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 int vhost_scsi_check_false(struct se_portal_group *se_tpg)
 295 {
 296         return 0;
 297 }
 298
 299 static char *vhost_scsi_get_fabric_wwn(struct se_portal_group *se_tpg)
 300 {
 301         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 302                                 struct vhost_scsi_tpg, se_tpg);
 303         struct vhost_scsi_tport *tport = tpg->tport;
 304
 305         return &tport->tport_name[0];
 306 }
 307
 308 static u16 vhost_scsi_get_tpgt(struct se_portal_group *se_tpg)
 309 {
 310         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 311                                 struct vhost_scsi_tpg, se_tpg);
 312         return tpg->tport_tpgt;
 313 }
 314
 315 static int vhost_scsi_check_prot_fabric_only(struct se_portal_group *se_tpg)
 316 {
 317         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 318                                 struct vhost_scsi_tpg, se_tpg);
 319
 320         return tpg->tv_fabric_prot_type;
 321 }
 322
 323 static u32 vhost_scsi_tpg_get_inst_index(struct se_portal_group *se_tpg)
 324 {
 325         return 1;
 326 }
 327
 328 static void vhost_scsi_release_cmd_res(struct se_cmd *se_cmd)
 329 {
 330         struct vhost_scsi_cmd *tv_cmd = container_of(se_cmd,
 331                                 struct vhost_scsi_cmd, tvc_se_cmd);
 332         struct vhost_scsi_virtqueue *svq = container_of(tv_cmd->tvc_vq,
 333                                 struct vhost_scsi_virtqueue, vq);
 334         struct vhost_scsi_inflight *inflight = tv_cmd->inflight;
 335         int i;
 336
 337         if (tv_cmd->tvc_sgl_count) {
 338                 for (i = 0; i < tv_cmd->tvc_sgl_count; i++)
 339                         put_page(sg_page(&tv_cmd->tvc_sgl[i]));
 340         }
 341         if (tv_cmd->tvc_prot_sgl_count) {
 342                 for (i = 0; i < tv_cmd->tvc_prot_sgl_count; i++)
 343                         put_page(sg_page(&tv_cmd->tvc_prot_sgl[i]));
 344         }
 345
 346         sbitmap_clear_bit(&svq->scsi_tags, se_cmd->map_tag);
 347         vhost_scsi_put_inflight(inflight);
 348 }
 349
 350 static void vhost_scsi_release_tmf_res(struct vhost_scsi_tmf *tmf)
 351 {
 352         struct vhost_scsi_inflight *inflight = tmf->inflight;
 353
 354         kfree(tmf);
 355         vhost_scsi_put_inflight(inflight);
 356 }
 357
 358 static void vhost_scsi_release_cmd(struct se_cmd *se_cmd)
 359 {
 360         if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB) {
 361                 struct vhost_scsi_tmf *tmf = container_of(se_cmd,
 362                                         struct vhost_scsi_tmf, se_cmd);
 363
 364                 vhost_work_queue(&tmf->vhost->dev, &tmf->vwork);
 365         } else {
 366                 struct vhost_scsi_cmd *cmd = container_of(se_cmd,
 367                                         struct vhost_scsi_cmd, tvc_se_cmd);
 368                 struct vhost_scsi *vs = cmd->tvc_vhost;
 369
 370                 llist_add(&cmd->tvc_completion_list, &vs->vs_completion_list);
 371                 vhost_work_queue(&vs->dev, &vs->vs_completion_work);
 372         }
 373 }
 374
 375 static u32 vhost_scsi_sess_get_index(struct se_session *se_sess)
 376 {
 377         return 0;
 378 }
 379
 380 static int vhost_scsi_write_pending(struct se_cmd *se_cmd)
 381 {
 382         /* Go ahead and process the write immediately */
 383         target_execute_cmd(se_cmd);
 384         return 0;
 385 }
 386
 387 static void vhost_scsi_set_default_node_attrs(struct se_node_acl *nacl)
 388 {
 389         return;
 390 }
 391
 392 static int vhost_scsi_get_cmd_state(struct se_cmd *se_cmd)
 393 {
 394         return 0;
 395 }
 396
 397 static int vhost_scsi_queue_data_in(struct se_cmd *se_cmd)
 398 {
 399         transport_generic_free_cmd(se_cmd, 0);
 400         return 0;
 401 }
 402
 403 static int vhost_scsi_queue_status(struct se_cmd *se_cmd)
 404 {
 405         transport_generic_free_cmd(se_cmd, 0);
 406         return 0;
 407 }
 408
 409 static void vhost_scsi_queue_tm_rsp(struct se_cmd *se_cmd)
 410 {
 411         struct vhost_scsi_tmf *tmf = container_of(se_cmd, struct vhost_scsi_tmf,
 412                                                   se_cmd);
 413
 414         tmf->scsi_resp = se_cmd->se_tmr_req->response;
 415         transport_generic_free_cmd(&tmf->se_cmd, 0);
 416 }
 417
 418 static void vhost_scsi_aborted_task(struct se_cmd *se_cmd)
 419 {
 420         return;
 421 }
 422
 423 static void vhost_scsi_free_evt(struct vhost_scsi *vs, struct vhost_scsi_evt *evt)
 424 {
 425         vs->vs_events_nr--;
 426         kfree(evt);
 427 }
 428
 429 static struct vhost_scsi_evt *
 430 vhost_scsi_allocate_evt(struct vhost_scsi *vs,
 431                        u32 event, u32 reason)
 432 {
 433         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 434         struct vhost_scsi_evt *evt;
 435
 436         if (vs->vs_events_nr > VHOST_SCSI_MAX_EVENT) {
 437                 vs->vs_events_missed = true;
 438                 return NULL;
 439         }
 440
 441         evt = kzalloc(sizeof(*evt), GFP_KERNEL);
 442         if (!evt) {
 443                 vq_err(vq, "Failed to allocate vhost_scsi_evt\n");
 444                 vs->vs_events_missed = true;
 445                 return NULL;
 446         }
 447
 448         evt->event.event = cpu_to_vhost32(vq, event);
 449         evt->event.reason = cpu_to_vhost32(vq, reason);
 450         vs->vs_events_nr++;
 451
 452         return evt;
 453 }
 454
 455 static int vhost_scsi_check_stop_free(struct se_cmd *se_cmd)
 456 {
 457         return target_put_sess_cmd(se_cmd);
 458 }
 459
 460 static void
 461 vhost_scsi_do_evt_work(struct vhost_scsi *vs, struct vhost_scsi_evt *evt)
 462 {
 463         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 464         struct virtio_scsi_event *event = &evt->event;
 465         struct virtio_scsi_event __user *eventp;
 466         unsigned out, in;
 467         int head, ret;
 468
 469         if (!vhost_vq_get_backend(vq)) {
 470                 vs->vs_events_missed = true;
 471                 return;
 472         }
 473
 474 again:
 475         vhost_disable_notify(&vs->dev, vq);
 476         head = vhost_get_vq_desc(vq, vq->iov,
 477                         ARRAY_SIZE(vq->iov), &out, &in,
 478                         NULL, NULL);
 479         if (head < 0) {
 480                 vs->vs_events_missed = true;
 481                 return;
 482         }
 483         if (head == vq->num) {
 484                 if (vhost_enable_notify(&vs->dev, vq))
 485                         goto again;
 486                 vs->vs_events_missed = true;
 487                 return;
 488         }
 489
 490         if ((vq->iov[out].iov_len != sizeof(struct virtio_scsi_event))) {
 491                 vq_err(vq, "Expecting virtio_scsi_event, got %zu bytes\n",
 492                                 vq->iov[out].iov_len);
 493                 vs->vs_events_missed = true;
 494                 return;
 495         }
 496
 497         if (vs->vs_events_missed) {
 498                 event->event |= cpu_to_vhost32(vq, VIRTIO_SCSI_T_EVENTS_MISSED);
 499                 vs->vs_events_missed = false;
 500         }
 501
 502         eventp = vq->iov[out].iov_base;
 503         ret = __copy_to_user(eventp, event, sizeof(*event));
 504         if (!ret)
 505                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 506         else
 507                 vq_err(vq, "Faulted on vhost_scsi_send_event\n");
 508 }
 509
 510 static void vhost_scsi_evt_work(struct vhost_work *work)
 511 {
 512         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 513                                         vs_event_work);
 514         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 515         struct vhost_scsi_evt *evt, *t;
 516         struct llist_node *llnode;
 517
 518         mutex_lock(&vq->mutex);
 519         llnode = llist_del_all(&vs->vs_event_list);
 520         llist_for_each_entry_safe(evt, t, llnode, list) {
 521                 vhost_scsi_do_evt_work(vs, evt);
 522                 vhost_scsi_free_evt(vs, evt);
 523         }
 524         mutex_unlock(&vq->mutex);
 525 }
 526
 527 /* Fill in status and signal that we are done processing this command
 528  *
 529  * This is scheduled in the vhost work queue so we are called with the owner
 530  * process mm and can access the vring.
