dm thin metadata: fix __udivdi3 undefined on 32-bit
[linux/fpc-iii.git] / drivers / scsi / storvsc_drv.c
blob44b7a69d022ad0e6a2ebfd2347cfb55119ab71c0
1 /*
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
11 * more details.
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.
17 * Authors:
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>
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/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.
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 * Win8: 5.1
59 * Win8.1: 6.0
60 * Win10: 6.2
63 #define VMSTOR_PROTO_VERSION(MAJOR_, MINOR_) ((((MAJOR_) & 0xff) << 8) | \
64 (((MINOR_) & 0xff)))
66 #define VMSTOR_PROTO_VERSION_WIN6 VMSTOR_PROTO_VERSION(2, 0)
67 #define VMSTOR_PROTO_VERSION_WIN7 VMSTOR_PROTO_VERSION(4, 2)
68 #define VMSTOR_PROTO_VERSION_WIN8 VMSTOR_PROTO_VERSION(5, 1)
69 #define VMSTOR_PROTO_VERSION_WIN8_1 VMSTOR_PROTO_VERSION(6, 0)
70 #define VMSTOR_PROTO_VERSION_WIN10 VMSTOR_PROTO_VERSION(6, 2)
72 /* Packet structure describing virtual storage requests. */
73 enum vstor_packet_operation {
74 VSTOR_OPERATION_COMPLETE_IO = 1,
75 VSTOR_OPERATION_REMOVE_DEVICE = 2,
76 VSTOR_OPERATION_EXECUTE_SRB = 3,
77 VSTOR_OPERATION_RESET_LUN = 4,
78 VSTOR_OPERATION_RESET_ADAPTER = 5,
79 VSTOR_OPERATION_RESET_BUS = 6,
80 VSTOR_OPERATION_BEGIN_INITIALIZATION = 7,
81 VSTOR_OPERATION_END_INITIALIZATION = 8,
82 VSTOR_OPERATION_QUERY_PROTOCOL_VERSION = 9,
83 VSTOR_OPERATION_QUERY_PROPERTIES = 10,
84 VSTOR_OPERATION_ENUMERATE_BUS = 11,
85 VSTOR_OPERATION_FCHBA_DATA = 12,
86 VSTOR_OPERATION_CREATE_SUB_CHANNELS = 13,
87 VSTOR_OPERATION_MAXIMUM = 13
91 * WWN packet for Fibre Channel HBA
94 struct hv_fc_wwn_packet {
95 bool primary_active;
96 u8 reserved1;
97 u8 reserved2;
98 u8 primary_port_wwn[8];
99 u8 primary_node_wwn[8];
100 u8 secondary_port_wwn[8];
101 u8 secondary_node_wwn[8];
107 * SRB Flag Bits
110 #define SRB_FLAGS_QUEUE_ACTION_ENABLE 0x00000002
111 #define SRB_FLAGS_DISABLE_DISCONNECT 0x00000004
112 #define SRB_FLAGS_DISABLE_SYNCH_TRANSFER 0x00000008
113 #define SRB_FLAGS_BYPASS_FROZEN_QUEUE 0x00000010
114 #define SRB_FLAGS_DISABLE_AUTOSENSE 0x00000020
115 #define SRB_FLAGS_DATA_IN 0x00000040
116 #define SRB_FLAGS_DATA_OUT 0x00000080
117 #define SRB_FLAGS_NO_DATA_TRANSFER 0x00000000
118 #define SRB_FLAGS_UNSPECIFIED_DIRECTION (SRB_FLAGS_DATA_IN | SRB_FLAGS_DATA_OUT)
119 #define SRB_FLAGS_NO_QUEUE_FREEZE 0x00000100
120 #define SRB_FLAGS_ADAPTER_CACHE_ENABLE 0x00000200
121 #define SRB_FLAGS_FREE_SENSE_BUFFER 0x00000400
124 * This flag indicates the request is part of the workflow for processing a D3.
126 #define SRB_FLAGS_D3_PROCESSING 0x00000800
127 #define SRB_FLAGS_IS_ACTIVE 0x00010000
128 #define SRB_FLAGS_ALLOCATED_FROM_ZONE 0x00020000
129 #define SRB_FLAGS_SGLIST_FROM_POOL 0x00040000
130 #define SRB_FLAGS_BYPASS_LOCKED_QUEUE 0x00080000
131 #define SRB_FLAGS_NO_KEEP_AWAKE 0x00100000
132 #define SRB_FLAGS_PORT_DRIVER_ALLOCSENSE 0x00200000
133 #define SRB_FLAGS_PORT_DRIVER_SENSEHASPORT 0x00400000
134 #define SRB_FLAGS_DONT_START_NEXT_PACKET 0x00800000
135 #define SRB_FLAGS_PORT_DRIVER_RESERVED 0x0F000000
136 #define SRB_FLAGS_CLASS_DRIVER_RESERVED 0xF0000000
138 #define SP_UNTAGGED ((unsigned char) ~0)
139 #define SRB_SIMPLE_TAG_REQUEST 0x20
142 * Platform neutral description of a scsi request -
143 * this remains the same across the write regardless of 32/64 bit
144 * note: it's patterned off the SCSI_PASS_THROUGH structure
146 #define STORVSC_MAX_CMD_LEN 0x10
148 #define POST_WIN7_STORVSC_SENSE_BUFFER_SIZE 0x14
149 #define PRE_WIN8_STORVSC_SENSE_BUFFER_SIZE 0x12
151 #define STORVSC_SENSE_BUFFER_SIZE 0x14
152 #define STORVSC_MAX_BUF_LEN_WITH_PADDING 0x14
155 * Sense buffer size changed in win8; have a run-time
156 * variable to track the size we should use. This value will
157 * likely change during protocol negotiation but it is valid
158 * to start by assuming pre-Win8.
160 static int sense_buffer_size = PRE_WIN8_STORVSC_SENSE_BUFFER_SIZE;
163 * The storage protocol version is determined during the
164 * initial exchange with the host. It will indicate which
165 * storage functionality is available in the host.
167 static int vmstor_proto_version;
169 struct vmscsi_win8_extension {
171 * The following were added in Windows 8
173 u16 reserve;
174 u8 queue_tag;
175 u8 queue_action;
176 u32 srb_flags;
177 u32 time_out_value;
178 u32 queue_sort_ey;
179 } __packed;
181 struct vmscsi_request {
182 u16 length;
183 u8 srb_status;
184 u8 scsi_status;
186 u8 port_number;
187 u8 path_id;
188 u8 target_id;
189 u8 lun;
191 u8 cdb_length;
192 u8 sense_info_length;
193 u8 data_in;
194 u8 reserved;
196 u32 data_transfer_length;
198 union {
199 u8 cdb[STORVSC_MAX_CMD_LEN];
200 u8 sense_data[STORVSC_SENSE_BUFFER_SIZE];
201 u8 reserved_array[STORVSC_MAX_BUF_LEN_WITH_PADDING];
204 * The following was added in win8.
