svq->scsi_cmds)
1454                 return;
1455
1456         for (i = 0; i < svq->max_cmds; i++) {
1457                 tv_cmd = &svq->scsi_cmds[i];
1458
1459                 kfree(tv_cmd->tvc_sgl);
1460                 kfree(tv_cmd->tvc_prot_sgl);
1461                 kfree(tv_cmd->tvc_upages);
1462         }
1463
1464         sbitmap_free(&svq->scsi_tags);
1465         kfree(svq->scsi_cmds);
1466         svq->scsi_cmds = NULL;
1467 }
1468
1469 static int vhost_scsi_setup_vq_cmds(struct vhost_virtqueue *vq, int max_cmds)
1470 {
1471         struct vhost_scsi_virtqueue *svq = container_of(vq,
1472                                         struct vhost_scsi_virtqueue, vq);
1473         struct vhost_scsi_cmd *tv_cmd;
1474         unsigned int i;
1475
1476         if (svq->scsi_cmds)
1477                 return 0;
1478
1479         if (sbitmap_init_node(&svq->scsi_tags, max_cmds, -1, GFP_KERNEL,
1480                               NUMA_NO_NODE, false, true))
1481                 return -ENOMEM;
1482         svq->max_cmds = max_cmds;
1483
1484         svq->scsi_cmds = kcalloc(max_cmds, sizeof(*tv_cmd), GFP_KERNEL);
1485         if (!svq->scsi_cmds) {
1486                 sbitmap_free(&svq->scsi_tags);
1487                 return -ENOMEM;
1488         }
1489
1490         for (i = 0; i < max_cmds; i++) {
1491                 tv_cmd = &svq->scsi_cmds[i];
1492
1493                 tv_cmd->tvc_sgl = kcalloc(VHOST_SCSI_PREALLOC_SGLS,
1494                                           sizeof(struct scatterlist),
1495                                           GFP_KERNEL);
1496                 if (!tv_cmd->tvc_sgl) {
1497                         pr_err("Unable to allocate tv_cmd->tvc_sgl\n");
1498                         goto out;
1499                 }
1500
1501                 tv_cmd->tvc_upages = kcalloc(VHOST_SCSI_PREALLOC_UPAGES,
1502                                              sizeof(struct page *),
1503                                              GFP_KERNEL);
1504                 if (!tv_cmd->tvc_upages) {
1505                         pr_err("Unable to allocate tv_cmd->tvc_upages\n");
1506                         goto out;
1507                 }
1508
1509                 tv_cmd->tvc_prot_sgl = kcalloc(VHOST_SCSI_PREALLOC_PROT_SGLS,
1510                                                sizeof(struct scatterlist),
1511                                                GFP_KERNEL);
1512                 if (!tv_cmd->tvc_prot_sgl) {
1513                         pr_err("Unable to allocate tv_cmd->tvc_prot_sgl\n");
1514                         goto out;
1515                 }
1516         }
1517         return 0;
1518 out:
1519         vhost_scsi_destroy_vq_cmds(vq);
1520         return -ENOMEM;
1521 }
1522
1523 /*
1524  * Called from vhost_scsi_ioctl() context to walk the list of available
1525  * vhost_scsi_tpg with an active struct vhost_scsi_nexus
1526  *
1527  *  The lock nesting rule is:
1528  *    vhost_scsi_mutex -> vs->dev.mutex -> tpg->tv_tpg_mutex -> vq->mutex
1529  */
1530 static int
1531 vhost_scsi_set_endpoint(struct vhost_scsi *vs,
1532                         struct vhost_scsi_target *t)
1533 {
1534         struct se_portal_group *se_tpg;
1535         struct vhost_scsi_tport *tv_tport;
1536         struct vhost_scsi_tpg *tpg;
1537         struct vhost_scsi_tpg **vs_tpg;
1538         struct vhost_virtqueue *vq;
1539         int index, ret, i, len;
1540         bool match = false;
1541
1542         mutex_lock(&vhost_scsi_mutex);
1543         mutex_lock(&vs->dev.mutex);
1544
1545         /* Verify that ring has been setup correctly. */
1546         for (index = 0; index < vs->dev.nvqs; ++index) {
1547                 /* Verify that ring has been setup correctly. */
1548                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1549                         ret = -EFAULT;
1550                         goto out;
1551                 }
1552         }
1553
1554         len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET;
1555         vs_tpg = kzalloc(len, GFP_KERNEL);
1556         if (!vs_tpg) {
1557                 ret = -ENOMEM;
1558                 goto out;
1559         }
1560         if (vs->vs_tpg)
1561                 memcpy(vs_tpg, vs->vs_tpg, len);
1562
1563         list_for_each_entry(tpg, &vhost_scsi_list, tv_tpg_list) {
1564                 mutex_lock(&tpg->tv_tpg_mutex);
1565                 if (!tpg->tpg_nexus) {
1566                         mutex_unlock(&tpg->tv_tpg_mutex);
1567                         continue;
1568                 }
1569                 if (tpg->tv_tpg_vhost_count != 0) {
1570                         mutex_unlock(&tpg->tv_tpg_mutex);
1571                         continue;
1572                 }
1573                 tv_tport = tpg->tport;
1574
1575                 if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1576                         if (vs->vs_tpg && vs->vs_tpg[tpg->tport_tpgt]) {
1577                                 mutex_unlock(&tpg->tv_tpg_mutex);
1578                                 ret = -EEXIST;
1579                                 goto undepend;
1580                         }
1581                         /*
1582                          * In order to ensure individual vhost-scsi configfs
1583                          * groups cannot be removed while in use by vhost ioctl,
1584                          * go ahead and take an explicit se_tpg->tpg_group.cg_item
1585                          * dependency now.
