drivers/vhost/scsi.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*******************************************************************************
   3  * Vhost kernel TCM fabric driver for virtio SCSI initiators
   4  *
   5  * (C) Copyright 2010-2013 Datera, Inc.
   6  * (C) Copyright 2010-2012 IBM Corp.
   7  *
   8  * Authors: Nicholas A. Bellinger <nab@daterainc.com>
   9  *          Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
  10  ****************************************************************************/
  11
  12 #include <linux/module.h>
  13 #include <linux/moduleparam.h>
  14 #include <generated/utsrelease.h>
  15 #include <linux/utsname.h>
  16 #include <linux/init.h>
  17 #include <linux/slab.h>
  18 #include <linux/kthread.h>
  19 #include <linux/types.h>
  20 #include <linux/string.h>
  21 #include <linux/configfs.h>
  22 #include <linux/ctype.h>
  23 #include <linux/compat.h>
  24 #include <linux/eventfd.h>
  25 #include <linux/fs.h>
  26 #include <linux/vmalloc.h>
  27 #include <linux/miscdevice.h>
  28 #include <asm/unaligned.h>
  29 #include <scsi/scsi_common.h>
  30 #include <scsi/scsi_proto.h>
  31 #include <target/target_core_base.h>
  32 #include <target/target_core_fabric.h>
  33 #include <linux/vhost.h>
  34 #include <linux/virtio_scsi.h>
  35 #include <linux/llist.h>
  36 #include <linux/bitmap.h>
  37
  38 #include "vhost.h"
  39
  40 #define VHOST_SCSI_VERSION  "v0.1"
  41 #define VHOST_SCSI_NAMELEN 256
  42 #define VHOST_SCSI_MAX_CDB_SIZE 32
  43 #define VHOST_SCSI_PREALLOC_SGLS 2048
  44 #define VHOST_SCSI_PREALLOC_UPAGES 2048
  45 #define VHOST_SCSI_PREALLOC_PROT_SGLS 2048
  46
  47 /* Max number of requests before requeueing the job.
  48  * Using this limit prevents one virtqueue from starving others with
  49  * request.
  50  */
  51 #define VHOST_SCSI_WEIGHT 256
  52
  53 struct vhost_scsi_inflight {
  54         /* Wait for the flush operation to finish */
  55         struct completion comp;
  56         /* Refcount for the inflight reqs */
  57         struct kref kref;
  58 };
  59
  60 struct vhost_scsi_cmd {
  61         /* Descriptor from vhost_get_vq_desc() for virt_queue segment */
  62         int tvc_vq_desc;
  63         /* virtio-scsi initiator task attribute */
  64         int tvc_task_attr;
  65         /* virtio-scsi response incoming iovecs */
  66         int tvc_in_iovs;
  67         /* virtio-scsi initiator data direction */
  68         enum dma_data_direction tvc_data_direction;
  69         /* Expected data transfer length from virtio-scsi header */
  70         u32 tvc_exp_data_len;
  71         /* The Tag from include/linux/virtio_scsi.h:struct virtio_scsi_cmd_req */
  72         u64 tvc_tag;
  73         /* The number of scatterlists associated with this cmd */
  74         u32 tvc_sgl_count;
  75         u32 tvc_prot_sgl_count;
  76         /* Saved unpacked SCSI LUN for vhost_scsi_target_queue_cmd() */
  77         u32 tvc_lun;
  78         /* Pointer to the SGL formatted memory from virtio-scsi */
  79         struct scatterlist *tvc_sgl;
  80         struct scatterlist *tvc_prot_sgl;
  81         struct page **tvc_upages;
  82         /* Pointer to response header iovec */
  83         struct iovec *tvc_resp_iov;
  84         /* Pointer to vhost_scsi for our device */
  85         struct vhost_scsi *tvc_vhost;
  86         /* Pointer to vhost_virtqueue for the cmd */
  87         struct vhost_virtqueue *tvc_vq;
  88         /* Pointer to vhost nexus memory */
  89         struct vhost_scsi_nexus *tvc_nexus;
  90         /* The TCM I/O descriptor that is accessed via container_of() */
  91         struct se_cmd tvc_se_cmd;
  92         /* Copy of the incoming SCSI command descriptor block (CDB) */
  93         unsigned char tvc_cdb[VHOST_SCSI_MAX_CDB_SIZE];
  94         /* Sense buffer that will be mapped into outgoing status */
  95         unsigned char tvc_sense_buf[TRANSPORT_SENSE_BUFFER];
  96         /* Completed commands list, serviced from vhost worker thread */
  97         struct llist_node tvc_completion_list;
  98         /* Used to track inflight cmd */
  99         struct vhost_scsi_inflight *inflight;
 100 };
 101
 102 struct vhost_scsi_nexus {
 103         /* Pointer to TCM session for I_T Nexus */
 104         struct se_session *tvn_se_sess;
 105 };
 106
 107 struct vhost_scsi_tpg {
 108         /* Vhost port target portal group tag for TCM */
 109         u16 tport_tpgt;
 110         /* Used to track number of TPG Port/Lun Links wrt to explict I_T Nexus shutdown */
 111         int tv_tpg_port_count;
 112         /* Used for vhost_scsi device reference to tpg_nexus, protected by tv_tpg_mutex */
 113         int tv_tpg_vhost_count;
 114         /* Used for enabling T10-PI with legacy devices */
 115         int tv_fabric_prot_type;
 116         /* list for vhost_scsi_list */
 117         struct list_head tv_tpg_list;
 118         /* Used to protect access for tpg_nexus */
 119         struct mutex tv_tpg_mutex;
 120         /* Pointer to the TCM VHost I_T Nexus for this TPG endpoint */
 121         struct vhost_scsi_nexus *tpg_nexus;
 122         /* Pointer back to vhost_scsi_tport */
 123         struct vhost_scsi_tport *tport;
 124         /* Returned by vhost_scsi_make_tpg() */
 125         struct se_portal_group se_tpg;
 126         /* Pointer back to vhost_scsi, protected by tv_tpg_mutex */
 127         struct vhost_scsi *vhost_scsi;
 128 };
 129
 130 struct vhost_scsi_tport {
 131         /* SCSI protocol the tport is providing */
 132         u8 tport_proto_id;
 133         /* Binary World Wide unique Port Name for Vhost Target port */
 134         u64 tport_wwpn;
 135         /* ASCII formatted WWPN for Vhost Target port */
 136         char tport_name[VHOST_SCSI_NAMELEN];
 137         /* Returned by vhost_scsi_make_tport() */
 138         struct se_wwn tport_wwn;
 139 };
 140
 141 struct vhost_scsi_evt {
 142         /* event to be sent to guest */
 143         struct virtio_scsi_event event;
 144         /* event list, serviced from vhost worker thread */
 145         struct llist_node list;
 146 };
 147
 148 enum {
 149         VHOST_SCSI_VQ_CTL = 0,
 150         VHOST_SCSI_VQ_EVT = 1,
 151         VHOST_SCSI_VQ_IO = 2,
 152 };
 153
 154 /* Note: can't set VIRTIO_F_VERSION_1 yet, since that implies ANY_LAYOUT. */
 155 enum {
 156         VHOST_SCSI_FEATURES = VHOST_FEATURES | (1ULL << VIRTIO_SCSI_F_HOTPLUG) |
 157                                                (1ULL << VIRTIO_SCSI_F_T10_PI)
 158 };
 159
 160 #define VHOST_SCSI_MAX_TARGET   256
 161 #define VHOST_SCSI_MAX_IO_VQ    1024
 162 #define VHOST_SCSI_MAX_EVENT    128
 163
 164 static unsigned vhost_scsi_max_io_vqs = 128;
 165 module_param_named(max_io_vqs, vhost_scsi_max_io_vqs, uint, 0644);
 166 MODULE_PARM_DESC(max_io_vqs, "Set the max number of IO virtqueues a vhost scsi device can support. The default is 128. The max is 1024.");
 167
 168 struct vhost_scsi_virtqueue {
 169         struct vhost_virtqueue vq;
 170         /*
 171          * Reference counting for inflight reqs, used for flush operation. At
 172          * each time, one reference tracks new commands submitted, while we
 173          * wait for another one to reach 0.
 174          */
 175         struct vhost_scsi_inflight inflights[2];
 176         /*
 177          * Indicate current inflight in use, protected by vq->mutex.
 178          * Writers must also take dev mutex and flush under it.
 179          */
 180         int inflight_idx;
 181         struct vhost_scsi_cmd *scsi_cmds;
 182         struct sbitmap scsi_tags;
 183         int max_cmds;
 184 };
 185
 186 struct vhost_scsi {
 187         /* Protected by vhost_scsi->dev.mutex */
 188         struct vhost_scsi_tpg **vs_tpg;
 189         char vs_vhost_wwpn[TRANSPORT_IQN_LEN];
 190
 191         struct vhost_dev dev;
 192         struct vhost_scsi_virtqueue *vqs;
 193         unsigned long *compl_bitmap;
 194         struct vhost_scsi_inflight **old_inflight;
 195
 196         struct vhost_work vs_completion_work; /* cmd completion work item */
 197         struct llist_head vs_completion_list; /* cmd completion queue */
 198
 199         struct vhost_work vs_event_work; /* evt injection work item */
 200         struct llist_head vs_event_list; /* evt injection queue */
 201
 202         bool vs_events_missed; /* any missed events, protected by vq->mutex */
 203         int vs_events_nr; /* num of pending events, protected by vq->mutex */
 204 };
 205
 206 struct vhost_scsi_tmf {
 207         struct vhost_work vwork;
 208         struct vhost_scsi *vhost;
 209         struct vhost_scsi_virtqueue *svq;
 210
 211         struct se_cmd se_cmd;
 212         u8 scsi_resp;
 213         struct vhost_scsi_inflight *inflight;
 214         struct iovec resp_iov;
 215         int in_iovs;
 216         int vq_desc;
 217 };
 218
 219 /*
 220  * Context for processing request and control queue operations.
 221  */
 222 struct vhost_scsi_ctx {
 223         int head;
 224         unsigned int out, in;
 225         size_t req_size, rsp_size;
 226         size_t out_size, in_size;
 227         u8 *target, *lunp;
 228         void *req;
 229         struct iov_iter out_iter;
 230 };
 231
 232 /*
 233  * Global mutex to protect vhost_scsi TPG list for vhost IOCTLs and LIO
 234  * configfs management operations.
