1 /*
2 * Copyright (c) 2009, Microsoft Corporation.
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms and conditions of the GNU General Public License,
6 * version 2, as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
11 * more details.
12 *
13 * You should have received a copy of the GNU General Public License along with
14 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
15 * Place - Suite 330, Boston, MA 02111-1307 USA.
16 *
17 * Authors:
18 * Haiyang Zhang <haiyangz@microsoft.com>
19 * Hank Janssen <hjanssen@microsoft.com>
20 * K. Y. Srinivasan <kys@microsoft.com>
21 */
22
23 #include <linux/kernel.h>
24 #include <linux/wait.h>
25 #include <linux/sched.h>
26 #include <linux/completion.h>
27 #include <linux/string.h>
28 #include <linux/mm.h>
29 #include <linux/delay.h>
30 #include <linux/init.h>
31 #include <linux/slab.h>
32 #include <linux/module.h>
33 #include <linux/device.h>
34 #include <linux/hyperv.h>
35 #include <linux/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>
44 #include <scsi/scsi_transport_fc.h>
45 #include <scsi/scsi_transport.h>
46
47 /*
48 * All wire protocol details (storage protocol between the guest and the host)
49 * are consolidated here.
50 *
51 * Begin protocol definitions.
52 */
53
54 /*
55 * Version history:
56 * V1 Beta: 0.1
57 * V1 RC < 2008/1/31: 1.0
58 * V1 RC > 2008/1/31: 2.0
59 * Win7: 4.2
60 * Win8: 5.1
61 * Win8.1: 6.0
62 * Win10: 6.2
63 */
64
65 #define VMSTOR_PROTO_VERSION(MAJOR_, MINOR_) ((((MAJOR_) & 0xff) << 8) | \
66 (((MINOR_) & 0xff)))
67
68 #define VMSTOR_PROTO_VERSION_WIN6 VMSTOR_PROTO_VERSION(2, 0)
69 #define VMSTOR_PROTO_VERSION_WIN7 VMSTOR_PROTO_VERSION(4, 2)
70 #define VMSTOR_PROTO_VERSION_WIN8 VMSTOR_PROTO_VERSION(5, 1)
71 #define VMSTOR_PROTO_VERSION_WIN8_1 VMSTOR_PROTO_VERSION(6, 0)
72 #define VMSTOR_PROTO_VERSION_WIN10 VMSTOR_PROTO_VERSION(6, 2)
73
74 /* Packet structure describing virtual storage requests. */
75 enum vstor_packet_operation {
76 VSTOR_OPERATION_COMPLETE_IO = 1,
77 VSTOR_OPERATION_REMOVE_DEVICE = 2,
78 VSTOR_OPERATION_EXECUTE_SRB = 3,
79 VSTOR_OPERATION_RESET_LUN = 4,
80 VSTOR_OPERATION_RESET_ADAPTER = 5,
81 VSTOR_OPERATION_RESET_BUS = 6,
82 VSTOR_OPERATION_BEGIN_INITIALIZATION = 7,
83 VSTOR_OPERATION_END_INITIALIZATION = 8,
84 VSTOR_OPERATION_QUERY_PROTOCOL_VERSION = 9,
85 VSTOR_OPERATION_QUERY_PROPERTIES = 10,
86 VSTOR_OPERATION_ENUMERATE_BUS = 11,
87 VSTOR_OPERATION_FCHBA_DATA = 12,
88 VSTOR_OPERATION_CREATE_SUB_CHANNELS = 13,
89 VSTOR_OPERATION_MAXIMUM = 13
90 };
91
92 /*
93 * WWN packet for Fibre Channel HBA
94 */
95
96 struct hv_fc_wwn_packet {
97 u8 primary_active;
98 u8 reserved1[3];
99 u8 primary_port_wwn[8];
100 u8 primary_node_wwn[8];
101 u8 secondary_port_wwn[8];
102 u8 secondary_node_wwn[8];
103 };
104
105
106
107 /*
108 * SRB Flag Bits
109 */
110
111 #define SRB_FLAGS_QUEUE_ACTION_ENABLE 0x00000002
112 #define SRB_FLAGS_DISABLE_DISCONNECT 0x00000004
113 #define SRB_FLAGS_DISABLE_SYNCH_TRANSFER 0x00000008
114 #define SRB_FLAGS_BYPASS_FROZEN_QUEUE 0x00000010
115 #define SRB_FLAGS_DISABLE_AUTOSENSE 0x00000020
116 #define SRB_FLAGS_DATA_IN 0x00000040
117 #define SRB_FLAGS_DATA_OUT 0x00000080
118 #define SRB_FLAGS_NO_DATA_TRANSFER 0x00000000
119 #define SRB_FLAGS_UNSPECIFIED_DIRECTION (SRB_FLAGS_DATA_IN | SRB_FLAGS_DATA_OUT)
120 #define SRB_FLAGS_NO_QUEUE_FREEZE 0x00000100
121 #define SRB_FLAGS_ADAPTER_CACHE_ENABLE 0x00000200
122 #define SRB_FLAGS_FREE_SENSE_BUFFER 0x00000400
123
124 /*
125 * This flag indicates the request is part of the workflow for processing a D3.
126 */
127 #define SRB_FLAGS_D3_PROCESSING 0x00000800
128 #define SRB_FLAGS_IS_ACTIVE 0x00010000
129 #define SRB_FLAGS_ALLOCATED_FROM_ZONE 0x00020000
130 #define SRB_FLAGS_SGLIST_FROM_POOL 0x00040000
131 #define SRB_FLAGS_BYPASS_LOCKED_QUEUE 0x00080000
132 #define SRB_FLAGS_NO_KEEP_AWAKE 0x00100000
133 #define SRB_FLAGS_PORT_DRIVER_ALLOCSENSE 0x00200000
134 #define SRB_FLAGS_PORT_DRIVER_SENSEHASPORT 0x00400000
135 #define SRB_FLAGS_DONT_START_NEXT_PACKET 0x00800000
136 #define SRB_FLAGS_PORT_DRIVER_RESERVED 0x0F000000
137 #define SRB_FLAGS_CLASS_DRIVER_RESERVED 0xF0000000
138
139 #define SP_UNTAGGED ((unsigned char) ~0)
140 #define SRB_SIMPLE_TAG_REQUEST 0x20
141
142 /*
143 * Platform neutral description of a scsi request -
144 * this remains the same across the write regardless of 32/64 bit
145 * note: it's patterned off the SCSI_PASS_THROUGH structure
146 */
147 #define STORVSC_MAX_CMD_LEN 0x10
148
149 #define POST_WIN7_STORVSC_SENSE_BUFFER_SIZE 0x14
150 #define PRE_WIN8_STORVSC_SENSE_BUFFER_SIZE 0x12
151
152 #define STORVSC_SENSE_BUFFER_SIZE 0x14
153 #define STORVSC_MAX_BUF_LEN_WITH_PADDING 0x14
154
155 /*
156 * Sense buffer size changed in win8; have a run-time
157 * variable to track the size we should use. This value will
158 * likely change during protocol negotiation but it is valid
159 * to start by assuming pre-Win8.
160 */
161 static int sense_buffer_size = PRE_WIN8_STORVSC_SENSE_BUFFER_SIZE;
162
163 /*
164 * The storage protocol version is determined during the
165 * initial exchange with the host. It will indicate which
166 * storage functionality is available in the host.
167 */
168 static int vmstor_proto_version;
169
170 #define STORVSC_LOGGING_NONE 0
171 #define STORVSC_LOGGING_ERROR 1
172 #define STORVSC_LOGGING_WARN 2
173
174 static int logging_level = STORVSC_LOGGING_ERROR;
175 module_param(logging_level, int, S_IRUGO|S_IWUSR);
176 MODULE_PARM_DESC(logging_level,
177 "Logging level, 0 - None, 1 - Error (default), 2 - Warning.");
178
do_logging(int level)179 static inline bool do_logging(int level)
180 {
181 return logging_level >= level;
182 }
183
184 #define storvsc_log(dev, level, fmt, ...) \
185 do { \
186 if (do_logging(level)) \
187 dev_warn(&(dev)->device, fmt, ##__VA_ARGS__); \
188 } while (0)
189
190 struct vmscsi_win8_extension {
191 /*
192 * The following were added in Windows 8
193 */
194 u16 reserve;
195 u8 queue_tag;
196 u8 queue_action;
197 u32 srb_flags;
198 u32 time_out_value;
199 u32 queue_sort_ey;
200 } __packed;
201
202 struct vmscsi_request {
203 u16 length;
204 u8 srb_status;
205 u8 scsi_status;
206
207 u8 port_number;
208 u8 path_id;
209 u8 target_id;
210 u8 lun;
211
212 u8 cdb_length;
213 u8 sense_info_length;
214 u8 data_in;
215 u8 reserved;
216
217 u32 data_transfer_length;
218
219 union {
220 u8 cdb[STORVSC_MAX_CMD_LEN];
221 u8 sense_data[STORVSC_SENSE_BUFFER_SIZE];
222 u8 reserved_array[STORVSC_MAX_BUF_LEN_WITH_PADDING];
223 };
224 /*
225 * The following was added in win8.
