Pileus Git - ~andy/linux/blob - drivers/vhost/tcm_vhost.c

   1 /*******************************************************************************
   2  * Vhost kernel TCM fabric driver for virtio SCSI initiators
   3  *
   4  * (C) Copyright 2010-2012 RisingTide Systems LLC.
   5  * (C) Copyright 2010-2012 IBM Corp.
   6  *
   7  * Licensed to the Linux Foundation under the General Public License (GPL) version 2.
   8  *
   9  * Authors: Nicholas A. Bellinger <nab@risingtidesystems.com>
  10  *          Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  ****************************************************************************/
  23
  24 #include <linux/module.h>
  25 #include <linux/moduleparam.h>
  26 #include <generated/utsrelease.h>
  27 #include <linux/utsname.h>
  28 #include <linux/init.h>
  29 #include <linux/slab.h>
  30 #include <linux/kthread.h>
  31 #include <linux/types.h>
  32 #include <linux/string.h>
  33 #include <linux/configfs.h>
  34 #include <linux/ctype.h>
  35 #include <linux/compat.h>
  36 #include <linux/eventfd.h>
  37 #include <linux/fs.h>
  38 #include <linux/miscdevice.h>
  39 #include <asm/unaligned.h>
  40 #include <scsi/scsi.h>
  41 #include <scsi/scsi_tcq.h>
  42 #include <target/target_core_base.h>
  43 #include <target/target_core_fabric.h>
  44 #include <target/target_core_fabric_configfs.h>
  45 #include <target/target_core_configfs.h>
  46 #include <target/configfs_macros.h>
  47 #include <linux/vhost.h>
  48 #include <linux/virtio_net.h> /* TODO vhost.h currently depends on this */
  49 #include <linux/virtio_scsi.h>
  50 #include <linux/llist.h>
  51 #include <linux/bitmap.h>
  52
  53 #include "vhost.c"
  54 #include "vhost.h"
  55 #include "tcm_vhost.h"
  56
  57 enum {
  58         VHOST_SCSI_VQ_CTL = 0,
  59         VHOST_SCSI_VQ_EVT = 1,
  60         VHOST_SCSI_VQ_IO = 2,
  61 };
  62
  63 /*
  64  * VIRTIO_RING_F_EVENT_IDX seems broken. Not sure the bug is in
  65  * kernel but disabling it helps.
  66  * TODO: debug and remove the workaround.
  67  */
  68 enum {
  69         VHOST_SCSI_FEATURES = VHOST_FEATURES & (~VIRTIO_RING_F_EVENT_IDX)
  70 };
  71
  72 #define VHOST_SCSI_MAX_TARGET   256
  73 #define VHOST_SCSI_MAX_VQ       128
  74
  75 struct vhost_scsi {
  76         /* Protected by vhost_scsi->dev.mutex */
  77         struct tcm_vhost_tpg **vs_tpg;
  78         char vs_vhost_wwpn[TRANSPORT_IQN_LEN];
  79
  80         struct vhost_dev dev;
  81         struct vhost_virtqueue vqs[VHOST_SCSI_MAX_VQ];
  82
  83         struct vhost_work vs_completion_work; /* cmd completion work item */
  84         struct llist_head vs_completion_list; /* cmd completion queue */
  85 };
  86
  87 /* Local pointer to allocated TCM configfs fabric module */
  88 static struct target_fabric_configfs *tcm_vhost_fabric_configfs;
  89
  90 static struct workqueue_struct *tcm_vhost_workqueue;
  91
  92 /* Global spinlock to protect tcm_vhost TPG list for vhost IOCTL access */
  93 static DEFINE_MUTEX(tcm_vhost_mutex);
  94 static LIST_HEAD(tcm_vhost_list);
  95
  96 static int iov_num_pages(struct iovec *iov)
  97 {
  98         return (PAGE_ALIGN((unsigned long)iov->iov_base + iov->iov_len) -
  99                ((unsigned long)iov->iov_base & PAGE_MASK)) >> PAGE_SHIFT;
 100 }
 101
 102 static int tcm_vhost_check_true(struct se_portal_group *se_tpg)
 103 {
 104         return 1;
 105 }
 106
 107 static int tcm_vhost_check_false(struct se_portal_group *se_tpg)
 108 {
 109         return 0;
 110 }
 111
 112 static char *tcm_vhost_get_fabric_name(void)
 113 {
 114         return "vhost";
 115 }
 116
 117 static u8 tcm_vhost_get_fabric_proto_ident(struct se_portal_group *se_tpg)
 118 {
 119         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 120                                 struct tcm_vhost_tpg, se_tpg);
 121         struct tcm_vhost_tport *tport = tpg->tport;
 122
 123         switch (tport->tport_proto_id) {
 124         case SCSI_PROTOCOL_SAS:
 125                 return sas_get_fabric_proto_ident(se_tpg);
 126         case SCSI_PROTOCOL_FCP:
 127                 return fc_get_fabric_proto_ident(se_tpg);
 128         case SCSI_PROTOCOL_ISCSI:
 129                 return iscsi_get_fabric_proto_ident(se_tpg);
 130         default:
 131                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 132                         " SAS emulation\n", tport->tport_proto_id);
 133                 break;
 134         }
 135
 136         return sas_get_fabric_proto_ident(se_tpg);
 137 }
 138
 139 static char *tcm_vhost_get_fabric_wwn(struct se_portal_group *se_tpg)
 140 {
 141         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 142                                 struct tcm_vhost_tpg, se_tpg);
 143         struct tcm_vhost_tport *tport = tpg->tport;
 144
 145         return &tport->tport_name[0];
 146 }
 147
 148 static u16 tcm_vhost_get_tag(struct se_portal_group *se_tpg)
 149 {
 150         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 151                                 struct tcm_vhost_tpg, se_tpg);
 152         return tpg->tport_tpgt;
 153 }
 154
 155 static u32 tcm_vhost_get_default_depth(struct se_portal_group *se_tpg)
 156 {
 157         return 1;
 158 }
 159
 160 static u32 tcm_vhost_get_pr_transport_id(struct se_portal_group *se_tpg,
 161         struct se_node_acl *se_nacl,
 162         struct t10_pr_registration *pr_reg,
 163         int *format_code,
 164         unsigned char *buf)
 165 {
 166         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 167                                 struct tcm_vhost_tpg, se_tpg);
 168         struct tcm_vhost_tport *tport = tpg->tport;
 169
 170         switch (tport->tport_proto_id) {
 171         case SCSI_PROTOCOL_SAS:
 172                 return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 173                                         format_code, buf);
 174         case SCSI_PROTOCOL_FCP:
 175                 return fc_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 176                                         format_code, buf);
 177         case SCSI_PROTOCOL_ISCSI:
 178                 return iscsi_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 179                                         format_code, buf);
 180         default:
 181                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 182                         " SAS emulation\n", tport->tport_proto_id);
 183                 break;
 184         }
 185
 186         return sas_get_pr_transport_id(se_tpg, se_nacl, pr_reg,
 187                         format_code, buf);
 188 }
 189
 190 static u32 tcm_vhost_get_pr_transport_id_len(struct se_portal_group *se_tpg,
 191         struct se_node_acl *se_nacl,
 192         struct t10_pr_registration *pr_reg,
 193         int *format_code)
 194 {
 195         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 196                                 struct tcm_vhost_tpg, se_tpg);
 197         struct tcm_vhost_tport *tport = tpg->tport;
 198
 199         switch (tport->tport_proto_id) {
 200         case SCSI_PROTOCOL_SAS:
 201                 return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 202                                         format_code);
 203         case SCSI_PROTOCOL_FCP:
 204                 return fc_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 205                                         format_code);
 206         case SCSI_PROTOCOL_ISCSI:
 207                 return iscsi_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 208                                         format_code);
 209         default:
 210                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 211                         " SAS emulation\n", tport->tport_proto_id);
 212                 break;
 213         }
 214
 215         return sas_get_pr_transport_id_len(se_tpg, se_nacl, pr_reg,
 216                         format_code);
 217 }
 218
 219 static char *tcm_vhost_parse_pr_out_transport_id(struct se_portal_group *se_tpg,
 220         const char *buf,
 221         u32 *out_tid_len,
 222         char **port_nexus_ptr)
 223 {
 224         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
