2 * Copyright (c) 2009, Microsoft Corporation.
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.
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
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.
18 * Haiyang Zhang <haiyangz@microsoft.com>
19 * Hank Janssen <hjanssen@microsoft.com>
20 * K. Y. Srinivasan <kys@microsoft.com>
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>
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/blkdev.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>
46 * All wire protocol details (storage protocol between the guest and the host)
47 * are consolidated here.
49 * Begin protocol definitions.
55 * V1 RC < 2008/1/31: 1.0
56 * V1 RC > 2008/1/31: 2.0
62 #define VMSTOR_WIN7_MAJOR 4
63 #define VMSTOR_WIN7_MINOR 2
65 #define VMSTOR_WIN8_MAJOR 5
66 #define VMSTOR_WIN8_MINOR 1
69 /* Packet structure describing virtual storage requests. */
70 enum vstor_packet_operation {
71 VSTOR_OPERATION_COMPLETE_IO = 1,
72 VSTOR_OPERATION_REMOVE_DEVICE = 2,
73 VSTOR_OPERATION_EXECUTE_SRB = 3,
74 VSTOR_OPERATION_RESET_LUN = 4,
75 VSTOR_OPERATION_RESET_ADAPTER = 5,
76 VSTOR_OPERATION_RESET_BUS = 6,
77 VSTOR_OPERATION_BEGIN_INITIALIZATION = 7,
78 VSTOR_OPERATION_END_INITIALIZATION = 8,
79 VSTOR_OPERATION_QUERY_PROTOCOL_VERSION = 9,
80 VSTOR_OPERATION_QUERY_PROPERTIES = 10,
81 VSTOR_OPERATION_ENUMERATE_BUS = 11,
82 VSTOR_OPERATION_FCHBA_DATA = 12,
83 VSTOR_OPERATION_CREATE_SUB_CHANNELS = 13,
84 VSTOR_OPERATION_MAXIMUM = 13
88 * WWN packet for Fibre Channel HBA
91 struct hv_fc_wwn_packet {
95 u8 primary_port_wwn[8];
96 u8 primary_node_wwn[8];
97 u8 secondary_port_wwn[8];
98 u8 secondary_node_wwn[8];
107 #define SRB_FLAGS_QUEUE_ACTION_ENABLE 0x00000002
108 #define SRB_FLAGS_DISABLE_DISCONNECT 0x00000004
109 #define SRB_FLAGS_DISABLE_SYNCH_TRANSFER 0x00000008
110 #define SRB_FLAGS_BYPASS_FROZEN_QUEUE 0x00000010
111 #define SRB_FLAGS_DISABLE_AUTOSENSE 0x00000020
112 #define SRB_FLAGS_DATA_IN 0x00000040
113 #define SRB_FLAGS_DATA_OUT 0x00000080
114 #define SRB_FLAGS_NO_DATA_TRANSFER 0x00000000
115 #define SRB_FLAGS_UNSPECIFIED_DIRECTION (SRB_FLAGS_DATA_IN | SRB_FLAGS_DATA_OUT)
116 #define SRB_FLAGS_NO_QUEUE_FREEZE 0x00000100
117 #define SRB_FLAGS_ADAPTER_CACHE_ENABLE 0x00000200
118 #define SRB_FLAGS_FREE_SENSE_BUFFER 0x00000400
121 * This flag indicates the request is part of the workflow for processing a D3.
123 #define SRB_FLAGS_D3_PROCESSING 0x00000800
124 #define SRB_FLAGS_IS_ACTIVE 0x00010000
125 #define SRB_FLAGS_ALLOCATED_FROM_ZONE 0x00020000
126 #define SRB_FLAGS_SGLIST_FROM_POOL 0x00040000
127 #define SRB_FLAGS_BYPASS_LOCKED_QUEUE 0x00080000
128 #define SRB_FLAGS_NO_KEEP_AWAKE 0x00100000
129 #define SRB_FLAGS_PORT_DRIVER_ALLOCSENSE 0x00200000
130 #define SRB_FLAGS_PORT_DRIVER_SENSEHASPORT 0x00400000
131 #define SRB_FLAGS_DONT_START_NEXT_PACKET 0x00800000
132 #define SRB_FLAGS_PORT_DRIVER_RESERVED 0x0F000000
133 #define SRB_FLAGS_CLASS_DRIVER_RESERVED 0xF0000000
137 * Platform neutral description of a scsi request -
138 * this remains the same across the write regardless of 32/64 bit
139 * note: it's patterned off the SCSI_PASS_THROUGH structure
141 #define STORVSC_MAX_CMD_LEN 0x10
143 #define POST_WIN7_STORVSC_SENSE_BUFFER_SIZE 0x14
144 #define PRE_WIN8_STORVSC_SENSE_BUFFER_SIZE 0x12
146 #define STORVSC_SENSE_BUFFER_SIZE 0x14
147 #define STORVSC_MAX_BUF_LEN_WITH_PADDING 0x14
150 * Sense buffer size changed in win8; have a run-time
151 * variable to track the size we should use.
153 static int sense_buffer_size;
156 * The size of the vmscsi_request has changed in win8. The
157 * additional size is because of new elements added to the
158 * structure. These elements are valid only when we are talking
160 * Track the correction to size we need to apply.
163 static int vmscsi_size_delta;
164 static int vmstor_current_major;
165 static int vmstor_current_minor;
167 struct vmscsi_win8_extension {
169 * The following were added in Windows 8
179 struct vmscsi_request {
190 u8 sense_info_length;
194 u32 data_transfer_length;
197 u8 cdb[STORVSC_MAX_CMD_LEN];
198 u8 sense_data[STORVSC_SENSE_BUFFER_SIZE];
199 u8 reserved_array[STORVSC_MAX_BUF_LEN_WITH_PADDING];
202 * The following was added in win8.
204 struct vmscsi_win8_extension win8_extension;
206 } __attribute((packed));
210 * This structure is sent during the intialization phase to get the different
211 * properties of the channel.
214 #define STORAGE_CHANNEL_SUPPORTS_MULTI_CHANNEL 0x1
216 struct vmstorage_channel_properties {
222 u32 max_transfer_bytes;
227 /* This structure is sent during the storage protocol negotiations. */
228 struct vmstorage_protocol_version {
229 /* Major (MSW) and minor (LSW) version numbers. */
233 * Revision number is auto-incremented whenever this file is changed
234 * (See FILL_VMSTOR_REVISION macro above). Mismatch does not
235 * definitely indicate incompatibility--but it does indicate mismatched
237 * This is only used on the windows side. Just set it to 0.
