drivers/vhost/scsi.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*******************************************************************************
   3  * Vhost kernel TCM fabric driver for virtio SCSI initiators
   4  *
   5  * (C) Copyright 2010-2013 Datera, Inc.
   6  * (C) Copyright 2010-2012 IBM Corp.
   7  *
   8  * Authors: Nicholas A. Bellinger <nab@daterainc.com>
   9  *          Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
  10  ****************************************************************************/
  11
  12 #include <linux/module.h>
  13 #include <linux/moduleparam.h>
  14 #include <generated/utsrelease.h>
  15 #include <linux/utsname.h>
  16 #include <linux/init.h>
  17 #include <linux/slab.h>
  18 #include <linux/kthread.h>
  19 #include <linux/types.h>
  20 #include <linux/string.h>
  21 #include <linux/configfs.h>
  22 #include <linux/ctype.h>
  23 #include <linux/compat.h>
  24 #include <linux/eventfd.h>
  25 #include <linux/fs.h>
  26 #include <linux/vmalloc.h>
  27 #include <linux/miscdevice.h>
  28 #include <asm/unaligned.h>
  29 #include <scsi/scsi_common.h>
  30 #include <scsi/scsi_proto.h>
  31 #include <target/target_core_base.h>
  32 #include <target/target_core_fabric.h>
  33 #include <linux/vhost.h>
  34 #include <linux/virtio_scsi.h>
  35 #include <linux/llist.h>
  36 #include <linux/bitmap.h>
  37
  38 #include "vhost.h"
  39
  40 #define VHOST_SCSI_VERSION  "v0.1"
  41 #define VHOST_SCSI_NAMELEN 256
  42 #define VHOST_SCSI_MAX_CDB_SIZE 32
  43 #define VHOST_SCSI_PREALLOC_SGLS 2048
  44 #define VHOST_SCSI_PREALLOC_UPAGES 2048
  45 #define VHOST_SCSI_PREALLOC_PROT_SGLS 2048
  46
  47 /* Max number of requests before requeueing the job.
  48  * Using this limit prevents one virtqueue from starving others with
  49  * request.
  50  */
  51 #define VHOST_SCSI_WEIGHT 256
  52
  53 struct vhost_scsi_inflight {
  54         /* Wait for the flush operation to finish */
  55         struct completion comp;
  56         /* Refcount for the inflight reqs */
  57         struct kref kref;
  58 };
  59
  60 struct vhost_scsi_cmd {
  61         /* Descriptor from vhost_get_vq_desc() for virt_queue segment */
  62         int tvc_vq_desc;
  63         /* virtio-scsi initiator task attribute */
  64         int tvc_task_attr;
  65         /* virtio-scsi response incoming iovecs */
  66         int tvc_in_iovs;
  67         /* virtio-scsi initiator data direction */
  68         enum dma_data_direction tvc_data_direction;
  69         /* Expected data transfer length from virtio-scsi header */
  70         u32 tvc_exp_data_len;
  71         /* The Tag from include/linux/virtio_scsi.h:struct virtio_scsi_cmd_req */
  72         u64 tvc_tag;
  73         /* The number of scatterlists associated with this cmd */
  74         u32 tvc_sgl_count;
  75         u32 tvc_prot_sgl_count;
  76         /* Saved unpacked SCSI LUN for vhost_scsi_target_queue_cmd() */
  77         u32 tvc_lun;
  78         /* Pointer to the SGL formatted memory from virtio-scsi */
  79         struct scatterlist *tvc_sgl;
  80         struct scatterlist *tvc_prot_sgl;
  81         struct page **tvc_upages;
  82         /* Pointer to response header iovec */
  83         struct iovec tvc_resp_iov;
  84         /* Pointer to vhost_scsi for our device */
  85         struct vhost_scsi *tvc_vhost;
  86         /* Pointer to vhost_virtqueue for the cmd */
  87         struct vhost_virtqueue *tvc_vq;
  88         /* Pointer to vhost nexus memory */
  89         struct vhost_scsi_nexus *tvc_nexus;
  90         /* The TCM I/O descriptor that is accessed via container_of() */
  91         struct se_cmd tvc_se_cmd;
  92         /* Copy of the incoming SCSI command descriptor block (CDB) */
  93         unsigned char tvc_cdb[VHOST_SCSI_MAX_CDB_SIZE];
  94         /* Sense buffer that will be mapped into outgoing status */
  95         unsigned char tvc_sense_buf[TRANSPORT_SENSE_BUFFER];
  96         /* Completed commands list, serviced from vhost worker thread */
  97         struct llist_node tvc_completion_list;
  98         /* Used to track inflight cmd */
  99         struct vhost_scsi_inflight *inflight;
 100 };
 101
 102 struct vhost_scsi_nexus {
 103         /* Pointer to TCM session for I_T Nexus */
 104         struct se_session *tvn_se_sess;
 105 };
 106
 107 struct vhost_scsi_tpg {
 108         /* Vhost port target portal group tag for TCM */
 109         u16 tport_tpgt;
 110         /* Used to track number of TPG Port/Lun Links wrt to explict I_T Nexus shutdown */
 111         int tv_tpg_port_count;
 112         /* Used for vhost_scsi device reference to tpg_nexus, protected by tv_tpg_mutex */
 113         int tv_tpg_vhost_count;
 114         /* Used for enabling T10-PI with legacy devices */
 115         int tv_fabric_prot_type;
 116         /* list for vhost_scsi_list */
 117         struct list_head tv_tpg_list;
 118         /* Used to protect access for tpg_nexus */
 119         struct mutex tv_tpg_mutex;
 120         /* Pointer to the TCM VHost I_T Nexus for this TPG endpoint */
 121         struct vhost_scsi_nexus *tpg_nexus;
 122         /* Pointer back to vhost_scsi_tport */
 123         struct vhost_scsi_tport *tport;
 124         /* Returned by vhost_scsi_make_tpg() */
 125         struct se_portal_group se_tpg;
 126         /* Pointer back to vhost_scsi, protected by tv_tpg_mutex */
 127         struct vhost_scsi *vhost_scsi;
 128         struct list_head tmf_queue;
 129 };
 130
 131 struct vhost_scsi_tport {
 132         /* SCSI protocol the tport is providing */
 133         u8 tport_proto_id;
 134         /* Binary World Wide unique Port Name for Vhost Target port */
 135         u64 tport_wwpn;
 136         /* ASCII formatted WWPN for Vhost Target port */
 137         char tport_name[VHOST_SCSI_NAMELEN];
 138         /* Returned by vhost_scsi_make_tport() */
 139         struct se_wwn tport_wwn;
 140 };
 141
 142 struct vhost_scsi_evt {
 143         /* event to be sent to guest */
 144         struct virtio_scsi_event event;
 145         /* event list, serviced from vhost worker thread */
 146         struct llist_node list;
 147 };
 148
 149 enum {
 150         VHOST_SCSI_VQ_CTL = 0,
 151         VHOST_SCSI_VQ_EVT = 1,
 152         VHOST_SCSI_VQ_IO = 2,
 153 };
 154
 155 /* Note: can't set VIRTIO_F_VERSION_1 yet, since that implies ANY_LAYOUT. */
 156 enum {
 157         VHOST_SCSI_FEATURES = VHOST_FEATURES | (1ULL << VIRTIO_SCSI_F_HOTPLUG) |
 158                                                (1ULL << VIRTIO_SCSI_F_T10_PI)
 159 };
 160
 161 #define VHOST_SCSI_MAX_TARGET   256
 162 #define VHOST_SCSI_MAX_VQ       128
 163 #define VHOST_SCSI_MAX_EVENT    128
 164
 165 struct vhost_scsi_virtqueue {
 166         struct vhost_virtqueue vq;
 167         /*
 168          * Reference counting for inflight reqs, used for flush operation. At
 169          * each time, one reference tracks new commands submitted, while we
 170          * wait for another one to reach 0.
 171          */
 172         struct vhost_scsi_inflight inflights[2];
 173         /*
 174          * Indicate current inflight in use, protected by vq->mutex.
 175          * Writers must also take dev mutex and flush under it.
 176          */
 177         int inflight_idx;
 178         struct vhost_scsi_cmd *scsi_cmds;
 179         struct sbitmap scsi_tags;
 180         int max_cmds;
 181 };
 182
 183 struct vhost_scsi {
 184         /* Protected by vhost_scsi->dev.mutex */
 185         struct vhost_scsi_tpg **vs_tpg;
 186         char vs_vhost_wwpn[TRANSPORT_IQN_LEN];
 187
 188         struct vhost_dev dev;
 189         struct vhost_scsi_virtqueue vqs[VHOST_SCSI_MAX_VQ];
 190
 191         struct vhost_work vs_completion_work; /* cmd completion work item */
 192         struct llist_head vs_completion_list; /* cmd completion queue */
 193
 194         struct vhost_work vs_event_work; /* evt injection work item */
 195         struct llist_head vs_event_list; /* evt injection queue */
 196
 197         bool vs_events_missed; /* any missed events, protected by vq->mutex */
 198         int vs_events_nr; /* num of pending events, protected by vq->mutex */
 199 };
 200
 201 struct vhost_scsi_tmf {
 202         struct vhost_work vwork;
 203         struct vhost_scsi_tpg *tpg;
 204         struct vhost_scsi *vhost;
 205         struct vhost_scsi_virtqueue *svq;
 206         struct list_head queue_entry;
 207
 208         struct se_cmd se_cmd;
 209         u8 scsi_resp;
 210         struct vhost_scsi_inflight *inflight;
 211         struct iovec resp_iov;
 212         int in_iovs;
 213         int vq_desc;
 214 };
 215
 216 /*
 217  * Context for processing request and control queue operations.