 225                                 struct tcm_vhost_tpg, se_tpg);
 226         struct tcm_vhost_tport *tport = tpg->tport;
 227
 228         switch (tport->tport_proto_id) {
 229         case SCSI_PROTOCOL_SAS:
 230                 return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 231                                         port_nexus_ptr);
 232         case SCSI_PROTOCOL_FCP:
 233                 return fc_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 234                                         port_nexus_ptr);
 235         case SCSI_PROTOCOL_ISCSI:
 236                 return iscsi_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 237                                         port_nexus_ptr);
 238         default:
 239                 pr_err("Unknown tport_proto_id: 0x%02x, using"
 240                         " SAS emulation\n", tport->tport_proto_id);
 241                 break;
 242         }
 243
 244         return sas_parse_pr_out_transport_id(se_tpg, buf, out_tid_len,
 245                         port_nexus_ptr);
 246 }
 247
 248 static struct se_node_acl *tcm_vhost_alloc_fabric_acl(
 249         struct se_portal_group *se_tpg)
 250 {
 251         struct tcm_vhost_nacl *nacl;
 252
 253         nacl = kzalloc(sizeof(struct tcm_vhost_nacl), GFP_KERNEL);
 254         if (!nacl) {
 255                 pr_err("Unable to allocate struct tcm_vhost_nacl\n");
 256                 return NULL;
 257         }
 258
 259         return &nacl->se_node_acl;
 260 }
 261
 262 static void tcm_vhost_release_fabric_acl(struct se_portal_group *se_tpg,
 263         struct se_node_acl *se_nacl)
 264 {
 265         struct tcm_vhost_nacl *nacl = container_of(se_nacl,
 266                         struct tcm_vhost_nacl, se_node_acl);
 267         kfree(nacl);
 268 }
 269
 270 static u32 tcm_vhost_tpg_get_inst_index(struct se_portal_group *se_tpg)
 271 {
 272         return 1;
 273 }
 274
 275 static void tcm_vhost_release_cmd(struct se_cmd *se_cmd)
 276 {
 277         return;
 278 }
 279
 280 static int tcm_vhost_shutdown_session(struct se_session *se_sess)
 281 {
 282         return 0;
 283 }
 284
 285 static void tcm_vhost_close_session(struct se_session *se_sess)
 286 {
 287         return;
 288 }
 289
 290 static u32 tcm_vhost_sess_get_index(struct se_session *se_sess)
 291 {
 292         return 0;
 293 }
 294
 295 static int tcm_vhost_write_pending(struct se_cmd *se_cmd)
 296 {
 297         /* Go ahead and process the write immediately */
 298         target_execute_cmd(se_cmd);
 299         return 0;
 300 }
 301
 302 static int tcm_vhost_write_pending_status(struct se_cmd *se_cmd)
 303 {
 304         return 0;
 305 }
 306
 307 static void tcm_vhost_set_default_node_attrs(struct se_node_acl *nacl)
 308 {
 309         return;
 310 }
 311
 312 static u32 tcm_vhost_get_task_tag(struct se_cmd *se_cmd)
 313 {
 314         return 0;
 315 }
 316
 317 static int tcm_vhost_get_cmd_state(struct se_cmd *se_cmd)
 318 {
 319         return 0;
 320 }
 321
 322 static void vhost_scsi_complete_cmd(struct tcm_vhost_cmd *tv_cmd)
 323 {
 324         struct vhost_scsi *vs = tv_cmd->tvc_vhost;
 325
 326         llist_add(&tv_cmd->tvc_completion_list, &vs->vs_completion_list);
 327
 328         vhost_work_queue(&vs->dev, &vs->vs_completion_work);
 329 }
 330
 331 static int tcm_vhost_queue_data_in(struct se_cmd *se_cmd)
 332 {
 333         struct tcm_vhost_cmd *tv_cmd = container_of(se_cmd,
 334                                 struct tcm_vhost_cmd, tvc_se_cmd);
 335         vhost_scsi_complete_cmd(tv_cmd);
 336         return 0;
 337 }
 338
 339 static int tcm_vhost_queue_status(struct se_cmd *se_cmd)
 340 {
 341         struct tcm_vhost_cmd *tv_cmd = container_of(se_cmd,
 342                                 struct tcm_vhost_cmd, tvc_se_cmd);
 343         vhost_scsi_complete_cmd(tv_cmd);
 344         return 0;
 345 }
 346
 347 static int tcm_vhost_queue_tm_rsp(struct se_cmd *se_cmd)
 348 {
 349         return 0;
 350 }
 351
 352 static void vhost_scsi_free_cmd(struct tcm_vhost_cmd *tv_cmd)
 353 {
 354         struct se_cmd *se_cmd = &tv_cmd->tvc_se_cmd;
 355
 356         /* TODO locking against target/backend threads? */
 357         transport_generic_free_cmd(se_cmd, 1);
 358
 359         if (tv_cmd->tvc_sgl_count) {
 360                 u32 i;
 361                 for (i = 0; i < tv_cmd->tvc_sgl_count; i++)
 362                         put_page(sg_page(&tv_cmd->tvc_sgl[i]));
 363
 364                 kfree(tv_cmd->tvc_sgl);
 365         }
 366
 367         kfree(tv_cmd);
 368 }
 369
 370 /* Fill in status and signal that we are done processing this command
 371  *
 372  * This is scheduled in the vhost work queue so we are called with the owner
 373  * process mm and can access the vring.
 374  */
 375 static void vhost_scsi_complete_cmd_work(struct vhost_work *work)
 376 {
 377         struct vhost_scsi *vs = container_of(work, struct vhost_scsi,
 378                                         vs_completion_work);
 379         DECLARE_BITMAP(signal, VHOST_SCSI_MAX_VQ);
 380         struct virtio_scsi_cmd_resp v_rsp;
 381         struct tcm_vhost_cmd *tv_cmd;
 382         struct llist_node *llnode;
 383         struct se_cmd *se_cmd;
 384         int ret, vq;
 385
 386         bitmap_zero(signal, VHOST_SCSI_MAX_VQ);
 387         llnode = llist_del_all(&vs->vs_completion_list);
 388         while (llnode) {
 389                 tv_cmd = llist_entry(llnode, struct tcm_vhost_cmd,
 390                                      tvc_completion_list);
 391                 llnode = llist_next(llnode);
 392                 se_cmd = &tv_cmd->tvc_se_cmd;
 393
 394                 pr_debug("%s tv_cmd %p resid %u status %#02x\n", __func__,
 395                         tv_cmd, se_cmd->residual_count, se_cmd->scsi_status);
 396
 397                 memset(&v_rsp, 0, sizeof(v_rsp));
 398                 v_rsp.resid = se_cmd->residual_count;
 399                 /* TODO is status_qualifier field needed? */
 400                 v_rsp.status = se_cmd->scsi_status;
 401                 v_rsp.sense_len = se_cmd->scsi_sense_length;
 402                 memcpy(v_rsp.sense, tv_cmd->tvc_sense_buf,
 403                        v_rsp.sense_len);
 404                 ret = copy_to_user(tv_cmd->tvc_resp, &v_rsp, sizeof(v_rsp));
 405                 if (likely(ret == 0)) {
 406                         vhost_add_used(tv_cmd->tvc_vq, tv_cmd->tvc_vq_desc, 0);
 407                         vq = tv_cmd->tvc_vq - vs->vqs;
 408                         __set_bit(vq, signal);
 409                 } else
 410                         pr_err("Faulted on virtio_scsi_cmd_resp\n");
 411
 412                 vhost_scsi_free_cmd(tv_cmd);
 413         }
 414
 415         vq = -1;
 416         while ((vq = find_next_bit(signal, VHOST_SCSI_MAX_VQ, vq + 1))
 417                 < VHOST_SCSI_MAX_VQ)
 418                 vhost_signal(&vs->dev, &vs->vqs[vq]);
 419 }
 420
 421 static struct tcm_vhost_cmd *vhost_scsi_allocate_cmd(
 422         struct tcm_vhost_tpg *tv_tpg,
 423         struct virtio_scsi_cmd_req *v_req,
 424         u32 exp_data_len,
 425         int data_direction)
 426 {
 427         struct tcm_vhost_cmd *tv_cmd;
 428         struct tcm_vhost_nexus *tv_nexus;
 429
 430         tv_nexus = tv_tpg->tpg_nexus;
 431         if (!tv_nexus) {
 432                 pr_err("Unable to locate active struct tcm_vhost_nexus\n");
 433                 return ERR_PTR(-EIO);
 434         }
 435
 436         tv_cmd = kzalloc(sizeof(struct tcm_vhost_cmd), GFP_ATOMIC);
 437         if (!tv_cmd) {
 438                 pr_err("Unable to allocate struct tcm_vhost_cmd\n");
 439                 return ERR_PTR(-ENOMEM);
 440         }
 441         tv_cmd->tvc_tag = v_req->tag;
 442         tv_cmd->tvc_task_attr = v_req->task_attr;
 443         tv_cmd->tvc_exp_data_len = exp_data_len;
 444         tv_cmd->tvc_data_direction = data_direction;
 445         tv_cmd->tvc_nexus = tv_nexus;
 446
 447         return tv_cmd;
 448 }
 449
 450 /*
 451  * Map a user memory range into a scatterlist
 452  *
 453  * Returns the number of scatterlist entries used or -errno on error.
