1 /* 2 * Copyright (c) 2009, Microsoft Corporation. 3 * 4 * This program is free software; you can redistribute it and/or modify it 5 * under the terms and conditions of the GNU General Public License, 6 * version 2, as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope it will be useful, but WITHOUT 9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 11 * more details. 12 * 13 * You should have received a copy of the GNU General Public License along with 14 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple 15 * Place - Suite 330, Boston, MA 02111-1307 USA. 16 * 17 * Authors: 18 * Haiyang Zhang <haiyangz@microsoft.com> 19 * Hank Janssen <hjanssen@microsoft.com> 20 * K. Y. Srinivasan <kys@microsoft.com> 21 */ 22 23 #include <linux/kernel.h> 24 #include <linux/wait.h> 25 #include <linux/sched.h> 26 #include <linux/completion.h> 27 #include <linux/string.h> 28 #include <linux/mm.h> 29 #include <linux/delay.h> 30 #include <linux/init.h> 31 #include <linux/slab.h> 32 #include <linux/module.h> 33 #include <linux/device.h> 34 #include <linux/hyperv.h> 35 #include <linux/mempool.h> 36 #include <scsi/scsi.h> 37 #include <scsi/scsi_cmnd.h> 38 #include <scsi/scsi_host.h> 39 #include <scsi/scsi_device.h> 40 #include <scsi/scsi_tcq.h> 41 #include <scsi/scsi_eh.h> 42 #include <scsi/scsi_devinfo.h> 43 #include <scsi/scsi_dbg.h> 44 45 /* 46 * All wire protocol details (storage protocol between the guest and the host) 47 * are consolidated here. 48 * 49 * Begin protocol definitions. 50 */ 51 52 /* 53 * Version history: 54 * V1 Beta: 0.1 55 * V1 RC < 2008/1/31: 1.0 56 * V1 RC > 2008/1/31: 2.0 57 * Win7: 4.2 58 */ 59 60 #define VMSTOR_CURRENT_MAJOR 4 61 #define VMSTOR_CURRENT_MINOR 2 62 63 64 /* Packet structure describing virtual storage requests. */ 65 enum vstor_packet_operation { 66 VSTOR_OPERATION_COMPLETE_IO = 1, 67 VSTOR_OPERATION_REMOVE_DEVICE = 2, 68 VSTOR_OPERATION_EXECUTE_SRB = 3, 69 VSTOR_OPERATION_RESET_LUN = 4, 70 VSTOR_OPERATION_RESET_ADAPTER = 5, 71 VSTOR_OPERATION_RESET_BUS = 6, 72 VSTOR_OPERATION_BEGIN_INITIALIZATION = 7, 73 VSTOR_OPERATION_END_INITIALIZATION = 8, 74 VSTOR_OPERATION_QUERY_PROTOCOL_VERSION = 9, 75 VSTOR_OPERATION_QUERY_PROPERTIES = 10, 76 VSTOR_OPERATION_ENUMERATE_BUS = 11, 77 VSTOR_OPERATION_MAXIMUM = 11 78 }; 79 80 /* 81 * Platform neutral description of a scsi request - 82 * this remains the same across the write regardless of 32/64 bit 83 * note: it's patterned off the SCSI_PASS_THROUGH structure 84 */ 85 #define STORVSC_MAX_CMD_LEN 0x10 86 #define STORVSC_SENSE_BUFFER_SIZE 0x12 87 #define STORVSC_MAX_BUF_LEN_WITH_PADDING 0x14 88 89 struct vmscsi_request { 90 u16 length; 91 u8 srb_status; 92 u8 scsi_status; 93 94 u8 port_number; 95 u8 path_id; 96 u8 target_id; 97 u8 lun; 98 99 u8 cdb_length; 100 u8 sense_info_length; 101 u8 data_in; 102 u8 reserved; 103 104 u32 data_transfer_length; 105 106 union { 107 u8 cdb[STORVSC_MAX_CMD_LEN]; 108 u8 sense_data[STORVSC_SENSE_BUFFER_SIZE]; 109 u8 reserved_array[STORVSC_MAX_BUF_LEN_WITH_PADDING]; 110 }; 111 } __attribute((packed)); 112 113 114 /* 115 * This structure is sent during the intialization phase to get the different 116 * properties of the channel. 117 */ 118 struct vmstorage_channel_properties { 119 u16 protocol_version; 120 u8 path_id; 121 u8 target_id; 122 123 /* Note: port number is only really known on the client side */ 124 u32 port_number; 125 u32 flags; 126 u32 max_transfer_bytes; 127 128 /* 129 * This id is unique for each channel and will correspond with 130 * vendor specific data in the inquiry data. 131 */ 132 133 u64 unique_id; 134 } __packed; 135 136 /* This structure is sent during the storage protocol negotiations. */ 137 struct vmstorage_protocol_version { 138 /* Major (MSW) and minor (LSW) version numbers. */ 139 u16 major_minor; 140 141 /* 142 * Revision number is auto-incremented whenever this file is changed 143 * (See FILL_VMSTOR_REVISION macro above). Mismatch does not 144 * definitely indicate incompatibility--but it does indicate mismatched 145 * builds. 146 * This is only used on the windows side. Just set it to 0. 147 */ 148 u16 revision; 149 } __packed; 150 151 /* Channel Property Flags */ 152 #define STORAGE_CHANNEL_REMOVABLE_FLAG 0x1 153 #define STORAGE_CHANNEL_EMULATED_IDE_FLAG 0x2 154 155 struct vstor_packet { 156 /* Requested operation type */ 157 enum vstor_packet_operation operation; 158 159 /* Flags - see below for values */ 160 u32 flags; 161 162 /* Status of the request returned from the server side. */ 163 u32 status; 164 165 /* Data payload area */ 166 union { 167 /* 168 * Structure used to forward SCSI commands from the 169 * client to the server. 170 */ 171 struct vmscsi_request vm_srb; 172 173 /* Structure used to query channel properties. */ 174 struct vmstorage_channel_properties storage_channel_properties; 175 176 /* Used during version negotiations. */ 177 struct vmstorage_protocol_version version; 178 }; 179 } __packed; 180 181 /* 182 * Packet Flags: 183 * 184 * This flag indicates that the server should send back a completion for this 185 * packet. 186 */ 187 188 #define REQUEST_COMPLETION_FLAG 0x1 189 190 /* Matches Windows-end */ 191 enum storvsc_request_type { 192 WRITE_TYPE = 0, 193 READ_TYPE, 194 UNKNOWN_TYPE, 195 }; 196 197 /* 198 * SRB status codes and masks; a subset of the codes used here. 199 */ 200 201 #define SRB_STATUS_AUTOSENSE_VALID 0x80 202 #define SRB_STATUS_INVALID_LUN 0x20 203 #define SRB_STATUS_SUCCESS 0x01 204 #define SRB_STATUS_ABORTED 0x02 205 #define SRB_STATUS_ERROR 0x04 206 207 /* 208 * This is the end of Protocol specific defines. 