242 /* Channel Property Flags */
243 #define STORAGE_CHANNEL_REMOVABLE_FLAG 0x1
244 #define STORAGE_CHANNEL_EMULATED_IDE_FLAG 0x2
246 struct vstor_packet {
247 /* Requested operation type */
248 enum vstor_packet_operation operation;
250 /* Flags - see below for values */
253 /* Status of the request returned from the server side. */
256 /* Data payload area */
259 * Structure used to forward SCSI commands from the
260 * client to the server.
262 struct vmscsi_request vm_srb;
264 /* Structure used to query channel properties. */
265 struct vmstorage_channel_properties storage_channel_properties;
267 /* Used during version negotiations. */
268 struct vmstorage_protocol_version version;
270 /* Fibre channel address packet */
271 struct hv_fc_wwn_packet wwn_packet;
273 /* Number of sub-channels to create */
274 u16 sub_channel_count;
276 /* This will be the maximum of the union members */
284 * This flag indicates that the server should send back a completion for this
288 #define REQUEST_COMPLETION_FLAG 0x1
290 /* Matches Windows-end */
291 enum storvsc_request_type {
298 * SRB status codes and masks; a subset of the codes used here.
301 #define SRB_STATUS_AUTOSENSE_VALID 0x80
302 #define SRB_STATUS_INVALID_LUN 0x20
303 #define SRB_STATUS_SUCCESS 0x01
304 #define SRB_STATUS_ABORTED 0x02
305 #define SRB_STATUS_ERROR 0x04
308 * This is the end of Protocol specific defines.
311 static int storvsc_ringbuffer_size = (256 * PAGE_SIZE);
312 static u32 max_outstanding_req_per_channel;
314 static int storvsc_vcpus_per_sub_channel = 4;
316 module_param(storvsc_ringbuffer_size, int, S_IRUGO);
317 MODULE_PARM_DESC(storvsc_ringbuffer_size, "Ring buffer size (bytes)");
319 module_param(storvsc_vcpus_per_sub_channel, int, S_IRUGO);
320 MODULE_PARM_DESC(vcpus_per_sub_channel, "Ratio of VCPUs to subchannels");
322 * Timeout in seconds for all devices managed by this driver.
324 static int storvsc_timeout = 180;
326 static int msft_blist_flags = BLIST_TRY_VPD_PAGES;
329 static void storvsc_on_channel_callback(void *context);
331 #define STORVSC_MAX_LUNS_PER_TARGET 255
332 #define STORVSC_MAX_TARGETS 2
333 #define STORVSC_MAX_CHANNELS 8
335 #define STORVSC_FC_MAX_LUNS_PER_TARGET 255
336 #define STORVSC_FC_MAX_TARGETS 128
337 #define STORVSC_FC_MAX_CHANNELS 8
339 #define STORVSC_IDE_MAX_LUNS_PER_TARGET 64
340 #define STORVSC_IDE_MAX_TARGETS 1
341 #define STORVSC_IDE_MAX_CHANNELS 1
343 struct storvsc_cmd_request {
344 struct scsi_cmnd *cmd;
346 unsigned int bounce_sgl_count;
347 struct scatterlist *bounce_sgl;
349 struct hv_device *device;
351 /* Synchronize the request/response if needed */
352 struct completion wait_event;
354 struct vmbus_channel_packet_multipage_buffer mpb;
355 struct vmbus_packet_mpb_array *payload;
358 struct vstor_packet vstor_packet;
362 /* A storvsc device is a device object that contains a vmbus channel */
363 struct storvsc_device {
364 struct hv_device *device;
368 bool open_sub_channel;
369 atomic_t num_outstanding_req;
370 struct Scsi_Host *host;
372 wait_queue_head_t waiting_to_drain;
375 * Each unique Port/Path/Target represents 1 channel ie scsi
376 * controller. In reality, the pathid, targetid is always 0
377 * and the port is set by us
379 unsigned int port_number;
380 unsigned char path_id;
381 unsigned char target_id;
384 * Max I/O, the device can support.
386 u32 max_transfer_bytes;
387 /* Used for vsc/vsp channel reset process */
388 struct storvsc_cmd_request init_request;
389 struct storvsc_cmd_request reset_request;
392 struct hv_host_device {
393 struct hv_device *dev;
396 unsigned char target;
399 struct storvsc_scan_work {
400 struct work_struct work;
401 struct Scsi_Host *host;
405 static void storvsc_device_scan(struct work_struct *work)
407 struct storvsc_scan_work *wrk;
409 struct scsi_device *sdev;
411 wrk = container_of(work, struct storvsc_scan_work, work);
414 sdev = scsi_device_lookup(wrk->host, 0, 0, lun);
417 scsi_rescan_device(&sdev->sdev_gendev);
418 scsi_device_put(sdev);
424 static void storvsc_host_scan(struct work_struct *work)
426 struct storvsc_scan_work *wrk;
427 struct Scsi_Host *host;
428 struct scsi_device *sdev;
430 wrk = container_of(work, struct storvsc_scan_work, work);
434 * Before scanning the host, first check to see if any of the
435 * currrently known devices have been hot removed. We issue a
436 * "unit ready" command against all currently known devices.
437 * This I/O will result in an error for devices that have been
438 * removed. As part of handling the I/O error, we remove the device.
440 * When a LUN is added or removed, the host sends us a signal to
441 * scan the host. Thus we are forced to discover the LUNs that
442 * may have been removed this way.
444 mutex_lock(&host->scan_mutex);
445 shost_for_each_device(sdev, host)
446 scsi_test_unit_ready(sdev, 1, 1, NULL);
447 mutex_unlock(&host->scan_mutex);
449 * Now scan the host to discover LUNs that may have been added.
451 scsi_scan_host(host);
456 static void storvsc_remove_lun(struct work_struct *work)
458 struct storvsc_scan_work *wrk;
459 struct scsi_device *sdev;
461 wrk = container_of(work, struct storvsc_scan_work, work);
462 if (!scsi_host_get(wrk->host))
465 sdev = scsi_device_lookup(wrk->host, 0, 0, wrk->lun);
468 scsi_remove_device(sdev);
469 scsi_device_put(sdev);
471 scsi_host_put(wrk->host);
478 * Major/minor macros. Minor version is in LSB, meaning that earlier flat
479 * version numbers will be interpreted as "0.x" (i.e., 1 becomes 0.1).
482 static inline u16 storvsc_get_version(u8 major, u8 minor)
486 version = ((major << 8) | minor);
491 * We can get incoming messages from the host that are not in response to
492 * messages that we have sent out. An example of this would be messages
493 * received by the guest to notify dynamic addition/removal of LUNs. To
494 * deal with potential race conditions where the driver may be in the
495 * midst of being unloaded when we might receive an unsolicited message
496 * from the host, we have implemented a mechanism to gurantee sequential
499 * 1) Once the device is marked as being destroyed, we will fail all
501 * 2) We permit incoming messages when the device is being destroyed,
502 * only to properly account for messages already sent out.