1586                          */
1587                         se_tpg = &tpg->se_tpg;
1588                         ret = target_depend_item(&se_tpg->tpg_group.cg_item);
1589                         if (ret) {
1590                                 pr_warn("target_depend_item() failed: %d\n", ret);
1591                                 mutex_unlock(&tpg->tv_tpg_mutex);
1592                                 goto undepend;
1593                         }
1594                         tpg->tv_tpg_vhost_count++;
1595                         tpg->vhost_scsi = vs;
1596                         vs_tpg[tpg->tport_tpgt] = tpg;
1597                         match = true;
1598                 }
1599                 mutex_unlock(&tpg->tv_tpg_mutex);
1600         }
1601
1602         if (match) {
1603                 memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
1604                        sizeof(vs->vs_vhost_wwpn));
1605
1606                 for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++) {
1607                         vq = &vs->vqs[i].vq;
1608                         if (!vhost_vq_is_setup(vq))
1609                                 continue;
1610
1611                         ret = vhost_scsi_setup_vq_cmds(vq, vq->num);
1612                         if (ret)
1613                                 goto destroy_vq_cmds;
1614                 }
1615
1616                 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1617                         vq = &vs->vqs[i].vq;
1618                         mutex_lock(&vq->mutex);
1619                         vhost_vq_set_backend(vq, vs_tpg);
1620                         vhost_vq_init_access(vq);
1621                         mutex_unlock(&vq->mutex);
1622                 }
1623                 ret = 0;
1624         } else {
1625                 ret = -EEXIST;
1626         }
1627
1628         /*
1629          * Act as synchronize_rcu to make sure access to
1630          * old vs->vs_tpg is finished.
1631          */
1632         vhost_scsi_flush(vs);
1633         kfree(vs->vs_tpg);
1634         vs->vs_tpg = vs_tpg;
1635         goto out;
1636
1637 destroy_vq_cmds:
1638         for (i--; i >= VHOST_SCSI_VQ_IO; i--) {
1639                 if (!vhost_vq_get_backend(&vs->vqs[i].vq))
1640                         vhost_scsi_destroy_vq_cmds(&vs->vqs[i].vq);
1641         }
1642 undepend:
1643         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1644                 tpg = vs_tpg[i];
1645                 if (tpg) {
1646                         tpg->tv_tpg_vhost_count--;
1647                         target_undepend_item(&tpg->se_tpg.tpg_group.cg_item);
1648                 }
1649         }
1650         kfree(vs_tpg);
1651 out:
1652         mutex_unlock(&vs->dev.mutex);
1653         mutex_unlock(&vhost_scsi_mutex);
1654         return ret;
1655 }
1656
1657 static int
1658 vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
1659                           struct vhost_scsi_target *t)
1660 {
1661         struct se_portal_group *se_tpg;
1662         struct vhost_scsi_tport *tv_tport;
1663         struct vhost_scsi_tpg *tpg;
1664         struct vhost_virtqueue *vq;
1665         bool match = false;
1666         int index, ret, i;
1667         u8 target;
1668
1669         mutex_lock(&vhost_scsi_mutex);
1670         mutex_lock(&vs->dev.mutex);
1671         /* Verify that ring has been setup correctly. */
1672         for (index = 0; index < vs->dev.nvqs; ++index) {
1673                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1674                         ret = -EFAULT;
1675                         goto err_dev;
1676                 }
1677         }
1678
1679         if (!vs->vs_tpg) {
1680                 ret = 0;
1681                 goto err_dev;
1682         }
1683
1684         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1685                 target = i;
1686                 tpg = vs->vs_tpg[target];
1687                 if (!tpg)
1688                         continue;
1689
1690                 mutex_lock(&tpg->tv_tpg_mutex);
1691                 tv_tport = tpg->tport;
1692                 if (!tv_tport) {
1693                         ret = -ENODEV;
1694                         goto err_tpg;
1695                 }
1696
1697                 if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1698                         pr_warn("tv_tport->tport_name: %s, tpg->tport_tpgt: %hu"
1699                                 " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
1700                                 tv_tport->tport_name, tpg->tport_tpgt,
1701                                 t->vhost_wwpn, t->vhost_tpgt);
1702                         ret = -EINVAL;
1703                         goto err_tpg;
1704                 }
1705                 tpg->tv_tpg_vhost_count--;
1706                 tpg->vhost_scsi = NULL;
1707                 vs->vs_tpg[target] = NULL;
1708                 match = true;
1709                 mutex_unlock(&tpg->tv_tpg_mutex);
1710                 /*
1711                  * Release se_tpg->tpg_group.cg_item configfs dependency now
1712                  * to allow vhost-scsi WWPN se_tpg->tpg_group shutdown to occur.