209 */ 210 211 212 /* 213 * We setup a mempool to allocate request structures for this driver 214 * on a per-lun basis. The following define specifies the number of 215 * elements in the pool. 216 */ 217 218 #define STORVSC_MIN_BUF_NR 64 219 static int storvsc_ringbuffer_size = (20 * PAGE_SIZE); 220 221 module_param(storvsc_ringbuffer_size, int, S_IRUGO); 222 MODULE_PARM_DESC(storvsc_ringbuffer_size, "Ring buffer size (bytes)"); 223 224 #define STORVSC_MAX_IO_REQUESTS 128 225 226 /* 227 * In Hyper-V, each port/path/target maps to 1 scsi host adapter. In 228 * reality, the path/target is not used (ie always set to 0) so our 229 * scsi host adapter essentially has 1 bus with 1 target that contains 230 * up to 256 luns. 231 */ 232 #define STORVSC_MAX_LUNS_PER_TARGET 64 233 #define STORVSC_MAX_TARGETS 1 234 #define STORVSC_MAX_CHANNELS 1 235 236 237 238 struct storvsc_cmd_request { 239 struct list_head entry; 240 struct scsi_cmnd *cmd; 241 242 unsigned int bounce_sgl_count; 243 struct scatterlist *bounce_sgl; 244 245 struct hv_device *device; 246 247 /* Synchronize the request/response if needed */ 248 struct completion wait_event; 249 250 unsigned char *sense_buffer; 251 struct hv_multipage_buffer data_buffer; 252 struct vstor_packet vstor_packet; 253 }; 254 255 256 /* A storvsc device is a device object that contains a vmbus channel */ 257 struct storvsc_device { 258 struct hv_device *device; 259 260 bool destroy; 261 bool drain_notify; 262 atomic_t num_outstanding_req; 263 struct Scsi_Host *host; 264 265 wait_queue_head_t waiting_to_drain; 266 267 /* 268 * Each unique Port/Path/Target represents 1 channel ie scsi 269 * controller. In reality, the pathid, targetid is always 0 270 * and the port is set by us 271 */ 272 unsigned int port_number; 273 unsigned char path_id; 274 unsigned char target_id; 275 276 /* Used for vsc/vsp channel reset process */ 277 struct storvsc_cmd_request init_request; 278 struct storvsc_cmd_request reset_request; 279 }; 280 281 struct stor_mem_pools { 282 struct kmem_cache *request_pool; 283 mempool_t *request_mempool; 284 }; 285 286 struct hv_host_device { 287 struct hv_device *dev; 288 unsigned int port; 289 unsigned char path; 290 unsigned char target; 291 }; 292 293 struct storvsc_scan_work { 294 struct work_struct work; 295 struct Scsi_Host *host; 296 uint lun; 297 }; 298 299 static void storvsc_device_scan(struct work_struct *work) 300 { 301 struct storvsc_scan_work *wrk; 302 uint lun; 303 struct scsi_device *sdev; 304 305 wrk = container_of(work, struct storvsc_scan_work, work); 306 lun = wrk->lun; 307 308 sdev = scsi_device_lookup(wrk->host, 0, 0, lun); 309 if (!sdev) 310 goto done; 311 scsi_rescan_device(&sdev->sdev_gendev); 312 scsi_device_put(sdev); 313 314 done: 315 kfree(wrk); 316 } 317 318 static void storvsc_bus_scan(struct work_struct *work) 319 { 320 struct storvsc_scan_work *wrk; 321 int id, order_id; 322 323 wrk = container_of(work, struct storvsc_scan_work, work); 324 for (id = 0; id < wrk->host->max_id; ++id) { 325 if (wrk->host->reverse_ordering) 326 order_id = wrk->host->max_id - id - 1; 327 else 328 order_id = id; 329 330 scsi_scan_target(&wrk->host->shost_gendev, 0, 331 order_id, SCAN_WILD_CARD, 1); 332 } 333 kfree(wrk); 334 } 335 336 static void storvsc_remove_lun(struct work_struct *work) 337 { 338 struct storvsc_scan_work *wrk; 339 struct scsi_device *sdev; 340 341 wrk = container_of(work, struct storvsc_scan_work, work); 342 if (!scsi_host_get(wrk->host)) 343 goto done; 344 345 sdev = scsi_device_lookup(wrk->host, 0, 0, wrk->lun); 346 347 if (sdev) { 348 scsi_remove_device(sdev); 349 scsi_device_put(sdev); 350 } 351 scsi_host_put(wrk->host); 352 353 done: 354 kfree(wrk); 355 } 356 357 /* 358 * Major/minor macros. Minor version is in LSB, meaning that earlier flat 359 * version numbers will be interpreted as "0.x" (i.e., 1 becomes 0.1). 360 */ 361 362 static inline u16 storvsc_get_version(u8 major, u8 minor) 363 { 364 u16 version; 365 366 version = ((major << 8) | minor); 367 return version; 368 } 369 370 /* 371 * We can get incoming messages from the host that are not in response to 372 * messages that we have sent out. An example of this would be messages 373 * received by the guest to notify dynamic addition/removal of LUNs. To 374 * deal with potential race conditions where the driver may be in the 375 * midst of being unloaded when we might receive an unsolicited message 376 * from the host, we have implemented a mechanism to gurantee sequential 377 * consistency: 378 * 379 * 1) Once the device is marked as being destroyed, we will fail all 380 * outgoing messages. 381 * 2) We permit incoming messages when the device is being destroyed, 382 * only to properly account for messages already sent out. 383 */ 384 385 static inline struct storvsc_device *get_out_stor_device( 386 struct hv_device *device) 387 { 388 struct storvsc_device *stor_device; 389 390 stor_device = hv_get_drvdata(device); 391 392 if (stor_device && stor_device->destroy) 393 stor_device = NULL; 394 395 return stor_device; 396 } 397 398 399 static inline void storvsc_wait_to_drain(struct storvsc_device *dev) 400 { 401 dev->drain_notify = true; 402 wait_event(dev->waiting_to_drain, 403 atomic_read(&dev->num_outstanding_req) == 0); 404 dev->drain_notify = false; 405 } 406 407 static inline struct storvsc_device *get_in_stor_device( 408 struct hv_device *device) 409 { 410 struct storvsc_device *stor_device; 411 412 stor_device = hv_get_drvdata(device); 413 414 if (!stor_device) 415 goto get_in_err; 416 417 /* 418 * If the device is being destroyed; allow incoming 419 * traffic only to cleanup outstanding requests. 