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 <linux/blk_types.h>
  29 #include <linux/bio.h>
  30 #include <asm/unaligned.h>
  31 #include <scsi/scsi_common.h>
  32 #include <scsi/scsi_proto.h>
  33 #include <target/target_core_base.h>
  34 #include <target/target_core_fabric.h>
  35 #include <linux/vhost.h>
  36 #include <linux/virtio_scsi.h>
  37 #include <linux/llist.h>
  38 #include <linux/bitmap.h>
  39
  40 #include "vhost.h"
  41
  42 #define VHOST_SCSI_VERSION  "v0.1"
  43 #define VHOST_SCSI_NAMELEN 256
  44 #define VHOST_SCSI_MAX_CDB_SIZE 32
  45 #define VHOST_SCSI_PREALLOC_SGLS 2048
  46 #define VHOST_SCSI_PREALLOC_UPAGES 2048
  47 #define VHOST_SCSI_PREALLOC_PROT_SGLS 2048
  48
  49 /* Max number of requests before requeueing the job.
  50  * Using this limit prevents one virtqueue from starving others with
  51  * request.
  52  */
  53 #define VHOST_SCSI_WEIGHT 256
  54
  55 struct vhost_scsi_inflight {
  56         /* Wait for the flush operation to finish */
  57         struct completion comp;
  58         /* Refcount for the inflight reqs */
  59         struct kref kref;
  60 };
  61
  62 struct vhost_scsi_cmd {
  63         /* Descriptor from vhost_get_vq_desc() for virt_queue segment */
  64         int tvc_vq_desc;
  65         /* virtio-scsi initiator task attribute */
  66         int tvc_task_attr;
  67         /* virtio-scsi response incoming iovecs */
  68         int tvc_in_iovs;
  69         /* virtio-scsi initiator data direction */
  70         enum dma_data_direction tvc_data_direction;
  71         /* Expected data transfer length from virtio-scsi header */
  72         u32 tvc_exp_data_len;
  73         /* The Tag from include/linux/virtio_scsi.h:struct virtio_scsi_cmd_req */
  74         u64 tvc_tag;
  75         /* The number of scatterlists associated with this cmd */
  76         u32 tvc_sgl_count;
  77         u32 tvc_prot_sgl_count;
  78         /* Saved unpacked SCSI LUN for vhost_scsi_target_queue_cmd() */
  79         u32 tvc_lun;
  80         u32 copied_iov:1;
  81         const void *saved_iter_addr;
  82         struct iov_iter saved_iter;
  83         /* Pointer to the SGL formatted memory from virtio-scsi */
  84         struct scatterlist *tvc_sgl;
  85         struct scatterlist *tvc_prot_sgl;
  86         struct page **tvc_upages;
  87         /* Pointer to response header iovec */
  88         struct iovec *tvc_resp_iov;
  89         /* Pointer to vhost_scsi for our device */
  90         struct vhost_scsi *tvc_vhost;
  91         /* Pointer to vhost_virtqueue for the cmd */
  92         struct vhost_virtqueue *tvc_vq;
  93         /* Pointer to vhost nexus memory */
  94         struct vhost_scsi_nexus *tvc_nexus;
  95         /* The TCM I/O descriptor that is accessed via container_of() */
  96         struct se_cmd tvc_se_cmd;
  97         /* Copy of the incoming SCSI command descriptor block (CDB) */
  98         unsigned char tvc_cdb[VHOST_SCSI_MAX_CDB_SIZE];
  99         /* Sense buffer that will be mapped into outgoing status */
 100         unsigned char tvc_sense_buf[TRANSPORT_SENSE_BUFFER];
 101         /* Completed commands list, serviced from vhost worker thread */
 102         struct llist_node tvc_completion_list;
 103         /* Used to track inflight cmd */
 104         struct vhost_scsi_inflight *inflight;
 105 };
 106
 107 struct vhost_scsi_nexus {
 108         /* Pointer to TCM session for I_T Nexus */
 109         struct se_session *tvn_se_sess;
 110 };
 111
 112 struct vhost_scsi_tpg {
 113         /* Vhost port target portal group tag for TCM */
 114         u16 tport_tpgt;
 115         /* Used to track number of TPG Port/Lun Links wrt to explict I_T Nexus shutdown */
 116         int tv_tpg_port_count;
 117         /* Used for vhost_scsi device reference to tpg_nexus, protected by tv_tpg_mutex */
 118         int tv_tpg_vhost_count;
 119         /* Used for enabling T10-PI with legacy devices */
 120         int tv_fabric_prot_type;
 121         /* list for vhost_scsi_list */
 122         struct list_head tv_tpg_list;
 123         /* Used to protect access for tpg_nexus */
 124         struct mutex tv_tpg_mutex;
 125         /* Pointer to the TCM VHost I_T Nexus for this TPG endpoint */
 126         struct vhost_scsi_nexus *tpg_nexus;
 127         /* Pointer back to vhost_scsi_tport */
 128         struct vhost_scsi_tport *tport;
 129         /* Returned by vhost_scsi_make_tpg() */
 130         struct se_portal_group se_tpg;
 131         /* Pointer back to vhost_scsi, protected by tv_tpg_mutex */
 132         struct vhost_scsi *vhost_scsi;
 133 };
 134
 135 struct vhost_scsi_tport {
 136         /* SCSI protocol the tport is providing */
 137         u8 tport_proto_id;
 138         /* Binary World Wide unique Port Name for Vhost Target port */
 139         u64 tport_wwpn;
 140         /* ASCII formatted WWPN for Vhost Target port */
 141         char tport_name[VHOST_SCSI_NAMELEN];
 142         /* Returned by vhost_scsi_make_tport() */
 143         struct se_wwn tport_wwn;
 144 };
 145
 146 struct vhost_scsi_evt {
 147         /* event to be sent to guest */
 148         struct virtio_scsi_event event;
 149         /* event list, serviced from vhost worker thread */
 150         struct llist_node list;
 151 };
 152
 153 enum {
 154         VHOST_SCSI_VQ_CTL = 0,
 155         VHOST_SCSI_VQ_EVT = 1,
 156         VHOST_SCSI_VQ_IO = 2,
 157 };
 158
 159 /* Note: can't set VIRTIO_F_VERSION_1 yet, since that implies ANY_LAYOUT. */
 160 enum {
 161         VHOST_SCSI_FEATURES = VHOST_FEATURES | (1ULL << VIRTIO_SCSI_F_HOTPLUG) |
 162                                                (1ULL << VIRTIO_SCSI_F_T10_PI)
 163 };
 164
 165 #define VHOST_SCSI_MAX_TARGET   256
 166 #define VHOST_SCSI_MAX_IO_VQ    1024
 167 #define VHOST_SCSI_MAX_EVENT    128
 168
 169 static unsigned vhost_scsi_max_io_vqs = 128;
 170 module_param_named(max_io_vqs, vhost_scsi_max_io_vqs, uint, 0644);
 171 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.");
 172
 173 struct vhost_scsi_virtqueue {
 174         struct vhost_virtqueue vq;
 175         struct vhost_scsi *vs;
 176         /*
 177          * Reference counting for inflight reqs, used for flush operation. At
 178          * each time, one reference tracks new commands submitted, while we
 179          * wait for another one to reach 0.
 180          */
 181         struct vhost_scsi_inflight inflights[2];
 182         /*
 183          * Indicate current inflight in use, protected by vq->mutex.
 184          * Writers must also take dev mutex and flush under it.
 185          */
 186         int inflight_idx;
 187         struct vhost_scsi_cmd *scsi_cmds;
 188         struct sbitmap scsi_tags;
 189         int max_cmds;
 190
 191         struct vhost_work completion_work;
 192         struct llist_head completion_list;
 193 };
 194
 195 struct vhost_scsi {
 196         /* Protected by vhost_scsi->dev.mutex */
 197         struct vhost_scsi_tpg **vs_tpg;
 198         char vs_vhost_wwpn[TRANSPORT_IQN_LEN];
 199
 200         struct vhost_dev dev;
 201         struct vhost_scsi_virtqueue *vqs;
 202         struct vhost_scsi_inflight **old_inflight;
 203
 204         struct vhost_work vs_event_work; /* evt injection work item */
 205         struct llist_head vs_event_list; /* evt injection queue */
 206
 207         bool vs_events_missed; /* any missed events, protected by vq->mutex */
 208         int vs_events_nr; /* num of pending events, protected by vq->mutex */
 209 };
 210
 211 struct vhost_scsi_tmf {
 212         struct vhost_work vwork;
 213         struct work_struct flush_work;
 214         struct vhost_scsi *vhost;
 215         struct vhost_scsi_virtqueue *svq;
 216
 217         struct se_cmd se_cmd;
 218         u8 scsi_resp;
 219         struct vhost_scsi_inflight *inflight;
 220         struct iovec resp_iov;
 221         int in_iovs;
 222         int vq_desc;
 223 };
 224
 225 /*
 226  * Context for processing request and control queue operations.
 227  */
 228 struct vhost_scsi_ctx {
 229         int head;
 230         unsigned int out, in;
 231         size_t req_size, rsp_size;
 232         size_t out_size, in_size;
 233         u8 *target, *lunp;
 234         void *req;
 235         struct iov_iter out_iter;
 236 };
 237
 238 /*
 239  * Global mutex to protect vhost_scsi TPG list for vhost IOCTLs and LIO
 240  * configfs management operations.
 241  */
 242 static DEFINE_MUTEX(vhost_scsi_mutex);
 243 static LIST_HEAD(vhost_scsi_list);
 244
 245 static void vhost_scsi_done_inflight(struct kref *kref)
 246 {
 247         struct vhost_scsi_inflight *inflight;
 248
 249         inflight = container_of(kref, struct vhost_scsi_inflight, kref);
 250         complete(&inflight->comp);
 251 }
 252
 253 static void vhost_scsi_init_inflight(struct vhost_scsi *vs,
 254                                     struct vhost_scsi_inflight *old_inflight[])
 255 {
 256         struct vhost_scsi_inflight *new_inflight;
 257         struct vhost_virtqueue *vq;
 258         int idx, i;
 259
 260         for (i = 0; i < vs->dev.nvqs;  i++) {
 261                 vq = &vs->vqs[i].vq;
 262
 263                 mutex_lock(&vq->mutex);
 264
 265                 /* store old infight */
 266                 idx = vs->vqs[i].inflight_idx;
 267                 if (old_inflight)
 268                         old_inflight[i] = &vs->vqs[i].inflights[idx];
 269
 270                 /* setup new infight */
 271                 vs->vqs[i].inflight_idx = idx ^ 1;
 272                 new_inflight = &vs->vqs[i].inflights[idx ^ 1];
 273                 kref_init(&new_inflight->kref);
 274                 init_completion(&new_inflight->comp);
 275
 276                 mutex_unlock(&vq->mutex);
 277         }
 278 }
 279
 280 static struct vhost_scsi_inflight *
 281 vhost_scsi_get_inflight(struct vhost_virtqueue *vq)
 282 {
 283         struct vhost_scsi_inflight *inflight;
 284         struct vhost_scsi_virtqueue *svq;
 285
 286         svq = container_of(vq, struct vhost_scsi_virtqueue, vq);
 287         inflight = &svq->inflights[svq->inflight_idx];
 288         kref_get(&inflight->kref);
 289
 290         return inflight;
 291 }
 292
 293 static void vhost_scsi_put_inflight(struct vhost_scsi_inflight *inflight)
 294 {
 295         kref_put(&inflight->kref, vhost_scsi_done_inflight);
 296 }
 297
 298 static int vhost_scsi_check_true(struct se_portal_group *se_tpg)
 299 {
 300         return 1;
 301 }
 302
 303 static char *vhost_scsi_get_fabric_wwn(struct se_portal_group *se_tpg)
 304 {
 305         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 306                                 struct vhost_scsi_tpg, se_tpg);
 307         struct vhost_scsi_tport *tport = tpg->tport;
 308
 309         return &tport->tport_name[0];
 310 }
 311
 312 static u16 vhost_scsi_get_tpgt(struct se_portal_group *se_tpg)
 313 {
 314         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 315                                 struct vhost_scsi_tpg, se_tpg);
 316         return tpg->tport_tpgt;
 317 }
 318
 319 static int vhost_scsi_check_prot_fabric_only(struct se_portal_group *se_tpg)
 320 {
 321         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 322                                 struct vhost_scsi_tpg, se_tpg);
 323
 324         return tpg->tv_fabric_prot_type;
 325 }
 326
 327 static void vhost_scsi_release_cmd_res(struct se_cmd *se_cmd)
 328 {
 329         struct vhost_scsi_cmd *tv_cmd = container_of(se_cmd,
 330                                 struct vhost_scsi_cmd, tvc_se_cmd);
 331         struct vhost_scsi_virtqueue *svq = container_of(tv_cmd->tvc_vq,
 332                                 struct vhost_scsi_virtqueue, vq);
 333         struct vhost_scsi_inflight *inflight = tv_cmd->inflight;
 334         int i;
 335
 336         if (tv_cmd->tvc_sgl_count) {
 337                 for (i = 0; i < tv_cmd->tvc_sgl_count; i++) {
 338                         if (tv_cmd->copied_iov)
 339                                 __free_page(sg_page(&tv_cmd->tvc_sgl[i]));
 340                         else
 341                                 put_page(sg_page(&tv_cmd->tvc_sgl[i]));
 342                 }
 343                 kfree(tv_cmd->saved_iter_addr);
 344         }
