linux/drivers/vhost/tcm_vhost.c
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   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
  57enum {
  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 */
  68enum {
  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
  75struct 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 */
  88static struct target_fabric_configfs *tcm_vhost_fabric_configfs;
  89
  90static struct workqueue_struct *tcm_vhost_workqueue;
  91
  92/* Global spinlock to protect tcm_vhost TPG list for vhost IOCTL access */
  93static DEFINE_MUTEX(tcm_vhost_mutex);
  94static LIST_HEAD(tcm_vhost_list);
  95
  96static 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
 102static int tcm_vhost_check_true(struct se_portal_group *se_tpg)
 103{
 104        return 1;
 105}
 106
 107static int tcm_vhost_check_false(struct se_portal_group *se_tpg)
 108{
 109        return 0;
 110}
 111
 112static char *tcm_vhost_get_fabric_name(void)
 113{
 114        return "vhost";
 115}
 116
 117static 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
 139static 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
 148static 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
 155static u32 tcm_vhost_get_default_depth(struct se_portal_group *se_tpg)
 156{
 157        return 1;
 158}
 159
 160static 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
 190static 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
 219static 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
 248static 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
 262static 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
 270static u32 tcm_vhost_tpg_get_inst_index(struct se_portal_group *se_tpg)
 271{
 272        return 1;
 273}
 274
 275static void tcm_vhost_release_cmd(struct se_cmd *se_cmd)
 276{
 277        return;
 278}
 279
 280static int tcm_vhost_shutdown_session(struct se_session *se_sess)
 281{
 282        return 0;
 283}
 284
 285static void tcm_vhost_close_session(struct se_session *se_sess)
 286{
 287        return;
 288}
 289
 290static u32 tcm_vhost_sess_get_index(struct se_session *se_sess)
 291{
 292        return 0;
 293}
 294
 295static 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
 302static int tcm_vhost_write_pending_status(struct se_cmd *se_cmd)
 303{
 304        return 0;
 305}
 306
 307static void tcm_vhost_set_default_node_attrs(struct se_node_acl *nacl)
 308{
 309        return;
 310}
 311
 312static u32 tcm_vhost_get_task_tag(struct se_cmd *se_cmd)
 313{
 314        return 0;
 315}
 316
 317static int tcm_vhost_get_cmd_state(struct se_cmd *se_cmd)
 318{
 319        return 0;
 320}
 321
 322static 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
 331static 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
 339static 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
 347static int tcm_vhost_queue_tm_rsp(struct se_cmd *se_cmd)
 348{
 349        return 0;
 350}
 351
 352static 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 */
 375static 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
 421static 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 */
 455static 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
 495out:
 496        kfree(pages);
 497        return ret;
 498}
 499
 500static 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
 545static 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
 581static void vhost_scsi_send_bad_target(struct vhost_scsi *vs,
 582        struct vhost_virtqueue *vq, int head, unsigned out)
 583{
 584        struct virtio_scsi_cmd_resp __user *resp;
 585        struct virtio_scsi_cmd_resp rsp;
 586        int ret;
 587
 588        memset(&rsp, 0, sizeof(rsp));
 589        rsp.response = VIRTIO_SCSI_S_BAD_TARGET;
 590        resp = vq->iov[out].iov_base;
 591        ret = __copy_to_user(resp, &rsp, sizeof(rsp));
 592        if (!ret)
 593                vhost_add_used_and_signal(&vs->dev, vq, head, 0);
 594        else
 595                pr_err("Faulted on virtio_scsi_cmd_resp\n");
 596}
 597
 598static void vhost_scsi_handle_vq(struct vhost_scsi *vs,
 599        struct vhost_virtqueue *vq)
 600{
 601        struct tcm_vhost_tpg **vs_tpg;
 602        struct virtio_scsi_cmd_req v_req;
 603        struct tcm_vhost_tpg *tv_tpg;
 604        struct tcm_vhost_cmd *tv_cmd;
 605        u32 exp_data_len, data_first, data_num, data_direction;
 606        unsigned out, in, i;
 607        int head, ret;
 608        u8 target;
 609
 610        /*
 611         * We can handle the vq only after the endpoint is setup by calling the
 612         * VHOST_SCSI_SET_ENDPOINT ioctl.
 613         *
 614         * TODO: Check that we are running from vhost_worker which acts
 615         * as read-side critical section for vhost kind of RCU.
 616         * See the comments in struct vhost_virtqueue in drivers/vhost/vhost.h
 617         */
 618        vs_tpg = rcu_dereference_check(vq->private_data, 1);
 619        if (!vs_tpg)
 620                return;
 621
 622        mutex_lock(&vq->mutex);
 623        vhost_disable_notify(&vs->dev, vq);
 624
 625        for (;;) {
 626                head = vhost_get_vq_desc(&vs->dev, vq, vq->iov,
 627                                        ARRAY_SIZE(vq->iov), &out, &in,
 628                                        NULL, NULL);
 629                pr_debug("vhost_get_vq_desc: head: %d, out: %u in: %u\n",
 630                                        head, out, in);
 631                /* On error, stop handling until the next kick. */
 632                if (unlikely(head < 0))
 633                        break;
 634                /* Nothing new?  Wait for eventfd to tell us they refilled. */
 635                if (head == vq->num) {
 636                        if (unlikely(vhost_enable_notify(&vs->dev, vq))) {
 637                                vhost_disable_notify(&vs->dev, vq);
 638                                continue;
 639                        }
 640                        break;
 641                }
 642
 643/* FIXME: BIDI operation */
 644                if (out == 1 && in == 1) {
 645                        data_direction = DMA_NONE;
 646                        data_first = 0;
 647                        data_num = 0;
 648                } else if (out == 1 && in > 1) {
 649                        data_direction = DMA_FROM_DEVICE;
 650                        data_first = out + 1;
 651                        data_num = in - 1;
 652                } else if (out > 1 && in == 1) {
 653                        data_direction = DMA_TO_DEVICE;
 654                        data_first = 1;
 655                        data_num = out - 1;
 656                } else {
 657                        vq_err(vq, "Invalid buffer layout out: %u in: %u\n",
 658                                        out, in);
 659                        break;
 660                }
 661
 662                /*
 663                 * Check for a sane resp buffer so we can report errors to
 664                 * the guest.