226 */
227 struct vmscsi_win8_extension win8_extension;
228
229 } __attribute((packed));
230
231
232 /*
233 * The size of the vmscsi_request has changed in win8. The
234 * additional size is because of new elements added to the
235 * structure. These elements are valid only when we are talking
236 * to a win8 host.
237 * Track the correction to size we need to apply. This value
238 * will likely change during protocol negotiation but it is
239 * valid to start by assuming pre-Win8.
240 */
241 static int vmscsi_size_delta = sizeof(struct vmscsi_win8_extension);
242
243 /*
244 * The list of storage protocols in order of preference.
245 */
246 struct vmstor_protocol {
247 int protocol_version;
248 int sense_buffer_size;
249 int vmscsi_size_delta;
250 };
251
252
253 static const struct vmstor_protocol vmstor_protocols[] = {
254 {
255 VMSTOR_PROTO_VERSION_WIN10,
256 POST_WIN7_STORVSC_SENSE_BUFFER_SIZE,
257 0
258 },
259 {
260 VMSTOR_PROTO_VERSION_WIN8_1,
261 POST_WIN7_STORVSC_SENSE_BUFFER_SIZE,
262 0
263 },
264 {
265 VMSTOR_PROTO_VERSION_WIN8,
266 POST_WIN7_STORVSC_SENSE_BUFFER_SIZE,
267 0
268 },
269 {
270 VMSTOR_PROTO_VERSION_WIN7,
271 PRE_WIN8_STORVSC_SENSE_BUFFER_SIZE,
272 sizeof(struct vmscsi_win8_extension),
273 },
274 {
275 VMSTOR_PROTO_VERSION_WIN6,
276 PRE_WIN8_STORVSC_SENSE_BUFFER_SIZE,
277 sizeof(struct vmscsi_win8_extension),
278 }
279 };
280
281
282 /*
283 * This structure is sent during the initialization phase to get the different
284 * properties of the channel.
285 */
286
287 #define STORAGE_CHANNEL_SUPPORTS_MULTI_CHANNEL 0x1
288
289 struct vmstorage_channel_properties {
290 u32 reserved;
291 u16 max_channel_cnt;
292 u16 reserved1;
293
294 u32 flags;
295 u32 max_transfer_bytes;
296
297 u64 reserved2;
298 } __packed;
299
300 /* This structure is sent during the storage protocol negotiations. */
301 struct vmstorage_protocol_version {
302 /* Major (MSW) and minor (LSW) version numbers. */
303 u16 major_minor;
304
305 /*
306 * Revision number is auto-incremented whenever this file is changed
307 * (See FILL_VMSTOR_REVISION macro above). Mismatch does not
308 * definitely indicate incompatibility--but it does indicate mismatched
309 * builds.
310 * This is only used on the windows side. Just set it to 0.
311 */
312 u16 revision;
313 } __packed;
314
315 /* Channel Property Flags */
316 #define STORAGE_CHANNEL_REMOVABLE_FLAG 0x1
317 #define STORAGE_CHANNEL_EMULATED_IDE_FLAG 0x2
318
319 struct vstor_packet {
320 /* Requested operation type */
321 enum vstor_packet_operation operation;
322
323 /* Flags - see below for values */
324 u32 flags;
325
326 /* Status of the request returned from the server side. */
327 u32 status;
328
329 /* Data payload area */
330 union {
331 /*
332 * Structure used to forward SCSI commands from the
333 * client to the server.
334 */
335 struct vmscsi_request vm_srb;
336
337 /* Structure used to query channel properties. */
338 struct vmstorage_channel_properties storage_channel_properties;
339
340 /* Used during version negotiations. */
341 struct vmstorage_protocol_version version;
342
343 /* Fibre channel address packet */
344 struct hv_fc_wwn_packet wwn_packet;
345
346 /* Number of sub-channels to create */
347 u16 sub_channel_count;
348
349 /* This will be the maximum of the union members */
350 u8 buffer[0x34];
351 };
352 } __packed;
353
354 /*
355 * Packet Flags:
356 *
357 * This flag indicates that the server should send back a completion for this
358 * packet.
359 */
360
361 #define REQUEST_COMPLETION_FLAG 0x1
362
363 /* Matches Windows-end */
364 enum storvsc_request_type {
365 WRITE_TYPE = 0,
366 READ_TYPE,
367 UNKNOWN_TYPE,
368 };
369
370 /*
371 * SRB status codes and masks; a subset of the codes used here.
372 */
373
374 #define SRB_STATUS_AUTOSENSE_VALID 0x80
375 #define SRB_STATUS_QUEUE_FROZEN 0x40
376 #define SRB_STATUS_INVALID_LUN 0x20
377 #define SRB_STATUS_SUCCESS 0x01
378 #define SRB_STATUS_ABORTED 0x02
379 #define SRB_STATUS_ERROR 0x04
380 #define SRB_STATUS_DATA_OVERRUN 0x12
381
382 #define SRB_STATUS(status) \
383 (status & ~(SRB_STATUS_AUTOSENSE_VALID | SRB_STATUS_QUEUE_FROZEN))
384 /*
385 * This is the end of Protocol specific defines.
386 */
387
388 static int storvsc_ringbuffer_size = (256 * PAGE_SIZE);
389 static u32 max_outstanding_req_per_channel;
390
391 static int storvsc_vcpus_per_sub_channel = 4;
392
393 module_param(storvsc_ringbuffer_size, int, S_IRUGO);
394 MODULE_PARM_DESC(storvsc_ringbuffer_size, "Ring buffer size (bytes)");
395
396 module_param(storvsc_vcpus_per_sub_channel, int, S_IRUGO);
397 MODULE_PARM_DESC(storvsc_vcpus_per_sub_channel, "Ratio of VCPUs to subchannels");
398
399 static int ring_avail_percent_lowater = 10;
400 module_param(ring_avail_percent_lowater, int, S_IRUGO);
401 MODULE_PARM_DESC(ring_avail_percent_lowater,
402 "Select a channel if available ring size > this in percent");
403
404 /*
405 * Timeout in seconds for all devices managed by this driver.
406 */
407 static int storvsc_timeout = 180;
408
409 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
410 static struct scsi_transport_template *fc_transport_template;
411 #endif
412
413 static void storvsc_on_channel_callback(void *context);
414
415 #define STORVSC_MAX_LUNS_PER_TARGET 255
416 #define STORVSC_MAX_TARGETS 2
417 #define STORVSC_MAX_CHANNELS 8
418
419 #define STORVSC_FC_MAX_LUNS_PER_TARGET 255
420 #define STORVSC_FC_MAX_TARGETS 128
421 #define STORVSC_FC_MAX_CHANNELS 8
422
423 #define STORVSC_IDE_MAX_LUNS_PER_TARGET 64
424 #define STORVSC_IDE_MAX_TARGETS 1
425 #define STORVSC_IDE_MAX_CHANNELS 1
426
427 struct storvsc_cmd_request {
428 struct scsi_cmnd *cmd;
429
430 struct hv_device *device;
431
432 /* Synchronize the request/response if needed */
433 struct completion wait_event;
434
435 struct vmbus_channel_packet_multipage_buffer mpb;
436 struct vmbus_packet_mpb_array *payload;
437 u32 payload_sz;
438
439 struct vstor_packet vstor_packet;
440 };
441
442
443 /* A storvsc device is a device object that contains a vmbus channel */
444 struct storvsc_device {
445 struct hv_device *device;
446
447 bool destroy;
448 bool drain_notify;
449 bool open_sub_channel;
450 atomic_t num_outstanding_req;
451 struct Scsi_Host *host;
452
453 wait_queue_head_t waiting_to_drain;
454
455 /*
456 * Each unique Port/Path/Target represents 1 channel ie scsi
457 * controller. In reality, the pathid, targetid is always 0
458 * and the port is set by us
459 */
460 unsigned int port_number;
461 unsigned char path_id;
462 unsigned char target_id;
463
464 /*
465 * Max I/O, the device can support.
466 */
467 u32 max_transfer_bytes;
468 /*
469 * Number of sub-channels we will open.
470 */
471 u16 num_sc;
472 struct vmbus_channel **stor_chns;
473 /*
474 * Mask of CPUs bound to subchannels.
475 */
476 struct cpumask alloced_cpus;
477 /* Used for vsc/vsp channel reset process */
478 struct storvsc_cmd_request init_request;
479 struct storvsc_cmd_request reset_request;
480 /*
481 * Currently active port and node names for FC devices.
482 */
483 u64 node_name;
484 u64 port_name;
485 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
486 struct fc_rport *rport;
487 #endif
488 };
489
490 struct hv_host_device {
491 struct hv_device *dev;
492 unsigned int port;
493 unsigned char path;
494 unsigned char target;
495 struct workqueue_struct *handle_error_wq;
496 struct work_struct host_scan_work;
497 struct Scsi_Host *host;
498 };
499
500 struct storvsc_scan_work {
501 struct work_struct work;
502 struct Scsi_Host *host;
503 u8 lun;
504 u8 tgt_id;
505 };
506
storvsc_device_scan(struct work_struct * work)507 static void storvsc_device_scan(struct work_struct *work)
508 {
509 struct storvsc_scan_work *wrk;
510 struct scsi_device *sdev;
511
512 wrk = container_of(work, struct storvsc_scan_work, work);
513
514 sdev = scsi_device_lookup(wrk->host, 0, wrk->tgt_id, wrk->lun);
515 if (!sdev)
516 goto done;
517 scsi_rescan_device(&sdev->sdev_gendev);
518 scsi_device_put(sdev);
519
520 done:
521 kfree(wrk);
522 }
523
storvsc_host_scan(struct work_struct * work)524 static void storvsc_host_scan(struct work_struct *work)
525 {
526 struct Scsi_Host *host;
527 struct scsi_device *sdev;
528 struct hv_host_device *host_device =
529 container_of(work, struct hv_host_device, host_scan_work);
530
531 host = host_device->host;
532 /*
533 * Before scanning the host, first check to see if any of the
534 * currrently known devices have been hot removed. We issue a
535 * "unit ready" command against all currently known devices.
