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 };
 129
 130 struct vhost_scsi_tport {
 131         /* SCSI protocol the tport is providing */
 132         u8 tport_proto_id;
 133         /* Binary World Wide unique Port Name for Vhost Target port */
 134         u64 tport_wwpn;
 135         /* ASCII formatted WWPN for Vhost Target port */
 136         char tport_name[VHOST_SCSI_NAMELEN];
 137         /* Returned by vhost_scsi_make_tport() */
 138         struct se_wwn tport_wwn;
 139 };
 140
 141 struct vhost_scsi_evt {
 142         /* event to be sent to guest */
 143         struct virtio_scsi_event event;
 144         /* event list, serviced from vhost worker thread */
 145         struct llist_node list;
 146 };
 147
 148 enum {
 149         VHOST_SCSI_VQ_CTL = 0,
 150         VHOST_SCSI_VQ_EVT = 1,
 151         VHOST_SCSI_VQ_IO = 2,
 152 };
 153
 154 /* Note: can't set VIRTIO_F_VERSION_1 yet, since that implies ANY_LAYOUT. */
 155 enum {
 156         VHOST_SCSI_FEATURES = VHOST_FEATURES | (1ULL << VIRTIO_SCSI_F_HOTPLUG) |
 157                                                (1ULL << VIRTIO_SCSI_F_T10_PI)
 158 };
 159
 160 #define VHOST_SCSI_MAX_TARGET   256
 161 #define VHOST_SCSI_MAX_IO_VQ    1024
 162 #define VHOST_SCSI_MAX_EVENT    128
 163
 164 static unsigned vhost_scsi_max_io_vqs = 128;
 165 module_param_named(max_io_vqs, vhost_scsi_max_io_vqs, uint, 0644);
 166 MODULE_PARM_DESC(max_io_vqs, "Set the max number of IO virtqueues a vhost scsi device can support. The default is 128. The max is 1024.");
 167
 168 struct vhost_scsi_virtqueue {
 169         struct vhost_virtqueue vq;
 170         /*
 171          * Reference counting for inflight reqs, used for flush operation. At
 172          * each time, one reference tracks new commands submitted, while we
 173          * wait for another one to reach 0.
 174          */
 175         struct vhost_scsi_inflight inflights[2];
 176         /*
 177          * Indicate current inflight in use, protected by vq->mutex.
 178          * Writers must also take dev mutex and flush under it.
 179          */
 180         int inflight_idx;
 181         struct vhost_scsi_cmd *scsi_cmds;
 182         struct sbitmap scsi_tags;
 183         int max_cmds;
 184 };
 185
 186 struct vhost_scsi {
 187         /* Protected by vhost_scsi->dev.mutex */
 188         struct vhost_scsi_tpg **vs_tpg;
 189         char vs_vhost_wwpn[TRANSPORT_IQN_LEN];
 190
 191         struct vhost_dev dev;
 192         struct vhost_scsi_virtqueue *vqs;
 193         unsigned long *compl_bitmap;
 194         struct vhost_scsi_inflight **old_inflight;
 195
 196         struct vhost_work vs_completion_work; /* cmd completion work item */
 197         struct llist_head vs_completion_list; /* cmd completion queue */
 198
 199         struct vhost_work vs_event_work; /* evt injection work item */
 200         struct llist_head vs_event_list; /* evt injection queue */
 201
 202         bool vs_events_missed; /* any missed events, protected by vq->mutex */
 203         int vs_events_nr; /* num of pending events, protected by vq->mutex */
 204 };
 205
 206 struct vhost_scsi_tmf {
 207         struct vhost_work vwork;
 208         struct vhost_scsi *vhost;
 209         struct vhost_scsi_virtqueue *svq;
 210
 211         struct se_cmd se_cmd;
 212         u8 scsi_resp;
 213         struct vhost_scsi_inflight *inflight;
 214         struct iovec resp_iov;
 215         int in_iovs;
 216         int vq_desc;
 217 };
 218
 219 /*
 220  * Context for processing request and control queue operations.
 221  */
 222 struct vhost_scsi_ctx {
 223         int head;
 224         unsigned int out, in;
 225         size_t req_size, rsp_size;
 226         size_t out_size, in_size;
 227         u8 *target, *lunp;
 228         void *req;
 229         struct iov_iter out_iter;
 230 };
 231
 232 /* Global spinlock to protect vhost_scsi TPG list for vhost IOCTL access */
 233 static DEFINE_MUTEX(vhost_scsi_mutex);
 234 static LIST_HEAD(vhost_scsi_list);
 235
 236 static void vhost_scsi_done_inflight(struct kref *kref)
 237 {
 238         struct vhost_scsi_inflight *inflight;
 239
 240         inflight = container_of(kref, struct vhost_scsi_inflight, kref);
 241         complete(&inflight->comp);
 242 }
 243
 244 static void vhost_scsi_init_inflight(struct vhost_scsi *vs,
 245                                     struct vhost_scsi_inflight *old_inflight[])
 246 {
 247         struct vhost_scsi_inflight *new_inflight;
 248         struct vhost_virtqueue *vq;
 249         int idx, i;
 250
 251         for (i = 0; i < vs->dev.nvqs;  i++) {
 252                 vq = &vs->vqs[i].vq;
 253
 254                 mutex_lock(&vq->mutex);
 255
 256                 /* store old infight */
 257                 idx = vs->vqs[i].inflight_idx;
 258                 if (old_inflight)
 259                         old_inflight[i] = &vs->vqs[i].inflights[idx];
 260
 261                 /* setup new infight */
 262                 vs->vqs[i].inflight_idx = idx ^ 1;
 263                 new_inflight = &vs->vqs[i].inflights[idx ^ 1];
 264                 kref_init(&new_inflight->kref);
 265                 init_completion(&new_inflight->comp);
 266
 267                 mutex_unlock(&vq->mutex);
 268         }
 269 }
 270
 271 static struct vhost_scsi_inflight *
 272 vhost_scsi_get_inflight(struct vhost_virtqueue *vq)
 273 {
 274         struct vhost_scsi_inflight *inflight;
 275         struct vhost_scsi_virtqueue *svq;
 276
 277         svq = container_of(vq, struct vhost_scsi_virtqueue, vq);
 278         inflight = &svq->inflights[svq->inflight_idx];
 279         kref_get(&inflight->kref);
 280
 281         return inflight;
 282 }
 283
 284 static void vhost_scsi_put_inflight(struct vhost_scsi_inflight *inflight)
 285 {
 286         kref_put(&inflight->kref, vhost_scsi_done_inflight);
 287 }
 288
 289 static int vhost_scsi_check_true(struct se_portal_group *se_tpg)
 290 {
 291         return 1;
 292 }
 293
 294 static char *vhost_scsi_get_fabric_wwn(struct se_portal_group *se_tpg)
 295 {
 296         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 297                                 struct vhost_scsi_tpg, se_tpg);
 298         struct vhost_scsi_tport *tport = tpg->tport;
 299
 300         return &tport->tport_name[0];
 301 }
 302
 303 static u16 vhost_scsi_get_tpgt(struct se_portal_group *se_tpg)
 304 {
 305         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 306                                 struct vhost_scsi_tpg, se_tpg);
 307         return tpg->tport_tpgt;
 308 }
 309
 310 static int vhost_scsi_check_prot_fabric_only(struct se_portal_group *se_tpg)
 311 {
 312         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 313                                 struct vhost_scsi_tpg, se_tpg);
 314
 315         return tpg->tv_fabric_prot_type;
 316 }
 317
 318 static void vhost_scsi_release_cmd_res(struct se_cmd *se_cmd)
 319 {
 320         struct vhost_scsi_cmd *tv_cmd = container_of(se_cmd,
 321                                 struct vhost_scsi_cmd, tvc_se_cmd);
 322         struct vhost_scsi_virtqueue *svq = container_of(tv_cmd->tvc_vq,
 323                                 struct vhost_scsi_virtqueue, vq);
 324         struct vhost_scsi_inflight *inflight = tv_cmd->inflight;
 325         int i;
 326
 327         if (tv_cmd->tvc_sgl_count) {
 328                 for (i = 0; i < tv_cmd->tvc_sgl_count; i++)
 329                         put_page(sg_page(&tv_cmd->tvc_sgl[i]));
 330         }
 331         if (tv_cmd->tvc_prot_sgl_count) {
 332                 for (i = 0; i < tv_cmd->tvc_prot_sgl_count; i++)
 333                         put_page(sg_page(&tv_cmd->tvc_prot_sgl[i]));
 334         }
 335
 336         sbitmap_clear_bit(&svq->scsi_tags, se_cmd->map_tag);
 337         vhost_scsi_put_inflight(inflight);
 338 }
 339
 340 static void vhost_scsi_release_tmf_res(struct vhost_scsi_tmf *tmf)
 341 {
 342         struct vhost_scsi_inflight *inflight = tmf->inflight;
 343
 344         kfree(tmf);
 345         vhost_scsi_put_inflight(inflight);
 346 }
 347
 348 static void vhost_scsi_release_cmd(struct se_cmd *se_cmd)
 349 {
 350         if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB) {
 351                 struct vhost_scsi_tmf *tmf = container_of(se_cmd,
 352                                         struct vhost_scsi_tmf, se_cmd);
 353
 354                 vhost_work_queue(&tmf->vhost->dev, &tmf->vwork);
 355         } else {
 356                 struct vhost_scsi_cmd *cmd = container_of(se_cmd,
 357                                         struct vhost_scsi_cmd, tvc_se_cmd);
 358                 struct vhost_scsi *vs = cmd->tvc_vhost;
 359
 360                 llist_add(&cmd->tvc_completion_list, &vs->vs_completion_list);
 361                 vhost_work_queue(&vs->dev, &vs->vs_completion_work);
 362         }
 363 }
 364
 365 static int vhost_scsi_write_pending(struct se_cmd *se_cmd)
 366 {
 367         /* Go ahead and process the write immediately */
 368         target_execute_cmd(se_cmd);
 369         return 0;
 370 }
 371
 372 static int vhost_scsi_queue_data_in(struct se_cmd *se_cmd)
 373 {
 374         transport_generic_free_cmd(se_cmd, 0);
 375         return 0;
 376 }
 377
 378 static int vhost_scsi_queue_status(struct se_cmd *se_cmd)
 379 {
 380         transport_generic_free_cmd(se_cmd, 0);
 381         return 0;
 382 }
 383
 384 static void vhost_scsi_queue_tm_rsp(struct se_cmd *se_cmd)
 385 {
 386         struct vhost_scsi_tmf *tmf = container_of(se_cmd, struct vhost_scsi_tmf,
 387                                                   se_cmd);
 388
 389         tmf->scsi_resp = se_cmd->se_tmr_req->response;
 390         transport_generic_free_cmd(&tmf->se_cmd, 0);
 391 }
 392
 393 static void vhost_scsi_aborted_task(struct se_cmd *se_cmd)
 394 {
 395         return;
 396 }
 397
 398 static void vhost_scsi_free_evt(struct vhost_scsi *vs, struct vhost_scsi_evt *evt)
 399 {
 400         vs->vs_events_nr--;
 401         kfree(evt);
 402 }
 403
 404 static struct vhost_scsi_evt *
 405 vhost_scsi_allocate_evt(struct vhost_scsi *vs,
 406                        u32 event, u32 reason)
 407 {
 408         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 409         struct vhost_scsi_evt *evt;
 410
 411         if (vs->vs_events_nr > VHOST_SCSI_MAX_EVENT) {
 412                 vs->vs_events_missed = true;
 413                 return NULL;
 414         }
 415
 416         evt = kzalloc(sizeof(*evt), GFP_KERNEL);
 417         if (!evt) {
 418                 vq_err(vq, "Failed to allocate vhost_scsi_evt\n");
 419                 vs->vs_events_missed = true;
 420                 return NULL;
 421         }
 422
 423         evt->event.event = cpu_to_vhost32(vq, event);
 424         evt->event.reason = cpu_to_vhost32(vq, reason);
 425         vs->vs_events_nr++;
 426
 427         return evt;
 428 }
 429
 430 static int vhost_scsi_check_stop_free(struct se_cmd *se_cmd)
 431 {
 432         return target_put_sess_cmd(se_cmd);
 433 }
 434
 435 static void
 436 vhost_scsi_do_evt_work(struct vhost_scsi *vs, struct vhost_scsi_evt *evt)
 437 {
 438         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 439         struct virtio_scsi_event *event = &evt->event;
 440         struct virtio_scsi_event __user *eventp;
 441         unsigned out, in;
 442         int head, ret;
 443
 444         if (!vhost_vq_get_backend(vq)) {
 445                 vs->vs_events_missed = true;
 446                 return;
 447         }
 448
 449 again:
 450         vhost_disable_notify(&vs->dev, vq);
 451         head = vhost_get_vq_desc(vq, vq->iov,
 452                         ARRAY_SIZE(vq->iov), &out, &in,
 453                         NULL, NULL);
 454         if (head < 0) {
 455                 vs->vs_events_missed = true;
 456                 return;
 457         }
 458         if (head == vq->num) {
 459                 if (vhost_enable_notify(&vs->dev, vq))
 460                         goto again;
 461                 vs->vs_events_missed = true;
 462                 return;
 463         }
 464
 465         if ((vq->iov[out].iov_len != sizeof(struct virtio_scsi_event))) {
 466                 vq_err(vq, "Expecting virtio_scsi_event, got %zu bytes\n",
 467                                 vq->iov[out].iov_len);
 468                 vs->vs_events_missed = true;
 469                 return;
 470         }
 471
 472         if (vs->vs_events_missed) {
 473                 event->event |= cpu_to_vhost32(vq, VIRTIO_SCSI_T_EVENTS_MISSED);
 474                 vs->vs_events_missed = false;
 475         }
 476
 477         eventp = vq->iov[out].iov_base;
 478         ret = __copy_to_user(eventp, event, sizeof(*event));
 479         if (!ret)
 480                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 481         else
 482                 vq_err(vq, "Faulted on vhost_scsi_send_event\n");
 483 }
 484
 485 static void vhost_scsi_evt_work(struct vhost_work *work)
 486 {
 487         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 488                                         vs_event_work);
 489         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 490         struct vhost_scsi_evt *evt, *t;
 491         struct llist_node *llnode;
 492
 493         mutex_lock(&vq->mutex);
 494         llnode = llist_del_all(&vs->vs_event_list);
 495         llist_for_each_entry_safe(evt, t, llnode, list) {
 496                 vhost_scsi_do_evt_work(vs, evt);
 497                 vhost_scsi_free_evt(vs, evt);
 498         }
 499         mutex_unlock(&vq->mutex);
 500 }
 501
 502 /* Fill in status and signal that we are done processing this command
 503  *
 504  * This is scheduled in the vhost work queue so we are called with the owner
 505  * process mm and can access the vring.