 235  */
 236 static DEFINE_MUTEX(vhost_scsi_mutex);
 237 static LIST_HEAD(vhost_scsi_list);
 238
 239 static void vhost_scsi_done_inflight(struct kref *kref)
 240 {
 241         struct vhost_scsi_inflight *inflight;
 242
 243         inflight = container_of(kref, struct vhost_scsi_inflight, kref);
 244         complete(&inflight->comp);
 245 }
 246
 247 static void vhost_scsi_init_inflight(struct vhost_scsi *vs,
 248                                     struct vhost_scsi_inflight *old_inflight[])
 249 {
 250         struct vhost_scsi_inflight *new_inflight;
 251         struct vhost_virtqueue *vq;
 252         int idx, i;
 253
 254         for (i = 0; i < vs->dev.nvqs;  i++) {
 255                 vq = &vs->vqs[i].vq;
 256
 257                 mutex_lock(&vq->mutex);
 258
 259                 /* store old infight */
 260                 idx = vs->vqs[i].inflight_idx;
 261                 if (old_inflight)
 262                         old_inflight[i] = &vs->vqs[i].inflights[idx];
 263
 264                 /* setup new infight */
 265                 vs->vqs[i].inflight_idx = idx ^ 1;
 266                 new_inflight = &vs->vqs[i].inflights[idx ^ 1];
 267                 kref_init(&new_inflight->kref);
 268                 init_completion(&new_inflight->comp);
 269
 270                 mutex_unlock(&vq->mutex);
 271         }
 272 }
 273
 274 static struct vhost_scsi_inflight *
 275 vhost_scsi_get_inflight(struct vhost_virtqueue *vq)
 276 {
 277         struct vhost_scsi_inflight *inflight;
 278         struct vhost_scsi_virtqueue *svq;
 279
 280         svq = container_of(vq, struct vhost_scsi_virtqueue, vq);
 281         inflight = &svq->inflights[svq->inflight_idx];
 282         kref_get(&inflight->kref);
 283
 284         return inflight;
 285 }
 286
 287 static void vhost_scsi_put_inflight(struct vhost_scsi_inflight *inflight)
 288 {
 289         kref_put(&inflight->kref, vhost_scsi_done_inflight);
 290 }
 291
 292 static int vhost_scsi_check_true(struct se_portal_group *se_tpg)
 293 {
 294         return 1;
 295 }
 296
 297 static char *vhost_scsi_get_fabric_wwn(struct se_portal_group *se_tpg)
 298 {
 299         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 300                                 struct vhost_scsi_tpg, se_tpg);
 301         struct vhost_scsi_tport *tport = tpg->tport;
 302
 303         return &tport->tport_name[0];
 304 }
 305
 306 static u16 vhost_scsi_get_tpgt(struct se_portal_group *se_tpg)
 307 {
 308         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 309                                 struct vhost_scsi_tpg, se_tpg);
 310         return tpg->tport_tpgt;
 311 }
 312
 313 static int vhost_scsi_check_prot_fabric_only(struct se_portal_group *se_tpg)
 314 {
 315         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
 316                                 struct vhost_scsi_tpg, se_tpg);
 317
 318         return tpg->tv_fabric_prot_type;
 319 }
 320
 321 static void vhost_scsi_release_cmd_res(struct se_cmd *se_cmd)
 322 {
 323         struct vhost_scsi_cmd *tv_cmd = container_of(se_cmd,
 324                                 struct vhost_scsi_cmd, tvc_se_cmd);
 325         struct vhost_scsi_virtqueue *svq = container_of(tv_cmd->tvc_vq,
 326                                 struct vhost_scsi_virtqueue, vq);
 327         struct vhost_scsi_inflight *inflight = tv_cmd->inflight;
 328         int i;
 329
 330         if (tv_cmd->tvc_sgl_count) {
 331                 for (i = 0; i < tv_cmd->tvc_sgl_count; i++)
 332                         put_page(sg_page(&tv_cmd->tvc_sgl[i]));
 333         }
 334         if (tv_cmd->tvc_prot_sgl_count) {
 335                 for (i = 0; i < tv_cmd->tvc_prot_sgl_count; i++)
 336                         put_page(sg_page(&tv_cmd->tvc_prot_sgl[i]));
 337         }
 338
 339         sbitmap_clear_bit(&svq->scsi_tags, se_cmd->map_tag);
 340         vhost_scsi_put_inflight(inflight);
 341 }
 342
 343 static void vhost_scsi_release_tmf_res(struct vhost_scsi_tmf *tmf)
 344 {
 345         struct vhost_scsi_inflight *inflight = tmf->inflight;
 346
 347         kfree(tmf);
 348         vhost_scsi_put_inflight(inflight);
 349 }
 350
 351 static void vhost_scsi_release_cmd(struct se_cmd *se_cmd)
 352 {
 353         if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB) {
 354                 struct vhost_scsi_tmf *tmf = container_of(se_cmd,
 355                                         struct vhost_scsi_tmf, se_cmd);
 356
 357                 vhost_work_queue(&tmf->vhost->dev, &tmf->vwork);
 358         } else {
 359                 struct vhost_scsi_cmd *cmd = container_of(se_cmd,
 360                                         struct vhost_scsi_cmd, tvc_se_cmd);
 361                 struct vhost_scsi *vs = cmd->tvc_vhost;
 362
 363                 llist_add(&cmd->tvc_completion_list, &vs->vs_completion_list);
 364                 vhost_work_queue(&vs->dev, &vs->vs_completion_work);
 365         }
 366 }
 367
 368 static int vhost_scsi_write_pending(struct se_cmd *se_cmd)
 369 {
 370         /* Go ahead and process the write immediately */
 371         target_execute_cmd(se_cmd);
 372         return 0;
 373 }
 374
 375 static int vhost_scsi_queue_data_in(struct se_cmd *se_cmd)
 376 {
 377         transport_generic_free_cmd(se_cmd, 0);
 378         return 0;
 379 }
 380
 381 static int vhost_scsi_queue_status(struct se_cmd *se_cmd)
 382 {
 383         transport_generic_free_cmd(se_cmd, 0);
 384         return 0;
 385 }
 386
 387 static void vhost_scsi_queue_tm_rsp(struct se_cmd *se_cmd)
 388 {
 389         struct vhost_scsi_tmf *tmf = container_of(se_cmd, struct vhost_scsi_tmf,
 390                                                   se_cmd);
 391
 392         tmf->scsi_resp = se_cmd->se_tmr_req->response;
 393         transport_generic_free_cmd(&tmf->se_cmd, 0);
 394 }
 395
 396 static void vhost_scsi_aborted_task(struct se_cmd *se_cmd)
 397 {
 398         return;
 399 }
 400
 401 static void vhost_scsi_free_evt(struct vhost_scsi *vs, struct vhost_scsi_evt *evt)
 402 {
 403         vs->vs_events_nr--;
 404         kfree(evt);
 405 }
 406
 407 static struct vhost_scsi_evt *
 408 vhost_scsi_allocate_evt(struct vhost_scsi *vs,
 409                        u32 event, u32 reason)
 410 {
 411         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 412         struct vhost_scsi_evt *evt;
 413
 414         if (vs->vs_events_nr > VHOST_SCSI_MAX_EVENT) {
 415                 vs->vs_events_missed = true;
 416                 return NULL;
 417         }
 418
 419         evt = kzalloc(sizeof(*evt), GFP_KERNEL);
 420         if (!evt) {
 421                 vq_err(vq, "Failed to allocate vhost_scsi_evt\n");
 422                 vs->vs_events_missed = true;
 423                 return NULL;
 424         }
 425
 426         evt->event.event = cpu_to_vhost32(vq, event);
 427         evt->event.reason = cpu_to_vhost32(vq, reason);
 428         vs->vs_events_nr++;
 429
 430         return evt;
 431 }
 432
 433 static int vhost_scsi_check_stop_free(struct se_cmd *se_cmd)
 434 {
 435         return target_put_sess_cmd(se_cmd);
 436 }
 437
 438 static void
 439 vhost_scsi_do_evt_work(struct vhost_scsi *vs, struct vhost_scsi_evt *evt)
 440 {
 441         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 442         struct virtio_scsi_event *event = &evt->event;
 443         struct virtio_scsi_event __user *eventp;
 444         unsigned out, in;
 445         int head, ret;
 446
 447         if (!vhost_vq_get_backend(vq)) {
 448                 vs->vs_events_missed = true;
 449                 return;
 450         }
 451
 452 again:
 453         vhost_disable_notify(&vs->dev, vq);
 454         head = vhost_get_vq_desc(vq, vq->iov,
 455                         ARRAY_SIZE(vq->iov), &out, &in,
 456                         NULL, NULL);
 457         if (head < 0) {
 458                 vs->vs_events_missed = true;
 459                 return;
 460         }
 461         if (head == vq->num) {
 462                 if (vhost_enable_notify(&vs->dev, vq))
 463                         goto again;
 464                 vs->vs_events_missed = true;
 465                 return;
 466         }
 467
 468         if ((vq->iov[out].iov_len != sizeof(struct virtio_scsi_event))) {
 469                 vq_err(vq, "Expecting virtio_scsi_event, got %zu bytes\n",
 470                                 vq->iov[out].iov_len);
 471                 vs->vs_events_missed = true;
 472                 return;
 473         }
 474
 475         if (vs->vs_events_missed) {
 476                 event->event |= cpu_to_vhost32(vq, VIRTIO_SCSI_T_EVENTS_MISSED);
 477                 vs->vs_events_missed = false;
 478         }
 479
 480         eventp = vq->iov[out].iov_base;
 481         ret = __copy_to_user(eventp, event, sizeof(*event));
 482         if (!ret)
 483                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 484         else
 485                 vq_err(vq, "Faulted on vhost_scsi_send_event\n");
 486 }
 487
 488 static void vhost_scsi_evt_work(struct vhost_work *work)
 489 {
 490         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 491                                         vs_event_work);
 492         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
 493         struct vhost_scsi_evt *evt, *t;
 494         struct llist_node *llnode;
 495
 496         mutex_lock(&vq->mutex);
 497         llnode = llist_del_all(&vs->vs_event_list);
 498         llist_for_each_entry_safe(evt, t, llnode, list) {
 499                 vhost_scsi_do_evt_work(vs, evt);
 500                 vhost_scsi_free_evt(vs, evt);
 501         }
 502         mutex_unlock(&vq->mutex);
 503 }
 504
 505 /* Fill in status and signal that we are done processing this command
 506  *
 507  * This is scheduled in the vhost work queue so we are called with the owner
 508  * process mm and can access the vring.
 509  */
 510 static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
 511 {
 512         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 513                                         vs_completion_work);
 514         struct virtio_scsi_cmd_resp v_rsp;
 515         struct vhost_scsi_cmd *cmd, *t;
 516         struct llist_node *llnode;
 517         struct se_cmd *se_cmd;
 518         struct iov_iter iov_iter;
 519         int ret, vq;
 520
 521         bitmap_zero(vs->compl_bitmap, vs->dev.nvqs);
 522         llnode = llist_del_all(&vs->vs_completion_list);
 523         llist_for_each_entry_safe(cmd, t, llnode, tvc_completion_list) {
 524                 se_cmd = &cmd->tvc_se_cmd;
 525
 526                 pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__,
 527                         cmd, se_cmd->residual_count, se_cmd->scsi_status);
 528
 529                 memset(&v_rsp, 0, sizeof(v_rsp));
 530                 v_rsp.resid = cpu_to_vhost32(cmd->tvc_vq, se_cmd->residual_count);
 531                 /* TODO is status_qualifier field needed? */
 532                 v_rsp.status = se_cmd->scsi_status;
 533                 v_rsp.sense_len = cpu_to_vhost32(cmd->tvc_vq,
 534                                                  se_cmd->scsi_sense_length);
 535                 memcpy(v_rsp.sense, cmd->tvc_sense_buf,
 536                        se_cmd->scsi_sense_length);
 537
 538                 iov_iter_init(&iov_iter, ITER_DEST, cmd->tvc_resp_iov,
 539                               cmd->tvc_in_iovs, sizeof(v_rsp));
 540                 ret = copy_to_iter(&v_rsp, sizeof(v_rsp), &iov_iter);
 541                 if (likely(ret == sizeof(v_rsp))) {
 542                         struct vhost_scsi_virtqueue *q;
 543                         vhost_add_used(cmd->tvc_vq, cmd->tvc_vq_desc, 0);
 544                         q = container_of(cmd->tvc_vq, struct vhost_scsi_virtqueue, vq);
 545                         vq = q - vs->vqs;
 546                         __set_bit(vq, vs->compl_bitmap);
 547                 } else
 548                         pr_err("Faulted on virtio_scsi_cmd_resp\n");
 549
 550                 vhost_scsi_release_cmd_res(se_cmd);
 551         }
 552
 553         vq = -1;
 554         while ((vq = find_next_bit(vs->compl_bitmap, vs->dev.nvqs, vq + 1))
 555                 < vs->dev.nvqs)
 556                 vhost_signal(&vs->dev, &vs->vqs[vq].vq);
 557 }
 558
 559 static struct vhost_scsi_cmd *
 560 vhost_scsi_get_cmd(struct vhost_virtqueue *vq, struct vhost_scsi_tpg *tpg,
 561                    unsigned char *cdb, u64 scsi_tag, u16 lun, u8 task_attr,
 562                    u32 exp_data_len, int data_direction)
 563 {
 564         struct vhost_scsi_virtqueue *svq = container_of(vq,
 565                                         struct vhost_scsi_virtqueue, vq);
 566         struct vhost_scsi_cmd *cmd;
 567         struct vhost_scsi_nexus *tv_nexus;
 568         struct scatterlist *sg, *prot_sg;
 569         struct iovec *tvc_resp_iov;
 570         struct page **pages;
 571         int tag;
 572
 573         tv_nexus = tpg->tpg_nexus;
 574         if (!tv_nexus) {
 575                 pr_err("Unable to locate active struct vhost_scsi_nexus\n");
 576                 return ERR_PTR(-EIO);
 577         }
 578
 579         tag = sbitmap_get(&svq->scsi_tags);
 580         if (tag < 0) {
 581                 pr_err("Unable to obtain tag for vhost_scsi_cmd\n");
 582                 return ERR_PTR(-ENOMEM);
 583         }
 584
 585         cmd = &svq->scsi_cmds[tag];
 586         sg = cmd->tvc_sgl;
 587         prot_sg = cmd->tvc_prot_sgl;
 588         pages = cmd->tvc_upages;
 589         tvc_resp_iov = cmd->tvc_resp_iov;
 590         memset(cmd, 0, sizeof(*cmd));
 591         cmd->tvc_sgl = sg;
 592         cmd->tvc_prot_sgl = prot_sg;
 593         cmd->tvc_upages = pages;
 594         cmd->tvc_se_cmd.map_tag = tag;
 595         cmd->tvc_tag = scsi_tag;
 596         cmd->tvc_lun = lun;
 597         cmd->tvc_task_attr = task_attr;
 598         cmd->tvc_exp_data_len = exp_data_len;
 599         cmd->tvc_data_direction = data_direction;
 600         cmd->tvc_nexus = tv_nexus;
 601         cmd->inflight = vhost_scsi_get_inflight(vq);
 602         cmd->tvc_resp_iov = tvc_resp_iov;
 603
 604         memcpy(cmd->tvc_cdb, cdb, VHOST_SCSI_MAX_CDB_SIZE);
 605
 606         return cmd;
 607 }
 608
 609 /*
 610  * Map a user memory range into a scatterlist
 611  *
 612  * Returns the number of scatterlist entries used or -errno on error.