 665                 */
 666                if (unlikely(vq->iov[out].iov_len !=
 667                                        sizeof(struct virtio_scsi_cmd_resp))) {
 668                        vq_err(vq, "Expecting virtio_scsi_cmd_resp, got %zu"
 669                                " bytes\n", vq->iov[out].iov_len);
 670                        break;
 671                }
 672
 673                if (unlikely(vq->iov[0].iov_len != sizeof(v_req))) {
 674                        vq_err(vq, "Expecting virtio_scsi_cmd_req, got %zu"
 675                                " bytes\n", vq->iov[0].iov_len);
 676                        break;
 677                }
 678                pr_debug("Calling __copy_from_user: vq->iov[0].iov_base: %p,"
 679                        " len: %zu\n", vq->iov[0].iov_base, sizeof(v_req));
 680                ret = __copy_from_user(&v_req, vq->iov[0].iov_base,
 681                                sizeof(v_req));
 682                if (unlikely(ret)) {
 683                        vq_err(vq, "Faulted on virtio_scsi_cmd_req\n");
 684                        break;
 685                }
 686
 687                /* Extract the tpgt */
 688                target = v_req.lun[1];
 689                tv_tpg = ACCESS_ONCE(vs_tpg[target]);
 690
 691                /* Target does not exist, fail the request */
 692                if (unlikely(!tv_tpg)) {
 693                        vhost_scsi_send_bad_target(vs, vq, head, out);
 694                        continue;
 695                }
 696
 697                exp_data_len = 0;
 698                for (i = 0; i < data_num; i++)
 699                        exp_data_len += vq->iov[data_first + i].iov_len;
 700
 701                tv_cmd = vhost_scsi_allocate_cmd(tv_tpg, &v_req,
 702                                        exp_data_len, data_direction);
 703                if (IS_ERR(tv_cmd)) {
 704                        vq_err(vq, "vhost_scsi_allocate_cmd failed %ld\n",
 705                                        PTR_ERR(tv_cmd));
 706                        goto err_cmd;
 707                }
 708                pr_debug("Allocated tv_cmd: %p exp_data_len: %d, data_direction"
 709                        ": %d\n", tv_cmd, exp_data_len, data_direction);
 710
 711                tv_cmd->tvc_vhost = vs;
 712                tv_cmd->tvc_vq = vq;
 713                tv_cmd->tvc_resp = vq->iov[out].iov_base;
 714
 715                /*
 716                 * Copy in the recieved CDB descriptor into tv_cmd->tvc_cdb
 717                 * that will be used by tcm_vhost_new_cmd_map() and down into
 718                 * target_setup_cmd_from_cdb()
 719                 */
 720                memcpy(tv_cmd->tvc_cdb, v_req.cdb, TCM_VHOST_MAX_CDB_SIZE);
 721                /*
 722                 * Check that the recieved CDB size does not exceeded our
 723                 * hardcoded max for tcm_vhost
 724                 */
 725                /* TODO what if cdb was too small for varlen cdb header? */
 726                if (unlikely(scsi_command_size(tv_cmd->tvc_cdb) >
 727                                        TCM_VHOST_MAX_CDB_SIZE)) {
 728                        vq_err(vq, "Received SCSI CDB with command_size: %d that"
 729                                " exceeds SCSI_MAX_VARLEN_CDB_SIZE: %d\n",
 730                                scsi_command_size(tv_cmd->tvc_cdb),
 731                                TCM_VHOST_MAX_CDB_SIZE);
 732                        goto err_free;
 733                }
 734                tv_cmd->tvc_lun = ((v_req.lun[2] << 8) | v_req.lun[3]) & 0x3FFF;
 735
 736                pr_debug("vhost_scsi got command opcode: %#02x, lun: %d\n",
 737                        tv_cmd->tvc_cdb[0], tv_cmd->tvc_lun);
 738
 739                if (data_direction != DMA_NONE) {
 740                        ret = vhost_scsi_map_iov_to_sgl(tv_cmd,
 741                                        &vq->iov[data_first], data_num,
 742                                        data_direction == DMA_TO_DEVICE);
 743                        if (unlikely(ret)) {
 744                                vq_err(vq, "Failed to map iov to sgl\n");
 745                                goto err_free;
 746                        }
 747                }
 748
 749                /*
 750                 * Save the descriptor from vhost_get_vq_desc() to be used to
 751                 * complete the virtio-scsi request in TCM callback context via
 752                 * tcm_vhost_queue_data_in() and tcm_vhost_queue_status()
 753                 */
 754                tv_cmd->tvc_vq_desc = head;
 755                /*
 756                 * Dispatch tv_cmd descriptor for cmwq execution in process
 757                 * context provided by tcm_vhost_workqueue.  This also ensures
 758                 * tv_cmd is executed on the same kworker CPU as this vhost
 759                 * thread to gain positive L2 cache locality effects..