 506  */
 507 static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
 508 {
 509         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 510                                         vs_completion_work);
 511         struct virtio_scsi_cmd_resp v_rsp;
 512         struct vhost_scsi_cmd *cmd, *t;
 513         struct llist_node *llnode;
 514         struct se_cmd *se_cmd;
 515         struct iov_iter iov_iter;
 516         int ret, vq;
 517
 518         bitmap_zero(vs->compl_bitmap, vs->dev.nvqs);
 519         llnode = llist_del_all(&vs->vs_completion_list);
 520         llist_for_each_entry_safe(cmd, t, llnode, tvc_completion_list) {
 521                 se_cmd = &cmd->tvc_se_cmd;
 522
 523                 pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__,
 524                         cmd, se_cmd->residual_count, se_cmd->scsi_status);
 525
 526                 memset(&v_rsp, 0, sizeof(v_rsp));
 527                 v_rsp.resid = cpu_to_vhost32(cmd->tvc_vq, se_cmd->residual_count);
 528                 /* TODO is status_qualifier field needed? */
 529                 v_rsp.status = se_cmd->scsi_status;
 530                 v_rsp.sense_len = cpu_to_vhost32(cmd->tvc_vq,
 531                                                  se_cmd->scsi_sense_length);
 532                 memcpy(v_rsp.sense, cmd->tvc_sense_buf,
 533                        se_cmd->scsi_sense_length);
 534
 535                 iov_iter_init(&iov_iter, ITER_DEST, cmd->tvc_resp_iov,
 536                               cmd->tvc_in_iovs, sizeof(v_rsp));
 537                 ret = copy_to_iter(&v_rsp, sizeof(v_rsp), &iov_iter);
 538                 if (likely(ret == sizeof(v_rsp))) {
 539                         struct vhost_scsi_virtqueue *q;
 540                         vhost_add_used(cmd->tvc_vq, cmd->tvc_vq_desc, 0);
 541                         q = container_of(cmd->tvc_vq, struct vhost_scsi_virtqueue, vq);
 542                         vq = q - vs->vqs;
 543                         __set_bit(vq, vs->compl_bitmap);
 544                 } else
 545                         pr_err("Faulted on virtio_scsi_cmd_resp\n");
 546
 547                 vhost_scsi_release_cmd_res(se_cmd);
 548         }
 549
 550         vq = -1;
 551         while ((vq = find_next_bit(vs->compl_bitmap, vs->dev.nvqs, vq + 1))
 552                 < vs->dev.nvqs)
 553                 vhost_signal(&vs->dev, &vs->vqs[vq].vq);
 554 }
 555
 556 static struct vhost_scsi_cmd *
 557 vhost_scsi_get_cmd(struct vhost_virtqueue *vq, struct vhost_scsi_tpg *tpg,
 558                    unsigned char *cdb, u64 scsi_tag, u16 lun, u8 task_attr,
 559                    u32 exp_data_len, int data_direction)
 560 {
 561         struct vhost_scsi_virtqueue *svq = container_of(vq,
 562                                         struct vhost_scsi_virtqueue, vq);
 563         struct vhost_scsi_cmd *cmd;
 564         struct vhost_scsi_nexus *tv_nexus;
 565         struct scatterlist *sg, *prot_sg;
 566         struct iovec *tvc_resp_iov;
 567         struct page **pages;
 568         int tag;
 569
 570         tv_nexus = tpg->tpg_nexus;
 571         if (!tv_nexus) {
 572                 pr_err("Unable to locate active struct vhost_scsi_nexus\n");
 573                 return ERR_PTR(-EIO);
 574         }
 575
 576         tag = sbitmap_get(&svq->scsi_tags);
 577         if (tag < 0) {
 578                 pr_err("Unable to obtain tag for vhost_scsi_cmd\n");
 579                 return ERR_PTR(-ENOMEM);
 580         }
 581
 582         cmd = &svq->scsi_cmds[tag];
 583         sg = cmd->tvc_sgl;
 584         prot_sg = cmd->tvc_prot_sgl;
 585         pages = cmd->tvc_upages;
 586         tvc_resp_iov = cmd->tvc_resp_iov;
 587         memset(cmd, 0, sizeof(*cmd));
 588         cmd->tvc_sgl = sg;
 589         cmd->tvc_prot_sgl = prot_sg;
 590         cmd->tvc_upages = pages;
 591         cmd->tvc_se_cmd.map_tag = tag;
 592         cmd->tvc_tag = scsi_tag;
 593         cmd->tvc_lun = lun;
 594         cmd->tvc_task_attr = task_attr;
 595         cmd->tvc_exp_data_len = exp_data_len;
 596         cmd->tvc_data_direction = data_direction;
 597         cmd->tvc_nexus = tv_nexus;
 598         cmd->inflight = vhost_scsi_get_inflight(vq);
 599         cmd->tvc_resp_iov = tvc_resp_iov;
 600
 601         memcpy(cmd->tvc_cdb, cdb, VHOST_SCSI_MAX_CDB_SIZE);
 602
 603         return cmd;
 604 }
 605
 606 /*
 607  * Map a user memory range into a scatterlist
 608  *
 609  * Returns the number of scatterlist entries used or -errno on error.
 610  */
 611 static int
 612 vhost_scsi_map_to_sgl(struct vhost_scsi_cmd *cmd,
 613                       struct iov_iter *iter,
 614                       struct scatterlist *sgl,
 615                       bool write)
 616 {
 617         struct page **pages = cmd->tvc_upages;
 618         struct scatterlist *sg = sgl;
 619         ssize_t bytes;
 620         size_t offset;
 621         unsigned int npages = 0;
 622
 623         bytes = iov_iter_get_pages2(iter, pages, LONG_MAX,
 624                                 VHOST_SCSI_PREALLOC_UPAGES, &offset);
 625         /* No pages were pinned */
 626         if (bytes <= 0)
 627                 return bytes < 0 ? bytes : -EFAULT;
 628
 629         while (bytes) {
 630                 unsigned n = min_t(unsigned, PAGE_SIZE - offset, bytes);
 631                 sg_set_page(sg++, pages[npages++], n, offset);
 632                 bytes -= n;
 633                 offset = 0;
 634         }
 635         return npages;
 636 }
 637
 638 static int
 639 vhost_scsi_calc_sgls(struct iov_iter *iter, size_t bytes, int max_sgls)
 640 {
 641         int sgl_count = 0;
 642
 643         if (!iter || !iter_iov(iter)) {
 644                 pr_err("%s: iter->iov is NULL, but expected bytes: %zu"
 645                        " present\n", __func__, bytes);
 646                 return -EINVAL;
 647         }
 648
 649         sgl_count = iov_iter_npages(iter, 0xffff);
 650         if (sgl_count > max_sgls) {
 651                 pr_err("%s: requested sgl_count: %d exceeds pre-allocated"
 652                        " max_sgls: %d\n", __func__, sgl_count, max_sgls);
 653                 return -EINVAL;
 654         }
 655         return sgl_count;
 656 }
 657
 658 static int
 659 vhost_scsi_iov_to_sgl(struct vhost_scsi_cmd *cmd, bool write,
 660                       struct iov_iter *iter,
 661                       struct scatterlist *sg, int sg_count)
 662 {
 663         struct scatterlist *p = sg;
 664         int ret;
 665
 666         while (iov_iter_count(iter)) {
 667                 ret = vhost_scsi_map_to_sgl(cmd, iter, sg, write);
 668                 if (ret < 0) {
 669                         while (p < sg) {
 670                                 struct page *page = sg_page(p++);
 671                                 if (page)
 672                                         put_page(page);
 673                         }
 674                         return ret;
 675                 }
 676                 sg += ret;
 677         }
 678         return 0;
 679 }
 680
 681 static int
 682 vhost_scsi_mapal(struct vhost_scsi_cmd *cmd,
 683                  size_t prot_bytes, struct iov_iter *prot_iter,
 684                  size_t data_bytes, struct iov_iter *data_iter)
 685 {
 686         int sgl_count, ret;
 687         bool write = (cmd->tvc_data_direction == DMA_FROM_DEVICE);
 688
 689         if (prot_bytes) {
 690                 sgl_count = vhost_scsi_calc_sgls(prot_iter, prot_bytes,
 691                                                  VHOST_SCSI_PREALLOC_PROT_SGLS);
 692                 if (sgl_count < 0)
 693                         return sgl_count;
 694
 695                 sg_init_table(cmd->tvc_prot_sgl, sgl_count);
 696                 cmd->tvc_prot_sgl_count = sgl_count;
 697                 pr_debug("%s prot_sg %p prot_sgl_count %u\n", __func__,
 698                          cmd->tvc_prot_sgl, cmd->tvc_prot_sgl_count);
 699
 700                 ret = vhost_scsi_iov_to_sgl(cmd, write, prot_iter,
 701                                             cmd->tvc_prot_sgl,
 702                                             cmd->tvc_prot_sgl_count);
 703                 if (ret < 0) {
 704                         cmd->tvc_prot_sgl_count = 0;
 705                         return ret;
 706                 }
 707         }
 708         sgl_count = vhost_scsi_calc_sgls(data_iter, data_bytes,
 709                                          VHOST_SCSI_PREALLOC_SGLS);
 710         if (sgl_count < 0)
 711                 return sgl_count;
 712
 713         sg_init_table(cmd->tvc_sgl, sgl_count);
 714         cmd->tvc_sgl_count = sgl_count;
 715         pr_debug("%s data_sg %p data_sgl_count %u\n", __func__,
 716                   cmd->tvc_sgl, cmd->tvc_sgl_count);
 717
 718         ret = vhost_scsi_iov_to_sgl(cmd, write, data_iter,
 719                                     cmd->tvc_sgl, cmd->tvc_sgl_count);
 720         if (ret < 0) {
 721                 cmd->tvc_sgl_count = 0;
 722                 return ret;
 723         }
 724         return 0;
 725 }
 726
 727 static int vhost_scsi_to_tcm_attr(int attr)
 728 {
 729         switch (attr) {
 730         case VIRTIO_SCSI_S_SIMPLE:
 731                 return TCM_SIMPLE_TAG;
 732         case VIRTIO_SCSI_S_ORDERED:
 733                 return TCM_ORDERED_TAG;
 734         case VIRTIO_SCSI_S_HEAD:
 735                 return TCM_HEAD_TAG;
 736         case VIRTIO_SCSI_S_ACA:
 737                 return TCM_ACA_TAG;
 738         default:
 739                 break;
 740         }
 741         return TCM_SIMPLE_TAG;
 742 }
 743
 744 static void vhost_scsi_target_queue_cmd(struct vhost_scsi_cmd *cmd)
 745 {
 746         struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
 747         struct vhost_scsi_nexus *tv_nexus;
 748         struct scatterlist *sg_ptr, *sg_prot_ptr = NULL;
 749
 750         /* FIXME: BIDI operation */
 751         if (cmd->tvc_sgl_count) {
 752                 sg_ptr = cmd->tvc_sgl;
 753
 754                 if (cmd->tvc_prot_sgl_count)
 755                         sg_prot_ptr = cmd->tvc_prot_sgl;
 756                 else