 345         if (tv_cmd->tvc_prot_sgl_count) {
 346                 for (i = 0; i < tv_cmd->tvc_prot_sgl_count; i++)
 347                         put_page(sg_page(&tv_cmd->tvc_prot_sgl[i]));
 348         }
 349
 350         sbitmap_clear_bit(&svq->scsi_tags, se_cmd->map_tag);
 351         vhost_scsi_put_inflight(inflight);
 352 }
 353
 354 static void vhost_scsi_release_tmf_res(struct vhost_scsi_tmf *tmf)
 355 {
 356         struct vhost_scsi_inflight *inflight = tmf->inflight;
 357
 358         kfree(tmf);
 359         vhost_scsi_put_inflight(inflight);
 360 }
 361
 362 static void vhost_scsi_drop_cmds(struct vhost_scsi_virtqueue *svq)
 363 {
 364         struct vhost_scsi_cmd *cmd, *t;
 365         struct llist_node *llnode;
 366
 367         llnode = llist_del_all(&svq->completion_list);
 368         llist_for_each_entry_safe(cmd, t, llnode, tvc_completion_list)
 369                 vhost_scsi_release_cmd_res(&cmd->tvc_se_cmd);
 370 }
 371
 372 static void vhost_scsi_release_cmd(struct se_cmd *se_cmd)
 373 {
 374         if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB) {
 375                 struct vhost_scsi_tmf *tmf = container_of(se_cmd,
 376                                         struct vhost_scsi_tmf, se_cmd);
 377
 378                 schedule_work(&tmf->flush_work);
 379         } else {
 380                 struct vhost_scsi_cmd *cmd = container_of(se_cmd,
 381                                         struct vhost_scsi_cmd, tvc_se_cmd);
 382                 struct vhost_scsi_virtqueue *svq =  container_of(cmd->tvc_vq,
 383                                         struct vhost_scsi_virtqueue, vq);
 384
 385                 llist_add(&cmd->tvc_completion_list, &svq->completion_list);
 386                 if (!vhost_vq_work_queue(&svq->vq, &svq->completion_work))
 387                         vhost_scsi_drop_cmds(svq);
 388         }
 389 }
 390
 391 static int vhost_scsi_write_pending(struct se_cmd *se_cmd)
 392 {
 393         /* Go ahead and process the write immediately */
 394         target_execute_cmd(se_cmd);
 395         return 0;
 396 }
 397
 398 static int vhost_scsi_queue_data_in(struct se_cmd *se_cmd)
 399 {
 400         transport_generic_free_cmd(se_cmd, 0);
 401         return 0;
 402 }
 403
 404 static int vhost_scsi_queue_status(struct se_cmd *se_cmd)
 405 {
 406         transport_generic_free_cmd(se_cmd, 0);
 407         return 0;
 408 }
 409
 410 static void vhost_scsi_queue_tm_rsp(struct se_cmd *se_cmd)
 411 {
 412         struct vhost_scsi_tmf *tmf = container_of(se_cmd, struct vhost_scsi_tmf,
 413                                                   se_cmd);
 414
 415         tmf->scsi_resp = se_cmd->se_tmr_req->response;
 416         transport_generic_free_cmd(&tmf->se_cmd, 0);
 417 }
 418
 419 static void vhost_scsi_aborted_task(struct se_cmd *se_cmd)
 420 {
 421         return;
 422 }
 423
 424 static void vhost_scsi_free_evt(struct vhost_scsi *vs, struct vhost_scsi_evt *evt)
 425 {
 426         vs->vs_events_nr--;
 427         kfree(evt);
 428 }
 429
 430 static struct vhost_scsi_evt *
 431 vhost_scsi_allocate_evt(struct vhost_scsi *vs,
 432                        u32 event, u32 reason)
 433 {
 434         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 435         struct vhost_scsi_evt *evt;
 436
 437         if (vs->vs_events_nr > VHOST_SCSI_MAX_EVENT) {
 438                 vs->vs_events_missed = true;
 439                 return NULL;
 440         }
 441
 442         evt = kzalloc(sizeof(*evt), GFP_KERNEL);
 443         if (!evt) {
 444                 vq_err(vq, "Failed to allocate vhost_scsi_evt\n");
 445                 vs->vs_events_missed = true;
 446                 return NULL;
 447         }
 448
 449         evt->event.event = cpu_to_vhost32(vq, event);
 450         evt->event.reason = cpu_to_vhost32(vq, reason);
 451         vs->vs_events_nr++;
 452
 453         return evt;
 454 }
 455
 456 static int vhost_scsi_check_stop_free(struct se_cmd *se_cmd)
 457 {
 458         return target_put_sess_cmd(se_cmd);
 459 }
 460
 461 static void
 462 vhost_scsi_do_evt_work(struct vhost_scsi *vs, struct vhost_scsi_evt *evt)
 463 {
 464         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 465         struct virtio_scsi_event *event = &evt->event;
 466         struct virtio_scsi_event __user *eventp;
 467         unsigned out, in;
 468         int head, ret;
 469
 470         if (!vhost_vq_get_backend(vq)) {
 471                 vs->vs_events_missed = true;
 472                 return;
 473         }
 474
 475 again:
 476         vhost_disable_notify(&vs->dev, vq);
 477         head = vhost_get_vq_desc(vq, vq->iov,
 478                         ARRAY_SIZE(vq->iov), &out, &in,
 479                         NULL, NULL);
 480         if (head < 0) {
 481                 vs->vs_events_missed = true;
 482                 return;
 483         }
 484         if (head == vq->num) {
 485                 if (vhost_enable_notify(&vs->dev, vq))
 486                         goto again;
 487                 vs->vs_events_missed = true;
 488                 return;
 489         }
 490
 491         if ((vq->iov[out].iov_len != sizeof(struct virtio_scsi_event))) {
 492                 vq_err(vq, "Expecting virtio_scsi_event, got %zu bytes\n",
 493                                 vq->iov[out].iov_len);
 494                 vs->vs_events_missed = true;
 495                 return;
 496         }
 497
 498         if (vs->vs_events_missed) {
 499                 event->event |= cpu_to_vhost32(vq, VIRTIO_SCSI_T_EVENTS_MISSED);
 500                 vs->vs_events_missed = false;
 501         }
 502
 503         eventp = vq->iov[out].iov_base;
 504         ret = __copy_to_user(eventp, event, sizeof(*event));
 505         if (!ret)
 506                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 507         else
 508                 vq_err(vq, "Faulted on vhost_scsi_send_event\n");
 509 }
 510
 511 static void vhost_scsi_complete_events(struct vhost_scsi *vs, bool drop)
 512 {
 513         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 514         struct vhost_scsi_evt *evt, *t;
 515         struct llist_node *llnode;
 516
 517         mutex_lock(&vq->mutex);
 518         llnode = llist_del_all(&vs->vs_event_list);
 519         llist_for_each_entry_safe(evt, t, llnode, list) {
 520                 if (!drop)
 521                         vhost_scsi_do_evt_work(vs, evt);
 522                 vhost_scsi_free_evt(vs, evt);
 523         }
 524         mutex_unlock(&vq->mutex);
 525 }
 526
 527 static void vhost_scsi_evt_work(struct vhost_work *work)
 528 {
 529         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 530                                              vs_event_work);
 531         vhost_scsi_complete_events(vs, false);
 532 }
 533
 534 static int vhost_scsi_copy_sgl_to_iov(struct vhost_scsi_cmd *cmd)
 535 {
 536         struct iov_iter *iter = &cmd->saved_iter;
 537         struct scatterlist *sg = cmd->tvc_sgl;
 538         struct page *page;
 539         size_t len;
 540         int i;
 541
 542         for (i = 0; i < cmd->tvc_sgl_count; i++) {
 543                 page = sg_page(&sg[i]);
 544                 len = sg[i].length;
 545
 546                 if (copy_page_to_iter(page, 0, len, iter) != len) {
 547                         pr_err("Could not copy data while handling misaligned cmd. Error %zu\n",
 548                                len);
 549                         return -1;
 550                 }
 551         }
 552
 553         return 0;
 554 }
 555
 556 /* Fill in status and signal that we are done processing this command
 557  *
 558  * This is scheduled in the vhost work queue so we are called with the owner
 559  * process mm and can access the vring.
 560  */
 561 static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
 562 {
 563         struct vhost_scsi_virtqueue *svq = container_of(work,
 564                                 struct vhost_scsi_virtqueue, completion_work);
 565         struct virtio_scsi_cmd_resp v_rsp;
 566         struct vhost_scsi_cmd *cmd, *t;
 567         struct llist_node *llnode;
 568         struct se_cmd *se_cmd;
 569         struct iov_iter iov_iter;
 570         bool signal = false;
 571         int ret;
 572
 573         llnode = llist_del_all(&svq->completion_list);
 574         llist_for_each_entry_safe(cmd, t, llnode, tvc_completion_list) {
 575                 se_cmd = &cmd->tvc_se_cmd;
 576
 577                 pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__,
 578                         cmd, se_cmd->residual_count, se_cmd->scsi_status);
 579                 memset(&v_rsp, 0, sizeof(v_rsp));
 580
 581                 if (cmd->saved_iter_addr && vhost_scsi_copy_sgl_to_iov(cmd)) {
 582                         v_rsp.response = VIRTIO_SCSI_S_BAD_TARGET;
 583                 } else {
 584                         v_rsp.resid = cpu_to_vhost32(cmd->tvc_vq,
 585                                                      se_cmd->residual_count);
 586                         /* TODO is status_qualifier field needed? */
 587                         v_rsp.status = se_cmd->scsi_status;
 588                         v_rsp.sense_len = cpu_to_vhost32(cmd->tvc_vq,
 589                                                          se_cmd->scsi_sense_length);
 590                         memcpy(v_rsp.sense, cmd->tvc_sense_buf,
 591                                se_cmd->scsi_sense_length);
 592                 }
 593
 594                 iov_iter_init(&iov_iter, ITER_DEST, cmd->tvc_resp_iov,
 595                               cmd->tvc_in_iovs, sizeof(v_rsp));
 596                 ret = copy_to_iter(&v_rsp, sizeof(v_rsp), &iov_iter);
 597                 if (likely(ret == sizeof(v_rsp))) {
 598                         signal = true;
 599
 600                         vhost_add_used(cmd->tvc_vq, cmd->tvc_vq_desc, 0);
 601                 } else
 602                         pr_err("Faulted on virtio_scsi_cmd_resp\n");
 603
 604                 vhost_scsi_release_cmd_res(se_cmd);
 605         }
 606
 607         if (signal)
 608                 vhost_signal(&svq->vs->dev, &svq->vq);
 609 }
 610
 611 static struct vhost_scsi_cmd *
 612 vhost_scsi_get_cmd(struct vhost_virtqueue *vq, struct vhost_scsi_tpg *tpg,
 613                    unsigned char *cdb, u64 scsi_tag, u16 lun, u8 task_attr,
 614                    u32 exp_data_len, int data_direction)
 615 {
 616         struct vhost_scsi_virtqueue *svq = container_of(vq,
 617                                         struct vhost_scsi_virtqueue, vq);
 618         struct vhost_scsi_cmd *cmd;
 619         struct vhost_scsi_nexus *tv_nexus;
 620         struct scatterlist *sg, *prot_sg;
 621         struct iovec *tvc_resp_iov;
 622         struct page **pages;
 623         int tag;
 624
 625         tv_nexus = tpg->tpg_nexus;
 626         if (!tv_nexus) {
 627                 pr_err("Unable to locate active struct vhost_scsi_nexus\n");
 628                 return ERR_PTR(-EIO);
 629         }
 630
 631         tag = sbitmap_get(&svq->scsi_tags);
 632         if (tag < 0) {
 633                 pr_err("Unable to obtain tag for vhost_scsi_cmd\n");
 634                 return ERR_PTR(-ENOMEM);
 635         }
 636
 637         cmd = &svq->scsi_cmds[tag];
 638         sg = cmd->tvc_sgl;
 639         prot_sg = cmd->tvc_prot_sgl;
 640         pages = cmd->tvc_upages;
 641         tvc_resp_iov = cmd->tvc_resp_iov;
 642         memset(cmd, 0, sizeof(*cmd));
 643         cmd->tvc_sgl = sg;
 644         cmd->tvc_prot_sgl = prot_sg;
 645         cmd->tvc_upages = pages;
 646         cmd->tvc_se_cmd.map_tag = tag;
 647         cmd->tvc_tag = scsi_tag;
 648         cmd->tvc_lun = lun;
 649         cmd->tvc_task_attr = task_attr;
 650         cmd->tvc_exp_data_len = exp_data_len;
 651         cmd->tvc_data_direction = data_direction;
 652         cmd->tvc_nexus = tv_nexus;
 653         cmd->inflight = vhost_scsi_get_inflight(vq);
 654         cmd->tvc_resp_iov = tvc_resp_iov;
 655
 656         memcpy(cmd->tvc_cdb, cdb, VHOST_SCSI_MAX_CDB_SIZE);
 657
 658         return cmd;
 659 }
 660
 661 /*
 662  * Map a user memory range into a scatterlist
 663  *
 664  * Returns the number of scatterlist entries used or -errno on error.