 218  */
 219 struct vhost_scsi_ctx {
 220         int head;
 221         unsigned int out, in;
 222         size_t req_size, rsp_size;
 223         size_t out_size, in_size;
 224         u8 *target, *lunp;
 225         void *req;
 226         struct iov_iter out_iter;
 227 };
 228
 229 /* Global spinlock to protect vhost_scsi TPG list for vhost IOCTL access */
 230 static DEFINE_MUTEX(vhost_scsi_mutex);
 231 static LIST_HEAD(vhost_scsi_list);
 232
 233 static void vhost_scsi_done_inflight(struct kref *kref)
 234 {
 235         struct vhost_scsi_inflight *inflight;
 236
 237         inflight = container_of(kref, struct vhost_scsi_inflight, kref);
 238         complete(&inflight->comp);
 239 }
 240
 241 static void vhost_scsi_init_inflight(struct vhost_scsi *vs,
 242                                     struct vhost_scsi_inflight *old_inflight[])
 243 {
 244         struct vhost_scsi_inflight *new_inflight;
 245         struct vhost_virtqueue *vq;
 246         int idx, i;
 247
 248         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
 249                 vq = &vs->vqs[i].vq;
 250
 251                 mutex_lock(&vq->mutex);
 252
 253                 /* store old infight */
 254                 idx = vs->vqs[i].inflight_idx;
 255                 if (old_inflight)
 256                         old_inflight[i] = &vs->vqs[i].inflights[idx];
 257
 258                 /* setup new infight */
 259                 vs->vqs[i].inflight_idx = idx ^ 1;
 260                 new_inflight = &vs->vqs[i].inflights[idx ^ 1];
 261                 kref_init(&new_inflight->kref);
 262                 init_completion(&new_inflight->comp);
 263
 264                 mutex_unlock(&vq->mutex);
 265         }
 266 }
 267
 268 static struct vhost_scsi_inflight *
 269 vhost_scsi_get_inflight(struct vhost_virtqueue *vq)
 270 {
 271         struct vhost_scsi_inflight *inflight;
 272         struct vhost_scsi_virtqueue *svq;
 273
 274         svq = container_of(vq, struct vhost_scsi_virtqueue, vq);
 275         inflight = &svq->inflights[svq->inflight_idx];
 276         kref_get(&inflight->kref);
 277
 278         return inflight;
 279 }
 280
 281 static void vhost_scsi_put_inflight(struct vhost_scsi_inflight *inflight)
 282 {
 283         kref_put(&inflight->kref, vhost_scsi_done_inflight);
 284 }
 285
 286 static int vhost_scsi_check_true(struct se_portal_group *se_tpg)
 287 {
 288         return 1;
 289 }
 290
 291 static int vhost_scsi_check_false(struct se_portal_group *se_tpg)
 292 {
 293         return 0;
 294 }
 295
 296 static char *vhost_scsi_get_fabric_wwn(struct se_portal_group *se_tpg)
 297 {
 298         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 299                                 struct vhost_scsi_tpg, se_tpg);
 300         struct vhost_scsi_tport *tport = tpg->tport;
 301
 302         return &tport->tport_name[0];
 303 }
 304
 305 static u16 vhost_scsi_get_tpgt(struct se_portal_group *se_tpg)
 306 {
 307         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 308                                 struct vhost_scsi_tpg, se_tpg);
 309         return tpg->tport_tpgt;
 310 }
 311
 312 static int vhost_scsi_check_prot_fabric_only(struct se_portal_group *se_tpg)
 313 {
 314         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 315                                 struct vhost_scsi_tpg, se_tpg);
 316
 317         return tpg->tv_fabric_prot_type;
 318 }
 319
 320 static u32 vhost_scsi_tpg_get_inst_index(struct se_portal_group *se_tpg)
 321 {
 322         return 1;
 323 }
 324
 325 static void vhost_scsi_release_cmd_res(struct se_cmd *se_cmd)
 326 {
 327         struct vhost_scsi_cmd *tv_cmd = container_of(se_cmd,
 328                                 struct vhost_scsi_cmd, tvc_se_cmd);
 329         struct vhost_scsi_virtqueue *svq = container_of(tv_cmd->tvc_vq,
 330                                 struct vhost_scsi_virtqueue, vq);
 331         struct vhost_scsi_inflight *inflight = tv_cmd->inflight;
 332         int i;
 333
 334         if (tv_cmd->tvc_sgl_count) {
 335                 for (i = 0; i < tv_cmd->tvc_sgl_count; i++)
 336                         put_page(sg_page(&tv_cmd->tvc_sgl[i]));
 337         }
 338         if (tv_cmd->tvc_prot_sgl_count) {
 339                 for (i = 0; i < tv_cmd->tvc_prot_sgl_count; i++)
 340                         put_page(sg_page(&tv_cmd->tvc_prot_sgl[i]));
 341         }
 342
 343         sbitmap_clear_bit(&svq->scsi_tags, se_cmd->map_tag);
 344         vhost_scsi_put_inflight(inflight);
 345 }
 346
 347 static void vhost_scsi_release_tmf_res(struct vhost_scsi_tmf *tmf)
 348 {
 349         struct vhost_scsi_tpg *tpg = tmf->tpg;
 350         struct vhost_scsi_inflight *inflight = tmf->inflight;
 351
 352         mutex_lock(&tpg->tv_tpg_mutex);
 353         list_add_tail(&tpg->tmf_queue, &tmf->queue_entry);
 354         mutex_unlock(&tpg->tv_tpg_mutex);
 355         vhost_scsi_put_inflight(inflight);
 356 }
 357
 358 static void vhost_scsi_release_cmd(struct se_cmd *se_cmd)
 359 {
 360         if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB) {
 361                 struct vhost_scsi_tmf *tmf = container_of(se_cmd,
 362                                         struct vhost_scsi_tmf, se_cmd);
 363
 364                 vhost_work_queue(&tmf->vhost->dev, &tmf->vwork);
 365         } else {
 366                 struct vhost_scsi_cmd *cmd = container_of(se_cmd,
 367                                         struct vhost_scsi_cmd, tvc_se_cmd);
 368                 struct vhost_scsi *vs = cmd->tvc_vhost;
 369
 370                 llist_add(&cmd->tvc_completion_list, &vs->vs_completion_list);
 371                 vhost_work_queue(&vs->dev, &vs->vs_completion_work);
 372         }
 373 }
 374
 375 static u32 vhost_scsi_sess_get_index(struct se_session *se_sess)
 376 {
 377         return 0;
 378 }
 379
 380 static int vhost_scsi_write_pending(struct se_cmd *se_cmd)
 381 {
 382         /* Go ahead and process the write immediately */
 383         target_execute_cmd(se_cmd);
 384         return 0;
 385 }
 386
 387 static void vhost_scsi_set_default_node_attrs(struct se_node_acl *nacl)
 388 {
 389         return;
 390 }
 391
 392 static int vhost_scsi_get_cmd_state(struct se_cmd *se_cmd)
 393 {
 394         return 0;
 395 }
 396
 397 static int vhost_scsi_queue_data_in(struct se_cmd *se_cmd)
 398 {
 399         transport_generic_free_cmd(se_cmd, 0);
 400         return 0;
 401 }
 402
 403 static int vhost_scsi_queue_status(struct se_cmd *se_cmd)
 404 {
 405         transport_generic_free_cmd(se_cmd, 0);
 406         return 0;
 407 }
 408
 409 static void vhost_scsi_queue_tm_rsp(struct se_cmd *se_cmd)
 410 {
 411         struct vhost_scsi_tmf *tmf = container_of(se_cmd, struct vhost_scsi_tmf,
 412                                                   se_cmd);
 413
 414         tmf->scsi_resp = se_cmd->se_tmr_req->response;
 415         transport_generic_free_cmd(&tmf->se_cmd, 0);
 416 }
 417
 418 static void vhost_scsi_aborted_task(struct se_cmd *se_cmd)
 419 {
 420         return;
 421 }
 422
 423 static void vhost_scsi_free_evt(struct vhost_scsi *vs, struct vhost_scsi_evt *evt)
 424 {
 425         vs->vs_events_nr--;
 426         kfree(evt);
 427 }
 428
 429 static struct vhost_scsi_evt *
 430 vhost_scsi_allocate_evt(struct vhost_scsi *vs,
 431                        u32 event, u32 reason)
 432 {
 433         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 434         struct vhost_scsi_evt *evt;
 435
 436         if (vs->vs_events_nr > VHOST_SCSI_MAX_EVENT) {
 437                 vs->vs_events_missed = true;
 438                 return NULL;
 439         }
 440
 441         evt = kzalloc(sizeof(*evt), GFP_KERNEL);
 442         if (!evt) {
 443                 vq_err(vq, "Failed to allocate vhost_scsi_evt\n");
 444                 vs->vs_events_missed = true;
 445                 return NULL;
 446         }
 447
 448         evt->event.event = cpu_to_vhost32(vq, event);
 449         evt->event.reason = cpu_to_vhost32(vq, reason);
 450         vs->vs_events_nr++;
 451
 452         return evt;
 453 }
 454
 455 static int vhost_scsi_check_stop_free(struct se_cmd *se_cmd)
 456 {
 457         return target_put_sess_cmd(se_cmd);
 458 }
 459
 460 static void
 461 vhost_scsi_do_evt_work(struct vhost_scsi *vs, struct vhost_scsi_evt *evt)
 462 {
 463         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 464         struct virtio_scsi_event *event = &evt->event;
 465         struct virtio_scsi_event __user *eventp;
 466         unsigned out, in;
 467         int head, ret;
 468
 469         if (!vhost_vq_get_backend(vq)) {
 470                 vs->vs_events_missed = true;
 471                 return;
 472         }
 473
 474 again:
 475         vhost_disable_notify(&vs->dev, vq);
 476         head = vhost_get_vq_desc(vq, vq->iov,
 477                         ARRAY_SIZE(vq->iov), &out, &in,
 478                         NULL, NULL);
 479         if (head < 0) {
 480                 vs->vs_events_missed = true;
 481                 return;
 482         }
 483         if (head == vq->num) {
 484                 if (vhost_enable_notify(&vs->dev, vq))
 485                         goto again;
 486                 vs->vs_events_missed = true;
 487                 return;
 488         }
 489
 490         if ((vq->iov[out].iov_len != sizeof(struct virtio_scsi_event))) {
 491                 vq_err(vq, "Expecting virtio_scsi_event, got %zu bytes\n",
 492                                 vq->iov[out].iov_len);
 493                 vs->vs_events_missed = true;
 494                 return;
 495         }
 496
 497         if (vs->vs_events_missed) {
 498                 event->event |= cpu_to_vhost32(vq, VIRTIO_SCSI_T_EVENTS_MISSED);
 499                 vs->vs_events_missed = false;
 500         }
 501
 502         eventp = vq->iov[out].iov_base;
 503         ret = __copy_to_user(eventp, event, sizeof(*event));
 504         if (!ret)
 505                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 506         else
 507                 vq_err(vq, "Faulted on vhost_scsi_send_event\n");
 508 }
 509
 510 static void vhost_scsi_evt_work(struct vhost_work *work)
 511 {
 512         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 513                                         vs_event_work);
 514         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 515         struct vhost_scsi_evt *evt, *t;
 516         struct llist_node *llnode;
 517
 518         mutex_lock(&vq->mutex);
 519         llnode = llist_del_all(&vs->vs_event_list);
 520         llist_for_each_entry_safe(evt, t, llnode, list) {
 521                 vhost_scsi_do_evt_work(vs, evt);
 522                 vhost_scsi_free_evt(vs, evt);
 523         }
 524         mutex_unlock(&vq->mutex);
 525 }
 526
 527 /* Fill in status and signal that we are done processing this command
 528  *
 529  * This is scheduled in the vhost work queue so we are called with the owner
 530  * process mm and can access the vring.
 531  */
 532 static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
 533 {
 534         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 535                                         vs_completion_work);
 536         DECLARE_BITMAP(signal, VHOST_SCSI_MAX_VQ);
 537         struct virtio_scsi_cmd_resp v_rsp;
 538         struct vhost_scsi_cmd *cmd, *t;
 539         struct llist_node *llnode;
 540         struct se_cmd *se_cmd;
 541         struct iov_iter iov_iter;
 542         int ret, vq;
 543
 544         bitmap_zero(signal, VHOST_SCSI_MAX_VQ);
 545         llnode = llist_del_all(&vs->vs_completion_list);
 546         llist_for_each_entry_safe(cmd, t, llnode, tvc_completion_list) {
 547                 se_cmd = &cmd->tvc_se_cmd;
 548
 549                 pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__,
 550                         cmd, se_cmd->residual_count, se_cmd->scsi_status);
 551
 552                 memset(&v_rsp, 0, sizeof(v_rsp));
 553                 v_rsp.resid = cpu_to_vhost32(cmd->tvc_vq, se_cmd->residual_count);
 554                 /* TODO is status_qualifier field needed? */
 555                 v_rsp.status = se_cmd->scsi_status;
 556                 v_rsp.sense_len = cpu_to_vhost32(cmd->tvc_vq,
 557                                                  se_cmd->scsi_sense_length);
 558                 memcpy(v_rsp.sense, cmd->tvc_sense_buf,
 559                        se_cmd->scsi_sense_length);
 560
 561                 iov_iter_init(&iov_iter, READ, &cmd->tvc_resp_iov,
 562                               cmd->tvc_in_iovs, sizeof(v_rsp));
 563                 ret = copy_to_iter(&v_rsp, sizeof(v_rsp), &iov_iter);
 564                 if (likely(ret == sizeof(v_rsp))) {
 565                         struct vhost_scsi_virtqueue *q;
 566                         vhost_add_used(cmd->tvc_vq, cmd->tvc_vq_desc, 0);
 567                         q = container_of(cmd->tvc_vq, struct vhost_scsi_virtqueue, vq);
 568                         vq = q - vs->vqs;
 569                         __set_bit(vq, signal);
 570                 } else
 571                         pr_err("Faulted on virtio_scsi_cmd_resp\n");
 572
 573                 vhost_scsi_release_cmd_res(se_cmd);
 574         }
 575
 576         vq = -1;
 577         while ((vq = find_next_bit(signal, VHOST_SCSI_MAX_VQ, vq + 1))
 578                 < VHOST_SCSI_MAX_VQ)
 579                 vhost_signal(&vs->dev, &vs->vqs[vq].vq);
 580 }
 581
 582 static struct vhost_scsi_cmd *
 583 vhost_scsi_get_cmd(struct vhost_virtqueue *vq, struct vhost_scsi_tpg *tpg,
 584                    unsigned char *cdb, u64 scsi_tag, u16 lun, u8 task_attr,
 585                    u32 exp_data_len, int data_direction)
 586 {
 587         struct vhost_scsi_virtqueue *svq = container_of(vq,
 588                                         struct vhost_scsi_virtqueue, vq);
 589         struct vhost_scsi_cmd *cmd;
 590         struct vhost_scsi_nexus *tv_nexus;
 591         struct scatterlist *sg, *prot_sg;
 592         struct page **pages;
 593         int tag;
 594
 595         tv_nexus = tpg->tpg_nexus;
 596         if (!tv_nexus) {
 597                 pr_err("Unable to locate active struct vhost_scsi_nexus\n");
 598                 return ERR_PTR(-EIO);
 599         }
 600
 601         tag = sbitmap_get(&svq->scsi_tags);
 602         if (tag < 0) {
 603                 pr_err("Unable to obtain tag for vhost_scsi_cmd\n");
 604                 return ERR_PTR(-ENOMEM);
 605         }
 606
 607         cmd = &svq->scsi_cmds[tag];
 608         sg = cmd->tvc_sgl;
 609         prot_sg = cmd->tvc_prot_sgl;
 610         pages = cmd->tvc_upages;
 611         memset(cmd, 0, sizeof(*cmd));
 612         cmd->tvc_sgl = sg;
 613         cmd->tvc_prot_sgl = prot_sg;
 614         cmd->tvc_upages = pages;
 615         cmd->tvc_se_cmd.map_tag = tag;
 616         cmd->tvc_tag = scsi_tag;
 617         cmd->tvc_lun = lun;
 618         cmd->tvc_task_attr = task_attr;
 619         cmd->tvc_exp_data_len = exp_data_len;
 620         cmd->tvc_data_direction = data_direction;
 621         cmd->tvc_nexus = tv_nexus;
 622         cmd->inflight = vhost_scsi_get_inflight(vq);
 623
 624         memcpy(cmd->tvc_cdb, cdb, VHOST_SCSI_MAX_CDB_SIZE);
 625
 626         return cmd;
 627 }
 628
 629 /*
 630  * Map a user memory range into a scatterlist
 631  *
 632  * Returns the number of scatterlist entries used or -errno on error.