505 static inline struct storvsc_device *get_out_stor_device(
506 struct hv_device *device)
508 struct storvsc_device *stor_device;
510 stor_device = hv_get_drvdata(device);
512 if (stor_device && stor_device->destroy)
519 static inline void storvsc_wait_to_drain(struct storvsc_device *dev)
521 dev->drain_notify = true;
522 wait_event(dev->waiting_to_drain,
523 atomic_read(&dev->num_outstanding_req) == 0);
524 dev->drain_notify = false;
527 static inline struct storvsc_device *get_in_stor_device(
528 struct hv_device *device)
530 struct storvsc_device *stor_device;
532 stor_device = hv_get_drvdata(device);
538 * If the device is being destroyed; allow incoming
539 * traffic only to cleanup outstanding requests.
542 if (stor_device->destroy &&
543 (atomic_read(&stor_device->num_outstanding_req) == 0))
551 static void destroy_bounce_buffer(struct scatterlist *sgl,
552 unsigned int sg_count)
555 struct page *page_buf;
557 for (i = 0; i < sg_count; i++) {
558 page_buf = sg_page((&sgl[i]));
559 if (page_buf != NULL)
560 __free_page(page_buf);
566 static int do_bounce_buffer(struct scatterlist *sgl, unsigned int sg_count)
570 /* No need to check */
574 /* We have at least 2 sg entries */
575 for (i = 0; i < sg_count; i++) {
577 /* make sure 1st one does not have hole */
578 if (sgl[i].offset + sgl[i].length != PAGE_SIZE)
580 } else if (i == sg_count - 1) {
581 /* make sure last one does not have hole */
582 if (sgl[i].offset != 0)
585 /* make sure no hole in the middle */
586 if (sgl[i].length != PAGE_SIZE || sgl[i].offset != 0)
593 static struct scatterlist *create_bounce_buffer(struct scatterlist *sgl,
594 unsigned int sg_count,
600 struct scatterlist *bounce_sgl;
601 struct page *page_buf;
602 unsigned int buf_len = ((write == WRITE_TYPE) ? 0 : PAGE_SIZE);
604 num_pages = ALIGN(len, PAGE_SIZE) >> PAGE_SHIFT;
606 bounce_sgl = kcalloc(num_pages, sizeof(struct scatterlist), GFP_ATOMIC);
610 sg_init_table(bounce_sgl, num_pages);
611 for (i = 0; i < num_pages; i++) {
612 page_buf = alloc_page(GFP_ATOMIC);
615 sg_set_page(&bounce_sgl[i], page_buf, buf_len, 0);
621 destroy_bounce_buffer(bounce_sgl, num_pages);
625 /* Assume the original sgl has enough room */
626 static unsigned int copy_from_bounce_buffer(struct scatterlist *orig_sgl,
627 struct scatterlist *bounce_sgl,
628 unsigned int orig_sgl_count,
629 unsigned int bounce_sgl_count)
633 unsigned long src, dest;
634 unsigned int srclen, destlen, copylen;
635 unsigned int total_copied = 0;
636 unsigned long bounce_addr = 0;
637 unsigned long dest_addr = 0;
639 struct scatterlist *cur_dest_sgl;
640 struct scatterlist *cur_src_sgl;
642 local_irq_save(flags);
643 cur_dest_sgl = orig_sgl;
644 cur_src_sgl = bounce_sgl;
645 for (i = 0; i < orig_sgl_count; i++) {
646 dest_addr = (unsigned long)
647 kmap_atomic(sg_page(cur_dest_sgl)) +
648 cur_dest_sgl->offset;
650 destlen = cur_dest_sgl->length;
652 if (bounce_addr == 0)
653 bounce_addr = (unsigned long)kmap_atomic(
654 sg_page(cur_src_sgl));
657 src = bounce_addr + cur_src_sgl->offset;
658 srclen = cur_src_sgl->length - cur_src_sgl->offset;
660 copylen = min(srclen, destlen);
661 memcpy((void *)dest, (void *)src, copylen);
663 total_copied += copylen;
664 cur_src_sgl->offset += copylen;
668 if (cur_src_sgl->offset == cur_src_sgl->length) {
670 kunmap_atomic((void *)bounce_addr);
674 * It is possible that the number of elements
675 * in the bounce buffer may not be equal to
676 * the number of elements in the original
677 * scatter list. Handle this correctly.
680 if (j == bounce_sgl_count) {
682 * We are done; cleanup and return.
684 kunmap_atomic((void *)(dest_addr -
685 cur_dest_sgl->offset));
686 local_irq_restore(flags);
690 /* if we need to use another bounce buffer */
691 if (destlen || i != orig_sgl_count - 1) {
692 cur_src_sgl = sg_next(cur_src_sgl);
693 bounce_addr = (unsigned long)
695 sg_page(cur_src_sgl));
697 } else if (destlen == 0 && i == orig_sgl_count - 1) {
698 /* unmap the last bounce that is < PAGE_SIZE */
699 kunmap_atomic((void *)bounce_addr);
703 kunmap_atomic((void *)(dest_addr - cur_dest_sgl->offset));
704 cur_dest_sgl = sg_next(cur_dest_sgl);
707 local_irq_restore(flags);
712 /* Assume the bounce_sgl has enough room ie using the create_bounce_buffer() */
713 static unsigned int copy_to_bounce_buffer(struct scatterlist *orig_sgl,
714 struct scatterlist *bounce_sgl,
715 unsigned int orig_sgl_count)
719 unsigned long src, dest;
720 unsigned int srclen, destlen, copylen;
721 unsigned int total_copied = 0;
722 unsigned long bounce_addr = 0;
723 unsigned long src_addr = 0;
725 struct scatterlist *cur_src_sgl;
726 struct scatterlist *cur_dest_sgl;
728 local_irq_save(flags);
730 cur_src_sgl = orig_sgl;
731 cur_dest_sgl = bounce_sgl;
733 for (i = 0; i < orig_sgl_count; i++) {
734 src_addr = (unsigned long)
735 kmap_atomic(sg_page(cur_src_sgl)) +
738 srclen = cur_src_sgl->length;
740 if (bounce_addr == 0)
741 bounce_addr = (unsigned long)
742 kmap_atomic(sg_page(cur_dest_sgl));
745 /* assume bounce offset always == 0 */
746 dest = bounce_addr + cur_dest_sgl->length;
747 destlen = PAGE_SIZE - cur_dest_sgl->length;
749 copylen = min(srclen, destlen);
750 memcpy((void *)dest, (void *)src, copylen);
752 total_copied += copylen;
753 cur_dest_sgl->length += copylen;
757 if (cur_dest_sgl->length == PAGE_SIZE) {
758 /* full..move to next entry */
759 kunmap_atomic((void *)bounce_addr);
764 /* if we need to use another bounce buffer */
765 if (srclen && bounce_addr == 0) {
766 cur_dest_sgl = sg_next(cur_dest_sgl);
767 bounce_addr = (unsigned long)
769 sg_page(cur_dest_sgl));
774 kunmap_atomic((void *)(src_addr - cur_src_sgl->offset));
775 cur_src_sgl = sg_next(cur_src_sgl);
779 kunmap_atomic((void *)bounce_addr);
781 local_irq_restore(flags);
786 static void handle_sc_creation(struct vmbus_channel *new_sc)
788 struct hv_device *device = new_sc->primary_channel->device_obj;
789 struct storvsc_device *stor_device;
790 struct vmstorage_channel_properties props;
792 stor_device = get_out_stor_device(device);
796 if (stor_device->open_sub_channel == false)
799 memset(&props, 0, sizeof(struct vmstorage_channel_properties));
802 storvsc_ringbuffer_size,
803 storvsc_ringbuffer_size,
805 sizeof(struct vmstorage_channel_properties),
806 storvsc_on_channel_callback, new_sc);
809 static void handle_multichannel_storage(struct hv_device *device, int max_chns)
811 struct storvsc_device *stor_device;
812 int num_cpus = num_online_cpus();
814 struct storvsc_cmd_request *request;
815 struct vstor_packet *vstor_packet;
818 num_sc = ((max_chns > num_cpus) ? num_cpus : max_chns);
819 stor_device = get_out_stor_device(device);
823 request = &stor_device->init_request;
824 vstor_packet = &request->vstor_packet;
826 stor_device->open_sub_channel = true;
828 * Establish a handler for dealing with subchannels.