 665  */
 666 static int
 667 vhost_scsi_map_to_sgl(struct vhost_scsi_cmd *cmd,
 668                       struct iov_iter *iter,
 669                       struct scatterlist *sgl,
 670                       bool is_prot)
 671 {
 672         struct page **pages = cmd->tvc_upages;
 673         struct scatterlist *sg = sgl;
 674         ssize_t bytes, mapped_bytes;
 675         size_t offset, mapped_offset;
 676         unsigned int npages = 0;
 677
 678         bytes = iov_iter_get_pages2(iter, pages, LONG_MAX,
 679                                 VHOST_SCSI_PREALLOC_UPAGES, &offset);
 680         /* No pages were pinned */
 681         if (bytes <= 0)
 682                 return bytes < 0 ? bytes : -EFAULT;
 683
 684         mapped_bytes = bytes;
 685         mapped_offset = offset;
 686
 687         while (bytes) {
 688                 unsigned n = min_t(unsigned, PAGE_SIZE - offset, bytes);
 689                 /*
 690                  * The block layer requires bios/requests to be a multiple of
 691                  * 512 bytes, but Windows can send us vecs that are misaligned.
 692                  * This can result in bios and later requests with misaligned
 693                  * sizes if we have to break up a cmd/scatterlist into multiple
 694                  * bios.
 695                  *
 696                  * We currently only break up a command into multiple bios if
 697                  * we hit the vec/seg limit, so check if our sgl_count is
 698                  * greater than the max and if a vec in the cmd has a
 699                  * misaligned offset/size.
 700                  */
 701                 if (!is_prot &&
 702                     (offset & (SECTOR_SIZE - 1) || n & (SECTOR_SIZE - 1)) &&
 703                     cmd->tvc_sgl_count > BIO_MAX_VECS) {
 704                         WARN_ONCE(true,
 705                                   "vhost-scsi detected misaligned IO. Performance may be degraded.");
 706                         goto revert_iter_get_pages;
 707                 }
 708
 709                 sg_set_page(sg++, pages[npages++], n, offset);
 710                 bytes -= n;
 711                 offset = 0;
 712         }
 713
 714         return npages;
 715
 716 revert_iter_get_pages:
 717         iov_iter_revert(iter, mapped_bytes);
 718
 719         npages = 0;
 720         while (mapped_bytes) {
 721                 unsigned int n = min_t(unsigned int, PAGE_SIZE - mapped_offset,
 722                                        mapped_bytes);
 723
 724                 put_page(pages[npages++]);
 725
 726                 mapped_bytes -= n;
 727                 mapped_offset = 0;
 728         }
 729
 730         return -EINVAL;
 731 }
 732
 733 static int
 734 vhost_scsi_calc_sgls(struct iov_iter *iter, size_t bytes, int max_sgls)
 735 {
 736         int sgl_count = 0;
 737
 738         if (!iter || !iter_iov(iter)) {
 739                 pr_err("%s: iter->iov is NULL, but expected bytes: %zu"
 740                        " present\n", __func__, bytes);
 741                 return -EINVAL;
 742         }
 743
 744         sgl_count = iov_iter_npages(iter, 0xffff);
 745         if (sgl_count > max_sgls) {
 746                 pr_err("%s: requested sgl_count: %d exceeds pre-allocated"
 747                        " max_sgls: %d\n", __func__, sgl_count, max_sgls);
 748                 return -EINVAL;
 749         }
 750         return sgl_count;
 751 }
 752
 753 static int
 754 vhost_scsi_copy_iov_to_sgl(struct vhost_scsi_cmd *cmd, struct iov_iter *iter,
 755                            struct scatterlist *sg, int sg_count)
 756 {
 757         size_t len = iov_iter_count(iter);
 758         unsigned int nbytes = 0;
 759         struct page *page;
 760         int i;
 761
 762         if (cmd->tvc_data_direction == DMA_FROM_DEVICE) {
 763                 cmd->saved_iter_addr = dup_iter(&cmd->saved_iter, iter,
 764                                                 GFP_KERNEL);
 765                 if (!cmd->saved_iter_addr)
 766                         return -ENOMEM;
 767         }
 768
 769         for (i = 0; i < sg_count; i++) {
 770                 page = alloc_page(GFP_KERNEL);
 771                 if (!page) {
 772                         i--;
 773                         goto err;
 774                 }
 775
 776                 nbytes = min_t(unsigned int, PAGE_SIZE, len);
 777                 sg_set_page(&sg[i], page, nbytes, 0);
 778
 779                 if (cmd->tvc_data_direction == DMA_TO_DEVICE &&
 780                     copy_page_from_iter(page, 0, nbytes, iter) != nbytes)
 781                         goto err;
 782
 783                 len -= nbytes;
 784         }
 785
 786         cmd->copied_iov = 1;
 787         return 0;
 788
 789 err:
 790         pr_err("Could not read %u bytes while handling misaligned cmd\n",
 791                nbytes);
 792
 793         for (; i >= 0; i--)
 794                 __free_page(sg_page(&sg[i]));
 795         kfree(cmd->saved_iter_addr);
 796         return -ENOMEM;
 797 }
 798
 799 static int
 800 vhost_scsi_map_iov_to_sgl(struct vhost_scsi_cmd *cmd, struct iov_iter *iter,
 801                           struct scatterlist *sg, int sg_count, bool is_prot)
 802 {
 803         struct scatterlist *p = sg;
 804         size_t revert_bytes;
 805         int ret;
 806
 807         while (iov_iter_count(iter)) {
 808                 ret = vhost_scsi_map_to_sgl(cmd, iter, sg, is_prot);
 809                 if (ret < 0) {
 810                         revert_bytes = 0;
 811
 812                         while (p < sg) {
 813                                 struct page *page = sg_page(p);
 814
 815                                 if (page) {
 816                                         put_page(page);
 817                                         revert_bytes += p->length;
 818                                 }
 819                                 p++;
 820                         }
 821
 822                         iov_iter_revert(iter, revert_bytes);
 823                         return ret;
 824                 }
 825                 sg += ret;
 826         }
 827
 828         return 0;
 829 }
 830
 831 static int
 832 vhost_scsi_mapal(struct vhost_scsi_cmd *cmd,
 833                  size_t prot_bytes, struct iov_iter *prot_iter,
 834                  size_t data_bytes, struct iov_iter *data_iter)
 835 {
 836         int sgl_count, ret;
 837
 838         if (prot_bytes) {
 839                 sgl_count = vhost_scsi_calc_sgls(prot_iter, prot_bytes,
 840                                                  VHOST_SCSI_PREALLOC_PROT_SGLS);
 841                 if (sgl_count < 0)
 842                         return sgl_count;
 843
 844                 sg_init_table(cmd->tvc_prot_sgl, sgl_count);
 845                 cmd->tvc_prot_sgl_count = sgl_count;
 846                 pr_debug("%s prot_sg %p prot_sgl_count %u\n", __func__,
 847                          cmd->tvc_prot_sgl, cmd->tvc_prot_sgl_count);
 848
 849                 ret = vhost_scsi_map_iov_to_sgl(cmd, prot_iter,
 850                                                 cmd->tvc_prot_sgl,
 851                                                 cmd->tvc_prot_sgl_count, true);
 852                 if (ret < 0) {
 853                         cmd->tvc_prot_sgl_count = 0;
 854                         return ret;
 855                 }
 856         }
 857         sgl_count = vhost_scsi_calc_sgls(data_iter, data_bytes,
 858                                          VHOST_SCSI_PREALLOC_SGLS);
 859         if (sgl_count < 0)
 860                 return sgl_count;
 861
 862         sg_init_table(cmd->tvc_sgl, sgl_count);
 863         cmd->tvc_sgl_count = sgl_count;
 864         pr_debug("%s data_sg %p data_sgl_count %u\n", __func__,
 865                   cmd->tvc_sgl, cmd->tvc_sgl_count);
 866
 867         ret = vhost_scsi_map_iov_to_sgl(cmd, data_iter, cmd->tvc_sgl,
 868                                         cmd->tvc_sgl_count, false);
 869         if (ret == -EINVAL) {
 870                 sg_init_table(cmd->tvc_sgl, cmd->tvc_sgl_count);
 871                 ret = vhost_scsi_copy_iov_to_sgl(cmd, data_iter, cmd->tvc_sgl,
 872                                                  cmd->tvc_sgl_count);
 873         }
 874
 875         if (ret < 0) {
 876                 cmd->tvc_sgl_count = 0;
 877                 return ret;
 878         }
 879         return 0;
 880 }
 881
 882 static int vhost_scsi_to_tcm_attr(int attr)
 883 {
 884         switch (attr) {
 885         case VIRTIO_SCSI_S_SIMPLE:
 886                 return TCM_SIMPLE_TAG;
 887         case VIRTIO_SCSI_S_ORDERED:
 888                 return TCM_ORDERED_TAG;
 889         case VIRTIO_SCSI_S_HEAD:
 890                 return TCM_HEAD_TAG;
 891         case VIRTIO_SCSI_S_ACA:
 892                 return TCM_ACA_TAG;
 893         default:
 894                 break;
 895         }
 896         return TCM_SIMPLE_TAG;
 897 }
 898
 899 static void vhost_scsi_target_queue_cmd(struct vhost_scsi_cmd *cmd)
 900 {
 901         struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
 902         struct vhost_scsi_nexus *tv_nexus;
 903         struct scatterlist *sg_ptr, *sg_prot_ptr = NULL;
 904
 905         /* FIXME: BIDI operation */
 906         if (cmd->tvc_sgl_count) {
 907                 sg_ptr = cmd->tvc_sgl;
 908
 909                 if (cmd->tvc_prot_sgl_count)
 910                         sg_prot_ptr = cmd->tvc_prot_sgl;
 911                 else
 912                         se_cmd->prot_pto = true;
 913         } else {
 914                 sg_ptr = NULL;
 915         }
 916         tv_nexus = cmd->tvc_nexus;
 917
 918         se_cmd->tag = 0;
 919         target_init_cmd(se_cmd, tv_nexus->tvn_se_sess, &cmd->tvc_sense_buf[0],
 920                         cmd->tvc_lun, cmd->tvc_exp_data_len,
 921                         vhost_scsi_to_tcm_attr(cmd->tvc_task_attr),
 922                         cmd->tvc_data_direction, TARGET_SCF_ACK_KREF);
 923
 924         if (target_submit_prep(se_cmd, cmd->tvc_cdb, sg_ptr,
 925                                cmd->tvc_sgl_count, NULL, 0, sg_prot_ptr,
 926                                cmd->tvc_prot_sgl_count, GFP_KERNEL))
 927                 return;
 928
 929         target_submit(se_cmd);
 930 }
 931
 932 static void
 933 vhost_scsi_send_bad_target(struct vhost_scsi *vs,
 934                            struct vhost_virtqueue *vq,
 935                            int head, unsigned out)
 936 {
 937         struct virtio_scsi_cmd_resp __user *resp;
 938         struct virtio_scsi_cmd_resp rsp;
 939         int ret;
 940
 941         memset(&rsp, 0, sizeof(rsp));
 942         rsp.response = VIRTIO_SCSI_S_BAD_TARGET;
 943         resp = vq->iov[out].iov_base;
 944         ret = __copy_to_user(resp, &rsp, sizeof(rsp));
 945         if (!ret)
 946                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 947         else
 948                 pr_err("Faulted on virtio_scsi_cmd_resp\n");
 949 }
 950
 951 static int
 952 vhost_scsi_get_desc(struct vhost_scsi *vs, struct vhost_virtqueue *vq,
 953                     struct vhost_scsi_ctx *vc)
 954 {
 955         int ret = -ENXIO;
 956
 957         vc->head = vhost_get_vq_desc(vq, vq->iov,
 958                                      ARRAY_SIZE(vq->iov), &vc->out, &vc->in,
 959                                      NULL, NULL);
 960
 961         pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n",
 962                  vc->head, vc->out, vc->in);
 963
 964         /* On error, stop handling until the next kick. */
 965         if (unlikely(vc->head < 0))
 966                 goto done;
 967
 968         /* Nothing new?  Wait for eventfd to tell us they refilled. */
 969         if (vc->head == vq->num) {
 970                 if (unlikely(vhost_enable_notify(&vs->dev, vq))) {
 971                         vhost_disable_notify(&vs->dev, vq);
 972                         ret = -EAGAIN;
 973                 }
 974                 goto done;
 975         }
 976
 977         /*
 978          * Get the size of request and response buffers.
 979          * FIXME: Not correct for BIDI operation
 980          */
 981         vc->out_size = iov_length(vq->iov, vc->out);
 982         vc->in_size = iov_length(&vq->iov[vc->out], vc->in);
 983
 984         /*
 985          * Copy over the virtio-scsi request header, which for a
 986          * ANY_LAYOUT enabled guest may span multiple iovecs, or a
 987          * single iovec may contain both the header + outgoing
 988          * WRITE payloads.
 989          *
 990          * copy_from_iter() will advance out_iter, so that it will
 991          * point at the start of the outgoing WRITE payload, if
 992          * DMA_TO_DEVICE is set.