 454  */
 455 static int vhost_scsi_map_to_sgl(struct scatterlist *sgl,
 456         unsigned int sgl_count, struct iovec *iov, int write)
 457 {
 458         unsigned int npages = 0, pages_nr, offset, nbytes;
 459         struct scatterlist *sg = sgl;
 460         void __user *ptr = iov->iov_base;
 461         size_t len = iov->iov_len;
 462         struct page **pages;
 463         int ret, i;
 464
 465         pages_nr = iov_num_pages(iov);
 466         if (pages_nr > sgl_count)
 467                 return -ENOBUFS;
 468
 469         pages = kmalloc(pages_nr * sizeof(struct page *), GFP_KERNEL);
 470         if (!pages)
 471                 return -ENOMEM;
 472
 473         ret = get_user_pages_fast((unsigned long)ptr, pages_nr, write, pages);
 474         /* No pages were pinned */
 475         if (ret < 0)
 476                 goto out;
 477         /* Less pages pinned than wanted */
 478         if (ret != pages_nr) {
 479                 for (i = 0; i < ret; i++)
 480                         put_page(pages[i]);
 481                 ret = -EFAULT;
 482                 goto out;
 483         }
 484
 485         while (len > 0) {
 486                 offset = (uintptr_t)ptr & ~PAGE_MASK;
 487                 nbytes = min_t(unsigned int, PAGE_SIZE - offset, len);
 488                 sg_set_page(sg, pages[npages], nbytes, offset);
 489                 ptr += nbytes;
 490                 len -= nbytes;
 491                 sg++;
 492                 npages++;
 493         }
 494
 495 out:
 496         kfree(pages);
 497         return ret;
 498 }
 499
 500 static int vhost_scsi_map_iov_to_sgl(struct tcm_vhost_cmd *tv_cmd,
 501         struct iovec *iov, unsigned int niov, int write)
 502 {
 503         int ret;
 504         unsigned int i;
 505         u32 sgl_count;
 506         struct scatterlist *sg;
 507
 508         /*
 509          * Find out how long sglist needs to be
 510          */
 511         sgl_count = 0;
 512         for (i = 0; i < niov; i++)
 513                 sgl_count += iov_num_pages(&iov[i]);
 514
 515         /* TODO overflow checking */
 516
 517         sg = kmalloc(sizeof(tv_cmd->tvc_sgl[0]) * sgl_count, GFP_ATOMIC);
 518         if (!sg)
 519                 return -ENOMEM;
 520         pr_debug("%s sg %p sgl_count %u is_err %d\n", __func__,
 521                sg, sgl_count, !sg);
 522         sg_init_table(sg, sgl_count);
 523
 524         tv_cmd->tvc_sgl = sg;
 525         tv_cmd->tvc_sgl_count = sgl_count;
 526
 527         pr_debug("Mapping %u iovecs for %u pages\n", niov, sgl_count);
 528         for (i = 0; i < niov; i++) {
 529                 ret = vhost_scsi_map_to_sgl(sg, sgl_count, &iov[i], write);
 530                 if (ret < 0) {
 531                         for (i = 0; i < tv_cmd->tvc_sgl_count; i++)
 532                                 put_page(sg_page(&tv_cmd->tvc_sgl[i]));
 533                         kfree(tv_cmd->tvc_sgl);
 534                         tv_cmd->tvc_sgl = NULL;
 535                         tv_cmd->tvc_sgl_count = 0;
 536                         return ret;
 537                 }
 538
 539                 sg += ret;
 540                 sgl_count -= ret;
 541         }
 542         return 0;
 543 }
 544
 545 static void tcm_vhost_submission_work(struct work_struct *work)
 546 {
 547         struct tcm_vhost_cmd *tv_cmd =
 548                 container_of(work, struct tcm_vhost_cmd, work);
 549         struct tcm_vhost_nexus *tv_nexus;
 550         struct se_cmd *se_cmd = &tv_cmd->tvc_se_cmd;
 551         struct scatterlist *sg_ptr, *sg_bidi_ptr = NULL;
 552         int rc, sg_no_bidi = 0;
 553
 554         if (tv_cmd->tvc_sgl_count) {
 555                 sg_ptr = tv_cmd->tvc_sgl;
 556 /* FIXME: Fix BIDI operation in tcm_vhost_submission_work() */
 557 #if 0
 558                 if (se_cmd->se_cmd_flags & SCF_BIDI) {
 559                         sg_bidi_ptr = NULL;
 560                         sg_no_bidi = 0;
 561                 }
 562 #endif
 563         } else {
 564                 sg_ptr = NULL;
 565         }
 566         tv_nexus = tv_cmd->tvc_nexus;
 567
 568         rc = target_submit_cmd_map_sgls(se_cmd, tv_nexus->tvn_se_sess,
 569                         tv_cmd->tvc_cdb, &tv_cmd->tvc_sense_buf[0],
 570                         tv_cmd->tvc_lun, tv_cmd->tvc_exp_data_len,
 571                         tv_cmd->tvc_task_attr, tv_cmd->tvc_data_direction,
 572                         0, sg_ptr, tv_cmd->tvc_sgl_count,
 573                         sg_bidi_ptr, sg_no_bidi);
 574         if (rc < 0) {
 575                 transport_send_check_condition_and_sense(se_cmd,
 576                                 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0);
 577                 transport_generic_free_cmd(se_cmd, 0);
 578         }
 579 }
 580
 581 static void vhost_scsi_handle_vq(struct vhost_scsi *vs,
 582         struct vhost_virtqueue *vq)
 583 {
 584         struct tcm_vhost_tpg **vs_tpg;
 585         struct virtio_scsi_cmd_req v_req;
 586         struct tcm_vhost_tpg *tv_tpg;
 587         struct tcm_vhost_cmd *tv_cmd;
 588         u32 exp_data_len, data_first, data_num, data_direction;
 589         unsigned out, in, i;
 590         int head, ret;
 591         u8 target;
 592
 593         /*
 594          * We can handle the vq only after the endpoint is setup by calling the
 595          * VHOST_SCSI_SET_ENDPOINT ioctl.
 596          *
 597          * TODO: Check that we are running from vhost_worker which acts
 598          * as read-side critical section for vhost kind of RCU.
 599          * See the comments in struct vhost_virtqueue in drivers/vhost/vhost.h
 600          */
 601         vs_tpg = rcu_dereference_check(vq->private_data, 1);
 602         if (!vs_tpg)
 603                 return;
 604
 605         mutex_lock(&vq->mutex);
 606         vhost_disable_notify(&vs->dev, vq);
 607
 608         for (;;) {
 609                 head = vhost_get_vq_desc(&vs->dev, vq, vq->iov,
 610                                         ARRAY_SIZE(vq->iov), &out, &in,
 611                                         NULL, NULL);
 612                 pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n",
 613                                         head, out, in);
 614                 /* On error, stop handling until the next kick. */
 615                 if (unlikely(head < 0))
 616                         break;
 617                 /* Nothing new?  Wait for eventfd to tell us they refilled. */
 618                 if (head == vq->num) {
 619                         if (unlikely(vhost_enable_notify(&vs->dev, vq))) {
 620                                 vhost_disable_notify(&vs->dev, vq);
 621                                 continue;
 622                         }
 623                         break;
 624                 }
 625
 626 /* FIXME: BIDI operation */
 627                 if (out == 1 && in == 1) {
 628                         data_direction = DMA_NONE;
 629                         data_first = 0;
 630                         data_num = 0;
 631                 } else if (out == 1 && in > 1) {
 632                         data_direction = DMA_FROM_DEVICE;
 633                         data_first = out + 1;
 634                         data_num = in - 1;
 635                 } else if (out > 1 && in == 1) {
 636                         data_direction = DMA_TO_DEVICE;
 637                         data_first = 1;
 638                         data_num = out - 1;
 639                 } else {
 640                         vq_err(vq, "Invalid buffer layout out: %u in: %u\n",
 641                                         out, in);
 642                         break;
 643                 }
 644
 645                 /*
 646                  * Check for a sane resp buffer so we can report errors to
 647                  * the guest.