830 vmbus_set_sc_create_callback(device->channel, handle_sc_creation);
833 * Check to see if sub-channels have already been created. This
834 * can happen when this driver is re-loaded after unloading.
837 if (vmbus_are_subchannels_present(device->channel))
840 stor_device->open_sub_channel = false;
842 * Request the host to create sub-channels.
844 memset(request, 0, sizeof(struct storvsc_cmd_request));
845 init_completion(&request->wait_event);
846 vstor_packet->operation = VSTOR_OPERATION_CREATE_SUB_CHANNELS;
847 vstor_packet->flags = REQUEST_COMPLETION_FLAG;
848 vstor_packet->sub_channel_count = num_sc;
850 ret = vmbus_sendpacket(device->channel, vstor_packet,
851 (sizeof(struct vstor_packet) -
853 (unsigned long)request,
855 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
860 t = wait_for_completion_timeout(&request->wait_event, 10*HZ);
864 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
865 vstor_packet->status != 0)
869 * Now that we created the sub-channels, invoke the check; this
870 * may trigger the callback.
872 stor_device->open_sub_channel = true;
873 vmbus_are_subchannels_present(device->channel);
876 static int storvsc_channel_init(struct hv_device *device)
878 struct storvsc_device *stor_device;
879 struct storvsc_cmd_request *request;
880 struct vstor_packet *vstor_packet;
883 bool process_sub_channels = false;
885 stor_device = get_out_stor_device(device);
889 request = &stor_device->init_request;
890 vstor_packet = &request->vstor_packet;
893 * Now, initiate the vsc/vsp initialization protocol on the open
896 memset(request, 0, sizeof(struct storvsc_cmd_request));
897 init_completion(&request->wait_event);
898 vstor_packet->operation = VSTOR_OPERATION_BEGIN_INITIALIZATION;
899 vstor_packet->flags = REQUEST_COMPLETION_FLAG;
901 ret = vmbus_sendpacket(device->channel, vstor_packet,
902 (sizeof(struct vstor_packet) -
904 (unsigned long)request,
906 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
910 t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
916 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
917 vstor_packet->status != 0)
921 /* reuse the packet for version range supported */
922 memset(vstor_packet, 0, sizeof(struct vstor_packet));
923 vstor_packet->operation = VSTOR_OPERATION_QUERY_PROTOCOL_VERSION;
924 vstor_packet->flags = REQUEST_COMPLETION_FLAG;
926 vstor_packet->version.major_minor =
927 storvsc_get_version(vmstor_current_major, vmstor_current_minor);
930 * The revision number is only used in Windows; set it to 0.
932 vstor_packet->version.revision = 0;
934 ret = vmbus_sendpacket(device->channel, vstor_packet,
935 (sizeof(struct vstor_packet) -
937 (unsigned long)request,
939 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
943 t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
949 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
950 vstor_packet->status != 0)
954 memset(vstor_packet, 0, sizeof(struct vstor_packet));
955 vstor_packet->operation = VSTOR_OPERATION_QUERY_PROPERTIES;
956 vstor_packet->flags = REQUEST_COMPLETION_FLAG;
958 ret = vmbus_sendpacket(device->channel, vstor_packet,
959 (sizeof(struct vstor_packet) -
961 (unsigned long)request,
963 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
968 t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
974 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
975 vstor_packet->status != 0)
979 * Check to see if multi-channel support is there.
980 * Hosts that implement protocol version of 5.1 and above
981 * support multi-channel.
983 max_chns = vstor_packet->storage_channel_properties.max_channel_cnt;
984 if (vmbus_proto_version >= VERSION_WIN8) {
985 if (vstor_packet->storage_channel_properties.flags &
986 STORAGE_CHANNEL_SUPPORTS_MULTI_CHANNEL)
987 process_sub_channels = true;
989 stor_device->max_transfer_bytes =
990 vstor_packet->storage_channel_properties.max_transfer_bytes;
992 memset(vstor_packet, 0, sizeof(struct vstor_packet));
993 vstor_packet->operation = VSTOR_OPERATION_END_INITIALIZATION;
994 vstor_packet->flags = REQUEST_COMPLETION_FLAG;
996 ret = vmbus_sendpacket(device->channel, vstor_packet,
997 (sizeof(struct vstor_packet) -
999 (unsigned long)request,
1001 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
1006 t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
1012 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
1013 vstor_packet->status != 0)
1016 if (process_sub_channels)
1017 handle_multichannel_storage(device, max_chns);
1024 static void storvsc_handle_error(struct vmscsi_request *vm_srb,
1025 struct scsi_cmnd *scmnd,
1026 struct Scsi_Host *host,
1029 struct storvsc_scan_work *wrk;
1030 void (*process_err_fn)(struct work_struct *work);
1031 bool do_work = false;
1033 switch (vm_srb->srb_status) {
1034 case SRB_STATUS_ERROR:
1036 * If there is an error; offline the device since all
1037 * error recovery strategies would have already been
1038 * deployed on the host side. However, if the command
1039 * were a pass-through command deal with it appropriately.
