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_IO_VQ    1024
 163 #define VHOST_SCSI_MAX_EVENT    128
 164
 165 static unsigned vhost_scsi_max_io_vqs = 128;
 166 module_param_named(max_io_vqs, vhost_scsi_max_io_vqs, uint, 0644);
 167 MODULE_PARM_DESC(max_io_vqs, "Set the max number of IO virtqueues a vhost scsi device can support. The default is 128. The max is 1024.");
 168
 169 struct vhost_scsi_virtqueue {
 170         struct vhost_virtqueue vq;
 171         /*
 172          * Reference counting for inflight reqs, used for flush operation. At
 173          * each time, one reference tracks new commands submitted, while we
 174          * wait for another one to reach 0.
 175          */
 176         struct vhost_scsi_inflight inflights[2];
 177         /*
 178          * Indicate current inflight in use, protected by vq->mutex.
 179          * Writers must also take dev mutex and flush under it.
 180          */
 181         int inflight_idx;
 182         struct vhost_scsi_cmd *scsi_cmds;
 183         struct sbitmap scsi_tags;
 184         int max_cmds;
 185 };
 186
 187 struct vhost_scsi {
 188         /* Protected by vhost_scsi->dev.mutex */
 189         struct vhost_scsi_tpg **vs_tpg;
 190         char vs_vhost_wwpn[TRANSPORT_IQN_LEN];
 191
 192         struct vhost_dev dev;
 193         struct vhost_scsi_virtqueue *vqs;
 194         unsigned long *compl_bitmap;
 195         struct vhost_scsi_inflight **old_inflight;
 196
 197         struct vhost_work vs_completion_work; /* cmd completion work item */
 198         struct llist_head vs_completion_list; /* cmd completion queue */
 199
 200         struct vhost_work vs_event_work; /* evt injection work item */
 201         struct llist_head vs_event_list; /* evt injection queue */
 202
 203         bool vs_events_missed; /* any missed events, protected by vq->mutex */
 204         int vs_events_nr; /* num of pending events, protected by vq->mutex */
 205 };
 206
 207 struct vhost_scsi_tmf {
 208         struct vhost_work vwork;
 209         struct vhost_scsi_tpg *tpg;
 210         struct vhost_scsi *vhost;
 211         struct vhost_scsi_virtqueue *svq;
 212         struct list_head queue_entry;
 213
 214         struct se_cmd se_cmd;
 215         u8 scsi_resp;
 216         struct vhost_scsi_inflight *inflight;
 217         struct iovec resp_iov;
 218         int in_iovs;
 219         int vq_desc;
 220 };
 221
 222 /*
 223  * Context for processing request and control queue operations.
 224  */
 225 struct vhost_scsi_ctx {
 226         int head;
 227         unsigned int out, in;
 228         size_t req_size, rsp_size;
 229         size_t out_size, in_size;
 230         u8 *target, *lunp;
 231         void *req;
 232         struct iov_iter out_iter;
 233 };
 234
 235 /* Global spinlock to protect vhost_scsi TPG list for vhost IOCTL access */
 236 static DEFINE_MUTEX(vhost_scsi_mutex);
 237 static LIST_HEAD(vhost_scsi_list);
 238
 239 static void vhost_scsi_done_inflight(struct kref *kref)
 240 {
 241         struct vhost_scsi_inflight *inflight;
 242
 243         inflight = container_of(kref, struct vhost_scsi_inflight, kref);
 244         complete(&inflight->comp);
 245 }
 246
 247 static void vhost_scsi_init_inflight(struct vhost_scsi *vs,
 248                                     struct vhost_scsi_inflight *old_inflight[])
 249 {
 250         struct vhost_scsi_inflight *new_inflight;
 251         struct vhost_virtqueue *vq;
 252         int idx, i;
 253
 254         for (i = 0; i < vs->dev.nvqs;  i++) {
 255                 vq = &vs->vqs[i].vq;
 256
 257                 mutex_lock(&vq->mutex);
 258
 259                 /* store old infight */
 260                 idx = vs->vqs[i].inflight_idx;
 261                 if (old_inflight)
 262                         old_inflight[i] = &vs->vqs[i].inflights[idx];
 263
 264                 /* setup new infight */
 265                 vs->vqs[i].inflight_idx = idx ^ 1;
 266                 new_inflight = &vs->vqs[i].inflights[idx ^ 1];
 267                 kref_init(&new_inflight->kref);
 268                 init_completion(&new_inflight->comp);
 269
 270                 mutex_unlock(&vq->mutex);
 271         }
 272 }
 273
 274 static struct vhost_scsi_inflight *
 275 vhost_scsi_get_inflight(struct vhost_virtqueue *vq)
 276 {
 277         struct vhost_scsi_inflight *inflight;
 278         struct vhost_scsi_virtqueue *svq;
 279
 280         svq = container_of(vq, struct vhost_scsi_virtqueue, vq);
 281         inflight = &svq->inflights[svq->inflight_idx];
 282         kref_get(&inflight->kref);
 283
 284         return inflight;
 285 }
 286
 287 static void vhost_scsi_put_inflight(struct vhost_scsi_inflight *inflight)
 288 {
 289         kref_put(&inflight->kref, vhost_scsi_done_inflight);
 290 }
 291
 292 static int vhost_scsi_check_true(struct se_portal_group *se_tpg)
 293 {
 294         return 1;
 295 }
 296
 297 static int vhost_scsi_check_false(struct se_portal_group *se_tpg)
 298 {
 299         return 0;
 300 }
 301
 302 static char *vhost_scsi_get_fabric_wwn(struct se_portal_group *se_tpg)
 303 {
 304         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 305                                 struct vhost_scsi_tpg, se_tpg);
 306         struct vhost_scsi_tport *tport = tpg->tport;
 307
 308         return &tport->tport_name[0];
 309 }
 310
 311 static u16 vhost_scsi_get_tpgt(struct se_portal_group *se_tpg)
 312 {
 313         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 314                                 struct vhost_scsi_tpg, se_tpg);
 315         return tpg->tport_tpgt;
 316 }
 317
 318 static int vhost_scsi_check_prot_fabric_only(struct se_portal_group *se_tpg)
 319 {
 320         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 321                                 struct vhost_scsi_tpg, se_tpg);
 322
 323         return tpg->tv_fabric_prot_type;
 324 }
 325
 326 static u32 vhost_scsi_tpg_get_inst_index(struct se_portal_group *se_tpg)
 327 {
 328         return 1;
 329 }
 330
 331 static void vhost_scsi_release_cmd_res(struct se_cmd *se_cmd)
 332 {
 333         struct vhost_scsi_cmd *tv_cmd = container_of(se_cmd,
 334                                 struct vhost_scsi_cmd, tvc_se_cmd);
 335         struct vhost_scsi_virtqueue *svq = container_of(tv_cmd->tvc_vq,
 336                                 struct vhost_scsi_virtqueue, vq);
 337         struct vhost_scsi_inflight *inflight = tv_cmd->inflight;
 338         int i;
 339
 340         if (tv_cmd->tvc_sgl_count) {
 341                 for (i = 0; i < tv_cmd->tvc_sgl_count; i++)
 342                         put_page(sg_page(&tv_cmd->tvc_sgl[i]));
 343         }
 344         if (tv_cmd->tvc_prot_sgl_count) {
 345                 for (i = 0; i < tv_cmd->tvc_prot_sgl_count; i++)
 346                         put_page(sg_page(&tv_cmd->tvc_prot_sgl[i]));
 347         }
 348
 349         sbitmap_clear_bit(&svq->scsi_tags, se_cmd->map_tag);
 350         vhost_scsi_put_inflight(inflight);
 351 }
 352
 353 static void vhost_scsi_release_tmf_res(struct vhost_scsi_tmf *tmf)
 354 {
 355         struct vhost_scsi_tpg *tpg = tmf->tpg;
 356         struct vhost_scsi_inflight *inflight = tmf->inflight;
 357
 358         mutex_lock(&tpg->tv_tpg_mutex);
 359         list_add_tail(&tpg->tmf_queue, &tmf->queue_entry);
 360         mutex_unlock(&tpg->tv_tpg_mutex);
 361         vhost_scsi_put_inflight(inflight);
 362 }
 363
 364 static void vhost_scsi_release_cmd(struct se_cmd *se_cmd)
 365 {
 366         if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB) {
 367                 struct vhost_scsi_tmf *tmf = container_of(se_cmd,
 368                                         struct vhost_scsi_tmf, se_cmd);
 369
 370                 vhost_work_queue(&tmf->vhost->dev, &tmf->vwork);
 371         } else {
 372                 struct vhost_scsi_cmd *cmd = container_of(se_cmd,
 373                                         struct vhost_scsi_cmd, tvc_se_cmd);
 374                 struct vhost_scsi *vs = cmd->tvc_vhost;
 375
 376                 llist_add(&cmd->tvc_completion_list, &vs->vs_completion_list);
 377                 vhost_work_queue(&vs->dev, &vs->vs_completion_work);
 378         }
 379 }
 380
 381 static u32 vhost_scsi_sess_get_index(struct se_session *se_sess)
 382 {
 383         return 0;
 384 }
 385
 386 static int vhost_scsi_write_pending(struct se_cmd *se_cmd)
 387 {
 388         /* Go ahead and process the write immediately */
 389         target_execute_cmd(se_cmd);
 390         return 0;
 391 }
 392
 393 static void vhost_scsi_set_default_node_attrs(struct se_node_acl *nacl)
 394 {
 395         return;
 396 }
 397
 398 static int vhost_scsi_get_cmd_state(struct se_cmd *se_cmd)
 399 {
 400         return 0;
 401 }
 402
 403 static int vhost_scsi_queue_data_in(struct se_cmd *se_cmd)
 404 {
 405         transport_generic_free_cmd(se_cmd, 0);
 406         return 0;
 407 }
 408
 409 static int vhost_scsi_queue_status(struct se_cmd *se_cmd)
 410 {
 411         transport_generic_free_cmd(se_cmd, 0);
 412         return 0;
 413 }
 414
 415 static void vhost_scsi_queue_tm_rsp(struct se_cmd *se_cmd)
 416 {
 417         struct vhost_scsi_tmf *tmf = container_of(se_cmd, struct vhost_scsi_tmf,
 418                                                   se_cmd);
 419
 420         tmf->scsi_resp = se_cmd->se_tmr_req->response;
 421         transport_generic_free_cmd(&tmf->se_cmd, 0);
 422 }
 423
 424 static void vhost_scsi_aborted_task(struct se_cmd *se_cmd)
 425 {
 426         return;
 427 }
 428
 429 static void vhost_scsi_free_evt(struct vhost_scsi *vs, struct vhost_scsi_evt *evt)
 430 {
 431         vs->vs_events_nr--;
 432         kfree(evt);
 433 }
 434
 435 static struct vhost_scsi_evt *
 436 vhost_scsi_allocate_evt(struct vhost_scsi *vs,
 437                        u32 event, u32 reason)
 438 {
 439         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 440         struct vhost_scsi_evt *evt;
 441
 442         if (vs->vs_events_nr > VHOST_SCSI_MAX_EVENT) {
 443                 vs->vs_events_missed = true;
 444                 return NULL;
 445         }
 446
 447         evt = kzalloc(sizeof(*evt), GFP_KERNEL);
 448         if (!evt) {
 449                 vq_err(vq, "Failed to allocate vhost_scsi_evt\n");
 450                 vs->vs_events_missed = true;
 451                 return NULL;
 452         }
 453
 454         evt->event.event = cpu_to_vhost32(vq, event);
 455         evt->event.reason = cpu_to_vhost32(vq, reason);
 456         vs->vs_events_nr++;
 457
 458         return evt;
 459 }
 460
 461 static int vhost_scsi_check_stop_free(struct se_cmd *se_cmd)
 462 {
 463         return target_put_sess_cmd(se_cmd);
 464 }
 465
 466 static void
 467 vhost_scsi_do_evt_work(struct vhost_scsi *vs, struct vhost_scsi_evt *evt)
 468 {
 469         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 470         struct virtio_scsi_event *event = &evt->event;
 471         struct virtio_scsi_event __user *eventp;
 472         unsigned out, in;
 473         int head, ret;
 474
 475         if (!vhost_vq_get_backend(vq)) {
 476                 vs->vs_events_missed = true;
 477                 return;
 478         }
 479
 480 again:
 481         vhost_disable_notify(&vs->dev, vq);
 482         head = vhost_get_vq_desc(vq, vq->iov,
 483                         ARRAY_SIZE(vq->iov), &out, &in,
 484                         NULL, NULL);
 485         if (head < 0) {
 486                 vs->vs_events_missed = true;
 487                 return;
 488         }
 489         if (head == vq->num) {
 490                 if (vhost_enable_notify(&vs->dev, vq))
 491                         goto again;
 492                 vs->vs_events_missed = true;
 493                 return;
 494         }
 495
 496         if ((vq->iov[out].iov_len != sizeof(struct virtio_scsi_event))) {
 497                 vq_err(vq, "Expecting virtio_scsi_event, got %zu bytes\n",
 498                                 vq->iov[out].iov_len);
 499                 vs->vs_events_missed = true;
 500                 return;
 501         }
 502
 503         if (vs->vs_events_missed) {
 504                 event->event |= cpu_to_vhost32(vq, VIRTIO_SCSI_T_EVENTS_MISSED);
 505                 vs->vs_events_missed = false;
 506         }
 507
 508         eventp = vq->iov[out].iov_base;
 509         ret = __copy_to_user(eventp, event, sizeof(*event));
 510         if (!ret)
 511                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 512         else
 513                 vq_err(vq, "Faulted on vhost_scsi_send_event\n");
 514 }
 515
 516 static void vhost_scsi_evt_work(struct vhost_work *work)
 517 {
 518         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 519                                         vs_event_work);
 520         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 521         struct vhost_scsi_evt *evt, *t;
 522         struct llist_node *llnode;
 523
 524         mutex_lock(&vq->mutex);
 525         llnode = llist_del_all(&vs->vs_event_list);
 526         llist_for_each_entry_safe(evt, t, llnode, list) {
 527                 vhost_scsi_do_evt_work(vs, evt);
 528                 vhost_scsi_free_evt(vs, evt);
 529         }
 530         mutex_unlock(&vq->mutex);
 531 }
 532
 533 /* Fill in status and signal that we are done processing this command
 534  *
 535  * This is scheduled in the vhost work queue so we are called with the owner
 536  * process mm and can access the vring.