 531  */
 532 static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
 533 {
 534         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 535                                         vs_completion_work);
 536         struct virtio_scsi_cmd_resp v_rsp;
 537         struct vhost_scsi_cmd *cmd, *t;
 538         struct llist_node *llnode;
 539         struct se_cmd *se_cmd;
 540         struct iov_iter iov_iter;
 541         int ret, vq;
 542
 543         bitmap_zero(vs->compl_bitmap, vs->dev.nvqs);
 544         llnode = llist_del_all(&vs->vs_completion_list);
 545         llist_for_each_entry_safe(cmd, t, llnode, tvc_completion_list) {
 546                 se_cmd = &cmd->tvc_se_cmd;
 547
 548                 pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__,
 549                         cmd, se_cmd->residual_count, se_cmd->scsi_status);
 550
 551                 memset(&v_rsp, 0, sizeof(v_rsp));
 552                 v_rsp.resid = cpu_to_vhost32(cmd->tvc_vq, se_cmd->residual_count);
 553                 /* TODO is status_qualifier field needed? */
 554                 v_rsp.status = se_cmd->scsi_status;
 555                 v_rsp.sense_len = cpu_to_vhost32(cmd->tvc_vq,
 556                                                  se_cmd->scsi_sense_length);
 557                 memcpy(v_rsp.sense, cmd->tvc_sense_buf,
 558                        se_cmd->scsi_sense_length);
 559
 560                 iov_iter_init(&iov_iter, ITER_DEST, cmd->tvc_resp_iov,
 561                               cmd->tvc_in_iovs, sizeof(v_rsp));
 562                 ret = copy_to_iter(&v_rsp, sizeof(v_rsp), &iov_iter);
 563                 if (likely(ret == sizeof(v_rsp))) {
 564                         struct vhost_scsi_virtqueue *q;
 565                         vhost_add_used(cmd->tvc_vq, cmd->tvc_vq_desc, 0);
 566                         q = container_of(cmd->tvc_vq, struct vhost_scsi_virtqueue, vq);
 567                         vq = q - vs->vqs;
 568                         __set_bit(vq, vs->compl_bitmap);
 569                 } else
 570                         pr_err("Faulted on virtio_scsi_cmd_resp\n");
 571
 572                 vhost_scsi_release_cmd_res(se_cmd);
 573         }
 574
 575         vq = -1;
 576         while ((vq = find_next_bit(vs->compl_bitmap, vs->dev.nvqs, vq + 1))
 577                 < vs->dev.nvqs)
 578                 vhost_signal(&vs->dev, &vs->vqs[vq].vq);
 579 }
 580
 581 static struct vhost_scsi_cmd *
 582 vhost_scsi_get_cmd(struct vhost_virtqueue *vq, struct vhost_scsi_tpg *tpg,
 583                    unsigned char *cdb, u64 scsi_tag, u16 lun, u8 task_attr,
 584                    u32 exp_data_len, int data_direction)
 585 {
 586         struct vhost_scsi_virtqueue *svq = container_of(vq,
 587                                         struct vhost_scsi_virtqueue, vq);
 588         struct vhost_scsi_cmd *cmd;
 589         struct vhost_scsi_nexus *tv_nexus;
 590         struct scatterlist *sg, *prot_sg;
 591         struct iovec *tvc_resp_iov;
 592         struct page **pages;
 593         int tag;
 594
 595         tv_nexus = tpg->tpg_nexus;
 596         if (!tv_nexus) {
 597                 pr_err("Unable to locate active struct vhost_scsi_nexus\n");
 598                 return ERR_PTR(-EIO);
 599         }
 600
 601         tag = sbitmap_get(&svq->scsi_tags);
 602         if (tag < 0) {
 603                 pr_err("Unable to obtain tag for vhost_scsi_cmd\n");
 604                 return ERR_PTR(-ENOMEM);
 605         }
 606
 607         cmd = &svq->scsi_cmds[tag];
 608         sg = cmd->tvc_sgl;
 609         prot_sg = cmd->tvc_prot_sgl;
 610         pages = cmd->tvc_upages;
 611         tvc_resp_iov = cmd->tvc_resp_iov;
 612         memset(cmd, 0, sizeof(*cmd));
 613         cmd->tvc_sgl = sg;
 614         cmd->tvc_prot_sgl = prot_sg;
 615         cmd->tvc_upages = pages;
 616         cmd->tvc_se_cmd.map_tag = tag;
 617         cmd->tvc_tag = scsi_tag;
 618         cmd->tvc_lun = lun;
 619         cmd->tvc_task_attr = task_attr;
 620         cmd->tvc_exp_data_len = exp_data_len;
 621         cmd->tvc_data_direction = data_direction;
 622         cmd->tvc_nexus = tv_nexus;
 623         cmd->inflight = vhost_scsi_get_inflight(vq);
 624         cmd->tvc_resp_iov = tvc_resp_iov;
 625
 626         memcpy(cmd->tvc_cdb, cdb, VHOST_SCSI_MAX_CDB_SIZE);
 627
 628         return cmd;
 629 }
 630
 631 /*
 632  * Map a user memory range into a scatterlist
 633  *
 634  * Returns the number of scatterlist entries used or -errno on error.
 635  */
 636 static int
 637 vhost_scsi_map_to_sgl(struct vhost_scsi_cmd *cmd,
 638                       struct iov_iter *iter,
 639                       struct scatterlist *sgl,
 640                       bool write)
 641 {
 642         struct page **pages = cmd->tvc_upages;
 643         struct scatterlist *sg = sgl;
 644         ssize_t bytes;
 645         size_t offset;
 646         unsigned int npages = 0;
 647
 648         bytes = iov_iter_get_pages2(iter, pages, LONG_MAX,
 649                                 VHOST_SCSI_PREALLOC_UPAGES, &offset);
 650         /* No pages were pinned */
 651         if (bytes <= 0)
 652                 return bytes < 0 ? bytes : -EFAULT;
 653
 654         while (bytes) {
 655                 unsigned n = min_t(unsigned, PAGE_SIZE - offset, bytes);
 656                 sg_set_page(sg++, pages[npages++], n, offset);
 657                 bytes -= n;
 658                 offset = 0;
 659         }
 660         return npages;
 661 }
 662
 663 static int
 664 vhost_scsi_calc_sgls(struct iov_iter *iter, size_t bytes, int max_sgls)
 665 {
 666         int sgl_count = 0;
 667
 668         if (!iter || !iter->iov) {
 669                 pr_err("%s: iter->iov is NULL, but expected bytes: %zu"
 670                        " present\n", __func__, bytes);
 671                 return -EINVAL;
 672         }
 673
 674         sgl_count = iov_iter_npages(iter, 0xffff);
 675         if (sgl_count > max_sgls) {
 676                 pr_err("%s: requested sgl_count: %d exceeds pre-allocated"
 677                        " max_sgls: %d\n", __func__, sgl_count, max_sgls);
 678                 return -EINVAL;
 679         }
 680         return sgl_count;
 681 }
 682
 683 static int
 684 vhost_scsi_iov_to_sgl(struct vhost_scsi_cmd *cmd, bool write,
 685                       struct iov_iter *iter,
 686                       struct scatterlist *sg, int sg_count)
 687 {
 688         struct scatterlist *p = sg;
 689         int ret;
 690
 691         while (iov_iter_count(iter)) {
 692                 ret = vhost_scsi_map_to_sgl(cmd, iter, sg, write);
 693                 if (ret < 0) {
 694                         while (p < sg) {
 695                                 struct page *page = sg_page(p++);
 696                                 if (page)
 697                                         put_page(page);
 698                         }
 699                         return ret;
 700                 }
 701                 sg += ret;
 702         }
 703         return 0;
 704 }
 705
 706 static int
 707 vhost_scsi_mapal(struct vhost_scsi_cmd *cmd,
 708                  size_t prot_bytes, struct iov_iter *prot_iter,
 709                  size_t data_bytes, struct iov_iter *data_iter)
 710 {
 711         int sgl_count, ret;
 712         bool write = (cmd->tvc_data_direction == DMA_FROM_DEVICE);
 713
 714         if (prot_bytes) {
 715                 sgl_count = vhost_scsi_calc_sgls(prot_iter, prot_bytes,
 716                                                  VHOST_SCSI_PREALLOC_PROT_SGLS);
 717                 if (sgl_count < 0)
 718                         return sgl_count;
 719
 720                 sg_init_table(cmd->tvc_prot_sgl, sgl_count);
 721                 cmd->tvc_prot_sgl_count = sgl_count;
 722                 pr_debug("%s prot_sg %p prot_sgl_count %u\n", __func__,
 723                          cmd->tvc_prot_sgl, cmd->tvc_prot_sgl_count);
 724
 725                 ret = vhost_scsi_iov_to_sgl(cmd, write, prot_iter,
 726                                             cmd->tvc_prot_sgl,
 727                                             cmd->tvc_prot_sgl_count);
 728                 if (ret < 0) {
 729                         cmd->tvc_prot_sgl_count = 0;
 730                         return ret;
 731                 }
 732         }
 733         sgl_count = vhost_scsi_calc_sgls(data_iter, data_bytes,
 734                                          VHOST_SCSI_PREALLOC_SGLS);
 735         if (sgl_count < 0)
 736                 return sgl_count;
 737
 738         sg_init_table(cmd->tvc_sgl, sgl_count);
 739         cmd->tvc_sgl_count = sgl_count;
 740         pr_debug("%s data_sg %p data_sgl_count %u\n", __func__,
 741                   cmd->tvc_sgl, cmd->tvc_sgl_count);
 742
 743         ret = vhost_scsi_iov_to_sgl(cmd, write, data_iter,
 744                                     cmd->tvc_sgl, cmd->tvc_sgl_count);
 745         if (ret < 0) {
 746                 cmd->tvc_sgl_count = 0;
 747                 return ret;
 748         }
 749         return 0;
 750 }
 751
 752 static int vhost_scsi_to_tcm_attr(int attr)
 753 {
 754         switch (attr) {
 755         case VIRTIO_SCSI_S_SIMPLE:
 756                 return TCM_SIMPLE_TAG;
 757         case VIRTIO_SCSI_S_ORDERED:
 758                 return TCM_ORDERED_TAG;
 759         case VIRTIO_SCSI_S_HEAD:
 760                 return TCM_HEAD_TAG;
 761         case VIRTIO_SCSI_S_ACA:
 762                 return TCM_ACA_TAG;
 763         default:
 764                 break;
 765         }
 766         return TCM_SIMPLE_TAG;
 767 }
 768
 769 static void vhost_scsi_target_queue_cmd(struct vhost_scsi_cmd *cmd)
 770 {
 771         struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
 772         struct vhost_scsi_nexus *tv_nexus;
 773         struct scatterlist *sg_ptr, *sg_prot_ptr = NULL;
 774
 775         /* FIXME: BIDI operation */
 776         if (cmd->tvc_sgl_count) {
 777                 sg_ptr = cmd->tvc_sgl;
 778
 779                 if (cmd->tvc_prot_sgl_count)
 780                         sg_prot_ptr = cmd->tvc_prot_sgl;
 781                 else
 782                         se_cmd->prot_pto = true;
 783         } else {
 784                 sg_ptr = NULL;
 785         }
 786         tv_nexus = cmd->tvc_nexus;
 787
 788         se_cmd->tag = 0;
 789         target_init_cmd(se_cmd, tv_nexus->tvn_se_sess, &cmd->tvc_sense_buf[0],
 790                         cmd->tvc_lun, cmd->tvc_exp_data_len,
 791                         vhost_scsi_to_tcm_attr(cmd->tvc_task_attr),
 792                         cmd->tvc_data_direction, TARGET_SCF_ACK_KREF);
 793
 794         if (target_submit_prep(se_cmd, cmd->tvc_cdb, sg_ptr,
 795                                cmd->tvc_sgl_count, NULL, 0, sg_prot_ptr,
 796                                cmd->tvc_prot_sgl_count, GFP_KERNEL))
 797                 return;
 798
 799         target_queue_submission(se_cmd);
 800 }
 801
 802 static void
 803 vhost_scsi_send_bad_target(struct vhost_scsi *vs,
 804                            struct vhost_virtqueue *vq,
 805                            int head, unsigned out)
 806 {
 807         struct virtio_scsi_cmd_resp __user *resp;
 808         struct virtio_scsi_cmd_resp rsp;
 809         int ret;
 810
 811         memset(&rsp, 0, sizeof(rsp));
 812         rsp.response = VIRTIO_SCSI_S_BAD_TARGET;
 813         resp = vq->iov[out].iov_base;
 814         ret = __copy_to_user(resp, &rsp, sizeof(rsp));
 815         if (!ret)
 816                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 817         else
 818                 pr_err("Faulted on virtio_scsi_cmd_resp\n");
 819 }
 820
 821 static int
 822 vhost_scsi_get_desc(struct vhost_scsi *vs, struct vhost_virtqueue *vq,
 823                     struct vhost_scsi_ctx *vc)
 824 {
 825         int ret = -ENXIO;
 826
 827         vc->head = vhost_get_vq_desc(vq, vq->iov,
 828                                      ARRAY_SIZE(vq->iov), &vc->out, &vc->in,
 829                                      NULL, NULL);
 830
 831         pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n",
 832                  vc->head, vc->out, vc->in);
 833
 834         /* On error, stop handling until the next kick. */
 835         if (unlikely(vc->head < 0))
 836                 goto done;
 837
 838         /* Nothing new?  Wait for eventfd to tell us they refilled. */
 839         if (vc->head == vq->num) {
 840                 if (unlikely(vhost_enable_notify(&vs->dev, vq))) {
 841                         vhost_disable_notify(&vs->dev, vq);
 842                         ret = -EAGAIN;
 843                 }
 844                 goto done;
 845         }
 846
 847         /*
 848          * Get the size of request and response buffers.