536 * This I/O will result in an error for devices that have been
537 * removed. As part of handling the I/O error, we remove the device.
538 *
539 * When a LUN is added or removed, the host sends us a signal to
540 * scan the host. Thus we are forced to discover the LUNs that
541 * may have been removed this way.
542 */
543 mutex_lock(&host->scan_mutex);
544 shost_for_each_device(sdev, host)
545 scsi_test_unit_ready(sdev, 1, 1, NULL);
546 mutex_unlock(&host->scan_mutex);
547 /*
548 * Now scan the host to discover LUNs that may have been added.
549 */
550 scsi_scan_host(host);
551 }
552
storvsc_remove_lun(struct work_struct * work)553 static void storvsc_remove_lun(struct work_struct *work)
554 {
555 struct storvsc_scan_work *wrk;
556 struct scsi_device *sdev;
557
558 wrk = container_of(work, struct storvsc_scan_work, work);
559 if (!scsi_host_get(wrk->host))
560 goto done;
561
562 sdev = scsi_device_lookup(wrk->host, 0, wrk->tgt_id, wrk->lun);
563
564 if (sdev) {
565 scsi_remove_device(sdev);
566 scsi_device_put(sdev);
567 }
568 scsi_host_put(wrk->host);
569
570 done:
571 kfree(wrk);
572 }
573
574
575 /*
576 * We can get incoming messages from the host that are not in response to
577 * messages that we have sent out. An example of this would be messages
578 * received by the guest to notify dynamic addition/removal of LUNs. To
579 * deal with potential race conditions where the driver may be in the
580 * midst of being unloaded when we might receive an unsolicited message
581 * from the host, we have implemented a mechanism to gurantee sequential
582 * consistency:
583 *
584 * 1) Once the device is marked as being destroyed, we will fail all
585 * outgoing messages.
586 * 2) We permit incoming messages when the device is being destroyed,
587 * only to properly account for messages already sent out.
588 */
589
get_out_stor_device(struct hv_device * device)590 static inline struct storvsc_device *get_out_stor_device(
591 struct hv_device *device)
592 {
593 struct storvsc_device *stor_device;
594
595 stor_device = hv_get_drvdata(device);
596
597 if (stor_device && stor_device->destroy)
598 stor_device = NULL;
599
600 return stor_device;
601 }
602
603
storvsc_wait_to_drain(struct storvsc_device * dev)604 static inline void storvsc_wait_to_drain(struct storvsc_device *dev)
605 {
606 dev->drain_notify = true;
607 wait_event(dev->waiting_to_drain,
608 atomic_read(&dev->num_outstanding_req) == 0);
609 dev->drain_notify = false;
610 }
611
get_in_stor_device(struct hv_device * device)612 static inline struct storvsc_device *get_in_stor_device(
613 struct hv_device *device)
614 {
615 struct storvsc_device *stor_device;
616
617 stor_device = hv_get_drvdata(device);
618
619 if (!stor_device)
620 goto get_in_err;
621
622 /*
623 * If the device is being destroyed; allow incoming
624 * traffic only to cleanup outstanding requests.
625 */
626
627 if (stor_device->destroy &&
628 (atomic_read(&stor_device->num_outstanding_req) == 0))
629 stor_device = NULL;
630
631 get_in_err:
632 return stor_device;
633
634 }
635
handle_sc_creation(struct vmbus_channel * new_sc)636 static void handle_sc_creation(struct vmbus_channel *new_sc)
637 {
638 struct hv_device *device = new_sc->primary_channel->device_obj;
639 struct storvsc_device *stor_device;
640 struct vmstorage_channel_properties props;
641
642 stor_device = get_out_stor_device(device);
643 if (!stor_device)
644 return;
645
646 if (stor_device->open_sub_channel == false)
647 return;
648
649 memset(&props, 0, sizeof(struct vmstorage_channel_properties));
650
651 vmbus_open(new_sc,
652 storvsc_ringbuffer_size,
653 storvsc_ringbuffer_size,
654 (void *)&props,
655 sizeof(struct vmstorage_channel_properties),
656 storvsc_on_channel_callback, new_sc);
657
658 if (new_sc->state == CHANNEL_OPENED_STATE) {
659 stor_device->stor_chns[new_sc->target_cpu] = new_sc;
660 cpumask_set_cpu(new_sc->target_cpu, &stor_device->alloced_cpus);
661 }
662 }
663
handle_multichannel_storage(struct hv_device * device,int max_chns)664 static void handle_multichannel_storage(struct hv_device *device, int max_chns)
665 {
666 struct storvsc_device *stor_device;
667 int num_cpus = num_online_cpus();
668 int num_sc;
669 struct storvsc_cmd_request *request;
670 struct vstor_packet *vstor_packet;
671 int ret, t;
672
673 num_sc = ((max_chns > num_cpus) ? num_cpus : max_chns);
674 stor_device = get_out_stor_device(device);
675 if (!stor_device)
676 return;
677
678 stor_device->num_sc = num_sc;
679 request = &stor_device->init_request;
680 vstor_packet = &request->vstor_packet;
681
682 stor_device->open_sub_channel = true;
683 /*
684 * Establish a handler for dealing with subchannels.
685 */
686 vmbus_set_sc_create_callback(device->channel, handle_sc_creation);
687
688 /*
689 * Check to see if sub-channels have already been created. This
690 * can happen when this driver is re-loaded after unloading.
691 */
692
693 if (vmbus_are_subchannels_present(device->channel))
694 return;
695
696 stor_device->open_sub_channel = false;
697 /*
698 * Request the host to create sub-channels.
699 */
700 memset(request, 0, sizeof(struct storvsc_cmd_request));
701 init_completion(&request->wait_event);
702 vstor_packet->operation = VSTOR_OPERATION_CREATE_SUB_CHANNELS;
703 vstor_packet->flags = REQUEST_COMPLETION_FLAG;
704 vstor_packet->sub_channel_count = num_sc;
705
706 ret = vmbus_sendpacket(device->channel, vstor_packet,
707 (sizeof(struct vstor_packet) -
708 vmscsi_size_delta),
709 (unsigned long)request,
710 VM_PKT_DATA_INBAND,
711 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
712
713 if (ret != 0)
714 return;
715
716 t = wait_for_completion_timeout(&request->wait_event, 10*HZ);
717 if (t == 0)
718 return;
719
720 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
721 vstor_packet->status != 0)
722 return;
723
724 /*
725 * Now that we created the sub-channels, invoke the check; this
726 * may trigger the callback.
727 */
728 stor_device->open_sub_channel = true;
729 vmbus_are_subchannels_present(device->channel);
730 }
731
cache_wwn(struct storvsc_device * stor_device,struct vstor_packet * vstor_packet)732 static void cache_wwn(struct storvsc_device *stor_device,
733 struct vstor_packet *vstor_packet)
734 {
735 /*
736 * Cache the currently active port and node ww names.
737 */
738 if (vstor_packet->wwn_packet.primary_active) {
739 stor_device->node_name =
740 wwn_to_u64(vstor_packet->wwn_packet.primary_node_wwn);
741 stor_device->port_name =
742 wwn_to_u64(vstor_packet->wwn_packet.primary_port_wwn);
743 } else {
744 stor_device->node_name =
745 wwn_to_u64(vstor_packet->wwn_packet.secondary_node_wwn);
746 stor_device->port_name =
747 wwn_to_u64(vstor_packet->wwn_packet.secondary_port_wwn);
748 }
749 }
750
751
storvsc_execute_vstor_op(struct hv_device * device,struct storvsc_cmd_request * request,bool status_check)752 static int storvsc_execute_vstor_op(struct hv_device *device,
753 struct storvsc_cmd_request *request,
754 bool status_check)
755 {
756 struct vstor_packet *vstor_packet;
757 int ret, t;
758
759 vstor_packet = &request->vstor_packet;
760
761 init_completion(&request->wait_event);
762 vstor_packet->flags = REQUEST_COMPLETION_FLAG;
763
764 ret = vmbus_sendpacket(device->channel, vstor_packet,
765 (sizeof(struct vstor_packet) -
766 vmscsi_size_delta),
767 (unsigned long)request,
768 VM_PKT_DATA_INBAND,
769 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
770 if (ret != 0)
771 return ret;
772
773 t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
774 if (t == 0)
775 return -ETIMEDOUT;
776
777 if (!status_check)
778 return ret;
779
780 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO ||
781 vstor_packet->status != 0)
782 return -EINVAL;
783
784 return ret;
785 }
786
storvsc_channel_init(struct hv_device * device,bool is_fc)787 static int storvsc_channel_init(struct hv_device *device, bool is_fc)
788 {
789 struct storvsc_device *stor_device;
790 struct storvsc_cmd_request *request;
791 struct vstor_packet *vstor_packet;
792 int ret, i;
793 int max_chns;
794 bool process_sub_channels = false;
795
796 stor_device = get_out_stor_device(device);
797 if (!stor_device)
798 return -ENODEV;
799
800 request = &stor_device->init_request;
801 vstor_packet = &request->vstor_packet;
802
803 /*
804 * Now, initiate the vsc/vsp initialization protocol on the open
805 * channel
806 */
807 memset(request, 0, sizeof(struct storvsc_cmd_request));
808 vstor_packet->operation = VSTOR_OPERATION_BEGIN_INITIALIZATION;
809 ret = storvsc_execute_vstor_op(device, request, true);
810 if (ret)
811 return ret;
812 /*
813 * Query host supported protocol version.