 613  */
 614 static int
 615 vhost_scsi_map_to_sgl(struct vhost_scsi_cmd *cmd,
 616                       struct iov_iter *iter,
 617                       struct scatterlist *sgl,
 618                       bool write)
 619 {
 620         struct page **pages = cmd->tvc_upages;
 621         struct scatterlist *sg = sgl;
 622         ssize_t bytes;
 623         size_t offset;
 624         unsigned int npages = 0;
 625
 626         bytes = iov_iter_get_pages2(iter, pages, LONG_MAX,
 627                                 VHOST_SCSI_PREALLOC_UPAGES, &offset);
 628         /* No pages were pinned */
 629         if (bytes <= 0)
 630                 return bytes < 0 ? bytes : -EFAULT;
 631
 632         while (bytes) {
 633                 unsigned n = min_t(unsigned, PAGE_SIZE - offset, bytes);
 634                 sg_set_page(sg++, pages[npages++], n, offset);
 635                 bytes -= n;
 636                 offset = 0;
 637         }
 638         return npages;
 639 }
 640
 641 static int
 642 vhost_scsi_calc_sgls(struct iov_iter *iter, size_t bytes, int max_sgls)
 643 {
 644         int sgl_count = 0;
 645
 646         if (!iter || !iter_iov(iter)) {
 647                 pr_err("%s: iter->iov is NULL, but expected bytes: %zu"
 648                        " present\n", __func__, bytes);
 649                 return -EINVAL;
 650         }
 651
 652         sgl_count = iov_iter_npages(iter, 0xffff);
 653         if (sgl_count > max_sgls) {
 654                 pr_err("%s: requested sgl_count: %d exceeds pre-allocated"
 655                        " max_sgls: %d\n", __func__, sgl_count, max_sgls);
 656                 return -EINVAL;
 657         }
 658         return sgl_count;
 659 }
 660
 661 static int
 662 vhost_scsi_iov_to_sgl(struct vhost_scsi_cmd *cmd, bool write,
 663                       struct iov_iter *iter,
 664                       struct scatterlist *sg, int sg_count)
 665 {
 666         struct scatterlist *p = sg;
 667         int ret;
 668
 669         while (iov_iter_count(iter)) {
 670                 ret = vhost_scsi_map_to_sgl(cmd, iter, sg, write);
 671                 if (ret < 0) {
 672                         while (p < sg) {
 673                                 struct page *page = sg_page(p++);
 674                                 if (page)
 675                                         put_page(page);
 676                         }
 677                         return ret;
 678                 }
 679                 sg += ret;
 680         }
 681         return 0;
 682 }
 683
 684 static int
 685 vhost_scsi_mapal(struct vhost_scsi_cmd *cmd,
 686                  size_t prot_bytes, struct iov_iter *prot_iter,
 687                  size_t data_bytes, struct iov_iter *data_iter)
 688 {
 689         int sgl_count, ret;
 690         bool write = (cmd->tvc_data_direction == DMA_FROM_DEVICE);
 691
 692         if (prot_bytes) {
 693                 sgl_count = vhost_scsi_calc_sgls(prot_iter, prot_bytes,
 694                                                  VHOST_SCSI_PREALLOC_PROT_SGLS);
 695                 if (sgl_count < 0)
 696                         return sgl_count;
 697
 698                 sg_init_table(cmd->tvc_prot_sgl, sgl_count);
 699                 cmd->tvc_prot_sgl_count = sgl_count;
 700                 pr_debug("%s prot_sg %p prot_sgl_count %u\n", __func__,
 701                          cmd->tvc_prot_sgl, cmd->tvc_prot_sgl_count);
 702
 703                 ret = vhost_scsi_iov_to_sgl(cmd, write, prot_iter,
 704                                             cmd->tvc_prot_sgl,
 705                                             cmd->tvc_prot_sgl_count);
 706                 if (ret < 0) {
 707                         cmd->tvc_prot_sgl_count = 0;
 708                         return ret;
 709                 }
 710         }
 711         sgl_count = vhost_scsi_calc_sgls(data_iter, data_bytes,
 712                                          VHOST_SCSI_PREALLOC_SGLS);
 713         if (sgl_count < 0)
 714                 return sgl_count;
 715
 716         sg_init_table(cmd->tvc_sgl, sgl_count);
 717         cmd->tvc_sgl_count = sgl_count;
 718         pr_debug("%s data_sg %p data_sgl_count %u\n", __func__,
 719                   cmd->tvc_sgl, cmd->tvc_sgl_count);
 720
 721         ret = vhost_scsi_iov_to_sgl(cmd, write, data_iter,
 722                                     cmd->tvc_sgl, cmd->tvc_sgl_count);
 723         if (ret < 0) {
 724                 cmd->tvc_sgl_count = 0;
 725                 return ret;
 726         }
 727         return 0;
 728 }
 729
 730 static int vhost_scsi_to_tcm_attr(int attr)
 731 {
 732         switch (attr) {
 733         case VIRTIO_SCSI_S_SIMPLE:
 734                 return TCM_SIMPLE_TAG;
 735         case VIRTIO_SCSI_S_ORDERED:
 736                 return TCM_ORDERED_TAG;
 737         case VIRTIO_SCSI_S_HEAD:
 738                 return TCM_HEAD_TAG;
 739         case VIRTIO_SCSI_S_ACA:
 740                 return TCM_ACA_TAG;
 741         default:
 742                 break;
 743         }
 744         return TCM_SIMPLE_TAG;
 745 }
 746
 747 static void vhost_scsi_target_queue_cmd(struct vhost_scsi_cmd *cmd)
 748 {
 749         struct se_cmd *se_cmd = &cmd->tvc_se_cmd;
 750         struct vhost_scsi_nexus *tv_nexus;
 751         struct scatterlist *sg_ptr, *sg_prot_ptr = NULL;
 752
 753         /* FIXME: BIDI operation */
 754         if (cmd->tvc_sgl_count) {
 755                 sg_ptr = cmd->tvc_sgl;
 756
 757                 if (cmd->tvc_prot_sgl_count)
 758                         sg_prot_ptr = cmd->tvc_prot_sgl;
 759                 else
 760                         se_cmd->prot_pto = true;
 761         } else {
 762                 sg_ptr = NULL;
 763         }
 764         tv_nexus = cmd->tvc_nexus;
 765
 766         se_cmd->tag = 0;
 767         target_init_cmd(se_cmd, tv_nexus->tvn_se_sess, &cmd->tvc_sense_buf[0],
 768                         cmd->tvc_lun, cmd->tvc_exp_data_len,
 769                         vhost_scsi_to_tcm_attr(cmd->tvc_task_attr),
 770                         cmd->tvc_data_direction, TARGET_SCF_ACK_KREF);
 771
 772         if (target_submit_prep(se_cmd, cmd->tvc_cdb, sg_ptr,
 773                                cmd->tvc_sgl_count, NULL, 0, sg_prot_ptr,
 774                                cmd->tvc_prot_sgl_count, GFP_KERNEL))
 775                 return;
 776
 777         target_queue_submission(se_cmd);
 778 }
 779
 780 static void
 781 vhost_scsi_send_bad_target(struct vhost_scsi *vs,
 782                            struct vhost_virtqueue *vq,
 783                            int head, unsigned out)
 784 {
 785         struct virtio_scsi_cmd_resp __user *resp;
 786         struct virtio_scsi_cmd_resp rsp;
 787         int ret;
 788
 789         memset(&rsp, 0, sizeof(rsp));
 790         rsp.response = VIRTIO_SCSI_S_BAD_TARGET;
 791         resp = vq->iov[out].iov_base;
 792         ret = __copy_to_user(resp, &rsp, sizeof(rsp));
 793         if (!ret)
 794                 vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 795         else
 796                 pr_err("Faulted on virtio_scsi_cmd_resp\n");
 797 }
 798
 799 static int
 800 vhost_scsi_get_desc(struct vhost_scsi *vs, struct vhost_virtqueue *vq,
 801                     struct vhost_scsi_ctx *vc)
 802 {
 803         int ret = -ENXIO;
 804
 805         vc->head = vhost_get_vq_desc(vq, vq->iov,
 806                                      ARRAY_SIZE(vq->iov), &vc->out, &vc->in,
 807                                      NULL, NULL);
 808
 809         pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n",
 810                  vc->head, vc->out, vc->in);
 811
 812         /* On error, stop handling until the next kick. */
 813         if (unlikely(vc->head < 0))
 814                 goto done;
 815
 816         /* Nothing new?  Wait for eventfd to tell us they refilled. */
 817         if (vc->head == vq->num) {
 818                 if (unlikely(vhost_enable_notify(&vs->dev, vq))) {
 819                         vhost_disable_notify(&vs->dev, vq);
 820                         ret = -EAGAIN;
 821                 }
 822                 goto done;
 823         }
 824
 825         /*
 826          * Get the size of request and response buffers.
 827          * FIXME: Not correct for BIDI operation
 828          */
 829         vc->out_size = iov_length(vq->iov, vc->out);
 830         vc->in_size = iov_length(&vq->iov[vc->out], vc->in);
 831
 832         /*
 833          * Copy over the virtio-scsi request header, which for a
 834          * ANY_LAYOUT enabled guest may span multiple iovecs, or a
 835          * single iovec may contain both the header + outgoing
 836          * WRITE payloads.
 837          *
 838          * copy_from_iter() will advance out_iter, so that it will
 839          * point at the start of the outgoing WRITE payload, if
 840          * DMA_TO_DEVICE is set.
 841          */
 842         iov_iter_init(&vc->out_iter, ITER_SOURCE, vq->iov, vc->out, vc->out_size);
 843         ret = 0;
 844
 845 done:
 846         return ret;
 847 }
 848
 849 static int
 850 vhost_scsi_chk_size(struct vhost_virtqueue *vq, struct vhost_scsi_ctx *vc)
 851 {
 852         if (unlikely(vc->in_size < vc->rsp_size)) {
 853                 vq_err(vq,
 854                        "Response buf too small, need min %zu bytes got %zu",
 855                        vc->rsp_size, vc->in_size);
 856                 return -EINVAL;
 857         } else if (unlikely(vc->out_size < vc->req_size)) {
 858                 vq_err(vq,
 859                        "Request buf too small, need min %zu bytes got %zu",
 860                        vc->req_size, vc->out_size);
 861                 return -EIO;
 862         }
 863
 864         return 0;
 865 }
 866
 867 static int
 868 vhost_scsi_get_req(struct vhost_virtqueue *vq, struct vhost_scsi_ctx *vc,
 869                    struct vhost_scsi_tpg **tpgp)
 870 {
 871         int ret = -EIO;
 872
 873         if (unlikely(!copy_from_iter_full(vc->req, vc->req_size,
 874                                           &vc->out_iter))) {
 875                 vq_err(vq, "Faulted on copy_from_iter_full\n");
 876         } else if (unlikely(*vc->lunp != 1)) {
 877                 /* virtio-scsi spec requires byte 0 of the lun to be 1 */
 878                 vq_err(vq, "Illegal virtio-scsi lun: %u\n", *vc->lunp);
 879         } else {
 880                 struct vhost_scsi_tpg **vs_tpg, *tpg;
 881
 882                 vs_tpg = vhost_vq_get_backend(vq);      /* validated at handler entry */
 883
 884                 tpg = READ_ONCE(vs_tpg[*vc->target]);
 885                 if (unlikely(!tpg)) {
 886                         vq_err(vq, "Target 0x%x does not exist\n", *vc->target);
 887                 } else {
 888                         if (tpgp)
 889                                 *tpgp = tpg;
 890                         ret = 0;
 891                 }
 892         }
 893
 894         return ret;
 895 }
 896
 897 static u16 vhost_buf_to_lun(u8 *lun_buf)
 898 {
 899         return ((lun_buf[2] << 8) | lun_buf[3]) & 0x3FFF;
 900 }
 901
 902 static void
 903 vhost_scsi_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
 904 {
 905         struct vhost_scsi_tpg **vs_tpg, *tpg;
 906         struct virtio_scsi_cmd_req v_req;
 907         struct virtio_scsi_cmd_req_pi v_req_pi;
 908         struct vhost_scsi_ctx vc;
 909         struct vhost_scsi_cmd *cmd;
 910         struct iov_iter in_iter, prot_iter, data_iter;
 911         u64 tag;
 912         u32 exp_data_len, data_direction;
 913         int ret, prot_bytes, i, c = 0;
 914         u16 lun;
 915         u8 task_attr;
 916         bool t10_pi = vhost_has_feature(vq, VIRTIO_SCSI_F_T10_PI);
 917         void *cdb;
 918
 919         mutex_lock(&vq->mutex);
 920         /*
 921          * We can handle the vq only after the endpoint is setup by calling the
 922          * VHOST_SCSI_SET_ENDPOINT ioctl.
