1/* 2 * Xen SCSI backend driver 3 * 4 * Copyright (c) 2008, FUJITSU Limited 5 * 6 * Based on the blkback driver code. 7 * Adaption to kernel taget core infrastructure taken from vhost/scsi.c 8 * 9 * This program is free software; you can redistribute it and/or 10 * modify it under the terms of the GNU General Public License version 2 11 * as published by the Free Software Foundation; or, when distributed 12 * separately from the Linux kernel or incorporated into other 13 * software packages, subject to the following license: 14 * 15 * Permission is hereby granted, free of charge, to any person obtaining a copy 16 * of this source file (the "Software"), to deal in the Software without 17 * restriction, including without limitation the rights to use, copy, modify, 18 * merge, publish, distribute, sublicense, and/or sell copies of the Software, 19 * and to permit persons to whom the Software is furnished to do so, subject to 20 * the following conditions: 21 * 22 * The above copyright notice and this permission notice shall be included in 23 * all copies or substantial portions of the Software. 24 * 25 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 26 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 27 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 28 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 29 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 30 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS 31 * IN THE SOFTWARE. 32 */ 33 34#define pr_fmt(fmt) "xen-pvscsi: " fmt 35 36#include <stdarg.h> 37 38#include <linux/module.h> 39#include <linux/utsname.h> 40#include <linux/interrupt.h> 41#include <linux/slab.h> 42#include <linux/wait.h> 43#include <linux/sched.h> 44#include <linux/list.h> 45#include <linux/gfp.h> 46#include <linux/delay.h> 47#include <linux/spinlock.h> 48#include <linux/configfs.h> 49 50#include <generated/utsrelease.h> 51 52#include <scsi/scsi_host.h> /* SG_ALL */ 53 54#include <target/target_core_base.h> 55#include <target/target_core_fabric.h> 56 57#include <asm/hypervisor.h> 58 59#include <xen/xen.h> 60#include <xen/balloon.h> 61#include <xen/events.h> 62#include <xen/xenbus.h> 63#include <xen/grant_table.h> 64#include <xen/page.h> 65 66#include <xen/interface/grant_table.h> 67#include <xen/interface/io/vscsiif.h> 68 69#define VSCSI_VERSION "v0.1" 70#define VSCSI_NAMELEN 32 71 72struct ids_tuple { 73 unsigned int hst; /* host */ 74 unsigned int chn; /* channel */ 75 unsigned int tgt; /* target */ 76 unsigned int lun; /* LUN */ 77}; 78 79struct v2p_entry { 80 struct ids_tuple v; /* translate from */ 81 struct scsiback_tpg *tpg; /* translate to */ 82 unsigned int lun; 83 struct kref kref; 84 struct list_head l; 85}; 86 87struct vscsibk_info { 88 struct xenbus_device *dev; 89 90 domid_t domid; 91 unsigned int irq; 92 93 struct vscsiif_back_ring ring; 94 int ring_error; 95 96 spinlock_t ring_lock; 97 atomic_t nr_unreplied_reqs; 98 99 spinlock_t v2p_lock; 100 struct list_head v2p_entry_lists; 101 102 wait_queue_head_t waiting_to_free; 103}; 104 105/* theoretical maximum of grants for one request */ 106#define VSCSI_MAX_GRANTS (SG_ALL + VSCSIIF_SG_TABLESIZE) 107 108/* 109 * VSCSI_GRANT_BATCH is the maximum number of grants to be processed in one 110 * call to map/unmap grants. Don't choose it too large, as there are arrays 111 * with VSCSI_GRANT_BATCH elements allocated on the stack. 112 */ 113#define VSCSI_GRANT_BATCH 16 114 115struct vscsibk_pend { 116 uint16_t rqid; 117 118 uint8_t cmnd[VSCSIIF_MAX_COMMAND_SIZE]; 119 uint8_t cmd_len; 120 121 uint8_t sc_data_direction; 122 uint16_t n_sg; /* real length of SG list */ 123 uint16_t n_grants; /* SG pages and potentially SG list */ 124 uint32_t data_len; 125 uint32_t result; 126 127 struct vscsibk_info *info; 128 struct v2p_entry *v2p; 129 struct scatterlist *sgl; 130 131 uint8_t sense_buffer[VSCSIIF_SENSE_BUFFERSIZE]; 132 133 grant_handle_t grant_handles[VSCSI_MAX_GRANTS]; 134 struct page *pages[VSCSI_MAX_GRANTS]; 135 136 struct se_cmd se_cmd; 137}; 138 139struct scsiback_tmr { 140 atomic_t tmr_complete; 141 wait_queue_head_t tmr_wait; 142}; 143 144struct scsiback_nexus { 145 /* Pointer to TCM session for I_T Nexus */ 146 struct se_session *tvn_se_sess; 147}; 148 149struct scsiback_tport { 150 /* SCSI protocol the tport is providing */ 151 u8 tport_proto_id; 152 /* Binary World Wide unique Port Name for pvscsi Target port */ 153 u64 tport_wwpn; 154 /* ASCII formatted WWPN for pvscsi Target port */ 155 char tport_name[VSCSI_NAMELEN]; 156 /* Returned by scsiback_make_tport() */ 157 struct se_wwn tport_wwn; 158}; 159 160struct scsiback_tpg { 161 /* scsiback port target portal group tag for TCM */ 162 u16 tport_tpgt; 163 /* track number of TPG Port/Lun Links wrt explicit I_T Nexus shutdown */ 164 int tv_tpg_port_count; 165 /* xen-pvscsi references to tpg_nexus, protected by tv_tpg_mutex */ 166 int tv_tpg_fe_count; 167 /* list for scsiback_list */ 168 struct list_head tv_tpg_list; 169 /* Used to protect access for tpg_nexus */ 170 struct mutex tv_tpg_mutex; 171 /* Pointer to the TCM pvscsi I_T Nexus for this TPG endpoint */ 172 struct scsiback_nexus *tpg_nexus; 173 /* Pointer back to scsiback_tport */ 174 struct scsiback_tport *tport; 175 /* Returned by scsiback_make_tpg() */ 176 struct se_portal_group se_tpg; 177 /* alias used in xenstore */ 178 char param_alias[VSCSI_NAMELEN]; 179 /* list of info structures related to this target portal group */ 180 struct list_head info_list; 181}; 182 183#define SCSIBACK_INVALID_HANDLE (~0) 184 185static bool log_print_stat; 186module_param(log_print_stat, bool, 0644); 187 188static int scsiback_max_buffer_pages = 1024; 189module_param_named(max_buffer_pages, scsiback_max_buffer_pages, int, 0644); 190MODULE_PARM_DESC(max_buffer_pages, 191"Maximum number of free pages to keep in backend buffer"); 192 193static struct kmem_cache *scsiback_cachep; 194static DEFINE_SPINLOCK(free_pages_lock); 195static int free_pages_num; 196static LIST_HEAD(scsiback_free_pages); 197 198/* Global spinlock to protect scsiback TPG list */ 199static DEFINE_MUTEX(scsiback_mutex); 200static LIST_HEAD(scsiback_list); 201 202static void scsiback_get(struct vscsibk_info *info) 203{ 204 atomic_inc(&info->nr_unreplied_reqs); 205} 206 207static void scsiback_put(struct vscsibk_info *info) 208{ 209 if (atomic_dec_and_test(&info->nr_unreplied_reqs)) 210 wake_up(&info->waiting_to_free); 211} 212 213static void put_free_pages(struct page **page, int num) 214{ 215 unsigned long flags; 216 int i = free_pages_num + num, n = num; 217 218 if (num == 0) 219 return; 220 if (i > scsiback_max_buffer_pages) { 221 n = min(num, i - scsiback_max_buffer_pages); 222 gnttab_free_pages(n, page + num - n); 223 n = num - n; 224 } 225 spin_lock_irqsave(&free_pages_lock, flags); 226 for (i = 0; i < n; i++) 227 list_add(&page[i]->lru, &scsiback_free_pages); 228 free_pages_num += n; 229 spin_unlock_irqrestore(&free_pages_lock, flags); 230} 231 232static int get_free_page(struct page **page) 233{ 234 unsigned long flags; 235 236 spin_lock_irqsave(&free_pages_lock, flags); 237 if (list_empty(&scsiback_free_pages)) { 238 spin_unlock_irqrestore(&free_pages_lock, flags); 239 return gnttab_alloc_pages(1, page); 240 } 241 page[0] = list_first_entry(&scsiback_free_pages, struct page, lru); 242 list_del(&page[0]->lru); 243 free_pages_num--; 244 spin_unlock_irqrestore(&free_pages_lock, flags); 245 return 0; 246} 247 248static unsigned long vaddr_page(struct page *page) 249{ 250 unsigned long pfn = page_to_pfn(page); 251 252 return (unsigned long)pfn_to_kaddr(pfn); 253} 254 255static unsigned long vaddr(struct vscsibk_pend *req, int seg) 256{ 257 return vaddr_page(req->pages[seg]); 258} 259 260static void scsiback_print_status(char *sense_buffer, int errors, 261 struct vscsibk_pend *pending_req) 262{ 263 struct scsiback_tpg *tpg = pending_req->v2p->tpg; 264 265 pr_err("[%s:%d] cmnd[0]=%02x -> st=%02x msg=%02x host=%02x drv=%02x\n", 266 tpg->tport->tport_name, pending_req->v2p->lun, 267 pending_req->cmnd[0], status_byte(errors), msg_byte(errors), 268 host_byte(errors), driver_byte(errors)); 269} 270 271static void scsiback_fast_flush_area(struct vscsibk_pend *req) 272{ 273 struct gnttab_unmap_grant_ref unmap[VSCSI_GRANT_BATCH]; 274 struct page *pages[VSCSI_GRANT_BATCH]; 275 unsigned int i, invcount = 0; 276 grant_handle_t handle; 277 int err; 278 279 kfree(req->sgl); 280 req->sgl = NULL; 281 req->n_sg = 0; 282 283 if (!req->n_grants) 284 return; 285 286 for (i = 0; i < req->n_grants; i++) { 287 handle = req->grant_handles[i]; 288 if (handle == SCSIBACK_INVALID_HANDLE) 289 continue; 290 gnttab_set_unmap_op(&unmap[invcount], vaddr(req, i), 291 GNTMAP_host_map, handle); 292 req->grant_handles[i] = SCSIBACK_INVALID_HANDLE; 293 pages[invcount] = req->pages[i]; 294 put_page(pages[invcount]); 295 invcount++; 296 if (invcount < VSCSI_GRANT_BATCH) 297 continue; 298 err = gnttab_unmap_refs(unmap, NULL, pages, invcount); 299 BUG_ON(err); 300 invcount = 0; 301 } 302 303 if (invcount) { 304 err = gnttab_unmap_refs(unmap, NULL, pages, invcount); 305 BUG_ON(err); 306 } 307 308 put_free_pages(req->pages, req->n_grants); 309 req->n_grants = 0; 310} 311 312static void scsiback_free_translation_entry(struct kref *kref) 313{ 314 struct v2p_entry *entry = container_of(kref, struct v2p_entry, kref); 315 struct scsiback_tpg *tpg = entry->tpg; 316 317 mutex_lock(&tpg->tv_tpg_mutex); 318 tpg->tv_tpg_fe_count--; 319 mutex_unlock(&tpg->tv_tpg_mutex); 320 321 kfree(entry); 322} 323 324static void scsiback_do_resp_with_sense(char *sense_buffer, int32_t result, 325 uint32_t resid, struct vscsibk_pend *pending_req) 326{ 327 struct vscsiif_response *ring_res; 328 struct vscsibk_info *info = pending_req->info; 329 int notify; 330 struct scsi_sense_hdr sshdr; 331 unsigned long flags; 332 unsigned len; 333 334 spin_lock_irqsave(&info->ring_lock, flags); 335 336 ring_res = RING_GET_RESPONSE(&info->ring, info->ring.rsp_prod_pvt); 337 info->ring.rsp_prod_pvt++; 338 339 ring_res->rslt = result; 340 ring_res->rqid = pending_req->rqid; 341 342 if (sense_buffer != NULL && 343 scsi_normalize_sense(sense_buffer, VSCSIIF_SENSE_BUFFERSIZE, 344 &sshdr)) { 345 len = min_t(unsigned, 8 + sense_buffer[7], 346 VSCSIIF_SENSE_BUFFERSIZE); 347 memcpy(ring_res->sense_buffer, sense_buffer, len); 348 ring_res->sense_len = len; 349 } else { 350 ring_res->sense_len = 0; 351 } 352 353 ring_res->residual_len = resid; 354 355 RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(&info->ring, notify); 356 spin_unlock_irqrestore(&info->ring_lock, flags); 357 358 if (notify) 359 notify_remote_via_irq(info->irq); 360 361 if (pending_req->v2p) 362 kref_put(&pending_req->v2p->kref, 363 scsiback_free_translation_entry); 364} 365 366static void scsiback_cmd_done(struct vscsibk_pend *pending_req) 367{ 368 struct vscsibk_info *info = pending_req->info; 369 unsigned char *sense_buffer; 370 unsigned int resid; 371 int errors; 372 373 sense_buffer = pending_req->sense_buffer; 374 resid = pending_req->se_cmd.residual_count; 375 errors = pending_req->result; 376 377 if (errors && log_print_stat) 378 scsiback_print_status(sense_buffer, errors, pending_req); 379 380 scsiback_fast_flush_area(pending_req); 381 scsiback_do_resp_with_sense(sense_buffer, errors, resid, pending_req); 382 scsiback_put(info); 383} 384 385static void scsiback_cmd_exec(struct vscsibk_pend *pending_req) 386{ 387 struct se_cmd *se_cmd = &pending_req->se_cmd; 388 struct se_session *sess = pending_req->v2p->tpg->tpg_nexus->tvn_se_sess; 389 int rc; 390 391 memset(pending_req->sense_buffer, 0, VSCSIIF_SENSE_BUFFERSIZE); 392 393 memset(se_cmd, 0, sizeof(*se_cmd)); 394 395 scsiback_get(pending_req->info); 396 se_cmd->tag = pending_req->rqid; 397 rc = target_submit_cmd_map_sgls(se_cmd, sess, pending_req->cmnd, 398 pending_req->sense_buffer, pending_req->v2p->lun, 399 pending_req->data_len, 0, 400 pending_req->sc_data_direction, 0, 401 pending_req->sgl, pending_req->n_sg, 402 NULL, 0, NULL, 0); 403 if (rc < 0) { 404 transport_send_check_condition_and_sense(se_cmd, 405 TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE, 0); 406 transport_generic_free_cmd(se_cmd, 0); 407 } 408} 409 410static int scsiback_gnttab_data_map_batch(struct gnttab_map_grant_ref *map, 411 struct page **pg, grant_handle_t *grant, int cnt) 412{ 413 int err, i; 414 415 if (!cnt) 416 return 0; 417 418 err = gnttab_map_refs(map, NULL, pg, cnt); 419 BUG_ON(err); 420 for (i = 0; i < cnt; i++) { 421 if (unlikely(map[i].status != GNTST_okay)) { 422 pr_err("invalid buffer -- could not remap it\n"); 423 map[i].handle = SCSIBACK_INVALID_HANDLE; 424 err = -ENOMEM; 425 } else { 426 get_page(pg[i]); 427 } 428 grant[i] = map[i].handle; 429 } 430 return err; 431} 432 433static int scsiback_gnttab_data_map_list(struct vscsibk_pend *pending_req, 434 struct scsiif_request_segment *seg, struct page **pg, 435 grant_handle_t *grant, int cnt, u32 flags) 436{ 437 int mapcount = 0, i, err = 0; 438 struct gnttab_map_grant_ref map[VSCSI_GRANT_BATCH]; 439 struct vscsibk_info *info = pending_req->info; 440 441 for (i = 0; i < cnt; i++) { 442 if (get_free_page(pg + mapcount)) { 443 put_free_pages(pg, mapcount); 444 pr_err("no grant page\n"); 445 return -ENOMEM; 446 } 447 gnttab_set_map_op(&map[mapcount], vaddr_page(pg[mapcount]), 448 flags, seg[i].gref, info->domid); 449 mapcount++; 450 if (mapcount < VSCSI_GRANT_BATCH) 451 continue; 452 err = scsiback_gnttab_data_map_batch(map, pg, grant, mapcount); 453 pg += mapcount; 454 grant += mapcount; 455 pending_req->n_grants += mapcount; 456 if (err) 457 return err; 458 mapcount = 0; 459 } 460 err = scsiback_gnttab_data_map_batch(map, pg, grant, mapcount); 461 pending_req->n_grants += mapcount; 462 return err; 463} 464 465static int scsiback_gnttab_data_map(struct vscsiif_request *ring_req, 466 struct vscsibk_pend *pending_req) 467{ 468 u32 flags; 469 int i, err, n_segs, i_seg = 0; 470 struct page **pg; 471 struct scsiif_request_segment *seg; 472 unsigned long end_seg = 0; 473 unsigned int nr_segments = (unsigned int)ring_req->nr_segments; 474 unsigned int nr_sgl = 0; 475 struct scatterlist *sg; 476 grant_handle_t *grant; 477 478 pending_req->n_sg = 0; 479 pending_req->n_grants = 0; 480 pending_req->data_len = 0; 481 482 nr_segments &= ~VSCSIIF_SG_GRANT; 483 if (!nr_segments) 484 return 0; 485 486 if (nr_segments > VSCSIIF_SG_TABLESIZE) { 487 pr_debug("invalid parameter nr_seg = %d\n", 488 ring_req->nr_segments); 489 return -EINVAL; 490 } 491 492 if (ring_req->nr_segments & VSCSIIF_SG_GRANT) { 493 err = scsiback_gnttab_data_map_list(pending_req, ring_req->seg, 494 pending_req->pages, pending_req->grant_handles, 495 nr_segments, GNTMAP_host_map | GNTMAP_readonly); 496 if (err) 497 return err; 498 nr_sgl = nr_segments; 499 nr_segments = 0; 500 for (i = 0; i < nr_sgl; i++) { 501 n_segs = ring_req->seg[i].length / 502 sizeof(struct scsiif_request_segment); 503 if ((unsigned)ring_req->seg[i].offset + 504 (unsigned)ring_req->seg[i].length > PAGE_SIZE || 505 n_segs * sizeof(struct scsiif_request_segment) != 506 ring_req->seg[i].length) 507 return -EINVAL; 508 nr_segments += n_segs; 509 } 510 if (nr_segments > SG_ALL) { 511 pr_debug("invalid nr_seg = %d\n", nr_segments); 512 return -EINVAL; 513 } 514 } 515 516 /* free of (sgl) in fast_flush_area() */ 517 pending_req->sgl = kmalloc_array(nr_segments, 518 sizeof(struct scatterlist), GFP_KERNEL); 519 if (!pending_req->sgl) 520 return -ENOMEM; 521 522 sg_init_table(pending_req->sgl, nr_segments); 523 pending_req->n_sg = nr_segments; 524 525 flags = GNTMAP_host_map; 526 if (pending_req->sc_data_direction == DMA_TO_DEVICE) 527 flags |= GNTMAP_readonly; 528 529 pg = pending_req->pages + nr_sgl; 530 grant = pending_req->grant_handles + nr_sgl; 531 if (!nr_sgl) { 532 seg = ring_req->seg; 533 err = scsiback_gnttab_data_map_list(pending_req, seg, 534 pg, grant, nr_segments, flags); 535 if (err) 536 return err; 537 } else { 538 for (i = 0; i < nr_sgl; i++) { 539 seg = (struct scsiif_request_segment *)( 540 vaddr(pending_req, i) + ring_req->seg[i].offset); 541 n_segs = ring_req->seg[i].length / 542 sizeof(struct scsiif_request_segment); 543 err = scsiback_gnttab_data_map_list(pending_req, seg, 544 pg, grant, n_segs, flags); 545 if (err) 546 return err; 547 pg += n_segs; 548 grant += n_segs; 549 } 550 end_seg = vaddr(pending_req, 0) + ring_req->seg[0].offset; 551 seg = (struct scsiif_request_segment *)end_seg; 552 end_seg += ring_req->seg[0].length; 553 pg = pending_req->pages + nr_sgl; 554 } 555 556 for_each_sg(pending_req->sgl, sg, nr_segments, i) { 557 sg_set_page(sg, pg[i], seg->length, seg->offset); 558 pending_req->data_len += seg->length; 559 seg++; 560 if (nr_sgl && (unsigned long)seg >= end_seg) { 561 i_seg++; 562 end_seg = vaddr(pending_req, i_seg) + 563 ring_req->seg[i_seg].offset; 564 seg = (struct scsiif_request_segment *)end_seg; 565 end_seg += ring_req->seg[i_seg].length; 566 } 567 if (sg->offset >= PAGE_SIZE || 568 sg->length > PAGE_SIZE || 569 sg->offset + sg->length > PAGE_SIZE) 570 return -EINVAL; 571 } 572 573 return 0; 574} 575 576static void scsiback_disconnect(struct vscsibk_info *info) 577{ 578 wait_event(info->waiting_to_free, 579 atomic_read(&info->nr_unreplied_reqs) == 0); 580 581 unbind_from_irqhandler(info->irq, info); 582 info->irq = 0; 583 xenbus_unmap_ring_vfree(info->dev, info->ring.sring); 584} 585 586static void scsiback_device_action(struct vscsibk_pend *pending_req, 587 enum tcm_tmreq_table act, int tag) 588{ 589 int rc, err = FAILED; 590 struct scsiback_tpg *tpg = pending_req->v2p->tpg; 591 struct se_cmd *se_cmd = &pending_req->se_cmd; 592 struct scsiback_tmr *tmr; 593 594 tmr = kzalloc(sizeof(struct scsiback_tmr), GFP_KERNEL); 595 if (!tmr) 596 goto out; 597 598 init_waitqueue_head(&tmr->tmr_wait); 599 600 transport_init_se_cmd(se_cmd, tpg->se_tpg.se_tpg_tfo, 601 tpg->tpg_nexus->tvn_se_sess, 0, DMA_NONE, TCM_SIMPLE_TAG, 602 &pending_req->sense_buffer[0]); 603 604 rc = core_tmr_alloc_req(se_cmd, tmr, act, GFP_KERNEL); 605 if (rc < 0) 606 goto out; 607 608 se_cmd->se_tmr_req->ref_task_tag = tag; 609 610 if (transport_lookup_tmr_lun(se_cmd, pending_req->v2p->lun) < 0) 611 goto out; 612 613 transport_generic_handle_tmr(se_cmd); 614 wait_event(tmr->tmr_wait, atomic_read(&tmr->tmr_complete)); 615 616 err = (se_cmd->se_tmr_req->response == TMR_FUNCTION_COMPLETE) ? 617 SUCCESS : FAILED; 618 619out: 620 if (tmr) { 621 transport_generic_free_cmd(&pending_req->se_cmd, 1); 622 kfree(tmr); 623 } 624 625 scsiback_do_resp_with_sense(NULL, err, 0, pending_req); 626 627 kmem_cache_free(scsiback_cachep, pending_req); 628} 629 630/* 631 Perform virtual to physical translation 632*/ 633static struct v2p_entry *scsiback_do_translation(struct vscsibk_info *info, 634 struct ids_tuple *v) 635{ 636 struct v2p_entry *entry; 637 struct list_head *head = &(info->v2p_entry_lists); 638 unsigned long flags; 639 640 spin_lock_irqsave(&info->v2p_lock, flags); 641 list_for_each_entry(entry, head, l) { 642 if ((entry->v.chn == v->chn) && 643 (entry->v.tgt == v->tgt) && 644 (entry->v.lun == v->lun)) { 645 kref_get(&entry->kref); 646 goto out; 647 } 648 } 649 entry = NULL; 650 651out: 652 spin_unlock_irqrestore(&info->v2p_lock, flags); 653 return entry; 654} 655 656static int prepare_pending_reqs(struct vscsibk_info *info, 657 struct vscsiif_request *ring_req, 658 struct vscsibk_pend *pending_req) 659{ 660 struct v2p_entry *v2p; 661 struct ids_tuple vir; 662 663 pending_req->rqid = ring_req->rqid; 664 pending_req->info = info; 665 666 vir.chn = ring_req->channel; 667 vir.tgt = ring_req->id; 668 vir.lun = ring_req->lun; 669 670 v2p = scsiback_do_translation(info, &vir); 671 if (!v2p) { 672 pending_req->v2p = NULL; 673 pr_debug("the v2p of (chn:%d, tgt:%d, lun:%d) doesn't exist.