1713                  */
1714                 se_tpg = &tpg->se_tpg;
1715                 target_undepend_item(&se_tpg->tpg_group.cg_item);
1716         }
1717         if (match) {
1718                 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1719                         vq = &vs->vqs[i].vq;
1720                         mutex_lock(&vq->mutex);
1721                         vhost_vq_set_backend(vq, NULL);
1722                         mutex_unlock(&vq->mutex);
1723                 }
1724                 /* Make sure cmds are not running before tearing them down. */
1725                 vhost_scsi_flush(vs);
1726
1727                 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1728                         vq = &vs->vqs[i].vq;
1729                         vhost_scsi_destroy_vq_cmds(vq);
1730                 }
1731         }
1732         /*
1733          * Act as synchronize_rcu to make sure access to
1734          * old vs->vs_tpg is finished.
1735          */
1736         vhost_scsi_flush(vs);
1737         kfree(vs->vs_tpg);
1738         vs->vs_tpg = NULL;
1739         WARN_ON(vs->vs_events_nr);
1740         mutex_unlock(&vs->dev.mutex);
1741         mutex_unlock(&vhost_scsi_mutex);
1742         return 0;
1743
1744 err_tpg:
1745         mutex_unlock(&tpg->tv_tpg_mutex);
1746 err_dev:
1747         mutex_unlock(&vs->dev.mutex);
1748         mutex_unlock(&vhost_scsi_mutex);
1749         return ret;
1750 }
1751
1752 static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features)
1753 {
1754         struct vhost_virtqueue *vq;
1755         int i;
1756
1757         if (features & ~VHOST_SCSI_FEATURES)
1758                 return -EOPNOTSUPP;
1759
1760         mutex_lock(&vs->dev.mutex);
1761         if ((features & (1 << VHOST_F_LOG_ALL)) &&
1762             !vhost_log_access_ok(&vs->dev)) {
1763                 mutex_unlock(&vs->dev.mutex);
1764                 return -EFAULT;
1765         }
1766
1767         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1768                 vq = &vs->vqs[i].vq;
1769                 mutex_lock(&vq->mutex);
1770                 vq->acked_features = features;
1771                 mutex_unlock(&vq->mutex);
1772         }
1773         mutex_unlock(&vs->dev.mutex);
1774         return 0;
1775 }
1776
1777 static int vhost_scsi_open(struct inode *inode, struct file *f)
1778 {
1779         struct vhost_scsi *vs;
1780         struct vhost_virtqueue **vqs;
1781         int r = -ENOMEM, i;
1782
1783         vs = kvzalloc(sizeof(*vs), GFP_KERNEL);
1784         if (!vs)
1785                 goto err_vs;
1786
1787         vqs = kmalloc_array(VHOST_SCSI_MAX_VQ, sizeof(*vqs), GFP_KERNEL);
1788         if (!vqs)
1789                 goto err_vqs;
1790
1791         vhost_work_init(&vs->vs_completion_work, vhost_scsi_complete_cmd_work);
1792         vhost_work_init(&vs->vs_event_work, vhost_scsi_evt_work);
1793
1794         vs->vs_events_nr = 0;
1795         vs->vs_events_missed = false;
1796
1797         vqs[VHOST_SCSI_VQ_CTL] = &vs->vqs[VHOST_SCSI_VQ_CTL].vq;
1798         vqs[VHOST_SCSI_VQ_EVT] = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1799         vs->vqs[VHOST_SCSI_VQ_CTL].vq.handle_kick = vhost_scsi_ctl_handle_kick;
1800         vs->vqs[VHOST_SCSI_VQ_EVT].vq.handle_kick = vhost_scsi_evt_handle_kick;
1801         for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++) {
1802                 vqs[i] = &vs->vqs[i].vq;
1803                 vs->vqs[i].vq.handle_kick = vhost_scsi_handle_kick;
1804         }
1805         vhost_dev_init(&vs->dev, vqs, VHOST_SCSI_MAX_VQ, UIO_MAXIOV,
1806                        VHOST_SCSI_WEIGHT, 0, true, NULL);
1807
1808         vhost_scsi_init_inflight(vs, NULL);
1809
1810         f->private_data = vs;
1811         return 0;
1812
1813 err_vqs:
1814         kvfree(vs);
1815 err_vs:
1816         return r;
1817 }
1818
1819 static int vhost_scsi_release(struct inode *inode, struct file *f)
1820 {
1821         struct vhost_scsi *vs = f->private_data;
1822         struct vhost_scsi_target t;
1823
1824         mutex_lock(&vs->dev.mutex);
1825         memcpy(t.vhost_wwpn, vs->vs_vhost_wwpn, sizeof(t.vhost_wwpn));
1826         mutex_unlock(&vs->dev.mutex);
1827         vhost_scsi_clear_endpoint(vs, &t);
1828         vhost_dev_stop(&vs->dev);
1829         vhost_dev_cleanup(&vs->dev);
1830         /* Jobs can re-queue themselves in evt kick handler. Do extra flush. */
1831         vhost_scsi_flush(vs);
1832         kfree(vs->dev.vqs);
1833         kvfree(vs);
1834         return 0;
1835 }
1836
1837 static long
1838 vhost_scsi_ioctl(struct file *f,
1839                  unsigned int ioctl,
1840                  unsigned long arg)
1841 {
1842         struct vhost_scsi *vs = f->private_data;