 923          */
 924         vs_tpg = vhost_vq_get_backend(vq);
 925         if (!vs_tpg)
 926                 goto out;
 927
 928         memset(&vc, 0, sizeof(vc));
 929         vc.rsp_size = sizeof(struct virtio_scsi_cmd_resp);
 930
 931         vhost_disable_notify(&vs->dev, vq);
 932
 933         do {
 934                 ret = vhost_scsi_get_desc(vs, vq, &vc);
 935                 if (ret)
 936                         goto err;
 937
 938                 /*
 939                  * Setup pointers and values based upon different virtio-scsi
 940                  * request header if T10_PI is enabled in KVM guest.
 941                  */
 942                 if (t10_pi) {
 943                         vc.req = &v_req_pi;
 944                         vc.req_size = sizeof(v_req_pi);
 945                         vc.lunp = &v_req_pi.lun[0];
 946                         vc.target = &v_req_pi.lun[1];
 947                 } else {
 948                         vc.req = &v_req;
 949                         vc.req_size = sizeof(v_req);
 950                         vc.lunp = &v_req.lun[0];
 951                         vc.target = &v_req.lun[1];
 952                 }
 953
 954                 /*
 955                  * Validate the size of request and response buffers.
 956                  * Check for a sane response buffer so we can report
 957                  * early errors back to the guest.
 958                  */
 959                 ret = vhost_scsi_chk_size(vq, &vc);
 960                 if (ret)
 961                         goto err;
 962
 963                 ret = vhost_scsi_get_req(vq, &vc, &tpg);
 964                 if (ret)
 965                         goto err;
 966
 967                 ret = -EIO;     /* bad target on any error from here on */
 968
 969                 /*
 970                  * Determine data_direction by calculating the total outgoing
 971                  * iovec sizes + incoming iovec sizes vs. virtio-scsi request +
 972                  * response headers respectively.
 973                  *
 974                  * For DMA_TO_DEVICE this is out_iter, which is already pointing
 975                  * to the right place.
 976                  *
 977                  * For DMA_FROM_DEVICE, the iovec will be just past the end
 978                  * of the virtio-scsi response header in either the same
 979                  * or immediately following iovec.
 980                  *
 981                  * Any associated T10_PI bytes for the outgoing / incoming
 982                  * payloads are included in calculation of exp_data_len here.
 983                  */
 984                 prot_bytes = 0;
 985
 986                 if (vc.out_size > vc.req_size) {
 987                         data_direction = DMA_TO_DEVICE;
 988                         exp_data_len = vc.out_size - vc.req_size;
 989                         data_iter = vc.out_iter;
 990                 } else if (vc.in_size > vc.rsp_size) {
 991                         data_direction = DMA_FROM_DEVICE;
 992                         exp_data_len = vc.in_size - vc.rsp_size;
 993
 994                         iov_iter_init(&in_iter, ITER_DEST, &vq->iov[vc.out], vc.in,
 995                                       vc.rsp_size + exp_data_len);
 996                         iov_iter_advance(&in_iter, vc.rsp_size);
 997                         data_iter = in_iter;
 998                 } else {
 999                         data_direction = DMA_NONE;
1000                         exp_data_len = 0;
1001                 }
1002                 /*
1003                  * If T10_PI header + payload is present, setup prot_iter values
1004                  * and recalculate data_iter for vhost_scsi_mapal() mapping to
1005                  * host scatterlists via get_user_pages_fast().
1006                  */
1007                 if (t10_pi) {
1008                         if (v_req_pi.pi_bytesout) {
1009                                 if (data_direction != DMA_TO_DEVICE) {
1010                                         vq_err(vq, "Received non zero pi_bytesout,"
1011                                                 " but wrong data_direction\n");
1012                                         goto err;
1013                                 }
1014                                 prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesout);
1015                         } else if (v_req_pi.pi_bytesin) {
1016                                 if (data_direction != DMA_FROM_DEVICE) {
1017                                         vq_err(vq, "Received non zero pi_bytesin,"
1018                                                 " but wrong data_direction\n");
1019                                         goto err;
1020                                 }
1021                                 prot_bytes = vhost32_to_cpu(vq, v_req_pi.pi_bytesin);
1022                         }
1023                         /*
1024                          * Set prot_iter to data_iter and truncate it to
1025                          * prot_bytes, and advance data_iter past any
1026                          * preceeding prot_bytes that may be present.
1027                          *
1028                          * Also fix up the exp_data_len to reflect only the
1029                          * actual data payload length.
1030                          */
1031                         if (prot_bytes) {
1032                                 exp_data_len -= prot_bytes;
1033                                 prot_iter = data_iter;
1034                                 iov_iter_truncate(&prot_iter, prot_bytes);
1035                                 iov_iter_advance(&data_iter, prot_bytes);
1036                         }
1037                         tag = vhost64_to_cpu(vq, v_req_pi.tag);
1038                         task_attr = v_req_pi.task_attr;
1039                         cdb = &v_req_pi.cdb[0];
1040                         lun = vhost_buf_to_lun(v_req_pi.lun);
1041                 } else {
1042                         tag = vhost64_to_cpu(vq, v_req.tag);
1043                         task_attr = v_req.task_attr;
1044                         cdb = &v_req.cdb[0];
1045                         lun = vhost_buf_to_lun(v_req.lun);
1046                 }
1047                 /*
1048                  * Check that the received CDB size does not exceeded our
1049                  * hardcoded max for vhost-scsi, then get a pre-allocated
1050                  * cmd descriptor for the new virtio-scsi tag.
1051                  *
1052                  * TODO what if cdb was too small for varlen cdb header?
1053                  */
1054                 if (unlikely(scsi_command_size(cdb) > VHOST_SCSI_MAX_CDB_SIZE)) {
1055                         vq_err(vq, "Received SCSI CDB with command_size: %d that"
1056                                 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
1057                                 scsi_command_size(cdb), VHOST_SCSI_MAX_CDB_SIZE);
1058                                 goto err;
1059                 }
1060                 cmd = vhost_scsi_get_cmd(vq, tpg, cdb, tag, lun, task_attr,
1061                                          exp_data_len + prot_bytes,
1062                                          data_direction);
1063                 if (IS_ERR(cmd)) {
1064                         vq_err(vq, "vhost_scsi_get_cmd failed %ld\n",
1065                                PTR_ERR(cmd));
1066                         goto err;
1067                 }
1068                 cmd->tvc_vhost = vs;
1069                 cmd->tvc_vq = vq;
1070                 for (i = 0; i < vc.in ; i++)
1071                         cmd->tvc_resp_iov[i] = vq->iov[vc.out + i];
1072                 cmd->tvc_in_iovs = vc.in;
1073
1074                 pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n",
1075                          cmd->tvc_cdb[0], cmd->tvc_lun);
1076                 pr_debug("cmd: %p exp_data_len: %d, prot_bytes: %d data_direction:"
1077                          " %d\n", cmd, exp_data_len, prot_bytes, data_direction);
1078
1079                 if (data_direction != DMA_NONE) {
1080                         if (unlikely(vhost_scsi_mapal(cmd, prot_bytes,
1081                                                       &prot_iter, exp_data_len,
1082                                                       &data_iter))) {
1083                                 vq_err(vq, "Failed to map iov to sgl\n");
1084                                 vhost_scsi_release_cmd_res(&cmd->tvc_se_cmd);
1085                                 goto err;
1086                         }
1087                 }
1088                 /*
1089                  * Save the descriptor from vhost_get_vq_desc() to be used to
1090                  * complete the virtio-scsi request in TCM callback context via
1091                  * vhost_scsi_queue_data_in() and vhost_scsi_queue_status()
1092                  */
1093                 cmd->tvc_vq_desc = vc.head;
1094                 vhost_scsi_target_queue_cmd(cmd);
1095                 ret = 0;
1096 err:
1097                 /*
1098                  * ENXIO:  No more requests, or read error, wait for next kick
1099                  * EINVAL: Invalid response buffer, drop the request
1100                  * EIO:    Respond with bad target
1101                  * EAGAIN: Pending request
1102                  */
1103                 if (ret == -ENXIO)
1104                         break;
1105                 else if (ret == -EIO)
1106                         vhost_scsi_send_bad_target(vs, vq, vc.head, vc.out);
1107         } while (likely(!vhost_exceeds_weight(vq, ++c, 0)));
1108 out:
1109         mutex_unlock(&vq->mutex);
1110 }
1111
1112 static void
1113 vhost_scsi_send_tmf_resp(struct vhost_scsi *vs, struct vhost_virtqueue *vq,
1114                          int in_iovs, int vq_desc, struct iovec *resp_iov,
1115                          int tmf_resp_code)
1116 {
1117         struct virtio_scsi_ctrl_tmf_resp rsp;
1118         struct iov_iter iov_iter;
1119         int ret;
1120
1121         pr_debug("%s\n", __func__);
1122         memset(&rsp, 0, sizeof(rsp));
1123         rsp.response = tmf_resp_code;
1124
1125         iov_iter_init(&iov_iter, ITER_DEST, resp_iov, in_iovs, sizeof(rsp));
1126
1127         ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter);
1128         if (likely(ret == sizeof(rsp)))
1129                 vhost_add_used_and_signal(&vs->dev, vq, vq_desc, 0);
1130         else
1131                 pr_err("Faulted on virtio_scsi_ctrl_tmf_resp\n");
1132 }
1133
1134 static void vhost_scsi_tmf_resp_work(struct vhost_work *work)
1135 {
1136         struct vhost_scsi_tmf *tmf = container_of(work, struct vhost_scsi_tmf,
1137                                                   vwork);
1138         int resp_code;
1139
1140         if (tmf->scsi_resp == TMR_FUNCTION_COMPLETE)
1141                 resp_code = VIRTIO_SCSI_S_FUNCTION_SUCCEEDED;
1142         else
1143                 resp_code = VIRTIO_SCSI_S_FUNCTION_REJECTED;
1144
1145         vhost_scsi_send_tmf_resp(tmf->vhost, &tmf->svq->vq, tmf->in_iovs,
1146                                  tmf->vq_desc, &tmf->resp_iov, resp_code);
1147         vhost_scsi_release_tmf_res(tmf);
1148 }
1149
1150 static void
1151 vhost_scsi_handle_tmf(struct vhost_scsi *vs, struct vhost_scsi_tpg *tpg,
1152                       struct vhost_virtqueue *vq,
1153                       struct virtio_scsi_ctrl_tmf_req *vtmf,
1154                       struct vhost_scsi_ctx *vc)
1155 {
1156         struct vhost_scsi_virtqueue *svq = container_of(vq,
1157                                         struct vhost_scsi_virtqueue, vq);
1158         struct vhost_scsi_tmf *tmf;
1159
1160         if (vhost32_to_cpu(vq, vtmf->subtype) !=
1161             VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET)
1162                 goto send_reject;
1163
1164         if (!tpg->tpg_nexus || !tpg->tpg_nexus->tvn_se_sess) {
1165                 pr_err("Unable to locate active struct vhost_scsi_nexus for LUN RESET.\n");
1166                 goto send_reject;
1167         }
1168
1169         tmf = kzalloc(sizeof(*tmf), GFP_KERNEL);
1170         if (!tmf)
1171                 goto send_reject;
1172
1173         vhost_work_init(&tmf->vwork, vhost_scsi_tmf_resp_work);
1174         tmf->vhost = vs;
1175         tmf->svq = svq;
1176         tmf->resp_iov = vq->iov[vc->out];
1177         tmf->vq_desc = vc->head;
1178         tmf->in_iovs = vc->in;
1179         tmf->inflight = vhost_scsi_get_inflight(vq);
1180
1181         if (target_submit_tmr(&tmf->se_cmd, tpg->tpg_nexus->tvn_se_sess, NULL,
1182                               vhost_buf_to_lun(vtmf->lun), NULL,
1183                               TMR_LUN_RESET, GFP_KERNEL, 0,
1184                               TARGET_SCF_ACK_KREF) < 0) {
1185                 vhost_scsi_release_tmf_res(tmf);
1186                 goto send_reject;
1187         }
1188
1189         return;
1190
1191 send_reject:
1192         vhost_scsi_send_tmf_resp(vs, vq, vc->in, vc->head, &vq->iov[vc->out],
1193                                  VIRTIO_SCSI_S_FUNCTION_REJECTED);
1194 }
1195
1196 static void
1197 vhost_scsi_send_an_resp(struct vhost_scsi *vs,
1198                         struct vhost_virtqueue *vq,
1199                         struct vhost_scsi_ctx *vc)
1200 {
1201         struct virtio_scsi_ctrl_an_resp rsp;
1202         struct iov_iter iov_iter;
1203         int ret;
1204
1205         pr_debug("%s\n", __func__);
1206         memset(&rsp, 0, sizeof(rsp));   /* event_actual = 0 */
1207         rsp.response = VIRTIO_SCSI_S_OK;
1208
1209         iov_iter_init(&iov_iter, ITER_DEST, &vq->iov[vc->out], vc->in, sizeof(rsp));
1210
1211         ret = copy_to_iter(&rsp, sizeof(rsp), &iov_iter);
1212         if (likely(ret == sizeof(rsp)))
1213                 vhost_add_used_and_signal(&vs->dev, vq, vc->head, 0);
1214         else
1215                 pr_err("Faulted on virtio_scsi_ctrl_an_resp\n");
1216 }
1217
1218 static void
1219 vhost_scsi_ctl_handle_vq(struct vhost_scsi *vs, struct vhost_virtqueue *vq)
1220 {
1221         struct vhost_scsi_tpg *tpg;
1222         union {
1223                 __virtio32 type;
1224                 struct virtio_scsi_ctrl_an_req an;
1225                 struct virtio_scsi_ctrl_tmf_req tmf;
1226         } v_req;
1227         struct vhost_scsi_ctx vc;
1228         size_t typ_size;
1229         int ret, c = 0;
1230
1231         mutex_lock(&vq->mutex);
1232         /*
1233          * We can handle the vq only after the endpoint is setup by calling the
1234          * VHOST_SCSI_SET_ENDPOINT ioctl.