 849          * FIXME: Not correct for BIDI operation
 850          */
 851         vc->out_size = iov_length(vq->iov, vc->out);
 852         vc->in_size = iov_length(&vq->iov[vc->out], vc->in);
 853
 854         /*
 855          * Copy over the virtio-scsi request header, which for a
 856          * ANY_LAYOUT enabled guest may span multiple iovecs, or a
 857          * single iovec may contain both the header + outgoing
 858          * WRITE payloads.
 859          *
 860          * copy_from_iter() will advance out_iter, so that it will
 861          * point at the start of the outgoing WRITE payload, if
 862          * DMA_TO_DEVICE is set.
 863          */
 864         iov_iter_init(&vc->out_iter, ITER_SOURCE, vq->iov, vc->out, vc->out_size);
 865         ret = 0;
 866
 867 done:
 868         return ret;
 869 }
 870
 871 static int
 872 vhost_scsi_chk_size(struct vhost_virtqueue *vq, struct vhost_scsi_ctx *vc)
 873 {
 874         if (unlikely(vc->in_size < vc->rsp_size)) {
 875                 vq_err(vq,
 876                        "Response buf too small, need min %zu bytes got %zu",
 877                        vc->rsp_size, vc->in_size);
 878                 return -EINVAL;
 879         } else if (unlikely(vc->out_size < vc->req_size)) {
 880                 vq_err(vq,
 881                        "Request buf too small, need min %zu bytes got %zu",
 882                        vc->req_size, vc->out_size);
 883                 return -EIO;
 884         }
 885
 886         return 0;
 887 }
 888
 889 static int
 890 vhost_scsi_get_req(struct vhost_virtqueue *vq, struct vhost_scsi_ctx *vc,
 891                    struct vhost_scsi_tpg **tpgp)
 892 {
 893         int ret = -EIO;
 894
 895         if (unlikely(!copy_from_iter_full(vc->req, vc->req_size,
 896                                           &vc->out_iter))) {
 897                 vq_err(vq, "Faulted on copy_from_iter_full\n");
 898         } else if (unlikely(*vc->lunp != 1)) {
 899                 /* virtio-scsi spec requires byte 0 of the lun to be 1 */
 900                 vq_err(vq, "Illegal virtio-scsi lun: %u\n", *vc->lunp);
 901         } else {
 902                 struct vhost_scsi_tpg **vs_tpg, *tpg;
 903
 904                 vs_tpg = vhost_vq_get_backend(vq);      /* validated at handler entry */
 905
 906                 tpg = READ_ONCE(vs_tpg[*vc->target]);
 907                 if (unlikely(!tpg)) {
 908                         vq_err(vq, "Target 0x%x does not exist\n", *vc->target);
 909                 } else {
 910                         if (tpgp)
 911                                 *tpgp = tpg;
 912                         ret = 0;
 913                 }
 914         }
 915
 916         return ret;
 917 }
 918
 919 static u16 vhost_buf_to_lun(u8 *lun_buf)
 920 {
 921         return ((lun_buf[2] << 8) | lun_buf[3]) & 0x3FFF;
 922 }
 923
 924 static void
 925 vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
 926 {
 927         struct vhost_scsi_tpg **vs_tpg, *tpg;
 928         struct virtio_scsi_cmd_req v_req;
 929         struct virtio_scsi_cmd_req_pi v_req_pi;
 930         struct vhost_scsi_ctx vc;
 931         struct vhost_scsi_cmd *cmd;
 932         struct iov_iter in_iter, prot_iter, data_iter;
 933         u64 tag;
 934         u32 exp_data_len, data_direction;
 935         int ret, prot_bytes, i, c = 0;
 936         u16 lun;
 937         u8 task_attr;
 938         bool t10_pi = vhost_has_feature(vq, VIRTIO_SCSI_F_T10_PI);
 939         void *cdb;
 940
 941         mutex_lock(&vq->mutex);
 942         /*
 943          * We can handle the vq only after the endpoint is setup by calling the
 944          * VHOST_SCSI_SET_ENDPOINT ioctl.
 945          */
 946         vs_tpg = vhost_vq_get_backend(vq);
 947         if (!vs_tpg)
 948                 goto out;
 949
 950         memset(&vc, 0, sizeof(vc));
 951         vc.rsp_size = sizeof(struct virtio_scsi_cmd_resp);
 952
 953         vhost_disable_notify(&vs->dev, vq);
 954
 955         do {
 956                 ret = vhost_scsi_get_desc(vs, vq, &vc);
 957                 if (ret)
 958                         goto err;
 959
 960                 /*
 961                  * Setup pointers and values based upon different virtio-scsi
 962                  * request header if T10_PI is enabled in KVM guest.
 963                  */
 964                 if (t10_pi) {
 965                         vc.req = &v_req_pi;
 966                         vc.req_size = sizeof(v_req_pi);
 967                         vc.lunp = &v_req_pi.lun[0];
 968                         vc.target = &v_req_pi.lun[1];
 969                 } else {
 970                         vc.req = &v_req;
 971                         vc.req_size = sizeof(v_req);
 972                         vc.lunp = &v_req.lun[0];
 973                         vc.target = &v_req.lun[1];
 974                 }
 975
 976                 /*
 977                  * Validate the size of request and response buffers.
 978                  * Check for a sane response buffer so we can report
 979                  * early errors back to the guest.
 980                  */
 981                 ret = vhost_scsi_chk_size(vq, &vc);
 982                 if (ret)
 983                         goto err;
 984
 985                 ret = vhost_scsi_get_req(vq, &vc, &tpg);
 986                 if (ret)
 987                         goto err;
 988
 989                 ret = -EIO;     /* bad target on any error from here on */
 990
 991                 /*
 992                  * Determine data_direction by calculating the total outgoing
 993                  * iovec sizes + incoming iovec sizes vs. virtio-scsi request +
 994                  * response headers respectively.
 995                  *
 996                  * For DMA_TO_DEVICE this is out_iter, which is already pointing
 997                  * to the right place.
 998                  *
 999                  * For DMA_FROM_DEVICE, the iovec will be just past the end
1000                  * of the virtio-scsi response header in either the same
1001                  * or immediately following iovec.
1002                  *
1003                  * Any associated T10_PI bytes for the outgoing / incoming
1004                  * payloads are included in calculation of exp_data_len here.
1005                  */
1006                 prot_bytes = 0;
1007
1008                 if (vc.out_size > vc.req_size) {
1009                         data_direction = DMA_TO_DEVICE;
1010                         exp_data_len = vc.out_size - vc.req_size;
1011                         data_iter = vc.out_iter;
1012                 } else if (vc.in_size > vc.rsp_size) {
1013                         data_direction = DMA_FROM_DEVICE;
1014                         exp_data_len = vc.in_size - vc.rsp_size;
1015
1016                         iov_iter_init(&in_iter, ITER_DEST, &vq->iov[vc.out], vc.in,
1017                                       vc.rsp_size + exp_data_len);
1018                         iov_iter_advance(&in_iter, vc.rsp_size);
1019                         data_iter = in_iter;
1020                 } else {
1021                         data_direction = DMA_NONE;
1022                         exp_data_len = 0;
1023                 }
1024                 /*
1025                  * If T10_PI header + payload is present, setup prot_iter values
1026                  * and recalculate data_iter for vhost_scsi_mapal() mapping to
1027                  * host scatterlists via get_user_pages_fast().
1028                  */
1029                 if (t10_pi) {
1030                         if (v_req_pi.pi_bytesout) {
1031                                 if (data_direction != DMA_TO_DEVICE) {
1032                                         vq_err(vq, "Received non zero pi_bytesout,"
1033                                                 " but wrong data_direction\n");
1034                                         goto err;
1035                                 }
1036                                 prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesout);
1037                         } else if (v_req_pi.pi_bytesin) {
1038                                 if (data_direction != DMA_FROM_DEVICE) {
1039                                         vq_err(vq, "Received non zero pi_bytesin,"
1040                                                 " but wrong data_direction\n");
1041                                         goto err;
1042                                 }
1043                                 prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesin);
1044                         }
1045                         /*
1046                          * Set prot_iter to data_iter and truncate it to
1047                          * prot_bytes, and advance data_iter past any
1048                          * preceeding prot_bytes that may be present.
1049                          *
1050                          * Also fix up the exp_data_len to reflect only the
1051                          * actual data payload length.
1052                          */
1053                         if (prot_bytes) {
1054                                 exp_data_len -= prot_bytes;
1055                                 prot_iter = data_iter;
1056                                 iov_iter_truncate(&prot_iter, prot_bytes);
1057                                 iov_iter_advance(&data_iter, prot_bytes);
1058                         }
1059                         tag = vhost64_to_cpu(vq, v_req_pi.tag);
1060                         task_attr = v_req_pi.task_attr;
1061                         cdb = &v_req_pi.cdb[0];
1062                         lun = vhost_buf_to_lun(v_req_pi.lun);
1063                 } else {
1064                         tag = vhost64_to_cpu(vq, v_req.tag);
1065                         task_attr = v_req.task_attr;
1066                         cdb = &v_req.cdb[0];
1067                         lun = vhost_buf_to_lun(v_req.lun);
1068                 }
1069                 /*
1070                  * Check that the received CDB size does not exceeded our
1071                  * hardcoded max for vhost-scsi, then get a pre-allocated
1072                  * cmd descriptor for the new virtio-scsi tag.
1073                  *
1074                  * TODO what if cdb was too small for varlen cdb header?