1843         struct vhost_scsi_target backend;
1844         void __user *argp = (void __user *)arg;
1845         u64 __user *featurep = argp;
1846         u32 __user *eventsp = argp;
1847         u32 events_missed;
1848         u64 features;
1849         int r, abi_version = VHOST_SCSI_ABI_VERSION;
1850         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1851
1852         switch (ioctl) {
1853         case VHOST_SCSI_SET_ENDPOINT:
1854                 if (copy_from_user(&backend, argp, sizeof backend))
1855                         return -EFAULT;
1856                 if (backend.reserved != 0)
1857                         return -EOPNOTSUPP;
1858
1859                 return vhost_scsi_set_endpoint(vs, &backend);
1860         case VHOST_SCSI_CLEAR_ENDPOINT:
1861                 if (copy_from_user(&backend, argp, sizeof backend))
1862                         return -EFAULT;
1863                 if (backend.reserved != 0)
1864                         return -EOPNOTSUPP;
1865
1866                 return vhost_scsi_clear_endpoint(vs, &backend);
1867         case VHOST_SCSI_GET_ABI_VERSION:
1868                 if (copy_to_user(argp, &abi_version, sizeof abi_version))
1869                         return -EFAULT;
1870                 return 0;
1871         case VHOST_SCSI_SET_EVENTS_MISSED:
1872                 if (get_user(events_missed, eventsp))
1873                         return -EFAULT;
1874                 mutex_lock(&vq->mutex);
1875                 vs->vs_events_missed = events_missed;
1876                 mutex_unlock(&vq->mutex);
1877                 return 0;
1878         case VHOST_SCSI_GET_EVENTS_MISSED:
1879                 mutex_lock(&vq->mutex);
1880                 events_missed = vs->vs_events_missed;
1881                 mutex_unlock(&vq->mutex);
1882                 if (put_user(events_missed, eventsp))
1883                         return -EFAULT;
1884                 return 0;
1885         case VHOST_GET_FEATURES:
1886                 features = VHOST_SCSI_FEATURES;
1887                 if (copy_to_user(featurep, &features, sizeof features))
1888                         return -EFAULT;
1889                 return 0;
1890         case VHOST_SET_FEATURES:
1891                 if (copy_from_user(&features, featurep, sizeof features))
1892                         return -EFAULT;
1893                 return vhost_scsi_set_features(vs, features);
1894         default:
1895                 mutex_lock(&vs->dev.mutex);
1896                 r = vhost_dev_ioctl(&vs->dev, ioctl, argp);
1897                 /* TODO: flush backend after dev ioctl. */
1898                 if (r == -ENOIOCTLCMD)
1899                         r = vhost_vring_ioctl(&vs->dev, ioctl, argp);
1900                 mutex_unlock(&vs->dev.mutex);
1901                 return r;
1902         }
1903 }
1904
1905 static const struct file_operations vhost_scsi_fops = {
1906         .owner          = THIS_MODULE,
1907         .release        = vhost_scsi_release,
1908         .unlocked_ioctl = vhost_scsi_ioctl,
1909         .compat_ioctl   = compat_ptr_ioctl,
1910         .open           = vhost_scsi_open,
1911         .llseek         = noop_llseek,
1912 };
1913
1914 static struct miscdevice vhost_scsi_misc = {
1915         MISC_DYNAMIC_MINOR,
1916         "vhost-scsi",
1917         &vhost_scsi_fops,
1918 };
1919
1920 static int __init vhost_scsi_register(void)
1921 {
1922         return misc_register(&vhost_scsi_misc);
1923 }
1924
1925 static void vhost_scsi_deregister(void)
1926 {
1927         misc_deregister(&vhost_scsi_misc);
1928 }
1929
1930 static char *vhost_scsi_dump_proto_id(struct vhost_scsi_tport *tport)
1931 {
1932         switch (tport->tport_proto_id) {
1933         case SCSI_PROTOCOL_SAS:
1934                 return "SAS";
1935         case SCSI_PROTOCOL_FCP:
1936                 return "FCP";
1937         case SCSI_PROTOCOL_ISCSI:
1938                 return "iSCSI";
1939         default:
1940                 break;
1941         }
1942
1943         return "Unknown";
1944 }
1945
1946 static void
1947 vhost_scsi_do_plug(struct vhost_scsi_tpg *tpg,
1948                   struct se_lun *lun, bool plug)
1949 {
1950
1951         struct vhost_scsi *vs = tpg->vhost_scsi;
1952         struct vhost_virtqueue *vq;
1953         u32 reason;
1954
1955         if (!vs)
1956                 return;
1957
1958         mutex_lock(&vs->dev.mutex);
1959
1960         if (plug)
1961                 reason = VIRTIO_SCSI_EVT_RESET_RESCAN;
1962         else
1963                 reason = VIRTIO_SCSI_EVT_RESET_REMOVED;
1964
1965         vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1966         mutex_lock(&vq->mutex);
1967         if (vhost_has_feature(vq, VIRTIO_SCSI_F_HOTPLUG))