\n", 674 vir.chn, vir.tgt, vir.lun); 675 return -ENODEV; 676 } 677 pending_req->v2p = v2p; 678 679 /* request range check from frontend */ 680 pending_req->sc_data_direction = ring_req->sc_data_direction; 681 if ((pending_req->sc_data_direction != DMA_BIDIRECTIONAL) && 682 (pending_req->sc_data_direction != DMA_TO_DEVICE) && 683 (pending_req->sc_data_direction != DMA_FROM_DEVICE) && 684 (pending_req->sc_data_direction != DMA_NONE)) { 685 pr_debug("invalid parameter data_dir = %d\n", 686 pending_req->sc_data_direction); 687 return -EINVAL; 688 } 689 690 pending_req->cmd_len = ring_req->cmd_len; 691 if (pending_req->cmd_len > VSCSIIF_MAX_COMMAND_SIZE) { 692 pr_debug("invalid parameter cmd_len = %d\n", 693 pending_req->cmd_len); 694 return -EINVAL; 695 } 696 memcpy(pending_req->cmnd, ring_req->cmnd, pending_req->cmd_len); 697 698 return 0; 699} 700 701static int scsiback_do_cmd_fn(struct vscsibk_info *info) 702{ 703 struct vscsiif_back_ring *ring = &info->ring; 704 struct vscsiif_request ring_req; 705 struct vscsibk_pend *pending_req; 706 RING_IDX rc, rp; 707 int err, more_to_do; 708 uint32_t result; 709 710 rc = ring->req_cons; 711 rp = ring->sring->req_prod; 712 rmb(); /* guest system is accessing ring, too */ 713 714 if (RING_REQUEST_PROD_OVERFLOW(ring, rp)) { 715 rc = ring->rsp_prod_pvt; 716 pr_warn("Dom%d provided bogus ring requests (%#x - %#x = %u). Halting ring processing\n", 717 info->domid, rp, rc, rp - rc); 718 info->ring_error = 1; 719 return 0; 720 } 721 722 while ((rc != rp)) { 723 if (RING_REQUEST_CONS_OVERFLOW(ring, rc)) 724 break; 725 pending_req = kmem_cache_alloc(scsiback_cachep, GFP_KERNEL); 726 if (!pending_req) 727 return 1; 728 729 RING_COPY_REQUEST(ring, rc, &ring_req); 730 ring->req_cons = ++rc; 731 732 err = prepare_pending_reqs(info, &ring_req, pending_req); 733 if (err) { 734 switch (err) { 735 case -ENODEV: 736 result = DID_NO_CONNECT; 737 break; 738 default: 739 result = DRIVER_ERROR; 740 break; 741 } 742 scsiback_do_resp_with_sense(NULL, result << 24, 0, 743 pending_req); 744 kmem_cache_free(scsiback_cachep, pending_req); 745 return 1; 746 } 747 748 switch (ring_req.act) { 749 case VSCSIIF_ACT_SCSI_CDB: 750 if (scsiback_gnttab_data_map(&ring_req, pending_req)) { 751 scsiback_fast_flush_area(pending_req); 752 scsiback_do_resp_with_sense(NULL, 753 DRIVER_ERROR << 24, 0, pending_req); 754 kmem_cache_free(scsiback_cachep, pending_req); 755 } else { 756 scsiback_cmd_exec(pending_req); 757 } 758 break; 759 case VSCSIIF_ACT_SCSI_ABORT: 760 scsiback_device_action(pending_req, TMR_ABORT_TASK, 761 ring_req.ref_rqid); 762 break; 763 case VSCSIIF_ACT_SCSI_RESET: 764 scsiback_device_action(pending_req, TMR_LUN_RESET, 0); 765 break; 766 default: 767 pr_err_ratelimited("invalid request\n"); 768 scsiback_do_resp_with_sense(NULL, DRIVER_ERROR << 24, 769 0, pending_req); 770 kmem_cache_free(scsiback_cachep, pending_req); 771 break; 772 } 773 774 /* Yield point for this unbounded loop. */ 775 cond_resched(); 776 } 777 778 RING_FINAL_CHECK_FOR_REQUESTS(&info->ring, more_to_do); 779 return more_to_do; 780} 781 782static irqreturn_t scsiback_irq_fn(int irq, void *dev_id) 783{ 784 struct vscsibk_info *info = dev_id; 785 786 if (info->ring_error) 787 return IRQ_HANDLED; 788 789 while (scsiback_do_cmd_fn(info)) 790 cond_resched(); 791 792 return IRQ_HANDLED; 793} 794 795static int scsiback_init_sring(struct vscsibk_info *info, grant_ref_t ring_ref, 796 evtchn_port_t evtchn) 797{ 798 void *area; 799 struct vscsiif_sring *sring; 800 int err; 801 802 if (info->irq) 803 return -1; 804 805 err = xenbus_map_ring_valloc(info->dev, &ring_ref, 1, &area); 806 if (err) 807 return err; 808 809 sring = (struct vscsiif_sring *)area; 810 BACK_RING_INIT(&info->ring, sring, PAGE_SIZE); 811 812 err = bind_interdomain_evtchn_to_irq(info->domid, evtchn); 813 if (err < 0) 814 goto unmap_page; 815 816 info->irq = err; 817 818 err = request_threaded_irq(info->irq, NULL, scsiback_irq_fn, 819 IRQF_ONESHOT, "vscsiif-backend", info); 820 if (err) 821 goto free_irq; 822 823 return 0; 824 825free_irq: 826 unbind_from_irqhandler(info->irq, info); 827 info->irq = 0; 828unmap_page: 829 xenbus_unmap_ring_vfree(info->dev, area); 830 831 return err; 832} 833 834static int scsiback_map(struct vscsibk_info *info) 835{ 836 struct xenbus_device *dev = info->dev; 837 unsigned int ring_ref, evtchn; 838 int err; 839 840 err = xenbus_gather(XBT_NIL, dev->otherend, 841 "ring-ref", "%u", &ring_ref, 842 "event-channel", "%u", &evtchn, NULL); 843 if (err) { 844 xenbus_dev_fatal(dev, err, "reading %s ring", dev->otherend); 845 return err; 846 } 847 848 return scsiback_init_sring(info, ring_ref, evtchn); 849} 850 851/* 852 Add a new translation entry 853*/ 854static int scsiback_add_translation_entry(struct vscsibk_info *info, 855 char *phy, struct ids_tuple *v) 856{ 857 int err = 0; 858 struct v2p_entry *entry; 859 struct v2p_entry *new; 860 struct list_head *head = &(info->v2p_entry_lists); 861 unsigned long flags; 862 char *lunp; 863 unsigned long long unpacked_lun; 864 struct se_lun *se_lun; 865 struct scsiback_tpg *tpg_entry, *tpg = NULL; 866 char *error = "doesn't exist"; 867 868 lunp = strrchr(phy, ':'); 869 if (!lunp) { 870 pr_err("illegal format of physical device %s\n", phy); 871 return -EINVAL; 872 } 873 *lunp = 0; 874 lunp++; 875 err = kstrtoull(lunp, 10, &unpacked_lun); 876 if (err < 0) { 877 pr_err("lun number not valid: %s\n", lunp); 878 return err; 879 } 880 881 mutex_lock(&scsiback_mutex); 882 list_for_each_entry(tpg_entry, &scsiback_list, tv_tpg_list) { 883 if (!strcmp(phy, tpg_entry->tport->tport_name) || 884 !strcmp(phy, tpg_entry->param_alias)) { 885 mutex_lock(&tpg_entry->se_tpg.tpg_lun_mutex); 886 hlist_for_each_entry(se_lun, &tpg_entry->se_tpg.tpg_lun_hlist, link) { 887 if (se_lun->unpacked_lun == unpacked_lun) { 888 if (!tpg_entry->tpg_nexus) 889 error = "nexus undefined"; 890 else 891 tpg = tpg_entry; 892 break; 893 } 894 } 895 mutex_unlock(&tpg_entry->se_tpg.tpg_lun_mutex); 896 break; 897 } 898 } 899 if (tpg) { 900 mutex_lock(&tpg->tv_tpg_mutex); 901 tpg->tv_tpg_fe_count++; 902 mutex_unlock(&tpg->tv_tpg_mutex); 903 } 904 mutex_unlock(&scsiback_mutex); 905 906 if (!tpg) { 907 pr_err("%s:%llu %s\n", phy, unpacked_lun, error); 908 return -ENODEV; 909 } 910 911 new = kmalloc(sizeof(struct v2p_entry), GFP_KERNEL); 912 if (new == NULL) { 913 err = -ENOMEM; 914 goto out_free; 915 } 916 917 spin_lock_irqsave(&info->v2p_lock, flags); 918 919 /* Check double assignment to identical virtual ID */ 920 list_for_each_entry(entry, head, l) { 921 if ((entry->v.chn == v->chn) && 922 (entry->v.tgt == v->tgt) && 923 (entry->v.lun == v->lun)) { 924 pr_warn("Virtual ID is already used. Assignment was not performed.