1075                  */
1076                 if (unlikely(scsi_command_size(cdb) > VHOST_SCSI_MAX_CDB_SIZE)) {
1077                         vq_err(vq, "Received SCSI CDB with command_size: %d that"
1078                                 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1079                                 scsi_command_size(cdb), VHOST_SCSI_MAX_CDB_SIZE);
1080                                 goto err;
1081                 }
1082                 cmd = vhost_scsi_get_cmd(vq, tpg, cdb, tag, lun, task_attr,
1083                                          exp_data_len + prot_bytes,
1084                                          data_direction);
1085                 if (IS_ERR(cmd)) {
1086                         vq_err(vq, "vhost_scsi_get_cmd failed %ld\n",
1087                                PTR_ERR(cmd));
1088                         goto err;
1089                 }
1090                 cmd->tvc_vhost = vs;
1091                 cmd->tvc_vq = vq;
1092                 for (i = 0; i < vc.in ; i++)
1093                         cmd->tvc_resp_iov[i] = vq->iov[vc.out + i];
1094                 cmd->tvc_in_iovs = vc.in;
1095
1096                 pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n",
1097                          cmd->tvc_cdb[0], cmd->tvc_lun);
1098                 pr_debug("cmd: %p exp_data_len: %d, prot_bytes: %d data_direction:"
1099                          " %d\n", cmd, exp_data_len, prot_bytes, data_direction);
1100
1101                 if (data_direction != DMA_NONE) {
1102                         if (unlikely(vhost_scsi_mapal(cmd, prot_bytes,
1103                                                       &prot_iter, exp_data_len,
1104                                                       &data_iter))) {
1105                                 vq_err(vq, "Failed to map iov to sgl\n");
1106                                 vhost_scsi_release_cmd_res(&cmd->tvc_se_cmd);
1107                                 goto err;
1108                         }
1109                 }
1110                 /*
1111                  * Save the descriptor from vhost_get_vq_desc() to be used to
1112                  * complete the virtio-scsi request in TCM callback context via
1113                  * vhost_scsi_queue_data_in() and vhost_scsi_queue_status()
1114                  */
1115                 cmd->tvc_vq_desc = vc.head;
1116                 vhost_scsi_target_queue_cmd(cmd);
1117                 ret = 0;
1118 err:
1119                 /*
1120                  * ENXIO:  No more requests, or read error, wait for next kick
1121                  * EINVAL: Invalid response buffer, drop the request
1122                  * EIO:    Respond with bad target
1123                  * EAGAIN: Pending request
1124                  */
1125                 if (ret == -ENXIO)
1126                         break;
1127                 else if (ret == -EIO)
1128                         vhost_scsi_send_bad_target(vs, vq, vc.head, vc.out);
1129         } while (likely(!vhost_exceeds_weight(vq, ++c, 0)));
1130 out:
1131         mutex_unlock(&vq->mutex);
1132 }
1133
1134 static void
1135 vhost_scsi_send_tmf_resp(struct vhost_scsi *vs, struct vhost_virtqueue *vq,
1136                          int in_iovs, int vq_desc, struct iovec *resp_iov,
1137                          int tmf_resp_code)
1138 {
1139         struct virtio_scsi_ctrl_tmf_resp rsp;
1140         struct iov_iter iov_iter;
1141         int ret;
1142
1143         pr_debug("%s\n", __func__);
1144         memset(&rsp, 0, sizeof(rsp));
1145         rsp.response = tmf_resp_code;
1146
1147         iov_iter_init(&iov_iter, ITER_DEST, resp_iov, in_iovs, sizeof(rsp));
1148
1149         ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter);
1150         if (likely(ret == sizeof(rsp)))
1151                 vhost_add_used_and_signal(&vs->dev, vq, vq_desc, 0);
1152         else
1153                 pr_err("Faulted on virtio_scsi_ctrl_tmf_resp\n");
1154 }
1155
1156 static void vhost_scsi_tmf_resp_work(struct vhost_work *work)
1157 {
1158         struct vhost_scsi_tmf *tmf = container_of(work, struct vhost_scsi_tmf,
1159                                                   vwork);
1160         int resp_code;
1161
1162         if (tmf->scsi_resp == TMR_FUNCTION_COMPLETE)
1163                 resp_code = VIRTIO_SCSI_S_FUNCTION_SUCCEEDED;
1164         else
1165                 resp_code = VIRTIO_SCSI_S_FUNCTION_REJECTED;
1166
1167         vhost_scsi_send_tmf_resp(tmf->vhost, &tmf->svq->vq, tmf->in_iovs,
1168                                  tmf->vq_desc, &tmf->resp_iov, resp_code);
1169         vhost_scsi_release_tmf_res(tmf);
1170 }
1171
1172 static void
1173 vhost_scsi_handle_tmf(struct vhost_scsi *vs, struct vhost_scsi_tpg *tpg,
1174                       struct vhost_virtqueue *vq,
1175                       struct virtio_scsi_ctrl_tmf_req *vtmf,
1176                       struct vhost_scsi_ctx *vc)
1177 {
1178         struct vhost_scsi_virtqueue *svq = container_of(vq,
1179                                         struct vhost_scsi_virtqueue, vq);
1180         struct vhost_scsi_tmf *tmf;
1181
1182         if (vhost32_to_cpu(vq, vtmf->subtype) !=
1183             VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET)
1184                 goto send_reject;
1185
1186         if (!tpg->tpg_nexus || !tpg->tpg_nexus->tvn_se_sess) {
1187                 pr_err("Unable to locate active struct vhost_scsi_nexus for LUN RESET.\n");
1188                 goto send_reject;
1189         }
1190
1191         tmf = kzalloc(sizeof(*tmf), GFP_KERNEL);
1192         if (!tmf)
1193                 goto send_reject;
1194
1195         vhost_work_init(&tmf->vwork, vhost_scsi_tmf_resp_work);
1196         tmf->vhost = vs;
1197         tmf->svq = svq;
1198         tmf->resp_iov = vq->iov[vc->out];
1199         tmf->vq_desc = vc->head;
1200         tmf->in_iovs = vc->in;
1201         tmf->inflight = vhost_scsi_get_inflight(vq);
1202
1203         if (target_submit_tmr(&tmf->se_cmd, tpg->tpg_nexus->tvn_se_sess, NULL,
1204                               vhost_buf_to_lun(vtmf->lun), NULL,
1205                               TMR_LUN_RESET, GFP_KERNEL, 0,
1206                               TARGET_SCF_ACK_KREF) < 0) {
1207                 vhost_scsi_release_tmf_res(tmf);
1208                 goto send_reject;
1209         }
1210
1211         return;
1212
1213 send_reject:
1214         vhost_scsi_send_tmf_resp(vs, vq, vc->in, vc->head, &vq->iov[vc->out],
1215                                  VIRTIO_SCSI_S_FUNCTION_REJECTED);
1216 }
1217
1218 static void
1219 vhost_scsi_send_an_resp(struct vhost_scsi *vs,
1220                         struct vhost_virtqueue *vq,
1221                         struct vhost_scsi_ctx *vc)
1222 {
1223         struct virtio_scsi_ctrl_an_resp rsp;
1224         struct iov_iter iov_iter;
1225         int ret;
1226
1227         pr_debug("%s\n", __func__);
1228         memset(&rsp, 0, sizeof(rsp));   /* event_actual = 0 */
1229         rsp.response = VIRTIO_SCSI_S_OK;
1230
1231         iov_iter_init(&iov_iter, ITER_DEST, &vq->iov[vc->out], vc->in, sizeof(rsp));
1232
1233         ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter);
1234         if (likely(ret == sizeof(rsp)))
1235                 vhost_add_used_and_signal(&vs->dev, vq, vc->head, 0);
1236         else
1237                 pr_err("Faulted on virtio_scsi_ctrl_an_resp\n");
1238 }
1239
1240 static void
1241 vhost_scsi_ctl_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
1242 {
1243         struct vhost_scsi_tpg *tpg;
1244         union {
1245                 __virtio32 type;
1246                 struct virtio_scsi_ctrl_an_req an;
1247                 struct virtio_scsi_ctrl_tmf_req tmf;
1248         } v_req;
1249         struct vhost_scsi_ctx vc;
1250         size_t typ_size;
1251         int ret, c = 0;
1252
1253         mutex_lock(&vq->mutex);
1254         /*
1255          * We can handle the vq only after the endpoint is setup by calling the
1256          * VHOST_SCSI_SET_ENDPOINT ioctl.
1257          */
1258         if (!vhost_vq_get_backend(vq))
1259                 goto out;
1260
1261         memset(&vc, 0, sizeof(vc));
1262
1263         vhost_disable_notify(&vs->dev, vq);
1264
1265         do {
1266                 ret = vhost_scsi_get_desc(vs, vq, &vc);
1267                 if (ret)
1268                         goto err;
1269
1270                 /*
1271                  * Get the request type first in order to setup
1272                  * other parameters dependent on the type.
1273                  */
1274                 vc.req = &v_req.type;
1275                 typ_size = sizeof(v_req.type);
1276
1277                 if (unlikely(!copy_from_iter_full(vc.req, typ_size,
1278                                                   &vc.out_iter))) {
1279                         vq_err(vq, "Faulted on copy_from_iter tmf type\n");
1280                         /*
1281                          * The size of the response buffer depends on the
1282                          * request type and must be validated against it.
1283                          * Since the request type is not known, don't send
1284                          * a response.
1285                          */
1286                         continue;
1287                 }
1288
1289                 switch (vhost32_to_cpu(vq, v_req.type)) {
1290                 case VIRTIO_SCSI_T_TMF:
1291                         vc.req = &v_req.tmf;
1292                         vc.req_size = sizeof(struct virtio_scsi_ctrl_tmf_req);
1293                         vc.rsp_size = sizeof(struct virtio_scsi_ctrl_tmf_resp);
1294                         vc.lunp = &v_req.tmf.lun[0];
1295                         vc.target = &v_req.tmf.lun[1];
1296                         break;
1297                 case VIRTIO_SCSI_T_AN_QUERY:
1298                 case VIRTIO_SCSI_T_AN_SUBSCRIBE:
1299                         vc.req = &v_req.an;
1300                         vc.req_size = sizeof(struct virtio_scsi_ctrl_an_req);
1301                         vc.rsp_size = sizeof(struct virtio_scsi_ctrl_an_resp);
1302                         vc.lunp = &v_req.an.lun[0];
1303                         vc.target = NULL;
1304                         break;
1305                 default:
1306                         vq_err(vq, "Unknown control request %d", v_req.type);
1307                         continue;
1308                 }
1309
1310                 /*
1311                  * Validate the size of request and response buffers.
1312                  * Check for a sane response buffer so we can report
1313                  * early errors back to the guest.
1314                  */
1315                 ret = vhost_scsi_chk_size(vq, &vc);
1316                 if (ret)
1317                         goto err;
1318
1319                 /*
1320                  * Get the rest of the request now that its size is known.
1321                  */
1322                 vc.req += typ_size;
1323                 vc.req_size -= typ_size;
1324
1325                 ret = vhost_scsi_get_req(vq, &vc, &tpg);
1326                 if (ret)
1327                         goto err;
1328
1329                 if (v_req.type == VIRTIO_SCSI_T_TMF)
1330                         vhost_scsi_handle_tmf(vs, tpg, vq, &v_req.tmf, &vc);
1331                 else
1332                         vhost_scsi_send_an_resp(vs, vq, &vc);
1333 err:
1334                 /*
1335                  * ENXIO:  No more requests, or read error, wait for next kick
1336                  * EINVAL: Invalid response buffer, drop the request
1337                  * EIO:    Respond with bad target
1338                  * EAGAIN: Pending request
1339                  */
1340                 if (ret == -ENXIO)
1341                         break;
1342                 else if (ret == -EIO)
1343                         vhost_scsi_send_bad_target(vs, vq, vc.head, vc.out);
1344         } while (likely(!vhost_exceeds_weight(vq, ++c, 0)));
1345 out:
1346         mutex_unlock(&vq->mutex);
1347 }
1348
1349 static void vhost_scsi_ctl_handle_kick(struct vhost_work *work)
1350 {
1351         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1352                                                 poll.work);
1353         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1354
1355         pr_debug("%s: The handling func for control queue.\n", __func__);
1356         vhost_scsi_ctl_handle_vq(vs, vq);
1357 }
1358
1359 static void
1360 vhost_scsi_send_evt(struct vhost_scsi *vs,
1361                    struct vhost_scsi_tpg *tpg,
1362                    struct se_lun *lun,
1363                    u32 event,
1364                    u32 reason)
1365 {
1366         struct vhost_scsi_evt *evt;
1367
1368         evt = vhost_scsi_allocate_evt(vs, event, reason);
1369         if (!evt)
1370                 return;
1371
1372         if (tpg && lun) {
1373                 /* TODO: share lun setup code with virtio-scsi.ko */
1374                 /*
1375                  * Note: evt->event is zeroed when we allocate it and
1376                  * lun[4-7] need to be zero according to virtio-scsi spec.