814 */
815
816 for (i = 0; i < ARRAY_SIZE(vmstor_protocols); i++) {
817 /* reuse the packet for version range supported */
818 memset(vstor_packet, 0, sizeof(struct vstor_packet));
819 vstor_packet->operation =
820 VSTOR_OPERATION_QUERY_PROTOCOL_VERSION;
821
822 vstor_packet->version.major_minor =
823 vmstor_protocols[i].protocol_version;
824
825 /*
826 * The revision number is only used in Windows; set it to 0.
827 */
828 vstor_packet->version.revision = 0;
829 ret = storvsc_execute_vstor_op(device, request, false);
830 if (ret != 0)
831 return ret;
832
833 if (vstor_packet->operation != VSTOR_OPERATION_COMPLETE_IO)
834 return -EINVAL;
835
836 if (vstor_packet->status == 0) {
837 vmstor_proto_version =
838 vmstor_protocols[i].protocol_version;
839
840 sense_buffer_size =
841 vmstor_protocols[i].sense_buffer_size;
842
843 vmscsi_size_delta =
844 vmstor_protocols[i].vmscsi_size_delta;
845
846 break;
847 }
848 }
849
850 if (vstor_packet->status != 0)
851 return -EINVAL;
852
853
854 memset(vstor_packet, 0, sizeof(struct vstor_packet));
855 vstor_packet->operation = VSTOR_OPERATION_QUERY_PROPERTIES;
856 ret = storvsc_execute_vstor_op(device, request, true);
857 if (ret != 0)
858 return ret;
859
860 /*
861 * Check to see if multi-channel support is there.
862 * Hosts that implement protocol version of 5.1 and above
863 * support multi-channel.
864 */
865 max_chns = vstor_packet->storage_channel_properties.max_channel_cnt;
866
867 /*
868 * Allocate state to manage the sub-channels.
869 * We allocate an array based on the numbers of possible CPUs
870 * (Hyper-V does not support cpu online/offline).
871 * This Array will be sparseley populated with unique
872 * channels - primary + sub-channels.
873 * We will however populate all the slots to evenly distribute
874 * the load.
875 */
876 stor_device->stor_chns = kcalloc(num_possible_cpus(), sizeof(void *),
877 GFP_KERNEL);
878 if (stor_device->stor_chns == NULL)
879 return -ENOMEM;
880
881 stor_device->stor_chns[device->channel->target_cpu] = device->channel;
882 cpumask_set_cpu(device->channel->target_cpu,
883 &stor_device->alloced_cpus);
884
885 if (vmstor_proto_version >= VMSTOR_PROTO_VERSION_WIN8) {
886 if (vstor_packet->storage_channel_properties.flags &
887 STORAGE_CHANNEL_SUPPORTS_MULTI_CHANNEL)
888 process_sub_channels = true;
889 }
890 stor_device->max_transfer_bytes =
891 vstor_packet->storage_channel_properties.max_transfer_bytes;
892
893 if (!is_fc)
894 goto done;
895
896 /*
897 * For FC devices retrieve FC HBA data.
898 */
899 memset(vstor_packet, 0, sizeof(struct vstor_packet));
900 vstor_packet->operation = VSTOR_OPERATION_FCHBA_DATA;
901 ret = storvsc_execute_vstor_op(device, request, true);
902 if (ret != 0)
903 return ret;
904
905 /*
906 * Cache the currently active port and node ww names.
907 */
908 cache_wwn(stor_device, vstor_packet);
909
910 done:
911
912 memset(vstor_packet, 0, sizeof(struct vstor_packet));
913 vstor_packet->operation = VSTOR_OPERATION_END_INITIALIZATION;
914 ret = storvsc_execute_vstor_op(device, request, true);
915 if (ret != 0)
916 return ret;
917
918 if (process_sub_channels)
919 handle_multichannel_storage(device, max_chns);
920
921 return ret;
922 }
923
storvsc_handle_error(struct vmscsi_request * vm_srb,struct scsi_cmnd * scmnd,struct Scsi_Host * host,u8 asc,u8 ascq)924 static void storvsc_handle_error(struct vmscsi_request *vm_srb,
925 struct scsi_cmnd *scmnd,
926 struct Scsi_Host *host,
927 u8 asc, u8 ascq)
928 {
929 struct storvsc_scan_work *wrk;
930 void (*process_err_fn)(struct work_struct *work);
931 struct hv_host_device *host_dev = shost_priv(host);
932 bool do_work = false;
933
934 switch (SRB_STATUS(vm_srb->srb_status)) {
935 case SRB_STATUS_ERROR:
936 /*
937 * Let upper layer deal with error when
938 * sense message is present.
939 */
940
941 if (vm_srb->srb_status & SRB_STATUS_AUTOSENSE_VALID)
942 break;
943 /*
944 * If there is an error; offline the device since all
945 * error recovery strategies would have already been
946 * deployed on the host side. However, if the command
947 * were a pass-through command deal with it appropriately.
948 */
949 switch (scmnd->cmnd[0]) {
950 case ATA_16:
951 case ATA_12:
952 set_host_byte(scmnd, DID_PASSTHROUGH);
953 break;
954 /*
955 * On Some Windows hosts TEST_UNIT_READY command can return
956 * SRB_STATUS_ERROR, let the upper level code deal with it
957 * based on the sense information.
958 */
959 case TEST_UNIT_READY:
960 break;
961 default:
962 set_host_byte(scmnd, DID_ERROR);
963 }
964 break;
965 case SRB_STATUS_INVALID_LUN:
966 set_host_byte(scmnd, DID_NO_CONNECT);
967 do_work = true;
968 process_err_fn = storvsc_remove_lun;
969 break;
970 case SRB_STATUS_ABORTED:
971 if (vm_srb->srb_status & SRB_STATUS_AUTOSENSE_VALID &&
972 (asc == 0x2a) && (ascq == 0x9)) {
973 do_work = true;
974 process_err_fn = storvsc_device_scan;
975 /*
976 * Retry the I/O that trigerred this.
977 */
978 set_host_byte(scmnd, DID_REQUEUE);
979 }
980 break;
981 }
982
983 if (!do_work)
984 return;
985
986 /*
987 * We need to schedule work to process this error; schedule it.
988 */
989 wrk = kmalloc(sizeof(struct storvsc_scan_work), GFP_ATOMIC);
990 if (!wrk) {
991 set_host_byte(scmnd, DID_TARGET_FAILURE);
992 return;
993 }
994
995 wrk->host = host;
996 wrk->lun = vm_srb->lun;
997 wrk->tgt_id = vm_srb->target_id;
998 INIT_WORK(&wrk->work, process_err_fn);
999 queue_work(host_dev->handle_error_wq, &wrk->work);
1000 }
1001
1002
storvsc_command_completion(struct storvsc_cmd_request * cmd_request,struct storvsc_device * stor_dev)1003 static void storvsc_command_completion(struct storvsc_cmd_request *cmd_request,
1004 struct storvsc_device *stor_dev)
1005 {
1006 struct scsi_cmnd *scmnd = cmd_request->cmd;
1007 struct scsi_sense_hdr sense_hdr;
1008 struct vmscsi_request *vm_srb;
1009 u32 data_transfer_length;
1010 struct Scsi_Host *host;
1011 u32 payload_sz = cmd_request->payload_sz;
1012 void *payload = cmd_request->payload;
1013
1014 host = stor_dev->host;
1015
1016 vm_srb = &cmd_request->vstor_packet.vm_srb;
1017 data_transfer_length = vm_srb->data_transfer_length;
1018
1019 scmnd->result = vm_srb->scsi_status;
1020
1021 if (scmnd->result) {
1022 if (scsi_normalize_sense(scmnd->sense_buffer,
1023 SCSI_SENSE_BUFFERSIZE, &sense_hdr) &&
1024 !(sense_hdr.sense_key == NOT_READY &&
1025 sense_hdr.asc == 0x03A) &&
1026 do_logging(STORVSC_LOGGING_ERROR))
1027 scsi_print_sense_hdr(scmnd->device, "storvsc",
1028 &sense_hdr);
1029 }
1030
1031 if (vm_srb->srb_status != SRB_STATUS_SUCCESS) {
1032 storvsc_handle_error(vm_srb, scmnd, host, sense_hdr.asc,
1033 sense_hdr.ascq);
1034 /*
1035 * The Windows driver set data_transfer_length on
1036 * SRB_STATUS_DATA_OVERRUN. On other errors, this value
1037 * is untouched. In these cases we set it to 0.