 648                  */
 649                 if (unlikely(vq->iov[out].iov_len !=
 650                                         sizeof(struct virtio_scsi_cmd_resp))) {
 651                         vq_err(vq, "Expecting virtio_scsi_cmd_resp, got %zu"
 652                                 " bytes\n", vq->iov[out].iov_len);
 653                         break;
 654                 }
 655
 656                 if (unlikely(vq->iov[0].iov_len != sizeof(v_req))) {
 657                         vq_err(vq, "Expecting virtio_scsi_cmd_req, got %zu"
 658                                 " bytes\n", vq->iov[0].iov_len);
 659                         break;
 660                 }
 661                 pr_debug("Calling __copy_from_user: vq->iov[0].iov_base: %p,"
 662                         " len: %zu\n", vq->iov[0].iov_base, sizeof(v_req));
 663                 ret = __copy_from_user(&v_req, vq->iov[0].iov_base,
 664                                 sizeof(v_req));
 665                 if (unlikely(ret)) {
 666                         vq_err(vq, "Faulted on virtio_scsi_cmd_req\n");
 667                         break;
 668                 }
 669
 670                 /* Extract the tpgt */
 671                 target = v_req.lun[1];
 672                 tv_tpg = ACCESS_ONCE(vs_tpg[target]);
 673
 674                 /* Target does not exist, fail the request */
 675                 if (unlikely(!tv_tpg)) {
 676                         struct virtio_scsi_cmd_resp __user *resp;
 677                         struct virtio_scsi_cmd_resp rsp;
 678
 679                         memset(&rsp, 0, sizeof(rsp));
 680                         rsp.response = VIRTIO_SCSI_S_BAD_TARGET;
 681                         resp = vq->iov[out].iov_base;
 682                         ret = __copy_to_user(resp, &rsp, sizeof(rsp));
 683                         if (!ret)
 684                                 vhost_add_used_and_signal(&vs->dev,
 685                                                           vq, head, 0);
 686                         else
 687                                 pr_err("Faulted on virtio_scsi_cmd_resp\n");
 688
 689                         continue;
 690                 }
 691
 692                 exp_data_len = 0;
 693                 for (i = 0; i < data_num; i++)
 694                         exp_data_len += vq->iov[data_first + i].iov_len;
 695
 696                 tv_cmd = vhost_scsi_allocate_cmd(tv_tpg, &v_req,
 697                                         exp_data_len, data_direction);
 698                 if (IS_ERR(tv_cmd)) {
 699                         vq_err(vq, "vhost_scsi_allocate_cmd failed %ld\n",
 700                                         PTR_ERR(tv_cmd));
 701                         break;
 702                 }
 703                 pr_debug("Allocated tv_cmd: %p exp_data_len: %d, data_direction"
 704                         ": %d\n", tv_cmd, exp_data_len, data_direction);
 705
 706                 tv_cmd->tvc_vhost = vs;
 707                 tv_cmd->tvc_vq = vq;
 708
 709                 if (unlikely(vq->iov[out].iov_len !=
 710                                 sizeof(struct virtio_scsi_cmd_resp))) {
 711                         vq_err(vq, "Expecting virtio_scsi_cmd_resp, got %zu"
 712                                 " bytes, out: %d, in: %d\n",
 713                                 vq->iov[out].iov_len, out, in);
 714                         break;
 715                 }
 716
 717                 tv_cmd->tvc_resp = vq->iov[out].iov_base;
 718
 719                 /*
 720                  * Copy in the recieved CDB descriptor into tv_cmd->tvc_cdb
 721                  * that will be used by tcm_vhost_new_cmd_map() and down into
 722                  * target_setup_cmd_from_cdb()
 723                  */
 724                 memcpy(tv_cmd->tvc_cdb, v_req.cdb, TCM_VHOST_MAX_CDB_SIZE);
 725                 /*
 726                  * Check that the recieved CDB size does not exceeded our
 727                  * hardcoded max for tcm_vhost
 728                  */
 729                 /* TODO what if cdb was too small for varlen cdb header? */
 730                 if (unlikely(scsi_command_size(tv_cmd->tvc_cdb) >
 731                                         TCM_VHOST_MAX_CDB_SIZE)) {
 732                         vq_err(vq, "Received SCSI CDB with command_size: %d that"
 733                                 " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
 734                                 scsi_command_size(tv_cmd->tvc_cdb),
 735                                 TCM_VHOST_MAX_CDB_SIZE);
 736                         break; /* TODO */
 737                 }
 738                 tv_cmd->tvc_lun = ((v_req.lun[2] << 8) | v_req.lun[3]) & 0x3FFF;
 739
 740                 pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n",
 741                         tv_cmd->tvc_cdb[0], tv_cmd->tvc_lun);
 742
 743                 if (data_direction != DMA_NONE) {
 744                         ret = vhost_scsi_map_iov_to_sgl(tv_cmd,
 745                                         &vq->iov[data_first], data_num,
 746                                         data_direction == DMA_TO_DEVICE);
 747                         if (unlikely(ret)) {
 748                                 vq_err(vq, "Failed to map iov to sgl\n");
 749                                 break; /* TODO */
 750                         }
 751                 }
 752
 753                 /*
 754                  * Save the descriptor from vhost_get_vq_desc() to be used to
 755                  * complete the virtio-scsi request in TCM callback context via
 756                  * tcm_vhost_queue_data_in() and tcm_vhost_queue_status()
 757                  */
 758                 tv_cmd->tvc_vq_desc = head;
 759                 /*
 760                  * Dispatch tv_cmd descriptor for cmwq execution in process
 761                  * context provided by tcm_vhost_workqueue.  This also ensures
 762                  * tv_cmd is executed on the same kworker CPU as this vhost
 763                  * thread to gain positive L2 cache locality effects..
 764                  */
 765                 INIT_WORK(&tv_cmd->work, tcm_vhost_submission_work);
 766                 queue_work(tcm_vhost_workqueue, &tv_cmd->work);
 767         }
 768
 769         mutex_unlock(&vq->mutex);
 770 }
 771
 772 static void vhost_scsi_ctl_handle_kick(struct vhost_work *work)
 773 {
 774         pr_debug("%s: The handling func for control queue.\n", __func__);
 775 }
 776
 777 static void vhost_scsi_evt_handle_kick(struct vhost_work *work)
 778 {
 779         pr_debug("%s: The handling func for event queue.\n", __func__);
 780 }
 781
 782 static void vhost_scsi_handle_kick(struct vhost_work *work)
 783 {
 784         struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
 785                                                 poll.work);
 786         struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
 787
 788         vhost_scsi_handle_vq(vs, vq);
 789 }
 790
 791 static void vhost_scsi_flush_vq(struct vhost_scsi *vs, int index)
 792 {
 793         vhost_poll_flush(&vs->dev.vqs[index].poll);
 794 }
 795
 796 static void vhost_scsi_flush(struct vhost_scsi *vs)
 797 {
 798         int i;
 799
 800         for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
 801                 vhost_scsi_flush_vq(vs, i);
 802         vhost_work_flush(&vs->dev, &vs->vs_completion_work);
 803 }
 804
 805 /*
 806  * Called from vhost_scsi_ioctl() context to walk the list of available
 807  * tcm_vhost_tpg with an active struct tcm_vhost_nexus
 808  */
 809 static int vhost_scsi_set_endpoint(
 810         struct vhost_scsi *vs,
 811         struct vhost_scsi_target *t)
 812 {
 813         struct tcm_vhost_tport *tv_tport;
 814         struct tcm_vhost_tpg *tv_tpg;
 815         struct tcm_vhost_tpg **vs_tpg;
 816         struct vhost_virtqueue *vq;
 817         int index, ret, i, len;
 818         bool match = false;
 819
 820         mutex_lock(&vs->dev.mutex);
 821         /* Verify that ring has been setup correctly. */
 822         for (index = 0; index < vs->dev.nvqs; ++index) {
 823                 /* Verify that ring has been setup correctly. */
 824                 if (!vhost_vq_access_ok(&vs->vqs[index])) {
 825                         mutex_unlock(&vs->dev.mutex);
 826                         return -EFAULT;
 827                 }
 828         }
 829
 830         len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET;
 831         vs_tpg = kzalloc(len, GFP_KERNEL);
 832         if (!vs_tpg) {
 833                 mutex_unlock(&vs->dev.mutex);
 834                 return -ENOMEM;
 835         }
 836         if (vs->vs_tpg)
 837                 memcpy(vs_tpg, vs->vs_tpg, len);
 838
 839         mutex_lock(&tcm_vhost_mutex);
 840         list_for_each_entry(tv_tpg, &tcm_vhost_list, tv_tpg_list) {
 841                 mutex_lock(&tv_tpg->tv_tpg_mutex);
 842                 if (!tv_tpg->tpg_nexus) {
 843                         mutex_unlock(&tv_tpg->tv_tpg_mutex);
 844                         continue;
 845                 }
 846                 if (tv_tpg->tv_tpg_vhost_count != 0) {
 847                         mutex_unlock(&tv_tpg->tv_tpg_mutex);
 848                         continue;
 849                 }
 850                 tv_tport = tv_tpg->tport;
 851
 852                 if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
 853                         if (vs->vs_tpg && vs->vs_tpg[tv_tpg->tport_tpgt]) {
 854                                 mutex_unlock(&tv_tpg->tv_tpg_mutex);
 855                                 mutex_unlock(&tcm_vhost_mutex);
 856                                 mutex_unlock(&vs->dev.mutex);
 857                                 kfree(vs_tpg);
 858                                 return -EEXIST;
 859                         }
 860                         tv_tpg->tv_tpg_vhost_count++;
 861                         vs_tpg[tv_tpg->tport_tpgt] = tv_tpg;
 862                         smp_mb__after_atomic_inc();
 863                         match = true;
 864                 }
 865                 mutex_unlock(&tv_tpg->tv_tpg_mutex);
 866         }
 867         mutex_unlock(&tcm_vhost_mutex);
 868
 869         if (match) {
 870                 memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
 871                        sizeof(vs->vs_vhost_wwpn));
 872                 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
 873                         vq = &vs->vqs[i];
 874                         /* Flushing the vhost_work acts as synchronize_rcu */
 875                         mutex_lock(&vq->mutex);
 876                         rcu_assign_pointer(vq->private_data, vs_tpg);
 877                         mutex_unlock(&vq->mutex);
 878                 }
 879                 ret = 0;
 880         } else {
 881                 ret = -EEXIST;
 882         }
 883
 884         /*
 885          * Act as synchronize_rcu to make sure access to
 886          * old vs->vs_tpg is finished.