 993          */
 994         iov_iter_init(&vc->out_iter, ITER_SOURCE, vq->iov, vc->out, vc->out_size);
 995         ret = 0;
 996
 997 done:
 998         return ret;
 999 }
1000
1001 static int
1002 vhost_scsi_chk_size(struct vhost_virtqueue *vq, struct vhost_scsi_ctx *vc)
1003 {
1004         if (unlikely(vc->in_size < vc->rsp_size)) {
1005                 vq_err(vq,
1006                        "Response buf too small, need min %zu bytes got %zu",
1007                        vc->rsp_size, vc->in_size);
1008                 return -EINVAL;
1009         } else if (unlikely(vc->out_size < vc->req_size)) {
1010                 vq_err(vq,
1011                        "Request buf too small, need min %zu bytes got %zu",
1012                        vc->req_size, vc->out_size);
1013                 return -EIO;
1014         }
1015
1016         return 0;
1017 }
1018
1019 static int
1020 vhost_scsi_get_req(struct vhost_virtqueue *vq, struct vhost_scsi_ctx *vc,
1021                    struct vhost_scsi_tpg **tpgp)
1022 {
1023         int ret = -EIO;
1024
1025         if (unlikely(!copy_from_iter_full(vc->req, vc->req_size,
1026                                           &vc->out_iter))) {
1027                 vq_err(vq, "Faulted on copy_from_iter_full\n");
1028         } else if (unlikely(*vc->lunp != 1)) {
1029                 /* virtio-scsi spec requires byte 0 of the lun to be 1 */
1030                 vq_err(vq, "Illegal virtio-scsi lun: %u\n", *vc->lunp);
1031         } else {
1032                 struct vhost_scsi_tpg **vs_tpg, *tpg;
1033
1034                 vs_tpg = vhost_vq_get_backend(vq);      /* validated at handler entry */
1035
1036                 tpg = READ_ONCE(vs_tpg[*vc->target]);
1037                 if (unlikely(!tpg)) {
1038                         vq_err(vq, "Target 0x%x does not exist\n", *vc->target);
1039                 } else {
1040                         if (tpgp)
1041                                 *tpgp = tpg;
1042                         ret = 0;
1043                 }
1044         }
1045
1046         return ret;
1047 }
1048
1049 static u16 vhost_buf_to_lun(u8 *lun_buf)
1050 {
1051         return ((lun_buf[2] << 8) | lun_buf[3]) & 0x3FFF;
1052 }
1053
1054 static void
1055 vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
1056 {
1057         struct vhost_scsi_tpg **vs_tpg, *tpg;
1058         struct virtio_scsi_cmd_req v_req;
1059         struct virtio_scsi_cmd_req_pi v_req_pi;
1060         struct vhost_scsi_ctx vc;
1061         struct vhost_scsi_cmd *cmd;
1062         struct iov_iter in_iter, prot_iter, data_iter;
1063         u64 tag;
1064         u32 exp_data_len, data_direction;
1065         int ret, prot_bytes, i, c = 0;
1066         u16 lun;
1067         u8 task_attr;
1068         bool t10_pi = vhost_has_feature(vq, VIRTIO_SCSI_F_T10_PI);
1069         void *cdb;
1070
1071         mutex_lock(&vq->mutex);
1072         /*
1073          * We can handle the vq only after the endpoint is setup by calling the
1074          * VHOST_SCSI_SET_ENDPOINT ioctl.
1075          */
1076         vs_tpg = vhost_vq_get_backend(vq);
1077         if (!vs_tpg)
1078                 goto out;
1079
1080         memset(&vc, 0, sizeof(vc));
1081         vc.rsp_size = sizeof(struct virtio_scsi_cmd_resp);
1082
1083         vhost_disable_notify(&vs->dev, vq);
1084
1085         do {
1086                 ret = vhost_scsi_get_desc(vs, vq, &vc);
1087                 if (ret)
1088                         goto err;
1089
1090                 /*
1091                  * Setup pointers and values based upon different virtio-scsi
1092                  * request header if T10_PI is enabled in KVM guest.
1093                  */
1094                 if (t10_pi) {
1095                         vc.req = &v_req_pi;
1096                         vc.req_size = sizeof(v_req_pi);
1097                         vc.lunp = &v_req_pi.lun[0];
1098                         vc.target = &v_req_pi.lun[1];
1099                 } else {
1100                         vc.req = &v_req;
1101                         vc.req_size = sizeof(v_req);
1102                         vc.lunp = &v_req.lun[0];
1103                         vc.target = &v_req.lun[1];
1104                 }
1105
1106                 /*
1107                  * Validate the size of request and response buffers.
1108                  * Check for a sane response buffer so we can report
1109                  * early errors back to the guest.
1110                  */
1111                 ret = vhost_scsi_chk_size(vq, &vc);
1112                 if (ret)
1113                         goto err;
1114
1115                 ret = vhost_scsi_get_req(vq, &vc, &tpg);
1116                 if (ret)
1117                         goto err;
1118
1119                 ret = -EIO;     /* bad target on any error from here on */
1120
1121                 /*
1122                  * Determine data_direction by calculating the total outgoing
1123                  * iovec sizes + incoming iovec sizes vs. virtio-scsi request +
1124                  * response headers respectively.
1125                  *
1126                  * For DMA_TO_DEVICE this is out_iter, which is already pointing
1127                  * to the right place.
1128                  *
1129                  * For DMA_FROM_DEVICE, the iovec will be just past the end
1130                  * of the virtio-scsi response header in either the same
1131                  * or immediately following iovec.
1132                  *
1133                  * Any associated T10_PI bytes for the outgoing / incoming
1134                  * payloads are included in calculation of exp_data_len here.
1135                  */
1136                 prot_bytes = 0;
1137
1138                 if (vc.out_size > vc.req_size) {
1139                         data_direction = DMA_TO_DEVICE;
1140                         exp_data_len = vc.out_size - vc.req_size;
1141                         data_iter = vc.out_iter;
1142                 } else if (vc.in_size > vc.rsp_size) {
1143                         data_direction = DMA_FROM_DEVICE;
1144                         exp_data_len = vc.in_size - vc.rsp_size;
1145
1146                         iov_iter_init(&in_iter, ITER_DEST, &vq->iov[vc.out], vc.in,
1147                                       vc.rsp_size + exp_data_len);
1148                         iov_iter_advance(&in_iter, vc.rsp_size);
1149                         data_iter = in_iter;
1150                 } else {
1151                         data_direction = DMA_NONE;
1152                         exp_data_len = 0;
1153                 }
1154                 /*
1155                  * If T10_PI header + payload is present, setup prot_iter values
1156                  * and recalculate data_iter for vhost_scsi_mapal() mapping to
1157                  * host scatterlists via get_user_pages_fast().
1158                  */
1159                 if (t10_pi) {
1160                         if (v_req_pi.pi_bytesout) {
1161                                 if (data_direction != DMA_TO_DEVICE) {
1162                                         vq_err(vq, "Received non zero pi_bytesout,"
1163                                                 " but wrong data_direction\n");
1164                                         goto err;
1165                                 }
1166                                 prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesout);
1167                         } else if (v_req_pi.pi_bytesin) {
1168                                 if (data_direction != DMA_FROM_DEVICE) {
1169                                         vq_err(vq, "Received non zero pi_bytesin,"
1170                                                 " but wrong data_direction\n");
1171                                         goto err;
1172                                 }
1173                                 prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesin);
1174                         }
1175                         /*
1176                          * Set prot_iter to data_iter and truncate it to
1177                          * prot_bytes, and advance data_iter past any
1178                          * preceding prot_bytes that may be present.
1179                          *
1180                          * Also fix up the exp_data_len to reflect only the
1181                          * actual data payload length.
1182                          */
1183                         if (prot_bytes) {
1184                                 exp_data_len -= prot_bytes;
1185                                 prot_iter = data_iter;
1186                                 iov_iter_truncate(&prot_iter, prot_bytes);
1187                                 iov_iter_advance(&data_iter, prot_bytes);
1188                         }
1189                         tag = vhost64_to_cpu(vq, v_req_pi.tag);
1190                         task_attr = v_req_pi.task_attr;
1191                         cdb = &v_req_pi.cdb[0];
1192                         lun = vhost_buf_to_lun(v_req_pi.lun);
1193                 } else {
1194                         tag = vhost64_to_cpu(vq, v_req.tag);
1195                         task_attr = v_req.task_attr;
1196                         cdb = &v_req.cdb[0];
1197                         lun = vhost_buf_to_lun(v_req.lun);
1198                 }
1199                 /*
1200                  * Check that the received CDB size does not exceeded our
1201                  * hardcoded max for vhost-scsi, then get a pre-allocated
1202                  * cmd descriptor for the new virtio-scsi tag.
1203                  *
1204                  * TODO what if cdb was too small for varlen cdb header?
1205                  */
1206                 if (unlikely(scsi_command_size(cdb) > VHOST_SCSI_MAX_CDB_SIZE)) {
1207                         vq_err(vq, "Received SCSI CDB with command_size: %d that"
1208                                 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1209                                 scsi_command_size(cdb), VHOST_SCSI_MAX_CDB_SIZE);
1210                                 goto err;
1211                 }
1212                 cmd = vhost_scsi_get_cmd(vq, tpg, cdb, tag, lun, task_attr,
1213                                          exp_data_len + prot_bytes,
1214                                          data_direction);
1215                 if (IS_ERR(cmd)) {
1216                         vq_err(vq, "vhost_scsi_get_cmd failed %ld\n",
1217                                PTR_ERR(cmd));
1218                         goto err;
1219                 }
1220                 cmd->tvc_vhost = vs;
1221                 cmd->tvc_vq = vq;
1222                 for (i = 0; i < vc.in ; i++)
1223                         cmd->tvc_resp_iov[i] = vq->iov[vc.out + i];
1224                 cmd->tvc_in_iovs = vc.in;
1225
1226                 pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n",
1227                          cmd->tvc_cdb[0], cmd->tvc_lun);
1228                 pr_debug("cmd: %p exp_data_len: %d, prot_bytes: %d data_direction:"
1229                          " %d\n", cmd, exp_data_len, prot_bytes, data_direction);
1230
1231                 if (data_direction != DMA_NONE) {
1232                         if (unlikely(vhost_scsi_mapal(cmd, prot_bytes,
1233                                                       &prot_iter, exp_data_len,
1234                                                       &data_iter))) {
1235                                 vq_err(vq, "Failed to map iov to sgl\n");
1236                                 vhost_scsi_release_cmd_res(&cmd->tvc_se_cmd);
1237                                 goto err;
1238                         }
1239                 }
1240                 /*
1241                  * Save the descriptor from vhost_get_vq_desc() to be used to
1242                  * complete the virtio-scsi request in TCM callback context via
1243                  * vhost_scsi_queue_data_in() and vhost_scsi_queue_status()
1244                  */
1245                 cmd->tvc_vq_desc = vc.head;
1246                 vhost_scsi_target_queue_cmd(cmd);
1247                 ret = 0;
1248 err:
1249                 /*
1250                  * ENXIO:  No more requests, or read error, wait for next kick
1251                  * EINVAL: Invalid response buffer, drop the request
1252                  * EIO:    Respond with bad target
1253                  * EAGAIN: Pending request
1254                  */
1255                 if (ret == -ENXIO)
1256                         break;
1257                 else if (ret == -EIO)
1258                         vhost_scsi_send_bad_target(vs, vq, vc.head, vc.out);
1259         } while (likely(!vhost_exceeds_weight(vq, ++c, 0)));
1260 out:
1261         mutex_unlock(&vq->mutex);
1262 }
1263
1264 static void
1265 vhost_scsi_send_tmf_resp(struct vhost_scsi *vs, struct vhost_virtqueue *vq,
1266                          int in_iovs, int vq_desc, struct iovec *resp_iov,
1267                          int tmf_resp_code)
1268 {
1269         struct virtio_scsi_ctrl_tmf_resp rsp;
1270         struct iov_iter iov_iter;
1271         int ret;
1272
1273         pr_debug("%s\n", __func__);
1274         memset(&rsp, 0, sizeof(rsp));
1275         rsp.response = tmf_resp_code;
1276
1277         iov_iter_init(&iov_iter, ITER_DEST, resp_iov, in_iovs, sizeof(rsp));
1278
1279         ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter);
1280         if (likely(ret == sizeof(rsp)))
1281                 vhost_add_used_and_signal(&vs->dev, vq, vq_desc, 0);
1282         else
1283                 pr_err("Faulted on virtio_scsi_ctrl_tmf_resp\n");
1284 }
1285
1286 static void vhost_scsi_tmf_resp_work(struct vhost_work *work)
1287 {
1288         struct vhost_scsi_tmf *tmf = container_of(work, struct vhost_scsi_tmf,
1289                                                   vwork);
1290         int resp_code;
1291
1292         if (tmf->scsi_resp == TMR_FUNCTION_COMPLETE)
1293                 resp_code = VIRTIO_SCSI_S_FUNCTION_SUCCEEDED;
1294         else
1295                 resp_code = VIRTIO_SCSI_S_FUNCTION_REJECTED;
1296
1297         vhost_scsi_send_tmf_resp(tmf->vhost, &tmf->svq->vq, tmf->in_iovs,
1298                                  tmf->vq_desc, &tmf->resp_iov, resp_code);
1299         vhost_scsi_release_tmf_res(tmf);
1300 }
1301
1302 static void vhost_scsi_tmf_flush_work(struct work_struct *work)
1303 {
1304         struct vhost_scsi_tmf *tmf = container_of(work, struct vhost_scsi_tmf,
1305                                                  flush_work);
1306         struct vhost_virtqueue *vq = &tmf->svq->vq;
1307         /*
1308          * Make sure we have sent responses for other commands before we
1309          * send our response.