1377                  */
1378                 evt->event.lun[0] = 0x01;
1379                 evt->event.lun[1] = tpg->tport_tpgt;
1380                 if (lun->unpacked_lun >= 256)
1381                         evt->event.lun[2] = lun->unpacked_lun >> 8 | 0x40 ;
1382                 evt->event.lun[3] = lun->unpacked_lun & 0xFF;
1383         }
1384
1385         llist_add(&evt->list, &vs->vs_event_list);
1386         vhost_work_queue(&vs->dev, &vs->vs_event_work);
1387 }
1388
1389 static void vhost_scsi_evt_handle_kick(struct vhost_work *work)
1390 {
1391         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1392                                                 poll.work);
1393         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1394
1395         mutex_lock(&vq->mutex);
1396         if (!vhost_vq_get_backend(vq))
1397                 goto out;
1398
1399         if (vs->vs_events_missed)
1400                 vhost_scsi_send_evt(vs, NULL, NULL, VIRTIO_SCSI_T_NO_EVENT, 0);
1401 out:
1402         mutex_unlock(&vq->mutex);
1403 }
1404
1405 static void vhost_scsi_handle_kick(struct vhost_work *work)
1406 {
1407         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1408                                                 poll.work);
1409         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1410
1411         vhost_scsi_handle_vq(vs, vq);
1412 }
1413
1414 /* Callers must hold dev mutex */
1415 static void vhost_scsi_flush(struct vhost_scsi *vs)
1416 {
1417         int i;
1418
1419         /* Init new inflight and remember the old inflight */
1420         vhost_scsi_init_inflight(vs, vs->old_inflight);
1421
1422         /*
1423          * The inflight->kref was initialized to 1. We decrement it here to
1424          * indicate the start of the flush operation so that it will reach 0
1425          * when all the reqs are finished.
1426          */
1427         for (i = 0; i < vs->dev.nvqs; i++)
1428                 kref_put(&vs->old_inflight[i]->kref, vhost_scsi_done_inflight);
1429
1430         /* Flush both the vhost poll and vhost work */
1431         vhost_dev_flush(&vs->dev);
1432
1433         /* Wait for all reqs issued before the flush to be finished */
1434         for (i = 0; i < vs->dev.nvqs; i++)
1435                 wait_for_completion(&vs->old_inflight[i]->comp);
1436 }
1437
1438 static void vhost_scsi_destroy_vq_cmds(struct vhost_virtqueue *vq)
1439 {
1440         struct vhost_scsi_virtqueue *svq = container_of(vq,
1441                                         struct vhost_scsi_virtqueue, vq);
1442         struct vhost_scsi_cmd *tv_cmd;
1443         unsigned int i;
1444
1445         if (!svq->scsi_cmds)
1446                 return;
1447
1448         for (i = 0; i < svq->max_cmds; i++) {
1449                 tv_cmd = &svq->scsi_cmds[i];
1450
1451                 kfree(tv_cmd->tvc_sgl);
1452                 kfree(tv_cmd->tvc_prot_sgl);
1453                 kfree(tv_cmd->tvc_upages);
1454                 kfree(tv_cmd->tvc_resp_iov);
1455         }
1456
1457         sbitmap_free(&svq->scsi_tags);
1458         kfree(svq->scsi_cmds);
1459         svq->scsi_cmds = NULL;
1460 }
1461
1462 static int vhost_scsi_setup_vq_cmds(struct vhost_virtqueue *vq, int max_cmds)
1463 {
1464         struct vhost_scsi_virtqueue *svq = container_of(vq,
1465                                         struct vhost_scsi_virtqueue, vq);
1466         struct vhost_scsi_cmd *tv_cmd;
1467         unsigned int i;
1468
1469         if (svq->scsi_cmds)
1470                 return 0;
1471
1472         if (sbitmap_init_node(&svq->scsi_tags, max_cmds, -1, GFP_KERNEL,
1473                               NUMA_NO_NODE, false, true))
1474                 return -ENOMEM;
1475         svq->max_cmds = max_cmds;
1476
1477         svq->scsi_cmds = kcalloc(max_cmds, sizeof(*tv_cmd), GFP_KERNEL);
1478         if (!svq->scsi_cmds) {
1479                 sbitmap_free(&svq->scsi_tags);
1480                 return -ENOMEM;
1481         }
1482
1483         for (i = 0; i < max_cmds; i++) {
1484                 tv_cmd = &svq->scsi_cmds[i];
1485
1486                 tv_cmd->tvc_sgl = kcalloc(VHOST_SCSI_PREALLOC_SGLS,
1487                                           sizeof(struct scatterlist),
1488                                           GFP_KERNEL);
1489                 if (!tv_cmd->tvc_sgl) {
1490                         pr_err("Unable to allocate tv_cmd->tvc_sgl\n");
1491                         goto out;
1492                 }
1493
1494                 tv_cmd->tvc_upages = kcalloc(VHOST_SCSI_PREALLOC_UPAGES,
1495                                              sizeof(struct page *),
1496                                              GFP_KERNEL);
1497                 if (!tv_cmd->tvc_upages) {
1498                         pr_err("Unable to allocate tv_cmd->tvc_upages\n");
1499                         goto out;
1500                 }
1501
1502                 tv_cmd->tvc_resp_iov = kcalloc(UIO_MAXIOV,
1503                                                sizeof(struct iovec),
1504                                                GFP_KERNEL);
1505                 if (!tv_cmd->tvc_resp_iov) {
1506                         pr_err("Unable to allocate tv_cmd->tvc_resp_iov\n");
1507                         goto out;
1508                 }
1509
1510                 tv_cmd->tvc_prot_sgl = kcalloc(VHOST_SCSI_PREALLOC_PROT_SGLS,
1511                                                sizeof(struct scatterlist),
1512                                                GFP_KERNEL);
1513                 if (!tv_cmd->tvc_prot_sgl) {
1514                         pr_err("Unable to allocate tv_cmd->tvc_prot_sgl\n");
1515                         goto out;
1516                 }
1517         }
1518         return 0;
1519 out:
1520         vhost_scsi_destroy_vq_cmds(vq);
1521         return -ENOMEM;
1522 }
1523
1524 /*
1525  * Called from vhost_scsi_ioctl() context to walk the list of available
1526  * vhost_scsi_tpg with an active struct vhost_scsi_nexus
1527  *
1528  *  The lock nesting rule is:
1529  *    vhost_scsi_mutex -> vs->dev.mutex -> tpg->tv_tpg_mutex -> vq->mutex
1530  */
1531 static int
1532 vhost_scsi_set_endpoint(struct vhost_scsi *vs,
1533                         struct vhost_scsi_target *t)
1534 {
1535         struct se_portal_group *se_tpg;
1536         struct vhost_scsi_tport *tv_tport;
1537         struct vhost_scsi_tpg *tpg;
1538         struct vhost_scsi_tpg **vs_tpg;
1539         struct vhost_virtqueue *vq;
1540         int index, ret, i, len;
1541         bool match = false;
1542
1543         mutex_lock(&vhost_scsi_mutex);
1544         mutex_lock(&vs->dev.mutex);
1545
1546         /* Verify that ring has been setup correctly. */
1547         for (index = 0; index < vs->dev.nvqs; ++index) {
1548                 /* Verify that ring has been setup correctly. */
1549                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1550                         ret = -EFAULT;
1551                         goto out;
1552                 }
1553         }
1554
1555         len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET;
1556         vs_tpg = kzalloc(len, GFP_KERNEL);
1557         if (!vs_tpg) {
1558                 ret = -ENOMEM;
1559                 goto out;
1560         }
1561         if (vs->vs_tpg)
1562                 memcpy(vs_tpg, vs->vs_tpg, len);
1563
1564         list_for_each_entry(tpg, &vhost_scsi_list, tv_tpg_list) {
1565                 mutex_lock(&tpg->tv_tpg_mutex);
1566                 if (!tpg->tpg_nexus) {
1567                         mutex_unlock(&tpg->tv_tpg_mutex);
1568                         continue;
1569                 }
1570                 if (tpg->tv_tpg_vhost_count != 0) {
1571                         mutex_unlock(&tpg->tv_tpg_mutex);
1572                         continue;
1573                 }
1574                 tv_tport = tpg->tport;
1575
1576                 if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1577                         if (vs->vs_tpg && vs->vs_tpg[tpg->tport_tpgt]) {
1578                                 mutex_unlock(&tpg->tv_tpg_mutex);
1579                                 ret = -EEXIST;
1580                                 goto undepend;
1581                         }
1582                         /*
1583                          * In order to ensure individual vhost-scsi configfs
1584                          * groups cannot be removed while in use by vhost ioctl,
1585                          * go ahead and take an explicit se_tpg->tpg_group.cg_item
1586                          * dependency now.
1587                          */
1588                         se_tpg = &tpg->se_tpg;
1589                         ret = target_depend_item(&se_tpg->tpg_group.cg_item);
1590                         if (ret) {
1591                                 pr_warn("target_depend_item() failed: %d\n", ret);
1592                                 mutex_unlock(&tpg->tv_tpg_mutex);
1593                                 goto undepend;
1594                         }
1595                         tpg->tv_tpg_vhost_count++;
1596                         tpg->vhost_scsi = vs;
1597                         vs_tpg[tpg->tport_tpgt] = tpg;
1598                         match = true;
1599                 }
1600                 mutex_unlock(&tpg->tv_tpg_mutex);
1601         }
1602
1603         if (match) {
1604                 memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
1605                        sizeof(vs->vs_vhost_wwpn));
1606
1607                 for (i = VHOST_SCSI_VQ_IO; i < vs->dev.nvqs; i++) {
1608                         vq = &vs->vqs[i].vq;
1609                         if (!vhost_vq_is_setup(vq))
1610                                 continue;
1611
1612                         ret = vhost_scsi_setup_vq_cmds(vq, vq->num);
1613                         if (ret)
1614                                 goto destroy_vq_cmds;
1615                 }
1616
1617                 for (i = 0; i < vs->dev.nvqs; i++) {
1618                         vq = &vs->vqs[i].vq;
1619                         mutex_lock(&vq->mutex);
1620                         vhost_vq_set_backend(vq, vs_tpg);
1621                         vhost_vq_init_access(vq);
1622                         mutex_unlock(&vq->mutex);
1623                 }
1624                 ret = 0;
1625         } else {
1626                 ret = -EEXIST;
1627         }
1628
1629         /*
1630          * Act as synchronize_rcu to make sure access to
1631          * old vs->vs_tpg is finished.