1038 */
1039 if (vm_srb->srb_status != SRB_STATUS_DATA_OVERRUN)
1040 data_transfer_length = 0;
1041 }
1042
1043 scsi_set_resid(scmnd,
1044 cmd_request->payload->range.len - data_transfer_length);
1045
1046 scmnd->scsi_done(scmnd);
1047
1048 if (payload_sz >
1049 sizeof(struct vmbus_channel_packet_multipage_buffer))
1050 kfree(payload);
1051 }
1052
storvsc_on_io_completion(struct storvsc_device * stor_device,struct vstor_packet * vstor_packet,struct storvsc_cmd_request * request)1053 static void storvsc_on_io_completion(struct storvsc_device *stor_device,
1054 struct vstor_packet *vstor_packet,
1055 struct storvsc_cmd_request *request)
1056 {
1057 struct vstor_packet *stor_pkt;
1058 struct hv_device *device = stor_device->device;
1059
1060 stor_pkt = &request->vstor_packet;
1061
1062 /*
1063 * The current SCSI handling on the host side does
1064 * not correctly handle:
1065 * INQUIRY command with page code parameter set to 0x80
1066 * MODE_SENSE command with cmd[2] == 0x1c
1067 *
1068 * Setup srb and scsi status so this won't be fatal.
1069 * We do this so we can distinguish truly fatal failues
1070 * (srb status == 0x4) and off-line the device in that case.
1071 */
1072
1073 if ((stor_pkt->vm_srb.cdb[0] == INQUIRY) ||
1074 (stor_pkt->vm_srb.cdb[0] == MODE_SENSE)) {
1075 vstor_packet->vm_srb.scsi_status = 0;
1076 vstor_packet->vm_srb.srb_status = SRB_STATUS_SUCCESS;
1077 }
1078
1079
1080 /* Copy over the status...etc */
1081 stor_pkt->vm_srb.scsi_status = vstor_packet->vm_srb.scsi_status;
1082 stor_pkt->vm_srb.srb_status = vstor_packet->vm_srb.srb_status;
1083 stor_pkt->vm_srb.sense_info_length =
1084 vstor_packet->vm_srb.sense_info_length;
1085
1086 if (vstor_packet->vm_srb.scsi_status != 0 ||
1087 vstor_packet->vm_srb.srb_status != SRB_STATUS_SUCCESS)
1088 storvsc_log(device, STORVSC_LOGGING_WARN,
1089 "cmd 0x%x scsi status 0x%x srb status 0x%x\n",
1090 stor_pkt->vm_srb.cdb[0],
1091 vstor_packet->vm_srb.scsi_status,
1092 vstor_packet->vm_srb.srb_status);
1093
1094 if ((vstor_packet->vm_srb.scsi_status & 0xFF) == 0x02) {
1095 /* CHECK_CONDITION */
1096 if (vstor_packet->vm_srb.srb_status &
1097 SRB_STATUS_AUTOSENSE_VALID) {
1098 /* autosense data available */
1099
1100 storvsc_log(device, STORVSC_LOGGING_WARN,
1101 "stor pkt %p autosense data valid - len %d\n",
1102 request, vstor_packet->vm_srb.sense_info_length);
1103
1104 memcpy(request->cmd->sense_buffer,
1105 vstor_packet->vm_srb.sense_data,
1106 vstor_packet->vm_srb.sense_info_length);
1107
1108 }
1109 }
1110
1111 stor_pkt->vm_srb.data_transfer_length =
1112 vstor_packet->vm_srb.data_transfer_length;
1113
1114 storvsc_command_completion(request, stor_device);
1115
1116 if (atomic_dec_and_test(&stor_device->num_outstanding_req) &&
1117 stor_device->drain_notify)
1118 wake_up(&stor_device->waiting_to_drain);
1119
1120
1121 }
1122
storvsc_on_receive(struct storvsc_device * stor_device,struct vstor_packet * vstor_packet,struct storvsc_cmd_request * request)1123 static void storvsc_on_receive(struct storvsc_device *stor_device,
1124 struct vstor_packet *vstor_packet,
1125 struct storvsc_cmd_request *request)
1126 {
1127 struct hv_host_device *host_dev;
1128 switch (vstor_packet->operation) {
1129 case VSTOR_OPERATION_COMPLETE_IO:
1130 storvsc_on_io_completion(stor_device, vstor_packet, request);
1131 break;
1132
1133 case VSTOR_OPERATION_REMOVE_DEVICE:
1134 case VSTOR_OPERATION_ENUMERATE_BUS:
1135 host_dev = shost_priv(stor_device->host);
1136 queue_work(
1137 host_dev->handle_error_wq, &host_dev->host_scan_work);
1138 break;
1139
1140 case VSTOR_OPERATION_FCHBA_DATA:
1141 cache_wwn(stor_device, vstor_packet);
1142 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1143 fc_host_node_name(stor_device->host) = stor_device->node_name;
1144 fc_host_port_name(stor_device->host) = stor_device->port_name;
1145 #endif
1146 break;
1147 default:
1148 break;
1149 }
1150 }
1151
storvsc_on_channel_callback(void * context)1152 static void storvsc_on_channel_callback(void *context)
1153 {
1154 struct vmbus_channel *channel = (struct vmbus_channel *)context;
1155 const struct vmpacket_descriptor *desc;
1156 struct hv_device *device;
1157 struct storvsc_device *stor_device;
1158
1159 if (channel->primary_channel != NULL)
1160 device = channel->primary_channel->device_obj;
1161 else
1162 device = channel->device_obj;
1163
1164 stor_device = get_in_stor_device(device);
1165 if (!stor_device)
1166 return;
1167
1168 foreach_vmbus_pkt(desc, channel) {
1169 void *packet = hv_pkt_data(desc);
1170 struct storvsc_cmd_request *request;
1171
1172 request = (struct storvsc_cmd_request *)
1173 ((unsigned long)desc->trans_id);
1174
1175 if (request == &stor_device->init_request ||
1176 request == &stor_device->reset_request) {
1177 memcpy(&request->vstor_packet, packet,
1178 (sizeof(struct vstor_packet) - vmscsi_size_delta));
1179 complete(&request->wait_event);
1180 } else {
1181 storvsc_on_receive(stor_device, packet, request);
1182 }
1183 }
1184 }
1185
storvsc_connect_to_vsp(struct hv_device * device,u32 ring_size,bool is_fc)1186 static int storvsc_connect_to_vsp(struct hv_device *device, u32 ring_size,
1187 bool is_fc)
1188 {
1189 struct vmstorage_channel_properties props;
1190 int ret;
1191
1192 memset(&props, 0, sizeof(struct vmstorage_channel_properties));
1193
1194 ret = vmbus_open(device->channel,
1195 ring_size,
1196 ring_size,
1197 (void *)&props,
1198 sizeof(struct vmstorage_channel_properties),
1199 storvsc_on_channel_callback, device->channel);
1200
1201 if (ret != 0)
1202 return ret;
1203
1204 ret = storvsc_channel_init(device, is_fc);
1205
1206 return ret;
1207 }
1208
storvsc_dev_remove(struct hv_device * device)1209 static int storvsc_dev_remove(struct hv_device *device)
1210 {
1211 struct storvsc_device *stor_device;
1212
1213 stor_device = hv_get_drvdata(device);
1214
1215 stor_device->destroy = true;
1216
1217 /* Make sure flag is set before waiting */
1218 wmb();
1219
1220 /*
1221 * At this point, all outbound traffic should be disable. We
1222 * only allow inbound traffic (responses) to proceed so that
1223 * outstanding requests can be completed.
1224 */
1225
1226 storvsc_wait_to_drain(stor_device);
1227
1228 /*
1229 * Since we have already drained, we don't need to busy wait
1230 * as was done in final_release_stor_device()
1231 * Note that we cannot set the ext pointer to NULL until
1232 * we have drained - to drain the outgoing packets, we need to
1233 * allow incoming packets.
1234 */
1235 hv_set_drvdata(device, NULL);
1236
1237 /* Close the channel */
1238 vmbus_close(device->channel);
1239
1240 kfree(stor_device->stor_chns);
1241 kfree(stor_device);
1242 return 0;
1243 }
1244
get_og_chn(struct storvsc_device * stor_device,u16 q_num)1245 static struct vmbus_channel *get_og_chn(struct storvsc_device *stor_device,
1246 u16 q_num)
1247 {
1248 u16 slot = 0;
1249 u16 hash_qnum;
1250 const struct cpumask *node_mask;
1251 int num_channels, tgt_cpu;
1252
1253 if (stor_device->num_sc == 0)
1254 return stor_device->device->channel;
1255
1256 /*
1257 * Our channel array is sparsley populated and we
1258 * initiated I/O on a processor/hw-q that does not
1259 * currently have a designated channel. Fix this.
1260 * The strategy is simple:
1261 * I. Ensure NUMA locality
1262 * II. Distribute evenly (best effort)
1263 * III. Mapping is persistent.