\n"); 925 err = -EEXIST; 926 goto out; 927 } 928 929 } 930 931 /* Create a new translation entry and add to the list */ 932 kref_init(&new->kref); 933 new->v = *v; 934 new->tpg = tpg; 935 new->lun = unpacked_lun; 936 list_add_tail(&new->l, head); 937 938out: 939 spin_unlock_irqrestore(&info->v2p_lock, flags); 940 941out_free: 942 if (err) { 943 mutex_lock(&tpg->tv_tpg_mutex); 944 tpg->tv_tpg_fe_count--; 945 mutex_unlock(&tpg->tv_tpg_mutex); 946 kfree(new); 947 } 948 949 return err; 950} 951 952static void __scsiback_del_translation_entry(struct v2p_entry *entry) 953{ 954 list_del(&entry->l); 955 kref_put(&entry->kref, scsiback_free_translation_entry); 956} 957 958/* 959 Delete the translation entry specfied 960*/ 961static int scsiback_del_translation_entry(struct vscsibk_info *info, 962 struct ids_tuple *v) 963{ 964 struct v2p_entry *entry; 965 struct list_head *head = &(info->v2p_entry_lists); 966 unsigned long flags; 967 968 spin_lock_irqsave(&info->v2p_lock, flags); 969 /* Find out the translation entry specified */ 970 list_for_each_entry(entry, head, l) { 971 if ((entry->v.chn == v->chn) && 972 (entry->v.tgt == v->tgt) && 973 (entry->v.lun == v->lun)) { 974 goto found; 975 } 976 } 977 978 spin_unlock_irqrestore(&info->v2p_lock, flags); 979 return 1; 980 981found: 982 /* Delete the translation entry specfied */ 983 __scsiback_del_translation_entry(entry); 984 985 spin_unlock_irqrestore(&info->v2p_lock, flags); 986 return 0; 987} 988 989static void scsiback_do_add_lun(struct vscsibk_info *info, const char *state, 990 char *phy, struct ids_tuple *vir, int try) 991{ 992 if (!scsiback_add_translation_entry(info, phy, vir)) { 993 if (xenbus_printf(XBT_NIL, info->dev->nodename, state, 994 "%d", XenbusStateInitialised)) { 995 pr_err("xenbus_printf error %s\n", state); 996 scsiback_del_translation_entry(info, vir); 997 } 998 } else if (!try) { 999 xenbus_printf(XBT_NIL, info->dev->nodename, state, 1000 "%d", XenbusStateClosed); 1001 } 1002} 1003 1004static void scsiback_do_del_lun(struct vscsibk_info *info, const char *state, 1005 struct ids_tuple *vir) 1006{ 1007 if (!scsiback_del_translation_entry(info, vir)) { 1008 if (xenbus_printf(XBT_NIL, info->dev->nodename, state, 1009 "%d", XenbusStateClosed)) 1010 pr_err("xenbus_printf error %s\n", state); 1011 } 1012} 1013 1014#define VSCSIBACK_OP_ADD_OR_DEL_LUN 1 1015#define VSCSIBACK_OP_UPDATEDEV_STATE 2 1016 1017static void scsiback_do_1lun_hotplug(struct vscsibk_info *info, int op, 1018 char *ent) 1019{ 1020 int err; 1021 struct ids_tuple vir; 1022 char *val; 1023 int device_state; 1024 char phy[VSCSI_NAMELEN]; 1025 char str[64]; 1026 char state[64]; 1027 struct xenbus_device *dev = info->dev; 1028 1029 /* read status */ 1030 snprintf(state, sizeof(state), "vscsi-devs/%s/state", ent); 1031 err = xenbus_scanf(XBT_NIL, dev->nodename, state, "%u", &device_state); 1032 if (XENBUS_EXIST_ERR(err)) 1033 return; 1034 1035 /* physical SCSI device */ 1036 snprintf(str, sizeof(str), "vscsi-devs/%s/p-dev", ent); 1037 val = xenbus_read(XBT_NIL, dev->nodename, str, NULL); 1038 if (IS_ERR(val)) { 1039 xenbus_printf(XBT_NIL, dev->nodename, state, 1040 "%d", XenbusStateClosed); 1041 return; 1042 } 1043 strlcpy(phy, val, VSCSI_NAMELEN); 1044 kfree(val); 1045 1046 /* virtual SCSI device */ 1047 snprintf(str, sizeof(str), "vscsi-devs/%s/v-dev", ent); 1048 err = xenbus_scanf(XBT_NIL, dev->nodename, str, "%u:%u:%u:%u", 1049 &vir.hst, &vir.chn, &vir.tgt, &vir.lun); 1050 if (XENBUS_EXIST_ERR(err)) { 1051 xenbus_printf(XBT_NIL, dev->nodename, state, 1052 "%d", XenbusStateClosed); 1053 return; 1054 } 1055 1056 switch (op) { 1057 case VSCSIBACK_OP_ADD_OR_DEL_LUN: 1058 switch (device_state) { 1059 case XenbusStateInitialising: 1060 scsiback_do_add_lun(info, state, phy, &vir, 0); 1061 break; 1062 case XenbusStateConnected: 1063 scsiback_do_add_lun(info, state, phy, &vir, 1); 1064 break; 1065 case XenbusStateClosing: 1066 scsiback_do_del_lun(info, state, &vir); 1067 break; 1068 default: 1069 break; 1070 } 1071 break; 1072 1073 case VSCSIBACK_OP_UPDATEDEV_STATE: 1074 if (device_state == XenbusStateInitialised) { 1075 /* modify vscsi-devs/dev-x/state */ 1076 if (xenbus_printf(XBT_NIL, dev->nodename, state, 1077 "%d", XenbusStateConnected)) { 1078 pr_err("xenbus_printf error %s\n", str); 1079 scsiback_del_translation_entry(info, &vir); 1080 xenbus_printf(XBT_NIL, dev->nodename, state, 1081 "%d", XenbusStateClosed); 1082 } 1083 } 1084 break; 1085 /* When it is necessary, processing is added here. */ 1086 default: 1087 break; 1088 } 1089} 1090 1091static void scsiback_do_lun_hotplug(struct vscsibk_info *info, int op) 1092{ 1093 int i; 1094 char **dir; 1095 unsigned int ndir = 0; 1096 1097 dir = xenbus_directory(XBT_NIL, info->dev->nodename, "vscsi-devs", 1098 &ndir); 1099 if (IS_ERR(dir)) 1100 return; 1101 1102 for (i = 0; i < ndir; i++) 1103 scsiback_do_1lun_hotplug(info, op, dir[i]); 1104 1105 kfree(dir); 1106} 1107 1108static void scsiback_frontend_changed(struct xenbus_device *dev, 1109 enum xenbus_state frontend_state) 1110{ 1111 struct vscsibk_info *info = dev_get_drvdata(&dev->dev); 1112 1113 switch (frontend_state) { 1114 case XenbusStateInitialising: 1115 break; 1116 1117 case XenbusStateInitialised: 1118 if (scsiback_map(info)) 1119 break; 1120 1121 scsiback_do_lun_hotplug(info, VSCSIBACK_OP_ADD_OR_DEL_LUN); 1122 xenbus_switch_state(dev, XenbusStateConnected); 1123 break; 1124 1125 case XenbusStateConnected: 1126 scsiback_do_lun_hotplug(info, VSCSIBACK_OP_UPDATEDEV_STATE); 1127 1128 if (dev->state == XenbusStateConnected) 1129 break; 1130 1131 xenbus_switch_state(dev, XenbusStateConnected); 1132 break; 1133 1134 case XenbusStateClosing: 1135 if (info->irq) 1136 scsiback_disconnect(info); 1137 1138 xenbus_switch_state(dev, XenbusStateClosing); 1139 break; 1140 1141 case XenbusStateClosed: 1142 xenbus_switch_state(dev, XenbusStateClosed); 1143 if (xenbus_dev_is_online(dev)) 1144 break; 1145 /* fall through if not online */ 1146 case XenbusStateUnknown: 1147 device_unregister(&dev->dev); 1148 break; 1149 1150 case XenbusStateReconfiguring: 1151 scsiback_do_lun_hotplug(info, VSCSIBACK_OP_ADD_OR_DEL_LUN); 1152 xenbus_switch_state(dev, XenbusStateReconfigured); 1153 1154 break; 1155 1156 default: 1157 xenbus_dev_fatal(dev, -EINVAL, "saw state %d at frontend", 1158 frontend_state); 1159 break; 1160 } 1161} 1162 1163/* 1164 Release the translation entry specfied 1165*/ 1166static void scsiback_release_translation_entry(struct vscsibk_info *info) 1167{ 1168 struct v2p_entry *entry, *tmp; 1169 struct list_head *head = &(info->v2p_entry_lists); 1170 unsigned long flags; 1171 1172 spin_lock_irqsave(&info->v2p_lock, flags); 1173 1174 list_for_each_entry_safe(entry, tmp, head, l) 1175 __scsiback_del_translation_entry(entry); 1176 1177 spin_unlock_irqrestore(&info->v2p_lock, flags); 1178} 1179 1180static int scsiback_remove(struct xenbus_device *dev) 1181{ 1182 struct vscsibk_info *info = dev_get_drvdata(&dev->dev); 1183 1184 if (info->irq) 1185 scsiback_disconnect(info); 1186 1187 scsiback_release_translation_entry(info); 1188 1189 dev_set_drvdata(&dev->dev, NULL); 1190 1191 return 0; 1192} 1193 1194static int scsiback_probe(struct xenbus_device *dev, 1195 const struct xenbus_device_id *id) 1196{ 1197 int err; 1198 1199 struct vscsibk_info *info = kzalloc(sizeof(struct vscsibk_info), 1200 GFP_KERNEL); 1201 1202 pr_debug("%s %p %d\n", __func__, dev, dev->otherend_id); 1203 1204 if (!info) { 1205 xenbus_dev_fatal(dev, -ENOMEM, "allocating backend structure"); 