1632          */
1633         vhost_scsi_flush(vs);
1634         kfree(vs->vs_tpg);
1635         vs->vs_tpg = vs_tpg;
1636         goto out;
1637
1638 destroy_vq_cmds:
1639         for (i--; i >= VHOST_SCSI_VQ_IO; i--) {
1640                 if (!vhost_vq_get_backend(&vs->vqs[i].vq))
1641                         vhost_scsi_destroy_vq_cmds(&vs->vqs[i].vq);
1642         }
1643 undepend:
1644         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1645                 tpg = vs_tpg[i];
1646                 if (tpg) {
1647                         mutex_lock(&tpg->tv_tpg_mutex);
1648                         tpg->vhost_scsi = NULL;
1649                         tpg->tv_tpg_vhost_count--;
1650                         mutex_unlock(&tpg->tv_tpg_mutex);
1651                         target_undepend_item(&tpg->se_tpg.tpg_group.cg_item);
1652                 }
1653         }
1654         kfree(vs_tpg);
1655 out:
1656         mutex_unlock(&vs->dev.mutex);
1657         mutex_unlock(&vhost_scsi_mutex);
1658         return ret;
1659 }
1660
1661 static int
1662 vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
1663                           struct vhost_scsi_target *t)
1664 {
1665         struct se_portal_group *se_tpg;
1666         struct vhost_scsi_tport *tv_tport;
1667         struct vhost_scsi_tpg *tpg;
1668         struct vhost_virtqueue *vq;
1669         bool match = false;
1670         int index, ret, i;
1671         u8 target;
1672
1673         mutex_lock(&vhost_scsi_mutex);
1674         mutex_lock(&vs->dev.mutex);
1675         /* Verify that ring has been setup correctly. */
1676         for (index = 0; index < vs->dev.nvqs; ++index) {
1677                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1678                         ret = -EFAULT;
1679                         goto err_dev;
1680                 }
1681         }
1682
1683         if (!vs->vs_tpg) {
1684                 ret = 0;
1685                 goto err_dev;
1686         }
1687
1688         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1689                 target = i;
1690                 tpg = vs->vs_tpg[target];
1691                 if (!tpg)
1692                         continue;
1693
1694                 tv_tport = tpg->tport;
1695                 if (!tv_tport) {
1696                         ret = -ENODEV;
1697                         goto err_dev;
1698                 }
1699
1700                 if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1701                         pr_warn("tv_tport->tport_name: %s, tpg->tport_tpgt: %hu"
1702                                 " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
1703                                 tv_tport->tport_name, tpg->tport_tpgt,
1704                                 t->vhost_wwpn, t->vhost_tpgt);
1705                         ret = -EINVAL;
1706                         goto err_dev;
1707                 }
1708                 match = true;
1709         }
1710         if (!match)
1711                 goto free_vs_tpg;
1712
1713         /* Prevent new cmds from starting and accessing the tpgs/sessions */
1714         for (i = 0; i < vs->dev.nvqs; i++) {
1715                 vq = &vs->vqs[i].vq;
1716                 mutex_lock(&vq->mutex);
1717                 vhost_vq_set_backend(vq, NULL);
1718                 mutex_unlock(&vq->mutex);
1719         }
1720         /* Make sure cmds are not running before tearing them down. */
1721         vhost_scsi_flush(vs);
1722
1723         for (i = 0; i < vs->dev.nvqs; i++) {
1724                 vq = &vs->vqs[i].vq;
1725                 vhost_scsi_destroy_vq_cmds(vq);
1726         }
1727
1728         /*
1729          * We can now release our hold on the tpg and sessions and userspace
1730          * can free them after this point.
1731          */
1732         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1733                 target = i;
1734                 tpg = vs->vs_tpg[target];
1735                 if (!tpg)
1736                         continue;
1737
1738                 mutex_lock(&tpg->tv_tpg_mutex);
1739
1740                 tpg->tv_tpg_vhost_count--;
1741                 tpg->vhost_scsi = NULL;
1742                 vs->vs_tpg[target] = NULL;
1743
1744                 mutex_unlock(&tpg->tv_tpg_mutex);
1745
1746                 se_tpg = &tpg->se_tpg;
1747                 target_undepend_item(&se_tpg->tpg_group.cg_item);
1748         }
1749
1750 free_vs_tpg:
1751         /*
1752          * Act as synchronize_rcu to make sure access to
1753          * old vs->vs_tpg is finished.
1754          */
1755         vhost_scsi_flush(vs);
1756         kfree(vs->vs_tpg);
1757         vs->vs_tpg = NULL;
1758         WARN_ON(vs->vs_events_nr);
1759         mutex_unlock(&vs->dev.mutex);
1760         mutex_unlock(&vhost_scsi_mutex);
1761         return 0;
1762
1763 err_dev:
1764         mutex_unlock(&vs->dev.mutex);
1765         mutex_unlock(&vhost_scsi_mutex);
1766         return ret;
1767 }
1768
1769 static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features)
1770 {
1771         struct vhost_virtqueue *vq;
1772         int i;
1773
1774         if (features & ~VHOST_SCSI_FEATURES)
1775                 return -EOPNOTSUPP;
1776
1777         mutex_lock(&vs->dev.mutex);
1778         if ((features & (1 << VHOST_F_LOG_ALL)) &&
1779             !vhost_log_access_ok(&vs->dev)) {
1780                 mutex_unlock(&vs->dev.mutex);
1781                 return -EFAULT;
1782         }
1783
1784         for (i = 0; i < vs->dev.nvqs; i++) {
1785                 vq = &vs->vqs[i].vq;
1786                 mutex_lock(&vq->mutex);
1787                 vq->acked_features = features;
1788                 mutex_unlock(&vq->mutex);
1789         }
1790         mutex_unlock(&vs->dev.mutex);
1791         return 0;
1792 }
1793
1794 static int vhost_scsi_open(struct inode *inode, struct file *f)
1795 {
1796         struct vhost_scsi *vs;
1797         struct vhost_virtqueue **vqs;
1798         int r = -ENOMEM, i, nvqs = vhost_scsi_max_io_vqs;
1799
1800         vs = kvzalloc(sizeof(*vs), GFP_KERNEL);
1801         if (!vs)
1802                 goto err_vs;
1803
1804         if (nvqs > VHOST_SCSI_MAX_IO_VQ) {
1805                 pr_err("Invalid max_io_vqs of %d. Using %d.\n", nvqs,
1806                        VHOST_SCSI_MAX_IO_VQ);
1807                 nvqs = VHOST_SCSI_MAX_IO_VQ;
1808         } else if (nvqs == 0) {
1809                 pr_err("Invalid max_io_vqs of %d. Using 1.\n", nvqs);
1810                 nvqs = 1;
1811         }
1812         nvqs += VHOST_SCSI_VQ_IO;
1813
1814         vs->compl_bitmap = bitmap_alloc(nvqs, GFP_KERNEL);
1815         if (!vs->compl_bitmap)
1816                 goto err_compl_bitmap;
1817
1818         vs->old_inflight = kmalloc_array(nvqs, sizeof(*vs->old_inflight),
1819                                          GFP_KERNEL | __GFP_ZERO);
1820         if (!vs->old_inflight)
1821                 goto err_inflight;
1822
1823         vs->vqs = kmalloc_array(nvqs, sizeof(*vs->vqs),
1824                                 GFP_KERNEL | __GFP_ZERO);
1825         if (!vs->vqs)
1826                 goto err_vqs;
1827
1828         vqs = kmalloc_array(nvqs, sizeof(*vqs), GFP_KERNEL);
1829         if (!vqs)
1830                 goto err_local_vqs;
1831
1832         vhost_work_init(&vs->vs_completion_work, vhost_scsi_complete_cmd_work);
1833         vhost_work_init(&vs->vs_event_work, vhost_scsi_evt_work);
1834
1835         vs->vs_events_nr = 0;
1836         vs->vs_events_missed = false;
1837
1838         vqs[VHOST_SCSI_VQ_CTL] = &vs->vqs[VHOST_SCSI_VQ_CTL].vq;
1839         vqs[VHOST_SCSI_VQ_EVT] = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1840         vs->vqs[VHOST_SCSI_VQ_CTL].vq.handle_kick = vhost_scsi_ctl_handle_kick;
1841         vs->vqs[VHOST_SCSI_VQ_EVT].vq.handle_kick = vhost_scsi_evt_handle_kick;
1842         for (i = VHOST_SCSI_VQ_IO; i < nvqs; i++) {
1843                 vqs[i] = &vs->vqs[i].vq;
1844                 vs->vqs[i].vq.handle_kick = vhost_scsi_handle_kick;
1845         }
1846         vhost_dev_init(&vs->dev, vqs, nvqs, UIO_MAXIOV,
1847                        VHOST_SCSI_WEIGHT, 0, true, NULL);
1848
1849         vhost_scsi_init_inflight(vs, NULL);
1850
1851         f->private_data = vs;
1852         return 0;
1853
1854 err_local_vqs:
1855         kfree(vs->vqs);
1856 err_vqs:
1857         kfree(vs->old_inflight);
1858 err_inflight:
1859         bitmap_free(vs->compl_bitmap);
1860 err_compl_bitmap:
1861         kvfree(vs);
1862 err_vs:
1863         return r;
1864 }
1865
1866 static int vhost_scsi_release(struct inode *inode, struct file *f)
1867 {
1868         struct vhost_scsi *vs = f->private_data;
1869         struct vhost_scsi_target t;
1870
1871         mutex_lock(&vs->dev.mutex);
1872         memcpy(t.vhost_wwpn, vs->vs_vhost_wwpn, sizeof(t.vhost_wwpn));
1873         mutex_unlock(&vs->dev.mutex);
1874         vhost_scsi_clear_endpoint(vs, &t);
1875         vhost_dev_stop(&vs->dev);
1876         vhost_dev_cleanup(&vs->dev);
1877         kfree(vs->dev.vqs);
1878         kfree(vs->vqs);
1879         kfree(vs->old_inflight);
1880         bitmap_free(vs->compl_bitmap);
1881         kvfree(vs);
1882         return 0;
1883 }
1884
1885 static long
1886 vhost_scsi_ioctl(struct file *f,
1887                  unsigned int ioctl,
1888                  unsigned long arg)
1889 {
1890         struct vhost_scsi *vs = f->private_data;
1891         struct vhost_scsi_target backend;
1892         void __user *argp = (void __user *)arg;
1893         u64 __user *featurep = argp;
1894         u32 __user *eventsp = argp;
1895         u32 events_missed;
1896         u64 features;
1897         int r, abi_version = VHOST_SCSI_ABI_VERSION;
1898         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1899
1900         switch (ioctl) {
1901         case VHOST_SCSI_SET_ENDPOINT:
1902                 if (copy_from_user(&backend, argp, sizeof backend))
1903                         return -EFAULT;
1904                 if (backend.reserved != 0)
1905                         return -EOPNOTSUPP;
1906
1907                 return vhost_scsi_set_endpoint(vs, &backend);
1908         case VHOST_SCSI_CLEAR_ENDPOINT:
1909                 if (copy_from_user(&backend, argp, sizeof backend))
1910                         return -EFAULT;
1911                 if (backend.reserved != 0)
1912                         return -EOPNOTSUPP;
1913
1914                 return vhost_scsi_clear_endpoint(vs, &backend);
1915         case VHOST_SCSI_GET_ABI_VERSION:
1916                 if (copy_to_user(argp, &abi_version, sizeof abi_version))
1917                         return -EFAULT;
1918                 return 0;
1919         case VHOST_SCSI_SET_EVENTS_MISSED:
1920                 if (get_user(events_missed, eventsp))
1921                         return -EFAULT;
1922                 mutex_lock(&vq->mutex);
1923                 vs->vs_events_missed = events_missed;
1924                 mutex_unlock(&vq->mutex);
1925                 return 0;
1926         case VHOST_SCSI_GET_EVENTS_MISSED:
1927                 mutex_lock(&vq->mutex);
1928                 events_missed = vs->vs_events_missed;
1929                 mutex_unlock(&vq->mutex);
1930                 if (put_user(events_missed, eventsp))
1931                         return -EFAULT;
1932                 return 0;
1933         case VHOST_GET_FEATURES:
1934                 features = VHOST_SCSI_FEATURES;
1935                 if (copy_to_user(featurep, &features, sizeof features))
1936                         return -EFAULT;
1937                 return 0;
1938         case VHOST_SET_FEATURES:
1939                 if (copy_from_user(&features, featurep, sizeof features))
1940                         return -EFAULT;
1941                 return vhost_scsi_set_features(vs, features);
1942         default:
1943                 mutex_lock(&vs->dev.mutex);
1944                 r = vhost_dev_ioctl(&vs->dev, ioctl, argp);
1945                 /* TODO: flush backend after dev ioctl. */
1946                 if (r == -ENOIOCTLCMD)
1947                         r = vhost_vring_ioctl(&vs->dev, ioctl, argp);
1948                 mutex_unlock(&vs->dev.mutex);
1949                 return r;
1950         }
1951 }
1952
1953 static const struct file_operations vhost_scsi_fops = {
1954         .owner          = THIS_MODULE,
1955         .release        = vhost_scsi_release,
1956         .unlocked_ioctl = vhost_scsi_ioctl,
1957         .compat_ioctl   = compat_ptr_ioctl,
1958         .open           = vhost_scsi_open,
1959         .llseek         = noop_llseek,
1960 };
1961
1962 static struct miscdevice vhost_scsi_misc = {
1963         MISC_DYNAMIC_MINOR,
1964         "vhost-scsi",
1965         &vhost_scsi_fops,
1966 };
1967
1968 static int __init vhost_scsi_register(void)
1969 {
1970         return misc_register(&vhost_scsi_misc);
1971 }
1972
1973 static void vhost_scsi_deregister(void)
1974 {
1975         misc_deregister(&vhost_scsi_misc);
1976 }
1977
1978 static char *vhost_scsi_dump_proto_id(struct vhost_scsi_tport *tport)
1979 {
1980         switch (tport->tport_proto_id) {
1981         case SCSI_PROTOCOL_SAS:
1982                 return "SAS";
1983         case SCSI_PROTOCOL_FCP:
1984                 return "FCP";
1985         case SCSI_PROTOCOL_ISCSI:
1986                 return "iSCSI";
1987         default:
1988                 break;
1989         }
1990
1991         return "Unknown";
1992 }
1993
1994 static void
1995 vhost_scsi_do_plug(struct vhost_scsi_tpg *tpg,
1996                   struct se_lun *lun, bool plug)
1997 {
1998
1999         struct vhost_scsi *vs = tpg->vhost_scsi;
2000         struct vhost_virtqueue *vq;
2001         u32 reason;
2002
2003         if (!vs)
2004                 return;
2005
2006         if (plug)
2007                 reason = VIRTIO_SCSI_EVT_RESET_RESCAN;
2008         else
2009                 reason = VIRTIO_SCSI_EVT_RESET_REMOVED;
2010
2011         vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
2012         mutex_lock(&vq->mutex);
2013         /*
2014          * We can't queue events if the backend has been cleared, because
2015          * we could end up queueing an event after the flush.