 760                 */
 761                INIT_WORK(&tv_cmd->work, tcm_vhost_submission_work);
 762                queue_work(tcm_vhost_workqueue, &tv_cmd->work);
 763        }
 764
 765        mutex_unlock(&vq->mutex);
 766        return;
 767
 768err_free:
 769        vhost_scsi_free_cmd(tv_cmd);
 770err_cmd:
 771        vhost_scsi_send_bad_target(vs, vq, head, out);
 772        mutex_unlock(&vq->mutex);
 773}
 774
 775static void vhost_scsi_ctl_handle_kick(struct vhost_work *work)
 776{
 777        pr_debug("%s: The handling func for control queue.\n", __func__);
 778}
 779
 780static void vhost_scsi_evt_handle_kick(struct vhost_work *work)
 781{
 782        pr_debug("%s: The handling func for event queue.\n", __func__);
 783}
 784
 785static void vhost_scsi_handle_kick(struct vhost_work *work)
 786{
 787        struct vhost_virtqueue *vq = container_of(work, struct vhost_virtqueue,
 788                                                poll.work);
 789        struct vhost_scsi *vs = container_of(vq->dev, struct vhost_scsi, dev);
 790
 791        vhost_scsi_handle_vq(vs, vq);
 792}
 793
 794static void vhost_scsi_flush_vq(struct vhost_scsi *vs, int index)
 795{
 796        vhost_poll_flush(&vs->dev.vqs[index].poll);
 797}
 798
 799static void vhost_scsi_flush(struct vhost_scsi *vs)
 800{
 801        int i;
 802
 803        for (i = 0; i < VHOST_SCSI_MAX_VQ; i++)
 804                vhost_scsi_flush_vq(vs, i);
 805        vhost_work_flush(&vs->dev, &vs->vs_completion_work);
 806}
 807
 808/*
 809 * Called from vhost_scsi_ioctl() context to walk the list of available
 810 * tcm_vhost_tpg with an active struct tcm_vhost_nexus
 811 */
 812static int vhost_scsi_set_endpoint(
 813        struct vhost_scsi *vs,
 814        struct vhost_scsi_target *t)
 815{
 816        struct tcm_vhost_tport *tv_tport;
 817        struct tcm_vhost_tpg *tv_tpg;
 818        struct tcm_vhost_tpg **vs_tpg;
 819        struct vhost_virtqueue *vq;
 820        int index, ret, i, len;
 821        bool match = false;
 822
 823        mutex_lock(&vs->dev.mutex);
 824        /* Verify that ring has been setup correctly. */
 825        for (index = 0; index < vs->dev.nvqs; ++index) {
 826                /* Verify that ring has been setup correctly. */
 827                if (!vhost_vq_access_ok(&vs->vqs[index])) {
 828                        mutex_unlock(&vs->dev.mutex);
 829                        return -EFAULT;
 830                }
 831        }
 832
 833        len = sizeof(vs_tpg[0]) * VHOST_SCSI_MAX_TARGET;
 834        vs_tpg = kzalloc(len, GFP_KERNEL);
 835        if (!vs_tpg) {
 836                mutex_unlock(&vs->dev.mutex);
 837                return -ENOMEM;
 838        }
 839        if (vs->vs_tpg)
 840                memcpy(vs_tpg, vs->vs_tpg, len);
 841
 842        mutex_lock(&tcm_vhost_mutex);
 843        list_for_each_entry(tv_tpg, &tcm_vhost_list, tv_tpg_list) {
 844                mutex_lock(&tv_tpg->tv_tpg_mutex);
 845                if (!tv_tpg->tpg_nexus) {
 846                        mutex_unlock(&tv_tpg->tv_tpg_mutex);
 847                        continue;
 848                }
 849                if (tv_tpg->tv_tpg_vhost_count != 0) {
 850                        mutex_unlock(&tv_tpg->tv_tpg_mutex);
 851                        continue;
 852                }
 853                tv_tport = tv_tpg->tport;
 854
 855                if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
 856                        if (vs->vs_tpg && vs->vs_tpg[tv_tpg->tport_tpgt]) {
 857                                mutex_unlock(&tv_tpg->tv_tpg_mutex);
 858                                mutex_unlock(&tcm_vhost_mutex);
 859                                mutex_unlock(&vs->dev.mutex);
 860                                kfree(vs_tpg);
 861                                return -EEXIST;
 862                        }
 863                        tv_tpg->tv_tpg_vhost_count++;
 864                        vs_tpg[tv_tpg->tport_tpgt] = tv_tpg;
 865                        smp_mb__after_atomic_inc();
 866                        match = true;
 867                }
 868                mutex_unlock(&tv_tpg->tv_tpg_mutex);
 869        }
 870        mutex_unlock(&tcm_vhost_mutex);
 871
 872        if (match) {
 873                memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
 874                       sizeof(vs->vs_vhost_wwpn));
 875                for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
 876                        vq = &vs->vqs[i];
 877                        /* Flushing the vhost_work acts as synchronize_rcu */
 878                        mutex_lock(&vq->mutex);
 879                        rcu_assign_pointer(vq->private_data, vs_tpg);
 880                        vhost_init_used(vq);
 881                        mutex_unlock(&vq->mutex);
 882                }
 883                ret = 0;
 884        } else {
 885                ret = -EEXIST;
 886        }
 887
 888        /*
 889         * Act as synchronize_rcu to make sure access to
 890         * old vs->vs_tpg is finished.
 891         */
 892        vhost_scsi_flush(vs);
 893        kfree(vs->vs_tpg);
 894        vs->vs_tpg = vs_tpg;
 895
 896        mutex_unlock(&vs->dev.mutex);
 897        return ret;
 898}
 899
 900static int vhost_scsi_clear_endpoint(
 901        struct vhost_scsi *vs,
 902        struct vhost_scsi_target *t)
 903{
 904        struct tcm_vhost_tport *tv_tport;
 905        struct tcm_vhost_tpg *tv_tpg;
 906        struct vhost_virtqueue *vq;
 907        bool match = false;
 908        int index, ret, i;
 909        u8 target;
 910
 911        mutex_lock(&vs->dev.mutex);
 912        /* Verify that ring has been setup correctly. */
 913        for (index = 0; index < vs->dev.nvqs; ++index) {
 914                if (!vhost_vq_access_ok(&vs->vqs[index])) {
 915                        ret = -EFAULT;
 916                        goto err_dev;
 917                }
 918        }
 919
 920        if (!vs->vs_tpg) {
 921                mutex_unlock(&vs->dev.mutex);
 922                return 0;
 923        }
 924
 925        for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
 926                target = i;
 927                tv_tpg = vs->vs_tpg[target];
 928                if (!tv_tpg)
 929                        continue;
 930
 931                mutex_lock(&tv_tpg->tv_tpg_mutex);
 932                tv_tport = tv_tpg->tport;
 933                if (!tv_tport) {
 934                        ret = -ENODEV;
 935                        goto err_tpg;
 936                }
 937
 938                if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
 939                        pr_warn("tv_tport->tport_name: %s, tv_tpg->tport_tpgt: %hu"
 940                                " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
 941                                tv_tport->tport_name, tv_tpg->tport_tpgt,
 942                                t->vhost_wwpn, t->vhost_tpgt);
 943                        ret = -EINVAL;
 944                        goto err_tpg;
 945                }
 946                tv_tpg->tv_tpg_vhost_count--;
 947                vs->vs_tpg[target] = NULL;
 948                match = true;
 949                mutex_unlock(&tv_tpg->tv_tpg_mutex);
 950        }
 951        if (match) {
 952                for (i = 0; i < VHOST_SCSI_MAX_VQ; i++) {
 953                        vq = &vs->vqs[i];
 954                        /* Flushing the vhost_work acts as synchronize_rcu */
 955                        mutex_lock(&vq->mutex);
 956                        rcu_assign_pointer(vq->private_data, NULL);
 957                        mutex_unlock(&vq->mutex);
 958                }
 959        }
 960        /*
 961         * Act as synchronize_rcu to make sure access to
 962         * old vs->vs_tpg is finished.