1235          */
1236         if (!vhost_vq_get_backend(vq))
1237                 goto out;
1238
1239         memset(&vc, 0, sizeof(vc));
1240
1241         vhost_disable_notify(&vs->dev, vq);
1242
1243         do {
1244                 ret = vhost_scsi_get_desc(vs, vq, &vc);
1245                 if (ret)
1246                         goto err;
1247
1248                 /*
1249                  * Get the request type first in order to setup
1250                  * other parameters dependent on the type.
1251                  */
1252                 vc.req = &v_req.type;
1253                 typ_size = sizeof(v_req.type);
1254
1255                 if (unlikely(!copy_from_iter_full(vc.req, typ_size,
1256                                                   &vc.out_iter))) {
1257                         vq_err(vq, "Faulted on copy_from_iter tmf type\n");
1258                         /*
1259                          * The size of the response buffer depends on the
1260                          * request type and must be validated against it.
1261                          * Since the request type is not known, don't send
1262                          * a response.
1263                          */
1264                         continue;
1265                 }
1266
1267                 switch (vhost32_to_cpu(vq, v_req.type)) {
1268                 case VIRTIO_SCSI_T_TMF:
1269                         vc.req = &v_req.tmf;
1270                         vc.req_size = sizeof(struct virtio_scsi_ctrl_tmf_req);
1271                         vc.rsp_size = sizeof(struct virtio_scsi_ctrl_tmf_resp);
1272                         vc.lunp = &v_req.tmf.lun[0];
1273                         vc.target = &v_req.tmf.lun[1];
1274                         break;
1275                 case VIRTIO_SCSI_T_AN_QUERY:
1276                 case VIRTIO_SCSI_T_AN_SUBSCRIBE:
1277                         vc.req = &v_req.an;
1278                         vc.req_size = sizeof(struct virtio_scsi_ctrl_an_req);
1279                         vc.rsp_size = sizeof(struct virtio_scsi_ctrl_an_resp);
1280                         vc.lunp = &v_req.an.lun[0];
1281                         vc.target = NULL;
1282                         break;
1283                 default:
1284                         vq_err(vq, "Unknown control request %d", v_req.type);
1285                         continue;
1286                 }
1287
1288                 /*
1289                  * Validate the size of request and response buffers.
1290                  * Check for a sane response buffer so we can report
1291                  * early errors back to the guest.
1292                  */
1293                 ret = vhost_scsi_chk_size(vq, &vc);
1294                 if (ret)
1295                         goto err;
1296
1297                 /*
1298                  * Get the rest of the request now that its size is known.
1299                  */
1300                 vc.req += typ_size;
1301                 vc.req_size -= typ_size;
1302
1303                 ret = vhost_scsi_get_req(vq, &vc, &tpg);
1304                 if (ret)
1305                         goto err;
1306
1307                 if (v_req.type == VIRTIO_SCSI_T_TMF)
1308                         vhost_scsi_handle_tmf(vs, tpg, vq, &v_req.tmf, &vc);
1309                 else
1310                         vhost_scsi_send_an_resp(vs, vq, &vc);
1311 err:
1312                 /*
1313                  * ENXIO:  No more requests, or read error, wait for next kick
1314                  * EINVAL: Invalid response buffer, drop the request
1315                  * EIO:    Respond with bad target
1316                  * EAGAIN: Pending request
1317                  */
1318                 if (ret == -ENXIO)
1319                         break;
1320                 else if (ret == -EIO)
1321                         vhost_scsi_send_bad_target(vs, vq, vc.head, vc.out);
1322         } while (likely(!vhost_exceeds_weight(vq, ++c, 0)));
1323 out:
1324         mutex_unlock(&vq->mutex);
1325 }
1326
1327 static void vhost_scsi_ctl_handle_kick(struct vhost_work *work)
1328 {
1329         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1330                                                 poll.work);
1331         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1332
1333         pr_debug("%s: The handling func for control queue.\n", __func__);
1334         vhost_scsi_ctl_handle_vq(vs, vq);
1335 }
1336
1337 static void
1338 vhost_scsi_send_evt(struct vhost_scsi *vs,
1339                    struct vhost_scsi_tpg *tpg,
1340                    struct se_lun *lun,
1341                    u32 event,
1342                    u32 reason)
1343 {
1344         struct vhost_scsi_evt *evt;
1345
1346         evt = vhost_scsi_allocate_evt(vs, event, reason);
1347         if (!evt)
1348                 return;
1349
1350         if (tpg && lun) {
1351                 /* TODO: share lun setup code with virtio-scsi.ko */
1352                 /*
1353                  * Note: evt->event is zeroed when we allocate it and
1354                  * lun[4-7] need to be zero according to virtio-scsi spec.
1355                  */
1356                 evt->event.lun[0] = 0x01;
1357                 evt->event.lun[1] = tpg->tport_tpgt;
1358                 if (lun->unpacked_lun >= 256)
1359                         evt->event.lun[2] = lun->unpacked_lun >> 8 | 0x40 ;
1360                 evt->event.lun[3] = lun->unpacked_lun & 0xFF;
1361         }
1362
1363         llist_add(&evt->list, &vs->vs_event_list);
1364         vhost_work_queue(&vs->dev, &vs->vs_event_work);
1365 }
1366
1367 static void vhost_scsi_evt_handle_kick(struct vhost_work *work)
1368 {
1369         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1370                                                 poll.work);
1371         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1372
1373         mutex_lock(&vq->mutex);
1374         if (!vhost_vq_get_backend(vq))
1375                 goto out;
1376
1377         if (vs->vs_events_missed)
1378                 vhost_scsi_send_evt(vs, NULL, NULL, VIRTIO_SCSI_T_NO_EVENT, 0);
1379 out:
1380         mutex_unlock(&vq->mutex);
1381 }
1382
1383 static void vhost_scsi_handle_kick(struct vhost_work *work)
1384 {
1385         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
1386                                                 poll.work);
1387         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
1388
1389         vhost_scsi_handle_vq(vs, vq);
1390 }
1391
1392 /* Callers must hold dev mutex */
1393 static void vhost_scsi_flush(struct vhost_scsi *vs)
1394 {
1395         int i;
1396
1397         /* Init new inflight and remember the old inflight */
1398         vhost_scsi_init_inflight(vs, vs->old_inflight);
1399
1400         /*
1401          * The inflight->kref was initialized to 1. We decrement it here to
1402          * indicate the start of the flush operation so that it will reach 0
1403          * when all the reqs are finished.
1404          */
1405         for (i = 0; i < vs->dev.nvqs; i++)
1406                 kref_put(&vs->old_inflight[i]->kref, vhost_scsi_done_inflight);
1407
1408         /* Flush both the vhost poll and vhost work */
1409         vhost_dev_flush(&vs->dev);
1410
1411         /* Wait for all reqs issued before the flush to be finished */
1412         for (i = 0; i < vs->dev.nvqs; i++)
1413                 wait_for_completion(&vs->old_inflight[i]->comp);
1414 }
1415
1416 static void vhost_scsi_destroy_vq_cmds(struct vhost_virtqueue *vq)
1417 {
1418         struct vhost_scsi_virtqueue *svq = container_of(vq,
1419                                         struct vhost_scsi_virtqueue, vq);
1420         struct vhost_scsi_cmd *tv_cmd;
1421         unsigned int i;
1422
1423         if (!svq->scsi_cmds)
1424                 return;
1425
1426         for (i = 0; i < svq->max_cmds; i++) {
1427                 tv_cmd = &svq->scsi_cmds[i];
1428
1429                 kfree(tv_cmd->tvc_sgl);
1430                 kfree(tv_cmd->tvc_prot_sgl);
1431                 kfree(tv_cmd->tvc_upages);
1432                 kfree(tv_cmd->tvc_resp_iov);
1433         }
1434
1435         sbitmap_free(&svq->scsi_tags);
1436         kfree(svq->scsi_cmds);
1437         svq->scsi_cmds = NULL;
1438 }
1439
1440 static int vhost_scsi_setup_vq_cmds(struct vhost_virtqueue *vq, int max_cmds)
1441 {
1442         struct vhost_scsi_virtqueue *svq = container_of(vq,
1443                                         struct vhost_scsi_virtqueue, vq);
1444         struct vhost_scsi_cmd *tv_cmd;
1445         unsigned int i;
1446
1447         if (svq->scsi_cmds)
1448                 return 0;
1449
1450         if (sbitmap_init_node(&svq->scsi_tags, max_cmds, -1, GFP_KERNEL,
1451                               NUMA_NO_NODE, false, true))
1452                 return -ENOMEM;
1453         svq->max_cmds = max_cmds;
1454
1455         svq->scsi_cmds = kcalloc(max_cmds, sizeof(*tv_cmd), GFP_KERNEL);
1456         if (!svq->scsi_cmds) {
1457                 sbitmap_free(&svq->scsi_tags);
1458                 return -ENOMEM;
1459         }
1460
1461         for (i = 0; i < max_cmds; i++) {
1462                 tv_cmd = &svq->scsi_cmds[i];
1463
1464                 tv_cmd->tvc_sgl = kcalloc(VHOST_SCSI_PREALLOC_SGLS,
1465                                           sizeof(struct scatterlist),
1466                                           GFP_KERNEL);
1467                 if (!tv_cmd->tvc_sgl) {
1468                         pr_err("Unable to allocate tv_cmd->tvc_sgl\n");
1469                         goto out;
1470                 }
1471
1472                 tv_cmd->tvc_upages = kcalloc(VHOST_SCSI_PREALLOC_UPAGES,
1473                                              sizeof(struct page *),
1474                                              GFP_KERNEL);
1475                 if (!tv_cmd->tvc_upages) {
1476                         pr_err("Unable to allocate tv_cmd->tvc_upages\n");
1477                         goto out;
1478                 }
1479
1480                 tv_cmd->tvc_resp_iov = kcalloc(UIO_MAXIOV,
1481                                                sizeof(struct iovec),
1482                                                GFP_KERNEL);
1483                 if (!tv_cmd->tvc_resp_iov) {
1484                         pr_err("Unable to allocate tv_cmd->tvc_resp_iov\n");
1485                         goto out;
1486                 }
1487
1488                 tv_cmd->tvc_prot_sgl = kcalloc(VHOST_SCSI_PREALLOC_PROT_SGLS,
1489                                                sizeof(struct scatterlist),
1490                                                GFP_KERNEL);
1491                 if (!tv_cmd->tvc_prot_sgl) {
1492                         pr_err("Unable to allocate tv_cmd->tvc_prot_sgl\n");
1493                         goto out;
1494                 }
1495         }
1496         return 0;
1497 out:
1498         vhost_scsi_destroy_vq_cmds(vq);
1499         return -ENOMEM;
1500 }
1501
1502 /*
1503  * Called from vhost_scsi_ioctl() context to walk the list of available
1504  * vhost_scsi_tpg with an active struct vhost_scsi_nexus
1505  *
1506  *  The lock nesting rule is:
1507  *    vs->dev.mutex -> vhost_scsi_mutex -> tpg->tv_tpg_mutex -> vq->mutex
1508  */
1509 static int
1510 vhost_scsi_set_endpoint(struct vhost_scsi *vs,
1511                         struct vhost_scsi_target *t)
1512 {
1513         struct se_portal_group *se_tpg;
1514         struct vhost_scsi_tport *tv_tport;
1515         struct vhost_scsi_tpg *tpg;
1516         struct vhost_scsi_tpg **vs_tpg;
1517         struct vhost_virtqueue *vq;
1518         int index, ret, i, len;
1519         bool match = false;
1520
1521         mutex_lock(&vs->dev.mutex);
1522
1523         /* Verify that ring has been setup correctly. */
1524         for (index = 0; index < vs->dev.nvqs; ++index) {
1525                 /* Verify that ring has been setup correctly. */
1526                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1527                         ret = -EFAULT;
1528                         goto out;
1529                 }
1530         }
1531
1532         len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET;
1533         vs_tpg = kzalloc(len, GFP_KERNEL);
1534         if (!vs_tpg) {
1535                 ret = -ENOMEM;
1536                 goto out;
1537         }
1538         if (vs->vs_tpg)
1539                 memcpy(vs_tpg, vs->vs_tpg, len);
1540
1541         mutex_lock(&vhost_scsi_mutex);
1542         list_for_each_entry(tpg, &vhost_scsi_list, tv_tpg_list) {
1543                 mutex_lock(&tpg->tv_tpg_mutex);
1544                 if (!tpg->tpg_nexus) {
1545                         mutex_unlock(&tpg->tv_tpg_mutex);
1546                         continue;
1547                 }
1548                 if (tpg->tv_tpg_vhost_count != 0) {
1549                         mutex_unlock(&tpg->tv_tpg_mutex);
1550                         continue;
1551                 }
1552                 tv_tport = tpg->tport;
1553
1554                 if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1555                         if (vs->vs_tpg && vs->vs_tpg[tpg->tport_tpgt]) {
1556                                 mutex_unlock(&tpg->tv_tpg_mutex);
1557                                 mutex_unlock(&vhost_scsi_mutex);
1558                                 ret = -EEXIST;
1559                                 goto undepend;
1560                         }
1561                         /*
1562                          * In order to ensure individual vhost-scsi configfs
1563                          * groups cannot be removed while in use by vhost ioctl,
1564                          * go ahead and take an explicit se_tpg->tpg_group.cg_item
1565                          * dependency now.