 887          */
 888         vhost_scsi_flush(vs);
 889         kfree(vs->vs_tpg);
 890         vs->vs_tpg = vs_tpg;
 891
 892         mutex_unlock(&vs->dev.mutex);
 893         return ret;
 894 }
 895
 896 static int vhost_scsi_clear_endpoint(
 897         struct vhost_scsi *vs,
 898         struct vhost_scsi_target *t)
 899 {
 900         struct tcm_vhost_tport *tv_tport;
 901         struct tcm_vhost_tpg *tv_tpg;
 902         struct vhost_virtqueue *vq;
 903         bool match = false;
 904         int index, ret, i;
 905         u8 target;
 906
 907         mutex_lock(&vs->dev.mutex);
 908         /* Verify that ring has been setup correctly. */
 909         for (index = 0; index < vs->dev.nvqs; ++index) {
 910                 if (!vhost_vq_access_ok(&vs->vqs[index])) {
 911                         ret = -EFAULT;
 912                         goto err_dev;
 913                 }
 914         }
 915
 916         if (!vs->vs_tpg) {
 917                 mutex_unlock(&vs->dev.mutex);
 918                 return 0;
 919         }
 920
 921         for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
 922                 target = i;
 923                 tv_tpg = vs->vs_tpg[target];
 924                 if (!tv_tpg)
 925                         continue;
 926
 927                 mutex_lock(&tv_tpg->tv_tpg_mutex);
 928                 tv_tport = tv_tpg->tport;
 929                 if (!tv_tport) {
 930                         ret = -ENODEV;
 931                         goto err_tpg;
 932                 }
 933
 934                 if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
 935                         pr_warn("tv_tport->tport_name: %s, tv_tpg->tport_tpgt: %hu"
 936                                 " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
 937                                 tv_tport->tport_name, tv_tpg->tport_tpgt,
 938                                 t->vhost_wwpn, t->vhost_tpgt);
 939                         ret = -EINVAL;
 940                         goto err_tpg;
 941                 }
 942                 tv_tpg->tv_tpg_vhost_count--;
 943                 vs->vs_tpg[target] = NULL;
 944                 match = true;
 945                 mutex_unlock(&tv_tpg->tv_tpg_mutex);
 946         }
 947         if (match) {
 948                 for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
 949                         vq = &vs->vqs[i];
 950                         /* Flushing the vhost_work acts as synchronize_rcu */
 951                         mutex_lock(&vq->mutex);
 952                         rcu_assign_pointer(vq->private_data, NULL);
 953                         mutex_unlock(&vq->mutex);
 954                 }
 955         }
 956         /*
 957          * Act as synchronize_rcu to make sure access to
 958          * old vs->vs_tpg is finished.
 959          */
 960         vhost_scsi_flush(vs);
 961         kfree(vs->vs_tpg);
 962         vs->vs_tpg = NULL;
 963         mutex_unlock(&vs->dev.mutex);
 964
 965         return 0;
 966
 967 err_tpg:
 968         mutex_unlock(&tv_tpg->tv_tpg_mutex);
 969 err_dev:
 970         mutex_unlock(&vs->dev.mutex);
 971         return ret;
 972 }
 973
 974 static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features)
 975 {
 976         if (features & ~VHOST_SCSI_FEATURES)
 977                 return -EOPNOTSUPP;
 978
 979         mutex_lock(&vs->dev.mutex);
 980         if ((features & (1 << VHOST_F_LOG_ALL)) &&
 981             !vhost_log_access_ok(&vs->dev)) {
 982                 mutex_unlock(&vs->dev.mutex);
 983                 return -EFAULT;
 984         }
 985         vs->dev.acked_features = features;
 986         smp_wmb();
 987         vhost_scsi_flush(vs);
 988         mutex_unlock(&vs->dev.mutex);
 989         return 0;
 990 }
 991
 992 static int vhost_scsi_open(struct inode *inode, struct file *f)
 993 {
 994         struct vhost_scsi *s;
 995         int r, i;
 996
 997         s = kzalloc(sizeof(*s), GFP_KERNEL);
 998         if (!s)
 999                 return -ENOMEM;
1000
1001         vhost_work_init(&s->vs_completion_work, vhost_scsi_complete_cmd_work);
1002
1003         s->vqs[VHOST_SCSI_VQ_CTL].handle_kick = vhost_scsi_ctl_handle_kick;
1004         s->vqs[VHOST_SCSI_VQ_EVT].handle_kick = vhost_scsi_evt_handle_kick;
1005         for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++)
1006                 s->vqs[i].handle_kick = vhost_scsi_handle_kick;
1007         r = vhost_dev_init(&s->dev, s->vqs, VHOST_SCSI_MAX_VQ);
1008         if (r < 0) {
1009                 kfree(s);
1010                 return r;
1011         }
1012
1013         f->private_data = s;
1014         return 0;
1015 }
1016
1017 static int vhost_scsi_release(struct inode *inode, struct file *f)
1018 {
1019         struct vhost_scsi *s = f->private_data;
1020         struct vhost_scsi_target t;
1021
1022         mutex_lock(&s->dev.mutex);
1023         memcpy(t.vhost_wwpn, s->vs_vhost_wwpn, sizeof(t.vhost_wwpn));
1024         mutex_unlock(&s->dev.mutex);
1025         vhost_scsi_clear_endpoint(s, &t);
1026         vhost_dev_stop(&s->dev);
1027         vhost_dev_cleanup(&s->dev, false);
1028         kfree(s);
1029         return 0;
1030 }
1031
1032 static long vhost_scsi_ioctl(struct file *f, unsigned int ioctl,
1033                                 unsigned long arg)
1034 {
1035         struct vhost_scsi *vs = f->private_data;
1036         struct vhost_scsi_target backend;
1037         void __user *argp = (void __user *)arg;
1038         u64 __user *featurep = argp;
1039         u64 features;
1040         int r, abi_version = VHOST_SCSI_ABI_VERSION;
1041
1042         switch (ioctl) {
1043         case VHOST_SCSI_SET_ENDPOINT:
1044                 if (copy_from_user(&backend, argp, sizeof backend))
1045                         return -EFAULT;
1046                 if (backend.reserved != 0)
1047                         return -EOPNOTSUPP;
1048
1049                 return vhost_scsi_set_endpoint(vs, &backend);
1050         case VHOST_SCSI_CLEAR_ENDPOINT:
1051                 if (copy_from_user(&backend, argp, sizeof backend))
1052                         return -EFAULT;
1053                 if (backend.reserved != 0)
1054                         return -EOPNOTSUPP;
1055
1056                 return vhost_scsi_clear_endpoint(vs, &backend);
1057         case VHOST_SCSI_GET_ABI_VERSION:
1058                 if (copy_to_user(argp, &abi_version, sizeof abi_version))
1059                         return -EFAULT;
1060                 return 0;
1061         case VHOST_GET_FEATURES:
1062                 features = VHOST_SCSI_FEATURES;
1063                 if (copy_to_user(featurep, &features, sizeof features))
1064                         return -EFAULT;
1065                 return 0;
1066         case VHOST_SET_FEATURES:
1067                 if (copy_from_user(&features, featurep, sizeof features))
1068                         return -EFAULT;
1069                 return vhost_scsi_set_features(vs, features);
1070         default:
1071                 mutex_lock(&vs->dev.mutex);
1072                 r = vhost_dev_ioctl(&vs->dev, ioctl, argp);
1073                 /* TODO: flush backend after dev ioctl. */
1074                 if (r == -ENOIOCTLCMD)
1075                         r = vhost_vring_ioctl(&vs->dev, ioctl, argp);
1076                 mutex_unlock(&vs->dev.mutex);
1077                 return r;
1078         }
1079 }
1080
1081 #ifdef CONFIG_COMPAT
1082 static long vhost_scsi_compat_ioctl(struct file *f, unsigned int ioctl,
1083                                 unsigned long arg)
1084 {
1085         return vhost_scsi_ioctl(f, ioctl, (unsigned long)compat_ptr(arg));
1086 }
1087 #endif
1088
1089 static const struct file_operations vhost_scsi_fops = {
1090         .owner          = THIS_MODULE,
1091         .release        = vhost_scsi_release,
1092         .unlocked_ioctl = vhost_scsi_ioctl,
1093 #ifdef CONFIG_COMPAT
1094         .compat_ioctl   = vhost_scsi_compat_ioctl,
1095 #endif
1096         .open           = vhost_scsi_open,
1097         .llseek         = noop_llseek,
1098 };
1099
1100 static struct miscdevice vhost_scsi_misc = {
1101         MISC_DYNAMIC_MINOR,
1102         "vhost-scsi",
1103         &vhost_scsi_fops,
1104 };
1105
1106 static int __init vhost_scsi_register(void)
1107 {
1108         return misc_register(&vhost_scsi_misc);
1109 }
1110
1111 static int vhost_scsi_deregister(void)
1112 {
1113         return misc_deregister(&vhost_scsi_misc);
1114 }
1115
1116 static char *tcm_vhost_dump_proto_id(struct tcm_vhost_tport *tport)