1310          */
1311         vhost_dev_flush(vq->dev);
1312         if (!vhost_vq_work_queue(vq, &tmf->vwork))
1313                 vhost_scsi_release_tmf_res(tmf);
1314 }
1315
1316 static void
1317 vhost_scsi_handle_tmf(struct vhost_scsi *vs, struct vhost_scsi_tpg *tpg,
1318                       struct vhost_virtqueue *vq,
1319                       struct virtio_scsi_ctrl_tmf_req *vtmf,
1320                       struct vhost_scsi_ctx *vc)
1321 {
1322         struct vhost_scsi_virtqueue *svq = container_of(vq,
1323                                         struct vhost_scsi_virtqueue, vq);
1324         struct vhost_scsi_tmf *tmf;
1325
1326         if (vhost32_to_cpu(vq, vtmf->subtype) !=
1327             VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET)
1328                 goto send_reject;
1329
1330         if (!tpg->tpg_nexus || !tpg->tpg_nexus->tvn_se_sess) {
1331                 pr_err("Unable to locate active struct vhost_scsi_nexus for LUN RESET.\n");
1332                 goto send_reject;
1333         }
1334
1335         tmf = kzalloc(sizeof(*tmf), GFP_KERNEL);
1336         if (!tmf)
1337                 goto send_reject;
1338
1339         INIT_WORK(&tmf->flush_work, vhost_scsi_tmf_flush_work);
1340         vhost_work_init(&tmf->vwork, vhost_scsi_tmf_resp_work);
1341         tmf->vhost = vs;
1342         tmf->svq = svq;
1343         tmf->resp_iov = vq->iov[vc->out];
1344         tmf->vq_desc = vc->head;
1345         tmf->in_iovs = vc->in;
1346         tmf->inflight = vhost_scsi_get_inflight(vq);
1347
1348         if (target_submit_tmr(&tmf->se_cmd, tpg->tpg_nexus->tvn_se_sess, NULL,
1349                               vhost_buf_to_lun(vtmf->lun), NULL,
1350                               TMR_LUN_RESET, GFP_KERNEL, 0,
1351                               TARGET_SCF_ACK_KREF) < 0) {
1352                 vhost_scsi_release_tmf_res(tmf);
1353                 goto send_reject;
1354         }
1355
1356         return;
1357
1358 send_reject:
1359         vhost_scsi_send_tmf_resp(vs, vq, vc->in, vc->head, &vq->iov[vc->out],
1360                                  VIRTIO_SCSI_S_FUNCTION_REJECTED);
1361 }
1362
1363 static void
1364 vhost_scsi_send_an_resp(struct vhost_scsi *vs,
1365                         struct vhost_virtqueue *vq,
1366                         struct vhost_scsi_ctx *vc)
1367 {
1368         struct virtio_scsi_ctrl_an_resp rsp;
1369         struct iov_iter iov_iter;
1370         int ret;
1371
1372         pr_debug("%s\n", __func__);
1373         memset(&rsp, 0, sizeof(rsp));   /* event_actual = 0 */
1374         rsp.response = VIRTIO_SCSI_S_OK;
1375
1376         iov_iter_init(&iov_iter, ITER_DEST, &vq->iov[vc->out], vc->in, sizeof(rsp));
1377
1378         ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter);
1379         if (likely(ret == sizeof(rsp)))
1380                 vhost_add_used_and_signal(&vs->dev, vq, vc->head, 0);
1381         else
1382                 pr_err("Faulted on virtio_scsi_ctrl_an_resp\n");
1383 }
1384
1385 static void
1386 vhost_scsi_ctl_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
1387 {
1388         struct vhost_scsi_tpg *tpg;
1389         union {
1390                 __virtio32 type;
1391                 struct virtio_scsi_ctrl_an_req an;
1392                 struct virtio_scsi_ctrl_tmf_req tmf;
1393         } v_req;
1394         struct vhost_scsi_ctx vc;
1395         size_t typ_size;
1396         int ret, c = 0;
1397
1398         mutex_lock(&vq->mutex);
1399         /*
1400          * We can handle the vq only after the endpoint is setup by calling the
1401          * VHOST_SCSI_SET_ENDPOINT ioctl.
1402          */
1403         if (!vhost_vq_get_backend(vq))
1404                 goto out;
1405
1406         memset(&vc, 0, sizeof(vc));
1407
1408         vhost_disable_notify(&vs->dev, vq);
1409
1410         do {
1411                 ret = vhost_scsi_get_desc(vs, vq, &vc);
1412                 if (ret)
1413                         goto err;
1414
1415                 /*
1416                  * Get the request type first in order to setup
1417                  * other parameters dependent on the type.
1418                  */
1419                 vc.req = &v_req.type;
1420                 typ_size = sizeof(v_req.type);
1421
1422                 if (unlikely(!copy_from_iter_full(vc.req, typ_size,
1423                                                   &vc.out_iter))) {
1424                         vq_err(vq, "Faulted on copy_from_iter tmf type\n");
1425                         /*
1426                          * The size of the response buffer depends on the
1427                          * request type and must be validated against it.
1428                          * Since the request type is not known, don't send
1429                          * a response.
1430                          */
1431                         continue;
1432                 }
1433
1434                 switch (vhost32_to_cpu(vq, v_req.type)) {
1435                 case VIRTIO_SCSI_T_TMF:
1436                         vc.req = &v_req.tmf;
1437                         vc.req_size = sizeof(struct virtio_scsi_ctrl_tmf_req);
1438                         vc.rsp_size = sizeof(struct virtio_scsi_ctrl_tmf_resp);
1439                         vc.lunp = &v_req.tmf.lun[0];
1440                         vc.target = &v_req.tmf.lun[1];
1441                         break;
1442                 case VIRTIO_SCSI_T_AN_QUERY:
1443                 case VIRTIO_SCSI_T_AN_SUBSCRIBE:
1444                         vc.req = &v_req.an;
1445                         vc.req_size = sizeof(struct virtio_scsi_ctrl_an_req);
1446                         vc.rsp_size = sizeof(struct virtio_scsi_ctrl_an_resp);
1447                         vc.lunp = &v_req.an.lun[0];
1448                         vc.target = NULL;
1449                         break;
1450                 default:
1451                         vq_err(vq, "Unknown control request %d", v_req.type);
1452                         continue;
1453                 }
1454
1455                 /*
1456                  * Validate the size of request and response buffers.
1457                  * Check for a sane response buffer so we can report
1458                  * early errors back to the guest.
1459                  */
1460                 ret = vhost_scsi_chk_size(vq, &vc);
1461                 if (ret)
1462                         goto err;
1463
1464                 /*
1465                  * Get the rest of the request now that its size is known.
1466                  */
1467                 vc.req += typ_size;
1468                 vc.req_size -= typ_size;
1469
1470                 ret = vhost_scsi_get_req(vq, &vc, &tpg);
1471                 if (ret)
1472                         goto err;
1473
1474                 if (v_req.type == VIRTIO_SCSI_T_TMF)
1475                         vhost_scsi_handle_tmf(vs, tpg, vq, &v_req.tmf, &vc);
1476                 else
1477                         vhost_scsi_send_an_resp(vs, vq, &vc);
1478 err:
1479                 /*
1480                  * ENXIO:  No more requests, or read error, wait for next kick
1481                  * EINVAL: Invalid response buffer, drop the request
1482                  * EIO:    Respond with bad target
1483                  * EAGAIN: Pending request
1484                  */
1485                 if (ret == -ENXIO)
1486                         break;
1487                 else if (ret == -EIO)
1488                         vhost_scsi_send_bad_target(vs, vq, vc.head, vc.out);
1489         } while (likely(!vhost_exceeds_weight(vq, ++c, 0)));
1490 out:
1491         mutex_unlock(&vq->mutex);
1492 }
1493
1494 static void vhost_scsi_ctl_handle_kick(struct vhost_work *work)
1495 {
1496         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1497                                                 poll.work);
1498         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1499
1500         pr_debug("%s: The handling func for control queue.\n", __func__);
1501         vhost_scsi_ctl_handle_vq(vs, vq);
1502 }
1503
1504 static void
1505 vhost_scsi_send_evt(struct vhost_scsi *vs, struct vhost_virtqueue *vq,
1506                     struct vhost_scsi_tpg *tpg, struct se_lun *lun,
1507                     u32 event, u32 reason)
1508 {
1509         struct vhost_scsi_evt *evt;
1510
1511         evt = vhost_scsi_allocate_evt(vs, event, reason);
1512         if (!evt)
1513                 return;
1514
1515         if (tpg && lun) {
1516                 /* TODO: share lun setup code with virtio-scsi.ko */
1517                 /*
1518                  * Note: evt->event is zeroed when we allocate it and
1519                  * lun[4-7] need to be zero according to virtio-scsi spec.
1520                  */
1521                 evt->event.lun[0] = 0x01;
1522                 evt->event.lun[1] = tpg->tport_tpgt;
1523                 if (lun->unpacked_lun >= 256)
1524                         evt->event.lun[2] = lun->unpacked_lun >> 8 | 0x40 ;
1525                 evt->event.lun[3] = lun->unpacked_lun & 0xFF;
1526         }
1527
1528         llist_add(&evt->list, &vs->vs_event_list);
1529         if (!vhost_vq_work_queue(vq, &vs->vs_event_work))
1530                 vhost_scsi_complete_events(vs, true);
1531 }
1532
1533 static void vhost_scsi_evt_handle_kick(struct vhost_work *work)
1534 {
1535         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1536                                                 poll.work);
1537         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1538
1539         mutex_lock(&vq->mutex);
1540         if (!vhost_vq_get_backend(vq))
1541                 goto out;
1542
1543         if (vs->vs_events_missed)
1544                 vhost_scsi_send_evt(vs, vq, NULL, NULL, VIRTIO_SCSI_T_NO_EVENT,
1545                                     0);
1546 out:
1547         mutex_unlock(&vq->mutex);
1548 }
1549
1550 static void vhost_scsi_handle_kick(struct vhost_work *work)
1551 {
1552         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1553                                                 poll.work);
1554         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1555
1556         vhost_scsi_handle_vq(vs, vq);
1557 }
1558
1559 /* Callers must hold dev mutex */
1560 static void vhost_scsi_flush(struct vhost_scsi *vs)
1561 {
1562         int i;
1563
1564         /* Init new inflight and remember the old inflight */
1565         vhost_scsi_init_inflight(vs, vs->old_inflight);
1566
1567         /*
1568          * The inflight->kref was initialized to 1. We decrement it here to
1569          * indicate the start of the flush operation so that it will reach 0
1570          * when all the reqs are finished.
1571          */
1572         for (i = 0; i < vs->dev.nvqs; i++)
1573                 kref_put(&vs->old_inflight[i]->kref, vhost_scsi_done_inflight);
1574
1575         /* Flush both the vhost poll and vhost work */
1576         vhost_dev_flush(&vs->dev);
1577
1578         /* Wait for all reqs issued before the flush to be finished */
1579         for (i = 0; i < vs->dev.nvqs; i++)
1580                 wait_for_completion(&vs->old_inflight[i]->comp);
1581 }
1582
1583 static void vhost_scsi_destroy_vq_cmds(struct vhost_virtqueue *vq)
1584 {
1585         struct vhost_scsi_virtqueue *svq = container_of(vq,
1586                                         struct vhost_scsi_virtqueue, vq);
1587         struct vhost_scsi_cmd *tv_cmd;
1588         unsigned int i;
1589
1590         if (!svq->scsi_cmds)
1591                 return;
1592
1593         for (i = 0; i < svq->max_cmds; i++) {
1594                 tv_cmd = &svq->scsi_cmds[i];
1595
1596                 kfree(tv_cmd->tvc_sgl);
1597                 kfree(tv_cmd->tvc_prot_sgl);
1598                 kfree(tv_cmd->tvc_upages);
1599                 kfree(tv_cmd->tvc_resp_iov);
1600         }
1601
1602         sbitmap_free(&svq->scsi_tags);
1603         kfree(svq->scsi_cmds);
1604         svq->scsi_cmds = NULL;
1605 }
1606
1607 static int vhost_scsi_setup_vq_cmds(struct vhost_virtqueue *vq, int max_cmds)
1608 {
1609         struct vhost_scsi_virtqueue *svq = container_of(vq,
1610                                         struct vhost_scsi_virtqueue, vq);
1611         struct vhost_scsi_cmd *tv_cmd;
1612         unsigned int i;
1613
1614         if (svq->scsi_cmds)
1615                 return 0;
1616
1617         if (sbitmap_init_node(&svq->scsi_tags, max_cmds, -1, GFP_KERNEL,
1618                               NUMA_NO_NODE, false, true))
1619                 return -ENOMEM;
1620         svq->max_cmds = max_cmds;
1621
1622         svq->scsi_cmds = kcalloc(max_cmds, sizeof(*tv_cmd), GFP_KERNEL);
1623         if (!svq->scsi_cmds) {
1624                 sbitmap_free(&svq->scsi_tags);
1625                 return -ENOMEM;
1626         }
1627
1628         for (i = 0; i < max_cmds; i++) {
1629                 tv_cmd = &svq->scsi_cmds[i];
1630
1631                 tv_cmd->tvc_sgl = kcalloc(VHOST_SCSI_PREALLOC_SGLS,
1632                                           sizeof(struct scatterlist),
1633                                           GFP_KERNEL);
1634                 if (!tv_cmd->tvc_sgl) {
1635                         pr_err("Unable to allocate tv_cmd->tvc_sgl\n");
1636                         goto out;
1637                 }
1638
1639                 tv_cmd->tvc_upages = kcalloc(VHOST_SCSI_PREALLOC_UPAGES,
1640                                              sizeof(struct page *),
1641                                              GFP_KERNEL);
1642                 if (!tv_cmd->tvc_upages) {
1643                         pr_err("Unable to allocate tv_cmd->tvc_upages\n");
1644                         goto out;
1645                 }
1646
1647                 tv_cmd->tvc_resp_iov = kcalloc(UIO_MAXIOV,
1648                                                sizeof(struct iovec),
1649                                                GFP_KERNEL);
1650                 if (!tv_cmd->tvc_resp_iov) {
1651                         pr_err("Unable to allocate tv_cmd->tvc_resp_iov\n");
1652                         goto out;
1653                 }
1654
1655                 tv_cmd->tvc_prot_sgl = kcalloc(VHOST_SCSI_PREALLOC_PROT_SGLS,
1656                                                sizeof(struct scatterlist),
1657                                                GFP_KERNEL);
1658                 if (!tv_cmd->tvc_prot_sgl) {
1659                         pr_err("Unable to allocate tv_cmd->tvc_prot_sgl\n");
1660                         goto out;
1661                 }
1662         }
1663         return 0;
1664 out:
1665         vhost_scsi_destroy_vq_cmds(vq);
1666         return -ENOMEM;
1667 }
1668
1669 /*
1670  * Called from vhost_scsi_ioctl() context to walk the list of available
1671  * vhost_scsi_tpg with an active struct vhost_scsi_nexus
1672  *
1673  *  The lock nesting rule is:
1674  *    vs->dev.mutex -> vhost_scsi_mutex -> tpg->tv_tpg_mutex -> vq->mutex
1675  */
1676 static int
1677 vhost_scsi_set_endpoint(struct vhost_scsi *vs,
1678                         struct vhost_scsi_target *t)
1679 {
1680         struct se_portal_group *se_tpg;
1681         struct vhost_scsi_tport *tv_tport;
1682         struct vhost_scsi_tpg *tpg;
1683         struct vhost_scsi_tpg **vs_tpg;
1684         struct vhost_virtqueue *vq;
1685         int index, ret, i, len;
1686         bool match = false;
1687
1688         mutex_lock(&vs->dev.mutex);
1689
1690         /* Verify that ring has been setup correctly. */
1691         for (index = 0; index < vs->dev.nvqs; ++index) {
1692                 /* Verify that ring has been setup correctly. */
1693                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1694                         ret = -EFAULT;
1695                         goto out;
1696                 }
1697         }
1698
1699         len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET;
1700         vs_tpg = kzalloc(len, GFP_KERNEL);
1701         if (!vs_tpg) {
1702                 ret = -ENOMEM;
1703                 goto out;
1704         }
1705         if (vs->vs_tpg)
1706                 memcpy(vs_tpg, vs->vs_tpg, len);
1707
1708         mutex_lock(&vhost_scsi_mutex);
1709         list_for_each_entry(tpg, &vhost_scsi_list, tv_tpg_list) {
1710                 mutex_lock(&tpg->tv_tpg_mutex);
1711                 if (!tpg->tpg_nexus) {
1712                         mutex_unlock(&tpg->tv_tpg_mutex);
1713                         continue;
1714                 }
1715                 if (tpg->tv_tpg_vhost_count != 0) {
1716                         mutex_unlock(&tpg->tv_tpg_mutex);
1717                         continue;
1718                 }
1719                 tv_tport = tpg->tport;
1720
1721                 if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1722                         if (vs->vs_tpg && vs->vs_tpg[tpg->tport_tpgt]) {
1723                                 mutex_unlock(&tpg->tv_tpg_mutex);
1724                                 mutex_unlock(&vhost_scsi_mutex);
1725                                 ret = -EEXIST;
1726                                 goto undepend;
1727                         }
1728                         /*
1729                          * In order to ensure individual vhost-scsi configfs
1730                          * groups cannot be removed while in use by vhost ioctl,
1731                          * go ahead and take an explicit se_tpg->tpg_group.cg_item
1732                          * dependency now.