1041 switch (scmnd->cmnd[0]) {
1044 set_host_byte(scmnd, DID_PASSTHROUGH);
1047 * On Some Windows hosts TEST_UNIT_READY command can return
1048 * SRB_STATUS_ERROR, let the upper level code deal with it
1049 * based on the sense information.
1051 case TEST_UNIT_READY:
1054 set_host_byte(scmnd, DID_TARGET_FAILURE);
1057 case SRB_STATUS_INVALID_LUN:
1059 process_err_fn = storvsc_remove_lun;
1061 case (SRB_STATUS_ABORTED | SRB_STATUS_AUTOSENSE_VALID):
1062 if ((asc == 0x2a) && (ascq == 0x9)) {
1064 process_err_fn = storvsc_device_scan;
1066 * Retry the I/O that trigerred this.
1068 set_host_byte(scmnd, DID_REQUEUE);
1077 * We need to schedule work to process this error; schedule it.
1079 wrk = kmalloc(sizeof(struct storvsc_scan_work), GFP_ATOMIC);
1081 set_host_byte(scmnd, DID_TARGET_FAILURE);
1086 wrk->lun = vm_srb->lun;
1087 INIT_WORK(&wrk->work, process_err_fn);
1088 schedule_work(&wrk->work);
1092 static void storvsc_command_completion(struct storvsc_cmd_request *cmd_request)
1094 struct scsi_cmnd *scmnd = cmd_request->cmd;
1095 struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
1096 struct scsi_sense_hdr sense_hdr;
1097 struct vmscsi_request *vm_srb;
1098 struct Scsi_Host *host;
1099 struct storvsc_device *stor_dev;
1100 struct hv_device *dev = host_dev->dev;
1101 u32 payload_sz = cmd_request->payload_sz;
1102 void *payload = cmd_request->payload;
1104 stor_dev = get_in_stor_device(dev);
1105 host = stor_dev->host;
1107 vm_srb = &cmd_request->vstor_packet.vm_srb;
1108 if (cmd_request->bounce_sgl_count) {
1109 if (vm_srb->data_in == READ_TYPE)
1110 copy_from_bounce_buffer(scsi_sglist(scmnd),
1111 cmd_request->bounce_sgl,
1112 scsi_sg_count(scmnd),
1113 cmd_request->bounce_sgl_count);
1114 destroy_bounce_buffer(cmd_request->bounce_sgl,
1115 cmd_request->bounce_sgl_count);
1118 scmnd->result = vm_srb->scsi_status;
1120 if (scmnd->result) {
1121 if (scsi_normalize_sense(scmnd->sense_buffer,
1122 SCSI_SENSE_BUFFERSIZE, &sense_hdr))
1123 scsi_print_sense_hdr(scmnd->device, "storvsc",
1127 if (vm_srb->srb_status != SRB_STATUS_SUCCESS)
1128 storvsc_handle_error(vm_srb, scmnd, host, sense_hdr.asc,
1131 scsi_set_resid(scmnd,
1132 cmd_request->payload->range.len -
1133 vm_srb->data_transfer_length);
1135 scmnd->scsi_done(scmnd);
1138 sizeof(struct vmbus_channel_packet_multipage_buffer))
1142 static void storvsc_on_io_completion(struct hv_device *device,
1143 struct vstor_packet *vstor_packet,
1144 struct storvsc_cmd_request *request)
1146 struct storvsc_device *stor_device;
1147 struct vstor_packet *stor_pkt;
1149 stor_device = hv_get_drvdata(device);
1150 stor_pkt = &request->vstor_packet;
1153 * The current SCSI handling on the host side does
1154 * not correctly handle:
1155 * INQUIRY command with page code parameter set to 0x80
1156 * MODE_SENSE command with cmd[2] == 0x1c
1158 * Setup srb and scsi status so this won't be fatal.
1159 * We do this so we can distinguish truly fatal failues
1160 * (srb status == 0x4) and off-line the device in that case.
1163 if ((stor_pkt->vm_srb.cdb[0] == INQUIRY) ||
1164 (stor_pkt->vm_srb.cdb[0] == MODE_SENSE)) {
1165 vstor_packet->vm_srb.scsi_status = 0;
1166 vstor_packet->vm_srb.srb_status = SRB_STATUS_SUCCESS;
1170 /* Copy over the status...etc */
1171 stor_pkt->vm_srb.scsi_status = vstor_packet->vm_srb.scsi_status;
1172 stor_pkt->vm_srb.srb_status = vstor_packet->vm_srb.srb_status;
1173 stor_pkt->vm_srb.sense_info_length =
1174 vstor_packet->vm_srb.sense_info_length;
1177 if ((vstor_packet->vm_srb.scsi_status & 0xFF) == 0x02) {
1178 /* CHECK_CONDITION */
1179 if (vstor_packet->vm_srb.srb_status &
1180 SRB_STATUS_AUTOSENSE_VALID) {
1181 /* autosense data available */
1183 memcpy(request->cmd->sense_buffer,
1184 vstor_packet->vm_srb.sense_data,
1185 vstor_packet->vm_srb.sense_info_length);
1190 stor_pkt->vm_srb.data_transfer_length =
1191 vstor_packet->vm_srb.data_transfer_length;
1193 storvsc_command_completion(request);
1195 if (atomic_dec_and_test(&stor_device->num_outstanding_req) &&
1196 stor_device->drain_notify)
1197 wake_up(&stor_device->waiting_to_drain);
1202 static void storvsc_on_receive(struct hv_device *device,
1203 struct vstor_packet *vstor_packet,
1204 struct storvsc_cmd_request *request)
1206 struct storvsc_scan_work *work;
1207 struct storvsc_device *stor_device;
1209 switch (vstor_packet->operation) {
1210 case VSTOR_OPERATION_COMPLETE_IO:
1211 storvsc_on_io_completion(device, vstor_packet, request);
1214 case VSTOR_OPERATION_REMOVE_DEVICE:
1215 case VSTOR_OPERATION_ENUMERATE_BUS:
1216 stor_device = get_in_stor_device(device);
1217 work = kmalloc(sizeof(struct storvsc_scan_work), GFP_ATOMIC);
1221 INIT_WORK(&work->work, storvsc_host_scan);
1222 work->host = stor_device->host;
1223 schedule_work(&work->work);
1231 static void storvsc_on_channel_callback(void *context)
1233 struct vmbus_channel *channel = (struct vmbus_channel *)context;
1234 struct hv_device *device;
1235 struct storvsc_device *stor_device;
1238 unsigned char packet[ALIGN(sizeof(struct vstor_packet), 8)];
1239 struct storvsc_cmd_request *request;
1242 if (channel->primary_channel != NULL)
1243 device = channel->primary_channel->device_obj;
1245 device = channel->device_obj;
1247 stor_device = get_in_stor_device(device);
1252 ret = vmbus_recvpacket(channel, packet,
1253 ALIGN((sizeof(struct vstor_packet) -
1254 vmscsi_size_delta), 8),
1255 &bytes_recvd, &request_id);
1256 if (ret == 0 && bytes_recvd > 0) {
1258 request = (struct storvsc_cmd_request *)
1259 (unsigned long)request_id;
1261 if ((request == &stor_device->init_request) ||
1262 (request == &stor_device->reset_request)) {
1264 memcpy(&request->vstor_packet, packet,
1265 (sizeof(struct vstor_packet) -
1266 vmscsi_size_delta));
1267 complete(&request->wait_event);
1269 storvsc_on_receive(device,
1270 (struct vstor_packet *)packet,
1281 static int storvsc_connect_to_vsp(struct hv_device *device, u32 ring_size)
1283 struct vmstorage_channel_properties props;
1286 memset(&props, 0, sizeof(struct vmstorage_channel_properties));
1288 ret = vmbus_open(device->channel,
1292 sizeof(struct vmstorage_channel_properties),
1293 storvsc_on_channel_callback, device->channel);
1298 ret = storvsc_channel_init(device);
1303 static int storvsc_dev_remove(struct hv_device *device)
1305 struct storvsc_device *stor_device;
1306 unsigned long flags;
1308 stor_device = hv_get_drvdata(device);
1310 spin_lock_irqsave(&device->channel->inbound_lock, flags);
1311 stor_device->destroy = true;
1312 spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
1315 * At this point, all outbound traffic should be disable. We
1316 * only allow inbound traffic (responses) to proceed so that
1317 * outstanding requests can be completed.