1117 {
1118         switch (tport->tport_proto_id) {
1119         case SCSI_PROTOCOL_SAS:
1120                 return "SAS";
1121         case SCSI_PROTOCOL_FCP:
1122                 return "FCP";
1123         case SCSI_PROTOCOL_ISCSI:
1124                 return "iSCSI";
1125         default:
1126                 break;
1127         }
1128
1129         return "Unknown";
1130 }
1131
1132 static int tcm_vhost_port_link(struct se_portal_group *se_tpg,
1133         struct se_lun *lun)
1134 {
1135         struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg,
1136                                 struct tcm_vhost_tpg, se_tpg);
1137
1138         mutex_lock(&tv_tpg->tv_tpg_mutex);
1139         tv_tpg->tv_tpg_port_count++;
1140         mutex_unlock(&tv_tpg->tv_tpg_mutex);
1141
1142         return 0;
1143 }
1144
1145 static void tcm_vhost_port_unlink(struct se_portal_group *se_tpg,
1146         struct se_lun *se_lun)
1147 {
1148         struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg,
1149                                 struct tcm_vhost_tpg, se_tpg);
1150
1151         mutex_lock(&tv_tpg->tv_tpg_mutex);
1152         tv_tpg->tv_tpg_port_count--;
1153         mutex_unlock(&tv_tpg->tv_tpg_mutex);
1154 }
1155
1156 static struct se_node_acl *tcm_vhost_make_nodeacl(
1157         struct se_portal_group *se_tpg,
1158         struct config_group *group,
1159         const char *name)
1160 {
1161         struct se_node_acl *se_nacl, *se_nacl_new;
1162         struct tcm_vhost_nacl *nacl;
1163         u64 wwpn = 0;
1164         u32 nexus_depth;
1165
1166         /* tcm_vhost_parse_wwn(name, &wwpn, 1) < 0)
1167                 return ERR_PTR(-EINVAL); */
1168         se_nacl_new = tcm_vhost_alloc_fabric_acl(se_tpg);
1169         if (!se_nacl_new)
1170                 return ERR_PTR(-ENOMEM);
1171
1172         nexus_depth = 1;
1173         /*
1174          * se_nacl_new may be released by core_tpg_add_initiator_node_acl()
1175          * when converting a NodeACL from demo mode -> explict
1176          */
1177         se_nacl = core_tpg_add_initiator_node_acl(se_tpg, se_nacl_new,
1178                                 name, nexus_depth);
1179         if (IS_ERR(se_nacl)) {
1180                 tcm_vhost_release_fabric_acl(se_tpg, se_nacl_new);
1181                 return se_nacl;
1182         }
1183         /*
1184          * Locate our struct tcm_vhost_nacl and set the FC Nport WWPN
1185          */
1186         nacl = container_of(se_nacl, struct tcm_vhost_nacl, se_node_acl);
1187         nacl->iport_wwpn = wwpn;
1188
1189         return se_nacl;
1190 }
1191
1192 static void tcm_vhost_drop_nodeacl(struct se_node_acl *se_acl)
1193 {
1194         struct tcm_vhost_nacl *nacl = container_of(se_acl,
1195                                 struct tcm_vhost_nacl, se_node_acl);
1196         core_tpg_del_initiator_node_acl(se_acl->se_tpg, se_acl, 1);
1197         kfree(nacl);
1198 }
1199
1200 static int tcm_vhost_make_nexus(struct tcm_vhost_tpg *tv_tpg,
1201         const char *name)
1202 {
1203         struct se_portal_group *se_tpg;
1204         struct tcm_vhost_nexus *tv_nexus;
1205
1206         mutex_lock(&tv_tpg->tv_tpg_mutex);
1207         if (tv_tpg->tpg_nexus) {
1208                 mutex_unlock(&tv_tpg->tv_tpg_mutex);
1209                 pr_debug("tv_tpg->tpg_nexus already exists\n");
1210                 return -EEXIST;
1211         }
1212         se_tpg = &tv_tpg->se_tpg;
1213
1214         tv_nexus = kzalloc(sizeof(struct tcm_vhost_nexus), GFP_KERNEL);
1215         if (!tv_nexus) {
1216                 mutex_unlock(&tv_tpg->tv_tpg_mutex);
1217                 pr_err("Unable to allocate struct tcm_vhost_nexus\n");
1218                 return -ENOMEM;
1219         }
1220         /*
1221          *  Initialize the struct se_session pointer
1222          */
1223         tv_nexus->tvn_se_sess = transport_init_session();
1224         if (IS_ERR(tv_nexus->tvn_se_sess)) {
1225                 mutex_unlock(&tv_tpg->tv_tpg_mutex);
1226                 kfree(tv_nexus);
1227                 return -ENOMEM;
1228         }
1229         /*
1230          * Since we are running in 'demo mode' this call with generate a
1231          * struct se_node_acl for the tcm_vhost struct se_portal_group with
1232          * the SCSI Initiator port name of the passed configfs group 'name'.
1233          */
1234         tv_nexus->tvn_se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
1235                                 se_tpg, (unsigned char *)name);
1236         if (!tv_nexus->tvn_se_sess->se_node_acl) {
1237                 mutex_unlock(&tv_tpg->tv_tpg_mutex);
1238                 pr_debug("core_tpg_check_initiator_node_acl() failed"
1239                                 " for %s\n", name);
1240                 transport_free_session(tv_nexus->tvn_se_sess);
1241                 kfree(tv_nexus);
1242                 return -ENOMEM;
1243         }
1244         /*
1245          * Now register the TCM vhost virtual I_T Nexus as active with the
1246          * call to __transport_register_session()
1247          */
1248         __transport_register_session(se_tpg, tv_nexus->tvn_se_sess->se_node_acl,
1249                         tv_nexus->tvn_se_sess, tv_nexus);
1250         tv_tpg->tpg_nexus = tv_nexus;
1251
1252         mutex_unlock(&tv_tpg->tv_tpg_mutex);
1253         return 0;
1254 }
1255
1256 static int tcm_vhost_drop_nexus(struct tcm_vhost_tpg *tpg)
1257 {
1258         struct se_session *se_sess;
1259         struct tcm_vhost_nexus *tv_nexus;
1260
1261         mutex_lock(&tpg->tv_tpg_mutex);
1262         tv_nexus = tpg->tpg_nexus;
1263         if (!tv_nexus) {
1264                 mutex_unlock(&tpg->tv_tpg_mutex);
1265                 return -ENODEV;
1266         }
1267
1268         se_sess = tv_nexus->tvn_se_sess;
1269         if (!se_sess) {
1270                 mutex_unlock(&tpg->tv_tpg_mutex);
1271                 return -ENODEV;
1272         }
1273
1274         if (tpg->tv_tpg_port_count != 0) {
1275                 mutex_unlock(&tpg->tv_tpg_mutex);
1276                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
1277                         " active TPG port count: %d\n",
1278                         tpg->tv_tpg_port_count);
1279                 return -EBUSY;
1280         }
1281
1282         if (tpg->tv_tpg_vhost_count != 0) {
1283                 mutex_unlock(&tpg->tv_tpg_mutex);
1284                 pr_err("Unable to remove TCM_vhost I_T Nexus with"
1285                         " active TPG vhost count: %d\n",
1286                         tpg->tv_tpg_vhost_count);
1287                 return -EBUSY;
1288         }
1289
1290         pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated"
1291                 " %s Initiator Port: %s\n", tcm_vhost_dump_proto_id(tpg->tport),
1292                 tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1293         /*
1294          * Release the SCSI I_T Nexus to the emulated vhost Target Port
1295          */
1296         transport_deregister_session(tv_nexus->tvn_se_sess);
1297         tpg->tpg_nexus = NULL;
1298         mutex_unlock(&tpg->tv_tpg_mutex);
1299
1300         kfree(tv_nexus);
1301         return 0;
1302 }
1303
1304 static ssize_t tcm_vhost_tpg_show_nexus(struct se_portal_group *se_tpg,
1305         char *page)
1306 {
1307         struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg,
1308                                 struct tcm_vhost_tpg, se_tpg);
1309         struct tcm_vhost_nexus *tv_nexus;
1310         ssize_t ret;
1311
1312         mutex_lock(&tv_tpg->tv_tpg_mutex);
1313         tv_nexus = tv_tpg->tpg_nexus;
1314         if (!tv_nexus) {
1315                 mutex_unlock(&tv_tpg->tv_tpg_mutex);
1316                 return -ENODEV;
1317         }
1318         ret = snprintf(page, PAGE_SIZE, "%s\n",
1319                         tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1320         mutex_unlock(&tv_tpg->tv_tpg_mutex);
1321
1322         return ret;
1323 }
1324
1325 static ssize_t tcm_vhost_tpg_store_nexus(struct se_portal_group *se_tpg,
1326         const char *page,
1327         size_t count)
1328 {
1329         struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg,
1330                                 struct tcm_vhost_tpg, se_tpg);
1331         struct tcm_vhost_tport *tport_wwn = tv_tpg->tport;
1332         unsigned char i_port[TCM_VHOST_NAMELEN], *ptr, *port_ptr;
1333         int ret;
1334         /*
1335          * Shutdown the active I_T nexus if 'NULL' is passed..
