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