1320 storvsc_wait_to_drain(stor_device);
1323 * Since we have already drained, we don't need to busy wait
1324 * as was done in final_release_stor_device()
1325 * Note that we cannot set the ext pointer to NULL until
1326 * we have drained - to drain the outgoing packets, we need to
1327 * allow incoming packets.
1329 spin_lock_irqsave(&device->channel->inbound_lock, flags);
1330 hv_set_drvdata(device, NULL);
1331 spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
1333 /* Close the channel */
1334 vmbus_close(device->channel);
1340 static int storvsc_do_io(struct hv_device *device,
1341 struct storvsc_cmd_request *request)
1343 struct storvsc_device *stor_device;
1344 struct vstor_packet *vstor_packet;
1345 struct vmbus_channel *outgoing_channel;
1348 vstor_packet = &request->vstor_packet;
1349 stor_device = get_out_stor_device(device);
1355 request->device = device;
1357 * Select an an appropriate channel to send the request out.
1360 outgoing_channel = vmbus_get_outgoing_channel(device->channel);
1363 vstor_packet->flags |= REQUEST_COMPLETION_FLAG;
1365 vstor_packet->vm_srb.length = (sizeof(struct vmscsi_request) -
1369 vstor_packet->vm_srb.sense_info_length = sense_buffer_size;
1372 vstor_packet->vm_srb.data_transfer_length =
1373 request->payload->range.len;
1375 vstor_packet->operation = VSTOR_OPERATION_EXECUTE_SRB;
1377 if (request->payload->range.len) {
1379 ret = vmbus_sendpacket_mpb_desc(outgoing_channel,
1380 request->payload, request->payload_sz,
1382 (sizeof(struct vstor_packet) -
1384 (unsigned long)request);
1386 ret = vmbus_sendpacket(outgoing_channel, vstor_packet,
1387 (sizeof(struct vstor_packet) -
1389 (unsigned long)request,
1391 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
1397 atomic_inc(&stor_device->num_outstanding_req);
1402 static int storvsc_device_configure(struct scsi_device *sdevice)
1405 blk_queue_max_segment_size(sdevice->request_queue, PAGE_SIZE);
1407 blk_queue_bounce_limit(sdevice->request_queue, BLK_BOUNCE_ANY);
1409 blk_queue_rq_timeout(sdevice->request_queue, (storvsc_timeout * HZ));
1411 sdevice->no_write_same = 1;
1414 * Add blist flags to permit the reading of the VPD pages even when
1415 * the target may claim SPC-2 compliance. MSFT targets currently
1416 * claim SPC-2 compliance while they implement post SPC-2 features.
1417 * With this patch we can correctly handle WRITE_SAME_16 issues.
1419 sdevice->sdev_bflags |= msft_blist_flags;
1422 * If the host is WIN8 or WIN8 R2, claim conformance to SPC-3
1423 * if the device is a MSFT virtual device.
1425 if (!strncmp(sdevice->vendor, "Msft", 4)) {
1426 switch (vmbus_proto_version) {
1428 case VERSION_WIN8_1:
1429 sdevice->scsi_level = SCSI_SPC_3;
1437 static int storvsc_get_chs(struct scsi_device *sdev, struct block_device * bdev,
1438 sector_t capacity, int *info)
1440 sector_t nsect = capacity;
1441 sector_t cylinders = nsect;
1442 int heads, sectors_pt;
1445 * We are making up these values; let us keep it simple.
1448 sectors_pt = 0x3f; /* Sectors per track */
1449 sector_div(cylinders, heads * sectors_pt);
1450 if ((sector_t)(cylinders + 1) * heads * sectors_pt < nsect)
1454 info[1] = sectors_pt;
1455 info[2] = (int)cylinders;
1460 static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd)
1462 struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
1463 struct hv_device *device = host_dev->dev;
1465 struct storvsc_device *stor_device;
1466 struct storvsc_cmd_request *request;
1467 struct vstor_packet *vstor_packet;
1471 stor_device = get_out_stor_device(device);
1475 request = &stor_device->reset_request;
1476 vstor_packet = &request->vstor_packet;
1478 init_completion(&request->wait_event);
1480 vstor_packet->operation = VSTOR_OPERATION_RESET_BUS;
1481 vstor_packet->flags = REQUEST_COMPLETION_FLAG;
1482 vstor_packet->vm_srb.path_id = stor_device->path_id;
1484 ret = vmbus_sendpacket(device->channel, vstor_packet,
1485 (sizeof(struct vstor_packet) -
1487 (unsigned long)&stor_device->reset_request,
1489 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
1493 t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
1495 return TIMEOUT_ERROR;
1499 * At this point, all outstanding requests in the adapter
1500 * should have been flushed out and return to us
1501 * There is a potential race here where the host may be in
1502 * the process of responding when we return from here.