1336          */
1337         if (!strncmp(page, "NULL", 4)) {
1338                 ret = tcm_vhost_drop_nexus(tv_tpg);
1339                 return (!ret) ? count : ret;
1340         }
1341         /*
1342          * Otherwise make sure the passed virtual Initiator port WWN matches
1343          * the fabric protocol_id set in tcm_vhost_make_tport(), and call
1344          * tcm_vhost_make_nexus().
1345          */
1346         if (strlen(page) >= TCM_VHOST_NAMELEN) {
1347                 pr_err("Emulated NAA Sas Address: %s, exceeds"
1348                                 " max: %d\n", page, TCM_VHOST_NAMELEN);
1349                 return -EINVAL;
1350         }
1351         snprintf(&i_port[0], TCM_VHOST_NAMELEN, "%s", page);
1352
1353         ptr = strstr(i_port, "naa.");
1354         if (ptr) {
1355                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
1356                         pr_err("Passed SAS Initiator Port %s does not"
1357                                 " match target port protoid: %s\n", i_port,
1358                                 tcm_vhost_dump_proto_id(tport_wwn));
1359                         return -EINVAL;
1360                 }
1361                 port_ptr = &i_port[0];
1362                 goto check_newline;
1363         }
1364         ptr = strstr(i_port, "fc.");
1365         if (ptr) {
1366                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
1367                         pr_err("Passed FCP Initiator Port %s does not"
1368                                 " match target port protoid: %s\n", i_port,
1369                                 tcm_vhost_dump_proto_id(tport_wwn));
1370                         return -EINVAL;
1371                 }
1372                 port_ptr = &i_port[3]; /* Skip over "fc." */
1373                 goto check_newline;
1374         }
1375         ptr = strstr(i_port, "iqn.");
1376         if (ptr) {
1377                 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
1378                         pr_err("Passed iSCSI Initiator Port %s does not"
1379                                 " match target port protoid: %s\n", i_port,
1380                                 tcm_vhost_dump_proto_id(tport_wwn));
1381                         return -EINVAL;
1382                 }
1383                 port_ptr = &i_port[0];
1384                 goto check_newline;
1385         }
1386         pr_err("Unable to locate prefix for emulated Initiator Port:"
1387                         " %s\n", i_port);
1388         return -EINVAL;
1389         /*
1390          * Clear any trailing newline for the NAA WWN
1391          */
1392 check_newline:
1393         if (i_port[strlen(i_port)-1] == '\n')
1394                 i_port[strlen(i_port)-1] = '\0';
1395
1396         ret = tcm_vhost_make_nexus(tv_tpg, port_ptr);
1397         if (ret < 0)
1398                 return ret;
1399
1400         return count;
1401 }
1402
1403 TF_TPG_BASE_ATTR(tcm_vhost, nexus, S_IRUGO | S_IWUSR);
1404
1405 static struct configfs_attribute *tcm_vhost_tpg_attrs[] = {
1406         &tcm_vhost_tpg_nexus.attr,
1407         NULL,
1408 };
1409
1410 static struct se_portal_group *tcm_vhost_make_tpg(struct se_wwn *wwn,
1411         struct config_group *group,
1412         const char *name)
1413 {
1414         struct tcm_vhost_tport *tport = container_of(wwn,
1415                         struct tcm_vhost_tport, tport_wwn);
1416
1417         struct tcm_vhost_tpg *tpg;
1418         unsigned long tpgt;
1419         int ret;
1420
1421         if (strstr(name, "tpgt_") != name)
1422                 return ERR_PTR(-EINVAL);
1423         if (kstrtoul(name + 5, 10, &tpgt) || tpgt > UINT_MAX)
1424                 return ERR_PTR(-EINVAL);
1425
1426         tpg = kzalloc(sizeof(struct tcm_vhost_tpg), GFP_KERNEL);
1427         if (!tpg) {
1428                 pr_err("Unable to allocate struct tcm_vhost_tpg");
1429                 return ERR_PTR(-ENOMEM);
1430         }
1431         mutex_init(&tpg->tv_tpg_mutex);
1432         INIT_LIST_HEAD(&tpg->tv_tpg_list);
1433         tpg->tport = tport;
1434         tpg->tport_tpgt = tpgt;
1435
1436         ret = core_tpg_register(&tcm_vhost_fabric_configfs->tf_ops, wwn,
1437                                 &tpg->se_tpg, tpg, TRANSPORT_TPG_TYPE_NORMAL);
1438         if (ret < 0) {
1439                 kfree(tpg);
1440                 return NULL;
1441         }
1442         mutex_lock(&tcm_vhost_mutex);
1443         list_add_tail(&tpg->tv_tpg_list, &tcm_vhost_list);
1444         mutex_unlock(&tcm_vhost_mutex);
1445
1446         return &tpg->se_tpg;
1447 }
1448
1449 static void tcm_vhost_drop_tpg(struct se_portal_group *se_tpg)
1450 {
1451         struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1452                                 struct tcm_vhost_tpg, se_tpg);
1453
1454         mutex_lock(&tcm_vhost_mutex);
1455         list_del(&tpg->tv_tpg_list);
1456         mutex_unlock(&tcm_vhost_mutex);
1457         /*
1458          * Release the virtual I_T Nexus for this vhost TPG
1459          */
1460         tcm_vhost_drop_nexus(tpg);
1461         /*
1462          * Deregister the se_tpg from TCM..
1463          */
1464         core_tpg_deregister(se_tpg);
1465         kfree(tpg);
1466 }
1467
1468 static struct se_wwn *tcm_vhost_make_tport(struct target_fabric_configfs *tf,
1469         struct config_group *group,
1470         const char *name)
1471 {
1472         struct tcm_vhost_tport *tport;
1473         char *ptr;
1474         u64 wwpn = 0;
1475         int off = 0;
1476
1477         /* if (tcm_vhost_parse_wwn(name, &wwpn, 1) < 0)
1478                 return ERR_PTR(-EINVAL); */
1479
1480         tport = kzalloc(sizeof(struct tcm_vhost_tport), GFP_KERNEL);
1481         if (!tport) {
1482                 pr_err("Unable to allocate struct tcm_vhost_tport");
1483                 return ERR_PTR(-ENOMEM);
1484         }
1485         tport->tport_wwpn = wwpn;
1486         /*
1487          * Determine the emulated Protocol Identifier and Target Port Name
1488          * based on the incoming configfs directory name.