 963         */
 964        vhost_scsi_flush(vs);
 965        kfree(vs->vs_tpg);
 966        vs->vs_tpg = NULL;
 967        mutex_unlock(&vs->dev.mutex);
 968
 969        return 0;
 970
 971err_tpg:
 972        mutex_unlock(&tv_tpg->tv_tpg_mutex);
 973err_dev:
 974        mutex_unlock(&vs->dev.mutex);
 975        return ret;
 976}
 977
 978static int vhost_scsi_set_features(struct vhost_scsi *vs, u64 features)
 979{
 980        if (features & ~VHOST_SCSI_FEATURES)
 981                return -EOPNOTSUPP;
 982
 983        mutex_lock(&vs->dev.mutex);
 984        if ((features & (1 << VHOST_F_LOG_ALL)) &&
 985            !vhost_log_access_ok(&vs->dev)) {
 986                mutex_unlock(&vs->dev.mutex);
 987                return -EFAULT;
 988        }
 989        vs->dev.acked_features = features;
 990        smp_wmb();
 991        vhost_scsi_flush(vs);
 992        mutex_unlock(&vs->dev.mutex);
 993        return 0;
 994}
 995
 996static int vhost_scsi_open(struct inode *inode, struct file *f)
 997{
 998        struct vhost_scsi *s;
 999        int r, i;
1000
1001        s = kzalloc(sizeof(*s), GFP_KERNEL);
1002        if (!s)
1003                return -ENOMEM;
1004
1005        vhost_work_init(&s->vs_completion_work, vhost_scsi_complete_cmd_work);
1006
1007        s->vqs[VHOST_SCSI_VQ_CTL].handle_kick = vhost_scsi_ctl_handle_kick;
1008        s->vqs[VHOST_SCSI_VQ_EVT].handle_kick = vhost_scsi_evt_handle_kick;
1009        for (i = VHOST_SCSI_VQ_IO; i < VHOST_SCSI_MAX_VQ; i++)
1010                s->vqs[i].handle_kick = vhost_scsi_handle_kick;
1011        r = vhost_dev_init(&s->dev, s->vqs, VHOST_SCSI_MAX_VQ);
1012        if (r < 0) {
1013                kfree(s);
1014                return r;
1015        }
1016
1017        f->private_data = s;
1018        return 0;
1019}
1020
1021static int vhost_scsi_release(struct inode *inode, struct file *f)
1022{
1023        struct vhost_scsi *s = f->private_data;
1024        struct vhost_scsi_target t;
1025
1026        mutex_lock(&s->dev.mutex);
1027        memcpy(t.vhost_wwpn, s->vs_vhost_wwpn, sizeof(t.vhost_wwpn));
1028        mutex_unlock(&s->dev.mutex);
1029        vhost_scsi_clear_endpoint(s, &t);
1030        vhost_dev_stop(&s->dev);
1031        vhost_dev_cleanup(&s->dev, false);
1032        kfree(s);
1033        return 0;
1034}
1035
1036static long vhost_scsi_ioctl(struct file *f, unsigned int ioctl,
1037                                unsigned long arg)
1038{
1039        struct vhost_scsi *vs = f->private_data;
1040        struct vhost_scsi_target backend;
1041        void __user *argp = (void __user *)arg;
1042        u64 __user *featurep = argp;
1043        u64 features;
1044        int r, abi_version = VHOST_SCSI_ABI_VERSION;
1045
1046        switch (ioctl) {
1047        case VHOST_SCSI_SET_ENDPOINT:
1048                if (copy_from_user(&backend, argp, sizeof backend))
1049                        return -EFAULT;
1050                if (backend.reserved != 0)
1051                        return -EOPNOTSUPP;
1052
1053                return vhost_scsi_set_endpoint(vs, &backend);
1054        case VHOST_SCSI_CLEAR_ENDPOINT:
1055                if (copy_from_user(&backend, argp, sizeof backend))
1056                        return -EFAULT;
1057                if (backend.reserved != 0)
1058                        return -EOPNOTSUPP;
1059
1060                return vhost_scsi_clear_endpoint(vs, &backend);
1061        case VHOST_SCSI_GET_ABI_VERSION:
1062                if (copy_to_user(argp, &abi_version, sizeof abi_version))
1063                        return -EFAULT;
1064                return 0;
1065        case VHOST_GET_FEATURES:
1066                features = VHOST_SCSI_FEATURES;
1067                if (copy_to_user(featurep, &features, sizeof features))
1068                        return -EFAULT;
1069                return 0;
1070        case VHOST_SET_FEATURES:
1071                if (copy_from_user(&features, featurep, sizeof features))
1072                        return -EFAULT;
1073                return vhost_scsi_set_features(vs, features);
1074        default:
1075                mutex_lock(&vs->dev.mutex);
1076                r = vhost_dev_ioctl(&vs->dev, ioctl, argp);
1077                /* TODO: flush backend after dev ioctl. */
1078                if (r == -ENOIOCTLCMD)
1079                        r = vhost_vring_ioctl(&vs->dev, ioctl, argp);
1080                mutex_unlock(&vs->dev.mutex);
1081                return r;
1082        }
1083}
1084
1085#ifdef CONFIG_COMPAT
1086static long vhost_scsi_compat_ioctl(struct file *f, unsigned int ioctl,
1087                                unsigned long arg)
1088{
1089        return vhost_scsi_ioctl(f, ioctl, (unsigned long)compat_ptr(arg));
1090}
1091#endif
1092
1093static const struct file_operations vhost_scsi_fops = {
1094        .owner          = THIS_MODULE,
1095        .release        = vhost_scsi_release,