206 struct vmscsi_win8_extension win8_extension;
208 } __attribute((packed));
212 * The size of the vmscsi_request has changed in win8. The
213 * additional size is because of new elements added to the
214 * structure. These elements are valid only when we are talking
215 * to a win8 host.
216 * Track the correction to size we need to apply. This value
217 * will likely change during protocol negotiation but it is
218 * valid to start by assuming pre-Win8.
220 static int vmscsi_size_delta = sizeof(struct vmscsi_win8_extension);
223 * The list of storage protocols in order of preference.
225 struct vmstor_protocol {
226 int protocol_version;
227 int sense_buffer_size;
228 int vmscsi_size_delta;
232 static const struct vmstor_protocol vmstor_protocols[] = {
234 VMSTOR_PROTO_VERSION_WIN10,
235 POST_WIN7_STORVSC_SENSE_BUFFER_SIZE,
239 VMSTOR_PROTO_VERSION_WIN8_1,
240 POST_WIN7_STORVSC_SENSE_BUFFER_SIZE,
244 VMSTOR_PROTO_VERSION_WIN8,
245 POST_WIN7_STORVSC_SENSE_BUFFER_SIZE,
249 VMSTOR_PROTO_VERSION_WIN7,
250 PRE_WIN8_STORVSC_SENSE_BUFFER_SIZE,
251 sizeof(struct vmscsi_win8_extension),
254 VMSTOR_PROTO_VERSION_WIN6,
255 PRE_WIN8_STORVSC_SENSE_BUFFER_SIZE,
256 sizeof(struct vmscsi_win8_extension),
262 * This structure is sent during the intialization phase to get the different
263 * properties of the channel.
266 #define STORAGE_CHANNEL_SUPPORTS_MULTI_CHANNEL 0x1
268 struct vmstorage_channel_properties {
269 u32 reserved;
270 u16 max_channel_cnt;
271 u16 reserved1;
273 u32 flags;
274 u32 max_transfer_bytes;
276 u64 reserved2;
277 } __packed;
279 /* This structure is sent during the storage protocol negotiations. */
280 struct vmstorage_protocol_version {
281 /* Major (MSW) and minor (LSW) version numbers. */
282 u16 major_minor;
285 * Revision number is auto-incremented whenever this file is changed
286 * (See FILL_VMSTOR_REVISION macro above). Mismatch does not
287 * definitely indicate incompatibility--but it does indicate mismatched
288 * builds.
289 * This is only used on the windows side. Just set it to 0.
291 u16 revision;
292 } __packed;
294 /* Channel Property Flags */
295 #define STORAGE_CHANNEL_REMOVABLE_FLAG 0x1
296 #define STORAGE_CHANNEL_EMULATED_IDE_FLAG 0x2
298 struct vstor_packet {
299 /* Requested operation type */
300 enum vstor_packet_operation operation;
302 /* Flags - see below for values */
303 u32 flags;
305 /* Status of the request returned from the server side. */
306 u32 status;
308 /* Data payload area */
309 union {
311 * Structure used to forward SCSI commands from the
312 * client to the server.
314 struct vmscsi_request vm_srb;
316 /* Structure used to query channel properties. */
317 struct vmstorage_channel_properties storage_channel_properties;
319 /* Used during version negotiations. */
320 struct vmstorage_protocol_version version;
322 /* Fibre channel address packet */
323 struct hv_fc_wwn_packet wwn_packet;
325 /* Number of sub-channels to create */
326 u16 sub_channel_count;
328 /* This will be the maximum of the union members */
329 u8 buffer[0x34];
331 } __packed;
334 * Packet Flags:
336 * This flag indicates that the server should send back a completion for this
337 * packet.
340 #define REQUEST_COMPLETION_FLAG 0x1
342 /* Matches Windows-end */
343 enum storvsc_request_type {
344 WRITE_TYPE = 0,
345 READ_TYPE,
346 UNKNOWN_TYPE,
350 * SRB status codes and masks; a subset of the codes used here.
353 #define SRB_STATUS_AUTOSENSE_VALID 0x80
354 #define SRB_STATUS_QUEUE_FROZEN 0x40
355 #define SRB_STATUS_INVALID_LUN 0x20
356 #define SRB_STATUS_SUCCESS 0x01
357 #define SRB_STATUS_ABORTED 0x02
358 #define SRB_STATUS_ERROR 0x04
359 #define SRB_STATUS_DATA_OVERRUN 0x12
361 #define SRB_STATUS(status) \
362 (status & ~(SRB_STATUS_AUTOSENSE_VALID | SRB_STATUS_QUEUE_FROZEN))
364 * This is the end of Protocol specific defines.
367 static int storvsc_ringbuffer_size = (256 * PAGE_SIZE);
368 static u32 max_outstanding_req_per_channel;
370 static int storvsc_vcpus_per_sub_channel = 4;
372 module_param(storvsc_ringbuffer_size, int, S_IRUGO);
373 MODULE_PARM_DESC(storvsc_ringbuffer_size, "Ring buffer size (bytes)");
375 module_param(storvsc_vcpus_per_sub_channel, int, S_IRUGO);
376 MODULE_PARM_DESC(vcpus_per_sub_channel, "Ratio of VCPUs to subchannels");
378 * Timeout in seconds for all devices managed by this driver.
380 static int storvsc_timeout = 180;
383 static void storvsc_on_channel_callback(void *context);
385 #define STORVSC_MAX_LUNS_PER_TARGET 255
386 #define STORVSC_MAX_TARGETS 2
387 #define STORVSC_MAX_CHANNELS 8
389 #define STORVSC_FC_MAX_LUNS_PER_TARGET 255
390 #define STORVSC_FC_MAX_TARGETS 128
391 #define STORVSC_FC_MAX_CHANNELS 8
393 #define STORVSC_IDE_MAX_LUNS_PER_TARGET 64
394 #define STORVSC_IDE_MAX_TARGETS 1
395 #define STORVSC_IDE_MAX_CHANNELS 1
397 struct storvsc_cmd_request {
398 struct scsi_cmnd *cmd;
400 struct hv_device *device;
402 /* Synchronize the request/response if needed */
403 struct completion wait_event;
405 struct vmbus_channel_packet_multipage_buffer mpb;
406 struct vmbus_packet_mpb_array *payload;
407 u32 payload_sz;
409 struct vstor_packet vstor_packet;
413 /* A storvsc device is a device object that contains a vmbus channel */
414 struct storvsc_device {
415 struct hv_device *device;
417 bool destroy;
418 bool drain_notify;
419 bool open_sub_channel;
420 atomic_t num_outstanding_req;
421 struct Scsi_Host *host;
423 wait_queue_head_t waiting_to_drain;
426 * Each unique Port/Path/Target represents 1 channel ie scsi
427 * controller. In reality, the pathid, targetid is always 0
428 * and the port is set by us
430 unsigned int port_number;
431 unsigned char path_id;
432 unsigned char target_id;
435 * Max I/O, the device can support.