2016          */
2017         if (!vhost_vq_get_backend(vq))
2018                 goto unlock;
2019
2020         if (vhost_has_feature(vq, VIRTIO_SCSI_F_HOTPLUG))
2021                 vhost_scsi_send_evt(vs, tpg, lun,
2022                                    VIRTIO_SCSI_T_TRANSPORT_RESET, reason);
2023 unlock:
2024         mutex_unlock(&vq->mutex);
2025 }
2026
2027 static void vhost_scsi_hotplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
2028 {
2029         vhost_scsi_do_plug(tpg, lun, true);
2030 }
2031
2032 static void vhost_scsi_hotunplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
2033 {
2034         vhost_scsi_do_plug(tpg, lun, false);
2035 }
2036
2037 static int vhost_scsi_port_link(struct se_portal_group *se_tpg,
2038                                struct se_lun *lun)
2039 {
2040         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2041                                 struct vhost_scsi_tpg, se_tpg);
2042
2043         mutex_lock(&tpg->tv_tpg_mutex);
2044         tpg->tv_tpg_port_count++;
2045         vhost_scsi_hotplug(tpg, lun);
2046         mutex_unlock(&tpg->tv_tpg_mutex);
2047
2048         return 0;
2049 }
2050
2051 static void vhost_scsi_port_unlink(struct se_portal_group *se_tpg,
2052                                   struct se_lun *lun)
2053 {
2054         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2055                                 struct vhost_scsi_tpg, se_tpg);
2056
2057         mutex_lock(&tpg->tv_tpg_mutex);
2058         tpg->tv_tpg_port_count--;
2059         vhost_scsi_hotunplug(tpg, lun);
2060         mutex_unlock(&tpg->tv_tpg_mutex);
2061 }
2062
2063 static ssize_t vhost_scsi_tpg_attrib_fabric_prot_type_store(
2064                 struct config_item *item, const char *page, size_t count)
2065 {
2066         struct se_portal_group *se_tpg = attrib_to_tpg(item);
2067         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2068                                 struct vhost_scsi_tpg, se_tpg);
2069         unsigned long val;
2070         int ret = kstrtoul(page, 0, &val);
2071
2072         if (ret) {
2073                 pr_err("kstrtoul() returned %d for fabric_prot_type\n", ret);
2074                 return ret;
2075         }
2076         if (val != 0 && val != 1 && val != 3) {
2077                 pr_err("Invalid vhost_scsi fabric_prot_type: %lu\n", val);
2078                 return -EINVAL;
2079         }
2080         tpg->tv_fabric_prot_type = val;
2081
2082         return count;
2083 }
2084
2085 static ssize_t vhost_scsi_tpg_attrib_fabric_prot_type_show(
2086                 struct config_item *item, char *page)
2087 {
2088         struct se_portal_group *se_tpg = attrib_to_tpg(item);
2089         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2090                                 struct vhost_scsi_tpg, se_tpg);
2091
2092         return sysfs_emit(page, "%d\n", tpg->tv_fabric_prot_type);
2093 }
2094
2095 CONFIGFS_ATTR(vhost_scsi_tpg_attrib_, fabric_prot_type);
2096
2097 static struct configfs_attribute *vhost_scsi_tpg_attrib_attrs[] = {
2098         &vhost_scsi_tpg_attrib_attr_fabric_prot_type,
2099         NULL,
2100 };
2101
2102 static int vhost_scsi_make_nexus(struct vhost_scsi_tpg *tpg,
2103                                 const char *name)
2104 {
2105         struct vhost_scsi_nexus *tv_nexus;
2106
2107         mutex_lock(&tpg->tv_tpg_mutex);
2108         if (tpg->tpg_nexus) {
2109                 mutex_unlock(&tpg->tv_tpg_mutex);
2110                 pr_debug("tpg->tpg_nexus already exists\n");
2111                 return -EEXIST;
2112         }
2113
2114         tv_nexus = kzalloc(sizeof(*tv_nexus), GFP_KERNEL);
2115         if (!tv_nexus) {
2116                 mutex_unlock(&tpg->tv_tpg_mutex);
2117                 pr_err("Unable to allocate struct vhost_scsi_nexus\n");
2118                 return -ENOMEM;
2119         }
2120         /*
2121          * Since we are running in 'demo mode' this call with generate a
2122          * struct se_node_acl for the vhost_scsi struct se_portal_group with
2123          * the SCSI Initiator port name of the passed configfs group 'name'.
2124          */
2125         tv_nexus->tvn_se_sess = target_setup_session(&tpg->se_tpg, 0, 0,
2126                                         TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS,
2127                                         (unsigned char *)name, tv_nexus, NULL);
2128         if (IS_ERR(tv_nexus->tvn_se_sess)) {
2129                 mutex_unlock(&tpg->tv_tpg_mutex);
2130                 kfree(tv_nexus);
2131                 return -ENOMEM;
2132         }
2133         tpg->tpg_nexus = tv_nexus;
2134
2135         mutex_unlock(&tpg->tv_tpg_mutex);
2136         return 0;
2137 }
2138
2139 static int vhost_scsi_drop_nexus(struct vhost_scsi_tpg *tpg)
2140 {
2141         struct se_session *se_sess;
2142         struct vhost_scsi_nexus *tv_nexus;
2143
2144         mutex_lock(&tpg->tv_tpg_mutex);
2145         tv_nexus = tpg->tpg_nexus;
2146         if (!tv_nexus) {
2147                 mutex_unlock(&tpg->tv_tpg_mutex);
2148                 return -ENODEV;
2149         }
2150
2151         se_sess = tv_nexus->tvn_se_sess;
2152         if (!se_sess) {
2153                 mutex_unlock(&tpg->tv_tpg_mutex);
2154                 return -ENODEV;
2155         }
2156
2157         if (tpg->tv_tpg_port_count != 0) {
2158                 mutex_unlock(&tpg->tv_tpg_mutex);
2159                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
2160                         " active TPG port count: %d\n",
2161                         tpg->tv_tpg_port_count);
2162                 return -EBUSY;
2163         }
2164
2165         if (tpg->tv_tpg_vhost_count != 0) {
2166                 mutex_unlock(&tpg->tv_tpg_mutex);
2167                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
2168                         " active TPG vhost count: %d\n",
2169                         tpg->tv_tpg_vhost_count);
2170                 return -EBUSY;
2171         }
2172
2173         pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated"
2174                 " %s Initiator Port: %s\n", vhost_scsi_dump_proto_id(tpg->tport),
2175                 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
2176
2177         /*
2178          * Release the SCSI I_T Nexus to the emulated vhost Target Port
2179          */
2180         target_remove_session(se_sess);
2181         tpg->tpg_nexus = NULL;
2182         mutex_unlock(&tpg->tv_tpg_mutex);
2183
2184         kfree(tv_nexus);
2185         return 0;
2186 }
2187
2188 static ssize_t vhost_scsi_tpg_nexus_show(struct config_item *item, char *page)
2189 {
2190         struct se_portal_group *se_tpg = to_tpg(item);
2191         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2192                                 struct vhost_scsi_tpg, se_tpg);
2193         struct vhost_scsi_nexus *tv_nexus;
2194         ssize_t ret;
2195
2196         mutex_lock(&tpg->tv_tpg_mutex);
2197         tv_nexus = tpg->tpg_nexus;
2198         if (!tv_nexus) {
2199                 mutex_unlock(&tpg->tv_tpg_mutex);
2200                 return -ENODEV;
2201         }
2202         ret = sysfs_emit(page, "%s\n",
2203                         tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
2204         mutex_unlock(&tpg->tv_tpg_mutex);
2205
2206         return ret;
2207 }
2208
2209 static ssize_t vhost_scsi_tpg_nexus_store(struct config_item *item,
2210                 const char *page, size_t count)
2211 {
2212         struct se_portal_group *se_tpg = to_tpg(item);
2213         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2214                                 struct vhost_scsi_tpg, se_tpg);
2215         struct vhost_scsi_tport *tport_wwn = tpg->tport;
2216         unsigned char i_port[VHOST_SCSI_NAMELEN], *ptr, *port_ptr;
2217         int ret;
2218         /*
2219          * Shutdown the active I_T nexus if 'NULL' is passed..
2220          */
2221         if (!strncmp(page, "NULL", 4)) {
2222                 ret = vhost_scsi_drop_nexus(tpg);
2223                 return (!ret) ? count : ret;
2224         }
2225         /*
2226          * Otherwise make sure the passed virtual Initiator port WWN matches
2227          * the fabric protocol_id set in vhost_scsi_make_tport(), and call
2228          * vhost_scsi_make_nexus().