 757                         se_cmd->prot_pto = true;
 758         } else {
 759                 sg_ptr = NULL;
 760         }
 761         tv_nexus = cmd->tvc_nexus;
 762
 763         se_cmd->tag = 0;
 764         target_init_cmd(se_cmd, tv_nexus->tvn_se_sess, &cmd->tvc_sense_buf[0],
 765                         cmd->tvc_lun, cmd->tvc_exp_data_len,
 766                         vhost_scsi_to_tcm_attr(cmd->tvc_task_attr),
 767                         cmd->tvc_data_direction, TARGET_SCF_ACK_KREF);
 768
 769         if (target_submit_prep(se_cmd, cmd->tvc_cdb, sg_ptr,
 770                                cmd->tvc_sgl_count, NULL, 0, sg_prot_ptr,
 771                                cmd->tvc_prot_sgl_count, GFP_KERNEL))
 772                 return;
 773
 774         target_queue_submission(se_cmd);
 775 }
 776
 777 static void
 778 vhost_scsi_send_bad_target(struct vhost_scsi *vs,
 779                            struct vhost_virtqueue *vq,
 780                            int head, unsigned out)
 781 {
 782         struct virtio_scsi_cmd_resp __user *resp;
 783         struct virtio_scsi_cmd_resp rsp;
 784         int ret;
 785
 786         memset(&rsp, 0, sizeof(rsp));
 787         rsp.response = VIRTIO_SCSI_S_BAD_TARGET;
 788         resp = vq->iov[out].iov_base;
 789         ret = __copy_to_user(resp, &rsp, sizeof(rsp));
 790         if (!ret)
 791                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 792         else
 793                 pr_err("Faulted on virtio_scsi_cmd_resp\n");
 794 }
 795
 796 static int
 797 vhost_scsi_get_desc(struct vhost_scsi *vs, struct vhost_virtqueue *vq,
 798                     struct vhost_scsi_ctx *vc)
 799 {
 800         int ret = -ENXIO;
 801
 802         vc->head = vhost_get_vq_desc(vq, vq->iov,
 803                                      ARRAY_SIZE(vq->iov), &vc->out, &vc->in,
 804                                      NULL, NULL);
 805
 806         pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n",
 807                  vc->head, vc->out, vc->in);
 808
 809         /* On error, stop handling until the next kick. */
 810         if (unlikely(vc->head < 0))
 811                 goto done;
 812
 813         /* Nothing new?  Wait for eventfd to tell us they refilled. */
 814         if (vc->head == vq->num) {
 815                 if (unlikely(vhost_enable_notify(&vs->dev, vq))) {
 816                         vhost_disable_notify(&vs->dev, vq);
 817                         ret = -EAGAIN;
 818                 }
 819                 goto done;
 820         }
 821
 822         /*
 823          * Get the size of request and response buffers.
 824          * FIXME: Not correct for BIDI operation
 825          */
 826         vc->out_size = iov_length(vq->iov, vc->out);
 827         vc->in_size = iov_length(&vq->iov[vc->out], vc->in);
 828
 829         /*
 830          * Copy over the virtio-scsi request header, which for a
 831          * ANY_LAYOUT enabled guest may span multiple iovecs, or a
 832          * single iovec may contain both the header + outgoing
 833          * WRITE payloads.
 834          *
 835          * copy_from_iter() will advance out_iter, so that it will
 836          * point at the start of the outgoing WRITE payload, if
 837          * DMA_TO_DEVICE is set.
 838          */
 839         iov_iter_init(&vc->out_iter, ITER_SOURCE, vq->iov, vc->out, vc->out_size);
 840         ret = 0;
 841
 842 done:
 843         return ret;
 844 }
 845
 846 static int
 847 vhost_scsi_chk_size(struct vhost_virtqueue *vq, struct vhost_scsi_ctx *vc)
 848 {
 849         if (unlikely(vc->in_size < vc->rsp_size)) {
 850                 vq_err(vq,
 851                        "Response buf too small, need min %zu bytes got %zu",
 852                        vc->rsp_size, vc->in_size);
 853                 return -EINVAL;
 854         } else if (unlikely(vc->out_size < vc->req_size)) {
 855                 vq_err(vq,
 856                        "Request buf too small, need min %zu bytes got %zu",
 857                        vc->req_size, vc->out_size);
 858                 return -EIO;
 859         }
 860
 861         return 0;
 862 }
 863
 864 static int
 865 vhost_scsi_get_req(struct vhost_virtqueue *vq, struct vhost_scsi_ctx *vc,
 866                    struct vhost_scsi_tpg **tpgp)
 867 {
 868         int ret = -EIO;
 869
 870         if (unlikely(!copy_from_iter_full(vc->req, vc->req_size,
 871                                           &vc->out_iter))) {
 872                 vq_err(vq, "Faulted on copy_from_iter_full\n");
 873         } else if (unlikely(*vc->lunp != 1)) {
 874                 /* virtio-scsi spec requires byte 0 of the lun to be 1 */
 875                 vq_err(vq, "Illegal virtio-scsi lun: %u\n", *vc->lunp);
 876         } else {
 877                 struct vhost_scsi_tpg **vs_tpg, *tpg;
 878
 879                 vs_tpg = vhost_vq_get_backend(vq);      /* validated at handler entry */
 880
 881                 tpg = READ_ONCE(vs_tpg[*vc->target]);
 882                 if (unlikely(!tpg)) {
 883                         vq_err(vq, "Target 0x%x does not exist\n", *vc->target);
 884                 } else {
 885                         if (tpgp)
 886                                 *tpgp = tpg;
 887                         ret = 0;
 888                 }
 889         }
 890
 891         return ret;
 892 }
 893
 894 static u16 vhost_buf_to_lun(u8 *lun_buf)
 895 {
 896         return ((lun_buf[2] << 8) | lun_buf[3]) & 0x3FFF;
 897 }
 898
 899 static void
 900 vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
 901 {
 902         struct vhost_scsi_tpg **vs_tpg, *tpg;
 903         struct virtio_scsi_cmd_req v_req;
 904         struct virtio_scsi_cmd_req_pi v_req_pi;
 905         struct vhost_scsi_ctx vc;
 906         struct vhost_scsi_cmd *cmd;
 907         struct iov_iter in_iter, prot_iter, data_iter;
 908         u64 tag;
 909         u32 exp_data_len, data_direction;
 910         int ret, prot_bytes, i, c = 0;
 911         u16 lun;
 912         u8 task_attr;
 913         bool t10_pi = vhost_has_feature(vq, VIRTIO_SCSI_F_T10_PI);
 914         void *cdb;
 915
 916         mutex_lock(&vq->mutex);
 917         /*
 918          * We can handle the vq only after the endpoint is setup by calling the
 919          * VHOST_SCSI_SET_ENDPOINT ioctl.
 920          */
 921         vs_tpg = vhost_vq_get_backend(vq);
 922         if (!vs_tpg)
 923                 goto out;
 924
 925         memset(&vc, 0, sizeof(vc));
 926         vc.rsp_size = sizeof(struct virtio_scsi_cmd_resp);
 927
 928         vhost_disable_notify(&vs->dev, vq);
 929
 930         do {
 931                 ret = vhost_scsi_get_desc(vs, vq, &vc);
 932                 if (ret)
 933                         goto err;
 934
 935                 /*
 936                  * Setup pointers and values based upon different virtio-scsi
 937                  * request header if T10_PI is enabled in KVM guest.
 938                  */
 939                 if (t10_pi) {
 940                         vc.req = &v_req_pi;
 941                         vc.req_size = sizeof(v_req_pi);
 942                         vc.lunp = &v_req_pi.lun[0];
 943                         vc.target = &v_req_pi.lun[1];
 944                 } else {
 945                         vc.req = &v_req;
 946                         vc.req_size = sizeof(v_req);
 947                         vc.lunp = &v_req.lun[0];
 948                         vc.target = &v_req.lun[1];
 949                 }
 950
 951                 /*
 952                  * Validate the size of request and response buffers.
 953                  * Check for a sane response buffer so we can report
 954                  * early errors back to the guest.
 955                  */
 956                 ret = vhost_scsi_chk_size(vq, &vc);
 957                 if (ret)
 958                         goto err;
 959
 960                 ret = vhost_scsi_get_req(vq, &vc, &tpg);
 961                 if (ret)
 962                         goto err;
 963
 964                 ret = -EIO;     /* bad target on any error from here on */
 965
 966                 /*
 967                  * Determine data_direction by calculating the total outgoing
 968                  * iovec sizes + incoming iovec sizes vs. virtio-scsi request +
 969                  * response headers respectively.
 970                  *
 971                  * For DMA_TO_DEVICE this is out_iter, which is already pointing
 972                  * to the right place.
 973                  *
 974                  * For DMA_FROM_DEVICE, the iovec will be just past the end
 975                  * of the virtio-scsi response header in either the same
 976                  * or immediately following iovec.
 977                  *
 978                  * Any associated T10_PI bytes for the outgoing / incoming
 979                  * payloads are included in calculation of exp_data_len here.
 980                  */
 981                 prot_bytes = 0;
 982
 983                 if (vc.out_size > vc.req_size) {
 984                         data_direction = DMA_TO_DEVICE;
 985                         exp_data_len = vc.out_size - vc.req_size;
 986                         data_iter = vc.out_iter;
 987                 } else if (vc.in_size > vc.rsp_size) {
 988                         data_direction = DMA_FROM_DEVICE;
 989                         exp_data_len = vc.in_size - vc.rsp_size;
 990
 991                         iov_iter_init(&in_iter, ITER_DEST, &vq->iov[vc.out], vc.in,
 992                                       vc.rsp_size + exp_data_len);
 993                         iov_iter_advance(&in_iter, vc.rsp_size);
 994                         data_iter = in_iter;
 995                 } else {
 996                         data_direction = DMA_NONE;
 997                         exp_data_len = 0;
 998                 }
 999                 /*
1000                  * If T10_PI header + payload is present, setup prot_iter values
1001                  * and recalculate data_iter for vhost_scsi_mapal() mapping to
1002                  * host scatterlists via get_user_pages_fast().