437 u32 max_transfer_bytes;
438 /* Used for vsc/vsp channel reset process */
439 struct storvsc_cmd_request init_request;
440 struct storvsc_cmd_request reset_request;
443 struct hv_host_device {
444 struct hv_device *dev;
445 unsigned int port;
446 unsigned char path;
447 unsigned char target;
450 struct storvsc_scan_work {
451 struct work_struct work;
452 struct Scsi_Host *host;
453 uint lun;
456 static void storvsc_device_scan(struct work_struct *work)
458 struct storvsc_scan_work *wrk;
459 uint lun;
460 struct scsi_device *sdev;
462 wrk = container_of(work, struct storvsc_scan_work, work);
463 lun = wrk->lun;
465 sdev = scsi_device_lookup(wrk->host, 0, 0, lun);
466 if (!sdev)
467 goto done;
468 scsi_rescan_device(&sdev->sdev_gendev);
469 scsi_device_put(sdev);
471 done:
472 kfree(wrk);
475 static void storvsc_host_scan(struct work_struct *work)
477 struct storvsc_scan_work *wrk;
478 struct Scsi_Host *host;
479 struct scsi_device *sdev;
481 wrk = container_of(work, struct storvsc_scan_work, work);
482 host = wrk->host;
485 * Before scanning the host, first check to see if any of the
486 * currrently known devices have been hot removed. We issue a
487 * "unit ready" command against all currently known devices.
488 * This I/O will result in an error for devices that have been
489 * removed. As part of handling the I/O error, we remove the device.
491 * When a LUN is added or removed, the host sends us a signal to
492 * scan the host. Thus we are forced to discover the LUNs that
493 * may have been removed this way.
495 mutex_lock(&host->scan_mutex);
496 shost_for_each_device(sdev, host)
497 scsi_test_unit_ready(sdev, 1, 1, NULL);
498 mutex_unlock(&host->scan_mutex);
500 * Now scan the host to discover LUNs that may have been added.
502 scsi_scan_host(host);
504 kfree(wrk);
507 static void storvsc_remove_lun(struct work_struct *work)
509 struct storvsc_scan_work *wrk;
510 struct scsi_device *sdev;
512 wrk = container_of(work, struct storvsc_scan_work, work);
513 if (!scsi_host_get(wrk->host))
514 goto done;
516 sdev = scsi_device_lookup(wrk->host, 0, 0, wrk->lun);
518 if (sdev) {
519 scsi_remove_device(sdev);
520 scsi_device_put(sdev);
522 scsi_host_put(wrk->host);
524 done:
525 kfree(wrk);
530 * We can get incoming messages from the host that are not in response to
531 * messages that we have sent out. An example of this would be messages
532 * received by the guest to notify dynamic addition/removal of LUNs. To
533 * deal with potential race conditions where the driver may be in the
534 * midst of being unloaded when we might receive an unsolicited message
535 * from the host, we have implemented a mechanism to gurantee sequential
536 * consistency:
538 * 1) Once the device is marked as being destroyed, we will fail all
539 * outgoing messages.
540 * 2) We permit incoming messages when the device is being destroyed,
541 * only to properly account for messages already sent out.
544 static inline struct storvsc_device *get_out_stor_device(
545 struct hv_device *device)
547 struct storvsc_device *stor_device;
549 stor_device = hv_get_drvdata(device);
551 if (stor_device && stor_device->destroy)
552 stor_device = NULL;
554 return stor_device;
558 static inline void storvsc_wait_to_drain(struct storvsc_device *dev)
560 dev->drain_notify = true;
561 wait_event(dev->waiting_to_drain,
562 atomic_read(&dev->num_outstanding_req) == 0);
563 dev->drain_notify = false;
566 static inline struct storvsc_device *get_in_stor_device(
567 struct hv_device *device)
569 struct storvsc_device *stor_device;
571 stor_device = hv_get_drvdata(device);
573 if (!stor_device)
574 goto get_in_err;
577 * If the device is being destroyed; allow incoming
578 * traffic only to cleanup outstanding requests.
581 if (stor_device->destroy &&
582 (atomic_read(&stor_device->num_outstanding_req) == 0))
583 stor_device = NULL;
585 get_in_err:
586 return stor_device;
590 static void handle_sc_creation(struct vmbus_channel *new_sc)
592 struct hv_device *device = new_sc->primary_channel->device_obj;
593 struct storvsc_device *stor_device;
594 struct vmstorage_channel_properties props;
596 stor_device = get_out_stor_device(device);
597 if (!stor_device)
598 return;
600 if (stor_device->open_sub_channel == false)
601 return;
603 memset(&props, 0, sizeof(struct vmstorage_channel_properties));
605 vmbus_open(new_sc,
606 storvsc_ringbuffer_size,
607 storvsc_ringbuffer_size,
608 (void *)&props,
609 sizeof(struct vmstorage_channel_properties),
610 storvsc_on_channel_callback, new_sc);
613 static void handle_multichannel_storage(struct hv_device *device, int max_chns)
615 struct storvsc_device *stor_device;
616 int num_cpus = num_online_cpus();
617 int num_sc;
618 struct storvsc_cmd_request *request;
619 struct vstor_packet *vstor_packet;
620 int ret, t;
622 num_sc = ((max_chns > num_cpus) ? num_cpus : max_chns);
623 stor_device = get_out_stor_device(device);
624 if (!stor_device)
625 return;
627 request = &stor_device->init_request;
628 vstor_packet = &request->vstor_packet;
630 stor_device->open_sub_channel = true;
632 * Establish a handler for dealing with subchannels.
634 vmbus_set_sc_create_callback(device->channel, handle_sc_creation);
637 * Check to see if sub-channels have already been created. This
638 * can happen when this driver is re-loaded after unloading.
641 if (vmbus_are_subchannels_present(device->channel))
642 return;
644 stor_device->open_sub_channel = false;
646 * Request the host to create sub-channels.
648 memset(request, 0, sizeof(struct storvsc_cmd_request));
649 init_completion(&request->wait_event);
650 vstor_packet->operation = VSTOR_OPERATION_CREATE_SUB_CHANNELS;
651 vstor_packet->flags = REQUEST_COMPLETION_FLAG;
652 vstor_packet->sub_channel_count = num_sc;
654 ret = vmbus_sendpacket(device->channel, vstor_packet,
655 (sizeof(struct vstor_packet) -
656 vmscsi_size_delta),
657 (unsigned long)request,
658 VM_PKT_DATA_INBAND,
659 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
661 if (ret != 0)
662 return;
664 t = wait_for_completion_timeout(&request->wait_event, 10*HZ);
665 if (t == 0)
666 return;
668 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
669 vstor_packet->status != 0)
670 return;
673 * Now that we created the sub-channels, invoke the check; this
674 * may trigger the callback.