1206 return -ENOMEM; 1207 } 1208 info->dev = dev; 1209 dev_set_drvdata(&dev->dev, info); 1210 1211 info->domid = dev->otherend_id; 1212 spin_lock_init(&info->ring_lock); 1213 info->ring_error = 0; 1214 atomic_set(&info->nr_unreplied_reqs, 0); 1215 init_waitqueue_head(&info->waiting_to_free); 1216 info->dev = dev; 1217 info->irq = 0; 1218 INIT_LIST_HEAD(&info->v2p_entry_lists); 1219 spin_lock_init(&info->v2p_lock); 1220 1221 err = xenbus_printf(XBT_NIL, dev->nodename, "feature-sg-grant", "%u", 1222 SG_ALL); 1223 if (err) 1224 xenbus_dev_error(dev, err, "writing feature-sg-grant"); 1225 1226 err = xenbus_switch_state(dev, XenbusStateInitWait); 1227 if (err) 1228 goto fail; 1229 1230 return 0; 1231 1232fail: 1233 pr_warn("%s failed\n", __func__); 1234 scsiback_remove(dev); 1235 1236 return err; 1237} 1238 1239static char *scsiback_dump_proto_id(struct scsiback_tport *tport) 1240{ 1241 switch (tport->tport_proto_id) { 1242 case SCSI_PROTOCOL_SAS: 1243 return "SAS"; 1244 case SCSI_PROTOCOL_FCP: 1245 return "FCP"; 1246 case SCSI_PROTOCOL_ISCSI: 1247 return "iSCSI"; 1248 default: 1249 break; 1250 } 1251 1252 return "Unknown"; 1253} 1254 1255static char *scsiback_get_fabric_wwn(struct se_portal_group *se_tpg) 1256{ 1257 struct scsiback_tpg *tpg = container_of(se_tpg, 1258 struct scsiback_tpg, se_tpg); 1259 struct scsiback_tport *tport = tpg->tport; 1260 1261 return &tport->tport_name[0]; 1262} 1263 1264static u16 scsiback_get_tag(struct se_portal_group *se_tpg) 1265{ 1266 struct scsiback_tpg *tpg = container_of(se_tpg, 1267 struct scsiback_tpg, se_tpg); 1268 return tpg->tport_tpgt; 1269} 1270 1271static struct se_wwn * 1272scsiback_make_tport(struct target_fabric_configfs *tf, 1273 struct config_group *group, 1274 const char *name) 1275{ 1276 struct scsiback_tport *tport; 1277 char *ptr; 1278 u64 wwpn = 0; 1279 int off = 0; 1280 1281 tport = kzalloc(sizeof(struct scsiback_tport), GFP_KERNEL); 1282 if (!tport) 1283 return ERR_PTR(-ENOMEM); 1284 1285 tport->tport_wwpn = wwpn; 1286 /* 1287 * Determine the emulated Protocol Identifier and Target Port Name 1288 * based on the incoming configfs directory name. 1289 */ 1290 ptr = strstr(name, "naa."); 1291 if (ptr) { 1292 tport->tport_proto_id = SCSI_PROTOCOL_SAS; 1293 goto check_len; 1294 } 1295 ptr = strstr(name, "fc."); 1296 if (ptr) { 1297 tport->tport_proto_id = SCSI_PROTOCOL_FCP; 1298 off = 3; /* Skip over "fc." */ 1299 goto check_len; 1300 } 1301 ptr = strstr(name, "iqn."); 1302 if (ptr) { 1303 tport->tport_proto_id = SCSI_PROTOCOL_ISCSI; 1304 goto check_len; 1305 } 1306 1307 pr_err("Unable to locate prefix for emulated Target Port: %s\n", name); 1308 kfree(tport); 1309 return ERR_PTR(-EINVAL); 1310 1311check_len: 1312 if (strlen(name) >= VSCSI_NAMELEN) { 1313 pr_err("Emulated %s Address: %s, exceeds max: %d\n", name, 1314 scsiback_dump_proto_id(tport), VSCSI_NAMELEN); 1315 kfree(tport); 1316 return ERR_PTR(-EINVAL); 1317 } 1318 snprintf(&tport->tport_name[0], VSCSI_NAMELEN, "%s", &name[off]); 1319 1320 pr_debug("Allocated emulated Target %s Address: %s\n", 1321 scsiback_dump_proto_id(tport), name); 1322 1323 return &tport->tport_wwn; 1324} 1325 1326static void scsiback_drop_tport(struct se_wwn *wwn) 1327{ 1328 struct scsiback_tport *tport = container_of(wwn, 1329 struct scsiback_tport, tport_wwn); 1330 1331 pr_debug("Deallocating emulated Target %s Address: %s\n", 1332 scsiback_dump_proto_id(tport), tport->tport_name); 1333 1334 kfree(tport); 1335} 1336 1337static u32 scsiback_tpg_get_inst_index(struct se_portal_group *se_tpg) 1338{ 1339 return 1; 1340} 1341 1342static int scsiback_check_stop_free(struct se_cmd *se_cmd) 1343{ 1344 /* 1345 * Do not release struct se_cmd's containing a valid TMR pointer. 1346 * These will be released directly in scsiback_device_action() 1347 * with transport_generic_free_cmd(). 1348 */ 1349 if (se_cmd->se_cmd_flags & SCF_SCSI_TMR_CDB) 1350 return 0; 1351 1352 transport_generic_free_cmd(se_cmd, 0); 1353 return 1; 1354} 1355 1356static void scsiback_release_cmd(struct se_cmd *se_cmd) 1357{ 1358 struct vscsibk_pend *pending_req = container_of(se_cmd, 1359 struct vscsibk_pend, se_cmd); 1360 1361 kmem_cache_free(scsiback_cachep, pending_req); 1362} 1363 1364static int scsiback_shutdown_session(struct se_session *se_sess) 1365{ 1366 return 0; 1367} 1368 1369static void scsiback_close_session(struct se_session *se_sess) 1370{ 1371} 1372 1373static u32 scsiback_sess_get_index(struct se_session *se_sess) 1374{ 1375 return 0; 1376} 1377 1378static int scsiback_write_pending(struct se_cmd *se_cmd) 1379{ 1380 /* Go ahead and process the write immediately */ 1381 target_execute_cmd(se_cmd); 1382 1383 return 0; 1384} 1385 1386static int scsiback_write_pending_status(struct se_cmd *se_cmd) 1387{ 1388 return 0; 1389} 1390 1391static void scsiback_set_default_node_attrs(struct se_node_acl *nacl) 1392{ 1393} 1394 1395static int scsiback_get_cmd_state(struct se_cmd *se_cmd) 1396{ 1397 return 0; 1398} 1399 1400static int scsiback_queue_data_in(struct se_cmd *se_cmd) 1401{ 1402 struct vscsibk_pend *pending_req = container_of(se_cmd, 1403 struct vscsibk_pend, se_cmd); 1404 1405 pending_req->result = SAM_STAT_GOOD; 1406 scsiback_cmd_done(pending_req); 1407 return 0; 1408} 1409 1410static int scsiback_queue_status(struct se_cmd *se_cmd) 1411{ 1412 struct vscsibk_pend *pending_req = container_of(se_cmd, 1413 struct vscsibk_pend, se_cmd); 1414 1415 if (se_cmd->sense_buffer && 1416 ((se_cmd->se_cmd_flags & SCF_TRANSPORT_TASK_SENSE) || 1417 (se_cmd->se_cmd_flags & SCF_EMULATED_TASK_SENSE))) 1418 pending_req->result = (DRIVER_SENSE << 24) | 1419 SAM_STAT_CHECK_CONDITION; 1420 else 1421 pending_req->result = se_cmd->scsi_status; 1422 1423 scsiback_cmd_done(pending_req); 1424 return 0; 1425} 1426 1427static void scsiback_queue_tm_rsp(struct se_cmd *se_cmd) 1428{ 1429 struct se_tmr_req *se_tmr = se_cmd->se_tmr_req; 1430 struct scsiback_tmr *tmr = se_tmr->fabric_tmr_ptr; 1431 1432 atomic_set(&tmr->tmr_complete, 1); 1433 wake_up(&tmr->tmr_wait); 1434} 1435 1436static void scsiback_aborted_task(struct se_cmd *se_cmd) 1437{ 1438} 1439 1440static ssize_t scsiback_tpg_param_alias_show(struct config_item *item, 1441 char *page) 1442{ 1443 struct se_portal_group *se_tpg = param_to_tpg(item); 1444 struct scsiback_tpg *tpg = container_of(se_tpg, struct scsiback_tpg, 1445 se_tpg); 1446 ssize_t rb; 1447 1448 mutex_lock(&tpg->tv_tpg_mutex); 1449 rb = snprintf(page, PAGE_SIZE, "%s\n", tpg->param_alias); 1450 mutex_unlock(&tpg->tv_tpg_mutex); 1451 1452 return rb; 1453} 1454 1455static ssize_t scsiback_tpg_param_alias_store(struct config_item *item, 1456 const char *page, size_t count) 1457{ 1458 struct se_portal_group *se_tpg = param_to_tpg(item); 1459 struct scsiback_tpg *tpg = container_of(se_tpg, struct scsiback_tpg, 1460 se_tpg); 