1003                  */
1004                 if (t10_pi) {
1005                         if (v_req_pi.pi_bytesout) {
1006                                 if (data_direction != DMA_TO_DEVICE) {
1007                                         vq_err(vq, "Received non zero pi_bytesout,"
1008                                                 " but wrong data_direction\n");
1009                                         goto err;
1010                                 }
1011                                 prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesout);
1012                         } else if (v_req_pi.pi_bytesin) {
1013                                 if (data_direction != DMA_FROM_DEVICE) {
1014                                         vq_err(vq, "Received non zero pi_bytesin,"
1015                                                 " but wrong data_direction\n");
1016                                         goto err;
1017                                 }
1018                                 prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesin);
1019                         }
1020                         /*
1021                          * Set prot_iter to data_iter and truncate it to
1022                          * prot_bytes, and advance data_iter past any
1023                          * preceeding prot_bytes that may be present.
1024                          *
1025                          * Also fix up the exp_data_len to reflect only the
1026                          * actual data payload length.
1027                          */
1028                         if (prot_bytes) {
1029                                 exp_data_len -= prot_bytes;
1030                                 prot_iter = data_iter;
1031                                 iov_iter_truncate(&prot_iter, prot_bytes);
1032                                 iov_iter_advance(&data_iter, prot_bytes);
1033                         }
1034                         tag = vhost64_to_cpu(vq, v_req_pi.tag);
1035                         task_attr = v_req_pi.task_attr;
1036                         cdb = &v_req_pi.cdb[0];
1037                         lun = vhost_buf_to_lun(v_req_pi.lun);
1038                 } else {
1039                         tag = vhost64_to_cpu(vq, v_req.tag);
1040                         task_attr = v_req.task_attr;
1041                         cdb = &v_req.cdb[0];
1042                         lun = vhost_buf_to_lun(v_req.lun);
1043                 }
1044                 /*
1045                  * Check that the received CDB size does not exceeded our
1046                  * hardcoded max for vhost-scsi, then get a pre-allocated
1047                  * cmd descriptor for the new virtio-scsi tag.
1048                  *
1049                  * TODO what if cdb was too small for varlen cdb header?
1050                  */
1051                 if (unlikely(scsi_command_size(cdb) > VHOST_SCSI_MAX_CDB_SIZE)) {
1052                         vq_err(vq, "Received SCSI CDB with command_size: %d that"
1053                                 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1054                                 scsi_command_size(cdb), VHOST_SCSI_MAX_CDB_SIZE);
1055                                 goto err;
1056                 }
1057                 cmd = vhost_scsi_get_cmd(vq, tpg, cdb, tag, lun, task_attr,
1058                                          exp_data_len + prot_bytes,
1059                                          data_direction);
1060                 if (IS_ERR(cmd)) {
1061                         vq_err(vq, "vhost_scsi_get_cmd failed %ld\n",
1062                                PTR_ERR(cmd));
1063                         goto err;
1064                 }
1065                 cmd->tvc_vhost = vs;
1066                 cmd->tvc_vq = vq;
1067                 for (i = 0; i < vc.in ; i++)
1068                         cmd->tvc_resp_iov[i] = vq->iov[vc.out + i];
1069                 cmd->tvc_in_iovs = vc.in;
1070
1071                 pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n",
1072                          cmd->tvc_cdb[0], cmd->tvc_lun);
1073                 pr_debug("cmd: %p exp_data_len: %d, prot_bytes: %d data_direction:"
1074                          " %d\n", cmd, exp_data_len, prot_bytes, data_direction);
1075
1076                 if (data_direction != DMA_NONE) {
1077                         if (unlikely(vhost_scsi_mapal(cmd, prot_bytes,
1078                                                       &prot_iter, exp_data_len,
1079                                                       &data_iter))) {
1080                                 vq_err(vq, "Failed to map iov to sgl\n");
1081                                 vhost_scsi_release_cmd_res(&cmd->tvc_se_cmd);
1082                                 goto err;
1083                         }
1084                 }
1085                 /*
1086                  * Save the descriptor from vhost_get_vq_desc() to be used to
1087                  * complete the virtio-scsi request in TCM callback context via
1088                  * vhost_scsi_queue_data_in() and vhost_scsi_queue_status()
1089                  */
1090                 cmd->tvc_vq_desc = vc.head;
1091                 vhost_scsi_target_queue_cmd(cmd);
1092                 ret = 0;
1093 err:
1094                 /*
1095                  * ENXIO:  No more requests, or read error, wait for next kick
1096                  * EINVAL: Invalid response buffer, drop the request
1097                  * EIO:    Respond with bad target
1098                  * EAGAIN: Pending request
1099                  */
1100                 if (ret == -ENXIO)
1101                         break;
1102                 else if (ret == -EIO)
1103                         vhost_scsi_send_bad_target(vs, vq, vc.head, vc.out);
1104         } while (likely(!vhost_exceeds_weight(vq, ++c, 0)));
1105 out:
1106         mutex_unlock(&vq->mutex);
1107 }
1108
1109 static void
1110 vhost_scsi_send_tmf_resp(struct vhost_scsi *vs, struct vhost_virtqueue *vq,
1111                          int in_iovs, int vq_desc, struct iovec *resp_iov,
1112                          int tmf_resp_code)
1113 {
1114         struct virtio_scsi_ctrl_tmf_resp rsp;
1115         struct iov_iter iov_iter;
1116         int ret;
1117
1118         pr_debug("%s\n", __func__);
1119         memset(&rsp, 0, sizeof(rsp));
1120         rsp.response = tmf_resp_code;
1121
1122         iov_iter_init(&iov_iter, ITER_DEST, resp_iov, in_iovs, sizeof(rsp));
1123
1124         ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter);
1125         if (likely(ret == sizeof(rsp)))
1126                 vhost_add_used_and_signal(&vs->dev, vq, vq_desc, 0);
1127         else
1128                 pr_err("Faulted on virtio_scsi_ctrl_tmf_resp\n");
1129 }
1130
1131 static void vhost_scsi_tmf_resp_work(struct vhost_work *work)
1132 {
1133         struct vhost_scsi_tmf *tmf = container_of(work, struct vhost_scsi_tmf,
1134                                                   vwork);
1135         int resp_code;
1136
1137         if (tmf->scsi_resp == TMR_FUNCTION_COMPLETE)
1138                 resp_code = VIRTIO_SCSI_S_FUNCTION_SUCCEEDED;
1139         else
1140                 resp_code = VIRTIO_SCSI_S_FUNCTION_REJECTED;
1141
1142         vhost_scsi_send_tmf_resp(tmf->vhost, &tmf->svq->vq, tmf->in_iovs,
1143                                  tmf->vq_desc, &tmf->resp_iov, resp_code);
1144         vhost_scsi_release_tmf_res(tmf);
1145 }
1146
1147 static void
1148 vhost_scsi_handle_tmf(struct vhost_scsi *vs, struct vhost_scsi_tpg *tpg,
1149                       struct vhost_virtqueue *vq,
1150                       struct virtio_scsi_ctrl_tmf_req *vtmf,
1151                       struct vhost_scsi_ctx *vc)
1152 {
1153         struct vhost_scsi_virtqueue *svq = container_of(vq,
1154                                         struct vhost_scsi_virtqueue, vq);
1155         struct vhost_scsi_tmf *tmf;
1156
1157         if (vhost32_to_cpu(vq, vtmf->subtype) !=
1158             VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET)
1159                 goto send_reject;
1160
1161         if (!tpg->tpg_nexus || !tpg->tpg_nexus->tvn_se_sess) {
1162                 pr_err("Unable to locate active struct vhost_scsi_nexus for LUN RESET.\n");
1163                 goto send_reject;
1164         }
1165
1166         tmf = kzalloc(sizeof(*tmf), GFP_KERNEL);
1167         if (!tmf)
1168                 goto send_reject;
1169
1170         vhost_work_init(&tmf->vwork, vhost_scsi_tmf_resp_work);
1171         tmf->vhost = vs;
1172         tmf->svq = svq;
1173         tmf->resp_iov = vq->iov[vc->out];
1174         tmf->vq_desc = vc->head;
1175         tmf->in_iovs = vc->in;
1176         tmf->inflight = vhost_scsi_get_inflight(vq);
1177
1178         if (target_submit_tmr(&tmf->se_cmd, tpg->tpg_nexus->tvn_se_sess, NULL,
1179                               vhost_buf_to_lun(vtmf->lun), NULL,
1180                               TMR_LUN_RESET, GFP_KERNEL, 0,
1181                               TARGET_SCF_ACK_KREF) < 0) {
1182                 vhost_scsi_release_tmf_res(tmf);
1183                 goto send_reject;
1184         }
1185
1186         return;
1187
1188 send_reject:
1189         vhost_scsi_send_tmf_resp(vs, vq, vc->in, vc->head, &vq->iov[vc->out],
1190                                  VIRTIO_SCSI_S_FUNCTION_REJECTED);
1191 }
1192
1193 static void
1194 vhost_scsi_send_an_resp(struct vhost_scsi *vs,
1195                         struct vhost_virtqueue *vq,
1196                         struct vhost_scsi_ctx *vc)
1197 {
1198         struct virtio_scsi_ctrl_an_resp rsp;
1199         struct iov_iter iov_iter;
1200         int ret;
1201
1202         pr_debug("%s\n", __func__);
1203         memset(&rsp, 0, sizeof(rsp));   /* event_actual = 0 */
1204         rsp.response = VIRTIO_SCSI_S_OK;
1205
1206         iov_iter_init(&iov_iter, ITER_DEST, &vq->iov[vc->out], vc->in, sizeof(rsp));
1207
1208         ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter);
1209         if (likely(ret == sizeof(rsp)))
1210                 vhost_add_used_and_signal(&vs->dev, vq, vc->head, 0);
1211         else
1212                 pr_err("Faulted on virtio_scsi_ctrl_an_resp\n");
1213 }
1214
1215 static void
1216 vhost_scsi_ctl_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
1217 {
1218         struct vhost_scsi_tpg *tpg;
1219         union {
1220                 __virtio32 type;
1221                 struct virtio_scsi_ctrl_an_req an;
1222                 struct virtio_scsi_ctrl_tmf_req tmf;
1223         } v_req;
1224         struct vhost_scsi_ctx vc;
1225         size_t typ_size;
1226         int ret, c = 0;
1227
1228         mutex_lock(&vq->mutex);
1229         /*
1230          * We can handle the vq only after the endpoint is setup by calling the
1231          * VHOST_SCSI_SET_ENDPOINT ioctl.
1232          */
1233         if (!vhost_vq_get_backend(vq))
1234                 goto out;
1235
1236         memset(&vc, 0, sizeof(vc));
1237
1238         vhost_disable_notify(&vs->dev, vq);
1239
1240         do {
1241                 ret = vhost_scsi_get_desc(vs, vq, &vc);
1242                 if (ret)
1243                         goto err;
1244
1245                 /*
1246                  * Get the request type first in order to setup
1247                  * other parameters dependent on the type.
1248                  */
1249                 vc.req = &v_req.type;
1250                 typ_size = sizeof(v_req.type);
1251
1252                 if (unlikely(!copy_from_iter_full(vc.req, typ_size,
1253                                                   &vc.out_iter))) {
1254                         vq_err(vq, "Faulted on copy_from_iter tmf type\n");
1255                         /*
1256                          * The size of the response buffer depends on the
1257                          * request type and must be validated against it.
1258                          * Since the request type is not known, don't send
1259                          * a response.
1260                          */
1261                         continue;
1262                 }
1263
1264                 switch (vhost32_to_cpu(vq, v_req.type)) {
1265                 case VIRTIO_SCSI_T_TMF:
1266                         vc.req = &v_req.tmf;
1267                         vc.req_size = sizeof(struct virtio_scsi_ctrl_tmf_req);
1268                         vc.rsp_size = sizeof(struct virtio_scsi_ctrl_tmf_resp);
1269                         vc.lunp = &v_req.tmf.lun[0];
1270                         vc.target = &v_req.tmf.lun[1];
1271                         break;
1272                 case VIRTIO_SCSI_T_AN_QUERY:
1273                 case VIRTIO_SCSI_T_AN_SUBSCRIBE:
1274                         vc.req = &v_req.an;
1275                         vc.req_size = sizeof(struct virtio_scsi_ctrl_an_req);
1276                         vc.rsp_size = sizeof(struct virtio_scsi_ctrl_an_resp);
1277                         vc.lunp = &v_req.an.lun[0];
1278                         vc.target = NULL;
1279                         break;
1280                 default:
1281                         vq_err(vq, "Unknown control request %d", v_req.type);
1282                         continue;
1283                 }
1284
1285                 /*
1286                  * Validate the size of request and response buffers.