420 */ 421 422 if (stor_device->destroy && 423 (atomic_read(&stor_device->num_outstanding_req) == 0)) 424 stor_device = NULL; 425 426 get_in_err: 427 return stor_device; 428 429 } 430 431 static void destroy_bounce_buffer(struct scatterlist *sgl, 432 unsigned int sg_count) 433 { 434 int i; 435 struct page *page_buf; 436 437 for (i = 0; i < sg_count; i++) { 438 page_buf = sg_page((&sgl[i])); 439 if (page_buf != NULL) 440 __free_page(page_buf); 441 } 442 443 kfree(sgl); 444 } 445 446 static int do_bounce_buffer(struct scatterlist *sgl, unsigned int sg_count) 447 { 448 int i; 449 450 /* No need to check */ 451 if (sg_count < 2) 452 return -1; 453 454 /* We have at least 2 sg entries */ 455 for (i = 0; i < sg_count; i++) { 456 if (i == 0) { 457 /* make sure 1st one does not have hole */ 458 if (sgl[i].offset + sgl[i].length != PAGE_SIZE) 459 return i; 460 } else if (i == sg_count - 1) { 461 /* make sure last one does not have hole */ 462 if (sgl[i].offset != 0) 463 return i; 464 } else { 465 /* make sure no hole in the middle */ 466 if (sgl[i].length != PAGE_SIZE || sgl[i].offset != 0) 467 return i; 468 } 469 } 470 return -1; 471 } 472 473 static struct scatterlist *create_bounce_buffer(struct scatterlist *sgl, 474 unsigned int sg_count, 475 unsigned int len, 476 int write) 477 { 478 int i; 479 int num_pages; 480 struct scatterlist *bounce_sgl; 481 struct page *page_buf; 482 unsigned int buf_len = ((write == WRITE_TYPE) ? 0 : PAGE_SIZE); 483 484 num_pages = ALIGN(len, PAGE_SIZE) >> PAGE_SHIFT; 485 486 bounce_sgl = kcalloc(num_pages, sizeof(struct scatterlist), GFP_ATOMIC); 487 if (!bounce_sgl) 488 return NULL; 489 490 sg_init_table(bounce_sgl, num_pages); 491 for (i = 0; i < num_pages; i++) { 492 page_buf = alloc_page(GFP_ATOMIC); 493 if (!page_buf) 494 goto cleanup; 495 sg_set_page(&bounce_sgl[i], page_buf, buf_len, 0); 496 } 497 498 return bounce_sgl; 499 500 cleanup: 501 destroy_bounce_buffer(bounce_sgl, num_pages); 502 return NULL; 503 } 504 505 /* Disgusting wrapper functions */ 506 static inline unsigned long sg_kmap_atomic(struct scatterlist *sgl, int idx) 507 { 508 void *addr = kmap_atomic(sg_page(sgl + idx)); 509 return (unsigned long)addr; 510 } 511 512 static inline void sg_kunmap_atomic(unsigned long addr) 513 { 514 kunmap_atomic((void *)addr); 515 } 516 517 518 /* Assume the original sgl has enough room */ 519 static unsigned int copy_from_bounce_buffer(struct scatterlist *orig_sgl, 520 struct scatterlist *bounce_sgl, 521 unsigned int orig_sgl_count, 522 unsigned int bounce_sgl_count) 523 { 524 int i; 525 int j = 0; 526 unsigned long src, dest; 527 unsigned int srclen, destlen, copylen; 528 unsigned int total_copied = 0; 529 unsigned long bounce_addr = 0; 530 unsigned long dest_addr = 0; 531 unsigned long flags; 532 533 local_irq_save(flags); 534 535 for (i = 0; i < orig_sgl_count; i++) { 536 dest_addr = sg_kmap_atomic(orig_sgl,i) + orig_sgl[i].offset; 537 dest = dest_addr; 538 destlen = orig_sgl[i].length; 539 540 if (bounce_addr == 0) 541 bounce_addr = sg_kmap_atomic(bounce_sgl,j); 542 543 while (destlen) { 544 src = bounce_addr + bounce_sgl[j].offset; 545 srclen = bounce_sgl[j].length - bounce_sgl[j].offset; 546 547 copylen = min(srclen, destlen); 548 memcpy((void *)dest, (void *)src, copylen); 549 550 total_copied += copylen; 551 bounce_sgl[j].offset += copylen; 552 destlen -= copylen; 553 dest += copylen; 554 555 if (bounce_sgl[j].offset == bounce_sgl[j].length) { 556 /* full */ 557 sg_kunmap_atomic(bounce_addr); 558 j++; 559 560 /* 561 * It is possible that the number of elements 562 * in the bounce buffer may not be equal to 563 * the number of elements in the original 564 * scatter list. Handle this correctly. 565 */ 566 567 if (j == bounce_sgl_count) { 568 /* 569 * We are done; cleanup and return. 570 */ 571 sg_kunmap_atomic(dest_addr - orig_sgl[i].offset); 572 local_irq_restore(flags); 573 return total_copied; 574 } 575 576 /* if we need to use another bounce buffer */ 577 if (destlen || i != orig_sgl_count - 1) 578 bounce_addr = sg_kmap_atomic(bounce_sgl,j); 579 } else if (destlen == 0 && i == orig_sgl_count - 1) { 580 /* unmap the last bounce that is < PAGE_SIZE */ 581 sg_kunmap_atomic(bounce_addr); 582 } 583 } 584 585 sg_kunmap_atomic(dest_addr - orig_sgl[i].offset); 586 } 587 588 local_irq_restore(flags); 589 590 return total_copied; 591 } 592 593 /* Assume the bounce_sgl has enough room ie using the create_bounce_buffer() */ 594 static unsigned int copy_to_bounce_buffer(struct scatterlist *orig_sgl, 595 struct scatterlist *bounce_sgl, 596 unsigned int orig_sgl_count) 597 { 598 int i; 599 int j = 0; 600 unsigned long src, dest; 601 unsigned int srclen, destlen, copylen; 602 unsigned int total_copied = 0; 603 unsigned long bounce_addr = 0; 604 unsigned long src_addr = 0; 605 unsigned long flags; 606 607 local_irq_save(flags); 608 609 for (i = 0; i < orig_sgl_count; i++) { 610 src_addr = sg_kmap_atomic(orig_sgl,i) + orig_sgl[i].offset; 611 src = src_addr; 612 srclen = orig_sgl[i].length; 613 614 if (bounce_addr == 0) 615 bounce_addr = sg_kmap_atomic(bounce_sgl,j); 616 617 while (srclen) { 618 /* assume bounce offset always == 0 */ 619 dest = bounce_addr + bounce_sgl[j].length; 620 destlen = PAGE_SIZE - bounce_sgl[j].length; 621 622 copylen = min(srclen, destlen); 623 memcpy((void *)dest, (void *)src, copylen); 624 625 total_copied += copylen; 626 bounce_sgl[j].length += copylen; 627 srclen -= copylen; 628 src += copylen; 629 630 if (bounce_sgl[j].length == PAGE_SIZE) { 631 /* full..move to next entry */ 632 sg_kunmap_atomic(bounce_addr); 633 j++; 634 635 /* if we need to use another bounce buffer */ 636 if (srclen || i != orig_sgl_count - 1) 637 bounce_addr = sg_kmap_atomic(bounce_sgl,j); 638 639 } else if (srclen == 0 && i == orig_sgl_count - 1) { 640 /* unmap the last bounce that is < PAGE_SIZE */ 641 sg_kunmap_atomic(bounce_addr); 642 } 643 } 644 645 sg_kunmap_atomic(src_addr - orig_sgl[i].offset); 646 } 647 648 local_irq_restore(flags); 649 650 return total_copied; 651 } 652 653 static int storvsc_channel_init(struct hv_device *device) 654 { 655 struct storvsc_device *stor_device; 656 struct storvsc_cmd_request *request; 657 struct vstor_packet *vstor_packet; 658 int ret, t; 659 660 stor_device = get_out_stor_device(device); 661 if (!stor_device) 662 return -ENODEV; 663 664 request = &stor_device->init_request; 665 vstor_packet = &request->vstor_packet; 666 667 /* 668 * Now, initiate the vsc/vsp initialization protocol on the open 669 * channel 670 */ 671 memset(request, 0, sizeof(struct storvsc_cmd_request)); 672 init_completion(&request->wait_event); 673 vstor_packet->operation = VSTOR_OPERATION_BEGIN_INITIALIZATION; 674 vstor_packet->flags = REQUEST_COMPLETION_FLAG; 675 676 ret = vmbus_sendpacket(device->channel, vstor_packet, 677 sizeof(struct vstor_packet), 678 (unsigned long)request, 679 VM_PKT_DATA_INBAND, 680 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); 681 if (ret != 0) 682 goto cleanup; 683 684 t = wait_for_completion_timeout(&request->wait_event, 5*HZ); 685 if (t == 0) { 686 ret = -ETIMEDOUT; 687 goto cleanup; 688 } 689 690 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO || 691 vstor_packet->status != 0) 692 goto cleanup; 693 694 695 /* reuse the packet for version range supported */ 696 memset(vstor_packet, 0, sizeof(struct vstor_packet)); 697 vstor_packet->operation = VSTOR_OPERATION_QUERY_PROTOCOL_VERSION; 698 vstor_packet->flags = REQUEST_COMPLETION_FLAG; 699 700 vstor_packet->version.major_minor = 701 storvsc_get_version(VMSTOR_CURRENT_MAJOR, VMSTOR_CURRENT_MINOR); 702 703 /* 704 * The revision number is only used in Windows; set it to 0. 705 */ 706 vstor_packet->version.revision = 0; 707 708 ret = vmbus_sendpacket(device->channel, vstor_packet, 709 sizeof(struct vstor_packet), 710 (unsigned long)request, 711 VM_PKT_DATA_INBAND, 712 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); 713 if (ret != 0) 714 goto cleanup; 715 716 t = wait_for_completion_timeout(&request->wait_event, 5*HZ); 717 if (t == 0) { 718 ret = -ETIMEDOUT; 719 goto cleanup; 720 } 721 722 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO || 723 vstor_packet->status != 0) 724 goto cleanup; 725 726 727 memset(vstor_packet, 0, sizeof(struct vstor_packet)); 728 vstor_packet->operation = VSTOR_OPERATION_QUERY_PROPERTIES; 729 vstor_packet->flags = REQUEST_COMPLETION_FLAG; 730 vstor_packet->storage_channel_properties.port_number = 731 stor_device->port_number; 732 733 ret = vmbus_sendpacket(device->channel, vstor_packet, 734 sizeof(struct vstor_packet), 735 (unsigned long)request, 736 VM_PKT_DATA_INBAND, 737 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); 738 739 if (ret != 0) 740 goto cleanup; 741 742 t = wait_for_completion_timeout(&request->wait_event, 5*HZ); 743 if (t == 0) { 744 ret = -ETIMEDOUT; 745 goto cleanup; 746 } 747 748 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO || 749 vstor_packet->status != 0) 750 goto cleanup; 751 752 stor_device->path_id = vstor_packet->storage_channel_properties.path_id; 753 stor_device->target_id 754 = vstor_packet->storage_channel_properties.target_id; 755 756 memset(vstor_packet, 0, sizeof(struct vstor_packet)); 757 vstor_packet->operation = VSTOR_OPERATION_END_INITIALIZATION; 758 vstor_packet->flags = REQUEST_COMPLETION_FLAG; 759 760 ret = vmbus_sendpacket(device->channel, vstor_packet, 761 sizeof(struct vstor_packet), 762 (unsigned long)request, 763 VM_PKT_DATA_INBAND, 764 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); 765 766 if (ret != 0) 767 goto cleanup; 768 769 t = wait_for_completion_timeout(&request->wait_event, 5*HZ); 770 if (t == 0) { 771 ret = -ETIMEDOUT; 772 goto cleanup; 773 } 774 775 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO || 776 vstor_packet->status != 0) 777 goto cleanup; 778 779 780 cleanup: 781 return ret; 782 } 783 784 static void storvsc_handle_error(struct vmscsi_request *vm_srb, 785 struct scsi_cmnd *scmnd, 786 struct Scsi_Host *host, 787 u8 asc, u8 ascq) 788 { 789 struct storvsc_scan_work *wrk; 790 void (*process_err_fn)(struct work_struct *work); 791 bool do_work = false; 792 793 switch (vm_srb->srb_status) { 794 case SRB_STATUS_ERROR: 795 /* 796 * If there is an error; offline the device since all 797 * error recovery strategies would have already been 798 * deployed on the host side. However, if the command 799 * were a pass-through command deal with it appropriately. 