 633  */
 634 static int
 635 vhost_scsi_map_to_sgl(struct vhost_scsi_cmd *cmd,
 636                       struct iov_iter *iter,
 637                       struct scatterlist *sgl,
 638                       bool write)
 639 {
 640         struct page **pages = cmd->tvc_upages;
 641         struct scatterlist *sg = sgl;
 642         ssize_t bytes;
 643         size_t offset;
 644         unsigned int npages = 0;
 645
 646         bytes = iov_iter_get_pages2(iter, pages, LONG_MAX,
 647                                 VHOST_SCSI_PREALLOC_UPAGES, &offset);
 648         /* No pages were pinned */
 649         if (bytes <= 0)
 650                 return bytes < 0 ? bytes : -EFAULT;
 651
 652         while (bytes) {
 653                 unsigned n = min_t(unsigned, PAGE_SIZE - offset, bytes);
 654                 sg_set_page(sg++, pages[npages++], n, offset);
 655                 bytes -= n;
 656                 offset = 0;
 657         }
 658         return npages;
 659 }
 660
 661 static int
 662 vhost_scsi_calc_sgls(struct iov_iter *iter, size_t bytes, int max_sgls)
 663 {
 664         int sgl_count = 0;
 665
 666         if (!iter || !iter->iov) {
 667                 pr_err("%s: iter->iov is NULL, but expected bytes: %zu"
 668                        " present\n", __func__, bytes);
 669                 return -EINVAL;
 670         }
 671
 672         sgl_count = iov_iter_npages(iter, 0xffff);
 673         if (sgl_count > max_sgls) {
 674                 pr_err("%s: requested sgl_count: %d exceeds pre-allocated"
 675                        " max_sgls: %d\n", __func__, sgl_count, max_sgls);
 676                 return -EINVAL;
 677         }
 678         return sgl_count;
 679 }
 680
 681 static int
 682 vhost_scsi_iov_to_sgl(struct vhost_scsi_cmd *cmd, bool write,
 683                       struct iov_iter *iter,
 684                       struct scatterlist *sg, int sg_count)
 685 {
 686         struct scatterlist *p = sg;
 687         int ret;
 688
 689         while (iov_iter_count(iter)) {
 690                 ret = vhost_scsi_map_to_sgl(cmd, iter, sg, write);
 691                 if (ret < 0) {
 692                         while (p < sg) {
 693                                 struct page *page = sg_page(p++);
 694                                 if (page)
 695                                         put_page(page);
 696                         }
 697                         return ret;
 698                 }
 699                 sg += ret;
 700         }
 701         return 0;
 702 }
 703
 704 static int
 705 vhost_scsi_mapal(struct vhost_scsi_cmd *cmd,
 706                  size_t prot_bytes, struct iov_iter *prot_iter,
 707                  size_t data_bytes, struct iov_iter *data_iter)
 708 {
 709         int sgl_count, ret;
 710         bool write = (cmd->tvc_data_direction == DMA_FROM_DEVICE);
 711
 712         if (prot_bytes) {
 713                 sgl_count = vhost_scsi_calc_sgls(prot_iter, prot_bytes,
 714                                                  VHOST_SCSI_PREALLOC_PROT_SGLS);
 715                 if (sgl_count < 0)
 716                         return sgl_count;
 717
 718                 sg_init_table(cmd->tvc_prot_sgl, sgl_count);
 719                 cmd->tvc_prot_sgl_count = sgl_count;
 720                 pr_debug("%s prot_sg %p prot_sgl_count %u\n", __func__,
 721                          cmd->tvc_prot_sgl, cmd->tvc_prot_sgl_count);
 722
 723                 ret = vhost_scsi_iov_to_sgl(cmd, write, prot_iter,
 724                                             cmd->tvc_prot_sgl,
 725                                             cmd->tvc_prot_sgl_count);
 726                 if (ret < 0) {
 727                         cmd->tvc_prot_sgl_count = 0;
 728                         return ret;
 729                 }
 730         }
 731         sgl_count = vhost_scsi_calc_sgls(data_iter, data_bytes,
 732                                          VHOST_SCSI_PREALLOC_SGLS);
 733         if (sgl_count < 0)
 734                 return sgl_count;
 735
 736         sg_init_table(cmd->tvc_sgl, sgl_count);
 737         cmd->tvc_sgl_count = sgl_count;
 738         pr_debug("%s data_sg %p data_sgl_count %u\n", __func__,
 739                   cmd->tvc_sgl, cmd->tvc_sgl_count);
 740
 741         ret = vhost_scsi_iov_to_sgl(cmd, write, data_iter,
 742                                     cmd->tvc_sgl, cmd->tvc_sgl_count);
 743         if (ret < 0) {
 744                 cmd->tvc_sgl_count = 0;
 745                 return ret;
 746         }
 747         return 0;
 748 }
 749
 750 static int vhost_scsi_to_tcm_attr(int attr)
 751 {
 752         switch (attr) {
 753         case VIRTIO_SCSI_S_SIMPLE:
 754                 return TCM_SIMPLE_TAG;
 755         case VIRTIO_SCSI_S_ORDERED:
 756                 return TCM_ORDERED_TAG;
 757         case VIRTIO_SCSI_S_HEAD:
 758                 return TCM_HEAD_TAG;
 759         case VIRTIO_SCSI_S_ACA:
 760                 return TCM_ACA_TAG;
 761         default:
 762                 break;
 763         }
 764         return TCM_SIMPLE_TAG;
 765 }
 766
 767 static void vhost_scsi_target_queue_cmd(struct vhost_scsi_cmd *cmd)
 768 {
 769         struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
 770         struct vhost_scsi_nexus *tv_nexus;
 771         struct scatterlist *sg_ptr, *sg_prot_ptr = NULL;
 772
 773         /* FIXME: BIDI operation */
 774         if (cmd->tvc_sgl_count) {
 775                 sg_ptr = cmd->tvc_sgl;
 776
 777                 if (cmd->tvc_prot_sgl_count)
 778                         sg_prot_ptr = cmd->tvc_prot_sgl;
 779                 else
 780                         se_cmd->prot_pto = true;
 781         } else {
 782                 sg_ptr = NULL;
 783         }
 784         tv_nexus = cmd->tvc_nexus;
 785
 786         se_cmd->tag = 0;
 787         target_init_cmd(se_cmd, tv_nexus->tvn_se_sess, &cmd->tvc_sense_buf[0],
 788                         cmd->tvc_lun, cmd->tvc_exp_data_len,
 789                         vhost_scsi_to_tcm_attr(cmd->tvc_task_attr),
 790                         cmd->tvc_data_direction, TARGET_SCF_ACK_KREF);
 791
 792         if (target_submit_prep(se_cmd, cmd->tvc_cdb, sg_ptr,
 793                                cmd->tvc_sgl_count, NULL, 0, sg_prot_ptr,
 794                                cmd->tvc_prot_sgl_count, GFP_KERNEL))
 795                 return;
 796
 797         target_queue_submission(se_cmd);
 798 }
 799
 800 static void
 801 vhost_scsi_send_bad_target(struct vhost_scsi *vs,
 802                            struct vhost_virtqueue *vq,
 803                            int head, unsigned out)
 804 {
 805         struct virtio_scsi_cmd_resp __user *resp;
 806         struct virtio_scsi_cmd_resp rsp;
 807         int ret;
 808
 809         memset(&rsp, 0, sizeof(rsp));
 810         rsp.response = VIRTIO_SCSI_S_BAD_TARGET;
 811         resp = vq->iov[out].iov_base;
 812         ret = __copy_to_user(resp, &rsp, sizeof(rsp));
 813         if (!ret)
 814                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 815         else
 816                 pr_err("Faulted on virtio_scsi_cmd_resp\n");
 817 }
 818
 819 static int
 820 vhost_scsi_get_desc(struct vhost_scsi *vs, struct vhost_virtqueue *vq,
 821                     struct vhost_scsi_ctx *vc)
 822 {
 823         int ret = -ENXIO;
 824
 825         vc->head = vhost_get_vq_desc(vq, vq->iov,
 826                                      ARRAY_SIZE(vq->iov), &vc->out, &vc->in,
 827                                      NULL, NULL);
 828
 829         pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n",
 830                  vc->head, vc->out, vc->in);
 831
 832         /* On error, stop handling until the next kick. */
 833         if (unlikely(vc->head < 0))
 834                 goto done;
 835
 836         /* Nothing new?  Wait for eventfd to tell us they refilled. */
 837         if (vc->head == vq->num) {
 838                 if (unlikely(vhost_enable_notify(&vs->dev, vq))) {
 839                         vhost_disable_notify(&vs->dev, vq);
 840                         ret = -EAGAIN;
 841                 }
 842                 goto done;
 843         }
 844
 845         /*
 846          * Get the size of request and response buffers.
 847          * FIXME: Not correct for BIDI operation
 848          */
 849         vc->out_size = iov_length(vq->iov, vc->out);
 850         vc->in_size = iov_length(&vq->iov[vc->out], vc->in);
 851
 852         /*
 853          * Copy over the virtio-scsi request header, which for a
 854          * ANY_LAYOUT enabled guest may span multiple iovecs, or a
 855          * single iovec may contain both the header + outgoing
 856          * WRITE payloads.
 857          *
 858          * copy_from_iter() will advance out_iter, so that it will
 859          * point at the start of the outgoing WRITE payload, if
 860          * DMA_TO_DEVICE is set.
 861          */
 862         iov_iter_init(&vc->out_iter, WRITE, vq->iov, vc->out, vc->out_size);
 863         ret = 0;
 864
 865 done:
 866         return ret;
 867 }
 868
 869 static int
 870 vhost_scsi_chk_size(struct vhost_virtqueue *vq, struct vhost_scsi_ctx *vc)
 871 {
 872         if (unlikely(vc->in_size < vc->rsp_size)) {
 873                 vq_err(vq,
 874                        "Response buf too small, need min %zu bytes got %zu",
 875                        vc->rsp_size, vc->in_size);
 876                 return -EINVAL;
 877         } else if (unlikely(vc->out_size < vc->req_size)) {
 878                 vq_err(vq,
 879                        "Request buf too small, need min %zu bytes got %zu",
 880                        vc->req_size, vc->out_size);
 881                 return -EIO;
 882         }
 883
 884         return 0;
 885 }
 886
 887 static int
 888 vhost_scsi_get_req(struct vhost_virtqueue *vq, struct vhost_scsi_ctx *vc,
 889                    struct vhost_scsi_tpg **tpgp)
 890 {
 891         int ret = -EIO;
 892
 893         if (unlikely(!copy_from_iter_full(vc->req, vc->req_size,
 894                                           &vc->out_iter))) {
 895                 vq_err(vq, "Faulted on copy_from_iter_full\n");
 896         } else if (unlikely(*vc->lunp != 1)) {
 897                 /* virtio-scsi spec requires byte 0 of the lun to be 1 */
 898                 vq_err(vq, "Illegal virtio-scsi lun: %u\n", *vc->lunp);
 899         } else {
 900                 struct vhost_scsi_tpg **vs_tpg, *tpg;
 901
 902                 vs_tpg = vhost_vq_get_backend(vq);      /* validated at handler entry */
 903
 904                 tpg = READ_ONCE(vs_tpg[*vc->target]);
 905                 if (unlikely(!tpg)) {
 906                         vq_err(vq, "Target 0x%x does not exist\n", *vc->target);
 907                 } else {
 908                         if (tpgp)
 909                                 *tpgp = tpg;
 910                         ret = 0;
 911                 }
 912         }
 913
 914         return ret;
 915 }
 916
 917 static u16 vhost_buf_to_lun(u8 *lun_buf)
 918 {
 919         return ((lun_buf[2] << 8) | lun_buf[3]) & 0x3FFF;
 920 }
 921
 922 static void
 923 vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
 924 {
 925         struct vhost_scsi_tpg **vs_tpg, *tpg;
 926         struct virtio_scsi_cmd_req v_req;
 927         struct virtio_scsi_cmd_req_pi v_req_pi;
 928         struct vhost_scsi_ctx vc;
 929         struct vhost_scsi_cmd *cmd;
 930         struct iov_iter in_iter, prot_iter, data_iter;
 931         u64 tag;
 932         u32 exp_data_len, data_direction;
 933         int ret, prot_bytes, c = 0;
 934         u16 lun;
 935         u8 task_attr;
 936         bool t10_pi = vhost_has_feature(vq, VIRTIO_SCSI_F_T10_PI);
 937         void *cdb;
 938
 939         mutex_lock(&vq->mutex);
 940         /*
 941          * We can handle the vq only after the endpoint is setup by calling the
 942          * VHOST_SCSI_SET_ENDPOINT ioctl.