1287                  * Check for a sane response buffer so we can report
1288                  * early errors back to the guest.
1289                  */
1290                 ret = vhost_scsi_chk_size(vq, &vc);
1291                 if (ret)
1292                         goto err;
1293
1294                 /*
1295                  * Get the rest of the request now that its size is known.
1296                  */
1297                 vc.req += typ_size;
1298                 vc.req_size -= typ_size;
1299
1300                 ret = vhost_scsi_get_req(vq, &vc, &tpg);
1301                 if (ret)
1302                         goto err;
1303
1304                 if (v_req.type == VIRTIO_SCSI_T_TMF)
1305                         vhost_scsi_handle_tmf(vs, tpg, vq, &v_req.tmf, &vc);
1306                 else
1307                         vhost_scsi_send_an_resp(vs, vq, &vc);
1308 err:
1309                 /*
1310                  * ENXIO:  No more requests, or read error, wait for next kick
1311                  * EINVAL: Invalid response buffer, drop the request
1312                  * EIO:    Respond with bad target
1313                  * EAGAIN: Pending request
1314                  */
1315                 if (ret == -ENXIO)
1316                         break;
1317                 else if (ret == -EIO)
1318                         vhost_scsi_send_bad_target(vs, vq, vc.head, vc.out);
1319         } while (likely(!vhost_exceeds_weight(vq, ++c, 0)));
1320 out:
1321         mutex_unlock(&vq->mutex);
1322 }
1323
1324 static void vhost_scsi_ctl_handle_kick(struct vhost_work *work)
1325 {
1326         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1327                                                 poll.work);
1328         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1329
1330         pr_debug("%s: The handling func for control queue.\n", __func__);
1331         vhost_scsi_ctl_handle_vq(vs, vq);
1332 }
1333
1334 static void
1335 vhost_scsi_send_evt(struct vhost_scsi *vs,
1336                    struct vhost_scsi_tpg *tpg,
1337                    struct se_lun *lun,
1338                    u32 event,
1339                    u32 reason)
1340 {
1341         struct vhost_scsi_evt *evt;
1342
1343         evt = vhost_scsi_allocate_evt(vs, event, reason);
1344         if (!evt)
1345                 return;
1346
1347         if (tpg && lun) {
1348                 /* TODO: share lun setup code with virtio-scsi.ko */
1349                 /*
1350                  * Note: evt->event is zeroed when we allocate it and
1351                  * lun[4-7] need to be zero according to virtio-scsi spec.
1352                  */
1353                 evt->event.lun[0] = 0x01;
1354                 evt->event.lun[1] = tpg->tport_tpgt;
1355                 if (lun->unpacked_lun >= 256)
1356                         evt->event.lun[2] = lun->unpacked_lun >> 8 | 0x40 ;
1357                 evt->event.lun[3] = lun->unpacked_lun & 0xFF;
1358         }
1359
1360         llist_add(&evt->list, &vs->vs_event_list);
1361         vhost_work_queue(&vs->dev, &vs->vs_event_work);
1362 }
1363
1364 static void vhost_scsi_evt_handle_kick(struct vhost_work *work)
1365 {
1366         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1367                                                 poll.work);
1368         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1369
1370         mutex_lock(&vq->mutex);
1371         if (!vhost_vq_get_backend(vq))
1372                 goto out;
1373
1374         if (vs->vs_events_missed)
1375                 vhost_scsi_send_evt(vs, NULL, NULL, VIRTIO_SCSI_T_NO_EVENT, 0);
1376 out:
1377         mutex_unlock(&vq->mutex);
1378 }
1379
1380 static void vhost_scsi_handle_kick(struct vhost_work *work)
1381 {
1382         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1383                                                 poll.work);
1384         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1385
1386         vhost_scsi_handle_vq(vs, vq);
1387 }
1388
1389 /* Callers must hold dev mutex */
1390 static void vhost_scsi_flush(struct vhost_scsi *vs)
1391 {
1392         int i;
1393
1394         /* Init new inflight and remember the old inflight */
1395         vhost_scsi_init_inflight(vs, vs->old_inflight);
1396
1397         /*
1398          * The inflight->kref was initialized to 1. We decrement it here to
1399          * indicate the start of the flush operation so that it will reach 0
1400          * when all the reqs are finished.
1401          */
1402         for (i = 0; i < vs->dev.nvqs; i++)
1403                 kref_put(&vs->old_inflight[i]->kref, vhost_scsi_done_inflight);
1404
1405         /* Flush both the vhost poll and vhost work */
1406         vhost_dev_flush(&vs->dev);
1407
1408         /* Wait for all reqs issued before the flush to be finished */
1409         for (i = 0; i < vs->dev.nvqs; i++)
1410                 wait_for_completion(&vs->old_inflight[i]->comp);
1411 }
1412
1413 static void vhost_scsi_destroy_vq_cmds(struct vhost_virtqueue *vq)
1414 {
1415         struct vhost_scsi_virtqueue *svq = container_of(vq,
1416                                         struct vhost_scsi_virtqueue, vq);
1417         struct vhost_scsi_cmd *tv_cmd;
1418         unsigned int i;
1419
1420         if (!svq->scsi_cmds)
1421                 return;
1422
1423         for (i = 0; i < svq->max_cmds; i++) {
1424                 tv_cmd = &svq->scsi_cmds[i];
1425
1426                 kfree(tv_cmd->tvc_sgl);
1427                 kfree(tv_cmd->tvc_prot_sgl);
1428                 kfree(tv_cmd->tvc_upages);
1429                 kfree(tv_cmd->tvc_resp_iov);
1430         }
1431
1432         sbitmap_free(&svq->scsi_tags);
1433         kfree(svq->scsi_cmds);
1434         svq->scsi_cmds = NULL;
1435 }
1436
1437 static int vhost_scsi_setup_vq_cmds(struct vhost_virtqueue *vq, int max_cmds)
1438 {
1439         struct vhost_scsi_virtqueue *svq = container_of(vq,
1440                                         struct vhost_scsi_virtqueue, vq);
1441         struct vhost_scsi_cmd *tv_cmd;
1442         unsigned int i;
1443
1444         if (svq->scsi_cmds)
1445                 return 0;
1446
1447         if (sbitmap_init_node(&svq->scsi_tags, max_cmds, -1, GFP_KERNEL,
1448                               NUMA_NO_NODE, false, true))
1449                 return -ENOMEM;
1450         svq->max_cmds = max_cmds;
1451
1452         svq->scsi_cmds = kcalloc(max_cmds, sizeof(*tv_cmd), GFP_KERNEL);
1453         if (!svq->scsi_cmds) {
1454                 sbitmap_free(&svq->scsi_tags);
1455                 return -ENOMEM;
1456         }
1457
1458         for (i = 0; i < max_cmds; i++) {
1459                 tv_cmd = &svq->scsi_cmds[i];
1460
1461                 tv_cmd->tvc_sgl = kcalloc(VHOST_SCSI_PREALLOC_SGLS,
1462                                           sizeof(struct scatterlist),
1463                                           GFP_KERNEL);
1464                 if (!tv_cmd->tvc_sgl) {
1465                         pr_err("Unable to allocate tv_cmd->tvc_sgl\n");
1466                         goto out;
1467                 }
1468
1469                 tv_cmd->tvc_upages = kcalloc(VHOST_SCSI_PREALLOC_UPAGES,
1470                                              sizeof(struct page *),
1471                                              GFP_KERNEL);
1472                 if (!tv_cmd->tvc_upages) {
1473                         pr_err("Unable to allocate tv_cmd->tvc_upages\n");
1474                         goto out;
1475                 }
1476
1477                 tv_cmd->tvc_resp_iov = kcalloc(UIO_MAXIOV,
1478                                                sizeof(struct iovec),
1479                                                GFP_KERNEL);
1480                 if (!tv_cmd->tvc_resp_iov) {
1481                         pr_err("Unable to allocate tv_cmd->tvc_resp_iov\n");
1482                         goto out;
1483                 }
1484
1485                 tv_cmd->tvc_prot_sgl = kcalloc(VHOST_SCSI_PREALLOC_PROT_SGLS,
1486                                                sizeof(struct scatterlist),
1487                                                GFP_KERNEL);
1488                 if (!tv_cmd->tvc_prot_sgl) {
1489                         pr_err("Unable to allocate tv_cmd->tvc_prot_sgl\n");
1490                         goto out;
1491                 }
1492         }
1493         return 0;
1494 out:
1495         vhost_scsi_destroy_vq_cmds(vq);
1496         return -ENOMEM;
1497 }
1498
1499 /*
1500  * Called from vhost_scsi_ioctl() context to walk the list of available
1501  * vhost_scsi_tpg with an active struct vhost_scsi_nexus
1502  *
1503  *  The lock nesting rule is:
1504  *    vhost_scsi_mutex -> vs->dev.mutex -> tpg->tv_tpg_mutex -> vq->mutex
1505  */
1506 static int
1507 vhost_scsi_set_endpoint(struct vhost_scsi *vs,
1508                         struct vhost_scsi_target *t)
1509 {
1510         struct se_portal_group *se_tpg;
1511         struct vhost_scsi_tport *tv_tport;
1512         struct vhost_scsi_tpg *tpg;
1513         struct vhost_scsi_tpg **vs_tpg;
1514         struct vhost_virtqueue *vq;
1515         int index, ret, i, len;
1516         bool match = false;
1517
1518         mutex_lock(&vhost_scsi_mutex);
1519         mutex_lock(&vs->dev.mutex);
1520
1521         /* Verify that ring has been setup correctly. */
1522         for (index = 0; index < vs->dev.nvqs; ++index) {
1523                 /* Verify that ring has been setup correctly. */
1524                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1525                         ret = -EFAULT;
1526                         goto out;
1527                 }
1528         }
1529
1530         len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET;
1531         vs_tpg = kzalloc(len, GFP_KERNEL);
1532         if (!vs_tpg) {
1533                 ret = -ENOMEM;
1534                 goto out;
1535         }
1536         if (vs->vs_tpg)
1537                 memcpy(vs_tpg, vs->vs_tpg, len);
1538
1539         list_for_each_entry(tpg, &vhost_scsi_list, tv_tpg_list) {
1540                 mutex_lock(&tpg->tv_tpg_mutex);
1541                 if (!tpg->tpg_nexus) {
1542                         mutex_unlock(&tpg->tv_tpg_mutex);
1543                         continue;
1544                 }
1545                 if (tpg->tv_tpg_vhost_count != 0) {
1546                         mutex_unlock(&tpg->tv_tpg_mutex);
1547                         continue;
1548                 }
1549                 tv_tport = tpg->tport;
1550
1551                 if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1552                         if (vs->vs_tpg && vs->vs_tpg[tpg->tport_tpgt]) {
1553                                 mutex_unlock(&tpg->tv_tpg_mutex);
1554                                 ret = -EEXIST;
1555                                 goto undepend;
1556                         }
1557                         /*
1558                          * In order to ensure individual vhost-scsi configfs
1559                          * groups cannot be removed while in use by vhost ioctl,
1560                          * go ahead and take an explicit se_tpg->tpg_group.cg_item
1561                          * dependency now.