800 */ 801 switch (scmnd->cmnd[0]) { 802 case ATA_16: 803 case ATA_12: 804 set_host_byte(scmnd, DID_PASSTHROUGH); 805 break; 806 default: 807 set_host_byte(scmnd, DID_TARGET_FAILURE); 808 } 809 break; 810 case SRB_STATUS_INVALID_LUN: 811 do_work = true; 812 process_err_fn = storvsc_remove_lun; 813 break; 814 case (SRB_STATUS_ABORTED | SRB_STATUS_AUTOSENSE_VALID): 815 if ((asc == 0x2a) && (ascq == 0x9)) { 816 do_work = true; 817 process_err_fn = storvsc_device_scan; 818 /* 819 * Retry the I/O that trigerred this. 820 */ 821 set_host_byte(scmnd, DID_REQUEUE); 822 } 823 break; 824 } 825 826 if (!do_work) 827 return; 828 829 /* 830 * We need to schedule work to process this error; schedule it. 831 */ 832 wrk = kmalloc(sizeof(struct storvsc_scan_work), GFP_ATOMIC); 833 if (!wrk) { 834 set_host_byte(scmnd, DID_TARGET_FAILURE); 835 return; 836 } 837 838 wrk->host = host; 839 wrk->lun = vm_srb->lun; 840 INIT_WORK(&wrk->work, process_err_fn); 841 schedule_work(&wrk->work); 842 } 843 844 845 static void storvsc_command_completion(struct storvsc_cmd_request *cmd_request) 846 { 847 struct scsi_cmnd *scmnd = cmd_request->cmd; 848 struct hv_host_device *host_dev = shost_priv(scmnd->device->host); 849 void (*scsi_done_fn)(struct scsi_cmnd *); 850 struct scsi_sense_hdr sense_hdr; 851 struct vmscsi_request *vm_srb; 852 struct stor_mem_pools *memp = scmnd->device->hostdata; 853 struct Scsi_Host *host; 854 struct storvsc_device *stor_dev; 855 struct hv_device *dev = host_dev->dev; 856 857 stor_dev = get_in_stor_device(dev); 858 host = stor_dev->host; 859 860 vm_srb = &cmd_request->vstor_packet.vm_srb; 861 if (cmd_request->bounce_sgl_count) { 862 if (vm_srb->data_in == READ_TYPE) 863 copy_from_bounce_buffer(scsi_sglist(scmnd), 864 cmd_request->bounce_sgl, 865 scsi_sg_count(scmnd), 866 cmd_request->bounce_sgl_count); 867 destroy_bounce_buffer(cmd_request->bounce_sgl, 868 cmd_request->bounce_sgl_count); 869 } 870 871 scmnd->result = vm_srb->scsi_status; 872 873 if (scmnd->result) { 874 if (scsi_normalize_sense(scmnd->sense_buffer, 875 SCSI_SENSE_BUFFERSIZE, &sense_hdr)) 876 scsi_print_sense_hdr("storvsc", &sense_hdr); 877 } 878 879 if (vm_srb->srb_status != SRB_STATUS_SUCCESS) 880 storvsc_handle_error(vm_srb, scmnd, host, sense_hdr.asc, 881 sense_hdr.ascq); 882 883 scsi_set_resid(scmnd, 884 cmd_request->data_buffer.len - 885 vm_srb->data_transfer_length); 886 887 scsi_done_fn = scmnd->scsi_done; 888 889 scmnd->host_scribble = NULL; 890 scmnd->scsi_done = NULL; 891 892 scsi_done_fn(scmnd); 893 894 mempool_free(cmd_request, memp->request_mempool); 895 } 896 897 static void storvsc_on_io_completion(struct hv_device *device, 898 struct vstor_packet *vstor_packet, 899 struct storvsc_cmd_request *request) 900 { 901 struct storvsc_device *stor_device; 902 struct vstor_packet *stor_pkt; 903 904 stor_device = hv_get_drvdata(device); 905 stor_pkt = &request->vstor_packet; 906 907 /* 908 * The current SCSI handling on the host side does 909 * not correctly handle: 910 * INQUIRY command with page code parameter set to 0x80 911 * MODE_SENSE command with cmd[2] == 0x1c 912 * 913 * Setup srb and scsi status so this won't be fatal. 914 * We do this so we can distinguish truly fatal failues 915 * (srb status == 0x4) and off-line the device in that case. 916 */ 917 918 if ((stor_pkt->vm_srb.cdb[0] == INQUIRY) || 919 (stor_pkt->vm_srb.cdb[0] == MODE_SENSE)) { 920 vstor_packet->vm_srb.scsi_status = 0; 921 vstor_packet->vm_srb.srb_status = SRB_STATUS_SUCCESS; 922 } 923 924 925 /* Copy over the status...etc */ 926 stor_pkt->vm_srb.scsi_status = vstor_packet->vm_srb.scsi_status; 927 stor_pkt->vm_srb.srb_status = vstor_packet->vm_srb.srb_status; 928 stor_pkt->vm_srb.sense_info_length = 929 vstor_packet->vm_srb.sense_info_length; 930 931 if (vstor_packet->vm_srb.scsi_status != 0 || 932 vstor_packet->vm_srb.srb_status != SRB_STATUS_SUCCESS){ 933 dev_warn(&device->device, 934 "cmd 0x%x scsi status 0x%x srb status 0x%x\n", 935 stor_pkt->vm_srb.cdb[0], 936 vstor_packet->vm_srb.scsi_status, 937 vstor_packet->vm_srb.srb_status); 938 } 939 940 if ((vstor_packet->vm_srb.scsi_status & 0xFF) == 0x02) { 941 /* CHECK_CONDITION */ 942 if (vstor_packet->vm_srb.srb_status & 943 SRB_STATUS_AUTOSENSE_VALID) { 944 /* autosense data available */ 945 dev_warn(&device->device, 946 "stor pkt %p autosense data valid - len %d\n", 947 request, 948 vstor_packet->vm_srb.sense_info_length); 949 950 memcpy(request->sense_buffer, 951 vstor_packet->vm_srb.sense_data, 952 vstor_packet->vm_srb.sense_info_length); 953 954 } 955 } 956 957 stor_pkt->vm_srb.data_transfer_length = 958 vstor_packet->vm_srb.data_transfer_length; 959 960 storvsc_command_completion(request); 961 962 if (atomic_dec_and_test(&stor_device->num_outstanding_req) && 963 stor_device->drain_notify) 964 wake_up(&stor_device->waiting_to_drain); 965 966 967 } 968 969 static void storvsc_on_receive(struct hv_device *device, 970 struct vstor_packet *vstor_packet, 971 struct storvsc_cmd_request *request) 972 { 973 struct storvsc_scan_work *work; 974 struct storvsc_device *stor_device; 975 976 switch (vstor_packet->operation) { 977 case VSTOR_OPERATION_COMPLETE_IO: 978 storvsc_on_io_completion(device, vstor_packet, request); 979 break; 980 981 case VSTOR_OPERATION_REMOVE_DEVICE: 982 case VSTOR_OPERATION_ENUMERATE_BUS: 983 stor_device = get_in_stor_device(device); 984 work = kmalloc(sizeof(struct storvsc_scan_work), GFP_ATOMIC); 985 if (!work) 986 return; 987 988 INIT_WORK(&work->work, storvsc_bus_scan); 989 work->host = stor_device->host; 990 schedule_work(&work->work); 991 break; 992 993 default: 994 break; 995 } 996 } 997 998 static void storvsc_on_channel_callback(void *context) 999 { 1000 struct hv_device *device = (struct hv_device *)context; 1001 struct storvsc_device *stor_device; 1002 u32 bytes_recvd; 1003 u64 request_id; 1004 unsigned char packet[ALIGN(sizeof(struct vstor_packet), 8)]; 1005 struct storvsc_cmd_request *request; 1006 int ret; 1007 1008 1009 stor_device = get_in_stor_device(device); 1010 if (!stor_device) 1011 return; 1012 1013 do { 1014 ret = vmbus_recvpacket(device->channel, packet, 1015 ALIGN(sizeof(struct vstor_packet), 8), 1016 &bytes_recvd, &request_id); 1017 if (ret == 0 && bytes_recvd > 0) { 1018 1019 request = (struct storvsc_cmd_request *) 1020 (unsigned long)request_id; 1021 1022 if ((request == &stor_device->init_request) || 1023 (request == &stor_device->reset_request)) { 1024 1025 memcpy(&request->vstor_packet, packet, 1026 sizeof(struct vstor_packet)); 1027 complete(&request->wait_event); 1028 } else { 1029 storvsc_on_receive(device, 1030 (struct vstor_packet *)packet, 1031 request); 1032 } 1033 } else { 1034 break; 1035 } 1036 } while (1); 1037 1038 return; 1039 } 1040 1041 static int storvsc_connect_to_vsp(struct hv_device *device, u32 ring_size) 1042 { 1043 struct vmstorage_channel_properties props; 1044 int ret; 1045 1046 memset(&props, 0, sizeof(struct vmstorage_channel_properties)); 1047 1048 ret = vmbus_open(device->channel, 1049 ring_size, 1050 ring_size, 1051 (void *)&props, 1052 sizeof(struct vmstorage_channel_properties), 1053 storvsc_on_channel_callback, device); 1054 1055 if (ret != 0) 1056 return ret; 1057 1058 ret = storvsc_channel_init(device); 1059 1060 return ret; 1061 } 1062 1063 static int storvsc_dev_remove(struct hv_device *device) 1064 { 1065 struct storvsc_device *stor_device; 1066 unsigned long flags; 1067 1068 stor_device = hv_get_drvdata(device); 1069 1070 spin_lock_irqsave(&device->channel->inbound_lock, flags); 1071 stor_device->destroy = true; 1072 spin_unlock_irqrestore(&device->channel->inbound_lock, flags); 1073 1074 /* 1075 * At this point, all outbound traffic should be disable. We 1076 * only allow inbound traffic (responses) to proceed so that 1077 * outstanding requests can be completed. 1078 */ 1079 1080 storvsc_wait_to_drain(stor_device); 1081 1082 /* 1083 * Since we have already drained, we don't need to busy wait 1084 * as was done in final_release_stor_device() 1085 * Note that we cannot set the ext pointer to NULL until 1086 * we have drained - to drain the outgoing packets, we need to 1087 * allow incoming packets. 1088 */ 1089 spin_lock_irqsave(&device->channel->inbound_lock, flags); 1090 hv_set_drvdata(device, NULL); 1091 spin_unlock_irqrestore(&device->channel->inbound_lock, flags); 1092 1093 /* Close the channel */ 1094 vmbus_close(device->channel); 1095 1096 kfree(stor_device); 1097 return 0; 1098 } 1099 1100 static int storvsc_do_io(struct hv_device *device, 1101 struct storvsc_cmd_request *request) 1102 { 1103 struct storvsc_device *stor_device; 1104 struct vstor_packet *vstor_packet; 1105 int ret = 0; 1106 1107 vstor_packet = &request->vstor_packet; 1108 stor_device = get_out_stor_device(device); 1109 1110 if (!stor_device) 1111 return -ENODEV; 1112 1113 1114 request->device = device; 1115 1116 1117 vstor_packet->flags |= REQUEST_COMPLETION_FLAG; 1118 1119 vstor_packet->vm_srb.length = sizeof(struct vmscsi_request); 1120 1121 1122 vstor_packet->vm_srb.sense_info_length = STORVSC_SENSE_BUFFER_SIZE; 1123 1124 1125 vstor_packet->vm_srb.data_transfer_length = 1126 request->data_buffer.len; 1127 1128 vstor_packet->operation = VSTOR_OPERATION_EXECUTE_SRB; 1129 1130 if (request->data_buffer.len) { 1131 ret = vmbus_sendpacket_multipagebuffer(device->channel, 1132 &request->data_buffer, 1133 vstor_packet, 1134 sizeof(struct vstor_packet), 1135 (unsigned long)request); 1136 } else { 1137 ret = vmbus_sendpacket(device->channel, vstor_packet, 1138 sizeof(struct vstor_packet), 1139 (unsigned long)request, 1140 VM_PKT_DATA_INBAND, 1141 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); 1142 } 1143 1144 if (ret != 0) 1145 return ret; 1146 1147 atomic_inc(&stor_device->num_outstanding_req); 1148 1149 return ret; 1150 } 1151 1152 static int storvsc_device_alloc(struct scsi_device *sdevice) 1153 { 1154 struct stor_mem_pools *memp; 1155 int number = STORVSC_MIN_BUF_NR; 1156 1157 memp = kzalloc(sizeof(struct stor_mem_pools), GFP_KERNEL); 1158 if (!memp) 1159 return -ENOMEM; 1160 1161 memp->request_pool = 1162 kmem_cache_create(dev_name(&sdevice->sdev_dev), 1163 sizeof(struct storvsc_cmd_request), 0, 1164 SLAB_HWCACHE_ALIGN, NULL); 1165 1166 if (!memp->request_pool) 1167 goto err0; 1168 1169 memp->request_mempool = mempool_create(number, mempool_alloc_slab, 1170 mempool_free_slab, 1171 memp->request_pool); 1172 1173 if (!memp->request_mempool) 1174 goto err1; 1175 1176 sdevice->hostdata = memp; 1177 1178 return 0; 1179 1180 err1: 1181 kmem_cache_destroy(memp->request_pool); 1182 1183 err0: 1184 kfree(memp); 1185 return -ENOMEM; 1186 } 1187 1188 static void storvsc_device_destroy(struct scsi_device *sdevice) 1189 { 1190 struct stor_mem_pools *memp = sdevice->hostdata; 1191 1192 mempool_destroy(memp->request_mempool); 1193 kmem_cache_destroy(memp->request_pool); 1194 kfree(memp); 1195 sdevice->hostdata = NULL; 1196 } 1197 1198 static int storvsc_device_configure(struct scsi_device *sdevice) 1199 { 1200 scsi_adjust_queue_depth(sdevice, MSG_SIMPLE_TAG, 1201 STORVSC_MAX_IO_REQUESTS); 1202 1203 blk_queue_max_segment_size(sdevice->request_queue, PAGE_SIZE); 1204 1205 blk_queue_bounce_limit(sdevice->request_queue, BLK_BOUNCE_ANY); 1206 1207 sdevice->no_write_same = 1; 1208 1209 return 0; 1210 } 1211 1212 static int storvsc_get_chs(struct scsi_device *sdev, struct block_device * bdev, 1213 sector_t capacity, int *info) 1214 { 1215 sector_t nsect = capacity; 1216 sector_t cylinders = nsect; 1217 int heads, sectors_pt; 1218 1219 /* 1220 * We are making up these values; let us keep it simple. 