1461 int len; 1462 1463 if (strlen(page) >= VSCSI_NAMELEN) { 1464 pr_err("param alias: %s, exceeds max: %d\n", page, 1465 VSCSI_NAMELEN); 1466 return -EINVAL; 1467 } 1468 1469 mutex_lock(&tpg->tv_tpg_mutex); 1470 len = snprintf(tpg->param_alias, VSCSI_NAMELEN, "%s", page); 1471 if (tpg->param_alias[len - 1] == '\n') 1472 tpg->param_alias[len - 1] = '\0'; 1473 mutex_unlock(&tpg->tv_tpg_mutex); 1474 1475 return count; 1476} 1477 1478CONFIGFS_ATTR(scsiback_tpg_param_, alias); 1479 1480static struct configfs_attribute *scsiback_param_attrs[] = { 1481 &scsiback_tpg_param_attr_alias, 1482 NULL, 1483}; 1484 1485static int scsiback_make_nexus(struct scsiback_tpg *tpg, 1486 const char *name) 1487{ 1488 struct se_portal_group *se_tpg; 1489 struct se_session *se_sess; 1490 struct scsiback_nexus *tv_nexus; 1491 1492 mutex_lock(&tpg->tv_tpg_mutex); 1493 if (tpg->tpg_nexus) { 1494 mutex_unlock(&tpg->tv_tpg_mutex); 1495 pr_debug("tpg->tpg_nexus already exists\n"); 1496 return -EEXIST; 1497 } 1498 se_tpg = &tpg->se_tpg; 1499 1500 tv_nexus = kzalloc(sizeof(struct scsiback_nexus), GFP_KERNEL); 1501 if (!tv_nexus) { 1502 mutex_unlock(&tpg->tv_tpg_mutex); 1503 return -ENOMEM; 1504 } 1505 /* 1506 * Initialize the struct se_session pointer 1507 */ 1508 tv_nexus->tvn_se_sess = transport_init_session(TARGET_PROT_NORMAL); 1509 if (IS_ERR(tv_nexus->tvn_se_sess)) { 1510 mutex_unlock(&tpg->tv_tpg_mutex); 1511 kfree(tv_nexus); 1512 return -ENOMEM; 1513 } 1514 se_sess = tv_nexus->tvn_se_sess; 1515 /* 1516 * Since we are running in 'demo mode' this call with generate a 1517 * struct se_node_acl for the scsiback struct se_portal_group with 1518 * the SCSI Initiator port name of the passed configfs group 'name'. 1519 */ 1520 tv_nexus->tvn_se_sess->se_node_acl = core_tpg_check_initiator_node_acl( 1521 se_tpg, (unsigned char *)name); 1522 if (!tv_nexus->tvn_se_sess->se_node_acl) { 1523 mutex_unlock(&tpg->tv_tpg_mutex); 1524 pr_debug("core_tpg_check_initiator_node_acl() failed for %s\n", 1525 name); 1526 goto out; 1527 } 1528 /* Now register the TCM pvscsi virtual I_T Nexus as active. */ 1529 transport_register_session(se_tpg, tv_nexus->tvn_se_sess->se_node_acl, 1530 tv_nexus->tvn_se_sess, tv_nexus); 1531 tpg->tpg_nexus = tv_nexus; 1532 1533 mutex_unlock(&tpg->tv_tpg_mutex); 1534 return 0; 1535 1536out: 1537 transport_free_session(se_sess); 1538 kfree(tv_nexus); 1539 return -ENOMEM; 1540} 1541 1542static int scsiback_drop_nexus(struct scsiback_tpg *tpg) 1543{ 1544 struct se_session *se_sess; 1545 struct scsiback_nexus *tv_nexus; 1546 1547 mutex_lock(&tpg->tv_tpg_mutex); 1548 tv_nexus = tpg->tpg_nexus; 1549 if (!tv_nexus) { 1550 mutex_unlock(&tpg->tv_tpg_mutex); 1551 return -ENODEV; 1552 } 1553 1554 se_sess = tv_nexus->tvn_se_sess; 1555 if (!se_sess) { 1556 mutex_unlock(&tpg->tv_tpg_mutex); 1557 return -ENODEV; 1558 } 1559 1560 if (tpg->tv_tpg_port_count != 0) { 1561 mutex_unlock(&tpg->tv_tpg_mutex); 1562 pr_err("Unable to remove xen-pvscsi I_T Nexus with active TPG port count: %d\n", 1563 tpg->tv_tpg_port_count); 1564 return -EBUSY; 1565 } 1566 1567 if (tpg->tv_tpg_fe_count != 0) { 1568 mutex_unlock(&tpg->tv_tpg_mutex); 1569 pr_err("Unable to remove xen-pvscsi I_T Nexus with active TPG frontend count: %d\n", 1570 tpg->tv_tpg_fe_count); 1571 return -EBUSY; 1572 } 1573 1574 pr_debug("Removing I_T Nexus to emulated %s Initiator Port: %s\n", 1575 scsiback_dump_proto_id(tpg->tport), 1576 tv_nexus->tvn_se_sess->se_node_acl->initiatorname); 1577 1578 /* 1579 * Release the SCSI I_T Nexus to the emulated xen-pvscsi Target Port 1580 */ 1581 transport_deregister_session(tv_nexus->tvn_se_sess); 1582 tpg->tpg_nexus = NULL; 1583 mutex_unlock(&tpg->tv_tpg_mutex); 1584 1585 kfree(tv_nexus); 1586 return 0; 1587} 1588 1589static ssize_t scsiback_tpg_nexus_show(struct config_item *item, char *page) 1590{ 1591 struct se_portal_group *se_tpg = to_tpg(item); 1592 struct scsiback_tpg *tpg = container_of(se_tpg, 1593 struct scsiback_tpg, se_tpg); 1594 struct scsiback_nexus *tv_nexus; 1595 ssize_t ret; 1596 1597 mutex_lock(&tpg->tv_tpg_mutex); 1598 tv_nexus = tpg->tpg_nexus; 1599 if (!tv_nexus) { 1600 mutex_unlock(&tpg->tv_tpg_mutex); 1601 return -ENODEV; 1602 } 1603 ret = snprintf(page, PAGE_SIZE, "%s\n", 1604 tv_nexus->tvn_se_sess->se_node_acl->initiatorname); 1605 mutex_unlock(&tpg->tv_tpg_mutex); 1606 1607 return ret; 1608} 1609 1610static ssize_t scsiback_tpg_nexus_store(struct config_item *item, 1611 const char *page, size_t count) 1612{ 1613 struct se_portal_group *se_tpg = to_tpg(item); 1614 struct scsiback_tpg *tpg = container_of(se_tpg, 1615 struct scsiback_tpg, se_tpg); 1616 struct scsiback_tport *tport_wwn = tpg->tport; 1617 unsigned char i_port[VSCSI_NAMELEN], *ptr, *port_ptr; 1618 int ret; 1619 /* 1620 * Shutdown the active I_T nexus if 'NULL' is passed. 1621 */ 1622 if (!strncmp(page, "NULL", 4)) { 1623 ret = scsiback_drop_nexus(tpg); 1624 return (!ret) ? count : ret; 1625 } 1626 /* 1627 * Otherwise make sure the passed virtual Initiator port WWN matches 1628 * the fabric protocol_id set in scsiback_make_tport(), and call 1629 * scsiback_make_nexus(). 1630 */ 1631 if (strlen(page) >= VSCSI_NAMELEN) { 1632 pr_err("Emulated NAA Sas Address: %s, exceeds max: %d\n", 1633 page, VSCSI_NAMELEN); 1634 return -EINVAL; 1635 } 1636 snprintf(&i_port[0], VSCSI_NAMELEN, "%s", page); 1637 1638 ptr = strstr(i_port, "naa."); 1639 if (ptr) { 1640 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_SAS) { 1641 pr_err("Passed SAS Initiator Port %s does not match target port protoid: %s\n", 1642 i_port, scsiback_dump_proto_id(tport_wwn)); 1643 return -EINVAL; 1644 } 1645 port_ptr = &i_port[0]; 1646 goto check_newline; 1647 } 1648 ptr = strstr(i_port, "fc."); 1649 if (ptr) { 1650 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_FCP) { 1651 pr_err("Passed FCP Initiator Port %s does not match target port protoid: %s\n", 1652 i_port, scsiback_dump_proto_id(tport_wwn)); 1653 return -EINVAL; 1654 } 1655 port_ptr = &i_port[3]; /* Skip over "fc." */ 1656 goto check_newline; 1657 } 1658 ptr = strstr(i_port, "iqn."); 1659 if (ptr) { 1660 if (tport_wwn->tport_proto_id != SCSI_PROTOCOL_ISCSI) { 1661 pr_err("Passed iSCSI Initiator Port %s does not match target port protoid: %s\n", 1662 i_port, scsiback_dump_proto_id(tport_wwn)); 1663 return -EINVAL; 1664 } 1665 port_ptr = &i_port[0]; 1666 goto check_newline; 1667 } 1668 pr_err("Unable to locate prefix for emulated Initiator Port: %s\n", 1669 i_port); 1670 return -EINVAL; 1671 /* 1672 * Clear any trailing newline for the NAA WWN 1673 */ 1674check_newline: 1675 if (i_port[strlen(i_port) - 1] == '\n') 1676 i_port[strlen(i_port) - 1] = '\0'; 1677 1678 ret = scsiback_make_nexus(tpg, port_ptr); 1679 if (ret < 0) 1680 return ret; 1681 1682 return count; 1683} 1684 