 943          */
 944         vs_tpg = vhost_vq_get_backend(vq);
 945         if (!vs_tpg)
 946                 goto out;
 947
 948         memset(&vc, 0, sizeof(vc));
 949         vc.rsp_size = sizeof(struct virtio_scsi_cmd_resp);
 950
 951         vhost_disable_notify(&vs->dev, vq);
 952
 953         do {
 954                 ret = vhost_scsi_get_desc(vs, vq, &vc);
 955                 if (ret)
 956                         goto err;
 957
 958                 /*
 959                  * Setup pointers and values based upon different virtio-scsi
 960                  * request header if T10_PI is enabled in KVM guest.
 961                  */
 962                 if (t10_pi) {
 963                         vc.req = &v_req_pi;
 964                         vc.req_size = sizeof(v_req_pi);
 965                         vc.lunp = &v_req_pi.lun[0];
 966                         vc.target = &v_req_pi.lun[1];
 967                 } else {
 968                         vc.req = &v_req;
 969                         vc.req_size = sizeof(v_req);
 970                         vc.lunp = &v_req.lun[0];
 971                         vc.target = &v_req.lun[1];
 972                 }
 973
 974                 /*
 975                  * Validate the size of request and response buffers.
 976                  * Check for a sane response buffer so we can report
 977                  * early errors back to the guest.
 978                  */
 979                 ret = vhost_scsi_chk_size(vq, &vc);
 980                 if (ret)
 981                         goto err;
 982
 983                 ret = vhost_scsi_get_req(vq, &vc, &tpg);
 984                 if (ret)
 985                         goto err;
 986
 987                 ret = -EIO;     /* bad target on any error from here on */
 988
 989                 /*
 990                  * Determine data_direction by calculating the total outgoing
 991                  * iovec sizes + incoming iovec sizes vs. virtio-scsi request +
 992                  * response headers respectively.
 993                  *
 994                  * For DMA_TO_DEVICE this is out_iter, which is already pointing
 995                  * to the right place.
 996                  *
 997                  * For DMA_FROM_DEVICE, the iovec will be just past the end
 998                  * of the virtio-scsi response header in either the same
 999                  * or immediately following iovec.
1000                  *
1001                  * Any associated T10_PI bytes for the outgoing / incoming
1002                  * payloads are included in calculation of exp_data_len here.
1003                  */
1004                 prot_bytes = 0;
1005
1006                 if (vc.out_size > vc.req_size) {
1007                         data_direction = DMA_TO_DEVICE;
1008                         exp_data_len = vc.out_size - vc.req_size;
1009                         data_iter = vc.out_iter;
1010                 } else if (vc.in_size > vc.rsp_size) {
1011                         data_direction = DMA_FROM_DEVICE;
1012                         exp_data_len = vc.in_size - vc.rsp_size;
1013
1014                         iov_iter_init(&in_iter, READ, &vq->iov[vc.out], vc.in,
1015                                       vc.rsp_size + exp_data_len);
1016                         iov_iter_advance(&in_iter, vc.rsp_size);
1017                         data_iter = in_iter;
1018                 } else {
1019                         data_direction = DMA_NONE;
1020                         exp_data_len = 0;
1021                 }
1022                 /*
1023                  * If T10_PI header + payload is present, setup prot_iter values
1024                  * and recalculate data_iter for vhost_scsi_mapal() mapping to
1025                  * host scatterlists via get_user_pages_fast().
1026                  */
1027                 if (t10_pi) {
1028                         if (v_req_pi.pi_bytesout) {
1029                                 if (data_direction != DMA_TO_DEVICE) {
1030                                         vq_err(vq, "Received non zero pi_bytesout,"
1031                                                 " but wrong data_direction\n");
1032                                         goto err;
1033                                 }
1034                                 prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesout);
1035                         } else if (v_req_pi.pi_bytesin) {
1036                                 if (data_direction != DMA_FROM_DEVICE) {
1037                                         vq_err(vq, "Received non zero pi_bytesin,"
1038                                                 " but wrong data_direction\n");
1039                                         goto err;
1040                                 }
1041                                 prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesin);
1042                         }
1043                         /*
1044                          * Set prot_iter to data_iter and truncate it to
1045                          * prot_bytes, and advance data_iter past any
1046                          * preceeding prot_bytes that may be present.
1047                          *
1048                          * Also fix up the exp_data_len to reflect only the
1049                          * actual data payload length.
1050                          */
1051                         if (prot_bytes) {
1052                                 exp_data_len -= prot_bytes;
1053                                 prot_iter = data_iter;
1054                                 iov_iter_truncate(&prot_iter, prot_bytes);
1055                                 iov_iter_advance(&data_iter, prot_bytes);
1056                         }
1057                         tag = vhost64_to_cpu(vq, v_req_pi.tag);
1058                         task_attr = v_req_pi.task_attr;
1059                         cdb = &v_req_pi.cdb[0];
1060                         lun = vhost_buf_to_lun(v_req_pi.lun);
1061                 } else {
1062                         tag = vhost64_to_cpu(vq, v_req.tag);
1063                         task_attr = v_req.task_attr;
1064                         cdb = &v_req.cdb[0];
1065                         lun = vhost_buf_to_lun(v_req.lun);
1066                 }
1067                 /*
1068                  * Check that the received CDB size does not exceeded our
1069                  * hardcoded max for vhost-scsi, then get a pre-allocated
1070                  * cmd descriptor for the new virtio-scsi tag.
1071                  *
1072                  * TODO what if cdb was too small for varlen cdb header?
1073                  */
1074                 if (unlikely(scsi_command_size(cdb) > VHOST_SCSI_MAX_CDB_SIZE)) {
1075                         vq_err(vq, "Received SCSI CDB with command_size: %d that"
1076                                 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1077                                 scsi_command_size(cdb), VHOST_SCSI_MAX_CDB_SIZE);
1078                                 goto err;
1079                 }
1080                 cmd = vhost_scsi_get_cmd(vq, tpg, cdb, tag, lun, task_attr,
1081                                          exp_data_len + prot_bytes,
1082                                          data_direction);
1083                 if (IS_ERR(cmd)) {
1084                         vq_err(vq, "vhost_scsi_get_cmd failed %ld\n",
1085                                PTR_ERR(cmd));
1086                         goto err;
1087                 }
1088                 cmd->tvc_vhost = vs;
1089                 cmd->tvc_vq = vq;
1090                 cmd->tvc_resp_iov = vq->iov[vc.out];
1091                 cmd->tvc_in_iovs = vc.in;
1092
1093                 pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n",
1094                          cmd->tvc_cdb[0], cmd->tvc_lun);
1095                 pr_debug("cmd: %p exp_data_len: %d, prot_bytes: %d data_direction:"
1096                          " %d\n", cmd, exp_data_len, prot_bytes, data_direction);
1097
1098                 if (data_direction != DMA_NONE) {
1099                         if (unlikely(vhost_scsi_mapal(cmd, prot_bytes,
1100                                                       &prot_iter, exp_data_len,
1101                                                       &data_iter))) {
1102                                 vq_err(vq, "Failed to map iov to sgl\n");
1103                                 vhost_scsi_release_cmd_res(&cmd->tvc_se_cmd);
1104                                 goto err;
1105                         }
1106                 }
1107                 /*
1108                  * Save the descriptor from vhost_get_vq_desc() to be used to
1109                  * complete the virtio-scsi request in TCM callback context via
1110                  * vhost_scsi_queue_data_in() and vhost_scsi_queue_status()
1111                  */
1112                 cmd->tvc_vq_desc = vc.head;
1113                 vhost_scsi_target_queue_cmd(cmd);
1114                 ret = 0;
1115 err:
1116                 /*
1117                  * ENXIO:  No more requests, or read error, wait for next kick
1118                  * EINVAL: Invalid response buffer, drop the request
1119                  * EIO:    Respond with bad target
1120                  * EAGAIN: Pending request
1121                  */
1122                 if (ret == -ENXIO)
1123                         break;
1124                 else if (ret == -EIO)
1125                         vhost_scsi_send_bad_target(vs, vq, vc.head, vc.out);
1126         } while (likely(!vhost_exceeds_weight(vq, ++c, 0)));
1127 out:
1128         mutex_unlock(&vq->mutex);
1129 }
1130
1131 static void
1132 vhost_scsi_send_tmf_resp(struct vhost_scsi *vs, struct vhost_virtqueue *vq,
1133                          int in_iovs, int vq_desc, struct iovec *resp_iov,
1134                          int tmf_resp_code)
1135 {
1136         struct virtio_scsi_ctrl_tmf_resp rsp;
1137         struct iov_iter iov_iter;
1138         int ret;
1139
1140         pr_debug("%s\n", __func__);
1141         memset(&rsp, 0, sizeof(rsp));
1142         rsp.response = tmf_resp_code;
1143
1144         iov_iter_init(&iov_iter, READ, resp_iov, in_iovs, sizeof(rsp));
1145
1146         ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter);
1147         if (likely(ret == sizeof(rsp)))
1148                 vhost_add_used_and_signal(&vs->dev, vq, vq_desc, 0);
1149         else
1150                 pr_err("Faulted on virtio_scsi_ctrl_tmf_resp\n");
1151 }
1152
1153 static void vhost_scsi_tmf_resp_work(struct vhost_work *work)
1154 {
1155         struct vhost_scsi_tmf *tmf = container_of(work, struct vhost_scsi_tmf,
1156                                                   vwork);
1157         int resp_code;
1158
1159         if (tmf->scsi_resp == TMR_FUNCTION_COMPLETE)
1160                 resp_code = VIRTIO_SCSI_S_FUNCTION_SUCCEEDED;
1161         else
1162                 resp_code = VIRTIO_SCSI_S_FUNCTION_REJECTED;
1163
1164         vhost_scsi_send_tmf_resp(tmf->vhost, &tmf->svq->vq, tmf->in_iovs,
1165                                  tmf->vq_desc, &tmf->resp_iov, resp_code);
1166         vhost_scsi_release_tmf_res(tmf);
1167 }
1168
1169 static void
1170 vhost_scsi_handle_tmf(struct vhost_scsi *vs, struct vhost_scsi_tpg *tpg,
1171                       struct vhost_virtqueue *vq,
1172                       struct virtio_scsi_ctrl_tmf_req *vtmf,
1173                       struct vhost_scsi_ctx *vc)
1174 {
1175         struct vhost_scsi_virtqueue *svq = container_of(vq,
1176                                         struct vhost_scsi_virtqueue, vq);
1177         struct vhost_scsi_tmf *tmf;
1178
1179         if (vhost32_to_cpu(vq, vtmf->subtype) !=
1180             VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET)
1181                 goto send_reject;
1182
1183         if (!tpg->tpg_nexus || !tpg->tpg_nexus->tvn_se_sess) {
1184                 pr_err("Unable to locate active struct vhost_scsi_nexus for LUN RESET.\n");
1185                 goto send_reject;
1186         }
1187
1188         mutex_lock(&tpg->tv_tpg_mutex);
1189         if (list_empty(&tpg->tmf_queue)) {
1190                 pr_err("Missing reserve TMF. Could not handle LUN RESET.\n");
1191                 mutex_unlock(&tpg->tv_tpg_mutex);
1192                 goto send_reject;
1193         }
1194
1195         tmf = list_first_entry(&tpg->tmf_queue, struct vhost_scsi_tmf,
1196                                queue_entry);
1197         list_del_init(&tmf->queue_entry);
1198         mutex_unlock(&tpg->tv_tpg_mutex);
1199
1200         tmf->tpg = tpg;
1201         tmf->vhost = vs;
1202         tmf->svq = svq;
1203         tmf->resp_iov = vq->iov[vc->out];
1204         tmf->vq_desc = vc->head;
1205         tmf->in_iovs = vc->in;
1206         tmf->inflight = vhost_scsi_get_inflight(vq);
1207
1208         if (target_submit_tmr(&tmf->se_cmd, tpg->tpg_nexus->tvn_se_sess, NULL,
1209                               vhost_buf_to_lun(vtmf->lun), NULL,
1210                               TMR_LUN_RESET, GFP_KERNEL, 0,
1211                               TARGET_SCF_ACK_KREF) < 0) {
1212                 vhost_scsi_release_tmf_res(tmf);
1213                 goto send_reject;
1214         }
1215
1216         return;
1217
1218 send_reject:
1219         vhost_scsi_send_tmf_resp(vs, vq, vc->in, vc->head, &vq->iov[vc->out],
1220                                  VIRTIO_SCSI_S_FUNCTION_REJECTED);
1221 }
1222
1223 static void
1224 vhost_scsi_send_an_resp(struct vhost_scsi *vs,
1225                         struct vhost_virtqueue *vq,
1226                         struct vhost_scsi_ctx *vc)
1227 {
1228         struct virtio_scsi_ctrl_an_resp rsp;
1229         struct iov_iter iov_iter;
1230         int ret;
1231
1232         pr_debug("%s\n", __func__);
1233         memset(&rsp, 0, sizeof(rsp));   /* event_actual = 0 */
1234         rsp.response = VIRTIO_SCSI_S_OK;
1235
1236         iov_iter_init(&iov_iter, READ, &vq->iov[vc->out], vc->in, sizeof(rsp));
1237
1238         ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter);
1239         if (likely(ret == sizeof(rsp)))
1240                 vhost_add_used_and_signal(&vs->dev, vq, vc->head, 0);
1241         else
1242                 pr_err("Faulted on virtio_scsi_ctrl_an_resp\n");
1243 }
1244
1245 static void
1246 vhost_scsi_ctl_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
1247 {
1248         struct vhost_scsi_tpg *tpg;
1249         union {
1250                 __virtio32 type;
1251                 struct virtio_scsi_ctrl_an_req an;
1252                 struct virtio_scsi_ctrl_tmf_req tmf;
1253         } v_req;
1254         struct vhost_scsi_ctx vc;
1255         size_t typ_size;
1256         int ret, c = 0;
1257
1258         mutex_lock(&vq->mutex);
1259         /*
1260          * We can handle the vq only after the endpoint is setup by calling the
1261          * VHOST_SCSI_SET_ENDPOINT ioctl.