1968                 vhost_scsi_send_evt(vs, tpg, lun,
1969                                    VIRTIO_SCSI_T_TRANSPORT_RESET, reason);
1970         mutex_unlock(&vq->mutex);
1971         mutex_unlock(&vs->dev.mutex);
1972 }
1973
1974 static void vhost_scsi_hotplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
1975 {
1976         vhost_scsi_do_plug(tpg, lun, true);
1977 }
1978
1979 static void vhost_scsi_hotunplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
1980 {
1981         vhost_scsi_do_plug(tpg, lun, false);
1982 }
1983
1984 static int vhost_scsi_port_link(struct se_portal_group *se_tpg,
1985                                struct se_lun *lun)
1986 {
1987         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
1988                                 struct vhost_scsi_tpg, se_tpg);
1989         struct vhost_scsi_tmf *tmf;
1990
1991         tmf = kzalloc(sizeof(*tmf), GFP_KERNEL);
1992         if (!tmf)
1993                 return -ENOMEM;
1994         INIT_LIST_HEAD(&tmf->queue_entry);
1995         vhost_work_init(&tmf->vwork, vhost_scsi_tmf_resp_work);
1996
1997         mutex_lock(&vhost_scsi_mutex);
1998
1999         mutex_lock(&tpg->tv_tpg_mutex);
2000         tpg->tv_tpg_port_count++;
2001         list_add_tail(&tmf->queue_entry, &tpg->tmf_queue);
2002         mutex_unlock(&tpg->tv_tpg_mutex);
2003
2004         vhost_scsi_hotplug(tpg, lun);
2005
2006         mutex_unlock(&vhost_scsi_mutex);
2007
2008         return 0;
2009 }
2010
2011 static void vhost_scsi_port_unlink(struct se_portal_group *se_tpg,
2012                                   struct se_lun *lun)
2013 {
2014         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2015                                 struct vhost_scsi_tpg, se_tpg);
2016         struct vhost_scsi_tmf *tmf;
2017
2018         mutex_lock(&vhost_scsi_mutex);
2019
2020         mutex_lock(&tpg->tv_tpg_mutex);
2021         tpg->tv_tpg_port_count--;
2022         tmf = list_first_entry(&tpg->tmf_queue, struct vhost_scsi_tmf,
2023                                queue_entry);
2024         list_del(&tmf->queue_entry);
2025         kfree(tmf);
2026         mutex_unlock(&tpg->tv_tpg_mutex);
2027
2028         vhost_scsi_hotunplug(tpg, lun);
2029
2030         mutex_unlock(&vhost_scsi_mutex);
2031 }
2032
2033 static ssize_t vhost_scsi_tpg_attrib_fabric_prot_type_store(
2034                 struct config_item *item, const char *page, size_t count)
2035 {
2036         struct se_portal_group *se_tpg = attrib_to_tpg(item);
2037         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2038                                 struct vhost_scsi_tpg, se_tpg);
2039         unsigned long val;
2040         int ret = kstrtoul(page, 0, &val);
2041
2042         if (ret) {
2043                 pr_err("kstrtoul() returned %d for fabric_prot_type\n", ret);
2044                 return ret;
2045         }
2046         if (val != 0 && val != 1 && val != 3) {
2047                 pr_err("Invalid vhost_scsi fabric_prot_type: %lu\n", val);
2048                 return -EINVAL;
2049         }
2050         tpg->tv_fabric_prot_type = val;
2051
2052         return count;
2053 }
2054
2055 static ssize_t vhost_scsi_tpg_attrib_fabric_prot_type_show(
2056                 struct config_item *item, char *page)
2057 {
2058         struct se_portal_group *se_tpg = attrib_to_tpg(item);
2059         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2060                                 struct vhost_scsi_tpg, se_tpg);
2061
2062         return sprintf(page, "%d\n", tpg->tv_fabric_prot_type);
2063 }
2064
2065 CONFIGFS_ATTR(vhost_scsi_tpg_attrib_, fabric_prot_type);
2066
2067 static struct configfs_attribute *vhost_scsi_tpg_attrib_attrs[] = {
2068         &vhost_scsi_tpg_attrib_attr_fabric_prot_type,
2069         NULL,
2070 };
2071
2072 static int vhost_scsi_make_nexus(struct vhost_scsi_tpg *tpg,
2073                                 const char *name)
2074 {
2075         struct vhost_scsi_nexus *tv_nexus;
2076
2077         mutex_lock(&tpg->tv_tpg_mutex);
2078         if (tpg->tpg_nexus) {
2079                 mutex_unlock(&tpg->tv_tpg_mutex);
2080                 pr_debug("tpg->tpg_nexus already exists\n");
2081                 return -EEXIST;
2082         }
2083
2084         tv_nexus = kzalloc(sizeof(*tv_nexus), GFP_KERNEL);
2085         if (!tv_nexus) {
2086                 mutex_unlock(&tpg->tv_tpg_mutex);
2087                 pr_err("Unable to allocate struct vhost_scsi_nexus\n");
2088                 return -ENOMEM;
2089         }
2090         /*
2091          * Since we are running in 'demo mode' this call with generate a
2092          * struct se_node_acl for the vhost_scsi struct se_portal_group with
2093          * the SCSI Initiator port name of the passed configfs group 'name'.