 537  */
 538 static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
 539 {
 540         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 541                                         vs_completion_work);
 542         struct virtio_scsi_cmd_resp v_rsp;
 543         struct vhost_scsi_cmd *cmd, *t;
 544         struct llist_node *llnode;
 545         struct se_cmd *se_cmd;
 546         struct iov_iter iov_iter;
 547         int ret, vq;
 548
 549         bitmap_zero(vs->compl_bitmap, vs->dev.nvqs);
 550         llnode = llist_del_all(&vs->vs_completion_list);
 551         llist_for_each_entry_safe(cmd, t, llnode, tvc_completion_list) {
 552                 se_cmd = &cmd->tvc_se_cmd;
 553
 554                 pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__,
 555                         cmd, se_cmd->residual_count, se_cmd->scsi_status);
 556
 557                 memset(&v_rsp, 0, sizeof(v_rsp));
 558                 v_rsp.resid = cpu_to_vhost32(cmd->tvc_vq, se_cmd->residual_count);
 559                 /* TODO is status_qualifier field needed? */
 560                 v_rsp.status = se_cmd->scsi_status;
 561                 v_rsp.sense_len = cpu_to_vhost32(cmd->tvc_vq,
 562                                                  se_cmd->scsi_sense_length);
 563                 memcpy(v_rsp.sense, cmd->tvc_sense_buf,
 564                        se_cmd->scsi_sense_length);
 565
 566                 iov_iter_init(&iov_iter, ITER_DEST, cmd->tvc_resp_iov,
 567                               cmd->tvc_in_iovs, sizeof(v_rsp));
 568                 ret = copy_to_iter(&v_rsp, sizeof(v_rsp), &iov_iter);
 569                 if (likely(ret == sizeof(v_rsp))) {
 570                         struct vhost_scsi_virtqueue *q;
 571                         vhost_add_used(cmd->tvc_vq, cmd->tvc_vq_desc, 0);
 572                         q = container_of(cmd->tvc_vq, struct vhost_scsi_virtqueue, vq);
 573                         vq = q - vs->vqs;
 574                         __set_bit(vq, vs->compl_bitmap);
 575                 } else
 576                         pr_err("Faulted on virtio_scsi_cmd_resp\n");
 577
 578                 vhost_scsi_release_cmd_res(se_cmd);
 579         }
 580
 581         vq = -1;
 582         while ((vq = find_next_bit(vs->compl_bitmap, vs->dev.nvqs, vq + 1))
 583                 < vs->dev.nvqs)
 584                 vhost_signal(&vs->dev, &vs->vqs[vq].vq);
 585 }
 586
 587 static struct vhost_scsi_cmd *
 588 vhost_scsi_get_cmd(struct vhost_virtqueue *vq, struct vhost_scsi_tpg *tpg,
 589                    unsigned char *cdb, u64 scsi_tag, u16 lun, u8 task_attr,
 590                    u32 exp_data_len, int data_direction)
 591 {
 592         struct vhost_scsi_virtqueue *svq = container_of(vq,
 593                                         struct vhost_scsi_virtqueue, vq);
 594         struct vhost_scsi_cmd *cmd;
 595         struct vhost_scsi_nexus *tv_nexus;
 596         struct scatterlist *sg, *prot_sg;
 597         struct iovec *tvc_resp_iov;
 598         struct page **pages;
 599         int tag;
 600
 601         tv_nexus = tpg->tpg_nexus;
 602         if (!tv_nexus) {
 603                 pr_err("Unable to locate active struct vhost_scsi_nexus\n");
 604                 return ERR_PTR(-EIO);
 605         }
 606
 607         tag = sbitmap_get(&svq->scsi_tags);
 608         if (tag < 0) {
 609                 pr_err("Unable to obtain tag for vhost_scsi_cmd\n");
 610                 return ERR_PTR(-ENOMEM);
 611         }
 612
 613         cmd = &svq->scsi_cmds[tag];
 614         sg = cmd->tvc_sgl;
 615         prot_sg = cmd->tvc_prot_sgl;
 616         pages = cmd->tvc_upages;
 617         tvc_resp_iov = cmd->tvc_resp_iov;
 618         memset(cmd, 0, sizeof(*cmd));
 619         cmd->tvc_sgl = sg;
 620         cmd->tvc_prot_sgl = prot_sg;
 621         cmd->tvc_upages = pages;
 622         cmd->tvc_se_cmd.map_tag = tag;
 623         cmd->tvc_tag = scsi_tag;
 624         cmd->tvc_lun = lun;
 625         cmd->tvc_task_attr = task_attr;
 626         cmd->tvc_exp_data_len = exp_data_len;
 627         cmd->tvc_data_direction = data_direction;
 628         cmd->tvc_nexus = tv_nexus;
 629         cmd->inflight = vhost_scsi_get_inflight(vq);
 630         cmd->tvc_resp_iov = tvc_resp_iov;
 631
 632         memcpy(cmd->tvc_cdb, cdb, VHOST_SCSI_MAX_CDB_SIZE);
 633
 634         return cmd;
 635 }
 636
 637 /*
 638  * Map a user memory range into a scatterlist
 639  *
 640  * Returns the number of scatterlist entries used or -errno on error.
 641  */
 642 static int
 643 vhost_scsi_map_to_sgl(struct vhost_scsi_cmd *cmd,
 644                       struct iov_iter *iter,
 645                       struct scatterlist *sgl,
 646                       bool write)
 647 {
 648         struct page **pages = cmd->tvc_upages;
 649         struct scatterlist *sg = sgl;
 650         ssize_t bytes;
 651         size_t offset;
 652         unsigned int npages = 0;
 653
 654         bytes = iov_iter_get_pages2(iter, pages, LONG_MAX,
 655                                 VHOST_SCSI_PREALLOC_UPAGES, &offset);
 656         /* No pages were pinned */
 657         if (bytes <= 0)
 658                 return bytes < 0 ? bytes : -EFAULT;
 659
 660         while (bytes) {
 661                 unsigned n = min_t(unsigned, PAGE_SIZE - offset, bytes);
 662                 sg_set_page(sg++, pages[npages++], n, offset);
 663                 bytes -= n;
 664                 offset = 0;
 665         }
 666         return npages;
 667 }
 668
 669 static int
 670 vhost_scsi_calc_sgls(struct iov_iter *iter, size_t bytes, int max_sgls)
 671 {
 672         int sgl_count = 0;
 673
 674         if (!iter || !iter->iov) {
 675                 pr_err("%s: iter->iov is NULL, but expected bytes: %zu"
 676                        " present\n", __func__, bytes);
 677                 return -EINVAL;
 678         }
 679
 680         sgl_count = iov_iter_npages(iter, 0xffff);
 681         if (sgl_count > max_sgls) {
 682                 pr_err("%s: requested sgl_count: %d exceeds pre-allocated"
 683                        " max_sgls: %d\n", __func__, sgl_count, max_sgls);
 684                 return -EINVAL;
 685         }
 686         return sgl_count;
 687 }
 688
 689 static int
 690 vhost_scsi_iov_to_sgl(struct vhost_scsi_cmd *cmd, bool write,
 691                       struct iov_iter *iter,
 692                       struct scatterlist *sg, int sg_count)
 693 {
 694         struct scatterlist *p = sg;
 695         int ret;
 696
 697         while (iov_iter_count(iter)) {
 698                 ret = vhost_scsi_map_to_sgl(cmd, iter, sg, write);
 699                 if (ret < 0) {
 700                         while (p < sg) {
 701                                 struct page *page = sg_page(p++);
 702                                 if (page)
 703                                         put_page(page);
 704                         }
 705                         return ret;
 706                 }
 707                 sg += ret;
 708         }
 709         return 0;
 710 }
 711
 712 static int
 713 vhost_scsi_mapal(struct vhost_scsi_cmd *cmd,
 714                  size_t prot_bytes, struct iov_iter *prot_iter,
 715                  size_t data_bytes, struct iov_iter *data_iter)
 716 {
 717         int sgl_count, ret;
 718         bool write = (cmd->tvc_data_direction == DMA_FROM_DEVICE);
 719
 720         if (prot_bytes) {
 721                 sgl_count = vhost_scsi_calc_sgls(prot_iter, prot_bytes,
 722                                                  VHOST_SCSI_PREALLOC_PROT_SGLS);
 723                 if (sgl_count < 0)
 724                         return sgl_count;
 725
 726                 sg_init_table(cmd->tvc_prot_sgl, sgl_count);
 727                 cmd->tvc_prot_sgl_count = sgl_count;
 728                 pr_debug("%s prot_sg %p prot_sgl_count %u\n", __func__,
 729                          cmd->tvc_prot_sgl, cmd->tvc_prot_sgl_count);
 730
 731                 ret = vhost_scsi_iov_to_sgl(cmd, write, prot_iter,
 732                                             cmd->tvc_prot_sgl,
 733                                             cmd->tvc_prot_sgl_count);
 734                 if (ret < 0) {
 735                         cmd->tvc_prot_sgl_count = 0;
 736                         return ret;
 737                 }
 738         }
 739         sgl_count = vhost_scsi_calc_sgls(data_iter, data_bytes,
 740                                          VHOST_SCSI_PREALLOC_SGLS);
 741         if (sgl_count < 0)
 742                 return sgl_count;
 743
 744         sg_init_table(cmd->tvc_sgl, sgl_count);
 745         cmd->tvc_sgl_count = sgl_count;
 746         pr_debug("%s data_sg %p data_sgl_count %u\n", __func__,
 747                   cmd->tvc_sgl, cmd->tvc_sgl_count);
 748
 749         ret = vhost_scsi_iov_to_sgl(cmd, write, data_iter,
 750                                     cmd->tvc_sgl, cmd->tvc_sgl_count);
 751         if (ret < 0) {
 752                 cmd->tvc_sgl_count = 0;
 753                 return ret;
 754         }
 755         return 0;
 756 }
 757
 758 static int vhost_scsi_to_tcm_attr(int attr)
 759 {
 760         switch (attr) {
 761         case VIRTIO_SCSI_S_SIMPLE:
 762                 return TCM_SIMPLE_TAG;
 763         case VIRTIO_SCSI_S_ORDERED:
 764                 return TCM_ORDERED_TAG;
 765         case VIRTIO_SCSI_S_HEAD:
 766                 return TCM_HEAD_TAG;
 767         case VIRTIO_SCSI_S_ACA:
 768                 return TCM_ACA_TAG;
 769         default:
 770                 break;
 771         }
 772         return TCM_SIMPLE_TAG;
 773 }
 774
 775 static void vhost_scsi_target_queue_cmd(struct vhost_scsi_cmd *cmd)
 776 {
 777         struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
 778         struct vhost_scsi_nexus *tv_nexus;
 779         struct scatterlist *sg_ptr, *sg_prot_ptr = NULL;
 780
 781         /* FIXME: BIDI operation */
 782         if (cmd->tvc_sgl_count) {
 783                 sg_ptr = cmd->tvc_sgl;
 784
 785                 if (cmd->tvc_prot_sgl_count)
 786                         sg_prot_ptr = cmd->tvc_prot_sgl;
 787                 else
 788                         se_cmd->prot_pto = true;
 789         } else {
 790                 sg_ptr = NULL;
 791         }
 792         tv_nexus = cmd->tvc_nexus;
 793
 794         se_cmd->tag = 0;
 795         target_init_cmd(se_cmd, tv_nexus->tvn_se_sess, &cmd->tvc_sense_buf[0],
 796                         cmd->tvc_lun, cmd->tvc_exp_data_len,
 797                         vhost_scsi_to_tcm_attr(cmd->tvc_task_attr),
 798                         cmd->tvc_data_direction, TARGET_SCF_ACK_KREF);
 799
 800         if (target_submit_prep(se_cmd, cmd->tvc_cdb, sg_ptr,
 801                                cmd->tvc_sgl_count, NULL, 0, sg_prot_ptr,
 802                                cmd->tvc_prot_sgl_count, GFP_KERNEL))
 803                 return;
 804