1264 */
1265
1266 node_mask = cpumask_of_node(cpu_to_node(q_num));
1267
1268 num_channels = 0;
1269 for_each_cpu(tgt_cpu, &stor_device->alloced_cpus) {
1270 if (cpumask_test_cpu(tgt_cpu, node_mask))
1271 num_channels++;
1272 }
1273 if (num_channels == 0)
1274 return stor_device->device->channel;
1275
1276 hash_qnum = q_num;
1277 while (hash_qnum >= num_channels)
1278 hash_qnum -= num_channels;
1279
1280 for_each_cpu(tgt_cpu, &stor_device->alloced_cpus) {
1281 if (!cpumask_test_cpu(tgt_cpu, node_mask))
1282 continue;
1283 if (slot == hash_qnum)
1284 break;
1285 slot++;
1286 }
1287
1288 stor_device->stor_chns[q_num] = stor_device->stor_chns[tgt_cpu];
1289
1290 return stor_device->stor_chns[q_num];
1291 }
1292
1293
storvsc_do_io(struct hv_device * device,struct storvsc_cmd_request * request,u16 q_num)1294 static int storvsc_do_io(struct hv_device *device,
1295 struct storvsc_cmd_request *request, u16 q_num)
1296 {
1297 struct storvsc_device *stor_device;
1298 struct vstor_packet *vstor_packet;
1299 struct vmbus_channel *outgoing_channel, *channel;
1300 int ret = 0;
1301 const struct cpumask *node_mask;
1302 int tgt_cpu;
1303
1304 vstor_packet = &request->vstor_packet;
1305 stor_device = get_out_stor_device(device);
1306
1307 if (!stor_device)
1308 return -ENODEV;
1309
1310
1311 request->device = device;
1312 /*
1313 * Select an an appropriate channel to send the request out.
1314 */
1315 if (stor_device->stor_chns[q_num] != NULL) {
1316 outgoing_channel = stor_device->stor_chns[q_num];
1317 if (outgoing_channel->target_cpu == q_num) {
1318 /*
1319 * Ideally, we want to pick a different channel if
1320 * available on the same NUMA node.
1321 */
1322 node_mask = cpumask_of_node(cpu_to_node(q_num));
1323 for_each_cpu_wrap(tgt_cpu,
1324 &stor_device->alloced_cpus, q_num + 1) {
1325 if (!cpumask_test_cpu(tgt_cpu, node_mask))
1326 continue;
1327 if (tgt_cpu == q_num)
1328 continue;
1329 channel = stor_device->stor_chns[tgt_cpu];
1330 if (hv_get_avail_to_write_percent(
1331 &channel->outbound)
1332 > ring_avail_percent_lowater) {
1333 outgoing_channel = channel;
1334 goto found_channel;
1335 }
1336 }
1337
1338 /*
1339 * All the other channels on the same NUMA node are
1340 * busy. Try to use the channel on the current CPU
1341 */
1342 if (hv_get_avail_to_write_percent(
1343 &outgoing_channel->outbound)
1344 > ring_avail_percent_lowater)
1345 goto found_channel;
1346
1347 /*
1348 * If we reach here, all the channels on the current
1349 * NUMA node are busy. Try to find a channel in
1350 * other NUMA nodes
1351 */
1352 for_each_cpu(tgt_cpu, &stor_device->alloced_cpus) {
1353 if (cpumask_test_cpu(tgt_cpu, node_mask))
1354 continue;
1355 channel = stor_device->stor_chns[tgt_cpu];
1356 if (hv_get_avail_to_write_percent(
1357 &channel->outbound)
1358 > ring_avail_percent_lowater) {
1359 outgoing_channel = channel;
1360 goto found_channel;
1361 }
1362 }
1363 }
1364 } else {
1365 outgoing_channel = get_og_chn(stor_device, q_num);
1366 }
1367
1368 found_channel:
1369 vstor_packet->flags |= REQUEST_COMPLETION_FLAG;
1370
1371 vstor_packet->vm_srb.length = (sizeof(struct vmscsi_request) -
1372 vmscsi_size_delta);
1373
1374
1375 vstor_packet->vm_srb.sense_info_length = sense_buffer_size;
1376
1377
1378 vstor_packet->vm_srb.data_transfer_length =
1379 request->payload->range.len;
1380
1381 vstor_packet->operation = VSTOR_OPERATION_EXECUTE_SRB;
1382
1383 if (request->payload->range.len) {
1384
1385 ret = vmbus_sendpacket_mpb_desc(outgoing_channel,
1386 request->payload, request->payload_sz,
1387 vstor_packet,
1388 (sizeof(struct vstor_packet) -
1389 vmscsi_size_delta),
1390 (unsigned long)request);
1391 } else {
1392 ret = vmbus_sendpacket(outgoing_channel, vstor_packet,
1393 (sizeof(struct vstor_packet) -
1394 vmscsi_size_delta),
1395 (unsigned long)request,
1396 VM_PKT_DATA_INBAND,
1397 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
1398 }
1399
1400 if (ret != 0)
1401 return ret;
1402
1403 atomic_inc(&stor_device->num_outstanding_req);
1404
1405 return ret;
1406 }
1407
storvsc_device_alloc(struct scsi_device * sdevice)1408 static int storvsc_device_alloc(struct scsi_device *sdevice)
1409 {
1410 /*
1411 * Set blist flag to permit the reading of the VPD pages even when
1412 * the target may claim SPC-2 compliance. MSFT targets currently
1413 * claim SPC-2 compliance while they implement post SPC-2 features.
1414 * With this flag we can correctly handle WRITE_SAME_16 issues.
1415 *
1416 * Hypervisor reports SCSI_UNKNOWN type for DVD ROM device but
1417 * still supports REPORT LUN.
1418 */
1419 sdevice->sdev_bflags = BLIST_REPORTLUN2 | BLIST_TRY_VPD_PAGES;
1420
1421 return 0;
1422 }
1423
storvsc_device_configure(struct scsi_device * sdevice)1424 static int storvsc_device_configure(struct scsi_device *sdevice)
1425 {
1426 blk_queue_rq_timeout(sdevice->request_queue, (storvsc_timeout * HZ));
1427
1428 /* Ensure there are no gaps in presented sgls */
1429 blk_queue_virt_boundary(sdevice->request_queue, PAGE_SIZE - 1);
1430
1431 sdevice->no_write_same = 1;
1432
1433 /*
1434 * If the host is WIN8 or WIN8 R2, claim conformance to SPC-3
1435 * if the device is a MSFT virtual device. If the host is
1436 * WIN10 or newer, allow write_same.
1437 */
1438 if (!strncmp(sdevice->vendor, "Msft", 4)) {
1439 switch (vmstor_proto_version) {
1440 case VMSTOR_PROTO_VERSION_WIN8:
1441 case VMSTOR_PROTO_VERSION_WIN8_1:
1442 sdevice->scsi_level = SCSI_SPC_3;
1443 break;
1444 }
1445
1446 if (vmstor_proto_version >= VMSTOR_PROTO_VERSION_WIN10)
1447 sdevice->no_write_same = 0;
1448 }
1449
1450 return 0;
1451 }
1452
storvsc_get_chs(struct scsi_device * sdev,struct block_device * bdev,sector_t capacity,int * info)1453 static int storvsc_get_chs(struct scsi_device *sdev, struct block_device * bdev,
1454 sector_t capacity, int *info)
1455 {
1456 sector_t nsect = capacity;
1457 sector_t cylinders = nsect;
1458 int heads, sectors_pt;
1459
1460 /*
1461 * We are making up these values; let us keep it simple.
1462 */
1463 heads = 0xff;
1464 sectors_pt = 0x3f; /* Sectors per track */
1465 sector_div(cylinders, heads * sectors_pt);
1466 if ((sector_t)(cylinders + 1) * heads * sectors_pt < nsect)
1467 cylinders = 0xffff;
1468
1469 info[0] = heads;
1470 info[1] = sectors_pt;
1471 info[2] = (int)cylinders;
1472
1473 return 0;
1474 }
1475
storvsc_host_reset_handler(struct scsi_cmnd * scmnd)1476 static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd)
1477 {
1478 struct hv_host_device *host_dev = shost_priv(scmnd->device->host);
1479 struct hv_device *device = host_dev->dev;
1480
1481 struct storvsc_device *stor_device;
1482 struct storvsc_cmd_request *request;
1483 struct vstor_packet *vstor_packet;
1484 int ret, t;
1485
1486
1487 stor_device = get_out_stor_device(device);
1488 if (!stor_device)
1489 return FAILED;
1490
1491 request = &stor_device->reset_request;
1492 vstor_packet = &request->vstor_packet;
1493
1494 init_completion(&request->wait_event);
1495
1496 vstor_packet->operation = VSTOR_OPERATION_RESET_BUS;
1497 vstor_packet->flags = REQUEST_COMPLETION_FLAG;
1498 vstor_packet->vm_srb.path_id = stor_device->path_id;
1499
1500 ret = vmbus_sendpacket(device->channel, vstor_packet,
1501 (sizeof(struct vstor_packet) -
1502 vmscsi_size_delta),
1503 (unsigned long)&stor_device->reset_request,
1504 VM_PKT_DATA_INBAND,
1505 VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED);
1506 if (ret != 0)
1507 return FAILED;
1508
1509 t = wait_for_completion_timeout(&request->wait_event, 5*HZ);
1510 if (t == 0)
1511 return TIMEOUT_ERROR;
1512
1513
1514 /*
1515 * At this point, all outstanding requests in the adapter
1516 * should have been flushed out and return to us
1517 * There is a potential race here where the host may be in
1518 * the process of responding when we return from here.