1503 * Just wait for all in-transit packets to be accounted for
1504 * before we return from here.
1506 storvsc_wait_to_drain(stor_device);
1512 * The host guarantees to respond to each command, although I/O latencies might
1513 * be unbounded on Azure. Reset the timer unconditionally to give the host a
1514 * chance to perform EH.
1516 static enum blk_eh_timer_return storvsc_eh_timed_out(struct scsi_cmnd *scmnd)
1518 return BLK_EH_RESET_TIMER;
1521 static bool storvsc_scsi_cmd_ok(struct scsi_cmnd *scmnd)
1523 bool allowed = true;
1524 u8 scsi_op = scmnd->cmnd[0];
1527 /* the host does not handle WRITE_SAME, log accident usage */
1530 * smartd sends this command and the host does not handle
1531 * this. So, don't send it.
1534 scmnd->result = ILLEGAL_REQUEST << 16;
1543 static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
1546 struct hv_host_device *host_dev = shost_priv(host);
1547 struct hv_device *dev = host_dev->dev;
1548 struct storvsc_cmd_request *cmd_request = scsi_cmd_priv(scmnd);
1550 struct scatterlist *sgl;
1551 unsigned int sg_count = 0;
1552 struct vmscsi_request *vm_srb;
1553 struct scatterlist *cur_sgl;
1554 struct vmbus_packet_mpb_array *payload;
1558 if (vmstor_current_major <= VMSTOR_WIN8_MAJOR) {
1560 * On legacy hosts filter unimplemented commands.
1561 * Future hosts are expected to correctly handle
1562 * unsupported commands. Furthermore, it is
1563 * possible that some of the currently
1564 * unsupported commands maybe supported in
1565 * future versions of the host.
1567 if (!storvsc_scsi_cmd_ok(scmnd)) {
1568 scmnd->scsi_done(scmnd);
1573 /* Setup the cmd request */
1574 cmd_request->cmd = scmnd;
1576 vm_srb = &cmd_request->vstor_packet.vm_srb;
1577 vm_srb->win8_extension.time_out_value = 60;
1579 vm_srb->win8_extension.srb_flags |=
1580 (SRB_FLAGS_QUEUE_ACTION_ENABLE |
1581 SRB_FLAGS_DISABLE_SYNCH_TRANSFER);
1584 switch (scmnd->sc_data_direction) {
1586 vm_srb->data_in = WRITE_TYPE;
1587 vm_srb->win8_extension.srb_flags |= SRB_FLAGS_DATA_OUT;
1589 case DMA_FROM_DEVICE:
1590 vm_srb->data_in = READ_TYPE;
1591 vm_srb->win8_extension.srb_flags |= SRB_FLAGS_DATA_IN;
1594 vm_srb->data_in = UNKNOWN_TYPE;
1595 vm_srb->win8_extension.srb_flags |= SRB_FLAGS_NO_DATA_TRANSFER;
1599 * This is DMA_BIDIRECTIONAL or something else we are never
1600 * supposed to see here.
1602 WARN(1, "Unexpected data direction: %d\n",
1603 scmnd->sc_data_direction);
1608 vm_srb->port_number = host_dev->port;
1609 vm_srb->path_id = scmnd->device->channel;
1610 vm_srb->target_id = scmnd->device->id;
1611 vm_srb->lun = scmnd->device->lun;
1613 vm_srb->cdb_length = scmnd->cmd_len;
1615 memcpy(vm_srb->cdb, scmnd->cmnd, vm_srb->cdb_length);
1617 sgl = (struct scatterlist *)scsi_sglist(scmnd);
1618 sg_count = scsi_sg_count(scmnd);
1620 length = scsi_bufflen(scmnd);
1621 payload = (struct vmbus_packet_mpb_array *)&cmd_request->mpb;
1622 payload_sz = sizeof(cmd_request->mpb);
1625 /* check if we need to bounce the sgl */
1626 if (do_bounce_buffer(sgl, scsi_sg_count(scmnd)) != -1) {
1627 cmd_request->bounce_sgl =
1628 create_bounce_buffer(sgl, sg_count,
1631 if (!cmd_request->bounce_sgl)
1632 return SCSI_MLQUEUE_HOST_BUSY;
1634 cmd_request->bounce_sgl_count =
1635 ALIGN(length, PAGE_SIZE) >> PAGE_SHIFT;
1637 if (vm_srb->data_in == WRITE_TYPE)
1638 copy_to_bounce_buffer(sgl,
1639 cmd_request->bounce_sgl, sg_count);
1641 sgl = cmd_request->bounce_sgl;
1642 sg_count = cmd_request->bounce_sgl_count;
1646 if (sg_count > MAX_PAGE_BUFFER_COUNT) {
1648 payload_sz = (sg_count * sizeof(void *) +
1649 sizeof(struct vmbus_packet_mpb_array));
1650 payload = kmalloc(payload_sz, GFP_ATOMIC);
1652 if (cmd_request->bounce_sgl_count)
1653 destroy_bounce_buffer(
1654 cmd_request->bounce_sgl,
1655 cmd_request->bounce_sgl_count);
1657 return SCSI_MLQUEUE_DEVICE_BUSY;
1661 payload->range.len = length;
1662 payload->range.offset = sgl[0].offset;
1665 for (i = 0; i < sg_count; i++) {
1666 payload->range.pfn_array[i] =
1667 page_to_pfn(sg_page((cur_sgl)));
1668 cur_sgl = sg_next(cur_sgl);
1671 } else if (scsi_sglist(scmnd)) {
1672 payload->range.len = length;
1673 payload->range.offset =
1674 virt_to_phys(scsi_sglist(scmnd)) & (PAGE_SIZE-1);
1675 payload->range.pfn_array[0] =
1676 virt_to_phys(scsi_sglist(scmnd)) >> PAGE_SHIFT;
1679 cmd_request->payload = payload;
1680 cmd_request->payload_sz = payload_sz;
1682 /* Invokes the vsc to start an IO */
1683 ret = storvsc_do_io(dev, cmd_request);
1685 if (ret == -EAGAIN) {
1688 if (cmd_request->bounce_sgl_count)
1689 destroy_bounce_buffer(cmd_request->bounce_sgl,
1690 cmd_request->bounce_sgl_count);
1692 return SCSI_MLQUEUE_DEVICE_BUSY;
1698 static struct scsi_host_template scsi_driver = {
1699 .module = THIS_MODULE,
1700 .name = "storvsc_host_t",
1701 .cmd_size = sizeof(struct storvsc_cmd_request),
1702 .bios_param = storvsc_get_chs,
1703 .queuecommand = storvsc_queuecommand,
1704 .eh_host_reset_handler = storvsc_host_reset_handler,
1705 .proc_name = "storvsc_host",
1706 .eh_timed_out = storvsc_eh_timed_out,
1707 .slave_configure = storvsc_device_configure,
1710 .use_clustering = ENABLE_CLUSTERING,
1711 /* Make sure we dont get a sg segment crosses a page boundary */
1712 .dma_boundary = PAGE_SIZE-1,
1722 static const struct hv_vmbus_device_id id_table[] = {
1725 .driver_data = SCSI_GUID
1729 .driver_data = IDE_GUID
1731 /* Fibre Channel GUID */
1734 .driver_data = SFC_GUID
1739 MODULE_DEVICE_TABLE(vmbus, id_table);
1741 static int storvsc_probe(struct hv_device *device,
1742 const struct hv_vmbus_device_id *dev_id)
1745 int num_cpus = num_online_cpus();
1746 struct Scsi_Host *host;
1747 struct hv_host_device *host_dev;
1748 bool dev_is_ide = ((dev_id->driver_data == IDE_GUID) ? true : false);
1750 struct storvsc_device *stor_device;
1751 int max_luns_per_target;
1754 int max_sub_channels = 0;
1757 * Based on the windows host we are running on,
1758 * set state to properly communicate with the host.