 805         target_queue_submission(se_cmd);
 806 }
 807
 808 static void
 809 vhost_scsi_send_bad_target(struct vhost_scsi *vs,
 810                            struct vhost_virtqueue *vq,
 811                            int head, unsigned out)
 812 {
 813         struct virtio_scsi_cmd_resp __user *resp;
 814         struct virtio_scsi_cmd_resp rsp;
 815         int ret;
 816
 817         memset(&rsp, 0, sizeof(rsp));
 818         rsp.response = VIRTIO_SCSI_S_BAD_TARGET;
 819         resp = vq->iov[out].iov_base;
 820         ret = __copy_to_user(resp, &rsp, sizeof(rsp));
 821         if (!ret)
 822                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 823         else
 824                 pr_err("Faulted on virtio_scsi_cmd_resp\n");
 825 }
 826
 827 static int
 828 vhost_scsi_get_desc(struct vhost_scsi *vs, struct vhost_virtqueue *vq,
 829                     struct vhost_scsi_ctx *vc)
 830 {
 831         int ret = -ENXIO;
 832
 833         vc->head = vhost_get_vq_desc(vq, vq->iov,
 834                                      ARRAY_SIZE(vq->iov), &vc->out, &vc->in,
 835                                      NULL, NULL);
 836
 837         pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n",
 838                  vc->head, vc->out, vc->in);
 839
 840         /* On error, stop handling until the next kick. */
 841         if (unlikely(vc->head < 0))
 842                 goto done;
 843
 844         /* Nothing new?  Wait for eventfd to tell us they refilled. */
 845         if (vc->head == vq->num) {
 846                 if (unlikely(vhost_enable_notify(&vs->dev, vq))) {
 847                         vhost_disable_notify(&vs->dev, vq);
 848                         ret = -EAGAIN;
 849                 }
 850                 goto done;
 851         }
 852
 853         /*
 854          * Get the size of request and response buffers.
 855          * FIXME: Not correct for BIDI operation
 856          */
 857         vc->out_size = iov_length(vq->iov, vc->out);
 858         vc->in_size = iov_length(&vq->iov[vc->out], vc->in);
 859
 860         /*
 861          * Copy over the virtio-scsi request header, which for a
 862          * ANY_LAYOUT enabled guest may span multiple iovecs, or a
 863          * single iovec may contain both the header + outgoing
 864          * WRITE payloads.
 865          *
 866          * copy_from_iter() will advance out_iter, so that it will
 867          * point at the start of the outgoing WRITE payload, if
 868          * DMA_TO_DEVICE is set.
 869          */
 870         iov_iter_init(&vc->out_iter, ITER_SOURCE, vq->iov, vc->out, vc->out_size);
 871         ret = 0;
 872
 873 done:
 874         return ret;
 875 }
 876
 877 static int
 878 vhost_scsi_chk_size(struct vhost_virtqueue *vq, struct vhost_scsi_ctx *vc)
 879 {
 880         if (unlikely(vc->in_size < vc->rsp_size)) {
 881                 vq_err(vq,
 882                        "Response buf too small, need min %zu bytes got %zu",
 883                        vc->rsp_size, vc->in_size);
 884                 return -EINVAL;
 885         } else if (unlikely(vc->out_size < vc->req_size)) {
 886                 vq_err(vq,
 887                        "Request buf too small, need min %zu bytes got %zu",
 888                        vc->req_size, vc->out_size);
 889                 return -EIO;
 890         }
 891
 892         return 0;
 893 }
 894
 895 static int
 896 vhost_scsi_get_req(struct vhost_virtqueue *vq, struct vhost_scsi_ctx *vc,
 897                    struct vhost_scsi_tpg **tpgp)
 898 {
 899         int ret = -EIO;
 900
 901         if (unlikely(!copy_from_iter_full(vc->req, vc->req_size,
 902                                           &vc->out_iter))) {
 903                 vq_err(vq, "Faulted on copy_from_iter_full\n");
 904         } else if (unlikely(*vc->lunp != 1)) {
 905                 /* virtio-scsi spec requires byte 0 of the lun to be 1 */
 906                 vq_err(vq, "Illegal virtio-scsi lun: %u\n", *vc->lunp);
 907         } else {
 908                 struct vhost_scsi_tpg **vs_tpg, *tpg;
 909
 910                 vs_tpg = vhost_vq_get_backend(vq);      /* validated at handler entry */
 911
 912                 tpg = READ_ONCE(vs_tpg[*vc->target]);
 913                 if (unlikely(!tpg)) {
 914                         vq_err(vq, "Target 0x%x does not exist\n", *vc->target);
 915                 } else {
 916                         if (tpgp)
 917                                 *tpgp = tpg;
 918                         ret = 0;
 919                 }
 920         }
 921
 922         return ret;
 923 }
 924
 925 static u16 vhost_buf_to_lun(u8 *lun_buf)
 926 {
 927         return ((lun_buf[2] << 8) | lun_buf[3]) & 0x3FFF;
 928 }
 929
 930 static void
 931 vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
 932 {
 933         struct vhost_scsi_tpg **vs_tpg, *tpg;
 934         struct virtio_scsi_cmd_req v_req;
 935         struct virtio_scsi_cmd_req_pi v_req_pi;
 936         struct vhost_scsi_ctx vc;
 937         struct vhost_scsi_cmd *cmd;
 938         struct iov_iter in_iter, prot_iter, data_iter;
 939         u64 tag;
 940         u32 exp_data_len, data_direction;
 941         int ret, prot_bytes, i, c = 0;
 942         u16 lun;
 943         u8 task_attr;
 944         bool t10_pi = vhost_has_feature(vq, VIRTIO_SCSI_F_T10_PI);
 945         void *cdb;
 946
 947         mutex_lock(&vq->mutex);
 948         /*
 949          * We can handle the vq only after the endpoint is setup by calling the
 950          * VHOST_SCSI_SET_ENDPOINT ioctl.
 951          */
 952         vs_tpg = vhost_vq_get_backend(vq);
 953         if (!vs_tpg)
 954                 goto out;
 955
 956         memset(&vc, 0, sizeof(vc));
 957         vc.rsp_size = sizeof(struct virtio_scsi_cmd_resp);
 958
 959         vhost_disable_notify(&vs->dev, vq);
 960
 961         do {
 962                 ret = vhost_scsi_get_desc(vs, vq, &vc);
 963                 if (ret)
 964                         goto err;
 965
 966                 /*
 967                  * Setup pointers and values based upon different virtio-scsi
 968                  * request header if T10_PI is enabled in KVM guest.
 969                  */
 970                 if (t10_pi) {
 971                         vc.req = &v_req_pi;
 972                         vc.req_size = sizeof(v_req_pi);
 973                         vc.lunp = &v_req_pi.lun[0];
 974                         vc.target = &v_req_pi.lun[1];
 975                 } else {
 976                         vc.req = &v_req;
 977                         vc.req_size = sizeof(v_req);
 978                         vc.lunp = &v_req.lun[0];
 979                         vc.target = &v_req.lun[1];
 980                 }
 981
 982                 /*
 983                  * Validate the size of request and response buffers.
 984                  * Check for a sane response buffer so we can report
 985                  * early errors back to the guest.
 986                  */
 987                 ret = vhost_scsi_chk_size(vq, &vc);
 988                 if (ret)
 989                         goto err;
 990
 991                 ret = vhost_scsi_get_req(vq, &vc, &tpg);
 992                 if (ret)
 993                         goto err;
 994
 995                 ret = -EIO;     /* bad target on any error from here on */
 996
 997                 /*
 998                  * Determine data_direction by calculating the total outgoing
 999                  * iovec sizes + incoming iovec sizes vs. virtio-scsi request +
1000                  * response headers respectively.
1001                  *
1002                  * For DMA_TO_DEVICE this is out_iter, which is already pointing
1003                  * to the right place.
1004                  *
1005                  * For DMA_FROM_DEVICE, the iovec will be just past the end
1006                  * of the virtio-scsi response header in either the same
1007                  * or immediately following iovec.
1008                  *
1009                  * Any associated T10_PI bytes for the outgoing / incoming
1010                  * payloads are included in calculation of exp_data_len here.
1011                  */
1012                 prot_bytes = 0;
1013
1014                 if (vc.out_size > vc.req_size) {
1015                         data_direction = DMA_TO_DEVICE;
1016                         exp_data_len = vc.out_size - vc.req_size;
1017                         data_iter = vc.out_iter;
1018                 } else if (vc.in_size > vc.rsp_size) {
1019                         data_direction = DMA_FROM_DEVICE;
1020                         exp_data_len = vc.in_size - vc.rsp_size;
1021
1022                         iov_iter_init(&in_iter, ITER_DEST, &vq->iov[vc.out], vc.in,
1023                                       vc.rsp_size + exp_data_len);
1024                         iov_iter_advance(&in_iter, vc.rsp_size);
1025                         data_iter = in_iter;
1026                 } else {
1027                         data_direction = DMA_NONE;
1028                         exp_data_len = 0;
1029                 }
1030                 /*
1031                  * If T10_PI header + payload is present, setup prot_iter values
1032                  * and recalculate data_iter for vhost_scsi_mapal() mapping to
1033                  * host scatterlists via get_user_pages_fast().
1034                  */
1035                 if (t10_pi) {
1036                         if (v_req_pi.pi_bytesout) {
1037                                 if (data_direction != DMA_TO_DEVICE) {
1038                                         vq_err(vq, "Received non zero pi_bytesout,"
1039                                                 " but wrong data_direction\n");
1040                                         goto err;
1041                                 }
1042                                 prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesout);
1043                         } else if (v_req_pi.pi_bytesin) {
1044                                 if (data_direction != DMA_FROM_DEVICE) {
1045                                         vq_err(vq, "Received non zero pi_bytesin,"
1046                                                 " but wrong data_direction\n");
1047                                         goto err;
1048                                 }
1049                                 prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesin);
1050                         }
1051                         /*
1052                          * Set prot_iter to data_iter and truncate it to
1053                          * prot_bytes, and advance data_iter past any
1054                          * preceeding prot_bytes that may be present.
1055                          *
1056                          * Also fix up the exp_data_len to reflect only the
1057                          * actual data payload length.