1096        .unlocked_ioctl = vhost_scsi_ioctl,
1097#ifdef CONFIG_COMPAT
1098        .compat_ioctl   = vhost_scsi_compat_ioctl,
1099#endif
1100        .open           = vhost_scsi_open,
1101        .llseek         = noop_llseek,
1102};
1103
1104static struct miscdevice vhost_scsi_misc = {
1105        MISC_DYNAMIC_MINOR,
1106        "vhost-scsi",
1107        &vhost_scsi_fops,
1108};
1109
1110static int __init vhost_scsi_register(void)
1111{
1112        return misc_register(&vhost_scsi_misc);
1113}
1114
1115static int vhost_scsi_deregister(void)
1116{
1117        return misc_deregister(&vhost_scsi_misc);
1118}
1119
1120static char *tcm_vhost_dump_proto_id(struct tcm_vhost_tport *tport)
1121{
1122        switch (tport->tport_proto_id) {
1123        case SCSI_PROTOCOL_SAS:
1124                return "SAS";
1125        case SCSI_PROTOCOL_FCP:
1126                return "FCP";
1127        case SCSI_PROTOCOL_ISCSI:
1128                return "iSCSI";
1129        default:
1130                break;
1131        }
1132
1133        return "Unknown";
1134}
1135
1136static int tcm_vhost_port_link(struct se_portal_group *se_tpg,
1137        struct se_lun *lun)
1138{
1139        struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg,
1140                                struct tcm_vhost_tpg, se_tpg);
1141
1142        mutex_lock(&tv_tpg->tv_tpg_mutex);
1143        tv_tpg->tv_tpg_port_count++;
1144        mutex_unlock(&tv_tpg->tv_tpg_mutex);
1145
1146        return 0;
1147}
1148
1149static void tcm_vhost_port_unlink(struct se_portal_group *se_tpg,
1150        struct se_lun *se_lun)
1151{
1152        struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg,
1153                                struct tcm_vhost_tpg, se_tpg);
1154
1155        mutex_lock(&tv_tpg->tv_tpg_mutex);
1156        tv_tpg->tv_tpg_port_count--;
1157        mutex_unlock(&tv_tpg->tv_tpg_mutex);
1158}
1159
1160static struct se_node_acl *tcm_vhost_make_nodeacl(
1161        struct se_portal_group *se_tpg,
1162        struct config_group *group,
1163        const char *name)
1164{
1165        struct se_node_acl *se_nacl, *se_nacl_new;
1166        struct tcm_vhost_nacl *nacl;
1167        u64 wwpn = 0;
1168        u32 nexus_depth;
1169
1170        /* tcm_vhost_parse_wwn(name, &wwpn, 1) < 0)
1171                return ERR_PTR(-EINVAL); */
1172        se_nacl_new = tcm_vhost_alloc_fabric_acl(se_tpg);
1173        if (!se_nacl_new)
1174                return ERR_PTR(-ENOMEM);
1175
1176        nexus_depth = 1;
1177        /*
1178         * se_nacl_new may be released by core_tpg_add_initiator_node_acl()
1179         * when converting a NodeACL from demo mode -> explict
1180         */
1181        se_nacl = core_tpg_add_initiator_node_acl(se_tpg, se_nacl_new,
1182                                name, nexus_depth);
1183        if (IS_ERR(se_nacl)) {
1184                tcm_vhost_release_fabric_acl(se_tpg, se_nacl_new);
1185                return se_nacl;
1186        }
1187        /*
1188         * Locate our struct tcm_vhost_nacl and set the FC Nport WWPN
1189         */
1190        nacl = container_of(se_nacl, struct tcm_vhost_nacl, se_node_acl);
1191        nacl->iport_wwpn = wwpn;
1192
1193        return se_nacl;
1194}
1195
1196static void tcm_vhost_drop_nodeacl(struct se_node_acl *se_acl)
1197{
1198        struct tcm_vhost_nacl *nacl = container_of(se_acl,
1199                                struct tcm_vhost_nacl, se_node_acl);
1200        core_tpg_del_initiator_node_acl(se_acl->se_tpg, se_acl, 1);
1201        kfree(nacl);
1202}
1203
1204static int tcm_vhost_make_nexus(struct tcm_vhost_tpg *tv_tpg,
1205        const char *name)
1206{
1207        struct se_portal_group *se_tpg;
1208        struct tcm_vhost_nexus *tv_nexus;
1209
1210        mutex_lock(&tv_tpg->tv_tpg_mutex);
1211        if (tv_tpg->tpg_nexus) {
1212                mutex_unlock(&tv_tpg->tv_tpg_mutex);
1213                pr_debug("tv_tpg->tpg_nexus already exists\n");
1214                return -EEXIST;
1215        }
1216        se_tpg = &tv_tpg->se_tpg;
1217
1218        tv_nexus = kzalloc(sizeof(struct tcm_vhost_nexus), GFP_KERNEL);
1219        if (!tv_nexus) {
1220                mutex_unlock(&tv_tpg->tv_tpg_mutex);
1221                pr_err("Unable to allocate struct tcm_vhost_nexus\n");
1222                return -ENOMEM;
1223        }
1224        /*
1225         *  Initialize the struct se_session pointer
1226         */
1227        tv_nexus->tvn_se_sess = transport_init_session();
1228        if (IS_ERR(tv_nexus->tvn_se_sess)) {
1229                mutex_unlock(&tv_tpg->tv_tpg_mutex);
1230                kfree(tv_nexus);
1231                return -ENOMEM;
1232        }
1233        /*
1234         * Since we are running in 'demo mode' this call with generate a
1235         * struct se_node_acl for the tcm_vhost struct se_portal_group with
1236         * the SCSI Initiator port name of the passed configfs group 'name'.