1566                          */
1567                         se_tpg = &tpg->se_tpg;
1568                         ret = target_depend_item(&se_tpg->tpg_group.cg_item);
1569                         if (ret) {
1570                                 pr_warn("target_depend_item() failed: %d\n", ret);
1571                                 mutex_unlock(&tpg->tv_tpg_mutex);
1572                                 mutex_unlock(&vhost_scsi_mutex);
1573                                 goto undepend;
1574                         }
1575                         tpg->tv_tpg_vhost_count++;
1576                         tpg->vhost_scsi = vs;
1577                         vs_tpg[tpg->tport_tpgt] = tpg;
1578                         match = true;
1579                 }
1580                 mutex_unlock(&tpg->tv_tpg_mutex);
1581         }
1582         mutex_unlock(&vhost_scsi_mutex);
1583
1584         if (match) {
1585                 memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
1586                        sizeof(vs->vs_vhost_wwpn));
1587
1588                 for (i = VHOST_SCSI_VQ_IO; i < vs->dev.nvqs; i++) {
1589                         vq = &vs->vqs[i].vq;
1590                         if (!vhost_vq_is_setup(vq))
1591                                 continue;
1592
1593                         ret = vhost_scsi_setup_vq_cmds(vq, vq->num);
1594                         if (ret)
1595                                 goto destroy_vq_cmds;
1596                 }
1597
1598                 for (i = 0; i < vs->dev.nvqs; i++) {
1599                         vq = &vs->vqs[i].vq;
1600                         mutex_lock(&vq->mutex);
1601                         vhost_vq_set_backend(vq, vs_tpg);
1602                         vhost_vq_init_access(vq);
1603                         mutex_unlock(&vq->mutex);
1604                 }
1605                 ret = 0;
1606         } else {
1607                 ret = -EEXIST;
1608         }
1609
1610         /*
1611          * Act as synchronize_rcu to make sure access to
1612          * old vs->vs_tpg is finished.
1613          */
1614         vhost_scsi_flush(vs);
1615         kfree(vs->vs_tpg);
1616         vs->vs_tpg = vs_tpg;
1617         goto out;
1618
1619 destroy_vq_cmds:
1620         for (i--; i >= VHOST_SCSI_VQ_IO; i--) {
1621                 if (!vhost_vq_get_backend(&vs->vqs[i].vq))
1622                         vhost_scsi_destroy_vq_cmds(&vs->vqs[i].vq);
1623         }
1624 undepend:
1625         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1626                 tpg = vs_tpg[i];
1627                 if (tpg) {
1628                         mutex_lock(&tpg->tv_tpg_mutex);
1629                         tpg->vhost_scsi = NULL;
1630                         tpg->tv_tpg_vhost_count--;
1631                         mutex_unlock(&tpg->tv_tpg_mutex);
1632                         target_undepend_item(&tpg->se_tpg.tpg_group.cg_item);
1633                 }
1634         }
1635         kfree(vs_tpg);
1636 out:
1637         mutex_unlock(&vs->dev.mutex);
1638         return ret;
1639 }
1640
1641 static int
1642 vhost_scsi_clear_endpoint(struct vhost_scsi *vs,
1643                           struct vhost_scsi_target *t)
1644 {
1645         struct se_portal_group *se_tpg;
1646         struct vhost_scsi_tport *tv_tport;
1647         struct vhost_scsi_tpg *tpg;
1648         struct vhost_virtqueue *vq;
1649         bool match = false;
1650         int index, ret, i;
1651         u8 target;
1652
1653         mutex_lock(&vs->dev.mutex);
1654         /* Verify that ring has been setup correctly. */
1655         for (index = 0; index < vs->dev.nvqs; ++index) {
1656                 if (!vhost_vq_access_ok(&vs->vqs[index].vq)) {
1657                         ret = -EFAULT;
1658                         goto err_dev;
1659                 }
1660         }
1661
1662         if (!vs->vs_tpg) {
1663                 ret = 0;
1664                 goto err_dev;
1665         }
1666
1667         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1668                 target = i;
1669                 tpg = vs->vs_tpg[target];
1670                 if (!tpg)
1671                         continue;
1672
1673                 tv_tport = tpg->tport;
1674                 if (!tv_tport) {
1675                         ret = -ENODEV;
1676                         goto err_dev;
1677                 }
1678
1679                 if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
1680                         pr_warn("tv_tport->tport_name: %s, tpg->tport_tpgt: %hu"
1681                                 " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
1682                                 tv_tport->tport_name, tpg->tport_tpgt,
1683                                 t->vhost_wwpn, t->vhost_tpgt);
1684                         ret = -EINVAL;
1685                         goto err_dev;
1686                 }
1687                 match = true;
1688         }
1689         if (!match)
1690                 goto free_vs_tpg;
1691
1692         /* Prevent new cmds from starting and accessing the tpgs/sessions */
1693         for (i = 0; i < vs->dev.nvqs; i++) {
1694                 vq = &vs->vqs[i].vq;
1695                 mutex_lock(&vq->mutex);
1696                 vhost_vq_set_backend(vq, NULL);
1697                 mutex_unlock(&vq->mutex);
1698         }
1699         /* Make sure cmds are not running before tearing them down. */
1700         vhost_scsi_flush(vs);
1701
1702         for (i = 0; i < vs->dev.nvqs; i++) {
1703                 vq = &vs->vqs[i].vq;
1704                 vhost_scsi_destroy_vq_cmds(vq);
1705         }
1706
1707         /*
1708          * We can now release our hold on the tpg and sessions and userspace
1709          * can free them after this point.
1710          */
1711         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
1712                 target = i;
1713                 tpg = vs->vs_tpg[target];
1714                 if (!tpg)
1715                         continue;
1716
1717                 mutex_lock(&tpg->tv_tpg_mutex);
1718
1719                 tpg->tv_tpg_vhost_count--;
1720                 tpg->vhost_scsi = NULL;
1721                 vs->vs_tpg[target] = NULL;
1722
1723                 mutex_unlock(&tpg->tv_tpg_mutex);
1724
1725                 se_tpg = &tpg->se_tpg;
1726                 target_undepend_item(&se_tpg->tpg_group.cg_item);
1727         }
1728
1729 free_vs_tpg:
1730         /*
1731          * Act as synchronize_rcu to make sure access to
1732          * old vs->vs_tpg is finished.
1733          */
1734         vhost_scsi_flush(vs);
1735         kfree(vs->vs_tpg);
1736         vs->vs_tpg = NULL;
1737         WARN_ON(vs->vs_events_nr);
1738         mutex_unlock(&vs->dev.mutex);
1739         return 0;
1740
1741 err_dev:
1742         mutex_unlock(&vs->dev.mutex);
1743         return ret;
1744 }
1745
1746 static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features)
1747 {
1748         struct vhost_virtqueue *vq;
1749         int i;
1750
1751         if (features & ~VHOST_SCSI_FEATURES)
1752                 return -EOPNOTSUPP;
1753
1754         mutex_lock(&vs->dev.mutex);
1755         if ((features & (1 << VHOST_F_LOG_ALL)) &&
1756             !vhost_log_access_ok(&vs->dev)) {
1757                 mutex_unlock(&vs->dev.mutex);
1758                 return -EFAULT;
1759         }
1760
1761         for (i = 0; i < vs->dev.nvqs; i++) {
1762                 vq = &vs->vqs[i].vq;
1763                 mutex_lock(&vq->mutex);
1764                 vq->acked_features = features;
1765                 mutex_unlock(&vq->mutex);
1766         }
1767         mutex_unlock(&vs->dev.mutex);
1768         return 0;
1769 }
1770
1771 static int vhost_scsi_open(struct inode *inode, struct file *f)
1772 {
1773         struct vhost_scsi *vs;
1774         struct vhost_virtqueue **vqs;
1775         int r = -ENOMEM, i, nvqs = vhost_scsi_max_io_vqs;
1776
1777         vs = kvzalloc(sizeof(*vs), GFP_KERNEL);
1778         if (!vs)
1779                 goto err_vs;
1780
1781         if (nvqs > VHOST_SCSI_MAX_IO_VQ) {
1782                 pr_err("Invalid max_io_vqs of %d. Using %d.\n", nvqs,
1783                        VHOST_SCSI_MAX_IO_VQ);
1784                 nvqs = VHOST_SCSI_MAX_IO_VQ;
1785         } else if (nvqs == 0) {
1786                 pr_err("Invalid max_io_vqs of %d. Using 1.\n", nvqs);
1787                 nvqs = 1;
1788         }
1789         nvqs += VHOST_SCSI_VQ_IO;
1790
1791         vs->compl_bitmap = bitmap_alloc(nvqs, GFP_KERNEL);
1792         if (!vs->compl_bitmap)
1793                 goto err_compl_bitmap;
1794
1795         vs->old_inflight = kmalloc_array(nvqs, sizeof(*vs->old_inflight),
1796                                          GFP_KERNEL | __GFP_ZERO);
1797         if (!vs->old_inflight)
1798                 goto err_inflight;
1799
1800         vs->vqs = kmalloc_array(nvqs, sizeof(*vs->vqs),
1801                                 GFP_KERNEL | __GFP_ZERO);
1802         if (!vs->vqs)
1803                 goto err_vqs;
1804
1805         vqs = kmalloc_array(nvqs, sizeof(*vqs), GFP_KERNEL);
1806         if (!vqs)
1807                 goto err_local_vqs;
1808
1809         vhost_work_init(&vs->vs_completion_work, vhost_scsi_complete_cmd_work);
1810         vhost_work_init(&vs->vs_event_work, vhost_scsi_evt_work);
1811
1812         vs->vs_events_nr = 0;
1813         vs->vs_events_missed = false;
1814
1815         vqs[VHOST_SCSI_VQ_CTL] = &vs->vqs[VHOST_SCSI_VQ_CTL].vq;
1816         vqs[VHOST_SCSI_VQ_EVT] = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1817         vs->vqs[VHOST_SCSI_VQ_CTL].vq.handle_kick = vhost_scsi_ctl_handle_kick;
1818         vs->vqs[VHOST_SCSI_VQ_EVT].vq.handle_kick = vhost_scsi_evt_handle_kick;
1819         for (i = VHOST_SCSI_VQ_IO; i < nvqs; i++) {
1820                 vqs[i] = &vs->vqs[i].vq;
1821                 vs->vqs[i].vq.handle_kick = vhost_scsi_handle_kick;
1822         }
1823         vhost_dev_init(&vs->dev, vqs, nvqs, UIO_MAXIOV,
1824                        VHOST_SCSI_WEIGHT, 0, true, NULL);
1825
1826         vhost_scsi_init_inflight(vs, NULL);
1827
1828         f->private_data = vs;
1829         return 0;
1830
1831 err_local_vqs:
1832         kfree(vs->vqs);
1833 err_vqs:
1834         kfree(vs->old_inflight);
1835 err_inflight:
1836         bitmap_free(vs->compl_bitmap);
1837 err_compl_bitmap:
1838         kvfree(vs);
1839 err_vs:
1840         return r;
1841 }
1842
1843 static int vhost_scsi_release(struct inode *inode, struct file *f)
1844 {
1845         struct vhost_scsi *vs = f->private_data;
1846         struct vhost_scsi_target t;
1847
1848         mutex_lock(&vs->dev.mutex);
1849         memcpy(t.vhost_wwpn, vs->vs_vhost_wwpn, sizeof(t.vhost_wwpn));
1850         mutex_unlock(&vs->dev.mutex);
1851         vhost_scsi_clear_endpoint(vs, &t);
1852         vhost_dev_stop(&vs->dev);
1853         vhost_dev_cleanup(&vs->dev);
1854         kfree(vs->dev.vqs);
1855         kfree(vs->vqs);
1856         kfree(vs->old_inflight);
1857         bitmap_free(vs->compl_bitmap);
1858         kvfree(vs);
1859         return 0;
1860 }
1861
1862 static long
1863 vhost_scsi_ioctl(struct file *f,
1864                  unsigned int ioctl,
1865                  unsigned long arg)
1866 {
1867         struct vhost_scsi *vs = f->private_data;
1868         struct vhost_scsi_target backend;
1869         void __user *argp = (void __user *)arg;
1870         u64 __user *featurep = argp;
1871         u32 __user *eventsp = argp;
1872         u32 events_missed;
1873         u64 features;
1874         int r, abi_version = VHOST_SCSI_ABI_VERSION;
1875         struct vhost_virtqueue *vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1876
1877         switch (ioctl) {
1878         case VHOST_SCSI_SET_ENDPOINT:
1879                 if (copy_from_user(&backend, argp, sizeof backend))
1880                         return -EFAULT;
1881                 if (backend.reserved != 0)
1882                         return -EOPNOTSUPP;
1883