1058                          */
1059                         if (prot_bytes) {
1060                                 exp_data_len -= prot_bytes;
1061                                 prot_iter = data_iter;
1062                                 iov_iter_truncate(&prot_iter, prot_bytes);
1063                                 iov_iter_advance(&data_iter, prot_bytes);
1064                         }
1065                         tag = vhost64_to_cpu(vq, v_req_pi.tag);
1066                         task_attr = v_req_pi.task_attr;
1067                         cdb = &v_req_pi.cdb[0];
1068                         lun = vhost_buf_to_lun(v_req_pi.lun);
1069                 } else {
1070                         tag = vhost64_to_cpu(vq, v_req.tag);
1071                         task_attr = v_req.task_attr;
1072                         cdb = &v_req.cdb[0];
1073                         lun = vhost_buf_to_lun(v_req.lun);
1074                 }
1075                 /*
1076                  * Check that the received CDB size does not exceeded our
1077                  * hardcoded max for vhost-scsi, then get a pre-allocated
1078                  * cmd descriptor for the new virtio-scsi tag.
1079                  *
1080                  * TODO what if cdb was too small for varlen cdb header?
1081                  */
1082                 if (unlikely(scsi_command_size(cdb) > VHOST_SCSI_MAX_CDB_SIZE)) {
1083                         vq_err(vq, "Received SCSI CDB with command_size: %d that"
1084                                 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1085                                 scsi_command_size(cdb), VHOST_SCSI_MAX_CDB_SIZE);
1086                                 goto err;
1087                 }
1088                 cmd = vhost_scsi_get_cmd(vq, tpg, cdb, tag, lun, task_attr,
1089                                          exp_data_len + prot_bytes,
1090                                          data_direction);
1091                 if (IS_ERR(cmd)) {
1092                         vq_err(vq, "vhost_scsi_get_cmd failed %ld\n",
1093                                PTR_ERR(cmd));
1094                         goto err;
1095                 }
1096                 cmd->tvc_vhost = vs;
1097                 cmd->tvc_vq = vq;
1098                 for (i = 0; i < vc.in ; i++)
1099                         cmd->tvc_resp_iov[i] = vq->iov[vc.out + i];
1100                 cmd->tvc_in_iovs = vc.in;
1101
1102                 pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n",
1103                          cmd->tvc_cdb[0], cmd->tvc_lun);
1104                 pr_debug("cmd: %p exp_data_len: %d, prot_bytes: %d data_direction:"
1105                          " %d\n", cmd, exp_data_len, prot_bytes, data_direction);
1106
1107                 if (data_direction != DMA_NONE) {
1108                         if (unlikely(vhost_scsi_mapal(cmd, prot_bytes,
1109                                                       &prot_iter, exp_data_len,
1110                                                       &data_iter))) {
1111                                 vq_err(vq, "Failed to map iov to sgl\n");
1112                                 vhost_scsi_release_cmd_res(&cmd->tvc_se_cmd);
1113                                 goto err;
1114                         }
1115                 }
1116                 /*
1117                  * Save the descriptor from vhost_get_vq_desc() to be used to
1118                  * complete the virtio-scsi request in TCM callback context via
1119                  * vhost_scsi_queue_data_in() and vhost_scsi_queue_status()
1120                  */
1121                 cmd->tvc_vq_desc = vc.head;
1122                 vhost_scsi_target_queue_cmd(cmd);
1123                 ret = 0;
1124 err:
1125                 /*
1126                  * ENXIO:  No more requests, or read error, wait for next kick
1127                  * EINVAL: Invalid response buffer, drop the request
1128                  * EIO:    Respond with bad target
1129                  * EAGAIN: Pending request
1130                  */
1131                 if (ret == -ENXIO)
1132                         break;
1133                 else if (ret == -EIO)
1134                         vhost_scsi_send_bad_target(vs, vq, vc.head, vc.out);
1135         } while (likely(!vhost_exceeds_weight(vq, ++c, 0)));
1136 out:
1137         mutex_unlock(&vq->mutex);
1138 }
1139
1140 static void
1141 vhost_scsi_send_tmf_resp(struct vhost_scsi *vs, struct vhost_virtqueue *vq,
1142                          int in_iovs, int vq_desc, struct iovec *resp_iov,
1143                          int tmf_resp_code)
1144 {
1145         struct virtio_scsi_ctrl_tmf_resp rsp;
1146         struct iov_iter iov_iter;
1147         int ret;
1148
1149         pr_debug("%s\n", __func__);
1150         memset(&rsp, 0, sizeof(rsp));
1151         rsp.response = tmf_resp_code;
1152
1153         iov_iter_init(&iov_iter, ITER_DEST, resp_iov, in_iovs, sizeof(rsp));
1154
1155         ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter);
1156         if (likely(ret == sizeof(rsp)))
1157                 vhost_add_used_and_signal(&vs->dev, vq, vq_desc, 0);
1158         else
1159                 pr_err("Faulted on virtio_scsi_ctrl_tmf_resp\n");
1160 }
1161
1162 static void vhost_scsi_tmf_resp_work(struct vhost_work *work)
1163 {
1164         struct vhost_scsi_tmf *tmf = container_of(work, struct vhost_scsi_tmf,
1165                                                   vwork);
1166         int resp_code;
1167
1168         if (tmf->scsi_resp == TMR_FUNCTION_COMPLETE)
1169                 resp_code = VIRTIO_SCSI_S_FUNCTION_SUCCEEDED;
1170         else
1171                 resp_code = VIRTIO_SCSI_S_FUNCTION_REJECTED;
1172
1173         vhost_scsi_send_tmf_resp(tmf->vhost, &tmf->svq->vq, tmf->in_iovs,
1174                                  tmf->vq_desc, &tmf->resp_iov, resp_code);
1175         vhost_scsi_release_tmf_res(tmf);
1176 }
1177
1178 static void
1179 vhost_scsi_handle_tmf(struct vhost_scsi *vs, struct vhost_scsi_tpg *tpg,
1180                       struct vhost_virtqueue *vq,
1181                       struct virtio_scsi_ctrl_tmf_req *vtmf,
1182                       struct vhost_scsi_ctx *vc)
1183 {
1184         struct vhost_scsi_virtqueue *svq = container_of(vq,
1185                                         struct vhost_scsi_virtqueue, vq);
1186         struct vhost_scsi_tmf *tmf;
1187
1188         if (vhost32_to_cpu(vq, vtmf->subtype) !=
1189             VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET)
1190                 goto send_reject;
1191
1192         if (!tpg->tpg_nexus || !tpg->tpg_nexus->tvn_se_sess) {
1193                 pr_err("Unable to locate active struct vhost_scsi_nexus for LUN RESET.\n");
1194                 goto send_reject;
1195         }
1196
1197         mutex_lock(&tpg->tv_tpg_mutex);
1198         if (list_empty(&tpg->tmf_queue)) {
1199                 pr_err("Missing reserve TMF. Could not handle LUN RESET.\n");
1200                 mutex_unlock(&tpg->tv_tpg_mutex);
1201                 goto send_reject;
1202         }
1203
1204         tmf = list_first_entry(&tpg->tmf_queue, struct vhost_scsi_tmf,
1205                                queue_entry);
1206         list_del_init(&tmf->queue_entry);
1207         mutex_unlock(&tpg->tv_tpg_mutex);
1208
1209         tmf->tpg = tpg;
1210         tmf->vhost = vs;
1211         tmf->svq = svq;
1212         tmf->resp_iov = vq->iov[vc->out];
1213         tmf->vq_desc = vc->head;
1214         tmf->in_iovs = vc->in;
1215         tmf->inflight = vhost_scsi_get_inflight(vq);
1216
1217         if (target_submit_tmr(&tmf->se_cmd, tpg->tpg_nexus->tvn_se_sess, NULL,
1218                               vhost_buf_to_lun(vtmf->lun), NULL,
1219                               TMR_LUN_RESET, GFP_KERNEL, 0,
1220                               TARGET_SCF_ACK_KREF) < 0) {
1221                 vhost_scsi_release_tmf_res(tmf);
1222                 goto send_reject;
1223         }
1224
1225         return;
1226
1227 send_reject:
1228         vhost_scsi_send_tmf_resp(vs, vq, vc->in, vc->head, &vq->iov[vc->out],
1229                                  VIRTIO_SCSI_S_FUNCTION_REJECTED);
1230 }
1231
1232 static void
1233 vhost_scsi_send_an_resp(struct vhost_scsi *vs,
1234                         struct vhost_virtqueue *vq,
1235                         struct vhost_scsi_ctx *vc)
1236 {
1237         struct virtio_scsi_ctrl_an_resp rsp;
1238         struct iov_iter iov_iter;
1239         int ret;
1240
1241         pr_debug("%s\n", __func__);
1242         memset(&rsp, 0, sizeof(rsp));   /* event_actual = 0 */
1243         rsp.response = VIRTIO_SCSI_S_OK;
1244
1245         iov_iter_init(&iov_iter, ITER_DEST, &vq->iov[vc->out], vc->in, sizeof(rsp));
1246
1247         ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter);
1248         if (likely(ret == sizeof(rsp)))
1249                 vhost_add_used_and_signal(&vs->dev, vq, vc->head, 0);
1250         else
1251                 pr_err("Faulted on virtio_scsi_ctrl_an_resp\n");
1252 }
1253
1254 static void
1255 vhost_scsi_ctl_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
1256 {
1257         struct vhost_scsi_tpg *tpg;
1258         union {
1259                 __virtio32 type;
1260                 struct virtio_scsi_ctrl_an_req an;
1261                 struct virtio_scsi_ctrl_tmf_req tmf;
1262         } v_req;
1263         struct vhost_scsi_ctx vc;
1264         size_t typ_size;
1265         int ret, c = 0;
1266
1267         mutex_lock(&vq->mutex);
1268         /*
1269          * We can handle the vq only after the endpoint is setup by calling the
1270          * VHOST_SCSI_SET_ENDPOINT ioctl.
1271          */
1272         if (!vhost_vq_get_backend(vq))
1273                 goto out;
1274
1275         memset(&vc, 0, sizeof(vc));
1276
1277         vhost_disable_notify(&vs->dev, vq);
1278
1279         do {
1280                 ret = vhost_scsi_get_desc(vs, vq, &vc);
1281                 if (ret)
1282                         goto err;
1283
1284                 /*
1285                  * Get the request type first in order to setup
1286                  * other parameters dependent on the type.
1287                  */
1288                 vc.req = &v_req.type;
1289                 typ_size = sizeof(v_req.type);
1290
1291                 if (unlikely(!copy_from_iter_full(vc.req, typ_size,
1292                                                   &vc.out_iter))) {
1293                         vq_err(vq, "Faulted on copy_from_iter tmf type\n");
1294                         /*
1295                          * The size of the response buffer depends on the
1296                          * request type and must be validated against it.
1297                          * Since the request type is not known, don't send
1298                          * a response.
1299                          */
1300                         continue;
1301                 }
1302
1303                 switch (vhost32_to_cpu(vq, v_req.type)) {
1304                 case VIRTIO_SCSI_T_TMF:
1305                         vc.req = &v_req.tmf;
1306                         vc.req_size = sizeof(struct virtio_scsi_ctrl_tmf_req);
1307                         vc.rsp_size = sizeof(struct virtio_scsi_ctrl_tmf_resp);
1308                         vc.lunp = &v_req.tmf.lun[0];
1309                         vc.target = &v_req.tmf.lun[1];
1310                         break;
1311                 case VIRTIO_SCSI_T_AN_QUERY:
1312                 case VIRTIO_SCSI_T_AN_SUBSCRIBE:
1313                         vc.req = &v_req.an;
1314                         vc.req_size = sizeof(struct virtio_scsi_ctrl_an_req);
1315                         vc.rsp_size = sizeof(struct virtio_scsi_ctrl_an_resp);
1316                         vc.lunp = &v_req.an.lun[0];
1317                         vc.target = NULL;
1318                         break;
1319                 default:
1320                         vq_err(vq, "Unknown control request %d", v_req.type);
1321                         continue;
1322                 }
1323
1324                 /*
1325                  * Validate the size of request and response buffers.
1326                  * Check for a sane response buffer so we can report
1327                  * early errors back to the guest.