1262          */
1263         if (!vhost_vq_get_backend(vq))
1264                 goto out;
1265
1266         memset(&vc, 0, sizeof(vc));
1267
1268         vhost_disable_notify(&vs->dev, vq);
1269
1270         do {
1271                 ret = vhost_scsi_get_desc(vs, vq, &vc);
1272                 if (ret)
1273                         goto err;
1274
1275                 /*
1276                  * Get the request type first in order to setup
1277                  * other parameters dependent on the type.
1278                  */
1279                 vc.req = &v_req.type;
1280                 typ_size = sizeof(v_req.type);
1281
1282                 if (unlikely(!copy_from_iter_full(vc.req, typ_size,
1283                                                   &vc.out_iter))) {
1284                         vq_err(vq, "Faulted on copy_from_iter tmf type\n");
1285                         /*
1286                          * The size of the response buffer depends on the
1287                          * request type and must be validated against it.
1288                          * Since the request type is not known, don't send
1289                          * a response.
1290                          */
1291                         continue;
1292                 }
1293
1294                 switch (vhost32_to_cpu(vq, v_req.type)) {
1295                 case VIRTIO_SCSI_T_TMF:
1296                         vc.req = &v_req.tmf;
1297                         vc.req_size = sizeof(struct virtio_scsi_ctrl_tmf_req);
1298                         vc.rsp_size = sizeof(struct virtio_scsi_ctrl_tmf_resp);
1299                         vc.lunp = &v_req.tmf.lun[0];
1300                         vc.target = &v_req.tmf.lun[1];
1301                         break;
1302                 case VIRTIO_SCSI_T_AN_QUERY:
1303                 case VIRTIO_SCSI_T_AN_SUBSCRIBE:
1304                         vc.req = &v_req.an;
1305                         vc.req_size = sizeof(struct virtio_scsi_ctrl_an_req);
1306                         vc.rsp_size = sizeof(struct virtio_scsi_ctrl_an_resp);
1307                         vc.lunp = &v_req.an.lun[0];
1308                         vc.target = NULL;
1309                         break;
1310                 default:
1311                         vq_err(vq, "Unknown control request %d", v_req.type);
1312                         continue;
1313                 }
1314
1315                 /*
1316                  * Validate the size of request and response buffers.
1317                  * Check for a sane response buffer so we can report
1318                  * early errors back to the guest.
1319                  */
1320                 ret = vhost_scsi_chk_size(vq, &vc);
1321                 if (ret)
1322                         goto err;
1323
1324                 /*
1325                  * Get the rest of the request now that its size is known.
1326                  */
1327                 vc.req += typ_size;
1328                 vc.req_size -= typ_size;
1329
1330                 ret = vhost_scsi_get_req(vq, &vc, &tpg);
1331                 if (ret)
1332                         goto err;
1333
1334                 if (v_req.type == VIRTIO_SCSI_T_TMF)
1335                         vhost_scsi_handle_tmf(vs, tpg, vq, &v_req.tmf, &vc);
1336                 else
1337                         vhost_scsi_send_an_resp(vs, vq, &vc);
1338 err:
1339                 /*
1340                  * ENXIO:  No more requests, or read error, wait for next kick
1341                  * EINVAL: Invalid response buffer, drop the request
1342                  * EIO:    Respond with bad target
1343                  * EAGAIN: Pending request
1344                  */
1345                 if (ret == -ENXIO)
1346                         break;
1347                 else if (ret == -EIO)
1348                         vhost_scsi_send_bad_target(vs, vq, vc.head, vc.out);
1349         } while (likely(!vhost_exceeds_weight(vq, ++c, 0)));
1350 out:
1351         mutex_unlock(&vq->mutex);
1352 }
1353
1354 static void vhost_scsi_ctl_handle_kick(struct vhost_work *work)
1355 {
1356         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1357                                                 poll.work);
1358         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1359
1360         pr_debug("%s: The handling func for control queue.\n", __func__);
1361         vhost_scsi_ctl_handle_vq(vs, vq);
1362 }
1363
1364 static void
1365 vhost_scsi_send_evt(struct vhost_scsi *vs,
1366                    struct vhost_scsi_tpg *tpg,
1367                    struct se_lun *lun,
1368                    u32 event,
1369                    u32 reason)
1370 {
1371         struct vhost_scsi_evt *evt;
1372
1373         evt = vhost_scsi_allocate_evt(vs, event, reason);
1374         if (!evt)
1375                 return;
1376
1377         if (tpg && lun) {
1378                 /* TODO: share lun setup code with virtio-scsi.ko */
1379                 /*
1380                  * Note: evt->event is zeroed when we allocate it and
1381                  * lun[4-7] need to be zero according to virtio-scsi spec.
1382                  */
1383                 evt->event.lun[0] = 0x01;
1384                 evt->event.lun[1] = tpg->tport_tpgt;
1385                 if (lun->unpacked_lun >= 256)
1386                         evt->event.lun[2] = lun->unpacked_lun >> 8 | 0x40 ;
1387                 evt->event.lun[3] = lun->unpacked_lun & 0xFF;
1388         }
1389
1390         llist_add(&evt->list, &vs->vs_event_list);
1391         vhost_work_queue(&vs->dev, &vs->vs_event_work);
1392 }
1393
1394 static void vhost_scsi_evt_handle_kick(struct vhost_work *work)
1395 {
1396         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1397                                                 poll.work);
1398         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1399
1400         mutex_lock(&vq->mutex);
1401         if (!vhost_vq_get_backend(vq))
1402                 goto out;
1403
1404         if (vs->vs_events_missed)
1405                 vhost_scsi_send_evt(vs, NULL, NULL, VIRTIO_SCSI_T_NO_EVENT, 0);
1406 out:
1407         mutex_unlock(&vq->mutex);
1408 }
1409
1410 static void vhost_scsi_handle_kick(struct vhost_work *work)
1411 {
1412         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1413                                                 poll.work);
1414         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1415
1416         vhost_scsi_handle_vq(vs, vq);
1417 }
1418
1419 /* Callers must hold dev mutex */
1420 static void vhost_scsi_flush(struct vhost_scsi *vs)
1421 {
1422         struct vhost_scsi_inflight *old_inflight[VHOST_SCSI_MAX_VQ];
1423         int i;
1424
1425         /* Init new inflight and remember the old inflight */
1426         vhost_scsi_init_inflight(vs, old_inflight);
1427
1428         /*
1429          * The inflight->kref was initialized to 1. We decrement it here to
1430          * indicate the start of the flush operation so that it will reach 0
1431          * when all the reqs are finished.
1432          */
1433         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1434                 kref_put(&old_inflight[i]->kref, vhost_scsi_done_inflight);
1435
1436         /* Flush both the vhost poll and vhost work */
1437         vhost_dev_flush(&vs->dev);
1438
1439         /* Wait for all reqs issued before the flush to be finished */
1440         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
1441                 wait_for_completion(&old_inflight[i]->comp);
1442 }
1443
1444 static void vhost_scsi_destroy_vq_cmds(struct vhost_virtqueue *vq)
1445 {
1446         struct vhost_scsi_virtqueue *svq = container_of(vq,
1447                                         struct vhost_scsi_virtqueue, vq);
1448         struct vhost_scsi_cmd *tv_cmd;
1449         unsigned int i;
1450
1451         if (!svq->scsi_cmds)
1452                 return;
1453
1454         for (i = 0; i < svq->max_cmds; i++) {
1455                 tv_cmd = &svq->scsi_cmds[i];
1456
1457                 kfree(tv_cmd->tvc_sgl);
1458                 kfree(tv_cmd->tvc_prot_sgl);
1459                 kfree(tv_cmd->tvc_upages);
1460         }
1461
1462         sbitmap_free(&svq->scsi_tags);
1463         kfree(svq->scsi_cmds);
1464         svq->scsi_cmds = NULL;
1465 }
1466
1467 static int vhost_scsi_setup_vq_cmds(struct vhost_virtqueue *vq, int max_cmds)
1468 {
1469         struct vhost_scsi_virtqueue *svq = container_of(vq,
1470                                         struct vhost_scsi_virtqueue, vq);
1471         struct vhost_scsi_cmd *tv_cmd;
1472         unsigned int i;
1473
1474         if (svq->scsi_cmds)
1475                 return 0;
1476
1477         if (sbitmap_init_node(&svq->scsi_tags, max_cmds, -1, GFP_KERNEL,
1478                               NUMA_NO_NODE, false, true))
1479                 return -ENOMEM;
1480         svq->max_cmds = max_cmds;
1481
1482         svq->scsi_cmds = kcalloc(max_cmds, sizeof(*tv_cmd), GFP_KERNEL);
1483         if (!svq->scsi_cmds) {
1484                 sbitmap_free(&svq->scsi_tags);
1485                 return -ENOMEM;
1486         }
1487
1488         for (i = 0; i < max_cmds; i++) {
1489                 tv_cmd = &svq->scsi_cmds[i];
1490
1491                 tv_cmd->tvc_sgl = kcalloc(VHOST_SCSI_PREALLOC_SGLS,
1492                                           sizeof(struct scatterlist),
1493                                           GFP_KERNEL);
1494                 if (!tv_cmd->tvc_sgl) {
1495                         pr_err("Unable to allocate tv_cmd->tvc_sgl\n");
1496                         goto out;
1497                 }
1498
1499                 tv_cmd->tvc_upages = kcalloc(VHOST_SCSI_PREALLOC_UPAGES,
1500                                              sizeof(struct page *),
1501                                              GFP_KERNEL);
1502                 if (!tv_cmd->tvc_upages) {
1503                         pr_err("Unable to allocate tv_cmd->tvc_upages\n");
1504                         goto out;
1505                 }
1506
1507                 tv_cmd->tvc_prot_sgl = kcalloc(VHOST_SCSI_PREALLOC_PROT_SGLS,
1508                                                sizeof(struct scatterlist),
1509                                                GFP_KERNEL);
1510                 if (!tv_cmd->tvc_prot_sgl) {
1511                         pr_err("Unable to allocate tv_cmd->tvc_prot_sgl\n");
1512                         goto out;
1513                 }
1514         }
1515         return 0;
1516 out:
1517         vhost_scsi_destroy_vq_cmds(vq);
1518         return -ENOMEM;
1519 }
1520
1521 /*
1522  * Called from vhost_scsi_ioctl() context to walk the list of available
1523  * vhost_scsi_tpg with an active struct vhost_scsi_nexus
1524  *
1525  *  The lock nesting rule is:
1526  *    vhost_scsi_mutex -> vs->dev.mutex -> tpg->tv_tpg_mutex -> vq->mutex
1527  */
1528 static int
1529 vhost_scsi_set_endpoint(struct vhost_scsi *vs,
1530                         struct vhost_scsi_target *t)
1531 {
1532         struct se_portal_group *se_tpg;
1533         struct vhost_scsi_tport *tv_tport;
1534         struct vhost_scsi_tpg *tpg;
1535         struct vhost_scsi_tpg **vs_tpg;
1536         struct vhost_virtqueue *vq;
1537         int index, ret, i, len;
1538         bool match = false;
1539
1540         mutex_lock(&vhost_scsi_mutex);
1541         mutex_lock(&vs->dev.mutex);
1542
1543         /* Verify that ring has been setup correctly. */
1544         for (index = 0; index < vs->dev.nvqs; ++index) {
1545                 /* Verify that ring has been setup correctly. */
1546                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1547                         ret = -EFAULT;
1548                         goto out;
1549                 }
1550         }
1551
1552         len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET;
1553         vs_tpg = kzalloc(len, GFP_KERNEL);
1554         if (!vs_tpg) {
1555                 ret = -ENOMEM;
1556                 goto out;
1557         }
1558         if (vs->vs_tpg)
1559                 memcpy(vs_tpg, vs->vs_tpg, len);
1560
1561         list_for_each_entry(tpg, &vhost_scsi_list, tv_tpg_list) {
1562                 mutex_lock(&tpg->tv_tpg_mutex);
1563                 if (!tpg->tpg_nexus) {
1564                         mutex_unlock(&tpg->tv_tpg_mutex);
1565                         continue;
1566                 }
1567                 if (tpg->tv_tpg_vhost_count != 0) {
1568                         mutex_unlock(&tpg->tv_tpg_mutex);
1569                         continue;
1570                 }
1571                 tv_tport = tpg->tport;
1572
1573                 if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1574                         if (vs->vs_tpg && vs->vs_tpg[tpg->tport_tpgt]) {
1575                                 mutex_unlock(&tpg->tv_tpg_mutex);
1576                                 ret = -EEXIST;
1577                                 goto undepend;
1578                         }
1579                         /*
1580                          * In order to ensure individual vhost-scsi configfs
1581                          * groups cannot be removed while in use by vhost ioctl,
1582                          * go ahead and take an explicit se_tpg->tpg_group.cg_item
1583                          * dependency now.