1562                          */
1563                         se_tpg = &tpg->se_tpg;
1564                         ret = target_depend_item(&se_tpg->tpg_group.cg_item);
1565                         if (ret) {
1566                                 pr_warn("target_depend_item() failed: %d\n", ret);
1567                                 mutex_unlock(&tpg->tv_tpg_mutex);
1568                                 goto undepend;
1569                         }
1570                         tpg->tv_tpg_vhost_count++;
1571                         tpg->vhost_scsi = vs;
1572                         vs_tpg[tpg->tport_tpgt] = tpg;
1573                         match = true;
1574                 }
1575                 mutex_unlock(&tpg->tv_tpg_mutex);
1576         }
1577
1578         if (match) {
1579                 memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
1580                        sizeof(vs->vs_vhost_wwpn));
1581
1582                 for (i = VHOST_SCSI_VQ_IO; i < vs->dev.nvqs; i++) {
1583                         vq = &vs->vqs[i].vq;
1584                         if (!vhost_vq_is_setup(vq))
1585                                 continue;
1586
1587                         ret = vhost_scsi_setup_vq_cmds(vq, vq->num);
1588                         if (ret)
1589                                 goto destroy_vq_cmds;
1590                 }
1591
1592                 for (i = 0; i < vs->dev.nvqs; i++) {
1593                         vq = &vs->vqs[i].vq;
1594                         mutex_lock(&vq->mutex);
1595                         vhost_vq_set_backend(vq, vs_tpg);
1596                         vhost_vq_init_access(vq);
1597                         mutex_unlock(&vq->mutex);
1598                 }
1599                 ret = 0;
1600         } else {
1601                 ret = -EEXIST;
1602         }
1603
1604         /*
1605          * Act as synchronize_rcu to make sure access to
1606          * old vs->vs_tpg is finished.
1607          */
1608         vhost_scsi_flush(vs);
1609         kfree(vs->vs_tpg);
1610         vs->vs_tpg = vs_tpg;
1611         goto out;
1612
1613 destroy_vq_cmds:
1614         for (i--; i >= VHOST_SCSI_VQ_IO; i--) {
1615                 if (!vhost_vq_get_backend(&vs->vqs[i].vq))
1616                         vhost_scsi_destroy_vq_cmds(&vs->vqs[i].vq);
1617         }
1618 undepend:
1619         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1620                 tpg = vs_tpg[i];
1621                 if (tpg) {
1622                         mutex_lock(&tpg->tv_tpg_mutex);
1623                         tpg->vhost_scsi = NULL;
1624                         tpg->tv_tpg_vhost_count--;
1625                         mutex_unlock(&tpg->tv_tpg_mutex);
1626                         target_undepend_item(&tpg->se_tpg.tpg_group.cg_item);
1627                 }
1628         }
1629         kfree(vs_tpg);
1630 out:
1631         mutex_unlock(&vs->dev.mutex);
1632         mutex_unlock(&vhost_scsi_mutex);
1633         return ret;
1634 }
1635
1636 static int
1637 vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
1638                           struct vhost_scsi_target *t)
1639 {
1640         struct se_portal_group *se_tpg;
1641         struct vhost_scsi_tport *tv_tport;
1642         struct vhost_scsi_tpg *tpg;
1643         struct vhost_virtqueue *vq;
1644         bool match = false;
1645         int index, ret, i;
1646         u8 target;
1647
1648         mutex_lock(&vhost_scsi_mutex);
1649         mutex_lock(&vs->dev.mutex);
1650         /* Verify that ring has been setup correctly. */
1651         for (index = 0; index < vs->dev.nvqs; ++index) {
1652                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1653                         ret = -EFAULT;
1654                         goto err_dev;
1655                 }
1656         }
1657
1658         if (!vs->vs_tpg) {
1659                 ret = 0;
1660                 goto err_dev;
1661         }
1662
1663         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1664                 target = i;
1665                 tpg = vs->vs_tpg[target];
1666                 if (!tpg)
1667                         continue;
1668
1669                 mutex_lock(&tpg->tv_tpg_mutex);
1670                 tv_tport = tpg->tport;
1671                 if (!tv_tport) {
1672                         ret = -ENODEV;
1673                         goto err_tpg;
1674                 }
1675
1676                 if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1677                         pr_warn("tv_tport->tport_name: %s, tpg->tport_tpgt: %hu"
1678                                 " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
1679                                 tv_tport->tport_name, tpg->tport_tpgt,
1680                                 t->vhost_wwpn, t->vhost_tpgt);
1681                         ret = -EINVAL;
1682                         goto err_tpg;
1683                 }
1684                 tpg->tv_tpg_vhost_count--;
1685                 tpg->vhost_scsi = NULL;
1686                 vs->vs_tpg[target] = NULL;
1687                 match = true;
1688                 mutex_unlock(&tpg->tv_tpg_mutex);
1689                 /*
1690                  * Release se_tpg->tpg_group.cg_item configfs dependency now
1691                  * to allow vhost-scsi WWPN se_tpg->tpg_group shutdown to occur.
1692                  */
1693                 se_tpg = &tpg->se_tpg;
1694                 target_undepend_item(&se_tpg->tpg_group.cg_item);
1695         }
1696         if (match) {
1697                 for (i = 0; i < vs->dev.nvqs; i++) {
1698                         vq = &vs->vqs[i].vq;
1699                         mutex_lock(&vq->mutex);
1700                         vhost_vq_set_backend(vq, NULL);
1701                         mutex_unlock(&vq->mutex);
1702                 }
1703                 /* Make sure cmds are not running before tearing them down. */
1704                 vhost_scsi_flush(vs);
1705
1706                 for (i = 0; i < vs->dev.nvqs; i++) {
1707                         vq = &vs->vqs[i].vq;
1708                         vhost_scsi_destroy_vq_cmds(vq);
1709                 }
1710         }
1711         /*
1712          * Act as synchronize_rcu to make sure access to
1713          * old vs->vs_tpg is finished.
1714          */
1715         vhost_scsi_flush(vs);
1716         kfree(vs->vs_tpg);
1717         vs->vs_tpg = NULL;
1718         WARN_ON(vs->vs_events_nr);
1719         mutex_unlock(&vs->dev.mutex);
1720         mutex_unlock(&vhost_scsi_mutex);
1721         return 0;
1722
1723 err_tpg:
1724         mutex_unlock(&tpg->tv_tpg_mutex);
1725 err_dev:
1726         mutex_unlock(&vs->dev.mutex);
1727         mutex_unlock(&vhost_scsi_mutex);
1728         return ret;
1729 }
1730
1731 static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features)
1732 {
1733         struct vhost_virtqueue *vq;
1734         int i;
1735
1736         if (features & ~VHOST_SCSI_FEATURES)
1737                 return -EOPNOTSUPP;
1738
1739         mutex_lock(&vs->dev.mutex);
1740         if ((features & (1 << VHOST_F_LOG_ALL)) &&
1741             !vhost_log_access_ok(&vs->dev)) {
1742                 mutex_unlock(&vs->dev.mutex);
1743                 return -EFAULT;
1744         }
1745
1746         for (i = 0; i < vs->dev.nvqs; i++) {
1747                 vq = &vs->vqs[i].vq;
1748                 mutex_lock(&vq->mutex);
1749                 vq->acked_features = features;
1750                 mutex_unlock(&vq->mutex);
1751         }
1752         mutex_unlock(&vs->dev.mutex);
1753         return 0;
1754 }
1755
1756 static int vhost_scsi_open(struct inode *inode, struct file *f)
1757 {
1758         struct vhost_scsi *vs;
1759         struct vhost_virtqueue **vqs;
1760         int r = -ENOMEM, i, nvqs = vhost_scsi_max_io_vqs;
1761
1762         vs = kvzalloc(sizeof(*vs), GFP_KERNEL);
1763         if (!vs)
1764                 goto err_vs;
1765
1766         if (nvqs > VHOST_SCSI_MAX_IO_VQ) {
1767                 pr_err("Invalid max_io_vqs of %d. Using %d.\n", nvqs,
1768                        VHOST_SCSI_MAX_IO_VQ);
1769                 nvqs = VHOST_SCSI_MAX_IO_VQ;
1770         } else if (nvqs == 0) {
1771                 pr_err("Invalid max_io_vqs of %d. Using 1.\n", nvqs);
1772                 nvqs = 1;
1773         }
1774         nvqs += VHOST_SCSI_VQ_IO;
1775
1776         vs->compl_bitmap = bitmap_alloc(nvqs, GFP_KERNEL);
1777         if (!vs->compl_bitmap)
1778                 goto err_compl_bitmap;
1779
1780         vs->old_inflight = kmalloc_array(nvqs, sizeof(*vs->old_inflight),
1781                                          GFP_KERNEL | __GFP_ZERO);
1782         if (!vs->old_inflight)
1783                 goto err_inflight;
1784
1785         vs->vqs = kmalloc_array(nvqs, sizeof(*vs->vqs),
1786                                 GFP_KERNEL | __GFP_ZERO);
1787         if (!vs->vqs)
1788                 goto err_vqs;
1789
1790         vqs = kmalloc_array(nvqs, sizeof(*vqs), GFP_KERNEL);
1791         if (!vqs)
1792                 goto err_local_vqs;
1793
1794         vhost_work_init(&vs->vs_completion_work, vhost_scsi_complete_cmd_work);
1795         vhost_work_init(&vs->vs_event_work, vhost_scsi_evt_work);
1796
1797         vs->vs_events_nr = 0;
1798         vs->vs_events_missed = false;
1799
1800         vqs[VHOST_SCSI_VQ_CTL] = &vs->vqs[VHOST_SCSI_VQ_CTL].vq;
1801         vqs[VHOST_SCSI_VQ_EVT] = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1802         vs->vqs[VHOST_SCSI_VQ_CTL].vq.handle_kick = vhost_scsi_ctl_handle_kick;
1803         vs->vqs[VHOST_SCSI_VQ_EVT].vq.handle_kick = vhost_scsi_evt_handle_kick;
1804         for (i = VHOST_SCSI_VQ_IO; i < nvqs; i++) {
1805                 vqs[i] = &vs->vqs[i].vq;
1806                 vs->vqs[i].vq.handle_kick = vhost_scsi_handle_kick;
1807         }
1808         vhost_dev_init(&vs->dev, vqs, nvqs, UIO_MAXIOV,
1809                        VHOST_SCSI_WEIGHT, 0, true, NULL);
1810
1811         vhost_scsi_init_inflight(vs, NULL);
1812
1813         f->private_data = vs;
1814         return 0;
1815
1816 err_local_vqs:
1817         kfree(vs->vqs);
1818 err_vqs:
1819         kfree(vs->old_inflight);
1820 err_inflight:
1821         bitmap_free(vs->compl_bitmap);
1822 err_compl_bitmap:
1823         kvfree(vs);
1824 err_vs:
1825         return r;
1826 }
1827
1828 static int vhost_scsi_release(struct inode *inode, struct file *f)
1829 {
1830         struct vhost_scsi *vs = f->private_data;
1831         struct vhost_scsi_target t;
1832
1833         mutex_lock(&vs->dev.mutex);
1834         memcpy(t.vhost_wwpn, vs->vs_vhost_wwpn, sizeof(t.vhost_wwpn));
1835         mutex_unlock(&vs->dev.mutex);
1836         vhost_scsi_clear_endpoint(vs, &t);
1837         vhost_dev_stop(&vs->dev);
1838         vhost_dev_cleanup(&vs->dev);
1839         kfree(vs->dev.vqs);
1840         kfree(vs->vqs);
1841         kfree(vs->old_inflight);
1842         bitmap_free(vs->compl_bitmap);
1843         kvfree(vs);
1844         return 0;
1845 }
1846
1847 static long
1848 vhost_scsi_ioctl(struct file *f,
1849                  unsigned int ioctl,
1850                  unsigned long arg)
1851 {
1852         struct vhost_scsi *vs = f->private_data;
1853         struct vhost_scsi_target backend;
1854         void __user *argp = (void __user *)arg;
1855         u64 __user *featurep = argp;
1856         u32 __user *eventsp = argp;
1857         u32 events_missed;
1858         u64 features;
1859         int r, abi_version = VHOST_SCSI_ABI_VERSION;
1860         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1861
1862         switch (ioctl) {
1863         case VHOST_SCSI_SET_ENDPOINT:
1864                 if (copy_from_user(&backend, argp, sizeof backend))
1865                         return -EFAULT;
1866                 if (backend.reserved != 0)
1867                         return -EOPNOTSUPP;
1868
1869                 return vhost_scsi_set_endpoint(vs, &backend);
1870         case VHOST_SCSI_CLEAR_ENDPOINT:
1871                 if (copy_from_user(&backend, argp, sizeof backend))
1872                         return -EFAULT;
1873                 if (backend.reserved != 0)
1874                         return -EOPNOTSUPP;
1875
1876                 return vhost_scsi_clear_endpoint(vs, &backend);
1877         case VHOST_SCSI_GET_ABI_VERSION:
1878                 if (copy_to_user(argp, &abi_version, sizeof abi_version))
1879                         return -EFAULT;
1880                 return 0;
1881         case VHOST_SCSI_SET_EVENTS_MISSED:
1882                 if (get_user(events_missed, eventsp))
1883                         return -EFAULT;
1884                 mutex_lock(&vq->mutex);
1885                 vs->vs_events_missed = events_missed;
1886                 mutex_unlock(&vq->mutex);
1887                 return 0;
1888         case VHOST_SCSI_GET_EVENTS_MISSED:
1889                 mutex_lock(&vq->mutex);
1890                 events_missed = vs->vs_events_missed;
1891                 mutex_unlock(&vq->mutex);
1892                 if (put_user(events_missed, eventsp))
1893                         return -EFAULT;
1894                 return 0;
1895         case VHOST_GET_FEATURES:
1896                 features = VHOST_SCSI_FEATURES;
1897                 if (copy_to_user(featurep, &features, sizeof features))
1898                         return -EFAULT;
1899                 return 0;
1900         case VHOST_SET_FEATURES:
1901                 if (copy_from_user(&features, featurep, sizeof features))
1902                         return -EFAULT;
1903                 return vhost_scsi_set_features(vs, features);
1904         default:
1905                 mutex_lock(&vs->dev.mutex);
1906                 r = vhost_dev_ioctl(&vs->dev, ioctl, argp);
1907                 /* TODO: flush backend after dev ioctl. */
1908                 if (r == -ENOIOCTLCMD)
1909                         r = vhost_vring_ioctl(&vs->dev, ioctl, argp);
1910                 mutex_unlock(&vs->dev.mutex);
1911                 return r;
1912         }
1913 }
1914
1915 static const struct file_operations vhost_scsi_fops = {
1916         .owner          = THIS_MODULE,
1917         .release        = vhost_scsi_release,
1918         .unlocked_ioctl = vhost_scsi_ioctl,
1919         .compat_ioctl   = compat_ptr_ioctl,
1920         .open           = vhost_scsi_open,
1921         .llseek         = noop_llseek,
1922 };
1923
1924 static struct miscdevice vhost_scsi_misc = {
1925         MISC_DYNAMIC_MINOR,
1926         "vhost-scsi",
1927         &vhost_scsi_fops,
1928 };
1929
1930 static int __init vhost_scsi_register(void)
1931 {
1932         return misc_register(&vhost_scsi_misc);
1933 }
1934
1935 static void vhost_scsi_deregister(void)
1936 {
1937         misc_deregister(&vhost_scsi_misc);
1938 }
1939
1940 static char *vhost_scsi_dump_proto_id(struct vhost_scsi_tport *tport)
1941 {
1942         switch (tport->tport_proto_id) {
1943         case SCSI_PROTOCOL_SAS:
1944                 return "SAS";
1945         case SCSI_PROTOCOL_FCP:
1946                 return "FCP";
1947         case SCSI_PROTOCOL_ISCSI:
1948                 return "iSCSI";
1949         default:
1950                 break;
1951         }
1952
1953         return "Unknown";
1954 }
1955
1956 static void
1957 vhost_scsi_do_plug(struct vhost_scsi_tpg *tpg,
1958                   struct se_lun *lun, bool plug)
1959 {
1960
1961         struct vhost_scsi *vs = tpg->vhost_scsi;
1962         struct vhost_virtqueue *vq;
1963         u32 reason;
1964
1965         if (!vs)
1966                 return;
1967
1968         mutex_lock(&vs->dev.mutex);
1969
1970         if (plug)
1971                 reason = VIRTIO_SCSI_EVT_RESET_RESCAN;
1972         else
1973                 reason = VIRTIO_SCSI_EVT_RESET_REMOVED;
1974
1975         vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1976         mutex_lock(&vq->mutex);
1977         if (vhost_has_feature(vq, VIRTIO_SCSI_F_HOTPLUG))
1978                 vhost_scsi_send_evt(vs, tpg, lun,
1979                                    VIRTIO_SCSI_T_TRANSPORT_RESET, reason);
1980         mutex_unlock(&vq->mutex);
1981         mutex_unlock(&vs->dev.mutex);
1982 }
1983
1984 static void vhost_scsi_hotplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
1985 {
1986         vhost_scsi_do_plug(tpg, lun, true);
1987 }
1988
1989 static void vhost_scsi_hotunplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
1990 {
1991         vhost_scsi_do_plug(tpg, lun, false);
1992 }
1993
1994 static int vhost_scsi_port_link(struct se_portal_group *se_tpg,
1995                                struct se_lun *lun)
1996 {
1997         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
1998                                 struct vhost_scsi_tpg, se_tpg);
1999
2000         mutex_lock(&vhost_scsi_mutex);
2001
2002         mutex_lock(&tpg->tv_tpg_mutex);
2003         tpg->tv_tpg_port_count++;
2004         mutex_unlock(&tpg->tv_tpg_mutex);
2005
2006         vhost_scsi_hotplug(tpg, lun);
2007
2008         mutex_unlock(&vhost_scsi_mutex);
2009
2010         return 0;
2011 }
2012
2013 static void vhost_scsi_port_unlink(struct se_portal_group *se_tpg,
2014                                   struct se_lun *lun)
2015 {
2016         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2017                                 struct vhost_scsi_tpg, se_tpg);
2018
2019         mutex_lock(&vhost_scsi_mutex);
2020
2021         mutex_lock(&tpg->tv_tpg_mutex);
2022         tpg->tv_tpg_port_count--;
2023         mutex_unlock(&tpg->tv_tpg_mutex);
2024
2025         vhost_scsi_hotunplug(tpg, lun);
2026
2027         mutex_unlock(&vhost_scsi_mutex);
2028 }
2029
2030 static ssize_t vhost_scsi_tpg_attrib_fabric_prot_type_store(
2031                 struct config_item *item, const char *page, size_t count)
2032 {
2033         struct se_portal_group *se_tpg = attrib_to_tpg(item);
2034         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2035                                 struct vhost_scsi_tpg, se_tpg);
2036         unsigned long val;
2037         int ret = kstrtoul(page, 0, &val);
2038
2039         if (ret) {
2040                 pr_err("kstrtoul() returned %d for fabric_prot_type\n", ret);
2041                 return ret;
2042         }
2043         if (val != 0 && val != 1 && val != 3) {
2044                 pr_err("Invalid vhost_scsi fabric_prot_type: %lu\n", val);
2045                 return -EINVAL;
2046         }
2047         tpg->tv_fabric_prot_type = val;
2048
2049         return count;
2050 }
2051
2052 static ssize_t vhost_scsi_tpg_attrib_fabric_prot_type_show(
2053                 struct config_item *item, char *page)
2054 {
2055         struct se_portal_group *se_tpg = attrib_to_tpg(item);
2056         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2057                                 struct vhost_scsi_tpg, se_tpg);
2058
2059         return sysfs_emit(page, "%d\n", tpg->tv_fabric_prot_type);
2060 }
2061
2062 CONFIGFS_ATTR(vhost_scsi_tpg_attrib_, fabric_prot_type);
2063
2064 static struct configfs_attribute *vhost_scsi_tpg_attrib_attrs[] = {
2065         &vhost_scsi_tpg_attrib_attr_fabric_prot_type,
2066         NULL,
2067 };
2068
2069 static int vhost_scsi_make_nexus(struct vhost_scsi_tpg *tpg,
2070                                 const char *name)
2071 {
2072         struct vhost_scsi_nexus *tv_nexus;
2073
2074         mutex_lock(&tpg->tv_tpg_mutex);
2075         if (tpg->tpg_nexus) {
2076                 mutex_unlock(&tpg->tv_tpg_mutex);
2077                 pr_debug("tpg->tpg_nexus already exists\n");
2078                 return -EEXIST;
2079         }
2080
2081         tv_nexus = kzalloc(sizeof(*tv_nexus), GFP_KERNEL);
2082         if (!tv_nexus) {
2083                 mutex_unlock(&tpg->tv_tpg_mutex);
2084                 pr_err("Unable to allocate struct vhost_scsi_nexus\n");
2085                 return -ENOMEM;
2086         }
2087         /*
2088          * Since we are running in 'demo mode' this call with generate a
2089          * struct se_node_acl for the vhost_scsi struct se_portal_group with
2090          * the SCSI Initiator port name of the passed configfs group 'name'.
2091          */
2092         tv_nexus->tvn_se_sess = target_setup_session(&tpg->se_tpg, 0, 0,
2093                                         TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS,
2094                                         (unsigned char *)name, tv_nexus, NULL);
2095         if (IS_ERR(tv_nexus->tvn_se_sess)) {
2096                 mutex_unlock(&tpg->tv_tpg_mutex);
2097                 kfree(tv_nexus);
2098                 return -ENOMEM;
2099         }
2100         tpg->tpg_nexus = tv_nexus;
2101
2102         mutex_unlock(&tpg->tv_tpg_mutex);
2103         return 0;
2104 }
2105
2106 static int vhost_scsi_drop_nexus(struct vhost_scsi_tpg *tpg)
2107 {
2108         struct se_session *se_sess;
2109         struct vhost_scsi_nexus *tv_nexus;
2110
2111         mutex_lock(&tpg->tv_tpg_mutex);
2112         tv_nexus = tpg->tpg_nexus;
2113         if (!tv_nexus) {
2114                 mutex_unlock(&tpg->tv_tpg_mutex);
2115                 return -ENODEV;
2116         }
2117
2118         se_sess = tv_nexus->tvn_se_sess;
2119         if (!se_sess) {
2120                 mutex_unlock(&tpg->tv_tpg_mutex);
2121                 return -ENODEV;
2122         }
2123
2124         if (tpg->tv_tpg_port_count != 0) {
2125                 mutex_unlock(&tpg->tv_tpg_mutex);
2126                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
2127                         " active TPG port count: %d\n",
2128                         tpg->tv_tpg_port_count);
2129                 return -EBUSY;
2130         }
2131
2132         if (tpg->tv_tpg_vhost_count != 0) {
2133                 mutex_unlock(&tpg->tv_tpg_mutex);
2134                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
2135                         " active TPG vhost count: %d\n",
2136                         tpg->tv_tpg_vhost_count);
2137                 return -EBUSY;
2138         }
2139
2140         pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated"
2141                 " %s Initiator Port: %s\n", vhost_scsi_dump_proto_id(tpg->tport),
2142                 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
2143
2144         /*
2145          * Release the SCSI I_T Nexus to the emulated vhost Target Port
2146          */
2147         target_remove_session(se_sess);
2148         tpg->tpg_nexus = NULL;
2149         mutex_unlock(&tpg->tv_tpg_mutex);
2150
2151         kfree(tv_nexus);
2152         return 0;
2153 }
2154
2155 static ssize_t vhost_scsi_tpg_nexus_show(struct config_item *item, char *page)
2156 {
2157         struct se_portal_group *se_tpg = to_tpg(item);
2158         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2159                                 struct vhost_scsi_tpg, se_tpg);
2160         struct vhost_scsi_nexus *tv_nexus;
2161         ssize_t ret;
2162
2163         mutex_lock(&tpg->tv_tpg_mutex);
2164         tv_nexus = tpg->tpg_nexus;
2165         if (!tv_nexus) {
2166                 mutex_unlock(&tpg->tv_tpg_mutex);
2167                 return -ENODEV;
2168         }
2169         ret = sysfs_emit(page, "%s\n",
2170                         tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
2171         mutex_unlock(&tpg->tv_tpg_mutex);
2172
2173         return ret;
2174 }
2175
2176 static ssize_t vhost_scsi_tpg_nexus_store(struct config_item *item,
2177                 const char *page, size_t count)
2178 {
2179         struct se_portal_group *se_tpg = to_tpg(item);
2180         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2181                                 struct vhost_scsi_tpg, se_tpg);
2182         struct vhost_scsi_tport *tport_wwn = tpg->tport;
2183         unsigned char i_port[VHOST_SCSI_NAMELEN], *ptr, *port_ptr;
2184         int ret;
2185         /*
2186          * Shutdown the active I_T nexus if 'NULL' is passed..