676 stor_device->open_sub_channel = true;
677 vmbus_are_subchannels_present(device->channel);
680 static int storvsc_channel_init(struct hv_device *device)
682 struct storvsc_device *stor_device;
683 struct storvsc_cmd_request *request;
684 struct vstor_packet *vstor_packet;
685 int ret, t, i;
686 int max_chns;
687 bool process_sub_channels = false;
689 stor_device = get_out_stor_device(device);
690 if (!stor_device)
691 return -ENODEV;
693 request = &stor_device->init_request;
694 vstor_packet = &request->vstor_packet;
697 * Now, initiate the vsc/vsp initialization protocol on the open
698 * channel
700 memset(request, 0, sizeof(struct storvsc_cmd_request));
701 init_completion(&request->wait_event);
702 vstor_packet->operation = VSTOR_OPERATION_BEGIN_INITIALIZATION;
703 vstor_packet->flags = REQUEST_COMPLETION_FLAG;
705 ret = vmbus_sendpacket(device->channel, vstor_packet,
706 (sizeof(struct vstor_packet) -
707 vmscsi_size_delta),
708 (unsigned long)request,
709 VM_PKT_DATA_INBAND,
710 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
711 if (ret != 0)
712 goto cleanup;
714 t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
715 if (t == 0) {
716 ret = -ETIMEDOUT;
717 goto cleanup;
720 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
721 vstor_packet->status != 0) {
722 ret = -EINVAL;
723 goto cleanup;
727 for (i = 0; i < ARRAY_SIZE(vmstor_protocols); i++) {
728 /* reuse the packet for version range supported */
729 memset(vstor_packet, 0, sizeof(struct vstor_packet));
730 vstor_packet->operation =
731 VSTOR_OPERATION_QUERY_PROTOCOL_VERSION;
732 vstor_packet->flags = REQUEST_COMPLETION_FLAG;
734 vstor_packet->version.major_minor =
735 vmstor_protocols[i].protocol_version;
738 * The revision number is only used in Windows; set it to 0.
740 vstor_packet->version.revision = 0;
742 ret = vmbus_sendpacket(device->channel, vstor_packet,
743 (sizeof(struct vstor_packet) -
744 vmscsi_size_delta),
745 (unsigned long)request,
746 VM_PKT_DATA_INBAND,
747 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
748 if (ret != 0)
749 goto cleanup;
751 t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
752 if (t == 0) {
753 ret = -ETIMEDOUT;
754 goto cleanup;
757 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO) {
758 ret = -EINVAL;
759 goto cleanup;
762 if (vstor_packet->status == 0) {
763 vmstor_proto_version =
764 vmstor_protocols[i].protocol_version;
766 sense_buffer_size =
767 vmstor_protocols[i].sense_buffer_size;
769 vmscsi_size_delta =
770 vmstor_protocols[i].vmscsi_size_delta;
772 break;
776 if (vstor_packet->status != 0) {
777 ret = -EINVAL;
778 goto cleanup;
782 memset(vstor_packet, 0, sizeof(struct vstor_packet));
783 vstor_packet->operation = VSTOR_OPERATION_QUERY_PROPERTIES;
784 vstor_packet->flags = REQUEST_COMPLETION_FLAG;
786 ret = vmbus_sendpacket(device->channel, vstor_packet,
787 (sizeof(struct vstor_packet) -
788 vmscsi_size_delta),
789 (unsigned long)request,
790 VM_PKT_DATA_INBAND,
791 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
793 if (ret != 0)
794 goto cleanup;
796 t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
797 if (t == 0) {
798 ret = -ETIMEDOUT;
799 goto cleanup;
802 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
803 vstor_packet->status != 0) {
804 ret = -EINVAL;
805 goto cleanup;
809 * Check to see if multi-channel support is there.
810 * Hosts that implement protocol version of 5.1 and above
811 * support multi-channel.
813 max_chns = vstor_packet->storage_channel_properties.max_channel_cnt;
814 if (vmstor_proto_version >= VMSTOR_PROTO_VERSION_WIN8) {
815 if (vstor_packet->storage_channel_properties.flags &
816 STORAGE_CHANNEL_SUPPORTS_MULTI_CHANNEL)
817 process_sub_channels = true;
819 stor_device->max_transfer_bytes =
820 vstor_packet->storage_channel_properties.max_transfer_bytes;
822 memset(vstor_packet, 0, sizeof(struct vstor_packet));
823 vstor_packet->operation = VSTOR_OPERATION_END_INITIALIZATION;
824 vstor_packet->flags = REQUEST_COMPLETION_FLAG;
826 ret = vmbus_sendpacket(device->channel, vstor_packet,
827 (sizeof(struct vstor_packet) -
828 vmscsi_size_delta),
829 (unsigned long)request,
830 VM_PKT_DATA_INBAND,
831 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
833 if (ret != 0)
834 goto cleanup;
836 t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
837 if (t == 0) {
838 ret = -ETIMEDOUT;
839 goto cleanup;
842 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
843 vstor_packet->status != 0) {
844 ret = -EINVAL;
845 goto cleanup;
848 if (process_sub_channels)
849 handle_multichannel_storage(device, max_chns);
852 cleanup:
853 return ret;
856 static void storvsc_handle_error(struct vmscsi_request *vm_srb,
857 struct scsi_cmnd *scmnd,
858 struct Scsi_Host *host,
859 u8 asc, u8 ascq)
861 struct storvsc_scan_work *wrk;
862 void (*process_err_fn)(struct work_struct *work);
863 bool do_work = false;
865 switch (SRB_STATUS(vm_srb->srb_status)) {
866 case SRB_STATUS_ERROR:
868 * Let upper layer deal with error when
869 * sense message is present.
872 if (vm_srb->srb_status & SRB_STATUS_AUTOSENSE_VALID)
873 break;
875 * If there is an error; offline the device since all
876 * error recovery strategies would have already been
877 * deployed on the host side. However, if the command
878 * were a pass-through command deal with it appropriately.
880 switch (scmnd->cmnd[0]) {
881 case ATA_16:
882 case ATA_12:
883 set_host_byte(scmnd, DID_PASSTHROUGH);
884 break;
886 * On Some Windows hosts TEST_UNIT_READY command can return
887 * SRB_STATUS_ERROR, let the upper level code deal with it
888 * based on the sense information.
890 case TEST_UNIT_READY:
891 break;
892 default:
893 set_host_byte(scmnd, DID_ERROR);
895 break;
896 case SRB_STATUS_INVALID_LUN:
897 set_host_byte(scmnd, DID_NO_CONNECT);
898 do_work = true;
899 process_err_fn = storvsc_remove_lun;
900 break;
901 case SRB_STATUS_ABORTED:
902 if (vm_srb->srb_status & SRB_STATUS_AUTOSENSE_VALID &&
903 (asc == 0x2a) && (ascq == 0x9)) {
904 do_work = true;
905 process_err_fn = storvsc_device_scan;
907 * Retry the I/O that trigerred this.
909 set_host_byte(scmnd, DID_REQUEUE);
911 break;
914 if (!do_work)
915 return;
918 * We need to schedule work to process this error; schedule it.