1584                          */
1585                         se_tpg = &tpg->se_tpg;
1586                         ret = target_depend_item(&se_tpg->tpg_group.cg_item);
1587                         if (ret) {
1588                                 pr_warn("target_depend_item() failed: %d\n", ret);
1589                                 mutex_unlock(&tpg->tv_tpg_mutex);
1590                                 goto undepend;
1591                         }
1592                         tpg->tv_tpg_vhost_count++;
1593                         tpg->vhost_scsi = vs;
1594                         vs_tpg[tpg->tport_tpgt] = tpg;
1595                         match = true;
1596                 }
1597                 mutex_unlock(&tpg->tv_tpg_mutex);
1598         }
1599
1600         if (match) {
1601                 memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
1602                        sizeof(vs->vs_vhost_wwpn));
1603
1604                 for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++) {
1605                         vq = &vs->vqs[i].vq;
1606                         if (!vhost_vq_is_setup(vq))
1607                                 continue;
1608
1609                         ret = vhost_scsi_setup_vq_cmds(vq, vq->num);
1610                         if (ret)
1611                                 goto destroy_vq_cmds;
1612                 }
1613
1614                 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1615                         vq = &vs->vqs[i].vq;
1616                         mutex_lock(&vq->mutex);
1617                         vhost_vq_set_backend(vq, vs_tpg);
1618                         vhost_vq_init_access(vq);
1619                         mutex_unlock(&vq->mutex);
1620                 }
1621                 ret = 0;
1622         } else {
1623                 ret = -EEXIST;
1624         }
1625
1626         /*
1627          * Act as synchronize_rcu to make sure access to
1628          * old vs->vs_tpg is finished.
1629          */
1630         vhost_scsi_flush(vs);
1631         kfree(vs->vs_tpg);
1632         vs->vs_tpg = vs_tpg;
1633         goto out;
1634
1635 destroy_vq_cmds:
1636         for (i--; i >= VHOST_SCSI_VQ_IO; i--) {
1637                 if (!vhost_vq_get_backend(&vs->vqs[i].vq))
1638                         vhost_scsi_destroy_vq_cmds(&vs->vqs[i].vq);
1639         }
1640 undepend:
1641         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1642                 tpg = vs_tpg[i];
1643                 if (tpg) {
1644                         tpg->tv_tpg_vhost_count--;
1645                         target_undepend_item(&tpg->se_tpg.tpg_group.cg_item);
1646                 }
1647         }
1648         kfree(vs_tpg);
1649 out:
1650         mutex_unlock(&vs->dev.mutex);
1651         mutex_unlock(&vhost_scsi_mutex);
1652         return ret;
1653 }
1654
1655 static int
1656 vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
1657                           struct vhost_scsi_target *t)
1658 {
1659         struct se_portal_group *se_tpg;
1660         struct vhost_scsi_tport *tv_tport;
1661         struct vhost_scsi_tpg *tpg;
1662         struct vhost_virtqueue *vq;
1663         bool match = false;
1664         int index, ret, i;
1665         u8 target;
1666
1667         mutex_lock(&vhost_scsi_mutex);
1668         mutex_lock(&vs->dev.mutex);
1669         /* Verify that ring has been setup correctly. */
1670         for (index = 0; index < vs->dev.nvqs; ++index) {
1671                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1672                         ret = -EFAULT;
1673                         goto err_dev;
1674                 }
1675         }
1676
1677         if (!vs->vs_tpg) {
1678                 ret = 0;
1679                 goto err_dev;
1680         }
1681
1682         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1683                 target = i;
1684                 tpg = vs->vs_tpg[target];
1685                 if (!tpg)
1686                         continue;
1687
1688                 mutex_lock(&tpg->tv_tpg_mutex);
1689                 tv_tport = tpg->tport;
1690                 if (!tv_tport) {
1691                         ret = -ENODEV;
1692                         goto err_tpg;
1693                 }
1694
1695                 if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1696                         pr_warn("tv_tport->tport_name: %s, tpg->tport_tpgt: %hu"
1697                                 " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
1698                                 tv_tport->tport_name, tpg->tport_tpgt,
1699                                 t->vhost_wwpn, t->vhost_tpgt);
1700                         ret = -EINVAL;
1701                         goto err_tpg;
1702                 }
1703                 tpg->tv_tpg_vhost_count--;
1704                 tpg->vhost_scsi = NULL;
1705                 vs->vs_tpg[target] = NULL;
1706                 match = true;
1707                 mutex_unlock(&tpg->tv_tpg_mutex);
1708                 /*
1709                  * Release se_tpg->tpg_group.cg_item configfs dependency now
1710                  * to allow vhost-scsi WWPN se_tpg->tpg_group shutdown to occur.
1711                  */
1712                 se_tpg = &tpg->se_tpg;
1713                 target_undepend_item(&se_tpg->tpg_group.cg_item);
1714         }
1715         if (match) {
1716                 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1717                         vq = &vs->vqs[i].vq;
1718                         mutex_lock(&vq->mutex);
1719                         vhost_vq_set_backend(vq, NULL);
1720                         mutex_unlock(&vq->mutex);
1721                 }
1722                 /* Make sure cmds are not running before tearing them down. */
1723                 vhost_scsi_flush(vs);
1724
1725                 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1726                         vq = &vs->vqs[i].vq;
1727                         vhost_scsi_destroy_vq_cmds(vq);
1728                 }
1729         }
1730         /*
1731          * Act as synchronize_rcu to make sure access to
1732          * old vs->vs_tpg is finished.
1733          */
1734         vhost_scsi_flush(vs);
1735         kfree(vs->vs_tpg);
1736         vs->vs_tpg = NULL;
1737         WARN_ON(vs->vs_events_nr);
1738         mutex_unlock(&vs->dev.mutex);
1739         mutex_unlock(&vhost_scsi_mutex);
1740         return 0;
1741
1742 err_tpg:
1743         mutex_unlock(&tpg->tv_tpg_mutex);
1744 err_dev:
1745         mutex_unlock(&vs->dev.mutex);
1746         mutex_unlock(&vhost_scsi_mutex);
1747         return ret;
1748 }
1749
1750 static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features)
1751 {
1752         struct vhost_virtqueue *vq;
1753         int i;
1754
1755         if (features & ~VHOST_SCSI_FEATURES)
1756                 return -EOPNOTSUPP;
1757
1758         mutex_lock(&vs->dev.mutex);
1759         if ((features & (1 << VHOST_F_LOG_ALL)) &&
1760             !vhost_log_access_ok(&vs->dev)) {
1761                 mutex_unlock(&vs->dev.mutex);
1762                 return -EFAULT;
1763         }
1764
1765         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
1766                 vq = &vs->vqs[i].vq;
1767                 mutex_lock(&vq->mutex);
1768                 vq->acked_features = features;
1769                 mutex_unlock(&vq->mutex);
1770         }
1771         mutex_unlock(&vs->dev.mutex);
1772         return 0;
1773 }
1774
1775 static int vhost_scsi_open(struct inode *inode, struct file *f)
1776 {
1777         struct vhost_scsi *vs;
1778         struct vhost_virtqueue **vqs;
1779         int r = -ENOMEM, i;
1780
1781         vs = kvzalloc(sizeof(*vs), GFP_KERNEL);
1782         if (!vs)
1783                 goto err_vs;
1784
1785         vqs = kmalloc_array(VHOST_SCSI_MAX_VQ, sizeof(*vqs), GFP_KERNEL);
1786         if (!vqs)
1787                 goto err_vqs;
1788
1789         vhost_work_init(&vs->vs_completion_work, vhost_scsi_complete_cmd_work);
1790         vhost_work_init(&vs->vs_event_work, vhost_scsi_evt_work);
1791
1792         vs->vs_events_nr = 0;
1793         vs->vs_events_missed = false;
1794
1795         vqs[VHOST_SCSI_VQ_CTL] = &vs->vqs[VHOST_SCSI_VQ_CTL].vq;
1796         vqs[VHOST_SCSI_VQ_EVT] = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1797         vs->vqs[VHOST_SCSI_VQ_CTL].vq.handle_kick = vhost_scsi_ctl_handle_kick;
1798         vs->vqs[VHOST_SCSI_VQ_EVT].vq.handle_kick = vhost_scsi_evt_handle_kick;
1799         for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++) {
1800                 vqs[i] = &vs->vqs[i].vq;
1801                 vs->vqs[i].vq.handle_kick = vhost_scsi_handle_kick;
1802         }
1803         vhost_dev_init(&vs->dev, vqs, VHOST_SCSI_MAX_VQ, UIO_MAXIOV,
1804                        VHOST_SCSI_WEIGHT, 0, true, NULL);
1805
1806         vhost_scsi_init_inflight(vs, NULL);
1807
1808         f->private_data = vs;
1809         return 0;
1810
1811 err_vqs:
1812         kvfree(vs);
1813 err_vs:
1814         return r;
1815 }
1816
1817 static int vhost_scsi_release(struct inode *inode, struct file *f)
1818 {
1819         struct vhost_scsi *vs = f->private_data;
1820         struct vhost_scsi_target t;
1821
1822         mutex_lock(&vs->dev.mutex);
1823         memcpy(t.vhost_wwpn, vs->vs_vhost_wwpn, sizeof(t.vhost_wwpn));
1824         mutex_unlock(&vs->dev.mutex);
1825         vhost_scsi_clear_endpoint(vs, &t);
1826         vhost_dev_stop(&vs->dev);
1827         vhost_dev_cleanup(&vs->dev);
1828         kfree(vs->dev.vqs);
1829         kvfree(vs);
1830         return 0;
1831 }
1832
1833 static long
1834 vhost_scsi_ioctl(struct file *f,
1835                  unsigned int ioctl,
1836                  unsigned long arg)
1837 {
1838         struct vhost_scsi *vs = f->private_data;
1839         struct vhost_scsi_target backend;
1840         void __user *argp = (void __user *)arg;
1841         u64 __user *featurep = argp;
1842         u32 __user *eventsp = argp;
1843         u32 events_missed;
1844         u64 features;
1845         int r, abi_version = VHOST_SCSI_ABI_VERSION;
1846         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1847
1848         switch (ioctl) {
1849         case VHOST_SCSI_SET_ENDPOINT:
1850                 if (copy_from_user(&backend, argp, sizeof backend))
1851                         return -EFAULT;
1852                 if (backend.reserved != 0)
1853                         return -EOPNOTSUPP;
1854
1855                 return vhost_scsi_set_endpoint(vs, &backend);
1856         case VHOST_SCSI_CLEAR_ENDPOINT:
1857                 if (copy_from_user(&backend, argp, sizeof backend))
1858                         return -EFAULT;
1859                 if (backend.reserved != 0)
1860                         return -EOPNOTSUPP;
1861
1862                 return vhost_scsi_clear_endpoint(vs, &backend);
1863         case VHOST_SCSI_GET_ABI_VERSION:
1864                 if (copy_to_user(argp, &abi_version, sizeof abi_version))
1865                         return -EFAULT;
1866                 return 0;
1867         case VHOST_SCSI_SET_EVENTS_MISSED:
1868                 if (get_user(events_missed, eventsp))
1869                         return -EFAULT;
1870                 mutex_lock(&vq->mutex);
1871                 vs->vs_events_missed = events_missed;
1872                 mutex_unlock(&vq->mutex);
1873                 return 0;
1874         case VHOST_SCSI_GET_EVENTS_MISSED:
1875                 mutex_lock(&vq->mutex);
1876                 events_missed = vs->vs_events_missed;