1221 */ 1222 heads = 0xff; 1223 sectors_pt = 0x3f; /* Sectors per track */ 1224 sector_div(cylinders, heads * sectors_pt); 1225 if ((sector_t)(cylinders + 1) * heads * sectors_pt < nsect) 1226 cylinders = 0xffff; 1227 1228 info[0] = heads; 1229 info[1] = sectors_pt; 1230 info[2] = (int)cylinders; 1231 1232 return 0; 1233 } 1234 1235 static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd) 1236 { 1237 struct hv_host_device *host_dev = shost_priv(scmnd->device->host); 1238 struct hv_device *device = host_dev->dev; 1239 1240 struct storvsc_device *stor_device; 1241 struct storvsc_cmd_request *request; 1242 struct vstor_packet *vstor_packet; 1243 int ret, t; 1244 1245 1246 stor_device = get_out_stor_device(device); 1247 if (!stor_device) 1248 return FAILED; 1249 1250 request = &stor_device->reset_request; 1251 vstor_packet = &request->vstor_packet; 1252 1253 init_completion(&request->wait_event); 1254 1255 vstor_packet->operation = VSTOR_OPERATION_RESET_BUS; 1256 vstor_packet->flags = REQUEST_COMPLETION_FLAG; 1257 vstor_packet->vm_srb.path_id = stor_device->path_id; 1258 1259 ret = vmbus_sendpacket(device->channel, vstor_packet, 1260 sizeof(struct vstor_packet), 1261 (unsigned long)&stor_device->reset_request, 1262 VM_PKT_DATA_INBAND, 1263 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED); 1264 if (ret != 0) 1265 return FAILED; 1266 1267 t = wait_for_completion_timeout(&request->wait_event, 5*HZ); 1268 if (t == 0) 1269 return TIMEOUT_ERROR; 1270 1271 1272 /* 1273 * At this point, all outstanding requests in the adapter 1274 * should have been flushed out and return to us 1275 * There is a potential race here where the host may be in 1276 * the process of responding when we return from here. 1277 * Just wait for all in-transit packets to be accounted for 1278 * before we return from here. 1279 */ 1280 storvsc_wait_to_drain(stor_device); 1281 1282 return SUCCESS; 1283 } 1284 1285 static bool storvsc_scsi_cmd_ok(struct scsi_cmnd *scmnd) 1286 { 1287 bool allowed = true; 1288 u8 scsi_op = scmnd->cmnd[0]; 1289 1290 switch (scsi_op) { 1291 /* the host does not handle WRITE_SAME, log accident usage */ 1292 case WRITE_SAME: 1293 /* 1294 * smartd sends this command and the host does not handle 1295 * this. So, don't send it. 1296 */ 1297 case SET_WINDOW: 1298 scmnd->result = ILLEGAL_REQUEST << 16; 1299 allowed = false; 1300 break; 1301 default: 1302 break; 1303 } 1304 return allowed; 1305 } 1306 1307 static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd) 1308 { 1309 int ret; 1310 struct hv_host_device *host_dev = shost_priv(host); 1311 struct hv_device *dev = host_dev->dev; 1312 struct storvsc_cmd_request *cmd_request; 1313 unsigned int request_size = 0; 1314 int i; 1315 struct scatterlist *sgl; 1316 unsigned int sg_count = 0; 1317 struct vmscsi_request *vm_srb; 1318 struct stor_mem_pools *memp = scmnd->device->hostdata; 1319 1320 if (!storvsc_scsi_cmd_ok(scmnd)) { 1321 scmnd->scsi_done(scmnd); 1322 return 0; 1323 } 1324 1325 request_size = sizeof(struct storvsc_cmd_request); 1326 1327 cmd_request = mempool_alloc(memp->request_mempool, 1328 GFP_ATOMIC); 1329 1330 /* 1331 * We might be invoked in an interrupt context; hence 1332 * mempool_alloc() can fail. 1333 */ 1334 if (!cmd_request) 1335 return SCSI_MLQUEUE_DEVICE_BUSY; 1336 1337 memset(cmd_request, 0, sizeof(struct storvsc_cmd_request)); 1338 1339 /* Setup the cmd request */ 1340 cmd_request->cmd = scmnd; 1341 1342 scmnd->host_scribble = (unsigned char *)cmd_request; 1343 1344 vm_srb = &cmd_request->vstor_packet.vm_srb; 1345 1346 1347 /* Build the SRB */ 1348 switch (scmnd->sc_data_direction) { 1349 case DMA_TO_DEVICE: 1350 vm_srb->data_in = WRITE_TYPE; 1351 break; 1352 case DMA_FROM_DEVICE: 1353 vm_srb->data_in = READ_TYPE; 1354 break; 1355 default: 1356 vm_srb->data_in = UNKNOWN_TYPE; 1357 break; 1358 } 1359 1360 1361 vm_srb->port_number = host_dev->port; 1362 vm_srb->path_id = scmnd->device->channel; 1363 vm_srb->target_id = scmnd->device->id; 1364 vm_srb->lun = scmnd->device->lun; 1365 1366 vm_srb->cdb_length = scmnd->cmd_len; 1367 1368 memcpy(vm_srb->cdb, scmnd->cmnd, vm_srb->cdb_length); 1369 1370 cmd_request->sense_buffer = scmnd->sense_buffer; 1371 1372 1373 cmd_request->data_buffer.len = scsi_bufflen(scmnd); 1374 if (scsi_sg_count(scmnd)) { 1375 sgl = (struct scatterlist *)scsi_sglist(scmnd); 1376 sg_count = scsi_sg_count(scmnd); 1377 1378 /* check if we need to bounce the sgl */ 1379 if (do_bounce_buffer(sgl, scsi_sg_count(scmnd)) != -1) { 1380 cmd_request->bounce_sgl = 1381 create_bounce_buffer(sgl, scsi_sg_count(scmnd), 1382 scsi_bufflen(scmnd), 1383 vm_srb->data_in); 1384 if (!cmd_request->bounce_sgl) { 1385 ret = SCSI_MLQUEUE_HOST_BUSY; 1386 goto queue_error; 1387 } 1388 1389 cmd_request->bounce_sgl_count = 1390 ALIGN(scsi_bufflen(scmnd), PAGE_SIZE) >> 1391 PAGE_SHIFT; 1392 1393 if (vm_srb->data_in == WRITE_TYPE) 1394 copy_to_bounce_buffer(sgl, 1395 cmd_request->bounce_sgl, 1396 scsi_sg_count(scmnd)); 1397 1398 sgl = cmd_request->bounce_sgl; 1399 sg_count = cmd_request->bounce_sgl_count; 1400 } 1401 1402 cmd_request->data_buffer.offset = sgl[0].offset; 1403 1404 for (i = 0; i < sg_count; i++) 1405 cmd_request->data_buffer.pfn_array[i] = 1406 page_to_pfn(sg_page((&sgl[i]))); 1407 1408 } else if (scsi_sglist(scmnd)) { 1409 cmd_request->data_buffer.offset = 1410 virt_to_phys(scsi_sglist(scmnd)) & (PAGE_SIZE-1); 1411 cmd_request->data_buffer.pfn_array[0] = 1412 virt_to_phys(scsi_sglist(scmnd)) >> PAGE_SHIFT; 1413 } 1414 1415 /* Invokes the vsc to start an IO */ 1416 ret = storvsc_do_io(dev, cmd_request); 1417 1418 if (ret == -EAGAIN) { 1419 /* no more space */ 1420 1421 if (cmd_request->bounce_sgl_count) { 1422 destroy_bounce_buffer(cmd_request->bounce_sgl, 1423 cmd_request->bounce_sgl_count); 1424 1425 ret = SCSI_MLQUEUE_DEVICE_BUSY; 1426 goto queue_error; 1427 } 1428 } 1429 1430 return 0; 1431 1432 queue_error: 1433 mempool_free(cmd_request, memp->request_mempool); 1434 scmnd->host_scribble = NULL; 1435 return ret; 1436 } 1437 1438 static struct scsi_host_template scsi_driver = { 1439 .module = THIS_MODULE, 1440 .name = "storvsc_host_t", 1441 .bios_param = storvsc_get_chs, 1442 .queuecommand = storvsc_queuecommand, 1443 .eh_host_reset_handler = storvsc_host_reset_handler, 1444 .slave_alloc = storvsc_device_alloc, 1445 .slave_destroy = storvsc_device_destroy, 1446 .slave_configure = storvsc_device_configure, 1447 .cmd_per_lun = 1, 1448 /* 64 max_queue * 1 target */ 1449 .can_queue = STORVSC_MAX_IO_REQUESTS*STORVSC_MAX_TARGETS, 1450 .this_id = -1, 1451 /* no use setting to 0 since ll_blk_rw reset it to 1 */ 1452 /* currently 32 */ 1453 .sg_tablesize = MAX_MULTIPAGE_BUFFER_COUNT, 1454 .use_clustering = DISABLE_CLUSTERING, 1455 /* Make sure we dont get a sg segment crosses a page boundary */ 1456 .dma_boundary = PAGE_SIZE-1, 1457 }; 1458 1459 enum { 1460 SCSI_GUID, 1461 IDE_GUID, 1462 }; 1463 1464 static const struct hv_vmbus_device_id id_table[] = { 1465 /* SCSI guid */ 1466 { HV_SCSI_GUID, 1467 .driver_data = SCSI_GUID 1468 }, 1469 /* IDE guid */ 1470 { HV_IDE_GUID, 1471 .driver_data = IDE_GUID 1472 }, 1473 { }, 1474 }; 1475 1476 MODULE_DEVICE_TABLE(vmbus, id_table); 1477 1478 static int storvsc_probe(struct hv_device *device, 1479 const struct hv_vmbus_device_id *dev_id) 1480 { 1481 int ret; 1482 struct Scsi_Host *host; 1483 struct hv_host_device *host_dev; 1484 bool dev_is_ide = ((dev_id->driver_data == IDE_GUID) ? true : false); 1485 int target = 0; 1486 struct storvsc_device *stor_device; 1487 1488 host = scsi_host_alloc(&scsi_driver, 1489 sizeof(struct hv_host_device)); 1490 if (!host) 1491 return -ENOMEM; 1492 1493 host_dev = shost_priv(host); 1494 memset(host_dev, 0, sizeof(struct hv_host_device)); 1495 1496 host_dev->port = host->host_no; 1497 host_dev->dev = device; 1498 1499 1500 stor_device = kzalloc(sizeof(struct storvsc_device), GFP_KERNEL); 1501 if (!stor_device) { 1502 ret = -ENOMEM; 1503 goto err_out0; 1504 } 1505 1506 stor_device->destroy = false; 1507 init_waitqueue_head(&stor_device->waiting_to_drain); 1508 stor_device->device = device; 1509 stor_device->host = host; 1510 hv_set_drvdata(device, stor_device); 1511 1512 stor_device->port_number = host->host_no; 1513 ret = storvsc_connect_to_vsp(device, storvsc_ringbuffer_size); 1514 if (ret) 1515 goto err_out1; 1516 1517 host_dev->path = stor_device->path_id; 1518 host_dev->target = stor_device->target_id; 1519 1520 /* max # of devices per target */ 1521 host->max_lun = STORVSC_MAX_LUNS_PER_TARGET; 1522 /* max # of targets per channel */ 1523 host->max_id = STORVSC_MAX_TARGETS; 1524 /* max # of channels */ 1525 host->max_channel = STORVSC_MAX_CHANNELS - 1; 1526 /* max cmd length */ 1527 host->max_cmd_len = STORVSC_MAX_CMD_LEN; 1528 1529 /* Register the HBA and start the scsi bus scan */ 1530 ret = scsi_add_host(host, &device->device); 1531 if (ret != 0) 1532 goto err_out2; 1533 1534 if (!dev_is_ide) { 1535 scsi_scan_host(host); 1536 } else { 1537 target = (device->dev_instance.b[5] << 8 | 1538 device->dev_instance.b[4]); 1539 ret = scsi_add_device(host, 0, target, 0); 1540 if (ret) { 1541 scsi_remove_host(host); 1542 goto err_out2; 1543 } 1544 } 1545 return 0; 1546 1547 err_out2: 1548 /* 1549 * Once we have connected with the host, we would need to 1550 * to invoke storvsc_dev_remove() to rollback this state and 1551 * this call also frees up the stor_device; hence the jump around 1552 * err_out1 label. 1553 */ 1554 storvsc_dev_remove(device); 1555 goto err_out0; 1556 1557 err_out1: 1558 kfree(stor_device); 1559 1560 err_out0: 1561 scsi_host_put(host); 1562 return ret; 1563 } 1564 1565 static int storvsc_remove(struct hv_device *dev) 1566 { 1567 struct storvsc_device *stor_device = hv_get_drvdata(dev); 1568 struct Scsi_Host *host = stor_device->host; 1569 1570 scsi_remove_host(host); 1571 storvsc_dev_remove(dev); 1572 scsi_host_put(host); 1573 1574 return 0; 1575 } 1576 1577 static struct hv_driver storvsc_drv = { 1578 .name = KBUILD_MODNAME, 1579 .id_table = id_table, 1580 .probe = storvsc_probe, 1581 .remove = storvsc_remove, 1582 }; 1583 1584 static int __init storvsc_drv_init(void) 1585 { 1586 u32 max_outstanding_req_per_channel; 1587 1588 /* 1589 * Divide the ring buffer data size (which is 1 page less 1590 * than the ring buffer size since that page is reserved for 1591 * the ring buffer indices) by the max request size (which is 1592 * vmbus_channel_packet_multipage_buffer + struct vstor_packet + u64) 1593 */ 1594 max_outstanding_req_per_channel = 1595 ((storvsc_ringbuffer_size - PAGE_SIZE) / 1596 ALIGN(MAX_MULTIPAGE_BUFFER_PACKET + 1597 sizeof(struct vstor_packet) + sizeof(u64), 1598 sizeof(u64))); 1599 1600 if (max_outstanding_req_per_channel < 1601 STORVSC_MAX_IO_REQUESTS) 1602 return -EINVAL; 1603 1604 return vmbus_driver_register(&storvsc_drv); 1605 } 1606 1607 static void __exit storvsc_drv_exit(void) 1608 { 1609 vmbus_driver_unregister(&storvsc_drv); 1610 } 1611 1612 MODULE_LICENSE("GPL"); 1613 MODULE_VERSION(HV_DRV_VERSION); 1614 MODULE_DESCRIPTION("Microsoft Hyper-V virtual storage driver"); 1615 module_init(storvsc_drv_init); 1616 module_exit(storvsc_drv_exit); 1617