920 wrk = kmalloc(sizeof(struct storvsc_scan_work), GFP_ATOMIC);
921 if (!wrk) {
922 set_host_byte(scmnd, DID_TARGET_FAILURE);
923 return;
926 wrk->host = host;
927 wrk->lun = vm_srb->lun;
928 INIT_WORK(&wrk->work, process_err_fn);
929 schedule_work(&wrk->work);
933 static void storvsc_command_completion(struct storvsc_cmd_request *cmd_request)
935 struct scsi_cmnd *scmnd = cmd_request->cmd;
936 struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
937 struct scsi_sense_hdr sense_hdr;
938 struct vmscsi_request *vm_srb;
939 u32 data_transfer_length;
940 struct Scsi_Host *host;
941 struct storvsc_device *stor_dev;
942 struct hv_device *dev = host_dev->dev;
943 u32 payload_sz = cmd_request->payload_sz;
944 void *payload = cmd_request->payload;
946 stor_dev = get_in_stor_device(dev);
947 host = stor_dev->host;
949 vm_srb = &cmd_request->vstor_packet.vm_srb;
950 data_transfer_length = vm_srb->data_transfer_length;
952 scmnd->result = vm_srb->scsi_status;
954 if (scmnd->result) {
955 if (scsi_normalize_sense(scmnd->sense_buffer,
956 SCSI_SENSE_BUFFERSIZE, &sense_hdr))
957 scsi_print_sense_hdr(scmnd->device, "storvsc",
958 &sense_hdr);
961 if (vm_srb->srb_status != SRB_STATUS_SUCCESS) {
962 storvsc_handle_error(vm_srb, scmnd, host, sense_hdr.asc,
963 sense_hdr.ascq);
965 * The Windows driver set data_transfer_length on
966 * SRB_STATUS_DATA_OVERRUN. On other errors, this value
967 * is untouched. In these cases we set it to 0.
969 if (vm_srb->srb_status != SRB_STATUS_DATA_OVERRUN)
970 data_transfer_length = 0;
973 scsi_set_resid(scmnd,
974 cmd_request->payload->range.len - data_transfer_length);
976 scmnd->scsi_done(scmnd);
978 if (payload_sz >
979 sizeof(struct vmbus_channel_packet_multipage_buffer))
980 kfree(payload);
983 static void storvsc_on_io_completion(struct hv_device *device,
984 struct vstor_packet *vstor_packet,
985 struct storvsc_cmd_request *request)
987 struct storvsc_device *stor_device;
988 struct vstor_packet *stor_pkt;
990 stor_device = hv_get_drvdata(device);
991 stor_pkt = &request->vstor_packet;
994 * The current SCSI handling on the host side does
995 * not correctly handle:
996 * INQUIRY command with page code parameter set to 0x80
997 * MODE_SENSE command with cmd[2] == 0x1c
999 * Setup srb and scsi status so this won't be fatal.
1000 * We do this so we can distinguish truly fatal failues
1001 * (srb status == 0x4) and off-line the device in that case.
1004 if ((stor_pkt->vm_srb.cdb[0] == INQUIRY) ||
1005 (stor_pkt->vm_srb.cdb[0] == MODE_SENSE)) {
1006 vstor_packet->vm_srb.scsi_status = 0;
1007 vstor_packet->vm_srb.srb_status = SRB_STATUS_SUCCESS;
1011 /* Copy over the status...etc */
1012 stor_pkt->vm_srb.scsi_status = vstor_packet->vm_srb.scsi_status;
1013 stor_pkt->vm_srb.srb_status = vstor_packet->vm_srb.srb_status;
1014 stor_pkt->vm_srb.sense_info_length =
1015 vstor_packet->vm_srb.sense_info_length;
1018 if ((vstor_packet->vm_srb.scsi_status & 0xFF) == 0x02) {
1019 /* CHECK_CONDITION */
1020 if (vstor_packet->vm_srb.srb_status &
1021 SRB_STATUS_AUTOSENSE_VALID) {
1022 /* autosense data available */
1024 memcpy(request->cmd->sense_buffer,
1025 vstor_packet->vm_srb.sense_data,
1026 vstor_packet->vm_srb.sense_info_length);
1031 stor_pkt->vm_srb.data_transfer_length =
1032 vstor_packet->vm_srb.data_transfer_length;
1034 storvsc_command_completion(request);
1036 if (atomic_dec_and_test(&stor_device->num_outstanding_req) &&
1037 stor_device->drain_notify)
1038 wake_up(&stor_device->waiting_to_drain);
1043 static void storvsc_on_receive(struct hv_device *device,
1044 struct vstor_packet *vstor_packet,
1045 struct storvsc_cmd_request *request)
1047 struct storvsc_scan_work *work;
1048 struct storvsc_device *stor_device;
1050 switch (vstor_packet->operation) {
1051 case VSTOR_OPERATION_COMPLETE_IO:
1052 storvsc_on_io_completion(device, vstor_packet, request);
1053 break;
1055 case VSTOR_OPERATION_REMOVE_DEVICE:
1056 case VSTOR_OPERATION_ENUMERATE_BUS:
1057 stor_device = get_in_stor_device(device);
1058 work = kmalloc(sizeof(struct storvsc_scan_work), GFP_ATOMIC);
1059 if (!work)
1060 return;
1062 INIT_WORK(&work->work, storvsc_host_scan);
1063 work->host = stor_device->host;
1064 schedule_work(&work->work);
1065 break;
1067 default:
1068 break;
1072 static void storvsc_on_channel_callback(void *context)
1074 struct vmbus_channel *channel = (struct vmbus_channel *)context;
1075 struct hv_device *device;
1076 struct storvsc_device *stor_device;
1077 u32 bytes_recvd;
1078 u64 request_id;
1079 unsigned char packet[ALIGN(sizeof(struct vstor_packet), 8)];
1080 struct storvsc_cmd_request *request;
1081 int ret;
1083 if (channel->primary_channel != NULL)
1084 device = channel->primary_channel->device_obj;
1085 else
1086 device = channel->device_obj;
1088 stor_device = get_in_stor_device(device);
1089 if (!stor_device)
1090 return;
1092 do {
1093 ret = vmbus_recvpacket(channel, packet,
1094 ALIGN((sizeof(struct vstor_packet) -
1095 vmscsi_size_delta), 8),
1096 &bytes_recvd, &request_id);
1097 if (ret == 0 && bytes_recvd > 0) {
1099 request = (struct storvsc_cmd_request *)
1100 (unsigned long)request_id;
1102 if ((request == &stor_device->init_request) ||
1103 (request == &stor_device->reset_request)) {
1105 memcpy(&request->vstor_packet, packet,
1106 (sizeof(struct vstor_packet) -
1107 vmscsi_size_delta));
1108 complete(&request->wait_event);
1109 } else {
1110 storvsc_on_receive(device,
1111 (struct vstor_packet *)packet,
1112 request);
1114 } else {
1115 break;
1117 } while (1);
1119 return;
1122 static int storvsc_connect_to_vsp(struct hv_device *device, u32 ring_size)
1124 struct vmstorage_channel_properties props;
1125 int ret;
1127 memset(&props, 0, sizeof(struct vmstorage_channel_properties));
1129 ret = vmbus_open(device->channel,
1130 ring_size,
1131 ring_size,
1132 (void *)&props,
1133 sizeof(struct vmstorage_channel_properties),
1134 storvsc_on_channel_callback, device->channel);
1136 if (ret != 0)
1137 return ret;
1139 ret = storvsc_channel_init(device);
1141 return ret;
1144 static int storvsc_dev_remove(struct hv_device *device)
1146 struct storvsc_device *stor_device;
1147 unsigned long flags;
1149 stor_device = hv_get_drvdata(device);
1151 spin_lock_irqsave(&device->channel->inbound_lock, flags);
1152 stor_device->destroy = true;
1153 spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
1156 * At this point, all outbound traffic should be disable. We
1157 * only allow inbound traffic (responses) to proceed so that
1158 * outstanding requests can be completed.