2094          */
2095         tv_nexus->tvn_se_sess = target_setup_session(&tpg->se_tpg, 0, 0,
2096                                         TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS,
2097                                         (unsigned char *)name, tv_nexus, NULL);
2098         if (IS_ERR(tv_nexus->tvn_se_sess)) {
2099                 mutex_unlock(&tpg->tv_tpg_mutex);
2100                 kfree(tv_nexus);
2101                 return -ENOMEM;
2102         }
2103         tpg->tpg_nexus = tv_nexus;
2104
2105         mutex_unlock(&tpg->tv_tpg_mutex);
2106         return 0;
2107 }
2108
2109 static int vhost_scsi_drop_nexus(struct vhost_scsi_tpg *tpg)
2110 {
2111         struct se_session *se_sess;
2112         struct vhost_scsi_nexus *tv_nexus;
2113
2114         mutex_lock(&tpg->tv_tpg_mutex);
2115         tv_nexus = tpg->tpg_nexus;
2116         if (!tv_nexus) {
2117                 mutex_unlock(&tpg->tv_tpg_mutex);
2118                 return -ENODEV;
2119         }
2120
2121         se_sess = tv_nexus->tvn_se_sess;
2122         if (!se_sess) {
2123                 mutex_unlock(&tpg->tv_tpg_mutex);
2124                 return -ENODEV;
2125         }
2126
2127         if (tpg->tv_tpg_port_count != 0) {
2128                 mutex_unlock(&tpg->tv_tpg_mutex);
2129                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
2130                         " active TPG port count: %d\n",
2131                         tpg->tv_tpg_port_count);
2132                 return -EBUSY;
2133         }
2134
2135         if (tpg->tv_tpg_vhost_count != 0) {
2136                 mutex_unlock(&tpg->tv_tpg_mutex);
2137                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
2138                         " active TPG vhost count: %d\n",
2139                         tpg->tv_tpg_vhost_count);
2140                 return -EBUSY;
2141         }
2142
2143         pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated"
2144                 " %s Initiator Port: %s\n", vhost_scsi_dump_proto_id(tpg->tport),
2145                 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
2146
2147         /*
2148          * Release the SCSI I_T Nexus to the emulated vhost Target Port
2149          */
2150         target_remove_session(se_sess);
2151         tpg->tpg_nexus = NULL;
2152         mutex_unlock(&tpg->tv_tpg_mutex);
2153
2154         kfree(tv_nexus);
2155         return 0;
2156 }
2157
2158 static ssize_t vhost_scsi_tpg_nexus_show(struct config_item *item, char *page)
2159 {
2160         struct se_portal_group *se_tpg = to_tpg(item);
2161         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2162                                 struct vhost_scsi_tpg, se_tpg);
2163         struct vhost_scsi_nexus *tv_nexus;
2164         ssize_t ret;
2165
2166         mutex_lock(&tpg->tv_tpg_mutex);
2167         tv_nexus = tpg->tpg_nexus;
2168         if (!tv_nexus) {
2169                 mutex_unlock(&tpg->tv_tpg_mutex);
2170                 return -ENODEV;
2171         }
2172         ret = snprintf(page, PAGE_SIZE, "%s\n",
2173                         tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
2174         mutex_unlock(&tpg->tv_tpg_mutex);
2175
2176         return ret;
2177 }
2178
2179 static ssize_t vhost_scsi_tpg_nexus_store(struct config_item *item,
2180                 const char *page, size_t count)
2181 {
2182         struct se_portal_group *se_tpg = to_tpg(item);
2183         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2184                                 struct vhost_scsi_tpg, se_tpg);
2185         struct vhost_scsi_tport *tport_wwn = tpg->tport;
2186         unsigned char i_port[VHOST_SCSI_NAMELEN], *ptr, *port_ptr;
2187         int ret;
2188         /*
2189          * Shutdown the active I_T nexus if 'NULL' is passed..
2190          */
2191         if (!strncmp(page, "NULL", 4)) {
2192                 ret = vhost_scsi_drop_nexus(tpg);
2193                 return (!ret) ? count : ret;
2194         }
2195         /*
2196          * Otherwise make sure the passed virtual Initiator port WWN matches
2197          * the fabric protocol_id set in vhost_scsi_make_tport(), and call
2198          * vhost_scsi_make_nexus().