1685CONFIGFS_ATTR(scsiback_tpg_, nexus); 1686 1687static struct configfs_attribute *scsiback_tpg_attrs[] = { 1688 &scsiback_tpg_attr_nexus, 1689 NULL, 1690}; 1691 1692static ssize_t 1693scsiback_wwn_version_show(struct config_item *item, char *page) 1694{ 1695 return sprintf(page, "xen-pvscsi fabric module %s on %s/%s on " 1696 UTS_RELEASE"\n", 1697 VSCSI_VERSION, utsname()->sysname, utsname()->machine); 1698} 1699 1700CONFIGFS_ATTR_RO(scsiback_wwn_, version); 1701 1702static struct configfs_attribute *scsiback_wwn_attrs[] = { 1703 &scsiback_wwn_attr_version, 1704 NULL, 1705}; 1706 1707static char *scsiback_get_fabric_name(void) 1708{ 1709 return "xen-pvscsi"; 1710} 1711 1712static int scsiback_port_link(struct se_portal_group *se_tpg, 1713 struct se_lun *lun) 1714{ 1715 struct scsiback_tpg *tpg = container_of(se_tpg, 1716 struct scsiback_tpg, se_tpg); 1717 1718 mutex_lock(&tpg->tv_tpg_mutex); 1719 tpg->tv_tpg_port_count++; 1720 mutex_unlock(&tpg->tv_tpg_mutex); 1721 1722 return 0; 1723} 1724 1725static void scsiback_port_unlink(struct se_portal_group *se_tpg, 1726 struct se_lun *lun) 1727{ 1728 struct scsiback_tpg *tpg = container_of(se_tpg, 1729 struct scsiback_tpg, se_tpg); 1730 1731 mutex_lock(&tpg->tv_tpg_mutex); 1732 tpg->tv_tpg_port_count--; 1733 mutex_unlock(&tpg->tv_tpg_mutex); 1734} 1735 1736static struct se_portal_group * 1737scsiback_make_tpg(struct se_wwn *wwn, 1738 struct config_group *group, 1739 const char *name) 1740{ 1741 struct scsiback_tport *tport = container_of(wwn, 1742 struct scsiback_tport, tport_wwn); 1743 1744 struct scsiback_tpg *tpg; 1745 u16 tpgt; 1746 int ret; 1747 1748 if (strstr(name, "tpgt_") != name) 1749 return ERR_PTR(-EINVAL); 1750 ret = kstrtou16(name + 5, 10, &tpgt); 1751 if (ret) 1752 return ERR_PTR(ret); 1753 1754 tpg = kzalloc(sizeof(struct scsiback_tpg), GFP_KERNEL); 1755 if (!tpg) 1756 return ERR_PTR(-ENOMEM); 1757 1758 mutex_init(&tpg->tv_tpg_mutex); 1759 INIT_LIST_HEAD(&tpg->tv_tpg_list); 1760 INIT_LIST_HEAD(&tpg->info_list); 1761 tpg->tport = tport; 1762 tpg->tport_tpgt = tpgt; 1763 1764 ret = core_tpg_register(wwn, &tpg->se_tpg, tport->tport_proto_id); 1765 if (ret < 0) { 1766 kfree(tpg); 1767 return NULL; 1768 } 1769 mutex_lock(&scsiback_mutex); 1770 list_add_tail(&tpg->tv_tpg_list, &scsiback_list); 1771 mutex_unlock(&scsiback_mutex); 1772 1773 return &tpg->se_tpg; 1774} 1775 1776static void scsiback_drop_tpg(struct se_portal_group *se_tpg) 1777{ 1778 struct scsiback_tpg *tpg = container_of(se_tpg, 1779 struct scsiback_tpg, se_tpg); 1780 1781 mutex_lock(&scsiback_mutex); 1782 list_del(&tpg->tv_tpg_list); 1783 mutex_unlock(&scsiback_mutex); 1784 /* 1785 * Release the virtual I_T Nexus for this xen-pvscsi TPG 1786 */ 1787 scsiback_drop_nexus(tpg); 1788 /* 1789 * Deregister the se_tpg from TCM. 1790 */ 1791 core_tpg_deregister(se_tpg); 1792 kfree(tpg); 1793} 1794 1795static int scsiback_check_true(struct se_portal_group *se_tpg) 1796{ 1797 return 1; 1798} 1799 1800static int scsiback_check_false(struct se_portal_group *se_tpg) 1801{ 1802 return 0; 1803} 1804 1805static const struct target_core_fabric_ops scsiback_ops = { 1806 .module = THIS_MODULE, 1807 .name = "xen-pvscsi", 1808 .get_fabric_name = scsiback_get_fabric_name, 1809 .tpg_get_wwn = scsiback_get_fabric_wwn, 1810 .tpg_get_tag = scsiback_get_tag, 1811 .tpg_check_demo_mode = scsiback_check_true, 1812 .tpg_check_demo_mode_cache = scsiback_check_true, 1813 .tpg_check_demo_mode_write_protect = scsiback_check_false, 1814 .tpg_check_prod_mode_write_protect = scsiback_check_false, 1815 .tpg_get_inst_index = scsiback_tpg_get_inst_index, 1816 .check_stop_free = scsiback_check_stop_free, 1817 .release_cmd = scsiback_release_cmd, 1818 .shutdown_session = scsiback_shutdown_session, 1819 .close_session = scsiback_close_session, 1820 .sess_get_index = scsiback_sess_get_index, 1821 .sess_get_initiator_sid = NULL, 1822 .write_pending = scsiback_write_pending, 1823 .write_pending_status = scsiback_write_pending_status, 1824 .set_default_node_attributes = scsiback_set_default_node_attrs, 1825 .get_cmd_state = scsiback_get_cmd_state, 1826 .queue_data_in = scsiback_queue_data_in, 1827 .queue_status = scsiback_queue_status, 1828 .queue_tm_rsp = scsiback_queue_tm_rsp, 1829 .aborted_task = scsiback_aborted_task, 1830 /* 1831 * Setup callers for generic logic in target_core_fabric_configfs.c 1832 */ 1833 .fabric_make_wwn = scsiback_make_tport, 1834 .fabric_drop_wwn = scsiback_drop_tport, 1835 .fabric_make_tpg = scsiback_make_tpg, 1836 .fabric_drop_tpg = scsiback_drop_tpg, 1837 .fabric_post_link = scsiback_port_link, 1838 .fabric_pre_unlink = scsiback_port_unlink, 1839 1840 .tfc_wwn_attrs = scsiback_wwn_attrs, 1841 .tfc_tpg_base_attrs = scsiback_tpg_attrs, 1842 .tfc_tpg_param_attrs = scsiback_param_attrs, 1843}; 1844 1845static const struct xenbus_device_id scsiback_ids[] = { 1846 { "vscsi" }, 1847 { "" } 1848}; 1849 1850static struct xenbus_driver scsiback_driver = { 1851 .ids = scsiback_ids, 1852 .probe = scsiback_probe, 1853 .remove = scsiback_remove, 1854 .otherend_changed = scsiback_frontend_changed 1855}; 1856 1857static void scsiback_init_pend(void *p) 1858{ 1859 struct vscsibk_pend *pend = p; 1860 int i; 1861 1862 memset(pend, 0, sizeof(*pend)); 1863 for (i = 0; i < VSCSI_MAX_GRANTS; i++) 1864 pend->grant_handles[i] = SCSIBACK_INVALID_HANDLE; 1865} 1866 1867static int __init scsiback_init(void) 1868{ 1869 int ret; 1870 1871 if (!xen_domain()) 1872 return -ENODEV; 1873 1874 pr_debug("xen-pvscsi: fabric module %s on %s/%s on "UTS_RELEASE"\n", 1875 VSCSI_VERSION, utsname()->sysname, utsname()->machine); 1876 1877 scsiback_cachep = kmem_cache_create("vscsiif_cache", 1878 sizeof(struct vscsibk_pend), 0, 0, scsiback_init_pend); 1879 if (!scsiback_cachep) 1880 return -ENOMEM; 1881 1882 ret = xenbus_register_backend(&scsiback_driver); 1883 if (ret) 1884 goto out_cache_destroy; 1885 1886 ret = target_register_template(&scsiback_ops); 1887 if (ret) 1888 goto out_unregister_xenbus; 1889 1890 return 0; 1891 1892out_unregister_xenbus: 1893 xenbus_unregister_driver(&scsiback_driver); 1894out_cache_destroy: 1895 kmem_cache_destroy(scsiback_cachep); 1896 pr_err("%s: error %d\n", __func__, ret); 1897 return ret; 1898} 1899 1900static void __exit scsiback_exit(void) 1901{ 1902 struct page *page; 1903 1904 while (free_pages_num) { 1905 if (get_free_page(&page)) 1906 BUG(); 1907 gnttab_free_pages(1, &page); 1908 } 1909 target_unregister_template(&scsiback_ops); 1910 xenbus_unregister_driver(&scsiback_driver); 1911 kmem_cache_destroy(scsiback_cachep); 1912} 1913 1914module_init(scsiback_init); 1915module_exit(scsiback_exit); 1916 1917MODULE_DESCRIPTION("Xen SCSI backend driver"); 1918MODULE_LICENSE("Dual BSD/GPL"); 1919MODULE_ALIAS("xen-backend:vscsi"); 1920MODULE_AUTHOR("Juergen Gross <jgross@suse.com>"); 1921