1884                 return vhost_scsi_set_endpoint(vs, &backend);
1885         case VHOST_SCSI_CLEAR_ENDPOINT:
1886                 if (copy_from_user(&backend, argp, sizeof backend))
1887                         return -EFAULT;
1888                 if (backend.reserved != 0)
1889                         return -EOPNOTSUPP;
1890
1891                 return vhost_scsi_clear_endpoint(vs, &backend);
1892         case VHOST_SCSI_GET_ABI_VERSION:
1893                 if (copy_to_user(argp, &abi_version, sizeof abi_version))
1894                         return -EFAULT;
1895                 return 0;
1896         case VHOST_SCSI_SET_EVENTS_MISSED:
1897                 if (get_user(events_missed, eventsp))
1898                         return -EFAULT;
1899                 mutex_lock(&vq->mutex);
1900                 vs->vs_events_missed = events_missed;
1901                 mutex_unlock(&vq->mutex);
1902                 return 0;
1903         case VHOST_SCSI_GET_EVENTS_MISSED:
1904                 mutex_lock(&vq->mutex);
1905                 events_missed = vs->vs_events_missed;
1906                 mutex_unlock(&vq->mutex);
1907                 if (put_user(events_missed, eventsp))
1908                         return -EFAULT;
1909                 return 0;
1910         case VHOST_GET_FEATURES:
1911                 features = VHOST_SCSI_FEATURES;
1912                 if (copy_to_user(featurep, &features, sizeof features))
1913                         return -EFAULT;
1914                 return 0;
1915         case VHOST_SET_FEATURES:
1916                 if (copy_from_user(&features, featurep, sizeof features))
1917                         return -EFAULT;
1918                 return vhost_scsi_set_features(vs, features);
1919         default:
1920                 mutex_lock(&vs->dev.mutex);
1921                 r = vhost_dev_ioctl(&vs->dev, ioctl, argp);
1922                 /* TODO: flush backend after dev ioctl. */
1923                 if (r == -ENOIOCTLCMD)
1924                         r = vhost_vring_ioctl(&vs->dev, ioctl, argp);
1925                 mutex_unlock(&vs->dev.mutex);
1926                 return r;
1927         }
1928 }
1929
1930 static const struct file_operations vhost_scsi_fops = {
1931         .owner          = THIS_MODULE,
1932         .release        = vhost_scsi_release,
1933         .unlocked_ioctl = vhost_scsi_ioctl,
1934         .compat_ioctl   = compat_ptr_ioctl,
1935         .open           = vhost_scsi_open,
1936         .llseek         = noop_llseek,
1937 };
1938
1939 static struct miscdevice vhost_scsi_misc = {
1940         MISC_DYNAMIC_MINOR,
1941         "vhost-scsi",
1942         &vhost_scsi_fops,
1943 };
1944
1945 static int __init vhost_scsi_register(void)
1946 {
1947         return misc_register(&vhost_scsi_misc);
1948 }
1949
1950 static void vhost_scsi_deregister(void)
1951 {
1952         misc_deregister(&vhost_scsi_misc);
1953 }
1954
1955 static char *vhost_scsi_dump_proto_id(struct vhost_scsi_tport *tport)
1956 {
1957         switch (tport->tport_proto_id) {
1958         case SCSI_PROTOCOL_SAS:
1959                 return "SAS";
1960         case SCSI_PROTOCOL_FCP:
1961                 return "FCP";
1962         case SCSI_PROTOCOL_ISCSI:
1963                 return "iSCSI";
1964         default:
1965                 break;
1966         }
1967
1968         return "Unknown";
1969 }
1970
1971 static void
1972 vhost_scsi_do_plug(struct vhost_scsi_tpg *tpg,
1973                   struct se_lun *lun, bool plug)
1974 {
1975
1976         struct vhost_scsi *vs = tpg->vhost_scsi;
1977         struct vhost_virtqueue *vq;
1978         u32 reason;
1979
1980         if (!vs)
1981                 return;
1982
1983         if (plug)
1984                 reason = VIRTIO_SCSI_EVT_RESET_RESCAN;
1985         else
1986                 reason = VIRTIO_SCSI_EVT_RESET_REMOVED;
1987
1988         vq = &vs->vqs[VHOST_SCSI_VQ_EVT].vq;
1989         mutex_lock(&vq->mutex);
1990         /*
1991          * We can't queue events if the backend has been cleared, because
1992          * we could end up queueing an event after the flush.
1993          */
1994         if (!vhost_vq_get_backend(vq))
1995                 goto unlock;
1996
1997         if (vhost_has_feature(vq, VIRTIO_SCSI_F_HOTPLUG))
1998                 vhost_scsi_send_evt(vs, tpg, lun,
1999                                    VIRTIO_SCSI_T_TRANSPORT_RESET, reason);
2000 unlock:
2001         mutex_unlock(&vq->mutex);
2002 }
2003
2004 static void vhost_scsi_hotplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
2005 {
2006         vhost_scsi_do_plug(tpg, lun, true);
2007 }
2008
2009 static void vhost_scsi_hotunplug(struct vhost_scsi_tpg *tpg, struct se_lun *lun)
2010 {
2011         vhost_scsi_do_plug(tpg, lun, false);
2012 }
2013
2014 static int vhost_scsi_port_link(struct se_portal_group *se_tpg,
2015                                struct se_lun *lun)
2016 {
2017         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2018                                 struct vhost_scsi_tpg, se_tpg);
2019
2020         mutex_lock(&tpg->tv_tpg_mutex);
2021         tpg->tv_tpg_port_count++;
2022         vhost_scsi_hotplug(tpg, lun);
2023         mutex_unlock(&tpg->tv_tpg_mutex);
2024
2025         return 0;
2026 }
2027
2028 static void vhost_scsi_port_unlink(struct se_portal_group *se_tpg,
2029                                   struct se_lun *lun)
2030 {
2031         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2032                                 struct vhost_scsi_tpg, se_tpg);
2033
2034         mutex_lock(&tpg->tv_tpg_mutex);
2035         tpg->tv_tpg_port_count--;
2036         vhost_scsi_hotunplug(tpg, lun);
2037         mutex_unlock(&tpg->tv_tpg_mutex);
2038 }
2039
2040 static ssize_t vhost_scsi_tpg_attrib_fabric_prot_type_store(
2041                 struct config_item *item, const char *page, size_t count)
2042 {
2043         struct se_portal_group *se_tpg = attrib_to_tpg(item);
2044         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2045                                 struct vhost_scsi_tpg, se_tpg);
2046         unsigned long val;
2047         int ret = kstrtoul(page, 0, &val);
2048
2049         if (ret) {
2050                 pr_err("kstrtoul() returned %d for fabric_prot_type\n", ret);
2051                 return ret;
2052         }
2053         if (val != 0 && val != 1 && val != 3) {
2054                 pr_err("Invalid vhost_scsi fabric_prot_type: %lu\n", val);
2055                 return -EINVAL;
2056         }
2057         tpg->tv_fabric_prot_type = val;
2058
2059         return count;
2060 }
2061
2062 static ssize_t vhost_scsi_tpg_attrib_fabric_prot_type_show(
2063                 struct config_item *item, char *page)
2064 {
2065         struct se_portal_group *se_tpg = attrib_to_tpg(item);
2066         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2067                                 struct vhost_scsi_tpg, se_tpg);
2068
2069         return sysfs_emit(page, "%d\n", tpg->tv_fabric_prot_type);
2070 }
2071
2072 CONFIGFS_ATTR(vhost_scsi_tpg_attrib_, fabric_prot_type);
2073
2074 static struct configfs_attribute *vhost_scsi_tpg_attrib_attrs[] = {
2075         &vhost_scsi_tpg_attrib_attr_fabric_prot_type,
2076         NULL,
2077 };
2078
2079 static int vhost_scsi_make_nexus(struct vhost_scsi_tpg *tpg,
2080                                 const char *name)
2081 {
2082         struct vhost_scsi_nexus *tv_nexus;
2083
2084         mutex_lock(&tpg->tv_tpg_mutex);
2085         if (tpg->tpg_nexus) {
2086                 mutex_unlock(&tpg->tv_tpg_mutex);
2087                 pr_debug("tpg->tpg_nexus already exists\n");
2088                 return -EEXIST;
2089         }
2090
2091         tv_nexus = kzalloc(sizeof(*tv_nexus), GFP_KERNEL);
2092         if (!tv_nexus) {
2093                 mutex_unlock(&tpg->tv_tpg_mutex);
2094                 pr_err("Unable to allocate struct vhost_scsi_nexus\n");
2095                 return -ENOMEM;
2096         }
2097         /*
2098          * Since we are running in 'demo mode' this call with generate a
2099          * struct se_node_acl for the vhost_scsi struct se_portal_group with
2100          * the SCSI Initiator port name of the passed configfs group 'name'.
2101          */
2102         tv_nexus->tvn_se_sess = target_setup_session(&tpg->se_tpg, 0, 0,
2103                                         TARGET_PROT_DIN_PASS | TARGET_PROT_DOUT_PASS,
2104                                         (unsigned char *)name, tv_nexus, NULL);
2105         if (IS_ERR(tv_nexus->tvn_se_sess)) {
2106                 mutex_unlock(&tpg->tv_tpg_mutex);
2107                 kfree(tv_nexus);
2108                 return -ENOMEM;
2109         }
2110         tpg->tpg_nexus = tv_nexus;
2111
2112         mutex_unlock(&tpg->tv_tpg_mutex);
2113         return 0;
2114 }
2115
2116 static int vhost_scsi_drop_nexus(struct vhost_scsi_tpg *tpg)
2117 {
2118         struct se_session *se_sess;
2119         struct vhost_scsi_nexus *tv_nexus;
2120
2121         mutex_lock(&tpg->tv_tpg_mutex);
2122         tv_nexus = tpg->tpg_nexus;
2123         if (!tv_nexus) {
2124                 mutex_unlock(&tpg->tv_tpg_mutex);
2125                 return -ENODEV;
2126         }
2127
2128         se_sess = tv_nexus->tvn_se_sess;
2129         if (!se_sess) {
2130                 mutex_unlock(&tpg->tv_tpg_mutex);
2131                 return -ENODEV;
2132         }
2133
2134         if (tpg->tv_tpg_port_count != 0) {
2135                 mutex_unlock(&tpg->tv_tpg_mutex);
2136                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
2137                         " active TPG port count: %d\n",
2138                         tpg->tv_tpg_port_count);
2139                 return -EBUSY;
2140         }
2141
2142         if (tpg->tv_tpg_vhost_count != 0) {
2143                 mutex_unlock(&tpg->tv_tpg_mutex);
2144                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
2145                         " active TPG vhost count: %d\n",
2146                         tpg->tv_tpg_vhost_count);
2147                 return -EBUSY;
2148         }
2149
2150         pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated"
2151                 " %s Initiator Port: %s\n", vhost_scsi_dump_proto_id(tpg->tport),
2152                 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
2153
2154         /*
2155          * Release the SCSI I_T Nexus to the emulated vhost Target Port
2156          */
2157         target_remove_session(se_sess);
2158         tpg->tpg_nexus = NULL;
2159         mutex_unlock(&tpg->tv_tpg_mutex);
2160
2161         kfree(tv_nexus);
2162         return 0;
2163 }
2164
2165 static ssize_t vhost_scsi_tpg_nexus_show(struct config_item *item, char *page)
2166 {
2167         struct se_portal_group *se_tpg = to_tpg(item);
2168         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2169                                 struct vhost_scsi_tpg, se_tpg);
2170         struct vhost_scsi_nexus *tv_nexus;
2171         ssize_t ret;
2172
2173         mutex_lock(&tpg->tv_tpg_mutex);
2174         tv_nexus = tpg->tpg_nexus;
2175         if (!tv_nexus) {
2176                 mutex_unlock(&tpg->tv_tpg_mutex);
2177                 return -ENODEV;
2178         }
2179         ret = sysfs_emit(page, "%s\n",
2180                         tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
2181         mutex_unlock(&tpg->tv_tpg_mutex);
2182
2183         return ret;
2184 }
2185
2186 static ssize_t vhost_scsi_tpg_nexus_store(struct config_item *item,
2187                 const char *page, size_t count)
2188 {
2189         struct se_portal_group *se_tpg = to_tpg(item);
2190         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2191                                 struct vhost_scsi_tpg, se_tpg);
2192         struct vhost_scsi_tport *tport_wwn = tpg->tport;
2193         unsigned char i_port[VHOST_SCSI_NAMELEN], *ptr, *port_ptr;
2194         int ret;
2195         /*
2196          * Shutdown the active I_T nexus if 'NULL' is passed..