2199          */
2200         if (strlen(page) >= VHOST_SCSI_NAMELEN) {
2201                 pr_err("Emulated NAA Sas Address: %s, exceeds"
2202                                 " max: %d\n", page, VHOST_SCSI_NAMELEN);
2203                 return -EINVAL;
2204         }
2205         snprintf(&i_port[0], VHOST_SCSI_NAMELEN, "%s", page);
2206
2207         ptr = strstr(i_port, "naa.");
2208         if (ptr) {
2209                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
2210                         pr_err("Passed SAS Initiator Port %s does not"
2211                                 " match target port protoid: %s\n", i_port,
2212                                 vhost_scsi_dump_proto_id(tport_wwn));
2213                         return -EINVAL;
2214                 }
2215                 port_ptr = &i_port[0];
2216                 goto check_newline;
2217         }
2218         ptr = strstr(i_port, "fc.");
2219         if (ptr) {
2220                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
2221                         pr_err("Passed FCP Initiator Port %s does not"
2222                                 " match target port protoid: %s\n", i_port,
2223                                 vhost_scsi_dump_proto_id(tport_wwn));
2224                         return -EINVAL;
2225                 }
2226                 port_ptr = &i_port[3]; /* Skip over "fc." */
2227                 goto check_newline;
2228         }
2229         ptr = strstr(i_port, "iqn.");
2230         if (ptr) {
2231                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
2232                         pr_err("Passed iSCSI Initiator Port %s does not"
2233                                 " match target port protoid: %s\n", i_port,
2234                                 vhost_scsi_dump_proto_id(tport_wwn));
2235                         return -EINVAL;
2236                 }
2237                 port_ptr = &i_port[0];
2238                 goto check_newline;
2239         }
2240         pr_err("Unable to locate prefix for emulated Initiator Port:"
2241                         " %s\n", i_port);
2242         return -EINVAL;
2243         /*
2244          * Clear any trailing newline for the NAA WWN
2245          */
2246 check_newline:
2247         if (i_port[strlen(i_port)-1] == '\n')
2248                 i_port[strlen(i_port)-1] = '\0';
2249
2250         ret = vhost_scsi_make_nexus(tpg, port_ptr);
2251         if (ret < 0)
2252                 return ret;
2253
2254         return count;
2255 }
2256
2257 CONFIGFS_ATTR(vhost_scsi_tpg_, nexus);
2258
2259 static struct configfs_attribute *vhost_scsi_tpg_attrs[] = {
2260         &vhost_scsi_tpg_attr_nexus,
2261         NULL,
2262 };
2263
2264 static struct se_portal_group *
2265 vhost_scsi_make_tpg(struct se_wwn *wwn, const char *name)
2266 {
2267         struct vhost_scsi_tport *tport = container_of(wwn,
2268                         struct vhost_scsi_tport, tport_wwn);
2269
2270         struct vhost_scsi_tpg *tpg;
2271         u16 tpgt;
2272         int ret;
2273
2274         if (strstr(name, "tpgt_") != name)
2275                 return ERR_PTR(-EINVAL);
2276         if (kstrtou16(name + 5, 10, &tpgt) || tpgt >= VHOST_SCSI_MAX_TARGET)
2277                 return ERR_PTR(-EINVAL);
2278
2279         tpg = kzalloc(sizeof(*tpg), GFP_KERNEL);
2280         if (!tpg) {
2281                 pr_err("Unable to allocate struct vhost_scsi_tpg");
2282                 return ERR_PTR(-ENOMEM);
2283         }
2284         mutex_init(&tpg->tv_tpg_mutex);
2285         INIT_LIST_HEAD(&tpg->tv_tpg_list);
2286         INIT_LIST_HEAD(&tpg->tmf_queue);
2287         tpg->tport = tport;
2288         tpg->tport_tpgt = tpgt;
2289
2290         ret = core_tpg_register(wwn, &tpg->se_tpg, tport->tport_proto_id);
2291         if (ret < 0) {
2292                 kfree(tpg);
2293                 return NULL;
2294         }
2295         mutex_lock(&vhost_scsi_mutex);
2296         list_add_tail(&tpg->tv_tpg_list, &vhost_scsi_list);
2297         mutex_unlock(&vhost_scsi_mutex);
2298
2299         return &tpg->se_tpg;
2300 }
2301
2302 static void vhost_scsi_drop_tpg(struct se_portal_group *se_tpg)
2303 {
2304         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2305                                 struct vhost_scsi_tpg, se_tpg);
2306
2307         mutex_lock(&vhost_scsi_mutex);
2308         list_del(&tpg->tv_tpg_list);
2309         mutex_unlock(&vhost_scsi_mutex);
2310         /*
2311          * Release the virtual I_T Nexus for this vhost TPG
2312          */
2313         vhost_scsi_drop_nexus(tpg);
2314         /*
2315          * Deregister the se_tpg from TCM..
2316          */
2317         core_tpg_deregister(se_tpg);
2318         kfree(tpg);
2319 }
2320
2321 static struct se_wwn *
2322 vhost_scsi_make_tport(struct target_fabric_configfs *tf,
2323                      struct config_group *group,
2324                      const char *name)
2325 {
2326         struct vhost_scsi_tport *tport;
2327         char *ptr;
2328         u64 wwpn = 0;
2329         int off = 0;
2330
2331         /* if (vhost_scsi_parse_wwn(name, &wwpn, 1) < 0)
2332                 return ERR_PTR(-EINVAL); */
2333
2334         tport = kzalloc(sizeof(*tport), GFP_KERNEL);
2335         if (!tport) {
2336                 pr_err("Unable to allocate struct vhost_scsi_tport");
2337                 return ERR_PTR(-ENOMEM);
2338         }
2339         tport->tport_wwpn = wwpn;
2340         /*
2341          * Determine the emulated Protocol Identifier and Target Port Name
2342          * based on the incoming configfs directory name.