1761 if (vmbus_proto_version < VERSION_WIN8) {
1762 sense_buffer_size = PRE_WIN8_STORVSC_SENSE_BUFFER_SIZE;
1763 vmscsi_size_delta = sizeof(struct vmscsi_win8_extension);
1764 vmstor_current_major = VMSTOR_WIN7_MAJOR;
1765 vmstor_current_minor = VMSTOR_WIN7_MINOR;
1766 max_luns_per_target = STORVSC_IDE_MAX_LUNS_PER_TARGET;
1767 max_targets = STORVSC_IDE_MAX_TARGETS;
1768 max_channels = STORVSC_IDE_MAX_CHANNELS;
1770 sense_buffer_size = POST_WIN7_STORVSC_SENSE_BUFFER_SIZE;
1771 vmscsi_size_delta = 0;
1772 vmstor_current_major = VMSTOR_WIN8_MAJOR;
1773 vmstor_current_minor = VMSTOR_WIN8_MINOR;
1774 max_luns_per_target = STORVSC_MAX_LUNS_PER_TARGET;
1775 max_targets = STORVSC_MAX_TARGETS;
1776 max_channels = STORVSC_MAX_CHANNELS;
1778 * On Windows8 and above, we support sub-channels for storage.
1779 * The number of sub-channels offerred is based on the number of
1780 * VCPUs in the guest.
1782 max_sub_channels = (num_cpus / storvsc_vcpus_per_sub_channel);
1785 scsi_driver.can_queue = (max_outstanding_req_per_channel *
1786 (max_sub_channels + 1));
1788 host = scsi_host_alloc(&scsi_driver,
1789 sizeof(struct hv_host_device));
1793 host_dev = shost_priv(host);
1794 memset(host_dev, 0, sizeof(struct hv_host_device));
1796 host_dev->port = host->host_no;
1797 host_dev->dev = device;
1800 stor_device = kzalloc(sizeof(struct storvsc_device), GFP_KERNEL);
1806 stor_device->destroy = false;
1807 stor_device->open_sub_channel = false;
1808 init_waitqueue_head(&stor_device->waiting_to_drain);
1809 stor_device->device = device;
1810 stor_device->host = host;
1811 hv_set_drvdata(device, stor_device);
1813 stor_device->port_number = host->host_no;
1814 ret = storvsc_connect_to_vsp(device, storvsc_ringbuffer_size);
1818 host_dev->path = stor_device->path_id;
1819 host_dev->target = stor_device->target_id;
1821 switch (dev_id->driver_data) {
1823 host->max_lun = STORVSC_FC_MAX_LUNS_PER_TARGET;
1824 host->max_id = STORVSC_FC_MAX_TARGETS;
1825 host->max_channel = STORVSC_FC_MAX_CHANNELS - 1;
1829 host->max_lun = max_luns_per_target;
1830 host->max_id = max_targets;
1831 host->max_channel = max_channels - 1;
1835 host->max_lun = STORVSC_IDE_MAX_LUNS_PER_TARGET;
1836 host->max_id = STORVSC_IDE_MAX_TARGETS;
1837 host->max_channel = STORVSC_IDE_MAX_CHANNELS - 1;
1840 /* max cmd length */
1841 host->max_cmd_len = STORVSC_MAX_CMD_LEN;
1844 * set the table size based on the info we got
1847 host->sg_tablesize = (stor_device->max_transfer_bytes >> PAGE_SHIFT);
1849 /* Register the HBA and start the scsi bus scan */
1850 ret = scsi_add_host(host, &device->device);
1855 scsi_scan_host(host);
1857 target = (device->dev_instance.b[5] << 8 |
1858 device->dev_instance.b[4]);
1859 ret = scsi_add_device(host, 0, target, 0);
1861 scsi_remove_host(host);
1869 * Once we have connected with the host, we would need to
1870 * to invoke storvsc_dev_remove() to rollback this state and
1871 * this call also frees up the stor_device; hence the jump around
1874 storvsc_dev_remove(device);
1881 scsi_host_put(host);
1885 static int storvsc_remove(struct hv_device *dev)
1887 struct storvsc_device *stor_device = hv_get_drvdata(dev);
1888 struct Scsi_Host *host = stor_device->host;
1890 scsi_remove_host(host);
1891 storvsc_dev_remove(dev);
1892 scsi_host_put(host);
1897 static struct hv_driver storvsc_drv = {
1898 .name = KBUILD_MODNAME,
1899 .id_table = id_table,
1900 .probe = storvsc_probe,
1901 .remove = storvsc_remove,
1904 static int __init storvsc_drv_init(void)
1908 * Divide the ring buffer data size (which is 1 page less
1909 * than the ring buffer size since that page is reserved for
1910 * the ring buffer indices) by the max request size (which is
1911 * vmbus_channel_packet_multipage_buffer + struct vstor_packet + u64)
1913 max_outstanding_req_per_channel =
1914 ((storvsc_ringbuffer_size - PAGE_SIZE) /
1915 ALIGN(MAX_MULTIPAGE_BUFFER_PACKET +
1916 sizeof(struct vstor_packet) + sizeof(u64) -
1920 return vmbus_driver_register(&storvsc_drv);
1923 static void __exit storvsc_drv_exit(void)
1925 vmbus_driver_unregister(&storvsc_drv);
1928 MODULE_LICENSE("GPL");
1929 MODULE_DESCRIPTION("Microsoft Hyper-V virtual storage driver");
1930 module_init(storvsc_drv_init);
1931 module_exit(storvsc_drv_exit);