2187          */
2188         if (!strncmp(page, "NULL", 4)) {
2189                 ret = vhost_scsi_drop_nexus(tpg);
2190                 return (!ret) ? count : ret;
2191         }
2192         /*
2193          * Otherwise make sure the passed virtual Initiator port WWN matches
2194          * the fabric protocol_id set in vhost_scsi_make_tport(), and call
2195          * vhost_scsi_make_nexus().
2196          */
2197         if (strlen(page) >= VHOST_SCSI_NAMELEN) {
2198                 pr_err("Emulated NAA Sas Address: %s, exceeds"
2199                                 " max: %d\n", page, VHOST_SCSI_NAMELEN);
2200                 return -EINVAL;
2201         }
2202         snprintf(&i_port[0], VHOST_SCSI_NAMELEN, "%s", page);
2203
2204         ptr = strstr(i_port, "naa.");
2205         if (ptr) {
2206                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
2207                         pr_err("Passed SAS Initiator Port %s does not"
2208                                 " match target port protoid: %s\n", i_port,
2209                                 vhost_scsi_dump_proto_id(tport_wwn));
2210                         return -EINVAL;
2211                 }
2212                 port_ptr = &i_port[0];
2213                 goto check_newline;
2214         }
2215         ptr = strstr(i_port, "fc.");
2216         if (ptr) {
2217                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
2218                         pr_err("Passed FCP Initiator Port %s does not"
2219                                 " match target port protoid: %s\n", i_port,
2220                                 vhost_scsi_dump_proto_id(tport_wwn));
2221                         return -EINVAL;
2222                 }
2223                 port_ptr = &i_port[3]; /* Skip over "fc." */
2224                 goto check_newline;
2225         }
2226         ptr = strstr(i_port, "iqn.");
2227         if (ptr) {
2228                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
2229                         pr_err("Passed iSCSI Initiator Port %s does not"
2230                                 " match target port protoid: %s\n", i_port,
2231                                 vhost_scsi_dump_proto_id(tport_wwn));
2232                         return -EINVAL;
2233                 }
2234                 port_ptr = &i_port[0];
2235                 goto check_newline;
2236         }
2237         pr_err("Unable to locate prefix for emulated Initiator Port:"
2238                         " %s\n", i_port);
2239         return -EINVAL;
2240         /*
2241          * Clear any trailing newline for the NAA WWN
2242          */
2243 check_newline:
2244         if (i_port[strlen(i_port)-1] == '\n')
2245                 i_port[strlen(i_port)-1] = '\0';
2246
2247         ret = vhost_scsi_make_nexus(tpg, port_ptr);
2248         if (ret < 0)
2249                 return ret;
2250
2251         return count;
2252 }
2253
2254 CONFIGFS_ATTR(vhost_scsi_tpg_, nexus);
2255
2256 static struct configfs_attribute *vhost_scsi_tpg_attrs[] = {
2257         &vhost_scsi_tpg_attr_nexus,
2258         NULL,
2259 };
2260
2261 static struct se_portal_group *
2262 vhost_scsi_make_tpg(struct se_wwn *wwn, const char *name)
2263 {
2264         struct vhost_scsi_tport *tport = container_of(wwn,
2265                         struct vhost_scsi_tport, tport_wwn);
2266
2267         struct vhost_scsi_tpg *tpg;
2268         u16 tpgt;
2269         int ret;
2270
2271         if (strstr(name, "tpgt_") != name)
2272                 return ERR_PTR(-EINVAL);
2273         if (kstrtou16(name + 5, 10, &tpgt) || tpgt >= VHOST_SCSI_MAX_TARGET)
2274                 return ERR_PTR(-EINVAL);
2275
2276         tpg = kzalloc(sizeof(*tpg), GFP_KERNEL);
2277         if (!tpg) {
2278                 pr_err("Unable to allocate struct vhost_scsi_tpg");
2279                 return ERR_PTR(-ENOMEM);
2280         }
2281         mutex_init(&tpg->tv_tpg_mutex);
2282         INIT_LIST_HEAD(&tpg->tv_tpg_list);
2283         tpg->tport = tport;
2284         tpg->tport_tpgt = tpgt;
2285
2286         ret = core_tpg_register(wwn, &tpg->se_tpg, tport->tport_proto_id);
2287         if (ret < 0) {
2288                 kfree(tpg);
2289                 return NULL;
2290         }
2291         mutex_lock(&vhost_scsi_mutex);
2292         list_add_tail(&tpg->tv_tpg_list, &vhost_scsi_list);
2293         mutex_unlock(&vhost_scsi_mutex);
2294
2295         return &tpg->se_tpg;
2296 }
2297
2298 static void vhost_scsi_drop_tpg(struct se_portal_group *se_tpg)
2299 {
2300         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2301                                 struct vhost_scsi_tpg, se_tpg);
2302
2303         mutex_lock(&vhost_scsi_mutex);
2304         list_del(&tpg->tv_tpg_list);
2305         mutex_unlock(&vhost_scsi_mutex);
2306         /*
2307          * Release the virtual I_T Nexus for this vhost TPG
2308          */
2309         vhost_scsi_drop_nexus(tpg);
2310         /*
2311          * Deregister the se_tpg from TCM..
2312          */
2313         core_tpg_deregister(se_tpg);
2314         kfree(tpg);
2315 }
2316
2317 static struct se_wwn *
2318 vhost_scsi_make_tport(struct target_fabric_configfs *tf,
2319                      struct config_group *group,
2320                      const char *name)
2321 {
2322         struct vhost_scsi_tport *tport;
2323         char *ptr;
2324         u64 wwpn = 0;
2325         int off = 0;
2326
2327         /* if (vhost_scsi_parse_wwn(name, &wwpn, 1) < 0)
2328                 return ERR_PTR(-EINVAL); */
2329
2330         tport = kzalloc(sizeof(*tport), GFP_KERNEL);
2331         if (!tport) {
2332                 pr_err("Unable to allocate struct vhost_scsi_tport");
2333                 return ERR_PTR(-ENOMEM);
2334         }
2335         tport->tport_wwpn = wwpn;
2336         /*
2337          * Determine the emulated Protocol Identifier and Target Port Name
2338          * based on the incoming configfs directory name.
2339          */
2340         ptr = strstr(name, "naa.");
2341         if (ptr) {
2342                 tport->tport_proto_id = SCSI_PROTOCOL_SAS;
2343                 goto check_len;
2344         }
2345         ptr = strstr(name, "fc.");
2346         if (ptr) {
2347                 tport->tport_proto_id = SCSI_PROTOCOL_FCP;
2348                 off = 3; /* Skip over "fc." */
2349                 goto check_len;
2350         }
2351         ptr = strstr(name, "iqn.");
2352         if (ptr) {
2353                 tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
2354                 goto check_len;
2355         }
2356
2357         pr_err("Unable to locate prefix for emulated Target Port:"
2358                         " %s\n", name);
2359         kfree(tport);
2360         return ERR_PTR(-EINVAL);
2361
2362 check_len:
2363         if (strlen(name) >= VHOST_SCSI_NAMELEN) {
2364                 pr_err("Emulated %s Address: %s, exceeds"
2365                         " max: %d\n", name, vhost_scsi_dump_proto_id(tport),
2366                         VHOST_SCSI_NAMELEN);
2367                 kfree(tport);
2368                 return ERR_PTR(-EINVAL);
2369         }
2370         snprintf(&tport->tport_name[0], VHOST_SCSI_NAMELEN, "%s", &name[off]);
2371
2372         pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target"
2373                 " %s Address: %s\n", vhost_scsi_dump_proto_id(tport), name);
2374
2375         return &tport->tport_wwn;
2376 }
2377
2378 static void vhost_scsi_drop_tport(struct se_wwn *wwn)
2379 {
2380         struct vhost_scsi_tport *tport = container_of(wwn,
2381                                 struct vhost_scsi_tport, tport_wwn);
2382
2383         pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target"
2384                 " %s Address: %s\n", vhost_scsi_dump_proto_id(tport),
2385                 tport->tport_name);
2386
2387         kfree(tport);
2388 }
2389
2390 static ssize_t
2391 vhost_scsi_wwn_version_show(struct config_item *item, char *page)
2392 {
2393         return sysfs_emit(page, "TCM_VHOST fabric module %s on %s/%s"
2394                 "on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
2395                 utsname()->machine);
2396 }
2397
2398 CONFIGFS_ATTR_RO(vhost_scsi_wwn_, version);
2399
2400 static struct configfs_attribute *vhost_scsi_wwn_attrs[] = {
2401         &vhost_scsi_wwn_attr_version,
2402         NULL,
2403 };
2404
2405 static const struct target_core_fabric_ops vhost_scsi_ops = {
2406         .module                         = THIS_MODULE,
2407         .fabric_name                    = "vhost",
2408         .max_data_sg_nents              = VHOST_SCSI_PREALLOC_SGLS,
2409         .tpg_get_wwn                    = vhost_scsi_get_fabric_wwn,
2410         .tpg_get_tag                    = vhost_scsi_get_tpgt,
2411         .tpg_check_demo_mode            = vhost_scsi_check_true,
2412         .tpg_check_demo_mode_cache      = vhost_scsi_check_true,
2413         .tpg_check_prot_fabric_only     = vhost_scsi_check_prot_fabric_only,
2414         .release_cmd                    = vhost_scsi_release_cmd,
2415         .check_stop_free                = vhost_scsi_check_stop_free,
2416         .sess_get_initiator_sid         = NULL,
2417         .write_pending                  = vhost_scsi_write_pending,
2418         .queue_data_in                  = vhost_scsi_queue_data_in,
2419         .queue_status                   = vhost_scsi_queue_status,
2420         .queue_tm_rsp                   = vhost_scsi_queue_tm_rsp,
2421         .aborted_task                   = vhost_scsi_aborted_task,
2422         /*
2423          * Setup callers for generic logic in target_core_fabric_configfs.c
2424          */
2425         .fabric_make_wwn                = vhost_scsi_make_tport,
2426         .fabric_drop_wwn                = vhost_scsi_drop_tport,
2427         .fabric_make_tpg                = vhost_scsi_make_tpg,
2428         .fabric_drop_tpg                = vhost_scsi_drop_tpg,
2429         .fabric_post_link               = vhost_scsi_port_link,
2430         .fabric_pre_unlink              = vhost_scsi_port_unlink,
2431
2432         .tfc_wwn_attrs                  = vhost_scsi_wwn_attrs,
2433         .tfc_tpg_base_attrs             = vhost_scsi_tpg_attrs,
2434         .tfc_tpg_attrib_attrs           = vhost_scsi_tpg_attrib_attrs,
2435 };
2436
2437 static int __init vhost_scsi_init(void)
2438 {
2439         int ret = -ENOMEM;
2440
2441         pr_debug("TCM_VHOST fabric module %s on %s/%s"
2442                 " on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
2443                 utsname()->machine);
2444
2445         ret = vhost_scsi_register();
2446         if (ret < 0)
2447                 goto out;
2448
2449         ret = target_register_template(&vhost_scsi_ops);
2450         if (ret < 0)
2451                 goto out_vhost_scsi_deregister;
2452
2453         return 0;
2454
2455 out_vhost_scsi_deregister:
2456         vhost_scsi_deregister();
2457 out:
2458         return ret;
2459 };
2460
2461 static void vhost_scsi_exit(void)
2462 {
2463         target_unregister_template(&vhost_scsi_ops);
2464         vhost_scsi_deregister();
2465 };
2466
2467 MODULE_DESCRIPTION("VHOST_SCSI series fabric driver");
2468 MODULE_ALIAS("tcm_vhost");
2469 MODULE_LICENSE("GPL");
2470 module_init(vhost_scsi_init);
2471 module_exit(vhost_scsi_exit);