1328                  */
1329                 ret = vhost_scsi_chk_size(vq, &vc);
1330                 if (ret)
1331                         goto err;
1332
1333                 /*
1334                  * Get the rest of the request now that its size is known.
1335                  */
1336                 vc.req += typ_size;
1337                 vc.req_size -= typ_size;
1338
1339                 ret = vhost_scsi_get_req(vq, &vc, &tpg);
1340                 if (ret)
1341                         goto err;
1342
1343                 if (v_req.type == VIRTIO_SCSI_T_TMF)
1344                         vhost_scsi_handle_tmf(vs, tpg, vq, &v_req.tmf, &vc);
1345                 else
1346                         vhost_scsi_send_an_resp(vs, vq, &vc);
1347 err:
1348                 /*
1349                  * ENXIO:  No more requests, or read error, wait for next kick
1350                  * EINVAL: Invalid response buffer, drop the request
1351                  * EIO:    Respond with bad target
1352                  * EAGAIN: Pending request
1353                  */
1354                 if (ret == -ENXIO)
1355                         break;
1356                 else if (ret == -EIO)
1357                         vhost_scsi_send_bad_target(vs, vq, vc.head, vc.out);
1358         } while (likely(!vhost_exceeds_weight(vq, ++c, 0)));
1359 out:
1360         mutex_unlock(&vq->mutex);
1361 }
1362
1363 static void vhost_scsi_ctl_handle_kick(struct vhost_work *work)
1364 {
1365         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1366                                                 poll.work);
1367         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1368
1369         pr_debug("%s: The handling func for control queue.\n", __func__);
1370         vhost_scsi_ctl_handle_vq(vs, vq);
1371 }
1372
1373 static void
1374 vhost_scsi_send_evt(struct vhost_scsi *vs,
1375                    struct vhost_scsi_tpg *tpg,
1376                    struct se_lun *lun,
1377                    u32 event,
1378                    u32 reason)
1379 {
1380         struct vhost_scsi_evt *evt;
1381
1382         evt = vhost_scsi_allocate_evt(vs, event, reason);
1383         if (!evt)
1384                 return;
1385
1386         if (tpg && lun) {
1387                 /* TODO: share lun setup code with virtio-scsi.ko */
1388                 /*
1389                  * Note: evt->event is zeroed when we allocate it and
1390                  * lun[4-7] need to be zero according to virtio-scsi spec.
1391                  */
1392                 evt->event.lun[0] = 0x01;
1393                 evt->event.lun[1] = tpg->tport_tpgt;
1394                 if (lun->unpacked_lun >= 256)
1395                         evt->event.lun[2] = lun->unpacked_lun >> 8 | 0x40 ;
1396                 evt->event.lun[3] = lun->unpacked_lun & 0xFF;
1397         }
1398
1399         llist_add(&evt->list, &vs->vs_event_list);
1400         vhost_work_queue(&vs->dev, &vs->vs_event_work);
1401 }
1402
1403 static void vhost_scsi_evt_handle_kick(struct vhost_work *work)
1404 {
1405         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1406                                                 poll.work);
1407         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1408
1409         mutex_lock(&vq->mutex);
1410         if (!vhost_vq_get_backend(vq))
1411                 goto out;
1412
1413         if (vs->vs_events_missed)
1414                 vhost_scsi_send_evt(vs, NULL, NULL, VIRTIO_SCSI_T_NO_EVENT, 0);
1415 out:
1416         mutex_unlock(&vq->mutex);
1417 }
1418
1419 static void vhost_scsi_handle_kick(struct vhost_work *work)
1420 {
1421         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1422                                                 poll.work);
1423         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1424
1425         vhost_scsi_handle_vq(vs, vq);
1426 }
1427
1428 /* Callers must hold dev mutex */
1429 static void vhost_scsi_flush(struct vhost_scsi *vs)
1430 {
1431         int i;
1432
1433         /* Init new inflight and remember the old inflight */
1434         vhost_scsi_init_inflight(vs, vs->old_inflight);
1435
1436         /*
1437          * The inflight->kref was initialized to 1. We decrement it here to
1438          * indicate the start of the flush operation so that it will reach 0
1439          * when all the reqs are finished.
1440          */
1441         for (i = 0; i < vs->dev.nvqs; i++)
1442                 kref_put(&vs->old_inflight[i]->kref, vhost_scsi_done_inflight);
1443
1444         /* Flush both the vhost poll and vhost work */
1445         vhost_dev_flush(&vs->dev);
1446
1447         /* Wait for all reqs issued before the flush to be finished */
1448         for (i = 0; i < vs->dev.nvqs; i++)
1449                 wait_for_completion(&vs->old_inflight[i]->comp);
1450 }
1451
1452 static void vhost_scsi_destroy_vq_cmds(struct vhost_virtqueue *vq)
1453 {
1454         struct vhost_scsi_virtqueue *svq = container_of(vq,
1455                                         struct vhost_scsi_virtqueue, vq);
1456         struct vhost_scsi_cmd *tv_cmd;
1457         unsigned int i;
1458
1459         if (!svq->scsi_cmds)
1460                 return;
1461
1462         for (i = 0; i < svq->max_cmds; i++) {
1463                 tv_cmd = &svq->scsi_cmds[i];
1464
1465                 kfree(tv_cmd->tvc_sgl);
1466                 kfree(tv_cmd->tvc_prot_sgl);
1467                 kfree(tv_cmd->tvc_upages);
1468                 kfree(tv_cmd->tvc_resp_iov);
1469         }
1470
1471         sbitmap_free(&svq->scsi_tags);
1472         kfree(svq->scsi_cmds);
1473         svq->scsi_cmds = NULL;
1474 }
1475
1476 static int vhost_scsi_setup_vq_cmds(struct vhost_virtqueue *vq, int max_cmds)
1477 {
1478         struct vhost_scsi_virtqueue *svq = container_of(vq,
1479                                         struct vhost_scsi_virtqueue, vq);
1480         struct vhost_scsi_cmd *tv_cmd;
1481         unsigned int i;
1482
1483         if (svq->scsi_cmds)
1484                 return 0;
1485
1486         if (sbitmap_init_node(&svq->scsi_tags, max_cmds, -1, GFP_KERNEL,
1487                               NUMA_NO_NODE, false, true))
1488                 return -ENOMEM;
1489         svq->max_cmds = max_cmds;
1490
1491         svq->scsi_cmds = kcalloc(max_cmds, sizeof(*tv_cmd), GFP_KERNEL);
1492         if (!svq->scsi_cmds) {
1493                 sbitmap_free(&svq->scsi_tags);
1494                 return -ENOMEM;
1495         }
1496
1497         for (i = 0; i < max_cmds; i++) {
1498                 tv_cmd = &svq->scsi_cmds[i];
1499
1500                 tv_cmd->tvc_sgl = kcalloc(VHOST_SCSI_PREALLOC_SGLS,
1501                                           sizeof(struct scatterlist),
1502                                           GFP_KERNEL);
1503                 if (!tv_cmd->tvc_sgl) {
1504                         pr_err("Unable to allocate tv_cmd->tvc_sgl\n");
1505                         goto out;
1506                 }
1507
1508                 tv_cmd->tvc_upages = kcalloc(VHOST_SCSI_PREALLOC_UPAGES,
1509                                              sizeof(struct page *),
1510                                              GFP_KERNEL);
1511                 if (!tv_cmd->tvc_upages) {
1512                         pr_err("Unable to allocate tv_cmd->tvc_upages\n");
1513                         goto out;
1514                 }
1515
1516                 tv_cmd->tvc_resp_iov = kcalloc(UIO_MAXIOV,
1517                                                sizeof(struct iovec),
1518                                                GFP_KERNEL);
1519                 if (!tv_cmd->tvc_resp_iov) {
1520                         pr_err("Unable to allocate tv_cmd->tvc_resp_iov\n");
1521                         goto out;
1522                 }
1523
1524                 tv_cmd->tvc_prot_sgl = kcalloc(VHOST_SCSI_PREALLOC_PROT_SGLS,
1525                                                sizeof(struct scatterlist),
1526                                                GFP_KERNEL);
1527                 if (!tv_cmd->tvc_prot_sgl) {
1528                         pr_err("Unable to allocate tv_cmd->tvc_prot_sgl\n");
1529                         goto out;
1530                 }
1531         }
1532         return 0;
1533 out:
1534         vhost_scsi_destroy_vq_cmds(vq);
1535         return -ENOMEM;
1536 }
1537
1538 /*
1539  * Called from vhost_scsi_ioctl() context to walk the list of available
1540  * vhost_scsi_tpg with an active struct vhost_scsi_nexus
1541  *
1542  *  The lock nesting rule is:
1543  *    vhost_scsi_mutex -> vs->dev.mutex -> tpg->tv_tpg_mutex -> vq->mutex
1544  */
1545 static int
1546 vhost_scsi_set_endpoint(struct vhost_scsi *vs,
1547                         struct vhost_scsi_target *t)
1548 {
1549         struct se_portal_group *se_tpg;
1550         struct vhost_scsi_tport *tv_tport;
1551         struct vhost_scsi_tpg *tpg;
1552         struct vhost_scsi_tpg **vs_tpg;
1553         struct vhost_virtqueue *vq;
1554         int index, ret, i, len;
1555         bool match = false;
1556
1557         mutex_lock(&vhost_scsi_mutex);
1558         mutex_lock(&vs->dev.mutex);
1559
1560         /* Verify that ring has been setup correctly. */
1561         for (index = 0; index < vs->dev.nvqs; ++index) {
1562                 /* Verify that ring has been setup correctly. */
1563                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1564                         ret = -EFAULT;
1565                         goto out;
1566                 }
1567         }
1568
1569         len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET;
1570         vs_tpg = kzalloc(len, GFP_KERNEL);
1571         if (!vs_tpg) {
1572                 ret = -ENOMEM;
1573                 goto out;
1574         }
1575         if (vs->vs_tpg)
1576                 memcpy(vs_tpg, vs->vs_tpg, len);
1577
1578         list_for_each_entry(tpg, &vhost_scsi_list, tv_tpg_list) {
1579                 mutex_lock(&tpg->tv_tpg_mutex);
1580                 if (!tpg->tpg_nexus) {
1581                         mutex_unlock(&tpg->tv_tpg_mutex);
1582                         continue;
1583                 }
1584                 if (tpg->tv_tpg_vhost_count != 0) {
1585                         mutex_unlock(&tpg->tv_tpg_mutex);
1586                         continue;
1587                 }
1588                 tv_tport = tpg->tport;
1589
1590                 if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1591                         if (vs->vs_tpg && vs->vs_tpg[tpg->tport_tpgt]) {
1592                                 mutex_unlock(&tpg->tv_tpg_mutex);
1593                                 ret = -EEXIST;
1594                                 goto undepend;
1595                         }
1596                         /*
1597                          * In order to ensure individual vhost-scsi configfs
1598                          * groups cannot be removed while in use by vhost ioctl,
1599                          * go ahead and take an explicit se_tpg->tpg_group.cg_item
1600                          * dependency now.
1601                          */
1602                         se_tpg = &tpg->se_tpg;
1603                         ret = target_depend_item(&se_tpg->tpg_group.cg_item);
1604                         if (ret) {
1605                                 pr_warn("target_depend_item() failed: %d\n", ret);
1606                                 mutex_unlock(&tpg->tv_tpg_mutex);
1607                                 goto undepend;
1608                         }
1609                         tpg->tv_tpg_vhost_count++;
1610                         tpg->vhost_scsi = vs;
1611                         vs_tpg[tpg->tport_tpgt] = tpg;
1612                         match = true;
1613                 }
1614                 mutex_unlock(&tpg->tv_tpg_mutex);
1615         }
1616
1617         if (match) {
1618                 memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
1619                        sizeof(vs->vs_vhost_wwpn));
1620
1621                 for (i = VHOST_SCSI_VQ_IO; i < vs->dev.nvqs; i++) {
1622                         vq = &vs->vqs[i].vq;
1623                         if (!vhost_vq_is_setup(vq))
1624                                 continue;
1625
1626                         ret = vhost_scsi_setup_vq_cmds(vq, vq->num);
1627                         if (ret)
1628                                 goto destroy_vq_cmds;
1629                 }
1630
1631                 for (i = 0; i < vs->dev.nvqs; i++) {
1632                         vq = &vs->vqs[i].vq;
1633                         mutex_lock(&vq->mutex);
1634                         vhost_vq_set_backend(vq, vs_tpg);
1635                         vhost_vq_init_access(vq);
1636                         mutex_unlock(&vq->mutex);
1637                 }
1638                 ret = 0;
1639         } else {
1640                 ret = -EEXIST;
1641         }
1642
1643         /*
1644          * Act as synchronize_rcu to make sure access to
1645          * old vs->vs_tpg is finished.