1877                 mutex_unlock(&vq->mutex);
1878                 if (put_user(events_missed, eventsp))
1879                         return -EFAULT;
1880                 return 0;
1881         case VHOST_GET_FEATURES:
1882                 features = VHOST_SCSI_FEATURES;
1883                 if (copy_to_user(featurep, &features, sizeof features))
1884                         return -EFAULT;
1885                 return 0;
1886         case VHOST_SET_FEATURES:
1887                 if (copy_from_user(&features, featurep, sizeof features))
1888                         return -EFAULT;
1889                 return vhost_scsi_set_features(vs, features);
1890         default:
1891                 mutex_lock(&vs->dev.mutex);
1892                 r = vhost_dev_ioctl(&vs->dev, ioctl, argp);
1893                 /* TODO: flush backend after dev ioctl. */
1894                 if (r == -ENOIOCTLCMD)
1895                         r = vhost_vring_ioctl(&vs->dev, ioctl, argp);
1896                 mutex_unlock(&vs->dev.mutex);
1897                 return r;
1898         }
1899 }
1900
1901 static const struct file_operations vhost_scsi_fops = {
1902         .owner          = THIS_MODULE,
1903         .release        = vhost_scsi_release,
1904         .unlocked_ioctl = vhost_scsi_ioctl,
1905         .compat_ioctl   = compat_ptr_ioctl,
1906         .open           = vhost_scsi_open,
1907         .llseek         = noop_llseek,
1908 };
1909
1910 static struct miscdevice vhost_scsi_misc = {
1911         MISC_DYNAMIC_MINOR,
1912         "vhost-scsi",
1913         &vhost_scsi_fops,
1914 };
1915
1916 static int __init vhost_scsi_register(void)
1917 {
1918         return misc_register(&vhost_scsi_misc);
1919 }
1920
1921 static void vhost_scsi_deregister(void)
1922 {
1923         misc_deregister(&vhost_scsi_misc);
1924 }
1925
1926 static char *vhost_scsi_dump_proto_id(struct vhost_scsi_tport *tport)
1927 {
1928         switch (tport->tport_proto_id) {
1929         case SCSI_PROTOCOL_SAS:
1930                 return "SAS";
1931         case SCSI_PROTOCOL_FCP:
1932                 return "FCP";
1933         case SCSI_PROTOCOL_ISCSI:
1934                 return "iSCSI";
1935         default:
1936                 break;
1937         }
1938
1939         return "Unknown";
1940 }
1941
1942 static void
1943 vhost_scsi_do_plug(struct vhost_scsi_tpg *tpg,
1944                   struct se_lun *lun, bool plug)
1945 {
1946
1947         struct vhost_scsi *vs = tpg->vhost_scsi;
1948         struct vhost_virtqueue *vq;
1949         u32 reason;
1950
1951         if (!vs)
1952                 return;
1953
1954         mutex_lock(&vs->dev.mutex);
1955
1956         if (plug)
1957                 reason = VIRTIO_SCSI_EVT_RESET_RESCAN;
1958         else
1959                 reason = VIRTIO_SCSI_EVT_RESET_REMOVED;
1960
1961         vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1962         mutex_lock(&vq->mutex);
1963         if (vhost_has_feature(vq, VIRTIO_SCSI_F_HOTPLUG))
1964                 vhost_scsi_send_evt(vs, tpg, lun,
1965                                    VIRTIO_SCSI_T_TRANSPORT_RESET, reason);
1966         mutex_unlock(&vq->mutex);
1967         mutex_unlock(&vs->dev.mutex);
1968 }
1969
1970 static void vhost_scsi_hotplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
1971 {
1972         vhost_scsi_do_plug(tpg, lun, true);
1973 }
1974
1975 static void vhost_scsi_hotunplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
1976 {
1977         vhost_scsi_do_plug(tpg, lun, false);
1978 }
1979
1980 static int vhost_scsi_port_link(struct se_portal_group *se_tpg,
1981                                struct se_lun *lun)
1982 {
1983         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
1984                                 struct vhost_scsi_tpg, se_tpg);
1985         struct vhost_scsi_tmf *tmf;
1986
1987         tmf = kzalloc(sizeof(*tmf), GFP_KERNEL);
1988         if (!tmf)
1989                 return -ENOMEM;
1990         INIT_LIST_HEAD(&tmf->queue_entry);
1991         vhost_work_init(&tmf->vwork, vhost_scsi_tmf_resp_work);
1992
1993         mutex_lock(&vhost_scsi_mutex);
1994
1995         mutex_lock(&tpg->tv_tpg_mutex);
1996         tpg->tv_tpg_port_count++;
1997         list_add_tail(&tmf->queue_entry, &tpg->tmf_queue);
1998         mutex_unlock(&tpg->tv_tpg_mutex);
1999
2000         vhost_scsi_hotplug(tpg, lun);
2001
2002         mutex_unlock(&vhost_scsi_mutex);
2003
2004         return 0;
2005 }
2006
2007 static void vhost_scsi_port_unlink(struct se_portal_group *se_tpg,
2008                                   struct se_lun *lun)
2009 {
2010         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2011                                 struct vhost_scsi_tpg, se_tpg);
2012         struct vhost_scsi_tmf *tmf;
2013
2014         mutex_lock(&vhost_scsi_mutex);
2015
2016         mutex_lock(&tpg->tv_tpg_mutex);
2017         tpg->tv_tpg_port_count--;
2018         tmf = list_first_entry(&tpg->tmf_queue, struct vhost_scsi_tmf,
2019                                queue_entry);
2020         list_del(&tmf->queue_entry);
2021         kfree(tmf);
2022         mutex_unlock(&tpg->tv_tpg_mutex);
2023
2024         vhost_scsi_hotunplug(tpg, lun);
2025
2026         mutex_unlock(&vhost_scsi_mutex);
2027 }
2028
2029 static ssize_t vhost_scsi_tpg_attrib_fabric_prot_type_store(
2030                 struct config_item *item, const char *page, size_t count)
2031 {
2032         struct se_portal_group *se_tpg = attrib_to_tpg(item);
2033         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2034                                 struct vhost_scsi_tpg, se_tpg);
2035         unsigned long val;
2036         int ret = kstrtoul(page, 0, &val);
2037
2038         if (ret) {
2039                 pr_err("kstrtoul() returned %d for fabric_prot_type\n", ret);
2040                 return ret;
2041         }
2042         if (val != 0 && val != 1 && val != 3) {
2043                 pr_err("Invalid vhost_scsi fabric_prot_type: %lu\n", val);
2044                 return -EINVAL;
2045         }
2046         tpg->tv_fabric_prot_type = val;
2047
2048         return count;
2049 }
2050
2051 static ssize_t vhost_scsi_tpg_attrib_fabric_prot_type_show(
2052                 struct config_item *item, char *page)
2053 {
2054         struct se_portal_group *se_tpg = attrib_to_tpg(item);
2055         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2056                                 struct vhost_scsi_tpg, se_tpg);
2057
2058         return sprintf(page, "%d\n", tpg->tv_fabric_prot_type);
2059 }
2060
2061 CONFIGFS_ATTR(vhost_scsi_tpg_attrib_, fabric_prot_type);
2062
2063 static struct configfs_attribute *vhost_scsi_tpg_attrib_attrs[] = {
2064         &vhost_scsi_tpg_attrib_attr_fabric_prot_type,
2065         NULL,
2066 };
2067
2068 static int vhost_scsi_make_nexus(struct vhost_scsi_tpg *tpg,
2069                                 const char *name)
2070 {
2071         struct vhost_scsi_nexus *tv_nexus;
2072
2073         mutex_lock(&tpg->tv_tpg_mutex);
2074         if (tpg->tpg_nexus) {
2075                 mutex_unlock(&tpg->tv_tpg_mutex);
2076                 pr_debug("tpg->tpg_nexus already exists\n");
2077                 return -EEXIST;
2078         }
2079
2080         tv_nexus = kzalloc(sizeof(*tv_nexus), GFP_KERNEL);
2081         if (!tv_nexus) {
2082                 mutex_unlock(&tpg->tv_tpg_mutex);
2083                 pr_err("Unable to allocate struct vhost_scsi_nexus\n");
2084                 return -ENOMEM;
2085         }
2086         /*
2087          * Since we are running in 'demo mode' this call with generate a
2088          * struct se_node_acl for the vhost_scsi struct se_portal_group with
2089          * the SCSI Initiator port name of the passed configfs group 'name'.
2090          */
2091         tv_nexus->tvn_se_sess = target_setup_session(&tpg->se_tpg, 0, 0,
2092                                         TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS,
2093                                         (unsigned char *)name, tv_nexus, NULL);
2094         if (IS_ERR(tv_nexus->tvn_se_sess)) {
2095                 mutex_unlock(&tpg->tv_tpg_mutex);
2096                 kfree(tv_nexus);
2097                 return -ENOMEM;
2098         }
2099         tpg->tpg_nexus = tv_nexus;
2100
2101         mutex_unlock(&tpg->tv_tpg_mutex);
2102         return 0;
2103 }
2104
2105 static int vhost_scsi_drop_nexus(struct vhost_scsi_tpg *tpg)
2106 {
2107         struct se_session *se_sess;
2108         struct vhost_scsi_nexus *tv_nexus;
2109
2110         mutex_lock(&tpg->tv_tpg_mutex);
2111         tv_nexus = tpg->tpg_nexus;
2112         if (!tv_nexus) {
2113                 mutex_unlock(&tpg->tv_tpg_mutex);
2114                 return -ENODEV;
2115         }
2116
2117         se_sess = tv_nexus->tvn_se_sess;
2118         if (!se_sess) {
2119                 mutex_unlock(&tpg->tv_tpg_mutex);
2120                 return -ENODEV;
2121         }
2122
2123         if (tpg->tv_tpg_port_count != 0) {
2124                 mutex_unlock(&tpg->tv_tpg_mutex);
2125                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
2126                         " active TPG port count: %d\n",
2127                         tpg->tv_tpg_port_count);
2128                 return -EBUSY;
2129         }
2130
2131         if (tpg->tv_tpg_vhost_count != 0) {
2132                 mutex_unlock(&tpg->tv_tpg_mutex);
2133                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
2134                         " active TPG vhost count: %d\n",
2135                         tpg->tv_tpg_vhost_count);
2136                 return -EBUSY;
2137         }
2138
2139         pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated"
2140                 " %s Initiator Port: %s\n", vhost_scsi_dump_proto_id(tpg->tport),
2141                 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
2142
2143         /*
2144          * Release the SCSI I_T Nexus to the emulated vhost Target Port
2145          */
2146         target_remove_session(se_sess);
2147         tpg->tpg_nexus = NULL;
2148         mutex_unlock(&tpg->tv_tpg_mutex);
2149
2150         kfree(tv_nexus);
2151         return 0;
2152 }
2153
2154 static ssize_t vhost_scsi_tpg_nexus_show(struct config_item *item, char *page)
2155 {
2156         struct se_portal_group *se_tpg = to_tpg(item);
2157         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2158                                 struct vhost_scsi_tpg, se_tpg);
2159         struct vhost_scsi_nexus *tv_nexus;
2160         ssize_t ret;
2161
2162         mutex_lock(&tpg->tv_tpg_mutex);
2163         tv_nexus = tpg->tpg_nexus;
2164         if (!tv_nexus) {
2165                 mutex_unlock(&tpg->tv_tpg_mutex);
2166                 return -ENODEV;
2167         }
2168         ret = snprintf(page, PAGE_SIZE, "%s\n",
2169                         tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
2170         mutex_unlock(&tpg->tv_tpg_mutex);
2171
2172         return ret;
2173 }
2174
2175 static ssize_t vhost_scsi_tpg_nexus_store(struct config_item *item,
2176                 const char *page, size_t count)
2177 {
2178         struct se_portal_group *se_tpg = to_tpg(item);
2179         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2180                                 struct vhost_scsi_tpg, se_tpg);
2181         struct vhost_scsi_tport *tport_wwn = tpg->tport;
2182         unsigned char i_port[VHOST_SCSI_NAMELEN], *ptr, *port_ptr;
2183         int ret;
2184         /*
2185          * Shutdown the active I_T nexus if 'NULL' is passed..