1161 storvsc_wait_to_drain(stor_device);
1164 * Since we have already drained, we don't need to busy wait
1165 * as was done in final_release_stor_device()
1166 * Note that we cannot set the ext pointer to NULL until
1167 * we have drained - to drain the outgoing packets, we need to
1168 * allow incoming packets.
1170 spin_lock_irqsave(&device->channel->inbound_lock, flags);
1171 hv_set_drvdata(device, NULL);
1172 spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
1174 /* Close the channel */
1175 vmbus_close(device->channel);
1177 kfree(stor_device);
1178 return 0;
1181 static int storvsc_do_io(struct hv_device *device,
1182 struct storvsc_cmd_request *request)
1184 struct storvsc_device *stor_device;
1185 struct vstor_packet *vstor_packet;
1186 struct vmbus_channel *outgoing_channel;
1187 int ret = 0;
1189 vstor_packet = &request->vstor_packet;
1190 stor_device = get_out_stor_device(device);
1192 if (!stor_device)
1193 return -ENODEV;
1196 request->device = device;
1198 * Select an an appropriate channel to send the request out.
1201 outgoing_channel = vmbus_get_outgoing_channel(device->channel);
1204 vstor_packet->flags |= REQUEST_COMPLETION_FLAG;
1206 vstor_packet->vm_srb.length = (sizeof(struct vmscsi_request) -
1207 vmscsi_size_delta);
1210 vstor_packet->vm_srb.sense_info_length = sense_buffer_size;
1213 vstor_packet->vm_srb.data_transfer_length =
1214 request->payload->range.len;
1216 vstor_packet->operation = VSTOR_OPERATION_EXECUTE_SRB;
1218 if (request->payload->range.len) {
1220 ret = vmbus_sendpacket_mpb_desc(outgoing_channel,
1221 request->payload, request->payload_sz,
1222 vstor_packet,
1223 (sizeof(struct vstor_packet) -
1224 vmscsi_size_delta),
1225 (unsigned long)request);
1226 } else {
1227 ret = vmbus_sendpacket(outgoing_channel, vstor_packet,
1228 (sizeof(struct vstor_packet) -
1229 vmscsi_size_delta),
1230 (unsigned long)request,
1231 VM_PKT_DATA_INBAND,
1232 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
1235 if (ret != 0)
1236 return ret;
1238 atomic_inc(&stor_device->num_outstanding_req);
1240 return ret;
1243 static int storvsc_device_alloc(struct scsi_device *sdevice)
1246 * Set blist flag to permit the reading of the VPD pages even when
1247 * the target may claim SPC-2 compliance. MSFT targets currently
1248 * claim SPC-2 compliance while they implement post SPC-2 features.
1249 * With this flag we can correctly handle WRITE_SAME_16 issues.
1251 * Hypervisor reports SCSI_UNKNOWN type for DVD ROM device but
1252 * still supports REPORT LUN.
1254 sdevice->sdev_bflags = BLIST_REPORTLUN2 | BLIST_TRY_VPD_PAGES;
1256 return 0;
1259 static int storvsc_device_configure(struct scsi_device *sdevice)
1262 blk_queue_max_segment_size(sdevice->request_queue, PAGE_SIZE);
1264 blk_queue_bounce_limit(sdevice->request_queue, BLK_BOUNCE_ANY);
1266 blk_queue_rq_timeout(sdevice->request_queue, (storvsc_timeout * HZ));
1268 /* Ensure there are no gaps in presented sgls */
1269 blk_queue_virt_boundary(sdevice->request_queue, PAGE_SIZE - 1);
1271 sdevice->no_write_same = 1;
1274 * If the host is WIN8 or WIN8 R2, claim conformance to SPC-3
1275 * if the device is a MSFT virtual device. If the host is
1276 * WIN10 or newer, allow write_same.
1278 if (!strncmp(sdevice->vendor, "Msft", 4)) {
1279 switch (vmstor_proto_version) {
1280 case VMSTOR_PROTO_VERSION_WIN8:
1281 case VMSTOR_PROTO_VERSION_WIN8_1:
1282 sdevice->scsi_level = SCSI_SPC_3;
1283 break;
1286 if (vmstor_proto_version >= VMSTOR_PROTO_VERSION_WIN10)
1287 sdevice->no_write_same = 0;
1290 return 0;
1293 static int storvsc_get_chs(struct scsi_device *sdev, struct block_device * bdev,
1294 sector_t capacity, int *info)
1296 sector_t nsect = capacity;
1297 sector_t cylinders = nsect;
1298 int heads, sectors_pt;
1301 * We are making up these values; let us keep it simple.
1303 heads = 0xff;
1304 sectors_pt = 0x3f; /* Sectors per track */
1305 sector_div(cylinders, heads * sectors_pt);
1306 if ((sector_t)(cylinders + 1) * heads * sectors_pt < nsect)
1307 cylinders = 0xffff;
1309 info[0] = heads;
1310 info[1] = sectors_pt;
1311 info[2] = (int)cylinders;
1313 return 0;
1316 static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd)
1318 struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
1319 struct hv_device *device = host_dev->dev;
1321 struct storvsc_device *stor_device;
1322 struct storvsc_cmd_request *request;
1323 struct vstor_packet *vstor_packet;
1324 int ret, t;
1327 stor_device = get_out_stor_device(device);
1328 if (!stor_device)
1329 return FAILED;
1331 request = &stor_device->reset_request;
1332 vstor_packet = &request->vstor_packet;
1334 init_completion(&request->wait_event);
1336 vstor_packet->operation = VSTOR_OPERATION_RESET_BUS;
1337 vstor_packet->flags = REQUEST_COMPLETION_FLAG;
1338 vstor_packet->vm_srb.path_id = stor_device->path_id;
1340 ret = vmbus_sendpacket(device->channel, vstor_packet,
1341 (sizeof(struct vstor_packet) -
1342 vmscsi_size_delta),
1343 (unsigned long)&stor_device->reset_request,
1344 VM_PKT_DATA_INBAND,
1345 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
1346 if (ret != 0)
1347 return FAILED;
1349 t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
1350 if (t == 0)
1351 return TIMEOUT_ERROR;
1355 * At this point, all outstanding requests in the adapter
1356 * should have been flushed out and return to us
1357 * There is a potential race here where the host may be in
1358 * the process of responding when we return from here.