1489          */
1490         ptr = strstr(name, "naa.");
1491         if (ptr) {
1492                 tport->tport_proto_id = SCSI_PROTOCOL_SAS;
1493                 goto check_len;
1494         }
1495         ptr = strstr(name, "fc.");
1496         if (ptr) {
1497                 tport->tport_proto_id = SCSI_PROTOCOL_FCP;
1498                 off = 3; /* Skip over "fc." */
1499                 goto check_len;
1500         }
1501         ptr = strstr(name, "iqn.");
1502         if (ptr) {
1503                 tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
1504                 goto check_len;
1505         }
1506
1507         pr_err("Unable to locate prefix for emulated Target Port:"
1508                         " %s\n", name);
1509         kfree(tport);
1510         return ERR_PTR(-EINVAL);
1511
1512 check_len:
1513         if (strlen(name) >= TCM_VHOST_NAMELEN) {
1514                 pr_err("Emulated %s Address: %s, exceeds"
1515                         " max: %d\n", name, tcm_vhost_dump_proto_id(tport),
1516                         TCM_VHOST_NAMELEN);
1517                 kfree(tport);
1518                 return ERR_PTR(-EINVAL);
1519         }
1520         snprintf(&tport->tport_name[0], TCM_VHOST_NAMELEN, "%s", &name[off]);
1521
1522         pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target"
1523                 " %s Address: %s\n", tcm_vhost_dump_proto_id(tport), name);
1524
1525         return &tport->tport_wwn;
1526 }
1527
1528 static void tcm_vhost_drop_tport(struct se_wwn *wwn)
1529 {
1530         struct tcm_vhost_tport *tport = container_of(wwn,
1531                                 struct tcm_vhost_tport, tport_wwn);
1532
1533         pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target"
1534                 " %s Address: %s\n", tcm_vhost_dump_proto_id(tport),
1535                 tport->tport_name);
1536
1537         kfree(tport);
1538 }
1539
1540 static ssize_t tcm_vhost_wwn_show_attr_version(
1541         struct target_fabric_configfs *tf,
1542         char *page)
1543 {
1544         return sprintf(page, "TCM_VHOST fabric module %s on %s/%s"
1545                 "on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname,
1546                 utsname()->machine);
1547 }
1548
1549 TF_WWN_ATTR_RO(tcm_vhost, version);
1550
1551 static struct configfs_attribute *tcm_vhost_wwn_attrs[] = {
1552         &tcm_vhost_wwn_version.attr,
1553         NULL,
1554 };
1555
1556 static struct target_core_fabric_ops tcm_vhost_ops = {
1557         .get_fabric_name                = tcm_vhost_get_fabric_name,
1558         .get_fabric_proto_ident         = tcm_vhost_get_fabric_proto_ident,
1559         .tpg_get_wwn                    = tcm_vhost_get_fabric_wwn,
1560         .tpg_get_tag                    = tcm_vhost_get_tag,
1561         .tpg_get_default_depth          = tcm_vhost_get_default_depth,
1562         .tpg_get_pr_transport_id        = tcm_vhost_get_pr_transport_id,
1563         .tpg_get_pr_transport_id_len    = tcm_vhost_get_pr_transport_id_len,
1564         .tpg_parse_pr_out_transport_id  = tcm_vhost_parse_pr_out_transport_id,
1565         .tpg_check_demo_mode            = tcm_vhost_check_true,
1566         .tpg_check_demo_mode_cache      = tcm_vhost_check_true,
1567         .tpg_check_demo_mode_write_protect = tcm_vhost_check_false,
1568         .tpg_check_prod_mode_write_protect = tcm_vhost_check_false,
1569         .tpg_alloc_fabric_acl           = tcm_vhost_alloc_fabric_acl,
1570         .tpg_release_fabric_acl         = tcm_vhost_release_fabric_acl,
1571         .tpg_get_inst_index             = tcm_vhost_tpg_get_inst_index,
1572         .release_cmd                    = tcm_vhost_release_cmd,
1573         .shutdown_session               = tcm_vhost_shutdown_session,
1574         .close_session                  = tcm_vhost_close_session,
1575         .sess_get_index                 = tcm_vhost_sess_get_index,
1576         .sess_get_initiator_sid         = NULL,
1577         .write_pending                  = tcm_vhost_write_pending,
1578         .write_pending_status           = tcm_vhost_write_pending_status,
1579         .set_default_node_attributes    = tcm_vhost_set_default_node_attrs,
1580         .get_task_tag                   = tcm_vhost_get_task_tag,
1581         .get_cmd_state                  = tcm_vhost_get_cmd_state,
1582         .queue_data_in                  = tcm_vhost_queue_data_in,
1583         .queue_status                   = tcm_vhost_queue_status,
1584         .queue_tm_rsp                   = tcm_vhost_queue_tm_rsp,
1585         /*
1586          * Setup callers for generic logic in target_core_fabric_configfs.c
1587          */
1588         .fabric_make_wwn                = tcm_vhost_make_tport,
1589         .fabric_drop_wwn                = tcm_vhost_drop_tport,
1590         .fabric_make_tpg                = tcm_vhost_make_tpg,
1591         .fabric_drop_tpg                = tcm_vhost_drop_tpg,
1592         .fabric_post_link               = tcm_vhost_port_link,
1593         .fabric_pre_unlink              = tcm_vhost_port_unlink,
1594         .fabric_make_np                 = NULL,
1595         .fabric_drop_np                 = NULL,
1596         .fabric_make_nodeacl            = tcm_vhost_make_nodeacl,
1597         .fabric_drop_nodeacl            = tcm_vhost_drop_nodeacl,
1598 };
1599
1600 static int tcm_vhost_register_configfs(void)
1601 {
1602         struct target_fabric_configfs *fabric;
1603         int ret;
1604
1605         pr_debug("TCM_VHOST fabric module %s on %s/%s"
1606                 " on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname,
1607                 utsname()->machine);
1608         /*
1609          * Register the top level struct config_item_type with TCM core
1610          */
1611         fabric = target_fabric_configfs_init(THIS_MODULE, "vhost");
1612         if (IS_ERR(fabric)) {
1613                 pr_err("target_fabric_configfs_init() failed\n");
1614                 return PTR_ERR(fabric);
1615         }
1616         /*
1617          * Setup fabric->tf_ops from our local tcm_vhost_ops
1618          */
1619         fabric->tf_ops = tcm_vhost_ops;
1620         /*
1621          * Setup default attribute lists for various fabric->tf_cit_tmpl
1622          */
1623         TF_CIT_TMPL(fabric)->tfc_wwn_cit.ct_attrs = tcm_vhost_wwn_attrs;
1624         TF_CIT_TMPL(fabric)->tfc_tpg_base_cit.ct_attrs = tcm_vhost_tpg_attrs;
1625         TF_CIT_TMPL(fabric)->tfc_tpg_attrib_cit.ct_attrs = NULL;
1626         TF_CIT_TMPL(fabric)->tfc_tpg_param_cit.ct_attrs = NULL;
1627         TF_CIT_TMPL(fabric)->tfc_tpg_np_base_cit.ct_attrs = NULL;
1628         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_base_cit.ct_attrs = NULL;
1629         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_attrib_cit.ct_attrs = NULL;
1630         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_auth_cit.ct_attrs = NULL;
1631         TF_CIT_TMPL(fabric)->tfc_tpg_nacl_param_cit.ct_attrs = NULL;
1632         /*
1633          * Register the fabric for use within TCM
1634          */
1635         ret = target_fabric_configfs_register(fabric);
1636         if (ret < 0) {
1637                 pr_err("target_fabric_configfs_register() failed"
1638                                 " for TCM_VHOST\n");
1639                 return ret;
1640         }
1641         /*
1642          * Setup our local pointer to *fabric
1643          */
1644         tcm_vhost_fabric_configfs = fabric;
1645         pr_debug("TCM_VHOST[0] - Set fabric -> tcm_vhost_fabric_configfs\n");
1646         return 0;
1647 };
1648
1649 static void tcm_vhost_deregister_configfs(void)
1650 {
1651         if (!tcm_vhost_fabric_configfs)
1652                 return;
1653
1654         target_fabric_configfs_deregister(tcm_vhost_fabric_configfs);
1655         tcm_vhost_fabric_configfs = NULL;
1656         pr_debug("TCM_VHOST[0] - Cleared tcm_vhost_fabric_configfs\n");
1657 };
1658
1659 static int __init tcm_vhost_init(void)
1660 {
1661         int ret = -ENOMEM;
1662         /*
1663          * Use our own dedicated workqueue for submitting I/O into
1664          * target core to avoid contention within system_wq.
1665          */
1666         tcm_vhost_workqueue = alloc_workqueue("tcm_vhost", 0, 0);
1667         if (!tcm_vhost_workqueue)
1668                 goto out;
1669
1670         ret = vhost_scsi_register();
1671         if (ret < 0)
1672                 goto out_destroy_workqueue;
1673
1674         ret = tcm_vhost_register_configfs();
1675         if (ret < 0)
1676                 goto out_vhost_scsi_deregister;
1677
1678         return 0;
1679
1680 out_vhost_scsi_deregister:
1681         vhost_scsi_deregister();
1682 out_destroy_workqueue:
1683         destroy_workqueue(tcm_vhost_workqueue);
1684 out:
1685         return ret;
1686 };
1687
1688 static void tcm_vhost_exit(void)
1689 {
1690         tcm_vhost_deregister_configfs();
1691         vhost_scsi_deregister();
1692         destroy_workqueue(tcm_vhost_workqueue);
1693 };
1694
1695 MODULE_DESCRIPTION("TCM_VHOST series fabric driver");
1696 MODULE_LICENSE("GPL");
1697 module_init(tcm_vhost_init);
1698 module_exit(tcm_vhost_exit);