1733                          */
1734                         se_tpg = &tpg->se_tpg;
1735                         ret = target_depend_item(&se_tpg->tpg_group.cg_item);
1736                         if (ret) {
1737                                 pr_warn("target_depend_item() failed: %d\n", ret);
1738                                 mutex_unlock(&tpg->tv_tpg_mutex);
1739                                 mutex_unlock(&vhost_scsi_mutex);
1740                                 goto undepend;
1741                         }
1742                         tpg->tv_tpg_vhost_count++;
1743                         tpg->vhost_scsi = vs;
1744                         vs_tpg[tpg->tport_tpgt] = tpg;
1745                         match = true;
1746                 }
1747                 mutex_unlock(&tpg->tv_tpg_mutex);
1748         }
1749         mutex_unlock(&vhost_scsi_mutex);
1750
1751         if (match) {
1752                 memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
1753                        sizeof(vs->vs_vhost_wwpn));
1754
1755                 for (i = VHOST_SCSI_VQ_IO; i < vs->dev.nvqs; i++) {
1756                         vq = &vs->vqs[i].vq;
1757                         if (!vhost_vq_is_setup(vq))
1758                                 continue;
1759
1760                         ret = vhost_scsi_setup_vq_cmds(vq, vq->num);
1761                         if (ret)
1762                                 goto destroy_vq_cmds;
1763                 }
1764
1765                 for (i = 0; i < vs->dev.nvqs; i++) {
1766                         vq = &vs->vqs[i].vq;
1767                         mutex_lock(&vq->mutex);
1768                         vhost_vq_set_backend(vq, vs_tpg);
1769                         vhost_vq_init_access(vq);
1770                         mutex_unlock(&vq->mutex);
1771                 }
1772                 ret = 0;
1773         } else {
1774                 ret = -EEXIST;
1775         }
1776
1777         /*
1778          * Act as synchronize_rcu to make sure access to
1779          * old vs->vs_tpg is finished.
1780          */
1781         vhost_scsi_flush(vs);
1782         kfree(vs->vs_tpg);
1783         vs->vs_tpg = vs_tpg;
1784         goto out;
1785
1786 destroy_vq_cmds:
1787         for (i--; i >= VHOST_SCSI_VQ_IO; i--) {
1788                 if (!vhost_vq_get_backend(&vs->vqs[i].vq))
1789                         vhost_scsi_destroy_vq_cmds(&vs->vqs[i].vq);
1790         }
1791 undepend:
1792         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1793                 tpg = vs_tpg[i];
1794                 if (tpg) {
1795                         mutex_lock(&tpg->tv_tpg_mutex);
1796                         tpg->vhost_scsi = NULL;
1797                         tpg->tv_tpg_vhost_count--;
1798                         mutex_unlock(&tpg->tv_tpg_mutex);
1799                         target_undepend_item(&tpg->se_tpg.tpg_group.cg_item);
1800                 }
1801         }
1802         kfree(vs_tpg);
1803 out:
1804         mutex_unlock(&vs->dev.mutex);
1805         return ret;
1806 }
1807
1808 static int
1809 vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
1810                           struct vhost_scsi_target *t)
1811 {
1812         struct se_portal_group *se_tpg;
1813         struct vhost_scsi_tport *tv_tport;
1814         struct vhost_scsi_tpg *tpg;
1815         struct vhost_virtqueue *vq;
1816         bool match = false;
1817         int index, ret, i;
1818         u8 target;
1819
1820         mutex_lock(&vs->dev.mutex);
1821         /* Verify that ring has been setup correctly. */
1822         for (index = 0; index < vs->dev.nvqs; ++index) {
1823                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1824                         ret = -EFAULT;
1825                         goto err_dev;
1826                 }
1827         }
1828
1829         if (!vs->vs_tpg) {
1830                 ret = 0;
1831                 goto err_dev;
1832         }
1833
1834         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1835                 target = i;
1836                 tpg = vs->vs_tpg[target];
1837                 if (!tpg)
1838                         continue;
1839
1840                 tv_tport = tpg->tport;
1841                 if (!tv_tport) {
1842                         ret = -ENODEV;
1843                         goto err_dev;
1844                 }
1845
1846                 if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1847                         pr_warn("tv_tport->tport_name: %s, tpg->tport_tpgt: %hu"
1848                                 " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
1849                                 tv_tport->tport_name, tpg->tport_tpgt,
1850                                 t->vhost_wwpn, t->vhost_tpgt);
1851                         ret = -EINVAL;
1852                         goto err_dev;
1853                 }
1854                 match = true;
1855         }
1856         if (!match)
1857                 goto free_vs_tpg;
1858
1859         /* Prevent new cmds from starting and accessing the tpgs/sessions */
1860         for (i = 0; i < vs->dev.nvqs; i++) {
1861                 vq = &vs->vqs[i].vq;
1862                 mutex_lock(&vq->mutex);
1863                 vhost_vq_set_backend(vq, NULL);
1864                 mutex_unlock(&vq->mutex);
1865         }
1866         /* Make sure cmds are not running before tearing them down. */
1867         vhost_scsi_flush(vs);
1868
1869         for (i = 0; i < vs->dev.nvqs; i++) {
1870                 vq = &vs->vqs[i].vq;
1871                 vhost_scsi_destroy_vq_cmds(vq);
1872         }
1873
1874         /*
1875          * We can now release our hold on the tpg and sessions and userspace
1876          * can free them after this point.
1877          */
1878         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1879                 target = i;
1880                 tpg = vs->vs_tpg[target];
1881                 if (!tpg)
1882                         continue;
1883
1884                 mutex_lock(&tpg->tv_tpg_mutex);
1885
1886                 tpg->tv_tpg_vhost_count--;
1887                 tpg->vhost_scsi = NULL;
1888                 vs->vs_tpg[target] = NULL;
1889
1890                 mutex_unlock(&tpg->tv_tpg_mutex);
1891
1892                 se_tpg = &tpg->se_tpg;
1893                 target_undepend_item(&se_tpg->tpg_group.cg_item);
1894         }
1895
1896 free_vs_tpg:
1897         /*
1898          * Act as synchronize_rcu to make sure access to
1899          * old vs->vs_tpg is finished.