1519 * Just wait for all in-transit packets to be accounted for
1520 * before we return from here.
1521 */
1522 storvsc_wait_to_drain(stor_device);
1523
1524 return SUCCESS;
1525 }
1526
1527 /*
1528 * The host guarantees to respond to each command, although I/O latencies might
1529 * be unbounded on Azure. Reset the timer unconditionally to give the host a
1530 * chance to perform EH.
1531 */
storvsc_eh_timed_out(struct scsi_cmnd * scmnd)1532 static enum blk_eh_timer_return storvsc_eh_timed_out(struct scsi_cmnd *scmnd)
1533 {
1534 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1535 if (scmnd->device->host->transportt == fc_transport_template)
1536 return fc_eh_timed_out(scmnd);
1537 #endif
1538 return BLK_EH_RESET_TIMER;
1539 }
1540
storvsc_scsi_cmd_ok(struct scsi_cmnd * scmnd)1541 static bool storvsc_scsi_cmd_ok(struct scsi_cmnd *scmnd)
1542 {
1543 bool allowed = true;
1544 u8 scsi_op = scmnd->cmnd[0];
1545
1546 switch (scsi_op) {
1547 /* the host does not handle WRITE_SAME, log accident usage */
1548 case WRITE_SAME:
1549 /*
1550 * smartd sends this command and the host does not handle
1551 * this. So, don't send it.
1552 */
1553 case SET_WINDOW:
1554 scmnd->result = ILLEGAL_REQUEST << 16;
1555 allowed = false;
1556 break;
1557 default:
1558 break;
1559 }
1560 return allowed;
1561 }
1562
storvsc_queuecommand(struct Scsi_Host * host,struct scsi_cmnd * scmnd)1563 static int storvsc_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *scmnd)
1564 {
1565 int ret;
1566 struct hv_host_device *host_dev = shost_priv(host);
1567 struct hv_device *dev = host_dev->dev;
1568 struct storvsc_cmd_request *cmd_request = scsi_cmd_priv(scmnd);
1569 int i;
1570 struct scatterlist *sgl;
1571 unsigned int sg_count = 0;
1572 struct vmscsi_request *vm_srb;
1573 struct scatterlist *cur_sgl;
1574 struct vmbus_packet_mpb_array *payload;
1575 u32 payload_sz;
1576 u32 length;
1577
1578 if (vmstor_proto_version <= VMSTOR_PROTO_VERSION_WIN8) {
1579 /*
1580 * On legacy hosts filter unimplemented commands.
1581 * Future hosts are expected to correctly handle
1582 * unsupported commands. Furthermore, it is
1583 * possible that some of the currently
1584 * unsupported commands maybe supported in
1585 * future versions of the host.
1586 */
1587 if (!storvsc_scsi_cmd_ok(scmnd)) {
1588 scmnd->scsi_done(scmnd);
1589 return 0;
1590 }
1591 }
1592
1593 /* Setup the cmd request */
1594 cmd_request->cmd = scmnd;
1595
1596 vm_srb = &cmd_request->vstor_packet.vm_srb;
1597 vm_srb->win8_extension.time_out_value = 60;
1598
1599 vm_srb->win8_extension.srb_flags |=
1600 SRB_FLAGS_DISABLE_SYNCH_TRANSFER;
1601
1602 if (scmnd->device->tagged_supported) {
1603 vm_srb->win8_extension.srb_flags |=
1604 (SRB_FLAGS_QUEUE_ACTION_ENABLE | SRB_FLAGS_NO_QUEUE_FREEZE);
1605 vm_srb->win8_extension.queue_tag = SP_UNTAGGED;
1606 vm_srb->win8_extension.queue_action = SRB_SIMPLE_TAG_REQUEST;
1607 }
1608
1609 /* Build the SRB */
1610 switch (scmnd->sc_data_direction) {
1611 case DMA_TO_DEVICE:
1612 vm_srb->data_in = WRITE_TYPE;
1613 vm_srb->win8_extension.srb_flags |= SRB_FLAGS_DATA_OUT;
1614 break;
1615 case DMA_FROM_DEVICE:
1616 vm_srb->data_in = READ_TYPE;
1617 vm_srb->win8_extension.srb_flags |= SRB_FLAGS_DATA_IN;
1618 break;
1619 case DMA_NONE:
1620 vm_srb->data_in = UNKNOWN_TYPE;
1621 vm_srb->win8_extension.srb_flags |= SRB_FLAGS_NO_DATA_TRANSFER;
1622 break;
1623 default:
1624 /*
1625 * This is DMA_BIDIRECTIONAL or something else we are never
1626 * supposed to see here.
1627 */
1628 WARN(1, "Unexpected data direction: %d\n",
1629 scmnd->sc_data_direction);
1630 return -EINVAL;
1631 }
1632
1633
1634 vm_srb->port_number = host_dev->port;
1635 vm_srb->path_id = scmnd->device->channel;
1636 vm_srb->target_id = scmnd->device->id;
1637 vm_srb->lun = scmnd->device->lun;
1638
1639 vm_srb->cdb_length = scmnd->cmd_len;
1640
1641 memcpy(vm_srb->cdb, scmnd->cmnd, vm_srb->cdb_length);
1642
1643 sgl = (struct scatterlist *)scsi_sglist(scmnd);
1644 sg_count = scsi_sg_count(scmnd);
1645
1646 length = scsi_bufflen(scmnd);
1647 payload = (struct vmbus_packet_mpb_array *)&cmd_request->mpb;
1648 payload_sz = sizeof(cmd_request->mpb);
1649
1650 if (sg_count) {
1651 if (sg_count > MAX_PAGE_BUFFER_COUNT) {
1652
1653 payload_sz = (sg_count * sizeof(u64) +
1654 sizeof(struct vmbus_packet_mpb_array));
1655 payload = kzalloc(payload_sz, GFP_ATOMIC);
1656 if (!payload)
1657 return SCSI_MLQUEUE_DEVICE_BUSY;
1658 }
1659
1660 payload->range.len = length;
1661 payload->range.offset = sgl[0].offset;
1662
1663 cur_sgl = sgl;
1664 for (i = 0; i < sg_count; i++) {
1665 payload->range.pfn_array[i] =
1666 page_to_pfn(sg_page((cur_sgl)));
1667 cur_sgl = sg_next(cur_sgl);
1668 }
1669 }
1670
1671 cmd_request->payload = payload;
1672 cmd_request->payload_sz = payload_sz;
1673
1674 /* Invokes the vsc to start an IO */
1675 ret = storvsc_do_io(dev, cmd_request, get_cpu());
1676 put_cpu();
1677
1678 if (ret == -EAGAIN) {
1679 if (payload_sz > sizeof(cmd_request->mpb))
1680 kfree(payload);
1681 /* no more space */
1682 return SCSI_MLQUEUE_DEVICE_BUSY;
1683 }
1684
1685 return 0;
1686 }
1687
1688 static struct scsi_host_template scsi_driver = {
1689 .module = THIS_MODULE,
1690 .name = "storvsc_host_t",
1691 .cmd_size = sizeof(struct storvsc_cmd_request),
1692 .bios_param = storvsc_get_chs,
1693 .queuecommand = storvsc_queuecommand,
1694 .eh_host_reset_handler = storvsc_host_reset_handler,
1695 .proc_name = "storvsc_host",
1696 .eh_timed_out = storvsc_eh_timed_out,
1697 .slave_alloc = storvsc_device_alloc,
1698 .slave_configure = storvsc_device_configure,
1699 .cmd_per_lun = 2048,
1700 .this_id = -1,
1701 .use_clustering = ENABLE_CLUSTERING,
1702 /* Make sure we dont get a sg segment crosses a page boundary */
1703 .dma_boundary = PAGE_SIZE-1,
1704 .no_write_same = 1,
1705 .track_queue_depth = 1,
1706 };
1707
1708 enum {
1709 SCSI_GUID,
1710 IDE_GUID,
1711 SFC_GUID,
1712 };
1713
1714 static const struct hv_vmbus_device_id id_table[] = {
1715 /* SCSI guid */
1716 { HV_SCSI_GUID,
1717 .driver_data = SCSI_GUID
1718 },
1719 /* IDE guid */
1720 { HV_IDE_GUID,
1721 .driver_data = IDE_GUID
1722 },
1723 /* Fibre Channel GUID */
1724 {
1725 HV_SYNTHFC_GUID,
1726 .driver_data = SFC_GUID
1727 },
1728 { },
1729 };
1730
1731 MODULE_DEVICE_TABLE(vmbus, id_table);
1732
storvsc_probe(struct hv_device * device,const struct hv_vmbus_device_id * dev_id)1733 static int storvsc_probe(struct hv_device *device,
1734 const struct hv_vmbus_device_id *dev_id)
1735 {
1736 int ret;
1737 int num_cpus = num_online_cpus();
1738 struct Scsi_Host *host;
1739 struct hv_host_device *host_dev;
1740 bool dev_is_ide = ((dev_id->driver_data == IDE_GUID) ? true : false);
1741 bool is_fc = ((dev_id->driver_data == SFC_GUID) ? true : false);
1742 int target = 0;
1743 struct storvsc_device *stor_device;
1744 int max_luns_per_target;
1745 int max_targets;
1746 int max_channels;
1747 int max_sub_channels = 0;
1748
1749 /*
1750 * Based on the windows host we are running on,
1751 * set state to properly communicate with the host.