1646          */
1647         vhost_scsi_flush(vs);
1648         kfree(vs->vs_tpg);
1649         vs->vs_tpg = vs_tpg;
1650         goto out;
1651
1652 destroy_vq_cmds:
1653         for (i--; i >= VHOST_SCSI_VQ_IO; i--) {
1654                 if (!vhost_vq_get_backend(&vs->vqs[i].vq))
1655                         vhost_scsi_destroy_vq_cmds(&vs->vqs[i].vq);
1656         }
1657 undepend:
1658         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1659                 tpg = vs_tpg[i];
1660                 if (tpg) {
1661                         tpg->tv_tpg_vhost_count--;
1662                         target_undepend_item(&tpg->se_tpg.tpg_group.cg_item);
1663                 }
1664         }
1665         kfree(vs_tpg);
1666 out:
1667         mutex_unlock(&vs->dev.mutex);
1668         mutex_unlock(&vhost_scsi_mutex);
1669         return ret;
1670 }
1671
1672 static int
1673 vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
1674                           struct vhost_scsi_target *t)
1675 {
1676         struct se_portal_group *se_tpg;
1677         struct vhost_scsi_tport *tv_tport;
1678         struct vhost_scsi_tpg *tpg;
1679         struct vhost_virtqueue *vq;
1680         bool match = false;
1681         int index, ret, i;
1682         u8 target;
1683
1684         mutex_lock(&vhost_scsi_mutex);
1685         mutex_lock(&vs->dev.mutex);
1686         /* Verify that ring has been setup correctly. */
1687         for (index = 0; index < vs->dev.nvqs; ++index) {
1688                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1689                         ret = -EFAULT;
1690                         goto err_dev;
1691                 }
1692         }
1693
1694         if (!vs->vs_tpg) {
1695                 ret = 0;
1696                 goto err_dev;
1697         }
1698
1699         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1700                 target = i;
1701                 tpg = vs->vs_tpg[target];
1702                 if (!tpg)
1703                         continue;
1704
1705                 mutex_lock(&tpg->tv_tpg_mutex);
1706                 tv_tport = tpg->tport;
1707                 if (!tv_tport) {
1708                         ret = -ENODEV;
1709                         goto err_tpg;
1710                 }
1711
1712                 if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1713                         pr_warn("tv_tport->tport_name: %s, tpg->tport_tpgt: %hu"
1714                                 " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
1715                                 tv_tport->tport_name, tpg->tport_tpgt,
1716                                 t->vhost_wwpn, t->vhost_tpgt);
1717                         ret = -EINVAL;
1718                         goto err_tpg;
1719                 }
1720                 tpg->tv_tpg_vhost_count--;
1721                 tpg->vhost_scsi = NULL;
1722                 vs->vs_tpg[target] = NULL;
1723                 match = true;
1724                 mutex_unlock(&tpg->tv_tpg_mutex);
1725                 /*
1726                  * Release se_tpg->tpg_group.cg_item configfs dependency now
1727                  * to allow vhost-scsi WWPN se_tpg->tpg_group shutdown to occur.
1728                  */
1729                 se_tpg = &tpg->se_tpg;
1730                 target_undepend_item(&se_tpg->tpg_group.cg_item);
1731         }
1732         if (match) {
1733                 for (i = 0; i < vs->dev.nvqs; i++) {
1734                         vq = &vs->vqs[i].vq;
1735                         mutex_lock(&vq->mutex);
1736                         vhost_vq_set_backend(vq, NULL);
1737                         mutex_unlock(&vq->mutex);
1738                 }
1739                 /* Make sure cmds are not running before tearing them down. */
1740                 vhost_scsi_flush(vs);
1741
1742                 for (i = 0; i < vs->dev.nvqs; i++) {
1743                         vq = &vs->vqs[i].vq;
1744                         vhost_scsi_destroy_vq_cmds(vq);
1745                 }
1746         }
1747         /*
1748          * Act as synchronize_rcu to make sure access to
1749          * old vs->vs_tpg is finished.
1750          */
1751         vhost_scsi_flush(vs);
1752         kfree(vs->vs_tpg);
1753         vs->vs_tpg = NULL;
1754         WARN_ON(vs->vs_events_nr);
1755         mutex_unlock(&vs->dev.mutex);
1756         mutex_unlock(&vhost_scsi_mutex);
1757         return 0;
1758
1759 err_tpg:
1760         mutex_unlock(&tpg->tv_tpg_mutex);
1761 err_dev:
1762         mutex_unlock(&vs->dev.mutex);
1763         mutex_unlock(&vhost_scsi_mutex);
1764         return ret;
1765 }
1766
1767 static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features)
1768 {
1769         struct vhost_virtqueue *vq;
1770         int i;
1771
1772         if (features & ~VHOST_SCSI_FEATURES)
1773                 return -EOPNOTSUPP;
1774
1775         mutex_lock(&vs->dev.mutex);
1776         if ((features & (1 << VHOST_F_LOG_ALL)) &&
1777             !vhost_log_access_ok(&vs->dev)) {
1778                 mutex_unlock(&vs->dev.mutex);
1779                 return -EFAULT;
1780         }
1781
1782         for (i = 0; i < vs->dev.nvqs; i++) {
1783                 vq = &vs->vqs[i].vq;
1784                 mutex_lock(&vq->mutex);
1785                 vq->acked_features = features;
1786                 mutex_unlock(&vq->mutex);
1787         }
1788         mutex_unlock(&vs->dev.mutex);
1789         return 0;
1790 }
1791
1792 static int vhost_scsi_open(struct inode *inode, struct file *f)
1793 {
1794         struct vhost_scsi *vs;
1795         struct vhost_virtqueue **vqs;
1796         int r = -ENOMEM, i, nvqs = vhost_scsi_max_io_vqs;
1797
1798         vs = kvzalloc(sizeof(*vs), GFP_KERNEL);
1799         if (!vs)
1800                 goto err_vs;
1801
1802         if (nvqs > VHOST_SCSI_MAX_IO_VQ) {
1803                 pr_err("Invalid max_io_vqs of %d. Using %d.\n", nvqs,
1804                        VHOST_SCSI_MAX_IO_VQ);
1805                 nvqs = VHOST_SCSI_MAX_IO_VQ;
1806         } else if (nvqs == 0) {
1807                 pr_err("Invalid max_io_vqs of %d. Using 1.\n", nvqs);
1808                 nvqs = 1;
1809         }
1810         nvqs += VHOST_SCSI_VQ_IO;
1811
1812         vs->compl_bitmap = bitmap_alloc(nvqs, GFP_KERNEL);
1813         if (!vs->compl_bitmap)
1814                 goto err_compl_bitmap;
1815
1816         vs->old_inflight = kmalloc_array(nvqs, sizeof(*vs->old_inflight),
1817                                          GFP_KERNEL | __GFP_ZERO);
1818         if (!vs->old_inflight)
1819                 goto err_inflight;
1820
1821         vs->vqs = kmalloc_array(nvqs, sizeof(*vs->vqs),
1822                                 GFP_KERNEL | __GFP_ZERO);
1823         if (!vs->vqs)
1824                 goto err_vqs;
1825
1826         vqs = kmalloc_array(nvqs, sizeof(*vqs), GFP_KERNEL);
1827         if (!vqs)
1828                 goto err_local_vqs;
1829
1830         vhost_work_init(&vs->vs_completion_work, vhost_scsi_complete_cmd_work);
1831         vhost_work_init(&vs->vs_event_work, vhost_scsi_evt_work);
1832
1833         vs->vs_events_nr = 0;
1834         vs->vs_events_missed = false;
1835
1836         vqs[VHOST_SCSI_VQ_CTL] = &vs->vqs[VHOST_SCSI_VQ_CTL].vq;
1837         vqs[VHOST_SCSI_VQ_EVT] = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1838         vs->vqs[VHOST_SCSI_VQ_CTL].vq.handle_kick = vhost_scsi_ctl_handle_kick;
1839         vs->vqs[VHOST_SCSI_VQ_EVT].vq.handle_kick = vhost_scsi_evt_handle_kick;
1840         for (i = VHOST_SCSI_VQ_IO; i < nvqs; i++) {
1841                 vqs[i] = &vs->vqs[i].vq;
1842                 vs->vqs[i].vq.handle_kick = vhost_scsi_handle_kick;
1843         }
1844         vhost_dev_init(&vs->dev, vqs, nvqs, UIO_MAXIOV,
1845                        VHOST_SCSI_WEIGHT, 0, true, NULL);
1846
1847         vhost_scsi_init_inflight(vs, NULL);
1848
1849         f->private_data = vs;
1850         return 0;
1851
1852 err_local_vqs:
1853         kfree(vs->vqs);
1854 err_vqs:
1855         kfree(vs->old_inflight);
1856 err_inflight:
1857         bitmap_free(vs->compl_bitmap);
1858 err_compl_bitmap:
1859         kvfree(vs);
1860 err_vs:
1861         return r;
1862 }
1863
1864 static int vhost_scsi_release(struct inode *inode, struct file *f)
1865 {
1866         struct vhost_scsi *vs = f->private_data;
1867         struct vhost_scsi_target t;
1868
1869         mutex_lock(&vs->dev.mutex);
1870         memcpy(t.vhost_wwpn, vs->vs_vhost_wwpn, sizeof(t.vhost_wwpn));
1871         mutex_unlock(&vs->dev.mutex);
1872         vhost_scsi_clear_endpoint(vs, &t);
1873         vhost_dev_stop(&vs->dev);
1874         vhost_dev_cleanup(&vs->dev);
1875         kfree(vs->dev.vqs);
1876         kfree(vs->vqs);
1877         kfree(vs->old_inflight);
1878         bitmap_free(vs->compl_bitmap);
1879         kvfree(vs);
1880         return 0;
1881 }
1882
1883 static long
1884 vhost_scsi_ioctl(struct file *f,
1885                  unsigned int ioctl,
1886                  unsigned long arg)
1887 {
1888         struct vhost_scsi *vs = f->private_data;
1889         struct vhost_scsi_target backend;
1890         void __user *argp = (void __user *)arg;
1891         u64 __user *featurep = argp;
1892         u32 __user *eventsp = argp;
1893         u32 events_missed;
1894         u64 features;
1895         int r, abi_version = VHOST_SCSI_ABI_VERSION;
1896         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1897
1898         switch (ioctl) {
1899         case VHOST_SCSI_SET_ENDPOINT:
1900                 if (copy_from_user(&backend, argp, sizeof backend))
1901                         return -EFAULT;
1902                 if (backend.reserved != 0)
1903                         return -EOPNOTSUPP;
1904
1905                 return vhost_scsi_set_endpoint(vs, &backend);
1906         case VHOST_SCSI_CLEAR_ENDPOINT:
1907                 if (copy_from_user(&backend, argp, sizeof backend))
1908                         return -EFAULT;
1909                 if (backend.reserved != 0)
1910                         return -EOPNOTSUPP;
1911
1912                 return vhost_scsi_clear_endpoint(vs, &backend);
1913         case VHOST_SCSI_GET_ABI_VERSION:
1914                 if (copy_to_user(argp, &abi_version, sizeof abi_version))
1915                         return -EFAULT;
1916                 return 0;
1917         case VHOST_SCSI_SET_EVENTS_MISSED:
1918                 if (get_user(events_missed, eventsp))
1919                         return -EFAULT;
1920                 mutex_lock(&vq->mutex);
1921                 vs->vs_events_missed = events_missed;
1922                 mutex_unlock(&vq->mutex);
1923                 return 0;
1924         case VHOST_SCSI_GET_EVENTS_MISSED:
1925                 mutex_lock(&vq->mutex);
1926                 events_missed = vs->vs_events_missed;
1927                 mutex_unlock(&vq->mutex);
1928                 if (put_user(events_missed, eventsp))
1929                         return -EFAULT;
1930                 return 0;
1931         case VHOST_GET_FEATURES:
1932                 features = VHOST_SCSI_FEATURES;
1933                 if (copy_to_user(featurep, &features, sizeof features))
1934                         return -EFAULT;