1237         */
1238        tv_nexus->tvn_se_sess->se_node_acl = core_tpg_check_initiator_node_acl(
1239                                se_tpg, (unsigned char *)name);
1240        if (!tv_nexus->tvn_se_sess->se_node_acl) {
1241                mutex_unlock(&tv_tpg->tv_tpg_mutex);
1242                pr_debug("core_tpg_check_initiator_node_acl() failed"
1243                                " for %s\n", name);
1244                transport_free_session(tv_nexus->tvn_se_sess);
1245                kfree(tv_nexus);
1246                return -ENOMEM;
1247        }
1248        /*
1249         * Now register the TCM vhost virtual I_T Nexus as active with the
1250         * call to __transport_register_session()
1251         */
1252        __transport_register_session(se_tpg, tv_nexus->tvn_se_sess->se_node_acl,
1253                        tv_nexus->tvn_se_sess, tv_nexus);
1254        tv_tpg->tpg_nexus = tv_nexus;
1255
1256        mutex_unlock(&tv_tpg->tv_tpg_mutex);
1257        return 0;
1258}
1259
1260static int tcm_vhost_drop_nexus(struct tcm_vhost_tpg *tpg)
1261{
1262        struct se_session *se_sess;
1263        struct tcm_vhost_nexus *tv_nexus;
1264
1265        mutex_lock(&tpg->tv_tpg_mutex);
1266        tv_nexus = tpg->tpg_nexus;
1267        if (!tv_nexus) {
1268                mutex_unlock(&tpg->tv_tpg_mutex);
1269                return -ENODEV;
1270        }
1271
1272        se_sess = tv_nexus->tvn_se_sess;
1273        if (!se_sess) {
1274                mutex_unlock(&tpg->tv_tpg_mutex);
1275                return -ENODEV;
1276        }
1277
1278        if (tpg->tv_tpg_port_count != 0) {
1279                mutex_unlock(&tpg->tv_tpg_mutex);
1280                pr_err("Unable to remove TCM_vhost I_T Nexus with"
1281                        " active TPG port count: %d\n",
1282                        tpg->tv_tpg_port_count);
1283                return -EBUSY;
1284        }
1285
1286        if (tpg->tv_tpg_vhost_count != 0) {
1287                mutex_unlock(&tpg->tv_tpg_mutex);
1288                pr_err("Unable to remove TCM_vhost I_T Nexus with"
1289                        " active TPG vhost count: %d\n",
1290                        tpg->tv_tpg_vhost_count);
1291                return -EBUSY;
1292        }
1293
1294        pr_debug("TCM_vhost_ConfigFS: Removing I_T Nexus to emulated"
1295                " %s Initiator Port: %s\n", tcm_vhost_dump_proto_id(tpg->tport),
1296                tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1297        /*
1298         * Release the SCSI I_T Nexus to the emulated vhost Target Port
1299         */
1300        transport_deregister_session(tv_nexus->tvn_se_sess);
1301        tpg->tpg_nexus = NULL;
1302        mutex_unlock(&tpg->tv_tpg_mutex);
1303
1304        kfree(tv_nexus);
1305        return 0;
1306}
1307
1308static ssize_t tcm_vhost_tpg_show_nexus(struct se_portal_group *se_tpg,
1309        char *page)
1310{
1311        struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg,
1312                                struct tcm_vhost_tpg, se_tpg);
1313        struct tcm_vhost_nexus *tv_nexus;
1314        ssize_t ret;
1315
1316        mutex_lock(&tv_tpg->tv_tpg_mutex);
1317        tv_nexus = tv_tpg->tpg_nexus;
1318        if (!tv_nexus) {
1319                mutex_unlock(&tv_tpg->tv_tpg_mutex);
1320                return -ENODEV;
1321        }
1322        ret = snprintf(page, PAGE_SIZE, "%s\n",
1323                        tv_nexus->tvn_se_sess->se_node_acl->initiatorname);
1324        mutex_unlock(&tv_tpg->tv_tpg_mutex);
1325
1326        return ret;
1327}
1328
1329static ssize_t tcm_vhost_tpg_store_nexus(struct se_portal_group *se_tpg,
1330        const char *page,
1331        size_t count)
1332{
1333        struct tcm_vhost_tpg *tv_tpg = container_of(se_tpg,
1334                                struct tcm_vhost_tpg, se_tpg);
1335        struct tcm_vhost_tport *tport_wwn = tv_tpg->tport;
1336        unsigned char i_port[TCM_VHOST_NAMELEN], *ptr, *port_ptr;
1337        int ret;
1338        /*
1339         * Shutdown the active I_T nexus if 'NULL' is passed..
1340         */
1341        if (!strncmp(page, "NULL", 4)) {
1342                ret = tcm_vhost_drop_nexus(tv_tpg);
1343                return (!ret) ? count : ret;
1344        }
1345        /*
1346         * Otherwise make sure the passed virtual Initiator port WWN matches
1347         * the fabric protocol_id set in tcm_vhost_make_tport(), and call
1348         * tcm_vhost_make_nexus().
1349         */
1350        if (strlen(page) >= TCM_VHOST_NAMELEN) {
1351                pr_err("Emulated NAA Sas Address: %s, exceeds"
1352                                " max: %d\n", page, TCM_VHOST_NAMELEN);
1353                return -EINVAL;
1354        }
1355        snprintf(&i_port[0], TCM_VHOST_NAMELEN, "%s", page);
1356
1357        ptr = strstr(i_port, "naa.");
1358        if (ptr) {
1359                if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) {
1360                        pr_err("Passed SAS Initiator Port %s does not"
1361                                " match target port protoid: %s\n", i_port,
1362                                tcm_vhost_dump_proto_id(tport_wwn));
1363                        return -EINVAL;
1364                }
1365                port_ptr = &i_port[0];
1366                goto check_newline;
1367        }
1368        ptr = strstr(i_port, "fc.");
1369        if (ptr) {
1370                if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) {
1371                        pr_err("Passed FCP Initiator Port %s does not"
1372                                " match target port protoid: %s\n", i_port,
1373                                tcm_vhost_dump_proto_id(tport_wwn));
1374                        return -EINVAL;
1375                }
1376                port_ptr = &i_port[3]; /* Skip over "fc." */
1377                goto check_newline;
1378        }
1379        ptr = strstr(i_port, "iqn.");
1380        if (ptr) {
1381                if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) {
1382                        pr_err("Passed iSCSI Initiator Port %s does not"
1383                                " match target port protoid: %s\n", i_port,
1384                                tcm_vhost_dump_proto_id(tport_wwn));
1385                        return -EINVAL;
1386                }
1387                port_ptr = &i_port[0];
1388                goto check_newline;
1389        }
1390        pr_err("Unable to locate prefix for emulated Initiator Port:"
1391                        " %s\n", i_port);
1392        return -EINVAL;
1393        /*
1394         * Clear any trailing newline for the NAA WWN
1395         */
1396check_newline:
1397        if (i_port[strlen(i_port)-1] == '\n')
1398                i_port[strlen(i_port)-1] = '\0';
1399
1400        ret = tcm_vhost_make_nexus(tv_tpg, port_ptr);
1401        if (ret < 0)
1402                return ret;
1403
1404        return count;
1405}
1406
1407TF_TPG_BASE_ATTR(tcm_vhost, nexus, S_IRUGO | S_IWUSR);
1408
1409static struct configfs_attribute *tcm_vhost_tpg_attrs[] = {
1410        &tcm_vhost_tpg_nexus.attr,
1411        NULL,
1412};
1413
1414static struct se_portal_group *tcm_vhost_make_tpg(struct se_wwn *wwn,
1415        struct config_group *group,
1416        const char *name)
1417{
1418        struct tcm_vhost_tport *tport = container_of(wwn,
1419                        struct tcm_vhost_tport, tport_wwn);
1420
1421        struct tcm_vhost_tpg *tpg;
1422        unsigned long tpgt;
1423        int ret;
1424
1425        if (strstr(name, "tpgt_") != name)
1426                return ERR_PTR(-EINVAL);
1427        if (kstrtoul(name + 5, 10, &tpgt) || tpgt > UINT_MAX)
1428                return ERR_PTR(-EINVAL);
1429
1430        tpg = kzalloc(sizeof(struct tcm_vhost_tpg), GFP_KERNEL);
1431        if (!tpg) {
1432                pr_err("Unable to allocate struct tcm_vhost_tpg");
1433                return ERR_PTR(-ENOMEM);
1434        }
1435        mutex_init(&tpg->tv_tpg_mutex);
1436        INIT_LIST_HEAD(&tpg->tv_tpg_list);
1437        tpg->tport = tport;
1438        tpg->tport_tpgt = tpgt;
1439
1440        ret = core_tpg_register(&tcm_vhost_fabric_configfs->tf_ops, wwn,
1441                                &tpg->se_tpg, tpg, TRANSPORT_TPG_TYPE_NORMAL);
1442        if (ret < 0) {
1443                kfree(tpg);
1444                return NULL;
1445        }
1446        mutex_lock(&tcm_vhost_mutex);
1447        list_add_tail(&tpg->tv_tpg_list, &tcm_vhost_list);
1448        mutex_unlock(&tcm_vhost_mutex);
1449
1450        return &tpg->se_tpg;
1451}
1452
1453static void tcm_vhost_drop_tpg(struct se_portal_group *se_tpg)
1454{
1455        struct tcm_vhost_tpg *tpg = container_of(se_tpg,
1456                                struct tcm_vhost_tpg, se_tpg);
1457
1458        mutex_lock(&tcm_vhost_mutex);
1459        list_del(&tpg->tv_tpg_list);
1460        mutex_unlock(&tcm_vhost_mutex);
1461        /*
1462         * Release the virtual I_T Nexus for this vhost TPG
1463         */
1464        tcm_vhost_drop_nexus(tpg);
1465        /*
1466         * Deregister the se_tpg from TCM..