1359 * Just wait for all in-transit packets to be accounted for
1360 * before we return from here.
1362 storvsc_wait_to_drain(stor_device);
1364 return SUCCESS;
1368 * The host guarantees to respond to each command, although I/O latencies might
1369 * be unbounded on Azure. Reset the timer unconditionally to give the host a
1370 * chance to perform EH.
1372 static enum blk_eh_timer_return storvsc_eh_timed_out(struct scsi_cmnd *scmnd)
1374 return BLK_EH_RESET_TIMER;
1377 static bool storvsc_scsi_cmd_ok(struct scsi_cmnd *scmnd)
1379 bool allowed = true;
1380 u8 scsi_op = scmnd->cmnd[0];
1382 switch (scsi_op) {
1383 /* the host does not handle WRITE_SAME, log accident usage */
1384 case WRITE_SAME:
1386 * smartd sends this command and the host does not handle
1387 * this. So, don't send it.
1389 case SET_WINDOW:
1390 scmnd->result = ILLEGAL_REQUEST << 16;
1391 allowed = false;
1392 break;
1393 default:
1394 break;
1396 return allowed;
1399 static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
1401 int ret;
1402 struct hv_host_device *host_dev = shost_priv(host);
1403 struct hv_device *dev = host_dev->dev;
1404 struct storvsc_cmd_request *cmd_request = scsi_cmd_priv(scmnd);
1405 int i;
1406 struct scatterlist *sgl;
1407 unsigned int sg_count = 0;
1408 struct vmscsi_request *vm_srb;
1409 struct scatterlist *cur_sgl;
1410 struct vmbus_packet_mpb_array *payload;
1411 u32 payload_sz;
1412 u32 length;
1414 if (vmstor_proto_version <= VMSTOR_PROTO_VERSION_WIN8) {
1416 * On legacy hosts filter unimplemented commands.
1417 * Future hosts are expected to correctly handle
1418 * unsupported commands. Furthermore, it is
1419 * possible that some of the currently
1420 * unsupported commands maybe supported in
1421 * future versions of the host.
1423 if (!storvsc_scsi_cmd_ok(scmnd)) {
1424 scmnd->scsi_done(scmnd);
1425 return 0;
1429 /* Setup the cmd request */
1430 cmd_request->cmd = scmnd;
1432 vm_srb = &cmd_request->vstor_packet.vm_srb;
1433 vm_srb->win8_extension.time_out_value = 60;
1435 vm_srb->win8_extension.srb_flags |=
1436 SRB_FLAGS_DISABLE_SYNCH_TRANSFER;
1438 if (scmnd->device->tagged_supported) {
1439 vm_srb->win8_extension.srb_flags |=
1440 (SRB_FLAGS_QUEUE_ACTION_ENABLE | SRB_FLAGS_NO_QUEUE_FREEZE);
1441 vm_srb->win8_extension.queue_tag = SP_UNTAGGED;
1442 vm_srb->win8_extension.queue_action = SRB_SIMPLE_TAG_REQUEST;
1445 /* Build the SRB */
1446 switch (scmnd->sc_data_direction) {
1447 case DMA_TO_DEVICE:
1448 vm_srb->data_in = WRITE_TYPE;
1449 vm_srb->win8_extension.srb_flags |= SRB_FLAGS_DATA_OUT;
1450 break;
1451 case DMA_FROM_DEVICE:
1452 vm_srb->data_in = READ_TYPE;
1453 vm_srb->win8_extension.srb_flags |= SRB_FLAGS_DATA_IN;
1454 break;
1455 case DMA_NONE:
1456 vm_srb->data_in = UNKNOWN_TYPE;
1457 vm_srb->win8_extension.srb_flags |= SRB_FLAGS_NO_DATA_TRANSFER;
1458 break;
1459 default:
1461 * This is DMA_BIDIRECTIONAL or something else we are never
1462 * supposed to see here.
1464 WARN(1, "Unexpected data direction: %d\n",
1465 scmnd->sc_data_direction);
1466 return -EINVAL;
1470 vm_srb->port_number = host_dev->port;
1471 vm_srb->path_id = scmnd->device->channel;
1472 vm_srb->target_id = scmnd->device->id;
1473 vm_srb->lun = scmnd->device->lun;
1475 vm_srb->cdb_length = scmnd->cmd_len;
1477 memcpy(vm_srb->cdb, scmnd->cmnd, vm_srb->cdb_length);
1479 sgl = (struct scatterlist *)scsi_sglist(scmnd);
1480 sg_count = scsi_sg_count(scmnd);
1482 length = scsi_bufflen(scmnd);
1483 payload = (struct vmbus_packet_mpb_array *)&cmd_request->mpb;
1484 payload_sz = sizeof(cmd_request->mpb);
1486 if (sg_count) {
1487 if (sg_count > MAX_PAGE_BUFFER_COUNT) {
1489 payload_sz = (sg_count * sizeof(void *) +
1490 sizeof(struct vmbus_packet_mpb_array));
1491 payload = kmalloc(payload_sz, GFP_ATOMIC);
1492 if (!payload)
1493 return SCSI_MLQUEUE_DEVICE_BUSY;
1496 payload->range.len = length;
1497 payload->range.offset = sgl[0].offset;
1499 cur_sgl = sgl;
1500 for (i = 0; i < sg_count; i++) {
1501 payload->range.pfn_array[i] =
1502 page_to_pfn(sg_page((cur_sgl)));
1503 cur_sgl = sg_next(cur_sgl);
1506 } else if (scsi_sglist(scmnd)) {
1507 payload->range.len = length;
1508 payload->range.offset =
1509 virt_to_phys(scsi_sglist(scmnd)) & (PAGE_SIZE-1);
1510 payload->range.pfn_array[0] =
1511 virt_to_phys(scsi_sglist(scmnd)) >> PAGE_SHIFT;
1514 cmd_request->payload = payload;
1515 cmd_request->payload_sz = payload_sz;
1517 /* Invokes the vsc to start an IO */
1518 ret = storvsc_do_io(dev, cmd_request);
1520 if (ret == -EAGAIN) {
1521 if (payload_sz > sizeof(cmd_request->mpb))
1522 kfree(payload);
1523 /* no more space */
1524 return SCSI_MLQUEUE_DEVICE_BUSY;
1527 return 0;
1530 static struct scsi_host_template scsi_driver = {
1531 .module = THIS_MODULE,
1532 .name = "storvsc_host_t",
1533 .cmd_size = sizeof(struct storvsc_cmd_request),
1534 .bios_param = storvsc_get_chs,
1535 .queuecommand = storvsc_queuecommand,
1536 .eh_host_reset_handler = storvsc_host_reset_handler,
1537 .proc_name = "storvsc_host",
1538 .eh_timed_out = storvsc_eh_timed_out,
1539 .slave_alloc = storvsc_device_alloc,
1540 .slave_configure = storvsc_device_configure,
1541 .cmd_per_lun = 2048,
1542 .this_id = -1,
1543 .use_clustering = ENABLE_CLUSTERING,
1544 /* Make sure we dont get a sg segment crosses a page boundary */
1545 .dma_boundary = PAGE_SIZE-1,
1546 .no_write_same = 1,
1549 enum {
1550 SCSI_GUID,
1551 IDE_GUID,
1552 SFC_GUID,
1555 static const struct hv_vmbus_device_id id_table[] = {
1556 /* SCSI guid */
1557 { HV_SCSI_GUID,
1558 .driver_data = SCSI_GUID
1560 /* IDE guid */
1561 { HV_IDE_GUID,
1562 .driver_data = IDE_GUID
1564 /* Fibre Channel GUID */
1566 HV_SYNTHFC_GUID,
1567 .driver_data = SFC_GUID
1569 { },
1572 MODULE_DEVICE_TABLE(vmbus, id_table);
1574 static int storvsc_probe(struct hv_device *device,
1575 const struct hv_vmbus_device_id *dev_id)
1577 int ret;
1578 int num_cpus = num_online_cpus();
1579 struct Scsi_Host *host;
1580 struct hv_host_device *host_dev;
1581 bool dev_is_ide = ((dev_id->driver_data == IDE_GUID) ? true : false);
1582 int target = 0;
1583 struct storvsc_device *stor_device;
1584 int max_luns_per_target;
1585 int max_targets;
1586 int max_channels;
1587 int max_sub_channels = 0;
1590 * Based on the windows host we are running on,
1591 * set state to properly communicate with the host.