1935                 return 0;
1936         case VHOST_SET_FEATURES:
1937                 if (copy_from_user(&features, featurep, sizeof features))
1938                         return -EFAULT;
1939                 return vhost_scsi_set_features(vs, features);
1940         default:
1941                 mutex_lock(&vs->dev.mutex);
1942                 r = vhost_dev_ioctl(&vs->dev, ioctl, argp);
1943                 /* TODO: flush backend after dev ioctl. */
1944                 if (r == -ENOIOCTLCMD)
1945                         r = vhost_vring_ioctl(&vs->dev, ioctl, argp);
1946                 mutex_unlock(&vs->dev.mutex);
1947                 return r;
1948         }
1949 }
1950
1951 static const struct file_operations vhost_scsi_fops = {
1952         .owner          = THIS_MODULE,
1953         .release        = vhost_scsi_release,
1954         .unlocked_ioctl = vhost_scsi_ioctl,
1955         .compat_ioctl   = compat_ptr_ioctl,
1956         .open           = vhost_scsi_open,
1957         .llseek         = noop_llseek,
1958 };
1959
1960 static struct miscdevice vhost_scsi_misc = {
1961         MISC_DYNAMIC_MINOR,
1962         "vhost-scsi",
1963         &vhost_scsi_fops,
1964 };
1965
1966 static int __init vhost_scsi_register(void)
1967 {
1968         return misc_register(&vhost_scsi_misc);
1969 }
1970
1971 static void vhost_scsi_deregister(void)
1972 {
1973         misc_deregister(&vhost_scsi_misc);
1974 }
1975
1976 static char *vhost_scsi_dump_proto_id(struct vhost_scsi_tport *tport)
1977 {
1978         switch (tport->tport_proto_id) {
1979         case SCSI_PROTOCOL_SAS:
1980                 return "SAS";
1981         case SCSI_PROTOCOL_FCP:
1982                 return "FCP";
1983         case SCSI_PROTOCOL_ISCSI:
1984                 return "iSCSI";
1985         default:
1986                 break;
1987         }
1988
1989         return "Unknown";
1990 }
1991
1992 static void
1993 vhost_scsi_do_plug(struct vhost_scsi_tpg *tpg,
1994                   struct se_lun *lun, bool plug)
1995 {
1996
1997         struct vhost_scsi *vs = tpg->vhost_scsi;
1998         struct vhost_virtqueue *vq;
1999         u32 reason;
2000
2001         if (!vs)
2002                 return;
2003
2004         mutex_lock(&vs->dev.mutex);
2005
2006         if (plug)
2007                 reason = VIRTIO_SCSI_EVT_RESET_RESCAN;
2008         else
2009                 reason = VIRTIO_SCSI_EVT_RESET_REMOVED;
2010
2011         vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
2012         mutex_lock(&vq->mutex);
2013         if (vhost_has_feature(vq, VIRTIO_SCSI_F_HOTPLUG))
2014                 vhost_scsi_send_evt(vs, tpg, lun,
2015                                    VIRTIO_SCSI_T_TRANSPORT_RESET, reason);
2016         mutex_unlock(&vq->mutex);
2017         mutex_unlock(&vs->dev.mutex);
2018 }
2019
2020 static void vhost_scsi_hotplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
2021 {
2022         vhost_scsi_do_plug(tpg, lun, true);
2023 }
2024
2025 static void vhost_scsi_hotunplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
2026 {
2027         vhost_scsi_do_plug(tpg, lun, false);
2028 }
2029
2030 static int vhost_scsi_port_link(struct se_portal_group *se_tpg,
2031                                struct se_lun *lun)
2032 {
2033         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2034                                 struct vhost_scsi_tpg, se_tpg);
2035         struct vhost_scsi_tmf *tmf;
2036
2037         tmf = kzalloc(sizeof(*tmf), GFP_KERNEL);
2038         if (!tmf)
2039                 return -ENOMEM;
2040         INIT_LIST_HEAD(&tmf->queue_entry);
2041         vhost_work_init(&tmf->vwork, vhost_scsi_tmf_resp_work);
2042
2043         mutex_lock(&vhost_scsi_mutex);
2044
2045         mutex_lock(&tpg->tv_tpg_mutex);
2046         tpg->tv_tpg_port_count++;
2047         list_add_tail(&tmf->queue_entry, &tpg->tmf_queue);
2048         mutex_unlock(&tpg->tv_tpg_mutex);
2049
2050         vhost_scsi_hotplug(tpg, lun);
2051
2052         mutex_unlock(&vhost_scsi_mutex);
2053
2054         return 0;
2055 }
2056
2057 static void vhost_scsi_port_unlink(struct se_portal_group *se_tpg,
2058                                   struct se_lun *lun)
2059 {
2060         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2061                                 struct vhost_scsi_tpg, se_tpg);
2062         struct vhost_scsi_tmf *tmf;
2063
2064         mutex_lock(&vhost_scsi_mutex);
2065
2066         mutex_lock(&tpg->tv_tpg_mutex);
2067         tpg->tv_tpg_port_count--;
2068         tmf = list_first_entry(&tpg->tmf_queue, struct vhost_scsi_tmf,
2069                                queue_entry);
2070         list_del(&tmf->queue_entry);
2071         kfree(tmf);
2072         mutex_unlock(&tpg->tv_tpg_mutex);
2073
2074         vhost_scsi_hotunplug(tpg, lun);
2075
2076         mutex_unlock(&vhost_scsi_mutex);
2077 }
2078
2079 static ssize_t vhost_scsi_tpg_attrib_fabric_prot_type_store(
2080                 struct config_item *item, const char *page, size_t count)
2081 {
2082         struct se_portal_group *se_tpg = attrib_to_tpg(item);
2083         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2084                                 struct vhost_scsi_tpg, se_tpg);
2085         unsigned long val;
2086         int ret = kstrtoul(page, 0, &val);
2087
2088         if (ret) {
2089                 pr_err("kstrtoul() returned %d for fabric_prot_type\n", ret);
2090                 return ret;
2091         }
2092         if (val != 0 && val != 1 && val != 3) {
2093                 pr_err("Invalid vhost_scsi fabric_prot_type: %lu\n", val);
2094                 return -EINVAL;
2095         }
2096         tpg->tv_fabric_prot_type = val;
2097
2098         return count;
2099 }
2100
2101 static ssize_t vhost_scsi_tpg_attrib_fabric_prot_type_show(
2102                 struct config_item *item, char *page)
2103 {
2104         struct se_portal_group *se_tpg = attrib_to_tpg(item);
2105         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2106                                 struct vhost_scsi_tpg, se_tpg);
2107
2108         return sprintf(page, "%d\n", tpg->tv_fabric_prot_type);
2109 }
2110
2111 CONFIGFS_ATTR(vhost_scsi_tpg_attrib_, fabric_prot_type);
2112
2113 static struct configfs_attribute *vhost_scsi_tpg_attrib_attrs[] = {
2114         &vhost_scsi_tpg_attrib_attr_fabric_prot_type,
2115         NULL,
2116 };
2117
2118 static int vhost_scsi_make_nexus(struct vhost_scsi_tpg *tpg,
2119                                 const char *name)
2120 {
2121         struct vhost_scsi_nexus *tv_nexus;
2122
2123         mutex_lock(&tpg->tv_tpg_mutex);
2124         if (tpg->tpg_nexus) {
2125                 mutex_unlock(&tpg->tv_tpg_mutex);
2126                 pr_debug("tpg->tpg_nexus already exists\n");
2127                 return -EEXIST;
2128         }
2129
2130         tv_nexus = kzalloc(sizeof(*tv_nexus), GFP_KERNEL);
2131         if (!tv_nexus) {
2132                 mutex_unlock(&tpg->tv_tpg_mutex);
2133                 pr_err("Unable to allocate struct vhost_scsi_nexus\n");
2134                 return -ENOMEM;
2135         }
2136         /*
2137          * Since we are running in 'demo mode' this call with generate a
2138          * struct se_node_acl for the vhost_scsi struct se_portal_group with
2139          * the SCSI Initiator port name of the passed configfs group 'name'.
2140          */
2141         tv_nexus->tvn_se_sess = target_setup_session(&tpg->se_tpg, 0, 0,
2142                                         TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS,
2143                                         (unsigned char *)name, tv_nexus, NULL);
2144         if (IS_ERR(tv_nexus->tvn_se_sess)) {
2145                 mutex_unlock(&tpg->tv_tpg_mutex);
2146                 kfree(tv_nexus);
2147                 return -ENOMEM;
2148         }
2149         tpg->tpg_nexus = tv_nexus;
2150
2151         mutex_unlock(&tpg->tv_tpg_mutex);
2152         return 0;
2153 }
2154
2155 static int vhost_scsi_drop_nexus(struct vhost_scsi_tpg *tpg)
2156 {
2157         struct se_session *se_sess;
2158         struct vhost_scsi_nexus *tv_nexus;
2159
2160         mutex_lock(&tpg->tv_tpg_mutex);
2161         tv_nexus = tpg->tpg_nexus;
2162         if (!tv_nexus) {
2163                 mutex_unlock(&tpg->tv_tpg_mutex);
2164                 return -ENODEV;
2165         }
2166
2167         se_sess = tv_nexus->tvn_se_sess;
2168         if (!se_sess) {
2169                 mutex_unlock(&tpg->tv_tpg_mutex);
2170                 return -ENODEV;
2171         }
2172
2173         if (tpg->tv_tpg_port_count != 0) {
2174                 mutex_unlock(&tpg->tv_tpg_mutex);
2175                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
2176                         " active TPG port count: %d\n",
2177                         tpg->tv_tpg_port_count);
2178                 return -EBUSY;
2179         }
2180
2181         if (tpg->tv_tpg_vhost_count != 0) {
2182                 mutex_unlock(&tpg->tv_tpg_mutex);
2183                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
2184                         " active TPG vhost count: %d\n",
2185                         tpg->tv_tpg_vhost_count);
2186                 return -EBUSY;
2187         }
2188
2189         pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated"
2190                 " %s Initiator Port: %s\n", vhost_scsi_dump_proto_id(tpg->tport),
2191                 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
2192
2193         /*
2194          * Release the SCSI I_T Nexus to the emulated vhost Target Port
2195          */
2196         target_remove_session(se_sess);
2197         tpg->tpg_nexus = NULL;
2198         mutex_unlock(&tpg->tv_tpg_mutex);
2199
2200         kfree(tv_nexus);
2201         return 0;
2202 }
2203
2204 static ssize_t vhost_scsi_tpg_nexus_show(struct config_item *item, char *page)
2205 {
2206         struct se_portal_group *se_tpg = to_tpg(item);
2207         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2208                                 struct vhost_scsi_tpg, se_tpg);
2209         struct vhost_scsi_nexus *tv_nexus;
2210         ssize_t ret;
2211
2212         mutex_lock(&tpg->tv_tpg_mutex);
2213         tv_nexus = tpg->tpg_nexus;
2214         if (!tv_nexus) {
2215                 mutex_unlock(&tpg->tv_tpg_mutex);
2216                 return -ENODEV;
2217         }
2218         ret = snprintf(page, PAGE_SIZE, "%s\n",
2219                         tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
2220         mutex_unlock(&tpg->tv_tpg_mutex);
2221
2222         return ret;
2223 }
2224
2225 static ssize_t vhost_scsi_tpg_nexus_store(struct config_item *item,
2226                 const char *page, size_t count)
2227 {
2228         struct se_portal_group *se_tpg = to_tpg(item);
2229         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2230                                 struct vhost_scsi_tpg, se_tpg);
2231         struct vhost_scsi_tport *tport_wwn = tpg->tport;
2232         unsigned char i_port[VHOST_SCSI_NAMELEN], *ptr, *port_ptr;
2233         int ret;
2234         /*
2235          * Shutdown the active I_T nexus if 'NULL' is passed..