1467         */
1468        core_tpg_deregister(se_tpg);
1469        kfree(tpg);
1470}
1471
1472static struct se_wwn *tcm_vhost_make_tport(struct target_fabric_configfs *tf,
1473        struct config_group *group,
1474        const char *name)
1475{
1476        struct tcm_vhost_tport *tport;
1477        char *ptr;
1478        u64 wwpn = 0;
1479        int off = 0;
1480
1481        /* if (tcm_vhost_parse_wwn(name, &wwpn, 1) < 0)
1482                return ERR_PTR(-EINVAL); */
1483
1484        tport = kzalloc(sizeof(struct tcm_vhost_tport), GFP_KERNEL);
1485        if (!tport) {
1486                pr_err("Unable to allocate struct tcm_vhost_tport");
1487                return ERR_PTR(-ENOMEM);
1488        }
1489        tport->tport_wwpn = wwpn;
1490        /*
1491         * Determine the emulated Protocol Identifier and Target Port Name
1492         * based on the incoming configfs directory name.
1493         */
1494        ptr = strstr(name, "naa.");
1495        if (ptr) {
1496                tport->tport_proto_id = SCSI_PROTOCOL_SAS;
1497                goto check_len;
1498        }
1499        ptr = strstr(name, "fc.");
1500        if (ptr) {
1501                tport->tport_proto_id = SCSI_PROTOCOL_FCP;
1502                off = 3; /* Skip over "fc." */
1503                goto check_len;
1504        }
1505        ptr = strstr(name, "iqn.");
1506        if (ptr) {
1507                tport->tport_proto_id = SCSI_PROTOCOL_ISCSI;
1508                goto check_len;
1509        }
1510
1511        pr_err("Unable to locate prefix for emulated Target Port:"
1512                        " %s\n", name);
1513        kfree(tport);
1514        return ERR_PTR(-EINVAL);
1515
1516check_len:
1517        if (strlen(name) >= TCM_VHOST_NAMELEN) {
1518                pr_err("Emulated %s Address: %s, exceeds"
1519                        " max: %d\n", name, tcm_vhost_dump_proto_id(tport),
1520                        TCM_VHOST_NAMELEN);
1521                kfree(tport);
1522                return ERR_PTR(-EINVAL);
1523        }
1524        snprintf(&tport->tport_name[0], TCM_VHOST_NAMELEN, "%s", &name[off]);
1525
1526        pr_debug("TCM_VHost_ConfigFS: Allocated emulated Target"
1527                " %s Address: %s\n", tcm_vhost_dump_proto_id(tport), name);
1528
1529        return &tport->tport_wwn;
1530}
1531
1532static void tcm_vhost_drop_tport(struct se_wwn *wwn)
1533{
1534        struct tcm_vhost_tport *tport = container_of(wwn,
1535                                struct tcm_vhost_tport, tport_wwn);
1536
1537        pr_debug("TCM_VHost_ConfigFS: Deallocating emulated Target"
1538                " %s Address: %s\n", tcm_vhost_dump_proto_id(tport),
1539                tport->tport_name);
1540
1541        kfree(tport);
1542}
1543
1544static ssize_t tcm_vhost_wwn_show_attr_version(
1545        struct target_fabric_configfs *tf,
1546        char *page)
1547{
1548        return sprintf(page, "TCM_VHOST fabric module %s on %s/%s"
1549                "on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname,
1550                utsname()->machine);
1551}
1552
1553TF_WWN_ATTR_RO(tcm_vhost, version);
1554
1555static struct configfs_attribute *tcm_vhost_wwn_attrs[] = {
1556        &tcm_vhost_wwn_version.attr,
1557        NULL,
1558};
1559
1560static struct target_core_fabric_ops tcm_vhost_ops = {
1561        .get_fabric_name                = tcm_vhost_get_fabric_name,
1562        .get_fabric_proto_ident         = tcm_vhost_get_fabric_proto_ident,
1563        .tpg_get_wwn                    = tcm_vhost_get_fabric_wwn,
1564        .tpg_get_tag                    = tcm_vhost_get_tag,
1565        .tpg_get_default_depth          = tcm_vhost_get_default_depth,
1566        .tpg_get_pr_transport_id        = tcm_vhost_get_pr_transport_id,
1567        .tpg_get_pr_transport_id_len    = tcm_vhost_get_pr_transport_id_len,
1568        .tpg_parse_pr_out_transport_id  = tcm_vhost_parse_pr_out_transport_id,
1569        .tpg_check_demo_mode            = tcm_vhost_check_true,
1570        .tpg_check_demo_mode_cache      = tcm_vhost_check_true,
1571        .tpg_check_demo_mode_write_protect = tcm_vhost_check_false,
1572        .tpg_check_prod_mode_write_protect = tcm_vhost_check_false,
1573        .tpg_alloc_fabric_acl           = tcm_vhost_alloc_fabric_acl,
1574        .tpg_release_fabric_acl         = tcm_vhost_release_fabric_acl,
1575        .tpg_get_inst_index             = tcm_vhost_tpg_get_inst_index,
1576        .release_cmd                    = tcm_vhost_release_cmd,
1577        .shutdown_session               = tcm_vhost_shutdown_session,
1578        .close_session                  = tcm_vhost_close_session,
1579        .sess_get_index                 = tcm_vhost_sess_get_index,
1580        .sess_get_initiator_sid         = NULL,
1581        .write_pending                  = tcm_vhost_write_pending,
1582        .write_pending_status           = tcm_vhost_write_pending_status,