1594 if (vmbus_proto_version < VERSION_WIN8) {
1595 max_luns_per_target = STORVSC_IDE_MAX_LUNS_PER_TARGET;
1596 max_targets = STORVSC_IDE_MAX_TARGETS;
1597 max_channels = STORVSC_IDE_MAX_CHANNELS;
1598 } else {
1599 max_luns_per_target = STORVSC_MAX_LUNS_PER_TARGET;
1600 max_targets = STORVSC_MAX_TARGETS;
1601 max_channels = STORVSC_MAX_CHANNELS;
1603 * On Windows8 and above, we support sub-channels for storage.
1604 * The number of sub-channels offerred is based on the number of
1605 * VCPUs in the guest.
1607 max_sub_channels = (num_cpus / storvsc_vcpus_per_sub_channel);
1610 scsi_driver.can_queue = (max_outstanding_req_per_channel *
1611 (max_sub_channels + 1));
1613 host = scsi_host_alloc(&scsi_driver,
1614 sizeof(struct hv_host_device));
1615 if (!host)
1616 return -ENOMEM;
1618 host_dev = shost_priv(host);
1619 memset(host_dev, 0, sizeof(struct hv_host_device));
1621 host_dev->port = host->host_no;
1622 host_dev->dev = device;
1625 stor_device = kzalloc(sizeof(struct storvsc_device), GFP_KERNEL);
1626 if (!stor_device) {
1627 ret = -ENOMEM;
1628 goto err_out0;
1631 stor_device->destroy = false;
1632 stor_device->open_sub_channel = false;
1633 init_waitqueue_head(&stor_device->waiting_to_drain);
1634 stor_device->device = device;
1635 stor_device->host = host;
1636 hv_set_drvdata(device, stor_device);
1638 stor_device->port_number = host->host_no;
1639 ret = storvsc_connect_to_vsp(device, storvsc_ringbuffer_size);
1640 if (ret)
1641 goto err_out1;
1643 host_dev->path = stor_device->path_id;
1644 host_dev->target = stor_device->target_id;
1646 switch (dev_id->driver_data) {
1647 case SFC_GUID:
1648 host->max_lun = STORVSC_FC_MAX_LUNS_PER_TARGET;
1649 host->max_id = STORVSC_FC_MAX_TARGETS;
1650 host->max_channel = STORVSC_FC_MAX_CHANNELS - 1;
1651 break;
1653 case SCSI_GUID:
1654 host->max_lun = max_luns_per_target;
1655 host->max_id = max_targets;
1656 host->max_channel = max_channels - 1;
1657 break;
1659 default:
1660 host->max_lun = STORVSC_IDE_MAX_LUNS_PER_TARGET;
1661 host->max_id = STORVSC_IDE_MAX_TARGETS;
1662 host->max_channel = STORVSC_IDE_MAX_CHANNELS - 1;
1663 break;
1665 /* max cmd length */
1666 host->max_cmd_len = STORVSC_MAX_CMD_LEN;
1669 * set the table size based on the info we got
1670 * from the host.
1672 host->sg_tablesize = (stor_device->max_transfer_bytes >> PAGE_SHIFT);
1674 /* Register the HBA and start the scsi bus scan */
1675 ret = scsi_add_host(host, &device->device);
1676 if (ret != 0)
1677 goto err_out2;
1679 if (!dev_is_ide) {
1680 scsi_scan_host(host);
1681 } else {
1682 target = (device->dev_instance.b[5] << 8 |
1683 device->dev_instance.b[4]);
1684 ret = scsi_add_device(host, 0, target, 0);
1685 if (ret) {
1686 scsi_remove_host(host);
1687 goto err_out2;
1690 return 0;
1692 err_out2:
1694 * Once we have connected with the host, we would need to
1695 * to invoke storvsc_dev_remove() to rollback this state and
1696 * this call also frees up the stor_device; hence the jump around
1697 * err_out1 label.
1699 storvsc_dev_remove(device);
1700 goto err_out0;
1702 err_out1:
1703 kfree(stor_device);
1705 err_out0:
1706 scsi_host_put(host);
1707 return ret;
1710 static int storvsc_remove(struct hv_device *dev)
1712 struct storvsc_device *stor_device = hv_get_drvdata(dev);
1713 struct Scsi_Host *host = stor_device->host;
1715 scsi_remove_host(host);
1716 storvsc_dev_remove(dev);
1717 scsi_host_put(host);
1719 return 0;
1722 static struct hv_driver storvsc_drv = {
1723 .name = KBUILD_MODNAME,
1724 .id_table = id_table,
1725 .probe = storvsc_probe,
1726 .remove = storvsc_remove,
1729 static int __init storvsc_drv_init(void)
1733 * Divide the ring buffer data size (which is 1 page less
1734 * than the ring buffer size since that page is reserved for
1735 * the ring buffer indices) by the max request size (which is
1736 * vmbus_channel_packet_multipage_buffer + struct vstor_packet + u64)
1738 max_outstanding_req_per_channel =
1739 ((storvsc_ringbuffer_size - PAGE_SIZE) /
1740 ALIGN(MAX_MULTIPAGE_BUFFER_PACKET +
1741 sizeof(struct vstor_packet) + sizeof(u64) -
1742 vmscsi_size_delta,
1743 sizeof(u64)));
1745 return vmbus_driver_register(&storvsc_drv);
1748 static void __exit storvsc_drv_exit(void)
1750 vmbus_driver_unregister(&storvsc_drv);
1753 MODULE_LICENSE("GPL");
1754 MODULE_DESCRIPTION("Microsoft Hyper-V virtual storage driver");
1755 module_init(storvsc_drv_init);
1756 module_exit(storvsc_drv_exit);