1900          */
1901         vhost_scsi_flush(vs);
1902         kfree(vs->vs_tpg);
1903         vs->vs_tpg = NULL;
1904         WARN_ON(vs->vs_events_nr);
1905         mutex_unlock(&vs->dev.mutex);
1906         return 0;
1907
1908 err_dev:
1909         mutex_unlock(&vs->dev.mutex);
1910         return ret;
1911 }
1912
1913 static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features)
1914 {
1915         struct vhost_virtqueue *vq;
1916         int i;
1917
1918         if (features & ~VHOST_SCSI_FEATURES)
1919                 return -EOPNOTSUPP;
1920
1921         mutex_lock(&vs->dev.mutex);
1922         if ((features & (1 << VHOST_F_LOG_ALL)) &&
1923             !vhost_log_access_ok(&vs->dev)) {
1924                 mutex_unlock(&vs->dev.mutex);
1925                 return -EFAULT;
1926         }
1927
1928         for (i = 0; i < vs->dev.nvqs; i++) {
1929                 vq = &vs->vqs[i].vq;
1930                 mutex_lock(&vq->mutex);
1931                 vq->acked_features = features;
1932                 mutex_unlock(&vq->mutex);
1933         }
1934         mutex_unlock(&vs->dev.mutex);
1935         return 0;
1936 }
1937
1938 static int vhost_scsi_open(struct inode *inode, struct file *f)
1939 {
1940         struct vhost_scsi_virtqueue *svq;
1941         struct vhost_scsi *vs;
1942         struct vhost_virtqueue **vqs;
1943         int r = -ENOMEM, i, nvqs = vhost_scsi_max_io_vqs;
1944
1945         vs = kvzalloc(sizeof(*vs), GFP_KERNEL);
1946         if (!vs)
1947                 goto err_vs;
1948
1949         if (nvqs > VHOST_SCSI_MAX_IO_VQ) {
1950                 pr_err("Invalid max_io_vqs of %d. Using %d.\n", nvqs,
1951                        VHOST_SCSI_MAX_IO_VQ);
1952                 nvqs = VHOST_SCSI_MAX_IO_VQ;
1953         } else if (nvqs == 0) {
1954                 pr_err("Invalid max_io_vqs of %d. Using 1.\n", nvqs);
1955                 nvqs = 1;
1956         }
1957         nvqs += VHOST_SCSI_VQ_IO;
1958
1959         vs->old_inflight = kmalloc_array(nvqs, sizeof(*vs->old_inflight),
1960                                          GFP_KERNEL | __GFP_ZERO);
1961         if (!vs->old_inflight)
1962                 goto err_inflight;
1963
1964         vs->vqs = kmalloc_array(nvqs, sizeof(*vs->vqs),
1965                                 GFP_KERNEL | __GFP_ZERO);
1966         if (!vs->vqs)
1967                 goto err_vqs;
1968
1969         vqs = kmalloc_array(nvqs, sizeof(*vqs), GFP_KERNEL);
1970         if (!vqs)
1971                 goto err_local_vqs;
1972
1973         vhost_work_init(&vs->vs_event_work, vhost_scsi_evt_work);
1974
1975         vs->vs_events_nr = 0;
1976         vs->vs_events_missed = false;
1977
1978         vqs[VHOST_SCSI_VQ_CTL] = &vs->vqs[VHOST_SCSI_VQ_CTL].vq;
1979         vqs[VHOST_SCSI_VQ_EVT] = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1980         vs->vqs[VHOST_SCSI_VQ_CTL].vq.handle_kick = vhost_scsi_ctl_handle_kick;
1981         vs->vqs[VHOST_SCSI_VQ_EVT].vq.handle_kick = vhost_scsi_evt_handle_kick;
1982         for (i = VHOST_SCSI_VQ_IO; i < nvqs; i++) {
1983                 svq = &vs->vqs[i];
1984
1985                 vqs[i] = &svq->vq;
1986                 svq->vs = vs;
1987                 init_llist_head(&svq->completion_list);
1988                 vhost_work_init(&svq->completion_work,
1989                                 vhost_scsi_complete_cmd_work);
1990                 svq->vq.handle_kick = vhost_scsi_handle_kick;
1991         }
1992         vhost_dev_init(&vs->dev, vqs, nvqs, UIO_MAXIOV,
1993                        VHOST_SCSI_WEIGHT, 0, true, NULL);
1994
1995         vhost_scsi_init_inflight(vs, NULL);
1996
1997         f->private_data = vs;
1998         return 0;
1999
2000 err_local_vqs:
2001         kfree(vs->vqs);
2002 err_vqs:
2003         kfree(vs->old_inflight);
2004 err_inflight:
2005         kvfree(vs);
2006 err_vs:
2007         return r;
2008 }
2009
2010 static int vhost_scsi_release(struct inode *inode, struct file *f)
2011 {
2012         struct vhost_scsi *vs = f->private_data;
2013         struct vhost_scsi_target t;
2014
2015         mutex_lock(&vs->dev.mutex);
2016         memcpy(t.vhost_wwpn, vs->vs_vhost_wwpn, sizeof(t.vhost_wwpn));
2017         mutex_unlock(&vs->dev.mutex);
2018         vhost_scsi_clear_endpoint(vs, &t);
2019         vhost_dev_stop(&vs->dev);
2020         vhost_dev_cleanup(&vs->dev);
2021         kfree(vs->dev.vqs);
2022         kfree(vs->vqs);
2023         kfree(vs->old_inflight);
2024         kvfree(vs);
2025         return 0;
2026 }
2027
2028 static long
2029 vhost_scsi_ioctl(struct file *f,
2030                  unsigned int ioctl,
2031                  unsigned long arg)
2032 {
2033         struct vhost_scsi *vs = f->private_data;
2034         struct vhost_scsi_target backend;
2035         void __user *argp = (void __user *)arg;
2036         u64 __user *featurep = argp;
2037         u32 __user *eventsp = argp;
2038         u32 events_missed;
2039         u64 features;
2040         int r, abi_version = VHOST_SCSI_ABI_VERSION;
2041         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
2042
2043         switch (ioctl) {
2044         case VHOST_SCSI_SET_ENDPOINT:
2045                 if (copy_from_user(&backend, argp, sizeof backend))
2046                         return -EFAULT;
2047                 if (backend.reserved != 0)
2048                         return -EOPNOTSUPP;
2049
2050                 return vhost_scsi_set_endpoint(vs, &backend);
2051         case VHOST_SCSI_CLEAR_ENDPOINT:
2052                 if (copy_from_user(&backend, argp, sizeof backend))
2053                         return -EFAULT;
2054                 if (backend.reserved != 0)
2055                         return -EOPNOTSUPP;
2056
2057                 return vhost_scsi_clear_endpoint(vs, &backend);
2058         case VHOST_SCSI_GET_ABI_VERSION:
2059                 if (copy_to_user(argp, &abi_version, sizeof abi_version))
2060                         return -EFAULT;
2061                 return 0;
2062         case VHOST_SCSI_SET_EVENTS_MISSED:
2063                 if (get_user(events_missed, eventsp))
2064                         return -EFAULT;
2065                 mutex_lock(&vq->mutex);
2066                 vs->vs_events_missed = events_missed;
2067                 mutex_unlock(&vq->mutex);
2068                 return 0;
2069         case VHOST_SCSI_GET_EVENTS_MISSED:
2070                 mutex_lock(&vq->mutex);
2071                 events_missed = vs->vs_events_missed;
2072                 mutex_unlock(&vq->mutex);
2073                 if (put_user(events_missed, eventsp))
2074                         return -EFAULT;
2075                 return 0;
2076         case VHOST_GET_FEATURES:
2077                 features = VHOST_SCSI_FEATURES;
2078                 if (copy_to_user(featurep, &features, sizeof features))
2079                         return -EFAULT;
2080                 return 0;
2081         case VHOST_SET_FEATURES:
2082                 if (copy_from_user(&features, featurep, sizeof features))
2083                         return -EFAULT;
2084                 return vhost_scsi_set_features(vs, features);
2085         case VHOST_NEW_WORKER:
2086         case VHOST_FREE_WORKER:
2087         case VHOST_ATTACH_VRING_WORKER:
2088         case VHOST_GET_VRING_WORKER:
2089                 mutex_lock(&vs->dev.mutex);
2090                 r = vhost_worker_ioctl(&vs->dev, ioctl, argp);
2091                 mutex_unlock(&vs->dev.mutex);
2092                 return r;
2093         default:
2094                 mutex_lock(&vs->dev.mutex);
2095                 r = vhost_dev_ioctl(&vs->dev, ioctl, argp);
2096                 /* TODO: flush backend after dev ioctl. */
2097                 if (r == -ENOIOCTLCMD)
2098                         r = vhost_vring_ioctl(&vs->dev, ioctl, argp);
2099                 mutex_unlock(&vs->dev.mutex);
2100                 return r;
2101         }
2102 }
2103
2104 static const struct file_operations vhost_scsi_fops = {
2105         .owner          = THIS_MODULE,
2106         .release        = vhost_scsi_release,
2107         .unlocked_ioctl = vhost_scsi_ioctl,
2108         .compat_ioctl   = compat_ptr_ioctl,
2109         .open           = vhost_scsi_open,
2110         .llseek         = noop_llseek,
2111 };
2112
2113 static struct miscdevice vhost_scsi_misc = {
2114         MISC_DYNAMIC_MINOR,
2115         "vhost-scsi",
2116         &vhost_scsi_fops,
2117 };
2118
2119 static int __init vhost_scsi_register(void)
2120 {
2121         return misc_register(&vhost_scsi_misc);
2122 }
2123
2124 static void vhost_scsi_deregister(void)
2125 {
2126         misc_deregister(&vhost_scsi_misc);
2127 }
2128
2129 static char *vhost_scsi_dump_proto_id(struct vhost_scsi_tport *tport)
2130 {
2131         switch (tport->tport_proto_id) {
2132         case SCSI_PROTOCOL_SAS:
2133                 return "SAS";
2134         case SCSI_PROTOCOL_FCP:
2135                 return "FCP";
2136         case SCSI_PROTOCOL_ISCSI:
2137                 return "iSCSI";
2138         default:
2139                 break;
2140         }
2141
2142         return "Unknown";
2143 }
2144
2145 static void
2146 vhost_scsi_do_plug(struct vhost_scsi_tpg *tpg,
2147                   struct se_lun *lun, bool plug)
2148 {
2149
2150         struct vhost_scsi *vs = tpg->vhost_scsi;
2151         struct vhost_virtqueue *vq;
2152         u32 reason;
2153
2154         if (!vs)
2155                 return;
2156
2157         if (plug)
2158                 reason = VIRTIO_SCSI_EVT_RESET_RESCAN;
2159         else
2160                 reason = VIRTIO_SCSI_EVT_RESET_REMOVED;
2161
2162         vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
2163         mutex_lock(&vq->mutex);
2164         /*
2165          * We can't queue events if the backend has been cleared, because
2166          * we could end up queueing an event after the flush.
2167          */
2168         if (!vhost_vq_get_backend(vq))
2169                 goto unlock;
2170
2171         if (vhost_has_feature(vq, VIRTIO_SCSI_F_HOTPLUG))
2172                 vhost_scsi_send_evt(vs, vq, tpg, lun,
2173                                    VIRTIO_SCSI_T_TRANSPORT_RESET, reason);
2174 unlock:
2175         mutex_unlock(&vq->mutex);
2176 }
2177
2178 static void vhost_scsi_hotplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
2179 {
2180         vhost_scsi_do_plug(tpg, lun, true);
2181 }
2182
2183 static void vhost_scsi_hotunplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
2184 {
2185         vhost_scsi_do_plug(tpg, lun, false);
2186 }
2187
2188 static int vhost_scsi_port_link(struct se_portal_group *se_tpg,
2189                                struct se_lun *lun)
2190 {
2191         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2192                                 struct vhost_scsi_tpg, se_tpg);
2193
2194         mutex_lock(&tpg->tv_tpg_mutex);
2195         tpg->tv_tpg_port_count++;
2196         vhost_scsi_hotplug(tpg, lun);
2197         mutex_unlock(&tpg->tv_tpg_mutex);
2198
2199         return 0;
2200 }
2201
2202 static void vhost_scsi_port_unlink(struct se_portal_group *se_tpg,
2203                                   struct se_lun *lun)
2204 {
2205         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2206                                 struct vhost_scsi_tpg, se_tpg);
2207
2208         mutex_lock(&tpg->tv_tpg_mutex);
2209         tpg->tv_tpg_port_count--;
2210         vhost_scsi_hotunplug(tpg, lun);
2211         mutex_unlock(&tpg->tv_tpg_mutex);
2212 }
2213
2214 static ssize_t vhost_scsi_tpg_attrib_fabric_prot_type_store(
2215                 struct config_item *item, const char *page, size_t count)
2216 {
2217         struct se_portal_group *se_tpg = attrib_to_tpg(item);
2218         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2219                                 struct vhost_scsi_tpg, se_tpg);
2220         unsigned long val;
2221         int ret = kstrtoul(page, 0, &val);
2222
2223         if (ret) {
2224                 pr_err("kstrtoul() returned %d for fabric_prot_type\n", ret);
2225                 return ret;
2226         }
2227         if (val != 0 && val != 1 && val != 3) {
2228                 pr_err("Invalid vhost_scsi fabric_prot_type: %lu\n", val);
2229                 return -EINVAL;
2230         }
2231         tpg->tv_fabric_prot_type = val;
2232
2233         return count;
2234 }
2235
2236 static ssize_t vhost_scsi_tpg_attrib_fabric_prot_type_show(
2237                 struct config_item *item, char *page)
2238 {
2239         struct se_portal_group *se_tpg = attrib_to_tpg(item);
2240         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2241                                 struct vhost_scsi_tpg, se_tpg);
2242
2243         return sysfs_emit(page, "%d\n", tpg->tv_fabric_prot_type);
2244 }
2245
2246 CONFIGFS_ATTR(vhost_scsi_tpg_attrib_, fabric_prot_type);
2247
2248 static struct configfs_attribute *vhost_scsi_tpg_attrib_attrs[] = {
2249         &vhost_scsi_tpg_attrib_attr_fabric_prot_type,
2250         NULL,
2251 };
2252
2253 static int vhost_scsi_make_nexus(struct vhost_scsi_tpg *tpg,
2254                                 const char *name)
2255 {
2256         struct vhost_scsi_nexus *tv_nexus;
2257
2258         mutex_lock(&tpg->tv_tpg_mutex);
2259         if (tpg->tpg_nexus) {
2260                 mutex_unlock(&tpg->tv_tpg_mutex);
2261                 pr_debug("tpg->tpg_nexus already exists\n");
2262                 return -EEXIST;
2263         }
2264
2265         tv_nexus = kzalloc(sizeof(*tv_nexus), GFP_KERNEL);
2266         if (!tv_nexus) {
2267                 mutex_unlock(&tpg->tv_tpg_mutex);
2268                 pr_err("Unable to allocate struct vhost_scsi_nexus\n");
2269                 return -ENOMEM;
2270         }
2271         /*
2272          * Since we are running in 'demo mode' this call with generate a
2273          * struct se_node_acl for the vhost_scsi struct se_portal_group with
2274          * the SCSI Initiator port name of the passed configfs group 'name'.
2275          */
2276         tv_nexus->tvn_se_sess = target_setup_session(&tpg->se_tpg, 0, 0,
2277                                         TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS,
2278                                         (unsigned char *)name, tv_nexus, NULL);
2279         if (IS_ERR(tv_nexus->tvn_se_sess)) {
2280                 mutex_unlock(&tpg->tv_tpg_mutex);
2281                 kfree(tv_nexus);
2282                 return -ENOMEM;
2283         }
2284         tpg->tpg_nexus = tv_nexus;
2285
2286         mutex_unlock(&tpg->tv_tpg_mutex);
2287         return 0;
2288 }
2289
2290 static int vhost_scsi_drop_nexus(struct vhost_scsi_tpg *tpg)
2291 {
2292         struct se_session *se_sess;
2293         struct vhost_scsi_nexus *tv_nexus;
2294
2295         mutex_lock(&tpg->tv_tpg_mutex);
2296         tv_nexus = tpg->tpg_nexus;
2297         if (!tv_nexus) {
2298                 mutex_unlock(&tpg->tv_tpg_mutex);
2299                 return -ENODEV;
2300         }
2301
2302         se_sess = tv_nexus->tvn_se_sess;
2303         if (!se_sess) {
2304                 mutex_unlock(&tpg->tv_tpg_mutex);
2305                 return -ENODEV;
2306         }
2307
2308         if (tpg->tv_tpg_port_count != 0) {
2309                 mutex_unlock(&tpg->tv_tpg_mutex);
2310                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
2311                         " active TPG port count: %d\n",
2312                         tpg->tv_tpg_port_count);
2313                 return -EBUSY;
2314         }
2315
2316         if (tpg->tv_tpg_vhost_count != 0) {
2317                 mutex_unlock(&tpg->tv_tpg_mutex);
2318                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
2319                         " active TPG vhost count: %d\n",
2320                         tpg->tv_tpg_vhost_count);
2321                 return -EBUSY;
2322         }
2323
2324         pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated"
2325                 " %s Initiator Port: %s\n", vhost_scsi_dump_proto_id(tpg->tport),
2326                 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
2327
2328         /*
2329          * Release the SCSI I_T Nexus to the emulated vhost Target Port
2330          */
2331         target_remove_session(se_sess);
2332         tpg->tpg_nexus = NULL;
2333         mutex_unlock(&tpg->tv_tpg_mutex);
2334
2335         kfree(tv_nexus);
2336         return 0;
2337 }
2338
2339 static ssize_t vhost_scsi_tpg_nexus_show(struct config_item *item, char *page)
2340 {
2341         struct se_portal_group *se_tpg = to_tpg(item);
2342         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2343                                 struct vhost_scsi_tpg, se_tpg);
2344         struct vhost_scsi_nexus *tv_nexus;
2345         ssize_t ret;
2346
2347         mutex_lock(&tpg->tv_tpg_mutex);
2348         tv_nexus = tpg->tpg_nexus;
2349         if (!tv_nexus) {
2350                 mutex_unlock(&tpg->tv_tpg_mutex);
2351                 return -ENODEV;
2352         }
2353         ret = sysfs_emit(page, "%s\n",
2354                         tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
2355         mutex_unlock(&tpg->tv_tpg_mutex);
2356
2357         return ret;
2358 }
2359
2360 static ssize_t vhost_scsi_tpg_nexus_store(struct config_item *item,
2361                 const char *page, size_t count)
2362 {
2363         struct se_portal_group *se_tpg = to_tpg(item);
2364         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2365                                 struct vhost_scsi_tpg, se_tpg);
2366         struct vhost_scsi_tport *tport_wwn = tpg->tport;
2367         unsigned char i_port[VHOST_SCSI_NAMELEN], *ptr, *port_ptr;
2368         int ret;
2369         /*
2370          * Shutdown the active I_T nexus if 'NULL' is passed..