1583        .set_default_node_attributes    = tcm_vhost_set_default_node_attrs,
1584        .get_task_tag                   = tcm_vhost_get_task_tag,
1585        .get_cmd_state                  = tcm_vhost_get_cmd_state,
1586        .queue_data_in                  = tcm_vhost_queue_data_in,
1587        .queue_status                   = tcm_vhost_queue_status,
1588        .queue_tm_rsp                   = tcm_vhost_queue_tm_rsp,
1589        /*
1590         * Setup callers for generic logic in target_core_fabric_configfs.c
1591         */
1592        .fabric_make_wwn                = tcm_vhost_make_tport,
1593        .fabric_drop_wwn                = tcm_vhost_drop_tport,
1594        .fabric_make_tpg                = tcm_vhost_make_tpg,
1595        .fabric_drop_tpg                = tcm_vhost_drop_tpg,
1596        .fabric_post_link               = tcm_vhost_port_link,
1597        .fabric_pre_unlink              = tcm_vhost_port_unlink,
1598        .fabric_make_np                 = NULL,
1599        .fabric_drop_np                 = NULL,
1600        .fabric_make_nodeacl            = tcm_vhost_make_nodeacl,
1601        .fabric_drop_nodeacl            = tcm_vhost_drop_nodeacl,
1602};
1603
1604static int tcm_vhost_register_configfs(void)
1605{
1606        struct target_fabric_configfs *fabric;
1607        int ret;
1608
1609        pr_debug("TCM_VHOST fabric module %s on %s/%s"
1610                " on "UTS_RELEASE"\n", TCM_VHOST_VERSION, utsname()->sysname,
1611                utsname()->machine);
1612        /*
1613         * Register the top level struct config_item_type with TCM core
1614         */
1615        fabric = target_fabric_configfs_init(THIS_MODULE, "vhost");
1616        if (IS_ERR(fabric)) {
1617                pr_err("target_fabric_configfs_init() failed\n");
1618                return PTR_ERR(fabric);
1619        }
1620        /*
1621         * Setup fabric->tf_ops from our local tcm_vhost_ops
1622         */
1623        fabric->tf_ops = tcm_vhost_ops;
1624        /*
1625         * Setup default attribute lists for various fabric->tf_cit_tmpl
1626         */
1627        TF_CIT_TMPL(fabric)->tfc_wwn_cit.ct_attrs = tcm_vhost_wwn_attrs;
1628        TF_CIT_TMPL(fabric)->tfc_tpg_base_cit.ct_attrs = tcm_vhost_tpg_attrs;
1629        TF_CIT_TMPL(fabric)->tfc_tpg_attrib_cit.ct_attrs = NULL;
1630        TF_CIT_TMPL(fabric)->tfc_tpg_param_cit.ct_attrs = NULL;
1631        TF_CIT_TMPL(fabric)->tfc_tpg_np_base_cit.ct_attrs = NULL;
1632        TF_CIT_TMPL(fabric)->tfc_tpg_nacl_base_cit.ct_attrs = NULL;
1633        TF_CIT_TMPL(fabric)->tfc_tpg_nacl_attrib_cit.ct_attrs = NULL;
1634        TF_CIT_TMPL(fabric)->tfc_tpg_nacl_auth_cit.ct_attrs = NULL;
1635        TF_CIT_TMPL(fabric)->tfc_tpg_nacl_param_cit.ct_attrs = NULL;
1636        /*
1637         * Register the fabric for use within TCM
1638         */
1639        ret = target_fabric_configfs_register(fabric);
1640        if (ret < 0) {
1641                pr_err("target_fabric_configfs_register() failed"
1642                                " for TCM_VHOST\n");
1643                return ret;
1644        }
1645        /*
1646         * Setup our local pointer to *fabric
1647         */
1648        tcm_vhost_fabric_configfs = fabric;
1649        pr_debug("TCM_VHOST[0] - Set fabric -> tcm_vhost_fabric_configfs\n");
1650        return 0;
1651};
1652
1653static void tcm_vhost_deregister_configfs(void)
1654{
1655        if (!tcm_vhost_fabric_configfs)
1656                return;
1657
1658        target_fabric_configfs_deregister(tcm_vhost_fabric_configfs);
1659        tcm_vhost_fabric_configfs = NULL;
1660        pr_debug("TCM_VHOST[0] - Cleared tcm_vhost_fabric_configfs\n");
1661};
1662
1663static int __init tcm_vhost_init(void)
1664{
1665        int ret = -ENOMEM;
1666        /*
1667         * Use our own dedicated workqueue for submitting I/O into
1668         * target core to avoid contention within system_wq.
1669         */
1670        tcm_vhost_workqueue = alloc_workqueue("tcm_vhost", 0, 0);
1671        if (!tcm_vhost_workqueue)
1672                goto out;
1673
1674        ret = vhost_scsi_register();
1675        if (ret < 0)
1676                goto out_destroy_workqueue;
1677
1678        ret = tcm_vhost_register_configfs();
1679        if (ret < 0)
1680                goto out_vhost_scsi_deregister;
1681
1682        return 0;
1683
1684out_vhost_scsi_deregister:
1685        vhost_scsi_deregister();
1686out_destroy_workqueue:
1687        destroy_workqueue(tcm_vhost_workqueue);
1688out:
1689        return ret;
1690};
1691
1692static void tcm_vhost_exit(void)
1693{
1694        tcm_vhost_deregister_configfs();
1695        vhost_scsi_deregister();
1696        destroy_workqueue(tcm_vhost_workqueue);
1697};
1698
1699MODULE_DESCRIPTION("TCM_VHOST series fabric driver");
1700MODULE_LICENSE("GPL");
1701module_init(tcm_vhost_init);
1702module_exit(tcm_vhost_exit);
1703
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