2236          */
2237         if (!strncmp(page, "NULL", 4)) {
2238                 ret = vhost_scsi_drop_nexus(tpg);
2239                 return (!ret) ? count : ret;
2240         }
2241         /*
2242          * Otherwise make sure the passed virtual Initiator port WWN matches
2243          * the fabric protocol_id set in vhost_scsi_make_tport(), and call
2244          * vhost_scsi_make_nexus().
2245          */
2246         if (strlen(page) >= VHOST_SCSI_NAMELEN) {
2247                 pr_err("Emulated NAA Sas Address: %s, exceeds"
2248                                 " max: %d\n", page, VHOST_SCSI_NAMELEN);
2249                 return -EINVAL;
2250         }
2251         snprintf(&i_port[0], VHOST_SCSI_NAMELEN, "%s", page);
2252
2253         ptr = strstr(i_port, "naa.");
2254         if (ptr) {
2255                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
2256                         pr_err("Passed SAS Initiator Port %s does not"
2257                                 " match target port protoid: %s\n", i_port,
2258                                 vhost_scsi_dump_proto_id(tport_wwn));
2259                         return -EINVAL;
2260                 }
2261                 port_ptr = &i_port[0];
2262                 goto check_newline;
2263         }
2264         ptr = strstr(i_port, "fc.");
2265         if (ptr) {
2266                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
2267                         pr_err("Passed FCP Initiator Port %s does not"
2268                                 " match target port protoid: %s\n", i_port,
2269                                 vhost_scsi_dump_proto_id(tport_wwn));
2270                         return -EINVAL;
2271                 }
2272                 port_ptr = &i_port[3]; /* Skip over "fc." */
2273                 goto check_newline;
2274         }
2275         ptr = strstr(i_port, "iqn.");
2276         if (ptr) {
2277                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
2278                         pr_err("Passed iSCSI Initiator Port %s does not"
2279                                 " match target port protoid: %s\n", i_port,
2280                                 vhost_scsi_dump_proto_id(tport_wwn));
2281                         return -EINVAL;
2282                 }
2283                 port_ptr = &i_port[0];
2284                 goto check_newline;
2285         }
2286         pr_err("Unable to locate prefix for emulated Initiator Port:"
2287                         " %s\n", i_port);
2288         return -EINVAL;
2289         /*
2290          * Clear any trailing newline for the NAA WWN
2291          */
2292 check_newline:
2293         if (i_port[strlen(i_port)-1] == '\n')
2294                 i_port[strlen(i_port)-1] = '\0';
2295
2296         ret = vhost_scsi_make_nexus(tpg, port_ptr);
2297         if (ret < 0)
2298                 return ret;
2299
2300         return count;
2301 }
2302
2303 CONFIGFS_ATTR(vhost_scsi_tpg_, nexus);
2304
2305 static struct configfs_attribute *vhost_scsi_tpg_attrs[] = {
2306         &vhost_scsi_tpg_attr_nexus,
2307         NULL,
2308 };
2309
2310 static struct se_portal_group *
2311 vhost_scsi_make_tpg(struct se_wwn *wwn, const char *name)
2312 {
2313         struct vhost_scsi_tport *tport = container_of(wwn,
2314                         struct vhost_scsi_tport, tport_wwn);
2315
2316         struct vhost_scsi_tpg *tpg;
2317         u16 tpgt;
2318         int ret;
2319
2320         if (strstr(name, "tpgt_") != name)
2321                 return ERR_PTR(-EINVAL);
2322         if (kstrtou16(name + 5, 10, &tpgt) || tpgt >= VHOST_SCSI_MAX_TARGET)
2323                 return ERR_PTR(-EINVAL);
2324
2325         tpg = kzalloc(sizeof(*tpg), GFP_KERNEL);
2326         if (!tpg) {
2327                 pr_err("Unable to allocate struct vhost_scsi_tpg");
2328                 return ERR_PTR(-ENOMEM);
2329         }
2330         mutex_init(&tpg->tv_tpg_mutex);
2331         INIT_LIST_HEAD(&tpg->tv_tpg_list);
2332         INIT_LIST_HEAD(&tpg->tmf_queue);
2333         tpg->tport = tport;
2334         tpg->tport_tpgt = tpgt;
2335
2336         ret = core_tpg_register(wwn, &tpg->se_tpg, tport->tport_proto_id);
2337         if (ret < 0) {
2338                 kfree(tpg);
2339                 return NULL;
2340         }
2341         mutex_lock(&vhost_scsi_mutex);
2342         list_add_tail(&tpg->tv_tpg_list, &vhost_scsi_list);
2343         mutex_unlock(&vhost_scsi_mutex);
2344
2345         return &tpg->se_tpg;
2346 }
2347
2348 static void vhost_scsi_drop_tpg(struct se_portal_group *se_tpg)
2349 {
2350         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2351                                 struct vhost_scsi_tpg, se_tpg);
2352
2353         mutex_lock(&vhost_scsi_mutex);
2354         list_del(&tpg->tv_tpg_list);
2355         mutex_unlock(&vhost_scsi_mutex);
2356         /*
2357          * Release the virtual I_T Nexus for this vhost TPG
2358          */
2359         vhost_scsi_drop_nexus(tpg);
2360         /*
2361          * Deregister the se_tpg from TCM..
2362          */
2363         core_tpg_deregister(se_tpg);
2364         kfree(tpg);
2365 }
2366
2367 static struct se_wwn *
2368 vhost_scsi_make_tport(struct target_fabric_configfs *tf,
2369                      struct config_group *group,
2370                      const char *name)
2371 {
2372         struct vhost_scsi_tport *tport;
2373         char *ptr;
2374         u64 wwpn = 0;
2375         int off = 0;
2376
2377         /* if (vhost_scsi_parse_wwn(name, &wwpn, 1) < 0)
2378                 return ERR_PTR(-EINVAL); */
2379
2380         tport = kzalloc(sizeof(*tport), GFP_KERNEL);
2381         if (!tport) {
2382                 pr_err("Unable to allocate struct vhost_scsi_tport");
2383                 return ERR_PTR(-ENOMEM);
2384         }
2385         tport->tport_wwpn = wwpn;
2386         /*
2387          * Determine the emulated Protocol Identifier and Target Port Name
2388          * based on the incoming configfs directory name.
2389          */
2390         ptr = strstr(name, "naa.");
2391         if (ptr) {
2392                 tport->tport_proto_id = SCSI_PROTOCOL_SAS;
2393                 goto check_len;
2394         }
2395         ptr = strstr(name, "fc.");
2396         if (ptr) {
2397                 tport->tport_proto_id = SCSI_PROTOCOL_FCP;
2398                 off = 3; /* Skip over "fc." */
2399                 goto check_len;
2400         }
2401         ptr = strstr(name, "iqn.");
2402         if (ptr) {
2403                 tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
2404                 goto check_len;
2405         }
2406
2407         pr_err("Unable to locate prefix for emulated Target Port:"
2408                         " %s\n", name);
2409         kfree(tport);
2410         return ERR_PTR(-EINVAL);
2411
2412 check_len:
2413         if (strlen(name) >= VHOST_SCSI_NAMELEN) {
2414                 pr_err("Emulated %s Address: %s, exceeds"
2415                         " max: %d\n", name, vhost_scsi_dump_proto_id(tport),
2416                         VHOST_SCSI_NAMELEN);
2417                 kfree(tport);
2418                 return ERR_PTR(-EINVAL);
2419         }
2420         snprintf(&tport->tport_name[0], VHOST_SCSI_NAMELEN, "%s", &name[off]);
2421
2422         pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target"
2423                 " %s Address: %s\n", vhost_scsi_dump_proto_id(tport), name);
2424
2425         return &tport->tport_wwn;
2426 }
2427
2428 static void vhost_scsi_drop_tport(struct se_wwn *wwn)
2429 {
2430         struct vhost_scsi_tport *tport = container_of(wwn,
2431                                 struct vhost_scsi_tport, tport_wwn);
2432
2433         pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target"
2434                 " %s Address: %s\n", vhost_scsi_dump_proto_id(tport),
2435                 tport->tport_name);
2436
2437         kfree(tport);
2438 }
2439
2440 static ssize_t
2441 vhost_scsi_wwn_version_show(struct config_item *item, char *page)
2442 {
2443         return sprintf(page, "TCM_VHOST fabric module %s on %s/%s"
2444                 "on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
2445                 utsname()->machine);
2446 }
2447
2448 CONFIGFS_ATTR_RO(vhost_scsi_wwn_, version);
2449
2450 static struct configfs_attribute *vhost_scsi_wwn_attrs[] = {
2451         &vhost_scsi_wwn_attr_version,
2452         NULL,
2453 };
2454
2455 static const struct target_core_fabric_ops vhost_scsi_ops = {
2456         .module                         = THIS_MODULE,
2457         .fabric_name                    = "vhost",
2458         .max_data_sg_nents              = VHOST_SCSI_PREALLOC_SGLS,
2459         .tpg_get_wwn                    = vhost_scsi_get_fabric_wwn,
2460         .tpg_get_tag                    = vhost_scsi_get_tpgt,
2461         .tpg_check_demo_mode            = vhost_scsi_check_true,
2462         .tpg_check_demo_mode_cache      = vhost_scsi_check_true,
2463         .tpg_check_demo_mode_write_protect = vhost_scsi_check_false,
2464         .tpg_check_prod_mode_write_protect = vhost_scsi_check_false,
2465         .tpg_check_prot_fabric_only     = vhost_scsi_check_prot_fabric_only,
2466         .tpg_get_inst_index             = vhost_scsi_tpg_get_inst_index,
2467         .release_cmd                    = vhost_scsi_release_cmd,
2468         .check_stop_free                = vhost_scsi_check_stop_free,
2469         .sess_get_index                 = vhost_scsi_sess_get_index,
2470         .sess_get_initiator_sid         = NULL,
2471         .write_pending                  = vhost_scsi_write_pending,
2472         .set_default_node_attributes    = vhost_scsi_set_default_node_attrs,
2473         .get_cmd_state                  = vhost_scsi_get_cmd_state,
2474         .queue_data_in                  = vhost_scsi_queue_data_in,
2475         .queue_status                   = vhost_scsi_queue_status,
2476         .queue_tm_rsp                   = vhost_scsi_queue_tm_rsp,
2477         .aborted_task                   = vhost_scsi_aborted_task,
2478         /*
2479          * Setup callers for generic logic in target_core_fabric_configfs.c
2480          */
2481         .fabric_make_wwn                = vhost_scsi_make_tport,
2482         .fabric_drop_wwn                = vhost_scsi_drop_tport,
2483         .fabric_make_tpg                = vhost_scsi_make_tpg,
2484         .fabric_drop_tpg                = vhost_scsi_drop_tpg,
2485         .fabric_post_link               = vhost_scsi_port_link,
2486         .fabric_pre_unlink              = vhost_scsi_port_unlink,
2487
2488         .tfc_wwn_attrs                  = vhost_scsi_wwn_attrs,
2489         .tfc_tpg_base_attrs             = vhost_scsi_tpg_attrs,
2490         .tfc_tpg_attrib_attrs           = vhost_scsi_tpg_attrib_attrs,
2491 };
2492
2493 static int __init vhost_scsi_init(void)
2494 {
2495         int ret = -ENOMEM;
2496
2497         pr_debug("TCM_VHOST fabric module %s on %s/%s"
2498                 " on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
2499                 utsname()->machine);
2500
2501         ret = vhost_scsi_register();
2502         if (ret < 0)
2503                 goto out;
2504
2505         ret = target_register_template(&vhost_scsi_ops);
2506         if (ret < 0)
2507                 goto out_vhost_scsi_deregister;
2508
2509         return 0;
2510
2511 out_vhost_scsi_deregister:
2512         vhost_scsi_deregister();
2513 out:
2514         return ret;
2515 };
2516
2517 static void vhost_scsi_exit(void)
2518 {
2519         target_unregister_template(&vhost_scsi_ops);
2520         vhost_scsi_deregister();
2521 };
2522
2523 MODULE_DESCRIPTION("VHOST_SCSI series fabric driver");
2524 MODULE_ALIAS("tcm_vhost");
2525 MODULE_LICENSE("GPL");
2526 module_init(vhost_scsi_init);
2527 module_exit(vhost_scsi_exit);