2343          */
2344         ptr = strstr(name, "naa.");
2345         if (ptr) {
2346                 tport->tport_proto_id = SCSI_PROTOCOL_SAS;
2347                 goto check_len;
2348         }
2349         ptr = strstr(name, "fc.");
2350         if (ptr) {
2351                 tport->tport_proto_id = SCSI_PROTOCOL_FCP;
2352                 off = 3; /* Skip over "fc." */
2353                 goto check_len;
2354         }
2355         ptr = strstr(name, "iqn.");
2356         if (ptr) {
2357                 tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
2358                 goto check_len;
2359         }
2360
2361         pr_err("Unable to locate prefix for emulated Target Port:"
2362                         " %s\n", name);
2363         kfree(tport);
2364         return ERR_PTR(-EINVAL);
2365
2366 check_len:
2367         if (strlen(name) >= VHOST_SCSI_NAMELEN) {
2368                 pr_err("Emulated %s Address: %s, exceeds"
2369                         " max: %d\n", name, vhost_scsi_dump_proto_id(tport),
2370                         VHOST_SCSI_NAMELEN);
2371                 kfree(tport);
2372                 return ERR_PTR(-EINVAL);
2373         }
2374         snprintf(&tport->tport_name[0], VHOST_SCSI_NAMELEN, "%s", &name[off]);
2375
2376         pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target"
2377                 " %s Address: %s\n", vhost_scsi_dump_proto_id(tport), name);
2378
2379         return &tport->tport_wwn;
2380 }
2381
2382 static void vhost_scsi_drop_tport(struct se_wwn *wwn)
2383 {
2384         struct vhost_scsi_tport *tport = container_of(wwn,
2385                                 struct vhost_scsi_tport, tport_wwn);
2386
2387         pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target"
2388                 " %s Address: %s\n", vhost_scsi_dump_proto_id(tport),
2389                 tport->tport_name);
2390
2391         kfree(tport);
2392 }
2393
2394 static ssize_t
2395 vhost_scsi_wwn_version_show(struct config_item *item, char *page)
2396 {
2397         return sprintf(page, "TCM_VHOST fabric module %s on %s/%s"
2398                 "on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
2399                 utsname()->machine);
2400 }
2401
2402 CONFIGFS_ATTR_RO(vhost_scsi_wwn_, version);
2403
2404 static struct configfs_attribute *vhost_scsi_wwn_attrs[] = {
2405         &vhost_scsi_wwn_attr_version,
2406         NULL,
2407 };
2408
2409 static const struct target_core_fabric_ops vhost_scsi_ops = {
2410         .module                         = THIS_MODULE,
2411         .fabric_name                    = "vhost",
2412         .max_data_sg_nents              = VHOST_SCSI_PREALLOC_SGLS,
2413         .tpg_get_wwn                    = vhost_scsi_get_fabric_wwn,
2414         .tpg_get_tag                    = vhost_scsi_get_tpgt,
2415         .tpg_check_demo_mode            = vhost_scsi_check_true,
2416         .tpg_check_demo_mode_cache      = vhost_scsi_check_true,
2417         .tpg_check_demo_mode_write_protect = vhost_scsi_check_false,
2418         .tpg_check_prod_mode_write_protect = vhost_scsi_check_false,
2419         .tpg_check_prot_fabric_only     = vhost_scsi_check_prot_fabric_only,
2420         .tpg_get_inst_index             = vhost_scsi_tpg_get_inst_index,
2421         .release_cmd                    = vhost_scsi_release_cmd,
2422         .check_stop_free                = vhost_scsi_check_stop_free,
2423         .sess_get_index                 = vhost_scsi_sess_get_index,
2424         .sess_get_initiator_sid         = NULL,
2425         .write_pending                  = vhost_scsi_write_pending,
2426         .set_default_node_attributes    = vhost_scsi_set_default_node_attrs,
2427         .get_cmd_state                  = vhost_scsi_get_cmd_state,
2428         .queue_data_in                  = vhost_scsi_queue_data_in,
2429         .queue_status                   = vhost_scsi_queue_status,
2430         .queue_tm_rsp                   = vhost_scsi_queue_tm_rsp,
2431         .aborted_task                   = vhost_scsi_aborted_task,
2432         /*
2433          * Setup callers for generic logic in target_core_fabric_configfs.c
2434          */
2435         .fabric_make_wwn                = vhost_scsi_make_tport,
2436         .fabric_drop_wwn                = vhost_scsi_drop_tport,
2437         .fabric_make_tpg                = vhost_scsi_make_tpg,
2438         .fabric_drop_tpg                = vhost_scsi_drop_tpg,
2439         .fabric_post_link               = vhost_scsi_port_link,
2440         .fabric_pre_unlink              = vhost_scsi_port_unlink,
2441
2442         .tfc_wwn_attrs                  = vhost_scsi_wwn_attrs,
2443         .tfc_tpg_base_attrs             = vhost_scsi_tpg_attrs,
2444         .tfc_tpg_attrib_attrs           = vhost_scsi_tpg_attrib_attrs,
2445 };
2446
2447 static int __init vhost_scsi_init(void)
2448 {
2449         int ret = -ENOMEM;
2450
2451         pr_debug("TCM_VHOST fabric module %s on %s/%s"
2452                 " on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
2453                 utsname()->machine);
2454
2455         ret = vhost_scsi_register();
2456         if (ret < 0)
2457                 goto out;
2458
2459         ret = target_register_template(&vhost_scsi_ops);
2460         if (ret < 0)
2461                 goto out_vhost_scsi_deregister;
2462
2463         return 0;
2464
2465 out_vhost_scsi_deregister:
2466         vhost_scsi_deregister();
2467 out:
2468         return ret;
2469 };
2470
2471 static void vhost_scsi_exit(void)
2472 {
2473         target_unregister_template(&vhost_scsi_ops);
2474         vhost_scsi_deregister();
2475 };
2476
2477 MODULE_DESCRIPTION("VHOST_SCSI series fabric driver");
2478 MODULE_ALIAS("tcm_vhost");
2479 MODULE_LICENSE("GPL");
2480 module_init(vhost_scsi_init);
2481 module_exit(vhost_scsi_exit);