1752 */
1753
1754 if (vmbus_proto_version < VERSION_WIN8) {
1755 max_luns_per_target = STORVSC_IDE_MAX_LUNS_PER_TARGET;
1756 max_targets = STORVSC_IDE_MAX_TARGETS;
1757 max_channels = STORVSC_IDE_MAX_CHANNELS;
1758 } else {
1759 max_luns_per_target = STORVSC_MAX_LUNS_PER_TARGET;
1760 max_targets = STORVSC_MAX_TARGETS;
1761 max_channels = STORVSC_MAX_CHANNELS;
1762 /*
1763 * On Windows8 and above, we support sub-channels for storage
1764 * on SCSI and FC controllers.
1765 * The number of sub-channels offerred is based on the number of
1766 * VCPUs in the guest.
1767 */
1768 if (!dev_is_ide)
1769 max_sub_channels =
1770 (num_cpus - 1) / storvsc_vcpus_per_sub_channel;
1771 }
1772
1773 scsi_driver.can_queue = max_outstanding_req_per_channel *
1774 (max_sub_channels + 1) *
1775 (100 - ring_avail_percent_lowater) / 100;
1776
1777 host = scsi_host_alloc(&scsi_driver,
1778 sizeof(struct hv_host_device));
1779 if (!host)
1780 return -ENOMEM;
1781
1782 host_dev = shost_priv(host);
1783 memset(host_dev, 0, sizeof(struct hv_host_device));
1784
1785 host_dev->port = host->host_no;
1786 host_dev->dev = device;
1787 host_dev->host = host;
1788
1789
1790 stor_device = kzalloc(sizeof(struct storvsc_device), GFP_KERNEL);
1791 if (!stor_device) {
1792 ret = -ENOMEM;
1793 goto err_out0;
1794 }
1795
1796 stor_device->destroy = false;
1797 stor_device->open_sub_channel = false;
1798 init_waitqueue_head(&stor_device->waiting_to_drain);
1799 stor_device->device = device;
1800 stor_device->host = host;
1801 hv_set_drvdata(device, stor_device);
1802
1803 stor_device->port_number = host->host_no;
1804 ret = storvsc_connect_to_vsp(device, storvsc_ringbuffer_size, is_fc);
1805 if (ret)
1806 goto err_out1;
1807
1808 host_dev->path = stor_device->path_id;
1809 host_dev->target = stor_device->target_id;
1810
1811 switch (dev_id->driver_data) {
1812 case SFC_GUID:
1813 host->max_lun = STORVSC_FC_MAX_LUNS_PER_TARGET;
1814 host->max_id = STORVSC_FC_MAX_TARGETS;
1815 host->max_channel = STORVSC_FC_MAX_CHANNELS - 1;
1816 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1817 host->transportt = fc_transport_template;
1818 #endif
1819 break;
1820
1821 case SCSI_GUID:
1822 host->max_lun = max_luns_per_target;
1823 host->max_id = max_targets;
1824 host->max_channel = max_channels - 1;
1825 break;
1826
1827 default:
1828 host->max_lun = STORVSC_IDE_MAX_LUNS_PER_TARGET;
1829 host->max_id = STORVSC_IDE_MAX_TARGETS;
1830 host->max_channel = STORVSC_IDE_MAX_CHANNELS - 1;
1831 break;
1832 }
1833 /* max cmd length */
1834 host->max_cmd_len = STORVSC_MAX_CMD_LEN;
1835
1836 /*
1837 * set the table size based on the info we got
1838 * from the host.
1839 */
1840 host->sg_tablesize = (stor_device->max_transfer_bytes >> PAGE_SHIFT);
1841 /*
1842 * Set the number of HW queues we are supporting.
1843 */
1844 if (stor_device->num_sc != 0)
1845 host->nr_hw_queues = stor_device->num_sc + 1;
1846
1847 /*
1848 * Set the error handler work queue.
1849 */
1850 host_dev->handle_error_wq =
1851 alloc_ordered_workqueue("storvsc_error_wq_%d",
1852 WQ_MEM_RECLAIM,
1853 host->host_no);
1854 if (!host_dev->handle_error_wq)
1855 goto err_out2;
1856 INIT_WORK(&host_dev->host_scan_work, storvsc_host_scan);
1857 /* Register the HBA and start the scsi bus scan */
1858 ret = scsi_add_host(host, &device->device);
1859 if (ret != 0)
1860 goto err_out3;
1861
1862 if (!dev_is_ide) {
1863 scsi_scan_host(host);
1864 } else {
1865 target = (device->dev_instance.b[5] << 8 |
1866 device->dev_instance.b[4]);
1867 ret = scsi_add_device(host, 0, target, 0);
1868 if (ret)
1869 goto err_out4;
1870 }
1871 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1872 if (host->transportt == fc_transport_template) {
1873 struct fc_rport_identifiers ids = {
1874 .roles = FC_PORT_ROLE_FCP_DUMMY_INITIATOR,
1875 };
1876
1877 fc_host_node_name(host) = stor_device->node_name;
1878 fc_host_port_name(host) = stor_device->port_name;
1879 stor_device->rport = fc_remote_port_add(host, 0, &ids);
1880 if (!stor_device->rport) {
1881 ret = -ENOMEM;
1882 goto err_out4;
1883 }
1884 }
1885 #endif
1886 return 0;
1887
1888 err_out4:
1889 scsi_remove_host(host);
1890
1891 err_out3:
1892 destroy_workqueue(host_dev->handle_error_wq);
1893
1894 err_out2:
1895 /*
1896 * Once we have connected with the host, we would need to
1897 * to invoke storvsc_dev_remove() to rollback this state and
1898 * this call also frees up the stor_device; hence the jump around
1899 * err_out1 label.
1900 */
1901 storvsc_dev_remove(device);
1902 goto err_out0;
1903
1904 err_out1:
1905 kfree(stor_device->stor_chns);
1906 kfree(stor_device);
1907
1908 err_out0:
1909 scsi_host_put(host);
1910 return ret;
1911 }
1912
storvsc_remove(struct hv_device * dev)1913 static int storvsc_remove(struct hv_device *dev)
1914 {
1915 struct storvsc_device *stor_device = hv_get_drvdata(dev);
1916 struct Scsi_Host *host = stor_device->host;
1917 struct hv_host_device *host_dev = shost_priv(host);
1918
1919 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1920 if (host->transportt == fc_transport_template) {
1921 fc_remote_port_delete(stor_device->rport);
1922 fc_remove_host(host);
1923 }
1924 #endif
1925 destroy_workqueue(host_dev->handle_error_wq);
1926 scsi_remove_host(host);
1927 storvsc_dev_remove(dev);
1928 scsi_host_put(host);
1929
1930 return 0;
1931 }
1932
1933 static struct hv_driver storvsc_drv = {
1934 .name = KBUILD_MODNAME,
1935 .id_table = id_table,
1936 .probe = storvsc_probe,
1937 .remove = storvsc_remove,
1938 .driver = {
1939 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
1940 },
1941 };
1942
1943 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1944 static struct fc_function_template fc_transport_functions = {
1945 .show_host_node_name = 1,
1946 .show_host_port_name = 1,
1947 };
1948 #endif
1949
storvsc_drv_init(void)1950 static int __init storvsc_drv_init(void)
1951 {
1952 int ret;
1953
1954 /*
1955 * Divide the ring buffer data size (which is 1 page less
1956 * than the ring buffer size since that page is reserved for
1957 * the ring buffer indices) by the max request size (which is
1958 * vmbus_channel_packet_multipage_buffer + struct vstor_packet + u64)
1959 */
1960 max_outstanding_req_per_channel =
1961 ((storvsc_ringbuffer_size - PAGE_SIZE) /
1962 ALIGN(MAX_MULTIPAGE_BUFFER_PACKET +
1963 sizeof(struct vstor_packet) + sizeof(u64) -
1964 vmscsi_size_delta,
1965 sizeof(u64)));
1966
1967 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1968 fc_transport_template = fc_attach_transport(&fc_transport_functions);
1969 if (!fc_transport_template)
1970 return -ENODEV;
1971 #endif
1972
1973 ret = vmbus_driver_register(&storvsc_drv);
1974
1975 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1976 if (ret)
1977 fc_release_transport(fc_transport_template);
1978 #endif
1979
1980 return ret;
1981 }
1982
storvsc_drv_exit(void)1983 static void __exit storvsc_drv_exit(void)
1984 {
1985 vmbus_driver_unregister(&storvsc_drv);
1986 #if IS_ENABLED(CONFIG_SCSI_FC_ATTRS)
1987 fc_release_transport(fc_transport_template);
1988 #endif
1989 }
1990
1991 MODULE_LICENSE("GPL");
1992 MODULE_DESCRIPTION("Microsoft Hyper-V virtual storage driver");
1993 module_init(storvsc_drv_init);
1994 module_exit(storvsc_drv_exit);
1995