2371          */
2372         if (!strncmp(page, "NULL", 4)) {
2373                 ret = vhost_scsi_drop_nexus(tpg);
2374                 return (!ret) ? count : ret;
2375         }
2376         /*
2377          * Otherwise make sure the passed virtual Initiator port WWN matches
2378          * the fabric protocol_id set in vhost_scsi_make_tport(), and call
2379          * vhost_scsi_make_nexus().
2380          */
2381         if (strlen(page) >= VHOST_SCSI_NAMELEN) {
2382                 pr_err("Emulated NAA Sas Address: %s, exceeds"
2383                                 " max: %d\n", page, VHOST_SCSI_NAMELEN);
2384                 return -EINVAL;
2385         }
2386         snprintf(&i_port[0], VHOST_SCSI_NAMELEN, "%s", page);
2387
2388         ptr = strstr(i_port, "naa.");
2389         if (ptr) {
2390                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
2391                         pr_err("Passed SAS Initiator Port %s does not"
2392                                 " match target port protoid: %s\n", i_port,
2393                                 vhost_scsi_dump_proto_id(tport_wwn));
2394                         return -EINVAL;
2395                 }
2396                 port_ptr = &i_port[0];
2397                 goto check_newline;
2398         }
2399         ptr = strstr(i_port, "fc.");
2400         if (ptr) {
2401                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
2402                         pr_err("Passed FCP Initiator Port %s does not"
2403                                 " match target port protoid: %s\n", i_port,
2404                                 vhost_scsi_dump_proto_id(tport_wwn));
2405                         return -EINVAL;
2406                 }
2407                 port_ptr = &i_port[3]; /* Skip over "fc." */
2408                 goto check_newline;
2409         }
2410         ptr = strstr(i_port, "iqn.");
2411         if (ptr) {
2412                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
2413                         pr_err("Passed iSCSI Initiator Port %s does not"
2414                                 " match target port protoid: %s\n", i_port,
2415                                 vhost_scsi_dump_proto_id(tport_wwn));
2416                         return -EINVAL;
2417                 }
2418                 port_ptr = &i_port[0];
2419                 goto check_newline;
2420         }
2421         pr_err("Unable to locate prefix for emulated Initiator Port:"
2422                         " %s\n", i_port);
2423         return -EINVAL;
2424         /*
2425          * Clear any trailing newline for the NAA WWN
2426          */
2427 check_newline:
2428         if (i_port[strlen(i_port)-1] == '\n')
2429                 i_port[strlen(i_port)-1] = '\0';
2430
2431         ret = vhost_scsi_make_nexus(tpg, port_ptr);
2432         if (ret < 0)
2433                 return ret;
2434
2435         return count;
2436 }
2437
2438 CONFIGFS_ATTR(vhost_scsi_tpg_, nexus);
2439
2440 static struct configfs_attribute *vhost_scsi_tpg_attrs[] = {
2441         &vhost_scsi_tpg_attr_nexus,
2442         NULL,
2443 };
2444
2445 static struct se_portal_group *
2446 vhost_scsi_make_tpg(struct se_wwn *wwn, const char *name)
2447 {
2448         struct vhost_scsi_tport *tport = container_of(wwn,
2449                         struct vhost_scsi_tport, tport_wwn);
2450
2451         struct vhost_scsi_tpg *tpg;
2452         u16 tpgt;
2453         int ret;
2454
2455         if (strstr(name, "tpgt_") != name)
2456                 return ERR_PTR(-EINVAL);
2457         if (kstrtou16(name + 5, 10, &tpgt) || tpgt >= VHOST_SCSI_MAX_TARGET)
2458                 return ERR_PTR(-EINVAL);
2459
2460         tpg = kzalloc(sizeof(*tpg), GFP_KERNEL);
2461         if (!tpg) {
2462                 pr_err("Unable to allocate struct vhost_scsi_tpg");
2463                 return ERR_PTR(-ENOMEM);
2464         }
2465         mutex_init(&tpg->tv_tpg_mutex);
2466         INIT_LIST_HEAD(&tpg->tv_tpg_list);
2467         tpg->tport = tport;
2468         tpg->tport_tpgt = tpgt;
2469
2470         ret = core_tpg_register(wwn, &tpg->se_tpg, tport->tport_proto_id);
2471         if (ret < 0) {
2472                 kfree(tpg);
2473                 return NULL;
2474         }
2475         mutex_lock(&vhost_scsi_mutex);
2476         list_add_tail(&tpg->tv_tpg_list, &vhost_scsi_list);
2477         mutex_unlock(&vhost_scsi_mutex);
2478
2479         return &tpg->se_tpg;
2480 }
2481
2482 static void vhost_scsi_drop_tpg(struct se_portal_group *se_tpg)
2483 {
2484         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2485                                 struct vhost_scsi_tpg, se_tpg);
2486
2487         mutex_lock(&vhost_scsi_mutex);
2488         list_del(&tpg->tv_tpg_list);
2489         mutex_unlock(&vhost_scsi_mutex);
2490         /*
2491          * Release the virtual I_T Nexus for this vhost TPG
2492          */
2493         vhost_scsi_drop_nexus(tpg);
2494         /*
2495          * Deregister the se_tpg from TCM..
2496          */
2497         core_tpg_deregister(se_tpg);
2498         kfree(tpg);
2499 }
2500
2501 static struct se_wwn *
2502 vhost_scsi_make_tport(struct target_fabric_configfs *tf,
2503                      struct config_group *group,
2504                      const char *name)
2505 {
2506         struct vhost_scsi_tport *tport;
2507         char *ptr;
2508         u64 wwpn = 0;
2509         int off = 0;
2510
2511         /* if (vhost_scsi_parse_wwn(name, &wwpn, 1) < 0)
2512                 return ERR_PTR(-EINVAL); */
2513
2514         tport = kzalloc(sizeof(*tport), GFP_KERNEL);
2515         if (!tport) {
2516                 pr_err("Unable to allocate struct vhost_scsi_tport");
2517                 return ERR_PTR(-ENOMEM);
2518         }
2519         tport->tport_wwpn = wwpn;
2520         /*
2521          * Determine the emulated Protocol Identifier and Target Port Name
2522          * based on the incoming configfs directory name.
2523          */
2524         ptr = strstr(name, "naa.");
2525         if (ptr) {
2526                 tport->tport_proto_id = SCSI_PROTOCOL_SAS;
2527                 goto check_len;
2528         }
2529         ptr = strstr(name, "fc.");
2530         if (ptr) {
2531                 tport->tport_proto_id = SCSI_PROTOCOL_FCP;
2532                 off = 3; /* Skip over "fc." */
2533                 goto check_len;
2534         }
2535         ptr = strstr(name, "iqn.");
2536         if (ptr) {
2537                 tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
2538                 goto check_len;
2539         }
2540
2541         pr_err("Unable to locate prefix for emulated Target Port:"
2542                         " %s\n", name);
2543         kfree(tport);
2544         return ERR_PTR(-EINVAL);
2545
2546 check_len:
2547         if (strlen(name) >= VHOST_SCSI_NAMELEN) {
2548                 pr_err("Emulated %s Address: %s, exceeds"
2549                         " max: %d\n", name, vhost_scsi_dump_proto_id(tport),
2550                         VHOST_SCSI_NAMELEN);
2551                 kfree(tport);
2552                 return ERR_PTR(-EINVAL);
2553         }
2554         snprintf(&tport->tport_name[0], VHOST_SCSI_NAMELEN, "%s", &name[off]);
2555
2556         pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target"
2557                 " %s Address: %s\n", vhost_scsi_dump_proto_id(tport), name);
2558
2559         return &tport->tport_wwn;
2560 }
2561
2562 static void vhost_scsi_drop_tport(struct se_wwn *wwn)
2563 {
2564         struct vhost_scsi_tport *tport = container_of(wwn,
2565                                 struct vhost_scsi_tport, tport_wwn);
2566
2567         pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target"
2568                 " %s Address: %s\n", vhost_scsi_dump_proto_id(tport),
2569                 tport->tport_name);
2570
2571         kfree(tport);
2572 }
2573
2574 static ssize_t
2575 vhost_scsi_wwn_version_show(struct config_item *item, char *page)
2576 {
2577         return sysfs_emit(page, "TCM_VHOST fabric module %s on %s/%s"
2578                 "on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
2579                 utsname()->machine);
2580 }
2581
2582 CONFIGFS_ATTR_RO(vhost_scsi_wwn_, version);
2583
2584 static struct configfs_attribute *vhost_scsi_wwn_attrs[] = {
2585         &vhost_scsi_wwn_attr_version,
2586         NULL,
2587 };
2588
2589 static const struct target_core_fabric_ops vhost_scsi_ops = {
2590         .module                         = THIS_MODULE,
2591         .fabric_name                    = "vhost",
2592         .max_data_sg_nents              = VHOST_SCSI_PREALLOC_SGLS,
2593         .tpg_get_wwn                    = vhost_scsi_get_fabric_wwn,
2594         .tpg_get_tag                    = vhost_scsi_get_tpgt,
2595         .tpg_check_demo_mode            = vhost_scsi_check_true,
2596         .tpg_check_demo_mode_cache      = vhost_scsi_check_true,
2597         .tpg_check_prot_fabric_only     = vhost_scsi_check_prot_fabric_only,
2598         .release_cmd                    = vhost_scsi_release_cmd,
2599         .check_stop_free                = vhost_scsi_check_stop_free,
2600         .sess_get_initiator_sid         = NULL,
2601         .write_pending                  = vhost_scsi_write_pending,
2602         .queue_data_in                  = vhost_scsi_queue_data_in,
2603         .queue_status                   = vhost_scsi_queue_status,
2604         .queue_tm_rsp                   = vhost_scsi_queue_tm_rsp,
2605         .aborted_task                   = vhost_scsi_aborted_task,
2606         /*
2607          * Setup callers for generic logic in target_core_fabric_configfs.c
2608          */
2609         .fabric_make_wwn                = vhost_scsi_make_tport,
2610         .fabric_drop_wwn                = vhost_scsi_drop_tport,
2611         .fabric_make_tpg                = vhost_scsi_make_tpg,
2612         .fabric_drop_tpg                = vhost_scsi_drop_tpg,
2613         .fabric_post_link               = vhost_scsi_port_link,
2614         .fabric_pre_unlink              = vhost_scsi_port_unlink,
2615
2616         .tfc_wwn_attrs                  = vhost_scsi_wwn_attrs,
2617         .tfc_tpg_base_attrs             = vhost_scsi_tpg_attrs,
2618         .tfc_tpg_attrib_attrs           = vhost_scsi_tpg_attrib_attrs,
2619
2620         .default_submit_type            = TARGET_QUEUE_SUBMIT,
2621         .direct_submit_supp             = 1,
2622 };
2623
2624 static int __init vhost_scsi_init(void)
2625 {
2626         int ret = -ENOMEM;
2627
2628         pr_debug("TCM_VHOST fabric module %s on %s/%s"
2629                 " on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
2630                 utsname()->machine);
2631
2632         ret = vhost_scsi_register();
2633         if (ret < 0)
2634                 goto out;
2635
2636         ret = target_register_template(&vhost_scsi_ops);
2637         if (ret < 0)
2638                 goto out_vhost_scsi_deregister;
2639
2640         return 0;
2641
2642 out_vhost_scsi_deregister:
2643         vhost_scsi_deregister();
2644 out:
2645         return ret;
2646 };
2647
2648 static void vhost_scsi_exit(void)
2649 {
2650         target_unregister_template(&vhost_scsi_ops);
2651         vhost_scsi_deregister();
2652 };
2653
2654 MODULE_DESCRIPTION("VHOST_SCSI series fabric driver");
2655 MODULE_ALIAS("tcm_vhost");
2656 MODULE_LICENSE("GPL");
2657 module_init(vhost_scsi_init);
2658 module_exit(vhost_scsi_exit);