2186          */
2187         if (!strncmp(page, "NULL", 4)) {
2188                 ret = vhost_scsi_drop_nexus(tpg);
2189                 return (!ret) ? count : ret;
2190         }
2191         /*
2192          * Otherwise make sure the passed virtual Initiator port WWN matches
2193          * the fabric protocol_id set in vhost_scsi_make_tport(), and call
2194          * vhost_scsi_make_nexus().
2195          */
2196         if (strlen(page) >= VHOST_SCSI_NAMELEN) {
2197                 pr_err("Emulated NAA Sas Address: %s, exceeds"
2198                                 " max: %d\n", page, VHOST_SCSI_NAMELEN);
2199                 return -EINVAL;
2200         }
2201         snprintf(&i_port[0], VHOST_SCSI_NAMELEN, "%s", page);
2202
2203         ptr = strstr(i_port, "naa.");
2204         if (ptr) {
2205                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
2206                         pr_err("Passed SAS Initiator Port %s does not"
2207                                 " match target port protoid: %s\n", i_port,
2208                                 vhost_scsi_dump_proto_id(tport_wwn));
2209                         return -EINVAL;
2210                 }
2211                 port_ptr = &i_port[0];
2212                 goto check_newline;
2213         }
2214         ptr = strstr(i_port, "fc.");
2215         if (ptr) {
2216                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
2217                         pr_err("Passed FCP Initiator Port %s does not"
2218                                 " match target port protoid: %s\n", i_port,
2219                                 vhost_scsi_dump_proto_id(tport_wwn));
2220                         return -EINVAL;
2221                 }
2222                 port_ptr = &i_port[3]; /* Skip over "fc." */
2223                 goto check_newline;
2224         }
2225         ptr = strstr(i_port, "iqn.");
2226         if (ptr) {
2227                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
2228                         pr_err("Passed iSCSI Initiator Port %s does not"
2229                                 " match target port protoid: %s\n", i_port,
2230                                 vhost_scsi_dump_proto_id(tport_wwn));
2231                         return -EINVAL;
2232                 }
2233                 port_ptr = &i_port[0];
2234                 goto check_newline;
2235         }
2236         pr_err("Unable to locate prefix for emulated Initiator Port:"
2237                         " %s\n", i_port);
2238         return -EINVAL;
2239         /*
2240          * Clear any trailing newline for the NAA WWN
2241          */
2242 check_newline:
2243         if (i_port[strlen(i_port)-1] == '\n')
2244                 i_port[strlen(i_port)-1] = '\0';
2245
2246         ret = vhost_scsi_make_nexus(tpg, port_ptr);
2247         if (ret < 0)
2248                 return ret;
2249
2250         return count;
2251 }
2252
2253 CONFIGFS_ATTR(vhost_scsi_tpg_, nexus);
2254
2255 static struct configfs_attribute *vhost_scsi_tpg_attrs[] = {
2256         &vhost_scsi_tpg_attr_nexus,
2257         NULL,
2258 };
2259
2260 static struct se_portal_group *
2261 vhost_scsi_make_tpg(struct se_wwn *wwn, const char *name)
2262 {
2263         struct vhost_scsi_tport *tport = container_of(wwn,
2264                         struct vhost_scsi_tport, tport_wwn);
2265
2266         struct vhost_scsi_tpg *tpg;
2267         u16 tpgt;
2268         int ret;
2269
2270         if (strstr(name, "tpgt_") != name)
2271                 return ERR_PTR(-EINVAL);
2272         if (kstrtou16(name + 5, 10, &tpgt) || tpgt >= VHOST_SCSI_MAX_TARGET)
2273                 return ERR_PTR(-EINVAL);
2274
2275         tpg = kzalloc(sizeof(*tpg), GFP_KERNEL);
2276         if (!tpg) {
2277                 pr_err("Unable to allocate struct vhost_scsi_tpg");
2278                 return ERR_PTR(-ENOMEM);
2279         }
2280         mutex_init(&tpg->tv_tpg_mutex);
2281         INIT_LIST_HEAD(&tpg->tv_tpg_list);
2282         INIT_LIST_HEAD(&tpg->tmf_queue);
2283         tpg->tport = tport;
2284         tpg->tport_tpgt = tpgt;
2285
2286         ret = core_tpg_register(wwn, &tpg->se_tpg, tport->tport_proto_id);
2287         if (ret < 0) {
2288                 kfree(tpg);
2289                 return NULL;
2290         }
2291         mutex_lock(&vhost_scsi_mutex);
2292         list_add_tail(&tpg->tv_tpg_list, &vhost_scsi_list);
2293         mutex_unlock(&vhost_scsi_mutex);
2294
2295         return &tpg->se_tpg;
2296 }
2297
2298 static void vhost_scsi_drop_tpg(struct se_portal_group *se_tpg)
2299 {
2300         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2301                                 struct vhost_scsi_tpg, se_tpg);
2302
2303         mutex_lock(&vhost_scsi_mutex);
2304         list_del(&tpg->tv_tpg_list);
2305         mutex_unlock(&vhost_scsi_mutex);
2306         /*
2307          * Release the virtual I_T Nexus for this vhost TPG
2308          */
2309         vhost_scsi_drop_nexus(tpg);
2310         /*
2311          * Deregister the se_tpg from TCM..
2312          */
2313         core_tpg_deregister(se_tpg);
2314         kfree(tpg);
2315 }
2316
2317 static struct se_wwn *
2318 vhost_scsi_make_tport(struct target_fabric_configfs *tf,
2319                      struct config_group *group,
2320                      const char *name)
2321 {
2322         struct vhost_scsi_tport *tport;
2323         char *ptr;
2324         u64 wwpn = 0;
2325         int off = 0;
2326
2327         /* if (vhost_scsi_parse_wwn(name, &wwpn, 1) < 0)
2328                 return ERR_PTR(-EINVAL); */
2329
2330         tport = kzalloc(sizeof(*tport), GFP_KERNEL);
2331         if (!tport) {
2332                 pr_err("Unable to allocate struct vhost_scsi_tport");
2333                 return ERR_PTR(-ENOMEM);
2334         }
2335         tport->tport_wwpn = wwpn;
2336         /*
2337          * Determine the emulated Protocol Identifier and Target Port Name
2338          * based on the incoming configfs directory name.
2339          */
2340         ptr = strstr(name, "naa.");
2341         if (ptr) {
2342                 tport->tport_proto_id = SCSI_PROTOCOL_SAS;
2343                 goto check_len;
2344         }
2345         ptr = strstr(name, "fc.");
2346         if (ptr) {
2347                 tport->tport_proto_id = SCSI_PROTOCOL_FCP;
2348                 off = 3; /* Skip over "fc." */
2349                 goto check_len;
2350         }
2351         ptr = strstr(name, "iqn.");
2352         if (ptr) {
2353                 tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
2354                 goto check_len;
2355         }
2356
2357         pr_err("Unable to locate prefix for emulated Target Port:"
2358                         " %s\n", name);
2359         kfree(tport);
2360         return ERR_PTR(-EINVAL);
2361
2362 check_len:
2363         if (strlen(name) >= VHOST_SCSI_NAMELEN) {
2364                 pr_err("Emulated %s Address: %s, exceeds"
2365                         " max: %d\n", name, vhost_scsi_dump_proto_id(tport),
2366                         VHOST_SCSI_NAMELEN);
2367                 kfree(tport);
2368                 return ERR_PTR(-EINVAL);
2369         }
2370         snprintf(&tport->tport_name[0], VHOST_SCSI_NAMELEN, "%s", &name[off]);
2371
2372         pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target"
2373                 " %s Address: %s\n", vhost_scsi_dump_proto_id(tport), name);
2374
2375         return &tport->tport_wwn;
2376 }
2377
2378 static void vhost_scsi_drop_tport(struct se_wwn *wwn)
2379 {
2380         struct vhost_scsi_tport *tport = container_of(wwn,
2381                                 struct vhost_scsi_tport, tport_wwn);
2382
2383         pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target"
2384                 " %s Address: %s\n", vhost_scsi_dump_proto_id(tport),
2385                 tport->tport_name);
2386
2387         kfree(tport);
2388 }
2389
2390 static ssize_t
2391 vhost_scsi_wwn_version_show(struct config_item *item, char *page)
2392 {
2393         return sprintf(page, "TCM_VHOST fabric module %s on %s/%s"
2394                 "on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
2395                 utsname()->machine);
2396 }
2397
2398 CONFIGFS_ATTR_RO(vhost_scsi_wwn_, version);
2399
2400 static struct configfs_attribute *vhost_scsi_wwn_attrs[] = {
2401         &vhost_scsi_wwn_attr_version,
2402         NULL,
2403 };
2404
2405 static const struct target_core_fabric_ops vhost_scsi_ops = {
2406         .module                         = THIS_MODULE,
2407         .fabric_name                    = "vhost",
2408         .max_data_sg_nents              = VHOST_SCSI_PREALLOC_SGLS,
2409         .tpg_get_wwn                    = vhost_scsi_get_fabric_wwn,
2410         .tpg_get_tag                    = vhost_scsi_get_tpgt,
2411         .tpg_check_demo_mode            = vhost_scsi_check_true,
2412         .tpg_check_demo_mode_cache      = vhost_scsi_check_true,
2413         .tpg_check_demo_mode_write_protect = vhost_scsi_check_false,
2414         .tpg_check_prod_mode_write_protect = vhost_scsi_check_false,
2415         .tpg_check_prot_fabric_only     = vhost_scsi_check_prot_fabric_only,
2416         .tpg_get_inst_index             = vhost_scsi_tpg_get_inst_index,
2417         .release_cmd                    = vhost_scsi_release_cmd,
2418         .check_stop_free                = vhost_scsi_check_stop_free,
2419         .sess_get_index                 = vhost_scsi_sess_get_index,
2420         .sess_get_initiator_sid         = NULL,
2421         .write_pending                  = vhost_scsi_write_pending,
2422         .set_default_node_attributes    = vhost_scsi_set_default_node_attrs,
2423         .get_cmd_state                  = vhost_scsi_get_cmd_state,
2424         .queue_data_in                  = vhost_scsi_queue_data_in,
2425         .queue_status                   = vhost_scsi_queue_status,
2426         .queue_tm_rsp                   = vhost_scsi_queue_tm_rsp,
2427         .aborted_task                   = vhost_scsi_aborted_task,
2428         /*
2429          * Setup callers for generic logic in target_core_fabric_configfs.c
2430          */
2431         .fabric_make_wwn                = vhost_scsi_make_tport,
2432         .fabric_drop_wwn                = vhost_scsi_drop_tport,
2433         .fabric_make_tpg                = vhost_scsi_make_tpg,
2434         .fabric_drop_tpg                = vhost_scsi_drop_tpg,
2435         .fabric_post_link               = vhost_scsi_port_link,
2436         .fabric_pre_unlink              = vhost_scsi_port_unlink,
2437
2438         .tfc_wwn_attrs                  = vhost_scsi_wwn_attrs,
2439         .tfc_tpg_base_attrs             = vhost_scsi_tpg_attrs,
2440         .tfc_tpg_attrib_attrs           = vhost_scsi_tpg_attrib_attrs,
2441 };
2442
2443 static int __init vhost_scsi_init(void)
2444 {
2445         int ret = -ENOMEM;
2446
2447         pr_debug("TCM_VHOST fabric module %s on %s/%s"
2448                 " on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
2449                 utsname()->machine);
2450
2451         ret = vhost_scsi_register();
2452         if (ret < 0)
2453                 goto out;
2454
2455         ret = target_register_template(&vhost_scsi_ops);
2456         if (ret < 0)
2457                 goto out_vhost_scsi_deregister;
2458
2459         return 0;
2460
2461 out_vhost_scsi_deregister:
2462         vhost_scsi_deregister();
2463 out:
2464         return ret;
2465 };
2466
2467 static void vhost_scsi_exit(void)
2468 {
2469         target_unregister_template(&vhost_scsi_ops);
2470         vhost_scsi_deregister();
2471 };
2472
2473 MODULE_DESCRIPTION("VHOST_SCSI series fabric driver");
2474 MODULE_ALIAS("tcm_vhost");
2475 MODULE_LICENSE("GPL");
2476 module_init(vhost_scsi_init);
2477 module_exit(vhost_scsi_exit);