2197          */
2198         if (!strncmp(page, "NULL", 4)) {
2199                 ret = vhost_scsi_drop_nexus(tpg);
2200                 return (!ret) ? count : ret;
2201         }
2202         /*
2203          * Otherwise make sure the passed virtual Initiator port WWN matches
2204          * the fabric protocol_id set in vhost_scsi_make_tport(), and call
2205          * vhost_scsi_make_nexus().
2206          */
2207         if (strlen(page) >= VHOST_SCSI_NAMELEN) {
2208                 pr_err("Emulated NAA Sas Address: %s, exceeds"
2209                                 " max: %d\n", page, VHOST_SCSI_NAMELEN);
2210                 return -EINVAL;
2211         }
2212         snprintf(&i_port[0], VHOST_SCSI_NAMELEN, "%s", page);
2213
2214         ptr = strstr(i_port, "naa.");
2215         if (ptr) {
2216                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
2217                         pr_err("Passed SAS Initiator Port %s does not"
2218                                 " match target port protoid: %s\n", i_port,
2219                                 vhost_scsi_dump_proto_id(tport_wwn));
2220                         return -EINVAL;
2221                 }
2222                 port_ptr = &i_port[0];
2223                 goto check_newline;
2224         }
2225         ptr = strstr(i_port, "fc.");
2226         if (ptr) {
2227                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
2228                         pr_err("Passed FCP Initiator Port %s does not"
2229                                 " match target port protoid: %s\n", i_port,
2230                                 vhost_scsi_dump_proto_id(tport_wwn));
2231                         return -EINVAL;
2232                 }
2233                 port_ptr = &i_port[3]; /* Skip over "fc." */
2234                 goto check_newline;
2235         }
2236         ptr = strstr(i_port, "iqn.");
2237         if (ptr) {
2238                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
2239                         pr_err("Passed iSCSI Initiator Port %s does not"
2240                                 " match target port protoid: %s\n", i_port,
2241                                 vhost_scsi_dump_proto_id(tport_wwn));
2242                         return -EINVAL;
2243                 }
2244                 port_ptr = &i_port[0];
2245                 goto check_newline;
2246         }
2247         pr_err("Unable to locate prefix for emulated Initiator Port:"
2248                         " %s\n", i_port);
2249         return -EINVAL;
2250         /*
2251          * Clear any trailing newline for the NAA WWN
2252          */
2253 check_newline:
2254         if (i_port[strlen(i_port)-1] == '\n')
2255                 i_port[strlen(i_port)-1] = '\0';
2256
2257         ret = vhost_scsi_make_nexus(tpg, port_ptr);
2258         if (ret < 0)
2259                 return ret;
2260
2261         return count;
2262 }
2263
2264 CONFIGFS_ATTR(vhost_scsi_tpg_, nexus);
2265
2266 static struct configfs_attribute *vhost_scsi_tpg_attrs[] = {
2267         &vhost_scsi_tpg_attr_nexus,
2268         NULL,
2269 };
2270
2271 static struct se_portal_group *
2272 vhost_scsi_make_tpg(struct se_wwn *wwn, const char *name)
2273 {
2274         struct vhost_scsi_tport *tport = container_of(wwn,
2275                         struct vhost_scsi_tport, tport_wwn);
2276
2277         struct vhost_scsi_tpg *tpg;
2278         u16 tpgt;
2279         int ret;
2280
2281         if (strstr(name, "tpgt_") != name)
2282                 return ERR_PTR(-EINVAL);
2283         if (kstrtou16(name + 5, 10, &tpgt) || tpgt >= VHOST_SCSI_MAX_TARGET)
2284                 return ERR_PTR(-EINVAL);
2285
2286         tpg = kzalloc(sizeof(*tpg), GFP_KERNEL);
2287         if (!tpg) {
2288                 pr_err("Unable to allocate struct vhost_scsi_tpg");
2289                 return ERR_PTR(-ENOMEM);
2290         }
2291         mutex_init(&tpg->tv_tpg_mutex);
2292         INIT_LIST_HEAD(&tpg->tv_tpg_list);
2293         tpg->tport = tport;
2294         tpg->tport_tpgt = tpgt;
2295
2296         ret = core_tpg_register(wwn, &tpg->se_tpg, tport->tport_proto_id);
2297         if (ret < 0) {
2298                 kfree(tpg);
2299                 return NULL;
2300         }
2301         mutex_lock(&vhost_scsi_mutex);
2302         list_add_tail(&tpg->tv_tpg_list, &vhost_scsi_list);
2303         mutex_unlock(&vhost_scsi_mutex);
2304
2305         return &tpg->se_tpg;
2306 }
2307
2308 static void vhost_scsi_drop_tpg(struct se_portal_group *se_tpg)
2309 {
2310         struct vhost_scsi_tpg *tpg = container_of(se_tpg,
2311                                 struct vhost_scsi_tpg, se_tpg);
2312
2313         mutex_lock(&vhost_scsi_mutex);
2314         list_del(&tpg->tv_tpg_list);
2315         mutex_unlock(&vhost_scsi_mutex);
2316         /*
2317          * Release the virtual I_T Nexus for this vhost TPG
2318          */
2319         vhost_scsi_drop_nexus(tpg);
2320         /*
2321          * Deregister the se_tpg from TCM..
2322          */
2323         core_tpg_deregister(se_tpg);
2324         kfree(tpg);
2325 }
2326
2327 static struct se_wwn *
2328 vhost_scsi_make_tport(struct target_fabric_configfs *tf,
2329                      struct config_group *group,
2330                      const char *name)
2331 {
2332         struct vhost_scsi_tport *tport;
2333         char *ptr;
2334         u64 wwpn = 0;
2335         int off = 0;
2336
2337         /* if (vhost_scsi_parse_wwn(name, &wwpn, 1) < 0)
2338                 return ERR_PTR(-EINVAL); */
2339
2340         tport = kzalloc(sizeof(*tport), GFP_KERNEL);
2341         if (!tport) {
2342                 pr_err("Unable to allocate struct vhost_scsi_tport");
2343                 return ERR_PTR(-ENOMEM);
2344         }
2345         tport->tport_wwpn = wwpn;
2346         /*
2347          * Determine the emulated Protocol Identifier and Target Port Name
2348          * based on the incoming configfs directory name.
2349          */
2350         ptr = strstr(name, "naa.");
2351         if (ptr) {
2352                 tport->tport_proto_id = SCSI_PROTOCOL_SAS;
2353                 goto check_len;
2354         }
2355         ptr = strstr(name, "fc.");
2356         if (ptr) {
2357                 tport->tport_proto_id = SCSI_PROTOCOL_FCP;
2358                 off = 3; /* Skip over "fc." */
2359                 goto check_len;
2360         }
2361         ptr = strstr(name, "iqn.");
2362         if (ptr) {
2363                 tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
2364                 goto check_len;
2365         }
2366
2367         pr_err("Unable to locate prefix for emulated Target Port:"
2368                         " %s\n", name);
2369         kfree(tport);
2370         return ERR_PTR(-EINVAL);
2371
2372 check_len:
2373         if (strlen(name) >= VHOST_SCSI_NAMELEN) {
2374                 pr_err("Emulated %s Address: %s, exceeds"
2375                         " max: %d\n", name, vhost_scsi_dump_proto_id(tport),
2376                         VHOST_SCSI_NAMELEN);
2377                 kfree(tport);
2378                 return ERR_PTR(-EINVAL);
2379         }
2380         snprintf(&tport->tport_name[0], VHOST_SCSI_NAMELEN, "%s", &name[off]);
2381
2382         pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target"
2383                 " %s Address: %s\n", vhost_scsi_dump_proto_id(tport), name);
2384
2385         return &tport->tport_wwn;
2386 }
2387
2388 static void vhost_scsi_drop_tport(struct se_wwn *wwn)
2389 {
2390         struct vhost_scsi_tport *tport = container_of(wwn,
2391                                 struct vhost_scsi_tport, tport_wwn);
2392
2393         pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target"
2394                 " %s Address: %s\n", vhost_scsi_dump_proto_id(tport),
2395                 tport->tport_name);
2396
2397         kfree(tport);
2398 }
2399
2400 static ssize_t
2401 vhost_scsi_wwn_version_show(struct config_item *item, char *page)
2402 {
2403         return sysfs_emit(page, "TCM_VHOST fabric module %s on %s/%s"
2404                 "on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
2405                 utsname()->machine);
2406 }
2407
2408 CONFIGFS_ATTR_RO(vhost_scsi_wwn_, version);
2409
2410 static struct configfs_attribute *vhost_scsi_wwn_attrs[] = {
2411         &vhost_scsi_wwn_attr_version,
2412         NULL,
2413 };
2414
2415 static const struct target_core_fabric_ops vhost_scsi_ops = {
2416         .module                         = THIS_MODULE,
2417         .fabric_name                    = "vhost",
2418         .max_data_sg_nents              = VHOST_SCSI_PREALLOC_SGLS,
2419         .tpg_get_wwn                    = vhost_scsi_get_fabric_wwn,
2420         .tpg_get_tag                    = vhost_scsi_get_tpgt,
2421         .tpg_check_demo_mode            = vhost_scsi_check_true,
2422         .tpg_check_demo_mode_cache      = vhost_scsi_check_true,
2423         .tpg_check_prot_fabric_only     = vhost_scsi_check_prot_fabric_only,
2424         .release_cmd                    = vhost_scsi_release_cmd,
2425         .check_stop_free                = vhost_scsi_check_stop_free,
2426         .sess_get_initiator_sid         = NULL,
2427         .write_pending                  = vhost_scsi_write_pending,
2428         .queue_data_in                  = vhost_scsi_queue_data_in,
2429         .queue_status                   = vhost_scsi_queue_status,
2430         .queue_tm_rsp                   = vhost_scsi_queue_tm_rsp,
2431         .aborted_task                   = vhost_scsi_aborted_task,
2432         /*
2433          * Setup callers for generic logic in target_core_fabric_configfs.c
2434          */
2435         .fabric_make_wwn                = vhost_scsi_make_tport,
2436         .fabric_drop_wwn                = vhost_scsi_drop_tport,
2437         .fabric_make_tpg                = vhost_scsi_make_tpg,
2438         .fabric_drop_tpg                = vhost_scsi_drop_tpg,
2439         .fabric_post_link               = vhost_scsi_port_link,
2440         .fabric_pre_unlink              = vhost_scsi_port_unlink,
2441
2442         .tfc_wwn_attrs                  = vhost_scsi_wwn_attrs,
2443         .tfc_tpg_base_attrs             = vhost_scsi_tpg_attrs,
2444         .tfc_tpg_attrib_attrs           = vhost_scsi_tpg_attrib_attrs,
2445 };
2446
2447 static int __init vhost_scsi_init(void)
2448 {
2449         int ret = -ENOMEM;
2450
2451         pr_debug("TCM_VHOST fabric module %s on %s/%s"
2452                 " on "UTS_RELEASE"\n", VHOST_SCSI_VERSION, utsname()->sysname,
2453                 utsname()->machine);
2454
2455         ret = vhost_scsi_register();
2456         if (ret < 0)
2457                 goto out;
2458
2459         ret = target_register_template(&vhost_scsi_ops);
2460         if (ret < 0)
2461                 goto out_vhost_scsi_deregister;
2462
2463         return 0;
2464
2465 out_vhost_scsi_deregister:
2466         vhost_scsi_deregister();
2467 out:
2468         return ret;
2469 };
2470
2471 static void vhost_scsi_exit(void)
2472 {
2473         target_unregister_template(&vhost_scsi_ops);
2474         vhost_scsi_deregister();
2475 };
2476
2477 MODULE_DESCRIPTION("VHOST_SCSI series fabric driver");
2478 MODULE_ALIAS("tcm_vhost");
2479 MODULE_LICENSE("GPL");
2480 module_init(vhost_scsi_init);
2481 module_exit(vhost_scsi_exit);