2229          */
2230         if (strlen(page) >= VHOST_SCSI_NAMELEN) {
2231                 pr_err("Emulated NAA Sas Address: %s, exceeds"
2232                                 " max: %d\n", page, VHOST_SCSI_NAMELEN);
2233                 return -EINVAL;
2234         }
2235         snprintf(&i_port[0], VHOST_SCSI_NAMELEN, "%s", page);
2236
2237         ptr = strstr(i_port, "naa.");
2238         if (ptr) {
2239                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
2240                         pr_err("Passed SAS Initiator Port %s does not"
2241                                 " match target port protoid: %s\n", i_port,
2242                                 vhost_scsi_dump_proto_id(tport_wwn));
2243                         return -EINVAL;
2244                 }
2245                 port_ptr = &i_port[0];
2246                 goto check_newline;
2247         }
2248         ptr = strstr(i_port, "fc.");
2249         if (ptr) {
2250                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
2251                         pr_err("Passed FCP Initiator Port %s does not"
2252                                 " match target port protoid: %s\n", i_port,
2253                                 vhost_scsi_dump_proto_id(tport_wwn));
2254                         return -EINVAL;
2255                 }
2256                 port_ptr = &i_port[3]; /* Skip over "fc." */
2257                 goto check_newline;
2258         }
2259         ptr = strstr(i_port, "iqn.");
2260         if (ptr) {
2261                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
2262                         pr_err("Passed iSCSI Initiator Port %s does not"
2263                                 " match target port protoid: %s\n", i_port,
2264                                 vhost_scsi_dump_proto_id(tport_wwn));
2265                         return -EINVAL;
2266                 }
2267                 port_ptr = &i_port[0];
2268                 goto check_newline;
2269         }
2270         pr_err("Unable to locate prefix for emulated Initiator Port:"
2271                         " %s\n", i_port);
2272         return -EINVAL;
2273         /*
2274          * Clear any trailing newline for the NAA WWN
2275          */
2276 check_newline:
2277         if (i_port[strlen(i_port)-1] == '\n')
2278                 i_port[strlen(i_port)-1] = '\0';
2279
2280         ret = vhost_scsi_make_nexus(tpg, port_ptr);
2281         if (ret < 0)
2282                 return ret;
2283
2284         return count;
2285 }
2286
2287 CONFIGFS_ATTR(vhost_scsi_tpg_, nexus);
2288
2289 static struct configfs_attribute *vhost_scsi_tpg_attrs[] = {
2290         &vhost_scsi_tpg_attr_nexus,
2291         NULL,
2292 };
2293
2294 static struct se_portal_group *
2295 vhost_scsi_make_tpg(struct se_wwn *wwn, const char *name)
2296 {
2297         struct vhost_scsi_tport *tport = container_of(wwn,
2298                         struct vhost_scsi_tport, tport_wwn);
2299
2300         struct vhost_scsi_tpg *tpg;
2301         u16 tpgt;
2302         int ret;
2303
2304         if (strstr(name, "tpgt_") != name)
2305                 return ERR_PTR(-EINVAL);
2306         if (kstrtou16(name + 5, 10, &tpgt) || tpgt >= VHOST_SCSI_MAX_TARGET)
2307                 return ERR_PTR(-EINVAL);
2308
2309         tpg = kzalloc(sizeof(*tpg), GFP_KERNEL);
2310         if (!tpg) {
2311                 pr_err("Unable to allocate struct vhost_scsi_tpg");
2312                 return ERR_PTR(-ENOMEM);
2313         }
2314         mutex_init(&tpg->tv_tpg_mutex);
2315         INIT_LIST_HEAD(&tpg->tv_tpg_list);
2316         tpg->tport = tport;
2317         tpg->tport_tpgt = tpgt;
2318
2319         ret = core_tpg_register(wwn, &tpg->se_tpg, tport->tport_proto_id);
2320         if (ret < 0) {
2321                 kfree(tpg);
2322                 return NULL;
2323         }
2324         mutex_lock(&vhost_scsi_mutex);
2325         list_add_tail(&tpg->tv_tpg_list, &vhost_scsi_list);
2326         mutex_unlock(&vhost_scsi_mutex);
2327
2328         return &tpg->se_tpg;
2329 }
2330
2331 static void vhost_scsi_drop_tpg(struct se_portal_group *se_tpg)
2332 {
2333         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2334                                 struct vhost_scsi_tpg, se_tpg);
2335
2336         mutex_lock(&vhost_scsi_mutex);
2337         list_del(&tpg->tv_tpg_list);
2338         mutex_unlock(&vhost_scsi_mutex);
2339         /*
2340          * Release the virtual I_T Nexus for this vhost TPG
2341          */
2342         vhost_scsi_drop_nexus(tpg);
2343         /*
2344          * Deregister the se_tpg from TCM..
2345          */
2346         core_tpg_deregister(se_tpg);
2347         kfree(tpg);
2348 }
2349
2350 static struct se_wwn *
2351 vhost_scsi_make_tport(struct target_fabric_configfs *tf,
2352                      struct config_group *group,
2353                      const char *name)
2354 {
2355         struct vhost_scsi_tport *tport;
2356         char *ptr;
2357         u64 wwpn = 0;
2358         int off = 0;
2359
2360         /* if (vhost_scsi_parse_wwn(name, &wwpn, 1) < 0)
2361                 return ERR_PTR(-EINVAL); */
2362
2363         tport = kzalloc(sizeof(*tport), GFP_KERNEL);
2364         if (!tport) {
2365                 pr_err("Unable to allocate struct vhost_scsi_tport");
2366                 return ERR_PTR(-ENOMEM);
2367         }
2368         tport->tport_wwpn = wwpn;
2369         /*
2370          * Determine the emulated Protocol Identifier and Target Port Name
2371          * based on the incoming configfs directory name.
2372          */
2373         ptr = strstr(name, "naa.");
2374         if (ptr) {
2375                 tport->tport_proto_id = SCSI_PROTOCOL_SAS;
2376                 goto check_len;
2377         }
2378         ptr = strstr(name, "fc.");
2379         if (ptr) {
2380                 tport->tport_proto_id = SCSI_PROTOCOL_FCP;
2381                 off = 3; /* Skip over "fc." */
2382                 goto check_len;
2383         }
2384         ptr = strstr(name, "iqn.");
2385         if (ptr) {
2386                 tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
2387                 goto check_len;
2388         }
2389
2390         pr_err("Unable to locate prefix for emulated Target Port:"
2391                         " %s\n", name);
2392         kfree(tport);
2393         return ERR_PTR(-EINVAL);
2394
2395 check_len:
2396         if (strlen(name) >= VHOST_SCSI_NAMELEN) {
2397                 pr_err("Emulated %s Address: %s, exceeds"
2398                         " max: %d\n", name, vhost_scsi_dump_proto_id(tport),
2399                         VHOST_SCSI_NAMELEN);
2400                 kfree(tport);
2401                 return ERR_PTR(-EINVAL);
2402         }
2403         snprintf(&tport->tport_name[0], VHOST_SCSI_NAMELEN, "%s", &name[off]);
2404
2405         pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target"
2406                 " %s Address: %s\n", vhost_scsi_dump_proto_id(tport), name);
2407
2408         return &tport->tport_wwn;
2409 }
2410
2411 static void vhost_scsi_drop_tport(struct se_wwn *wwn)
2412 {
2413         struct vhost_scsi_tport *tport = container_of(wwn,
2414                                 struct vhost_scsi_tport, tport_wwn);
2415
2416         pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target"
2417                 " %s Address: %s\n", vhost_scsi_dump_proto_id(tport),
2418                 tport->tport_name);
2419
2420         kfree(tport);
2421 }
2422
2423 static ssize_t
2424 vhost_scsi_wwn_version_show(struct config_item *item, char *page)
2425 {
2426         return sysfs_emit(page, "TCM_VHOST fabric module %s on %s/%s"
2427                 "on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
2428                 utsname()->machine);
2429 }
2430
2431 CONFIGFS_ATTR_RO(vhost_scsi_wwn_, version);
2432
2433 static struct configfs_attribute *vhost_scsi_wwn_attrs[] = {
2434         &vhost_scsi_wwn_attr_version,
2435         NULL,
2436 };
2437
2438 static const struct target_core_fabric_ops vhost_scsi_ops = {
2439         .module                         = THIS_MODULE,
2440         .fabric_name                    = "vhost",
2441         .max_data_sg_nents              = VHOST_SCSI_PREALLOC_SGLS,
2442         .tpg_get_wwn                    = vhost_scsi_get_fabric_wwn,
2443         .tpg_get_tag                    = vhost_scsi_get_tpgt,
2444         .tpg_check_demo_mode            = vhost_scsi_check_true,
2445         .tpg_check_demo_mode_cache      = vhost_scsi_check_true,
2446         .tpg_check_demo_mode_write_protect = vhost_scsi_check_false,
2447         .tpg_check_prod_mode_write_protect = vhost_scsi_check_false,
2448         .tpg_check_prot_fabric_only     = vhost_scsi_check_prot_fabric_only,
2449         .tpg_get_inst_index             = vhost_scsi_tpg_get_inst_index,
2450         .release_cmd                    = vhost_scsi_release_cmd,
2451         .check_stop_free                = vhost_scsi_check_stop_free,
2452         .sess_get_index                 = vhost_scsi_sess_get_index,
2453         .sess_get_initiator_sid         = NULL,
2454         .write_pending                  = vhost_scsi_write_pending,
2455         .set_default_node_attributes    = vhost_scsi_set_default_node_attrs,
2456         .get_cmd_state                  = vhost_scsi_get_cmd_state,
2457         .queue_data_in                  = vhost_scsi_queue_data_in,
2458         .queue_status                   = vhost_scsi_queue_status,
2459         .queue_tm_rsp                   = vhost_scsi_queue_tm_rsp,
2460         .aborted_task                   = vhost_scsi_aborted_task,
2461         /*
2462          * Setup callers for generic logic in target_core_fabric_configfs.c
2463          */
2464         .fabric_make_wwn                = vhost_scsi_make_tport,
2465         .fabric_drop_wwn                = vhost_scsi_drop_tport,
2466         .fabric_make_tpg                = vhost_scsi_make_tpg,
2467         .fabric_drop_tpg                = vhost_scsi_drop_tpg,
2468         .fabric_post_link               = vhost_scsi_port_link,
2469         .fabric_pre_unlink              = vhost_scsi_port_unlink,
2470
2471         .tfc_wwn_attrs                  = vhost_scsi_wwn_attrs,
2472         .tfc_tpg_base_attrs             = vhost_scsi_tpg_attrs,
2473         .tfc_tpg_attrib_attrs           = vhost_scsi_tpg_attrib_attrs,
2474 };
2475
2476 static int __init vhost_scsi_init(void)
2477 {
2478         int ret = -ENOMEM;
2479
2480         pr_debug("TCM_VHOST fabric module %s on %s/%s"
2481                 " on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
2482                 utsname()->machine);
2483
2484         ret = vhost_scsi_register();
2485         if (ret < 0)
2486                 goto out;
2487
2488         ret = target_register_template(&vhost_scsi_ops);
2489         if (ret < 0)
2490                 goto out_vhost_scsi_deregister;
2491
2492         return 0;
2493
2494 out_vhost_scsi_deregister:
2495         vhost_scsi_deregister();
2496 out:
2497         return ret;
2498 };
2499
2500 static void vhost_scsi_exit(void)
2501 {
2502         target_unregister_template(&vhost_scsi_ops);
2503         vhost_scsi_deregister();
2504 };
2505
2506 MODULE_DESCRIPTION("VHOST_SCSI series fabric driver");
2507 MODULE_ALIAS("tcm_vhost");
2508 MODULE_LICENSE("GPL");
2509 module_init(vhost_scsi_init);
2510 module_exit(vhost_scsi_exit);